cmds-check.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <fcntl.h>
  23 #include <sys/types.h>
  24 #include <sys/stat.h>
  25 #include <unistd.h>
  26 #include <getopt.h>
  27 #include <uuid/uuid.h>
  28 #include "ctree.h"
  29 #include "volumes.h"
  30 #include "repair.h"
  31 #include "disk-io.h"
  32 #include "print-tree.h"
  33 #include "task-utils.h"
  34 #include "transaction.h"
  35 #include "utils.h"
  36 #include "commands.h"
  37 #include "free-space-cache.h"
  38 #include "free-space-tree.h"
  39 #include "btrfsck.h"
  40 #include "qgroup-verify.h"
  41 #include "rbtree-utils.h"
  42 #include "backref.h"
  43 #include "ulist.h"
  44
  45 enum task_position {
  46         TASK_EXTENTS,
  47         TASK_FREE_SPACE,
  48         TASK_FS_ROOTS,
  49         TASK_NOTHING, /* have to be the last element */
  50 };
  51
  52 struct task_ctx {
  53         int progress_enabled;
  54         enum task_position tp;
  55
  56         struct task_info *info;
  57 };
  58
  59 static u64 bytes_used = 0;
  60 static u64 total_csum_bytes = 0;
  61 static u64 total_btree_bytes = 0;
  62 static u64 total_fs_tree_bytes = 0;
  63 static u64 total_extent_tree_bytes = 0;
  64 static u64 btree_space_waste = 0;
  65 static u64 data_bytes_allocated = 0;
  66 static u64 data_bytes_referenced = 0;
  67 static int found_old_backref = 0;
  68 static LIST_HEAD(duplicate_extents);
  69 static LIST_HEAD(delete_items);
  70 static int no_holes = 0;
  71 static int init_extent_tree = 0;
  72 static int check_data_csum = 0;
  73 static struct btrfs_fs_info *global_info;
  74 static struct task_ctx ctx = { 0 };
  75 static struct cache_tree *roots_info_cache = NULL;
  76
  77 enum btrfs_check_mode {
  78         CHECK_MODE_ORIGINAL,
  79         CHECK_MODE_LOWMEM,
  80         CHECK_MODE_UNKNOWN,
  81         CHECK_MODE_DEFAULT = CHECK_MODE_ORIGINAL
  82 };
  83
  84 static enum btrfs_check_mode check_mode = CHECK_MODE_DEFAULT;
  85
  86 struct extent_backref {
  87         struct list_head list;
  88         unsigned int is_data:1;
  89         unsigned int found_extent_tree:1;
  90         unsigned int full_backref:1;
  91         unsigned int found_ref:1;
  92         unsigned int broken:1;
  93 };
  94
  95 static inline struct extent_backref* to_extent_backref(struct list_head *entry)
  96 {
  97         return list_entry(entry, struct extent_backref, list);
  98 }
  99
 100 struct data_backref {
 101         struct extent_backref node;
 102         union {
 103                 u64 parent;
 104                 u64 root;
 105         };
 106         u64 owner;
 107         u64 offset;
 108         u64 disk_bytenr;
 109         u64 bytes;
 110         u64 ram_bytes;
 111         u32 num_refs;
 112         u32 found_ref;
 113 };
 114
 115 static inline struct data_backref* to_data_backref(struct extent_backref *back)
 116 {
 117         return container_of(back, struct data_backref, node);
 118 }
 119
 120 /*
 121  * Much like data_backref, just removed the undetermined members
 122  * and change it to use list_head.
 123  * During extent scan, it is stored in root->orphan_data_extent.
 124  * During fs tree scan, it is then moved to inode_rec->orphan_data_extents.
 125  */
 126 struct orphan_data_extent {
 127         struct list_head list;
 128         u64 root;
 129         u64 objectid;
 130         u64 offset;
 131         u64 disk_bytenr;
 132         u64 disk_len;
 133 };
 134
 135 struct tree_backref {
 136         struct extent_backref node;
 137         union {
 138                 u64 parent;
 139                 u64 root;
 140         };
 141 };
 142
 143 static inline struct tree_backref* to_tree_backref(struct extent_backref *back)
 144 {
 145         return container_of(back, struct tree_backref, node);
 146 }
 147
 148 /* Explicit initialization for extent_record::flag_block_full_backref */
 149 enum { FLAG_UNSET = 2 };
 150
 151 struct extent_record {
 152         struct list_head backrefs;
 153         struct list_head dups;
 154         struct list_head list;
 155         struct cache_extent cache;
 156         struct btrfs_disk_key parent_key;
 157         u64 start;
 158         u64 max_size;
 159         u64 nr;
 160         u64 refs;
 161         u64 extent_item_refs;
 162         u64 generation;
 163         u64 parent_generation;
 164         u64 info_objectid;
 165         u32 num_duplicates;
 166         u8 info_level;
 167         unsigned int flag_block_full_backref:2;
 168         unsigned int found_rec:1;
 169         unsigned int content_checked:1;
 170         unsigned int owner_ref_checked:1;
 171         unsigned int is_root:1;
 172         unsigned int metadata:1;
 173         unsigned int bad_full_backref:1;
 174         unsigned int crossing_stripes:1;
 175         unsigned int wrong_chunk_type:1;
 176 };
 177
 178 static inline struct extent_record* to_extent_record(struct list_head *entry)
 179 {
 180         return container_of(entry, struct extent_record, list);
 181 }
 182
 183 struct inode_backref {
 184         struct list_head list;
 185         unsigned int found_dir_item:1;
 186         unsigned int found_dir_index:1;
 187         unsigned int found_inode_ref:1;
 188         u8 filetype;
 189         u8 ref_type;
 190         int errors;
 191         u64 dir;
 192         u64 index;
 193         u16 namelen;
 194         char name[0];
 195 };
 196
 197 static inline struct inode_backref* to_inode_backref(struct list_head *entry)
 198 {
 199         return list_entry(entry, struct inode_backref, list);
 200 }
 201
 202 struct root_item_record {
 203         struct list_head list;
 204         u64 objectid;
 205         u64 bytenr;
 206         u64 last_snapshot;
 207         u8 level;
 208         u8 drop_level;
 209         int level_size;
 210         struct btrfs_key drop_key;
 211 };
 212
 213 #define REF_ERR_NO_DIR_ITEM             (1 << 0)
 214 #define REF_ERR_NO_DIR_INDEX            (1 << 1)
 215 #define REF_ERR_NO_INODE_REF            (1 << 2)
 216 #define REF_ERR_DUP_DIR_ITEM            (1 << 3)
 217 #define REF_ERR_DUP_DIR_INDEX           (1 << 4)
 218 #define REF_ERR_DUP_INODE_REF           (1 << 5)
 219 #define REF_ERR_INDEX_UNMATCH           (1 << 6)
 220 #define REF_ERR_FILETYPE_UNMATCH        (1 << 7)
 221 #define REF_ERR_NAME_TOO_LONG           (1 << 8) // 100
 222 #define REF_ERR_NO_ROOT_REF             (1 << 9)
 223 #define REF_ERR_NO_ROOT_BACKREF         (1 << 10)
 224 #define REF_ERR_DUP_ROOT_REF            (1 << 11)
 225 #define REF_ERR_DUP_ROOT_BACKREF        (1 << 12)
 226
 227 struct file_extent_hole {
 228         struct rb_node node;
 229         u64 start;
 230         u64 len;
 231 };
 232
 233 struct inode_record {
 234         struct list_head backrefs;
 235         unsigned int checked:1;
 236         unsigned int merging:1;
 237         unsigned int found_inode_item:1;
 238         unsigned int found_dir_item:1;
 239         unsigned int found_file_extent:1;
 240         unsigned int found_csum_item:1;
 241         unsigned int some_csum_missing:1;
 242         unsigned int nodatasum:1;
 243         int errors;
 244
 245         u64 ino;
 246         u32 nlink;
 247         u32 imode;
 248         u64 isize;
 249         u64 nbytes;
 250
 251         u32 found_link;
 252         u64 found_size;
 253         u64 extent_start;
 254         u64 extent_end;
 255         struct rb_root holes;
 256         struct list_head orphan_extents;
 257
 258         u32 refs;
 259 };
 260
 261 #define I_ERR_NO_INODE_ITEM             (1 << 0)
 262 #define I_ERR_NO_ORPHAN_ITEM            (1 << 1)
 263 #define I_ERR_DUP_INODE_ITEM            (1 << 2)
 264 #define I_ERR_DUP_DIR_INDEX             (1 << 3)
 265 #define I_ERR_ODD_DIR_ITEM              (1 << 4)
 266 #define I_ERR_ODD_FILE_EXTENT           (1 << 5)
 267 #define I_ERR_BAD_FILE_EXTENT           (1 << 6)
 268 #define I_ERR_FILE_EXTENT_OVERLAP       (1 << 7)
 269 #define I_ERR_FILE_EXTENT_DISCOUNT      (1 << 8) // 100
 270 #define I_ERR_DIR_ISIZE_WRONG           (1 << 9)
 271 #define I_ERR_FILE_NBYTES_WRONG         (1 << 10) // 400
 272 #define I_ERR_ODD_CSUM_ITEM             (1 << 11)
 273 #define I_ERR_SOME_CSUM_MISSING         (1 << 12)
 274 #define I_ERR_LINK_COUNT_WRONG          (1 << 13)
 275 #define I_ERR_FILE_EXTENT_ORPHAN        (1 << 14)
 276
 277 struct root_backref {
 278         struct list_head list;
 279         unsigned int found_dir_item:1;
 280         unsigned int found_dir_index:1;
 281         unsigned int found_back_ref:1;
 282         unsigned int found_forward_ref:1;
 283         unsigned int reachable:1;
 284         int errors;
 285         u64 ref_root;
 286         u64 dir;
 287         u64 index;
 288         u16 namelen;
 289         char name[0];
 290 };
 291
 292 static inline struct root_backref* to_root_backref(struct list_head *entry)
 293 {
 294         return list_entry(entry, struct root_backref, list);
 295 }
 296
 297 struct root_record {
 298         struct list_head backrefs;
 299         struct cache_extent cache;
 300         unsigned int found_root_item:1;
 301         u64 objectid;
 302         u32 found_ref;
 303 };
 304
 305 struct ptr_node {
 306         struct cache_extent cache;
 307         void *data;
 308 };
 309
 310 struct shared_node {
 311         struct cache_extent cache;
 312         struct cache_tree root_cache;
 313         struct cache_tree inode_cache;
 314         struct inode_record *current;
 315         u32 refs;
 316 };
 317
 318 struct block_info {
 319         u64 start;
 320         u32 size;
 321 };
 322
 323 struct walk_control {
 324         struct cache_tree shared;
 325         struct shared_node *nodes[BTRFS_MAX_LEVEL];
 326         int active_node;
 327         int root_level;
 328 };
 329
 330 struct bad_item {
 331         struct btrfs_key key;
 332         u64 root_id;
 333         struct list_head list;
 334 };
 335
 336 struct extent_entry {
 337         u64 bytenr;
 338         u64 bytes;
 339         int count;
 340         int broken;
 341         struct list_head list;
 342 };
 343
 344 struct root_item_info {
 345         /* level of the root */
 346         u8 level;
 347         /* number of nodes at this level, must be 1 for a root */
 348         int node_count;
 349         u64 bytenr;
 350         u64 gen;
 351         struct cache_extent cache_extent;
 352 };
 353
 354 /*
 355  * Error bit for low memory mode check.
 356  *
 357  * Currently no caller cares about it yet.  Just internal use for error
 358  * classification.
 359  */
 360 #define BACKREF_MISSING         (1 << 0) /* Backref missing in extent tree */
 361 #define BACKREF_MISMATCH        (1 << 1) /* Backref exists but does not match */
 362 #define BYTES_UNALIGNED         (1 << 2) /* Some bytes are not aligned */
 363 #define REFERENCER_MISSING      (1 << 3) /* Referencer not found */
 364 #define REFERENCER_MISMATCH     (1 << 4) /* Referenceer found but does not match */
 365 #define CROSSING_STRIPE_BOUNDARY (1 << 4) /* For kernel scrub workaround */
 366 #define ITEM_SIZE_MISMATCH      (1 << 5) /* Bad item size */
 367 #define UNKNOWN_TYPE            (1 << 6) /* Unknown type */
 368 #define ACCOUNTING_MISMATCH     (1 << 7) /* Used space accounting error */
 369 #define CHUNK_TYPE_MISMATCH     (1 << 8)
 370
 371 static void *print_status_check(void *p)
 372 {
 373         struct task_ctx *priv = p;
 374         const char work_indicator[] = { '.', 'o', 'O', 'o' };
 375         uint32_t count = 0;
 376         static char *task_position_string[] = {
 377                 "checking extents",
 378                 "checking free space cache",
 379                 "checking fs roots",
 380         };
 381
 382         task_period_start(priv->info, 1000 /* 1s */);
 383
 384         if (priv->tp == TASK_NOTHING)
 385                 return NULL;
 386
 387         while (1) {
 388                 printf("%s [%c]\r", task_position_string[priv->tp],
 389                                 work_indicator[count % 4]);
 390                 count++;
 391                 fflush(stdout);
 392                 task_period_wait(priv->info);
 393         }
 394         return NULL;
 395 }
 396
 397 static int print_status_return(void *p)
 398 {
 399         printf("\n");
 400         fflush(stdout);
 401
 402         return 0;
 403 }
 404
 405 static enum btrfs_check_mode parse_check_mode(const char *str)
 406 {
 407         if (strcmp(str, "lowmem") == 0)
 408                 return CHECK_MODE_LOWMEM;
 409         if (strcmp(str, "orig") == 0)
 410                 return CHECK_MODE_ORIGINAL;
 411         if (strcmp(str, "original") == 0)
 412                 return CHECK_MODE_ORIGINAL;
 413
 414         return CHECK_MODE_UNKNOWN;
 415 }
 416
 417 /* Compatible function to allow reuse of old codes */
 418 static u64 first_extent_gap(struct rb_root *holes)
 419 {
 420         struct file_extent_hole *hole;
 421
 422         if (RB_EMPTY_ROOT(holes))
 423                 return (u64)-1;
 424
 425         hole = rb_entry(rb_first(holes), struct file_extent_hole, node);
 426         return hole->start;
 427 }
 428
 429 static int compare_hole(struct rb_node *node1, struct rb_node *node2)
 430 {
 431         struct file_extent_hole *hole1;
 432         struct file_extent_hole *hole2;
 433
 434         hole1 = rb_entry(node1, struct file_extent_hole, node);
 435         hole2 = rb_entry(node2, struct file_extent_hole, node);
 436
 437         if (hole1->start > hole2->start)
 438                 return -1;
 439         if (hole1->start < hole2->start)
 440                 return 1;
 441         /* Now hole1->start == hole2->start */
 442         if (hole1->len >= hole2->len)
 443                 /*
 444                  * Hole 1 will be merge center
 445                  * Same hole will be merged later
 446                  */
 447                 return -1;
 448         /* Hole 2 will be merge center */
 449         return 1;
 450 }
 451
 452 /*
 453  * Add a hole to the record
 454  *
 455  * This will do hole merge for copy_file_extent_holes(),
 456  * which will ensure there won't be continuous holes.
 457  */
 458 static int add_file_extent_hole(struct rb_root *holes,
 459                                 u64 start, u64 len)
 460 {
 461         struct file_extent_hole *hole;
 462         struct file_extent_hole *prev = NULL;
 463         struct file_extent_hole *next = NULL;
 464
 465         hole = malloc(sizeof(*hole));
 466         if (!hole)
 467                 return -ENOMEM;
 468         hole->start = start;
 469         hole->len = len;
 470         /* Since compare will not return 0, no -EEXIST will happen */
 471         rb_insert(holes, &hole->node, compare_hole);
 472
 473         /* simple merge with previous hole */
 474         if (rb_prev(&hole->node))
 475                 prev = rb_entry(rb_prev(&hole->node), struct file_extent_hole,
 476                                 node);
 477         if (prev && prev->start + prev->len >= hole->start) {
 478                 hole->len = hole->start + hole->len - prev->start;
 479                 hole->start = prev->start;
 480                 rb_erase(&prev->node, holes);
 481                 free(prev);
 482                 prev = NULL;
 483         }
 484
 485         /* iterate merge with next holes */
 486         while (1) {
 487                 if (!rb_next(&hole->node))
 488                         break;
 489                 next = rb_entry(rb_next(&hole->node), struct file_extent_hole,
 490                                         node);
 491                 if (hole->start + hole->len >= next->start) {
 492                         if (hole->start + hole->len <= next->start + next->len)
 493                                 hole->len = next->start + next->len -
 494                                             hole->start;
 495                         rb_erase(&next->node, holes);
 496                         free(next);
 497                         next = NULL;
 498                 } else
 499                         break;
 500         }
 501         return 0;
 502 }
 503
 504 static int compare_hole_range(struct rb_node *node, void *data)
 505 {
 506         struct file_extent_hole *hole;
 507         u64 start;
 508
 509         hole = (struct file_extent_hole *)data;
 510         start = hole->start;
 511
 512         hole = rb_entry(node, struct file_extent_hole, node);
 513         if (start < hole->start)
 514                 return -1;
 515         if (start >= hole->start && start < hole->start + hole->len)
 516                 return 0;
 517         return 1;
 518 }
 519
 520 /*
 521  * Delete a hole in the record
 522  *
 523  * This will do the hole split and is much restrict than add.
 524  */
 525 static int del_file_extent_hole(struct rb_root *holes,
 526                                 u64 start, u64 len)
 527 {
 528         struct file_extent_hole *hole;
 529         struct file_extent_hole tmp;
 530         u64 prev_start = 0;
 531         u64 prev_len = 0;
 532         u64 next_start = 0;
 533         u64 next_len = 0;
 534         struct rb_node *node;
 535         int have_prev = 0;
 536         int have_next = 0;
 537         int ret = 0;
 538
 539         tmp.start = start;
 540         tmp.len = len;
 541         node = rb_search(holes, &tmp, compare_hole_range, NULL);
 542         if (!node)
 543                 return -EEXIST;
 544         hole = rb_entry(node, struct file_extent_hole, node);
 545         if (start + len > hole->start + hole->len)
 546                 return -EEXIST;
 547
 548         /*
 549          * Now there will be no overlap, delete the hole and re-add the
 550          * split(s) if they exists.
 551          */
 552         if (start > hole->start) {
 553                 prev_start = hole->start;
 554                 prev_len = start - hole->start;
 555                 have_prev = 1;
 556         }
 557         if (hole->start + hole->len > start + len) {
 558                 next_start = start + len;
 559                 next_len = hole->start + hole->len - start - len;
 560                 have_next = 1;
 561         }
 562         rb_erase(node, holes);
 563         free(hole);
 564         if (have_prev) {
 565                 ret = add_file_extent_hole(holes, prev_start, prev_len);
 566                 if (ret < 0)
 567                         return ret;
 568         }
 569         if (have_next) {
 570                 ret = add_file_extent_hole(holes, next_start, next_len);
 571                 if (ret < 0)
 572                         return ret;
 573         }
 574         return 0;
 575 }
 576
 577 static int copy_file_extent_holes(struct rb_root *dst,
 578                                   struct rb_root *src)
 579 {
 580         struct file_extent_hole *hole;
 581         struct rb_node *node;
 582         int ret = 0;
 583
 584         node = rb_first(src);
 585         while (node) {
 586                 hole = rb_entry(node, struct file_extent_hole, node);
 587                 ret = add_file_extent_hole(dst, hole->start, hole->len);
 588                 if (ret)
 589                         break;
 590                 node = rb_next(node);
 591         }
 592         return ret;
 593 }
 594
 595 static void free_file_extent_holes(struct rb_root *holes)
 596 {
 597         struct rb_node *node;
 598         struct file_extent_hole *hole;
 599
 600         node = rb_first(holes);
 601         while (node) {
 602                 hole = rb_entry(node, struct file_extent_hole, node);
 603                 rb_erase(node, holes);
 604                 free(hole);
 605                 node = rb_first(holes);
 606         }
 607 }
 608
 609 static void reset_cached_block_groups(struct btrfs_fs_info *fs_info);
 610
 611 static void record_root_in_trans(struct btrfs_trans_handle *trans,
 612                                  struct btrfs_root *root)
 613 {
 614         if (root->last_trans != trans->transid) {
 615                 root->track_dirty = 1;
 616                 root->last_trans = trans->transid;
 617                 root->commit_root = root->node;
 618                 extent_buffer_get(root->node);
 619         }
 620 }
 621
 622 static u8 imode_to_type(u32 imode)
 623 {
 624 #define S_SHIFT 12
 625         static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
 626                 [S_IFREG >> S_SHIFT]    = BTRFS_FT_REG_FILE,
 627                 [S_IFDIR >> S_SHIFT]    = BTRFS_FT_DIR,
 628                 [S_IFCHR >> S_SHIFT]    = BTRFS_FT_CHRDEV,
 629                 [S_IFBLK >> S_SHIFT]    = BTRFS_FT_BLKDEV,
 630                 [S_IFIFO >> S_SHIFT]    = BTRFS_FT_FIFO,
 631                 [S_IFSOCK >> S_SHIFT]   = BTRFS_FT_SOCK,
 632                 [S_IFLNK >> S_SHIFT]    = BTRFS_FT_SYMLINK,
 633         };
 634
 635         return btrfs_type_by_mode[(imode & S_IFMT) >> S_SHIFT];
 636 #undef S_SHIFT
 637 }
 638
 639 static int device_record_compare(struct rb_node *node1, struct rb_node *node2)
 640 {
 641         struct device_record *rec1;
 642         struct device_record *rec2;
 643
 644         rec1 = rb_entry(node1, struct device_record, node);
 645         rec2 = rb_entry(node2, struct device_record, node);
 646         if (rec1->devid > rec2->devid)
 647                 return -1;
 648         else if (rec1->devid < rec2->devid)
 649                 return 1;
 650         else
 651                 return 0;
 652 }
 653
 654 static struct inode_record *clone_inode_rec(struct inode_record *orig_rec)
 655 {
 656         struct inode_record *rec;
 657         struct inode_backref *backref;
 658         struct inode_backref *orig;
 659         struct inode_backref *tmp;
 660         struct orphan_data_extent *src_orphan;
 661         struct orphan_data_extent *dst_orphan;
 662         struct rb_node *rb;
 663         size_t size;
 664         int ret;
 665
 666         rec = malloc(sizeof(*rec));
 667         if (!rec)
 668                 return ERR_PTR(-ENOMEM);
 669         memcpy(rec, orig_rec, sizeof(*rec));
 670         rec->refs = 1;
 671         INIT_LIST_HEAD(&rec->backrefs);
 672         INIT_LIST_HEAD(&rec->orphan_extents);
 673         rec->holes = RB_ROOT;
 674
 675         list_for_each_entry(orig, &orig_rec->backrefs, list) {
 676                 size = sizeof(*orig) + orig->namelen + 1;
 677                 backref = malloc(size);
 678                 if (!backref) {
 679                         ret = -ENOMEM;
 680                         goto cleanup;
 681                 }
 682                 memcpy(backref, orig, size);
 683                 list_add_tail(&backref->list, &rec->backrefs);
 684         }
 685         list_for_each_entry(src_orphan, &orig_rec->orphan_extents, list) {
 686                 dst_orphan = malloc(sizeof(*dst_orphan));
 687                 if (!dst_orphan) {
 688                         ret = -ENOMEM;
 689                         goto cleanup;
 690                 }
 691                 memcpy(dst_orphan, src_orphan, sizeof(*src_orphan));
 692                 list_add_tail(&dst_orphan->list, &rec->orphan_extents);
 693         }
 694         ret = copy_file_extent_holes(&rec->holes, &orig_rec->holes);
 695         if (ret < 0)
 696                 goto cleanup_rb;
 697
 698         return rec;
 699
 700 cleanup_rb:
 701         rb = rb_first(&rec->holes);
 702         while (rb) {
 703                 struct file_extent_hole *hole;
 704
 705                 hole = rb_entry(rb, struct file_extent_hole, node);
 706                 rb = rb_next(rb);
 707                 free(hole);
 708         }
 709
 710 cleanup:
 711         if (!list_empty(&rec->backrefs))
 712                 list_for_each_entry_safe(orig, tmp, &rec->backrefs, list) {
 713                         list_del(&orig->list);
 714                         free(orig);
 715                 }
 716
 717         if (!list_empty(&rec->orphan_extents))
 718                 list_for_each_entry_safe(orig, tmp, &rec->orphan_extents, list) {
 719                         list_del(&orig->list);
 720                         free(orig);
 721                 }
 722
 723         free(rec);
 724
 725         return ERR_PTR(ret);
 726 }
 727
 728 static void print_orphan_data_extents(struct list_head *orphan_extents,
 729                                       u64 objectid)
 730 {
 731         struct orphan_data_extent *orphan;
 732
 733         if (list_empty(orphan_extents))
 734                 return;
 735         printf("The following data extent is lost in tree %llu:\n",
 736                objectid);
 737         list_for_each_entry(orphan, orphan_extents, list) {
 738                 printf("\tinode: %llu, offset:%llu, disk_bytenr: %llu, disk_len: %llu\n",
 739                        orphan->objectid, orphan->offset, orphan->disk_bytenr,
 740                        orphan->disk_len);
 741         }
 742 }
 743
 744 static void print_inode_error(struct btrfs_root *root, struct inode_record *rec)
 745 {
 746         u64 root_objectid = root->root_key.objectid;
 747         int errors = rec->errors;
 748
 749         if (!errors)
 750                 return;
 751         /* reloc root errors, we print its corresponding fs root objectid*/
 752         if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
 753                 root_objectid = root->root_key.offset;
 754                 fprintf(stderr, "reloc");
 755         }
 756         fprintf(stderr, "root %llu inode %llu errors %x",
 757                 (unsigned long long) root_objectid,
 758                 (unsigned long long) rec->ino, rec->errors);
 759
 760         if (errors & I_ERR_NO_INODE_ITEM)
 761                 fprintf(stderr, ", no inode item");
 762         if (errors & I_ERR_NO_ORPHAN_ITEM)
 763                 fprintf(stderr, ", no orphan item");
 764         if (errors & I_ERR_DUP_INODE_ITEM)
 765                 fprintf(stderr, ", dup inode item");
 766         if (errors & I_ERR_DUP_DIR_INDEX)
 767                 fprintf(stderr, ", dup dir index");
 768         if (errors & I_ERR_ODD_DIR_ITEM)
 769                 fprintf(stderr, ", odd dir item");
 770         if (errors & I_ERR_ODD_FILE_EXTENT)
 771                 fprintf(stderr, ", odd file extent");
 772         if (errors & I_ERR_BAD_FILE_EXTENT)
 773                 fprintf(stderr, ", bad file extent");
 774         if (errors & I_ERR_FILE_EXTENT_OVERLAP)
 775                 fprintf(stderr, ", file extent overlap");
 776         if (errors & I_ERR_FILE_EXTENT_DISCOUNT)
 777                 fprintf(stderr, ", file extent discount");
 778         if (errors & I_ERR_DIR_ISIZE_WRONG)
 779                 fprintf(stderr, ", dir isize wrong");
 780         if (errors & I_ERR_FILE_NBYTES_WRONG)
 781                 fprintf(stderr, ", nbytes wrong");
 782         if (errors & I_ERR_ODD_CSUM_ITEM)
 783                 fprintf(stderr, ", odd csum item");
 784         if (errors & I_ERR_SOME_CSUM_MISSING)
 785                 fprintf(stderr, ", some csum missing");
 786         if (errors & I_ERR_LINK_COUNT_WRONG)
 787                 fprintf(stderr, ", link count wrong");
 788         if (errors & I_ERR_FILE_EXTENT_ORPHAN)
 789                 fprintf(stderr, ", orphan file extent");
 790         fprintf(stderr, "\n");
 791         /* Print the orphan extents if needed */
 792         if (errors & I_ERR_FILE_EXTENT_ORPHAN)
 793                 print_orphan_data_extents(&rec->orphan_extents, root->objectid);
 794
 795         /* Print the holes if needed */
 796         if (errors & I_ERR_FILE_EXTENT_DISCOUNT) {
 797                 struct file_extent_hole *hole;
 798                 struct rb_node *node;
 799                 int found = 0;
 800
 801                 node = rb_first(&rec->holes);
 802                 fprintf(stderr, "Found file extent holes:\n");
 803                 while (node) {
 804                         found = 1;
 805                         hole = rb_entry(node, struct file_extent_hole, node);
 806                         fprintf(stderr, "\tstart: %llu, len: %llu\n",
 807                                 hole->start, hole->len);
 808                         node = rb_next(node);
 809                 }
 810                 if (!found)
 811                         fprintf(stderr, "\tstart: 0, len: %llu\n",
 812                                 round_up(rec->isize, root->sectorsize));
 813         }
 814 }
 815
 816 static void print_ref_error(int errors)
 817 {
 818         if (errors & REF_ERR_NO_DIR_ITEM)
 819                 fprintf(stderr, ", no dir item");
 820         if (errors & REF_ERR_NO_DIR_INDEX)
 821                 fprintf(stderr, ", no dir index");
 822         if (errors & REF_ERR_NO_INODE_REF)
 823                 fprintf(stderr, ", no inode ref");
 824         if (errors & REF_ERR_DUP_DIR_ITEM)
 825                 fprintf(stderr, ", dup dir item");
 826         if (errors & REF_ERR_DUP_DIR_INDEX)
 827                 fprintf(stderr, ", dup dir index");
 828         if (errors & REF_ERR_DUP_INODE_REF)
 829                 fprintf(stderr, ", dup inode ref");
 830         if (errors & REF_ERR_INDEX_UNMATCH)
 831                 fprintf(stderr, ", index mismatch");
 832         if (errors & REF_ERR_FILETYPE_UNMATCH)
 833                 fprintf(stderr, ", filetype mismatch");
 834         if (errors & REF_ERR_NAME_TOO_LONG)
 835                 fprintf(stderr, ", name too long");
 836         if (errors & REF_ERR_NO_ROOT_REF)
 837                 fprintf(stderr, ", no root ref");
 838         if (errors & REF_ERR_NO_ROOT_BACKREF)
 839                 fprintf(stderr, ", no root backref");
 840         if (errors & REF_ERR_DUP_ROOT_REF)
 841                 fprintf(stderr, ", dup root ref");
 842         if (errors & REF_ERR_DUP_ROOT_BACKREF)
 843                 fprintf(stderr, ", dup root backref");
 844         fprintf(stderr, "\n");
 845 }
 846
 847 static struct inode_record *get_inode_rec(struct cache_tree *inode_cache,
 848                                           u64 ino, int mod)
 849 {
 850         struct ptr_node *node;
 851         struct cache_extent *cache;
 852         struct inode_record *rec = NULL;
 853         int ret;
 854
 855         cache = lookup_cache_extent(inode_cache, ino, 1);
 856         if (cache) {
 857                 node = container_of(cache, struct ptr_node, cache);
 858                 rec = node->data;
 859                 if (mod && rec->refs > 1) {
 860                         node->data = clone_inode_rec(rec);
 861                         if (IS_ERR(node->data))
 862                                 return node->data;
 863                         rec->refs--;
 864                         rec = node->data;
 865                 }
 866         } else if (mod) {
 867                 rec = calloc(1, sizeof(*rec));
 868                 if (!rec)
 869                         return ERR_PTR(-ENOMEM);
 870                 rec->ino = ino;
 871                 rec->extent_start = (u64)-1;
 872                 rec->refs = 1;
 873                 INIT_LIST_HEAD(&rec->backrefs);
 874                 INIT_LIST_HEAD(&rec->orphan_extents);
 875                 rec->holes = RB_ROOT;
 876
 877                 node = malloc(sizeof(*node));
 878                 if (!node) {
 879                         free(rec);
 880                         return ERR_PTR(-ENOMEM);
 881                 }
 882                 node->cache.start = ino;
 883                 node->cache.size = 1;
 884                 node->data = rec;
 885
 886                 if (ino == BTRFS_FREE_INO_OBJECTID)
 887                         rec->found_link = 1;
 888
 889                 ret = insert_cache_extent(inode_cache, &node->cache);
 890                 if (ret)
 891                         return ERR_PTR(-EEXIST);
 892         }
 893         return rec;
 894 }
 895
 896 static void free_orphan_data_extents(struct list_head *orphan_extents)
 897 {
 898         struct orphan_data_extent *orphan;
 899
 900         while (!list_empty(orphan_extents)) {
 901                 orphan = list_entry(orphan_extents->next,
 902                                     struct orphan_data_extent, list);
 903                 list_del(&orphan->list);
 904                 free(orphan);
 905         }
 906 }
 907
 908 static void free_inode_rec(struct inode_record *rec)
 909 {
 910         struct inode_backref *backref;
 911
 912         if (--rec->refs > 0)
 913                 return;
 914
 915         while (!list_empty(&rec->backrefs)) {
 916                 backref = to_inode_backref(rec->backrefs.next);
 917                 list_del(&backref->list);
 918                 free(backref);
 919         }
 920         free_orphan_data_extents(&rec->orphan_extents);
 921         free_file_extent_holes(&rec->holes);
 922         free(rec);
 923 }
 924
 925 static int can_free_inode_rec(struct inode_record *rec)
 926 {
 927         if (!rec->errors && rec->checked && rec->found_inode_item &&
 928             rec->nlink == rec->found_link && list_empty(&rec->backrefs))
 929                 return 1;
 930         return 0;
 931 }
 932
 933 static void maybe_free_inode_rec(struct cache_tree *inode_cache,
 934                                  struct inode_record *rec)
 935 {
 936         struct cache_extent *cache;
 937         struct inode_backref *tmp, *backref;
 938         struct ptr_node *node;
 939         u8 filetype;
 940
 941         if (!rec->found_inode_item)
 942                 return;
 943
 944         filetype = imode_to_type(rec->imode);
 945         list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
 946                 if (backref->found_dir_item && backref->found_dir_index) {
 947                         if (backref->filetype != filetype)
 948                                 backref->errors |= REF_ERR_FILETYPE_UNMATCH;
 949                         if (!backref->errors && backref->found_inode_ref &&
 950                             rec->nlink == rec->found_link) {
 951                                 list_del(&backref->list);
 952                                 free(backref);
 953                         }
 954                 }
 955         }
 956
 957         if (!rec->checked || rec->merging)
 958                 return;
 959
 960         if (S_ISDIR(rec->imode)) {
 961                 if (rec->found_size != rec->isize)
 962                         rec->errors |= I_ERR_DIR_ISIZE_WRONG;
 963                 if (rec->found_file_extent)
 964                         rec->errors |= I_ERR_ODD_FILE_EXTENT;
 965         } else if (S_ISREG(rec->imode) || S_ISLNK(rec->imode)) {
 966                 if (rec->found_dir_item)
 967                         rec->errors |= I_ERR_ODD_DIR_ITEM;
 968                 if (rec->found_size != rec->nbytes)
 969                         rec->errors |= I_ERR_FILE_NBYTES_WRONG;
 970                 if (rec->nlink > 0 && !no_holes &&
 971                     (rec->extent_end < rec->isize ||
 972                      first_extent_gap(&rec->holes) < rec->isize))
 973                         rec->errors |= I_ERR_FILE_EXTENT_DISCOUNT;
 974         }
 975
 976         if (S_ISREG(rec->imode) || S_ISLNK(rec->imode)) {
 977                 if (rec->found_csum_item && rec->nodatasum)
 978                         rec->errors |= I_ERR_ODD_CSUM_ITEM;
 979                 if (rec->some_csum_missing && !rec->nodatasum)
 980                         rec->errors |= I_ERR_SOME_CSUM_MISSING;
 981         }
 982
 983         BUG_ON(rec->refs != 1);
 984         if (can_free_inode_rec(rec)) {
 985                 cache = lookup_cache_extent(inode_cache, rec->ino, 1);
 986                 node = container_of(cache, struct ptr_node, cache);
 987                 BUG_ON(node->data != rec);
 988                 remove_cache_extent(inode_cache, &node->cache);
 989                 free(node);
 990                 free_inode_rec(rec);
 991         }
 992 }
 993
 994 static int check_orphan_item(struct btrfs_root *root, u64 ino)
 995 {
 996         struct btrfs_path path;
 997         struct btrfs_key key;
 998         int ret;
 999
1000         key.objectid = BTRFS_ORPHAN_OBJECTID;
1001         key.type = BTRFS_ORPHAN_ITEM_KEY;
1002         key.offset = ino;
1003
1004         btrfs_init_path(&path);
1005         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
1006         btrfs_release_path(&path);
1007         if (ret > 0)
1008                 ret = -ENOENT;
1009         return ret;
1010 }
1011
1012 static int process_inode_item(struct extent_buffer *eb,
1013                               int slot, struct btrfs_key *key,
1014                               struct shared_node *active_node)
1015 {
1016         struct inode_record *rec;
1017         struct btrfs_inode_item *item;
1018
1019         rec = active_node->current;
1020         BUG_ON(rec->ino != key->objectid || rec->refs > 1);
1021         if (rec->found_inode_item) {
1022                 rec->errors |= I_ERR_DUP_INODE_ITEM;
1023                 return 1;
1024         }
1025         item = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
1026         rec->nlink = btrfs_inode_nlink(eb, item);
1027         rec->isize = btrfs_inode_size(eb, item);
1028         rec->nbytes = btrfs_inode_nbytes(eb, item);
1029         rec->imode = btrfs_inode_mode(eb, item);
1030         if (btrfs_inode_flags(eb, item) & BTRFS_INODE_NODATASUM)
1031                 rec->nodatasum = 1;
1032         rec->found_inode_item = 1;
1033         if (rec->nlink == 0)
1034                 rec->errors |= I_ERR_NO_ORPHAN_ITEM;
1035         maybe_free_inode_rec(&active_node->inode_cache, rec);
1036         return 0;
1037 }
1038
1039 static struct inode_backref *get_inode_backref(struct inode_record *rec,
1040                                                 const char *name,
1041                                                 int namelen, u64 dir)
1042 {
1043         struct inode_backref *backref;
1044
1045         list_for_each_entry(backref, &rec->backrefs, list) {
1046                 if (rec->ino == BTRFS_MULTIPLE_OBJECTIDS)
1047                         break;
1048                 if (backref->dir != dir || backref->namelen != namelen)
1049                         continue;
1050                 if (memcmp(name, backref->name, namelen))
1051                         continue;
1052                 return backref;
1053         }
1054
1055         backref = malloc(sizeof(*backref) + namelen + 1);
1056         if (!backref)
1057                 return NULL;
1058         memset(backref, 0, sizeof(*backref));
1059         backref->dir = dir;
1060         backref->namelen = namelen;
1061         memcpy(backref->name, name, namelen);
1062         backref->name[namelen] = '\0';
1063         list_add_tail(&backref->list, &rec->backrefs);
1064         return backref;
1065 }
1066
1067 static int add_inode_backref(struct cache_tree *inode_cache,
1068                              u64 ino, u64 dir, u64 index,
1069                              const char *name, int namelen,
1070                              u8 filetype, u8 itemtype, int errors)
1071 {
1072         struct inode_record *rec;
1073         struct inode_backref *backref;
1074
1075         rec = get_inode_rec(inode_cache, ino, 1);
1076         BUG_ON(IS_ERR(rec));
1077         backref = get_inode_backref(rec, name, namelen, dir);
1078         BUG_ON(!backref);
1079         if (errors)
1080                 backref->errors |= errors;
1081         if (itemtype == BTRFS_DIR_INDEX_KEY) {
1082                 if (backref->found_dir_index)
1083                         backref->errors |= REF_ERR_DUP_DIR_INDEX;
1084                 if (backref->found_inode_ref && backref->index != index)
1085                         backref->errors |= REF_ERR_INDEX_UNMATCH;
1086                 if (backref->found_dir_item && backref->filetype != filetype)
1087                         backref->errors |= REF_ERR_FILETYPE_UNMATCH;
1088
1089                 backref->index = index;
1090                 backref->filetype = filetype;
1091                 backref->found_dir_index = 1;
1092         } else if (itemtype == BTRFS_DIR_ITEM_KEY) {
1093                 rec->found_link++;
1094                 if (backref->found_dir_item)
1095                         backref->errors |= REF_ERR_DUP_DIR_ITEM;
1096                 if (backref->found_dir_index && backref->filetype != filetype)
1097                         backref->errors |= REF_ERR_FILETYPE_UNMATCH;
1098
1099                 backref->filetype = filetype;
1100                 backref->found_dir_item = 1;
1101         } else if ((itemtype == BTRFS_INODE_REF_KEY) ||
1102                    (itemtype == BTRFS_INODE_EXTREF_KEY)) {
1103                 if (backref->found_inode_ref)
1104                         backref->errors |= REF_ERR_DUP_INODE_REF;
1105                 if (backref->found_dir_index && backref->index != index)
1106                         backref->errors |= REF_ERR_INDEX_UNMATCH;
1107                 else
1108                         backref->index = index;
1109
1110                 backref->ref_type = itemtype;
1111                 backref->found_inode_ref = 1;
1112         } else {
1113                 BUG_ON(1);
1114         }
1115
1116         maybe_free_inode_rec(inode_cache, rec);
1117         return 0;
1118 }
1119
1120 static int merge_inode_recs(struct inode_record *src, struct inode_record *dst,
1121                             struct cache_tree *dst_cache)
1122 {
1123         struct inode_backref *backref;
1124         u32 dir_count = 0;
1125         int ret = 0;
1126
1127         dst->merging = 1;
1128         list_for_each_entry(backref, &src->backrefs, list) {
1129                 if (backref->found_dir_index) {
1130                         add_inode_backref(dst_cache, dst->ino, backref->dir,
1131                                         backref->index, backref->name,
1132                                         backref->namelen, backref->filetype,
1133                                         BTRFS_DIR_INDEX_KEY, backref->errors);
1134                 }
1135                 if (backref->found_dir_item) {
1136                         dir_count++;
1137                         add_inode_backref(dst_cache, dst->ino,
1138                                         backref->dir, 0, backref->name,
1139                                         backref->namelen, backref->filetype,
1140                                         BTRFS_DIR_ITEM_KEY, backref->errors);
1141                 }
1142                 if (backref->found_inode_ref) {
1143                         add_inode_backref(dst_cache, dst->ino,
1144                                         backref->dir, backref->index,
1145                                         backref->name, backref->namelen, 0,
1146                                         backref->ref_type, backref->errors);
1147                 }
1148         }
1149
1150         if (src->found_dir_item)
1151                 dst->found_dir_item = 1;
1152         if (src->found_file_extent)
1153                 dst->found_file_extent = 1;
1154         if (src->found_csum_item)
1155                 dst->found_csum_item = 1;
1156         if (src->some_csum_missing)
1157                 dst->some_csum_missing = 1;
1158         if (first_extent_gap(&dst->holes) > first_extent_gap(&src->holes)) {
1159                 ret = copy_file_extent_holes(&dst->holes, &src->holes);
1160                 if (ret < 0)
1161                         return ret;
1162         }
1163
1164         BUG_ON(src->found_link < dir_count);
1165         dst->found_link += src->found_link - dir_count;
1166         dst->found_size += src->found_size;
1167         if (src->extent_start != (u64)-1) {
1168                 if (dst->extent_start == (u64)-1) {
1169                         dst->extent_start = src->extent_start;
1170                         dst->extent_end = src->extent_end;
1171                 } else {
1172                         if (dst->extent_end > src->extent_start)
1173                                 dst->errors |= I_ERR_FILE_EXTENT_OVERLAP;
1174                         else if (dst->extent_end < src->extent_start) {
1175                                 ret = add_file_extent_hole(&dst->holes,
1176                                         dst->extent_end,
1177                                         src->extent_start - dst->extent_end);
1178                         }
1179                         if (dst->extent_end < src->extent_end)
1180                                 dst->extent_end = src->extent_end;
1181                 }
1182         }
1183
1184         dst->errors |= src->errors;
1185         if (src->found_inode_item) {
1186                 if (!dst->found_inode_item) {
1187                         dst->nlink = src->nlink;
1188                         dst->isize = src->isize;
1189                         dst->nbytes = src->nbytes;
1190                         dst->imode = src->imode;
1191                         dst->nodatasum = src->nodatasum;
1192                         dst->found_inode_item = 1;
1193                 } else {
1194                         dst->errors |= I_ERR_DUP_INODE_ITEM;
1195                 }
1196         }
1197         dst->merging = 0;
1198
1199         return 0;
1200 }
1201
1202 static int splice_shared_node(struct shared_node *src_node,
1203                               struct shared_node *dst_node)
1204 {
1205         struct cache_extent *cache;
1206         struct ptr_node *node, *ins;
1207         struct cache_tree *src, *dst;
1208         struct inode_record *rec, *conflict;
1209         u64 current_ino = 0;
1210         int splice = 0;
1211         int ret;
1212
1213         if (--src_node->refs == 0)
1214                 splice = 1;
1215         if (src_node->current)
1216                 current_ino = src_node->current->ino;
1217
1218         src = &src_node->root_cache;
1219         dst = &dst_node->root_cache;
1220 again:
1221         cache = search_cache_extent(src, 0);
1222         while (cache) {
1223                 node = container_of(cache, struct ptr_node, cache);
1224                 rec = node->data;
1225                 cache = next_cache_extent(cache);
1226
1227                 if (splice) {
1228                         remove_cache_extent(src, &node->cache);
1229                         ins = node;
1230                 } else {
1231                         ins = malloc(sizeof(*ins));
1232                         BUG_ON(!ins);
1233                         ins->cache.start = node->cache.start;
1234                         ins->cache.size = node->cache.size;
1235                         ins->data = rec;
1236                         rec->refs++;
1237                 }
1238                 ret = insert_cache_extent(dst, &ins->cache);
1239                 if (ret == -EEXIST) {
1240                         conflict = get_inode_rec(dst, rec->ino, 1);
1241                         BUG_ON(IS_ERR(conflict));
1242                         merge_inode_recs(rec, conflict, dst);
1243                         if (rec->checked) {
1244                                 conflict->checked = 1;
1245                                 if (dst_node->current == conflict)
1246                                         dst_node->current = NULL;
1247                         }
1248                         maybe_free_inode_rec(dst, conflict);
1249                         free_inode_rec(rec);
1250                         free(ins);
1251                 } else {
1252                         BUG_ON(ret);
1253                 }
1254         }
1255
1256         if (src == &src_node->root_cache) {
1257                 src = &src_node->inode_cache;
1258                 dst = &dst_node->inode_cache;
1259                 goto again;
1260         }
1261
1262         if (current_ino > 0 && (!dst_node->current ||
1263             current_ino > dst_node->current->ino)) {
1264                 if (dst_node->current) {
1265                         dst_node->current->checked = 1;
1266                         maybe_free_inode_rec(dst, dst_node->current);
1267                 }
1268                 dst_node->current = get_inode_rec(dst, current_ino, 1);
1269                 BUG_ON(IS_ERR(dst_node->current));
1270         }
1271         return 0;
1272 }
1273
1274 static void free_inode_ptr(struct cache_extent *cache)
1275 {
1276         struct ptr_node *node;
1277         struct inode_record *rec;
1278
1279         node = container_of(cache, struct ptr_node, cache);
1280         rec = node->data;
1281         free_inode_rec(rec);
1282         free(node);
1283 }
1284
1285 FREE_EXTENT_CACHE_BASED_TREE(inode_recs, free_inode_ptr);
1286
1287 static struct shared_node *find_shared_node(struct cache_tree *shared,
1288                                             u64 bytenr)
1289 {
1290         struct cache_extent *cache;
1291         struct shared_node *node;
1292
1293         cache = lookup_cache_extent(shared, bytenr, 1);
1294         if (cache) {
1295                 node = container_of(cache, struct shared_node, cache);
1296                 return node;
1297         }
1298         return NULL;
1299 }
1300
1301 static int add_shared_node(struct cache_tree *shared, u64 bytenr, u32 refs)
1302 {
1303         int ret;
1304         struct shared_node *node;
1305
1306         node = calloc(1, sizeof(*node));
1307         if (!node)
1308                 return -ENOMEM;
1309         node->cache.start = bytenr;
1310         node->cache.size = 1;
1311         cache_tree_init(&node->root_cache);
1312         cache_tree_init(&node->inode_cache);
1313         node->refs = refs;
1314
1315         ret = insert_cache_extent(shared, &node->cache);
1316
1317         return ret;
1318 }
1319
1320 static int enter_shared_node(struct btrfs_root *root, u64 bytenr, u32 refs,
1321                              struct walk_control *wc, int level)
1322 {
1323         struct shared_node *node;
1324         struct shared_node *dest;
1325         int ret;
1326
1327         if (level == wc->active_node)
1328                 return 0;
1329
1330         BUG_ON(wc->active_node <= level);
1331         node = find_shared_node(&wc->shared, bytenr);
1332         if (!node) {
1333                 ret = add_shared_node(&wc->shared, bytenr, refs);
1334                 BUG_ON(ret);
1335                 node = find_shared_node(&wc->shared, bytenr);
1336                 wc->nodes[level] = node;
1337                 wc->active_node = level;
1338                 return 0;
1339         }
1340
1341         if (wc->root_level == wc->active_node &&
1342             btrfs_root_refs(&root->root_item) == 0) {
1343                 if (--node->refs == 0) {
1344                         free_inode_recs_tree(&node->root_cache);
1345                         free_inode_recs_tree(&node->inode_cache);
1346                         remove_cache_extent(&wc->shared, &node->cache);
1347                         free(node);
1348                 }
1349                 return 1;
1350         }
1351
1352         dest = wc->nodes[wc->active_node];
1353         splice_shared_node(node, dest);
1354         if (node->refs == 0) {
1355                 remove_cache_extent(&wc->shared, &node->cache);
1356                 free(node);
1357         }
1358         return 1;
1359 }
1360
1361 static int leave_shared_node(struct btrfs_root *root,
1362                              struct walk_control *wc, int level)
1363 {
1364         struct shared_node *node;
1365         struct shared_node *dest;
1366         int i;
1367
1368         if (level == wc->root_level)
1369                 return 0;
1370
1371         for (i = level + 1; i < BTRFS_MAX_LEVEL; i++) {
1372                 if (wc->nodes[i])
1373                         break;
1374         }
1375         BUG_ON(i >= BTRFS_MAX_LEVEL);
1376
1377         node = wc->nodes[wc->active_node];
1378         wc->nodes[wc->active_node] = NULL;
1379         wc->active_node = i;
1380
1381         dest = wc->nodes[wc->active_node];
1382         if (wc->active_node < wc->root_level ||
1383             btrfs_root_refs(&root->root_item) > 0) {
1384                 BUG_ON(node->refs <= 1);
1385                 splice_shared_node(node, dest);
1386         } else {
1387                 BUG_ON(node->refs < 2);
1388                 node->refs--;
1389         }
1390         return 0;
1391 }
1392
1393 /*
1394  * Returns:
1395  * < 0 - on error
1396  * 1   - if the root with id child_root_id is a child of root parent_root_id
1397  * 0   - if the root child_root_id isn't a child of the root parent_root_id but
1398  *       has other root(s) as parent(s)
1399  * 2   - if the root child_root_id doesn't have any parent roots
1400  */
1401 static int is_child_root(struct btrfs_root *root, u64 parent_root_id,
1402                          u64 child_root_id)
1403 {
1404         struct btrfs_path path;
1405         struct btrfs_key key;
1406         struct extent_buffer *leaf;
1407         int has_parent = 0;
1408         int ret;
1409
1410         btrfs_init_path(&path);
1411
1412         key.objectid = parent_root_id;
1413         key.type = BTRFS_ROOT_REF_KEY;
1414         key.offset = child_root_id;
1415         ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, &path,
1416                                 0, 0);
1417         if (ret < 0)
1418                 return ret;
1419         btrfs_release_path(&path);
1420         if (!ret)
1421                 return 1;
1422
1423         key.objectid = child_root_id;
1424         key.type = BTRFS_ROOT_BACKREF_KEY;
1425         key.offset = 0;
1426         ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, &path,
1427                                 0, 0);
1428         if (ret < 0)
1429                 goto out;
1430
1431         while (1) {
1432                 leaf = path.nodes[0];
1433                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
1434                         ret = btrfs_next_leaf(root->fs_info->tree_root, &path);
1435                         if (ret)
1436                                 break;
1437                         leaf = path.nodes[0];
1438                 }
1439
1440                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1441                 if (key.objectid != child_root_id ||
1442                     key.type != BTRFS_ROOT_BACKREF_KEY)
1443                         break;
1444
1445                 has_parent = 1;
1446
1447                 if (key.offset == parent_root_id) {
1448                         btrfs_release_path(&path);
1449                         return 1;
1450                 }
1451
1452                 path.slots[0]++;
1453         }
1454 out:
1455         btrfs_release_path(&path);
1456         if (ret < 0)
1457                 return ret;
1458         return has_parent ? 0 : 2;
1459 }
1460
1461 static int process_dir_item(struct btrfs_root *root,
1462                             struct extent_buffer *eb,
1463                             int slot, struct btrfs_key *key,
1464                             struct shared_node *active_node)
1465 {
1466         u32 total;
1467         u32 cur = 0;
1468         u32 len;
1469         u32 name_len;
1470         u32 data_len;
1471         int error;
1472         int nritems = 0;
1473         u8 filetype;
1474         struct btrfs_dir_item *di;
1475         struct inode_record *rec;
1476         struct cache_tree *root_cache;
1477         struct cache_tree *inode_cache;
1478         struct btrfs_key location;
1479         char namebuf[BTRFS_NAME_LEN];
1480
1481         root_cache = &active_node->root_cache;
1482         inode_cache = &active_node->inode_cache;
1483         rec = active_node->current;
1484         rec->found_dir_item = 1;
1485
1486         di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
1487         total = btrfs_item_size_nr(eb, slot);
1488         while (cur < total) {
1489                 nritems++;
1490                 btrfs_dir_item_key_to_cpu(eb, di, &location);
1491                 name_len = btrfs_dir_name_len(eb, di);
1492                 data_len = btrfs_dir_data_len(eb, di);
1493                 filetype = btrfs_dir_type(eb, di);
1494
1495                 rec->found_size += name_len;
1496                 if (name_len <= BTRFS_NAME_LEN) {
1497                         len = name_len;
1498                         error = 0;
1499                 } else {
1500                         len = BTRFS_NAME_LEN;
1501                         error = REF_ERR_NAME_TOO_LONG;
1502                 }
1503                 read_extent_buffer(eb, namebuf, (unsigned long)(di + 1), len);
1504
1505                 if (location.type == BTRFS_INODE_ITEM_KEY) {
1506                         add_inode_backref(inode_cache, location.objectid,
1507                                           key->objectid, key->offset, namebuf,
1508                                           len, filetype, key->type, error);
1509                 } else if (location.type == BTRFS_ROOT_ITEM_KEY) {
1510                         add_inode_backref(root_cache, location.objectid,
1511                                           key->objectid, key->offset,
1512                                           namebuf, len, filetype,
1513                                           key->type, error);
1514                 } else {
1515                         fprintf(stderr, "invalid location in dir item %u\n",
1516                                 location.type);
1517                         add_inode_backref(inode_cache, BTRFS_MULTIPLE_OBJECTIDS,
1518                                           key->objectid, key->offset, namebuf,
1519                                           len, filetype, key->type, error);
1520                 }
1521
1522                 len = sizeof(*di) + name_len + data_len;
1523                 di = (struct btrfs_dir_item *)((char *)di + len);
1524                 cur += len;
1525         }
1526         if (key->type == BTRFS_DIR_INDEX_KEY && nritems > 1)
1527                 rec->errors |= I_ERR_DUP_DIR_INDEX;
1528
1529         return 0;
1530 }
1531
1532 static int process_inode_ref(struct extent_buffer *eb,
1533                              int slot, struct btrfs_key *key,
1534                              struct shared_node *active_node)
1535 {
1536         u32 total;
1537         u32 cur = 0;
1538         u32 len;
1539         u32 name_len;
1540         u64 index;
1541         int error;
1542         struct cache_tree *inode_cache;
1543         struct btrfs_inode_ref *ref;
1544         char namebuf[BTRFS_NAME_LEN];
1545
1546         inode_cache = &active_node->inode_cache;
1547
1548         ref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref);
1549         total = btrfs_item_size_nr(eb, slot);
1550         while (cur < total) {
1551                 name_len = btrfs_inode_ref_name_len(eb, ref);
1552                 index = btrfs_inode_ref_index(eb, ref);
1553                 if (name_len <= BTRFS_NAME_LEN) {
1554                         len = name_len;
1555                         error = 0;
1556                 } else {
1557                         len = BTRFS_NAME_LEN;
1558                         error = REF_ERR_NAME_TOO_LONG;
1559                 }
1560                 read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
1561                 add_inode_backref(inode_cache, key->objectid, key->offset,
1562                                   index, namebuf, len, 0, key->type, error);
1563
1564                 len = sizeof(*ref) + name_len;
1565                 ref = (struct btrfs_inode_ref *)((char *)ref + len);
1566                 cur += len;
1567         }
1568         return 0;
1569 }
1570
1571 static int process_inode_extref(struct extent_buffer *eb,
1572                                 int slot, struct btrfs_key *key,
1573                                 struct shared_node *active_node)
1574 {
1575         u32 total;
1576         u32 cur = 0;
1577         u32 len;
1578         u32 name_len;
1579         u64 index;
1580         u64 parent;
1581         int error;
1582         struct cache_tree *inode_cache;
1583         struct btrfs_inode_extref *extref;
1584         char namebuf[BTRFS_NAME_LEN];
1585
1586         inode_cache = &active_node->inode_cache;
1587
1588         extref = btrfs_item_ptr(eb, slot, struct btrfs_inode_extref);
1589         total = btrfs_item_size_nr(eb, slot);
1590         while (cur < total) {
1591                 name_len = btrfs_inode_extref_name_len(eb, extref);
1592                 index = btrfs_inode_extref_index(eb, extref);
1593                 parent = btrfs_inode_extref_parent(eb, extref);
1594                 if (name_len <= BTRFS_NAME_LEN) {
1595                         len = name_len;
1596                         error = 0;
1597                 } else {
1598                         len = BTRFS_NAME_LEN;
1599                         error = REF_ERR_NAME_TOO_LONG;
1600                 }
1601                 read_extent_buffer(eb, namebuf,
1602                                    (unsigned long)(extref + 1), len);
1603                 add_inode_backref(inode_cache, key->objectid, parent,
1604                                   index, namebuf, len, 0, key->type, error);
1605
1606                 len = sizeof(*extref) + name_len;
1607                 extref = (struct btrfs_inode_extref *)((char *)extref + len);
1608                 cur += len;
1609         }
1610         return 0;
1611
1612 }
1613
1614 static int count_csum_range(struct btrfs_root *root, u64 start,
1615                             u64 len, u64 *found)
1616 {
1617         struct btrfs_key key;
1618         struct btrfs_path path;
1619         struct extent_buffer *leaf;
1620         int ret;
1621         size_t size;
1622         *found = 0;
1623         u64 csum_end;
1624         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
1625
1626         btrfs_init_path(&path);
1627
1628         key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
1629         key.offset = start;
1630         key.type = BTRFS_EXTENT_CSUM_KEY;
1631
1632         ret = btrfs_search_slot(NULL, root->fs_info->csum_root,
1633                                 &key, &path, 0, 0);
1634         if (ret < 0)
1635                 goto out;
1636         if (ret > 0 && path.slots[0] > 0) {
1637                 leaf = path.nodes[0];
1638                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0] - 1);
1639                 if (key.objectid == BTRFS_EXTENT_CSUM_OBJECTID &&
1640                     key.type == BTRFS_EXTENT_CSUM_KEY)
1641                         path.slots[0]--;
1642         }
1643
1644         while (len > 0) {
1645                 leaf = path.nodes[0];
1646                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
1647                         ret = btrfs_next_leaf(root->fs_info->csum_root, &path);
1648                         if (ret > 0)
1649                                 break;
1650                         else if (ret < 0)
1651                                 goto out;
1652                         leaf = path.nodes[0];
1653                 }
1654
1655                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1656                 if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
1657                     key.type != BTRFS_EXTENT_CSUM_KEY)
1658                         break;
1659
1660                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1661                 if (key.offset >= start + len)
1662                         break;
1663
1664                 if (key.offset > start)
1665                         start = key.offset;
1666
1667                 size = btrfs_item_size_nr(leaf, path.slots[0]);
1668                 csum_end = key.offset + (size / csum_size) * root->sectorsize;
1669                 if (csum_end > start) {
1670                         size = min(csum_end - start, len);
1671                         len -= size;
1672                         start += size;
1673                         *found += size;
1674                 }
1675
1676                 path.slots[0]++;
1677         }
1678 out:
1679         btrfs_release_path(&path);
1680         if (ret < 0)
1681                 return ret;
1682         return 0;
1683 }
1684
1685 static int process_file_extent(struct btrfs_root *root,
1686                                 struct extent_buffer *eb,
1687                                 int slot, struct btrfs_key *key,
1688                                 struct shared_node *active_node)
1689 {
1690         struct inode_record *rec;
1691         struct btrfs_file_extent_item *fi;
1692         u64 num_bytes = 0;
1693         u64 disk_bytenr = 0;
1694         u64 extent_offset = 0;
1695         u64 mask = root->sectorsize - 1;
1696         int extent_type;
1697         int ret;
1698
1699         rec = active_node->current;
1700         BUG_ON(rec->ino != key->objectid || rec->refs > 1);
1701         rec->found_file_extent = 1;
1702
1703         if (rec->extent_start == (u64)-1) {
1704                 rec->extent_start = key->offset;
1705                 rec->extent_end = key->offset;
1706         }
1707
1708         if (rec->extent_end > key->offset)
1709                 rec->errors |= I_ERR_FILE_EXTENT_OVERLAP;
1710         else if (rec->extent_end < key->offset) {
1711                 ret = add_file_extent_hole(&rec->holes, rec->extent_end,
1712                                            key->offset - rec->extent_end);
1713                 if (ret < 0)
1714                         return ret;
1715         }
1716
1717         fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
1718         extent_type = btrfs_file_extent_type(eb, fi);
1719
1720         if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1721                 num_bytes = btrfs_file_extent_inline_len(eb, slot, fi);
1722                 if (num_bytes == 0)
1723                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1724                 rec->found_size += num_bytes;
1725                 num_bytes = (num_bytes + mask) & ~mask;
1726         } else if (extent_type == BTRFS_FILE_EXTENT_REG ||
1727                    extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1728                 num_bytes = btrfs_file_extent_num_bytes(eb, fi);
1729                 disk_bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
1730                 extent_offset = btrfs_file_extent_offset(eb, fi);
1731                 if (num_bytes == 0 || (num_bytes & mask))
1732                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1733                 if (num_bytes + extent_offset >
1734                     btrfs_file_extent_ram_bytes(eb, fi))
1735                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1736                 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC &&
1737                     (btrfs_file_extent_compression(eb, fi) ||
1738                      btrfs_file_extent_encryption(eb, fi) ||
1739                      btrfs_file_extent_other_encoding(eb, fi)))
1740                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1741                 if (disk_bytenr > 0)
1742                         rec->found_size += num_bytes;
1743         } else {
1744                 rec->errors |= I_ERR_BAD_FILE_EXTENT;
1745         }
1746         rec->extent_end = key->offset + num_bytes;
1747
1748         /*
1749          * The data reloc tree will copy full extents into its inode and then
1750          * copy the corresponding csums.  Because the extent it copied could be
1751          * a preallocated extent that hasn't been written to yet there may be no
1752          * csums to copy, ergo we won't have csums for our file extent.  This is
1753          * ok so just don't bother checking csums if the inode belongs to the
1754          * data reloc tree.
1755          */
1756         if (disk_bytenr > 0 &&
1757             btrfs_header_owner(eb) != BTRFS_DATA_RELOC_TREE_OBJECTID) {
1758                 u64 found;
1759                 if (btrfs_file_extent_compression(eb, fi))
1760                         num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
1761                 else
1762                         disk_bytenr += extent_offset;
1763
1764                 ret = count_csum_range(root, disk_bytenr, num_bytes, &found);
1765                 if (ret < 0)
1766                         return ret;
1767                 if (extent_type == BTRFS_FILE_EXTENT_REG) {
1768                         if (found > 0)
1769                                 rec->found_csum_item = 1;
1770                         if (found < num_bytes)
1771                                 rec->some_csum_missing = 1;
1772                 } else if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1773                         if (found > 0)
1774                                 rec->errors |= I_ERR_ODD_CSUM_ITEM;
1775                 }
1776         }
1777         return 0;
1778 }
1779
1780 static int process_one_leaf(struct btrfs_root *root, struct extent_buffer *eb,
1781                             struct walk_control *wc)
1782 {
1783         struct btrfs_key key;
1784         u32 nritems;
1785         int i;
1786         int ret = 0;
1787         struct cache_tree *inode_cache;
1788         struct shared_node *active_node;
1789
1790         if (wc->root_level == wc->active_node &&
1791             btrfs_root_refs(&root->root_item) == 0)
1792                 return 0;
1793
1794         active_node = wc->nodes[wc->active_node];
1795         inode_cache = &active_node->inode_cache;
1796         nritems = btrfs_header_nritems(eb);
1797         for (i = 0; i < nritems; i++) {
1798                 btrfs_item_key_to_cpu(eb, &key, i);
1799
1800                 if (key.objectid == BTRFS_FREE_SPACE_OBJECTID)
1801                         continue;
1802                 if (key.type == BTRFS_ORPHAN_ITEM_KEY)
1803                         continue;
1804
1805                 if (active_node->current == NULL ||
1806                     active_node->current->ino < key.objectid) {
1807                         if (active_node->current) {
1808                                 active_node->current->checked = 1;
1809                                 maybe_free_inode_rec(inode_cache,
1810                                                      active_node->current);
1811                         }
1812                         active_node->current = get_inode_rec(inode_cache,
1813                                                              key.objectid, 1);
1814                         BUG_ON(IS_ERR(active_node->current));
1815                 }
1816                 switch (key.type) {
1817                 case BTRFS_DIR_ITEM_KEY:
1818                 case BTRFS_DIR_INDEX_KEY:
1819                         ret = process_dir_item(root, eb, i, &key, active_node);
1820                         break;
1821                 case BTRFS_INODE_REF_KEY:
1822                         ret = process_inode_ref(eb, i, &key, active_node);
1823                         break;
1824                 case BTRFS_INODE_EXTREF_KEY:
1825                         ret = process_inode_extref(eb, i, &key, active_node);
1826                         break;
1827                 case BTRFS_INODE_ITEM_KEY:
1828                         ret = process_inode_item(eb, i, &key, active_node);
1829                         break;
1830                 case BTRFS_EXTENT_DATA_KEY:
1831                         ret = process_file_extent(root, eb, i, &key,
1832                                                   active_node);
1833                         break;
1834                 default:
1835                         break;
1836                 };
1837         }
1838         return ret;
1839 }
1840
1841 static void reada_walk_down(struct btrfs_root *root,
1842                             struct extent_buffer *node, int slot)
1843 {
1844         u64 bytenr;
1845         u64 ptr_gen;
1846         u32 nritems;
1847         u32 blocksize;
1848         int i;
1849         int level;
1850
1851         level = btrfs_header_level(node);
1852         if (level != 1)
1853                 return;
1854
1855         nritems = btrfs_header_nritems(node);
1856         blocksize = root->nodesize;
1857         for (i = slot; i < nritems; i++) {
1858                 bytenr = btrfs_node_blockptr(node, i);
1859                 ptr_gen = btrfs_node_ptr_generation(node, i);
1860                 readahead_tree_block(root, bytenr, blocksize, ptr_gen);
1861         }
1862 }
1863
1864 /*
1865  * Check the child node/leaf by the following condition:
1866  * 1. the first item key of the node/leaf should be the same with the one
1867  *    in parent.
1868  * 2. block in parent node should match the child node/leaf.
1869  * 3. generation of parent node and child's header should be consistent.
1870  *
1871  * Or the child node/leaf pointed by the key in parent is not valid.
1872  *
1873  * We hope to check leaf owner too, but since subvol may share leaves,
1874  * which makes leaf owner check not so strong, key check should be
1875  * sufficient enough for that case.
1876  */
1877 static int check_child_node(struct btrfs_root *root,
1878                             struct extent_buffer *parent, int slot,
1879                             struct extent_buffer *child)
1880 {
1881         struct btrfs_key parent_key;
1882         struct btrfs_key child_key;
1883         int ret = 0;
1884
1885         btrfs_node_key_to_cpu(parent, &parent_key, slot);
1886         if (btrfs_header_level(child) == 0)
1887                 btrfs_item_key_to_cpu(child, &child_key, 0);
1888         else
1889                 btrfs_node_key_to_cpu(child, &child_key, 0);
1890
1891         if (memcmp(&parent_key, &child_key, sizeof(parent_key))) {
1892                 ret = -EINVAL;
1893                 fprintf(stderr,
1894                         "Wrong key of child node/leaf, wanted: (%llu, %u, %llu), have: (%llu, %u, %llu)\n",
1895                         parent_key.objectid, parent_key.type, parent_key.offset,
1896                         child_key.objectid, child_key.type, child_key.offset);
1897         }
1898         if (btrfs_header_bytenr(child) != btrfs_node_blockptr(parent, slot)) {
1899                 ret = -EINVAL;
1900                 fprintf(stderr, "Wrong block of child node/leaf, wanted: %llu, have: %llu\n",
1901                         btrfs_node_blockptr(parent, slot),
1902                         btrfs_header_bytenr(child));
1903         }
1904         if (btrfs_node_ptr_generation(parent, slot) !=
1905             btrfs_header_generation(child)) {
1906                 ret = -EINVAL;
1907                 fprintf(stderr, "Wrong generation of child node/leaf, wanted: %llu, have: %llu\n",
1908                         btrfs_header_generation(child),
1909                         btrfs_node_ptr_generation(parent, slot));
1910         }
1911         return ret;
1912 }
1913
1914 struct node_refs {
1915         u64 bytenr[BTRFS_MAX_LEVEL];
1916         u64 refs[BTRFS_MAX_LEVEL];
1917 };
1918
1919 static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
1920                           struct walk_control *wc, int *level,
1921                           struct node_refs *nrefs)
1922 {
1923         enum btrfs_tree_block_status status;
1924         u64 bytenr;
1925         u64 ptr_gen;
1926         struct extent_buffer *next;
1927         struct extent_buffer *cur;
1928         u32 blocksize;
1929         int ret, err = 0;
1930         u64 refs;
1931
1932         WARN_ON(*level < 0);
1933         WARN_ON(*level >= BTRFS_MAX_LEVEL);
1934
1935         if (path->nodes[*level]->start == nrefs->bytenr[*level]) {
1936                 refs = nrefs->refs[*level];
1937                 ret = 0;
1938         } else {
1939                 ret = btrfs_lookup_extent_info(NULL, root,
1940                                        path->nodes[*level]->start,
1941                                        *level, 1, &refs, NULL);
1942                 if (ret < 0) {
1943                         err = ret;
1944                         goto out;
1945                 }
1946                 nrefs->bytenr[*level] = path->nodes[*level]->start;
1947                 nrefs->refs[*level] = refs;
1948         }
1949
1950         if (refs > 1) {
1951                 ret = enter_shared_node(root, path->nodes[*level]->start,
1952                                         refs, wc, *level);
1953                 if (ret > 0) {
1954                         err = ret;
1955                         goto out;
1956                 }
1957         }
1958
1959         while (*level >= 0) {
1960                 WARN_ON(*level < 0);
1961                 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1962                 cur = path->nodes[*level];
1963
1964                 if (btrfs_header_level(cur) != *level)
1965                         WARN_ON(1);
1966
1967                 if (path->slots[*level] >= btrfs_header_nritems(cur))
1968                         break;
1969                 if (*level == 0) {
1970                         ret = process_one_leaf(root, cur, wc);
1971                         if (ret < 0)
1972                                 err = ret;
1973                         break;
1974                 }
1975                 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1976                 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1977                 blocksize = root->nodesize;
1978
1979                 if (bytenr == nrefs->bytenr[*level - 1]) {
1980                         refs = nrefs->refs[*level - 1];
1981                 } else {
1982                         ret = btrfs_lookup_extent_info(NULL, root, bytenr,
1983                                         *level - 1, 1, &refs, NULL);
1984                         if (ret < 0) {
1985                                 refs = 0;
1986                         } else {
1987                                 nrefs->bytenr[*level - 1] = bytenr;
1988                                 nrefs->refs[*level - 1] = refs;
1989                         }
1990                 }
1991
1992                 if (refs > 1) {
1993                         ret = enter_shared_node(root, bytenr, refs,
1994                                                 wc, *level - 1);
1995                         if (ret > 0) {
1996                                 path->slots[*level]++;
1997                                 continue;
1998                         }
1999                 }
2000
2001                 next = btrfs_find_tree_block(root, bytenr, blocksize);
2002                 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
2003                         free_extent_buffer(next);
2004                         reada_walk_down(root, cur, path->slots[*level]);
2005                         next = read_tree_block(root, bytenr, blocksize,
2006                                                ptr_gen);
2007                         if (!extent_buffer_uptodate(next)) {
2008                                 struct btrfs_key node_key;
2009
2010                                 btrfs_node_key_to_cpu(path->nodes[*level],
2011                                                       &node_key,
2012                                                       path->slots[*level]);
2013                                 btrfs_add_corrupt_extent_record(root->fs_info,
2014                                                 &node_key,
2015                                                 path->nodes[*level]->start,
2016                                                 root->nodesize, *level);
2017                                 err = -EIO;
2018                                 goto out;
2019                         }
2020                 }
2021
2022                 ret = check_child_node(root, cur, path->slots[*level], next);
2023                 if (ret) {
2024                         err = ret;
2025                         goto out;
2026                 }
2027
2028                 if (btrfs_is_leaf(next))
2029                         status = btrfs_check_leaf(root, NULL, next);
2030                 else
2031                         status = btrfs_check_node(root, NULL, next);
2032                 if (status != BTRFS_TREE_BLOCK_CLEAN) {
2033                         free_extent_buffer(next);
2034                         err = -EIO;
2035                         goto out;
2036                 }
2037
2038                 *level = *level - 1;
2039                 free_extent_buffer(path->nodes[*level]);
2040                 path->nodes[*level] = next;
2041                 path->slots[*level] = 0;
2042         }
2043 out:
2044         path->slots[*level] = btrfs_header_nritems(path->nodes[*level]);
2045         return err;
2046 }
2047
2048 static int walk_up_tree(struct btrfs_root *root, struct btrfs_path *path,
2049                         struct walk_control *wc, int *level)
2050 {
2051         int i;
2052         struct extent_buffer *leaf;
2053
2054         for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
2055                 leaf = path->nodes[i];
2056                 if (path->slots[i] + 1 < btrfs_header_nritems(leaf)) {
2057                         path->slots[i]++;
2058                         *level = i;
2059                         return 0;
2060                 } else {
2061                         free_extent_buffer(path->nodes[*level]);
2062                         path->nodes[*level] = NULL;
2063                         BUG_ON(*level > wc->active_node);
2064                         if (*level == wc->active_node)
2065                                 leave_shared_node(root, wc, *level);
2066                         *level = i + 1;
2067                 }
2068         }
2069         return 1;
2070 }
2071
2072 static int check_root_dir(struct inode_record *rec)
2073 {
2074         struct inode_backref *backref;
2075         int ret = -1;
2076
2077         if (!rec->found_inode_item || rec->errors)
2078                 goto out;
2079         if (rec->nlink != 1 || rec->found_link != 0)
2080                 goto out;
2081         if (list_empty(&rec->backrefs))
2082                 goto out;
2083         backref = to_inode_backref(rec->backrefs.next);
2084         if (!backref->found_inode_ref)
2085                 goto out;
2086         if (backref->index != 0 || backref->namelen != 2 ||
2087             memcmp(backref->name, "..", 2))
2088                 goto out;
2089         if (backref->found_dir_index || backref->found_dir_item)
2090                 goto out;
2091         ret = 0;
2092 out:
2093         return ret;
2094 }
2095
2096 static int repair_inode_isize(struct btrfs_trans_handle *trans,
2097                               struct btrfs_root *root, struct btrfs_path *path,
2098                               struct inode_record *rec)
2099 {
2100         struct btrfs_inode_item *ei;
2101         struct btrfs_key key;
2102         int ret;
2103
2104         key.objectid = rec->ino;
2105         key.type = BTRFS_INODE_ITEM_KEY;
2106         key.offset = (u64)-1;
2107
2108         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2109         if (ret < 0)
2110                 goto out;
2111         if (ret) {
2112                 if (!path->slots[0]) {
2113                         ret = -ENOENT;
2114                         goto out;
2115                 }
2116                 path->slots[0]--;
2117                 ret = 0;
2118         }
2119         btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2120         if (key.objectid != rec->ino) {
2121                 ret = -ENOENT;
2122                 goto out;
2123         }
2124
2125         ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
2126                             struct btrfs_inode_item);
2127         btrfs_set_inode_size(path->nodes[0], ei, rec->found_size);
2128         btrfs_mark_buffer_dirty(path->nodes[0]);
2129         rec->errors &= ~I_ERR_DIR_ISIZE_WRONG;
2130         printf("reset isize for dir %Lu root %Lu\n", rec->ino,
2131                root->root_key.objectid);
2132 out:
2133         btrfs_release_path(path);
2134         return ret;
2135 }
2136
2137 static int repair_inode_orphan_item(struct btrfs_trans_handle *trans,
2138                                     struct btrfs_root *root,
2139                                     struct btrfs_path *path,
2140                                     struct inode_record *rec)
2141 {
2142         int ret;
2143
2144         ret = btrfs_add_orphan_item(trans, root, path, rec->ino);
2145         btrfs_release_path(path);
2146         if (!ret)
2147                 rec->errors &= ~I_ERR_NO_ORPHAN_ITEM;
2148         return ret;
2149 }
2150
2151 static int repair_inode_nbytes(struct btrfs_trans_handle *trans,
2152                                struct btrfs_root *root,
2153                                struct btrfs_path *path,
2154                                struct inode_record *rec)
2155 {
2156         struct btrfs_inode_item *ei;
2157         struct btrfs_key key;
2158         int ret = 0;
2159
2160         key.objectid = rec->ino;
2161         key.type = BTRFS_INODE_ITEM_KEY;
2162         key.offset = 0;
2163
2164         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2165         if (ret) {
2166                 if (ret > 0)
2167                         ret = -ENOENT;
2168                 goto out;
2169         }
2170
2171         /* Since ret == 0, no need to check anything */
2172         ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
2173                             struct btrfs_inode_item);
2174         btrfs_set_inode_nbytes(path->nodes[0], ei, rec->found_size);
2175         btrfs_mark_buffer_dirty(path->nodes[0]);
2176         rec->errors &= ~I_ERR_FILE_NBYTES_WRONG;
2177         printf("reset nbytes for ino %llu root %llu\n",
2178                rec->ino, root->root_key.objectid);
2179 out:
2180         btrfs_release_path(path);
2181         return ret;
2182 }
2183
2184 static int add_missing_dir_index(struct btrfs_root *root,
2185                                  struct cache_tree *inode_cache,
2186                                  struct inode_record *rec,
2187                                  struct inode_backref *backref)
2188 {
2189         struct btrfs_path path;
2190         struct btrfs_trans_handle *trans;
2191         struct btrfs_dir_item *dir_item;
2192         struct extent_buffer *leaf;
2193         struct btrfs_key key;
2194         struct btrfs_disk_key disk_key;
2195         struct inode_record *dir_rec;
2196         unsigned long name_ptr;
2197         u32 data_size = sizeof(*dir_item) + backref->namelen;
2198         int ret;
2199
2200         trans = btrfs_start_transaction(root, 1);
2201         if (IS_ERR(trans))
2202                 return PTR_ERR(trans);
2203
2204         fprintf(stderr, "repairing missing dir index item for inode %llu\n",
2205                 (unsigned long long)rec->ino);
2206
2207         btrfs_init_path(&path);
2208         key.objectid = backref->dir;
2209         key.type = BTRFS_DIR_INDEX_KEY;
2210         key.offset = backref->index;
2211         ret = btrfs_insert_empty_item(trans, root, &path, &key, data_size);
2212         BUG_ON(ret);
2213
2214         leaf = path.nodes[0];
2215         dir_item = btrfs_item_ptr(leaf, path.slots[0], struct btrfs_dir_item);
2216
2217         disk_key.objectid = cpu_to_le64(rec->ino);
2218         disk_key.type = BTRFS_INODE_ITEM_KEY;
2219         disk_key.offset = 0;
2220
2221         btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
2222         btrfs_set_dir_type(leaf, dir_item, imode_to_type(rec->imode));
2223         btrfs_set_dir_data_len(leaf, dir_item, 0);
2224         btrfs_set_dir_name_len(leaf, dir_item, backref->namelen);
2225         name_ptr = (unsigned long)(dir_item + 1);
2226         write_extent_buffer(leaf, backref->name, name_ptr, backref->namelen);
2227         btrfs_mark_buffer_dirty(leaf);
2228         btrfs_release_path(&path);
2229         btrfs_commit_transaction(trans, root);
2230
2231         backref->found_dir_index = 1;
2232         dir_rec = get_inode_rec(inode_cache, backref->dir, 0);
2233         BUG_ON(IS_ERR(dir_rec));
2234         if (!dir_rec)
2235                 return 0;
2236         dir_rec->found_size += backref->namelen;
2237         if (dir_rec->found_size == dir_rec->isize &&
2238             (dir_rec->errors & I_ERR_DIR_ISIZE_WRONG))
2239                 dir_rec->errors &= ~I_ERR_DIR_ISIZE_WRONG;
2240         if (dir_rec->found_size != dir_rec->isize)
2241                 dir_rec->errors |= I_ERR_DIR_ISIZE_WRONG;
2242
2243         return 0;
2244 }
2245
2246 static int delete_dir_index(struct btrfs_root *root,
2247                             struct cache_tree *inode_cache,
2248                             struct inode_record *rec,
2249                             struct inode_backref *backref)
2250 {
2251         struct btrfs_trans_handle *trans;
2252         struct btrfs_dir_item *di;
2253         struct btrfs_path path;
2254         int ret = 0;
2255
2256         trans = btrfs_start_transaction(root, 1);
2257         if (IS_ERR(trans))
2258                 return PTR_ERR(trans);
2259
2260         fprintf(stderr, "Deleting bad dir index [%llu,%u,%llu] root %llu\n",
2261                 (unsigned long long)backref->dir,
2262                 BTRFS_DIR_INDEX_KEY, (unsigned long long)backref->index,
2263                 (unsigned long long)root->objectid);
2264
2265         btrfs_init_path(&path);
2266         di = btrfs_lookup_dir_index(trans, root, &path, backref->dir,
2267                                     backref->name, backref->namelen,
2268                                     backref->index, -1);
2269         if (IS_ERR(di)) {
2270                 ret = PTR_ERR(di);
2271                 btrfs_release_path(&path);
2272                 btrfs_commit_transaction(trans, root);
2273                 if (ret == -ENOENT)
2274                         return 0;
2275                 return ret;
2276         }
2277
2278         if (!di)
2279                 ret = btrfs_del_item(trans, root, &path);
2280         else
2281                 ret = btrfs_delete_one_dir_name(trans, root, &path, di);
2282         BUG_ON(ret);
2283         btrfs_release_path(&path);
2284         btrfs_commit_transaction(trans, root);
2285         return ret;
2286 }
2287
2288 static int create_inode_item(struct btrfs_root *root,
2289                              struct inode_record *rec,
2290                              struct inode_backref *backref, int root_dir)
2291 {
2292         struct btrfs_trans_handle *trans;
2293         struct btrfs_inode_item inode_item;
2294         time_t now = time(NULL);
2295         int ret;
2296
2297         trans = btrfs_start_transaction(root, 1);
2298         if (IS_ERR(trans)) {
2299                 ret = PTR_ERR(trans);
2300                 return ret;
2301         }
2302
2303         fprintf(stderr, "root %llu inode %llu recreating inode item, this may "
2304                 "be incomplete, please check permissions and content after "
2305                 "the fsck completes.\n", (unsigned long long)root->objectid,
2306                 (unsigned long long)rec->ino);
2307
2308         memset(&inode_item, 0, sizeof(inode_item));
2309         btrfs_set_stack_inode_generation(&inode_item, trans->transid);
2310         if (root_dir)
2311                 btrfs_set_stack_inode_nlink(&inode_item, 1);
2312         else
2313                 btrfs_set_stack_inode_nlink(&inode_item, rec->found_link);
2314         btrfs_set_stack_inode_nbytes(&inode_item, rec->found_size);
2315         if (rec->found_dir_item) {
2316                 if (rec->found_file_extent)
2317                         fprintf(stderr, "root %llu inode %llu has both a dir "
2318                                 "item and extents, unsure if it is a dir or a "
2319                                 "regular file so setting it as a directory\n",
2320                                 (unsigned long long)root->objectid,
2321                                 (unsigned long long)rec->ino);
2322                 btrfs_set_stack_inode_mode(&inode_item, S_IFDIR | 0755);
2323                 btrfs_set_stack_inode_size(&inode_item, rec->found_size);
2324         } else if (!rec->found_dir_item) {
2325                 btrfs_set_stack_inode_size(&inode_item, rec->extent_end);
2326                 btrfs_set_stack_inode_mode(&inode_item, S_IFREG | 0755);
2327         }
2328         btrfs_set_stack_timespec_sec(&inode_item.atime, now);
2329         btrfs_set_stack_timespec_nsec(&inode_item.atime, 0);
2330         btrfs_set_stack_timespec_sec(&inode_item.ctime, now);
2331         btrfs_set_stack_timespec_nsec(&inode_item.ctime, 0);
2332         btrfs_set_stack_timespec_sec(&inode_item.mtime, now);
2333         btrfs_set_stack_timespec_nsec(&inode_item.mtime, 0);
2334         btrfs_set_stack_timespec_sec(&inode_item.otime, 0);
2335         btrfs_set_stack_timespec_nsec(&inode_item.otime, 0);
2336
2337         ret = btrfs_insert_inode(trans, root, rec->ino, &inode_item);
2338         BUG_ON(ret);
2339         btrfs_commit_transaction(trans, root);
2340         return 0;
2341 }
2342
2343 static int repair_inode_backrefs(struct btrfs_root *root,
2344                                  struct inode_record *rec,
2345                                  struct cache_tree *inode_cache,
2346                                  int delete)
2347 {
2348         struct inode_backref *tmp, *backref;
2349         u64 root_dirid = btrfs_root_dirid(&root->root_item);
2350         int ret = 0;
2351         int repaired = 0;
2352
2353         list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
2354                 if (!delete && rec->ino == root_dirid) {
2355                         if (!rec->found_inode_item) {
2356                                 ret = create_inode_item(root, rec, backref, 1);
2357                                 if (ret)
2358                                         break;
2359                                 repaired++;
2360                         }
2361                 }
2362
2363                 /* Index 0 for root dir's are special, don't mess with it */
2364                 if (rec->ino == root_dirid && backref->index == 0)
2365                         continue;
2366
2367                 if (delete &&
2368                     ((backref->found_dir_index && !backref->found_inode_ref) ||
2369                      (backref->found_dir_index && backref->found_inode_ref &&
2370                       (backref->errors & REF_ERR_INDEX_UNMATCH)))) {
2371                         ret = delete_dir_index(root, inode_cache, rec, backref);
2372                         if (ret)
2373                                 break;
2374                         repaired++;
2375                         list_del(&backref->list);
2376                         free(backref);
2377                 }
2378
2379                 if (!delete && !backref->found_dir_index &&
2380                     backref->found_dir_item && backref->found_inode_ref) {
2381                         ret = add_missing_dir_index(root, inode_cache, rec,
2382                                                     backref);
2383                         if (ret)
2384                                 break;
2385                         repaired++;
2386                         if (backref->found_dir_item &&
2387                             backref->found_dir_index &&
2388                             backref->found_dir_index) {
2389                                 if (!backref->errors &&
2390                                     backref->found_inode_ref) {
2391                                         list_del(&backref->list);
2392                                         free(backref);
2393                                 }
2394                         }
2395                 }
2396
2397                 if (!delete && (!backref->found_dir_index &&
2398                                 !backref->found_dir_item &&
2399                                 backref->found_inode_ref)) {
2400                         struct btrfs_trans_handle *trans;
2401                         struct btrfs_key location;
2402
2403                         ret = check_dir_conflict(root, backref->name,
2404                                                  backref->namelen,
2405                                                  backref->dir,
2406                                                  backref->index);
2407                         if (ret) {
2408                                 /*
2409                                  * let nlink fixing routine to handle it,
2410                                  * which can do it better.
2411                                  */
2412                                 ret = 0;
2413                                 break;
2414                         }
2415                         location.objectid = rec->ino;
2416                         location.type = BTRFS_INODE_ITEM_KEY;
2417                         location.offset = 0;
2418
2419                         trans = btrfs_start_transaction(root, 1);
2420                         if (IS_ERR(trans)) {
2421                                 ret = PTR_ERR(trans);
2422                                 break;
2423                         }
2424                         fprintf(stderr, "adding missing dir index/item pair "
2425                                 "for inode %llu\n",
2426                                 (unsigned long long)rec->ino);
2427                         ret = btrfs_insert_dir_item(trans, root, backref->name,
2428                                                     backref->namelen,
2429                                                     backref->dir, &location,
2430                                                     imode_to_type(rec->imode),
2431                                                     backref->index);
2432                         BUG_ON(ret);
2433                         btrfs_commit_transaction(trans, root);
2434                         repaired++;
2435                 }
2436
2437                 if (!delete && (backref->found_inode_ref &&
2438                                 backref->found_dir_index &&
2439                                 backref->found_dir_item &&
2440                                 !(backref->errors & REF_ERR_INDEX_UNMATCH) &&
2441                                 !rec->found_inode_item)) {
2442                         ret = create_inode_item(root, rec, backref, 0);
2443                         if (ret)
2444                                 break;
2445                         repaired++;
2446                 }
2447
2448         }
2449         return ret ? ret : repaired;
2450 }
2451
2452 /*
2453  * To determine the file type for nlink/inode_item repair
2454  *
2455  * Return 0 if file type is found and BTRFS_FT_* is stored into type.
2456  * Return -ENOENT if file type is not found.
2457  */
2458 static int find_file_type(struct inode_record *rec, u8 *type)
2459 {
2460         struct inode_backref *backref;
2461
2462         /* For inode item recovered case */
2463         if (rec->found_inode_item) {
2464                 *type = imode_to_type(rec->imode);
2465                 return 0;
2466         }
2467
2468         list_for_each_entry(backref, &rec->backrefs, list) {
2469                 if (backref->found_dir_index || backref->found_dir_item) {
2470                         *type = backref->filetype;
2471                         return 0;
2472                 }
2473         }
2474         return -ENOENT;
2475 }
2476
2477 /*
2478  * To determine the file name for nlink repair
2479  *
2480  * Return 0 if file name is found, set name and namelen.
2481  * Return -ENOENT if file name is not found.
2482  */
2483 static int find_file_name(struct inode_record *rec,
2484                           char *name, int *namelen)
2485 {
2486         struct inode_backref *backref;
2487
2488         list_for_each_entry(backref, &rec->backrefs, list) {
2489                 if (backref->found_dir_index || backref->found_dir_item ||
2490                     backref->found_inode_ref) {
2491                         memcpy(name, backref->name, backref->namelen);
2492                         *namelen = backref->namelen;
2493                         return 0;
2494                 }
2495         }
2496         return -ENOENT;
2497 }
2498
2499 /* Reset the nlink of the inode to the correct one */
2500 static int reset_nlink(struct btrfs_trans_handle *trans,
2501                        struct btrfs_root *root,
2502                        struct btrfs_path *path,
2503                        struct inode_record *rec)
2504 {
2505         struct inode_backref *backref;
2506         struct inode_backref *tmp;
2507         struct btrfs_key key;
2508         struct btrfs_inode_item *inode_item;
2509         int ret = 0;
2510
2511         /* We don't believe this either, reset it and iterate backref */
2512         rec->found_link = 0;
2513
2514         /* Remove all backref including the valid ones */
2515         list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
2516                 ret = btrfs_unlink(trans, root, rec->ino, backref->dir,
2517                                    backref->index, backref->name,
2518                                    backref->namelen, 0);
2519                 if (ret < 0)
2520                         goto out;
2521
2522                 /* remove invalid backref, so it won't be added back */
2523                 if (!(backref->found_dir_index &&
2524                       backref->found_dir_item &&
2525                       backref->found_inode_ref)) {
2526                         list_del(&backref->list);
2527                         free(backref);
2528                 } else {
2529                         rec->found_link++;
2530                 }
2531         }
2532
2533         /* Set nlink to 0 */
2534         key.objectid = rec->ino;
2535         key.type = BTRFS_INODE_ITEM_KEY;
2536         key.offset = 0;
2537         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2538         if (ret < 0)
2539                 goto out;
2540         if (ret > 0) {
2541                 ret = -ENOENT;
2542                 goto out;
2543         }
2544         inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2545                                     struct btrfs_inode_item);
2546         btrfs_set_inode_nlink(path->nodes[0], inode_item, 0);
2547         btrfs_mark_buffer_dirty(path->nodes[0]);
2548         btrfs_release_path(path);
2549
2550         /*
2551          * Add back valid inode_ref/dir_item/dir_index,
2552          * add_link() will handle the nlink inc, so new nlink must be correct
2553          */
2554         list_for_each_entry(backref, &rec->backrefs, list) {
2555                 ret = btrfs_add_link(trans, root, rec->ino, backref->dir,
2556                                      backref->name, backref->namelen,
2557                                      backref->filetype, &backref->index, 1);
2558                 if (ret < 0)
2559                         goto out;
2560         }
2561 out:
2562         btrfs_release_path(path);
2563         return ret;
2564 }
2565
2566 static int repair_inode_nlinks(struct btrfs_trans_handle *trans,
2567                                struct btrfs_root *root,
2568                                struct btrfs_path *path,
2569                                struct inode_record *rec)
2570 {
2571         char *dir_name = "lost+found";
2572         char namebuf[BTRFS_NAME_LEN] = {0};
2573         u64 lost_found_ino;
2574         u32 mode = 0700;
2575         u8 type = 0;
2576         int namelen = 0;
2577         int name_recovered = 0;
2578         int type_recovered = 0;
2579         int ret = 0;
2580
2581         /*
2582          * Get file name and type first before these invalid inode ref
2583          * are deleted by remove_all_invalid_backref()
2584          */
2585         name_recovered = !find_file_name(rec, namebuf, &namelen);
2586         type_recovered = !find_file_type(rec, &type);
2587
2588         if (!name_recovered) {
2589                 printf("Can't get file name for inode %llu, using '%llu' as fallback\n",
2590                        rec->ino, rec->ino);
2591                 namelen = count_digits(rec->ino);
2592                 sprintf(namebuf, "%llu", rec->ino);
2593                 name_recovered = 1;
2594         }
2595         if (!type_recovered) {
2596                 printf("Can't get file type for inode %llu, using FILE as fallback\n",
2597                        rec->ino);
2598                 type = BTRFS_FT_REG_FILE;
2599                 type_recovered = 1;
2600         }
2601
2602         ret = reset_nlink(trans, root, path, rec);
2603         if (ret < 0) {
2604                 fprintf(stderr,
2605                         "Failed to reset nlink for inode %llu: %s\n",
2606                         rec->ino, strerror(-ret));
2607                 goto out;
2608         }
2609
2610         if (rec->found_link == 0) {
2611                 lost_found_ino = root->highest_inode;
2612                 if (lost_found_ino >= BTRFS_LAST_FREE_OBJECTID) {
2613                         ret = -EOVERFLOW;
2614                         goto out;
2615                 }
2616                 lost_found_ino++;
2617                 ret = btrfs_mkdir(trans, root, dir_name, strlen(dir_name),
2618                                   BTRFS_FIRST_FREE_OBJECTID, &lost_found_ino,
2619                                   mode);
2620                 if (ret < 0) {
2621                         fprintf(stderr, "Failed to create '%s' dir: %s\n",
2622                                 dir_name, strerror(-ret));
2623                         goto out;
2624                 }
2625                 ret = btrfs_add_link(trans, root, rec->ino, lost_found_ino,
2626                                      namebuf, namelen, type, NULL, 1);
2627                 /*
2628                  * Add ".INO" suffix several times to handle case where
2629                  * "FILENAME.INO" is already taken by another file.
2630                  */
2631                 while (ret == -EEXIST) {
2632                         /*
2633                          * Conflicting file name, add ".INO" as suffix * +1 for '.'
2634                          */
2635                         if (namelen + count_digits(rec->ino) + 1 >
2636                             BTRFS_NAME_LEN) {
2637                                 ret = -EFBIG;
2638                                 goto out;
2639                         }
2640                         snprintf(namebuf + namelen, BTRFS_NAME_LEN - namelen,
2641                                  ".%llu", rec->ino);
2642                         namelen += count_digits(rec->ino) + 1;
2643                         ret = btrfs_add_link(trans, root, rec->ino,
2644                                              lost_found_ino, namebuf,
2645                                              namelen, type, NULL, 1);
2646                 }
2647                 if (ret < 0) {
2648                         fprintf(stderr,
2649                                 "Failed to link the inode %llu to %s dir: %s\n",
2650                                 rec->ino, dir_name, strerror(-ret));
2651                         goto out;
2652                 }
2653                 /*
2654                  * Just increase the found_link, don't actually add the
2655                  * backref. This will make things easier and this inode
2656                  * record will be freed after the repair is done.
2657                  * So fsck will not report problem about this inode.
2658                  */
2659                 rec->found_link++;
2660                 printf("Moving file '%.*s' to '%s' dir since it has no valid backref\n",
2661                        namelen, namebuf, dir_name);
2662         }
2663         printf("Fixed the nlink of inode %llu\n", rec->ino);
2664 out:
2665         /*
2666          * Clear the flag anyway, or we will loop forever for the same inode
2667          * as it will not be removed from the bad inode list and the dead loop
2668          * happens.
2669          */
2670         rec->errors &= ~I_ERR_LINK_COUNT_WRONG;
2671         btrfs_release_path(path);
2672         return ret;
2673 }
2674
2675 /*
2676  * Check if there is any normal(reg or prealloc) file extent for given
2677  * ino.
2678  * This is used to determine the file type when neither its dir_index/item or
2679  * inode_item exists.
2680  *
2681  * This will *NOT* report error, if any error happens, just consider it does
2682  * not have any normal file extent.
2683  */
2684 static int find_normal_file_extent(struct btrfs_root *root, u64 ino)
2685 {
2686         struct btrfs_path path;
2687         struct btrfs_key key;
2688         struct btrfs_key found_key;
2689         struct btrfs_file_extent_item *fi;
2690         u8 type;
2691         int ret = 0;
2692
2693         btrfs_init_path(&path);
2694         key.objectid = ino;
2695         key.type = BTRFS_EXTENT_DATA_KEY;
2696         key.offset = 0;
2697
2698         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
2699         if (ret < 0) {
2700                 ret = 0;
2701                 goto out;
2702         }
2703         if (ret && path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
2704                 ret = btrfs_next_leaf(root, &path);
2705                 if (ret) {
2706                         ret = 0;
2707                         goto out;
2708                 }
2709         }
2710         while (1) {
2711                 btrfs_item_key_to_cpu(path.nodes[0], &found_key,
2712                                       path.slots[0]);
2713                 if (found_key.objectid != ino ||
2714                     found_key.type != BTRFS_EXTENT_DATA_KEY)
2715                         break;
2716                 fi = btrfs_item_ptr(path.nodes[0], path.slots[0],
2717                                     struct btrfs_file_extent_item);
2718                 type = btrfs_file_extent_type(path.nodes[0], fi);
2719                 if (type != BTRFS_FILE_EXTENT_INLINE) {
2720                         ret = 1;
2721                         goto out;
2722                 }
2723         }
2724 out:
2725         btrfs_release_path(&path);
2726         return ret;
2727 }
2728
2729 static u32 btrfs_type_to_imode(u8 type)
2730 {
2731         static u32 imode_by_btrfs_type[] = {
2732                 [BTRFS_FT_REG_FILE]     = S_IFREG,
2733                 [BTRFS_FT_DIR]          = S_IFDIR,
2734                 [BTRFS_FT_CHRDEV]       = S_IFCHR,
2735                 [BTRFS_FT_BLKDEV]       = S_IFBLK,
2736                 [BTRFS_FT_FIFO]         = S_IFIFO,
2737                 [BTRFS_FT_SOCK]         = S_IFSOCK,
2738                 [BTRFS_FT_SYMLINK]      = S_IFLNK,
2739         };
2740
2741         return imode_by_btrfs_type[(type)];
2742 }
2743
2744 static int repair_inode_no_item(struct btrfs_trans_handle *trans,
2745                                 struct btrfs_root *root,
2746                                 struct btrfs_path *path,
2747                                 struct inode_record *rec)
2748 {
2749         u8 filetype;
2750         u32 mode = 0700;
2751         int type_recovered = 0;
2752         int ret = 0;
2753
2754         printf("Trying to rebuild inode:%llu\n", rec->ino);
2755
2756         type_recovered = !find_file_type(rec, &filetype);
2757
2758         /*
2759          * Try to determine inode type if type not found.
2760          *
2761          * For found regular file extent, it must be FILE.
2762          * For found dir_item/index, it must be DIR.
2763          *
2764          * For undetermined one, use FILE as fallback.
2765          *
2766          * TODO:
2767          * 1. If found backref(inode_index/item is already handled) to it,
2768          *    it must be DIR.
2769          *    Need new inode-inode ref structure to allow search for that.
2770          */
2771         if (!type_recovered) {
2772                 if (rec->found_file_extent &&
2773                     find_normal_file_extent(root, rec->ino)) {
2774                         type_recovered = 1;
2775                         filetype = BTRFS_FT_REG_FILE;
2776                 } else if (rec->found_dir_item) {
2777                         type_recovered = 1;
2778                         filetype = BTRFS_FT_DIR;
2779                 } else if (!list_empty(&rec->orphan_extents)) {
2780                         type_recovered = 1;
2781                         filetype = BTRFS_FT_REG_FILE;
2782                 } else{
2783                         printf("Can't determine the filetype for inode %llu, assume it is a normal file\n",
2784                                rec->ino);
2785                         type_recovered = 1;
2786                         filetype = BTRFS_FT_REG_FILE;
2787                 }
2788         }
2789
2790         ret = btrfs_new_inode(trans, root, rec->ino,
2791                               mode | btrfs_type_to_imode(filetype));
2792         if (ret < 0)
2793                 goto out;
2794
2795         /*
2796          * Here inode rebuild is done, we only rebuild the inode item,
2797          * don't repair the nlink(like move to lost+found).
2798          * That is the job of nlink repair.
2799          *
2800          * We just fill the record and return
2801          */
2802         rec->found_dir_item = 1;
2803         rec->imode = mode | btrfs_type_to_imode(filetype);
2804         rec->nlink = 0;
2805         rec->errors &= ~I_ERR_NO_INODE_ITEM;
2806         /* Ensure the inode_nlinks repair function will be called */
2807         rec->errors |= I_ERR_LINK_COUNT_WRONG;
2808 out:
2809         return ret;
2810 }
2811
2812 static int repair_inode_orphan_extent(struct btrfs_trans_handle *trans,
2813                                       struct btrfs_root *root,
2814                                       struct btrfs_path *path,
2815                                       struct inode_record *rec)
2816 {
2817         struct orphan_data_extent *orphan;
2818         struct orphan_data_extent *tmp;
2819         int ret = 0;
2820
2821         list_for_each_entry_safe(orphan, tmp, &rec->orphan_extents, list) {
2822                 /*
2823                  * Check for conflicting file extents
2824                  *
2825                  * Here we don't know whether the extents is compressed or not,
2826                  * so we can only assume it not compressed nor data offset,
2827                  * and use its disk_len as extent length.
2828                  */
2829                 ret = btrfs_get_extent(NULL, root, path, orphan->objectid,
2830                                        orphan->offset, orphan->disk_len, 0);
2831                 btrfs_release_path(path);
2832                 if (ret < 0)
2833                         goto out;
2834                 if (!ret) {
2835                         fprintf(stderr,
2836                                 "orphan extent (%llu, %llu) conflicts, delete the orphan\n",
2837                                 orphan->disk_bytenr, orphan->disk_len);
2838                         ret = btrfs_free_extent(trans,
2839                                         root->fs_info->extent_root,
2840                                         orphan->disk_bytenr, orphan->disk_len,
2841                                         0, root->objectid, orphan->objectid,
2842                                         orphan->offset);
2843                         if (ret < 0)
2844                                 goto out;
2845                 }
2846                 ret = btrfs_insert_file_extent(trans, root, orphan->objectid,
2847                                 orphan->offset, orphan->disk_bytenr,
2848                                 orphan->disk_len, orphan->disk_len);
2849                 if (ret < 0)
2850                         goto out;
2851
2852                 /* Update file size info */
2853                 rec->found_size += orphan->disk_len;
2854                 if (rec->found_size == rec->nbytes)
2855                         rec->errors &= ~I_ERR_FILE_NBYTES_WRONG;
2856
2857                 /* Update the file extent hole info too */
2858                 ret = del_file_extent_hole(&rec->holes, orphan->offset,
2859                                            orphan->disk_len);
2860                 if (ret < 0)
2861                         goto out;
2862                 if (RB_EMPTY_ROOT(&rec->holes))
2863                         rec->errors &= ~I_ERR_FILE_EXTENT_DISCOUNT;
2864
2865                 list_del(&orphan->list);
2866                 free(orphan);
2867         }
2868         rec->errors &= ~I_ERR_FILE_EXTENT_ORPHAN;
2869 out:
2870         return ret;
2871 }
2872
2873 static int repair_inode_discount_extent(struct btrfs_trans_handle *trans,
2874                                         struct btrfs_root *root,
2875                                         struct btrfs_path *path,
2876                                         struct inode_record *rec)
2877 {
2878         struct rb_node *node;
2879         struct file_extent_hole *hole;
2880         int found = 0;
2881         int ret = 0;
2882
2883         node = rb_first(&rec->holes);
2884
2885         while (node) {
2886                 found = 1;
2887                 hole = rb_entry(node, struct file_extent_hole, node);
2888                 ret = btrfs_punch_hole(trans, root, rec->ino,
2889                                        hole->start, hole->len);
2890                 if (ret < 0)
2891                         goto out;
2892                 ret = del_file_extent_hole(&rec->holes, hole->start,
2893                                            hole->len);
2894                 if (ret < 0)
2895                         goto out;
2896                 if (RB_EMPTY_ROOT(&rec->holes))
2897                         rec->errors &= ~I_ERR_FILE_EXTENT_DISCOUNT;
2898                 node = rb_first(&rec->holes);
2899         }
2900         /* special case for a file losing all its file extent */
2901         if (!found) {
2902                 ret = btrfs_punch_hole(trans, root, rec->ino, 0,
2903                                        round_up(rec->isize, root->sectorsize));
2904                 if (ret < 0)
2905                         goto out;
2906         }
2907         printf("Fixed discount file extents for inode: %llu in root: %llu\n",
2908                rec->ino, root->objectid);
2909 out:
2910         return ret;
2911 }
2912
2913 static int try_repair_inode(struct btrfs_root *root, struct inode_record *rec)
2914 {
2915         struct btrfs_trans_handle *trans;
2916         struct btrfs_path path;
2917         int ret = 0;
2918
2919         if (!(rec->errors & (I_ERR_DIR_ISIZE_WRONG |
2920                              I_ERR_NO_ORPHAN_ITEM |
2921                              I_ERR_LINK_COUNT_WRONG |
2922                              I_ERR_NO_INODE_ITEM |
2923                              I_ERR_FILE_EXTENT_ORPHAN |
2924                              I_ERR_FILE_EXTENT_DISCOUNT|
2925                              I_ERR_FILE_NBYTES_WRONG)))
2926                 return rec->errors;
2927
2928         /*
2929          * For nlink repair, it may create a dir and add link, so
2930          * 2 for parent(256)'s dir_index and dir_item
2931          * 2 for lost+found dir's inode_item and inode_ref
2932          * 1 for the new inode_ref of the file
2933          * 2 for lost+found dir's dir_index and dir_item for the file
2934          */
2935         trans = btrfs_start_transaction(root, 7);
2936         if (IS_ERR(trans))
2937                 return PTR_ERR(trans);
2938
2939         btrfs_init_path(&path);
2940         if (rec->errors & I_ERR_NO_INODE_ITEM)
2941                 ret = repair_inode_no_item(trans, root, &path, rec);
2942         if (!ret && rec->errors & I_ERR_FILE_EXTENT_ORPHAN)
2943                 ret = repair_inode_orphan_extent(trans, root, &path, rec);
2944         if (!ret && rec->errors & I_ERR_FILE_EXTENT_DISCOUNT)
2945                 ret = repair_inode_discount_extent(trans, root, &path, rec);
2946         if (!ret && rec->errors & I_ERR_DIR_ISIZE_WRONG)
2947                 ret = repair_inode_isize(trans, root, &path, rec);
2948         if (!ret && rec->errors & I_ERR_NO_ORPHAN_ITEM)
2949                 ret = repair_inode_orphan_item(trans, root, &path, rec);
2950         if (!ret && rec->errors & I_ERR_LINK_COUNT_WRONG)
2951                 ret = repair_inode_nlinks(trans, root, &path, rec);
2952         if (!ret && rec->errors & I_ERR_FILE_NBYTES_WRONG)
2953                 ret = repair_inode_nbytes(trans, root, &path, rec);
2954         btrfs_commit_transaction(trans, root);
2955         btrfs_release_path(&path);
2956         return ret;
2957 }
2958
2959 static int check_inode_recs(struct btrfs_root *root,
2960                             struct cache_tree *inode_cache)
2961 {
2962         struct cache_extent *cache;
2963         struct ptr_node *node;
2964         struct inode_record *rec;
2965         struct inode_backref *backref;
2966         int stage = 0;
2967         int ret = 0;
2968         int err = 0;
2969         u64 error = 0;
2970         u64 root_dirid = btrfs_root_dirid(&root->root_item);
2971
2972         if (btrfs_root_refs(&root->root_item) == 0) {
2973                 if (!cache_tree_empty(inode_cache))
2974                         fprintf(stderr, "warning line %d\n", __LINE__);
2975                 return 0;
2976         }
2977
2978         /*
2979          * We need to record the highest inode number for later 'lost+found'
2980          * dir creation.
2981          * We must select an ino not used/referred by any existing inode, or
2982          * 'lost+found' ino may be a missing ino in a corrupted leaf,
2983          * this may cause 'lost+found' dir has wrong nlinks.
2984          */
2985         cache = last_cache_extent(inode_cache);
2986         if (cache) {
2987                 node = container_of(cache, struct ptr_node, cache);
2988                 rec = node->data;
2989                 if (rec->ino > root->highest_inode)
2990                         root->highest_inode = rec->ino;
2991         }
2992
2993         /*
2994          * We need to repair backrefs first because we could change some of the
2995          * errors in the inode recs.
2996          *
2997          * We also need to go through and delete invalid backrefs first and then
2998          * add the correct ones second.  We do this because we may get EEXIST
2999          * when adding back the correct index because we hadn't yet deleted the
3000          * invalid index.
3001          *
3002          * For example, if we were missing a dir index then the directories
3003          * isize would be wrong, so if we fixed the isize to what we thought it
3004          * would be and then fixed the backref we'd still have a invalid fs, so
3005          * we need to add back the dir index and then check to see if the isize
3006          * is still wrong.
3007          */
3008         while (stage < 3) {
3009                 stage++;
3010                 if (stage == 3 && !err)
3011                         break;
3012
3013                 cache = search_cache_extent(inode_cache, 0);
3014                 while (repair && cache) {
3015                         node = container_of(cache, struct ptr_node, cache);
3016                         rec = node->data;
3017                         cache = next_cache_extent(cache);
3018
3019                         /* Need to free everything up and rescan */
3020                         if (stage == 3) {
3021                                 remove_cache_extent(inode_cache, &node->cache);
3022                                 free(node);
3023                                 free_inode_rec(rec);
3024                                 continue;
3025                         }
3026
3027                         if (list_empty(&rec->backrefs))
3028                                 continue;
3029
3030                         ret = repair_inode_backrefs(root, rec, inode_cache,
3031                                                     stage == 1);
3032                         if (ret < 0) {
3033                                 err = ret;
3034                                 stage = 2;
3035                                 break;
3036                         } if (ret > 0) {
3037                                 err = -EAGAIN;
3038                         }
3039                 }
3040         }
3041         if (err)
3042                 return err;
3043
3044         rec = get_inode_rec(inode_cache, root_dirid, 0);
3045         BUG_ON(IS_ERR(rec));
3046         if (rec) {
3047                 ret = check_root_dir(rec);
3048                 if (ret) {
3049                         fprintf(stderr, "root %llu root dir %llu error\n",
3050                                 (unsigned long long)root->root_key.objectid,
3051                                 (unsigned long long)root_dirid);
3052                         print_inode_error(root, rec);
3053                         error++;
3054                 }
3055         } else {
3056                 if (repair) {
3057                         struct btrfs_trans_handle *trans;
3058
3059                         trans = btrfs_start_transaction(root, 1);
3060                         if (IS_ERR(trans)) {
3061                                 err = PTR_ERR(trans);
3062                                 return err;
3063                         }
3064
3065                         fprintf(stderr,
3066                                 "root %llu missing its root dir, recreating\n",
3067                                 (unsigned long long)root->objectid);
3068
3069                         ret = btrfs_make_root_dir(trans, root, root_dirid);
3070                         BUG_ON(ret);
3071
3072                         btrfs_commit_transaction(trans, root);
3073                         return -EAGAIN;
3074                 }
3075
3076                 fprintf(stderr, "root %llu root dir %llu not found\n",
3077                         (unsigned long long)root->root_key.objectid,
3078                         (unsigned long long)root_dirid);
3079         }
3080
3081         while (1) {
3082                 cache = search_cache_extent(inode_cache, 0);
3083                 if (!cache)
3084                         break;
3085                 node = container_of(cache, struct ptr_node, cache);
3086                 rec = node->data;
3087                 remove_cache_extent(inode_cache, &node->cache);
3088                 free(node);
3089                 if (rec->ino == root_dirid ||
3090                     rec->ino == BTRFS_ORPHAN_OBJECTID) {
3091                         free_inode_rec(rec);
3092                         continue;
3093                 }
3094
3095                 if (rec->errors & I_ERR_NO_ORPHAN_ITEM) {
3096                         ret = check_orphan_item(root, rec->ino);
3097                         if (ret == 0)
3098                                 rec->errors &= ~I_ERR_NO_ORPHAN_ITEM;
3099                         if (can_free_inode_rec(rec)) {
3100                                 free_inode_rec(rec);
3101                                 continue;
3102                         }
3103                 }
3104
3105                 if (!rec->found_inode_item)
3106                         rec->errors |= I_ERR_NO_INODE_ITEM;
3107                 if (rec->found_link != rec->nlink)
3108                         rec->errors |= I_ERR_LINK_COUNT_WRONG;
3109                 if (repair) {
3110                         ret = try_repair_inode(root, rec);
3111                         if (ret == 0 && can_free_inode_rec(rec)) {
3112                                 free_inode_rec(rec);
3113                                 continue;
3114                         }
3115                         ret = 0;
3116                 }
3117
3118                 if (!(repair && ret == 0))
3119                         error++;
3120                 print_inode_error(root, rec);
3121                 list_for_each_entry(backref, &rec->backrefs, list) {
3122                         if (!backref->found_dir_item)
3123                                 backref->errors |= REF_ERR_NO_DIR_ITEM;
3124                         if (!backref->found_dir_index)
3125                                 backref->errors |= REF_ERR_NO_DIR_INDEX;
3126                         if (!backref->found_inode_ref)
3127                                 backref->errors |= REF_ERR_NO_INODE_REF;
3128                         fprintf(stderr, "\tunresolved ref dir %llu index %llu"
3129                                 " namelen %u name %s filetype %d errors %x",
3130                                 (unsigned long long)backref->dir,
3131                                 (unsigned long long)backref->index,
3132                                 backref->namelen, backref->name,
3133                                 backref->filetype, backref->errors);
3134                         print_ref_error(backref->errors);
3135                 }
3136                 free_inode_rec(rec);
3137         }
3138         return (error > 0) ? -1 : 0;
3139 }
3140
3141 static struct root_record *get_root_rec(struct cache_tree *root_cache,
3142                                         u64 objectid)
3143 {
3144         struct cache_extent *cache;
3145         struct root_record *rec = NULL;
3146         int ret;
3147
3148         cache = lookup_cache_extent(root_cache, objectid, 1);
3149         if (cache) {
3150                 rec = container_of(cache, struct root_record, cache);
3151         } else {
3152                 rec = calloc(1, sizeof(*rec));
3153                 if (!rec)
3154                         return ERR_PTR(-ENOMEM);
3155                 rec->objectid = objectid;
3156                 INIT_LIST_HEAD(&rec->backrefs);
3157                 rec->cache.start = objectid;
3158                 rec->cache.size = 1;
3159
3160                 ret = insert_cache_extent(root_cache, &rec->cache);
3161                 if (ret)
3162                         return ERR_PTR(-EEXIST);
3163         }
3164         return rec;
3165 }
3166
3167 static struct root_backref *get_root_backref(struct root_record *rec,
3168                                              u64 ref_root, u64 dir, u64 index,
3169                                              const char *name, int namelen)
3170 {
3171         struct root_backref *backref;
3172
3173         list_for_each_entry(backref, &rec->backrefs, list) {
3174                 if (backref->ref_root != ref_root || backref->dir != dir ||
3175                     backref->namelen != namelen)
3176                         continue;
3177                 if (memcmp(name, backref->name, namelen))
3178                         continue;
3179                 return backref;
3180         }
3181
3182         backref = calloc(1, sizeof(*backref) + namelen + 1);
3183         if (!backref)
3184                 return NULL;
3185         backref->ref_root = ref_root;
3186         backref->dir = dir;
3187         backref->index = index;
3188         backref->namelen = namelen;
3189         memcpy(backref->name, name, namelen);
3190         backref->name[namelen] = '\0';
3191         list_add_tail(&backref->list, &rec->backrefs);
3192         return backref;
3193 }
3194
3195 static void free_root_record(struct cache_extent *cache)
3196 {
3197         struct root_record *rec;
3198         struct root_backref *backref;
3199
3200         rec = container_of(cache, struct root_record, cache);
3201         while (!list_empty(&rec->backrefs)) {
3202                 backref = to_root_backref(rec->backrefs.next);
3203                 list_del(&backref->list);
3204                 free(backref);
3205         }
3206
3207         free(rec);
3208 }
3209
3210 FREE_EXTENT_CACHE_BASED_TREE(root_recs, free_root_record);
3211
3212 static int add_root_backref(struct cache_tree *root_cache,
3213                             u64 root_id, u64 ref_root, u64 dir, u64 index,
3214                             const char *name, int namelen,
3215                             int item_type, int errors)
3216 {
3217         struct root_record *rec;
3218         struct root_backref *backref;
3219
3220         rec = get_root_rec(root_cache, root_id);
3221         BUG_ON(IS_ERR(rec));
3222         backref = get_root_backref(rec, ref_root, dir, index, name, namelen);
3223         BUG_ON(!backref);
3224
3225         backref->errors |= errors;
3226
3227         if (item_type != BTRFS_DIR_ITEM_KEY) {
3228                 if (backref->found_dir_index || backref->found_back_ref ||
3229                     backref->found_forward_ref) {
3230                         if (backref->index != index)
3231                                 backref->errors |= REF_ERR_INDEX_UNMATCH;
3232                 } else {
3233                         backref->index = index;
3234                 }
3235         }
3236
3237         if (item_type == BTRFS_DIR_ITEM_KEY) {
3238                 if (backref->found_forward_ref)
3239                         rec->found_ref++;
3240                 backref->found_dir_item = 1;
3241         } else if (item_type == BTRFS_DIR_INDEX_KEY) {
3242                 backref->found_dir_index = 1;
3243         } else if (item_type == BTRFS_ROOT_REF_KEY) {
3244                 if (backref->found_forward_ref)
3245                         backref->errors |= REF_ERR_DUP_ROOT_REF;
3246                 else if (backref->found_dir_item)
3247                         rec->found_ref++;
3248                 backref->found_forward_ref = 1;
3249         } else if (item_type == BTRFS_ROOT_BACKREF_KEY) {
3250                 if (backref->found_back_ref)
3251                         backref->errors |= REF_ERR_DUP_ROOT_BACKREF;
3252                 backref->found_back_ref = 1;
3253         } else {
3254                 BUG_ON(1);
3255         }
3256
3257         if (backref->found_forward_ref && backref->found_dir_item)
3258                 backref->reachable = 1;
3259         return 0;
3260 }
3261
3262 static int merge_root_recs(struct btrfs_root *root,
3263                            struct cache_tree *src_cache,
3264                            struct cache_tree *dst_cache)
3265 {
3266         struct cache_extent *cache;
3267         struct ptr_node *node;
3268         struct inode_record *rec;
3269         struct inode_backref *backref;
3270         int ret = 0;
3271
3272         if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
3273                 free_inode_recs_tree(src_cache);
3274                 return 0;
3275         }
3276
3277         while (1) {
3278                 cache = search_cache_extent(src_cache, 0);
3279                 if (!cache)
3280                         break;
3281                 node = container_of(cache, struct ptr_node, cache);
3282                 rec = node->data;
3283                 remove_cache_extent(src_cache, &node->cache);
3284                 free(node);
3285
3286                 ret = is_child_root(root, root->objectid, rec->ino);
3287                 if (ret < 0)
3288                         break;
3289                 else if (ret == 0)
3290                         goto skip;
3291
3292                 list_for_each_entry(backref, &rec->backrefs, list) {
3293                         BUG_ON(backref->found_inode_ref);
3294                         if (backref->found_dir_item)
3295                                 add_root_backref(dst_cache, rec->ino,
3296                                         root->root_key.objectid, backref->dir,
3297                                         backref->index, backref->name,
3298                                         backref->namelen, BTRFS_DIR_ITEM_KEY,
3299                                         backref->errors);
3300                         if (backref->found_dir_index)
3301                                 add_root_backref(dst_cache, rec->ino,
3302                                         root->root_key.objectid, backref->dir,
3303                                         backref->index, backref->name,
3304                                         backref->namelen, BTRFS_DIR_INDEX_KEY,
3305                                         backref->errors);
3306                 }
3307 skip:
3308                 free_inode_rec(rec);
3309         }
3310         if (ret < 0)
3311                 return ret;
3312         return 0;
3313 }
3314
3315 static int check_root_refs(struct btrfs_root *root,
3316                            struct cache_tree *root_cache)
3317 {
3318         struct root_record *rec;
3319         struct root_record *ref_root;
3320         struct root_backref *backref;
3321         struct cache_extent *cache;
3322         int loop = 1;
3323         int ret;
3324         int error;
3325         int errors = 0;
3326
3327         rec = get_root_rec(root_cache, BTRFS_FS_TREE_OBJECTID);
3328         BUG_ON(IS_ERR(rec));
3329         rec->found_ref = 1;
3330
3331         /* fixme: this can not detect circular references */
3332         while (loop) {
3333                 loop = 0;
3334                 cache = search_cache_extent(root_cache, 0);
3335                 while (1) {
3336                         if (!cache)
3337                                 break;
3338                         rec = container_of(cache, struct root_record, cache);
3339                         cache = next_cache_extent(cache);
3340
3341                         if (rec->found_ref == 0)
3342                                 continue;
3343
3344                         list_for_each_entry(backref, &rec->backrefs, list) {
3345                                 if (!backref->reachable)
3346                                         continue;
3347
3348                                 ref_root = get_root_rec(root_cache,
3349                                                         backref->ref_root);
3350                                 BUG_ON(IS_ERR(ref_root));
3351                                 if (ref_root->found_ref > 0)
3352                                         continue;
3353
3354                                 backref->reachable = 0;
3355                                 rec->found_ref--;
3356                                 if (rec->found_ref == 0)
3357                                         loop = 1;
3358                         }
3359                 }
3360         }
3361
3362         cache = search_cache_extent(root_cache, 0);
3363         while (1) {
3364                 if (!cache)
3365                         break;
3366                 rec = container_of(cache, struct root_record, cache);
3367                 cache = next_cache_extent(cache);
3368
3369                 if (rec->found_ref == 0 &&
3370                     rec->objectid >= BTRFS_FIRST_FREE_OBJECTID &&
3371                     rec->objectid <= BTRFS_LAST_FREE_OBJECTID) {
3372                         ret = check_orphan_item(root->fs_info->tree_root,
3373                                                 rec->objectid);
3374                         if (ret == 0)
3375                                 continue;
3376
3377                         /*
3378                          * If we don't have a root item then we likely just have
3379                          * a dir item in a snapshot for this root but no actual
3380                          * ref key or anything so it's meaningless.
3381                          */
3382                         if (!rec->found_root_item)
3383                                 continue;
3384                         errors++;
3385                         fprintf(stderr, "fs tree %llu not referenced\n",
3386                                 (unsigned long long)rec->objectid);
3387                 }
3388
3389                 error = 0;
3390                 if (rec->found_ref > 0 && !rec->found_root_item)
3391                         error = 1;
3392                 list_for_each_entry(backref, &rec->backrefs, list) {
3393                         if (!backref->found_dir_item)
3394                                 backref->errors |= REF_ERR_NO_DIR_ITEM;
3395                         if (!backref->found_dir_index)
3396                                 backref->errors |= REF_ERR_NO_DIR_INDEX;
3397                         if (!backref->found_back_ref)
3398                                 backref->errors |= REF_ERR_NO_ROOT_BACKREF;
3399                         if (!backref->found_forward_ref)
3400                                 backref->errors |= REF_ERR_NO_ROOT_REF;
3401                         if (backref->reachable && backref->errors)
3402                                 error = 1;
3403                 }
3404                 if (!error)
3405                         continue;
3406
3407                 errors++;
3408                 fprintf(stderr, "fs tree %llu refs %u %s\n",
3409                         (unsigned long long)rec->objectid, rec->found_ref,
3410                          rec->found_root_item ? "" : "not found");
3411
3412                 list_for_each_entry(backref, &rec->backrefs, list) {
3413                         if (!backref->reachable)
3414                                 continue;
3415                         if (!backref->errors && rec->found_root_item)
3416                                 continue;
3417                         fprintf(stderr, "\tunresolved ref root %llu dir %llu"
3418                                 " index %llu namelen %u name %s errors %x\n",
3419                                 (unsigned long long)backref->ref_root,
3420                                 (unsigned long long)backref->dir,
3421                                 (unsigned long long)backref->index,
3422                                 backref->namelen, backref->name,
3423                                 backref->errors);
3424                         print_ref_error(backref->errors);
3425                 }
3426         }
3427         return errors > 0 ? 1 : 0;
3428 }
3429
3430 static int process_root_ref(struct extent_buffer *eb, int slot,
3431                             struct btrfs_key *key,
3432                             struct cache_tree *root_cache)
3433 {
3434         u64 dirid;
3435         u64 index;
3436         u32 len;
3437         u32 name_len;
3438         struct btrfs_root_ref *ref;
3439         char namebuf[BTRFS_NAME_LEN];
3440         int error;
3441
3442         ref = btrfs_item_ptr(eb, slot, struct btrfs_root_ref);
3443
3444         dirid = btrfs_root_ref_dirid(eb, ref);
3445         index = btrfs_root_ref_sequence(eb, ref);
3446         name_len = btrfs_root_ref_name_len(eb, ref);
3447
3448         if (name_len <= BTRFS_NAME_LEN) {
3449                 len = name_len;
3450                 error = 0;
3451         } else {
3452                 len = BTRFS_NAME_LEN;
3453                 error = REF_ERR_NAME_TOO_LONG;
3454         }
3455         read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
3456
3457         if (key->type == BTRFS_ROOT_REF_KEY) {
3458                 add_root_backref(root_cache, key->offset, key->objectid, dirid,
3459                                  index, namebuf, len, key->type, error);
3460         } else {
3461                 add_root_backref(root_cache, key->objectid, key->offset, dirid,
3462                                  index, namebuf, len, key->type, error);
3463         }
3464         return 0;
3465 }
3466
3467 static void free_corrupt_block(struct cache_extent *cache)
3468 {
3469         struct btrfs_corrupt_block *corrupt;
3470
3471         corrupt = container_of(cache, struct btrfs_corrupt_block, cache);
3472         free(corrupt);
3473 }
3474
3475 FREE_EXTENT_CACHE_BASED_TREE(corrupt_blocks, free_corrupt_block);
3476
3477 /*
3478  * Repair the btree of the given root.
3479  *
3480  * The fix is to remove the node key in corrupt_blocks cache_tree.
3481  * and rebalance the tree.
3482  * After the fix, the btree should be writeable.
3483  */
3484 static int repair_btree(struct btrfs_root *root,
3485                         struct cache_tree *corrupt_blocks)
3486 {
3487         struct btrfs_trans_handle *trans;
3488         struct btrfs_path path;
3489         struct btrfs_corrupt_block *corrupt;
3490         struct cache_extent *cache;
3491         struct btrfs_key key;
3492         u64 offset;
3493         int level;
3494         int ret = 0;
3495
3496         if (cache_tree_empty(corrupt_blocks))
3497                 return 0;
3498
3499         trans = btrfs_start_transaction(root, 1);
3500         if (IS_ERR(trans)) {
3501                 ret = PTR_ERR(trans);
3502                 fprintf(stderr, "Error starting transaction: %s\n",
3503                         strerror(-ret));
3504                 return ret;
3505         }
3506         btrfs_init_path(&path);
3507         cache = first_cache_extent(corrupt_blocks);
3508         while (cache) {
3509                 corrupt = container_of(cache, struct btrfs_corrupt_block,
3510                                        cache);
3511                 level = corrupt->level;
3512                 path.lowest_level = level;
3513                 key.objectid = corrupt->key.objectid;
3514                 key.type = corrupt->key.type;
3515                 key.offset = corrupt->key.offset;
3516
3517                 /*
3518                  * Here we don't want to do any tree balance, since it may
3519                  * cause a balance with corrupted brother leaf/node,
3520                  * so ins_len set to 0 here.
3521                  * Balance will be done after all corrupt node/leaf is deleted.
3522                  */
3523                 ret = btrfs_search_slot(trans, root, &key, &path, 0, 1);
3524                 if (ret < 0)
3525                         goto out;
3526                 offset = btrfs_node_blockptr(path.nodes[level],
3527                                              path.slots[level]);
3528
3529                 /* Remove the ptr */
3530                 ret = btrfs_del_ptr(trans, root, &path, level,
3531                                     path.slots[level]);
3532                 if (ret < 0)
3533                         goto out;
3534                 /*
3535                  * Remove the corresponding extent
3536                  * return value is not concerned.
3537                  */
3538                 btrfs_release_path(&path);
3539                 ret = btrfs_free_extent(trans, root, offset, root->nodesize,
3540                                         0, root->root_key.objectid,
3541                                         level - 1, 0);
3542                 cache = next_cache_extent(cache);
3543         }
3544
3545         /* Balance the btree using btrfs_search_slot() */
3546         cache = first_cache_extent(corrupt_blocks);
3547         while (cache) {
3548                 corrupt = container_of(cache, struct btrfs_corrupt_block,
3549                                        cache);
3550                 memcpy(&key, &corrupt->key, sizeof(key));
3551                 ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
3552                 if (ret < 0)
3553                         goto out;
3554                 /* return will always >0 since it won't find the item */
3555                 ret = 0;
3556                 btrfs_release_path(&path);
3557                 cache = next_cache_extent(cache);
3558         }
3559 out:
3560         btrfs_commit_transaction(trans, root);
3561         btrfs_release_path(&path);
3562         return ret;
3563 }
3564
3565 static int check_fs_root(struct btrfs_root *root,
3566                          struct cache_tree *root_cache,
3567                          struct walk_control *wc)
3568 {
3569         int ret = 0;
3570         int err = 0;
3571         int wret;
3572         int level;
3573         struct btrfs_path path;
3574         struct shared_node root_node;
3575         struct root_record *rec;
3576         struct btrfs_root_item *root_item = &root->root_item;
3577         struct cache_tree corrupt_blocks;
3578         struct orphan_data_extent *orphan;
3579         struct orphan_data_extent *tmp;
3580         enum btrfs_tree_block_status status;
3581         struct node_refs nrefs;
3582
3583         /*
3584          * Reuse the corrupt_block cache tree to record corrupted tree block
3585          *
3586          * Unlike the usage in extent tree check, here we do it in a per
3587          * fs/subvol tree base.
3588          */
3589         cache_tree_init(&corrupt_blocks);
3590         root->fs_info->corrupt_blocks = &corrupt_blocks;
3591
3592         if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
3593                 rec = get_root_rec(root_cache, root->root_key.objectid);
3594                 BUG_ON(IS_ERR(rec));
3595                 if (btrfs_root_refs(root_item) > 0)
3596                         rec->found_root_item = 1;
3597         }
3598
3599         btrfs_init_path(&path);
3600         memset(&root_node, 0, sizeof(root_node));
3601         cache_tree_init(&root_node.root_cache);
3602         cache_tree_init(&root_node.inode_cache);
3603         memset(&nrefs, 0, sizeof(nrefs));
3604
3605         /* Move the orphan extent record to corresponding inode_record */
3606         list_for_each_entry_safe(orphan, tmp,
3607                                  &root->orphan_data_extents, list) {
3608                 struct inode_record *inode;
3609
3610                 inode = get_inode_rec(&root_node.inode_cache, orphan->objectid,
3611                                       1);
3612                 BUG_ON(IS_ERR(inode));
3613                 inode->errors |= I_ERR_FILE_EXTENT_ORPHAN;
3614                 list_move(&orphan->list, &inode->orphan_extents);
3615         }
3616
3617         level = btrfs_header_level(root->node);
3618         memset(wc->nodes, 0, sizeof(wc->nodes));
3619         wc->nodes[level] = &root_node;
3620         wc->active_node = level;
3621         wc->root_level = level;
3622
3623         /* We may not have checked the root block, lets do that now */
3624         if (btrfs_is_leaf(root->node))
3625                 status = btrfs_check_leaf(root, NULL, root->node);
3626         else
3627                 status = btrfs_check_node(root, NULL, root->node);
3628         if (status != BTRFS_TREE_BLOCK_CLEAN)
3629                 return -EIO;
3630
3631         if (btrfs_root_refs(root_item) > 0 ||
3632             btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
3633                 path.nodes[level] = root->node;
3634                 extent_buffer_get(root->node);
3635                 path.slots[level] = 0;
3636         } else {
3637                 struct btrfs_key key;
3638                 struct btrfs_disk_key found_key;
3639
3640                 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
3641                 level = root_item->drop_level;
3642                 path.lowest_level = level;
3643                 if (level > btrfs_header_level(root->node) ||
3644                     level >= BTRFS_MAX_LEVEL) {
3645                         error("ignoring invalid drop level: %u", level);
3646                         goto skip_walking;
3647                 }
3648                 wret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
3649                 if (wret < 0)
3650                         goto skip_walking;
3651                 btrfs_node_key(path.nodes[level], &found_key,
3652                                 path.slots[level]);
3653                 WARN_ON(memcmp(&found_key, &root_item->drop_progress,
3654                                         sizeof(found_key)));
3655         }
3656
3657         while (1) {
3658                 wret = walk_down_tree(root, &path, wc, &level, &nrefs);
3659                 if (wret < 0)
3660                         ret = wret;
3661                 if (wret != 0)
3662                         break;
3663
3664                 wret = walk_up_tree(root, &path, wc, &level);
3665                 if (wret < 0)
3666                         ret = wret;
3667                 if (wret != 0)
3668                         break;
3669         }
3670 skip_walking:
3671         btrfs_release_path(&path);
3672
3673         if (!cache_tree_empty(&corrupt_blocks)) {
3674                 struct cache_extent *cache;
3675                 struct btrfs_corrupt_block *corrupt;
3676
3677                 printf("The following tree block(s) is corrupted in tree %llu:\n",
3678                        root->root_key.objectid);
3679                 cache = first_cache_extent(&corrupt_blocks);
3680                 while (cache) {
3681                         corrupt = container_of(cache,
3682                                                struct btrfs_corrupt_block,
3683                                                cache);
3684                         printf("\ttree block bytenr: %llu, level: %d, node key: (%llu, %u, %llu)\n",
3685                                cache->start, corrupt->level,
3686                                corrupt->key.objectid, corrupt->key.type,
3687                                corrupt->key.offset);
3688                         cache = next_cache_extent(cache);
3689                 }
3690                 if (repair) {
3691                         printf("Try to repair the btree for root %llu\n",
3692                                root->root_key.objectid);
3693                         ret = repair_btree(root, &corrupt_blocks);
3694                         if (ret < 0)
3695                                 fprintf(stderr, "Failed to repair btree: %s\n",
3696                                         strerror(-ret));
3697                         if (!ret)
3698                                 printf("Btree for root %llu is fixed\n",
3699                                        root->root_key.objectid);
3700                 }
3701         }
3702
3703         err = merge_root_recs(root, &root_node.root_cache, root_cache);
3704         if (err < 0)
3705                 ret = err;
3706
3707         if (root_node.current) {
3708                 root_node.current->checked = 1;
3709                 maybe_free_inode_rec(&root_node.inode_cache,
3710                                 root_node.current);
3711         }
3712
3713         err = check_inode_recs(root, &root_node.inode_cache);
3714         if (!ret)
3715                 ret = err;
3716
3717         free_corrupt_blocks_tree(&corrupt_blocks);
3718         root->fs_info->corrupt_blocks = NULL;
3719         free_orphan_data_extents(&root->orphan_data_extents);
3720         return ret;
3721 }
3722
3723 static int fs_root_objectid(u64 objectid)
3724 {
3725         if (objectid == BTRFS_TREE_RELOC_OBJECTID ||
3726             objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
3727                 return 1;
3728         return is_fstree(objectid);
3729 }
3730
3731 static int check_fs_roots(struct btrfs_root *root,
3732                           struct cache_tree *root_cache)
3733 {
3734         struct btrfs_path path;
3735         struct btrfs_key key;
3736         struct walk_control wc;
3737         struct extent_buffer *leaf, *tree_node;
3738         struct btrfs_root *tmp_root;
3739         struct btrfs_root *tree_root = root->fs_info->tree_root;
3740         int ret;
3741         int err = 0;
3742
3743         if (ctx.progress_enabled) {
3744                 ctx.tp = TASK_FS_ROOTS;
3745                 task_start(ctx.info);
3746         }
3747
3748         /*
3749          * Just in case we made any changes to the extent tree that weren't
3750          * reflected into the free space cache yet.
3751          */
3752         if (repair)
3753                 reset_cached_block_groups(root->fs_info);
3754         memset(&wc, 0, sizeof(wc));
3755         cache_tree_init(&wc.shared);
3756         btrfs_init_path(&path);
3757
3758 again:
3759         key.offset = 0;
3760         key.objectid = 0;
3761         key.type = BTRFS_ROOT_ITEM_KEY;
3762         ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
3763         if (ret < 0) {
3764                 err = 1;
3765                 goto out;
3766         }
3767         tree_node = tree_root->node;
3768         while (1) {
3769                 if (tree_node != tree_root->node) {
3770                         free_root_recs_tree(root_cache);
3771                         btrfs_release_path(&path);
3772                         goto again;
3773                 }
3774                 leaf = path.nodes[0];
3775                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
3776                         ret = btrfs_next_leaf(tree_root, &path);
3777                         if (ret) {
3778                                 if (ret < 0)
3779                                         err = 1;
3780                                 break;
3781                         }
3782                         leaf = path.nodes[0];
3783                 }
3784                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
3785                 if (key.type == BTRFS_ROOT_ITEM_KEY &&
3786                     fs_root_objectid(key.objectid)) {
3787                         if (key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
3788                                 tmp_root = btrfs_read_fs_root_no_cache(
3789                                                 root->fs_info, &key);
3790                         } else {
3791                                 key.offset = (u64)-1;
3792                                 tmp_root = btrfs_read_fs_root(
3793                                                 root->fs_info, &key);
3794                         }
3795                         if (IS_ERR(tmp_root)) {
3796                                 err = 1;
3797                                 goto next;
3798                         }
3799                         ret = check_fs_root(tmp_root, root_cache, &wc);
3800                         if (ret == -EAGAIN) {
3801                                 free_root_recs_tree(root_cache);
3802                                 btrfs_release_path(&path);
3803                                 goto again;
3804                         }
3805                         if (ret)
3806                                 err = 1;
3807                         if (key.objectid == BTRFS_TREE_RELOC_OBJECTID)
3808                                 btrfs_free_fs_root(tmp_root);
3809                 } else if (key.type == BTRFS_ROOT_REF_KEY ||
3810                            key.type == BTRFS_ROOT_BACKREF_KEY) {
3811                         process_root_ref(leaf, path.slots[0], &key,
3812                                          root_cache);
3813                 }
3814 next:
3815                 path.slots[0]++;
3816         }
3817 out:
3818         btrfs_release_path(&path);
3819         if (err)
3820                 free_extent_cache_tree(&wc.shared);
3821         if (!cache_tree_empty(&wc.shared))
3822                 fprintf(stderr, "warning line %d\n", __LINE__);
3823
3824         task_stop(ctx.info);
3825
3826         return err;
3827 }
3828
3829 static int all_backpointers_checked(struct extent_record *rec, int print_errs)
3830 {
3831         struct list_head *cur = rec->backrefs.next;
3832         struct extent_backref *back;
3833         struct tree_backref *tback;
3834         struct data_backref *dback;
3835         u64 found = 0;
3836         int err = 0;
3837
3838         while(cur != &rec->backrefs) {
3839                 back = to_extent_backref(cur);
3840                 cur = cur->next;
3841                 if (!back->found_extent_tree) {
3842                         err = 1;
3843                         if (!print_errs)
3844                                 goto out;
3845                         if (back->is_data) {
3846                                 dback = to_data_backref(back);
3847                                 fprintf(stderr, "Backref %llu %s %llu"
3848                                         " owner %llu offset %llu num_refs %lu"
3849                                         " not found in extent tree\n",
3850                                         (unsigned long long)rec->start,
3851                                         back->full_backref ?
3852                                         "parent" : "root",
3853                                         back->full_backref ?
3854                                         (unsigned long long)dback->parent:
3855                                         (unsigned long long)dback->root,
3856                                         (unsigned long long)dback->owner,
3857                                         (unsigned long long)dback->offset,
3858                                         (unsigned long)dback->num_refs);
3859                         } else {
3860                                 tback = to_tree_backref(back);
3861                                 fprintf(stderr, "Backref %llu parent %llu"
3862                                         " root %llu not found in extent tree\n",
3863                                         (unsigned long long)rec->start,
3864                                         (unsigned long long)tback->parent,
3865                                         (unsigned long long)tback->root);
3866                         }
3867                 }
3868                 if (!back->is_data && !back->found_ref) {
3869                         err = 1;
3870                         if (!print_errs)
3871                                 goto out;
3872                         tback = to_tree_backref(back);
3873                         fprintf(stderr, "Backref %llu %s %llu not referenced back %p\n",
3874                                 (unsigned long long)rec->start,
3875                                 back->full_backref ? "parent" : "root",
3876                                 back->full_backref ?
3877                                 (unsigned long long)tback->parent :
3878                                 (unsigned long long)tback->root, back);
3879                 }
3880                 if (back->is_data) {
3881                         dback = to_data_backref(back);
3882                         if (dback->found_ref != dback->num_refs) {
3883                                 err = 1;
3884                                 if (!print_errs)
3885                                         goto out;
3886                                 fprintf(stderr, "Incorrect local backref count"
3887                                         " on %llu %s %llu owner %llu"
3888                                         " offset %llu found %u wanted %u back %p\n",
3889                                         (unsigned long long)rec->start,
3890                                         back->full_backref ?
3891                                         "parent" : "root",
3892                                         back->full_backref ?
3893                                         (unsigned long long)dback->parent:
3894                                         (unsigned long long)dback->root,
3895                                         (unsigned long long)dback->owner,
3896                                         (unsigned long long)dback->offset,
3897                                         dback->found_ref, dback->num_refs, back);
3898                         }
3899                         if (dback->disk_bytenr != rec->start) {
3900                                 err = 1;
3901                                 if (!print_errs)
3902                                         goto out;
3903                                 fprintf(stderr, "Backref disk bytenr does not"
3904                                         " match extent record, bytenr=%llu, "
3905                                         "ref bytenr=%llu\n",
3906                                         (unsigned long long)rec->start,
3907                                         (unsigned long long)dback->disk_bytenr);
3908                         }
3909
3910                         if (dback->bytes != rec->nr) {
3911                                 err = 1;
3912                                 if (!print_errs)
3913                                         goto out;
3914                                 fprintf(stderr, "Backref bytes do not match "
3915                                         "extent backref, bytenr=%llu, ref "
3916                                         "bytes=%llu, backref bytes=%llu\n",
3917                                         (unsigned long long)rec->start,
3918                                         (unsigned long long)rec->nr,
3919                                         (unsigned long long)dback->bytes);
3920                         }
3921                 }
3922                 if (!back->is_data) {
3923                         found += 1;
3924                 } else {
3925                         dback = to_data_backref(back);
3926                         found += dback->found_ref;
3927                 }
3928         }
3929         if (found != rec->refs) {
3930                 err = 1;
3931                 if (!print_errs)
3932                         goto out;
3933                 fprintf(stderr, "Incorrect global backref count "
3934                         "on %llu found %llu wanted %llu\n",
3935                         (unsigned long long)rec->start,
3936                         (unsigned long long)found,
3937                         (unsigned long long)rec->refs);
3938         }
3939 out:
3940         return err;
3941 }
3942
3943 static int free_all_extent_backrefs(struct extent_record *rec)
3944 {
3945         struct extent_backref *back;
3946         struct list_head *cur;
3947         while (!list_empty(&rec->backrefs)) {
3948                 cur = rec->backrefs.next;
3949                 back = to_extent_backref(cur);
3950                 list_del(cur);
3951                 free(back);
3952         }
3953         return 0;
3954 }
3955
3956 static void free_extent_record_cache(struct btrfs_fs_info *fs_info,
3957                                      struct cache_tree *extent_cache)
3958 {
3959         struct cache_extent *cache;
3960         struct extent_record *rec;
3961
3962         while (1) {
3963                 cache = first_cache_extent(extent_cache);
3964                 if (!cache)
3965                         break;
3966                 rec = container_of(cache, struct extent_record, cache);
3967                 remove_cache_extent(extent_cache, cache);
3968                 free_all_extent_backrefs(rec);
3969                 free(rec);
3970         }
3971 }
3972
3973 static int maybe_free_extent_rec(struct cache_tree *extent_cache,
3974                                  struct extent_record *rec)
3975 {
3976         if (rec->content_checked && rec->owner_ref_checked &&
3977             rec->extent_item_refs == rec->refs && rec->refs > 0 &&
3978             rec->num_duplicates == 0 && !all_backpointers_checked(rec, 0) &&
3979             !rec->bad_full_backref && !rec->crossing_stripes &&
3980             !rec->wrong_chunk_type) {
3981                 remove_cache_extent(extent_cache, &rec->cache);
3982                 free_all_extent_backrefs(rec);
3983                 list_del_init(&rec->list);
3984                 free(rec);
3985         }
3986         return 0;
3987 }
3988
3989 static int check_owner_ref(struct btrfs_root *root,
3990                             struct extent_record *rec,
3991                             struct extent_buffer *buf)
3992 {
3993         struct extent_backref *node;
3994         struct tree_backref *back;
3995         struct btrfs_root *ref_root;
3996         struct btrfs_key key;
3997         struct btrfs_path path;
3998         struct extent_buffer *parent;
3999         int level;
4000         int found = 0;
4001         int ret;
4002
4003         list_for_each_entry(node, &rec->backrefs, list) {
4004                 if (node->is_data)
4005                         continue;
4006                 if (!node->found_ref)
4007                         continue;
4008                 if (node->full_backref)
4009                         continue;
4010                 back = to_tree_backref(node);
4011                 if (btrfs_header_owner(buf) == back->root)
4012                         return 0;
4013         }
4014         BUG_ON(rec->is_root);
4015
4016         /* try to find the block by search corresponding fs tree */
4017         key.objectid = btrfs_header_owner(buf);
4018         key.type = BTRFS_ROOT_ITEM_KEY;
4019         key.offset = (u64)-1;
4020
4021         ref_root = btrfs_read_fs_root(root->fs_info, &key);
4022         if (IS_ERR(ref_root))
4023                 return 1;
4024
4025         level = btrfs_header_level(buf);
4026         if (level == 0)
4027                 btrfs_item_key_to_cpu(buf, &key, 0);
4028         else
4029                 btrfs_node_key_to_cpu(buf, &key, 0);
4030
4031         btrfs_init_path(&path);
4032         path.lowest_level = level + 1;
4033         ret = btrfs_search_slot(NULL, ref_root, &key, &path, 0, 0);
4034         if (ret < 0)
4035                 return 0;
4036
4037         parent = path.nodes[level + 1];
4038         if (parent && buf->start == btrfs_node_blockptr(parent,
4039                                                         path.slots[level + 1]))
4040                 found = 1;
4041
4042         btrfs_release_path(&path);
4043         return found ? 0 : 1;
4044 }
4045
4046 static int is_extent_tree_record(struct extent_record *rec)
4047 {
4048         struct list_head *cur = rec->backrefs.next;
4049         struct extent_backref *node;
4050         struct tree_backref *back;
4051         int is_extent = 0;
4052
4053         while(cur != &rec->backrefs) {
4054                 node = to_extent_backref(cur);
4055                 cur = cur->next;
4056                 if (node->is_data)
4057                         return 0;
4058                 back = to_tree_backref(node);
4059                 if (node->full_backref)
4060                         return 0;
4061                 if (back->root == BTRFS_EXTENT_TREE_OBJECTID)
4062                         is_extent = 1;
4063         }
4064         return is_extent;
4065 }
4066
4067
4068 static int record_bad_block_io(struct btrfs_fs_info *info,
4069                                struct cache_tree *extent_cache,
4070                                u64 start, u64 len)
4071 {
4072         struct extent_record *rec;
4073         struct cache_extent *cache;
4074         struct btrfs_key key;
4075
4076         cache = lookup_cache_extent(extent_cache, start, len);
4077         if (!cache)
4078                 return 0;
4079
4080         rec = container_of(cache, struct extent_record, cache);
4081         if (!is_extent_tree_record(rec))
4082                 return 0;
4083
4084         btrfs_disk_key_to_cpu(&key, &rec->parent_key);
4085         return btrfs_add_corrupt_extent_record(info, &key, start, len, 0);
4086 }
4087
4088 static int swap_values(struct btrfs_root *root, struct btrfs_path *path,
4089                        struct extent_buffer *buf, int slot)
4090 {
4091         if (btrfs_header_level(buf)) {
4092                 struct btrfs_key_ptr ptr1, ptr2;
4093
4094                 read_extent_buffer(buf, &ptr1, btrfs_node_key_ptr_offset(slot),
4095                                    sizeof(struct btrfs_key_ptr));
4096                 read_extent_buffer(buf, &ptr2,
4097                                    btrfs_node_key_ptr_offset(slot + 1),
4098                                    sizeof(struct btrfs_key_ptr));
4099                 write_extent_buffer(buf, &ptr1,
4100                                     btrfs_node_key_ptr_offset(slot + 1),
4101                                     sizeof(struct btrfs_key_ptr));
4102                 write_extent_buffer(buf, &ptr2,
4103                                     btrfs_node_key_ptr_offset(slot),
4104                                     sizeof(struct btrfs_key_ptr));
4105                 if (slot == 0) {
4106                         struct btrfs_disk_key key;
4107                         btrfs_node_key(buf, &key, 0);
4108                         btrfs_fixup_low_keys(root, path, &key,
4109                                              btrfs_header_level(buf) + 1);
4110                 }
4111         } else {
4112                 struct btrfs_item *item1, *item2;
4113                 struct btrfs_key k1, k2;
4114                 char *item1_data, *item2_data;
4115                 u32 item1_offset, item2_offset, item1_size, item2_size;
4116
4117                 item1 = btrfs_item_nr(slot);
4118                 item2 = btrfs_item_nr(slot + 1);
4119                 btrfs_item_key_to_cpu(buf, &k1, slot);
4120                 btrfs_item_key_to_cpu(buf, &k2, slot + 1);
4121                 item1_offset = btrfs_item_offset(buf, item1);
4122                 item2_offset = btrfs_item_offset(buf, item2);
4123                 item1_size = btrfs_item_size(buf, item1);
4124                 item2_size = btrfs_item_size(buf, item2);
4125
4126                 item1_data = malloc(item1_size);
4127                 if (!item1_data)
4128                         return -ENOMEM;
4129                 item2_data = malloc(item2_size);
4130                 if (!item2_data) {
4131                         free(item1_data);
4132                         return -ENOMEM;
4133                 }
4134
4135                 read_extent_buffer(buf, item1_data, item1_offset, item1_size);
4136                 read_extent_buffer(buf, item2_data, item2_offset, item2_size);
4137
4138                 write_extent_buffer(buf, item1_data, item2_offset, item2_size);
4139                 write_extent_buffer(buf, item2_data, item1_offset, item1_size);
4140                 free(item1_data);
4141                 free(item2_data);
4142
4143                 btrfs_set_item_offset(buf, item1, item2_offset);
4144                 btrfs_set_item_offset(buf, item2, item1_offset);
4145                 btrfs_set_item_size(buf, item1, item2_size);
4146                 btrfs_set_item_size(buf, item2, item1_size);
4147
4148                 path->slots[0] = slot;
4149                 btrfs_set_item_key_unsafe(root, path, &k2);
4150                 path->slots[0] = slot + 1;
4151                 btrfs_set_item_key_unsafe(root, path, &k1);
4152         }
4153         return 0;
4154 }
4155
4156 static int fix_key_order(struct btrfs_trans_handle *trans,
4157                          struct btrfs_root *root,
4158                          struct btrfs_path *path)
4159 {
4160         struct extent_buffer *buf;
4161         struct btrfs_key k1, k2;
4162         int i;
4163         int level = path->lowest_level;
4164         int ret = -EIO;
4165
4166         buf = path->nodes[level];
4167         for (i = 0; i < btrfs_header_nritems(buf) - 1; i++) {
4168                 if (level) {
4169                         btrfs_node_key_to_cpu(buf, &k1, i);
4170                         btrfs_node_key_to_cpu(buf, &k2, i + 1);
4171                 } else {
4172                         btrfs_item_key_to_cpu(buf, &k1, i);
4173                         btrfs_item_key_to_cpu(buf, &k2, i + 1);
4174                 }
4175                 if (btrfs_comp_cpu_keys(&k1, &k2) < 0)
4176                         continue;
4177                 ret = swap_values(root, path, buf, i);
4178                 if (ret)
4179                         break;
4180                 btrfs_mark_buffer_dirty(buf);
4181                 i = 0;
4182         }
4183         return ret;
4184 }
4185
4186 static int delete_bogus_item(struct btrfs_trans_handle *trans,
4187                              struct btrfs_root *root,
4188                              struct btrfs_path *path,
4189                              struct extent_buffer *buf, int slot)
4190 {
4191         struct btrfs_key key;
4192         int nritems = btrfs_header_nritems(buf);
4193
4194         btrfs_item_key_to_cpu(buf, &key, slot);
4195
4196         /* These are all the keys we can deal with missing. */
4197         if (key.type != BTRFS_DIR_INDEX_KEY &&
4198             key.type != BTRFS_EXTENT_ITEM_KEY &&
4199             key.type != BTRFS_METADATA_ITEM_KEY &&
4200             key.type != BTRFS_TREE_BLOCK_REF_KEY &&
4201             key.type != BTRFS_EXTENT_DATA_REF_KEY)
4202                 return -1;
4203
4204         printf("Deleting bogus item [%llu,%u,%llu] at slot %d on block %llu\n",
4205                (unsigned long long)key.objectid, key.type,
4206                (unsigned long long)key.offset, slot, buf->start);
4207         memmove_extent_buffer(buf, btrfs_item_nr_offset(slot),
4208                               btrfs_item_nr_offset(slot + 1),
4209                               sizeof(struct btrfs_item) *
4210                               (nritems - slot - 1));
4211         btrfs_set_header_nritems(buf, nritems - 1);
4212         if (slot == 0) {
4213                 struct btrfs_disk_key disk_key;
4214
4215                 btrfs_item_key(buf, &disk_key, 0);
4216                 btrfs_fixup_low_keys(root, path, &disk_key, 1);
4217         }
4218         btrfs_mark_buffer_dirty(buf);
4219         return 0;
4220 }
4221
4222 static int fix_item_offset(struct btrfs_trans_handle *trans,
4223                            struct btrfs_root *root,
4224                            struct btrfs_path *path)
4225 {
4226         struct extent_buffer *buf;
4227         int i;
4228         int ret = 0;
4229
4230         /* We should only get this for leaves */
4231         BUG_ON(path->lowest_level);
4232         buf = path->nodes[0];
4233 again:
4234         for (i = 0; i < btrfs_header_nritems(buf); i++) {
4235                 unsigned int shift = 0, offset;
4236
4237                 if (i == 0 && btrfs_item_end_nr(buf, i) !=
4238                     BTRFS_LEAF_DATA_SIZE(root)) {
4239                         if (btrfs_item_end_nr(buf, i) >
4240                             BTRFS_LEAF_DATA_SIZE(root)) {
4241                                 ret = delete_bogus_item(trans, root, path,
4242                                                         buf, i);
4243                                 if (!ret)
4244                                         goto again;
4245                                 fprintf(stderr, "item is off the end of the "
4246                                         "leaf, can't fix\n");
4247                                 ret = -EIO;
4248                                 break;
4249                         }
4250                         shift = BTRFS_LEAF_DATA_SIZE(root) -
4251                                 btrfs_item_end_nr(buf, i);
4252                 } else if (i > 0 && btrfs_item_end_nr(buf, i) !=
4253                            btrfs_item_offset_nr(buf, i - 1)) {
4254                         if (btrfs_item_end_nr(buf, i) >
4255                             btrfs_item_offset_nr(buf, i - 1)) {
4256                                 ret = delete_bogus_item(trans, root, path,
4257                                                         buf, i);
4258                                 if (!ret)
4259                                         goto again;
4260                                 fprintf(stderr, "items overlap, can't fix\n");
4261                                 ret = -EIO;
4262                                 break;
4263                         }
4264                         shift = btrfs_item_offset_nr(buf, i - 1) -
4265                                 btrfs_item_end_nr(buf, i);
4266                 }
4267                 if (!shift)
4268                         continue;
4269
4270                 printf("Shifting item nr %d by %u bytes in block %llu\n",
4271                        i, shift, (unsigned long long)buf->start);
4272                 offset = btrfs_item_offset_nr(buf, i);
4273                 memmove_extent_buffer(buf,
4274                                       btrfs_leaf_data(buf) + offset + shift,
4275                                       btrfs_leaf_data(buf) + offset,
4276                                       btrfs_item_size_nr(buf, i));
4277                 btrfs_set_item_offset(buf, btrfs_item_nr(i),
4278                                       offset + shift);
4279                 btrfs_mark_buffer_dirty(buf);
4280         }
4281
4282         /*
4283          * We may have moved things, in which case we want to exit so we don't
4284          * write those changes out.  Once we have proper abort functionality in
4285          * progs this can be changed to something nicer.
4286          */
4287         BUG_ON(ret);
4288         return ret;
4289 }
4290
4291 /*
4292  * Attempt to fix basic block failures.  If we can't fix it for whatever reason
4293  * then just return -EIO.
4294  */
4295 static int try_to_fix_bad_block(struct btrfs_root *root,
4296                                 struct extent_buffer *buf,
4297                                 enum btrfs_tree_block_status status)
4298 {
4299         struct btrfs_trans_handle *trans;
4300         struct ulist *roots;
4301         struct ulist_node *node;
4302         struct btrfs_root *search_root;
4303         struct btrfs_path path;
4304         struct ulist_iterator iter;
4305         struct btrfs_key root_key, key;
4306         int ret;
4307
4308         if (status != BTRFS_TREE_BLOCK_BAD_KEY_ORDER &&
4309             status != BTRFS_TREE_BLOCK_INVALID_OFFSETS)
4310                 return -EIO;
4311
4312         ret = btrfs_find_all_roots(NULL, root->fs_info, buf->start, 0, &roots);
4313         if (ret)
4314                 return -EIO;
4315
4316         btrfs_init_path(&path);
4317         ULIST_ITER_INIT(&iter);
4318         while ((node = ulist_next(roots, &iter))) {
4319                 root_key.objectid = node->val;
4320                 root_key.type = BTRFS_ROOT_ITEM_KEY;
4321                 root_key.offset = (u64)-1;
4322
4323                 search_root = btrfs_read_fs_root(root->fs_info, &root_key);
4324                 if (IS_ERR(root)) {
4325                         ret = -EIO;
4326                         break;
4327                 }
4328
4329
4330                 trans = btrfs_start_transaction(search_root, 0);
4331                 if (IS_ERR(trans)) {
4332                         ret = PTR_ERR(trans);
4333                         break;
4334                 }
4335
4336                 path.lowest_level = btrfs_header_level(buf);
4337                 path.skip_check_block = 1;
4338                 if (path.lowest_level)
4339                         btrfs_node_key_to_cpu(buf, &key, 0);
4340                 else
4341                         btrfs_item_key_to_cpu(buf, &key, 0);
4342                 ret = btrfs_search_slot(trans, search_root, &key, &path, 0, 1);
4343                 if (ret) {
4344                         ret = -EIO;
4345                         btrfs_commit_transaction(trans, search_root);
4346                         break;
4347                 }
4348                 if (status == BTRFS_TREE_BLOCK_BAD_KEY_ORDER)
4349                         ret = fix_key_order(trans, search_root, &path);
4350                 else if (status == BTRFS_TREE_BLOCK_INVALID_OFFSETS)
4351                         ret = fix_item_offset(trans, search_root, &path);
4352                 if (ret) {
4353                         btrfs_commit_transaction(trans, search_root);
4354                         break;
4355                 }
4356                 btrfs_release_path(&path);
4357                 btrfs_commit_transaction(trans, search_root);
4358         }
4359         ulist_free(roots);
4360         btrfs_release_path(&path);
4361         return ret;
4362 }
4363
4364 static int check_block(struct btrfs_root *root,
4365                        struct cache_tree *extent_cache,
4366                        struct extent_buffer *buf, u64 flags)
4367 {
4368         struct extent_record *rec;
4369         struct cache_extent *cache;
4370         struct btrfs_key key;
4371         enum btrfs_tree_block_status status;
4372         int ret = 0;
4373         int level;
4374
4375         cache = lookup_cache_extent(extent_cache, buf->start, buf->len);
4376         if (!cache)
4377                 return 1;
4378         rec = container_of(cache, struct extent_record, cache);
4379         rec->generation = btrfs_header_generation(buf);
4380
4381         level = btrfs_header_level(buf);
4382         if (btrfs_header_nritems(buf) > 0) {
4383
4384                 if (level == 0)
4385                         btrfs_item_key_to_cpu(buf, &key, 0);
4386                 else
4387                         btrfs_node_key_to_cpu(buf, &key, 0);
4388
4389                 rec->info_objectid = key.objectid;
4390         }
4391         rec->info_level = level;
4392
4393         if (btrfs_is_leaf(buf))
4394                 status = btrfs_check_leaf(root, &rec->parent_key, buf);
4395         else
4396                 status = btrfs_check_node(root, &rec->parent_key, buf);
4397
4398         if (status != BTRFS_TREE_BLOCK_CLEAN) {
4399                 if (repair)
4400                         status = try_to_fix_bad_block(root, buf, status);
4401                 if (status != BTRFS_TREE_BLOCK_CLEAN) {
4402                         ret = -EIO;
4403                         fprintf(stderr, "bad block %llu\n",
4404                                 (unsigned long long)buf->start);
4405                 } else {
4406                         /*
4407                          * Signal to callers we need to start the scan over
4408                          * again since we'll have cowed blocks.
4409                          */
4410                         ret = -EAGAIN;
4411                 }
4412         } else {
4413                 rec->content_checked = 1;
4414                 if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4415                         rec->owner_ref_checked = 1;
4416                 else {
4417                         ret = check_owner_ref(root, rec, buf);
4418                         if (!ret)
4419                                 rec->owner_ref_checked = 1;
4420                 }
4421         }
4422         if (!ret)
4423                 maybe_free_extent_rec(extent_cache, rec);
4424         return ret;
4425 }
4426
4427 static struct tree_backref *find_tree_backref(struct extent_record *rec,
4428                                                 u64 parent, u64 root)
4429 {
4430         struct list_head *cur = rec->backrefs.next;
4431         struct extent_backref *node;
4432         struct tree_backref *back;
4433
4434         while(cur != &rec->backrefs) {
4435                 node = to_extent_backref(cur);
4436                 cur = cur->next;
4437                 if (node->is_data)
4438                         continue;
4439                 back = to_tree_backref(node);
4440                 if (parent > 0) {
4441                         if (!node->full_backref)
4442                                 continue;
4443                         if (parent == back->parent)
4444                                 return back;
4445                 } else {
4446                         if (node->full_backref)
4447                                 continue;
4448                         if (back->root == root)
4449                                 return back;
4450                 }
4451         }
4452         return NULL;
4453 }
4454
4455 static struct tree_backref *alloc_tree_backref(struct extent_record *rec,
4456                                                 u64 parent, u64 root)
4457 {
4458         struct tree_backref *ref = malloc(sizeof(*ref));
4459
4460         if (!ref)
4461                 return NULL;
4462         memset(&ref->node, 0, sizeof(ref->node));
4463         if (parent > 0) {
4464                 ref->parent = parent;
4465                 ref->node.full_backref = 1;
4466         } else {
4467                 ref->root = root;
4468                 ref->node.full_backref = 0;
4469         }
4470         list_add_tail(&ref->node.list, &rec->backrefs);
4471
4472         return ref;
4473 }
4474
4475 static struct data_backref *find_data_backref(struct extent_record *rec,
4476                                                 u64 parent, u64 root,
4477                                                 u64 owner, u64 offset,
4478                                                 int found_ref,
4479                                                 u64 disk_bytenr, u64 bytes)
4480 {
4481         struct list_head *cur = rec->backrefs.next;
4482         struct extent_backref *node;
4483         struct data_backref *back;
4484
4485         while(cur != &rec->backrefs) {
4486                 node = to_extent_backref(cur);
4487                 cur = cur->next;
4488                 if (!node->is_data)
4489                         continue;
4490                 back = to_data_backref(node);
4491                 if (parent > 0) {
4492                         if (!node->full_backref)
4493                                 continue;
4494                         if (parent == back->parent)
4495                                 return back;
4496                 } else {
4497                         if (node->full_backref)
4498                                 continue;
4499                         if (back->root == root && back->owner == owner &&
4500                             back->offset == offset) {
4501                                 if (found_ref && node->found_ref &&
4502                                     (back->bytes != bytes ||
4503                                     back->disk_bytenr != disk_bytenr))
4504                                         continue;
4505                                 return back;
4506                         }
4507                 }
4508         }
4509         return NULL;
4510 }
4511
4512 static struct data_backref *alloc_data_backref(struct extent_record *rec,
4513                                                 u64 parent, u64 root,
4514                                                 u64 owner, u64 offset,
4515                                                 u64 max_size)
4516 {
4517         struct data_backref *ref = malloc(sizeof(*ref));
4518
4519         if (!ref)
4520                 return NULL;
4521         memset(&ref->node, 0, sizeof(ref->node));
4522         ref->node.is_data = 1;
4523
4524         if (parent > 0) {
4525                 ref->parent = parent;
4526                 ref->owner = 0;
4527                 ref->offset = 0;
4528                 ref->node.full_backref = 1;
4529         } else {
4530                 ref->root = root;
4531                 ref->owner = owner;
4532                 ref->offset = offset;
4533                 ref->node.full_backref = 0;
4534         }
4535         ref->bytes = max_size;
4536         ref->found_ref = 0;
4537         ref->num_refs = 0;
4538         list_add_tail(&ref->node.list, &rec->backrefs);
4539         if (max_size > rec->max_size)
4540                 rec->max_size = max_size;
4541         return ref;
4542 }
4543
4544 /* Check if the type of extent matches with its chunk */
4545 static void check_extent_type(struct extent_record *rec)
4546 {
4547         struct btrfs_block_group_cache *bg_cache;
4548
4549         bg_cache = btrfs_lookup_first_block_group(global_info, rec->start);
4550         if (!bg_cache)
4551                 return;
4552
4553         /* data extent, check chunk directly*/
4554         if (!rec->metadata) {
4555                 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_DATA))
4556                         rec->wrong_chunk_type = 1;
4557                 return;
4558         }
4559
4560         /* metadata extent, check the obvious case first */
4561         if (!(bg_cache->flags & (BTRFS_BLOCK_GROUP_SYSTEM |
4562                                  BTRFS_BLOCK_GROUP_METADATA))) {
4563                 rec->wrong_chunk_type = 1;
4564                 return;
4565         }
4566
4567         /*
4568          * Check SYSTEM extent, as it's also marked as metadata, we can only
4569          * make sure it's a SYSTEM extent by its backref
4570          */
4571         if (!list_empty(&rec->backrefs)) {
4572                 struct extent_backref *node;
4573                 struct tree_backref *tback;
4574                 u64 bg_type;
4575
4576                 node = to_extent_backref(rec->backrefs.next);
4577                 if (node->is_data) {
4578                         /* tree block shouldn't have data backref */
4579                         rec->wrong_chunk_type = 1;
4580                         return;
4581                 }
4582                 tback = container_of(node, struct tree_backref, node);
4583
4584                 if (tback->root == BTRFS_CHUNK_TREE_OBJECTID)
4585                         bg_type = BTRFS_BLOCK_GROUP_SYSTEM;
4586                 else
4587                         bg_type = BTRFS_BLOCK_GROUP_METADATA;
4588                 if (!(bg_cache->flags & bg_type))
4589                         rec->wrong_chunk_type = 1;
4590         }
4591 }
4592
4593 /*
4594  * Allocate a new extent record, fill default values from @tmpl and insert int
4595  * @extent_cache. Caller is supposed to make sure the [start,nr) is not in
4596  * the cache, otherwise it fails.
4597  */
4598 static int add_extent_rec_nolookup(struct cache_tree *extent_cache,
4599                 struct extent_record *tmpl)
4600 {
4601         struct extent_record *rec;
4602         int ret = 0;
4603
4604         rec = malloc(sizeof(*rec));
4605         if (!rec)
4606                 return -ENOMEM;
4607         rec->start = tmpl->start;
4608         rec->max_size = tmpl->max_size;
4609         rec->nr = max(tmpl->nr, tmpl->max_size);
4610         rec->found_rec = tmpl->found_rec;
4611         rec->content_checked = tmpl->content_checked;
4612         rec->owner_ref_checked = tmpl->owner_ref_checked;
4613         rec->num_duplicates = 0;
4614         rec->metadata = tmpl->metadata;
4615         rec->flag_block_full_backref = FLAG_UNSET;
4616         rec->bad_full_backref = 0;
4617         rec->crossing_stripes = 0;
4618         rec->wrong_chunk_type = 0;
4619         rec->is_root = tmpl->is_root;
4620         rec->refs = tmpl->refs;
4621         rec->extent_item_refs = tmpl->extent_item_refs;
4622         rec->parent_generation = tmpl->parent_generation;
4623         INIT_LIST_HEAD(&rec->backrefs);
4624         INIT_LIST_HEAD(&rec->dups);
4625         INIT_LIST_HEAD(&rec->list);
4626         memcpy(&rec->parent_key, &tmpl->parent_key, sizeof(tmpl->parent_key));
4627         rec->cache.start = tmpl->start;
4628         rec->cache.size = tmpl->nr;
4629         ret = insert_cache_extent(extent_cache, &rec->cache);
4630         if (ret) {
4631                 free(rec);
4632                 return ret;
4633         }
4634         bytes_used += rec->nr;
4635
4636         if (tmpl->metadata)
4637                 rec->crossing_stripes = check_crossing_stripes(global_info,
4638                                 rec->start, global_info->tree_root->nodesize);
4639         check_extent_type(rec);
4640         return ret;
4641 }
4642
4643 /*
4644  * Lookup and modify an extent, some values of @tmpl are interpreted verbatim,
4645  * some are hints:
4646  * - refs              - if found, increase refs
4647  * - is_root           - if found, set
4648  * - content_checked   - if found, set
4649  * - owner_ref_checked - if found, set
4650  *
4651  * If not found, create a new one, initialize and insert.
4652  */
4653 static int add_extent_rec(struct cache_tree *extent_cache,
4654                 struct extent_record *tmpl)
4655 {
4656         struct extent_record *rec;
4657         struct cache_extent *cache;
4658         int ret = 0;
4659         int dup = 0;
4660
4661         cache = lookup_cache_extent(extent_cache, tmpl->start, tmpl->nr);
4662         if (cache) {
4663                 rec = container_of(cache, struct extent_record, cache);
4664                 if (tmpl->refs)
4665                         rec->refs++;
4666                 if (rec->nr == 1)
4667                         rec->nr = max(tmpl->nr, tmpl->max_size);
4668
4669                 /*
4670                  * We need to make sure to reset nr to whatever the extent
4671                  * record says was the real size, this way we can compare it to
4672                  * the backrefs.
4673                  */
4674                 if (tmpl->found_rec) {
4675                         if (tmpl->start != rec->start || rec->found_rec) {
4676                                 struct extent_record *tmp;
4677
4678                                 dup = 1;
4679                                 if (list_empty(&rec->list))
4680                                         list_add_tail(&rec->list,
4681                                                       &duplicate_extents);
4682
4683                                 /*
4684                                  * We have to do this song and dance in case we
4685                                  * find an extent record that falls inside of
4686                                  * our current extent record but does not have
4687                                  * the same objectid.
4688                                  */
4689                                 tmp = malloc(sizeof(*tmp));
4690                                 if (!tmp)
4691                                         return -ENOMEM;
4692                                 tmp->start = tmpl->start;
4693                                 tmp->max_size = tmpl->max_size;
4694                                 tmp->nr = tmpl->nr;
4695                                 tmp->found_rec = 1;
4696                                 tmp->metadata = tmpl->metadata;
4697                                 tmp->extent_item_refs = tmpl->extent_item_refs;
4698                                 INIT_LIST_HEAD(&tmp->list);
4699                                 list_add_tail(&tmp->list, &rec->dups);
4700                                 rec->num_duplicates++;
4701                         } else {
4702                                 rec->nr = tmpl->nr;
4703                                 rec->found_rec = 1;
4704                         }
4705                 }
4706
4707                 if (tmpl->extent_item_refs && !dup) {
4708                         if (rec->extent_item_refs) {
4709                                 fprintf(stderr, "block %llu rec "
4710                                         "extent_item_refs %llu, passed %llu\n",
4711                                         (unsigned long long)tmpl->start,
4712                                         (unsigned long long)
4713                                                         rec->extent_item_refs,
4714                                         (unsigned long long)tmpl->extent_item_refs);
4715                         }
4716                         rec->extent_item_refs = tmpl->extent_item_refs;
4717                 }
4718                 if (tmpl->is_root)
4719                         rec->is_root = 1;
4720                 if (tmpl->content_checked)
4721                         rec->content_checked = 1;
4722                 if (tmpl->owner_ref_checked)
4723                         rec->owner_ref_checked = 1;
4724                 memcpy(&rec->parent_key, &tmpl->parent_key,
4725                                 sizeof(tmpl->parent_key));
4726                 if (tmpl->parent_generation)
4727                         rec->parent_generation = tmpl->parent_generation;
4728                 if (rec->max_size < tmpl->max_size)
4729                         rec->max_size = tmpl->max_size;
4730
4731                 /*
4732                  * A metadata extent can't cross stripe_len boundary, otherwise
4733                  * kernel scrub won't be able to handle it.
4734                  * As now stripe_len is fixed to BTRFS_STRIPE_LEN, just check
4735                  * it.
4736                  */
4737                 if (tmpl->metadata)
4738                         rec->crossing_stripes = check_crossing_stripes(
4739                                         global_info, rec->start,
4740                                         global_info->tree_root->nodesize);
4741                 check_extent_type(rec);
4742                 maybe_free_extent_rec(extent_cache, rec);
4743                 return ret;
4744         }
4745
4746         ret = add_extent_rec_nolookup(extent_cache, tmpl);
4747
4748         return ret;
4749 }
4750
4751 static int add_tree_backref(struct cache_tree *extent_cache, u64 bytenr,
4752                             u64 parent, u64 root, int found_ref)
4753 {
4754         struct extent_record *rec;
4755         struct tree_backref *back;
4756         struct cache_extent *cache;
4757         int ret;
4758
4759         cache = lookup_cache_extent(extent_cache, bytenr, 1);
4760         if (!cache) {
4761                 struct extent_record tmpl;
4762
4763                 memset(&tmpl, 0, sizeof(tmpl));
4764                 tmpl.start = bytenr;
4765                 tmpl.nr = 1;
4766                 tmpl.metadata = 1;
4767
4768                 ret = add_extent_rec_nolookup(extent_cache, &tmpl);
4769                 if (ret)
4770                         return ret;
4771
4772                 /* really a bug in cache_extent implement now */
4773                 cache = lookup_cache_extent(extent_cache, bytenr, 1);
4774                 if (!cache)
4775                         return -ENOENT;
4776         }
4777
4778         rec = container_of(cache, struct extent_record, cache);
4779         if (rec->start != bytenr) {
4780                 /*
4781                  * Several cause, from unaligned bytenr to over lapping extents
4782                  */
4783                 return -EEXIST;
4784         }
4785
4786         back = find_tree_backref(rec, parent, root);
4787         if (!back) {
4788                 back = alloc_tree_backref(rec, parent, root);
4789                 if (!back)
4790                         return -ENOMEM;
4791         }
4792
4793         if (found_ref) {
4794                 if (back->node.found_ref) {
4795                         fprintf(stderr, "Extent back ref already exists "
4796                                 "for %llu parent %llu root %llu \n",
4797                                 (unsigned long long)bytenr,
4798                                 (unsigned long long)parent,
4799                                 (unsigned long long)root);
4800                 }
4801                 back->node.found_ref = 1;
4802         } else {
4803                 if (back->node.found_extent_tree) {
4804                         fprintf(stderr, "Extent back ref already exists "
4805                                 "for %llu parent %llu root %llu \n",
4806                                 (unsigned long long)bytenr,
4807                                 (unsigned long long)parent,
4808                                 (unsigned long long)root);
4809                 }
4810                 back->node.found_extent_tree = 1;
4811         }
4812         check_extent_type(rec);
4813         maybe_free_extent_rec(extent_cache, rec);
4814         return 0;
4815 }
4816
4817 static int add_data_backref(struct cache_tree *extent_cache, u64 bytenr,
4818                             u64 parent, u64 root, u64 owner, u64 offset,
4819                             u32 num_refs, int found_ref, u64 max_size)
4820 {
4821         struct extent_record *rec;
4822         struct data_backref *back;
4823         struct cache_extent *cache;
4824         int ret;
4825
4826         cache = lookup_cache_extent(extent_cache, bytenr, 1);
4827         if (!cache) {
4828                 struct extent_record tmpl;
4829
4830                 memset(&tmpl, 0, sizeof(tmpl));
4831                 tmpl.start = bytenr;
4832                 tmpl.nr = 1;
4833                 tmpl.max_size = max_size;
4834
4835                 ret = add_extent_rec_nolookup(extent_cache, &tmpl);
4836                 if (ret)
4837                         return ret;
4838
4839                 cache = lookup_cache_extent(extent_cache, bytenr, 1);
4840                 if (!cache)
4841                         abort();
4842         }
4843
4844         rec = container_of(cache, struct extent_record, cache);
4845         if (rec->max_size < max_size)
4846                 rec->max_size = max_size;
4847
4848         /*
4849          * If found_ref is set then max_size is the real size and must match the
4850          * existing refs.  So if we have already found a ref then we need to
4851          * make sure that this ref matches the existing one, otherwise we need
4852          * to add a new backref so we can notice that the backrefs don't match
4853          * and we need to figure out who is telling the truth.  This is to
4854          * account for that awful fsync bug I introduced where we'd end up with
4855          * a btrfs_file_extent_item that would have its length include multiple
4856          * prealloc extents or point inside of a prealloc extent.
4857          */
4858         back = find_data_backref(rec, parent, root, owner, offset, found_ref,
4859                                  bytenr, max_size);
4860         if (!back) {
4861                 back = alloc_data_backref(rec, parent, root, owner, offset,
4862                                           max_size);
4863                 BUG_ON(!back);
4864         }
4865
4866         if (found_ref) {
4867                 BUG_ON(num_refs != 1);
4868                 if (back->node.found_ref)
4869                         BUG_ON(back->bytes != max_size);
4870                 back->node.found_ref = 1;
4871                 back->found_ref += 1;
4872                 back->bytes = max_size;
4873                 back->disk_bytenr = bytenr;
4874                 rec->refs += 1;
4875                 rec->content_checked = 1;
4876                 rec->owner_ref_checked = 1;
4877         } else {
4878                 if (back->node.found_extent_tree) {
4879                         fprintf(stderr, "Extent back ref already exists "
4880                                 "for %llu parent %llu root %llu "
4881                                 "owner %llu offset %llu num_refs %lu\n",
4882                                 (unsigned long long)bytenr,
4883                                 (unsigned long long)parent,
4884                                 (unsigned long long)root,
4885                                 (unsigned long long)owner,
4886                                 (unsigned long long)offset,
4887                                 (unsigned long)num_refs);
4888                 }
4889                 back->num_refs = num_refs;
4890                 back->node.found_extent_tree = 1;
4891         }
4892         maybe_free_extent_rec(extent_cache, rec);
4893         return 0;
4894 }
4895
4896 static int add_pending(struct cache_tree *pending,
4897                        struct cache_tree *seen, u64 bytenr, u32 size)
4898 {
4899         int ret;
4900         ret = add_cache_extent(seen, bytenr, size);
4901         if (ret)
4902                 return ret;
4903         add_cache_extent(pending, bytenr, size);
4904         return 0;
4905 }
4906
4907 static int pick_next_pending(struct cache_tree *pending,
4908                         struct cache_tree *reada,
4909                         struct cache_tree *nodes,
4910                         u64 last, struct block_info *bits, int bits_nr,
4911                         int *reada_bits)
4912 {
4913         unsigned long node_start = last;
4914         struct cache_extent *cache;
4915         int ret;
4916
4917         cache = search_cache_extent(reada, 0);
4918         if (cache) {
4919                 bits[0].start = cache->start;
4920                 bits[0].size = cache->size;
4921                 *reada_bits = 1;
4922                 return 1;
4923         }
4924         *reada_bits = 0;
4925         if (node_start > 32768)
4926                 node_start -= 32768;
4927
4928         cache = search_cache_extent(nodes, node_start);
4929         if (!cache)
4930                 cache = search_cache_extent(nodes, 0);
4931
4932         if (!cache) {
4933                  cache = search_cache_extent(pending, 0);
4934                  if (!cache)
4935                          return 0;
4936                  ret = 0;
4937                  do {
4938                          bits[ret].start = cache->start;
4939                          bits[ret].size = cache->size;
4940                          cache = next_cache_extent(cache);
4941                          ret++;
4942                  } while (cache && ret < bits_nr);
4943                  return ret;
4944         }
4945
4946         ret = 0;
4947         do {
4948                 bits[ret].start = cache->start;
4949                 bits[ret].size = cache->size;
4950                 cache = next_cache_extent(cache);
4951                 ret++;
4952         } while (cache && ret < bits_nr);
4953
4954         if (bits_nr - ret > 8) {
4955                 u64 lookup = bits[0].start + bits[0].size;
4956                 struct cache_extent *next;
4957                 next = search_cache_extent(pending, lookup);
4958                 while(next) {
4959                         if (next->start - lookup > 32768)
4960                                 break;
4961                         bits[ret].start = next->start;
4962                         bits[ret].size = next->size;
4963                         lookup = next->start + next->size;
4964                         ret++;
4965                         if (ret == bits_nr)
4966                                 break;
4967                         next = next_cache_extent(next);
4968                         if (!next)
4969                                 break;
4970                 }
4971         }
4972         return ret;
4973 }
4974
4975 static void free_chunk_record(struct cache_extent *cache)
4976 {
4977         struct chunk_record *rec;
4978
4979         rec = container_of(cache, struct chunk_record, cache);
4980         list_del_init(&rec->list);
4981         list_del_init(&rec->dextents);
4982         free(rec);
4983 }
4984
4985 void free_chunk_cache_tree(struct cache_tree *chunk_cache)
4986 {
4987         cache_tree_free_extents(chunk_cache, free_chunk_record);
4988 }
4989
4990 static void free_device_record(struct rb_node *node)
4991 {
4992         struct device_record *rec;
4993
4994         rec = container_of(node, struct device_record, node);
4995         free(rec);
4996 }
4997
4998 FREE_RB_BASED_TREE(device_cache, free_device_record);
4999
5000 int insert_block_group_record(struct block_group_tree *tree,
5001                               struct block_group_record *bg_rec)
5002 {
5003         int ret;
5004
5005         ret = insert_cache_extent(&tree->tree, &bg_rec->cache);
5006         if (ret)
5007                 return ret;
5008
5009         list_add_tail(&bg_rec->list, &tree->block_groups);
5010         return 0;
5011 }
5012
5013 static void free_block_group_record(struct cache_extent *cache)
5014 {
5015         struct block_group_record *rec;
5016
5017         rec = container_of(cache, struct block_group_record, cache);
5018         list_del_init(&rec->list);
5019         free(rec);
5020 }
5021
5022 void free_block_group_tree(struct block_group_tree *tree)
5023 {
5024         cache_tree_free_extents(&tree->tree, free_block_group_record);
5025 }
5026
5027 int insert_device_extent_record(struct device_extent_tree *tree,
5028                                 struct device_extent_record *de_rec)
5029 {
5030         int ret;
5031
5032         /*
5033          * Device extent is a bit different from the other extents, because
5034          * the extents which belong to the different devices may have the
5035          * same start and size, so we need use the special extent cache
5036          * search/insert functions.
5037          */
5038         ret = insert_cache_extent2(&tree->tree, &de_rec->cache);
5039         if (ret)
5040                 return ret;
5041
5042         list_add_tail(&de_rec->chunk_list, &tree->no_chunk_orphans);
5043         list_add_tail(&de_rec->device_list, &tree->no_device_orphans);
5044         return 0;
5045 }
5046
5047 static void free_device_extent_record(struct cache_extent *cache)
5048 {
5049         struct device_extent_record *rec;
5050
5051         rec = container_of(cache, struct device_extent_record, cache);
5052         if (!list_empty(&rec->chunk_list))
5053                 list_del_init(&rec->chunk_list);
5054         if (!list_empty(&rec->device_list))
5055                 list_del_init(&rec->device_list);
5056         free(rec);
5057 }
5058
5059 void free_device_extent_tree(struct device_extent_tree *tree)
5060 {
5061         cache_tree_free_extents(&tree->tree, free_device_extent_record);
5062 }
5063
5064 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
5065 static int process_extent_ref_v0(struct cache_tree *extent_cache,
5066                                  struct extent_buffer *leaf, int slot)
5067 {
5068         struct btrfs_extent_ref_v0 *ref0;
5069         struct btrfs_key key;
5070         int ret;
5071
5072         btrfs_item_key_to_cpu(leaf, &key, slot);
5073         ref0 = btrfs_item_ptr(leaf, slot, struct btrfs_extent_ref_v0);
5074         if (btrfs_ref_objectid_v0(leaf, ref0) < BTRFS_FIRST_FREE_OBJECTID) {
5075                 ret = add_tree_backref(extent_cache, key.objectid, key.offset,
5076                                 0, 0);
5077         } else {
5078                 ret = add_data_backref(extent_cache, key.objectid, key.offset,
5079                                 0, 0, 0, btrfs_ref_count_v0(leaf, ref0), 0, 0);
5080         }
5081         return ret;
5082 }
5083 #endif
5084
5085 struct chunk_record *btrfs_new_chunk_record(struct extent_buffer *leaf,
5086                                             struct btrfs_key *key,
5087                                             int slot)
5088 {
5089         struct btrfs_chunk *ptr;
5090         struct chunk_record *rec;
5091         int num_stripes, i;
5092
5093         ptr = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
5094         num_stripes = btrfs_chunk_num_stripes(leaf, ptr);
5095
5096         rec = calloc(1, btrfs_chunk_record_size(num_stripes));
5097         if (!rec) {
5098                 fprintf(stderr, "memory allocation failed\n");
5099                 exit(-1);
5100         }
5101
5102         INIT_LIST_HEAD(&rec->list);
5103         INIT_LIST_HEAD(&rec->dextents);
5104         rec->bg_rec = NULL;
5105
5106         rec->cache.start = key->offset;
5107         rec->cache.size = btrfs_chunk_length(leaf, ptr);
5108
5109         rec->generation = btrfs_header_generation(leaf);
5110
5111         rec->objectid = key->objectid;
5112         rec->type = key->type;
5113         rec->offset = key->offset;
5114
5115         rec->length = rec->cache.size;
5116         rec->owner = btrfs_chunk_owner(leaf, ptr);
5117         rec->stripe_len = btrfs_chunk_stripe_len(leaf, ptr);
5118         rec->type_flags = btrfs_chunk_type(leaf, ptr);
5119         rec->io_width = btrfs_chunk_io_width(leaf, ptr);
5120         rec->io_align = btrfs_chunk_io_align(leaf, ptr);
5121         rec->sector_size = btrfs_chunk_sector_size(leaf, ptr);
5122         rec->num_stripes = num_stripes;
5123         rec->sub_stripes = btrfs_chunk_sub_stripes(leaf, ptr);
5124
5125         for (i = 0; i < rec->num_stripes; ++i) {
5126                 rec->stripes[i].devid =
5127                         btrfs_stripe_devid_nr(leaf, ptr, i);
5128                 rec->stripes[i].offset =
5129                         btrfs_stripe_offset_nr(leaf, ptr, i);
5130                 read_extent_buffer(leaf, rec->stripes[i].dev_uuid,
5131                                 (unsigned long)btrfs_stripe_dev_uuid_nr(ptr, i),
5132                                 BTRFS_UUID_SIZE);
5133         }
5134
5135         return rec;
5136 }
5137
5138 static int process_chunk_item(struct cache_tree *chunk_cache,
5139                               struct btrfs_key *key, struct extent_buffer *eb,
5140                               int slot)
5141 {
5142         struct chunk_record *rec;
5143         struct btrfs_chunk *chunk;
5144         int ret = 0;
5145
5146         chunk = btrfs_item_ptr(eb, slot, struct btrfs_chunk);
5147         /*
5148          * Do extra check for this chunk item,
5149          *
5150          * It's still possible one can craft a leaf with CHUNK_ITEM, with
5151          * wrong onwer(3) out of chunk tree, to pass both chunk tree check
5152          * and owner<->key_type check.
5153          */
5154         ret = btrfs_check_chunk_valid(global_info->tree_root, eb, chunk, slot,
5155                                       key->offset);
5156         if (ret < 0) {
5157                 error("chunk(%llu, %llu) is not valid, ignore it",
5158                       key->offset, btrfs_chunk_length(eb, chunk));
5159                 return 0;
5160         }
5161         rec = btrfs_new_chunk_record(eb, key, slot);
5162         ret = insert_cache_extent(chunk_cache, &rec->cache);
5163         if (ret) {
5164                 fprintf(stderr, "Chunk[%llu, %llu] existed.\n",
5165                         rec->offset, rec->length);
5166                 free(rec);
5167         }
5168
5169         return ret;
5170 }
5171
5172 static int process_device_item(struct rb_root *dev_cache,
5173                 struct btrfs_key *key, struct extent_buffer *eb, int slot)
5174 {
5175         struct btrfs_dev_item *ptr;
5176         struct device_record *rec;
5177         int ret = 0;
5178
5179         ptr = btrfs_item_ptr(eb,
5180                 slot, struct btrfs_dev_item);
5181
5182         rec = malloc(sizeof(*rec));
5183         if (!rec) {
5184                 fprintf(stderr, "memory allocation failed\n");
5185                 return -ENOMEM;
5186         }
5187
5188         rec->devid = key->offset;
5189         rec->generation = btrfs_header_generation(eb);
5190
5191         rec->objectid = key->objectid;
5192         rec->type = key->type;
5193         rec->offset = key->offset;
5194
5195         rec->devid = btrfs_device_id(eb, ptr);
5196         rec->total_byte = btrfs_device_total_bytes(eb, ptr);
5197         rec->byte_used = btrfs_device_bytes_used(eb, ptr);
5198
5199         ret = rb_insert(dev_cache, &rec->node, device_record_compare);
5200         if (ret) {
5201                 fprintf(stderr, "Device[%llu] existed.\n", rec->devid);
5202                 free(rec);
5203         }
5204
5205         return ret;
5206 }
5207
5208 struct block_group_record *
5209 btrfs_new_block_group_record(struct extent_buffer *leaf, struct btrfs_key *key,
5210                              int slot)
5211 {
5212         struct btrfs_block_group_item *ptr;
5213         struct block_group_record *rec;
5214
5215         rec = calloc(1, sizeof(*rec));
5216         if (!rec) {
5217                 fprintf(stderr, "memory allocation failed\n");
5218                 exit(-1);
5219         }
5220
5221         rec->cache.start = key->objectid;
5222         rec->cache.size = key->offset;
5223
5224         rec->generation = btrfs_header_generation(leaf);
5225
5226         rec->objectid = key->objectid;
5227         rec->type = key->type;
5228         rec->offset = key->offset;
5229
5230         ptr = btrfs_item_ptr(leaf, slot, struct btrfs_block_group_item);
5231         rec->flags = btrfs_disk_block_group_flags(leaf, ptr);
5232
5233         INIT_LIST_HEAD(&rec->list);
5234
5235         return rec;
5236 }
5237
5238 static int process_block_group_item(struct block_group_tree *block_group_cache,
5239                                     struct btrfs_key *key,
5240                                     struct extent_buffer *eb, int slot)
5241 {
5242         struct block_group_record *rec;
5243         int ret = 0;
5244
5245         rec = btrfs_new_block_group_record(eb, key, slot);
5246         ret = insert_block_group_record(block_group_cache, rec);
5247         if (ret) {
5248                 fprintf(stderr, "Block Group[%llu, %llu] existed.\n",
5249                         rec->objectid, rec->offset);
5250                 free(rec);
5251         }
5252
5253         return ret;
5254 }
5255
5256 struct device_extent_record *
5257 btrfs_new_device_extent_record(struct extent_buffer *leaf,
5258                                struct btrfs_key *key, int slot)
5259 {
5260         struct device_extent_record *rec;
5261         struct btrfs_dev_extent *ptr;
5262
5263         rec = calloc(1, sizeof(*rec));
5264         if (!rec) {
5265                 fprintf(stderr, "memory allocation failed\n");
5266                 exit(-1);
5267         }
5268
5269         rec->cache.objectid = key->objectid;
5270         rec->cache.start = key->offset;
5271
5272         rec->generation = btrfs_header_generation(leaf);
5273
5274         rec->objectid = key->objectid;
5275         rec->type = key->type;
5276         rec->offset = key->offset;
5277
5278         ptr = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
5279         rec->chunk_objecteid =
5280                 btrfs_dev_extent_chunk_objectid(leaf, ptr);
5281         rec->chunk_offset =
5282                 btrfs_dev_extent_chunk_offset(leaf, ptr);
5283         rec->length = btrfs_dev_extent_length(leaf, ptr);
5284         rec->cache.size = rec->length;
5285
5286         INIT_LIST_HEAD(&rec->chunk_list);
5287         INIT_LIST_HEAD(&rec->device_list);
5288
5289         return rec;
5290 }
5291
5292 static int
5293 process_device_extent_item(struct device_extent_tree *dev_extent_cache,
5294                            struct btrfs_key *key, struct extent_buffer *eb,
5295                            int slot)
5296 {
5297         struct device_extent_record *rec;
5298         int ret;
5299
5300         rec = btrfs_new_device_extent_record(eb, key, slot);
5301         ret = insert_device_extent_record(dev_extent_cache, rec);
5302         if (ret) {
5303                 fprintf(stderr,
5304                         "Device extent[%llu, %llu, %llu] existed.\n",
5305                         rec->objectid, rec->offset, rec->length);
5306                 free(rec);
5307         }
5308
5309         return ret;
5310 }
5311
5312 static int process_extent_item(struct btrfs_root *root,
5313                                struct cache_tree *extent_cache,
5314                                struct extent_buffer *eb, int slot)
5315 {
5316         struct btrfs_extent_item *ei;
5317         struct btrfs_extent_inline_ref *iref;
5318         struct btrfs_extent_data_ref *dref;
5319         struct btrfs_shared_data_ref *sref;
5320         struct btrfs_key key;
5321         struct extent_record tmpl;
5322         unsigned long end;
5323         unsigned long ptr;
5324         int ret;
5325         int type;
5326         u32 item_size = btrfs_item_size_nr(eb, slot);
5327         u64 refs = 0;
5328         u64 offset;
5329         u64 num_bytes;
5330         int metadata = 0;
5331
5332         btrfs_item_key_to_cpu(eb, &key, slot);
5333
5334         if (key.type == BTRFS_METADATA_ITEM_KEY) {
5335                 metadata = 1;
5336                 num_bytes = root->nodesize;
5337         } else {
5338                 num_bytes = key.offset;
5339         }
5340
5341         if (!IS_ALIGNED(key.objectid, root->sectorsize)) {
5342                 error("ignoring invalid extent, bytenr %llu is not aligned to %u",
5343                       key.objectid, root->sectorsize);
5344                 return -EIO;
5345         }
5346         if (item_size < sizeof(*ei)) {
5347 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
5348                 struct btrfs_extent_item_v0 *ei0;
5349                 BUG_ON(item_size != sizeof(*ei0));
5350                 ei0 = btrfs_item_ptr(eb, slot, struct btrfs_extent_item_v0);
5351                 refs = btrfs_extent_refs_v0(eb, ei0);
5352 #else
5353                 BUG();
5354 #endif
5355                 memset(&tmpl, 0, sizeof(tmpl));
5356                 tmpl.start = key.objectid;
5357                 tmpl.nr = num_bytes;
5358                 tmpl.extent_item_refs = refs;
5359                 tmpl.metadata = metadata;
5360                 tmpl.found_rec = 1;
5361                 tmpl.max_size = num_bytes;
5362
5363                 return add_extent_rec(extent_cache, &tmpl);
5364         }
5365
5366         ei = btrfs_item_ptr(eb, slot, struct btrfs_extent_item);
5367         refs = btrfs_extent_refs(eb, ei);
5368         if (btrfs_extent_flags(eb, ei) & BTRFS_EXTENT_FLAG_TREE_BLOCK)
5369                 metadata = 1;
5370         else
5371                 metadata = 0;
5372         if (metadata && num_bytes != root->nodesize) {
5373                 error("ignore invalid metadata extent, length %llu does not equal to %u",
5374                       num_bytes, root->nodesize);
5375                 return -EIO;
5376         }
5377         if (!metadata && !IS_ALIGNED(num_bytes, root->sectorsize)) {
5378                 error("ignore invalid data extent, length %llu is not aligned to %u",
5379                       num_bytes, root->sectorsize);
5380                 return -EIO;
5381         }
5382
5383         memset(&tmpl, 0, sizeof(tmpl));
5384         tmpl.start = key.objectid;
5385         tmpl.nr = num_bytes;
5386         tmpl.extent_item_refs = refs;
5387         tmpl.metadata = metadata;
5388         tmpl.found_rec = 1;
5389         tmpl.max_size = num_bytes;
5390         add_extent_rec(extent_cache, &tmpl);
5391
5392         ptr = (unsigned long)(ei + 1);
5393         if (btrfs_extent_flags(eb, ei) & BTRFS_EXTENT_FLAG_TREE_BLOCK &&
5394             key.type == BTRFS_EXTENT_ITEM_KEY)
5395                 ptr += sizeof(struct btrfs_tree_block_info);
5396
5397         end = (unsigned long)ei + item_size;
5398         while (ptr < end) {
5399                 iref = (struct btrfs_extent_inline_ref *)ptr;
5400                 type = btrfs_extent_inline_ref_type(eb, iref);
5401                 offset = btrfs_extent_inline_ref_offset(eb, iref);
5402                 switch (type) {
5403                 case BTRFS_TREE_BLOCK_REF_KEY:
5404                         ret = add_tree_backref(extent_cache, key.objectid,
5405                                         0, offset, 0);
5406                         if (ret < 0)
5407                                 error("add_tree_backref failed: %s",
5408                                       strerror(-ret));
5409                         break;
5410                 case BTRFS_SHARED_BLOCK_REF_KEY:
5411                         ret = add_tree_backref(extent_cache, key.objectid,
5412                                         offset, 0, 0);
5413                         if (ret < 0)
5414                                 error("add_tree_backref failed: %s",
5415                                       strerror(-ret));
5416                         break;
5417                 case BTRFS_EXTENT_DATA_REF_KEY:
5418                         dref = (struct btrfs_extent_data_ref *)(&iref->offset);
5419                         add_data_backref(extent_cache, key.objectid, 0,
5420                                         btrfs_extent_data_ref_root(eb, dref),
5421                                         btrfs_extent_data_ref_objectid(eb,
5422                                                                        dref),
5423                                         btrfs_extent_data_ref_offset(eb, dref),
5424                                         btrfs_extent_data_ref_count(eb, dref),
5425                                         0, num_bytes);
5426                         break;
5427                 case BTRFS_SHARED_DATA_REF_KEY:
5428                         sref = (struct btrfs_shared_data_ref *)(iref + 1);
5429                         add_data_backref(extent_cache, key.objectid, offset,
5430                                         0, 0, 0,
5431                                         btrfs_shared_data_ref_count(eb, sref),
5432                                         0, num_bytes);
5433                         break;
5434                 default:
5435                         fprintf(stderr, "corrupt extent record: key %Lu %u %Lu\n",
5436                                 key.objectid, key.type, num_bytes);
5437                         goto out;
5438                 }
5439                 ptr += btrfs_extent_inline_ref_size(type);
5440         }
5441         WARN_ON(ptr > end);
5442 out:
5443         return 0;
5444 }
5445
5446 static int check_cache_range(struct btrfs_root *root,
5447                              struct btrfs_block_group_cache *cache,
5448                              u64 offset, u64 bytes)
5449 {
5450         struct btrfs_free_space *entry;
5451         u64 *logical;
5452         u64 bytenr;
5453         int stripe_len;
5454         int i, nr, ret;
5455
5456         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
5457                 bytenr = btrfs_sb_offset(i);
5458                 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
5459                                        cache->key.objectid, bytenr, 0,
5460                                        &logical, &nr, &stripe_len);
5461                 if (ret)
5462                         return ret;
5463
5464                 while (nr--) {
5465                         if (logical[nr] + stripe_len <= offset)
5466                                 continue;
5467                         if (offset + bytes <= logical[nr])
5468                                 continue;
5469                         if (logical[nr] == offset) {
5470                                 if (stripe_len >= bytes) {
5471                                         free(logical);
5472                                         return 0;
5473                                 }
5474                                 bytes -= stripe_len;
5475                                 offset += stripe_len;
5476                         } else if (logical[nr] < offset) {
5477                                 if (logical[nr] + stripe_len >=
5478                                     offset + bytes) {
5479                                         free(logical);
5480                                         return 0;
5481                                 }
5482                                 bytes = (offset + bytes) -
5483                                         (logical[nr] + stripe_len);
5484                                 offset = logical[nr] + stripe_len;
5485                         } else {
5486                                 /*
5487                                  * Could be tricky, the super may land in the
5488                                  * middle of the area we're checking.  First
5489                                  * check the easiest case, it's at the end.
5490                                  */
5491                                 if (logical[nr] + stripe_len >=
5492                                     bytes + offset) {
5493                                         bytes = logical[nr] - offset;
5494                                         continue;
5495                                 }
5496
5497                                 /* Check the left side */
5498                                 ret = check_cache_range(root, cache,
5499                                                         offset,
5500                                                         logical[nr] - offset);
5501                                 if (ret) {
5502                                         free(logical);
5503                                         return ret;
5504                                 }
5505
5506                                 /* Now we continue with the right side */
5507                                 bytes = (offset + bytes) -
5508                                         (logical[nr] + stripe_len);
5509                                 offset = logical[nr] + stripe_len;
5510                         }
5511                 }
5512
5513                 free(logical);
5514         }
5515
5516         entry = btrfs_find_free_space(cache->free_space_ctl, offset, bytes);
5517         if (!entry) {
5518                 fprintf(stderr, "There is no free space entry for %Lu-%Lu\n",
5519                         offset, offset+bytes);
5520                 return -EINVAL;
5521         }
5522
5523         if (entry->offset != offset) {
5524                 fprintf(stderr, "Wanted offset %Lu, found %Lu\n", offset,
5525                         entry->offset);
5526                 return -EINVAL;
5527         }
5528
5529         if (entry->bytes != bytes) {
5530                 fprintf(stderr, "Wanted bytes %Lu, found %Lu for off %Lu\n",
5531                         bytes, entry->bytes, offset);
5532                 return -EINVAL;
5533         }
5534
5535         unlink_free_space(cache->free_space_ctl, entry);
5536         free(entry);
5537         return 0;
5538 }
5539
5540 static int verify_space_cache(struct btrfs_root *root,
5541                               struct btrfs_block_group_cache *cache)
5542 {
5543         struct btrfs_path path;
5544         struct extent_buffer *leaf;
5545         struct btrfs_key key;
5546         u64 last;
5547         int ret = 0;
5548
5549         root = root->fs_info->extent_root;
5550
5551         last = max_t(u64, cache->key.objectid, BTRFS_SUPER_INFO_OFFSET);
5552
5553         btrfs_init_path(&path);
5554         key.objectid = last;
5555         key.offset = 0;
5556         key.type = BTRFS_EXTENT_ITEM_KEY;
5557         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
5558         if (ret < 0)
5559                 goto out;
5560         ret = 0;
5561         while (1) {
5562                 if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
5563                         ret = btrfs_next_leaf(root, &path);
5564                         if (ret < 0)
5565                                 goto out;
5566                         if (ret > 0) {
5567                                 ret = 0;
5568                                 break;
5569                         }
5570                 }
5571                 leaf = path.nodes[0];
5572                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
5573                 if (key.objectid >= cache->key.offset + cache->key.objectid)
5574                         break;
5575                 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
5576                     key.type != BTRFS_METADATA_ITEM_KEY) {
5577                         path.slots[0]++;
5578                         continue;
5579                 }
5580
5581                 if (last == key.objectid) {
5582                         if (key.type == BTRFS_EXTENT_ITEM_KEY)
5583                                 last = key.objectid + key.offset;
5584                         else
5585                                 last = key.objectid + root->nodesize;
5586                         path.slots[0]++;
5587                         continue;
5588                 }
5589
5590                 ret = check_cache_range(root, cache, last,
5591                                         key.objectid - last);
5592                 if (ret)
5593                         break;
5594                 if (key.type == BTRFS_EXTENT_ITEM_KEY)
5595                         last = key.objectid + key.offset;
5596                 else
5597                         last = key.objectid + root->nodesize;
5598                 path.slots[0]++;
5599         }
5600
5601         if (last < cache->key.objectid + cache->key.offset)
5602                 ret = check_cache_range(root, cache, last,
5603                                         cache->key.objectid +
5604                                         cache->key.offset - last);
5605
5606 out:
5607         btrfs_release_path(&path);
5608
5609         if (!ret &&
5610             !RB_EMPTY_ROOT(&cache->free_space_ctl->free_space_offset)) {
5611                 fprintf(stderr, "There are still entries left in the space "
5612                         "cache\n");
5613                 ret = -EINVAL;
5614         }
5615
5616         return ret;
5617 }
5618
5619 static int check_space_cache(struct btrfs_root *root)
5620 {
5621         struct btrfs_block_group_cache *cache;
5622         u64 start = BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE;
5623         int ret;
5624         int error = 0;
5625
5626         if (btrfs_super_cache_generation(root->fs_info->super_copy) != -1ULL &&
5627             btrfs_super_generation(root->fs_info->super_copy) !=
5628             btrfs_super_cache_generation(root->fs_info->super_copy)) {
5629                 printf("cache and super generation don't match, space cache "
5630                        "will be invalidated\n");
5631                 return 0;
5632         }
5633
5634         if (ctx.progress_enabled) {
5635                 ctx.tp = TASK_FREE_SPACE;
5636                 task_start(ctx.info);
5637         }
5638
5639         while (1) {
5640                 cache = btrfs_lookup_first_block_group(root->fs_info, start);
5641                 if (!cache)
5642                         break;
5643
5644                 start = cache->key.objectid + cache->key.offset;
5645                 if (!cache->free_space_ctl) {
5646                         if (btrfs_init_free_space_ctl(cache,
5647                                                       root->sectorsize)) {
5648                                 ret = -ENOMEM;
5649                                 break;
5650                         }
5651                 } else {
5652                         btrfs_remove_free_space_cache(cache);
5653                 }
5654
5655                 if (btrfs_fs_compat_ro(root->fs_info,
5656                                        BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
5657                         ret = exclude_super_stripes(root, cache);
5658                         if (ret) {
5659                                 fprintf(stderr, "could not exclude super stripes: %s\n",
5660                                         strerror(-ret));
5661                                 error++;
5662                                 continue;
5663                         }
5664                         ret = load_free_space_tree(root->fs_info, cache);
5665                         free_excluded_extents(root, cache);
5666                         if (ret < 0) {
5667                                 fprintf(stderr, "could not load free space tree: %s\n",
5668                                         strerror(-ret));
5669                                 error++;
5670                                 continue;
5671                         }
5672                         error += ret;
5673                 } else {
5674                         ret = load_free_space_cache(root->fs_info, cache);
5675                         if (!ret)
5676                                 continue;
5677                 }
5678
5679                 ret = verify_space_cache(root, cache);
5680                 if (ret) {
5681                         fprintf(stderr, "cache appears valid but isn't %Lu\n",
5682                                 cache->key.objectid);
5683                         error++;
5684                 }
5685         }
5686
5687         task_stop(ctx.info);
5688
5689         return error ? -EINVAL : 0;
5690 }
5691
5692 static int check_extent_csums(struct btrfs_root *root, u64 bytenr,
5693                         u64 num_bytes, unsigned long leaf_offset,
5694                         struct extent_buffer *eb) {
5695
5696         u64 offset = 0;
5697         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
5698         char *data;
5699         unsigned long csum_offset;
5700         u32 csum;
5701         u32 csum_expected;
5702         u64 read_len;
5703         u64 data_checked = 0;
5704         u64 tmp;
5705         int ret = 0;
5706         int mirror;
5707         int num_copies;
5708
5709         if (num_bytes % root->sectorsize)
5710                 return -EINVAL;
5711
5712         data = malloc(num_bytes);
5713         if (!data)
5714                 return -ENOMEM;
5715
5716         while (offset < num_bytes) {
5717                 mirror = 0;
5718 again:
5719                 read_len = num_bytes - offset;
5720                 /* read as much space once a time */
5721                 ret = read_extent_data(root, data + offset,
5722                                 bytenr + offset, &read_len, mirror);
5723                 if (ret)
5724                         goto out;
5725                 data_checked = 0;
5726                 /* verify every 4k data's checksum */
5727                 while (data_checked < read_len) {
5728                         csum = ~(u32)0;
5729                         tmp = offset + data_checked;
5730
5731                         csum = btrfs_csum_data(NULL, (char *)data + tmp,
5732                                                csum, root->sectorsize);
5733                         btrfs_csum_final(csum, (u8 *)&csum);
5734
5735                         csum_offset = leaf_offset +
5736                                  tmp / root->sectorsize * csum_size;
5737                         read_extent_buffer(eb, (char *)&csum_expected,
5738                                            csum_offset, csum_size);
5739                         /* try another mirror */
5740                         if (csum != csum_expected) {
5741                                 fprintf(stderr, "mirror %d bytenr %llu csum %u expected csum %u\n",
5742                                                 mirror, bytenr + tmp,
5743                                                 csum, csum_expected);
5744                                 num_copies = btrfs_num_copies(
5745                                                 &root->fs_info->mapping_tree,
5746                                                 bytenr, num_bytes);
5747                                 if (mirror < num_copies - 1) {
5748                                         mirror += 1;
5749                                         goto again;
5750                                 }
5751                         }
5752                         data_checked += root->sectorsize;
5753                 }
5754                 offset += read_len;
5755         }
5756 out:
5757         free(data);
5758         return ret;
5759 }
5760
5761 static int check_extent_exists(struct btrfs_root *root, u64 bytenr,
5762                                u64 num_bytes)
5763 {
5764         struct btrfs_path path;
5765         struct extent_buffer *leaf;
5766         struct btrfs_key key;
5767         int ret;
5768
5769         btrfs_init_path(&path);
5770         key.objectid = bytenr;
5771         key.type = BTRFS_EXTENT_ITEM_KEY;
5772         key.offset = (u64)-1;
5773
5774 again:
5775         ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, &path,
5776                                 0, 0);
5777         if (ret < 0) {
5778                 fprintf(stderr, "Error looking up extent record %d\n", ret);
5779                 btrfs_release_path(&path);
5780                 return ret;
5781         } else if (ret) {
5782                 if (path.slots[0] > 0) {
5783                         path.slots[0]--;
5784                 } else {
5785                         ret = btrfs_prev_leaf(root, &path);
5786                         if (ret < 0) {
5787                                 goto out;
5788                         } else if (ret > 0) {
5789                                 ret = 0;
5790                                 goto out;
5791                         }
5792                 }
5793         }
5794
5795         btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
5796
5797         /*
5798          * Block group items come before extent items if they have the same
5799          * bytenr, so walk back one more just in case.  Dear future traveller,
5800          * first congrats on mastering time travel.  Now if it's not too much
5801          * trouble could you go back to 2006 and tell Chris to make the
5802          * BLOCK_GROUP_ITEM_KEY (and BTRFS_*_REF_KEY) lower than the
5803          * EXTENT_ITEM_KEY please?
5804          */
5805         while (key.type > BTRFS_EXTENT_ITEM_KEY) {
5806                 if (path.slots[0] > 0) {
5807                         path.slots[0]--;
5808                 } else {
5809                         ret = btrfs_prev_leaf(root, &path);
5810                         if (ret < 0) {
5811                                 goto out;
5812                         } else if (ret > 0) {
5813                                 ret = 0;
5814                                 goto out;
5815                         }
5816                 }
5817                 btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
5818         }
5819
5820         while (num_bytes) {
5821                 if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
5822                         ret = btrfs_next_leaf(root, &path);
5823                         if (ret < 0) {
5824                                 fprintf(stderr, "Error going to next leaf "
5825                                         "%d\n", ret);
5826                                 btrfs_release_path(&path);
5827                                 return ret;
5828                         } else if (ret) {
5829                                 break;
5830                         }
5831                 }
5832                 leaf = path.nodes[0];
5833                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
5834                 if (key.type != BTRFS_EXTENT_ITEM_KEY) {
5835                         path.slots[0]++;
5836                         continue;
5837                 }
5838                 if (key.objectid + key.offset < bytenr) {
5839                         path.slots[0]++;
5840                         continue;
5841                 }
5842                 if (key.objectid > bytenr + num_bytes)
5843                         break;
5844
5845                 if (key.objectid == bytenr) {
5846                         if (key.offset >= num_bytes) {
5847                                 num_bytes = 0;
5848                                 break;
5849                         }
5850                         num_bytes -= key.offset;
5851                         bytenr += key.offset;
5852                 } else if (key.objectid < bytenr) {
5853                         if (key.objectid + key.offset >= bytenr + num_bytes) {
5854                                 num_bytes = 0;
5855                                 break;
5856                         }
5857                         num_bytes = (bytenr + num_bytes) -
5858                                 (key.objectid + key.offset);
5859                         bytenr = key.objectid + key.offset;
5860                 } else {
5861                         if (key.objectid + key.offset < bytenr + num_bytes) {
5862                                 u64 new_start = key.objectid + key.offset;
5863                                 u64 new_bytes = bytenr + num_bytes - new_start;
5864
5865                                 /*
5866                                  * Weird case, the extent is in the middle of
5867                                  * our range, we'll have to search one side
5868                                  * and then the other.  Not sure if this happens
5869                                  * in real life, but no harm in coding it up
5870                                  * anyway just in case.
5871                                  */
5872                                 btrfs_release_path(&path);
5873                                 ret = check_extent_exists(root, new_start,
5874                                                           new_bytes);
5875                                 if (ret) {
5876                                         fprintf(stderr, "Right section didn't "
5877                                                 "have a record\n");
5878                                         break;
5879                                 }
5880                                 num_bytes = key.objectid - bytenr;
5881                                 goto again;
5882                         }
5883                         num_bytes = key.objectid - bytenr;
5884                 }
5885                 path.slots[0]++;
5886         }
5887         ret = 0;
5888
5889 out:
5890         if (num_bytes && !ret) {
5891                 fprintf(stderr, "There are no extents for csum range "
5892                         "%Lu-%Lu\n", bytenr, bytenr+num_bytes);
5893                 ret = 1;
5894         }
5895
5896         btrfs_release_path(&path);
5897         return ret;
5898 }
5899
5900 static int check_csums(struct btrfs_root *root)
5901 {
5902         struct btrfs_path path;
5903         struct extent_buffer *leaf;
5904         struct btrfs_key key;
5905         u64 offset = 0, num_bytes = 0;
5906         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
5907         int errors = 0;
5908         int ret;
5909         u64 data_len;
5910         unsigned long leaf_offset;
5911
5912         root = root->fs_info->csum_root;
5913         if (!extent_buffer_uptodate(root->node)) {
5914                 fprintf(stderr, "No valid csum tree found\n");
5915                 return -ENOENT;
5916         }
5917
5918         btrfs_init_path(&path);
5919         key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
5920         key.type = BTRFS_EXTENT_CSUM_KEY;
5921         key.offset = 0;
5922         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
5923         if (ret < 0) {
5924                 fprintf(stderr, "Error searching csum tree %d\n", ret);
5925                 btrfs_release_path(&path);
5926                 return ret;
5927         }
5928
5929         if (ret > 0 && path.slots[0])
5930                 path.slots[0]--;
5931         ret = 0;
5932
5933         while (1) {
5934                 if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
5935                         ret = btrfs_next_leaf(root, &path);
5936                         if (ret < 0) {
5937                                 fprintf(stderr, "Error going to next leaf "
5938                                         "%d\n", ret);
5939                                 break;
5940                         }
5941                         if (ret)
5942                                 break;
5943                 }
5944                 leaf = path.nodes[0];
5945
5946                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
5947                 if (key.type != BTRFS_EXTENT_CSUM_KEY) {
5948                         path.slots[0]++;
5949                         continue;
5950                 }
5951
5952                 data_len = (btrfs_item_size_nr(leaf, path.slots[0]) /
5953                               csum_size) * root->sectorsize;
5954                 if (!check_data_csum)
5955                         goto skip_csum_check;
5956                 leaf_offset = btrfs_item_ptr_offset(leaf, path.slots[0]);
5957                 ret = check_extent_csums(root, key.offset, data_len,
5958                                          leaf_offset, leaf);
5959                 if (ret)
5960                         break;
5961 skip_csum_check:
5962                 if (!num_bytes) {
5963                         offset = key.offset;
5964                 } else if (key.offset != offset + num_bytes) {
5965                         ret = check_extent_exists(root, offset, num_bytes);
5966                         if (ret) {
5967                                 fprintf(stderr, "Csum exists for %Lu-%Lu but "
5968                                         "there is no extent record\n",
5969                                         offset, offset+num_bytes);
5970                                 errors++;
5971                         }
5972                         offset = key.offset;
5973                         num_bytes = 0;
5974                 }
5975                 num_bytes += data_len;
5976                 path.slots[0]++;
5977         }
5978
5979         btrfs_release_path(&path);
5980         return errors;
5981 }
5982
5983 static int is_dropped_key(struct btrfs_key *key,
5984                           struct btrfs_key *drop_key) {
5985         if (key->objectid < drop_key->objectid)
5986                 return 1;
5987         else if (key->objectid == drop_key->objectid) {
5988                 if (key->type < drop_key->type)
5989                         return 1;
5990                 else if (key->type == drop_key->type) {
5991                         if (key->offset < drop_key->offset)
5992                                 return 1;
5993                 }
5994         }
5995         return 0;
5996 }
5997
5998 /*
5999  * Here are the rules for FULL_BACKREF.
6000  *
6001  * 1) If BTRFS_HEADER_FLAG_RELOC is set then we have FULL_BACKREF set.
6002  * 2) If btrfs_header_owner(buf) no longer points to buf then we have
6003  *      FULL_BACKREF set.
6004  * 3) We cowed the block walking down a reloc tree.  This is impossible to tell
6005  *    if it happened after the relocation occurred since we'll have dropped the
6006  *    reloc root, so it's entirely possible to have FULL_BACKREF set on buf and
6007  *    have no real way to know for sure.
6008  *
6009  * We process the blocks one root at a time, and we start from the lowest root
6010  * objectid and go to the highest.  So we can just lookup the owner backref for
6011  * the record and if we don't find it then we know it doesn't exist and we have
6012  * a FULL BACKREF.
6013  *
6014  * FIXME: if we ever start reclaiming root objectid's then we need to fix this
6015  * assumption and simply indicate that we _think_ that the FULL BACKREF needs to
6016  * be set or not and then we can check later once we've gathered all the refs.
6017  */
6018 static int calc_extent_flag(struct btrfs_root *root,
6019                            struct cache_tree *extent_cache,
6020                            struct extent_buffer *buf,
6021                            struct root_item_record *ri,
6022                            u64 *flags)
6023 {
6024         struct extent_record *rec;
6025         struct cache_extent *cache;
6026         struct tree_backref *tback;
6027         u64 owner = 0;
6028
6029         cache = lookup_cache_extent(extent_cache, buf->start, 1);
6030         /* we have added this extent before */
6031         if (!cache)
6032                 return -ENOENT;
6033
6034         rec = container_of(cache, struct extent_record, cache);
6035
6036         /*
6037          * Except file/reloc tree, we can not have
6038          * FULL BACKREF MODE
6039          */
6040         if (ri->objectid < BTRFS_FIRST_FREE_OBJECTID)
6041                 goto normal;
6042         /*
6043          * root node
6044          */
6045         if (buf->start == ri->bytenr)
6046                 goto normal;
6047
6048         if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))
6049                 goto full_backref;
6050
6051         owner = btrfs_header_owner(buf);
6052         if (owner == ri->objectid)
6053                 goto normal;
6054
6055         tback = find_tree_backref(rec, 0, owner);
6056         if (!tback)
6057                 goto full_backref;
6058 normal:
6059         *flags = 0;
6060         if (rec->flag_block_full_backref != FLAG_UNSET &&
6061             rec->flag_block_full_backref != 0)
6062                 rec->bad_full_backref = 1;
6063         return 0;
6064 full_backref:
6065         *flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
6066         if (rec->flag_block_full_backref != FLAG_UNSET &&
6067             rec->flag_block_full_backref != 1)
6068                 rec->bad_full_backref = 1;
6069         return 0;
6070 }
6071
6072 static void report_mismatch_key_root(u8 key_type, u64 rootid)
6073 {
6074         fprintf(stderr, "Invalid key type(");
6075         print_key_type(stderr, 0, key_type);
6076         fprintf(stderr, ") found in root(");
6077         print_objectid(stderr, rootid, 0);
6078         fprintf(stderr, ")\n");
6079 }
6080
6081 /*
6082  * Check if the key is valid with its extent buffer.
6083  *
6084  * This is a early check in case invalid key exists in a extent buffer
6085  * This is not comprehensive yet, but should prevent wrong key/item passed
6086  * further
6087  */
6088 static int check_type_with_root(u64 rootid, u8 key_type)
6089 {
6090         switch (key_type) {
6091         /* Only valid in chunk tree */
6092         case BTRFS_DEV_ITEM_KEY:
6093         case BTRFS_CHUNK_ITEM_KEY:
6094                 if (rootid != BTRFS_CHUNK_TREE_OBJECTID)
6095                         goto err;
6096                 break;
6097         /* valid in csum and log tree */
6098         case BTRFS_CSUM_TREE_OBJECTID:
6099                 if (!(rootid == BTRFS_TREE_LOG_OBJECTID ||
6100                       is_fstree(rootid)))
6101                         goto err;
6102                 break;
6103         case BTRFS_EXTENT_ITEM_KEY:
6104         case BTRFS_METADATA_ITEM_KEY:
6105         case BTRFS_BLOCK_GROUP_ITEM_KEY:
6106                 if (rootid != BTRFS_EXTENT_TREE_OBJECTID)
6107                         goto err;
6108                 break;
6109         case BTRFS_ROOT_ITEM_KEY:
6110                 if (rootid != BTRFS_ROOT_TREE_OBJECTID)
6111                         goto err;
6112                 break;
6113         case BTRFS_DEV_EXTENT_KEY:
6114                 if (rootid != BTRFS_DEV_TREE_OBJECTID)
6115                         goto err;
6116                 break;
6117         }
6118         return 0;
6119 err:
6120         report_mismatch_key_root(key_type, rootid);
6121         return -EINVAL;
6122 }
6123
6124 static int run_next_block(struct btrfs_root *root,
6125                           struct block_info *bits,
6126                           int bits_nr,
6127                           u64 *last,
6128                           struct cache_tree *pending,
6129                           struct cache_tree *seen,
6130                           struct cache_tree *reada,
6131                           struct cache_tree *nodes,
6132                           struct cache_tree *extent_cache,
6133                           struct cache_tree *chunk_cache,
6134                           struct rb_root *dev_cache,
6135                           struct block_group_tree *block_group_cache,
6136                           struct device_extent_tree *dev_extent_cache,
6137                           struct root_item_record *ri)
6138 {
6139         struct extent_buffer *buf;
6140         struct extent_record *rec = NULL;
6141         u64 bytenr;
6142         u32 size;
6143         u64 parent;
6144         u64 owner;
6145         u64 flags;
6146         u64 ptr;
6147         u64 gen = 0;
6148         int ret = 0;
6149         int i;
6150         int nritems;
6151         struct btrfs_key key;
6152         struct cache_extent *cache;
6153         int reada_bits;
6154
6155         nritems = pick_next_pending(pending, reada, nodes, *last, bits,
6156                                     bits_nr, &reada_bits);
6157         if (nritems == 0)
6158                 return 1;
6159
6160         if (!reada_bits) {
6161                 for(i = 0; i < nritems; i++) {
6162                         ret = add_cache_extent(reada, bits[i].start,
6163                                                bits[i].size);
6164                         if (ret == -EEXIST)
6165                                 continue;
6166
6167                         /* fixme, get the parent transid */
6168                         readahead_tree_block(root, bits[i].start,
6169                                              bits[i].size, 0);
6170                 }
6171         }
6172         *last = bits[0].start;
6173         bytenr = bits[0].start;
6174         size = bits[0].size;
6175
6176         cache = lookup_cache_extent(pending, bytenr, size);
6177         if (cache) {
6178                 remove_cache_extent(pending, cache);
6179                 free(cache);
6180         }
6181         cache = lookup_cache_extent(reada, bytenr, size);
6182         if (cache) {
6183                 remove_cache_extent(reada, cache);
6184                 free(cache);
6185         }
6186         cache = lookup_cache_extent(nodes, bytenr, size);
6187         if (cache) {
6188                 remove_cache_extent(nodes, cache);
6189                 free(cache);
6190         }
6191         cache = lookup_cache_extent(extent_cache, bytenr, size);
6192         if (cache) {
6193                 rec = container_of(cache, struct extent_record, cache);
6194                 gen = rec->parent_generation;
6195         }
6196
6197         /* fixme, get the real parent transid */
6198         buf = read_tree_block(root, bytenr, size, gen);
6199         if (!extent_buffer_uptodate(buf)) {
6200                 record_bad_block_io(root->fs_info,
6201                                     extent_cache, bytenr, size);
6202                 goto out;
6203         }
6204
6205         nritems = btrfs_header_nritems(buf);
6206
6207         flags = 0;
6208         if (!init_extent_tree) {
6209                 ret = btrfs_lookup_extent_info(NULL, root, bytenr,
6210                                        btrfs_header_level(buf), 1, NULL,
6211                                        &flags);
6212                 if (ret < 0) {
6213                         ret = calc_extent_flag(root, extent_cache, buf, ri, &flags);
6214                         if (ret < 0) {
6215                                 fprintf(stderr, "Couldn't calc extent flags\n");
6216                                 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
6217                         }
6218                 }
6219         } else {
6220                 flags = 0;
6221                 ret = calc_extent_flag(root, extent_cache, buf, ri, &flags);
6222                 if (ret < 0) {
6223                         fprintf(stderr, "Couldn't calc extent flags\n");
6224                         flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
6225                 }
6226         }
6227
6228         if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6229                 if (ri != NULL &&
6230                     ri->objectid != BTRFS_TREE_RELOC_OBJECTID &&
6231                     ri->objectid == btrfs_header_owner(buf)) {
6232                         /*
6233                          * Ok we got to this block from it's original owner and
6234                          * we have FULL_BACKREF set.  Relocation can leave
6235                          * converted blocks over so this is altogether possible,
6236                          * however it's not possible if the generation > the
6237                          * last snapshot, so check for this case.
6238                          */
6239                         if (!btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC) &&
6240                             btrfs_header_generation(buf) > ri->last_snapshot) {
6241                                 flags &= ~BTRFS_BLOCK_FLAG_FULL_BACKREF;
6242                                 rec->bad_full_backref = 1;
6243                         }
6244                 }
6245         } else {
6246                 if (ri != NULL &&
6247                     (ri->objectid == BTRFS_TREE_RELOC_OBJECTID ||
6248                      btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))) {
6249                         flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
6250                         rec->bad_full_backref = 1;
6251                 }
6252         }
6253
6254         if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6255                 rec->flag_block_full_backref = 1;
6256                 parent = bytenr;
6257                 owner = 0;
6258         } else {
6259                 rec->flag_block_full_backref = 0;
6260                 parent = 0;
6261                 owner = btrfs_header_owner(buf);
6262         }
6263
6264         ret = check_block(root, extent_cache, buf, flags);
6265         if (ret)
6266                 goto out;
6267
6268         if (btrfs_is_leaf(buf)) {
6269                 btree_space_waste += btrfs_leaf_free_space(root, buf);
6270                 for (i = 0; i < nritems; i++) {
6271                         struct btrfs_file_extent_item *fi;
6272                         btrfs_item_key_to_cpu(buf, &key, i);
6273                         /*
6274                          * Check key type against the leaf owner.
6275                          * Could filter quite a lot of early error if
6276                          * owner is correct
6277                          */
6278                         if (check_type_with_root(btrfs_header_owner(buf),
6279                                                  key.type)) {
6280                                 fprintf(stderr, "ignoring invalid key\n");
6281                                 continue;
6282                         }
6283                         if (key.type == BTRFS_EXTENT_ITEM_KEY) {
6284                                 process_extent_item(root, extent_cache, buf,
6285                                                     i);
6286                                 continue;
6287                         }
6288                         if (key.type == BTRFS_METADATA_ITEM_KEY) {
6289                                 process_extent_item(root, extent_cache, buf,
6290                                                     i);
6291                                 continue;
6292                         }
6293                         if (key.type == BTRFS_EXTENT_CSUM_KEY) {
6294                                 total_csum_bytes +=
6295                                         btrfs_item_size_nr(buf, i);
6296                                 continue;
6297                         }
6298                         if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6299                                 process_chunk_item(chunk_cache, &key, buf, i);
6300                                 continue;
6301                         }
6302                         if (key.type == BTRFS_DEV_ITEM_KEY) {
6303                                 process_device_item(dev_cache, &key, buf, i);
6304                                 continue;
6305                         }
6306                         if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
6307                                 process_block_group_item(block_group_cache,
6308                                         &key, buf, i);
6309                                 continue;
6310                         }
6311                         if (key.type == BTRFS_DEV_EXTENT_KEY) {
6312                                 process_device_extent_item(dev_extent_cache,
6313                                         &key, buf, i);
6314                                 continue;
6315
6316                         }
6317                         if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
6318 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
6319                                 process_extent_ref_v0(extent_cache, buf, i);
6320 #else
6321                                 BUG();
6322 #endif
6323                                 continue;
6324                         }
6325
6326                         if (key.type == BTRFS_TREE_BLOCK_REF_KEY) {
6327                                 ret = add_tree_backref(extent_cache,
6328                                                 key.objectid, 0, key.offset, 0);
6329                                 if (ret < 0)
6330                                         error("add_tree_backref failed: %s",
6331                                               strerror(-ret));
6332                                 continue;
6333                         }
6334                         if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) {
6335                                 ret = add_tree_backref(extent_cache,
6336                                                 key.objectid, key.offset, 0, 0);
6337                                 if (ret < 0)
6338                                         error("add_tree_backref failed: %s",
6339                                               strerror(-ret));
6340                                 continue;
6341                         }
6342                         if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
6343                                 struct btrfs_extent_data_ref *ref;
6344                                 ref = btrfs_item_ptr(buf, i,
6345                                                 struct btrfs_extent_data_ref);
6346                                 add_data_backref(extent_cache,
6347                                         key.objectid, 0,
6348                                         btrfs_extent_data_ref_root(buf, ref),
6349                                         btrfs_extent_data_ref_objectid(buf,
6350                                                                        ref),
6351                                         btrfs_extent_data_ref_offset(buf, ref),
6352                                         btrfs_extent_data_ref_count(buf, ref),
6353                                         0, root->sectorsize);
6354                                 continue;
6355                         }
6356                         if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
6357                                 struct btrfs_shared_data_ref *ref;
6358                                 ref = btrfs_item_ptr(buf, i,
6359                                                 struct btrfs_shared_data_ref);
6360                                 add_data_backref(extent_cache,
6361                                         key.objectid, key.offset, 0, 0, 0,
6362                                         btrfs_shared_data_ref_count(buf, ref),
6363                                         0, root->sectorsize);
6364                                 continue;
6365                         }
6366                         if (key.type == BTRFS_ORPHAN_ITEM_KEY) {
6367                                 struct bad_item *bad;
6368
6369                                 if (key.objectid == BTRFS_ORPHAN_OBJECTID)
6370                                         continue;
6371                                 if (!owner)
6372                                         continue;
6373                                 bad = malloc(sizeof(struct bad_item));
6374                                 if (!bad)
6375                                         continue;
6376                                 INIT_LIST_HEAD(&bad->list);
6377                                 memcpy(&bad->key, &key,
6378                                        sizeof(struct btrfs_key));
6379                                 bad->root_id = owner;
6380                                 list_add_tail(&bad->list, &delete_items);
6381                                 continue;
6382                         }
6383                         if (key.type != BTRFS_EXTENT_DATA_KEY)
6384                                 continue;
6385                         fi = btrfs_item_ptr(buf, i,
6386                                             struct btrfs_file_extent_item);
6387                         if (btrfs_file_extent_type(buf, fi) ==
6388                             BTRFS_FILE_EXTENT_INLINE)
6389                                 continue;
6390                         if (btrfs_file_extent_disk_bytenr(buf, fi) == 0)
6391                                 continue;
6392
6393                         data_bytes_allocated +=
6394                                 btrfs_file_extent_disk_num_bytes(buf, fi);
6395                         if (data_bytes_allocated < root->sectorsize) {
6396                                 abort();
6397                         }
6398                         data_bytes_referenced +=
6399                                 btrfs_file_extent_num_bytes(buf, fi);
6400                         add_data_backref(extent_cache,
6401                                 btrfs_file_extent_disk_bytenr(buf, fi),
6402                                 parent, owner, key.objectid, key.offset -
6403                                 btrfs_file_extent_offset(buf, fi), 1, 1,
6404                                 btrfs_file_extent_disk_num_bytes(buf, fi));
6405                 }
6406         } else {
6407                 int level;
6408                 struct btrfs_key first_key;
6409
6410                 first_key.objectid = 0;
6411
6412                 if (nritems > 0)
6413                         btrfs_item_key_to_cpu(buf, &first_key, 0);
6414                 level = btrfs_header_level(buf);
6415                 for (i = 0; i < nritems; i++) {
6416                         struct extent_record tmpl;
6417
6418                         ptr = btrfs_node_blockptr(buf, i);
6419                         size = root->nodesize;
6420                         btrfs_node_key_to_cpu(buf, &key, i);
6421                         if (ri != NULL) {
6422                                 if ((level == ri->drop_level)
6423                                     && is_dropped_key(&key, &ri->drop_key)) {
6424                                         continue;
6425                                 }
6426                         }
6427
6428                         memset(&tmpl, 0, sizeof(tmpl));
6429                         btrfs_cpu_key_to_disk(&tmpl.parent_key, &key);
6430                         tmpl.parent_generation = btrfs_node_ptr_generation(buf, i);
6431                         tmpl.start = ptr;
6432                         tmpl.nr = size;
6433                         tmpl.refs = 1;
6434                         tmpl.metadata = 1;
6435                         tmpl.max_size = size;
6436                         ret = add_extent_rec(extent_cache, &tmpl);
6437                         if (ret < 0)
6438                                 goto out;
6439
6440                         ret = add_tree_backref(extent_cache, ptr, parent,
6441                                         owner, 1);
6442                         if (ret < 0) {
6443                                 error("add_tree_backref failed: %s",
6444                                       strerror(-ret));
6445                                 continue;
6446                         }
6447
6448                         if (level > 1) {
6449                                 add_pending(nodes, seen, ptr, size);
6450                         } else {
6451                                 add_pending(pending, seen, ptr, size);
6452                         }
6453                 }
6454                 btree_space_waste += (BTRFS_NODEPTRS_PER_BLOCK(root) -
6455                                       nritems) * sizeof(struct btrfs_key_ptr);
6456         }
6457         total_btree_bytes += buf->len;
6458         if (fs_root_objectid(btrfs_header_owner(buf)))
6459                 total_fs_tree_bytes += buf->len;
6460         if (btrfs_header_owner(buf) == BTRFS_EXTENT_TREE_OBJECTID)
6461                 total_extent_tree_bytes += buf->len;
6462         if (!found_old_backref &&
6463             btrfs_header_owner(buf) == BTRFS_TREE_RELOC_OBJECTID &&
6464             btrfs_header_backref_rev(buf) == BTRFS_MIXED_BACKREF_REV &&
6465             !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))
6466                 found_old_backref = 1;
6467 out:
6468         free_extent_buffer(buf);
6469         return ret;
6470 }
6471
6472 static int add_root_to_pending(struct extent_buffer *buf,
6473                                struct cache_tree *extent_cache,
6474                                struct cache_tree *pending,
6475                                struct cache_tree *seen,
6476                                struct cache_tree *nodes,
6477                                u64 objectid)
6478 {
6479         struct extent_record tmpl;
6480         int ret;
6481
6482         if (btrfs_header_level(buf) > 0)
6483                 add_pending(nodes, seen, buf->start, buf->len);
6484         else
6485                 add_pending(pending, seen, buf->start, buf->len);
6486
6487         memset(&tmpl, 0, sizeof(tmpl));
6488         tmpl.start = buf->start;
6489         tmpl.nr = buf->len;
6490         tmpl.is_root = 1;
6491         tmpl.refs = 1;
6492         tmpl.metadata = 1;
6493         tmpl.max_size = buf->len;
6494         add_extent_rec(extent_cache, &tmpl);
6495
6496         if (objectid == BTRFS_TREE_RELOC_OBJECTID ||
6497             btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV)
6498                 ret = add_tree_backref(extent_cache, buf->start, buf->start,
6499                                 0, 1);
6500         else
6501                 ret = add_tree_backref(extent_cache, buf->start, 0, objectid,
6502                                 1);
6503         return ret;
6504 }
6505
6506 /* as we fix the tree, we might be deleting blocks that
6507  * we're tracking for repair.  This hook makes sure we
6508  * remove any backrefs for blocks as we are fixing them.
6509  */
6510 static int free_extent_hook(struct btrfs_trans_handle *trans,
6511                             struct btrfs_root *root,
6512                             u64 bytenr, u64 num_bytes, u64 parent,
6513                             u64 root_objectid, u64 owner, u64 offset,
6514                             int refs_to_drop)
6515 {
6516         struct extent_record *rec;
6517         struct cache_extent *cache;
6518         int is_data;
6519         struct cache_tree *extent_cache = root->fs_info->fsck_extent_cache;
6520
6521         is_data = owner >= BTRFS_FIRST_FREE_OBJECTID;
6522         cache = lookup_cache_extent(extent_cache, bytenr, num_bytes);
6523         if (!cache)
6524                 return 0;
6525
6526         rec = container_of(cache, struct extent_record, cache);
6527         if (is_data) {
6528                 struct data_backref *back;
6529                 back = find_data_backref(rec, parent, root_objectid, owner,
6530                                          offset, 1, bytenr, num_bytes);
6531                 if (!back)
6532                         goto out;
6533                 if (back->node.found_ref) {
6534                         back->found_ref -= refs_to_drop;
6535                         if (rec->refs)
6536                                 rec->refs -= refs_to_drop;
6537                 }
6538                 if (back->node.found_extent_tree) {
6539                         back->num_refs -= refs_to_drop;
6540                         if (rec->extent_item_refs)
6541                                 rec->extent_item_refs -= refs_to_drop;
6542                 }
6543                 if (back->found_ref == 0)
6544                         back->node.found_ref = 0;
6545                 if (back->num_refs == 0)
6546                         back->node.found_extent_tree = 0;
6547
6548                 if (!back->node.found_extent_tree && back->node.found_ref) {
6549                         list_del(&back->node.list);
6550                         free(back);
6551                 }
6552         } else {
6553                 struct tree_backref *back;
6554                 back = find_tree_backref(rec, parent, root_objectid);
6555                 if (!back)
6556                         goto out;
6557                 if (back->node.found_ref) {
6558                         if (rec->refs)
6559                                 rec->refs--;
6560                         back->node.found_ref = 0;
6561                 }
6562                 if (back->node.found_extent_tree) {
6563                         if (rec->extent_item_refs)
6564                                 rec->extent_item_refs--;
6565                         back->node.found_extent_tree = 0;
6566                 }
6567                 if (!back->node.found_extent_tree && back->node.found_ref) {
6568                         list_del(&back->node.list);
6569                         free(back);
6570                 }
6571         }
6572         maybe_free_extent_rec(extent_cache, rec);
6573 out:
6574         return 0;
6575 }
6576
6577 static int delete_extent_records(struct btrfs_trans_handle *trans,
6578                                  struct btrfs_root *root,
6579                                  struct btrfs_path *path,
6580                                  u64 bytenr, u64 new_len)
6581 {
6582         struct btrfs_key key;
6583         struct btrfs_key found_key;
6584         struct extent_buffer *leaf;
6585         int ret;
6586         int slot;
6587
6588
6589         key.objectid = bytenr;
6590         key.type = (u8)-1;
6591         key.offset = (u64)-1;
6592
6593         while(1) {
6594                 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
6595                                         &key, path, 0, 1);
6596                 if (ret < 0)
6597                         break;
6598
6599                 if (ret > 0) {
6600                         ret = 0;
6601                         if (path->slots[0] == 0)
6602                                 break;
6603                         path->slots[0]--;
6604                 }
6605                 ret = 0;
6606
6607                 leaf = path->nodes[0];
6608                 slot = path->slots[0];
6609
6610                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6611                 if (found_key.objectid != bytenr)
6612                         break;
6613
6614                 if (found_key.type != BTRFS_EXTENT_ITEM_KEY &&
6615                     found_key.type != BTRFS_METADATA_ITEM_KEY &&
6616                     found_key.type != BTRFS_TREE_BLOCK_REF_KEY &&
6617                     found_key.type != BTRFS_EXTENT_DATA_REF_KEY &&
6618                     found_key.type != BTRFS_EXTENT_REF_V0_KEY &&
6619                     found_key.type != BTRFS_SHARED_BLOCK_REF_KEY &&
6620                     found_key.type != BTRFS_SHARED_DATA_REF_KEY) {
6621                         btrfs_release_path(path);
6622                         if (found_key.type == 0) {
6623                                 if (found_key.offset == 0)
6624                                         break;
6625                                 key.offset = found_key.offset - 1;
6626                                 key.type = found_key.type;
6627                         }
6628                         key.type = found_key.type - 1;
6629                         key.offset = (u64)-1;
6630                         continue;
6631                 }
6632
6633                 fprintf(stderr, "repair deleting extent record: key %Lu %u %Lu\n",
6634                         found_key.objectid, found_key.type, found_key.offset);
6635
6636                 ret = btrfs_del_item(trans, root->fs_info->extent_root, path);
6637                 if (ret)
6638                         break;
6639                 btrfs_release_path(path);
6640
6641                 if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
6642                     found_key.type == BTRFS_METADATA_ITEM_KEY) {
6643                         u64 bytes = (found_key.type == BTRFS_EXTENT_ITEM_KEY) ?
6644                                 found_key.offset : root->nodesize;
6645
6646                         ret = btrfs_update_block_group(trans, root, bytenr,
6647                                                        bytes, 0, 0);
6648                         if (ret)
6649                                 break;
6650                 }
6651         }
6652
6653         btrfs_release_path(path);
6654         return ret;
6655 }
6656
6657 /*
6658  * for a single backref, this will allocate a new extent
6659  * and add the backref to it.
6660  */
6661 static int record_extent(struct btrfs_trans_handle *trans,
6662                          struct btrfs_fs_info *info,
6663                          struct btrfs_path *path,
6664                          struct extent_record *rec,
6665                          struct extent_backref *back,
6666                          int allocated, u64 flags)
6667 {
6668         int ret;
6669         struct btrfs_root *extent_root = info->extent_root;
6670         struct extent_buffer *leaf;
6671         struct btrfs_key ins_key;
6672         struct btrfs_extent_item *ei;
6673         struct data_backref *dback;
6674         struct btrfs_tree_block_info *bi;
6675
6676         if (!back->is_data)
6677                 rec->max_size = max_t(u64, rec->max_size,
6678                                     info->extent_root->nodesize);
6679
6680         if (!allocated) {
6681                 u32 item_size = sizeof(*ei);
6682
6683                 if (!back->is_data)
6684                         item_size += sizeof(*bi);
6685
6686                 ins_key.objectid = rec->start;
6687                 ins_key.offset = rec->max_size;
6688                 ins_key.type = BTRFS_EXTENT_ITEM_KEY;
6689
6690                 ret = btrfs_insert_empty_item(trans, extent_root, path,
6691                                         &ins_key, item_size);
6692                 if (ret)
6693                         goto fail;
6694
6695                 leaf = path->nodes[0];
6696                 ei = btrfs_item_ptr(leaf, path->slots[0],
6697                                     struct btrfs_extent_item);
6698
6699                 btrfs_set_extent_refs(leaf, ei, 0);
6700                 btrfs_set_extent_generation(leaf, ei, rec->generation);
6701
6702                 if (back->is_data) {
6703                         btrfs_set_extent_flags(leaf, ei,
6704                                                BTRFS_EXTENT_FLAG_DATA);
6705                 } else {
6706                         struct btrfs_disk_key copy_key;;
6707
6708                         bi = (struct btrfs_tree_block_info *)(ei + 1);
6709                         memset_extent_buffer(leaf, 0, (unsigned long)bi,
6710                                              sizeof(*bi));
6711
6712                         btrfs_set_disk_key_objectid(&copy_key,
6713                                                     rec->info_objectid);
6714                         btrfs_set_disk_key_type(&copy_key, 0);
6715                         btrfs_set_disk_key_offset(&copy_key, 0);
6716
6717                         btrfs_set_tree_block_level(leaf, bi, rec->info_level);
6718                         btrfs_set_tree_block_key(leaf, bi, &copy_key);
6719
6720                         btrfs_set_extent_flags(leaf, ei,
6721                                                BTRFS_EXTENT_FLAG_TREE_BLOCK | flags);
6722                 }
6723
6724                 btrfs_mark_buffer_dirty(leaf);
6725                 ret = btrfs_update_block_group(trans, extent_root, rec->start,
6726                                                rec->max_size, 1, 0);
6727                 if (ret)
6728                         goto fail;
6729                 btrfs_release_path(path);
6730         }
6731
6732         if (back->is_data) {
6733                 u64 parent;
6734                 int i;
6735
6736                 dback = to_data_backref(back);
6737                 if (back->full_backref)
6738                         parent = dback->parent;
6739                 else
6740                         parent = 0;
6741
6742                 for (i = 0; i < dback->found_ref; i++) {
6743                         /* if parent != 0, we're doing a full backref
6744                          * passing BTRFS_FIRST_FREE_OBJECTID as the owner
6745                          * just makes the backref allocator create a data
6746                          * backref
6747                          */
6748                         ret = btrfs_inc_extent_ref(trans, info->extent_root,
6749                                                    rec->start, rec->max_size,
6750                                                    parent,
6751                                                    dback->root,
6752                                                    parent ?
6753                                                    BTRFS_FIRST_FREE_OBJECTID :
6754                                                    dback->owner,
6755                                                    dback->offset);
6756                         if (ret)
6757                                 break;
6758                 }
6759                 fprintf(stderr, "adding new data backref"
6760                                 " on %llu %s %llu owner %llu"
6761                                 " offset %llu found %d\n",
6762                                 (unsigned long long)rec->start,
6763                                 back->full_backref ?
6764                                 "parent" : "root",
6765                                 back->full_backref ?
6766                                 (unsigned long long)parent :
6767                                 (unsigned long long)dback->root,
6768                                 (unsigned long long)dback->owner,
6769                                 (unsigned long long)dback->offset,
6770                                 dback->found_ref);
6771         } else {
6772                 u64 parent;
6773                 struct tree_backref *tback;
6774
6775                 tback = to_tree_backref(back);
6776                 if (back->full_backref)
6777                         parent = tback->parent;
6778                 else
6779                         parent = 0;
6780
6781                 ret = btrfs_inc_extent_ref(trans, info->extent_root,
6782                                            rec->start, rec->max_size,
6783                                            parent, tback->root, 0, 0);
6784                 fprintf(stderr, "adding new tree backref on "
6785                         "start %llu len %llu parent %llu root %llu\n",
6786                         rec->start, rec->max_size, parent, tback->root);
6787         }
6788 fail:
6789         btrfs_release_path(path);
6790         return ret;
6791 }
6792
6793 static struct extent_entry *find_entry(struct list_head *entries,
6794                                        u64 bytenr, u64 bytes)
6795 {
6796         struct extent_entry *entry = NULL;
6797
6798         list_for_each_entry(entry, entries, list) {
6799                 if (entry->bytenr == bytenr && entry->bytes == bytes)
6800                         return entry;
6801         }
6802
6803         return NULL;
6804 }
6805
6806 static struct extent_entry *find_most_right_entry(struct list_head *entries)
6807 {
6808         struct extent_entry *entry, *best = NULL, *prev = NULL;
6809
6810         list_for_each_entry(entry, entries, list) {
6811                 /*
6812                  * If there are as many broken entries as entries then we know
6813                  * not to trust this particular entry.
6814                  */
6815                 if (entry->broken == entry->count)
6816                         continue;
6817
6818                 /*
6819                  * Special case, when there are only two entries and 'best' is
6820                  * the first one
6821                  */
6822                 if (!prev) {
6823                         best = entry;
6824                         prev = entry;
6825                         continue;
6826                 }
6827
6828                 /*
6829                  * If our current entry == best then we can't be sure our best
6830                  * is really the best, so we need to keep searching.
6831                  */
6832                 if (best && best->count == entry->count) {
6833                         prev = entry;
6834                         best = NULL;
6835                         continue;
6836                 }
6837
6838                 /* Prev == entry, not good enough, have to keep searching */
6839                 if (!prev->broken && prev->count == entry->count)
6840                         continue;
6841
6842                 if (!best)
6843                         best = (prev->count > entry->count) ? prev : entry;
6844                 else if (best->count < entry->count)
6845                         best = entry;
6846                 prev = entry;
6847         }
6848
6849         return best;
6850 }
6851
6852 static int repair_ref(struct btrfs_fs_info *info, struct btrfs_path *path,
6853                       struct data_backref *dback, struct extent_entry *entry)
6854 {
6855         struct btrfs_trans_handle *trans;
6856         struct btrfs_root *root;
6857         struct btrfs_file_extent_item *fi;
6858         struct extent_buffer *leaf;
6859         struct btrfs_key key;
6860         u64 bytenr, bytes;
6861         int ret, err;
6862
6863         key.objectid = dback->root;
6864         key.type = BTRFS_ROOT_ITEM_KEY;
6865         key.offset = (u64)-1;
6866         root = btrfs_read_fs_root(info, &key);
6867         if (IS_ERR(root)) {
6868                 fprintf(stderr, "Couldn't find root for our ref\n");
6869                 return -EINVAL;
6870         }
6871
6872         /*
6873          * The backref points to the original offset of the extent if it was
6874          * split, so we need to search down to the offset we have and then walk
6875          * forward until we find the backref we're looking for.
6876          */
6877         key.objectid = dback->owner;
6878         key.type = BTRFS_EXTENT_DATA_KEY;
6879         key.offset = dback->offset;
6880         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6881         if (ret < 0) {
6882                 fprintf(stderr, "Error looking up ref %d\n", ret);
6883                 return ret;
6884         }
6885
6886         while (1) {
6887                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
6888                         ret = btrfs_next_leaf(root, path);
6889                         if (ret) {
6890                                 fprintf(stderr, "Couldn't find our ref, next\n");
6891                                 return -EINVAL;
6892                         }
6893                 }
6894                 leaf = path->nodes[0];
6895                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
6896                 if (key.objectid != dback->owner ||
6897                     key.type != BTRFS_EXTENT_DATA_KEY) {
6898                         fprintf(stderr, "Couldn't find our ref, search\n");
6899                         return -EINVAL;
6900                 }
6901                 fi = btrfs_item_ptr(leaf, path->slots[0],
6902                                     struct btrfs_file_extent_item);
6903                 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6904                 bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
6905
6906                 if (bytenr == dback->disk_bytenr && bytes == dback->bytes)
6907                         break;
6908                 path->slots[0]++;
6909         }
6910
6911         btrfs_release_path(path);
6912
6913         trans = btrfs_start_transaction(root, 1);
6914         if (IS_ERR(trans))
6915                 return PTR_ERR(trans);
6916
6917         /*
6918          * Ok we have the key of the file extent we want to fix, now we can cow
6919          * down to the thing and fix it.
6920          */
6921         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
6922         if (ret < 0) {
6923                 fprintf(stderr, "Error cowing down to ref [%Lu, %u, %Lu]: %d\n",
6924                         key.objectid, key.type, key.offset, ret);
6925                 goto out;
6926         }
6927         if (ret > 0) {
6928                 fprintf(stderr, "Well that's odd, we just found this key "
6929                         "[%Lu, %u, %Lu]\n", key.objectid, key.type,
6930                         key.offset);
6931                 ret = -EINVAL;
6932                 goto out;
6933         }
6934         leaf = path->nodes[0];
6935         fi = btrfs_item_ptr(leaf, path->slots[0],
6936                             struct btrfs_file_extent_item);
6937
6938         if (btrfs_file_extent_compression(leaf, fi) &&
6939             dback->disk_bytenr != entry->bytenr) {
6940                 fprintf(stderr, "Ref doesn't match the record start and is "
6941                         "compressed, please take a btrfs-image of this file "
6942                         "system and send it to a btrfs developer so they can "
6943                         "complete this functionality for bytenr %Lu\n",
6944                         dback->disk_bytenr);
6945                 ret = -EINVAL;
6946                 goto out;
6947         }
6948
6949         if (dback->node.broken && dback->disk_bytenr != entry->bytenr) {
6950                 btrfs_set_file_extent_disk_bytenr(leaf, fi, entry->bytenr);
6951         } else if (dback->disk_bytenr > entry->bytenr) {
6952                 u64 off_diff, offset;
6953
6954                 off_diff = dback->disk_bytenr - entry->bytenr;
6955                 offset = btrfs_file_extent_offset(leaf, fi);
6956                 if (dback->disk_bytenr + offset +
6957                     btrfs_file_extent_num_bytes(leaf, fi) >
6958                     entry->bytenr + entry->bytes) {
6959                         fprintf(stderr, "Ref is past the entry end, please "
6960                                 "take a btrfs-image of this file system and "
6961                                 "send it to a btrfs developer, ref %Lu\n",
6962                                 dback->disk_bytenr);
6963                         ret = -EINVAL;
6964                         goto out;
6965                 }
6966                 offset += off_diff;
6967                 btrfs_set_file_extent_disk_bytenr(leaf, fi, entry->bytenr);
6968                 btrfs_set_file_extent_offset(leaf, fi, offset);
6969         } else if (dback->disk_bytenr < entry->bytenr) {
6970                 u64 offset;
6971
6972                 offset = btrfs_file_extent_offset(leaf, fi);
6973                 if (dback->disk_bytenr + offset < entry->bytenr) {
6974                         fprintf(stderr, "Ref is before the entry start, please"
6975                                 " take a btrfs-image of this file system and "
6976                                 "send it to a btrfs developer, ref %Lu\n",
6977                                 dback->disk_bytenr);
6978                         ret = -EINVAL;
6979                         goto out;
6980                 }
6981
6982                 offset += dback->disk_bytenr;
6983                 offset -= entry->bytenr;
6984                 btrfs_set_file_extent_disk_bytenr(leaf, fi, entry->bytenr);
6985                 btrfs_set_file_extent_offset(leaf, fi, offset);
6986         }
6987
6988         btrfs_set_file_extent_disk_num_bytes(leaf, fi, entry->bytes);
6989
6990         /*
6991          * Chances are if disk_num_bytes were wrong then so is ram_bytes, but
6992          * only do this if we aren't using compression, otherwise it's a
6993          * trickier case.
6994          */
6995         if (!btrfs_file_extent_compression(leaf, fi))
6996                 btrfs_set_file_extent_ram_bytes(leaf, fi, entry->bytes);
6997         else
6998                 printf("ram bytes may be wrong?\n");
6999         btrfs_mark_buffer_dirty(leaf);
7000 out:
7001         err = btrfs_commit_transaction(trans, root);
7002         btrfs_release_path(path);
7003         return ret ? ret : err;
7004 }
7005
7006 static int verify_backrefs(struct btrfs_fs_info *info, struct btrfs_path *path,
7007                            struct extent_record *rec)
7008 {
7009         struct extent_backref *back;
7010         struct data_backref *dback;
7011         struct extent_entry *entry, *best = NULL;
7012         LIST_HEAD(entries);
7013         int nr_entries = 0;
7014         int broken_entries = 0;
7015         int ret = 0;
7016         short mismatch = 0;
7017
7018         /*
7019          * Metadata is easy and the backrefs should always agree on bytenr and
7020          * size, if not we've got bigger issues.
7021          */
7022         if (rec->metadata)
7023                 return 0;
7024
7025         list_for_each_entry(back, &rec->backrefs, list) {
7026                 if (back->full_backref || !back->is_data)
7027                         continue;
7028
7029                 dback = to_data_backref(back);
7030
7031                 /*
7032                  * We only pay attention to backrefs that we found a real
7033                  * backref for.
7034                  */
7035                 if (dback->found_ref == 0)
7036                         continue;
7037
7038                 /*
7039                  * For now we only catch when the bytes don't match, not the
7040                  * bytenr.  We can easily do this at the same time, but I want
7041                  * to have a fs image to test on before we just add repair
7042                  * functionality willy-nilly so we know we won't screw up the
7043                  * repair.
7044                  */
7045
7046                 entry = find_entry(&entries, dback->disk_bytenr,
7047                                    dback->bytes);
7048                 if (!entry) {
7049                         entry = malloc(sizeof(struct extent_entry));
7050                         if (!entry) {
7051                                 ret = -ENOMEM;
7052                                 goto out;
7053                         }
7054                         memset(entry, 0, sizeof(*entry));
7055                         entry->bytenr = dback->disk_bytenr;
7056                         entry->bytes = dback->bytes;
7057                         list_add_tail(&entry->list, &entries);
7058                         nr_entries++;
7059                 }
7060
7061                 /*
7062                  * If we only have on entry we may think the entries agree when
7063                  * in reality they don't so we have to do some extra checking.
7064                  */
7065                 if (dback->disk_bytenr != rec->start ||
7066                     dback->bytes != rec->nr || back->broken)
7067                         mismatch = 1;
7068
7069                 if (back->broken) {
7070                         entry->broken++;
7071                         broken_entries++;
7072                 }
7073
7074                 entry->count++;
7075         }
7076
7077         /* Yay all the backrefs agree, carry on good sir */
7078         if (nr_entries <= 1 && !mismatch)
7079                 goto out;
7080
7081         fprintf(stderr, "attempting to repair backref discrepency for bytenr "
7082                 "%Lu\n", rec->start);
7083
7084         /*
7085          * First we want to see if the backrefs can agree amongst themselves who
7086          * is right, so figure out which one of the entries has the highest
7087          * count.
7088          */
7089         best = find_most_right_entry(&entries);
7090
7091         /*
7092          * Ok so we may have an even split between what the backrefs think, so
7093          * this is where we use the extent ref to see what it thinks.
7094          */
7095         if (!best) {
7096                 entry = find_entry(&entries, rec->start, rec->nr);
7097                 if (!entry && (!broken_entries || !rec->found_rec)) {
7098                         fprintf(stderr, "Backrefs don't agree with each other "
7099                                 "and extent record doesn't agree with anybody,"
7100                                 " so we can't fix bytenr %Lu bytes %Lu\n",
7101                                 rec->start, rec->nr);
7102                         ret = -EINVAL;
7103                         goto out;
7104                 } else if (!entry) {
7105                         /*
7106                          * Ok our backrefs were broken, we'll assume this is the
7107                          * correct value and add an entry for this range.
7108                          */
7109                         entry = malloc(sizeof(struct extent_entry));
7110                         if (!entry) {
7111                                 ret = -ENOMEM;
7112                                 goto out;
7113                         }
7114                         memset(entry, 0, sizeof(*entry));
7115                         entry->bytenr = rec->start;
7116                         entry->bytes = rec->nr;
7117                         list_add_tail(&entry->list, &entries);
7118                         nr_entries++;
7119                 }
7120                 entry->count++;
7121                 best = find_most_right_entry(&entries);
7122                 if (!best) {
7123                         fprintf(stderr, "Backrefs and extent record evenly "
7124                                 "split on who is right, this is going to "
7125                                 "require user input to fix bytenr %Lu bytes "
7126                                 "%Lu\n", rec->start, rec->nr);
7127                         ret = -EINVAL;
7128                         goto out;
7129                 }
7130         }
7131
7132         /*
7133          * I don't think this can happen currently as we'll abort() if we catch
7134          * this case higher up, but in case somebody removes that we still can't
7135          * deal with it properly here yet, so just bail out of that's the case.
7136          */
7137         if (best->bytenr != rec->start) {
7138                 fprintf(stderr, "Extent start and backref starts don't match, "
7139                         "please use btrfs-image on this file system and send "
7140                         "it to a btrfs developer so they can make fsck fix "
7141                         "this particular case.  bytenr is %Lu, bytes is %Lu\n",
7142                         rec->start, rec->nr);
7143                 ret = -EINVAL;
7144                 goto out;
7145         }
7146
7147         /*
7148          * Ok great we all agreed on an extent record, let's go find the real
7149          * references and fix up the ones that don't match.
7150          */
7151         list_for_each_entry(back, &rec->backrefs, list) {
7152                 if (back->full_backref || !back->is_data)
7153                         continue;
7154
7155                 dback = to_data_backref(back);
7156
7157                 /*
7158                  * Still ignoring backrefs that don't have a real ref attached
7159                  * to them.
7160                  */
7161                 if (dback->found_ref == 0)
7162                         continue;
7163
7164                 if (dback->bytes == best->bytes &&
7165                     dback->disk_bytenr == best->bytenr)
7166                         continue;
7167
7168                 ret = repair_ref(info, path, dback, best);
7169                 if (ret)
7170                         goto out;
7171         }
7172
7173         /*
7174          * Ok we messed with the actual refs, which means we need to drop our
7175          * entire cache and go back and rescan.  I know this is a huge pain and
7176          * adds a lot of extra work, but it's the only way to be safe.  Once all
7177          * the backrefs agree we may not need to do anything to the extent
7178          * record itself.
7179          */
7180         ret = -EAGAIN;
7181 out:
7182         while (!list_empty(&entries)) {
7183                 entry = list_entry(entries.next, struct extent_entry, list);
7184                 list_del_init(&entry->list);
7185                 free(entry);
7186         }
7187         return ret;
7188 }
7189
7190 static int process_duplicates(struct btrfs_root *root,
7191                               struct cache_tree *extent_cache,
7192                               struct extent_record *rec)
7193 {
7194         struct extent_record *good, *tmp;
7195         struct cache_extent *cache;
7196         int ret;
7197
7198         /*
7199          * If we found a extent record for this extent then return, or if we
7200          * have more than one duplicate we are likely going to need to delete
7201          * something.
7202          */
7203         if (rec->found_rec || rec->num_duplicates > 1)
7204                 return 0;
7205
7206         /* Shouldn't happen but just in case */
7207         BUG_ON(!rec->num_duplicates);
7208
7209         /*
7210          * So this happens if we end up with a backref that doesn't match the
7211          * actual extent entry.  So either the backref is bad or the extent
7212          * entry is bad.  Either way we want to have the extent_record actually
7213          * reflect what we found in the extent_tree, so we need to take the
7214          * duplicate out and use that as the extent_record since the only way we
7215          * get a duplicate is if we find a real life BTRFS_EXTENT_ITEM_KEY.
7216          */
7217         remove_cache_extent(extent_cache, &rec->cache);
7218
7219         good = to_extent_record(rec->dups.next);
7220         list_del_init(&good->list);
7221         INIT_LIST_HEAD(&good->backrefs);
7222         INIT_LIST_HEAD(&good->dups);
7223         good->cache.start = good->start;
7224         good->cache.size = good->nr;
7225         good->content_checked = 0;
7226         good->owner_ref_checked = 0;
7227         good->num_duplicates = 0;
7228         good->refs = rec->refs;
7229         list_splice_init(&rec->backrefs, &good->backrefs);
7230         while (1) {
7231                 cache = lookup_cache_extent(extent_cache, good->start,
7232                                             good->nr);
7233                 if (!cache)
7234                         break;
7235                 tmp = container_of(cache, struct extent_record, cache);
7236
7237                 /*
7238                  * If we find another overlapping extent and it's found_rec is
7239                  * set then it's a duplicate and we need to try and delete
7240                  * something.
7241                  */
7242                 if (tmp->found_rec || tmp->num_duplicates > 0) {
7243                         if (list_empty(&good->list))
7244                                 list_add_tail(&good->list,
7245                                               &duplicate_extents);
7246                         good->num_duplicates += tmp->num_duplicates + 1;
7247                         list_splice_init(&tmp->dups, &good->dups);
7248                         list_del_init(&tmp->list);
7249                         list_add_tail(&tmp->list, &good->dups);
7250                         remove_cache_extent(extent_cache, &tmp->cache);
7251                         continue;
7252                 }
7253
7254                 /*
7255                  * Ok we have another non extent item backed extent rec, so lets
7256                  * just add it to this extent and carry on like we did above.
7257                  */
7258                 good->refs += tmp->refs;
7259                 list_splice_init(&tmp->backrefs, &good->backrefs);
7260                 remove_cache_extent(extent_cache, &tmp->cache);
7261                 free(tmp);
7262         }
7263         ret = insert_cache_extent(extent_cache, &good->cache);
7264         BUG_ON(ret);
7265         free(rec);
7266         return good->num_duplicates ? 0 : 1;
7267 }
7268
7269 static int delete_duplicate_records(struct btrfs_root *root,
7270                                     struct extent_record *rec)
7271 {
7272         struct btrfs_trans_handle *trans;
7273         LIST_HEAD(delete_list);
7274         struct btrfs_path path;
7275         struct extent_record *tmp, *good, *n;
7276         int nr_del = 0;
7277         int ret = 0, err;
7278         struct btrfs_key key;
7279
7280         btrfs_init_path(&path);
7281
7282         good = rec;
7283         /* Find the record that covers all of the duplicates. */
7284         list_for_each_entry(tmp, &rec->dups, list) {
7285                 if (good->start < tmp->start)
7286                         continue;
7287                 if (good->nr > tmp->nr)
7288                         continue;
7289
7290                 if (tmp->start + tmp->nr < good->start + good->nr) {
7291                         fprintf(stderr, "Ok we have overlapping extents that "
7292                                 "aren't completely covered by each other, this "
7293                                 "is going to require more careful thought.  "
7294                                 "The extents are [%Lu-%Lu] and [%Lu-%Lu]\n",
7295                                 tmp->start, tmp->nr, good->start, good->nr);
7296                         abort();
7297                 }
7298                 good = tmp;
7299         }
7300
7301         if (good != rec)
7302                 list_add_tail(&rec->list, &delete_list);
7303
7304         list_for_each_entry_safe(tmp, n, &rec->dups, list) {
7305                 if (tmp == good)
7306                         continue;
7307                 list_move_tail(&tmp->list, &delete_list);
7308         }
7309
7310         root = root->fs_info->extent_root;
7311         trans = btrfs_start_transaction(root, 1);
7312         if (IS_ERR(trans)) {
7313                 ret = PTR_ERR(trans);
7314                 goto out;
7315         }
7316
7317         list_for_each_entry(tmp, &delete_list, list) {
7318                 if (tmp->found_rec == 0)
7319                         continue;
7320                 key.objectid = tmp->start;
7321                 key.type = BTRFS_EXTENT_ITEM_KEY;
7322                 key.offset = tmp->nr;
7323
7324                 /* Shouldn't happen but just in case */
7325                 if (tmp->metadata) {
7326                         fprintf(stderr, "Well this shouldn't happen, extent "
7327                                 "record overlaps but is metadata? "
7328                                 "[%Lu, %Lu]\n", tmp->start, tmp->nr);
7329                         abort();
7330                 }
7331
7332                 ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
7333                 if (ret) {
7334                         if (ret > 0)
7335                                 ret = -EINVAL;
7336                         break;
7337                 }
7338                 ret = btrfs_del_item(trans, root, &path);
7339                 if (ret)
7340                         break;
7341                 btrfs_release_path(&path);
7342                 nr_del++;
7343         }
7344         err = btrfs_commit_transaction(trans, root);
7345         if (err && !ret)
7346                 ret = err;
7347 out:
7348         while (!list_empty(&delete_list)) {
7349                 tmp = to_extent_record(delete_list.next);
7350                 list_del_init(&tmp->list);
7351                 if (tmp == rec)
7352                         continue;
7353                 free(tmp);
7354         }
7355
7356         while (!list_empty(&rec->dups)) {
7357                 tmp = to_extent_record(rec->dups.next);
7358                 list_del_init(&tmp->list);
7359                 free(tmp);
7360         }
7361
7362         btrfs_release_path(&path);
7363
7364         if (!ret && !nr_del)
7365                 rec->num_duplicates = 0;
7366
7367         return ret ? ret : nr_del;
7368 }
7369
7370 static int find_possible_backrefs(struct btrfs_fs_info *info,
7371                                   struct btrfs_path *path,
7372                                   struct cache_tree *extent_cache,
7373                                   struct extent_record *rec)
7374 {
7375         struct btrfs_root *root;
7376         struct extent_backref *back;
7377         struct data_backref *dback;
7378         struct cache_extent *cache;
7379         struct btrfs_file_extent_item *fi;
7380         struct btrfs_key key;
7381         u64 bytenr, bytes;
7382         int ret;
7383
7384         list_for_each_entry(back, &rec->backrefs, list) {
7385                 /* Don't care about full backrefs (poor unloved backrefs) */
7386                 if (back->full_backref || !back->is_data)
7387                         continue;
7388
7389                 dback = to_data_backref(back);
7390
7391                 /* We found this one, we don't need to do a lookup */
7392                 if (dback->found_ref)
7393                         continue;
7394
7395                 key.objectid = dback->root;
7396                 key.type = BTRFS_ROOT_ITEM_KEY;
7397                 key.offset = (u64)-1;
7398
7399                 root = btrfs_read_fs_root(info, &key);
7400
7401                 /* No root, definitely a bad ref, skip */
7402                 if (IS_ERR(root) && PTR_ERR(root) == -ENOENT)
7403                         continue;
7404                 /* Other err, exit */
7405                 if (IS_ERR(root))
7406                         return PTR_ERR(root);
7407
7408                 key.objectid = dback->owner;
7409                 key.type = BTRFS_EXTENT_DATA_KEY;
7410                 key.offset = dback->offset;
7411                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
7412                 if (ret) {
7413                         btrfs_release_path(path);
7414                         if (ret < 0)
7415                                 return ret;
7416                         /* Didn't find it, we can carry on */
7417                         ret = 0;
7418                         continue;
7419                 }
7420
7421                 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
7422                                     struct btrfs_file_extent_item);
7423                 bytenr = btrfs_file_extent_disk_bytenr(path->nodes[0], fi);
7424                 bytes = btrfs_file_extent_disk_num_bytes(path->nodes[0], fi);
7425                 btrfs_release_path(path);
7426                 cache = lookup_cache_extent(extent_cache, bytenr, 1);
7427                 if (cache) {
7428                         struct extent_record *tmp;
7429                         tmp = container_of(cache, struct extent_record, cache);
7430
7431                         /*
7432                          * If we found an extent record for the bytenr for this
7433                          * particular backref then we can't add it to our
7434                          * current extent record.  We only want to add backrefs
7435                          * that don't have a corresponding extent item in the
7436                          * extent tree since they likely belong to this record
7437                          * and we need to fix it if it doesn't match bytenrs.
7438                          */
7439                         if  (tmp->found_rec)
7440                                 continue;
7441                 }
7442
7443                 dback->found_ref += 1;
7444                 dback->disk_bytenr = bytenr;
7445                 dback->bytes = bytes;
7446
7447                 /*
7448                  * Set this so the verify backref code knows not to trust the
7449                  * values in this backref.
7450                  */
7451                 back->broken = 1;
7452         }
7453
7454         return 0;
7455 }
7456
7457 /*
7458  * Record orphan data ref into corresponding root.
7459  *
7460  * Return 0 if the extent item contains data ref and recorded.
7461  * Return 1 if the extent item contains no useful data ref
7462  *   On that case, it may contains only shared_dataref or metadata backref
7463  *   or the file extent exists(this should be handled by the extent bytenr
7464  *   recovery routine)
7465  * Return <0 if something goes wrong.
7466  */
7467 static int record_orphan_data_extents(struct btrfs_fs_info *fs_info,
7468                                       struct extent_record *rec)
7469 {
7470         struct btrfs_key key;
7471         struct btrfs_root *dest_root;
7472         struct extent_backref *back;
7473         struct data_backref *dback;
7474         struct orphan_data_extent *orphan;
7475         struct btrfs_path path;
7476         int recorded_data_ref = 0;
7477         int ret = 0;
7478
7479         if (rec->metadata)
7480                 return 1;
7481         btrfs_init_path(&path);
7482         list_for_each_entry(back, &rec->backrefs, list) {
7483                 if (back->full_backref || !back->is_data ||
7484                     !back->found_extent_tree)
7485                         continue;
7486                 dback = to_data_backref(back);
7487                 if (dback->found_ref)
7488                         continue;
7489                 key.objectid = dback->root;
7490                 key.type = BTRFS_ROOT_ITEM_KEY;
7491                 key.offset = (u64)-1;
7492
7493                 dest_root = btrfs_read_fs_root(fs_info, &key);
7494
7495                 /* For non-exist root we just skip it */
7496                 if (IS_ERR(dest_root) || !dest_root)
7497                         continue;
7498
7499                 key.objectid = dback->owner;
7500                 key.type = BTRFS_EXTENT_DATA_KEY;
7501                 key.offset = dback->offset;
7502
7503                 ret = btrfs_search_slot(NULL, dest_root, &key, &path, 0, 0);
7504                 btrfs_release_path(&path);
7505                 /*
7506                  * For ret < 0, it's OK since the fs-tree may be corrupted,
7507                  * we need to record it for inode/file extent rebuild.
7508                  * For ret > 0, we record it only for file extent rebuild.
7509                  * For ret == 0, the file extent exists but only bytenr
7510                  * mismatch, let the original bytenr fix routine to handle,
7511                  * don't record it.
7512                  */
7513                 if (ret == 0)
7514                         continue;
7515                 ret = 0;
7516                 orphan = malloc(sizeof(*orphan));
7517                 if (!orphan) {
7518                         ret = -ENOMEM;
7519                         goto out;
7520                 }
7521                 INIT_LIST_HEAD(&orphan->list);
7522                 orphan->root = dback->root;
7523                 orphan->objectid = dback->owner;
7524                 orphan->offset = dback->offset;
7525                 orphan->disk_bytenr = rec->cache.start;
7526                 orphan->disk_len = rec->cache.size;
7527                 list_add(&dest_root->orphan_data_extents, &orphan->list);
7528                 recorded_data_ref = 1;
7529         }
7530 out:
7531         btrfs_release_path(&path);
7532         if (!ret)
7533                 return !recorded_data_ref;
7534         else
7535                 return ret;
7536 }
7537
7538 /*
7539  * when an incorrect extent item is found, this will delete
7540  * all of the existing entries for it and recreate them
7541  * based on what the tree scan found.
7542  */
7543 static int fixup_extent_refs(struct btrfs_fs_info *info,
7544                              struct cache_tree *extent_cache,
7545                              struct extent_record *rec)
7546 {
7547         struct btrfs_trans_handle *trans = NULL;
7548         int ret;
7549         struct btrfs_path path;
7550         struct list_head *cur = rec->backrefs.next;
7551         struct cache_extent *cache;
7552         struct extent_backref *back;
7553         int allocated = 0;
7554         u64 flags = 0;
7555
7556         if (rec->flag_block_full_backref)
7557                 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
7558
7559         btrfs_init_path(&path);
7560         if (rec->refs != rec->extent_item_refs && !rec->metadata) {
7561                 /*
7562                  * Sometimes the backrefs themselves are so broken they don't
7563                  * get attached to any meaningful rec, so first go back and
7564                  * check any of our backrefs that we couldn't find and throw
7565                  * them into the list if we find the backref so that
7566                  * verify_backrefs can figure out what to do.
7567                  */
7568                 ret = find_possible_backrefs(info, &path, extent_cache, rec);
7569                 if (ret < 0)
7570                         goto out;
7571         }
7572
7573         /* step one, make sure all of the backrefs agree */
7574         ret = verify_backrefs(info, &path, rec);
7575         if (ret < 0)
7576                 goto out;
7577
7578         trans = btrfs_start_transaction(info->extent_root, 1);
7579         if (IS_ERR(trans)) {
7580                 ret = PTR_ERR(trans);
7581                 goto out;
7582         }
7583
7584         /* step two, delete all the existing records */
7585         ret = delete_extent_records(trans, info->extent_root, &path,
7586                                     rec->start, rec->max_size);
7587
7588         if (ret < 0)
7589                 goto out;
7590
7591         /* was this block corrupt?  If so, don't add references to it */
7592         cache = lookup_cache_extent(info->corrupt_blocks,
7593                                     rec->start, rec->max_size);
7594         if (cache) {
7595                 ret = 0;
7596                 goto out;
7597         }
7598
7599         /* step three, recreate all the refs we did find */
7600         while(cur != &rec->backrefs) {
7601                 back = to_extent_backref(cur);
7602                 cur = cur->next;
7603
7604                 /*
7605                  * if we didn't find any references, don't create a
7606                  * new extent record
7607                  */
7608                 if (!back->found_ref)
7609                         continue;
7610
7611                 rec->bad_full_backref = 0;
7612                 ret = record_extent(trans, info, &path, rec, back, allocated, flags);
7613                 allocated = 1;
7614
7615                 if (ret)
7616                         goto out;
7617         }
7618 out:
7619         if (trans) {
7620                 int err = btrfs_commit_transaction(trans, info->extent_root);
7621                 if (!ret)
7622                         ret = err;
7623         }
7624
7625         btrfs_release_path(&path);
7626         return ret;
7627 }
7628
7629 static int fixup_extent_flags(struct btrfs_fs_info *fs_info,
7630                               struct extent_record *rec)
7631 {
7632         struct btrfs_trans_handle *trans;
7633         struct btrfs_root *root = fs_info->extent_root;
7634         struct btrfs_path path;
7635         struct btrfs_extent_item *ei;
7636         struct btrfs_key key;
7637         u64 flags;
7638         int ret = 0;
7639
7640         key.objectid = rec->start;
7641         if (rec->metadata) {
7642                 key.type = BTRFS_METADATA_ITEM_KEY;
7643                 key.offset = rec->info_level;
7644         } else {
7645                 key.type = BTRFS_EXTENT_ITEM_KEY;
7646                 key.offset = rec->max_size;
7647         }
7648
7649         trans = btrfs_start_transaction(root, 0);
7650         if (IS_ERR(trans))
7651                 return PTR_ERR(trans);
7652
7653         btrfs_init_path(&path);
7654         ret = btrfs_search_slot(trans, root, &key, &path, 0, 1);
7655         if (ret < 0) {
7656                 btrfs_release_path(&path);
7657                 btrfs_commit_transaction(trans, root);
7658                 return ret;
7659         } else if (ret) {
7660                 fprintf(stderr, "Didn't find extent for %llu\n",
7661                         (unsigned long long)rec->start);
7662                 btrfs_release_path(&path);
7663                 btrfs_commit_transaction(trans, root);
7664                 return -ENOENT;
7665         }
7666
7667         ei = btrfs_item_ptr(path.nodes[0], path.slots[0],
7668                             struct btrfs_extent_item);
7669         flags = btrfs_extent_flags(path.nodes[0], ei);
7670         if (rec->flag_block_full_backref) {
7671                 fprintf(stderr, "setting full backref on %llu\n",
7672                         (unsigned long long)key.objectid);
7673                 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
7674         } else {
7675                 fprintf(stderr, "clearing full backref on %llu\n",
7676                         (unsigned long long)key.objectid);
7677                 flags &= ~BTRFS_BLOCK_FLAG_FULL_BACKREF;
7678         }
7679         btrfs_set_extent_flags(path.nodes[0], ei, flags);
7680         btrfs_mark_buffer_dirty(path.nodes[0]);
7681         btrfs_release_path(&path);
7682         return btrfs_commit_transaction(trans, root);
7683 }
7684
7685 /* right now we only prune from the extent allocation tree */
7686 static int prune_one_block(struct btrfs_trans_handle *trans,
7687                            struct btrfs_fs_info *info,
7688                            struct btrfs_corrupt_block *corrupt)
7689 {
7690         int ret;
7691         struct btrfs_path path;
7692         struct extent_buffer *eb;
7693         u64 found;
7694         int slot;
7695         int nritems;
7696         int level = corrupt->level + 1;
7697
7698         btrfs_init_path(&path);
7699 again:
7700         /* we want to stop at the parent to our busted block */
7701         path.lowest_level = level;
7702
7703         ret = btrfs_search_slot(trans, info->extent_root,
7704                                 &corrupt->key, &path, -1, 1);
7705
7706         if (ret < 0)
7707                 goto out;
7708
7709         eb = path.nodes[level];
7710         if (!eb) {
7711                 ret = -ENOENT;
7712                 goto out;
7713         }
7714
7715         /*
7716          * hopefully the search gave us the block we want to prune,
7717          * lets try that first
7718          */
7719         slot = path.slots[level];
7720         found =  btrfs_node_blockptr(eb, slot);
7721         if (found == corrupt->cache.start)
7722                 goto del_ptr;
7723
7724         nritems = btrfs_header_nritems(eb);
7725
7726         /* the search failed, lets scan this node and hope we find it */
7727         for (slot = 0; slot < nritems; slot++) {
7728                 found =  btrfs_node_blockptr(eb, slot);
7729                 if (found == corrupt->cache.start)
7730                         goto del_ptr;
7731         }
7732         /*
7733          * we couldn't find the bad block.  TODO, search all the nodes for pointers
7734          * to this block
7735          */
7736         if (eb == info->extent_root->node) {
7737                 ret = -ENOENT;
7738                 goto out;
7739         } else {
7740                 level++;
7741                 btrfs_release_path(&path);
7742                 goto again;
7743         }
7744
7745 del_ptr:
7746         printk("deleting pointer to block %Lu\n", corrupt->cache.start);
7747         ret = btrfs_del_ptr(trans, info->extent_root, &path, level, slot);
7748
7749 out:
7750         btrfs_release_path(&path);
7751         return ret;
7752 }
7753
7754 static int prune_corrupt_blocks(struct btrfs_fs_info *info)
7755 {
7756         struct btrfs_trans_handle *trans = NULL;
7757         struct cache_extent *cache;
7758         struct btrfs_corrupt_block *corrupt;
7759
7760         while (1) {
7761                 cache = search_cache_extent(info->corrupt_blocks, 0);
7762                 if (!cache)
7763                         break;
7764                 if (!trans) {
7765                         trans = btrfs_start_transaction(info->extent_root, 1);
7766                         if (IS_ERR(trans))
7767                                 return PTR_ERR(trans);
7768                 }
7769                 corrupt = container_of(cache, struct btrfs_corrupt_block, cache);
7770                 prune_one_block(trans, info, corrupt);
7771                 remove_cache_extent(info->corrupt_blocks, cache);
7772         }
7773         if (trans)
7774                 return btrfs_commit_transaction(trans, info->extent_root);
7775         return 0;
7776 }
7777
7778 static void reset_cached_block_groups(struct btrfs_fs_info *fs_info)
7779 {
7780         struct btrfs_block_group_cache *cache;
7781         u64 start, end;
7782         int ret;
7783
7784         while (1) {
7785                 ret = find_first_extent_bit(&fs_info->free_space_cache, 0,
7786                                             &start, &end, EXTENT_DIRTY);
7787                 if (ret)
7788                         break;
7789                 clear_extent_dirty(&fs_info->free_space_cache, start, end,
7790                                    GFP_NOFS);
7791         }
7792
7793         start = 0;
7794         while (1) {
7795                 cache = btrfs_lookup_first_block_group(fs_info, start);
7796                 if (!cache)
7797                         break;
7798                 if (cache->cached)
7799                         cache->cached = 0;
7800                 start = cache->key.objectid + cache->key.offset;
7801         }
7802 }
7803
7804 static int check_extent_refs(struct btrfs_root *root,
7805                              struct cache_tree *extent_cache)
7806 {
7807         struct extent_record *rec;
7808         struct cache_extent *cache;
7809         int err = 0;
7810         int ret = 0;
7811         int fixed = 0;
7812         int had_dups = 0;
7813         int recorded = 0;
7814
7815         if (repair) {
7816                 /*
7817                  * if we're doing a repair, we have to make sure
7818                  * we don't allocate from the problem extents.
7819                  * In the worst case, this will be all the
7820                  * extents in the FS
7821                  */
7822                 cache = search_cache_extent(extent_cache, 0);
7823                 while(cache) {
7824                         rec = container_of(cache, struct extent_record, cache);
7825                         set_extent_dirty(root->fs_info->excluded_extents,
7826                                          rec->start,
7827                                          rec->start + rec->max_size - 1,
7828                                          GFP_NOFS);
7829                         cache = next_cache_extent(cache);
7830                 }
7831
7832                 /* pin down all the corrupted blocks too */
7833                 cache = search_cache_extent(root->fs_info->corrupt_blocks, 0);
7834                 while(cache) {
7835                         set_extent_dirty(root->fs_info->excluded_extents,
7836                                          cache->start,
7837                                          cache->start + cache->size - 1,
7838                                          GFP_NOFS);
7839                         cache = next_cache_extent(cache);
7840                 }
7841                 prune_corrupt_blocks(root->fs_info);
7842                 reset_cached_block_groups(root->fs_info);
7843         }
7844
7845         reset_cached_block_groups(root->fs_info);
7846
7847         /*
7848          * We need to delete any duplicate entries we find first otherwise we
7849          * could mess up the extent tree when we have backrefs that actually
7850          * belong to a different extent item and not the weird duplicate one.
7851          */
7852         while (repair && !list_empty(&duplicate_extents)) {
7853                 rec = to_extent_record(duplicate_extents.next);
7854                 list_del_init(&rec->list);
7855
7856                 /* Sometimes we can find a backref before we find an actual
7857                  * extent, so we need to process it a little bit to see if there
7858                  * truly are multiple EXTENT_ITEM_KEY's for the same range, or
7859                  * if this is a backref screwup.  If we need to delete stuff
7860                  * process_duplicates() will return 0, otherwise it will return
7861                  * 1 and we
7862                  */
7863                 if (process_duplicates(root, extent_cache, rec))
7864                         continue;
7865                 ret = delete_duplicate_records(root, rec);
7866                 if (ret < 0)
7867                         return ret;
7868                 /*
7869                  * delete_duplicate_records will return the number of entries
7870                  * deleted, so if it's greater than 0 then we know we actually
7871                  * did something and we need to remove.
7872                  */
7873                 if (ret)
7874                         had_dups = 1;
7875         }
7876
7877         if (had_dups)
7878                 return -EAGAIN;
7879
7880         while(1) {
7881                 int cur_err = 0;
7882
7883                 fixed = 0;
7884                 recorded = 0;
7885                 cache = search_cache_extent(extent_cache, 0);
7886                 if (!cache)
7887                         break;
7888                 rec = container_of(cache, struct extent_record, cache);
7889                 if (rec->num_duplicates) {
7890                         fprintf(stderr, "extent item %llu has multiple extent "
7891                                 "items\n", (unsigned long long)rec->start);
7892                         err = 1;
7893                         cur_err = 1;
7894                 }
7895
7896                 if (rec->refs != rec->extent_item_refs) {
7897                         fprintf(stderr, "ref mismatch on [%llu %llu] ",
7898                                 (unsigned long long)rec->start,
7899                                 (unsigned long long)rec->nr);
7900                         fprintf(stderr, "extent item %llu, found %llu\n",
7901                                 (unsigned long long)rec->extent_item_refs,
7902                                 (unsigned long long)rec->refs);
7903                         ret = record_orphan_data_extents(root->fs_info, rec);
7904                         if (ret < 0)
7905                                 goto repair_abort;
7906                         if (ret == 0) {
7907                                 recorded = 1;
7908                         } else {
7909                                 /*
7910                                  * we can't use the extent to repair file
7911                                  * extent, let the fallback method handle it.
7912                                  */
7913                                 if (!fixed && repair) {
7914                                         ret = fixup_extent_refs(
7915                                                         root->fs_info,
7916                                                         extent_cache, rec);
7917                                         if (ret)
7918                                                 goto repair_abort;
7919                                         fixed = 1;
7920                                 }
7921                         }
7922                         err = 1;
7923                         cur_err = 1;
7924                 }
7925                 if (all_backpointers_checked(rec, 1)) {
7926                         fprintf(stderr, "backpointer mismatch on [%llu %llu]\n",
7927                                 (unsigned long long)rec->start,
7928                                 (unsigned long long)rec->nr);
7929
7930                         if (!fixed && !recorded && repair) {
7931                                 ret = fixup_extent_refs(root->fs_info,
7932                                                         extent_cache, rec);
7933                                 if (ret)
7934                                         goto repair_abort;
7935                                 fixed = 1;
7936                         }
7937                         cur_err = 1;
7938                         err = 1;
7939                 }
7940                 if (!rec->owner_ref_checked) {
7941                         fprintf(stderr, "owner ref check failed [%llu %llu]\n",
7942                                 (unsigned long long)rec->start,
7943                                 (unsigned long long)rec->nr);
7944                         if (!fixed && !recorded && repair) {
7945                                 ret = fixup_extent_refs(root->fs_info,
7946                                                         extent_cache, rec);
7947                                 if (ret)
7948                                         goto repair_abort;
7949                                 fixed = 1;
7950                         }
7951                         err = 1;
7952                         cur_err = 1;
7953                 }
7954                 if (rec->bad_full_backref) {
7955                         fprintf(stderr, "bad full backref, on [%llu]\n",
7956                                 (unsigned long long)rec->start);
7957                         if (repair) {
7958                                 ret = fixup_extent_flags(root->fs_info, rec);
7959                                 if (ret)
7960                                         goto repair_abort;
7961                                 fixed = 1;
7962                         }
7963                         err = 1;
7964                         cur_err = 1;
7965                 }
7966                 /*
7967                  * Although it's not a extent ref's problem, we reuse this
7968                  * routine for error reporting.
7969                  * No repair function yet.
7970                  */
7971                 if (rec->crossing_stripes) {
7972                         fprintf(stderr,
7973                                 "bad metadata [%llu, %llu) crossing stripe boundary\n",
7974                                 rec->start, rec->start + rec->max_size);
7975                         err = 1;
7976                         cur_err = 1;
7977                 }
7978
7979                 if (rec->wrong_chunk_type) {
7980                         fprintf(stderr,
7981                                 "bad extent [%llu, %llu), type mismatch with chunk\n",
7982                                 rec->start, rec->start + rec->max_size);
7983                         err = 1;
7984                         cur_err = 1;
7985                 }
7986
7987                 remove_cache_extent(extent_cache, cache);
7988                 free_all_extent_backrefs(rec);
7989                 if (!init_extent_tree && repair && (!cur_err || fixed))
7990                         clear_extent_dirty(root->fs_info->excluded_extents,
7991                                            rec->start,
7992                                            rec->start + rec->max_size - 1,
7993                                            GFP_NOFS);
7994                 free(rec);
7995         }
7996 repair_abort:
7997         if (repair) {
7998                 if (ret && ret != -EAGAIN) {
7999                         fprintf(stderr, "failed to repair damaged filesystem, aborting\n");
8000                         exit(1);
8001                 } else if (!ret) {
8002                         struct btrfs_trans_handle *trans;
8003
8004                         root = root->fs_info->extent_root;
8005                         trans = btrfs_start_transaction(root, 1);
8006                         if (IS_ERR(trans)) {
8007                                 ret = PTR_ERR(trans);
8008                                 goto repair_abort;
8009                         }
8010
8011                         btrfs_fix_block_accounting(trans, root);
8012                         ret = btrfs_commit_transaction(trans, root);
8013                         if (ret)
8014                                 goto repair_abort;
8015                 }
8016                 if (err)
8017                         fprintf(stderr, "repaired damaged extent references\n");
8018                 return ret;
8019         }
8020         return err;
8021 }
8022
8023 u64 calc_stripe_length(u64 type, u64 length, int num_stripes)
8024 {
8025         u64 stripe_size;
8026
8027         if (type & BTRFS_BLOCK_GROUP_RAID0) {
8028                 stripe_size = length;
8029                 stripe_size /= num_stripes;
8030         } else if (type & BTRFS_BLOCK_GROUP_RAID10) {
8031                 stripe_size = length * 2;
8032                 stripe_size /= num_stripes;
8033         } else if (type & BTRFS_BLOCK_GROUP_RAID5) {
8034                 stripe_size = length;
8035                 stripe_size /= (num_stripes - 1);
8036         } else if (type & BTRFS_BLOCK_GROUP_RAID6) {
8037                 stripe_size = length;
8038                 stripe_size /= (num_stripes - 2);
8039         } else {
8040                 stripe_size = length;
8041         }
8042         return stripe_size;
8043 }
8044
8045 /*
8046  * Check the chunk with its block group/dev list ref:
8047  * Return 0 if all refs seems valid.
8048  * Return 1 if part of refs seems valid, need later check for rebuild ref
8049  * like missing block group and needs to search extent tree to rebuild them.
8050  * Return -1 if essential refs are missing and unable to rebuild.
8051  */
8052 static int check_chunk_refs(struct chunk_record *chunk_rec,
8053                             struct block_group_tree *block_group_cache,
8054                             struct device_extent_tree *dev_extent_cache,
8055                             int silent)
8056 {
8057         struct cache_extent *block_group_item;
8058         struct block_group_record *block_group_rec;
8059         struct cache_extent *dev_extent_item;
8060         struct device_extent_record *dev_extent_rec;
8061         u64 devid;
8062         u64 offset;
8063         u64 length;
8064         int metadump_v2 = 0;
8065         int i;
8066         int ret = 0;
8067
8068         block_group_item = lookup_cache_extent(&block_group_cache->tree,
8069                                                chunk_rec->offset,
8070                                                chunk_rec->length);
8071         if (block_group_item) {
8072                 block_group_rec = container_of(block_group_item,
8073                                                struct block_group_record,
8074                                                cache);
8075                 if (chunk_rec->length != block_group_rec->offset ||
8076                     chunk_rec->offset != block_group_rec->objectid ||
8077                     (!metadump_v2 &&
8078                      chunk_rec->type_flags != block_group_rec->flags)) {
8079                         if (!silent)
8080                                 fprintf(stderr,
8081                                         "Chunk[%llu, %u, %llu]: length(%llu), offset(%llu), type(%llu) mismatch with block group[%llu, %u, %llu]: offset(%llu), objectid(%llu), flags(%llu)\n",
8082                                         chunk_rec->objectid,
8083                                         chunk_rec->type,
8084                                         chunk_rec->offset,
8085                                         chunk_rec->length,
8086                                         chunk_rec->offset,
8087                                         chunk_rec->type_flags,
8088                                         block_group_rec->objectid,
8089                                         block_group_rec->type,
8090                                         block_group_rec->offset,
8091                                         block_group_rec->offset,
8092                                         block_group_rec->objectid,
8093                                         block_group_rec->flags);
8094                         ret = -1;
8095                 } else {
8096                         list_del_init(&block_group_rec->list);
8097                         chunk_rec->bg_rec = block_group_rec;
8098                 }
8099         } else {
8100                 if (!silent)
8101                         fprintf(stderr,
8102                                 "Chunk[%llu, %u, %llu]: length(%llu), offset(%llu), type(%llu) is not found in block group\n",
8103                                 chunk_rec->objectid,
8104                                 chunk_rec->type,
8105                                 chunk_rec->offset,
8106                                 chunk_rec->length,
8107                                 chunk_rec->offset,
8108                                 chunk_rec->type_flags);
8109                 ret = 1;
8110         }
8111
8112         if (metadump_v2)
8113                 return ret;
8114
8115         length = calc_stripe_length(chunk_rec->type_flags, chunk_rec->length,
8116                                     chunk_rec->num_stripes);
8117         for (i = 0; i < chunk_rec->num_stripes; ++i) {
8118                 devid = chunk_rec->stripes[i].devid;
8119                 offset = chunk_rec->stripes[i].offset;
8120                 dev_extent_item = lookup_cache_extent2(&dev_extent_cache->tree,
8121                                                        devid, offset, length);
8122                 if (dev_extent_item) {
8123                         dev_extent_rec = container_of(dev_extent_item,
8124                                                 struct device_extent_record,
8125                                                 cache);
8126                         if (dev_extent_rec->objectid != devid ||
8127                             dev_extent_rec->offset != offset ||
8128                             dev_extent_rec->chunk_offset != chunk_rec->offset ||
8129                             dev_extent_rec->length != length) {
8130                                 if (!silent)
8131                                         fprintf(stderr,
8132                                                 "Chunk[%llu, %u, %llu] stripe[%llu, %llu] dismatch dev extent[%llu, %llu, %llu]\n",
8133                                                 chunk_rec->objectid,
8134                                                 chunk_rec->type,
8135                                                 chunk_rec->offset,
8136                                                 chunk_rec->stripes[i].devid,
8137                                                 chunk_rec->stripes[i].offset,
8138                                                 dev_extent_rec->objectid,
8139                                                 dev_extent_rec->offset,
8140                                                 dev_extent_rec->length);
8141                                 ret = -1;
8142                         } else {
8143                                 list_move(&dev_extent_rec->chunk_list,
8144                                           &chunk_rec->dextents);
8145                         }
8146                 } else {
8147                         if (!silent)
8148                                 fprintf(stderr,
8149                                         "Chunk[%llu, %u, %llu] stripe[%llu, %llu] is not found in dev extent\n",
8150                                         chunk_rec->objectid,
8151                                         chunk_rec->type,
8152                                         chunk_rec->offset,
8153                                         chunk_rec->stripes[i].devid,
8154                                         chunk_rec->stripes[i].offset);
8155                         ret = -1;
8156                 }
8157         }
8158         return ret;
8159 }
8160
8161 /* check btrfs_chunk -> btrfs_dev_extent / btrfs_block_group_item */
8162 int check_chunks(struct cache_tree *chunk_cache,
8163                  struct block_group_tree *block_group_cache,
8164                  struct device_extent_tree *dev_extent_cache,
8165                  struct list_head *good, struct list_head *bad,
8166                  struct list_head *rebuild, int silent)
8167 {
8168         struct cache_extent *chunk_item;
8169         struct chunk_record *chunk_rec;
8170         struct block_group_record *bg_rec;
8171         struct device_extent_record *dext_rec;
8172         int err;
8173         int ret = 0;
8174
8175         chunk_item = first_cache_extent(chunk_cache);
8176         while (chunk_item) {
8177                 chunk_rec = container_of(chunk_item, struct chunk_record,
8178                                          cache);
8179                 err = check_chunk_refs(chunk_rec, block_group_cache,
8180                                        dev_extent_cache, silent);
8181                 if (err < 0)
8182                         ret = err;
8183                 if (err == 0 && good)
8184                         list_add_tail(&chunk_rec->list, good);
8185                 if (err > 0 && rebuild)
8186                         list_add_tail(&chunk_rec->list, rebuild);
8187                 if (err < 0 && bad)
8188                         list_add_tail(&chunk_rec->list, bad);
8189                 chunk_item = next_cache_extent(chunk_item);
8190         }
8191
8192         list_for_each_entry(bg_rec, &block_group_cache->block_groups, list) {
8193                 if (!silent)
8194                         fprintf(stderr,
8195                                 "Block group[%llu, %llu] (flags = %llu) didn't find the relative chunk.\n",
8196                                 bg_rec->objectid,
8197                                 bg_rec->offset,
8198                                 bg_rec->flags);
8199                 if (!ret)
8200                         ret = 1;
8201         }
8202
8203         list_for_each_entry(dext_rec, &dev_extent_cache->no_chunk_orphans,
8204                             chunk_list) {
8205                 if (!silent)
8206                         fprintf(stderr,
8207                                 "Device extent[%llu, %llu, %llu] didn't find the relative chunk.\n",
8208                                 dext_rec->objectid,
8209                                 dext_rec->offset,
8210                                 dext_rec->length);
8211                 if (!ret)
8212                         ret = 1;
8213         }
8214         return ret;
8215 }
8216
8217
8218 static int check_device_used(struct device_record *dev_rec,
8219                              struct device_extent_tree *dext_cache)
8220 {
8221         struct cache_extent *cache;
8222         struct device_extent_record *dev_extent_rec;
8223         u64 total_byte = 0;
8224
8225         cache = search_cache_extent2(&dext_cache->tree, dev_rec->devid, 0);
8226         while (cache) {
8227                 dev_extent_rec = container_of(cache,
8228                                               struct device_extent_record,
8229                                               cache);
8230                 if (dev_extent_rec->objectid != dev_rec->devid)
8231                         break;
8232
8233                 list_del_init(&dev_extent_rec->device_list);
8234                 total_byte += dev_extent_rec->length;
8235                 cache = next_cache_extent(cache);
8236         }
8237
8238         if (total_byte != dev_rec->byte_used) {
8239                 fprintf(stderr,
8240                         "Dev extent's total-byte(%llu) is not equal to byte-used(%llu) in dev[%llu, %u, %llu]\n",
8241                         total_byte, dev_rec->byte_used, dev_rec->objectid,
8242                         dev_rec->type, dev_rec->offset);
8243                 return -1;
8244         } else {
8245                 return 0;
8246         }
8247 }
8248
8249 /* check btrfs_dev_item -> btrfs_dev_extent */
8250 static int check_devices(struct rb_root *dev_cache,
8251                          struct device_extent_tree *dev_extent_cache)
8252 {
8253         struct rb_node *dev_node;
8254         struct device_record *dev_rec;
8255         struct device_extent_record *dext_rec;
8256         int err;
8257         int ret = 0;
8258
8259         dev_node = rb_first(dev_cache);
8260         while (dev_node) {
8261                 dev_rec = container_of(dev_node, struct device_record, node);
8262                 err = check_device_used(dev_rec, dev_extent_cache);
8263                 if (err)
8264                         ret = err;
8265
8266                 dev_node = rb_next(dev_node);
8267         }
8268         list_for_each_entry(dext_rec, &dev_extent_cache->no_device_orphans,
8269                             device_list) {
8270                 fprintf(stderr,
8271                         "Device extent[%llu, %llu, %llu] didn't find its device.\n",
8272                         dext_rec->objectid, dext_rec->offset, dext_rec->length);
8273                 if (!ret)
8274                         ret = 1;
8275         }
8276         return ret;
8277 }
8278
8279 static int add_root_item_to_list(struct list_head *head,
8280                                   u64 objectid, u64 bytenr, u64 last_snapshot,
8281                                   u8 level, u8 drop_level,
8282                                   int level_size, struct btrfs_key *drop_key)
8283 {
8284
8285         struct root_item_record *ri_rec;
8286         ri_rec = malloc(sizeof(*ri_rec));
8287         if (!ri_rec)
8288                 return -ENOMEM;
8289         ri_rec->bytenr = bytenr;
8290         ri_rec->objectid = objectid;
8291         ri_rec->level = level;
8292         ri_rec->level_size = level_size;
8293         ri_rec->drop_level = drop_level;
8294         ri_rec->last_snapshot = last_snapshot;
8295         if (drop_key)
8296                 memcpy(&ri_rec->drop_key, drop_key, sizeof(*drop_key));
8297         list_add_tail(&ri_rec->list, head);
8298
8299         return 0;
8300 }
8301
8302 static void free_root_item_list(struct list_head *list)
8303 {
8304         struct root_item_record *ri_rec;
8305
8306         while (!list_empty(list)) {
8307                 ri_rec = list_first_entry(list, struct root_item_record,
8308                                           list);
8309                 list_del_init(&ri_rec->list);
8310                 free(ri_rec);
8311         }
8312 }
8313
8314 static int deal_root_from_list(struct list_head *list,
8315                                struct btrfs_root *root,
8316                                struct block_info *bits,
8317                                int bits_nr,
8318                                struct cache_tree *pending,
8319                                struct cache_tree *seen,
8320                                struct cache_tree *reada,
8321                                struct cache_tree *nodes,
8322                                struct cache_tree *extent_cache,
8323                                struct cache_tree *chunk_cache,
8324                                struct rb_root *dev_cache,
8325                                struct block_group_tree *block_group_cache,
8326                                struct device_extent_tree *dev_extent_cache)
8327 {
8328         int ret = 0;
8329         u64 last;
8330
8331         while (!list_empty(list)) {
8332                 struct root_item_record *rec;
8333                 struct extent_buffer *buf;
8334                 rec = list_entry(list->next,
8335                                  struct root_item_record, list);
8336                 last = 0;
8337                 buf = read_tree_block(root->fs_info->tree_root,
8338                                       rec->bytenr, rec->level_size, 0);
8339                 if (!extent_buffer_uptodate(buf)) {
8340                         free_extent_buffer(buf);
8341                         ret = -EIO;
8342                         break;
8343                 }
8344                 ret = add_root_to_pending(buf, extent_cache, pending,
8345                                     seen, nodes, rec->objectid);
8346                 if (ret < 0)
8347                         break;
8348                 /*
8349                  * To rebuild extent tree, we need deal with snapshot
8350                  * one by one, otherwise we deal with node firstly which
8351                  * can maximize readahead.
8352                  */
8353                 while (1) {
8354                         ret = run_next_block(root, bits, bits_nr, &last,
8355                                              pending, seen, reada, nodes,
8356                                              extent_cache, chunk_cache,
8357                                              dev_cache, block_group_cache,
8358                                              dev_extent_cache, rec);
8359                         if (ret != 0)
8360                                 break;
8361                 }
8362                 free_extent_buffer(buf);
8363                 list_del(&rec->list);
8364                 free(rec);
8365                 if (ret < 0)
8366                         break;
8367         }
8368         while (ret >= 0) {
8369                 ret = run_next_block(root, bits, bits_nr, &last, pending, seen,
8370                                      reada, nodes, extent_cache, chunk_cache,
8371                                      dev_cache, block_group_cache,
8372                                      dev_extent_cache, NULL);
8373                 if (ret != 0) {
8374                         if (ret > 0)
8375                                 ret = 0;
8376                         break;
8377                 }
8378         }
8379         return ret;
8380 }
8381
8382 static int check_chunks_and_extents(struct btrfs_root *root)
8383 {
8384         struct rb_root dev_cache;
8385         struct cache_tree chunk_cache;
8386         struct block_group_tree block_group_cache;
8387         struct device_extent_tree dev_extent_cache;
8388         struct cache_tree extent_cache;
8389         struct cache_tree seen;
8390         struct cache_tree pending;
8391         struct cache_tree reada;
8392         struct cache_tree nodes;
8393         struct extent_io_tree excluded_extents;
8394         struct cache_tree corrupt_blocks;
8395         struct btrfs_path path;
8396         struct btrfs_key key;
8397         struct btrfs_key found_key;
8398         int ret, err = 0;
8399         struct block_info *bits;
8400         int bits_nr;
8401         struct extent_buffer *leaf;
8402         int slot;
8403         struct btrfs_root_item ri;
8404         struct list_head dropping_trees;
8405         struct list_head normal_trees;
8406         struct btrfs_root *root1;
8407         u64 objectid;
8408         u32 level_size;
8409         u8 level;
8410
8411         dev_cache = RB_ROOT;
8412         cache_tree_init(&chunk_cache);
8413         block_group_tree_init(&block_group_cache);
8414         device_extent_tree_init(&dev_extent_cache);
8415
8416         cache_tree_init(&extent_cache);
8417         cache_tree_init(&seen);
8418         cache_tree_init(&pending);
8419         cache_tree_init(&nodes);
8420         cache_tree_init(&reada);
8421         cache_tree_init(&corrupt_blocks);
8422         extent_io_tree_init(&excluded_extents);
8423         INIT_LIST_HEAD(&dropping_trees);
8424         INIT_LIST_HEAD(&normal_trees);
8425
8426         if (repair) {
8427                 root->fs_info->excluded_extents = &excluded_extents;
8428                 root->fs_info->fsck_extent_cache = &extent_cache;
8429                 root->fs_info->free_extent_hook = free_extent_hook;
8430                 root->fs_info->corrupt_blocks = &corrupt_blocks;
8431         }
8432
8433         bits_nr = 1024;
8434         bits = malloc(bits_nr * sizeof(struct block_info));
8435         if (!bits) {
8436                 perror("malloc");
8437                 exit(1);
8438         }
8439
8440         if (ctx.progress_enabled) {
8441                 ctx.tp = TASK_EXTENTS;
8442                 task_start(ctx.info);
8443         }
8444
8445 again:
8446         root1 = root->fs_info->tree_root;
8447         level = btrfs_header_level(root1->node);
8448         ret = add_root_item_to_list(&normal_trees, root1->root_key.objectid,
8449                                     root1->node->start, 0, level, 0,
8450                                     root1->nodesize, NULL);
8451         if (ret < 0)
8452                 goto out;
8453         root1 = root->fs_info->chunk_root;
8454         level = btrfs_header_level(root1->node);
8455         ret = add_root_item_to_list(&normal_trees, root1->root_key.objectid,
8456                                     root1->node->start, 0, level, 0,
8457                                     root1->nodesize, NULL);
8458         if (ret < 0)
8459                 goto out;
8460         btrfs_init_path(&path);
8461         key.offset = 0;
8462         key.objectid = 0;
8463         key.type = BTRFS_ROOT_ITEM_KEY;
8464         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
8465                                         &key, &path, 0, 0);
8466         if (ret < 0)
8467                 goto out;
8468         while(1) {
8469                 leaf = path.nodes[0];
8470                 slot = path.slots[0];
8471                 if (slot >= btrfs_header_nritems(path.nodes[0])) {
8472                         ret = btrfs_next_leaf(root, &path);
8473                         if (ret != 0)
8474                                 break;
8475                         leaf = path.nodes[0];
8476                         slot = path.slots[0];
8477                 }
8478                 btrfs_item_key_to_cpu(leaf, &found_key, path.slots[0]);
8479                 if (found_key.type == BTRFS_ROOT_ITEM_KEY) {
8480                         unsigned long offset;
8481                         u64 last_snapshot;
8482
8483                         offset = btrfs_item_ptr_offset(leaf, path.slots[0]);
8484                         read_extent_buffer(leaf, &ri, offset, sizeof(ri));
8485                         last_snapshot = btrfs_root_last_snapshot(&ri);
8486                         if (btrfs_disk_key_objectid(&ri.drop_progress) == 0) {
8487                                 level = btrfs_root_level(&ri);
8488                                 level_size = root->nodesize;
8489                                 ret = add_root_item_to_list(&normal_trees,
8490                                                 found_key.objectid,
8491                                                 btrfs_root_bytenr(&ri),
8492                                                 last_snapshot, level,
8493                                                 0, level_size, NULL);
8494                                 if (ret < 0)
8495                                         goto out;
8496                         } else {
8497                                 level = btrfs_root_level(&ri);
8498                                 level_size = root->nodesize;
8499                                 objectid = found_key.objectid;
8500                                 btrfs_disk_key_to_cpu(&found_key,
8501                                                       &ri.drop_progress);
8502                                 ret = add_root_item_to_list(&dropping_trees,
8503                                                 objectid,
8504                                                 btrfs_root_bytenr(&ri),
8505                                                 last_snapshot, level,
8506                                                 ri.drop_level,
8507                                                 level_size, &found_key);
8508                                 if (ret < 0)
8509                                         goto out;
8510                         }
8511                 }
8512                 path.slots[0]++;
8513         }
8514         btrfs_release_path(&path);
8515
8516         /*
8517          * check_block can return -EAGAIN if it fixes something, please keep
8518          * this in mind when dealing with return values from these functions, if
8519          * we get -EAGAIN we want to fall through and restart the loop.
8520          */
8521         ret = deal_root_from_list(&normal_trees, root, bits, bits_nr, &pending,
8522                                   &seen, &reada, &nodes, &extent_cache,
8523                                   &chunk_cache, &dev_cache, &block_group_cache,
8524                                   &dev_extent_cache);
8525         if (ret < 0) {
8526                 if (ret == -EAGAIN)
8527                         goto loop;
8528                 goto out;
8529         }
8530         ret = deal_root_from_list(&dropping_trees, root, bits, bits_nr,
8531                                   &pending, &seen, &reada, &nodes,
8532                                   &extent_cache, &chunk_cache, &dev_cache,
8533                                   &block_group_cache, &dev_extent_cache);
8534         if (ret < 0) {
8535                 if (ret == -EAGAIN)
8536                         goto loop;
8537                 goto out;
8538         }
8539
8540         ret = check_chunks(&chunk_cache, &block_group_cache,
8541                            &dev_extent_cache, NULL, NULL, NULL, 0);
8542         if (ret) {
8543                 if (ret == -EAGAIN)
8544                         goto loop;
8545                 err = ret;
8546         }
8547
8548         ret = check_extent_refs(root, &extent_cache);
8549         if (ret < 0) {
8550                 if (ret == -EAGAIN)
8551                         goto loop;
8552                 goto out;
8553         }
8554
8555         ret = check_devices(&dev_cache, &dev_extent_cache);
8556         if (ret && err)
8557                 ret = err;
8558
8559 out:
8560         task_stop(ctx.info);
8561         if (repair) {
8562                 free_corrupt_blocks_tree(root->fs_info->corrupt_blocks);
8563                 extent_io_tree_cleanup(&excluded_extents);
8564                 root->fs_info->fsck_extent_cache = NULL;
8565                 root->fs_info->free_extent_hook = NULL;
8566                 root->fs_info->corrupt_blocks = NULL;
8567                 root->fs_info->excluded_extents = NULL;
8568         }
8569         free(bits);
8570         free_chunk_cache_tree(&chunk_cache);
8571         free_device_cache_tree(&dev_cache);
8572         free_block_group_tree(&block_group_cache);
8573         free_device_extent_tree(&dev_extent_cache);
8574         free_extent_cache_tree(&seen);
8575         free_extent_cache_tree(&pending);
8576         free_extent_cache_tree(&reada);
8577         free_extent_cache_tree(&nodes);
8578         return ret;
8579 loop:
8580         free_corrupt_blocks_tree(root->fs_info->corrupt_blocks);
8581         free_extent_cache_tree(&seen);
8582         free_extent_cache_tree(&pending);
8583         free_extent_cache_tree(&reada);
8584         free_extent_cache_tree(&nodes);
8585         free_chunk_cache_tree(&chunk_cache);
8586         free_block_group_tree(&block_group_cache);
8587         free_device_cache_tree(&dev_cache);
8588         free_device_extent_tree(&dev_extent_cache);
8589         free_extent_record_cache(root->fs_info, &extent_cache);
8590         free_root_item_list(&normal_trees);
8591         free_root_item_list(&dropping_trees);
8592         extent_io_tree_cleanup(&excluded_extents);
8593         goto again;
8594 }
8595
8596 /*
8597  * Check backrefs of a tree block given by @bytenr or @eb.
8598  *
8599  * @root:       the root containing the @bytenr or @eb
8600  * @eb:         tree block extent buffer, can be NULL
8601  * @bytenr:     bytenr of the tree block to search
8602  * @level:      tree level of the tree block
8603  * @owner:      owner of the tree block
8604  *
8605  * Return >0 for any error found and output error message
8606  * Return 0 for no error found
8607  */
8608 static int check_tree_block_ref(struct btrfs_root *root,
8609                                 struct extent_buffer *eb, u64 bytenr,
8610                                 int level, u64 owner)
8611 {
8612         struct btrfs_key key;
8613         struct btrfs_root *extent_root = root->fs_info->extent_root;
8614         struct btrfs_path path;
8615         struct btrfs_extent_item *ei;
8616         struct btrfs_extent_inline_ref *iref;
8617         struct extent_buffer *leaf;
8618         unsigned long end;
8619         unsigned long ptr;
8620         int slot;
8621         int skinny_level;
8622         int type;
8623         u32 nodesize = root->nodesize;
8624         u32 item_size;
8625         u64 offset;
8626         int found_ref = 0;
8627         int err = 0;
8628         int ret;
8629
8630         btrfs_init_path(&path);
8631         key.objectid = bytenr;
8632         if (btrfs_fs_incompat(root->fs_info,
8633                               BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA))
8634                 key.type = BTRFS_METADATA_ITEM_KEY;
8635         else
8636                 key.type = BTRFS_EXTENT_ITEM_KEY;
8637         key.offset = (u64)-1;
8638
8639         /* Search for the backref in extent tree */
8640         ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
8641         if (ret < 0) {
8642                 err |= BACKREF_MISSING;
8643                 goto out;
8644         }
8645         ret = btrfs_previous_extent_item(extent_root, &path, bytenr);
8646         if (ret) {
8647                 err |= BACKREF_MISSING;
8648                 goto out;
8649         }
8650
8651         leaf = path.nodes[0];
8652         slot = path.slots[0];
8653         btrfs_item_key_to_cpu(leaf, &key, slot);
8654
8655         ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
8656
8657         if (key.type == BTRFS_METADATA_ITEM_KEY) {
8658                 skinny_level = (int)key.offset;
8659                 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
8660         } else {
8661                 struct btrfs_tree_block_info *info;
8662
8663                 info = (struct btrfs_tree_block_info *)(ei + 1);
8664                 skinny_level = btrfs_tree_block_level(leaf, info);
8665                 iref = (struct btrfs_extent_inline_ref *)(info + 1);
8666         }
8667
8668         if (eb) {
8669                 u64 header_gen;
8670                 u64 extent_gen;
8671
8672                 if (!(btrfs_extent_flags(leaf, ei) &
8673                       BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
8674                         error(
8675                 "extent[%llu %u] backref type mismatch, missing bit: %llx",
8676                                 key.objectid, nodesize,
8677                                 BTRFS_EXTENT_FLAG_TREE_BLOCK);
8678                         err = BACKREF_MISMATCH;
8679                 }
8680                 header_gen = btrfs_header_generation(eb);
8681                 extent_gen = btrfs_extent_generation(leaf, ei);
8682                 if (header_gen != extent_gen) {
8683                         error(
8684         "extent[%llu %u] backref generation mismatch, wanted: %llu, have: %llu",
8685                                 key.objectid, nodesize, header_gen,
8686                                 extent_gen);
8687                         err = BACKREF_MISMATCH;
8688                 }
8689                 if (level != skinny_level) {
8690                         error(
8691                         "extent[%llu %u] level mismatch, wanted: %u, have: %u",
8692                                 key.objectid, nodesize, level, skinny_level);
8693                         err = BACKREF_MISMATCH;
8694                 }
8695                 if (!is_fstree(owner) && btrfs_extent_refs(leaf, ei) != 1) {
8696                         error(
8697                         "extent[%llu %u] is referred by other roots than %llu",
8698                                 key.objectid, nodesize, root->objectid);
8699                         err = BACKREF_MISMATCH;
8700                 }
8701         }
8702
8703         /*
8704          * Iterate the extent/metadata item to find the exact backref
8705          */
8706         item_size = btrfs_item_size_nr(leaf, slot);
8707         ptr = (unsigned long)iref;
8708         end = (unsigned long)ei + item_size;
8709         while (ptr < end) {
8710                 iref = (struct btrfs_extent_inline_ref *)ptr;
8711                 type = btrfs_extent_inline_ref_type(leaf, iref);
8712                 offset = btrfs_extent_inline_ref_offset(leaf, iref);
8713
8714                 if (type == BTRFS_TREE_BLOCK_REF_KEY &&
8715                         (offset == root->objectid || offset == owner)) {
8716                         found_ref = 1;
8717                 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
8718                         /* Check if the backref points to valid referencer */
8719                         found_ref = !check_tree_block_ref(root, NULL, offset,
8720                                                           level + 1, owner);
8721                 }
8722
8723                 if (found_ref)
8724                         break;
8725                 ptr += btrfs_extent_inline_ref_size(type);
8726         }
8727
8728         /*
8729          * Inlined extent item doesn't have what we need, check
8730          * TREE_BLOCK_REF_KEY
8731          */
8732         if (!found_ref) {
8733                 btrfs_release_path(&path);
8734                 key.objectid = bytenr;
8735                 key.type = BTRFS_TREE_BLOCK_REF_KEY;
8736                 key.offset = root->objectid;
8737
8738                 ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
8739                 if (!ret)
8740                         found_ref = 1;
8741         }
8742         if (!found_ref)
8743                 err |= BACKREF_MISSING;
8744 out:
8745         btrfs_release_path(&path);
8746         if (eb && (err & BACKREF_MISSING))
8747                 error("extent[%llu %u] backref lost (owner: %llu, level: %u)",
8748                         bytenr, nodesize, owner, level);
8749         return err;
8750 }
8751
8752 /*
8753  * Check EXTENT_DATA item, mainly for its dbackref in extent tree
8754  *
8755  * Return >0 any error found and output error message
8756  * Return 0 for no error found
8757  */
8758 static int check_extent_data_item(struct btrfs_root *root,
8759                                   struct extent_buffer *eb, int slot)
8760 {
8761         struct btrfs_file_extent_item *fi;
8762         struct btrfs_path path;
8763         struct btrfs_root *extent_root = root->fs_info->extent_root;
8764         struct btrfs_key fi_key;
8765         struct btrfs_key dbref_key;
8766         struct extent_buffer *leaf;
8767         struct btrfs_extent_item *ei;
8768         struct btrfs_extent_inline_ref *iref;
8769         struct btrfs_extent_data_ref *dref;
8770         u64 owner;
8771         u64 file_extent_gen;
8772         u64 disk_bytenr;
8773         u64 disk_num_bytes;
8774         u64 extent_num_bytes;
8775         u64 extent_flags;
8776         u64 extent_gen;
8777         u32 item_size;
8778         unsigned long end;
8779         unsigned long ptr;
8780         int type;
8781         u64 ref_root;
8782         int found_dbackref = 0;
8783         int err = 0;
8784         int ret;
8785
8786         btrfs_item_key_to_cpu(eb, &fi_key, slot);
8787         fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
8788         file_extent_gen = btrfs_file_extent_generation(eb, fi);
8789
8790         /* Nothing to check for hole and inline data extents */
8791         if (btrfs_file_extent_type(eb, fi) == BTRFS_FILE_EXTENT_INLINE ||
8792             btrfs_file_extent_disk_bytenr(eb, fi) == 0)
8793                 return 0;
8794
8795         disk_bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
8796         disk_num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
8797         extent_num_bytes = btrfs_file_extent_num_bytes(eb, fi);
8798
8799         /* Check unaligned disk_num_bytes and num_bytes */
8800         if (!IS_ALIGNED(disk_num_bytes, root->sectorsize)) {
8801                 error(
8802 "file extent [%llu, %llu] has unaligned disk num bytes: %llu, should be aligned to %u",
8803                         fi_key.objectid, fi_key.offset, disk_num_bytes,
8804                         root->sectorsize);
8805                 err |= BYTES_UNALIGNED;
8806         } else {
8807                 data_bytes_allocated += disk_num_bytes;
8808         }
8809         if (!IS_ALIGNED(extent_num_bytes, root->sectorsize)) {
8810                 error(
8811 "file extent [%llu, %llu] has unaligned num bytes: %llu, should be aligned to %u",
8812                         fi_key.objectid, fi_key.offset, extent_num_bytes,
8813                         root->sectorsize);
8814                 err |= BYTES_UNALIGNED;
8815         } else {
8816                 data_bytes_referenced += extent_num_bytes;
8817         }
8818         owner = btrfs_header_owner(eb);
8819
8820         /* Check the extent item of the file extent in extent tree */
8821         btrfs_init_path(&path);
8822         dbref_key.objectid = btrfs_file_extent_disk_bytenr(eb, fi);
8823         dbref_key.type = BTRFS_EXTENT_ITEM_KEY;
8824         dbref_key.offset = btrfs_file_extent_disk_num_bytes(eb, fi);
8825
8826         ret = btrfs_search_slot(NULL, extent_root, &dbref_key, &path, 0, 0);
8827         if (ret) {
8828                 err |= BACKREF_MISSING;
8829                 goto error;
8830         }
8831
8832         leaf = path.nodes[0];
8833         slot = path.slots[0];
8834         ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
8835
8836         extent_flags = btrfs_extent_flags(leaf, ei);
8837         extent_gen = btrfs_extent_generation(leaf, ei);
8838
8839         if (!(extent_flags & BTRFS_EXTENT_FLAG_DATA)) {
8840                 error(
8841                     "extent[%llu %llu] backref type mismatch, wanted bit: %llx",
8842                     disk_bytenr, disk_num_bytes,
8843                     BTRFS_EXTENT_FLAG_DATA);
8844                 err |= BACKREF_MISMATCH;
8845         }
8846
8847         if (file_extent_gen < extent_gen) {
8848                 error(
8849 "extent[%llu %llu] backref generation mismatch, wanted: <=%llu, have: %llu",
8850                         disk_bytenr, disk_num_bytes, file_extent_gen,
8851                         extent_gen);
8852                 err |= BACKREF_MISMATCH;
8853         }
8854
8855         /* Check data backref inside that extent item */
8856         item_size = btrfs_item_size_nr(leaf, path.slots[0]);
8857         iref = (struct btrfs_extent_inline_ref *)(ei + 1);
8858         ptr = (unsigned long)iref;
8859         end = (unsigned long)ei + item_size;
8860         while (ptr < end) {
8861                 iref = (struct btrfs_extent_inline_ref *)ptr;
8862                 type = btrfs_extent_inline_ref_type(leaf, iref);
8863                 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
8864
8865                 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
8866                         ref_root = btrfs_extent_data_ref_root(leaf, dref);
8867                         if (ref_root == owner || ref_root == root->objectid)
8868                                 found_dbackref = 1;
8869                 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
8870                         found_dbackref = !check_tree_block_ref(root, NULL,
8871                                 btrfs_extent_inline_ref_offset(leaf, iref),
8872                                 0, owner);
8873                 }
8874
8875                 if (found_dbackref)
8876                         break;
8877                 ptr += btrfs_extent_inline_ref_size(type);
8878         }
8879
8880         /* Didn't found inlined data backref, try EXTENT_DATA_REF_KEY */
8881         if (!found_dbackref) {
8882                 btrfs_release_path(&path);
8883
8884                 btrfs_init_path(&path);
8885                 dbref_key.objectid = btrfs_file_extent_disk_bytenr(eb, fi);
8886                 dbref_key.type = BTRFS_EXTENT_DATA_REF_KEY;
8887                 dbref_key.offset = hash_extent_data_ref(root->objectid,
8888                                 fi_key.objectid, fi_key.offset);
8889
8890                 ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
8891                                         &dbref_key, &path, 0, 0);
8892                 if (!ret)
8893                         found_dbackref = 1;
8894         }
8895
8896         if (!found_dbackref)
8897                 err |= BACKREF_MISSING;
8898 error:
8899         btrfs_release_path(&path);
8900         if (err & BACKREF_MISSING) {
8901                 error("data extent[%llu %llu] backref lost",
8902                       disk_bytenr, disk_num_bytes);
8903         }
8904         return err;
8905 }
8906
8907 /*
8908  * Get real tree block level for the case like shared block
8909  * Return >= 0 as tree level
8910  * Return <0 for error
8911  */
8912 static int query_tree_block_level(struct btrfs_fs_info *fs_info, u64 bytenr)
8913 {
8914         struct extent_buffer *eb;
8915         struct btrfs_path path;
8916         struct btrfs_key key;
8917         struct btrfs_extent_item *ei;
8918         u64 flags;
8919         u64 transid;
8920         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
8921         u8 backref_level;
8922         u8 header_level;
8923         int ret;
8924
8925         /* Search extent tree for extent generation and level */
8926         key.objectid = bytenr;
8927         key.type = BTRFS_METADATA_ITEM_KEY;
8928         key.offset = (u64)-1;
8929
8930         btrfs_init_path(&path);
8931         ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, &path, 0, 0);
8932         if (ret < 0)
8933                 goto release_out;
8934         ret = btrfs_previous_extent_item(fs_info->extent_root, &path, bytenr);
8935         if (ret < 0)
8936                 goto release_out;
8937         if (ret > 0) {
8938                 ret = -ENOENT;
8939                 goto release_out;
8940         }
8941
8942         btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
8943         ei = btrfs_item_ptr(path.nodes[0], path.slots[0],
8944                             struct btrfs_extent_item);
8945         flags = btrfs_extent_flags(path.nodes[0], ei);
8946         if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
8947                 ret = -ENOENT;
8948                 goto release_out;
8949         }
8950
8951         /* Get transid for later read_tree_block() check */
8952         transid = btrfs_extent_generation(path.nodes[0], ei);
8953
8954         /* Get backref level as one source */
8955         if (key.type == BTRFS_METADATA_ITEM_KEY) {
8956                 backref_level = key.offset;
8957         } else {
8958                 struct btrfs_tree_block_info *info;
8959
8960                 info = (struct btrfs_tree_block_info *)(ei + 1);
8961                 backref_level = btrfs_tree_block_level(path.nodes[0], info);
8962         }
8963         btrfs_release_path(&path);
8964
8965         /* Get level from tree block as an alternative source */
8966         eb = read_tree_block_fs_info(fs_info, bytenr, nodesize, transid);
8967         if (!extent_buffer_uptodate(eb)) {
8968                 free_extent_buffer(eb);
8969                 return -EIO;
8970         }
8971         header_level = btrfs_header_level(eb);
8972         free_extent_buffer(eb);
8973
8974         if (header_level != backref_level)
8975                 return -EIO;
8976         return header_level;
8977
8978 release_out:
8979         btrfs_release_path(&path);
8980         return ret;
8981 }
8982
8983 /*
8984  * Check if a tree block backref is valid (points to a valid tree block)
8985  * if level == -1, level will be resolved
8986  * Return >0 for any error found and print error message
8987  */
8988 static int check_tree_block_backref(struct btrfs_fs_info *fs_info, u64 root_id,
8989                                     u64 bytenr, int level)
8990 {
8991         struct btrfs_root *root;
8992         struct btrfs_key key;
8993         struct btrfs_path path;
8994         struct extent_buffer *eb;
8995         struct extent_buffer *node;
8996         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
8997         int err = 0;
8998         int ret;
8999
9000         /* Query level for level == -1 special case */
9001         if (level == -1)
9002                 level = query_tree_block_level(fs_info, bytenr);
9003         if (level < 0) {
9004                 err |= REFERENCER_MISSING;
9005                 goto out;
9006         }
9007
9008         key.objectid = root_id;
9009         key.type = BTRFS_ROOT_ITEM_KEY;
9010         key.offset = (u64)-1;
9011
9012         root = btrfs_read_fs_root(fs_info, &key);
9013         if (IS_ERR(root)) {
9014                 err |= REFERENCER_MISSING;
9015                 goto out;
9016         }
9017
9018         /* Read out the tree block to get item/node key */
9019         eb = read_tree_block(root, bytenr, root->nodesize, 0);
9020         if (!extent_buffer_uptodate(eb)) {
9021                 err |= REFERENCER_MISSING;
9022                 free_extent_buffer(eb);
9023                 goto out;
9024         }
9025
9026         /* Empty tree, no need to check key */
9027         if (!btrfs_header_nritems(eb) && !level) {
9028                 free_extent_buffer(eb);
9029                 goto out;
9030         }
9031
9032         if (level)
9033                 btrfs_node_key_to_cpu(eb, &key, 0);
9034         else
9035                 btrfs_item_key_to_cpu(eb, &key, 0);
9036
9037         free_extent_buffer(eb);
9038
9039         btrfs_init_path(&path);
9040         path.lowest_level = level;
9041         /* Search with the first key, to ensure we can reach it */
9042         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
9043         if (ret < 0) {
9044                 err |= REFERENCER_MISSING;
9045                 goto release_out;
9046         }
9047
9048         node = path.nodes[level];
9049         if (btrfs_header_bytenr(node) != bytenr) {
9050                 error(
9051         "extent [%llu %d] referencer bytenr mismatch, wanted: %llu, have: %llu",
9052                         bytenr, nodesize, bytenr,
9053                         btrfs_header_bytenr(node));
9054                 err |= REFERENCER_MISMATCH;
9055         }
9056         if (btrfs_header_level(node) != level) {
9057                 error(
9058         "extent [%llu %d] referencer level mismatch, wanted: %d, have: %d",
9059                         bytenr, nodesize, level,
9060                         btrfs_header_level(node));
9061                 err |= REFERENCER_MISMATCH;
9062         }
9063
9064 release_out:
9065         btrfs_release_path(&path);
9066 out:
9067         if (err & REFERENCER_MISSING) {
9068                 if (level < 0)
9069                         error("extent [%llu %d] lost referencer (owner: %llu)",
9070                                 bytenr, nodesize, root_id);
9071                 else
9072                         error(
9073                 "extent [%llu %d] lost referencer (owner: %llu, level: %u)",
9074                                 bytenr, nodesize, root_id, level);
9075         }
9076
9077         return err;
9078 }
9079
9080 /*
9081  * Check referencer for shared block backref
9082  * If level == -1, this function will resolve the level.
9083  */
9084 static int check_shared_block_backref(struct btrfs_fs_info *fs_info,
9085                                      u64 parent, u64 bytenr, int level)
9086 {
9087         struct extent_buffer *eb;
9088         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
9089         u32 nr;
9090         int found_parent = 0;
9091         int i;
9092
9093         eb = read_tree_block_fs_info(fs_info, parent, nodesize, 0);
9094         if (!extent_buffer_uptodate(eb))
9095                 goto out;
9096
9097         if (level == -1)
9098                 level = query_tree_block_level(fs_info, bytenr);
9099         if (level < 0)
9100                 goto out;
9101
9102         if (level + 1 != btrfs_header_level(eb))
9103                 goto out;
9104
9105         nr = btrfs_header_nritems(eb);
9106         for (i = 0; i < nr; i++) {
9107                 if (bytenr == btrfs_node_blockptr(eb, i)) {
9108                         found_parent = 1;
9109                         break;
9110                 }
9111         }
9112 out:
9113         free_extent_buffer(eb);
9114         if (!found_parent) {
9115                 error(
9116         "shared extent[%llu %u] lost its parent (parent: %llu, level: %u)",
9117                         bytenr, nodesize, parent, level);
9118                 return REFERENCER_MISSING;
9119         }
9120         return 0;
9121 }
9122
9123 /*
9124  * Check referencer for normal (inlined) data ref
9125  * If len == 0, it will be resolved by searching in extent tree
9126  */
9127 static int check_extent_data_backref(struct btrfs_fs_info *fs_info,
9128                                      u64 root_id, u64 objectid, u64 offset,
9129                                      u64 bytenr, u64 len, u32 count)
9130 {
9131         struct btrfs_root *root;
9132         struct btrfs_root *extent_root = fs_info->extent_root;
9133         struct btrfs_key key;
9134         struct btrfs_path path;
9135         struct extent_buffer *leaf;
9136         struct btrfs_file_extent_item *fi;
9137         u32 found_count = 0;
9138         int slot;
9139         int ret = 0;
9140
9141         if (!len) {
9142                 key.objectid = bytenr;
9143                 key.type = BTRFS_EXTENT_ITEM_KEY;
9144                 key.offset = (u64)-1;
9145
9146                 btrfs_init_path(&path);
9147                 ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
9148                 if (ret < 0)
9149                         goto out;
9150                 ret = btrfs_previous_extent_item(extent_root, &path, bytenr);
9151                 if (ret)
9152                         goto out;
9153                 btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
9154                 if (key.objectid != bytenr ||
9155                     key.type != BTRFS_EXTENT_ITEM_KEY)
9156                         goto out;
9157                 len = key.offset;
9158                 btrfs_release_path(&path);
9159         }
9160         key.objectid = root_id;
9161         key.type = BTRFS_ROOT_ITEM_KEY;
9162         key.offset = (u64)-1;
9163         btrfs_init_path(&path);
9164
9165         root = btrfs_read_fs_root(fs_info, &key);
9166         if (IS_ERR(root))
9167                 goto out;
9168
9169         key.objectid = objectid;
9170         key.type = BTRFS_EXTENT_DATA_KEY;
9171         /*
9172          * It can be nasty as data backref offset is
9173          * file offset - file extent offset, which is smaller or
9174          * equal to original backref offset.  The only special case is
9175          * overflow.  So we need to special check and do further search.
9176          */
9177         key.offset = offset & (1ULL << 63) ? 0 : offset;
9178
9179         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
9180         if (ret < 0)
9181                 goto out;
9182
9183         /*
9184          * Search afterwards to get correct one
9185          * NOTE: As we must do a comprehensive check on the data backref to
9186          * make sure the dref count also matches, we must iterate all file
9187          * extents for that inode.
9188          */
9189         while (1) {
9190                 leaf = path.nodes[0];
9191                 slot = path.slots[0];
9192
9193                 btrfs_item_key_to_cpu(leaf, &key, slot);
9194                 if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)
9195                         break;
9196                 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
9197                 /*
9198                  * Except normal disk bytenr and disk num bytes, we still
9199                  * need to do extra check on dbackref offset as
9200                  * dbackref offset = file_offset - file_extent_offset
9201                  */
9202                 if (btrfs_file_extent_disk_bytenr(leaf, fi) == bytenr &&
9203                     btrfs_file_extent_disk_num_bytes(leaf, fi) == len &&
9204                     (u64)(key.offset - btrfs_file_extent_offset(leaf, fi)) ==
9205                     offset)
9206                         found_count++;
9207
9208                 ret = btrfs_next_item(root, &path);
9209                 if (ret)
9210                         break;
9211         }
9212 out:
9213         btrfs_release_path(&path);
9214         if (found_count != count) {
9215                 error(
9216 "extent[%llu, %llu] referencer count mismatch (root: %llu, owner: %llu, offset: %llu) wanted: %u, have: %u",
9217                         bytenr, len, root_id, objectid, offset, count, found_count);
9218                 return REFERENCER_MISSING;
9219         }
9220         return 0;
9221 }
9222
9223 /*
9224  * Check if the referencer of a shared data backref exists
9225  */
9226 static int check_shared_data_backref(struct btrfs_fs_info *fs_info,
9227                                      u64 parent, u64 bytenr)
9228 {
9229         struct extent_buffer *eb;
9230         struct btrfs_key key;
9231         struct btrfs_file_extent_item *fi;
9232         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
9233         u32 nr;
9234         int found_parent = 0;
9235         int i;
9236
9237         eb = read_tree_block_fs_info(fs_info, parent, nodesize, 0);
9238         if (!extent_buffer_uptodate(eb))
9239                 goto out;
9240
9241         nr = btrfs_header_nritems(eb);
9242         for (i = 0; i < nr; i++) {
9243                 btrfs_item_key_to_cpu(eb, &key, i);
9244                 if (key.type != BTRFS_EXTENT_DATA_KEY)
9245                         continue;
9246
9247                 fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
9248                 if (btrfs_file_extent_type(eb, fi) == BTRFS_FILE_EXTENT_INLINE)
9249                         continue;
9250
9251                 if (btrfs_file_extent_disk_bytenr(eb, fi) == bytenr) {
9252                         found_parent = 1;
9253                         break;
9254                 }
9255         }
9256
9257 out:
9258         free_extent_buffer(eb);
9259         if (!found_parent) {
9260                 error("shared extent %llu referencer lost (parent: %llu)",
9261                         bytenr, parent);
9262                 return REFERENCER_MISSING;
9263         }
9264         return 0;
9265 }
9266
9267 /*
9268  * This function will check a given extent item, including its backref and
9269  * itself (like crossing stripe boundary and type)
9270  *
9271  * Since we don't use extent_record anymore, introduce new error bit
9272  */
9273 static int check_extent_item(struct btrfs_fs_info *fs_info,
9274                              struct extent_buffer *eb, int slot)
9275 {
9276         struct btrfs_extent_item *ei;
9277         struct btrfs_extent_inline_ref *iref;
9278         struct btrfs_extent_data_ref *dref;
9279         unsigned long end;
9280         unsigned long ptr;
9281         int type;
9282         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
9283         u32 item_size = btrfs_item_size_nr(eb, slot);
9284         u64 flags;
9285         u64 offset;
9286         int metadata = 0;
9287         int level;
9288         struct btrfs_key key;
9289         int ret;
9290         int err = 0;
9291
9292         btrfs_item_key_to_cpu(eb, &key, slot);
9293         if (key.type == BTRFS_EXTENT_ITEM_KEY)
9294                 bytes_used += key.offset;
9295         else
9296                 bytes_used += nodesize;
9297
9298         if (item_size < sizeof(*ei)) {
9299                 /*
9300                  * COMPAT_EXTENT_TREE_V0 case, but it's already a super
9301                  * old thing when on disk format is still un-determined.
9302                  * No need to care about it anymore
9303                  */
9304                 error("unsupported COMPAT_EXTENT_TREE_V0 detected");
9305                 return -ENOTTY;
9306         }
9307
9308         ei = btrfs_item_ptr(eb, slot, struct btrfs_extent_item);
9309         flags = btrfs_extent_flags(eb, ei);
9310
9311         if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
9312                 metadata = 1;
9313         if (metadata && check_crossing_stripes(global_info, key.objectid,
9314                                                eb->len)) {
9315                 error("bad metadata [%llu, %llu) crossing stripe boundary",
9316                       key.objectid, key.objectid + nodesize);
9317                 err |= CROSSING_STRIPE_BOUNDARY;
9318         }
9319
9320         ptr = (unsigned long)(ei + 1);
9321
9322         if (metadata && key.type == BTRFS_EXTENT_ITEM_KEY) {
9323                 /* Old EXTENT_ITEM metadata */
9324                 struct btrfs_tree_block_info *info;
9325
9326                 info = (struct btrfs_tree_block_info *)ptr;
9327                 level = btrfs_tree_block_level(eb, info);
9328                 ptr += sizeof(struct btrfs_tree_block_info);
9329         } else {
9330                 /* New METADATA_ITEM */
9331                 level = key.offset;
9332         }
9333         end = (unsigned long)ei + item_size;
9334
9335         if (ptr >= end) {
9336                 err |= ITEM_SIZE_MISMATCH;
9337                 goto out;
9338         }
9339
9340         /* Now check every backref in this extent item */
9341 next:
9342         iref = (struct btrfs_extent_inline_ref *)ptr;
9343         type = btrfs_extent_inline_ref_type(eb, iref);
9344         offset = btrfs_extent_inline_ref_offset(eb, iref);
9345         switch (type) {
9346         case BTRFS_TREE_BLOCK_REF_KEY:
9347                 ret = check_tree_block_backref(fs_info, offset, key.objectid,
9348                                                level);
9349                 err |= ret;
9350                 break;
9351         case BTRFS_SHARED_BLOCK_REF_KEY:
9352                 ret = check_shared_block_backref(fs_info, offset, key.objectid,
9353                                                  level);
9354                 err |= ret;
9355                 break;
9356         case BTRFS_EXTENT_DATA_REF_KEY:
9357                 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
9358                 ret = check_extent_data_backref(fs_info,
9359                                 btrfs_extent_data_ref_root(eb, dref),
9360                                 btrfs_extent_data_ref_objectid(eb, dref),
9361                                 btrfs_extent_data_ref_offset(eb, dref),
9362                                 key.objectid, key.offset,
9363                                 btrfs_extent_data_ref_count(eb, dref));
9364                 err |= ret;
9365                 break;
9366         case BTRFS_SHARED_DATA_REF_KEY:
9367                 ret = check_shared_data_backref(fs_info, offset, key.objectid);
9368                 err |= ret;
9369                 break;
9370         default:
9371                 error("extent[%llu %d %llu] has unknown ref type: %d",
9372                         key.objectid, key.type, key.offset, type);
9373                 err |= UNKNOWN_TYPE;
9374                 goto out;
9375         }
9376
9377         ptr += btrfs_extent_inline_ref_size(type);
9378         if (ptr < end)
9379                 goto next;
9380
9381 out:
9382         return err;
9383 }
9384
9385 /*
9386  * Check if a dev extent item is referred correctly by its chunk
9387  */
9388 static int check_dev_extent_item(struct btrfs_fs_info *fs_info,
9389                                  struct extent_buffer *eb, int slot)
9390 {
9391         struct btrfs_root *chunk_root = fs_info->chunk_root;
9392         struct btrfs_dev_extent *ptr;
9393         struct btrfs_path path;
9394         struct btrfs_key chunk_key;
9395         struct btrfs_key devext_key;
9396         struct btrfs_chunk *chunk;
9397         struct extent_buffer *l;
9398         int num_stripes;
9399         u64 length;
9400         int i;
9401         int found_chunk = 0;
9402         int ret;
9403
9404         btrfs_item_key_to_cpu(eb, &devext_key, slot);
9405         ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_extent);
9406         length = btrfs_dev_extent_length(eb, ptr);
9407
9408         chunk_key.objectid = btrfs_dev_extent_chunk_objectid(eb, ptr);
9409         chunk_key.type = BTRFS_CHUNK_ITEM_KEY;
9410         chunk_key.offset = btrfs_dev_extent_chunk_offset(eb, ptr);
9411
9412         btrfs_init_path(&path);
9413         ret = btrfs_search_slot(NULL, chunk_root, &chunk_key, &path, 0, 0);
9414         if (ret)
9415                 goto out;
9416
9417         l = path.nodes[0];
9418         chunk = btrfs_item_ptr(l, path.slots[0], struct btrfs_chunk);
9419         if (btrfs_chunk_length(l, chunk) != length)
9420                 goto out;
9421
9422         num_stripes = btrfs_chunk_num_stripes(l, chunk);
9423         for (i = 0; i < num_stripes; i++) {
9424                 u64 devid = btrfs_stripe_devid_nr(l, chunk, i);
9425                 u64 offset = btrfs_stripe_offset_nr(l, chunk, i);
9426
9427                 if (devid == devext_key.objectid &&
9428                     offset == devext_key.offset) {
9429                         found_chunk = 1;
9430                         break;
9431                 }
9432         }
9433 out:
9434         btrfs_release_path(&path);
9435         if (!found_chunk) {
9436                 error(
9437                 "device extent[%llu, %llu, %llu] did not find the related chunk",
9438                         devext_key.objectid, devext_key.offset, length);
9439                 return REFERENCER_MISSING;
9440         }
9441         return 0;
9442 }
9443
9444 /*
9445  * Check if the used space is correct with the dev item
9446  */
9447 static int check_dev_item(struct btrfs_fs_info *fs_info,
9448                           struct extent_buffer *eb, int slot)
9449 {
9450         struct btrfs_root *dev_root = fs_info->dev_root;
9451         struct btrfs_dev_item *dev_item;
9452         struct btrfs_path path;
9453         struct btrfs_key key;
9454         struct btrfs_dev_extent *ptr;
9455         u64 dev_id;
9456         u64 used;
9457         u64 total = 0;
9458         int ret;
9459
9460         dev_item = btrfs_item_ptr(eb, slot, struct btrfs_dev_item);
9461         dev_id = btrfs_device_id(eb, dev_item);
9462         used = btrfs_device_bytes_used(eb, dev_item);
9463
9464         key.objectid = dev_id;
9465         key.type = BTRFS_DEV_EXTENT_KEY;
9466         key.offset = 0;
9467
9468         btrfs_init_path(&path);
9469         ret = btrfs_search_slot(NULL, dev_root, &key, &path, 0, 0);
9470         if (ret < 0) {
9471                 btrfs_item_key_to_cpu(eb, &key, slot);
9472                 error("cannot find any related dev extent for dev[%llu, %u, %llu]",
9473                         key.objectid, key.type, key.offset);
9474                 btrfs_release_path(&path);
9475                 return REFERENCER_MISSING;
9476         }
9477
9478         /* Iterate dev_extents to calculate the used space of a device */
9479         while (1) {
9480                 btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
9481
9482                 if (key.objectid > dev_id)
9483                         break;
9484                 if (key.type != BTRFS_DEV_EXTENT_KEY || key.objectid != dev_id)
9485                         goto next;
9486
9487                 ptr = btrfs_item_ptr(path.nodes[0], path.slots[0],
9488                                      struct btrfs_dev_extent);
9489                 total += btrfs_dev_extent_length(path.nodes[0], ptr);
9490 next:
9491                 ret = btrfs_next_item(dev_root, &path);
9492                 if (ret)
9493                         break;
9494         }
9495         btrfs_release_path(&path);
9496
9497         if (used != total) {
9498                 btrfs_item_key_to_cpu(eb, &key, slot);
9499                 error(
9500 "Dev extent's total-byte %llu is not equal to bytes-used %llu in dev[%llu, %u, %llu]",
9501                         total, used, BTRFS_ROOT_TREE_OBJECTID,
9502                         BTRFS_DEV_EXTENT_KEY, dev_id);
9503                 return ACCOUNTING_MISMATCH;
9504         }
9505         return 0;
9506 }
9507
9508 /*
9509  * Check a block group item with its referener (chunk) and its used space
9510  * with extent/metadata item
9511  */
9512 static int check_block_group_item(struct btrfs_fs_info *fs_info,
9513                                   struct extent_buffer *eb, int slot)
9514 {
9515         struct btrfs_root *extent_root = fs_info->extent_root;
9516         struct btrfs_root *chunk_root = fs_info->chunk_root;
9517         struct btrfs_block_group_item *bi;
9518         struct btrfs_block_group_item bg_item;
9519         struct btrfs_path path;
9520         struct btrfs_key bg_key;
9521         struct btrfs_key chunk_key;
9522         struct btrfs_key extent_key;
9523         struct btrfs_chunk *chunk;
9524         struct extent_buffer *leaf;
9525         struct btrfs_extent_item *ei;
9526         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
9527         u64 flags;
9528         u64 bg_flags;
9529         u64 used;
9530         u64 total = 0;
9531         int ret;
9532         int err = 0;
9533
9534         btrfs_item_key_to_cpu(eb, &bg_key, slot);
9535         bi = btrfs_item_ptr(eb, slot, struct btrfs_block_group_item);
9536         read_extent_buffer(eb, &bg_item, (unsigned long)bi, sizeof(bg_item));
9537         used = btrfs_block_group_used(&bg_item);
9538         bg_flags = btrfs_block_group_flags(&bg_item);
9539
9540         chunk_key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
9541         chunk_key.type = BTRFS_CHUNK_ITEM_KEY;
9542         chunk_key.offset = bg_key.objectid;
9543
9544         btrfs_init_path(&path);
9545         /* Search for the referencer chunk */
9546         ret = btrfs_search_slot(NULL, chunk_root, &chunk_key, &path, 0, 0);
9547         if (ret) {
9548                 error(
9549                 "block group[%llu %llu] did not find the related chunk item",
9550                         bg_key.objectid, bg_key.offset);
9551                 err |= REFERENCER_MISSING;
9552         } else {
9553                 chunk = btrfs_item_ptr(path.nodes[0], path.slots[0],
9554                                         struct btrfs_chunk);
9555                 if (btrfs_chunk_length(path.nodes[0], chunk) !=
9556                                                 bg_key.offset) {
9557                         error(
9558         "block group[%llu %llu] related chunk item length does not match",
9559                                 bg_key.objectid, bg_key.offset);
9560                         err |= REFERENCER_MISMATCH;
9561                 }
9562         }
9563         btrfs_release_path(&path);
9564
9565         /* Search from the block group bytenr */
9566         extent_key.objectid = bg_key.objectid;
9567         extent_key.type = 0;
9568         extent_key.offset = 0;
9569
9570         btrfs_init_path(&path);
9571         ret = btrfs_search_slot(NULL, extent_root, &extent_key, &path, 0, 0);
9572         if (ret < 0)
9573                 goto out;
9574
9575         /* Iterate extent tree to account used space */
9576         while (1) {
9577                 leaf = path.nodes[0];
9578                 btrfs_item_key_to_cpu(leaf, &extent_key, path.slots[0]);
9579                 if (extent_key.objectid >= bg_key.objectid + bg_key.offset)
9580                         break;
9581
9582                 if (extent_key.type != BTRFS_METADATA_ITEM_KEY &&
9583                     extent_key.type != BTRFS_EXTENT_ITEM_KEY)
9584                         goto next;
9585                 if (extent_key.objectid < bg_key.objectid)
9586                         goto next;
9587
9588                 if (extent_key.type == BTRFS_METADATA_ITEM_KEY)
9589                         total += nodesize;
9590                 else
9591                         total += extent_key.offset;
9592
9593                 ei = btrfs_item_ptr(leaf, path.slots[0],
9594                                     struct btrfs_extent_item);
9595                 flags = btrfs_extent_flags(leaf, ei);
9596                 if (flags & BTRFS_EXTENT_FLAG_DATA) {
9597                         if (!(bg_flags & BTRFS_BLOCK_GROUP_DATA)) {
9598                                 error(
9599                         "bad extent[%llu, %llu) type mismatch with chunk",
9600                                         extent_key.objectid,
9601                                         extent_key.objectid + extent_key.offset);
9602                                 err |= CHUNK_TYPE_MISMATCH;
9603                         }
9604                 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
9605                         if (!(bg_flags & (BTRFS_BLOCK_GROUP_SYSTEM |
9606                                     BTRFS_BLOCK_GROUP_METADATA))) {
9607                                 error(
9608                         "bad extent[%llu, %llu) type mismatch with chunk",
9609                                         extent_key.objectid,
9610                                         extent_key.objectid + nodesize);
9611                                 err |= CHUNK_TYPE_MISMATCH;
9612                         }
9613                 }
9614 next:
9615                 ret = btrfs_next_item(extent_root, &path);
9616                 if (ret)
9617                         break;
9618         }
9619
9620 out:
9621         btrfs_release_path(&path);
9622
9623         if (total != used) {
9624                 error(
9625                 "block group[%llu %llu] used %llu but extent items used %llu",
9626                         bg_key.objectid, bg_key.offset, used, total);
9627                 err |= ACCOUNTING_MISMATCH;
9628         }
9629         return err;
9630 }
9631
9632 /*
9633  * Check a chunk item.
9634  * Including checking all referred dev_extents and block group
9635  */
9636 static int check_chunk_item(struct btrfs_fs_info *fs_info,
9637                             struct extent_buffer *eb, int slot)
9638 {
9639         struct btrfs_root *extent_root = fs_info->extent_root;
9640         struct btrfs_root *dev_root = fs_info->dev_root;
9641         struct btrfs_path path;
9642         struct btrfs_key chunk_key;
9643         struct btrfs_key bg_key;
9644         struct btrfs_key devext_key;
9645         struct btrfs_chunk *chunk;
9646         struct extent_buffer *leaf;
9647         struct btrfs_block_group_item *bi;
9648         struct btrfs_block_group_item bg_item;
9649         struct btrfs_dev_extent *ptr;
9650         u32 sectorsize = btrfs_super_sectorsize(fs_info->super_copy);
9651         u64 length;
9652         u64 chunk_end;
9653         u64 type;
9654         u64 profile;
9655         int num_stripes;
9656         u64 offset;
9657         u64 objectid;
9658         int i;
9659         int ret;
9660         int err = 0;
9661
9662         btrfs_item_key_to_cpu(eb, &chunk_key, slot);
9663         chunk = btrfs_item_ptr(eb, slot, struct btrfs_chunk);
9664         length = btrfs_chunk_length(eb, chunk);
9665         chunk_end = chunk_key.offset + length;
9666         if (!IS_ALIGNED(length, sectorsize)) {
9667                 error("chunk[%llu %llu) not aligned to %u",
9668                         chunk_key.offset, chunk_end, sectorsize);
9669                 err |= BYTES_UNALIGNED;
9670                 goto out;
9671         }
9672
9673         type = btrfs_chunk_type(eb, chunk);
9674         profile = type & BTRFS_BLOCK_GROUP_PROFILE_MASK;
9675         if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
9676                 error("chunk[%llu %llu) has no chunk type",
9677                         chunk_key.offset, chunk_end);
9678                 err |= UNKNOWN_TYPE;
9679         }
9680         if (profile && (profile & (profile - 1))) {
9681                 error("chunk[%llu %llu) multiple profiles detected: %llx",
9682                         chunk_key.offset, chunk_end, profile);
9683                 err |= UNKNOWN_TYPE;
9684         }
9685
9686         bg_key.objectid = chunk_key.offset;
9687         bg_key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
9688         bg_key.offset = length;
9689
9690         btrfs_init_path(&path);
9691         ret = btrfs_search_slot(NULL, extent_root, &bg_key, &path, 0, 0);
9692         if (ret) {
9693                 error(
9694                 "chunk[%llu %llu) did not find the related block group item",
9695                         chunk_key.offset, chunk_end);
9696                 err |= REFERENCER_MISSING;
9697         } else{
9698                 leaf = path.nodes[0];
9699                 bi = btrfs_item_ptr(leaf, path.slots[0],
9700                                     struct btrfs_block_group_item);
9701                 read_extent_buffer(leaf, &bg_item, (unsigned long)bi,
9702                                    sizeof(bg_item));
9703                 if (btrfs_block_group_flags(&bg_item) != type) {
9704                         error(
9705 "chunk[%llu %llu) related block group item flags mismatch, wanted: %llu, have: %llu",
9706                                 chunk_key.offset, chunk_end, type,
9707                                 btrfs_block_group_flags(&bg_item));
9708                         err |= REFERENCER_MISSING;
9709                 }
9710         }
9711
9712         num_stripes = btrfs_chunk_num_stripes(eb, chunk);
9713         for (i = 0; i < num_stripes; i++) {
9714                 btrfs_release_path(&path);
9715                 btrfs_init_path(&path);
9716                 devext_key.objectid = btrfs_stripe_devid_nr(eb, chunk, i);
9717                 devext_key.type = BTRFS_DEV_EXTENT_KEY;
9718                 devext_key.offset = btrfs_stripe_offset_nr(eb, chunk, i);
9719
9720                 ret = btrfs_search_slot(NULL, dev_root, &devext_key, &path,
9721                                         0, 0);
9722                 if (ret)
9723                         goto not_match_dev;
9724
9725                 leaf = path.nodes[0];
9726                 ptr = btrfs_item_ptr(leaf, path.slots[0],
9727                                      struct btrfs_dev_extent);
9728                 objectid = btrfs_dev_extent_chunk_objectid(leaf, ptr);
9729                 offset = btrfs_dev_extent_chunk_offset(leaf, ptr);
9730                 if (objectid != chunk_key.objectid ||
9731                     offset != chunk_key.offset ||
9732                     btrfs_dev_extent_length(leaf, ptr) != length)
9733                         goto not_match_dev;
9734                 continue;
9735 not_match_dev:
9736                 err |= BACKREF_MISSING;
9737                 error(
9738                 "chunk[%llu %llu) stripe %d did not find the related dev extent",
9739                         chunk_key.objectid, chunk_end, i);
9740                 continue;
9741         }
9742         btrfs_release_path(&path);
9743 out:
9744         return err;
9745 }
9746
9747 /*
9748  * Main entry function to check known items and update related accounting info
9749  */
9750 static int check_leaf_items(struct btrfs_root *root, struct extent_buffer *eb)
9751 {
9752         struct btrfs_fs_info *fs_info = root->fs_info;
9753         struct btrfs_key key;
9754         int slot = 0;
9755         int type;
9756         struct btrfs_extent_data_ref *dref;
9757         int ret;
9758         int err = 0;
9759
9760 next:
9761         btrfs_item_key_to_cpu(eb, &key, slot);
9762         type = key.type;
9763
9764         switch (type) {
9765         case BTRFS_EXTENT_DATA_KEY:
9766                 ret = check_extent_data_item(root, eb, slot);
9767                 err |= ret;
9768                 break;
9769         case BTRFS_BLOCK_GROUP_ITEM_KEY:
9770                 ret = check_block_group_item(fs_info, eb, slot);
9771                 err |= ret;
9772                 break;
9773         case BTRFS_DEV_ITEM_KEY:
9774                 ret = check_dev_item(fs_info, eb, slot);
9775                 err |= ret;
9776                 break;
9777         case BTRFS_CHUNK_ITEM_KEY:
9778                 ret = check_chunk_item(fs_info, eb, slot);
9779                 err |= ret;
9780                 break;
9781         case BTRFS_DEV_EXTENT_KEY:
9782                 ret = check_dev_extent_item(fs_info, eb, slot);
9783                 err |= ret;
9784                 break;
9785         case BTRFS_EXTENT_ITEM_KEY:
9786         case BTRFS_METADATA_ITEM_KEY:
9787                 ret = check_extent_item(fs_info, eb, slot);
9788                 err |= ret;
9789                 break;
9790         case BTRFS_EXTENT_CSUM_KEY:
9791                 total_csum_bytes += btrfs_item_size_nr(eb, slot);
9792                 break;
9793         case BTRFS_TREE_BLOCK_REF_KEY:
9794                 ret = check_tree_block_backref(fs_info, key.offset,
9795                                                key.objectid, -1);
9796                 err |= ret;
9797                 break;
9798         case BTRFS_EXTENT_DATA_REF_KEY:
9799                 dref = btrfs_item_ptr(eb, slot, struct btrfs_extent_data_ref);
9800                 ret = check_extent_data_backref(fs_info,
9801                                 btrfs_extent_data_ref_root(eb, dref),
9802                                 btrfs_extent_data_ref_objectid(eb, dref),
9803                                 btrfs_extent_data_ref_offset(eb, dref),
9804                                 key.objectid, 0,
9805                                 btrfs_extent_data_ref_count(eb, dref));
9806                 err |= ret;
9807                 break;
9808         case BTRFS_SHARED_BLOCK_REF_KEY:
9809                 ret = check_shared_block_backref(fs_info, key.offset,
9810                                                  key.objectid, -1);
9811                 err |= ret;
9812                 break;
9813         case BTRFS_SHARED_DATA_REF_KEY:
9814                 ret = check_shared_data_backref(fs_info, key.offset,
9815                                                 key.objectid);
9816                 err |= ret;
9817                 break;
9818         default:
9819                 break;
9820         }
9821
9822         if (++slot < btrfs_header_nritems(eb))
9823                 goto next;
9824
9825         return err;
9826 }
9827
9828 /*
9829  * Helper function for later fs/subvol tree check.  To determine if a tree
9830  * block should be checked.
9831  * This function will ensure only the direct referencer with lowest rootid to
9832  * check a fs/subvolume tree block.
9833  *
9834  * Backref check at extent tree would detect errors like missing subvolume
9835  * tree, so we can do aggressive check to reduce duplicated checks.
9836  */
9837 static int should_check(struct btrfs_root *root, struct extent_buffer *eb)
9838 {
9839         struct btrfs_root *extent_root = root->fs_info->extent_root;
9840         struct btrfs_key key;
9841         struct btrfs_path path;
9842         struct extent_buffer *leaf;
9843         int slot;
9844         struct btrfs_extent_item *ei;
9845         unsigned long ptr;
9846         unsigned long end;
9847         int type;
9848         u32 item_size;
9849         u64 offset;
9850         struct btrfs_extent_inline_ref *iref;
9851         int ret;
9852
9853         btrfs_init_path(&path);
9854         key.objectid = btrfs_header_bytenr(eb);
9855         key.type = BTRFS_METADATA_ITEM_KEY;
9856         key.offset = (u64)-1;
9857
9858         /*
9859          * Any failure in backref resolving means we can't determine
9860          * whom the tree block belongs to.
9861          * So in that case, we need to check that tree block
9862          */
9863         ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
9864         if (ret < 0)
9865                 goto need_check;
9866
9867         ret = btrfs_previous_extent_item(extent_root, &path,
9868                                          btrfs_header_bytenr(eb));
9869         if (ret)
9870                 goto need_check;
9871
9872         leaf = path.nodes[0];
9873         slot = path.slots[0];
9874         btrfs_item_key_to_cpu(leaf, &key, slot);
9875         ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
9876
9877         if (key.type == BTRFS_METADATA_ITEM_KEY) {
9878                 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
9879         } else {
9880                 struct btrfs_tree_block_info *info;
9881
9882                 info = (struct btrfs_tree_block_info *)(ei + 1);
9883                 iref = (struct btrfs_extent_inline_ref *)(info + 1);
9884         }
9885
9886         item_size = btrfs_item_size_nr(leaf, slot);
9887         ptr = (unsigned long)iref;
9888         end = (unsigned long)ei + item_size;
9889         while (ptr < end) {
9890                 iref = (struct btrfs_extent_inline_ref *)ptr;
9891                 type = btrfs_extent_inline_ref_type(leaf, iref);
9892                 offset = btrfs_extent_inline_ref_offset(leaf, iref);
9893
9894                 /*
9895                  * We only check the tree block if current root is
9896                  * the lowest referencer of it.
9897                  */
9898                 if (type == BTRFS_TREE_BLOCK_REF_KEY &&
9899                     offset < root->objectid) {
9900                         btrfs_release_path(&path);
9901                         return 0;
9902                 }
9903
9904                 ptr += btrfs_extent_inline_ref_size(type);
9905         }
9906         /*
9907          * Normally we should also check keyed tree block ref, but that may be
9908          * very time consuming.  Inlined ref should already make us skip a lot
9909          * of refs now.  So skip search keyed tree block ref.
9910          */
9911
9912 need_check:
9913         btrfs_release_path(&path);
9914         return 1;
9915 }
9916
9917 /*
9918  * Traversal function for tree block. We will do:
9919  * 1) Skip shared fs/subvolume tree blocks
9920  * 2) Update related bytes accounting
9921  * 3) Pre-order traversal
9922  */
9923 static int traverse_tree_block(struct btrfs_root *root,
9924                                 struct extent_buffer *node)
9925 {
9926         struct extent_buffer *eb;
9927         struct btrfs_key key;
9928         struct btrfs_key drop_key;
9929         int level;
9930         u64 nr;
9931         int i;
9932         int err = 0;
9933         int ret;
9934
9935         /*
9936          * Skip shared fs/subvolume tree block, in that case they will
9937          * be checked by referencer with lowest rootid
9938          */
9939         if (is_fstree(root->objectid) && !should_check(root, node))
9940                 return 0;
9941
9942         /* Update bytes accounting */
9943         total_btree_bytes += node->len;
9944         if (fs_root_objectid(btrfs_header_owner(node)))
9945                 total_fs_tree_bytes += node->len;
9946         if (btrfs_header_owner(node) == BTRFS_EXTENT_TREE_OBJECTID)
9947                 total_extent_tree_bytes += node->len;
9948         if (!found_old_backref &&
9949             btrfs_header_owner(node) == BTRFS_TREE_RELOC_OBJECTID &&
9950             btrfs_header_backref_rev(node) == BTRFS_MIXED_BACKREF_REV &&
9951             !btrfs_header_flag(node, BTRFS_HEADER_FLAG_RELOC))
9952                 found_old_backref = 1;
9953
9954         /* pre-order tranversal, check itself first */
9955         level = btrfs_header_level(node);
9956         ret = check_tree_block_ref(root, node, btrfs_header_bytenr(node),
9957                                    btrfs_header_level(node),
9958                                    btrfs_header_owner(node));
9959         err |= ret;
9960         if (err)
9961                 error(
9962         "check %s failed root %llu bytenr %llu level %d, force continue check",
9963                         level ? "node":"leaf", root->objectid,
9964                         btrfs_header_bytenr(node), btrfs_header_level(node));
9965
9966         if (!level) {
9967                 btree_space_waste += btrfs_leaf_free_space(root, node);
9968                 ret = check_leaf_items(root, node);
9969                 err |= ret;
9970                 return err;
9971         }
9972
9973         nr = btrfs_header_nritems(node);
9974         btrfs_disk_key_to_cpu(&drop_key, &root->root_item.drop_progress);
9975         btree_space_waste += (BTRFS_NODEPTRS_PER_BLOCK(root) - nr) *
9976                 sizeof(struct btrfs_key_ptr);
9977
9978         /* Then check all its children */
9979         for (i = 0; i < nr; i++) {
9980                 u64 blocknr = btrfs_node_blockptr(node, i);
9981
9982                 btrfs_node_key_to_cpu(node, &key, i);
9983                 if (level == root->root_item.drop_level &&
9984                     is_dropped_key(&key, &drop_key))
9985                         continue;
9986
9987                 /*
9988                  * As a btrfs tree has most 8 levels (0..7), so it's quite safe
9989                  * to call the function itself.
9990                  */
9991                 eb = read_tree_block(root, blocknr, root->nodesize, 0);
9992                 if (extent_buffer_uptodate(eb)) {
9993                         ret = traverse_tree_block(root, eb);
9994                         err |= ret;
9995                 }
9996                 free_extent_buffer(eb);
9997         }
9998
9999         return err;
10000 }
10001
10002 /*
10003  * Low memory usage version check_chunks_and_extents.
10004  */
10005 static int check_chunks_and_extents_v2(struct btrfs_root *root)
10006 {
10007         struct btrfs_path path;
10008         struct btrfs_key key;
10009         struct btrfs_root *root1;
10010         struct btrfs_root *cur_root;
10011         int err = 0;
10012         int ret;
10013
10014         root1 = root->fs_info->chunk_root;
10015         ret = traverse_tree_block(root1, root1->node);
10016         err |= ret;
10017
10018         root1 = root->fs_info->tree_root;
10019         ret = traverse_tree_block(root1, root1->node);
10020         err |= ret;
10021
10022         btrfs_init_path(&path);
10023         key.objectid = BTRFS_EXTENT_TREE_OBJECTID;
10024         key.offset = 0;
10025         key.type = BTRFS_ROOT_ITEM_KEY;
10026
10027         ret = btrfs_search_slot(NULL, root1, &key, &path, 0, 0);
10028         if (ret) {
10029                 error("cannot find extent treet in tree_root");
10030                 goto out;
10031         }
10032
10033         while (1) {
10034                 btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
10035                 if (key.type != BTRFS_ROOT_ITEM_KEY)
10036                         goto next;
10037                 key.offset = (u64)-1;
10038
10039                 cur_root = btrfs_read_fs_root(root->fs_info, &key);
10040                 if (IS_ERR(cur_root) || !cur_root) {
10041                         error("failed to read tree: %lld", key.objectid);
10042                         goto next;
10043                 }
10044
10045                 ret = traverse_tree_block(cur_root, cur_root->node);
10046                 err |= ret;
10047
10048 next:
10049                 ret = btrfs_next_item(root1, &path);
10050                 if (ret)
10051                         goto out;
10052         }
10053
10054 out:
10055         btrfs_release_path(&path);
10056         return err;
10057 }
10058
10059 static int btrfs_fsck_reinit_root(struct btrfs_trans_handle *trans,
10060                            struct btrfs_root *root, int overwrite)
10061 {
10062         struct extent_buffer *c;
10063         struct extent_buffer *old = root->node;
10064         int level;
10065         int ret;
10066         struct btrfs_disk_key disk_key = {0,0,0};
10067
10068         level = 0;
10069
10070         if (overwrite) {
10071                 c = old;
10072                 extent_buffer_get(c);
10073                 goto init;
10074         }
10075         c = btrfs_alloc_free_block(trans, root,
10076                                    root->nodesize,
10077                                    root->root_key.objectid,
10078                                    &disk_key, level, 0, 0);
10079         if (IS_ERR(c)) {
10080                 c = old;
10081                 extent_buffer_get(c);
10082                 overwrite = 1;
10083         }
10084 init:
10085         memset_extent_buffer(c, 0, 0, sizeof(struct btrfs_header));
10086         btrfs_set_header_level(c, level);
10087         btrfs_set_header_bytenr(c, c->start);
10088         btrfs_set_header_generation(c, trans->transid);
10089         btrfs_set_header_backref_rev(c, BTRFS_MIXED_BACKREF_REV);
10090         btrfs_set_header_owner(c, root->root_key.objectid);
10091
10092         write_extent_buffer(c, root->fs_info->fsid,
10093                             btrfs_header_fsid(), BTRFS_FSID_SIZE);
10094
10095         write_extent_buffer(c, root->fs_info->chunk_tree_uuid,
10096                             btrfs_header_chunk_tree_uuid(c),
10097                             BTRFS_UUID_SIZE);
10098
10099         btrfs_mark_buffer_dirty(c);
10100         /*
10101          * this case can happen in the following case:
10102          *
10103          * 1.overwrite previous root.
10104          *
10105          * 2.reinit reloc data root, this is because we skip pin
10106          * down reloc data tree before which means we can allocate
10107          * same block bytenr here.
10108          */
10109         if (old->start == c->start) {
10110                 btrfs_set_root_generation(&root->root_item,
10111                                           trans->transid);
10112                 root->root_item.level = btrfs_header_level(root->node);
10113                 ret = btrfs_update_root(trans, root->fs_info->tree_root,
10114                                         &root->root_key, &root->root_item);
10115                 if (ret) {
10116                         free_extent_buffer(c);
10117                         return ret;
10118                 }
10119         }
10120         free_extent_buffer(old);
10121         root->node = c;
10122         add_root_to_dirty_list(root);
10123         return 0;
10124 }
10125
10126 static int pin_down_tree_blocks(struct btrfs_fs_info *fs_info,
10127                                 struct extent_buffer *eb, int tree_root)
10128 {
10129         struct extent_buffer *tmp;
10130         struct btrfs_root_item *ri;
10131         struct btrfs_key key;
10132         u64 bytenr;
10133         u32 nodesize;
10134         int level = btrfs_header_level(eb);
10135         int nritems;
10136         int ret;
10137         int i;
10138
10139         /*
10140          * If we have pinned this block before, don't pin it again.
10141          * This can not only avoid forever loop with broken filesystem
10142          * but also give us some speedups.
10143          */
10144         if (test_range_bit(&fs_info->pinned_extents, eb->start,
10145                            eb->start + eb->len - 1, EXTENT_DIRTY, 0))
10146                 return 0;
10147
10148         btrfs_pin_extent(fs_info, eb->start, eb->len);
10149
10150         nodesize = btrfs_super_nodesize(fs_info->super_copy);
10151         nritems = btrfs_header_nritems(eb);
10152         for (i = 0; i < nritems; i++) {
10153                 if (level == 0) {
10154                         btrfs_item_key_to_cpu(eb, &key, i);
10155                         if (key.type != BTRFS_ROOT_ITEM_KEY)
10156                                 continue;
10157                         /* Skip the extent root and reloc roots */
10158                         if (key.objectid == BTRFS_EXTENT_TREE_OBJECTID ||
10159                             key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
10160                             key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
10161                                 continue;
10162                         ri = btrfs_item_ptr(eb, i, struct btrfs_root_item);
10163                         bytenr = btrfs_disk_root_bytenr(eb, ri);
10164
10165                         /*
10166                          * If at any point we start needing the real root we
10167                          * will have to build a stump root for the root we are
10168                          * in, but for now this doesn't actually use the root so
10169                          * just pass in extent_root.
10170                          */
10171                         tmp = read_tree_block(fs_info->extent_root, bytenr,
10172                                               nodesize, 0);
10173                         if (!extent_buffer_uptodate(tmp)) {
10174                                 fprintf(stderr, "Error reading root block\n");
10175                                 return -EIO;
10176                         }
10177                         ret = pin_down_tree_blocks(fs_info, tmp, 0);
10178                         free_extent_buffer(tmp);
10179                         if (ret)
10180                                 return ret;
10181                 } else {
10182                         bytenr = btrfs_node_blockptr(eb, i);
10183
10184                         /* If we aren't the tree root don't read the block */
10185                         if (level == 1 && !tree_root) {
10186                                 btrfs_pin_extent(fs_info, bytenr, nodesize);
10187                                 continue;
10188                         }
10189
10190                         tmp = read_tree_block(fs_info->extent_root, bytenr,
10191                                               nodesize, 0);
10192                         if (!extent_buffer_uptodate(tmp)) {
10193                                 fprintf(stderr, "Error reading tree block\n");
10194                                 return -EIO;
10195                         }
10196                         ret = pin_down_tree_blocks(fs_info, tmp, tree_root);
10197                         free_extent_buffer(tmp);
10198                         if (ret)
10199                                 return ret;
10200                 }
10201         }
10202
10203         return 0;
10204 }
10205
10206 static int pin_metadata_blocks(struct btrfs_fs_info *fs_info)
10207 {
10208         int ret;
10209
10210         ret = pin_down_tree_blocks(fs_info, fs_info->chunk_root->node, 0);
10211         if (ret)
10212                 return ret;
10213
10214         return pin_down_tree_blocks(fs_info, fs_info->tree_root->node, 1);
10215 }
10216
10217 static int reset_block_groups(struct btrfs_fs_info *fs_info)
10218 {
10219         struct btrfs_block_group_cache *cache;
10220         struct btrfs_path path;
10221         struct extent_buffer *leaf;
10222         struct btrfs_chunk *chunk;
10223         struct btrfs_key key;
10224         int ret;
10225         u64 start;
10226
10227         btrfs_init_path(&path);
10228         key.objectid = 0;
10229         key.type = BTRFS_CHUNK_ITEM_KEY;
10230         key.offset = 0;
10231         ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, &path, 0, 0);
10232         if (ret < 0) {
10233                 btrfs_release_path(&path);
10234                 return ret;
10235         }
10236
10237         /*
10238          * We do this in case the block groups were screwed up and had alloc
10239          * bits that aren't actually set on the chunks.  This happens with
10240          * restored images every time and could happen in real life I guess.
10241          */
10242         fs_info->avail_data_alloc_bits = 0;
10243         fs_info->avail_metadata_alloc_bits = 0;
10244         fs_info->avail_system_alloc_bits = 0;
10245
10246         /* First we need to create the in-memory block groups */
10247         while (1) {
10248                 if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
10249                         ret = btrfs_next_leaf(fs_info->chunk_root, &path);
10250                         if (ret < 0) {
10251                                 btrfs_release_path(&path);
10252                                 return ret;
10253                         }
10254                         if (ret) {
10255                                 ret = 0;
10256                                 break;
10257                         }
10258                 }
10259                 leaf = path.nodes[0];
10260                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
10261                 if (key.type != BTRFS_CHUNK_ITEM_KEY) {
10262                         path.slots[0]++;
10263                         continue;
10264                 }
10265
10266                 chunk = btrfs_item_ptr(leaf, path.slots[0], struct btrfs_chunk);
10267                 btrfs_add_block_group(fs_info, 0,
10268                                       btrfs_chunk_type(leaf, chunk),
10269                                       key.objectid, key.offset,
10270                                       btrfs_chunk_length(leaf, chunk));
10271                 set_extent_dirty(&fs_info->free_space_cache, key.offset,
10272                                  key.offset + btrfs_chunk_length(leaf, chunk),
10273                                  GFP_NOFS);
10274                 path.slots[0]++;
10275         }
10276         start = 0;
10277         while (1) {
10278                 cache = btrfs_lookup_first_block_group(fs_info, start);
10279                 if (!cache)
10280                         break;
10281                 cache->cached = 1;
10282                 start = cache->key.objectid + cache->key.offset;
10283         }
10284
10285         btrfs_release_path(&path);
10286         return 0;
10287 }
10288
10289 static int reset_balance(struct btrfs_trans_handle *trans,
10290                          struct btrfs_fs_info *fs_info)
10291 {
10292         struct btrfs_root *root = fs_info->tree_root;
10293         struct btrfs_path path;
10294         struct extent_buffer *leaf;
10295         struct btrfs_key key;
10296         int del_slot, del_nr = 0;
10297         int ret;
10298         int found = 0;
10299
10300         btrfs_init_path(&path);
10301         key.objectid = BTRFS_BALANCE_OBJECTID;
10302         key.type = BTRFS_BALANCE_ITEM_KEY;
10303         key.offset = 0;
10304         ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
10305         if (ret) {
10306                 if (ret > 0)
10307                         ret = 0;
10308                 if (!ret)
10309                         goto reinit_data_reloc;
10310                 else
10311                         goto out;
10312         }
10313
10314         ret = btrfs_del_item(trans, root, &path);
10315         if (ret)
10316                 goto out;
10317         btrfs_release_path(&path);
10318
10319         key.objectid = BTRFS_TREE_RELOC_OBJECTID;
10320         key.type = BTRFS_ROOT_ITEM_KEY;
10321         key.offset = 0;
10322         ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
10323         if (ret < 0)
10324                 goto out;
10325         while (1) {
10326                 if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
10327                         if (!found)
10328                                 break;
10329
10330                         if (del_nr) {
10331                                 ret = btrfs_del_items(trans, root, &path,
10332                                                       del_slot, del_nr);
10333                                 del_nr = 0;
10334                                 if (ret)
10335                                         goto out;
10336                         }
10337                         key.offset++;
10338                         btrfs_release_path(&path);
10339
10340                         found = 0;
10341                         ret = btrfs_search_slot(trans, root, &key, &path,
10342                                                 -1, 1);
10343                         if (ret < 0)
10344                                 goto out;
10345                         continue;
10346                 }
10347                 found = 1;
10348                 leaf = path.nodes[0];
10349                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
10350                 if (key.objectid > BTRFS_TREE_RELOC_OBJECTID)
10351                         break;
10352                 if (key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
10353                         path.slots[0]++;
10354                         continue;
10355                 }
10356                 if (!del_nr) {
10357                         del_slot = path.slots[0];
10358                         del_nr = 1;
10359                 } else {
10360                         del_nr++;
10361                 }
10362                 path.slots[0]++;
10363         }
10364
10365         if (del_nr) {
10366                 ret = btrfs_del_items(trans, root, &path, del_slot, del_nr);
10367                 if (ret)
10368                         goto out;
10369         }
10370         btrfs_release_path(&path);
10371
10372 reinit_data_reloc:
10373         key.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
10374         key.type = BTRFS_ROOT_ITEM_KEY;
10375         key.offset = (u64)-1;
10376         root = btrfs_read_fs_root(fs_info, &key);
10377         if (IS_ERR(root)) {
10378                 fprintf(stderr, "Error reading data reloc tree\n");
10379                 ret = PTR_ERR(root);
10380                 goto out;
10381         }
10382         record_root_in_trans(trans, root);
10383         ret = btrfs_fsck_reinit_root(trans, root, 0);
10384         if (ret)
10385                 goto out;
10386         ret = btrfs_make_root_dir(trans, root, BTRFS_FIRST_FREE_OBJECTID);
10387 out:
10388         btrfs_release_path(&path);
10389         return ret;
10390 }
10391
10392 static int reinit_extent_tree(struct btrfs_trans_handle *trans,
10393                               struct btrfs_fs_info *fs_info)
10394 {
10395         u64 start = 0;
10396         int ret;
10397
10398         /*
10399          * The only reason we don't do this is because right now we're just
10400          * walking the trees we find and pinning down their bytes, we don't look
10401          * at any of the leaves.  In order to do mixed groups we'd have to check
10402          * the leaves of any fs roots and pin down the bytes for any file
10403          * extents we find.  Not hard but why do it if we don't have to?
10404          */
10405         if (btrfs_fs_incompat(fs_info, BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)) {
10406                 fprintf(stderr, "We don't support re-initing the extent tree "
10407                         "for mixed block groups yet, please notify a btrfs "
10408                         "developer you want to do this so they can add this "
10409                         "functionality.\n");
10410                 return -EINVAL;
10411         }
10412
10413         /*
10414          * first we need to walk all of the trees except the extent tree and pin
10415          * down the bytes that are in use so we don't overwrite any existing
10416          * metadata.
10417          */
10418         ret = pin_metadata_blocks(fs_info);
10419         if (ret) {
10420                 fprintf(stderr, "error pinning down used bytes\n");
10421                 return ret;
10422         }
10423
10424         /*
10425          * Need to drop all the block groups since we're going to recreate all
10426          * of them again.
10427          */
10428         btrfs_free_block_groups(fs_info);
10429         ret = reset_block_groups(fs_info);
10430         if (ret) {
10431                 fprintf(stderr, "error resetting the block groups\n");
10432                 return ret;
10433         }
10434
10435         /* Ok we can allocate now, reinit the extent root */
10436         ret = btrfs_fsck_reinit_root(trans, fs_info->extent_root, 0);
10437         if (ret) {
10438                 fprintf(stderr, "extent root initialization failed\n");
10439                 /*
10440                  * When the transaction code is updated we should end the
10441                  * transaction, but for now progs only knows about commit so
10442                  * just return an error.
10443                  */
10444                 return ret;
10445         }
10446
10447         /*
10448          * Now we have all the in-memory block groups setup so we can make
10449          * allocations properly, and the metadata we care about is safe since we
10450          * pinned all of it above.
10451          */
10452         while (1) {
10453                 struct btrfs_block_group_cache *cache;
10454
10455                 cache = btrfs_lookup_first_block_group(fs_info, start);
10456                 if (!cache)
10457                         break;
10458                 start = cache->key.objectid + cache->key.offset;
10459                 ret = btrfs_insert_item(trans, fs_info->extent_root,
10460                                         &cache->key, &cache->item,
10461                                         sizeof(cache->item));
10462                 if (ret) {
10463                         fprintf(stderr, "Error adding block group\n");
10464                         return ret;
10465                 }
10466                 btrfs_extent_post_op(trans, fs_info->extent_root);
10467         }
10468
10469         ret = reset_balance(trans, fs_info);
10470         if (ret)
10471                 fprintf(stderr, "error resetting the pending balance\n");
10472
10473         return ret;
10474 }
10475
10476 static int recow_extent_buffer(struct btrfs_root *root, struct extent_buffer *eb)
10477 {
10478         struct btrfs_path path;
10479         struct btrfs_trans_handle *trans;
10480         struct btrfs_key key;
10481         int ret;
10482
10483         printf("Recowing metadata block %llu\n", eb->start);
10484         key.objectid = btrfs_header_owner(eb);
10485         key.type = BTRFS_ROOT_ITEM_KEY;
10486         key.offset = (u64)-1;
10487
10488         root = btrfs_read_fs_root(root->fs_info, &key);
10489         if (IS_ERR(root)) {
10490                 fprintf(stderr, "Couldn't find owner root %llu\n",
10491                         key.objectid);
10492                 return PTR_ERR(root);
10493         }
10494
10495         trans = btrfs_start_transaction(root, 1);
10496         if (IS_ERR(trans))
10497                 return PTR_ERR(trans);
10498
10499         btrfs_init_path(&path);
10500         path.lowest_level = btrfs_header_level(eb);
10501         if (path.lowest_level)
10502                 btrfs_node_key_to_cpu(eb, &key, 0);
10503         else
10504                 btrfs_item_key_to_cpu(eb, &key, 0);
10505
10506         ret = btrfs_search_slot(trans, root, &key, &path, 0, 1);
10507         btrfs_commit_transaction(trans, root);
10508         btrfs_release_path(&path);
10509         return ret;
10510 }
10511
10512 static int delete_bad_item(struct btrfs_root *root, struct bad_item *bad)
10513 {
10514         struct btrfs_path path;
10515         struct btrfs_trans_handle *trans;
10516         struct btrfs_key key;
10517         int ret;
10518
10519         printf("Deleting bad item [%llu,%u,%llu]\n", bad->key.objectid,
10520                bad->key.type, bad->key.offset);
10521         key.objectid = bad->root_id;
10522         key.type = BTRFS_ROOT_ITEM_KEY;
10523         key.offset = (u64)-1;
10524
10525         root = btrfs_read_fs_root(root->fs_info, &key);
10526         if (IS_ERR(root)) {
10527                 fprintf(stderr, "Couldn't find owner root %llu\n",
10528                         key.objectid);
10529                 return PTR_ERR(root);
10530         }
10531
10532         trans = btrfs_start_transaction(root, 1);
10533         if (IS_ERR(trans))
10534                 return PTR_ERR(trans);
10535
10536         btrfs_init_path(&path);
10537         ret = btrfs_search_slot(trans, root, &bad->key, &path, -1, 1);
10538         if (ret) {
10539                 if (ret > 0)
10540                         ret = 0;
10541                 goto out;
10542         }
10543         ret = btrfs_del_item(trans, root, &path);
10544 out:
10545         btrfs_commit_transaction(trans, root);
10546         btrfs_release_path(&path);
10547         return ret;
10548 }
10549
10550 static int zero_log_tree(struct btrfs_root *root)
10551 {
10552         struct btrfs_trans_handle *trans;
10553         int ret;
10554
10555         trans = btrfs_start_transaction(root, 1);
10556         if (IS_ERR(trans)) {
10557                 ret = PTR_ERR(trans);
10558                 return ret;
10559         }
10560         btrfs_set_super_log_root(root->fs_info->super_copy, 0);
10561         btrfs_set_super_log_root_level(root->fs_info->super_copy, 0);
10562         ret = btrfs_commit_transaction(trans, root);
10563         return ret;
10564 }
10565
10566 static int populate_csum(struct btrfs_trans_handle *trans,
10567                          struct btrfs_root *csum_root, char *buf, u64 start,
10568                          u64 len)
10569 {
10570         u64 offset = 0;
10571         u64 sectorsize;
10572         int ret = 0;
10573
10574         while (offset < len) {
10575                 sectorsize = csum_root->sectorsize;
10576                 ret = read_extent_data(csum_root, buf, start + offset,
10577                                        &sectorsize, 0);
10578                 if (ret)
10579                         break;
10580                 ret = btrfs_csum_file_block(trans, csum_root, start + len,
10581                                             start + offset, buf, sectorsize);
10582                 if (ret)
10583                         break;
10584                 offset += sectorsize;
10585         }
10586         return ret;
10587 }
10588
10589 static int fill_csum_tree_from_one_fs_root(struct btrfs_trans_handle *trans,
10590                                       struct btrfs_root *csum_root,
10591                                       struct btrfs_root *cur_root)
10592 {
10593         struct btrfs_path path;
10594         struct btrfs_key key;
10595         struct extent_buffer *node;
10596         struct btrfs_file_extent_item *fi;
10597         char *buf = NULL;
10598         u64 start = 0;
10599         u64 len = 0;
10600         int slot = 0;
10601         int ret = 0;
10602
10603         buf = malloc(cur_root->fs_info->csum_root->sectorsize);
10604         if (!buf)
10605                 return -ENOMEM;
10606
10607         btrfs_init_path(&path);
10608         key.objectid = 0;
10609         key.offset = 0;
10610         key.type = 0;
10611         ret = btrfs_search_slot(NULL, cur_root, &key, &path, 0, 0);
10612         if (ret < 0)
10613                 goto out;
10614         /* Iterate all regular file extents and fill its csum */
10615         while (1) {
10616                 btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
10617
10618                 if (key.type != BTRFS_EXTENT_DATA_KEY)
10619                         goto next;
10620                 node = path.nodes[0];
10621                 slot = path.slots[0];
10622                 fi = btrfs_item_ptr(node, slot, struct btrfs_file_extent_item);
10623                 if (btrfs_file_extent_type(node, fi) != BTRFS_FILE_EXTENT_REG)
10624                         goto next;
10625                 start = btrfs_file_extent_disk_bytenr(node, fi);
10626                 len = btrfs_file_extent_disk_num_bytes(node, fi);
10627
10628                 ret = populate_csum(trans, csum_root, buf, start, len);
10629                 if (ret == -EEXIST)
10630                         ret = 0;
10631                 if (ret < 0)
10632                         goto out;
10633 next:
10634                 /*
10635                  * TODO: if next leaf is corrupted, jump to nearest next valid
10636                  * leaf.
10637                  */
10638                 ret = btrfs_next_item(cur_root, &path);
10639                 if (ret < 0)
10640                         goto out;
10641                 if (ret > 0) {
10642                         ret = 0;
10643                         goto out;
10644                 }
10645         }
10646
10647 out:
10648         btrfs_release_path(&path);
10649         free(buf);
10650         return ret;
10651 }
10652
10653 static int fill_csum_tree_from_fs(struct btrfs_trans_handle *trans,
10654                                   struct btrfs_root *csum_root)
10655 {
10656         struct btrfs_fs_info *fs_info = csum_root->fs_info;
10657         struct btrfs_path path;
10658         struct btrfs_root *tree_root = fs_info->tree_root;
10659         struct btrfs_root *cur_root;
10660         struct extent_buffer *node;
10661         struct btrfs_key key;
10662         int slot = 0;
10663         int ret = 0;
10664
10665         btrfs_init_path(&path);
10666         key.objectid = BTRFS_FS_TREE_OBJECTID;
10667         key.offset = 0;
10668         key.type = BTRFS_ROOT_ITEM_KEY;
10669         ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
10670         if (ret < 0)
10671                 goto out;
10672         if (ret > 0) {
10673                 ret = -ENOENT;
10674                 goto out;
10675         }
10676
10677         while (1) {
10678                 node = path.nodes[0];
10679                 slot = path.slots[0];
10680                 btrfs_item_key_to_cpu(node, &key, slot);
10681                 if (key.objectid > BTRFS_LAST_FREE_OBJECTID)
10682                         goto out;
10683                 if (key.type != BTRFS_ROOT_ITEM_KEY)
10684                         goto next;
10685                 if (!is_fstree(key.objectid))
10686                         goto next;
10687                 key.offset = (u64)-1;
10688
10689                 cur_root = btrfs_read_fs_root(fs_info, &key);
10690                 if (IS_ERR(cur_root) || !cur_root) {
10691                         fprintf(stderr, "Fail to read fs/subvol tree: %lld\n",
10692                                 key.objectid);
10693                         goto out;
10694                 }
10695                 ret = fill_csum_tree_from_one_fs_root(trans, csum_root,
10696                                 cur_root);
10697                 if (ret < 0)
10698                         goto out;
10699 next:
10700                 ret = btrfs_next_item(tree_root, &path);
10701                 if (ret > 0) {
10702                         ret = 0;
10703                         goto out;
10704                 }
10705                 if (ret < 0)
10706                         goto out;
10707         }
10708
10709 out:
10710         btrfs_release_path(&path);
10711         return ret;
10712 }
10713
10714 static int fill_csum_tree_from_extent(struct btrfs_trans_handle *trans,
10715                                       struct btrfs_root *csum_root)
10716 {
10717         struct btrfs_root *extent_root = csum_root->fs_info->extent_root;
10718         struct btrfs_path path;
10719         struct btrfs_extent_item *ei;
10720         struct extent_buffer *leaf;
10721         char *buf;
10722         struct btrfs_key key;
10723         int ret;
10724
10725         btrfs_init_path(&path);
10726         key.objectid = 0;
10727         key.type = BTRFS_EXTENT_ITEM_KEY;
10728         key.offset = 0;
10729         ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
10730         if (ret < 0) {
10731                 btrfs_release_path(&path);
10732                 return ret;
10733         }
10734
10735         buf = malloc(csum_root->sectorsize);
10736         if (!buf) {
10737                 btrfs_release_path(&path);
10738                 return -ENOMEM;
10739         }
10740
10741         while (1) {
10742                 if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
10743                         ret = btrfs_next_leaf(extent_root, &path);
10744                         if (ret < 0)
10745                                 break;
10746                         if (ret) {
10747                                 ret = 0;
10748                                 break;
10749                         }
10750                 }
10751                 leaf = path.nodes[0];
10752
10753                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
10754                 if (key.type != BTRFS_EXTENT_ITEM_KEY) {
10755                         path.slots[0]++;
10756                         continue;
10757                 }
10758
10759                 ei = btrfs_item_ptr(leaf, path.slots[0],
10760                                     struct btrfs_extent_item);
10761                 if (!(btrfs_extent_flags(leaf, ei) &
10762                       BTRFS_EXTENT_FLAG_DATA)) {
10763                         path.slots[0]++;
10764                         continue;
10765                 }
10766
10767                 ret = populate_csum(trans, csum_root, buf, key.objectid,
10768                                     key.offset);
10769                 if (ret)
10770                         break;
10771                 path.slots[0]++;
10772         }
10773
10774         btrfs_release_path(&path);
10775         free(buf);
10776         return ret;
10777 }
10778
10779 /*
10780  * Recalculate the csum and put it into the csum tree.
10781  *
10782  * Extent tree init will wipe out all the extent info, so in that case, we
10783  * can't depend on extent tree, but use fs tree.  If search_fs_tree is set, we
10784  * will use fs/subvol trees to init the csum tree.
10785  */
10786 static int fill_csum_tree(struct btrfs_trans_handle *trans,
10787                           struct btrfs_root *csum_root,
10788                           int search_fs_tree)
10789 {
10790         if (search_fs_tree)
10791                 return fill_csum_tree_from_fs(trans, csum_root);
10792         else
10793                 return fill_csum_tree_from_extent(trans, csum_root);
10794 }
10795
10796 static void free_roots_info_cache(void)
10797 {
10798         if (!roots_info_cache)
10799                 return;
10800
10801         while (!cache_tree_empty(roots_info_cache)) {
10802                 struct cache_extent *entry;
10803                 struct root_item_info *rii;
10804
10805                 entry = first_cache_extent(roots_info_cache);
10806                 if (!entry)
10807                         break;
10808                 remove_cache_extent(roots_info_cache, entry);
10809                 rii = container_of(entry, struct root_item_info, cache_extent);
10810                 free(rii);
10811         }
10812
10813         free(roots_info_cache);
10814         roots_info_cache = NULL;
10815 }
10816
10817 static int build_roots_info_cache(struct btrfs_fs_info *info)
10818 {
10819         int ret = 0;
10820         struct btrfs_key key;
10821         struct extent_buffer *leaf;
10822         struct btrfs_path path;
10823
10824         if (!roots_info_cache) {
10825                 roots_info_cache = malloc(sizeof(*roots_info_cache));
10826                 if (!roots_info_cache)
10827                         return -ENOMEM;
10828                 cache_tree_init(roots_info_cache);
10829         }
10830
10831         btrfs_init_path(&path);
10832         key.objectid = 0;
10833         key.type = BTRFS_EXTENT_ITEM_KEY;
10834         key.offset = 0;
10835         ret = btrfs_search_slot(NULL, info->extent_root, &key, &path, 0, 0);
10836         if (ret < 0)
10837                 goto out;
10838         leaf = path.nodes[0];
10839
10840         while (1) {
10841                 struct btrfs_key found_key;
10842                 struct btrfs_extent_item *ei;
10843                 struct btrfs_extent_inline_ref *iref;
10844                 int slot = path.slots[0];
10845                 int type;
10846                 u64 flags;
10847                 u64 root_id;
10848                 u8 level;
10849                 struct cache_extent *entry;
10850                 struct root_item_info *rii;
10851
10852                 if (slot >= btrfs_header_nritems(leaf)) {
10853                         ret = btrfs_next_leaf(info->extent_root, &path);
10854                         if (ret < 0) {
10855                                 break;
10856                         } else if (ret) {
10857                                 ret = 0;
10858                                 break;
10859                         }
10860                         leaf = path.nodes[0];
10861                         slot = path.slots[0];
10862                 }
10863
10864                 btrfs_item_key_to_cpu(leaf, &found_key, path.slots[0]);
10865
10866                 if (found_key.type != BTRFS_EXTENT_ITEM_KEY &&
10867                     found_key.type != BTRFS_METADATA_ITEM_KEY)
10868                         goto next;
10869
10870                 ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
10871                 flags = btrfs_extent_flags(leaf, ei);
10872
10873                 if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
10874                     !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
10875                         goto next;
10876
10877                 if (found_key.type == BTRFS_METADATA_ITEM_KEY) {
10878                         iref = (struct btrfs_extent_inline_ref *)(ei + 1);
10879                         level = found_key.offset;
10880                 } else {
10881                         struct btrfs_tree_block_info *binfo;
10882
10883                         binfo = (struct btrfs_tree_block_info *)(ei + 1);
10884                         iref = (struct btrfs_extent_inline_ref *)(binfo + 1);
10885                         level = btrfs_tree_block_level(leaf, binfo);
10886                 }
10887
10888                 /*
10889                  * For a root extent, it must be of the following type and the
10890                  * first (and only one) iref in the item.
10891                  */
10892                 type = btrfs_extent_inline_ref_type(leaf, iref);
10893                 if (type != BTRFS_TREE_BLOCK_REF_KEY)
10894                         goto next;
10895
10896                 root_id = btrfs_extent_inline_ref_offset(leaf, iref);
10897                 entry = lookup_cache_extent(roots_info_cache, root_id, 1);
10898                 if (!entry) {
10899                         rii = malloc(sizeof(struct root_item_info));
10900                         if (!rii) {
10901                                 ret = -ENOMEM;
10902                                 goto out;
10903                         }
10904                         rii->cache_extent.start = root_id;
10905                         rii->cache_extent.size = 1;
10906                         rii->level = (u8)-1;
10907                         entry = &rii->cache_extent;
10908                         ret = insert_cache_extent(roots_info_cache, entry);
10909                         ASSERT(ret == 0);
10910                 } else {
10911                         rii = container_of(entry, struct root_item_info,
10912                                            cache_extent);
10913                 }
10914
10915                 ASSERT(rii->cache_extent.start == root_id);
10916                 ASSERT(rii->cache_extent.size == 1);
10917
10918                 if (level > rii->level || rii->level == (u8)-1) {
10919                         rii->level = level;
10920                         rii->bytenr = found_key.objectid;
10921                         rii->gen = btrfs_extent_generation(leaf, ei);
10922                         rii->node_count = 1;
10923                 } else if (level == rii->level) {
10924                         rii->node_count++;
10925                 }
10926 next:
10927                 path.slots[0]++;
10928         }
10929
10930 out:
10931         btrfs_release_path(&path);
10932
10933         return ret;
10934 }
10935
10936 static int maybe_repair_root_item(struct btrfs_fs_info *info,
10937                                   struct btrfs_path *path,
10938                                   const struct btrfs_key *root_key,
10939                                   const int read_only_mode)
10940 {
10941         const u64 root_id = root_key->objectid;
10942         struct cache_extent *entry;
10943         struct root_item_info *rii;
10944         struct btrfs_root_item ri;
10945         unsigned long offset;
10946
10947         entry = lookup_cache_extent(roots_info_cache, root_id, 1);
10948         if (!entry) {
10949                 fprintf(stderr,
10950                         "Error: could not find extent items for root %llu\n",
10951                         root_key->objectid);
10952                 return -ENOENT;
10953         }
10954
10955         rii = container_of(entry, struct root_item_info, cache_extent);
10956         ASSERT(rii->cache_extent.start == root_id);
10957         ASSERT(rii->cache_extent.size == 1);
10958
10959         if (rii->node_count != 1) {
10960                 fprintf(stderr,
10961                         "Error: could not find btree root extent for root %llu\n",
10962                         root_id);
10963                 return -ENOENT;
10964         }
10965
10966         offset = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
10967         read_extent_buffer(path->nodes[0], &ri, offset, sizeof(ri));
10968
10969         if (btrfs_root_bytenr(&ri) != rii->bytenr ||
10970             btrfs_root_level(&ri) != rii->level ||
10971             btrfs_root_generation(&ri) != rii->gen) {
10972
10973                 /*
10974                  * If we're in repair mode but our caller told us to not update
10975                  * the root item, i.e. just check if it needs to be updated, don't
10976                  * print this message, since the caller will call us again shortly
10977                  * for the same root item without read only mode (the caller will
10978                  * open a transaction first).
10979                  */
10980                 if (!(read_only_mode && repair))
10981                         fprintf(stderr,
10982                                 "%sroot item for root %llu,"
10983                                 " current bytenr %llu, current gen %llu, current level %u,"
10984                                 " new bytenr %llu, new gen %llu, new level %u\n",
10985                                 (read_only_mode ? "" : "fixing "),
10986                                 root_id,
10987                                 btrfs_root_bytenr(&ri), btrfs_root_generation(&ri),
10988                                 btrfs_root_level(&ri),
10989                                 rii->bytenr, rii->gen, rii->level);
10990
10991                 if (btrfs_root_generation(&ri) > rii->gen) {
10992                         fprintf(stderr,
10993                                 "root %llu has a root item with a more recent gen (%llu) compared to the found root node (%llu)\n",
10994                                 root_id, btrfs_root_generation(&ri), rii->gen);
10995                         return -EINVAL;
10996                 }
10997
10998                 if (!read_only_mode) {
10999                         btrfs_set_root_bytenr(&ri, rii->bytenr);
11000                         btrfs_set_root_level(&ri, rii->level);
11001                         btrfs_set_root_generation(&ri, rii->gen);
11002                         write_extent_buffer(path->nodes[0], &ri,
11003                                             offset, sizeof(ri));
11004                 }
11005
11006                 return 1;
11007         }
11008
11009         return 0;
11010 }
11011
11012 /*
11013  * A regression introduced in the 3.17 kernel (more specifically in 3.17-rc2),
11014  * caused read-only snapshots to be corrupted if they were created at a moment
11015  * when the source subvolume/snapshot had orphan items. The issue was that the
11016  * on-disk root items became incorrect, referring to the pre orphan cleanup root
11017  * node instead of the post orphan cleanup root node.
11018  * So this function, and its callees, just detects and fixes those cases. Even
11019  * though the regression was for read-only snapshots, this function applies to
11020  * any snapshot/subvolume root.
11021  * This must be run before any other repair code - not doing it so, makes other
11022  * repair code delete or modify backrefs in the extent tree for example, which
11023  * will result in an inconsistent fs after repairing the root items.
11024  */
11025 static int repair_root_items(struct btrfs_fs_info *info)
11026 {
11027         struct btrfs_path path;
11028         struct btrfs_key key;
11029         struct extent_buffer *leaf;
11030         struct btrfs_trans_handle *trans = NULL;
11031         int ret = 0;
11032         int bad_roots = 0;
11033         int need_trans = 0;
11034
11035         btrfs_init_path(&path);
11036
11037         ret = build_roots_info_cache(info);
11038         if (ret)
11039                 goto out;
11040
11041         key.objectid = BTRFS_FIRST_FREE_OBJECTID;
11042         key.type = BTRFS_ROOT_ITEM_KEY;
11043         key.offset = 0;
11044
11045 again:
11046         /*
11047          * Avoid opening and committing transactions if a leaf doesn't have
11048          * any root items that need to be fixed, so that we avoid rotating
11049          * backup roots unnecessarily.
11050          */
11051         if (need_trans) {
11052                 trans = btrfs_start_transaction(info->tree_root, 1);
11053                 if (IS_ERR(trans)) {
11054                         ret = PTR_ERR(trans);
11055                         goto out;
11056                 }
11057         }
11058
11059         ret = btrfs_search_slot(trans, info->tree_root, &key, &path,
11060                                 0, trans ? 1 : 0);
11061         if (ret < 0)
11062                 goto out;
11063         leaf = path.nodes[0];
11064
11065         while (1) {
11066                 struct btrfs_key found_key;
11067
11068                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
11069                         int no_more_keys = find_next_key(&path, &key);
11070
11071                         btrfs_release_path(&path);
11072                         if (trans) {
11073                                 ret = btrfs_commit_transaction(trans,
11074                                                                info->tree_root);
11075                                 trans = NULL;
11076                                 if (ret < 0)
11077                                         goto out;
11078                         }
11079                         need_trans = 0;
11080                         if (no_more_keys)
11081                                 break;
11082                         goto again;
11083                 }
11084
11085                 btrfs_item_key_to_cpu(leaf, &found_key, path.slots[0]);
11086
11087                 if (found_key.type != BTRFS_ROOT_ITEM_KEY)
11088                         goto next;
11089                 if (found_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
11090                         goto next;
11091
11092                 ret = maybe_repair_root_item(info, &path, &found_key,
11093                                              trans ? 0 : 1);
11094                 if (ret < 0)
11095                         goto out;
11096                 if (ret) {
11097                         if (!trans && repair) {
11098                                 need_trans = 1;
11099                                 key = found_key;
11100                                 btrfs_release_path(&path);
11101                                 goto again;
11102                         }
11103                         bad_roots++;
11104                 }
11105 next:
11106                 path.slots[0]++;
11107         }
11108         ret = 0;
11109 out:
11110         free_roots_info_cache();
11111         btrfs_release_path(&path);
11112         if (trans)
11113                 btrfs_commit_transaction(trans, info->tree_root);
11114         if (ret < 0)
11115                 return ret;
11116
11117         return bad_roots;
11118 }
11119
11120 static int clear_free_space_cache(struct btrfs_fs_info *fs_info)
11121 {
11122         struct btrfs_trans_handle *trans;
11123         struct btrfs_block_group_cache *bg_cache;
11124         u64 current = 0;
11125         int ret = 0;
11126
11127         /* Clear all free space cache inodes and its extent data */
11128         while (1) {
11129                 bg_cache = btrfs_lookup_first_block_group(fs_info, current);
11130                 if (!bg_cache)
11131                         break;
11132                 ret = btrfs_clear_free_space_cache(fs_info, bg_cache);
11133                 if (ret < 0)
11134                         return ret;
11135                 current = bg_cache->key.objectid + bg_cache->key.offset;
11136         }
11137
11138         /* Don't forget to set cache_generation to -1 */
11139         trans = btrfs_start_transaction(fs_info->tree_root, 0);
11140         if (IS_ERR(trans)) {
11141                 error("failed to update super block cache generation");
11142                 return PTR_ERR(trans);
11143         }
11144         btrfs_set_super_cache_generation(fs_info->super_copy, (u64)-1);
11145         btrfs_commit_transaction(trans, fs_info->tree_root);
11146
11147         return ret;
11148 }
11149
11150 const char * const cmd_check_usage[] = {
11151         "btrfs check [options] <device>",
11152         "Check structural integrity of a filesystem (unmounted).",
11153         "Check structural integrity of an unmounted filesystem. Verify internal",
11154         "trees' consistency and item connectivity. In the repair mode try to",
11155         "fix the problems found. ",
11156         "WARNING: the repair mode is considered dangerous",
11157         "",
11158         "-s|--super <superblock>     use this superblock copy",
11159         "-b|--backup                 use the first valid backup root copy",
11160         "--repair                    try to repair the filesystem",
11161         "--readonly                  run in read-only mode (default)",
11162         "--init-csum-tree            create a new CRC tree",
11163         "--init-extent-tree          create a new extent tree",
11164         "--mode <MODE>               allows choice of memory/IO trade-offs",
11165         "                            where MODE is one of:",
11166         "                            original - read inodes and extents to memory (requires",
11167         "                                       more memory, does less IO)",
11168         "                            lowmem   - try to use less memory but read blocks again",
11169         "                                       when needed",
11170         "--check-data-csum           verify checksums of data blocks",
11171         "-Q|--qgroup-report          print a report on qgroup consistency",
11172         "-E|--subvol-extents <subvolid>",
11173         "                            print subvolume extents and sharing state",
11174         "-r|--tree-root <bytenr>     use the given bytenr for the tree root",
11175         "--chunk-root <bytenr>       use the given bytenr for the chunk tree root",
11176         "-p|--progress               indicate progress",
11177         "--clear-space-cache v1|v2   clear space cache for v1 or v2",
11178         "                            NOTE: v1 support implemented",
11179         NULL
11180 };
11181
11182 int cmd_check(int argc, char **argv)
11183 {
11184         struct cache_tree root_cache;
11185         struct btrfs_root *root;
11186         struct btrfs_fs_info *info;
11187         u64 bytenr = 0;
11188         u64 subvolid = 0;
11189         u64 tree_root_bytenr = 0;
11190         u64 chunk_root_bytenr = 0;
11191         char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
11192         int ret;
11193         u64 num;
11194         int init_csum_tree = 0;
11195         int readonly = 0;
11196         int clear_space_cache = 0;
11197         int qgroup_report = 0;
11198         int qgroups_repaired = 0;
11199         unsigned ctree_flags = OPEN_CTREE_EXCLUSIVE;
11200
11201         while(1) {
11202                 int c;
11203                 enum { GETOPT_VAL_REPAIR = 257, GETOPT_VAL_INIT_CSUM,
11204                         GETOPT_VAL_INIT_EXTENT, GETOPT_VAL_CHECK_CSUM,
11205                         GETOPT_VAL_READONLY, GETOPT_VAL_CHUNK_TREE,
11206                         GETOPT_VAL_MODE, GETOPT_VAL_CLEAR_SPACE_CACHE };
11207                 static const struct option long_options[] = {
11208                         { "super", required_argument, NULL, 's' },
11209                         { "repair", no_argument, NULL, GETOPT_VAL_REPAIR },
11210                         { "readonly", no_argument, NULL, GETOPT_VAL_READONLY },
11211                         { "init-csum-tree", no_argument, NULL,
11212                                 GETOPT_VAL_INIT_CSUM },
11213                         { "init-extent-tree", no_argument, NULL,
11214                                 GETOPT_VAL_INIT_EXTENT },
11215                         { "check-data-csum", no_argument, NULL,
11216                                 GETOPT_VAL_CHECK_CSUM },
11217                         { "backup", no_argument, NULL, 'b' },
11218                         { "subvol-extents", required_argument, NULL, 'E' },
11219                         { "qgroup-report", no_argument, NULL, 'Q' },
11220                         { "tree-root", required_argument, NULL, 'r' },
11221                         { "chunk-root", required_argument, NULL,
11222                                 GETOPT_VAL_CHUNK_TREE },
11223                         { "progress", no_argument, NULL, 'p' },
11224                         { "mode", required_argument, NULL,
11225                                 GETOPT_VAL_MODE },
11226                         { "clear-space-cache", required_argument, NULL,
11227                                 GETOPT_VAL_CLEAR_SPACE_CACHE},
11228                         { NULL, 0, NULL, 0}
11229                 };
11230
11231                 c = getopt_long(argc, argv, "as:br:p", long_options, NULL);
11232                 if (c < 0)
11233                         break;
11234                 switch(c) {
11235                         case 'a': /* ignored */ break;
11236                         case 'b':
11237                                 ctree_flags |= OPEN_CTREE_BACKUP_ROOT;
11238                                 break;
11239                         case 's':
11240                                 num = arg_strtou64(optarg);
11241                                 if (num >= BTRFS_SUPER_MIRROR_MAX) {
11242                                         error(
11243                                         "super mirror should be less than %d",
11244                                                 BTRFS_SUPER_MIRROR_MAX);
11245                                         exit(1);
11246                                 }
11247                                 bytenr = btrfs_sb_offset(((int)num));
11248                                 printf("using SB copy %llu, bytenr %llu\n", num,
11249                                        (unsigned long long)bytenr);
11250                                 break;
11251                         case 'Q':
11252                                 qgroup_report = 1;
11253                                 break;
11254                         case 'E':
11255                                 subvolid = arg_strtou64(optarg);
11256                                 break;
11257                         case 'r':
11258                                 tree_root_bytenr = arg_strtou64(optarg);
11259                                 break;
11260                         case GETOPT_VAL_CHUNK_TREE:
11261                                 chunk_root_bytenr = arg_strtou64(optarg);
11262                                 break;
11263                         case 'p':
11264                                 ctx.progress_enabled = true;
11265                                 break;
11266                         case '?':
11267                         case 'h':
11268                                 usage(cmd_check_usage);
11269                         case GETOPT_VAL_REPAIR:
11270                                 printf("enabling repair mode\n");
11271                                 repair = 1;
11272                                 ctree_flags |= OPEN_CTREE_WRITES;
11273                                 break;
11274                         case GETOPT_VAL_READONLY:
11275                                 readonly = 1;
11276                                 break;
11277                         case GETOPT_VAL_INIT_CSUM:
11278                                 printf("Creating a new CRC tree\n");
11279                                 init_csum_tree = 1;
11280                                 repair = 1;
11281                                 ctree_flags |= OPEN_CTREE_WRITES;
11282                                 break;
11283                         case GETOPT_VAL_INIT_EXTENT:
11284                                 init_extent_tree = 1;
11285                                 ctree_flags |= (OPEN_CTREE_WRITES |
11286                                                 OPEN_CTREE_NO_BLOCK_GROUPS);
11287                                 repair = 1;
11288                                 break;
11289                         case GETOPT_VAL_CHECK_CSUM:
11290                                 check_data_csum = 1;
11291                                 break;
11292                         case GETOPT_VAL_MODE:
11293                                 check_mode = parse_check_mode(optarg);
11294                                 if (check_mode == CHECK_MODE_UNKNOWN) {
11295                                         error("unknown mode: %s", optarg);
11296                                         exit(1);
11297                                 }
11298                                 break;
11299                         case GETOPT_VAL_CLEAR_SPACE_CACHE:
11300                                 if (strcmp(optarg, "v1") != 0) {
11301                                         error(
11302                         "only v1 support implmented, unrecognized value %s",
11303                         optarg);
11304                                         exit(1);
11305                                 }
11306                                 clear_space_cache = 1;
11307                                 ctree_flags |= OPEN_CTREE_WRITES;
11308                                 break;
11309                 }
11310         }
11311
11312         if (check_argc_exact(argc - optind, 1))
11313                 usage(cmd_check_usage);
11314
11315         if (ctx.progress_enabled) {
11316                 ctx.tp = TASK_NOTHING;
11317                 ctx.info = task_init(print_status_check, print_status_return, &ctx);
11318         }
11319
11320         /* This check is the only reason for --readonly to exist */
11321         if (readonly && repair) {
11322                 error("repair options are not compatible with --readonly");
11323                 exit(1);
11324         }
11325
11326         /*
11327          * Not supported yet
11328          */
11329         if (repair && check_mode == CHECK_MODE_LOWMEM) {
11330                 error("low memory mode doesn't support repair yet");
11331                 exit(1);
11332         }
11333
11334         radix_tree_init();
11335         cache_tree_init(&root_cache);
11336
11337         if((ret = check_mounted(argv[optind])) < 0) {
11338                 error("could not check mount status: %s", strerror(-ret));
11339                 goto err_out;
11340         } else if(ret) {
11341                 error("%s is currently mounted, aborting", argv[optind]);
11342                 ret = -EBUSY;
11343                 goto err_out;
11344         }
11345
11346         /* only allow partial opening under repair mode */
11347         if (repair)
11348                 ctree_flags |= OPEN_CTREE_PARTIAL;
11349
11350         info = open_ctree_fs_info(argv[optind], bytenr, tree_root_bytenr,
11351                                   chunk_root_bytenr, ctree_flags);
11352         if (!info) {
11353                 error("cannot open file system");
11354                 ret = -EIO;
11355                 goto err_out;
11356         }
11357
11358         global_info = info;
11359         root = info->fs_root;
11360         if (clear_space_cache) {
11361                 if (btrfs_fs_compat_ro(info,
11362                                 BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
11363                         error(
11364                         "free space cache v2 detected, clearing not implemented");
11365                         ret = 1;
11366                         goto close_out;
11367                 }
11368                 printf("Clearing free space cache\n");
11369                 ret = clear_free_space_cache(info);
11370                 if (ret) {
11371                         error("failed to clear free space cache");
11372                         ret = 1;
11373                 } else {
11374                         printf("Free space cache cleared\n");
11375                 }
11376                 goto close_out;
11377         }
11378
11379         /*
11380          * repair mode will force us to commit transaction which
11381          * will make us fail to load log tree when mounting.
11382          */
11383         if (repair && btrfs_super_log_root(info->super_copy)) {
11384                 ret = ask_user("repair mode will force to clear out log tree, are you sure?");
11385                 if (!ret) {
11386                         ret = 1;
11387                         goto close_out;
11388                 }
11389                 ret = zero_log_tree(root);
11390                 if (ret) {
11391                         error("failed to zero log tree: %d", ret);
11392                         goto close_out;
11393                 }
11394         }
11395
11396         uuid_unparse(info->super_copy->fsid, uuidbuf);
11397         if (qgroup_report) {
11398                 printf("Print quota groups for %s\nUUID: %s\n", argv[optind],
11399                        uuidbuf);
11400                 ret = qgroup_verify_all(info);
11401                 if (ret == 0)
11402                         report_qgroups(1);
11403                 goto close_out;
11404         }
11405         if (subvolid) {
11406                 printf("Print extent state for subvolume %llu on %s\nUUID: %s\n",
11407                        subvolid, argv[optind], uuidbuf);
11408                 ret = print_extent_state(info, subvolid);
11409                 goto close_out;
11410         }
11411         printf("Checking filesystem on %s\nUUID: %s\n", argv[optind], uuidbuf);
11412
11413         if (!extent_buffer_uptodate(info->tree_root->node) ||
11414             !extent_buffer_uptodate(info->dev_root->node) ||
11415             !extent_buffer_uptodate(info->chunk_root->node)) {
11416                 error("critical roots corrupted, unable to check the filesystem");
11417                 ret = -EIO;
11418                 goto close_out;
11419         }
11420
11421         if (init_extent_tree || init_csum_tree) {
11422                 struct btrfs_trans_handle *trans;
11423
11424                 trans = btrfs_start_transaction(info->extent_root, 0);
11425                 if (IS_ERR(trans)) {
11426                         error("error starting transaction");
11427                         ret = PTR_ERR(trans);
11428                         goto close_out;
11429                 }
11430
11431                 if (init_extent_tree) {
11432                         printf("Creating a new extent tree\n");
11433                         ret = reinit_extent_tree(trans, info);
11434                         if (ret)
11435                                 goto close_out;
11436                 }
11437
11438                 if (init_csum_tree) {
11439                         printf("Reinitialize checksum tree\n");
11440                         ret = btrfs_fsck_reinit_root(trans, info->csum_root, 0);
11441                         if (ret) {
11442                                 error("checksum tree initialization failed: %d",
11443                                                 ret);
11444                                 ret = -EIO;
11445                                 goto close_out;
11446                         }
11447
11448                         ret = fill_csum_tree(trans, info->csum_root,
11449                                              init_extent_tree);
11450                         if (ret) {
11451                                 error("checksum tree refilling failed: %d", ret);
11452                                 return -EIO;
11453                         }
11454                 }
11455                 /*
11456                  * Ok now we commit and run the normal fsck, which will add
11457                  * extent entries for all of the items it finds.
11458                  */
11459                 ret = btrfs_commit_transaction(trans, info->extent_root);
11460                 if (ret)
11461                         goto close_out;
11462         }
11463         if (!extent_buffer_uptodate(info->extent_root->node)) {
11464                 error("critical: extent_root, unable to check the filesystem");
11465                 ret = -EIO;
11466                 goto close_out;
11467         }
11468         if (!extent_buffer_uptodate(info->csum_root->node)) {
11469                 error("critical: csum_root, unable to check the filesystem");
11470                 ret = -EIO;
11471                 goto close_out;
11472         }
11473
11474         if (!ctx.progress_enabled)
11475                 printf("checking extents");
11476         if (check_mode == CHECK_MODE_LOWMEM)
11477                 ret = check_chunks_and_extents_v2(root);
11478         else
11479                 ret = check_chunks_and_extents(root);
11480         if (ret)
11481                 printf("Errors found in extent allocation tree or chunk allocation");
11482
11483         ret = repair_root_items(info);
11484         if (ret < 0)
11485                 goto close_out;
11486         if (repair) {
11487                 fprintf(stderr, "Fixed %d roots.\n", ret);
11488                 ret = 0;
11489         } else if (ret > 0) {
11490                 fprintf(stderr,
11491                        "Found %d roots with an outdated root item.\n",
11492                        ret);
11493                 fprintf(stderr,
11494                         "Please run a filesystem check with the option --repair to fix them.\n");
11495                 ret = 1;
11496                 goto close_out;
11497         }
11498
11499         if (!ctx.progress_enabled) {
11500                 if (btrfs_fs_compat_ro(info, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE))
11501                         fprintf(stderr, "checking free space tree\n");
11502                 else
11503                         fprintf(stderr, "checking free space cache\n");
11504         }
11505         ret = check_space_cache(root);
11506         if (ret)
11507                 goto out;
11508
11509         /*
11510          * We used to have to have these hole extents in between our real
11511          * extents so if we don't have this flag set we need to make sure there
11512          * are no gaps in the file extents for inodes, otherwise we can just
11513          * ignore it when this happens.
11514          */
11515         no_holes = btrfs_fs_incompat(root->fs_info,
11516                                      BTRFS_FEATURE_INCOMPAT_NO_HOLES);
11517         if (!ctx.progress_enabled)
11518                 fprintf(stderr, "checking fs roots\n");
11519         ret = check_fs_roots(root, &root_cache);
11520         if (ret)
11521                 goto out;
11522
11523         fprintf(stderr, "checking csums\n");
11524         ret = check_csums(root);
11525         if (ret)
11526                 goto out;
11527
11528         fprintf(stderr, "checking root refs\n");
11529         ret = check_root_refs(root, &root_cache);
11530         if (ret)
11531                 goto out;
11532
11533         while (repair && !list_empty(&root->fs_info->recow_ebs)) {
11534                 struct extent_buffer *eb;
11535
11536                 eb = list_first_entry(&root->fs_info->recow_ebs,
11537                                       struct extent_buffer, recow);
11538                 list_del_init(&eb->recow);
11539                 ret = recow_extent_buffer(root, eb);
11540                 if (ret)
11541                         break;
11542         }
11543
11544         while (!list_empty(&delete_items)) {
11545                 struct bad_item *bad;
11546
11547                 bad = list_first_entry(&delete_items, struct bad_item, list);
11548                 list_del_init(&bad->list);
11549                 if (repair)
11550                         ret = delete_bad_item(root, bad);
11551                 free(bad);
11552         }
11553
11554         if (info->quota_enabled) {
11555                 int err;
11556                 fprintf(stderr, "checking quota groups\n");
11557                 err = qgroup_verify_all(info);
11558                 if (err)
11559                         goto out;
11560                 report_qgroups(0);
11561                 err = repair_qgroups(info, &qgroups_repaired);
11562                 if (err)
11563                         goto out;
11564         }
11565
11566         if (!list_empty(&root->fs_info->recow_ebs)) {
11567                 error("transid errors in file system");
11568                 ret = 1;
11569         }
11570 out:
11571         /* Don't override original ret */
11572         if (!ret && qgroups_repaired)
11573                 ret = qgroups_repaired;
11574
11575         if (found_old_backref) { /*
11576                  * there was a disk format change when mixed
11577                  * backref was in testing tree. The old format
11578                  * existed about one week.
11579                  */
11580                 printf("\n * Found old mixed backref format. "
11581                        "The old format is not supported! *"
11582                        "\n * Please mount the FS in readonly mode, "
11583                        "backup data and re-format the FS. *\n\n");
11584                 ret = 1;
11585         }
11586         printf("found %llu bytes used err is %d\n",
11587                (unsigned long long)bytes_used, ret);
11588         printf("total csum bytes: %llu\n",(unsigned long long)total_csum_bytes);
11589         printf("total tree bytes: %llu\n",
11590                (unsigned long long)total_btree_bytes);
11591         printf("total fs tree bytes: %llu\n",
11592                (unsigned long long)total_fs_tree_bytes);
11593         printf("total extent tree bytes: %llu\n",
11594                (unsigned long long)total_extent_tree_bytes);
11595         printf("btree space waste bytes: %llu\n",
11596                (unsigned long long)btree_space_waste);
11597         printf("file data blocks allocated: %llu\n referenced %llu\n",
11598                 (unsigned long long)data_bytes_allocated,
11599                 (unsigned long long)data_bytes_referenced);
11600
11601         free_qgroup_counts();
11602         free_root_recs_tree(&root_cache);
11603 close_out:
11604         close_ctree(root);
11605 err_out:
11606         if (ctx.progress_enabled)
11607                 task_deinit(ctx.info);
11608
11609         return ret;
11610 }