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 "transaction.h"
  34 #include "utils.h"
  35 #include "commands.h"
  36 #include "free-space-cache.h"
  37 #include "btrfsck.h"
  38 #include "qgroup-verify.h"
  39 #include "rbtree-utils.h"
  40 #include "backref.h"
  41 #include "ulist.h"
  42
  43 static u64 bytes_used = 0;
  44 static u64 total_csum_bytes = 0;
  45 static u64 total_btree_bytes = 0;
  46 static u64 total_fs_tree_bytes = 0;
  47 static u64 total_extent_tree_bytes = 0;
  48 static u64 btree_space_waste = 0;
  49 static u64 data_bytes_allocated = 0;
  50 static u64 data_bytes_referenced = 0;
  51 static int found_old_backref = 0;
  52 static LIST_HEAD(duplicate_extents);
  53 static LIST_HEAD(delete_items);
  54 static int repair = 0;
  55 static int no_holes = 0;
  56 static int init_extent_tree = 0;
  57 static int check_data_csum = 0;
  58
  59 struct extent_backref {
  60         struct list_head list;
  61         unsigned int is_data:1;
  62         unsigned int found_extent_tree:1;
  63         unsigned int full_backref:1;
  64         unsigned int found_ref:1;
  65         unsigned int broken:1;
  66 };
  67
  68 struct data_backref {
  69         struct extent_backref node;
  70         union {
  71                 u64 parent;
  72                 u64 root;
  73         };
  74         u64 owner;
  75         u64 offset;
  76         u64 disk_bytenr;
  77         u64 bytes;
  78         u64 ram_bytes;
  79         u32 num_refs;
  80         u32 found_ref;
  81 };
  82
  83 /*
  84  * Much like data_backref, just removed the undetermined members
  85  * and change it to use list_head.
  86  * During extent scan, it is stored in root->orphan_data_extent.
  87  * During fs tree scan, it is then moved to inode_rec->orphan_data_extents.
  88  */
  89 struct orphan_data_extent {
  90         struct list_head list;
  91         u64 root;
  92         u64 objectid;
  93         u64 offset;
  94         u64 disk_bytenr;
  95         u64 disk_len;
  96 };
  97
  98 struct tree_backref {
  99         struct extent_backref node;
 100         union {
 101                 u64 parent;
 102                 u64 root;
 103         };
 104 };
 105
 106 struct extent_record {
 107         struct list_head backrefs;
 108         struct list_head dups;
 109         struct list_head list;
 110         struct cache_extent cache;
 111         struct btrfs_disk_key parent_key;
 112         u64 start;
 113         u64 max_size;
 114         u64 nr;
 115         u64 refs;
 116         u64 extent_item_refs;
 117         u64 generation;
 118         u64 parent_generation;
 119         u64 info_objectid;
 120         u32 num_duplicates;
 121         u8 info_level;
 122         int flag_block_full_backref;
 123         unsigned int found_rec:1;
 124         unsigned int content_checked:1;
 125         unsigned int owner_ref_checked:1;
 126         unsigned int is_root:1;
 127         unsigned int metadata:1;
 128         unsigned int bad_full_backref:1;
 129 };
 130
 131 struct inode_backref {
 132         struct list_head list;
 133         unsigned int found_dir_item:1;
 134         unsigned int found_dir_index:1;
 135         unsigned int found_inode_ref:1;
 136         unsigned int filetype:8;
 137         int errors;
 138         unsigned int ref_type;
 139         u64 dir;
 140         u64 index;
 141         u16 namelen;
 142         char name[0];
 143 };
 144
 145 struct root_item_record {
 146         struct list_head list;
 147         u64 objectid;
 148         u64 bytenr;
 149         u64 last_snapshot;
 150         u8 level;
 151         u8 drop_level;
 152         int level_size;
 153         struct btrfs_key drop_key;
 154 };
 155
 156 #define REF_ERR_NO_DIR_ITEM             (1 << 0)
 157 #define REF_ERR_NO_DIR_INDEX            (1 << 1)
 158 #define REF_ERR_NO_INODE_REF            (1 << 2)
 159 #define REF_ERR_DUP_DIR_ITEM            (1 << 3)
 160 #define REF_ERR_DUP_DIR_INDEX           (1 << 4)
 161 #define REF_ERR_DUP_INODE_REF           (1 << 5)
 162 #define REF_ERR_INDEX_UNMATCH           (1 << 6)
 163 #define REF_ERR_FILETYPE_UNMATCH        (1 << 7)
 164 #define REF_ERR_NAME_TOO_LONG           (1 << 8) // 100
 165 #define REF_ERR_NO_ROOT_REF             (1 << 9)
 166 #define REF_ERR_NO_ROOT_BACKREF         (1 << 10)
 167 #define REF_ERR_DUP_ROOT_REF            (1 << 11)
 168 #define REF_ERR_DUP_ROOT_BACKREF        (1 << 12)
 169
 170 struct file_extent_hole {
 171         struct rb_node node;
 172         u64 start;
 173         u64 len;
 174 };
 175
 176 /* Compatible function to allow reuse of old codes */
 177 static u64 first_extent_gap(struct rb_root *holes)
 178 {
 179         struct file_extent_hole *hole;
 180
 181         if (RB_EMPTY_ROOT(holes))
 182                 return (u64)-1;
 183
 184         hole = rb_entry(rb_first(holes), struct file_extent_hole, node);
 185         return hole->start;
 186 }
 187
 188 int compare_hole(struct rb_node *node1, struct rb_node *node2)
 189 {
 190         struct file_extent_hole *hole1;
 191         struct file_extent_hole *hole2;
 192
 193         hole1 = rb_entry(node1, struct file_extent_hole, node);
 194         hole2 = rb_entry(node2, struct file_extent_hole, node);
 195
 196         if (hole1->start > hole2->start)
 197                 return -1;
 198         if (hole1->start < hole2->start)
 199                 return 1;
 200         /* Now hole1->start == hole2->start */
 201         if (hole1->len >= hole2->len)
 202                 /*
 203                  * Hole 1 will be merge center
 204                  * Same hole will be merged later
 205                  */
 206                 return -1;
 207         /* Hole 2 will be merge center */
 208         return 1;
 209 }
 210
 211 /*
 212  * Add a hole to the record
 213  *
 214  * This will do hole merge for copy_file_extent_holes(),
 215  * which will ensure there won't be continuous holes.
 216  */
 217 static int add_file_extent_hole(struct rb_root *holes,
 218                                 u64 start, u64 len)
 219 {
 220         struct file_extent_hole *hole;
 221         struct file_extent_hole *prev = NULL;
 222         struct file_extent_hole *next = NULL;
 223
 224         hole = malloc(sizeof(*hole));
 225         if (!hole)
 226                 return -ENOMEM;
 227         hole->start = start;
 228         hole->len = len;
 229         /* Since compare will not return 0, no -EEXIST will happen */
 230         rb_insert(holes, &hole->node, compare_hole);
 231
 232         /* simple merge with previous hole */
 233         if (rb_prev(&hole->node))
 234                 prev = rb_entry(rb_prev(&hole->node), struct file_extent_hole,
 235                                 node);
 236         if (prev && prev->start + prev->len >= hole->start) {
 237                 hole->len = hole->start + hole->len - prev->start;
 238                 hole->start = prev->start;
 239                 rb_erase(&prev->node, holes);
 240                 free(prev);
 241                 prev = NULL;
 242         }
 243
 244         /* iterate merge with next holes */
 245         while (1) {
 246                 if (!rb_next(&hole->node))
 247                         break;
 248                 next = rb_entry(rb_next(&hole->node), struct file_extent_hole,
 249                                         node);
 250                 if (hole->start + hole->len >= next->start) {
 251                         if (hole->start + hole->len <= next->start + next->len)
 252                                 hole->len = next->start + next->len -
 253                                             hole->start;
 254                         rb_erase(&next->node, holes);
 255                         free(next);
 256                         next = NULL;
 257                 } else
 258                         break;
 259         }
 260         return 0;
 261 }
 262
 263 static int compare_hole_range(struct rb_node *node, void *data)
 264 {
 265         struct file_extent_hole *hole;
 266         u64 start;
 267
 268         hole = (struct file_extent_hole *)data;
 269         start = hole->start;
 270
 271         hole = rb_entry(node, struct file_extent_hole, node);
 272         if (start < hole->start)
 273                 return -1;
 274         if (start >= hole->start && start < hole->start + hole->len)
 275                 return 0;
 276         return 1;
 277 }
 278
 279 /*
 280  * Delete a hole in the record
 281  *
 282  * This will do the hole split and is much restrict than add.
 283  */
 284 static int del_file_extent_hole(struct rb_root *holes,
 285                                 u64 start, u64 len)
 286 {
 287         struct file_extent_hole *hole;
 288         struct file_extent_hole tmp;
 289         u64 prev_start = 0;
 290         u64 prev_len = 0;
 291         u64 next_start = 0;
 292         u64 next_len = 0;
 293         struct rb_node *node;
 294         int have_prev = 0;
 295         int have_next = 0;
 296         int ret = 0;
 297
 298         tmp.start = start;
 299         tmp.len = len;
 300         node = rb_search(holes, &tmp, compare_hole_range, NULL);
 301         if (!node)
 302                 return -EEXIST;
 303         hole = rb_entry(node, struct file_extent_hole, node);
 304         if (start + len > hole->start + hole->len)
 305                 return -EEXIST;
 306
 307         /*
 308          * Now there will be no overflap, delete the hole and re-add the
 309          * split(s) if they exists.
 310          */
 311         if (start > hole->start) {
 312                 prev_start = hole->start;
 313                 prev_len = start - hole->start;
 314                 have_prev = 1;
 315         }
 316         if (hole->start + hole->len > start + len) {
 317                 next_start = start + len;
 318                 next_len = hole->start + hole->len - start - len;
 319                 have_next = 1;
 320         }
 321         rb_erase(node, holes);
 322         free(hole);
 323         if (have_prev) {
 324                 ret = add_file_extent_hole(holes, prev_start, prev_len);
 325                 if (ret < 0)
 326                         return ret;
 327         }
 328         if (have_next) {
 329                 ret = add_file_extent_hole(holes, next_start, next_len);
 330                 if (ret < 0)
 331                         return ret;
 332         }
 333         return 0;
 334 }
 335
 336 static int copy_file_extent_holes(struct rb_root *dst,
 337                                   struct rb_root *src)
 338 {
 339         struct file_extent_hole *hole;
 340         struct rb_node *node;
 341         int ret = 0;
 342
 343         node = rb_first(src);
 344         while (node) {
 345                 hole = rb_entry(node, struct file_extent_hole, node);
 346                 ret = add_file_extent_hole(dst, hole->start, hole->len);
 347                 if (ret)
 348                         break;
 349                 node = rb_next(node);
 350         }
 351         return ret;
 352 }
 353
 354 static void free_file_extent_holes(struct rb_root *holes)
 355 {
 356         struct rb_node *node;
 357         struct file_extent_hole *hole;
 358
 359         node = rb_first(holes);
 360         while (node) {
 361                 hole = rb_entry(node, struct file_extent_hole, node);
 362                 rb_erase(node, holes);
 363                 free(hole);
 364                 node = rb_first(holes);
 365         }
 366 }
 367
 368 struct inode_record {
 369         struct list_head backrefs;
 370         unsigned int checked:1;
 371         unsigned int merging:1;
 372         unsigned int found_inode_item:1;
 373         unsigned int found_dir_item:1;
 374         unsigned int found_file_extent:1;
 375         unsigned int found_csum_item:1;
 376         unsigned int some_csum_missing:1;
 377         unsigned int nodatasum:1;
 378         int errors;
 379
 380         u64 ino;
 381         u32 nlink;
 382         u32 imode;
 383         u64 isize;
 384         u64 nbytes;
 385
 386         u32 found_link;
 387         u64 found_size;
 388         u64 extent_start;
 389         u64 extent_end;
 390         struct rb_root holes;
 391         struct list_head orphan_extents;
 392
 393         u32 refs;
 394 };
 395
 396 #define I_ERR_NO_INODE_ITEM             (1 << 0)
 397 #define I_ERR_NO_ORPHAN_ITEM            (1 << 1)
 398 #define I_ERR_DUP_INODE_ITEM            (1 << 2)
 399 #define I_ERR_DUP_DIR_INDEX             (1 << 3)
 400 #define I_ERR_ODD_DIR_ITEM              (1 << 4)
 401 #define I_ERR_ODD_FILE_EXTENT           (1 << 5)
 402 #define I_ERR_BAD_FILE_EXTENT           (1 << 6)
 403 #define I_ERR_FILE_EXTENT_OVERLAP       (1 << 7)
 404 #define I_ERR_FILE_EXTENT_DISCOUNT      (1 << 8) // 100
 405 #define I_ERR_DIR_ISIZE_WRONG           (1 << 9)
 406 #define I_ERR_FILE_NBYTES_WRONG         (1 << 10) // 400
 407 #define I_ERR_ODD_CSUM_ITEM             (1 << 11)
 408 #define I_ERR_SOME_CSUM_MISSING         (1 << 12)
 409 #define I_ERR_LINK_COUNT_WRONG          (1 << 13)
 410 #define I_ERR_FILE_EXTENT_ORPHAN        (1 << 14)
 411
 412 struct root_backref {
 413         struct list_head list;
 414         unsigned int found_dir_item:1;
 415         unsigned int found_dir_index:1;
 416         unsigned int found_back_ref:1;
 417         unsigned int found_forward_ref:1;
 418         unsigned int reachable:1;
 419         int errors;
 420         u64 ref_root;
 421         u64 dir;
 422         u64 index;
 423         u16 namelen;
 424         char name[0];
 425 };
 426
 427 struct root_record {
 428         struct list_head backrefs;
 429         struct cache_extent cache;
 430         unsigned int found_root_item:1;
 431         u64 objectid;
 432         u32 found_ref;
 433 };
 434
 435 struct ptr_node {
 436         struct cache_extent cache;
 437         void *data;
 438 };
 439
 440 struct shared_node {
 441         struct cache_extent cache;
 442         struct cache_tree root_cache;
 443         struct cache_tree inode_cache;
 444         struct inode_record *current;
 445         u32 refs;
 446 };
 447
 448 struct block_info {
 449         u64 start;
 450         u32 size;
 451 };
 452
 453 struct walk_control {
 454         struct cache_tree shared;
 455         struct shared_node *nodes[BTRFS_MAX_LEVEL];
 456         int active_node;
 457         int root_level;
 458 };
 459
 460 struct bad_item {
 461         struct btrfs_key key;
 462         u64 root_id;
 463         struct list_head list;
 464 };
 465
 466 static void reset_cached_block_groups(struct btrfs_fs_info *fs_info);
 467
 468 static void record_root_in_trans(struct btrfs_trans_handle *trans,
 469                                  struct btrfs_root *root)
 470 {
 471         if (root->last_trans != trans->transid) {
 472                 root->track_dirty = 1;
 473                 root->last_trans = trans->transid;
 474                 root->commit_root = root->node;
 475                 extent_buffer_get(root->node);
 476         }
 477 }
 478
 479 static u8 imode_to_type(u32 imode)
 480 {
 481 #define S_SHIFT 12
 482         static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
 483                 [S_IFREG >> S_SHIFT]    = BTRFS_FT_REG_FILE,
 484                 [S_IFDIR >> S_SHIFT]    = BTRFS_FT_DIR,
 485                 [S_IFCHR >> S_SHIFT]    = BTRFS_FT_CHRDEV,
 486                 [S_IFBLK >> S_SHIFT]    = BTRFS_FT_BLKDEV,
 487                 [S_IFIFO >> S_SHIFT]    = BTRFS_FT_FIFO,
 488                 [S_IFSOCK >> S_SHIFT]   = BTRFS_FT_SOCK,
 489                 [S_IFLNK >> S_SHIFT]    = BTRFS_FT_SYMLINK,
 490         };
 491
 492         return btrfs_type_by_mode[(imode & S_IFMT) >> S_SHIFT];
 493 #undef S_SHIFT
 494 }
 495
 496 static int device_record_compare(struct rb_node *node1, struct rb_node *node2)
 497 {
 498         struct device_record *rec1;
 499         struct device_record *rec2;
 500
 501         rec1 = rb_entry(node1, struct device_record, node);
 502         rec2 = rb_entry(node2, struct device_record, node);
 503         if (rec1->devid > rec2->devid)
 504                 return -1;
 505         else if (rec1->devid < rec2->devid)
 506                 return 1;
 507         else
 508                 return 0;
 509 }
 510
 511 static struct inode_record *clone_inode_rec(struct inode_record *orig_rec)
 512 {
 513         struct inode_record *rec;
 514         struct inode_backref *backref;
 515         struct inode_backref *orig;
 516         struct orphan_data_extent *src_orphan;
 517         struct orphan_data_extent *dst_orphan;
 518         size_t size;
 519         int ret;
 520
 521         rec = malloc(sizeof(*rec));
 522         memcpy(rec, orig_rec, sizeof(*rec));
 523         rec->refs = 1;
 524         INIT_LIST_HEAD(&rec->backrefs);
 525         INIT_LIST_HEAD(&rec->orphan_extents);
 526         rec->holes = RB_ROOT;
 527
 528         list_for_each_entry(orig, &orig_rec->backrefs, list) {
 529                 size = sizeof(*orig) + orig->namelen + 1;
 530                 backref = malloc(size);
 531                 memcpy(backref, orig, size);
 532                 list_add_tail(&backref->list, &rec->backrefs);
 533         }
 534         list_for_each_entry(src_orphan, &orig_rec->orphan_extents, list) {
 535                 dst_orphan = malloc(sizeof(*dst_orphan));
 536                 /* TODO: Fix all the HELL of un-catched -ENOMEM case */
 537                 BUG_ON(!dst_orphan);
 538                 memcpy(dst_orphan, src_orphan, sizeof(*src_orphan));
 539                 list_add_tail(&dst_orphan->list, &rec->orphan_extents);
 540         }
 541         ret = copy_file_extent_holes(&rec->holes, &orig_rec->holes);
 542         BUG_ON(ret < 0);
 543
 544         return rec;
 545 }
 546
 547 static void print_orphan_data_extents(struct list_head *orphan_extents,
 548                                       u64 objectid)
 549 {
 550         struct orphan_data_extent *orphan;
 551
 552         if (list_empty(orphan_extents))
 553                 return;
 554         printf("The following data extent is lost in tree %llu:\n",
 555                objectid);
 556         list_for_each_entry(orphan, orphan_extents, list) {
 557                 printf("\tinode: %llu, offset:%llu, disk_bytenr: %llu, disk_len: %llu\n",
 558                        orphan->objectid, orphan->offset, orphan->disk_bytenr,
 559                        orphan->disk_len);
 560         }
 561 }
 562
 563 static void print_inode_error(struct btrfs_root *root, struct inode_record *rec)
 564 {
 565         u64 root_objectid = root->root_key.objectid;
 566         int errors = rec->errors;
 567
 568         if (!errors)
 569                 return;
 570         /* reloc root errors, we print its corresponding fs root objectid*/
 571         if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
 572                 root_objectid = root->root_key.offset;
 573                 fprintf(stderr, "reloc");
 574         }
 575         fprintf(stderr, "root %llu inode %llu errors %x",
 576                 (unsigned long long) root_objectid,
 577                 (unsigned long long) rec->ino, rec->errors);
 578
 579         if (errors & I_ERR_NO_INODE_ITEM)
 580                 fprintf(stderr, ", no inode item");
 581         if (errors & I_ERR_NO_ORPHAN_ITEM)
 582                 fprintf(stderr, ", no orphan item");
 583         if (errors & I_ERR_DUP_INODE_ITEM)
 584                 fprintf(stderr, ", dup inode item");
 585         if (errors & I_ERR_DUP_DIR_INDEX)
 586                 fprintf(stderr, ", dup dir index");
 587         if (errors & I_ERR_ODD_DIR_ITEM)
 588                 fprintf(stderr, ", odd dir item");
 589         if (errors & I_ERR_ODD_FILE_EXTENT)
 590                 fprintf(stderr, ", odd file extent");
 591         if (errors & I_ERR_BAD_FILE_EXTENT)
 592                 fprintf(stderr, ", bad file extent");
 593         if (errors & I_ERR_FILE_EXTENT_OVERLAP)
 594                 fprintf(stderr, ", file extent overlap");
 595         if (errors & I_ERR_FILE_EXTENT_DISCOUNT)
 596                 fprintf(stderr, ", file extent discount");
 597         if (errors & I_ERR_DIR_ISIZE_WRONG)
 598                 fprintf(stderr, ", dir isize wrong");
 599         if (errors & I_ERR_FILE_NBYTES_WRONG)
 600                 fprintf(stderr, ", nbytes wrong");
 601         if (errors & I_ERR_ODD_CSUM_ITEM)
 602                 fprintf(stderr, ", odd csum item");
 603         if (errors & I_ERR_SOME_CSUM_MISSING)
 604                 fprintf(stderr, ", some csum missing");
 605         if (errors & I_ERR_LINK_COUNT_WRONG)
 606                 fprintf(stderr, ", link count wrong");
 607         if (errors & I_ERR_FILE_EXTENT_ORPHAN)
 608                 fprintf(stderr, ", orphan file extent");
 609         fprintf(stderr, "\n");
 610         /* Print the orphan extents if needed */
 611         if (errors & I_ERR_FILE_EXTENT_ORPHAN)
 612                 print_orphan_data_extents(&rec->orphan_extents, root->objectid);
 613
 614         /* Print the holes if needed */
 615         if (errors & I_ERR_FILE_EXTENT_DISCOUNT) {
 616                 struct file_extent_hole *hole;
 617                 struct rb_node *node;
 618
 619                 node = rb_first(&rec->holes);
 620                 fprintf(stderr, "Found file extent holes:\n");
 621                 while (node) {
 622                         hole = rb_entry(node, struct file_extent_hole, node);
 623                         fprintf(stderr, "\tstart: %llu, len:%llu\n",
 624                                 hole->start, hole->len);
 625                         node = rb_next(node);
 626                 }
 627         }
 628 }
 629
 630 static void print_ref_error(int errors)
 631 {
 632         if (errors & REF_ERR_NO_DIR_ITEM)
 633                 fprintf(stderr, ", no dir item");
 634         if (errors & REF_ERR_NO_DIR_INDEX)
 635                 fprintf(stderr, ", no dir index");
 636         if (errors & REF_ERR_NO_INODE_REF)
 637                 fprintf(stderr, ", no inode ref");
 638         if (errors & REF_ERR_DUP_DIR_ITEM)
 639                 fprintf(stderr, ", dup dir item");
 640         if (errors & REF_ERR_DUP_DIR_INDEX)
 641                 fprintf(stderr, ", dup dir index");
 642         if (errors & REF_ERR_DUP_INODE_REF)
 643                 fprintf(stderr, ", dup inode ref");
 644         if (errors & REF_ERR_INDEX_UNMATCH)
 645                 fprintf(stderr, ", index unmatch");
 646         if (errors & REF_ERR_FILETYPE_UNMATCH)
 647                 fprintf(stderr, ", filetype unmatch");
 648         if (errors & REF_ERR_NAME_TOO_LONG)
 649                 fprintf(stderr, ", name too long");
 650         if (errors & REF_ERR_NO_ROOT_REF)
 651                 fprintf(stderr, ", no root ref");
 652         if (errors & REF_ERR_NO_ROOT_BACKREF)
 653                 fprintf(stderr, ", no root backref");
 654         if (errors & REF_ERR_DUP_ROOT_REF)
 655                 fprintf(stderr, ", dup root ref");
 656         if (errors & REF_ERR_DUP_ROOT_BACKREF)
 657                 fprintf(stderr, ", dup root backref");
 658         fprintf(stderr, "\n");
 659 }
 660
 661 static struct inode_record *get_inode_rec(struct cache_tree *inode_cache,
 662                                           u64 ino, int mod)
 663 {
 664         struct ptr_node *node;
 665         struct cache_extent *cache;
 666         struct inode_record *rec = NULL;
 667         int ret;
 668
 669         cache = lookup_cache_extent(inode_cache, ino, 1);
 670         if (cache) {
 671                 node = container_of(cache, struct ptr_node, cache);
 672                 rec = node->data;
 673                 if (mod && rec->refs > 1) {
 674                         node->data = clone_inode_rec(rec);
 675                         rec->refs--;
 676                         rec = node->data;
 677                 }
 678         } else if (mod) {
 679                 rec = calloc(1, sizeof(*rec));
 680                 rec->ino = ino;
 681                 rec->extent_start = (u64)-1;
 682                 rec->refs = 1;
 683                 INIT_LIST_HEAD(&rec->backrefs);
 684                 INIT_LIST_HEAD(&rec->orphan_extents);
 685                 rec->holes = RB_ROOT;
 686
 687                 node = malloc(sizeof(*node));
 688                 node->cache.start = ino;
 689                 node->cache.size = 1;
 690                 node->data = rec;
 691
 692                 if (ino == BTRFS_FREE_INO_OBJECTID)
 693                         rec->found_link = 1;
 694
 695                 ret = insert_cache_extent(inode_cache, &node->cache);
 696                 BUG_ON(ret);
 697         }
 698         return rec;
 699 }
 700
 701 static void free_orphan_data_extents(struct list_head *orphan_extents)
 702 {
 703         struct orphan_data_extent *orphan;
 704
 705         while (!list_empty(orphan_extents)) {
 706                 orphan = list_entry(orphan_extents->next,
 707                                     struct orphan_data_extent, list);
 708                 list_del(&orphan->list);
 709                 free(orphan);
 710         }
 711 }
 712
 713 static void free_inode_rec(struct inode_record *rec)
 714 {
 715         struct inode_backref *backref;
 716
 717         if (--rec->refs > 0)
 718                 return;
 719
 720         while (!list_empty(&rec->backrefs)) {
 721                 backref = list_entry(rec->backrefs.next,
 722                                      struct inode_backref, list);
 723                 list_del(&backref->list);
 724                 free(backref);
 725         }
 726         free_orphan_data_extents(&rec->orphan_extents);
 727         free_file_extent_holes(&rec->holes);
 728         free(rec);
 729 }
 730
 731 static int can_free_inode_rec(struct inode_record *rec)
 732 {
 733         if (!rec->errors && rec->checked && rec->found_inode_item &&
 734             rec->nlink == rec->found_link && list_empty(&rec->backrefs))
 735                 return 1;
 736         return 0;
 737 }
 738
 739 static void maybe_free_inode_rec(struct cache_tree *inode_cache,
 740                                  struct inode_record *rec)
 741 {
 742         struct cache_extent *cache;
 743         struct inode_backref *tmp, *backref;
 744         struct ptr_node *node;
 745         unsigned char filetype;
 746
 747         if (!rec->found_inode_item)
 748                 return;
 749
 750         filetype = imode_to_type(rec->imode);
 751         list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
 752                 if (backref->found_dir_item && backref->found_dir_index) {
 753                         if (backref->filetype != filetype)
 754                                 backref->errors |= REF_ERR_FILETYPE_UNMATCH;
 755                         if (!backref->errors && backref->found_inode_ref) {
 756                                 list_del(&backref->list);
 757                                 free(backref);
 758                         }
 759                 }
 760         }
 761
 762         if (!rec->checked || rec->merging)
 763                 return;
 764
 765         if (S_ISDIR(rec->imode)) {
 766                 if (rec->found_size != rec->isize)
 767                         rec->errors |= I_ERR_DIR_ISIZE_WRONG;
 768                 if (rec->found_file_extent)
 769                         rec->errors |= I_ERR_ODD_FILE_EXTENT;
 770         } else if (S_ISREG(rec->imode) || S_ISLNK(rec->imode)) {
 771                 if (rec->found_dir_item)
 772                         rec->errors |= I_ERR_ODD_DIR_ITEM;
 773                 if (rec->found_size != rec->nbytes)
 774                         rec->errors |= I_ERR_FILE_NBYTES_WRONG;
 775                 if (rec->nlink > 0 && !no_holes &&
 776                     (rec->extent_end < rec->isize ||
 777                      first_extent_gap(&rec->holes) < rec->isize))
 778                         rec->errors |= I_ERR_FILE_EXTENT_DISCOUNT;
 779         }
 780
 781         if (S_ISREG(rec->imode) || S_ISLNK(rec->imode)) {
 782                 if (rec->found_csum_item && rec->nodatasum)
 783                         rec->errors |= I_ERR_ODD_CSUM_ITEM;
 784                 if (rec->some_csum_missing && !rec->nodatasum)
 785                         rec->errors |= I_ERR_SOME_CSUM_MISSING;
 786         }
 787
 788         BUG_ON(rec->refs != 1);
 789         if (can_free_inode_rec(rec)) {
 790                 cache = lookup_cache_extent(inode_cache, rec->ino, 1);
 791                 node = container_of(cache, struct ptr_node, cache);
 792                 BUG_ON(node->data != rec);
 793                 remove_cache_extent(inode_cache, &node->cache);
 794                 free(node);
 795                 free_inode_rec(rec);
 796         }
 797 }
 798
 799 static int check_orphan_item(struct btrfs_root *root, u64 ino)
 800 {
 801         struct btrfs_path path;
 802         struct btrfs_key key;
 803         int ret;
 804
 805         key.objectid = BTRFS_ORPHAN_OBJECTID;
 806         key.type = BTRFS_ORPHAN_ITEM_KEY;
 807         key.offset = ino;
 808
 809         btrfs_init_path(&path);
 810         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
 811         btrfs_release_path(&path);
 812         if (ret > 0)
 813                 ret = -ENOENT;
 814         return ret;
 815 }
 816
 817 static int process_inode_item(struct extent_buffer *eb,
 818                               int slot, struct btrfs_key *key,
 819                               struct shared_node *active_node)
 820 {
 821         struct inode_record *rec;
 822         struct btrfs_inode_item *item;
 823
 824         rec = active_node->current;
 825         BUG_ON(rec->ino != key->objectid || rec->refs > 1);
 826         if (rec->found_inode_item) {
 827                 rec->errors |= I_ERR_DUP_INODE_ITEM;
 828                 return 1;
 829         }
 830         item = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
 831         rec->nlink = btrfs_inode_nlink(eb, item);
 832         rec->isize = btrfs_inode_size(eb, item);
 833         rec->nbytes = btrfs_inode_nbytes(eb, item);
 834         rec->imode = btrfs_inode_mode(eb, item);
 835         if (btrfs_inode_flags(eb, item) & BTRFS_INODE_NODATASUM)
 836                 rec->nodatasum = 1;
 837         rec->found_inode_item = 1;
 838         if (rec->nlink == 0)
 839                 rec->errors |= I_ERR_NO_ORPHAN_ITEM;
 840         maybe_free_inode_rec(&active_node->inode_cache, rec);
 841         return 0;
 842 }
 843
 844 static struct inode_backref *get_inode_backref(struct inode_record *rec,
 845                                                 const char *name,
 846                                                 int namelen, u64 dir)
 847 {
 848         struct inode_backref *backref;
 849
 850         list_for_each_entry(backref, &rec->backrefs, list) {
 851                 if (rec->ino == BTRFS_MULTIPLE_OBJECTIDS)
 852                         break;
 853                 if (backref->dir != dir || backref->namelen != namelen)
 854                         continue;
 855                 if (memcmp(name, backref->name, namelen))
 856                         continue;
 857                 return backref;
 858         }
 859
 860         backref = malloc(sizeof(*backref) + namelen + 1);
 861         memset(backref, 0, sizeof(*backref));
 862         backref->dir = dir;
 863         backref->namelen = namelen;
 864         memcpy(backref->name, name, namelen);
 865         backref->name[namelen] = '\0';
 866         list_add_tail(&backref->list, &rec->backrefs);
 867         return backref;
 868 }
 869
 870 static int add_inode_backref(struct cache_tree *inode_cache,
 871                              u64 ino, u64 dir, u64 index,
 872                              const char *name, int namelen,
 873                              int filetype, int itemtype, int errors)
 874 {
 875         struct inode_record *rec;
 876         struct inode_backref *backref;
 877
 878         rec = get_inode_rec(inode_cache, ino, 1);
 879         backref = get_inode_backref(rec, name, namelen, dir);
 880         if (errors)
 881                 backref->errors |= errors;
 882         if (itemtype == BTRFS_DIR_INDEX_KEY) {
 883                 if (backref->found_dir_index)
 884                         backref->errors |= REF_ERR_DUP_DIR_INDEX;
 885                 if (backref->found_inode_ref && backref->index != index)
 886                         backref->errors |= REF_ERR_INDEX_UNMATCH;
 887                 if (backref->found_dir_item && backref->filetype != filetype)
 888                         backref->errors |= REF_ERR_FILETYPE_UNMATCH;
 889
 890                 backref->index = index;
 891                 backref->filetype = filetype;
 892                 backref->found_dir_index = 1;
 893         } else if (itemtype == BTRFS_DIR_ITEM_KEY) {
 894                 rec->found_link++;
 895                 if (backref->found_dir_item)
 896                         backref->errors |= REF_ERR_DUP_DIR_ITEM;
 897                 if (backref->found_dir_index && backref->filetype != filetype)
 898                         backref->errors |= REF_ERR_FILETYPE_UNMATCH;
 899
 900                 backref->filetype = filetype;
 901                 backref->found_dir_item = 1;
 902         } else if ((itemtype == BTRFS_INODE_REF_KEY) ||
 903                    (itemtype == BTRFS_INODE_EXTREF_KEY)) {
 904                 if (backref->found_inode_ref)
 905                         backref->errors |= REF_ERR_DUP_INODE_REF;
 906                 if (backref->found_dir_index && backref->index != index)
 907                         backref->errors |= REF_ERR_INDEX_UNMATCH;
 908                 else
 909                         backref->index = index;
 910
 911                 backref->ref_type = itemtype;
 912                 backref->found_inode_ref = 1;
 913         } else {
 914                 BUG_ON(1);
 915         }
 916
 917         maybe_free_inode_rec(inode_cache, rec);
 918         return 0;
 919 }
 920
 921 static int merge_inode_recs(struct inode_record *src, struct inode_record *dst,
 922                             struct cache_tree *dst_cache)
 923 {
 924         struct inode_backref *backref;
 925         u32 dir_count = 0;
 926         int ret = 0;
 927
 928         dst->merging = 1;
 929         list_for_each_entry(backref, &src->backrefs, list) {
 930                 if (backref->found_dir_index) {
 931                         add_inode_backref(dst_cache, dst->ino, backref->dir,
 932                                         backref->index, backref->name,
 933                                         backref->namelen, backref->filetype,
 934                                         BTRFS_DIR_INDEX_KEY, backref->errors);
 935                 }
 936                 if (backref->found_dir_item) {
 937                         dir_count++;
 938                         add_inode_backref(dst_cache, dst->ino,
 939                                         backref->dir, 0, backref->name,
 940                                         backref->namelen, backref->filetype,
 941                                         BTRFS_DIR_ITEM_KEY, backref->errors);
 942                 }
 943                 if (backref->found_inode_ref) {
 944                         add_inode_backref(dst_cache, dst->ino,
 945                                         backref->dir, backref->index,
 946                                         backref->name, backref->namelen, 0,
 947                                         backref->ref_type, backref->errors);
 948                 }
 949         }
 950
 951         if (src->found_dir_item)
 952                 dst->found_dir_item = 1;
 953         if (src->found_file_extent)
 954                 dst->found_file_extent = 1;
 955         if (src->found_csum_item)
 956                 dst->found_csum_item = 1;
 957         if (src->some_csum_missing)
 958                 dst->some_csum_missing = 1;
 959         if (first_extent_gap(&dst->holes) > first_extent_gap(&src->holes)) {
 960                 ret = copy_file_extent_holes(&dst->holes, &src->holes);
 961                 if (ret < 0)
 962                         return ret;
 963         }
 964
 965         BUG_ON(src->found_link < dir_count);
 966         dst->found_link += src->found_link - dir_count;
 967         dst->found_size += src->found_size;
 968         if (src->extent_start != (u64)-1) {
 969                 if (dst->extent_start == (u64)-1) {
 970                         dst->extent_start = src->extent_start;
 971                         dst->extent_end = src->extent_end;
 972                 } else {
 973                         if (dst->extent_end > src->extent_start)
 974                                 dst->errors |= I_ERR_FILE_EXTENT_OVERLAP;
 975                         else if (dst->extent_end < src->extent_start) {
 976                                 ret = add_file_extent_hole(&dst->holes,
 977                                         dst->extent_end,
 978                                         src->extent_start - dst->extent_end);
 979                         }
 980                         if (dst->extent_end < src->extent_end)
 981                                 dst->extent_end = src->extent_end;
 982                 }
 983         }
 984
 985         dst->errors |= src->errors;
 986         if (src->found_inode_item) {
 987                 if (!dst->found_inode_item) {
 988                         dst->nlink = src->nlink;
 989                         dst->isize = src->isize;
 990                         dst->nbytes = src->nbytes;
 991                         dst->imode = src->imode;
 992                         dst->nodatasum = src->nodatasum;
 993                         dst->found_inode_item = 1;
 994                 } else {
 995                         dst->errors |= I_ERR_DUP_INODE_ITEM;
 996                 }
 997         }
 998         dst->merging = 0;
 999
1000         return 0;
1001 }
1002
1003 static int splice_shared_node(struct shared_node *src_node,
1004                               struct shared_node *dst_node)
1005 {
1006         struct cache_extent *cache;
1007         struct ptr_node *node, *ins;
1008         struct cache_tree *src, *dst;
1009         struct inode_record *rec, *conflict;
1010         u64 current_ino = 0;
1011         int splice = 0;
1012         int ret;
1013
1014         if (--src_node->refs == 0)
1015                 splice = 1;
1016         if (src_node->current)
1017                 current_ino = src_node->current->ino;
1018
1019         src = &src_node->root_cache;
1020         dst = &dst_node->root_cache;
1021 again:
1022         cache = search_cache_extent(src, 0);
1023         while (cache) {
1024                 node = container_of(cache, struct ptr_node, cache);
1025                 rec = node->data;
1026                 cache = next_cache_extent(cache);
1027
1028                 if (splice) {
1029                         remove_cache_extent(src, &node->cache);
1030                         ins = node;
1031                 } else {
1032                         ins = malloc(sizeof(*ins));
1033                         ins->cache.start = node->cache.start;
1034                         ins->cache.size = node->cache.size;
1035                         ins->data = rec;
1036                         rec->refs++;
1037                 }
1038                 ret = insert_cache_extent(dst, &ins->cache);
1039                 if (ret == -EEXIST) {
1040                         conflict = get_inode_rec(dst, rec->ino, 1);
1041                         merge_inode_recs(rec, conflict, dst);
1042                         if (rec->checked) {
1043                                 conflict->checked = 1;
1044                                 if (dst_node->current == conflict)
1045                                         dst_node->current = NULL;
1046                         }
1047                         maybe_free_inode_rec(dst, conflict);
1048                         free_inode_rec(rec);
1049                         free(ins);
1050                 } else {
1051                         BUG_ON(ret);
1052                 }
1053         }
1054
1055         if (src == &src_node->root_cache) {
1056                 src = &src_node->inode_cache;
1057                 dst = &dst_node->inode_cache;
1058                 goto again;
1059         }
1060
1061         if (current_ino > 0 && (!dst_node->current ||
1062             current_ino > dst_node->current->ino)) {
1063                 if (dst_node->current) {
1064                         dst_node->current->checked = 1;
1065                         maybe_free_inode_rec(dst, dst_node->current);
1066                 }
1067                 dst_node->current = get_inode_rec(dst, current_ino, 1);
1068         }
1069         return 0;
1070 }
1071
1072 static void free_inode_ptr(struct cache_extent *cache)
1073 {
1074         struct ptr_node *node;
1075         struct inode_record *rec;
1076
1077         node = container_of(cache, struct ptr_node, cache);
1078         rec = node->data;
1079         free_inode_rec(rec);
1080         free(node);
1081 }
1082
1083 FREE_EXTENT_CACHE_BASED_TREE(inode_recs, free_inode_ptr);
1084
1085 static struct shared_node *find_shared_node(struct cache_tree *shared,
1086                                             u64 bytenr)
1087 {
1088         struct cache_extent *cache;
1089         struct shared_node *node;
1090
1091         cache = lookup_cache_extent(shared, bytenr, 1);
1092         if (cache) {
1093                 node = container_of(cache, struct shared_node, cache);
1094                 return node;
1095         }
1096         return NULL;
1097 }
1098
1099 static int add_shared_node(struct cache_tree *shared, u64 bytenr, u32 refs)
1100 {
1101         int ret;
1102         struct shared_node *node;
1103
1104         node = calloc(1, sizeof(*node));
1105         node->cache.start = bytenr;
1106         node->cache.size = 1;
1107         cache_tree_init(&node->root_cache);
1108         cache_tree_init(&node->inode_cache);
1109         node->refs = refs;
1110
1111         ret = insert_cache_extent(shared, &node->cache);
1112         BUG_ON(ret);
1113         return 0;
1114 }
1115
1116 static int enter_shared_node(struct btrfs_root *root, u64 bytenr, u32 refs,
1117                              struct walk_control *wc, int level)
1118 {
1119         struct shared_node *node;
1120         struct shared_node *dest;
1121
1122         if (level == wc->active_node)
1123                 return 0;
1124
1125         BUG_ON(wc->active_node <= level);
1126         node = find_shared_node(&wc->shared, bytenr);
1127         if (!node) {
1128                 add_shared_node(&wc->shared, bytenr, refs);
1129                 node = find_shared_node(&wc->shared, bytenr);
1130                 wc->nodes[level] = node;
1131                 wc->active_node = level;
1132                 return 0;
1133         }
1134
1135         if (wc->root_level == wc->active_node &&
1136             btrfs_root_refs(&root->root_item) == 0) {
1137                 if (--node->refs == 0) {
1138                         free_inode_recs_tree(&node->root_cache);
1139                         free_inode_recs_tree(&node->inode_cache);
1140                         remove_cache_extent(&wc->shared, &node->cache);
1141                         free(node);
1142                 }
1143                 return 1;
1144         }
1145
1146         dest = wc->nodes[wc->active_node];
1147         splice_shared_node(node, dest);
1148         if (node->refs == 0) {
1149                 remove_cache_extent(&wc->shared, &node->cache);
1150                 free(node);
1151         }
1152         return 1;
1153 }
1154
1155 static int leave_shared_node(struct btrfs_root *root,
1156                              struct walk_control *wc, int level)
1157 {
1158         struct shared_node *node;
1159         struct shared_node *dest;
1160         int i;
1161
1162         if (level == wc->root_level)
1163                 return 0;
1164
1165         for (i = level + 1; i < BTRFS_MAX_LEVEL; i++) {
1166                 if (wc->nodes[i])
1167                         break;
1168         }
1169         BUG_ON(i >= BTRFS_MAX_LEVEL);
1170
1171         node = wc->nodes[wc->active_node];
1172         wc->nodes[wc->active_node] = NULL;
1173         wc->active_node = i;
1174
1175         dest = wc->nodes[wc->active_node];
1176         if (wc->active_node < wc->root_level ||
1177             btrfs_root_refs(&root->root_item) > 0) {
1178                 BUG_ON(node->refs <= 1);
1179                 splice_shared_node(node, dest);
1180         } else {
1181                 BUG_ON(node->refs < 2);
1182                 node->refs--;
1183         }
1184         return 0;
1185 }
1186
1187 /*
1188  * Returns:
1189  * < 0 - on error
1190  * 1   - if the root with id child_root_id is a child of root parent_root_id
1191  * 0   - if the root child_root_id isn't a child of the root parent_root_id but
1192  *       has other root(s) as parent(s)
1193  * 2   - if the root child_root_id doesn't have any parent roots
1194  */
1195 static int is_child_root(struct btrfs_root *root, u64 parent_root_id,
1196                          u64 child_root_id)
1197 {
1198         struct btrfs_path path;
1199         struct btrfs_key key;
1200         struct extent_buffer *leaf;
1201         int has_parent = 0;
1202         int ret;
1203
1204         btrfs_init_path(&path);
1205
1206         key.objectid = parent_root_id;
1207         key.type = BTRFS_ROOT_REF_KEY;
1208         key.offset = child_root_id;
1209         ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, &path,
1210                                 0, 0);
1211         if (ret < 0)
1212                 return ret;
1213         btrfs_release_path(&path);
1214         if (!ret)
1215                 return 1;
1216
1217         key.objectid = child_root_id;
1218         key.type = BTRFS_ROOT_BACKREF_KEY;
1219         key.offset = 0;
1220         ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, &path,
1221                                 0, 0);
1222         if (ret < 0)
1223                 goto out;
1224
1225         while (1) {
1226                 leaf = path.nodes[0];
1227                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
1228                         ret = btrfs_next_leaf(root->fs_info->tree_root, &path);
1229                         if (ret)
1230                                 break;
1231                         leaf = path.nodes[0];
1232                 }
1233
1234                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1235                 if (key.objectid != child_root_id ||
1236                     key.type != BTRFS_ROOT_BACKREF_KEY)
1237                         break;
1238
1239                 has_parent = 1;
1240
1241                 if (key.offset == parent_root_id) {
1242                         btrfs_release_path(&path);
1243                         return 1;
1244                 }
1245
1246                 path.slots[0]++;
1247         }
1248 out:
1249         btrfs_release_path(&path);
1250         if (ret < 0)
1251                 return ret;
1252         return has_parent ? 0 : 2;
1253 }
1254
1255 static int process_dir_item(struct btrfs_root *root,
1256                             struct extent_buffer *eb,
1257                             int slot, struct btrfs_key *key,
1258                             struct shared_node *active_node)
1259 {
1260         u32 total;
1261         u32 cur = 0;
1262         u32 len;
1263         u32 name_len;
1264         u32 data_len;
1265         int error;
1266         int nritems = 0;
1267         int filetype;
1268         struct btrfs_dir_item *di;
1269         struct inode_record *rec;
1270         struct cache_tree *root_cache;
1271         struct cache_tree *inode_cache;
1272         struct btrfs_key location;
1273         char namebuf[BTRFS_NAME_LEN];
1274
1275         root_cache = &active_node->root_cache;
1276         inode_cache = &active_node->inode_cache;
1277         rec = active_node->current;
1278         rec->found_dir_item = 1;
1279
1280         di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
1281         total = btrfs_item_size_nr(eb, slot);
1282         while (cur < total) {
1283                 nritems++;
1284                 btrfs_dir_item_key_to_cpu(eb, di, &location);
1285                 name_len = btrfs_dir_name_len(eb, di);
1286                 data_len = btrfs_dir_data_len(eb, di);
1287                 filetype = btrfs_dir_type(eb, di);
1288
1289                 rec->found_size += name_len;
1290                 if (name_len <= BTRFS_NAME_LEN) {
1291                         len = name_len;
1292                         error = 0;
1293                 } else {
1294                         len = BTRFS_NAME_LEN;
1295                         error = REF_ERR_NAME_TOO_LONG;
1296                 }
1297                 read_extent_buffer(eb, namebuf, (unsigned long)(di + 1), len);
1298
1299                 if (location.type == BTRFS_INODE_ITEM_KEY) {
1300                         add_inode_backref(inode_cache, location.objectid,
1301                                           key->objectid, key->offset, namebuf,
1302                                           len, filetype, key->type, error);
1303                 } else if (location.type == BTRFS_ROOT_ITEM_KEY) {
1304                         add_inode_backref(root_cache, location.objectid,
1305                                           key->objectid, key->offset,
1306                                           namebuf, len, filetype,
1307                                           key->type, error);
1308                 } else {
1309                         fprintf(stderr, "invalid location in dir item %u\n",
1310                                 location.type);
1311                         add_inode_backref(inode_cache, BTRFS_MULTIPLE_OBJECTIDS,
1312                                           key->objectid, key->offset, namebuf,
1313                                           len, filetype, key->type, error);
1314                 }
1315
1316                 len = sizeof(*di) + name_len + data_len;
1317                 di = (struct btrfs_dir_item *)((char *)di + len);
1318                 cur += len;
1319         }
1320         if (key->type == BTRFS_DIR_INDEX_KEY && nritems > 1)
1321                 rec->errors |= I_ERR_DUP_DIR_INDEX;
1322
1323         return 0;
1324 }
1325
1326 static int process_inode_ref(struct extent_buffer *eb,
1327                              int slot, struct btrfs_key *key,
1328                              struct shared_node *active_node)
1329 {
1330         u32 total;
1331         u32 cur = 0;
1332         u32 len;
1333         u32 name_len;
1334         u64 index;
1335         int error;
1336         struct cache_tree *inode_cache;
1337         struct btrfs_inode_ref *ref;
1338         char namebuf[BTRFS_NAME_LEN];
1339
1340         inode_cache = &active_node->inode_cache;
1341
1342         ref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref);
1343         total = btrfs_item_size_nr(eb, slot);
1344         while (cur < total) {
1345                 name_len = btrfs_inode_ref_name_len(eb, ref);
1346                 index = btrfs_inode_ref_index(eb, ref);
1347                 if (name_len <= BTRFS_NAME_LEN) {
1348                         len = name_len;
1349                         error = 0;
1350                 } else {
1351                         len = BTRFS_NAME_LEN;
1352                         error = REF_ERR_NAME_TOO_LONG;
1353                 }
1354                 read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
1355                 add_inode_backref(inode_cache, key->objectid, key->offset,
1356                                   index, namebuf, len, 0, key->type, error);
1357
1358                 len = sizeof(*ref) + name_len;
1359                 ref = (struct btrfs_inode_ref *)((char *)ref + len);
1360                 cur += len;
1361         }
1362         return 0;
1363 }
1364
1365 static int process_inode_extref(struct extent_buffer *eb,
1366                                 int slot, struct btrfs_key *key,
1367                                 struct shared_node *active_node)
1368 {
1369         u32 total;
1370         u32 cur = 0;
1371         u32 len;
1372         u32 name_len;
1373         u64 index;
1374         u64 parent;
1375         int error;
1376         struct cache_tree *inode_cache;
1377         struct btrfs_inode_extref *extref;
1378         char namebuf[BTRFS_NAME_LEN];
1379
1380         inode_cache = &active_node->inode_cache;
1381
1382         extref = btrfs_item_ptr(eb, slot, struct btrfs_inode_extref);
1383         total = btrfs_item_size_nr(eb, slot);
1384         while (cur < total) {
1385                 name_len = btrfs_inode_extref_name_len(eb, extref);
1386                 index = btrfs_inode_extref_index(eb, extref);
1387                 parent = btrfs_inode_extref_parent(eb, extref);
1388                 if (name_len <= BTRFS_NAME_LEN) {
1389                         len = name_len;
1390                         error = 0;
1391                 } else {
1392                         len = BTRFS_NAME_LEN;
1393                         error = REF_ERR_NAME_TOO_LONG;
1394                 }
1395                 read_extent_buffer(eb, namebuf,
1396                                    (unsigned long)(extref + 1), len);
1397                 add_inode_backref(inode_cache, key->objectid, parent,
1398                                   index, namebuf, len, 0, key->type, error);
1399
1400                 len = sizeof(*extref) + name_len;
1401                 extref = (struct btrfs_inode_extref *)((char *)extref + len);
1402                 cur += len;
1403         }
1404         return 0;
1405
1406 }
1407
1408 static int count_csum_range(struct btrfs_root *root, u64 start,
1409                             u64 len, u64 *found)
1410 {
1411         struct btrfs_key key;
1412         struct btrfs_path path;
1413         struct extent_buffer *leaf;
1414         int ret;
1415         size_t size;
1416         *found = 0;
1417         u64 csum_end;
1418         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
1419
1420         btrfs_init_path(&path);
1421
1422         key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
1423         key.offset = start;
1424         key.type = BTRFS_EXTENT_CSUM_KEY;
1425
1426         ret = btrfs_search_slot(NULL, root->fs_info->csum_root,
1427                                 &key, &path, 0, 0);
1428         if (ret < 0)
1429                 goto out;
1430         if (ret > 0 && path.slots[0] > 0) {
1431                 leaf = path.nodes[0];
1432                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0] - 1);
1433                 if (key.objectid == BTRFS_EXTENT_CSUM_OBJECTID &&
1434                     key.type == BTRFS_EXTENT_CSUM_KEY)
1435                         path.slots[0]--;
1436         }
1437
1438         while (len > 0) {
1439                 leaf = path.nodes[0];
1440                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
1441                         ret = btrfs_next_leaf(root->fs_info->csum_root, &path);
1442                         if (ret > 0)
1443                                 break;
1444                         else if (ret < 0)
1445                                 goto out;
1446                         leaf = path.nodes[0];
1447                 }
1448
1449                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1450                 if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
1451                     key.type != BTRFS_EXTENT_CSUM_KEY)
1452                         break;
1453
1454                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1455                 if (key.offset >= start + len)
1456                         break;
1457
1458                 if (key.offset > start)
1459                         start = key.offset;
1460
1461                 size = btrfs_item_size_nr(leaf, path.slots[0]);
1462                 csum_end = key.offset + (size / csum_size) * root->sectorsize;
1463                 if (csum_end > start) {
1464                         size = min(csum_end - start, len);
1465                         len -= size;
1466                         start += size;
1467                         *found += size;
1468                 }
1469
1470                 path.slots[0]++;
1471         }
1472 out:
1473         btrfs_release_path(&path);
1474         if (ret < 0)
1475                 return ret;
1476         return 0;
1477 }
1478
1479 static int process_file_extent(struct btrfs_root *root,
1480                                 struct extent_buffer *eb,
1481                                 int slot, struct btrfs_key *key,
1482                                 struct shared_node *active_node)
1483 {
1484         struct inode_record *rec;
1485         struct btrfs_file_extent_item *fi;
1486         u64 num_bytes = 0;
1487         u64 disk_bytenr = 0;
1488         u64 extent_offset = 0;
1489         u64 mask = root->sectorsize - 1;
1490         int extent_type;
1491         int ret;
1492
1493         rec = active_node->current;
1494         BUG_ON(rec->ino != key->objectid || rec->refs > 1);
1495         rec->found_file_extent = 1;
1496
1497         if (rec->extent_start == (u64)-1) {
1498                 rec->extent_start = key->offset;
1499                 rec->extent_end = key->offset;
1500         }
1501
1502         if (rec->extent_end > key->offset)
1503                 rec->errors |= I_ERR_FILE_EXTENT_OVERLAP;
1504         else if (rec->extent_end < key->offset) {
1505                 ret = add_file_extent_hole(&rec->holes, rec->extent_end,
1506                                            key->offset - rec->extent_end);
1507                 if (ret < 0)
1508                         return ret;
1509         }
1510
1511         fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
1512         extent_type = btrfs_file_extent_type(eb, fi);
1513
1514         if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1515                 num_bytes = btrfs_file_extent_inline_len(eb, slot, fi);
1516                 if (num_bytes == 0)
1517                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1518                 rec->found_size += num_bytes;
1519                 num_bytes = (num_bytes + mask) & ~mask;
1520         } else if (extent_type == BTRFS_FILE_EXTENT_REG ||
1521                    extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1522                 num_bytes = btrfs_file_extent_num_bytes(eb, fi);
1523                 disk_bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
1524                 extent_offset = btrfs_file_extent_offset(eb, fi);
1525                 if (num_bytes == 0 || (num_bytes & mask))
1526                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1527                 if (num_bytes + extent_offset >
1528                     btrfs_file_extent_ram_bytes(eb, fi))
1529                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1530                 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC &&
1531                     (btrfs_file_extent_compression(eb, fi) ||
1532                      btrfs_file_extent_encryption(eb, fi) ||
1533                      btrfs_file_extent_other_encoding(eb, fi)))
1534                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
1535                 if (disk_bytenr > 0)
1536                         rec->found_size += num_bytes;
1537         } else {
1538                 rec->errors |= I_ERR_BAD_FILE_EXTENT;
1539         }
1540         rec->extent_end = key->offset + num_bytes;
1541
1542         /*
1543          * The data reloc tree will copy full extents into its inode and then
1544          * copy the corresponding csums.  Because the extent it copied could be
1545          * a preallocated extent that hasn't been written to yet there may be no
1546          * csums to copy, ergo we won't have csums for our file extent.  This is
1547          * ok so just don't bother checking csums if the inode belongs to the
1548          * data reloc tree.
1549          */
1550         if (disk_bytenr > 0 &&
1551             btrfs_header_owner(eb) != BTRFS_DATA_RELOC_TREE_OBJECTID) {
1552                 u64 found;
1553                 if (btrfs_file_extent_compression(eb, fi))
1554                         num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
1555                 else
1556                         disk_bytenr += extent_offset;
1557
1558                 ret = count_csum_range(root, disk_bytenr, num_bytes, &found);
1559                 if (ret < 0)
1560                         return ret;
1561                 if (extent_type == BTRFS_FILE_EXTENT_REG) {
1562                         if (found > 0)
1563                                 rec->found_csum_item = 1;
1564                         if (found < num_bytes)
1565                                 rec->some_csum_missing = 1;
1566                 } else if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1567                         if (found > 0)
1568                                 rec->errors |= I_ERR_ODD_CSUM_ITEM;
1569                 }
1570         }
1571         return 0;
1572 }
1573
1574 static int process_one_leaf(struct btrfs_root *root, struct extent_buffer *eb,
1575                             struct walk_control *wc)
1576 {
1577         struct btrfs_key key;
1578         u32 nritems;
1579         int i;
1580         int ret = 0;
1581         struct cache_tree *inode_cache;
1582         struct shared_node *active_node;
1583
1584         if (wc->root_level == wc->active_node &&
1585             btrfs_root_refs(&root->root_item) == 0)
1586                 return 0;
1587
1588         active_node = wc->nodes[wc->active_node];
1589         inode_cache = &active_node->inode_cache;
1590         nritems = btrfs_header_nritems(eb);
1591         for (i = 0; i < nritems; i++) {
1592                 btrfs_item_key_to_cpu(eb, &key, i);
1593
1594                 if (key.objectid == BTRFS_FREE_SPACE_OBJECTID)
1595                         continue;
1596                 if (key.type == BTRFS_ORPHAN_ITEM_KEY)
1597                         continue;
1598
1599                 if (active_node->current == NULL ||
1600                     active_node->current->ino < key.objectid) {
1601                         if (active_node->current) {
1602                                 active_node->current->checked = 1;
1603                                 maybe_free_inode_rec(inode_cache,
1604                                                      active_node->current);
1605                         }
1606                         active_node->current = get_inode_rec(inode_cache,
1607                                                              key.objectid, 1);
1608                 }
1609                 switch (key.type) {
1610                 case BTRFS_DIR_ITEM_KEY:
1611                 case BTRFS_DIR_INDEX_KEY:
1612                         ret = process_dir_item(root, eb, i, &key, active_node);
1613                         break;
1614                 case BTRFS_INODE_REF_KEY:
1615                         ret = process_inode_ref(eb, i, &key, active_node);
1616                         break;
1617                 case BTRFS_INODE_EXTREF_KEY:
1618                         ret = process_inode_extref(eb, i, &key, active_node);
1619                         break;
1620                 case BTRFS_INODE_ITEM_KEY:
1621                         ret = process_inode_item(eb, i, &key, active_node);
1622                         break;
1623                 case BTRFS_EXTENT_DATA_KEY:
1624                         ret = process_file_extent(root, eb, i, &key,
1625                                                   active_node);
1626                         break;
1627                 default:
1628                         break;
1629                 };
1630         }
1631         return ret;
1632 }
1633
1634 static void reada_walk_down(struct btrfs_root *root,
1635                             struct extent_buffer *node, int slot)
1636 {
1637         u64 bytenr;
1638         u64 ptr_gen;
1639         u32 nritems;
1640         u32 blocksize;
1641         int i;
1642         int level;
1643
1644         level = btrfs_header_level(node);
1645         if (level != 1)
1646                 return;
1647
1648         nritems = btrfs_header_nritems(node);
1649         blocksize = btrfs_level_size(root, level - 1);
1650         for (i = slot; i < nritems; i++) {
1651                 bytenr = btrfs_node_blockptr(node, i);
1652                 ptr_gen = btrfs_node_ptr_generation(node, i);
1653                 readahead_tree_block(root, bytenr, blocksize, ptr_gen);
1654         }
1655 }
1656
1657 /*
1658  * Check the child node/leaf by the following condition:
1659  * 1. the first item key of the node/leaf should be the same with the one
1660  *    in parent.
1661  * 2. block in parent node should match the child node/leaf.
1662  * 3. generation of parent node and child's header should be consistent.
1663  *
1664  * Or the child node/leaf pointed by the key in parent is not valid.
1665  *
1666  * We hope to check leaf owner too, but since subvol may share leaves,
1667  * which makes leaf owner check not so strong, key check should be
1668  * sufficient enough for that case.
1669  */
1670 static int check_child_node(struct btrfs_root *root,
1671                             struct extent_buffer *parent, int slot,
1672                             struct extent_buffer *child)
1673 {
1674         struct btrfs_key parent_key;
1675         struct btrfs_key child_key;
1676         int ret = 0;
1677
1678         btrfs_node_key_to_cpu(parent, &parent_key, slot);
1679         if (btrfs_header_level(child) == 0)
1680                 btrfs_item_key_to_cpu(child, &child_key, 0);
1681         else
1682                 btrfs_node_key_to_cpu(child, &child_key, 0);
1683
1684         if (memcmp(&parent_key, &child_key, sizeof(parent_key))) {
1685                 ret = -EINVAL;
1686                 fprintf(stderr,
1687                         "Wrong key of child node/leaf, wanted: (%llu, %u, %llu), have: (%llu, %u, %llu)\n",
1688                         parent_key.objectid, parent_key.type, parent_key.offset,
1689                         child_key.objectid, child_key.type, child_key.offset);
1690         }
1691         if (btrfs_header_bytenr(child) != btrfs_node_blockptr(parent, slot)) {
1692                 ret = -EINVAL;
1693                 fprintf(stderr, "Wrong block of child node/leaf, wanted: %llu, have: %llu\n",
1694                         btrfs_node_blockptr(parent, slot),
1695                         btrfs_header_bytenr(child));
1696         }
1697         if (btrfs_node_ptr_generation(parent, slot) !=
1698             btrfs_header_generation(child)) {
1699                 ret = -EINVAL;
1700                 fprintf(stderr, "Wrong generation of child node/leaf, wanted: %llu, have: %llu\n",
1701                         btrfs_header_generation(child),
1702                         btrfs_node_ptr_generation(parent, slot));
1703         }
1704         return ret;
1705 }
1706
1707 static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
1708                           struct walk_control *wc, int *level)
1709 {
1710         enum btrfs_tree_block_status status;
1711         u64 bytenr;
1712         u64 ptr_gen;
1713         struct extent_buffer *next;
1714         struct extent_buffer *cur;
1715         u32 blocksize;
1716         int ret, err = 0;
1717         u64 refs;
1718
1719         WARN_ON(*level < 0);
1720         WARN_ON(*level >= BTRFS_MAX_LEVEL);
1721         ret = btrfs_lookup_extent_info(NULL, root,
1722                                        path->nodes[*level]->start,
1723                                        *level, 1, &refs, NULL);
1724         if (ret < 0) {
1725                 err = ret;
1726                 goto out;
1727         }
1728
1729         if (refs > 1) {
1730                 ret = enter_shared_node(root, path->nodes[*level]->start,
1731                                         refs, wc, *level);
1732                 if (ret > 0) {
1733                         err = ret;
1734                         goto out;
1735                 }
1736         }
1737
1738         while (*level >= 0) {
1739                 WARN_ON(*level < 0);
1740                 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1741                 cur = path->nodes[*level];
1742
1743                 if (btrfs_header_level(cur) != *level)
1744                         WARN_ON(1);
1745
1746                 if (path->slots[*level] >= btrfs_header_nritems(cur))
1747                         break;
1748                 if (*level == 0) {
1749                         ret = process_one_leaf(root, cur, wc);
1750                         if (ret < 0)
1751                                 err = ret;
1752                         break;
1753                 }
1754                 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1755                 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1756                 blocksize = btrfs_level_size(root, *level - 1);
1757                 ret = btrfs_lookup_extent_info(NULL, root, bytenr, *level - 1,
1758                                                1, &refs, NULL);
1759                 if (ret < 0)
1760                         refs = 0;
1761
1762                 if (refs > 1) {
1763                         ret = enter_shared_node(root, bytenr, refs,
1764                                                 wc, *level - 1);
1765                         if (ret > 0) {
1766                                 path->slots[*level]++;
1767                                 continue;
1768                         }
1769                 }
1770
1771                 next = btrfs_find_tree_block(root, bytenr, blocksize);
1772                 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
1773                         free_extent_buffer(next);
1774                         reada_walk_down(root, cur, path->slots[*level]);
1775                         next = read_tree_block(root, bytenr, blocksize,
1776                                                ptr_gen);
1777                         if (!extent_buffer_uptodate(next)) {
1778                                 struct btrfs_key node_key;
1779
1780                                 btrfs_node_key_to_cpu(path->nodes[*level],
1781                                                       &node_key,
1782                                                       path->slots[*level]);
1783                                 btrfs_add_corrupt_extent_record(root->fs_info,
1784                                                 &node_key,
1785                                                 path->nodes[*level]->start,
1786                                                 root->leafsize, *level);
1787                                 err = -EIO;
1788                                 goto out;
1789                         }
1790                 }
1791
1792                 ret = check_child_node(root, cur, path->slots[*level], next);
1793                 if (ret) {
1794                         err = ret;
1795                         goto out;
1796                 }
1797
1798                 if (btrfs_is_leaf(next))
1799                         status = btrfs_check_leaf(root, NULL, next);
1800                 else
1801                         status = btrfs_check_node(root, NULL, next);
1802                 if (status != BTRFS_TREE_BLOCK_CLEAN) {
1803                         free_extent_buffer(next);
1804                         err = -EIO;
1805                         goto out;
1806                 }
1807
1808                 *level = *level - 1;
1809                 free_extent_buffer(path->nodes[*level]);
1810                 path->nodes[*level] = next;
1811                 path->slots[*level] = 0;
1812         }
1813 out:
1814         path->slots[*level] = btrfs_header_nritems(path->nodes[*level]);
1815         return err;
1816 }
1817
1818 static int walk_up_tree(struct btrfs_root *root, struct btrfs_path *path,
1819                         struct walk_control *wc, int *level)
1820 {
1821         int i;
1822         struct extent_buffer *leaf;
1823
1824         for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1825                 leaf = path->nodes[i];
1826                 if (path->slots[i] + 1 < btrfs_header_nritems(leaf)) {
1827                         path->slots[i]++;
1828                         *level = i;
1829                         return 0;
1830                 } else {
1831                         free_extent_buffer(path->nodes[*level]);
1832                         path->nodes[*level] = NULL;
1833                         BUG_ON(*level > wc->active_node);
1834                         if (*level == wc->active_node)
1835                                 leave_shared_node(root, wc, *level);
1836                         *level = i + 1;
1837                 }
1838         }
1839         return 1;
1840 }
1841
1842 static int check_root_dir(struct inode_record *rec)
1843 {
1844         struct inode_backref *backref;
1845         int ret = -1;
1846
1847         if (!rec->found_inode_item || rec->errors)
1848                 goto out;
1849         if (rec->nlink != 1 || rec->found_link != 0)
1850                 goto out;
1851         if (list_empty(&rec->backrefs))
1852                 goto out;
1853         backref = list_entry(rec->backrefs.next, struct inode_backref, list);
1854         if (!backref->found_inode_ref)
1855                 goto out;
1856         if (backref->index != 0 || backref->namelen != 2 ||
1857             memcmp(backref->name, "..", 2))
1858                 goto out;
1859         if (backref->found_dir_index || backref->found_dir_item)
1860                 goto out;
1861         ret = 0;
1862 out:
1863         return ret;
1864 }
1865
1866 static int repair_inode_isize(struct btrfs_trans_handle *trans,
1867                               struct btrfs_root *root, struct btrfs_path *path,
1868                               struct inode_record *rec)
1869 {
1870         struct btrfs_inode_item *ei;
1871         struct btrfs_key key;
1872         int ret;
1873
1874         key.objectid = rec->ino;
1875         key.type = BTRFS_INODE_ITEM_KEY;
1876         key.offset = (u64)-1;
1877
1878         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1879         if (ret < 0)
1880                 goto out;
1881         if (ret) {
1882                 if (!path->slots[0]) {
1883                         ret = -ENOENT;
1884                         goto out;
1885                 }
1886                 path->slots[0]--;
1887                 ret = 0;
1888         }
1889         btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1890         if (key.objectid != rec->ino) {
1891                 ret = -ENOENT;
1892                 goto out;
1893         }
1894
1895         ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
1896                             struct btrfs_inode_item);
1897         btrfs_set_inode_size(path->nodes[0], ei, rec->found_size);
1898         btrfs_mark_buffer_dirty(path->nodes[0]);
1899         rec->errors &= ~I_ERR_DIR_ISIZE_WRONG;
1900         printf("reset isize for dir %Lu root %Lu\n", rec->ino,
1901                root->root_key.objectid);
1902 out:
1903         btrfs_release_path(path);
1904         return ret;
1905 }
1906
1907 static int repair_inode_orphan_item(struct btrfs_trans_handle *trans,
1908                                     struct btrfs_root *root,
1909                                     struct btrfs_path *path,
1910                                     struct inode_record *rec)
1911 {
1912         int ret;
1913
1914         ret = btrfs_add_orphan_item(trans, root, path, rec->ino);
1915         btrfs_release_path(path);
1916         if (!ret)
1917                 rec->errors &= ~I_ERR_NO_ORPHAN_ITEM;
1918         return ret;
1919 }
1920
1921 static int add_missing_dir_index(struct btrfs_root *root,
1922                                  struct cache_tree *inode_cache,
1923                                  struct inode_record *rec,
1924                                  struct inode_backref *backref)
1925 {
1926         struct btrfs_path *path;
1927         struct btrfs_trans_handle *trans;
1928         struct btrfs_dir_item *dir_item;
1929         struct extent_buffer *leaf;
1930         struct btrfs_key key;
1931         struct btrfs_disk_key disk_key;
1932         struct inode_record *dir_rec;
1933         unsigned long name_ptr;
1934         u32 data_size = sizeof(*dir_item) + backref->namelen;
1935         int ret;
1936
1937         path = btrfs_alloc_path();
1938         if (!path)
1939                 return -ENOMEM;
1940
1941         trans = btrfs_start_transaction(root, 1);
1942         if (IS_ERR(trans)) {
1943                 btrfs_free_path(path);
1944                 return PTR_ERR(trans);
1945         }
1946
1947         fprintf(stderr, "repairing missing dir index item for inode %llu\n",
1948                 (unsigned long long)rec->ino);
1949         key.objectid = backref->dir;
1950         key.type = BTRFS_DIR_INDEX_KEY;
1951         key.offset = backref->index;
1952
1953         ret = btrfs_insert_empty_item(trans, root, path, &key, data_size);
1954         BUG_ON(ret);
1955
1956         leaf = path->nodes[0];
1957         dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);
1958
1959         disk_key.objectid = cpu_to_le64(rec->ino);
1960         disk_key.type = BTRFS_INODE_ITEM_KEY;
1961         disk_key.offset = 0;
1962
1963         btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
1964         btrfs_set_dir_type(leaf, dir_item, imode_to_type(rec->imode));
1965         btrfs_set_dir_data_len(leaf, dir_item, 0);
1966         btrfs_set_dir_name_len(leaf, dir_item, backref->namelen);
1967         name_ptr = (unsigned long)(dir_item + 1);
1968         write_extent_buffer(leaf, backref->name, name_ptr, backref->namelen);
1969         btrfs_mark_buffer_dirty(leaf);
1970         btrfs_free_path(path);
1971         btrfs_commit_transaction(trans, root);
1972
1973         backref->found_dir_index = 1;
1974         dir_rec = get_inode_rec(inode_cache, backref->dir, 0);
1975         if (!dir_rec)
1976                 return 0;
1977         dir_rec->found_size += backref->namelen;
1978         if (dir_rec->found_size == dir_rec->isize &&
1979             (dir_rec->errors & I_ERR_DIR_ISIZE_WRONG))
1980                 dir_rec->errors &= ~I_ERR_DIR_ISIZE_WRONG;
1981         if (dir_rec->found_size != dir_rec->isize)
1982                 dir_rec->errors |= I_ERR_DIR_ISIZE_WRONG;
1983
1984         return 0;
1985 }
1986
1987 static int delete_dir_index(struct btrfs_root *root,
1988                             struct cache_tree *inode_cache,
1989                             struct inode_record *rec,
1990                             struct inode_backref *backref)
1991 {
1992         struct btrfs_trans_handle *trans;
1993         struct btrfs_dir_item *di;
1994         struct btrfs_path *path;
1995         int ret = 0;
1996
1997         path = btrfs_alloc_path();
1998         if (!path)
1999                 return -ENOMEM;
2000
2001         trans = btrfs_start_transaction(root, 1);
2002         if (IS_ERR(trans)) {
2003                 btrfs_free_path(path);
2004                 return PTR_ERR(trans);
2005         }
2006
2007
2008         fprintf(stderr, "Deleting bad dir index [%llu,%u,%llu] root %llu\n",
2009                 (unsigned long long)backref->dir,
2010                 BTRFS_DIR_INDEX_KEY, (unsigned long long)backref->index,
2011                 (unsigned long long)root->objectid);
2012
2013         di = btrfs_lookup_dir_index(trans, root, path, backref->dir,
2014                                     backref->name, backref->namelen,
2015                                     backref->index, -1);
2016         if (IS_ERR(di)) {
2017                 ret = PTR_ERR(di);
2018                 btrfs_free_path(path);
2019                 btrfs_commit_transaction(trans, root);
2020                 if (ret == -ENOENT)
2021                         return 0;
2022                 return ret;
2023         }
2024
2025         if (!di)
2026                 ret = btrfs_del_item(trans, root, path);
2027         else
2028                 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2029         BUG_ON(ret);
2030         btrfs_free_path(path);
2031         btrfs_commit_transaction(trans, root);
2032         return ret;
2033 }
2034
2035 static int create_inode_item(struct btrfs_root *root,
2036                              struct inode_record *rec,
2037                              struct inode_backref *backref, int root_dir)
2038 {
2039         struct btrfs_trans_handle *trans;
2040         struct btrfs_inode_item inode_item;
2041         time_t now = time(NULL);
2042         int ret;
2043
2044         trans = btrfs_start_transaction(root, 1);
2045         if (IS_ERR(trans)) {
2046                 ret = PTR_ERR(trans);
2047                 return ret;
2048         }
2049
2050         fprintf(stderr, "root %llu inode %llu recreating inode item, this may "
2051                 "be incomplete, please check permissions and content after "
2052                 "the fsck completes.\n", (unsigned long long)root->objectid,
2053                 (unsigned long long)rec->ino);
2054
2055         memset(&inode_item, 0, sizeof(inode_item));
2056         btrfs_set_stack_inode_generation(&inode_item, trans->transid);
2057         if (root_dir)
2058                 btrfs_set_stack_inode_nlink(&inode_item, 1);
2059         else
2060                 btrfs_set_stack_inode_nlink(&inode_item, rec->found_link);
2061         btrfs_set_stack_inode_nbytes(&inode_item, rec->found_size);
2062         if (rec->found_dir_item) {
2063                 if (rec->found_file_extent)
2064                         fprintf(stderr, "root %llu inode %llu has both a dir "
2065                                 "item and extents, unsure if it is a dir or a "
2066                                 "regular file so setting it as a directory\n",
2067                                 (unsigned long long)root->objectid,
2068                                 (unsigned long long)rec->ino);
2069                 btrfs_set_stack_inode_mode(&inode_item, S_IFDIR | 0755);
2070                 btrfs_set_stack_inode_size(&inode_item, rec->found_size);
2071         } else if (!rec->found_dir_item) {
2072                 btrfs_set_stack_inode_size(&inode_item, rec->extent_end);
2073                 btrfs_set_stack_inode_mode(&inode_item, S_IFREG | 0755);
2074         }
2075         btrfs_set_stack_timespec_sec(&inode_item.atime, now);
2076         btrfs_set_stack_timespec_nsec(&inode_item.atime, 0);
2077         btrfs_set_stack_timespec_sec(&inode_item.ctime, now);
2078         btrfs_set_stack_timespec_nsec(&inode_item.ctime, 0);
2079         btrfs_set_stack_timespec_sec(&inode_item.mtime, now);
2080         btrfs_set_stack_timespec_nsec(&inode_item.mtime, 0);
2081         btrfs_set_stack_timespec_sec(&inode_item.otime, 0);
2082         btrfs_set_stack_timespec_nsec(&inode_item.otime, 0);
2083
2084         ret = btrfs_insert_inode(trans, root, rec->ino, &inode_item);
2085         BUG_ON(ret);
2086         btrfs_commit_transaction(trans, root);
2087         return 0;
2088 }
2089
2090 static int repair_inode_backrefs(struct btrfs_root *root,
2091                                  struct inode_record *rec,
2092                                  struct cache_tree *inode_cache,
2093                                  int delete)
2094 {
2095         struct inode_backref *tmp, *backref;
2096         u64 root_dirid = btrfs_root_dirid(&root->root_item);
2097         int ret = 0;
2098         int repaired = 0;
2099
2100         list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
2101                 if (!delete && rec->ino == root_dirid) {
2102                         if (!rec->found_inode_item) {
2103                                 ret = create_inode_item(root, rec, backref, 1);
2104                                 if (ret)
2105                                         break;
2106                                 repaired++;
2107                         }
2108                 }
2109
2110                 /* Index 0 for root dir's are special, don't mess with it */
2111                 if (rec->ino == root_dirid && backref->index == 0)
2112                         continue;
2113
2114                 if (delete &&
2115                     ((backref->found_dir_index && !backref->found_inode_ref) ||
2116                      (backref->found_dir_index && backref->found_inode_ref &&
2117                       (backref->errors & REF_ERR_INDEX_UNMATCH)))) {
2118                         ret = delete_dir_index(root, inode_cache, rec, backref);
2119                         if (ret)
2120                                 break;
2121                         repaired++;
2122                         list_del(&backref->list);
2123                         free(backref);
2124                 }
2125
2126                 if (!delete && !backref->found_dir_index &&
2127                     backref->found_dir_item && backref->found_inode_ref) {
2128                         ret = add_missing_dir_index(root, inode_cache, rec,
2129                                                     backref);
2130                         if (ret)
2131                                 break;
2132                         repaired++;
2133                         if (backref->found_dir_item &&
2134                             backref->found_dir_index &&
2135                             backref->found_dir_index) {
2136                                 if (!backref->errors &&
2137                                     backref->found_inode_ref) {
2138                                         list_del(&backref->list);
2139                                         free(backref);
2140                                 }
2141                         }
2142                 }
2143
2144                 if (!delete && (!backref->found_dir_index &&
2145                                 !backref->found_dir_item &&
2146                                 backref->found_inode_ref)) {
2147                         struct btrfs_trans_handle *trans;
2148                         struct btrfs_key location;
2149
2150                         ret = check_dir_conflict(root, backref->name,
2151                                                  backref->namelen,
2152                                                  backref->dir,
2153                                                  backref->index);
2154                         if (ret) {
2155                                 /*
2156                                  * let nlink fixing routine to handle it,
2157                                  * which can do it better.
2158                                  */
2159                                 ret = 0;
2160                                 break;
2161                         }
2162                         location.objectid = rec->ino;
2163                         location.type = BTRFS_INODE_ITEM_KEY;
2164                         location.offset = 0;
2165
2166                         trans = btrfs_start_transaction(root, 1);
2167                         if (IS_ERR(trans)) {
2168                                 ret = PTR_ERR(trans);
2169                                 break;
2170                         }
2171                         fprintf(stderr, "adding missing dir index/item pair "
2172                                 "for inode %llu\n",
2173                                 (unsigned long long)rec->ino);
2174                         ret = btrfs_insert_dir_item(trans, root, backref->name,
2175                                                     backref->namelen,
2176                                                     backref->dir, &location,
2177                                                     imode_to_type(rec->imode),
2178                                                     backref->index);
2179                         BUG_ON(ret);
2180                         btrfs_commit_transaction(trans, root);
2181                         repaired++;
2182                 }
2183
2184                 if (!delete && (backref->found_inode_ref &&
2185                                 backref->found_dir_index &&
2186                                 backref->found_dir_item &&
2187                                 !(backref->errors & REF_ERR_INDEX_UNMATCH) &&
2188                                 !rec->found_inode_item)) {
2189                         ret = create_inode_item(root, rec, backref, 0);
2190                         if (ret)
2191                                 break;
2192                         repaired++;
2193                 }
2194
2195         }
2196         return ret ? ret : repaired;
2197 }
2198
2199 /*
2200  * To determine the file type for nlink/inode_item repair
2201  *
2202  * Return 0 if file type is found and BTRFS_FT_* is stored into type.
2203  * Return -ENOENT if file type is not found.
2204  */
2205 static int find_file_type(struct inode_record *rec, u8 *type)
2206 {
2207         struct inode_backref *backref;
2208
2209         /* For inode item recovered case */
2210         if (rec->found_inode_item) {
2211                 *type = imode_to_type(rec->imode);
2212                 return 0;
2213         }
2214
2215         list_for_each_entry(backref, &rec->backrefs, list) {
2216                 if (backref->found_dir_index || backref->found_dir_item) {
2217                         *type = backref->filetype;
2218                         return 0;
2219                 }
2220         }
2221         return -ENOENT;
2222 }
2223
2224 /*
2225  * To determine the file name for nlink repair
2226  *
2227  * Return 0 if file name is found, set name and namelen.
2228  * Return -ENOENT if file name is not found.
2229  */
2230 static int find_file_name(struct inode_record *rec,
2231                           char *name, int *namelen)
2232 {
2233         struct inode_backref *backref;
2234
2235         list_for_each_entry(backref, &rec->backrefs, list) {
2236                 if (backref->found_dir_index || backref->found_dir_item ||
2237                     backref->found_inode_ref) {
2238                         memcpy(name, backref->name, backref->namelen);
2239                         *namelen = backref->namelen;
2240                         return 0;
2241                 }
2242         }
2243         return -ENOENT;
2244 }
2245
2246 /* Reset the nlink of the inode to the correct one */
2247 static int reset_nlink(struct btrfs_trans_handle *trans,
2248                        struct btrfs_root *root,
2249                        struct btrfs_path *path,
2250                        struct inode_record *rec)
2251 {
2252         struct inode_backref *backref;
2253         struct inode_backref *tmp;
2254         struct btrfs_key key;
2255         struct btrfs_inode_item *inode_item;
2256         int ret = 0;
2257
2258         /* We don't believe this either, reset it and iterate backref */
2259         rec->found_link = 0;
2260
2261         /* Remove all backref including the valid ones */
2262         list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
2263                 ret = btrfs_unlink(trans, root, rec->ino, backref->dir,
2264                                    backref->index, backref->name,
2265                                    backref->namelen, 0);
2266                 if (ret < 0)
2267                         goto out;
2268
2269                 /* remove invalid backref, so it won't be added back */
2270                 if (!(backref->found_dir_index &&
2271                       backref->found_dir_item &&
2272                       backref->found_inode_ref)) {
2273                         list_del(&backref->list);
2274                         free(backref);
2275                 } else {
2276                         rec->found_link++;
2277                 }
2278         }
2279
2280         /* Set nlink to 0 */
2281         key.objectid = rec->ino;
2282         key.type = BTRFS_INODE_ITEM_KEY;
2283         key.offset = 0;
2284         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2285         if (ret < 0)
2286                 goto out;
2287         if (ret > 0) {
2288                 ret = -ENOENT;
2289                 goto out;
2290         }
2291         inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2292                                     struct btrfs_inode_item);
2293         btrfs_set_inode_nlink(path->nodes[0], inode_item, 0);
2294         btrfs_mark_buffer_dirty(path->nodes[0]);
2295         btrfs_release_path(path);
2296
2297         /*
2298          * Add back valid inode_ref/dir_item/dir_index,
2299          * add_link() will handle the nlink inc, so new nlink must be correct
2300          */
2301         list_for_each_entry(backref, &rec->backrefs, list) {
2302                 ret = btrfs_add_link(trans, root, rec->ino, backref->dir,
2303                                      backref->name, backref->namelen,
2304                                      backref->ref_type, &backref->index, 1);
2305                 if (ret < 0)
2306                         goto out;
2307         }
2308 out:
2309         btrfs_release_path(path);
2310         return ret;
2311 }
2312
2313 static int repair_inode_nlinks(struct btrfs_trans_handle *trans,
2314                                struct btrfs_root *root,
2315                                struct btrfs_path *path,
2316                                struct inode_record *rec)
2317 {
2318         char *dir_name = "lost+found";
2319         char namebuf[BTRFS_NAME_LEN] = {0};
2320         u64 lost_found_ino;
2321         u32 mode = 0700;
2322         u8 type = 0;
2323         int namelen = 0;
2324         int name_recovered = 0;
2325         int type_recovered = 0;
2326         int ret = 0;
2327
2328         /*
2329          * Get file name and type first before these invalid inode ref
2330          * are deleted by remove_all_invalid_backref()
2331          */
2332         name_recovered = !find_file_name(rec, namebuf, &namelen);
2333         type_recovered = !find_file_type(rec, &type);
2334
2335         if (!name_recovered) {
2336                 printf("Can't get file name for inode %llu, using '%llu' as fallback\n",
2337                        rec->ino, rec->ino);
2338                 namelen = count_digits(rec->ino);
2339                 sprintf(namebuf, "%llu", rec->ino);
2340                 name_recovered = 1;
2341         }
2342         if (!type_recovered) {
2343                 printf("Can't get file type for inode %llu, using FILE as fallback\n",
2344                        rec->ino);
2345                 type = BTRFS_FT_REG_FILE;
2346                 type_recovered = 1;
2347         }
2348
2349         ret = reset_nlink(trans, root, path, rec);
2350         if (ret < 0) {
2351                 fprintf(stderr,
2352                         "Failed to reset nlink for inode %llu: %s\n",
2353                         rec->ino, strerror(-ret));
2354                 goto out;
2355         }
2356
2357         if (rec->found_link == 0) {
2358                 lost_found_ino = root->highest_inode;
2359                 if (lost_found_ino >= BTRFS_LAST_FREE_OBJECTID) {
2360                         ret = -EOVERFLOW;
2361                         goto out;
2362                 }
2363                 lost_found_ino++;
2364                 ret = btrfs_mkdir(trans, root, dir_name, strlen(dir_name),
2365                                   BTRFS_FIRST_FREE_OBJECTID, &lost_found_ino,
2366                                   mode);
2367                 if (ret < 0) {
2368                         fprintf(stderr, "Failed to create '%s' dir: %s",
2369                                 dir_name, strerror(-ret));
2370                         goto out;
2371                 }
2372                 ret = btrfs_add_link(trans, root, rec->ino, lost_found_ino,
2373                                      namebuf, namelen, type, NULL, 1);
2374                 /*
2375                  * Add ".INO" suffix several times to handle case where
2376                  * "FILENAME.INO" is already taken by another file.
2377                  */
2378                 while (ret == -EEXIST) {
2379                         /*
2380                          * Conflicting file name, add ".INO" as suffix * +1 for '.'
2381                          */
2382                         if (namelen + count_digits(rec->ino) + 1 >
2383                             BTRFS_NAME_LEN) {
2384                                 ret = -EFBIG;
2385                                 goto out;
2386                         }
2387                         snprintf(namebuf + namelen, BTRFS_NAME_LEN - namelen,
2388                                  ".%llu", rec->ino);
2389                         namelen += count_digits(rec->ino) + 1;
2390                         ret = btrfs_add_link(trans, root, rec->ino,
2391                                              lost_found_ino, namebuf,
2392                                              namelen, type, NULL, 1);
2393                 }
2394                 if (ret < 0) {
2395                         fprintf(stderr,
2396                                 "Failed to link the inode %llu to %s dir: %s",
2397                                 rec->ino, dir_name, strerror(-ret));
2398                         goto out;
2399                 }
2400                 /*
2401                  * Just increase the found_link, don't actually add the
2402                  * backref. This will make things easier and this inode
2403                  * record will be freed after the repair is done.
2404                  * So fsck will not report problem about this inode.
2405                  */
2406                 rec->found_link++;
2407                 printf("Moving file '%.*s' to '%s' dir since it has no valid backref\n",
2408                        namelen, namebuf, dir_name);
2409         }
2410         printf("Fixed the nlink of inode %llu\n", rec->ino);
2411 out:
2412         /*
2413          * Clear the flag anyway, or we will loop forever for the same inode
2414          * as it will not be removed from the bad inode list and the dead loop
2415          * happens.
2416          */
2417         rec->errors &= ~I_ERR_LINK_COUNT_WRONG;
2418         btrfs_release_path(path);
2419         return ret;
2420 }
2421
2422 /*
2423  * Check if there is any normal(reg or prealloc) file extent for given
2424  * ino.
2425  * This is used to determine the file type when neither its dir_index/item or
2426  * inode_item exists.
2427  *
2428  * This will *NOT* report error, if any error happens, just consider it does
2429  * not have any normal file extent.
2430  */
2431 static int find_normal_file_extent(struct btrfs_root *root, u64 ino)
2432 {
2433         struct btrfs_path *path;
2434         struct btrfs_key key;
2435         struct btrfs_key found_key;
2436         struct btrfs_file_extent_item *fi;
2437         u8 type;
2438         int ret = 0;
2439
2440         path = btrfs_alloc_path();
2441         if (!path)
2442                 goto out;
2443         key.objectid = ino;
2444         key.type = BTRFS_EXTENT_DATA_KEY;
2445         key.offset = 0;
2446
2447         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2448         if (ret < 0) {
2449                 ret = 0;
2450                 goto out;
2451         }
2452         if (ret && path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
2453                 ret = btrfs_next_leaf(root, path);
2454                 if (ret) {
2455                         ret = 0;
2456                         goto out;
2457                 }
2458         }
2459         while (1) {
2460                 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2461                                       path->slots[0]);
2462                 if (found_key.objectid != ino ||
2463                     found_key.type != BTRFS_EXTENT_DATA_KEY)
2464                         break;
2465                 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
2466                                     struct btrfs_file_extent_item);
2467                 type = btrfs_file_extent_type(path->nodes[0], fi);
2468                 if (type != BTRFS_FILE_EXTENT_INLINE) {
2469                         ret = 1;
2470                         goto out;
2471                 }
2472         }
2473 out:
2474         btrfs_free_path(path);
2475         return ret;
2476 }
2477
2478 static u32 btrfs_type_to_imode(u8 type)
2479 {
2480         static u32 imode_by_btrfs_type[] = {
2481                 [BTRFS_FT_REG_FILE]     = S_IFREG,
2482                 [BTRFS_FT_DIR]          = S_IFDIR,
2483                 [BTRFS_FT_CHRDEV]       = S_IFCHR,
2484                 [BTRFS_FT_BLKDEV]       = S_IFBLK,
2485                 [BTRFS_FT_FIFO]         = S_IFIFO,
2486                 [BTRFS_FT_SOCK]         = S_IFSOCK,
2487                 [BTRFS_FT_SYMLINK]      = S_IFLNK,
2488         };
2489
2490         return imode_by_btrfs_type[(type)];
2491 }
2492
2493 static int repair_inode_no_item(struct btrfs_trans_handle *trans,
2494                                 struct btrfs_root *root,
2495                                 struct btrfs_path *path,
2496                                 struct inode_record *rec)
2497 {
2498         u8 filetype;
2499         u32 mode = 0700;
2500         int type_recovered = 0;
2501         int ret = 0;
2502
2503         printf("Trying to rebuild inode:%llu\n", rec->ino);
2504
2505         type_recovered = !find_file_type(rec, &filetype);
2506
2507         /*
2508          * Try to determine inode type if type not found.
2509          *
2510          * For found regular file extent, it must be FILE.
2511          * For found dir_item/index, it must be DIR.
2512          *
2513          * For undetermined one, use FILE as fallback.
2514          *
2515          * TODO:
2516          * 1. If found backref(inode_index/item is already handled) to it,
2517          *    it must be DIR.
2518          *    Need new inode-inode ref structure to allow search for that.
2519          */
2520         if (!type_recovered) {
2521                 if (rec->found_file_extent &&
2522                     find_normal_file_extent(root, rec->ino)) {
2523                         type_recovered = 1;
2524                         filetype = BTRFS_FT_REG_FILE;
2525                 } else if (rec->found_dir_item) {
2526                         type_recovered = 1;
2527                         filetype = BTRFS_FT_DIR;
2528                 } else if (!list_empty(&rec->orphan_extents)) {
2529                         type_recovered = 1;
2530                         filetype = BTRFS_FT_REG_FILE;
2531                 } else{
2532                         printf("Can't determint the filetype for inode %llu, assume it is a normal file\n",
2533                                rec->ino);
2534                         type_recovered = 1;
2535                         filetype = BTRFS_FT_REG_FILE;
2536                 }
2537         }
2538
2539         ret = btrfs_new_inode(trans, root, rec->ino,
2540                               mode | btrfs_type_to_imode(filetype));
2541         if (ret < 0)
2542                 goto out;
2543
2544         /*
2545          * Here inode rebuild is done, we only rebuild the inode item,
2546          * don't repair the nlink(like move to lost+found).
2547          * That is the job of nlink repair.
2548          *
2549          * We just fill the record and return
2550          */
2551         rec->found_dir_item = 1;
2552         rec->imode = mode | btrfs_type_to_imode(filetype);
2553         rec->nlink = 0;
2554         rec->errors &= ~I_ERR_NO_INODE_ITEM;
2555         /* Ensure the inode_nlinks repair function will be called */
2556         rec->errors |= I_ERR_LINK_COUNT_WRONG;
2557 out:
2558         return ret;
2559 }
2560
2561 static int repair_inode_orphan_extent(struct btrfs_trans_handle *trans,
2562                                       struct btrfs_root *root,
2563                                       struct btrfs_path *path,
2564                                       struct inode_record *rec)
2565 {
2566         struct orphan_data_extent *orphan;
2567         struct orphan_data_extent *tmp;
2568         int ret = 0;
2569
2570         list_for_each_entry_safe(orphan, tmp, &rec->orphan_extents, list) {
2571                 /*
2572                  * Check for conflicting file extents
2573                  *
2574                  * Here we don't know whether the extents is compressed or not,
2575                  * so we can only assume it not compressed nor data offset,
2576                  * and use its disk_len as extent length.
2577                  */
2578                 ret = btrfs_get_extent(NULL, root, path, orphan->objectid,
2579                                        orphan->offset, orphan->disk_len, 0);
2580                 btrfs_release_path(path);
2581                 if (ret < 0)
2582                         goto out;
2583                 if (!ret) {
2584                         fprintf(stderr,
2585                                 "orphan extent (%llu, %llu) conflicts, delete the orphan\n",
2586                                 orphan->disk_bytenr, orphan->disk_len);
2587                         ret = btrfs_free_extent(trans,
2588                                         root->fs_info->extent_root,
2589                                         orphan->disk_bytenr, orphan->disk_len,
2590                                         0, root->objectid, orphan->objectid,
2591                                         orphan->offset);
2592                         if (ret < 0)
2593                                 goto out;
2594                 }
2595                 ret = btrfs_insert_file_extent(trans, root, orphan->objectid,
2596                                 orphan->offset, orphan->disk_bytenr,
2597                                 orphan->disk_len, orphan->disk_len);
2598                 if (ret < 0)
2599                         goto out;
2600
2601                 /* Update file size info */
2602                 rec->found_size += orphan->disk_len;
2603                 if (rec->found_size == rec->nbytes)
2604                         rec->errors &= ~I_ERR_FILE_NBYTES_WRONG;
2605
2606                 /* Update the file extent hole info too */
2607                 ret = del_file_extent_hole(&rec->holes, orphan->offset,
2608                                            orphan->disk_len);
2609                 if (ret < 0)
2610                         goto out;
2611                 if (RB_EMPTY_ROOT(&rec->holes))
2612                         rec->errors &= ~I_ERR_FILE_EXTENT_DISCOUNT;
2613
2614                 list_del(&orphan->list);
2615                 free(orphan);
2616         }
2617         rec->errors &= ~I_ERR_FILE_EXTENT_ORPHAN;
2618 out:
2619         return ret;
2620 }
2621
2622 static int repair_inode_discount_extent(struct btrfs_trans_handle *trans,
2623                                         struct btrfs_root *root,
2624                                         struct btrfs_path *path,
2625                                         struct inode_record *rec)
2626 {
2627         struct rb_node *node;
2628         struct file_extent_hole *hole;
2629         int ret = 0;
2630
2631         node = rb_first(&rec->holes);
2632
2633         while (node) {
2634                 hole = rb_entry(node, struct file_extent_hole, node);
2635                 ret = btrfs_punch_hole(trans, root, rec->ino,
2636                                        hole->start, hole->len);
2637                 if (ret < 0)
2638                         goto out;
2639                 ret = del_file_extent_hole(&rec->holes, hole->start,
2640                                            hole->len);
2641                 if (ret < 0)
2642                         goto out;
2643                 if (RB_EMPTY_ROOT(&rec->holes))
2644                         rec->errors &= ~I_ERR_FILE_EXTENT_DISCOUNT;
2645                 node = rb_first(&rec->holes);
2646         }
2647         printf("Fixed discount file extents for inode: %llu in root: %llu\n",
2648                rec->ino, root->objectid);
2649 out:
2650         return ret;
2651 }
2652
2653 static int try_repair_inode(struct btrfs_root *root, struct inode_record *rec)
2654 {
2655         struct btrfs_trans_handle *trans;
2656         struct btrfs_path *path;
2657         int ret = 0;
2658
2659         if (!(rec->errors & (I_ERR_DIR_ISIZE_WRONG |
2660                              I_ERR_NO_ORPHAN_ITEM |
2661                              I_ERR_LINK_COUNT_WRONG |
2662                              I_ERR_NO_INODE_ITEM |
2663                              I_ERR_FILE_EXTENT_ORPHAN |
2664                              I_ERR_FILE_EXTENT_DISCOUNT)))
2665                 return rec->errors;
2666
2667         path = btrfs_alloc_path();
2668         if (!path)
2669                 return -ENOMEM;
2670
2671         /*
2672          * For nlink repair, it may create a dir and add link, so
2673          * 2 for parent(256)'s dir_index and dir_item
2674          * 2 for lost+found dir's inode_item and inode_ref
2675          * 1 for the new inode_ref of the file
2676          * 2 for lost+found dir's dir_index and dir_item for the file
2677          */
2678         trans = btrfs_start_transaction(root, 7);
2679         if (IS_ERR(trans)) {
2680                 btrfs_free_path(path);
2681                 return PTR_ERR(trans);
2682         }
2683
2684         if (rec->errors & I_ERR_NO_INODE_ITEM)
2685                 ret = repair_inode_no_item(trans, root, path, rec);
2686         if (!ret && rec->errors & I_ERR_FILE_EXTENT_ORPHAN)
2687                 ret = repair_inode_orphan_extent(trans, root, path, rec);
2688         if (!ret && rec->errors & I_ERR_FILE_EXTENT_DISCOUNT)
2689                 ret = repair_inode_discount_extent(trans, root, path, rec);
2690         if (!ret && rec->errors & I_ERR_DIR_ISIZE_WRONG)
2691                 ret = repair_inode_isize(trans, root, path, rec);
2692         if (!ret && rec->errors & I_ERR_NO_ORPHAN_ITEM)
2693                 ret = repair_inode_orphan_item(trans, root, path, rec);
2694         if (!ret && rec->errors & I_ERR_LINK_COUNT_WRONG)
2695                 ret = repair_inode_nlinks(trans, root, path, rec);
2696         btrfs_commit_transaction(trans, root);
2697         btrfs_free_path(path);
2698         return ret;
2699 }
2700
2701 static int check_inode_recs(struct btrfs_root *root,
2702                             struct cache_tree *inode_cache)
2703 {
2704         struct cache_extent *cache;
2705         struct ptr_node *node;
2706         struct inode_record *rec;
2707         struct inode_backref *backref;
2708         int stage = 0;
2709         int ret = 0;
2710         int err = 0;
2711         u64 error = 0;
2712         u64 root_dirid = btrfs_root_dirid(&root->root_item);
2713
2714         if (btrfs_root_refs(&root->root_item) == 0) {
2715                 if (!cache_tree_empty(inode_cache))
2716                         fprintf(stderr, "warning line %d\n", __LINE__);
2717                 return 0;
2718         }
2719
2720         /*
2721          * We need to record the highest inode number for later 'lost+found'
2722          * dir creation.
2723          * We must select a ino not used/refered by any existing inode, or
2724          * 'lost+found' ino may be a missing ino in a corrupted leaf,
2725          * this may cause 'lost+found' dir has wrong nlinks.
2726          */
2727         cache = last_cache_extent(inode_cache);
2728         if (cache) {
2729                 node = container_of(cache, struct ptr_node, cache);
2730                 rec = node->data;
2731                 if (rec->ino > root->highest_inode)
2732                         root->highest_inode = rec->ino;
2733         }
2734
2735         /*
2736          * We need to repair backrefs first because we could change some of the
2737          * errors in the inode recs.
2738          *
2739          * We also need to go through and delete invalid backrefs first and then
2740          * add the correct ones second.  We do this because we may get EEXIST
2741          * when adding back the correct index because we hadn't yet deleted the
2742          * invalid index.
2743          *
2744          * For example, if we were missing a dir index then the directories
2745          * isize would be wrong, so if we fixed the isize to what we thought it
2746          * would be and then fixed the backref we'd still have a invalid fs, so
2747          * we need to add back the dir index and then check to see if the isize
2748          * is still wrong.
2749          */
2750         while (stage < 3) {
2751                 stage++;
2752                 if (stage == 3 && !err)
2753                         break;
2754
2755                 cache = search_cache_extent(inode_cache, 0);
2756                 while (repair && cache) {
2757                         node = container_of(cache, struct ptr_node, cache);
2758                         rec = node->data;
2759                         cache = next_cache_extent(cache);
2760
2761                         /* Need to free everything up and rescan */
2762                         if (stage == 3) {
2763                                 remove_cache_extent(inode_cache, &node->cache);
2764                                 free(node);
2765                                 free_inode_rec(rec);
2766                                 continue;
2767                         }
2768
2769                         if (list_empty(&rec->backrefs))
2770                                 continue;
2771
2772                         ret = repair_inode_backrefs(root, rec, inode_cache,
2773                                                     stage == 1);
2774                         if (ret < 0) {
2775                                 err = ret;
2776                                 stage = 2;
2777                                 break;
2778                         } if (ret > 0) {
2779                                 err = -EAGAIN;
2780                         }
2781                 }
2782         }
2783         if (err)
2784                 return err;
2785
2786         rec = get_inode_rec(inode_cache, root_dirid, 0);
2787         if (rec) {
2788                 ret = check_root_dir(rec);
2789                 if (ret) {
2790                         fprintf(stderr, "root %llu root dir %llu error\n",
2791                                 (unsigned long long)root->root_key.objectid,
2792                                 (unsigned long long)root_dirid);
2793                         print_inode_error(root, rec);
2794                         error++;
2795                 }
2796         } else {
2797                 if (repair) {
2798                         struct btrfs_trans_handle *trans;
2799
2800                         trans = btrfs_start_transaction(root, 1);
2801                         if (IS_ERR(trans)) {
2802                                 err = PTR_ERR(trans);
2803                                 return err;
2804                         }
2805
2806                         fprintf(stderr,
2807                                 "root %llu missing its root dir, recreating\n",
2808                                 (unsigned long long)root->objectid);
2809
2810                         ret = btrfs_make_root_dir(trans, root, root_dirid);
2811                         BUG_ON(ret);
2812
2813                         btrfs_commit_transaction(trans, root);
2814                         return -EAGAIN;
2815                 }
2816
2817                 fprintf(stderr, "root %llu root dir %llu not found\n",
2818                         (unsigned long long)root->root_key.objectid,
2819                         (unsigned long long)root_dirid);
2820         }
2821
2822         while (1) {
2823                 cache = search_cache_extent(inode_cache, 0);
2824                 if (!cache)
2825                         break;
2826                 node = container_of(cache, struct ptr_node, cache);
2827                 rec = node->data;
2828                 remove_cache_extent(inode_cache, &node->cache);
2829                 free(node);
2830                 if (rec->ino == root_dirid ||
2831                     rec->ino == BTRFS_ORPHAN_OBJECTID) {
2832                         free_inode_rec(rec);
2833                         continue;
2834                 }
2835
2836                 if (rec->errors & I_ERR_NO_ORPHAN_ITEM) {
2837                         ret = check_orphan_item(root, rec->ino);
2838                         if (ret == 0)
2839                                 rec->errors &= ~I_ERR_NO_ORPHAN_ITEM;
2840                         if (can_free_inode_rec(rec)) {
2841                                 free_inode_rec(rec);
2842                                 continue;
2843                         }
2844                 }
2845
2846                 if (!rec->found_inode_item)
2847                         rec->errors |= I_ERR_NO_INODE_ITEM;
2848                 if (rec->found_link != rec->nlink)
2849                         rec->errors |= I_ERR_LINK_COUNT_WRONG;
2850                 if (repair) {
2851                         ret = try_repair_inode(root, rec);
2852                         if (ret == 0 && can_free_inode_rec(rec)) {
2853                                 free_inode_rec(rec);
2854                                 continue;
2855                         }
2856                         ret = 0;
2857                 }
2858
2859                 if (!(repair && ret == 0))
2860                         error++;
2861                 print_inode_error(root, rec);
2862                 list_for_each_entry(backref, &rec->backrefs, list) {
2863                         if (!backref->found_dir_item)
2864                                 backref->errors |= REF_ERR_NO_DIR_ITEM;
2865                         if (!backref->found_dir_index)
2866                                 backref->errors |= REF_ERR_NO_DIR_INDEX;
2867                         if (!backref->found_inode_ref)
2868                                 backref->errors |= REF_ERR_NO_INODE_REF;
2869                         fprintf(stderr, "\tunresolved ref dir %llu index %llu"
2870                                 " namelen %u name %s filetype %d errors %x",
2871                                 (unsigned long long)backref->dir,
2872                                 (unsigned long long)backref->index,
2873                                 backref->namelen, backref->name,
2874                                 backref->filetype, backref->errors);
2875                         print_ref_error(backref->errors);
2876                 }
2877                 free_inode_rec(rec);
2878         }
2879         return (error > 0) ? -1 : 0;
2880 }
2881
2882 static struct root_record *get_root_rec(struct cache_tree *root_cache,
2883                                         u64 objectid)
2884 {
2885         struct cache_extent *cache;
2886         struct root_record *rec = NULL;
2887         int ret;
2888
2889         cache = lookup_cache_extent(root_cache, objectid, 1);
2890         if (cache) {
2891                 rec = container_of(cache, struct root_record, cache);
2892         } else {
2893                 rec = calloc(1, sizeof(*rec));
2894                 rec->objectid = objectid;
2895                 INIT_LIST_HEAD(&rec->backrefs);
2896                 rec->cache.start = objectid;
2897                 rec->cache.size = 1;
2898
2899                 ret = insert_cache_extent(root_cache, &rec->cache);
2900                 BUG_ON(ret);
2901         }
2902         return rec;
2903 }
2904
2905 static struct root_backref *get_root_backref(struct root_record *rec,
2906                                              u64 ref_root, u64 dir, u64 index,
2907                                              const char *name, int namelen)
2908 {
2909         struct root_backref *backref;
2910
2911         list_for_each_entry(backref, &rec->backrefs, list) {
2912                 if (backref->ref_root != ref_root || backref->dir != dir ||
2913                     backref->namelen != namelen)
2914                         continue;
2915                 if (memcmp(name, backref->name, namelen))
2916                         continue;
2917                 return backref;
2918         }
2919
2920         backref = malloc(sizeof(*backref) + namelen + 1);
2921         memset(backref, 0, sizeof(*backref));
2922         backref->ref_root = ref_root;
2923         backref->dir = dir;
2924         backref->index = index;
2925         backref->namelen = namelen;
2926         memcpy(backref->name, name, namelen);
2927         backref->name[namelen] = '\0';
2928         list_add_tail(&backref->list, &rec->backrefs);
2929         return backref;
2930 }
2931
2932 static void free_root_record(struct cache_extent *cache)
2933 {
2934         struct root_record *rec;
2935         struct root_backref *backref;
2936
2937         rec = container_of(cache, struct root_record, cache);
2938         while (!list_empty(&rec->backrefs)) {
2939                 backref = list_entry(rec->backrefs.next,
2940                                      struct root_backref, list);
2941                 list_del(&backref->list);
2942                 free(backref);
2943         }
2944
2945         kfree(rec);
2946 }
2947
2948 FREE_EXTENT_CACHE_BASED_TREE(root_recs, free_root_record);
2949
2950 static int add_root_backref(struct cache_tree *root_cache,
2951                             u64 root_id, u64 ref_root, u64 dir, u64 index,
2952                             const char *name, int namelen,
2953                             int item_type, int errors)
2954 {
2955         struct root_record *rec;
2956         struct root_backref *backref;
2957
2958         rec = get_root_rec(root_cache, root_id);
2959         backref = get_root_backref(rec, ref_root, dir, index, name, namelen);
2960
2961         backref->errors |= errors;
2962
2963         if (item_type != BTRFS_DIR_ITEM_KEY) {
2964                 if (backref->found_dir_index || backref->found_back_ref ||
2965                     backref->found_forward_ref) {
2966                         if (backref->index != index)
2967                                 backref->errors |= REF_ERR_INDEX_UNMATCH;
2968                 } else {
2969                         backref->index = index;
2970                 }
2971         }
2972
2973         if (item_type == BTRFS_DIR_ITEM_KEY) {
2974                 if (backref->found_forward_ref)
2975                         rec->found_ref++;
2976                 backref->found_dir_item = 1;
2977         } else if (item_type == BTRFS_DIR_INDEX_KEY) {
2978                 backref->found_dir_index = 1;
2979         } else if (item_type == BTRFS_ROOT_REF_KEY) {
2980                 if (backref->found_forward_ref)
2981                         backref->errors |= REF_ERR_DUP_ROOT_REF;
2982                 else if (backref->found_dir_item)
2983                         rec->found_ref++;
2984                 backref->found_forward_ref = 1;
2985         } else if (item_type == BTRFS_ROOT_BACKREF_KEY) {
2986                 if (backref->found_back_ref)
2987                         backref->errors |= REF_ERR_DUP_ROOT_BACKREF;
2988                 backref->found_back_ref = 1;
2989         } else {
2990                 BUG_ON(1);
2991         }
2992
2993         if (backref->found_forward_ref && backref->found_dir_item)
2994                 backref->reachable = 1;
2995         return 0;
2996 }
2997
2998 static int merge_root_recs(struct btrfs_root *root,
2999                            struct cache_tree *src_cache,
3000                            struct cache_tree *dst_cache)
3001 {
3002         struct cache_extent *cache;
3003         struct ptr_node *node;
3004         struct inode_record *rec;
3005         struct inode_backref *backref;
3006         int ret = 0;
3007
3008         if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
3009                 free_inode_recs_tree(src_cache);
3010                 return 0;
3011         }
3012
3013         while (1) {
3014                 cache = search_cache_extent(src_cache, 0);
3015                 if (!cache)
3016                         break;
3017                 node = container_of(cache, struct ptr_node, cache);
3018                 rec = node->data;
3019                 remove_cache_extent(src_cache, &node->cache);
3020                 free(node);
3021
3022                 ret = is_child_root(root, root->objectid, rec->ino);
3023                 if (ret < 0)
3024                         break;
3025                 else if (ret == 0)
3026                         goto skip;
3027
3028                 list_for_each_entry(backref, &rec->backrefs, list) {
3029                         BUG_ON(backref->found_inode_ref);
3030                         if (backref->found_dir_item)
3031                                 add_root_backref(dst_cache, rec->ino,
3032                                         root->root_key.objectid, backref->dir,
3033                                         backref->index, backref->name,
3034                                         backref->namelen, BTRFS_DIR_ITEM_KEY,
3035                                         backref->errors);
3036                         if (backref->found_dir_index)
3037                                 add_root_backref(dst_cache, rec->ino,
3038                                         root->root_key.objectid, backref->dir,
3039                                         backref->index, backref->name,
3040                                         backref->namelen, BTRFS_DIR_INDEX_KEY,
3041                                         backref->errors);
3042                 }
3043 skip:
3044                 free_inode_rec(rec);
3045         }
3046         if (ret < 0)
3047                 return ret;
3048         return 0;
3049 }
3050
3051 static int check_root_refs(struct btrfs_root *root,
3052                            struct cache_tree *root_cache)
3053 {
3054         struct root_record *rec;
3055         struct root_record *ref_root;
3056         struct root_backref *backref;
3057         struct cache_extent *cache;
3058         int loop = 1;
3059         int ret;
3060         int error;
3061         int errors = 0;
3062
3063         rec = get_root_rec(root_cache, BTRFS_FS_TREE_OBJECTID);
3064         rec->found_ref = 1;
3065
3066         /* fixme: this can not detect circular references */
3067         while (loop) {
3068                 loop = 0;
3069                 cache = search_cache_extent(root_cache, 0);
3070                 while (1) {
3071                         if (!cache)
3072                                 break;
3073                         rec = container_of(cache, struct root_record, cache);
3074                         cache = next_cache_extent(cache);
3075
3076                         if (rec->found_ref == 0)
3077                                 continue;
3078
3079                         list_for_each_entry(backref, &rec->backrefs, list) {
3080                                 if (!backref->reachable)
3081                                         continue;
3082
3083                                 ref_root = get_root_rec(root_cache,
3084                                                         backref->ref_root);
3085                                 if (ref_root->found_ref > 0)
3086                                         continue;
3087
3088                                 backref->reachable = 0;
3089                                 rec->found_ref--;
3090                                 if (rec->found_ref == 0)
3091                                         loop = 1;
3092                         }
3093                 }
3094         }
3095
3096         cache = search_cache_extent(root_cache, 0);
3097         while (1) {
3098                 if (!cache)
3099                         break;
3100                 rec = container_of(cache, struct root_record, cache);
3101                 cache = next_cache_extent(cache);
3102
3103                 if (rec->found_ref == 0 &&
3104                     rec->objectid >= BTRFS_FIRST_FREE_OBJECTID &&
3105                     rec->objectid <= BTRFS_LAST_FREE_OBJECTID) {
3106                         ret = check_orphan_item(root->fs_info->tree_root,
3107                                                 rec->objectid);
3108                         if (ret == 0)
3109                                 continue;
3110
3111                         /*
3112                          * If we don't have a root item then we likely just have
3113                          * a dir item in a snapshot for this root but no actual
3114                          * ref key or anything so it's meaningless.
3115                          */
3116                         if (!rec->found_root_item)
3117                                 continue;
3118                         errors++;
3119                         fprintf(stderr, "fs tree %llu not referenced\n",
3120                                 (unsigned long long)rec->objectid);
3121                 }
3122
3123                 error = 0;
3124                 if (rec->found_ref > 0 && !rec->found_root_item)
3125                         error = 1;
3126                 list_for_each_entry(backref, &rec->backrefs, list) {
3127                         if (!backref->found_dir_item)
3128                                 backref->errors |= REF_ERR_NO_DIR_ITEM;
3129                         if (!backref->found_dir_index)
3130                                 backref->errors |= REF_ERR_NO_DIR_INDEX;
3131                         if (!backref->found_back_ref)
3132                                 backref->errors |= REF_ERR_NO_ROOT_BACKREF;
3133                         if (!backref->found_forward_ref)
3134                                 backref->errors |= REF_ERR_NO_ROOT_REF;
3135                         if (backref->reachable && backref->errors)
3136                                 error = 1;
3137                 }
3138                 if (!error)
3139                         continue;
3140
3141                 errors++;
3142                 fprintf(stderr, "fs tree %llu refs %u %s\n",
3143                         (unsigned long long)rec->objectid, rec->found_ref,
3144                          rec->found_root_item ? "" : "not found");
3145
3146                 list_for_each_entry(backref, &rec->backrefs, list) {
3147                         if (!backref->reachable)
3148                                 continue;
3149                         if (!backref->errors && rec->found_root_item)
3150                                 continue;
3151                         fprintf(stderr, "\tunresolved ref root %llu dir %llu"
3152                                 " index %llu namelen %u name %s errors %x\n",
3153                                 (unsigned long long)backref->ref_root,
3154                                 (unsigned long long)backref->dir,
3155                                 (unsigned long long)backref->index,
3156                                 backref->namelen, backref->name,
3157                                 backref->errors);
3158                         print_ref_error(backref->errors);
3159                 }
3160         }
3161         return errors > 0 ? 1 : 0;
3162 }
3163
3164 static int process_root_ref(struct extent_buffer *eb, int slot,
3165                             struct btrfs_key *key,
3166                             struct cache_tree *root_cache)
3167 {
3168         u64 dirid;
3169         u64 index;
3170         u32 len;
3171         u32 name_len;
3172         struct btrfs_root_ref *ref;
3173         char namebuf[BTRFS_NAME_LEN];
3174         int error;
3175
3176         ref = btrfs_item_ptr(eb, slot, struct btrfs_root_ref);
3177
3178         dirid = btrfs_root_ref_dirid(eb, ref);
3179         index = btrfs_root_ref_sequence(eb, ref);
3180         name_len = btrfs_root_ref_name_len(eb, ref);
3181
3182         if (name_len <= BTRFS_NAME_LEN) {
3183                 len = name_len;
3184                 error = 0;
3185         } else {
3186                 len = BTRFS_NAME_LEN;
3187                 error = REF_ERR_NAME_TOO_LONG;
3188         }
3189         read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
3190
3191         if (key->type == BTRFS_ROOT_REF_KEY) {
3192                 add_root_backref(root_cache, key->offset, key->objectid, dirid,
3193                                  index, namebuf, len, key->type, error);
3194         } else {
3195                 add_root_backref(root_cache, key->objectid, key->offset, dirid,
3196                                  index, namebuf, len, key->type, error);
3197         }
3198         return 0;
3199 }
3200
3201 static void free_corrupt_block(struct cache_extent *cache)
3202 {
3203         struct btrfs_corrupt_block *corrupt;
3204
3205         corrupt = container_of(cache, struct btrfs_corrupt_block, cache);
3206         free(corrupt);
3207 }
3208
3209 FREE_EXTENT_CACHE_BASED_TREE(corrupt_blocks, free_corrupt_block);
3210
3211 /*
3212  * Repair the btree of the given root.
3213  *
3214  * The fix is to remove the node key in corrupt_blocks cache_tree.
3215  * and rebalance the tree.
3216  * After the fix, the btree should be writeable.
3217  */
3218 static int repair_btree(struct btrfs_root *root,
3219                         struct cache_tree *corrupt_blocks)
3220 {
3221         struct btrfs_trans_handle *trans;
3222         struct btrfs_path *path;
3223         struct btrfs_corrupt_block *corrupt;
3224         struct cache_extent *cache;
3225         struct btrfs_key key;
3226         u64 offset;
3227         int level;
3228         int ret = 0;
3229
3230         if (cache_tree_empty(corrupt_blocks))
3231                 return 0;
3232
3233         path = btrfs_alloc_path();
3234         if (!path)
3235                 return -ENOMEM;
3236
3237         trans = btrfs_start_transaction(root, 1);
3238         if (IS_ERR(trans)) {
3239                 ret = PTR_ERR(trans);
3240                 fprintf(stderr, "Error starting transaction: %s\n",
3241                         strerror(-ret));
3242                 goto out_free_path;
3243         }
3244         cache = first_cache_extent(corrupt_blocks);
3245         while (cache) {
3246                 corrupt = container_of(cache, struct btrfs_corrupt_block,
3247                                        cache);
3248                 level = corrupt->level;
3249                 path->lowest_level = level;
3250                 key.objectid = corrupt->key.objectid;
3251                 key.type = corrupt->key.type;
3252                 key.offset = corrupt->key.offset;
3253
3254                 /*
3255                  * Here we don't want to do any tree balance, since it may
3256                  * cause a balance with corrupted brother leaf/node,
3257                  * so ins_len set to 0 here.
3258                  * Balance will be done after all corrupt node/leaf is deleted.
3259                  */
3260                 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
3261                 if (ret < 0)
3262                         goto out;
3263                 offset = btrfs_node_blockptr(path->nodes[level],
3264                                              path->slots[level]);
3265
3266                 /* Remove the ptr */
3267                 ret = btrfs_del_ptr(trans, root, path, level,
3268                                     path->slots[level]);
3269                 if (ret < 0)
3270                         goto out;
3271                 /*
3272                  * Remove the corresponding extent
3273                  * return value is not concerned.
3274                  */
3275                 btrfs_release_path(path);
3276                 ret = btrfs_free_extent(trans, root, offset, root->nodesize,
3277                                         0, root->root_key.objectid,
3278                                         level - 1, 0);
3279                 cache = next_cache_extent(cache);
3280         }
3281
3282         /* Balance the btree using btrfs_search_slot() */
3283         cache = first_cache_extent(corrupt_blocks);
3284         while (cache) {
3285                 corrupt = container_of(cache, struct btrfs_corrupt_block,
3286                                        cache);
3287                 memcpy(&key, &corrupt->key, sizeof(key));
3288                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3289                 if (ret < 0)
3290                         goto out;
3291                 /* return will always >0 since it won't find the item */
3292                 ret = 0;
3293                 btrfs_release_path(path);
3294                 cache = next_cache_extent(cache);
3295         }
3296 out:
3297         btrfs_commit_transaction(trans, root);
3298 out_free_path:
3299         btrfs_free_path(path);
3300         return ret;
3301 }
3302
3303 static int check_fs_root(struct btrfs_root *root,
3304                          struct cache_tree *root_cache,
3305                          struct walk_control *wc)
3306 {
3307         int ret = 0;
3308         int err = 0;
3309         int wret;
3310         int level;
3311         struct btrfs_path path;
3312         struct shared_node root_node;
3313         struct root_record *rec;
3314         struct btrfs_root_item *root_item = &root->root_item;
3315         struct cache_tree corrupt_blocks;
3316         struct orphan_data_extent *orphan;
3317         struct orphan_data_extent *tmp;
3318         enum btrfs_tree_block_status status;
3319
3320         /*
3321          * Reuse the corrupt_block cache tree to record corrupted tree block
3322          *
3323          * Unlike the usage in extent tree check, here we do it in a per
3324          * fs/subvol tree base.
3325          */
3326         cache_tree_init(&corrupt_blocks);
3327         root->fs_info->corrupt_blocks = &corrupt_blocks;
3328
3329         if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
3330                 rec = get_root_rec(root_cache, root->root_key.objectid);
3331                 if (btrfs_root_refs(root_item) > 0)
3332                         rec->found_root_item = 1;
3333         }
3334
3335         btrfs_init_path(&path);
3336         memset(&root_node, 0, sizeof(root_node));
3337         cache_tree_init(&root_node.root_cache);
3338         cache_tree_init(&root_node.inode_cache);
3339
3340         /* Move the orphan extent record to corresponding inode_record */
3341         list_for_each_entry_safe(orphan, tmp,
3342                                  &root->orphan_data_extents, list) {
3343                 struct inode_record *inode;
3344
3345                 inode = get_inode_rec(&root_node.inode_cache, orphan->objectid,
3346                                       1);
3347                 inode->errors |= I_ERR_FILE_EXTENT_ORPHAN;
3348                 list_move(&orphan->list, &inode->orphan_extents);
3349         }
3350
3351         level = btrfs_header_level(root->node);
3352         memset(wc->nodes, 0, sizeof(wc->nodes));
3353         wc->nodes[level] = &root_node;
3354         wc->active_node = level;
3355         wc->root_level = level;
3356
3357         /* We may not have checked the root block, lets do that now */
3358         if (btrfs_is_leaf(root->node))
3359                 status = btrfs_check_leaf(root, NULL, root->node);
3360         else
3361                 status = btrfs_check_node(root, NULL, root->node);
3362         if (status != BTRFS_TREE_BLOCK_CLEAN)
3363                 return -EIO;
3364
3365         if (btrfs_root_refs(root_item) > 0 ||
3366             btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
3367                 path.nodes[level] = root->node;
3368                 extent_buffer_get(root->node);
3369                 path.slots[level] = 0;
3370         } else {
3371                 struct btrfs_key key;
3372                 struct btrfs_disk_key found_key;
3373
3374                 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
3375                 level = root_item->drop_level;
3376                 path.lowest_level = level;
3377                 wret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
3378                 if (wret < 0)
3379                         goto skip_walking;
3380                 btrfs_node_key(path.nodes[level], &found_key,
3381                                 path.slots[level]);
3382                 WARN_ON(memcmp(&found_key, &root_item->drop_progress,
3383                                         sizeof(found_key)));
3384         }
3385
3386         while (1) {
3387                 wret = walk_down_tree(root, &path, wc, &level);
3388                 if (wret < 0)
3389                         ret = wret;
3390                 if (wret != 0)
3391                         break;
3392
3393                 wret = walk_up_tree(root, &path, wc, &level);
3394                 if (wret < 0)
3395                         ret = wret;
3396                 if (wret != 0)
3397                         break;
3398         }
3399 skip_walking:
3400         btrfs_release_path(&path);
3401
3402         if (!cache_tree_empty(&corrupt_blocks)) {
3403                 struct cache_extent *cache;
3404                 struct btrfs_corrupt_block *corrupt;
3405
3406                 printf("The following tree block(s) is corrupted in tree %llu:\n",
3407                        root->root_key.objectid);
3408                 cache = first_cache_extent(&corrupt_blocks);
3409                 while (cache) {
3410                         corrupt = container_of(cache,
3411                                                struct btrfs_corrupt_block,
3412                                                cache);
3413                         printf("\ttree block bytenr: %llu, level: %d, node key: (%llu, %u, %llu)\n",
3414                                cache->start, corrupt->level,
3415                                corrupt->key.objectid, corrupt->key.type,
3416                                corrupt->key.offset);
3417                         cache = next_cache_extent(cache);
3418                 }
3419                 if (repair) {
3420                         printf("Try to repair the btree for root %llu\n",
3421                                root->root_key.objectid);
3422                         ret = repair_btree(root, &corrupt_blocks);
3423                         if (ret < 0)
3424                                 fprintf(stderr, "Failed to repair btree: %s\n",
3425                                         strerror(-ret));
3426                         if (!ret)
3427                                 printf("Btree for root %llu is fixed\n",
3428                                        root->root_key.objectid);
3429                 }
3430         }
3431
3432         err = merge_root_recs(root, &root_node.root_cache, root_cache);
3433         if (err < 0)
3434                 ret = err;
3435
3436         if (root_node.current) {
3437                 root_node.current->checked = 1;
3438                 maybe_free_inode_rec(&root_node.inode_cache,
3439                                 root_node.current);
3440         }
3441
3442         err = check_inode_recs(root, &root_node.inode_cache);
3443         if (!ret)
3444                 ret = err;
3445
3446         free_corrupt_blocks_tree(&corrupt_blocks);
3447         root->fs_info->corrupt_blocks = NULL;
3448         free_orphan_data_extents(&root->orphan_data_extents);
3449         return ret;
3450 }
3451
3452 static int fs_root_objectid(u64 objectid)
3453 {
3454         if (objectid == BTRFS_TREE_RELOC_OBJECTID ||
3455             objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
3456                 return 1;
3457         return is_fstree(objectid);
3458 }
3459
3460 static int check_fs_roots(struct btrfs_root *root,
3461                           struct cache_tree *root_cache)
3462 {
3463         struct btrfs_path path;
3464         struct btrfs_key key;
3465         struct walk_control wc;
3466         struct extent_buffer *leaf, *tree_node;
3467         struct btrfs_root *tmp_root;
3468         struct btrfs_root *tree_root = root->fs_info->tree_root;
3469         int ret;
3470         int err = 0;
3471
3472         /*
3473          * Just in case we made any changes to the extent tree that weren't
3474          * reflected into the free space cache yet.
3475          */
3476         if (repair)
3477                 reset_cached_block_groups(root->fs_info);
3478         memset(&wc, 0, sizeof(wc));
3479         cache_tree_init(&wc.shared);
3480         btrfs_init_path(&path);
3481
3482 again:
3483         key.offset = 0;
3484         key.objectid = 0;
3485         key.type = BTRFS_ROOT_ITEM_KEY;
3486         ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
3487         if (ret < 0) {
3488                 err = 1;
3489                 goto out;
3490         }
3491         tree_node = tree_root->node;
3492         while (1) {
3493                 if (tree_node != tree_root->node) {
3494                         free_root_recs_tree(root_cache);
3495                         btrfs_release_path(&path);
3496                         goto again;
3497                 }
3498                 leaf = path.nodes[0];
3499                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
3500                         ret = btrfs_next_leaf(tree_root, &path);
3501                         if (ret) {
3502                                 if (ret < 0)
3503                                         err = 1;
3504                                 break;
3505                         }
3506                         leaf = path.nodes[0];
3507                 }
3508                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
3509                 if (key.type == BTRFS_ROOT_ITEM_KEY &&
3510                     fs_root_objectid(key.objectid)) {
3511                         if (key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
3512                                 tmp_root = btrfs_read_fs_root_no_cache(
3513                                                 root->fs_info, &key);
3514                         } else {
3515                                 key.offset = (u64)-1;
3516                                 tmp_root = btrfs_read_fs_root(
3517                                                 root->fs_info, &key);
3518                         }
3519                         if (IS_ERR(tmp_root)) {
3520                                 err = 1;
3521                                 goto next;
3522                         }
3523                         ret = check_fs_root(tmp_root, root_cache, &wc);
3524                         if (ret == -EAGAIN) {
3525                                 free_root_recs_tree(root_cache);
3526                                 btrfs_release_path(&path);
3527                                 goto again;
3528                         }
3529                         if (ret)
3530                                 err = 1;
3531                         if (key.objectid == BTRFS_TREE_RELOC_OBJECTID)
3532                                 btrfs_free_fs_root(tmp_root);
3533                 } else if (key.type == BTRFS_ROOT_REF_KEY ||
3534                            key.type == BTRFS_ROOT_BACKREF_KEY) {
3535                         process_root_ref(leaf, path.slots[0], &key,
3536                                          root_cache);
3537                 }
3538 next:
3539                 path.slots[0]++;
3540         }
3541 out:
3542         btrfs_release_path(&path);
3543         if (err)
3544                 free_extent_cache_tree(&wc.shared);
3545         if (!cache_tree_empty(&wc.shared))
3546                 fprintf(stderr, "warning line %d\n", __LINE__);
3547
3548         return err;
3549 }
3550
3551 static int all_backpointers_checked(struct extent_record *rec, int print_errs)
3552 {
3553         struct list_head *cur = rec->backrefs.next;
3554         struct extent_backref *back;
3555         struct tree_backref *tback;
3556         struct data_backref *dback;
3557         u64 found = 0;
3558         int err = 0;
3559
3560         while(cur != &rec->backrefs) {
3561                 back = list_entry(cur, struct extent_backref, list);
3562                 cur = cur->next;
3563                 if (!back->found_extent_tree) {
3564                         err = 1;
3565                         if (!print_errs)
3566                                 goto out;
3567                         if (back->is_data) {
3568                                 dback = (struct data_backref *)back;
3569                                 fprintf(stderr, "Backref %llu %s %llu"
3570                                         " owner %llu offset %llu num_refs %lu"
3571                                         " not found in extent tree\n",
3572                                         (unsigned long long)rec->start,
3573                                         back->full_backref ?
3574                                         "parent" : "root",
3575                                         back->full_backref ?
3576                                         (unsigned long long)dback->parent:
3577                                         (unsigned long long)dback->root,
3578                                         (unsigned long long)dback->owner,
3579                                         (unsigned long long)dback->offset,
3580                                         (unsigned long)dback->num_refs);
3581                         } else {
3582                                 tback = (struct tree_backref *)back;
3583                                 fprintf(stderr, "Backref %llu parent %llu"
3584                                         " root %llu not found in extent tree\n",
3585                                         (unsigned long long)rec->start,
3586                                         (unsigned long long)tback->parent,
3587                                         (unsigned long long)tback->root);
3588                         }
3589                 }
3590                 if (!back->is_data && !back->found_ref) {
3591                         err = 1;
3592                         if (!print_errs)
3593                                 goto out;
3594                         tback = (struct tree_backref *)back;
3595                         fprintf(stderr, "Backref %llu %s %llu not referenced back %p\n",
3596                                 (unsigned long long)rec->start,
3597                                 back->full_backref ? "parent" : "root",
3598                                 back->full_backref ?
3599                                 (unsigned long long)tback->parent :
3600                                 (unsigned long long)tback->root, back);
3601                 }
3602                 if (back->is_data) {
3603                         dback = (struct data_backref *)back;
3604                         if (dback->found_ref != dback->num_refs) {
3605                                 err = 1;
3606                                 if (!print_errs)
3607                                         goto out;
3608                                 fprintf(stderr, "Incorrect local backref count"
3609                                         " on %llu %s %llu owner %llu"
3610                                         " offset %llu found %u wanted %u back %p\n",
3611                                         (unsigned long long)rec->start,
3612                                         back->full_backref ?
3613                                         "parent" : "root",
3614                                         back->full_backref ?
3615                                         (unsigned long long)dback->parent:
3616                                         (unsigned long long)dback->root,
3617                                         (unsigned long long)dback->owner,
3618                                         (unsigned long long)dback->offset,
3619                                         dback->found_ref, dback->num_refs, back);
3620                         }
3621                         if (dback->disk_bytenr != rec->start) {
3622                                 err = 1;
3623                                 if (!print_errs)
3624                                         goto out;
3625                                 fprintf(stderr, "Backref disk bytenr does not"
3626                                         " match extent record, bytenr=%llu, "
3627                                         "ref bytenr=%llu\n",
3628                                         (unsigned long long)rec->start,
3629                                         (unsigned long long)dback->disk_bytenr);
3630                         }
3631
3632                         if (dback->bytes != rec->nr) {
3633                                 err = 1;
3634                                 if (!print_errs)
3635                                         goto out;
3636                                 fprintf(stderr, "Backref bytes do not match "
3637                                         "extent backref, bytenr=%llu, ref "
3638                                         "bytes=%llu, backref bytes=%llu\n",
3639                                         (unsigned long long)rec->start,
3640                                         (unsigned long long)rec->nr,
3641                                         (unsigned long long)dback->bytes);
3642                         }
3643                 }
3644                 if (!back->is_data) {
3645                         found += 1;
3646                 } else {
3647                         dback = (struct data_backref *)back;
3648                         found += dback->found_ref;
3649                 }
3650         }
3651         if (found != rec->refs) {
3652                 err = 1;
3653                 if (!print_errs)
3654                         goto out;
3655                 fprintf(stderr, "Incorrect global backref count "
3656                         "on %llu found %llu wanted %llu\n",
3657                         (unsigned long long)rec->start,
3658                         (unsigned long long)found,
3659                         (unsigned long long)rec->refs);
3660         }
3661 out:
3662         return err;
3663 }
3664
3665 static int free_all_extent_backrefs(struct extent_record *rec)
3666 {
3667         struct extent_backref *back;
3668         struct list_head *cur;
3669         while (!list_empty(&rec->backrefs)) {
3670                 cur = rec->backrefs.next;
3671                 back = list_entry(cur, struct extent_backref, list);
3672                 list_del(cur);
3673                 free(back);
3674         }
3675         return 0;
3676 }
3677
3678 static void free_extent_record_cache(struct btrfs_fs_info *fs_info,
3679                                      struct cache_tree *extent_cache)
3680 {
3681         struct cache_extent *cache;
3682         struct extent_record *rec;
3683
3684         while (1) {
3685                 cache = first_cache_extent(extent_cache);
3686                 if (!cache)
3687                         break;
3688                 rec = container_of(cache, struct extent_record, cache);
3689                 remove_cache_extent(extent_cache, cache);
3690                 free_all_extent_backrefs(rec);
3691                 free(rec);
3692         }
3693 }
3694
3695 static int maybe_free_extent_rec(struct cache_tree *extent_cache,
3696                                  struct extent_record *rec)
3697 {
3698         if (rec->content_checked && rec->owner_ref_checked &&
3699             rec->extent_item_refs == rec->refs && rec->refs > 0 &&
3700             rec->num_duplicates == 0 && !all_backpointers_checked(rec, 0) &&
3701             !rec->bad_full_backref) {
3702                 remove_cache_extent(extent_cache, &rec->cache);
3703                 free_all_extent_backrefs(rec);
3704                 list_del_init(&rec->list);
3705                 free(rec);
3706         }
3707         return 0;
3708 }
3709
3710 static int check_owner_ref(struct btrfs_root *root,
3711                             struct extent_record *rec,
3712                             struct extent_buffer *buf)
3713 {
3714         struct extent_backref *node;
3715         struct tree_backref *back;
3716         struct btrfs_root *ref_root;
3717         struct btrfs_key key;
3718         struct btrfs_path path;
3719         struct extent_buffer *parent;
3720         int level;
3721         int found = 0;
3722         int ret;
3723
3724         list_for_each_entry(node, &rec->backrefs, list) {
3725                 if (node->is_data)
3726                         continue;
3727                 if (!node->found_ref)
3728                         continue;
3729                 if (node->full_backref)
3730                         continue;
3731                 back = (struct tree_backref *)node;
3732                 if (btrfs_header_owner(buf) == back->root)
3733                         return 0;
3734         }
3735         BUG_ON(rec->is_root);
3736
3737         /* try to find the block by search corresponding fs tree */
3738         key.objectid = btrfs_header_owner(buf);
3739         key.type = BTRFS_ROOT_ITEM_KEY;
3740         key.offset = (u64)-1;
3741
3742         ref_root = btrfs_read_fs_root(root->fs_info, &key);
3743         if (IS_ERR(ref_root))
3744                 return 1;
3745
3746         level = btrfs_header_level(buf);
3747         if (level == 0)
3748                 btrfs_item_key_to_cpu(buf, &key, 0);
3749         else
3750                 btrfs_node_key_to_cpu(buf, &key, 0);
3751
3752         btrfs_init_path(&path);
3753         path.lowest_level = level + 1;
3754         ret = btrfs_search_slot(NULL, ref_root, &key, &path, 0, 0);
3755         if (ret < 0)
3756                 return 0;
3757
3758         parent = path.nodes[level + 1];
3759         if (parent && buf->start == btrfs_node_blockptr(parent,
3760                                                         path.slots[level + 1]))
3761                 found = 1;
3762
3763         btrfs_release_path(&path);
3764         return found ? 0 : 1;
3765 }
3766
3767 static int is_extent_tree_record(struct extent_record *rec)
3768 {
3769         struct list_head *cur = rec->backrefs.next;
3770         struct extent_backref *node;
3771         struct tree_backref *back;
3772         int is_extent = 0;
3773
3774         while(cur != &rec->backrefs) {
3775                 node = list_entry(cur, struct extent_backref, list);
3776                 cur = cur->next;
3777                 if (node->is_data)
3778                         return 0;
3779                 back = (struct tree_backref *)node;
3780                 if (node->full_backref)
3781                         return 0;
3782                 if (back->root == BTRFS_EXTENT_TREE_OBJECTID)
3783                         is_extent = 1;
3784         }
3785         return is_extent;
3786 }
3787
3788
3789 static int record_bad_block_io(struct btrfs_fs_info *info,
3790                                struct cache_tree *extent_cache,
3791                                u64 start, u64 len)
3792 {
3793         struct extent_record *rec;
3794         struct cache_extent *cache;
3795         struct btrfs_key key;
3796
3797         cache = lookup_cache_extent(extent_cache, start, len);
3798         if (!cache)
3799                 return 0;
3800
3801         rec = container_of(cache, struct extent_record, cache);
3802         if (!is_extent_tree_record(rec))
3803                 return 0;
3804
3805         btrfs_disk_key_to_cpu(&key, &rec->parent_key);
3806         return btrfs_add_corrupt_extent_record(info, &key, start, len, 0);
3807 }
3808
3809 static int swap_values(struct btrfs_root *root, struct btrfs_path *path,
3810                        struct extent_buffer *buf, int slot)
3811 {
3812         if (btrfs_header_level(buf)) {
3813                 struct btrfs_key_ptr ptr1, ptr2;
3814
3815                 read_extent_buffer(buf, &ptr1, btrfs_node_key_ptr_offset(slot),
3816                                    sizeof(struct btrfs_key_ptr));
3817                 read_extent_buffer(buf, &ptr2,
3818                                    btrfs_node_key_ptr_offset(slot + 1),
3819                                    sizeof(struct btrfs_key_ptr));
3820                 write_extent_buffer(buf, &ptr1,
3821                                     btrfs_node_key_ptr_offset(slot + 1),
3822                                     sizeof(struct btrfs_key_ptr));
3823                 write_extent_buffer(buf, &ptr2,
3824                                     btrfs_node_key_ptr_offset(slot),
3825                                     sizeof(struct btrfs_key_ptr));
3826                 if (slot == 0) {
3827                         struct btrfs_disk_key key;
3828                         btrfs_node_key(buf, &key, 0);
3829                         btrfs_fixup_low_keys(root, path, &key,
3830                                              btrfs_header_level(buf) + 1);
3831                 }
3832         } else {
3833                 struct btrfs_item *item1, *item2;
3834                 struct btrfs_key k1, k2;
3835                 char *item1_data, *item2_data;
3836                 u32 item1_offset, item2_offset, item1_size, item2_size;
3837
3838                 item1 = btrfs_item_nr(slot);
3839                 item2 = btrfs_item_nr(slot + 1);
3840                 btrfs_item_key_to_cpu(buf, &k1, slot);
3841                 btrfs_item_key_to_cpu(buf, &k2, slot + 1);
3842                 item1_offset = btrfs_item_offset(buf, item1);
3843                 item2_offset = btrfs_item_offset(buf, item2);
3844                 item1_size = btrfs_item_size(buf, item1);
3845                 item2_size = btrfs_item_size(buf, item2);
3846
3847                 item1_data = malloc(item1_size);
3848                 if (!item1_data)
3849                         return -ENOMEM;
3850                 item2_data = malloc(item2_size);
3851                 if (!item2_data) {
3852                         free(item1_data);
3853                         return -ENOMEM;
3854                 }
3855
3856                 read_extent_buffer(buf, item1_data, item1_offset, item1_size);
3857                 read_extent_buffer(buf, item2_data, item2_offset, item2_size);
3858
3859                 write_extent_buffer(buf, item1_data, item2_offset, item2_size);
3860                 write_extent_buffer(buf, item2_data, item1_offset, item1_size);
3861                 free(item1_data);
3862                 free(item2_data);
3863
3864                 btrfs_set_item_offset(buf, item1, item2_offset);
3865                 btrfs_set_item_offset(buf, item2, item1_offset);
3866                 btrfs_set_item_size(buf, item1, item2_size);
3867                 btrfs_set_item_size(buf, item2, item1_size);
3868
3869                 path->slots[0] = slot;
3870                 btrfs_set_item_key_unsafe(root, path, &k2);
3871                 path->slots[0] = slot + 1;
3872                 btrfs_set_item_key_unsafe(root, path, &k1);
3873         }
3874         return 0;
3875 }
3876
3877 static int fix_key_order(struct btrfs_trans_handle *trans,
3878                          struct btrfs_root *root,
3879                          struct btrfs_path *path)
3880 {
3881         struct extent_buffer *buf;
3882         struct btrfs_key k1, k2;
3883         int i;
3884         int level = path->lowest_level;
3885         int ret = -EIO;
3886
3887         buf = path->nodes[level];
3888         for (i = 0; i < btrfs_header_nritems(buf) - 1; i++) {
3889                 if (level) {
3890                         btrfs_node_key_to_cpu(buf, &k1, i);
3891                         btrfs_node_key_to_cpu(buf, &k2, i + 1);
3892                 } else {
3893                         btrfs_item_key_to_cpu(buf, &k1, i);
3894                         btrfs_item_key_to_cpu(buf, &k2, i + 1);
3895                 }
3896                 if (btrfs_comp_cpu_keys(&k1, &k2) < 0)
3897                         continue;
3898                 ret = swap_values(root, path, buf, i);
3899                 if (ret)
3900                         break;
3901                 btrfs_mark_buffer_dirty(buf);
3902                 i = 0;
3903         }
3904         return ret;
3905 }
3906
3907 static int delete_bogus_item(struct btrfs_trans_handle *trans,
3908                              struct btrfs_root *root,
3909                              struct btrfs_path *path,
3910                              struct extent_buffer *buf, int slot)
3911 {
3912         struct btrfs_key key;
3913         int nritems = btrfs_header_nritems(buf);
3914
3915         btrfs_item_key_to_cpu(buf, &key, slot);
3916
3917         /* These are all the keys we can deal with missing. */
3918         if (key.type != BTRFS_DIR_INDEX_KEY &&
3919             key.type != BTRFS_EXTENT_ITEM_KEY &&
3920             key.type != BTRFS_METADATA_ITEM_KEY &&
3921             key.type != BTRFS_TREE_BLOCK_REF_KEY &&
3922             key.type != BTRFS_EXTENT_DATA_REF_KEY)
3923                 return -1;
3924
3925         printf("Deleting bogus item [%llu,%u,%llu] at slot %d on block %llu\n",
3926                (unsigned long long)key.objectid, key.type,
3927                (unsigned long long)key.offset, slot, buf->start);
3928         memmove_extent_buffer(buf, btrfs_item_nr_offset(slot),
3929                               btrfs_item_nr_offset(slot + 1),
3930                               sizeof(struct btrfs_item) *
3931                               (nritems - slot - 1));
3932         btrfs_set_header_nritems(buf, nritems - 1);
3933         if (slot == 0) {
3934                 struct btrfs_disk_key disk_key;
3935
3936                 btrfs_item_key(buf, &disk_key, 0);
3937                 btrfs_fixup_low_keys(root, path, &disk_key, 1);
3938         }
3939         btrfs_mark_buffer_dirty(buf);
3940         return 0;
3941 }
3942
3943 static int fix_item_offset(struct btrfs_trans_handle *trans,
3944                            struct btrfs_root *root,
3945                            struct btrfs_path *path)
3946 {
3947         struct extent_buffer *buf;
3948         int i;
3949         int ret = 0;
3950
3951         /* We should only get this for leaves */
3952         BUG_ON(path->lowest_level);
3953         buf = path->nodes[0];
3954 again:
3955         for (i = 0; i < btrfs_header_nritems(buf); i++) {
3956                 unsigned int shift = 0, offset;
3957
3958                 if (i == 0 && btrfs_item_end_nr(buf, i) !=
3959                     BTRFS_LEAF_DATA_SIZE(root)) {
3960                         if (btrfs_item_end_nr(buf, i) >
3961                             BTRFS_LEAF_DATA_SIZE(root)) {
3962                                 ret = delete_bogus_item(trans, root, path,
3963                                                         buf, i);
3964                                 if (!ret)
3965                                         goto again;
3966                                 fprintf(stderr, "item is off the end of the "
3967                                         "leaf, can't fix\n");
3968                                 ret = -EIO;
3969                                 break;
3970                         }
3971                         shift = BTRFS_LEAF_DATA_SIZE(root) -
3972                                 btrfs_item_end_nr(buf, i);
3973                 } else if (i > 0 && btrfs_item_end_nr(buf, i) !=
3974                            btrfs_item_offset_nr(buf, i - 1)) {
3975                         if (btrfs_item_end_nr(buf, i) >
3976                             btrfs_item_offset_nr(buf, i - 1)) {
3977                                 ret = delete_bogus_item(trans, root, path,
3978                                                         buf, i);
3979                                 if (!ret)
3980                                         goto again;
3981                                 fprintf(stderr, "items overlap, can't fix\n");
3982                                 ret = -EIO;
3983                                 break;
3984                         }
3985                         shift = btrfs_item_offset_nr(buf, i - 1) -
3986                                 btrfs_item_end_nr(buf, i);
3987                 }
3988                 if (!shift)
3989                         continue;
3990
3991                 printf("Shifting item nr %d by %u bytes in block %llu\n",
3992                        i, shift, (unsigned long long)buf->start);
3993                 offset = btrfs_item_offset_nr(buf, i);
3994                 memmove_extent_buffer(buf,
3995                                       btrfs_leaf_data(buf) + offset + shift,
3996                                       btrfs_leaf_data(buf) + offset,
3997                                       btrfs_item_size_nr(buf, i));
3998                 btrfs_set_item_offset(buf, btrfs_item_nr(i),
3999                                       offset + shift);
4000                 btrfs_mark_buffer_dirty(buf);
4001         }
4002
4003         /*
4004          * We may have moved things, in which case we want to exit so we don't
4005          * write those changes out.  Once we have proper abort functionality in
4006          * progs this can be changed to something nicer.
4007          */
4008         BUG_ON(ret);
4009         return ret;
4010 }
4011
4012 /*
4013  * Attempt to fix basic block failures.  If we can't fix it for whatever reason
4014  * then just return -EIO.
4015  */
4016 static int try_to_fix_bad_block(struct btrfs_root *root,
4017                                 struct extent_buffer *buf,
4018                                 enum btrfs_tree_block_status status)
4019 {
4020         struct btrfs_trans_handle *trans;
4021         struct ulist *roots;
4022         struct ulist_node *node;
4023         struct btrfs_root *search_root;
4024         struct btrfs_path *path;
4025         struct ulist_iterator iter;
4026         struct btrfs_key root_key, key;
4027         int ret;
4028
4029         if (status != BTRFS_TREE_BLOCK_BAD_KEY_ORDER &&
4030             status != BTRFS_TREE_BLOCK_INVALID_OFFSETS)
4031                 return -EIO;
4032
4033         path = btrfs_alloc_path();
4034         if (!path)
4035                 return -EIO;
4036
4037         ret = btrfs_find_all_roots(NULL, root->fs_info, buf->start,
4038                                    0, &roots);
4039         if (ret) {
4040                 btrfs_free_path(path);
4041                 return -EIO;
4042         }
4043
4044         ULIST_ITER_INIT(&iter);
4045         while ((node = ulist_next(roots, &iter))) {
4046                 root_key.objectid = node->val;
4047                 root_key.type = BTRFS_ROOT_ITEM_KEY;
4048                 root_key.offset = (u64)-1;
4049
4050                 search_root = btrfs_read_fs_root(root->fs_info, &root_key);
4051                 if (IS_ERR(root)) {
4052                         ret = -EIO;
4053                         break;
4054                 }
4055
4056
4057                 trans = btrfs_start_transaction(search_root, 0);
4058                 if (IS_ERR(trans)) {
4059                         ret = PTR_ERR(trans);
4060                         break;
4061                 }
4062
4063                 path->lowest_level = btrfs_header_level(buf);
4064                 path->skip_check_block = 1;
4065                 if (path->lowest_level)
4066                         btrfs_node_key_to_cpu(buf, &key, 0);
4067                 else
4068                         btrfs_item_key_to_cpu(buf, &key, 0);
4069                 ret = btrfs_search_slot(trans, search_root, &key, path, 0, 1);
4070                 if (ret) {
4071                         ret = -EIO;
4072                         btrfs_commit_transaction(trans, search_root);
4073                         break;
4074                 }
4075                 if (status == BTRFS_TREE_BLOCK_BAD_KEY_ORDER)
4076                         ret = fix_key_order(trans, search_root, path);
4077                 else if (status == BTRFS_TREE_BLOCK_INVALID_OFFSETS)
4078                         ret = fix_item_offset(trans, search_root, path);
4079                 if (ret) {
4080                         btrfs_commit_transaction(trans, search_root);
4081                         break;
4082                 }
4083                 btrfs_release_path(path);
4084                 btrfs_commit_transaction(trans, search_root);
4085         }
4086         ulist_free(roots);
4087         btrfs_free_path(path);
4088         return ret;
4089 }
4090
4091 static int check_block(struct btrfs_root *root,
4092                        struct cache_tree *extent_cache,
4093                        struct extent_buffer *buf, u64 flags)
4094 {
4095         struct extent_record *rec;
4096         struct cache_extent *cache;
4097         struct btrfs_key key;
4098         enum btrfs_tree_block_status status;
4099         int ret = 0;
4100         int level;
4101
4102         cache = lookup_cache_extent(extent_cache, buf->start, buf->len);
4103         if (!cache)
4104                 return 1;
4105         rec = container_of(cache, struct extent_record, cache);
4106         rec->generation = btrfs_header_generation(buf);
4107
4108         level = btrfs_header_level(buf);
4109         if (btrfs_header_nritems(buf) > 0) {
4110
4111                 if (level == 0)
4112                         btrfs_item_key_to_cpu(buf, &key, 0);
4113                 else
4114                         btrfs_node_key_to_cpu(buf, &key, 0);
4115
4116                 rec->info_objectid = key.objectid;
4117         }
4118         rec->info_level = level;
4119
4120         if (btrfs_is_leaf(buf))
4121                 status = btrfs_check_leaf(root, &rec->parent_key, buf);
4122         else
4123                 status = btrfs_check_node(root, &rec->parent_key, buf);
4124
4125         if (status != BTRFS_TREE_BLOCK_CLEAN) {
4126                 if (repair)
4127                         status = try_to_fix_bad_block(root, buf, status);
4128                 if (status != BTRFS_TREE_BLOCK_CLEAN) {
4129                         ret = -EIO;
4130                         fprintf(stderr, "bad block %llu\n",
4131                                 (unsigned long long)buf->start);
4132                 } else {
4133                         /*
4134                          * Signal to callers we need to start the scan over
4135                          * again since we'll have cow'ed blocks.
4136                          */
4137                         ret = -EAGAIN;
4138                 }
4139         } else {
4140                 rec->content_checked = 1;
4141                 if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4142                         rec->owner_ref_checked = 1;
4143                 else {
4144                         ret = check_owner_ref(root, rec, buf);
4145                         if (!ret)
4146                                 rec->owner_ref_checked = 1;
4147                 }
4148         }
4149         if (!ret)
4150                 maybe_free_extent_rec(extent_cache, rec);
4151         return ret;
4152 }
4153
4154 static struct tree_backref *find_tree_backref(struct extent_record *rec,
4155                                                 u64 parent, u64 root)
4156 {
4157         struct list_head *cur = rec->backrefs.next;
4158         struct extent_backref *node;
4159         struct tree_backref *back;
4160
4161         while(cur != &rec->backrefs) {
4162                 node = list_entry(cur, struct extent_backref, list);
4163                 cur = cur->next;
4164                 if (node->is_data)
4165                         continue;
4166                 back = (struct tree_backref *)node;
4167                 if (parent > 0) {
4168                         if (!node->full_backref)
4169                                 continue;
4170                         if (parent == back->parent)
4171                                 return back;
4172                 } else {
4173                         if (node->full_backref)
4174                                 continue;
4175                         if (back->root == root)
4176                                 return back;
4177                 }
4178         }
4179         return NULL;
4180 }
4181
4182 static struct tree_backref *alloc_tree_backref(struct extent_record *rec,
4183                                                 u64 parent, u64 root)
4184 {
4185         struct tree_backref *ref = malloc(sizeof(*ref));
4186         memset(&ref->node, 0, sizeof(ref->node));
4187         if (parent > 0) {
4188                 ref->parent = parent;
4189                 ref->node.full_backref = 1;
4190         } else {
4191                 ref->root = root;
4192                 ref->node.full_backref = 0;
4193         }
4194         list_add_tail(&ref->node.list, &rec->backrefs);
4195
4196         return ref;
4197 }
4198
4199 static struct data_backref *find_data_backref(struct extent_record *rec,
4200                                                 u64 parent, u64 root,
4201                                                 u64 owner, u64 offset,
4202                                                 int found_ref,
4203                                                 u64 disk_bytenr, u64 bytes)
4204 {
4205         struct list_head *cur = rec->backrefs.next;
4206         struct extent_backref *node;
4207         struct data_backref *back;
4208
4209         while(cur != &rec->backrefs) {
4210                 node = list_entry(cur, struct extent_backref, list);
4211                 cur = cur->next;
4212                 if (!node->is_data)
4213                         continue;
4214                 back = (struct data_backref *)node;
4215                 if (parent > 0) {
4216                         if (!node->full_backref)
4217                                 continue;
4218                         if (parent == back->parent)
4219                                 return back;
4220                 } else {
4221                         if (node->full_backref)
4222                                 continue;
4223                         if (back->root == root && back->owner == owner &&
4224                             back->offset == offset) {
4225                                 if (found_ref && node->found_ref &&
4226                                     (back->bytes != bytes ||
4227                                     back->disk_bytenr != disk_bytenr))
4228                                         continue;
4229                                 return back;
4230                         }
4231                 }
4232         }
4233         return NULL;
4234 }
4235
4236 static struct data_backref *alloc_data_backref(struct extent_record *rec,
4237                                                 u64 parent, u64 root,
4238                                                 u64 owner, u64 offset,
4239                                                 u64 max_size)
4240 {
4241         struct data_backref *ref = malloc(sizeof(*ref));
4242         memset(&ref->node, 0, sizeof(ref->node));
4243         ref->node.is_data = 1;
4244
4245         if (parent > 0) {
4246                 ref->parent = parent;
4247                 ref->owner = 0;
4248                 ref->offset = 0;
4249                 ref->node.full_backref = 1;
4250         } else {
4251                 ref->root = root;
4252                 ref->owner = owner;
4253                 ref->offset = offset;
4254                 ref->node.full_backref = 0;
4255         }
4256         ref->bytes = max_size;
4257         ref->found_ref = 0;
4258         ref->num_refs = 0;
4259         list_add_tail(&ref->node.list, &rec->backrefs);
4260         if (max_size > rec->max_size)
4261                 rec->max_size = max_size;
4262         return ref;
4263 }
4264
4265 static int add_extent_rec(struct cache_tree *extent_cache,
4266                           struct btrfs_key *parent_key, u64 parent_gen,
4267                           u64 start, u64 nr, u64 extent_item_refs,
4268                           int is_root, int inc_ref, int set_checked,
4269                           int metadata, int extent_rec, u64 max_size)
4270 {
4271         struct extent_record *rec;
4272         struct cache_extent *cache;
4273         int ret = 0;
4274         int dup = 0;
4275
4276         cache = lookup_cache_extent(extent_cache, start, nr);
4277         if (cache) {
4278                 rec = container_of(cache, struct extent_record, cache);
4279                 if (inc_ref)
4280                         rec->refs++;
4281                 if (rec->nr == 1)
4282                         rec->nr = max(nr, max_size);
4283
4284                 /*
4285                  * We need to make sure to reset nr to whatever the extent
4286                  * record says was the real size, this way we can compare it to
4287                  * the backrefs.
4288                  */
4289                 if (extent_rec) {
4290                         if (start != rec->start || rec->found_rec) {
4291                                 struct extent_record *tmp;
4292
4293                                 dup = 1;
4294                                 if (list_empty(&rec->list))
4295                                         list_add_tail(&rec->list,
4296                                                       &duplicate_extents);
4297
4298                                 /*
4299                                  * We have to do this song and dance in case we
4300                                  * find an extent record that falls inside of
4301                                  * our current extent record but does not have
4302                                  * the same objectid.
4303                                  */
4304                                 tmp = malloc(sizeof(*tmp));
4305                                 if (!tmp)
4306                                         return -ENOMEM;
4307                                 tmp->start = start;
4308                                 tmp->max_size = max_size;
4309                                 tmp->nr = nr;
4310                                 tmp->found_rec = 1;
4311                                 tmp->metadata = metadata;
4312                                 tmp->extent_item_refs = extent_item_refs;
4313                                 INIT_LIST_HEAD(&tmp->list);
4314                                 list_add_tail(&tmp->list, &rec->dups);
4315                                 rec->num_duplicates++;
4316                         } else {
4317                                 rec->nr = nr;
4318                                 rec->found_rec = 1;
4319                         }
4320                 }
4321
4322                 if (extent_item_refs && !dup) {
4323                         if (rec->extent_item_refs) {
4324                                 fprintf(stderr, "block %llu rec "
4325                                         "extent_item_refs %llu, passed %llu\n",
4326                                         (unsigned long long)start,
4327                                         (unsigned long long)
4328                                                         rec->extent_item_refs,
4329                                         (unsigned long long)extent_item_refs);
4330                         }
4331                         rec->extent_item_refs = extent_item_refs;
4332                 }
4333                 if (is_root)
4334                         rec->is_root = 1;
4335                 if (set_checked) {
4336                         rec->content_checked = 1;
4337                         rec->owner_ref_checked = 1;
4338                 }
4339
4340                 if (parent_key)
4341                         btrfs_cpu_key_to_disk(&rec->parent_key, parent_key);
4342                 if (parent_gen)
4343                         rec->parent_generation = parent_gen;
4344
4345                 if (rec->max_size < max_size)
4346                         rec->max_size = max_size;
4347
4348                 maybe_free_extent_rec(extent_cache, rec);
4349                 return ret;
4350         }
4351         rec = malloc(sizeof(*rec));
4352         rec->start = start;
4353         rec->max_size = max_size;
4354         rec->nr = max(nr, max_size);
4355         rec->found_rec = !!extent_rec;
4356         rec->content_checked = 0;
4357         rec->owner_ref_checked = 0;
4358         rec->num_duplicates = 0;
4359         rec->metadata = metadata;
4360         rec->flag_block_full_backref = -1;
4361         rec->bad_full_backref = 0;
4362         INIT_LIST_HEAD(&rec->backrefs);
4363         INIT_LIST_HEAD(&rec->dups);
4364         INIT_LIST_HEAD(&rec->list);
4365
4366         if (is_root)
4367                 rec->is_root = 1;
4368         else
4369                 rec->is_root = 0;
4370
4371         if (inc_ref)
4372                 rec->refs = 1;
4373         else
4374                 rec->refs = 0;
4375
4376         if (extent_item_refs)
4377                 rec->extent_item_refs = extent_item_refs;
4378         else
4379                 rec->extent_item_refs = 0;
4380
4381         if (parent_key)
4382                 btrfs_cpu_key_to_disk(&rec->parent_key, parent_key);
4383         else
4384                 memset(&rec->parent_key, 0, sizeof(*parent_key));
4385
4386         if (parent_gen)
4387                 rec->parent_generation = parent_gen;
4388         else
4389                 rec->parent_generation = 0;
4390
4391         rec->cache.start = start;
4392         rec->cache.size = nr;
4393         ret = insert_cache_extent(extent_cache, &rec->cache);
4394         BUG_ON(ret);
4395         bytes_used += nr;
4396         if (set_checked) {
4397                 rec->content_checked = 1;
4398                 rec->owner_ref_checked = 1;
4399         }
4400         return ret;
4401 }
4402
4403 static int add_tree_backref(struct cache_tree *extent_cache, u64 bytenr,
4404                             u64 parent, u64 root, int found_ref)
4405 {
4406         struct extent_record *rec;
4407         struct tree_backref *back;
4408         struct cache_extent *cache;
4409
4410         cache = lookup_cache_extent(extent_cache, bytenr, 1);
4411         if (!cache) {
4412                 add_extent_rec(extent_cache, NULL, 0, bytenr,
4413                                1, 0, 0, 0, 0, 1, 0, 0);
4414                 cache = lookup_cache_extent(extent_cache, bytenr, 1);
4415                 if (!cache)
4416                         abort();
4417         }
4418
4419         rec = container_of(cache, struct extent_record, cache);
4420         if (rec->start != bytenr) {
4421                 abort();
4422         }
4423
4424         back = find_tree_backref(rec, parent, root);
4425         if (!back)
4426                 back = alloc_tree_backref(rec, parent, root);
4427
4428         if (found_ref) {
4429                 if (back->node.found_ref) {
4430                         fprintf(stderr, "Extent back ref already exists "
4431                                 "for %llu parent %llu root %llu \n",
4432                                 (unsigned long long)bytenr,
4433                                 (unsigned long long)parent,
4434                                 (unsigned long long)root);
4435                 }
4436                 back->node.found_ref = 1;
4437         } else {
4438                 if (back->node.found_extent_tree) {
4439                         fprintf(stderr, "Extent back ref already exists "
4440                                 "for %llu parent %llu root %llu \n",
4441                                 (unsigned long long)bytenr,
4442                                 (unsigned long long)parent,
4443                                 (unsigned long long)root);
4444                 }
4445                 back->node.found_extent_tree = 1;
4446         }
4447         maybe_free_extent_rec(extent_cache, rec);
4448         return 0;
4449 }
4450
4451 static int add_data_backref(struct cache_tree *extent_cache, u64 bytenr,
4452                             u64 parent, u64 root, u64 owner, u64 offset,
4453                             u32 num_refs, int found_ref, u64 max_size)
4454 {
4455         struct extent_record *rec;
4456         struct data_backref *back;
4457         struct cache_extent *cache;
4458
4459         cache = lookup_cache_extent(extent_cache, bytenr, 1);
4460         if (!cache) {
4461                 add_extent_rec(extent_cache, NULL, 0, bytenr, 1, 0, 0, 0, 0,
4462                                0, 0, max_size);
4463                 cache = lookup_cache_extent(extent_cache, bytenr, 1);
4464                 if (!cache)
4465                         abort();
4466         }
4467
4468         rec = container_of(cache, struct extent_record, cache);
4469         if (rec->max_size < max_size)
4470                 rec->max_size = max_size;
4471
4472         /*
4473          * If found_ref is set then max_size is the real size and must match the
4474          * existing refs.  So if we have already found a ref then we need to
4475          * make sure that this ref matches the existing one, otherwise we need
4476          * to add a new backref so we can notice that the backrefs don't match
4477          * and we need to figure out who is telling the truth.  This is to
4478          * account for that awful fsync bug I introduced where we'd end up with
4479          * a btrfs_file_extent_item that would have its length include multiple
4480          * prealloc extents or point inside of a prealloc extent.
4481          */
4482         back = find_data_backref(rec, parent, root, owner, offset, found_ref,
4483                                  bytenr, max_size);
4484         if (!back)
4485                 back = alloc_data_backref(rec, parent, root, owner, offset,
4486                                           max_size);
4487
4488         if (found_ref) {
4489                 BUG_ON(num_refs != 1);
4490                 if (back->node.found_ref)
4491                         BUG_ON(back->bytes != max_size);
4492                 back->node.found_ref = 1;
4493                 back->found_ref += 1;
4494                 back->bytes = max_size;
4495                 back->disk_bytenr = bytenr;
4496                 rec->refs += 1;
4497                 rec->content_checked = 1;
4498                 rec->owner_ref_checked = 1;
4499         } else {
4500                 if (back->node.found_extent_tree) {
4501                         fprintf(stderr, "Extent back ref already exists "
4502                                 "for %llu parent %llu root %llu "
4503                                 "owner %llu offset %llu num_refs %lu\n",
4504                                 (unsigned long long)bytenr,
4505                                 (unsigned long long)parent,
4506                                 (unsigned long long)root,
4507                                 (unsigned long long)owner,
4508                                 (unsigned long long)offset,
4509                                 (unsigned long)num_refs);
4510                 }
4511                 back->num_refs = num_refs;
4512                 back->node.found_extent_tree = 1;
4513         }
4514         maybe_free_extent_rec(extent_cache, rec);
4515         return 0;
4516 }
4517
4518 static int add_pending(struct cache_tree *pending,
4519                        struct cache_tree *seen, u64 bytenr, u32 size)
4520 {
4521         int ret;
4522         ret = add_cache_extent(seen, bytenr, size);
4523         if (ret)
4524                 return ret;
4525         add_cache_extent(pending, bytenr, size);
4526         return 0;
4527 }
4528
4529 static int pick_next_pending(struct cache_tree *pending,
4530                         struct cache_tree *reada,
4531                         struct cache_tree *nodes,
4532                         u64 last, struct block_info *bits, int bits_nr,
4533                         int *reada_bits)
4534 {
4535         unsigned long node_start = last;
4536         struct cache_extent *cache;
4537         int ret;
4538
4539         cache = search_cache_extent(reada, 0);
4540         if (cache) {
4541                 bits[0].start = cache->start;
4542                 bits[0].size = cache->size;
4543                 *reada_bits = 1;
4544                 return 1;
4545         }
4546         *reada_bits = 0;
4547         if (node_start > 32768)
4548                 node_start -= 32768;
4549
4550         cache = search_cache_extent(nodes, node_start);
4551         if (!cache)
4552                 cache = search_cache_extent(nodes, 0);
4553
4554         if (!cache) {
4555                  cache = search_cache_extent(pending, 0);
4556                  if (!cache)
4557                          return 0;
4558                  ret = 0;
4559                  do {
4560                          bits[ret].start = cache->start;
4561                          bits[ret].size = cache->size;
4562                          cache = next_cache_extent(cache);
4563                          ret++;
4564                  } while (cache && ret < bits_nr);
4565                  return ret;
4566         }
4567
4568         ret = 0;
4569         do {
4570                 bits[ret].start = cache->start;
4571                 bits[ret].size = cache->size;
4572                 cache = next_cache_extent(cache);
4573                 ret++;
4574         } while (cache && ret < bits_nr);
4575
4576         if (bits_nr - ret > 8) {
4577                 u64 lookup = bits[0].start + bits[0].size;
4578                 struct cache_extent *next;
4579                 next = search_cache_extent(pending, lookup);
4580                 while(next) {
4581                         if (next->start - lookup > 32768)
4582                                 break;
4583                         bits[ret].start = next->start;
4584                         bits[ret].size = next->size;
4585                         lookup = next->start + next->size;
4586                         ret++;
4587                         if (ret == bits_nr)
4588                                 break;
4589                         next = next_cache_extent(next);
4590                         if (!next)
4591                                 break;
4592                 }
4593         }
4594         return ret;
4595 }
4596
4597 static void free_chunk_record(struct cache_extent *cache)
4598 {
4599         struct chunk_record *rec;
4600
4601         rec = container_of(cache, struct chunk_record, cache);
4602         list_del_init(&rec->list);
4603         list_del_init(&rec->dextents);
4604         free(rec);
4605 }
4606
4607 void free_chunk_cache_tree(struct cache_tree *chunk_cache)
4608 {
4609         cache_tree_free_extents(chunk_cache, free_chunk_record);
4610 }
4611
4612 static void free_device_record(struct rb_node *node)
4613 {
4614         struct device_record *rec;
4615
4616         rec = container_of(node, struct device_record, node);
4617         free(rec);
4618 }
4619
4620 FREE_RB_BASED_TREE(device_cache, free_device_record);
4621
4622 int insert_block_group_record(struct block_group_tree *tree,
4623                               struct block_group_record *bg_rec)
4624 {
4625         int ret;
4626
4627         ret = insert_cache_extent(&tree->tree, &bg_rec->cache);
4628         if (ret)
4629                 return ret;
4630
4631         list_add_tail(&bg_rec->list, &tree->block_groups);
4632         return 0;
4633 }
4634
4635 static void free_block_group_record(struct cache_extent *cache)
4636 {
4637         struct block_group_record *rec;
4638
4639         rec = container_of(cache, struct block_group_record, cache);
4640         list_del_init(&rec->list);
4641         free(rec);
4642 }
4643
4644 void free_block_group_tree(struct block_group_tree *tree)
4645 {
4646         cache_tree_free_extents(&tree->tree, free_block_group_record);
4647 }
4648
4649 int insert_device_extent_record(struct device_extent_tree *tree,
4650                                 struct device_extent_record *de_rec)
4651 {
4652         int ret;
4653
4654         /*
4655          * Device extent is a bit different from the other extents, because
4656          * the extents which belong to the different devices may have the
4657          * same start and size, so we need use the special extent cache
4658          * search/insert functions.
4659          */
4660         ret = insert_cache_extent2(&tree->tree, &de_rec->cache);
4661         if (ret)
4662                 return ret;
4663
4664         list_add_tail(&de_rec->chunk_list, &tree->no_chunk_orphans);
4665         list_add_tail(&de_rec->device_list, &tree->no_device_orphans);
4666         return 0;
4667 }
4668
4669 static void free_device_extent_record(struct cache_extent *cache)
4670 {
4671         struct device_extent_record *rec;
4672
4673         rec = container_of(cache, struct device_extent_record, cache);
4674         if (!list_empty(&rec->chunk_list))
4675                 list_del_init(&rec->chunk_list);
4676         if (!list_empty(&rec->device_list))
4677                 list_del_init(&rec->device_list);
4678         free(rec);
4679 }
4680
4681 void free_device_extent_tree(struct device_extent_tree *tree)
4682 {
4683         cache_tree_free_extents(&tree->tree, free_device_extent_record);
4684 }
4685
4686 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4687 static int process_extent_ref_v0(struct cache_tree *extent_cache,
4688                                  struct extent_buffer *leaf, int slot)
4689 {
4690         struct btrfs_extent_ref_v0 *ref0;
4691         struct btrfs_key key;
4692
4693         btrfs_item_key_to_cpu(leaf, &key, slot);
4694         ref0 = btrfs_item_ptr(leaf, slot, struct btrfs_extent_ref_v0);
4695         if (btrfs_ref_objectid_v0(leaf, ref0) < BTRFS_FIRST_FREE_OBJECTID) {
4696                 add_tree_backref(extent_cache, key.objectid, key.offset, 0, 0);
4697         } else {
4698                 add_data_backref(extent_cache, key.objectid, key.offset, 0,
4699                                  0, 0, btrfs_ref_count_v0(leaf, ref0), 0, 0);
4700         }
4701         return 0;
4702 }
4703 #endif
4704
4705 struct chunk_record *btrfs_new_chunk_record(struct extent_buffer *leaf,
4706                                             struct btrfs_key *key,
4707                                             int slot)
4708 {
4709         struct btrfs_chunk *ptr;
4710         struct chunk_record *rec;
4711         int num_stripes, i;
4712
4713         ptr = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
4714         num_stripes = btrfs_chunk_num_stripes(leaf, ptr);
4715
4716         rec = malloc(btrfs_chunk_record_size(num_stripes));
4717         if (!rec) {
4718                 fprintf(stderr, "memory allocation failed\n");
4719                 exit(-1);
4720         }
4721
4722         memset(rec, 0, btrfs_chunk_record_size(num_stripes));
4723
4724         INIT_LIST_HEAD(&rec->list);
4725         INIT_LIST_HEAD(&rec->dextents);
4726         rec->bg_rec = NULL;
4727
4728         rec->cache.start = key->offset;
4729         rec->cache.size = btrfs_chunk_length(leaf, ptr);
4730
4731         rec->generation = btrfs_header_generation(leaf);
4732
4733         rec->objectid = key->objectid;
4734         rec->type = key->type;
4735         rec->offset = key->offset;
4736
4737         rec->length = rec->cache.size;
4738         rec->owner = btrfs_chunk_owner(leaf, ptr);
4739         rec->stripe_len = btrfs_chunk_stripe_len(leaf, ptr);
4740         rec->type_flags = btrfs_chunk_type(leaf, ptr);
4741         rec->io_width = btrfs_chunk_io_width(leaf, ptr);
4742         rec->io_align = btrfs_chunk_io_align(leaf, ptr);
4743         rec->sector_size = btrfs_chunk_sector_size(leaf, ptr);
4744         rec->num_stripes = num_stripes;
4745         rec->sub_stripes = btrfs_chunk_sub_stripes(leaf, ptr);
4746
4747         for (i = 0; i < rec->num_stripes; ++i) {
4748                 rec->stripes[i].devid =
4749                         btrfs_stripe_devid_nr(leaf, ptr, i);
4750                 rec->stripes[i].offset =
4751                         btrfs_stripe_offset_nr(leaf, ptr, i);
4752                 read_extent_buffer(leaf, rec->stripes[i].dev_uuid,
4753                                 (unsigned long)btrfs_stripe_dev_uuid_nr(ptr, i),
4754                                 BTRFS_UUID_SIZE);
4755         }
4756
4757         return rec;
4758 }
4759
4760 static int process_chunk_item(struct cache_tree *chunk_cache,
4761                               struct btrfs_key *key, struct extent_buffer *eb,
4762                               int slot)
4763 {
4764         struct chunk_record *rec;
4765         int ret = 0;
4766
4767         rec = btrfs_new_chunk_record(eb, key, slot);
4768         ret = insert_cache_extent(chunk_cache, &rec->cache);
4769         if (ret) {
4770                 fprintf(stderr, "Chunk[%llu, %llu] existed.\n",
4771                         rec->offset, rec->length);
4772                 free(rec);
4773         }
4774
4775         return ret;
4776 }
4777
4778 static int process_device_item(struct rb_root *dev_cache,
4779                 struct btrfs_key *key, struct extent_buffer *eb, int slot)
4780 {
4781         struct btrfs_dev_item *ptr;
4782         struct device_record *rec;
4783         int ret = 0;
4784
4785         ptr = btrfs_item_ptr(eb,
4786                 slot, struct btrfs_dev_item);
4787
4788         rec = malloc(sizeof(*rec));
4789         if (!rec) {
4790                 fprintf(stderr, "memory allocation failed\n");
4791                 return -ENOMEM;
4792         }
4793
4794         rec->devid = key->offset;
4795         rec->generation = btrfs_header_generation(eb);
4796
4797         rec->objectid = key->objectid;
4798         rec->type = key->type;
4799         rec->offset = key->offset;
4800
4801         rec->devid = btrfs_device_id(eb, ptr);
4802         rec->total_byte = btrfs_device_total_bytes(eb, ptr);
4803         rec->byte_used = btrfs_device_bytes_used(eb, ptr);
4804
4805         ret = rb_insert(dev_cache, &rec->node, device_record_compare);
4806         if (ret) {
4807                 fprintf(stderr, "Device[%llu] existed.\n", rec->devid);
4808                 free(rec);
4809         }
4810
4811         return ret;
4812 }
4813
4814 struct block_group_record *
4815 btrfs_new_block_group_record(struct extent_buffer *leaf, struct btrfs_key *key,
4816                              int slot)
4817 {
4818         struct btrfs_block_group_item *ptr;
4819         struct block_group_record *rec;
4820
4821         rec = malloc(sizeof(*rec));
4822         if (!rec) {
4823                 fprintf(stderr, "memory allocation failed\n");
4824                 exit(-1);
4825         }
4826         memset(rec, 0, sizeof(*rec));
4827
4828         rec->cache.start = key->objectid;
4829         rec->cache.size = key->offset;
4830
4831         rec->generation = btrfs_header_generation(leaf);
4832
4833         rec->objectid = key->objectid;
4834         rec->type = key->type;
4835         rec->offset = key->offset;
4836
4837         ptr = btrfs_item_ptr(leaf, slot, struct btrfs_block_group_item);
4838         rec->flags = btrfs_disk_block_group_flags(leaf, ptr);
4839
4840         INIT_LIST_HEAD(&rec->list);
4841
4842         return rec;
4843 }
4844
4845 static int process_block_group_item(struct block_group_tree *block_group_cache,
4846                                     struct btrfs_key *key,
4847                                     struct extent_buffer *eb, int slot)
4848 {
4849         struct block_group_record *rec;
4850         int ret = 0;
4851
4852         rec = btrfs_new_block_group_record(eb, key, slot);
4853         ret = insert_block_group_record(block_group_cache, rec);
4854         if (ret) {
4855                 fprintf(stderr, "Block Group[%llu, %llu] existed.\n",
4856                         rec->objectid, rec->offset);
4857                 free(rec);
4858         }
4859
4860         return ret;
4861 }
4862
4863 struct device_extent_record *
4864 btrfs_new_device_extent_record(struct extent_buffer *leaf,
4865                                struct btrfs_key *key, int slot)
4866 {
4867         struct device_extent_record *rec;
4868         struct btrfs_dev_extent *ptr;
4869
4870         rec = malloc(sizeof(*rec));
4871         if (!rec) {
4872                 fprintf(stderr, "memory allocation failed\n");
4873                 exit(-1);
4874         }
4875         memset(rec, 0, sizeof(*rec));
4876
4877         rec->cache.objectid = key->objectid;
4878         rec->cache.start = key->offset;
4879
4880         rec->generation = btrfs_header_generation(leaf);
4881
4882         rec->objectid = key->objectid;
4883         rec->type = key->type;
4884         rec->offset = key->offset;
4885
4886         ptr = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
4887         rec->chunk_objecteid =
4888                 btrfs_dev_extent_chunk_objectid(leaf, ptr);
4889         rec->chunk_offset =
4890                 btrfs_dev_extent_chunk_offset(leaf, ptr);
4891         rec->length = btrfs_dev_extent_length(leaf, ptr);
4892         rec->cache.size = rec->length;
4893
4894         INIT_LIST_HEAD(&rec->chunk_list);
4895         INIT_LIST_HEAD(&rec->device_list);
4896
4897         return rec;
4898 }
4899
4900 static int
4901 process_device_extent_item(struct device_extent_tree *dev_extent_cache,
4902                            struct btrfs_key *key, struct extent_buffer *eb,
4903                            int slot)
4904 {
4905         struct device_extent_record *rec;
4906         int ret;
4907
4908         rec = btrfs_new_device_extent_record(eb, key, slot);
4909         ret = insert_device_extent_record(dev_extent_cache, rec);
4910         if (ret) {
4911                 fprintf(stderr,
4912                         "Device extent[%llu, %llu, %llu] existed.\n",
4913                         rec->objectid, rec->offset, rec->length);
4914                 free(rec);
4915         }
4916
4917         return ret;
4918 }
4919
4920 static int process_extent_item(struct btrfs_root *root,
4921                                struct cache_tree *extent_cache,
4922                                struct extent_buffer *eb, int slot)
4923 {
4924         struct btrfs_extent_item *ei;
4925         struct btrfs_extent_inline_ref *iref;
4926         struct btrfs_extent_data_ref *dref;
4927         struct btrfs_shared_data_ref *sref;
4928         struct btrfs_key key;
4929         unsigned long end;
4930         unsigned long ptr;
4931         int type;
4932         u32 item_size = btrfs_item_size_nr(eb, slot);
4933         u64 refs = 0;
4934         u64 offset;
4935         u64 num_bytes;
4936         int metadata = 0;
4937
4938         btrfs_item_key_to_cpu(eb, &key, slot);
4939
4940         if (key.type == BTRFS_METADATA_ITEM_KEY) {
4941                 metadata = 1;
4942                 num_bytes = root->leafsize;
4943         } else {
4944                 num_bytes = key.offset;
4945         }
4946
4947         if (item_size < sizeof(*ei)) {
4948 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4949                 struct btrfs_extent_item_v0 *ei0;
4950                 BUG_ON(item_size != sizeof(*ei0));
4951                 ei0 = btrfs_item_ptr(eb, slot, struct btrfs_extent_item_v0);
4952                 refs = btrfs_extent_refs_v0(eb, ei0);
4953 #else
4954                 BUG();
4955 #endif
4956                 return add_extent_rec(extent_cache, NULL, 0, key.objectid,
4957                                       num_bytes, refs, 0, 0, 0, metadata, 1,
4958                                       num_bytes);
4959         }
4960
4961         ei = btrfs_item_ptr(eb, slot, struct btrfs_extent_item);
4962         refs = btrfs_extent_refs(eb, ei);
4963
4964         add_extent_rec(extent_cache, NULL, 0, key.objectid, num_bytes,
4965                        refs, 0, 0, 0, metadata, 1, num_bytes);
4966
4967         ptr = (unsigned long)(ei + 1);
4968         if (btrfs_extent_flags(eb, ei) & BTRFS_EXTENT_FLAG_TREE_BLOCK &&
4969             key.type == BTRFS_EXTENT_ITEM_KEY)
4970                 ptr += sizeof(struct btrfs_tree_block_info);
4971
4972         end = (unsigned long)ei + item_size;
4973         while (ptr < end) {
4974                 iref = (struct btrfs_extent_inline_ref *)ptr;
4975                 type = btrfs_extent_inline_ref_type(eb, iref);
4976                 offset = btrfs_extent_inline_ref_offset(eb, iref);
4977                 switch (type) {
4978                 case BTRFS_TREE_BLOCK_REF_KEY:
4979                         add_tree_backref(extent_cache, key.objectid,
4980                                          0, offset, 0);
4981                         break;
4982                 case BTRFS_SHARED_BLOCK_REF_KEY:
4983                         add_tree_backref(extent_cache, key.objectid,
4984                                          offset, 0, 0);
4985                         break;
4986                 case BTRFS_EXTENT_DATA_REF_KEY:
4987                         dref = (struct btrfs_extent_data_ref *)(&iref->offset);
4988                         add_data_backref(extent_cache, key.objectid, 0,
4989                                         btrfs_extent_data_ref_root(eb, dref),
4990                                         btrfs_extent_data_ref_objectid(eb,
4991                                                                        dref),
4992                                         btrfs_extent_data_ref_offset(eb, dref),
4993                                         btrfs_extent_data_ref_count(eb, dref),
4994                                         0, num_bytes);
4995                         break;
4996                 case BTRFS_SHARED_DATA_REF_KEY:
4997                         sref = (struct btrfs_shared_data_ref *)(iref + 1);
4998                         add_data_backref(extent_cache, key.objectid, offset,
4999                                         0, 0, 0,
5000                                         btrfs_shared_data_ref_count(eb, sref),
5001                                         0, num_bytes);
5002                         break;
5003                 default:
5004                         fprintf(stderr, "corrupt extent record: key %Lu %u %Lu\n",
5005                                 key.objectid, key.type, num_bytes);
5006                         goto out;
5007                 }
5008                 ptr += btrfs_extent_inline_ref_size(type);
5009         }
5010         WARN_ON(ptr > end);
5011 out:
5012         return 0;
5013 }
5014
5015 static int check_cache_range(struct btrfs_root *root,
5016                              struct btrfs_block_group_cache *cache,
5017                              u64 offset, u64 bytes)
5018 {
5019         struct btrfs_free_space *entry;
5020         u64 *logical;
5021         u64 bytenr;
5022         int stripe_len;
5023         int i, nr, ret;
5024
5025         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
5026                 bytenr = btrfs_sb_offset(i);
5027                 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
5028                                        cache->key.objectid, bytenr, 0,
5029                                        &logical, &nr, &stripe_len);
5030                 if (ret)
5031                         return ret;
5032
5033                 while (nr--) {
5034                         if (logical[nr] + stripe_len <= offset)
5035                                 continue;
5036                         if (offset + bytes <= logical[nr])
5037                                 continue;
5038                         if (logical[nr] == offset) {
5039                                 if (stripe_len >= bytes) {
5040                                         kfree(logical);
5041                                         return 0;
5042                                 }
5043                                 bytes -= stripe_len;
5044                                 offset += stripe_len;
5045                         } else if (logical[nr] < offset) {
5046                                 if (logical[nr] + stripe_len >=
5047                                     offset + bytes) {
5048                                         kfree(logical);
5049                                         return 0;
5050                                 }
5051                                 bytes = (offset + bytes) -
5052                                         (logical[nr] + stripe_len);
5053                                 offset = logical[nr] + stripe_len;
5054                         } else {
5055                                 /*
5056                                  * Could be tricky, the super may land in the
5057                                  * middle of the area we're checking.  First
5058                                  * check the easiest case, it's at the end.
5059                                  */
5060                                 if (logical[nr] + stripe_len >=
5061                                     bytes + offset) {
5062                                         bytes = logical[nr] - offset;
5063                                         continue;
5064                                 }
5065
5066                                 /* Check the left side */
5067                                 ret = check_cache_range(root, cache,
5068                                                         offset,
5069                                                         logical[nr] - offset);
5070                                 if (ret) {
5071                                         kfree(logical);
5072                                         return ret;
5073                                 }
5074
5075                                 /* Now we continue with the right side */
5076                                 bytes = (offset + bytes) -
5077                                         (logical[nr] + stripe_len);
5078                                 offset = logical[nr] + stripe_len;
5079                         }
5080                 }
5081
5082                 kfree(logical);
5083         }
5084
5085         entry = btrfs_find_free_space(cache->free_space_ctl, offset, bytes);
5086         if (!entry) {
5087                 fprintf(stderr, "There is no free space entry for %Lu-%Lu\n",
5088                         offset, offset+bytes);
5089                 return -EINVAL;
5090         }
5091
5092         if (entry->offset != offset) {
5093                 fprintf(stderr, "Wanted offset %Lu, found %Lu\n", offset,
5094                         entry->offset);
5095                 return -EINVAL;
5096         }
5097
5098         if (entry->bytes != bytes) {
5099                 fprintf(stderr, "Wanted bytes %Lu, found %Lu for off %Lu\n",
5100                         bytes, entry->bytes, offset);
5101                 return -EINVAL;
5102         }
5103
5104         unlink_free_space(cache->free_space_ctl, entry);
5105         free(entry);
5106         return 0;
5107 }
5108
5109 static int verify_space_cache(struct btrfs_root *root,
5110                               struct btrfs_block_group_cache *cache)
5111 {
5112         struct btrfs_path *path;
5113         struct extent_buffer *leaf;
5114         struct btrfs_key key;
5115         u64 last;
5116         int ret = 0;
5117
5118         path = btrfs_alloc_path();
5119         if (!path)
5120                 return -ENOMEM;
5121
5122         root = root->fs_info->extent_root;
5123
5124         last = max_t(u64, cache->key.objectid, BTRFS_SUPER_INFO_OFFSET);
5125
5126         key.objectid = last;
5127         key.offset = 0;
5128         key.type = BTRFS_EXTENT_ITEM_KEY;
5129
5130         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5131         if (ret < 0)
5132                 goto out;
5133         ret = 0;
5134         while (1) {
5135                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
5136                         ret = btrfs_next_leaf(root, path);
5137                         if (ret < 0)
5138                                 goto out;
5139                         if (ret > 0) {
5140                                 ret = 0;
5141                                 break;
5142                         }
5143                 }
5144                 leaf = path->nodes[0];
5145                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
5146                 if (key.objectid >= cache->key.offset + cache->key.objectid)
5147                         break;
5148                 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
5149                     key.type != BTRFS_METADATA_ITEM_KEY) {
5150                         path->slots[0]++;
5151                         continue;
5152                 }
5153
5154                 if (last == key.objectid) {
5155                         if (key.type == BTRFS_EXTENT_ITEM_KEY)
5156                                 last = key.objectid + key.offset;
5157                         else
5158                                 last = key.objectid + root->leafsize;
5159                         path->slots[0]++;
5160                         continue;
5161                 }
5162
5163                 ret = check_cache_range(root, cache, last,
5164                                         key.objectid - last);
5165                 if (ret)
5166                         break;
5167                 if (key.type == BTRFS_EXTENT_ITEM_KEY)
5168                         last = key.objectid + key.offset;
5169                 else
5170                         last = key.objectid + root->leafsize;
5171                 path->slots[0]++;
5172         }
5173
5174         if (last < cache->key.objectid + cache->key.offset)
5175                 ret = check_cache_range(root, cache, last,
5176                                         cache->key.objectid +
5177                                         cache->key.offset - last);
5178
5179 out:
5180         btrfs_free_path(path);
5181
5182         if (!ret &&
5183             !RB_EMPTY_ROOT(&cache->free_space_ctl->free_space_offset)) {
5184                 fprintf(stderr, "There are still entries left in the space "
5185                         "cache\n");
5186                 ret = -EINVAL;
5187         }
5188
5189         return ret;
5190 }
5191
5192 static int check_space_cache(struct btrfs_root *root)
5193 {
5194         struct btrfs_block_group_cache *cache;
5195         u64 start = BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE;
5196         int ret;
5197         int error = 0;
5198
5199         if (btrfs_super_cache_generation(root->fs_info->super_copy) != -1ULL &&
5200             btrfs_super_generation(root->fs_info->super_copy) !=
5201             btrfs_super_cache_generation(root->fs_info->super_copy)) {
5202                 printf("cache and super generation don't match, space cache "
5203                        "will be invalidated\n");
5204                 return 0;
5205         }
5206
5207         while (1) {
5208                 cache = btrfs_lookup_first_block_group(root->fs_info, start);
5209                 if (!cache)
5210                         break;
5211
5212                 start = cache->key.objectid + cache->key.offset;
5213                 if (!cache->free_space_ctl) {
5214                         if (btrfs_init_free_space_ctl(cache,
5215                                                       root->sectorsize)) {
5216                                 ret = -ENOMEM;
5217                                 break;
5218                         }
5219                 } else {
5220                         btrfs_remove_free_space_cache(cache);
5221                 }
5222
5223                 ret = load_free_space_cache(root->fs_info, cache);
5224                 if (!ret)
5225                         continue;
5226
5227                 ret = verify_space_cache(root, cache);
5228                 if (ret) {
5229                         fprintf(stderr, "cache appears valid but isnt %Lu\n",
5230                                 cache->key.objectid);
5231                         error++;
5232                 }
5233         }
5234
5235         return error ? -EINVAL : 0;
5236 }
5237
5238 static int read_extent_data(struct btrfs_root *root, char *data,
5239                         u64 logical, u64 *len, int mirror)
5240 {
5241         u64 offset = 0;
5242         struct btrfs_multi_bio *multi = NULL;
5243         struct btrfs_fs_info *info = root->fs_info;
5244         struct btrfs_device *device;
5245         int ret = 0;
5246         u64 max_len = *len;
5247
5248         ret = btrfs_map_block(&info->mapping_tree, READ, logical, len,
5249                               &multi, mirror, NULL);
5250         if (ret) {
5251                 fprintf(stderr, "Couldn't map the block %llu\n",
5252                                 logical + offset);
5253                 goto err;
5254         }
5255         device = multi->stripes[0].dev;
5256
5257         if (device->fd == 0)
5258                 goto err;
5259         if (*len > max_len)
5260                 *len = max_len;
5261
5262         ret = pread64(device->fd, data, *len, multi->stripes[0].physical);
5263         if (ret != *len)
5264                 ret = -EIO;
5265         else
5266                 ret = 0;
5267 err:
5268         kfree(multi);
5269         return ret;
5270 }
5271
5272 static int check_extent_csums(struct btrfs_root *root, u64 bytenr,
5273                         u64 num_bytes, unsigned long leaf_offset,
5274                         struct extent_buffer *eb) {
5275
5276         u64 offset = 0;
5277         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
5278         char *data;
5279         unsigned long csum_offset;
5280         u32 csum;
5281         u32 csum_expected;
5282         u64 read_len;
5283         u64 data_checked = 0;
5284         u64 tmp;
5285         int ret = 0;
5286         int mirror;
5287         int num_copies;
5288
5289         if (num_bytes % root->sectorsize)
5290                 return -EINVAL;
5291
5292         data = malloc(num_bytes);
5293         if (!data)
5294                 return -ENOMEM;
5295
5296         while (offset < num_bytes) {
5297                 mirror = 0;
5298 again:
5299                 read_len = num_bytes - offset;
5300                 /* read as much space once a time */
5301                 ret = read_extent_data(root, data + offset,
5302                                 bytenr + offset, &read_len, mirror);
5303                 if (ret)
5304                         goto out;
5305                 data_checked = 0;
5306                 /* verify every 4k data's checksum */
5307                 while (data_checked < read_len) {
5308                         csum = ~(u32)0;
5309                         tmp = offset + data_checked;
5310
5311                         csum = btrfs_csum_data(NULL, (char *)data + tmp,
5312                                                csum, root->sectorsize);
5313                         btrfs_csum_final(csum, (char *)&csum);
5314
5315                         csum_offset = leaf_offset +
5316                                  tmp / root->sectorsize * csum_size;
5317                         read_extent_buffer(eb, (char *)&csum_expected,
5318                                            csum_offset, csum_size);
5319                         /* try another mirror */
5320                         if (csum != csum_expected) {
5321                                 fprintf(stderr, "mirror %d bytenr %llu csum %u expected csum %u\n",
5322                                                 mirror, bytenr + tmp,
5323                                                 csum, csum_expected);
5324                                 num_copies = btrfs_num_copies(
5325                                                 &root->fs_info->mapping_tree,
5326                                                 bytenr, num_bytes);
5327                                 if (mirror < num_copies - 1) {
5328                                         mirror += 1;
5329                                         goto again;
5330                                 }
5331                         }
5332                         data_checked += root->sectorsize;
5333                 }
5334                 offset += read_len;
5335         }
5336 out:
5337         free(data);
5338         return ret;
5339 }
5340
5341 static int check_extent_exists(struct btrfs_root *root, u64 bytenr,
5342                                u64 num_bytes)
5343 {
5344         struct btrfs_path *path;
5345         struct extent_buffer *leaf;
5346         struct btrfs_key key;
5347         int ret;
5348
5349         path = btrfs_alloc_path();
5350         if (!path) {
5351                 fprintf(stderr, "Error allocing path\n");
5352                 return -ENOMEM;
5353         }
5354
5355         key.objectid = bytenr;
5356         key.type = BTRFS_EXTENT_ITEM_KEY;
5357         key.offset = (u64)-1;
5358
5359 again:
5360         ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
5361                                 0, 0);
5362         if (ret < 0) {
5363                 fprintf(stderr, "Error looking up extent record %d\n", ret);
5364                 btrfs_free_path(path);
5365                 return ret;
5366         } else if (ret) {
5367                 if (path->slots[0] > 0) {
5368                         path->slots[0]--;
5369                 } else {
5370                         ret = btrfs_prev_leaf(root, path);
5371                         if (ret < 0) {
5372                                 goto out;
5373                         } else if (ret > 0) {
5374                                 ret = 0;
5375                                 goto out;
5376                         }
5377                 }
5378         }
5379
5380         btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
5381
5382         /*
5383          * Block group items come before extent items if they have the same
5384          * bytenr, so walk back one more just in case.  Dear future traveler,
5385          * first congrats on mastering time travel.  Now if it's not too much
5386          * trouble could you go back to 2006 and tell Chris to make the
5387          * BLOCK_GROUP_ITEM_KEY (and BTRFS_*_REF_KEY) lower than the
5388          * EXTENT_ITEM_KEY please?
5389          */
5390         while (key.type > BTRFS_EXTENT_ITEM_KEY) {
5391                 if (path->slots[0] > 0) {
5392                         path->slots[0]--;
5393                 } else {
5394                         ret = btrfs_prev_leaf(root, path);
5395                         if (ret < 0) {
5396                                 goto out;
5397                         } else if (ret > 0) {
5398                                 ret = 0;
5399                                 goto out;
5400                         }
5401                 }
5402                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
5403         }
5404
5405         while (num_bytes) {
5406                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
5407                         ret = btrfs_next_leaf(root, path);
5408                         if (ret < 0) {
5409                                 fprintf(stderr, "Error going to next leaf "
5410                                         "%d\n", ret);
5411                                 btrfs_free_path(path);
5412                                 return ret;
5413                         } else if (ret) {
5414                                 break;
5415                         }
5416                 }
5417                 leaf = path->nodes[0];
5418                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
5419                 if (key.type != BTRFS_EXTENT_ITEM_KEY) {
5420                         path->slots[0]++;
5421                         continue;
5422                 }
5423                 if (key.objectid + key.offset < bytenr) {
5424                         path->slots[0]++;
5425                         continue;
5426                 }
5427                 if (key.objectid > bytenr + num_bytes)
5428                         break;
5429
5430                 if (key.objectid == bytenr) {
5431                         if (key.offset >= num_bytes) {
5432                                 num_bytes = 0;
5433                                 break;
5434                         }
5435                         num_bytes -= key.offset;
5436                         bytenr += key.offset;
5437                 } else if (key.objectid < bytenr) {
5438                         if (key.objectid + key.offset >= bytenr + num_bytes) {
5439                                 num_bytes = 0;
5440                                 break;
5441                         }
5442                         num_bytes = (bytenr + num_bytes) -
5443                                 (key.objectid + key.offset);
5444                         bytenr = key.objectid + key.offset;
5445                 } else {
5446                         if (key.objectid + key.offset < bytenr + num_bytes) {
5447                                 u64 new_start = key.objectid + key.offset;
5448                                 u64 new_bytes = bytenr + num_bytes - new_start;
5449
5450                                 /*
5451                                  * Weird case, the extent is in the middle of
5452                                  * our range, we'll have to search one side
5453                                  * and then the other.  Not sure if this happens
5454                                  * in real life, but no harm in coding it up
5455                                  * anyway just in case.
5456                                  */
5457                                 btrfs_release_path(path);
5458                                 ret = check_extent_exists(root, new_start,
5459                                                           new_bytes);
5460                                 if (ret) {
5461                                         fprintf(stderr, "Right section didn't "
5462                                                 "have a record\n");
5463                                         break;
5464                                 }
5465                                 num_bytes = key.objectid - bytenr;
5466                                 goto again;
5467                         }
5468                         num_bytes = key.objectid - bytenr;
5469                 }
5470                 path->slots[0]++;
5471         }
5472         ret = 0;
5473
5474 out:
5475         if (num_bytes && !ret) {
5476                 fprintf(stderr, "There are no extents for csum range "
5477                         "%Lu-%Lu\n", bytenr, bytenr+num_bytes);
5478                 ret = 1;
5479         }
5480
5481         btrfs_free_path(path);
5482         return ret;
5483 }
5484
5485 static int check_csums(struct btrfs_root *root)
5486 {
5487         struct btrfs_path *path;
5488         struct extent_buffer *leaf;
5489         struct btrfs_key key;
5490         u64 offset = 0, num_bytes = 0;
5491         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
5492         int errors = 0;
5493         int ret;
5494         u64 data_len;
5495         unsigned long leaf_offset;
5496
5497         root = root->fs_info->csum_root;
5498         if (!extent_buffer_uptodate(root->node)) {
5499                 fprintf(stderr, "No valid csum tree found\n");
5500                 return -ENOENT;
5501         }
5502
5503         key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
5504         key.type = BTRFS_EXTENT_CSUM_KEY;
5505         key.offset = 0;
5506
5507         path = btrfs_alloc_path();
5508         if (!path)
5509                 return -ENOMEM;
5510
5511         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5512         if (ret < 0) {
5513                 fprintf(stderr, "Error searching csum tree %d\n", ret);
5514                 btrfs_free_path(path);
5515                 return ret;
5516         }
5517
5518         if (ret > 0 && path->slots[0])
5519                 path->slots[0]--;
5520         ret = 0;
5521
5522         while (1) {
5523                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
5524                         ret = btrfs_next_leaf(root, path);
5525                         if (ret < 0) {
5526                                 fprintf(stderr, "Error going to next leaf "
5527                                         "%d\n", ret);
5528                                 break;
5529                         }
5530                         if (ret)
5531                                 break;
5532                 }
5533                 leaf = path->nodes[0];
5534
5535                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
5536                 if (key.type != BTRFS_EXTENT_CSUM_KEY) {
5537                         path->slots[0]++;
5538                         continue;
5539                 }
5540
5541                 data_len = (btrfs_item_size_nr(leaf, path->slots[0]) /
5542                               csum_size) * root->sectorsize;
5543                 if (!check_data_csum)
5544                         goto skip_csum_check;
5545                 leaf_offset = btrfs_item_ptr_offset(leaf, path->slots[0]);
5546                 ret = check_extent_csums(root, key.offset, data_len,
5547                                          leaf_offset, leaf);
5548                 if (ret)
5549                         break;
5550 skip_csum_check:
5551                 if (!num_bytes) {
5552                         offset = key.offset;
5553                 } else if (key.offset != offset + num_bytes) {
5554                         ret = check_extent_exists(root, offset, num_bytes);
5555                         if (ret) {
5556                                 fprintf(stderr, "Csum exists for %Lu-%Lu but "
5557                                         "there is no extent record\n",
5558                                         offset, offset+num_bytes);
5559                                 errors++;
5560                         }
5561                         offset = key.offset;
5562                         num_bytes = 0;
5563                 }
5564                 num_bytes += data_len;
5565                 path->slots[0]++;
5566         }
5567
5568         btrfs_free_path(path);
5569         return errors;
5570 }
5571
5572 static int is_dropped_key(struct btrfs_key *key,
5573                           struct btrfs_key *drop_key) {
5574         if (key->objectid < drop_key->objectid)
5575                 return 1;
5576         else if (key->objectid == drop_key->objectid) {
5577                 if (key->type < drop_key->type)
5578                         return 1;
5579                 else if (key->type == drop_key->type) {
5580                         if (key->offset < drop_key->offset)
5581                                 return 1;
5582                 }
5583         }
5584         return 0;
5585 }
5586
5587 /*
5588  * Here are the rules for FULL_BACKREF.
5589  *
5590  * 1) If BTRFS_HEADER_FLAG_RELOC is set then we have FULL_BACKREF set.
5591  * 2) If btrfs_header_owner(buf) no longer points to buf then we have
5592  *      FULL_BACKREF set.
5593  * 3) We cow'ed the block walking down a reloc tree.  This is impossible to tell
5594  *    if it happened after the relocation occurred since we'll have dropped the
5595  *    reloc root, so it's entirely possible to have FULL_BACKREF set on buf and
5596  *    have no real way to know for sure.
5597  *
5598  * We process the blocks one root at a time, and we start from the lowest root
5599  * objectid and go to the highest.  So we can just lookup the owner backref for
5600  * the record and if we don't find it then we know it doesn't exist and we have
5601  * a FULL BACKREF.
5602  *
5603  * FIXME: if we ever start reclaiming root objectid's then we need to fix this
5604  * assumption and simply indicate that we _think_ that the FULL BACKREF needs to
5605  * be set or not and then we can check later once we've gathered all the refs.
5606  */
5607 static int calc_extent_flag(struct btrfs_root *root,
5608                            struct cache_tree *extent_cache,
5609                            struct extent_buffer *buf,
5610                            struct root_item_record *ri,
5611                            u64 *flags)
5612 {
5613         struct extent_record *rec;
5614         struct cache_extent *cache;
5615         struct tree_backref *tback;
5616         u64 owner = 0;
5617
5618         cache = lookup_cache_extent(extent_cache, buf->start, 1);
5619         /* we have added this extent before */
5620         BUG_ON(!cache);
5621         rec = container_of(cache, struct extent_record, cache);
5622
5623         /*
5624          * Except file/reloc tree, we can not have
5625          * FULL BACKREF MODE
5626          */
5627         if (ri->objectid < BTRFS_FIRST_FREE_OBJECTID)
5628                 goto normal;
5629         /*
5630          * root node
5631          */
5632         if (buf->start == ri->bytenr)
5633                 goto normal;
5634
5635         if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))
5636                 goto full_backref;
5637
5638         owner = btrfs_header_owner(buf);
5639         if (owner == ri->objectid)
5640                 goto normal;
5641
5642         tback = find_tree_backref(rec, 0, owner);
5643         if (!tback)
5644                 goto full_backref;
5645 normal:
5646         *flags = 0;
5647         if (rec->flag_block_full_backref != -1 &&
5648             rec->flag_block_full_backref != 0)
5649                 rec->bad_full_backref = 1;
5650         return 0;
5651 full_backref:
5652         *flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5653         if (rec->flag_block_full_backref != -1 &&
5654             rec->flag_block_full_backref != 1)
5655                 rec->bad_full_backref = 1;
5656         return 0;
5657 }
5658
5659 static int run_next_block(struct btrfs_root *root,
5660                           struct block_info *bits,
5661                           int bits_nr,
5662                           u64 *last,
5663                           struct cache_tree *pending,
5664                           struct cache_tree *seen,
5665                           struct cache_tree *reada,
5666                           struct cache_tree *nodes,
5667                           struct cache_tree *extent_cache,
5668                           struct cache_tree *chunk_cache,
5669                           struct rb_root *dev_cache,
5670                           struct block_group_tree *block_group_cache,
5671                           struct device_extent_tree *dev_extent_cache,
5672                           struct root_item_record *ri)
5673 {
5674         struct extent_buffer *buf;
5675         struct extent_record *rec = NULL;
5676         u64 bytenr;
5677         u32 size;
5678         u64 parent;
5679         u64 owner;
5680         u64 flags;
5681         u64 ptr;
5682         u64 gen = 0;
5683         int ret = 0;
5684         int i;
5685         int nritems;
5686         struct btrfs_key key;
5687         struct cache_extent *cache;
5688         int reada_bits;
5689
5690         nritems = pick_next_pending(pending, reada, nodes, *last, bits,
5691                                     bits_nr, &reada_bits);
5692         if (nritems == 0)
5693                 return 1;
5694
5695         if (!reada_bits) {
5696                 for(i = 0; i < nritems; i++) {
5697                         ret = add_cache_extent(reada, bits[i].start,
5698                                                bits[i].size);
5699                         if (ret == -EEXIST)
5700                                 continue;
5701
5702                         /* fixme, get the parent transid */
5703                         readahead_tree_block(root, bits[i].start,
5704                                              bits[i].size, 0);
5705                 }
5706         }
5707         *last = bits[0].start;
5708         bytenr = bits[0].start;
5709         size = bits[0].size;
5710
5711         cache = lookup_cache_extent(pending, bytenr, size);
5712         if (cache) {
5713                 remove_cache_extent(pending, cache);
5714                 free(cache);
5715         }
5716         cache = lookup_cache_extent(reada, bytenr, size);
5717         if (cache) {
5718                 remove_cache_extent(reada, cache);
5719                 free(cache);
5720         }
5721         cache = lookup_cache_extent(nodes, bytenr, size);
5722         if (cache) {
5723                 remove_cache_extent(nodes, cache);
5724                 free(cache);
5725         }
5726         cache = lookup_cache_extent(extent_cache, bytenr, size);
5727         if (cache) {
5728                 rec = container_of(cache, struct extent_record, cache);
5729                 gen = rec->parent_generation;
5730         }
5731
5732         /* fixme, get the real parent transid */
5733         buf = read_tree_block(root, bytenr, size, gen);
5734         if (!extent_buffer_uptodate(buf)) {
5735                 record_bad_block_io(root->fs_info,
5736                                     extent_cache, bytenr, size);
5737                 goto out;
5738         }
5739
5740         nritems = btrfs_header_nritems(buf);
5741
5742         flags = 0;
5743         if (!init_extent_tree) {
5744                 ret = btrfs_lookup_extent_info(NULL, root, bytenr,
5745                                        btrfs_header_level(buf), 1, NULL,
5746                                        &flags);
5747                 if (ret < 0) {
5748                         ret = calc_extent_flag(root, extent_cache, buf, ri, &flags);
5749                         if (ret < 0) {
5750                                 fprintf(stderr, "Couldn't calc extent flags\n");
5751                                 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5752                         }
5753                 }
5754         } else {
5755                 flags = 0;
5756                 ret = calc_extent_flag(root, extent_cache, buf, ri, &flags);
5757                 if (ret < 0) {
5758                         fprintf(stderr, "Couldn't calc extent flags\n");
5759                         flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5760                 }
5761         }
5762
5763         if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
5764                 if (ri != NULL &&
5765                     ri->objectid != BTRFS_TREE_RELOC_OBJECTID &&
5766                     ri->objectid == btrfs_header_owner(buf)) {
5767                         /*
5768                          * Ok we got to this block from it's original owner and
5769                          * we have FULL_BACKREF set.  Relocation can leave
5770                          * converted blocks over so this is altogether possible,
5771                          * however it's not possible if the generation > the
5772                          * last snapshot, so check for this case.
5773                          */
5774                         if (!btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC) &&
5775                             btrfs_header_generation(buf) > ri->last_snapshot) {
5776                                 flags &= ~BTRFS_BLOCK_FLAG_FULL_BACKREF;
5777                                 rec->bad_full_backref = 1;
5778                         }
5779                 }
5780         } else {
5781                 if (ri != NULL &&
5782                     (ri->objectid == BTRFS_TREE_RELOC_OBJECTID ||
5783                      btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))) {
5784                         flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5785                         rec->bad_full_backref = 1;
5786                 }
5787         }
5788
5789         if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
5790                 rec->flag_block_full_backref = 1;
5791                 parent = bytenr;
5792                 owner = 0;
5793         } else {
5794                 rec->flag_block_full_backref = 0;
5795                 parent = 0;
5796                 owner = btrfs_header_owner(buf);
5797         }
5798
5799         ret = check_block(root, extent_cache, buf, flags);
5800         if (ret)
5801                 goto out;
5802
5803         if (btrfs_is_leaf(buf)) {
5804                 btree_space_waste += btrfs_leaf_free_space(root, buf);
5805                 for (i = 0; i < nritems; i++) {
5806                         struct btrfs_file_extent_item *fi;
5807                         btrfs_item_key_to_cpu(buf, &key, i);
5808                         if (key.type == BTRFS_EXTENT_ITEM_KEY) {
5809                                 process_extent_item(root, extent_cache, buf,
5810                                                     i);
5811                                 continue;
5812                         }
5813                         if (key.type == BTRFS_METADATA_ITEM_KEY) {
5814                                 process_extent_item(root, extent_cache, buf,
5815                                                     i);
5816                                 continue;
5817                         }
5818                         if (key.type == BTRFS_EXTENT_CSUM_KEY) {
5819                                 total_csum_bytes +=
5820                                         btrfs_item_size_nr(buf, i);
5821                                 continue;
5822                         }
5823                         if (key.type == BTRFS_CHUNK_ITEM_KEY) {
5824                                 process_chunk_item(chunk_cache, &key, buf, i);
5825                                 continue;
5826                         }
5827                         if (key.type == BTRFS_DEV_ITEM_KEY) {
5828                                 process_device_item(dev_cache, &key, buf, i);
5829                                 continue;
5830                         }
5831                         if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
5832                                 process_block_group_item(block_group_cache,
5833                                         &key, buf, i);
5834                                 continue;
5835                         }
5836                         if (key.type == BTRFS_DEV_EXTENT_KEY) {
5837                                 process_device_extent_item(dev_extent_cache,
5838                                         &key, buf, i);
5839                                 continue;
5840
5841                         }
5842                         if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
5843 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
5844                                 process_extent_ref_v0(extent_cache, buf, i);
5845 #else
5846                                 BUG();
5847 #endif
5848                                 continue;
5849                         }
5850
5851                         if (key.type == BTRFS_TREE_BLOCK_REF_KEY) {
5852                                 add_tree_backref(extent_cache, key.objectid, 0,
5853                                                  key.offset, 0);
5854                                 continue;
5855                         }
5856                         if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) {
5857                                 add_tree_backref(extent_cache, key.objectid,
5858                                                  key.offset, 0, 0);
5859                                 continue;
5860                         }
5861                         if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
5862                                 struct btrfs_extent_data_ref *ref;
5863                                 ref = btrfs_item_ptr(buf, i,
5864                                                 struct btrfs_extent_data_ref);
5865                                 add_data_backref(extent_cache,
5866                                         key.objectid, 0,
5867                                         btrfs_extent_data_ref_root(buf, ref),
5868                                         btrfs_extent_data_ref_objectid(buf,
5869                                                                        ref),
5870                                         btrfs_extent_data_ref_offset(buf, ref),
5871                                         btrfs_extent_data_ref_count(buf, ref),
5872                                         0, root->sectorsize);
5873                                 continue;
5874                         }
5875                         if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
5876                                 struct btrfs_shared_data_ref *ref;
5877                                 ref = btrfs_item_ptr(buf, i,
5878                                                 struct btrfs_shared_data_ref);
5879                                 add_data_backref(extent_cache,
5880                                         key.objectid, key.offset, 0, 0, 0,
5881                                         btrfs_shared_data_ref_count(buf, ref),
5882                                         0, root->sectorsize);
5883                                 continue;
5884                         }
5885                         if (key.type == BTRFS_ORPHAN_ITEM_KEY) {
5886                                 struct bad_item *bad;
5887
5888                                 if (key.objectid == BTRFS_ORPHAN_OBJECTID)
5889                                         continue;
5890                                 if (!owner)
5891                                         continue;
5892                                 bad = malloc(sizeof(struct bad_item));
5893                                 if (!bad)
5894                                         continue;
5895                                 INIT_LIST_HEAD(&bad->list);
5896                                 memcpy(&bad->key, &key,
5897                                        sizeof(struct btrfs_key));
5898                                 bad->root_id = owner;
5899                                 list_add_tail(&bad->list, &delete_items);
5900                                 continue;
5901                         }
5902                         if (key.type != BTRFS_EXTENT_DATA_KEY)
5903                                 continue;
5904                         fi = btrfs_item_ptr(buf, i,
5905                                             struct btrfs_file_extent_item);
5906                         if (btrfs_file_extent_type(buf, fi) ==
5907                             BTRFS_FILE_EXTENT_INLINE)
5908                                 continue;
5909                         if (btrfs_file_extent_disk_bytenr(buf, fi) == 0)
5910                                 continue;
5911
5912                         data_bytes_allocated +=
5913                                 btrfs_file_extent_disk_num_bytes(buf, fi);
5914                         if (data_bytes_allocated < root->sectorsize) {
5915                                 abort();
5916                         }
5917                         data_bytes_referenced +=
5918                                 btrfs_file_extent_num_bytes(buf, fi);
5919                         add_data_backref(extent_cache,
5920                                 btrfs_file_extent_disk_bytenr(buf, fi),
5921                                 parent, owner, key.objectid, key.offset -
5922                                 btrfs_file_extent_offset(buf, fi), 1, 1,
5923                                 btrfs_file_extent_disk_num_bytes(buf, fi));
5924                 }
5925         } else {
5926                 int level;
5927                 struct btrfs_key first_key;
5928
5929                 first_key.objectid = 0;
5930
5931                 if (nritems > 0)
5932                         btrfs_item_key_to_cpu(buf, &first_key, 0);
5933                 level = btrfs_header_level(buf);
5934                 for (i = 0; i < nritems; i++) {
5935                         ptr = btrfs_node_blockptr(buf, i);
5936                         size = btrfs_level_size(root, level - 1);
5937                         btrfs_node_key_to_cpu(buf, &key, i);
5938                         if (ri != NULL) {
5939                                 if ((level == ri->drop_level)
5940                                     && is_dropped_key(&key, &ri->drop_key)) {
5941                                         continue;
5942                                 }
5943                         }
5944                         ret = add_extent_rec(extent_cache, &key,
5945                                              btrfs_node_ptr_generation(buf, i),
5946                                              ptr, size, 0, 0, 1, 0, 1, 0,
5947                                              size);
5948                         BUG_ON(ret);
5949
5950                         add_tree_backref(extent_cache, ptr, parent, owner, 1);
5951
5952                         if (level > 1) {
5953                                 add_pending(nodes, seen, ptr, size);
5954                         } else {
5955                                 add_pending(pending, seen, ptr, size);
5956                         }
5957                 }
5958                 btree_space_waste += (BTRFS_NODEPTRS_PER_BLOCK(root) -
5959                                       nritems) * sizeof(struct btrfs_key_ptr);
5960         }
5961         total_btree_bytes += buf->len;
5962         if (fs_root_objectid(btrfs_header_owner(buf)))
5963                 total_fs_tree_bytes += buf->len;
5964         if (btrfs_header_owner(buf) == BTRFS_EXTENT_TREE_OBJECTID)
5965                 total_extent_tree_bytes += buf->len;
5966         if (!found_old_backref &&
5967             btrfs_header_owner(buf) == BTRFS_TREE_RELOC_OBJECTID &&
5968             btrfs_header_backref_rev(buf) == BTRFS_MIXED_BACKREF_REV &&
5969             !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))
5970                 found_old_backref = 1;
5971 out:
5972         free_extent_buffer(buf);
5973         return ret;
5974 }
5975
5976 static int add_root_to_pending(struct extent_buffer *buf,
5977                                struct cache_tree *extent_cache,
5978                                struct cache_tree *pending,
5979                                struct cache_tree *seen,
5980                                struct cache_tree *nodes,
5981                                u64 objectid)
5982 {
5983         if (btrfs_header_level(buf) > 0)
5984                 add_pending(nodes, seen, buf->start, buf->len);
5985         else
5986                 add_pending(pending, seen, buf->start, buf->len);
5987         add_extent_rec(extent_cache, NULL, 0, buf->start, buf->len,
5988                        0, 1, 1, 0, 1, 0, buf->len);
5989
5990         if (objectid == BTRFS_TREE_RELOC_OBJECTID ||
5991             btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV)
5992                 add_tree_backref(extent_cache, buf->start, buf->start,
5993                                  0, 1);
5994         else
5995                 add_tree_backref(extent_cache, buf->start, 0, objectid, 1);
5996         return 0;
5997 }
5998
5999 /* as we fix the tree, we might be deleting blocks that
6000  * we're tracking for repair.  This hook makes sure we
6001  * remove any backrefs for blocks as we are fixing them.
6002  */
6003 static int free_extent_hook(struct btrfs_trans_handle *trans,
6004                             struct btrfs_root *root,
6005                             u64 bytenr, u64 num_bytes, u64 parent,
6006                             u64 root_objectid, u64 owner, u64 offset,
6007                             int refs_to_drop)
6008 {
6009         struct extent_record *rec;
6010         struct cache_extent *cache;
6011         int is_data;
6012         struct cache_tree *extent_cache = root->fs_info->fsck_extent_cache;
6013
6014         is_data = owner >= BTRFS_FIRST_FREE_OBJECTID;
6015         cache = lookup_cache_extent(extent_cache, bytenr, num_bytes);
6016         if (!cache)
6017                 return 0;
6018
6019         rec = container_of(cache, struct extent_record, cache);
6020         if (is_data) {
6021                 struct data_backref *back;
6022                 back = find_data_backref(rec, parent, root_objectid, owner,
6023                                          offset, 1, bytenr, num_bytes);
6024                 if (!back)
6025                         goto out;
6026                 if (back->node.found_ref) {
6027                         back->found_ref -= refs_to_drop;
6028                         if (rec->refs)
6029                                 rec->refs -= refs_to_drop;
6030                 }
6031                 if (back->node.found_extent_tree) {
6032                         back->num_refs -= refs_to_drop;
6033                         if (rec->extent_item_refs)
6034                                 rec->extent_item_refs -= refs_to_drop;
6035                 }
6036                 if (back->found_ref == 0)
6037                         back->node.found_ref = 0;
6038                 if (back->num_refs == 0)
6039                         back->node.found_extent_tree = 0;
6040
6041                 if (!back->node.found_extent_tree && back->node.found_ref) {
6042                         list_del(&back->node.list);
6043                         free(back);
6044                 }
6045         } else {
6046                 struct tree_backref *back;
6047                 back = find_tree_backref(rec, parent, root_objectid);
6048                 if (!back)
6049                         goto out;
6050                 if (back->node.found_ref) {
6051                         if (rec->refs)
6052                                 rec->refs--;
6053                         back->node.found_ref = 0;
6054                 }
6055                 if (back->node.found_extent_tree) {
6056                         if (rec->extent_item_refs)
6057                                 rec->extent_item_refs--;
6058                         back->node.found_extent_tree = 0;
6059                 }
6060                 if (!back->node.found_extent_tree && back->node.found_ref) {
6061                         list_del(&back->node.list);
6062                         free(back);
6063                 }
6064         }
6065         maybe_free_extent_rec(extent_cache, rec);
6066 out:
6067         return 0;
6068 }
6069
6070 static int delete_extent_records(struct btrfs_trans_handle *trans,
6071                                  struct btrfs_root *root,
6072                                  struct btrfs_path *path,
6073                                  u64 bytenr, u64 new_len)
6074 {
6075         struct btrfs_key key;
6076         struct btrfs_key found_key;
6077         struct extent_buffer *leaf;
6078         int ret;
6079         int slot;
6080
6081
6082         key.objectid = bytenr;
6083         key.type = (u8)-1;
6084         key.offset = (u64)-1;
6085
6086         while(1) {
6087                 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
6088                                         &key, path, 0, 1);
6089                 if (ret < 0)
6090                         break;
6091
6092                 if (ret > 0) {
6093                         ret = 0;
6094                         if (path->slots[0] == 0)
6095                                 break;
6096                         path->slots[0]--;
6097                 }
6098                 ret = 0;
6099
6100                 leaf = path->nodes[0];
6101                 slot = path->slots[0];
6102
6103                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6104                 if (found_key.objectid != bytenr)
6105                         break;
6106
6107                 if (found_key.type != BTRFS_EXTENT_ITEM_KEY &&
6108                     found_key.type != BTRFS_METADATA_ITEM_KEY &&
6109                     found_key.type != BTRFS_TREE_BLOCK_REF_KEY &&
6110                     found_key.type != BTRFS_EXTENT_DATA_REF_KEY &&
6111                     found_key.type != BTRFS_EXTENT_REF_V0_KEY &&
6112                     found_key.type != BTRFS_SHARED_BLOCK_REF_KEY &&
6113                     found_key.type != BTRFS_SHARED_DATA_REF_KEY) {
6114                         btrfs_release_path(path);
6115                         if (found_key.type == 0) {
6116                                 if (found_key.offset == 0)
6117                                         break;
6118                                 key.offset = found_key.offset - 1;
6119                                 key.type = found_key.type;
6120                         }
6121                         key.type = found_key.type - 1;
6122                         key.offset = (u64)-1;
6123                         continue;
6124                 }
6125
6126                 fprintf(stderr, "repair deleting extent record: key %Lu %u %Lu\n",
6127                         found_key.objectid, found_key.type, found_key.offset);
6128
6129                 ret = btrfs_del_item(trans, root->fs_info->extent_root, path);
6130                 if (ret)
6131                         break;
6132                 btrfs_release_path(path);
6133
6134                 if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
6135                     found_key.type == BTRFS_METADATA_ITEM_KEY) {
6136                         u64 bytes = (found_key.type == BTRFS_EXTENT_ITEM_KEY) ?
6137                                 found_key.offset : root->leafsize;
6138
6139                         ret = btrfs_update_block_group(trans, root, bytenr,
6140                                                        bytes, 0, 0);
6141                         if (ret)
6142                                 break;
6143                 }
6144         }
6145
6146         btrfs_release_path(path);
6147         return ret;
6148 }
6149
6150 /*
6151  * for a single backref, this will allocate a new extent
6152  * and add the backref to it.
6153  */
6154 static int record_extent(struct btrfs_trans_handle *trans,
6155                          struct btrfs_fs_info *info,
6156                          struct btrfs_path *path,
6157                          struct extent_record *rec,
6158                          struct extent_backref *back,
6159                          int allocated, u64 flags)
6160 {
6161         int ret;
6162         struct btrfs_root *extent_root = info->extent_root;
6163         struct extent_buffer *leaf;
6164         struct btrfs_key ins_key;
6165         struct btrfs_extent_item *ei;
6166         struct tree_backref *tback;
6167         struct data_backref *dback;
6168         struct btrfs_tree_block_info *bi;
6169
6170         if (!back->is_data)
6171                 rec->max_size = max_t(u64, rec->max_size,
6172                                     info->extent_root->leafsize);
6173
6174         if (!allocated) {
6175                 u32 item_size = sizeof(*ei);
6176
6177                 if (!back->is_data)
6178                         item_size += sizeof(*bi);
6179
6180                 ins_key.objectid = rec->start;
6181                 ins_key.offset = rec->max_size;
6182                 ins_key.type = BTRFS_EXTENT_ITEM_KEY;
6183
6184                 ret = btrfs_insert_empty_item(trans, extent_root, path,
6185                                         &ins_key, item_size);
6186                 if (ret)
6187                         goto fail;
6188
6189                 leaf = path->nodes[0];
6190                 ei = btrfs_item_ptr(leaf, path->slots[0],
6191                                     struct btrfs_extent_item);
6192
6193                 btrfs_set_extent_refs(leaf, ei, 0);
6194                 btrfs_set_extent_generation(leaf, ei, rec->generation);
6195
6196                 if (back->is_data) {
6197                         btrfs_set_extent_flags(leaf, ei,
6198                                                BTRFS_EXTENT_FLAG_DATA);
6199                 } else {
6200                         struct btrfs_disk_key copy_key;;
6201
6202                         tback = (struct tree_backref *)back;
6203                         bi = (struct btrfs_tree_block_info *)(ei + 1);
6204                         memset_extent_buffer(leaf, 0, (unsigned long)bi,
6205                                              sizeof(*bi));
6206
6207                         btrfs_set_disk_key_objectid(&copy_key,
6208                                                     rec->info_objectid);
6209                         btrfs_set_disk_key_type(&copy_key, 0);
6210                         btrfs_set_disk_key_offset(&copy_key, 0);
6211
6212                         btrfs_set_tree_block_level(leaf, bi, rec->info_level);
6213                         btrfs_set_tree_block_key(leaf, bi, &copy_key);
6214
6215                         btrfs_set_extent_flags(leaf, ei,
6216                                                BTRFS_EXTENT_FLAG_TREE_BLOCK | flags);
6217                 }
6218
6219                 btrfs_mark_buffer_dirty(leaf);
6220                 ret = btrfs_update_block_group(trans, extent_root, rec->start,
6221                                                rec->max_size, 1, 0);
6222                 if (ret)
6223                         goto fail;
6224                 btrfs_release_path(path);
6225         }
6226
6227         if (back->is_data) {
6228                 u64 parent;
6229                 int i;
6230
6231                 dback = (struct data_backref *)back;
6232                 if (back->full_backref)
6233                         parent = dback->parent;
6234                 else
6235                         parent = 0;
6236
6237                 for (i = 0; i < dback->found_ref; i++) {
6238                         /* if parent != 0, we're doing a full backref
6239                          * passing BTRFS_FIRST_FREE_OBJECTID as the owner
6240                          * just makes the backref allocator create a data
6241                          * backref
6242                          */
6243                         ret = btrfs_inc_extent_ref(trans, info->extent_root,
6244                                                    rec->start, rec->max_size,
6245                                                    parent,
6246                                                    dback->root,
6247                                                    parent ?
6248                                                    BTRFS_FIRST_FREE_OBJECTID :
6249                                                    dback->owner,
6250                                                    dback->offset);
6251                         if (ret)
6252                                 break;
6253                 }
6254                 fprintf(stderr, "adding new data backref"
6255                                 " on %llu %s %llu owner %llu"
6256                                 " offset %llu found %d\n",
6257                                 (unsigned long long)rec->start,
6258                                 back->full_backref ?
6259                                 "parent" : "root",
6260                                 back->full_backref ?
6261                                 (unsigned long long)parent :
6262                                 (unsigned long long)dback->root,
6263                                 (unsigned long long)dback->owner,
6264                                 (unsigned long long)dback->offset,
6265                                 dback->found_ref);
6266         } else {
6267                 u64 parent;
6268
6269                 tback = (struct tree_backref *)back;
6270                 if (back->full_backref)
6271                         parent = tback->parent;
6272                 else
6273                         parent = 0;
6274
6275                 ret = btrfs_inc_extent_ref(trans, info->extent_root,
6276                                            rec->start, rec->max_size,
6277                                            parent, tback->root, 0, 0);
6278                 fprintf(stderr, "adding new tree backref on "
6279                         "start %llu len %llu parent %llu root %llu\n",
6280                         rec->start, rec->max_size, parent, tback->root);
6281         }
6282         if (ret)
6283                 goto fail;
6284 fail:
6285         btrfs_release_path(path);
6286         return ret;
6287 }
6288
6289 struct extent_entry {
6290         u64 bytenr;
6291         u64 bytes;
6292         int count;
6293         int broken;
6294         struct list_head list;
6295 };
6296
6297 static struct extent_entry *find_entry(struct list_head *entries,
6298                                        u64 bytenr, u64 bytes)
6299 {
6300         struct extent_entry *entry = NULL;
6301
6302         list_for_each_entry(entry, entries, list) {
6303                 if (entry->bytenr == bytenr && entry->bytes == bytes)
6304                         return entry;
6305         }
6306
6307         return NULL;
6308 }
6309
6310 static struct extent_entry *find_most_right_entry(struct list_head *entries)
6311 {
6312         struct extent_entry *entry, *best = NULL, *prev = NULL;
6313
6314         list_for_each_entry(entry, entries, list) {
6315                 if (!prev) {
6316                         prev = entry;
6317                         continue;
6318                 }
6319
6320                 /*
6321                  * If there are as many broken entries as entries then we know
6322                  * not to trust this particular entry.
6323                  */
6324                 if (entry->broken == entry->count)
6325                         continue;
6326
6327                 /*
6328                  * If our current entry == best then we can't be sure our best
6329                  * is really the best, so we need to keep searching.
6330                  */
6331                 if (best && best->count == entry->count) {
6332                         prev = entry;
6333                         best = NULL;
6334                         continue;
6335                 }
6336
6337                 /* Prev == entry, not good enough, have to keep searching */
6338                 if (!prev->broken && prev->count == entry->count)
6339                         continue;
6340
6341                 if (!best)
6342                         best = (prev->count > entry->count) ? prev : entry;
6343                 else if (best->count < entry->count)
6344                         best = entry;
6345                 prev = entry;
6346         }
6347
6348         return best;
6349 }
6350
6351 static int repair_ref(struct btrfs_fs_info *info, struct btrfs_path *path,
6352                       struct data_backref *dback, struct extent_entry *entry)
6353 {
6354         struct btrfs_trans_handle *trans;
6355         struct btrfs_root *root;
6356         struct btrfs_file_extent_item *fi;
6357         struct extent_buffer *leaf;
6358         struct btrfs_key key;
6359         u64 bytenr, bytes;
6360         int ret, err;
6361
6362         key.objectid = dback->root;
6363         key.type = BTRFS_ROOT_ITEM_KEY;
6364         key.offset = (u64)-1;
6365         root = btrfs_read_fs_root(info, &key);
6366         if (IS_ERR(root)) {
6367                 fprintf(stderr, "Couldn't find root for our ref\n");
6368                 return -EINVAL;
6369         }
6370
6371         /*
6372          * The backref points to the original offset of the extent if it was
6373          * split, so we need to search down to the offset we have and then walk
6374          * forward until we find the backref we're looking for.
6375          */
6376         key.objectid = dback->owner;
6377         key.type = BTRFS_EXTENT_DATA_KEY;
6378         key.offset = dback->offset;
6379         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6380         if (ret < 0) {
6381                 fprintf(stderr, "Error looking up ref %d\n", ret);
6382                 return ret;
6383         }
6384
6385         while (1) {
6386                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
6387                         ret = btrfs_next_leaf(root, path);
6388                         if (ret) {
6389                                 fprintf(stderr, "Couldn't find our ref, next\n");
6390                                 return -EINVAL;
6391                         }
6392                 }
6393                 leaf = path->nodes[0];
6394                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
6395                 if (key.objectid != dback->owner ||
6396                     key.type != BTRFS_EXTENT_DATA_KEY) {
6397                         fprintf(stderr, "Couldn't find our ref, search\n");
6398                         return -EINVAL;
6399                 }
6400                 fi = btrfs_item_ptr(leaf, path->slots[0],
6401                                     struct btrfs_file_extent_item);
6402                 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6403                 bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
6404
6405                 if (bytenr == dback->disk_bytenr && bytes == dback->bytes)
6406                         break;
6407                 path->slots[0]++;
6408         }
6409
6410         btrfs_release_path(path);
6411
6412         trans = btrfs_start_transaction(root, 1);
6413         if (IS_ERR(trans))
6414                 return PTR_ERR(trans);
6415
6416         /*
6417          * Ok we have the key of the file extent we want to fix, now we can cow
6418          * down to the thing and fix it.
6419          */
6420         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
6421         if (ret < 0) {
6422                 fprintf(stderr, "Error cowing down to ref [%Lu, %u, %Lu]: %d\n",
6423                         key.objectid, key.type, key.offset, ret);
6424                 goto out;
6425         }
6426         if (ret > 0) {
6427                 fprintf(stderr, "Well that's odd, we just found this key "
6428                         "[%Lu, %u, %Lu]\n", key.objectid, key.type,
6429                         key.offset);
6430                 ret = -EINVAL;
6431                 goto out;
6432         }
6433         leaf = path->nodes[0];
6434         fi = btrfs_item_ptr(leaf, path->slots[0],
6435                             struct btrfs_file_extent_item);
6436
6437         if (btrfs_file_extent_compression(leaf, fi) &&
6438             dback->disk_bytenr != entry->bytenr) {
6439                 fprintf(stderr, "Ref doesn't match the record start and is "
6440                         "compressed, please take a btrfs-image of this file "
6441                         "system and send it to a btrfs developer so they can "
6442                         "complete this functionality for bytenr %Lu\n",
6443                         dback->disk_bytenr);
6444                 ret = -EINVAL;
6445                 goto out;
6446         }
6447
6448         if (dback->node.broken && dback->disk_bytenr != entry->bytenr) {
6449                 btrfs_set_file_extent_disk_bytenr(leaf, fi, entry->bytenr);
6450         } else if (dback->disk_bytenr > entry->bytenr) {
6451                 u64 off_diff, offset;
6452
6453                 off_diff = dback->disk_bytenr - entry->bytenr;
6454                 offset = btrfs_file_extent_offset(leaf, fi);
6455                 if (dback->disk_bytenr + offset +
6456                     btrfs_file_extent_num_bytes(leaf, fi) >
6457                     entry->bytenr + entry->bytes) {
6458                         fprintf(stderr, "Ref is past the entry end, please "
6459                                 "take a btrfs-image of this file system and "
6460                                 "send it to a btrfs developer, ref %Lu\n",
6461                                 dback->disk_bytenr);
6462                         ret = -EINVAL;
6463                         goto out;
6464                 }
6465                 offset += off_diff;
6466                 btrfs_set_file_extent_disk_bytenr(leaf, fi, entry->bytenr);
6467                 btrfs_set_file_extent_offset(leaf, fi, offset);
6468         } else if (dback->disk_bytenr < entry->bytenr) {
6469                 u64 offset;
6470
6471                 offset = btrfs_file_extent_offset(leaf, fi);
6472                 if (dback->disk_bytenr + offset < entry->bytenr) {
6473                         fprintf(stderr, "Ref is before the entry start, please"
6474                                 " take a btrfs-image of this file system and "
6475                                 "send it to a btrfs developer, ref %Lu\n",
6476                                 dback->disk_bytenr);
6477                         ret = -EINVAL;
6478                         goto out;
6479                 }
6480
6481                 offset += dback->disk_bytenr;
6482                 offset -= entry->bytenr;
6483                 btrfs_set_file_extent_disk_bytenr(leaf, fi, entry->bytenr);
6484                 btrfs_set_file_extent_offset(leaf, fi, offset);
6485         }
6486
6487         btrfs_set_file_extent_disk_num_bytes(leaf, fi, entry->bytes);
6488
6489         /*
6490          * Chances are if disk_num_bytes were wrong then so is ram_bytes, but
6491          * only do this if we aren't using compression, otherwise it's a
6492          * trickier case.
6493          */
6494         if (!btrfs_file_extent_compression(leaf, fi))
6495                 btrfs_set_file_extent_ram_bytes(leaf, fi, entry->bytes);
6496         else
6497                 printf("ram bytes may be wrong?\n");
6498         btrfs_mark_buffer_dirty(leaf);
6499 out:
6500         err = btrfs_commit_transaction(trans, root);
6501         btrfs_release_path(path);
6502         return ret ? ret : err;
6503 }
6504
6505 static int verify_backrefs(struct btrfs_fs_info *info, struct btrfs_path *path,
6506                            struct extent_record *rec)
6507 {
6508         struct extent_backref *back;
6509         struct data_backref *dback;
6510         struct extent_entry *entry, *best = NULL;
6511         LIST_HEAD(entries);
6512         int nr_entries = 0;
6513         int broken_entries = 0;
6514         int ret = 0;
6515         short mismatch = 0;
6516
6517         /*
6518          * Metadata is easy and the backrefs should always agree on bytenr and
6519          * size, if not we've got bigger issues.
6520          */
6521         if (rec->metadata)
6522                 return 0;
6523
6524         list_for_each_entry(back, &rec->backrefs, list) {
6525                 if (back->full_backref || !back->is_data)
6526                         continue;
6527
6528                 dback = (struct data_backref *)back;
6529
6530                 /*
6531                  * We only pay attention to backrefs that we found a real
6532                  * backref for.
6533                  */
6534                 if (dback->found_ref == 0)
6535                         continue;
6536
6537                 /*
6538                  * For now we only catch when the bytes don't match, not the
6539                  * bytenr.  We can easily do this at the same time, but I want
6540                  * to have a fs image to test on before we just add repair
6541                  * functionality willy-nilly so we know we won't screw up the
6542                  * repair.
6543                  */
6544
6545                 entry = find_entry(&entries, dback->disk_bytenr,
6546                                    dback->bytes);
6547                 if (!entry) {
6548                         entry = malloc(sizeof(struct extent_entry));
6549                         if (!entry) {
6550                                 ret = -ENOMEM;
6551                                 goto out;
6552                         }
6553                         memset(entry, 0, sizeof(*entry));
6554                         entry->bytenr = dback->disk_bytenr;
6555                         entry->bytes = dback->bytes;
6556                         list_add_tail(&entry->list, &entries);
6557                         nr_entries++;
6558                 }
6559
6560                 /*
6561                  * If we only have on entry we may think the entries agree when
6562                  * in reality they don't so we have to do some extra checking.
6563                  */
6564                 if (dback->disk_bytenr != rec->start ||
6565                     dback->bytes != rec->nr || back->broken)
6566                         mismatch = 1;
6567
6568                 if (back->broken) {
6569                         entry->broken++;
6570                         broken_entries++;
6571                 }
6572
6573                 entry->count++;
6574         }
6575
6576         /* Yay all the backrefs agree, carry on good sir */
6577         if (nr_entries <= 1 && !mismatch)
6578                 goto out;
6579
6580         fprintf(stderr, "attempting to repair backref discrepency for bytenr "
6581                 "%Lu\n", rec->start);
6582
6583         /*
6584          * First we want to see if the backrefs can agree amongst themselves who
6585          * is right, so figure out which one of the entries has the highest
6586          * count.
6587          */
6588         best = find_most_right_entry(&entries);
6589
6590         /*
6591          * Ok so we may have an even split between what the backrefs think, so
6592          * this is where we use the extent ref to see what it thinks.
6593          */
6594         if (!best) {
6595                 entry = find_entry(&entries, rec->start, rec->nr);
6596                 if (!entry && (!broken_entries || !rec->found_rec)) {
6597                         fprintf(stderr, "Backrefs don't agree with each other "
6598                                 "and extent record doesn't agree with anybody,"
6599                                 " so we can't fix bytenr %Lu bytes %Lu\n",
6600                                 rec->start, rec->nr);
6601                         ret = -EINVAL;
6602                         goto out;
6603                 } else if (!entry) {
6604                         /*
6605                          * Ok our backrefs were broken, we'll assume this is the
6606                          * correct value and add an entry for this range.
6607                          */
6608                         entry = malloc(sizeof(struct extent_entry));
6609                         if (!entry) {
6610                                 ret = -ENOMEM;
6611                                 goto out;
6612                         }
6613                         memset(entry, 0, sizeof(*entry));
6614                         entry->bytenr = rec->start;
6615                         entry->bytes = rec->nr;
6616                         list_add_tail(&entry->list, &entries);
6617                         nr_entries++;
6618                 }
6619                 entry->count++;
6620                 best = find_most_right_entry(&entries);
6621                 if (!best) {
6622                         fprintf(stderr, "Backrefs and extent record evenly "
6623                                 "split on who is right, this is going to "
6624                                 "require user input to fix bytenr %Lu bytes "
6625                                 "%Lu\n", rec->start, rec->nr);
6626                         ret = -EINVAL;
6627                         goto out;
6628                 }
6629         }
6630
6631         /*
6632          * I don't think this can happen currently as we'll abort() if we catch
6633          * this case higher up, but in case somebody removes that we still can't
6634          * deal with it properly here yet, so just bail out of that's the case.
6635          */
6636         if (best->bytenr != rec->start) {
6637                 fprintf(stderr, "Extent start and backref starts don't match, "
6638                         "please use btrfs-image on this file system and send "
6639                         "it to a btrfs developer so they can make fsck fix "
6640                         "this particular case.  bytenr is %Lu, bytes is %Lu\n",
6641                         rec->start, rec->nr);
6642                 ret = -EINVAL;
6643                 goto out;
6644         }
6645
6646         /*
6647          * Ok great we all agreed on an extent record, let's go find the real
6648          * references and fix up the ones that don't match.
6649          */
6650         list_for_each_entry(back, &rec->backrefs, list) {
6651                 if (back->full_backref || !back->is_data)
6652                         continue;
6653
6654                 dback = (struct data_backref *)back;
6655
6656                 /*
6657                  * Still ignoring backrefs that don't have a real ref attached
6658                  * to them.
6659                  */
6660                 if (dback->found_ref == 0)
6661                         continue;
6662
6663                 if (dback->bytes == best->bytes &&
6664                     dback->disk_bytenr == best->bytenr)
6665                         continue;
6666
6667                 ret = repair_ref(info, path, dback, best);
6668                 if (ret)
6669                         goto out;
6670         }
6671
6672         /*
6673          * Ok we messed with the actual refs, which means we need to drop our
6674          * entire cache and go back and rescan.  I know this is a huge pain and
6675          * adds a lot of extra work, but it's the only way to be safe.  Once all
6676          * the backrefs agree we may not need to do anything to the extent
6677          * record itself.
6678          */
6679         ret = -EAGAIN;
6680 out:
6681         while (!list_empty(&entries)) {
6682                 entry = list_entry(entries.next, struct extent_entry, list);
6683                 list_del_init(&entry->list);
6684                 free(entry);
6685         }
6686         return ret;
6687 }
6688
6689 static int process_duplicates(struct btrfs_root *root,
6690                               struct cache_tree *extent_cache,
6691                               struct extent_record *rec)
6692 {
6693         struct extent_record *good, *tmp;
6694         struct cache_extent *cache;
6695         int ret;
6696
6697         /*
6698          * If we found a extent record for this extent then return, or if we
6699          * have more than one duplicate we are likely going to need to delete
6700          * something.
6701          */
6702         if (rec->found_rec || rec->num_duplicates > 1)
6703                 return 0;
6704
6705         /* Shouldn't happen but just in case */
6706         BUG_ON(!rec->num_duplicates);
6707
6708         /*
6709          * So this happens if we end up with a backref that doesn't match the
6710          * actual extent entry.  So either the backref is bad or the extent
6711          * entry is bad.  Either way we want to have the extent_record actually
6712          * reflect what we found in the extent_tree, so we need to take the
6713          * duplicate out and use that as the extent_record since the only way we
6714          * get a duplicate is if we find a real life BTRFS_EXTENT_ITEM_KEY.
6715          */
6716         remove_cache_extent(extent_cache, &rec->cache);
6717
6718         good = list_entry(rec->dups.next, struct extent_record, list);
6719         list_del_init(&good->list);
6720         INIT_LIST_HEAD(&good->backrefs);
6721         INIT_LIST_HEAD(&good->dups);
6722         good->cache.start = good->start;
6723         good->cache.size = good->nr;
6724         good->content_checked = 0;
6725         good->owner_ref_checked = 0;
6726         good->num_duplicates = 0;
6727         good->refs = rec->refs;
6728         list_splice_init(&rec->backrefs, &good->backrefs);
6729         while (1) {
6730                 cache = lookup_cache_extent(extent_cache, good->start,
6731                                             good->nr);
6732                 if (!cache)
6733                         break;
6734                 tmp = container_of(cache, struct extent_record, cache);
6735
6736                 /*
6737                  * If we find another overlapping extent and it's found_rec is
6738                  * set then it's a duplicate and we need to try and delete
6739                  * something.
6740                  */
6741                 if (tmp->found_rec || tmp->num_duplicates > 0) {
6742                         if (list_empty(&good->list))
6743                                 list_add_tail(&good->list,
6744                                               &duplicate_extents);
6745                         good->num_duplicates += tmp->num_duplicates + 1;
6746                         list_splice_init(&tmp->dups, &good->dups);
6747                         list_del_init(&tmp->list);
6748                         list_add_tail(&tmp->list, &good->dups);
6749                         remove_cache_extent(extent_cache, &tmp->cache);
6750                         continue;
6751                 }
6752
6753                 /*
6754                  * Ok we have another non extent item backed extent rec, so lets
6755                  * just add it to this extent and carry on like we did above.
6756                  */
6757                 good->refs += tmp->refs;
6758                 list_splice_init(&tmp->backrefs, &good->backrefs);
6759                 remove_cache_extent(extent_cache, &tmp->cache);
6760                 free(tmp);
6761         }
6762         ret = insert_cache_extent(extent_cache, &good->cache);
6763         BUG_ON(ret);
6764         free(rec);
6765         return good->num_duplicates ? 0 : 1;
6766 }
6767
6768 static int delete_duplicate_records(struct btrfs_root *root,
6769                                     struct extent_record *rec)
6770 {
6771         struct btrfs_trans_handle *trans;
6772         LIST_HEAD(delete_list);
6773         struct btrfs_path *path;
6774         struct extent_record *tmp, *good, *n;
6775         int nr_del = 0;
6776         int ret = 0, err;
6777         struct btrfs_key key;
6778
6779         path = btrfs_alloc_path();
6780         if (!path) {
6781                 ret = -ENOMEM;
6782                 goto out;
6783         }
6784
6785         good = rec;
6786         /* Find the record that covers all of the duplicates. */
6787         list_for_each_entry(tmp, &rec->dups, list) {
6788                 if (good->start < tmp->start)
6789                         continue;
6790                 if (good->nr > tmp->nr)
6791                         continue;
6792
6793                 if (tmp->start + tmp->nr < good->start + good->nr) {
6794                         fprintf(stderr, "Ok we have overlapping extents that "
6795                                 "aren't completely covered by eachother, this "
6796                                 "is going to require more careful thought.  "
6797                                 "The extents are [%Lu-%Lu] and [%Lu-%Lu]\n",
6798                                 tmp->start, tmp->nr, good->start, good->nr);
6799                         abort();
6800                 }
6801                 good = tmp;
6802         }
6803
6804         if (good != rec)
6805                 list_add_tail(&rec->list, &delete_list);
6806
6807         list_for_each_entry_safe(tmp, n, &rec->dups, list) {
6808                 if (tmp == good)
6809                         continue;
6810                 list_move_tail(&tmp->list, &delete_list);
6811         }
6812
6813         root = root->fs_info->extent_root;
6814         trans = btrfs_start_transaction(root, 1);
6815         if (IS_ERR(trans)) {
6816                 ret = PTR_ERR(trans);
6817                 goto out;
6818         }
6819
6820         list_for_each_entry(tmp, &delete_list, list) {
6821                 if (tmp->found_rec == 0)
6822                         continue;
6823                 key.objectid = tmp->start;
6824                 key.type = BTRFS_EXTENT_ITEM_KEY;
6825                 key.offset = tmp->nr;
6826
6827                 /* Shouldn't happen but just in case */
6828                 if (tmp->metadata) {
6829                         fprintf(stderr, "Well this shouldn't happen, extent "
6830                                 "record overlaps but is metadata? "
6831                                 "[%Lu, %Lu]\n", tmp->start, tmp->nr);
6832                         abort();
6833                 }
6834
6835                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
6836                 if (ret) {
6837                         if (ret > 0)
6838                                 ret = -EINVAL;
6839                         break;
6840                 }
6841                 ret = btrfs_del_item(trans, root, path);
6842                 if (ret)
6843                         break;
6844                 btrfs_release_path(path);
6845                 nr_del++;
6846         }
6847         err = btrfs_commit_transaction(trans, root);
6848         if (err && !ret)
6849                 ret = err;
6850 out:
6851         while (!list_empty(&delete_list)) {
6852                 tmp = list_entry(delete_list.next, struct extent_record, list);
6853                 list_del_init(&tmp->list);
6854                 if (tmp == rec)
6855                         continue;
6856                 free(tmp);
6857         }
6858
6859         while (!list_empty(&rec->dups)) {
6860                 tmp = list_entry(rec->dups.next, struct extent_record, list);
6861                 list_del_init(&tmp->list);
6862                 free(tmp);
6863         }
6864
6865         btrfs_free_path(path);
6866
6867         if (!ret && !nr_del)
6868                 rec->num_duplicates = 0;
6869
6870         return ret ? ret : nr_del;
6871 }
6872
6873 static int find_possible_backrefs(struct btrfs_fs_info *info,
6874                                   struct btrfs_path *path,
6875                                   struct cache_tree *extent_cache,
6876                                   struct extent_record *rec)
6877 {
6878         struct btrfs_root *root;
6879         struct extent_backref *back;
6880         struct data_backref *dback;
6881         struct cache_extent *cache;
6882         struct btrfs_file_extent_item *fi;
6883         struct btrfs_key key;
6884         u64 bytenr, bytes;
6885         int ret;
6886
6887         list_for_each_entry(back, &rec->backrefs, list) {
6888                 /* Don't care about full backrefs (poor unloved backrefs) */
6889                 if (back->full_backref || !back->is_data)
6890                         continue;
6891
6892                 dback = (struct data_backref *)back;
6893
6894                 /* We found this one, we don't need to do a lookup */
6895                 if (dback->found_ref)
6896                         continue;
6897
6898                 key.objectid = dback->root;
6899                 key.type = BTRFS_ROOT_ITEM_KEY;
6900                 key.offset = (u64)-1;
6901
6902                 root = btrfs_read_fs_root(info, &key);
6903
6904                 /* No root, definitely a bad ref, skip */
6905                 if (IS_ERR(root) && PTR_ERR(root) == -ENOENT)
6906                         continue;
6907                 /* Other err, exit */
6908                 if (IS_ERR(root))
6909                         return PTR_ERR(root);
6910
6911                 key.objectid = dback->owner;
6912                 key.type = BTRFS_EXTENT_DATA_KEY;
6913                 key.offset = dback->offset;
6914                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6915                 if (ret) {
6916                         btrfs_release_path(path);
6917                         if (ret < 0)
6918                                 return ret;
6919                         /* Didn't find it, we can carry on */
6920                         ret = 0;
6921                         continue;
6922                 }
6923
6924                 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
6925                                     struct btrfs_file_extent_item);
6926                 bytenr = btrfs_file_extent_disk_bytenr(path->nodes[0], fi);
6927                 bytes = btrfs_file_extent_disk_num_bytes(path->nodes[0], fi);
6928                 btrfs_release_path(path);
6929                 cache = lookup_cache_extent(extent_cache, bytenr, 1);
6930                 if (cache) {
6931                         struct extent_record *tmp;
6932                         tmp = container_of(cache, struct extent_record, cache);
6933
6934                         /*
6935                          * If we found an extent record for the bytenr for this
6936                          * particular backref then we can't add it to our
6937                          * current extent record.  We only want to add backrefs
6938                          * that don't have a corresponding extent item in the
6939                          * extent tree since they likely belong to this record
6940                          * and we need to fix it if it doesn't match bytenrs.
6941                          */
6942                         if  (tmp->found_rec)
6943                                 continue;
6944                 }
6945
6946                 dback->found_ref += 1;
6947                 dback->disk_bytenr = bytenr;
6948                 dback->bytes = bytes;
6949
6950                 /*
6951                  * Set this so the verify backref code knows not to trust the
6952                  * values in this backref.
6953                  */
6954                 back->broken = 1;
6955         }
6956
6957         return 0;
6958 }
6959
6960 /*
6961  * Record orphan data ref into corresponding root.
6962  *
6963  * Return 0 if the extent item contains data ref and recorded.
6964  * Return 1 if the extent item contains no useful data ref
6965  *   On that case, it may contains only shared_dataref or metadata backref
6966  *   or the file extent exists(this should be handled by the extent bytenr
6967  *   recovery routine)
6968  * Return <0 if something goes wrong.
6969  */
6970 static int record_orphan_data_extents(struct btrfs_fs_info *fs_info,
6971                                       struct extent_record *rec)
6972 {
6973         struct btrfs_key key;
6974         struct btrfs_root *dest_root;
6975         struct extent_backref *back;
6976         struct data_backref *dback;
6977         struct orphan_data_extent *orphan;
6978         struct btrfs_path *path;
6979         int recorded_data_ref = 0;
6980         int ret = 0;
6981
6982         if (rec->metadata)
6983                 return 1;
6984         path = btrfs_alloc_path();
6985         if (!path)
6986                 return -ENOMEM;
6987         list_for_each_entry(back, &rec->backrefs, list) {
6988                 if (back->full_backref || !back->is_data ||
6989                     !back->found_extent_tree)
6990                         continue;
6991                 dback = (struct data_backref *)back;
6992                 if (dback->found_ref)
6993                         continue;
6994                 key.objectid = dback->root;
6995                 key.type = BTRFS_ROOT_ITEM_KEY;
6996                 key.offset = (u64)-1;
6997
6998                 dest_root = btrfs_read_fs_root(fs_info, &key);
6999
7000                 /* For non-exist root we just skip it */
7001                 if (IS_ERR(dest_root) || !dest_root)
7002                         continue;
7003
7004                 key.objectid = dback->owner;
7005                 key.type = BTRFS_EXTENT_DATA_KEY;
7006                 key.offset = dback->offset;
7007
7008                 ret = btrfs_search_slot(NULL, dest_root, &key, path, 0, 0);
7009                 /*
7010                  * For ret < 0, it's OK since the fs-tree may be corrupted,
7011                  * we need to record it for inode/file extent rebuild.
7012                  * For ret > 0, we record it only for file extent rebuild.
7013                  * For ret == 0, the file extent exists but only bytenr
7014                  * mismatch, let the original bytenr fix routine to handle,
7015                  * don't record it.
7016                  */
7017                 if (ret == 0)
7018                         continue;
7019                 ret = 0;
7020                 orphan = malloc(sizeof(*orphan));
7021                 if (!orphan) {
7022                         ret = -ENOMEM;
7023                         goto out;
7024                 }
7025                 INIT_LIST_HEAD(&orphan->list);
7026                 orphan->root = dback->root;
7027                 orphan->objectid = dback->owner;
7028                 orphan->offset = dback->offset;
7029                 orphan->disk_bytenr = rec->cache.start;
7030                 orphan->disk_len = rec->cache.size;
7031                 list_add(&dest_root->orphan_data_extents, &orphan->list);
7032                 recorded_data_ref = 1;
7033         }
7034 out:
7035         btrfs_free_path(path);
7036         if (!ret)
7037                 return !recorded_data_ref;
7038         else
7039                 return ret;
7040 }
7041
7042 /*
7043  * when an incorrect extent item is found, this will delete
7044  * all of the existing entries for it and recreate them
7045  * based on what the tree scan found.
7046  */
7047 static int fixup_extent_refs(struct btrfs_fs_info *info,
7048                              struct cache_tree *extent_cache,
7049                              struct extent_record *rec)
7050 {
7051         struct btrfs_trans_handle *trans = NULL;
7052         int ret;
7053         struct btrfs_path *path;
7054         struct list_head *cur = rec->backrefs.next;
7055         struct cache_extent *cache;
7056         struct extent_backref *back;
7057         int allocated = 0;
7058         u64 flags = 0;
7059
7060         if (rec->flag_block_full_backref)
7061                 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
7062
7063         path = btrfs_alloc_path();
7064         if (!path)
7065                 return -ENOMEM;
7066
7067         if (rec->refs != rec->extent_item_refs && !rec->metadata) {
7068                 /*
7069                  * Sometimes the backrefs themselves are so broken they don't
7070                  * get attached to any meaningful rec, so first go back and
7071                  * check any of our backrefs that we couldn't find and throw
7072                  * them into the list if we find the backref so that
7073                  * verify_backrefs can figure out what to do.
7074                  */
7075                 ret = find_possible_backrefs(info, path, extent_cache, rec);
7076                 if (ret < 0)
7077                         goto out;
7078         }
7079
7080         /* step one, make sure all of the backrefs agree */
7081         ret = verify_backrefs(info, path, rec);
7082         if (ret < 0)
7083                 goto out;
7084
7085         trans = btrfs_start_transaction(info->extent_root, 1);
7086         if (IS_ERR(trans)) {
7087                 ret = PTR_ERR(trans);
7088                 goto out;
7089         }
7090
7091         /* step two, delete all the existing records */
7092         ret = delete_extent_records(trans, info->extent_root, path,
7093                                     rec->start, rec->max_size);
7094
7095         if (ret < 0)
7096                 goto out;
7097
7098         /* was this block corrupt?  If so, don't add references to it */
7099         cache = lookup_cache_extent(info->corrupt_blocks,
7100                                     rec->start, rec->max_size);
7101         if (cache) {
7102                 ret = 0;
7103                 goto out;
7104         }
7105
7106         /* step three, recreate all the refs we did find */
7107         while(cur != &rec->backrefs) {
7108                 back = list_entry(cur, struct extent_backref, list);
7109                 cur = cur->next;
7110
7111                 /*
7112                  * if we didn't find any references, don't create a
7113                  * new extent record
7114                  */
7115                 if (!back->found_ref)
7116                         continue;
7117
7118                 rec->bad_full_backref = 0;
7119                 ret = record_extent(trans, info, path, rec, back, allocated, flags);
7120                 allocated = 1;
7121
7122                 if (ret)
7123                         goto out;
7124         }
7125 out:
7126         if (trans) {
7127                 int err = btrfs_commit_transaction(trans, info->extent_root);
7128                 if (!ret)
7129                         ret = err;
7130         }
7131
7132         btrfs_free_path(path);
7133         return ret;
7134 }
7135
7136 static int fixup_extent_flags(struct btrfs_fs_info *fs_info,
7137                               struct extent_record *rec)
7138 {
7139         struct btrfs_trans_handle *trans;
7140         struct btrfs_root *root = fs_info->extent_root;
7141         struct btrfs_path *path;
7142         struct btrfs_extent_item *ei;
7143         struct btrfs_key key;
7144         u64 flags;
7145         int ret = 0;
7146
7147         key.objectid = rec->start;
7148         if (rec->metadata) {
7149                 key.type = BTRFS_METADATA_ITEM_KEY;
7150                 key.offset = rec->info_level;
7151         } else {
7152                 key.type = BTRFS_EXTENT_ITEM_KEY;
7153                 key.offset = rec->max_size;
7154         }
7155
7156         path = btrfs_alloc_path();
7157         if (!path)
7158                 return -ENOMEM;
7159
7160         trans = btrfs_start_transaction(root, 0);
7161         if (IS_ERR(trans)) {
7162                 btrfs_free_path(path);
7163                 return PTR_ERR(trans);
7164         }
7165
7166         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
7167         if (ret < 0) {
7168                 btrfs_free_path(path);
7169                 btrfs_commit_transaction(trans, root);
7170                 return ret;
7171         } else if (ret) {
7172                 fprintf(stderr, "Didn't find extent for %llu\n",
7173                         (unsigned long long)rec->start);
7174                 btrfs_free_path(path);
7175                 btrfs_commit_transaction(trans, root);
7176                 return -ENOENT;
7177         }
7178
7179         ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
7180                             struct btrfs_extent_item);
7181         flags = btrfs_extent_flags(path->nodes[0], ei);
7182         if (rec->flag_block_full_backref) {
7183                 fprintf(stderr, "setting full backref on %llu\n",
7184                         (unsigned long long)key.objectid);
7185                 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
7186         } else {
7187                 fprintf(stderr, "clearing full backref on %llu\n",
7188                         (unsigned long long)key.objectid);
7189                 flags &= ~BTRFS_BLOCK_FLAG_FULL_BACKREF;
7190         }
7191         btrfs_set_extent_flags(path->nodes[0], ei, flags);
7192         btrfs_mark_buffer_dirty(path->nodes[0]);
7193         btrfs_free_path(path);
7194         return btrfs_commit_transaction(trans, root);
7195 }
7196
7197 /* right now we only prune from the extent allocation tree */
7198 static int prune_one_block(struct btrfs_trans_handle *trans,
7199                            struct btrfs_fs_info *info,
7200                            struct btrfs_corrupt_block *corrupt)
7201 {
7202         int ret;
7203         struct btrfs_path path;
7204         struct extent_buffer *eb;
7205         u64 found;
7206         int slot;
7207         int nritems;
7208         int level = corrupt->level + 1;
7209
7210         btrfs_init_path(&path);
7211 again:
7212         /* we want to stop at the parent to our busted block */
7213         path.lowest_level = level;
7214
7215         ret = btrfs_search_slot(trans, info->extent_root,
7216                                 &corrupt->key, &path, -1, 1);
7217
7218         if (ret < 0)
7219                 goto out;
7220
7221         eb = path.nodes[level];
7222         if (!eb) {
7223                 ret = -ENOENT;
7224                 goto out;
7225         }
7226
7227         /*
7228          * hopefully the search gave us the block we want to prune,
7229          * lets try that first
7230          */
7231         slot = path.slots[level];
7232         found =  btrfs_node_blockptr(eb, slot);
7233         if (found == corrupt->cache.start)
7234                 goto del_ptr;
7235
7236         nritems = btrfs_header_nritems(eb);
7237
7238         /* the search failed, lets scan this node and hope we find it */
7239         for (slot = 0; slot < nritems; slot++) {
7240                 found =  btrfs_node_blockptr(eb, slot);
7241                 if (found == corrupt->cache.start)
7242                         goto del_ptr;
7243         }
7244         /*
7245          * we couldn't find the bad block.  TODO, search all the nodes for pointers
7246          * to this block
7247          */
7248         if (eb == info->extent_root->node) {
7249                 ret = -ENOENT;
7250                 goto out;
7251         } else {
7252                 level++;
7253                 btrfs_release_path(&path);
7254                 goto again;
7255         }
7256
7257 del_ptr:
7258         printk("deleting pointer to block %Lu\n", corrupt->cache.start);
7259         ret = btrfs_del_ptr(trans, info->extent_root, &path, level, slot);
7260
7261 out:
7262         btrfs_release_path(&path);
7263         return ret;
7264 }
7265
7266 static int prune_corrupt_blocks(struct btrfs_fs_info *info)
7267 {
7268         struct btrfs_trans_handle *trans = NULL;
7269         struct cache_extent *cache;
7270         struct btrfs_corrupt_block *corrupt;
7271
7272         while (1) {
7273                 cache = search_cache_extent(info->corrupt_blocks, 0);
7274                 if (!cache)
7275                         break;
7276                 if (!trans) {
7277                         trans = btrfs_start_transaction(info->extent_root, 1);
7278                         if (IS_ERR(trans))
7279                                 return PTR_ERR(trans);
7280                 }
7281                 corrupt = container_of(cache, struct btrfs_corrupt_block, cache);
7282                 prune_one_block(trans, info, corrupt);
7283                 remove_cache_extent(info->corrupt_blocks, cache);
7284         }
7285         if (trans)
7286                 return btrfs_commit_transaction(trans, info->extent_root);
7287         return 0;
7288 }
7289
7290 static void reset_cached_block_groups(struct btrfs_fs_info *fs_info)
7291 {
7292         struct btrfs_block_group_cache *cache;
7293         u64 start, end;
7294         int ret;
7295
7296         while (1) {
7297                 ret = find_first_extent_bit(&fs_info->free_space_cache, 0,
7298                                             &start, &end, EXTENT_DIRTY);
7299                 if (ret)
7300                         break;
7301                 clear_extent_dirty(&fs_info->free_space_cache, start, end,
7302                                    GFP_NOFS);
7303         }
7304
7305         start = 0;
7306         while (1) {
7307                 cache = btrfs_lookup_first_block_group(fs_info, start);
7308                 if (!cache)
7309                         break;
7310                 if (cache->cached)
7311                         cache->cached = 0;
7312                 start = cache->key.objectid + cache->key.offset;
7313         }
7314 }
7315
7316 static int check_extent_refs(struct btrfs_root *root,
7317                              struct cache_tree *extent_cache)
7318 {
7319         struct extent_record *rec;
7320         struct cache_extent *cache;
7321         int err = 0;
7322         int ret = 0;
7323         int fixed = 0;
7324         int had_dups = 0;
7325         int recorded = 0;
7326
7327         if (repair) {
7328                 /*
7329                  * if we're doing a repair, we have to make sure
7330                  * we don't allocate from the problem extents.
7331                  * In the worst case, this will be all the
7332                  * extents in the FS
7333                  */
7334                 cache = search_cache_extent(extent_cache, 0);
7335                 while(cache) {
7336                         rec = container_of(cache, struct extent_record, cache);
7337                         set_extent_dirty(root->fs_info->excluded_extents,
7338                                          rec->start,
7339                                          rec->start + rec->max_size - 1,
7340                                          GFP_NOFS);
7341                         cache = next_cache_extent(cache);
7342                 }
7343
7344                 /* pin down all the corrupted blocks too */
7345                 cache = search_cache_extent(root->fs_info->corrupt_blocks, 0);
7346                 while(cache) {
7347                         set_extent_dirty(root->fs_info->excluded_extents,
7348                                          cache->start,
7349                                          cache->start + cache->size - 1,
7350                                          GFP_NOFS);
7351                         cache = next_cache_extent(cache);
7352                 }
7353                 prune_corrupt_blocks(root->fs_info);
7354                 reset_cached_block_groups(root->fs_info);
7355         }
7356
7357         reset_cached_block_groups(root->fs_info);
7358
7359         /*
7360          * We need to delete any duplicate entries we find first otherwise we
7361          * could mess up the extent tree when we have backrefs that actually
7362          * belong to a different extent item and not the weird duplicate one.
7363          */
7364         while (repair && !list_empty(&duplicate_extents)) {
7365                 rec = list_entry(duplicate_extents.next, struct extent_record,
7366                                  list);
7367                 list_del_init(&rec->list);
7368
7369                 /* Sometimes we can find a backref before we find an actual
7370                  * extent, so we need to process it a little bit to see if there
7371                  * truly are multiple EXTENT_ITEM_KEY's for the same range, or
7372                  * if this is a backref screwup.  If we need to delete stuff
7373                  * process_duplicates() will return 0, otherwise it will return
7374                  * 1 and we
7375                  */
7376                 if (process_duplicates(root, extent_cache, rec))
7377                         continue;
7378                 ret = delete_duplicate_records(root, rec);
7379                 if (ret < 0)
7380                         return ret;
7381                 /*
7382                  * delete_duplicate_records will return the number of entries
7383                  * deleted, so if it's greater than 0 then we know we actually
7384                  * did something and we need to remove.
7385                  */
7386                 if (ret)
7387                         had_dups = 1;
7388         }
7389
7390         if (had_dups)
7391                 return -EAGAIN;
7392
7393         while(1) {
7394                 int cur_err = 0;
7395
7396                 fixed = 0;
7397                 recorded = 0;
7398                 cache = search_cache_extent(extent_cache, 0);
7399                 if (!cache)
7400                         break;
7401                 rec = container_of(cache, struct extent_record, cache);
7402                 if (rec->num_duplicates) {
7403                         fprintf(stderr, "extent item %llu has multiple extent "
7404                                 "items\n", (unsigned long long)rec->start);
7405                         err = 1;
7406                         cur_err = 1;
7407                 }
7408
7409                 if (rec->refs != rec->extent_item_refs) {
7410                         fprintf(stderr, "ref mismatch on [%llu %llu] ",
7411                                 (unsigned long long)rec->start,
7412                                 (unsigned long long)rec->nr);
7413                         fprintf(stderr, "extent item %llu, found %llu\n",
7414                                 (unsigned long long)rec->extent_item_refs,
7415                                 (unsigned long long)rec->refs);
7416                         ret = record_orphan_data_extents(root->fs_info, rec);
7417                         if (ret < 0)
7418                                 goto repair_abort;
7419                         if (ret == 0) {
7420                                 recorded = 1;
7421                         } else {
7422                                 /*
7423                                  * we can't use the extent to repair file
7424                                  * extent, let the fallback method handle it.
7425                                  */
7426                                 if (!fixed && repair) {
7427                                         ret = fixup_extent_refs(
7428                                                         root->fs_info,
7429                                                         extent_cache, rec);
7430                                         if (ret)
7431                                                 goto repair_abort;
7432                                         fixed = 1;
7433                                 }
7434                         }
7435                         err = 1;
7436                         cur_err = 1;
7437                 }
7438                 if (all_backpointers_checked(rec, 1)) {
7439                         fprintf(stderr, "backpointer mismatch on [%llu %llu]\n",
7440                                 (unsigned long long)rec->start,
7441                                 (unsigned long long)rec->nr);
7442
7443                         if (!fixed && !recorded && repair) {
7444                                 ret = fixup_extent_refs(root->fs_info,
7445                                                         extent_cache, rec);
7446                                 if (ret)
7447                                         goto repair_abort;
7448                                 fixed = 1;
7449                         }
7450                         cur_err = 1;
7451                         err = 1;
7452                 }
7453                 if (!rec->owner_ref_checked) {
7454                         fprintf(stderr, "owner ref check failed [%llu %llu]\n",
7455                                 (unsigned long long)rec->start,
7456                                 (unsigned long long)rec->nr);
7457                         if (!fixed && !recorded && repair) {
7458                                 ret = fixup_extent_refs(root->fs_info,
7459                                                         extent_cache, rec);
7460                                 if (ret)
7461                                         goto repair_abort;
7462                                 fixed = 1;
7463                         }
7464                         err = 1;
7465                         cur_err = 1;
7466                 }
7467                 if (rec->bad_full_backref) {
7468                         fprintf(stderr, "bad full backref, on [%llu]\n",
7469                                 (unsigned long long)rec->start);
7470                         if (repair) {
7471                                 ret = fixup_extent_flags(root->fs_info, rec);
7472                                 if (ret)
7473                                         goto repair_abort;
7474                                 fixed = 1;
7475                         }
7476                         err = 1;
7477                         cur_err = 1;
7478                 }
7479
7480                 remove_cache_extent(extent_cache, cache);
7481                 free_all_extent_backrefs(rec);
7482                 if (!init_extent_tree && repair && (!cur_err || fixed))
7483                         clear_extent_dirty(root->fs_info->excluded_extents,
7484                                            rec->start,
7485                                            rec->start + rec->max_size - 1,
7486                                            GFP_NOFS);
7487                 free(rec);
7488         }
7489 repair_abort:
7490         if (repair) {
7491                 if (ret && ret != -EAGAIN) {
7492                         fprintf(stderr, "failed to repair damaged filesystem, aborting\n");
7493                         exit(1);
7494                 } else if (!ret) {
7495                         struct btrfs_trans_handle *trans;
7496
7497                         root = root->fs_info->extent_root;
7498                         trans = btrfs_start_transaction(root, 1);
7499                         if (IS_ERR(trans)) {
7500                                 ret = PTR_ERR(trans);
7501                                 goto repair_abort;
7502                         }
7503
7504                         btrfs_fix_block_accounting(trans, root);
7505                         ret = btrfs_commit_transaction(trans, root);
7506                         if (ret)
7507                                 goto repair_abort;
7508                 }
7509                 if (err)
7510                         fprintf(stderr, "repaired damaged extent references\n");
7511                 return ret;
7512         }
7513         return err;
7514 }
7515
7516 u64 calc_stripe_length(u64 type, u64 length, int num_stripes)
7517 {
7518         u64 stripe_size;
7519
7520         if (type & BTRFS_BLOCK_GROUP_RAID0) {
7521                 stripe_size = length;
7522                 stripe_size /= num_stripes;
7523         } else if (type & BTRFS_BLOCK_GROUP_RAID10) {
7524                 stripe_size = length * 2;
7525                 stripe_size /= num_stripes;
7526         } else if (type & BTRFS_BLOCK_GROUP_RAID5) {
7527                 stripe_size = length;
7528                 stripe_size /= (num_stripes - 1);
7529         } else if (type & BTRFS_BLOCK_GROUP_RAID6) {
7530                 stripe_size = length;
7531                 stripe_size /= (num_stripes - 2);
7532         } else {
7533                 stripe_size = length;
7534         }
7535         return stripe_size;
7536 }
7537
7538 /*
7539  * Check the chunk with its block group/dev list ref:
7540  * Return 0 if all refs seems valid.
7541  * Return 1 if part of refs seems valid, need later check for rebuild ref
7542  * like missing block group and needs to search extent tree to rebuild them.
7543  * Return -1 if essential refs are missing and unable to rebuild.
7544  */
7545 static int check_chunk_refs(struct chunk_record *chunk_rec,
7546                             struct block_group_tree *block_group_cache,
7547                             struct device_extent_tree *dev_extent_cache,
7548                             int silent)
7549 {
7550         struct cache_extent *block_group_item;
7551         struct block_group_record *block_group_rec;
7552         struct cache_extent *dev_extent_item;
7553         struct device_extent_record *dev_extent_rec;
7554         u64 devid;
7555         u64 offset;
7556         u64 length;
7557         int metadump_v2 = 0;
7558         int i;
7559         int ret = 0;
7560
7561         block_group_item = lookup_cache_extent(&block_group_cache->tree,
7562                                                chunk_rec->offset,
7563                                                chunk_rec->length);
7564         if (block_group_item) {
7565                 block_group_rec = container_of(block_group_item,
7566                                                struct block_group_record,
7567                                                cache);
7568                 if (chunk_rec->length != block_group_rec->offset ||
7569                     chunk_rec->offset != block_group_rec->objectid ||
7570                     (!metadump_v2 &&
7571                      chunk_rec->type_flags != block_group_rec->flags)) {
7572                         if (!silent)
7573                                 fprintf(stderr,
7574                                         "Chunk[%llu, %u, %llu]: length(%llu), offset(%llu), type(%llu) mismatch with block group[%llu, %u, %llu]: offset(%llu), objectid(%llu), flags(%llu)\n",
7575                                         chunk_rec->objectid,
7576                                         chunk_rec->type,
7577                                         chunk_rec->offset,
7578                                         chunk_rec->length,
7579                                         chunk_rec->offset,
7580                                         chunk_rec->type_flags,
7581                                         block_group_rec->objectid,
7582                                         block_group_rec->type,
7583                                         block_group_rec->offset,
7584                                         block_group_rec->offset,
7585                                         block_group_rec->objectid,
7586                                         block_group_rec->flags);
7587                         ret = -1;
7588                 } else {
7589                         list_del_init(&block_group_rec->list);
7590                         chunk_rec->bg_rec = block_group_rec;
7591                 }
7592         } else {
7593                 if (!silent)
7594                         fprintf(stderr,
7595                                 "Chunk[%llu, %u, %llu]: length(%llu), offset(%llu), type(%llu) is not found in block group\n",
7596                                 chunk_rec->objectid,
7597                                 chunk_rec->type,
7598                                 chunk_rec->offset,
7599                                 chunk_rec->length,
7600                                 chunk_rec->offset,
7601                                 chunk_rec->type_flags);
7602                 ret = 1;
7603         }
7604
7605         if (metadump_v2)
7606                 return ret;
7607
7608         length = calc_stripe_length(chunk_rec->type_flags, chunk_rec->length,
7609                                     chunk_rec->num_stripes);
7610         for (i = 0; i < chunk_rec->num_stripes; ++i) {
7611                 devid = chunk_rec->stripes[i].devid;
7612                 offset = chunk_rec->stripes[i].offset;
7613                 dev_extent_item = lookup_cache_extent2(&dev_extent_cache->tree,
7614                                                        devid, offset, length);
7615                 if (dev_extent_item) {
7616                         dev_extent_rec = container_of(dev_extent_item,
7617                                                 struct device_extent_record,
7618                                                 cache);
7619                         if (dev_extent_rec->objectid != devid ||
7620                             dev_extent_rec->offset != offset ||
7621                             dev_extent_rec->chunk_offset != chunk_rec->offset ||
7622                             dev_extent_rec->length != length) {
7623                                 if (!silent)
7624                                         fprintf(stderr,
7625                                                 "Chunk[%llu, %u, %llu] stripe[%llu, %llu] dismatch dev extent[%llu, %llu, %llu]\n",
7626                                                 chunk_rec->objectid,
7627                                                 chunk_rec->type,
7628                                                 chunk_rec->offset,
7629                                                 chunk_rec->stripes[i].devid,
7630                                                 chunk_rec->stripes[i].offset,
7631                                                 dev_extent_rec->objectid,
7632                                                 dev_extent_rec->offset,
7633                                                 dev_extent_rec->length);
7634                                 ret = -1;
7635                         } else {
7636                                 list_move(&dev_extent_rec->chunk_list,
7637                                           &chunk_rec->dextents);
7638                         }
7639                 } else {
7640                         if (!silent)
7641                                 fprintf(stderr,
7642                                         "Chunk[%llu, %u, %llu] stripe[%llu, %llu] is not found in dev extent\n",
7643                                         chunk_rec->objectid,
7644                                         chunk_rec->type,
7645                                         chunk_rec->offset,
7646                                         chunk_rec->stripes[i].devid,
7647                                         chunk_rec->stripes[i].offset);
7648                         ret = -1;
7649                 }
7650         }
7651         return ret;
7652 }
7653
7654 /* check btrfs_chunk -> btrfs_dev_extent / btrfs_block_group_item */
7655 int check_chunks(struct cache_tree *chunk_cache,
7656                  struct block_group_tree *block_group_cache,
7657                  struct device_extent_tree *dev_extent_cache,
7658                  struct list_head *good, struct list_head *bad,
7659                  struct list_head *rebuild, int silent)
7660 {
7661         struct cache_extent *chunk_item;
7662         struct chunk_record *chunk_rec;
7663         struct block_group_record *bg_rec;
7664         struct device_extent_record *dext_rec;
7665         int err;
7666         int ret = 0;
7667
7668         chunk_item = first_cache_extent(chunk_cache);
7669         while (chunk_item) {
7670                 chunk_rec = container_of(chunk_item, struct chunk_record,
7671                                          cache);
7672                 err = check_chunk_refs(chunk_rec, block_group_cache,
7673                                        dev_extent_cache, silent);
7674                 if (err < 0)
7675                         ret = err;
7676                 if (err == 0 && good)
7677                         list_add_tail(&chunk_rec->list, good);
7678                 if (err > 0 && rebuild)
7679                         list_add_tail(&chunk_rec->list, rebuild);
7680                 if (err < 0 && bad)
7681                         list_add_tail(&chunk_rec->list, bad);
7682                 chunk_item = next_cache_extent(chunk_item);
7683         }
7684
7685         list_for_each_entry(bg_rec, &block_group_cache->block_groups, list) {
7686                 if (!silent)
7687                         fprintf(stderr,
7688                                 "Block group[%llu, %llu] (flags = %llu) didn't find the relative chunk.\n",
7689                                 bg_rec->objectid,
7690                                 bg_rec->offset,
7691                                 bg_rec->flags);
7692                 if (!ret)
7693                         ret = 1;
7694         }
7695
7696         list_for_each_entry(dext_rec, &dev_extent_cache->no_chunk_orphans,
7697                             chunk_list) {
7698                 if (!silent)
7699                         fprintf(stderr,
7700                                 "Device extent[%llu, %llu, %llu] didn't find the relative chunk.\n",
7701                                 dext_rec->objectid,
7702                                 dext_rec->offset,
7703                                 dext_rec->length);
7704                 if (!ret)
7705                         ret = 1;
7706         }
7707         return ret;
7708 }
7709
7710
7711 static int check_device_used(struct device_record *dev_rec,
7712                              struct device_extent_tree *dext_cache)
7713 {
7714         struct cache_extent *cache;
7715         struct device_extent_record *dev_extent_rec;
7716         u64 total_byte = 0;
7717
7718         cache = search_cache_extent2(&dext_cache->tree, dev_rec->devid, 0);
7719         while (cache) {
7720                 dev_extent_rec = container_of(cache,
7721                                               struct device_extent_record,
7722                                               cache);
7723                 if (dev_extent_rec->objectid != dev_rec->devid)
7724                         break;
7725
7726                 list_del_init(&dev_extent_rec->device_list);
7727                 total_byte += dev_extent_rec->length;
7728                 cache = next_cache_extent(cache);
7729         }
7730
7731         if (total_byte != dev_rec->byte_used) {
7732                 fprintf(stderr,
7733                         "Dev extent's total-byte(%llu) is not equal to byte-used(%llu) in dev[%llu, %u, %llu]\n",
7734                         total_byte, dev_rec->byte_used, dev_rec->objectid,
7735                         dev_rec->type, dev_rec->offset);
7736                 return -1;
7737         } else {
7738                 return 0;
7739         }
7740 }
7741
7742 /* check btrfs_dev_item -> btrfs_dev_extent */
7743 static int check_devices(struct rb_root *dev_cache,
7744                          struct device_extent_tree *dev_extent_cache)
7745 {
7746         struct rb_node *dev_node;
7747         struct device_record *dev_rec;
7748         struct device_extent_record *dext_rec;
7749         int err;
7750         int ret = 0;
7751
7752         dev_node = rb_first(dev_cache);
7753         while (dev_node) {
7754                 dev_rec = container_of(dev_node, struct device_record, node);
7755                 err = check_device_used(dev_rec, dev_extent_cache);
7756                 if (err)
7757                         ret = err;
7758
7759                 dev_node = rb_next(dev_node);
7760         }
7761         list_for_each_entry(dext_rec, &dev_extent_cache->no_device_orphans,
7762                             device_list) {
7763                 fprintf(stderr,
7764                         "Device extent[%llu, %llu, %llu] didn't find its device.\n",
7765                         dext_rec->objectid, dext_rec->offset, dext_rec->length);
7766                 if (!ret)
7767                         ret = 1;
7768         }
7769         return ret;
7770 }
7771
7772 static int add_root_item_to_list(struct list_head *head,
7773                                   u64 objectid, u64 bytenr, u64 last_snapshot,
7774                                   u8 level, u8 drop_level,
7775                                   int level_size, struct btrfs_key *drop_key)
7776 {
7777
7778         struct root_item_record *ri_rec;
7779         ri_rec = malloc(sizeof(*ri_rec));
7780         if (!ri_rec)
7781                 return -ENOMEM;
7782         ri_rec->bytenr = bytenr;
7783         ri_rec->objectid = objectid;
7784         ri_rec->level = level;
7785         ri_rec->level_size = level_size;
7786         ri_rec->drop_level = drop_level;
7787         ri_rec->last_snapshot = last_snapshot;
7788         if (drop_key)
7789                 memcpy(&ri_rec->drop_key, drop_key, sizeof(*drop_key));
7790         list_add_tail(&ri_rec->list, head);
7791
7792         return 0;
7793 }
7794
7795 static void free_root_item_list(struct list_head *list)
7796 {
7797         struct root_item_record *ri_rec;
7798
7799         while (!list_empty(list)) {
7800                 ri_rec = list_first_entry(list, struct root_item_record,
7801                                           list);
7802                 list_del_init(&ri_rec->list);
7803                 free(ri_rec);
7804         }
7805 }
7806
7807 static int deal_root_from_list(struct list_head *list,
7808                                struct btrfs_root *root,
7809                                struct block_info *bits,
7810                                int bits_nr,
7811                                struct cache_tree *pending,
7812                                struct cache_tree *seen,
7813                                struct cache_tree *reada,
7814                                struct cache_tree *nodes,
7815                                struct cache_tree *extent_cache,
7816                                struct cache_tree *chunk_cache,
7817                                struct rb_root *dev_cache,
7818                                struct block_group_tree *block_group_cache,
7819                                struct device_extent_tree *dev_extent_cache)
7820 {
7821         int ret = 0;
7822         u64 last;
7823
7824         while (!list_empty(list)) {
7825                 struct root_item_record *rec;
7826                 struct extent_buffer *buf;
7827                 rec = list_entry(list->next,
7828                                  struct root_item_record, list);
7829                 last = 0;
7830                 buf = read_tree_block(root->fs_info->tree_root,
7831                                       rec->bytenr, rec->level_size, 0);
7832                 if (!extent_buffer_uptodate(buf)) {
7833                         free_extent_buffer(buf);
7834                         ret = -EIO;
7835                         break;
7836                 }
7837                 add_root_to_pending(buf, extent_cache, pending,
7838                                     seen, nodes, rec->objectid);
7839                 /*
7840                  * To rebuild extent tree, we need deal with snapshot
7841                  * one by one, otherwise we deal with node firstly which
7842                  * can maximize readahead.
7843                  */
7844                 while (1) {
7845                         ret = run_next_block(root, bits, bits_nr, &last,
7846                                              pending, seen, reada, nodes,
7847                                              extent_cache, chunk_cache,
7848                                              dev_cache, block_group_cache,
7849                                              dev_extent_cache, rec);
7850                         if (ret != 0)
7851                                 break;
7852                 }
7853                 free_extent_buffer(buf);
7854                 list_del(&rec->list);
7855                 free(rec);
7856                 if (ret < 0)
7857                         break;
7858         }
7859         while (ret >= 0) {
7860                 ret = run_next_block(root, bits, bits_nr, &last, pending, seen,
7861                                      reada, nodes, extent_cache, chunk_cache,
7862                                      dev_cache, block_group_cache,
7863                                      dev_extent_cache, NULL);
7864                 if (ret != 0) {
7865                         if (ret > 0)
7866                                 ret = 0;
7867                         break;
7868                 }
7869         }
7870         return ret;
7871 }
7872
7873 static int check_chunks_and_extents(struct btrfs_root *root)
7874 {
7875         struct rb_root dev_cache;
7876         struct cache_tree chunk_cache;
7877         struct block_group_tree block_group_cache;
7878         struct device_extent_tree dev_extent_cache;
7879         struct cache_tree extent_cache;
7880         struct cache_tree seen;
7881         struct cache_tree pending;
7882         struct cache_tree reada;
7883         struct cache_tree nodes;
7884         struct extent_io_tree excluded_extents;
7885         struct cache_tree corrupt_blocks;
7886         struct btrfs_path path;
7887         struct btrfs_key key;
7888         struct btrfs_key found_key;
7889         int ret, err = 0;
7890         struct block_info *bits;
7891         int bits_nr;
7892         struct extent_buffer *leaf;
7893         int slot;
7894         struct btrfs_root_item ri;
7895         struct list_head dropping_trees;
7896         struct list_head normal_trees;
7897         struct btrfs_root *root1;
7898         u64 objectid;
7899         u32 level_size;
7900         u8 level;
7901
7902         dev_cache = RB_ROOT;
7903         cache_tree_init(&chunk_cache);
7904         block_group_tree_init(&block_group_cache);
7905         device_extent_tree_init(&dev_extent_cache);
7906
7907         cache_tree_init(&extent_cache);
7908         cache_tree_init(&seen);
7909         cache_tree_init(&pending);
7910         cache_tree_init(&nodes);
7911         cache_tree_init(&reada);
7912         cache_tree_init(&corrupt_blocks);
7913         extent_io_tree_init(&excluded_extents);
7914         INIT_LIST_HEAD(&dropping_trees);
7915         INIT_LIST_HEAD(&normal_trees);
7916
7917         if (repair) {
7918                 root->fs_info->excluded_extents = &excluded_extents;
7919                 root->fs_info->fsck_extent_cache = &extent_cache;
7920                 root->fs_info->free_extent_hook = free_extent_hook;
7921                 root->fs_info->corrupt_blocks = &corrupt_blocks;
7922         }
7923
7924         bits_nr = 1024;
7925         bits = malloc(bits_nr * sizeof(struct block_info));
7926         if (!bits) {
7927                 perror("malloc");
7928                 exit(1);
7929         }
7930
7931 again:
7932         root1 = root->fs_info->tree_root;
7933         level = btrfs_header_level(root1->node);
7934         ret = add_root_item_to_list(&normal_trees, root1->root_key.objectid,
7935                                     root1->node->start, 0, level, 0,
7936                                     btrfs_level_size(root1, level), NULL);
7937         if (ret < 0)
7938                 goto out;
7939         root1 = root->fs_info->chunk_root;
7940         level = btrfs_header_level(root1->node);
7941         ret = add_root_item_to_list(&normal_trees, root1->root_key.objectid,
7942                                     root1->node->start, 0, level, 0,
7943                                     btrfs_level_size(root1, level), NULL);
7944         if (ret < 0)
7945                 goto out;
7946         btrfs_init_path(&path);
7947         key.offset = 0;
7948         key.objectid = 0;
7949         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
7950         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
7951                                         &key, &path, 0, 0);
7952         if (ret < 0)
7953                 goto out;
7954         while(1) {
7955                 leaf = path.nodes[0];
7956                 slot = path.slots[0];
7957                 if (slot >= btrfs_header_nritems(path.nodes[0])) {
7958                         ret = btrfs_next_leaf(root, &path);
7959                         if (ret != 0)
7960                                 break;
7961                         leaf = path.nodes[0];
7962                         slot = path.slots[0];
7963                 }
7964                 btrfs_item_key_to_cpu(leaf, &found_key, path.slots[0]);
7965                 if (btrfs_key_type(&found_key) == BTRFS_ROOT_ITEM_KEY) {
7966                         unsigned long offset;
7967                         u64 last_snapshot;
7968
7969                         offset = btrfs_item_ptr_offset(leaf, path.slots[0]);
7970                         read_extent_buffer(leaf, &ri, offset, sizeof(ri));
7971                         last_snapshot = btrfs_root_last_snapshot(&ri);
7972                         if (btrfs_disk_key_objectid(&ri.drop_progress) == 0) {
7973                                 level = btrfs_root_level(&ri);
7974                                 level_size = btrfs_level_size(root, level);
7975                                 ret = add_root_item_to_list(&normal_trees,
7976                                                 found_key.objectid,
7977                                                 btrfs_root_bytenr(&ri),
7978                                                 last_snapshot, level,
7979                                                 0, level_size, NULL);
7980                                 if (ret < 0)
7981                                         goto out;
7982                         } else {
7983                                 level = btrfs_root_level(&ri);
7984                                 level_size = btrfs_level_size(root, level);
7985                                 objectid = found_key.objectid;
7986                                 btrfs_disk_key_to_cpu(&found_key,
7987                                                       &ri.drop_progress);
7988                                 ret = add_root_item_to_list(&dropping_trees,
7989                                                 objectid,
7990                                                 btrfs_root_bytenr(&ri),
7991                                                 last_snapshot, level,
7992                                                 ri.drop_level,
7993                                                 level_size, &found_key);
7994                                 if (ret < 0)
7995                                         goto out;
7996                         }
7997                 }
7998                 path.slots[0]++;
7999         }
8000         btrfs_release_path(&path);
8001
8002         /*
8003          * check_block can return -EAGAIN if it fixes something, please keep
8004          * this in mind when dealing with return values from these functions, if
8005          * we get -EAGAIN we want to fall through and restart the loop.
8006          */
8007         ret = deal_root_from_list(&normal_trees, root, bits, bits_nr, &pending,
8008                                   &seen, &reada, &nodes, &extent_cache,
8009                                   &chunk_cache, &dev_cache, &block_group_cache,
8010                                   &dev_extent_cache);
8011         if (ret < 0) {
8012                 if (ret == -EAGAIN)
8013                         goto loop;
8014                 goto out;
8015         }
8016         ret = deal_root_from_list(&dropping_trees, root, bits, bits_nr,
8017                                   &pending, &seen, &reada, &nodes,
8018                                   &extent_cache, &chunk_cache, &dev_cache,
8019                                   &block_group_cache, &dev_extent_cache);
8020         if (ret < 0) {
8021                 if (ret == -EAGAIN)
8022                         goto loop;
8023                 goto out;
8024         }
8025
8026         err = check_chunks(&chunk_cache, &block_group_cache,
8027                            &dev_extent_cache, NULL, NULL, NULL, 0);
8028         if (err) {
8029                 if (err == -EAGAIN)
8030                         goto loop;
8031                 if (!ret)
8032                         ret = err;
8033         }
8034
8035         ret = check_extent_refs(root, &extent_cache);
8036         if (ret < 0) {
8037                 if (ret == -EAGAIN)
8038                         goto loop;
8039                 goto out;
8040         }
8041
8042         err = check_devices(&dev_cache, &dev_extent_cache);
8043         if (err && !ret)
8044                 ret = err;
8045
8046 out:
8047         if (repair) {
8048                 free_corrupt_blocks_tree(root->fs_info->corrupt_blocks);
8049                 extent_io_tree_cleanup(&excluded_extents);
8050                 root->fs_info->fsck_extent_cache = NULL;
8051                 root->fs_info->free_extent_hook = NULL;
8052                 root->fs_info->corrupt_blocks = NULL;
8053                 root->fs_info->excluded_extents = NULL;
8054         }
8055         free(bits);
8056         free_chunk_cache_tree(&chunk_cache);
8057         free_device_cache_tree(&dev_cache);
8058         free_block_group_tree(&block_group_cache);
8059         free_device_extent_tree(&dev_extent_cache);
8060         free_extent_cache_tree(&seen);
8061         free_extent_cache_tree(&pending);
8062         free_extent_cache_tree(&reada);
8063         free_extent_cache_tree(&nodes);
8064         return ret;
8065 loop:
8066         free_corrupt_blocks_tree(root->fs_info->corrupt_blocks);
8067         free_extent_cache_tree(&seen);
8068         free_extent_cache_tree(&pending);
8069         free_extent_cache_tree(&reada);
8070         free_extent_cache_tree(&nodes);
8071         free_chunk_cache_tree(&chunk_cache);
8072         free_block_group_tree(&block_group_cache);
8073         free_device_cache_tree(&dev_cache);
8074         free_device_extent_tree(&dev_extent_cache);
8075         free_extent_record_cache(root->fs_info, &extent_cache);
8076         free_root_item_list(&normal_trees);
8077         free_root_item_list(&dropping_trees);
8078         extent_io_tree_cleanup(&excluded_extents);
8079         goto again;
8080 }
8081
8082 static int btrfs_fsck_reinit_root(struct btrfs_trans_handle *trans,
8083                            struct btrfs_root *root, int overwrite)
8084 {
8085         struct extent_buffer *c;
8086         struct extent_buffer *old = root->node;
8087         int level;
8088         int ret;
8089         struct btrfs_disk_key disk_key = {0,0,0};
8090
8091         level = 0;
8092
8093         if (overwrite) {
8094                 c = old;
8095                 extent_buffer_get(c);
8096                 goto init;
8097         }
8098         c = btrfs_alloc_free_block(trans, root,
8099                                    btrfs_level_size(root, 0),
8100                                    root->root_key.objectid,
8101                                    &disk_key, level, 0, 0);
8102         if (IS_ERR(c)) {
8103                 c = old;
8104                 extent_buffer_get(c);
8105                 overwrite = 1;
8106         }
8107 init:
8108         memset_extent_buffer(c, 0, 0, sizeof(struct btrfs_header));
8109         btrfs_set_header_level(c, level);
8110         btrfs_set_header_bytenr(c, c->start);
8111         btrfs_set_header_generation(c, trans->transid);
8112         btrfs_set_header_backref_rev(c, BTRFS_MIXED_BACKREF_REV);
8113         btrfs_set_header_owner(c, root->root_key.objectid);
8114
8115         write_extent_buffer(c, root->fs_info->fsid,
8116                             btrfs_header_fsid(), BTRFS_FSID_SIZE);
8117
8118         write_extent_buffer(c, root->fs_info->chunk_tree_uuid,
8119                             btrfs_header_chunk_tree_uuid(c),
8120                             BTRFS_UUID_SIZE);
8121
8122         btrfs_mark_buffer_dirty(c);
8123         /*
8124          * this case can happen in the following case:
8125          *
8126          * 1.overwrite previous root.
8127          *
8128          * 2.reinit reloc data root, this is because we skip pin
8129          * down reloc data tree before which means we can allocate
8130          * same block bytenr here.
8131          */
8132         if (old->start == c->start) {
8133                 btrfs_set_root_generation(&root->root_item,
8134                                           trans->transid);
8135                 root->root_item.level = btrfs_header_level(root->node);
8136                 ret = btrfs_update_root(trans, root->fs_info->tree_root,
8137                                         &root->root_key, &root->root_item);
8138                 if (ret) {
8139                         free_extent_buffer(c);
8140                         return ret;
8141                 }
8142         }
8143         free_extent_buffer(old);
8144         root->node = c;
8145         add_root_to_dirty_list(root);
8146         return 0;
8147 }
8148
8149 static int pin_down_tree_blocks(struct btrfs_fs_info *fs_info,
8150                                 struct extent_buffer *eb, int tree_root)
8151 {
8152         struct extent_buffer *tmp;
8153         struct btrfs_root_item *ri;
8154         struct btrfs_key key;
8155         u64 bytenr;
8156         u32 leafsize;
8157         int level = btrfs_header_level(eb);
8158         int nritems;
8159         int ret;
8160         int i;
8161
8162         /*
8163          * If we have pinned this block before, don't pin it again.
8164          * This can not only avoid forever loop with broken filesystem
8165          * but also give us some speedups.
8166          */
8167         if (test_range_bit(&fs_info->pinned_extents, eb->start,
8168                            eb->start + eb->len - 1, EXTENT_DIRTY, 0))
8169                 return 0;
8170
8171         btrfs_pin_extent(fs_info, eb->start, eb->len);
8172
8173         leafsize = btrfs_super_leafsize(fs_info->super_copy);
8174         nritems = btrfs_header_nritems(eb);
8175         for (i = 0; i < nritems; i++) {
8176                 if (level == 0) {
8177                         btrfs_item_key_to_cpu(eb, &key, i);
8178                         if (key.type != BTRFS_ROOT_ITEM_KEY)
8179                                 continue;
8180                         /* Skip the extent root and reloc roots */
8181                         if (key.objectid == BTRFS_EXTENT_TREE_OBJECTID ||
8182                             key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
8183                             key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
8184                                 continue;
8185                         ri = btrfs_item_ptr(eb, i, struct btrfs_root_item);
8186                         bytenr = btrfs_disk_root_bytenr(eb, ri);
8187
8188                         /*
8189                          * If at any point we start needing the real root we
8190                          * will have to build a stump root for the root we are
8191                          * in, but for now this doesn't actually use the root so
8192                          * just pass in extent_root.
8193                          */
8194                         tmp = read_tree_block(fs_info->extent_root, bytenr,
8195                                               leafsize, 0);
8196                         if (!extent_buffer_uptodate(tmp)) {
8197                                 fprintf(stderr, "Error reading root block\n");
8198                                 return -EIO;
8199                         }
8200                         ret = pin_down_tree_blocks(fs_info, tmp, 0);
8201                         free_extent_buffer(tmp);
8202                         if (ret)
8203                                 return ret;
8204                 } else {
8205                         bytenr = btrfs_node_blockptr(eb, i);
8206
8207                         /* If we aren't the tree root don't read the block */
8208                         if (level == 1 && !tree_root) {
8209                                 btrfs_pin_extent(fs_info, bytenr, leafsize);
8210                                 continue;
8211                         }
8212
8213                         tmp = read_tree_block(fs_info->extent_root, bytenr,
8214                                               leafsize, 0);
8215                         if (!extent_buffer_uptodate(tmp)) {
8216                                 fprintf(stderr, "Error reading tree block\n");
8217                                 return -EIO;
8218                         }
8219                         ret = pin_down_tree_blocks(fs_info, tmp, tree_root);
8220                         free_extent_buffer(tmp);
8221                         if (ret)
8222                                 return ret;
8223                 }
8224         }
8225
8226         return 0;
8227 }
8228
8229 static int pin_metadata_blocks(struct btrfs_fs_info *fs_info)
8230 {
8231         int ret;
8232
8233         ret = pin_down_tree_blocks(fs_info, fs_info->chunk_root->node, 0);
8234         if (ret)
8235                 return ret;
8236
8237         return pin_down_tree_blocks(fs_info, fs_info->tree_root->node, 1);
8238 }
8239
8240 static int reset_block_groups(struct btrfs_fs_info *fs_info)
8241 {
8242         struct btrfs_block_group_cache *cache;
8243         struct btrfs_path *path;
8244         struct extent_buffer *leaf;
8245         struct btrfs_chunk *chunk;
8246         struct btrfs_key key;
8247         int ret;
8248         u64 start;
8249
8250         path = btrfs_alloc_path();
8251         if (!path)
8252                 return -ENOMEM;
8253
8254         key.objectid = 0;
8255         key.type = BTRFS_CHUNK_ITEM_KEY;
8256         key.offset = 0;
8257
8258         ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
8259         if (ret < 0) {
8260                 btrfs_free_path(path);
8261                 return ret;
8262         }
8263
8264         /*
8265          * We do this in case the block groups were screwed up and had alloc
8266          * bits that aren't actually set on the chunks.  This happens with
8267          * restored images every time and could happen in real life I guess.
8268          */
8269         fs_info->avail_data_alloc_bits = 0;
8270         fs_info->avail_metadata_alloc_bits = 0;
8271         fs_info->avail_system_alloc_bits = 0;
8272
8273         /* First we need to create the in-memory block groups */
8274         while (1) {
8275                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
8276                         ret = btrfs_next_leaf(fs_info->chunk_root, path);
8277                         if (ret < 0) {
8278                                 btrfs_free_path(path);
8279                                 return ret;
8280                         }
8281                         if (ret) {
8282                                 ret = 0;
8283                                 break;
8284                         }
8285                 }
8286                 leaf = path->nodes[0];
8287                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
8288                 if (key.type != BTRFS_CHUNK_ITEM_KEY) {
8289                         path->slots[0]++;
8290                         continue;
8291                 }
8292
8293                 chunk = btrfs_item_ptr(leaf, path->slots[0],
8294                                        struct btrfs_chunk);
8295                 btrfs_add_block_group(fs_info, 0,
8296                                       btrfs_chunk_type(leaf, chunk),
8297                                       key.objectid, key.offset,
8298                                       btrfs_chunk_length(leaf, chunk));
8299                 set_extent_dirty(&fs_info->free_space_cache, key.offset,
8300                                  key.offset + btrfs_chunk_length(leaf, chunk),
8301                                  GFP_NOFS);
8302                 path->slots[0]++;
8303         }
8304         start = 0;
8305         while (1) {
8306                 cache = btrfs_lookup_first_block_group(fs_info, start);
8307                 if (!cache)
8308                         break;
8309                 cache->cached = 1;
8310                 start = cache->key.objectid + cache->key.offset;
8311         }
8312
8313         btrfs_free_path(path);
8314         return 0;
8315 }
8316
8317 static int reset_balance(struct btrfs_trans_handle *trans,
8318                          struct btrfs_fs_info *fs_info)
8319 {
8320         struct btrfs_root *root = fs_info->tree_root;
8321         struct btrfs_path *path;
8322         struct extent_buffer *leaf;
8323         struct btrfs_key key;
8324         int del_slot, del_nr = 0;
8325         int ret;
8326         int found = 0;
8327
8328         path = btrfs_alloc_path();
8329         if (!path)
8330                 return -ENOMEM;
8331
8332         key.objectid = BTRFS_BALANCE_OBJECTID;
8333         key.type = BTRFS_BALANCE_ITEM_KEY;
8334         key.offset = 0;
8335
8336         ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8337         if (ret) {
8338                 if (ret > 0)
8339                         ret = 0;
8340                 if (!ret)
8341                         goto reinit_data_reloc;
8342                 else
8343                         goto out;
8344         }
8345
8346         ret = btrfs_del_item(trans, root, path);
8347         if (ret)
8348                 goto out;
8349         btrfs_release_path(path);
8350
8351         key.objectid = BTRFS_TREE_RELOC_OBJECTID;
8352         key.type = BTRFS_ROOT_ITEM_KEY;
8353         key.offset = 0;
8354
8355         ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8356         if (ret < 0)
8357                 goto out;
8358         while (1) {
8359                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
8360                         if (!found)
8361                                 break;
8362
8363                         if (del_nr) {
8364                                 ret = btrfs_del_items(trans, root, path,
8365                                                       del_slot, del_nr);
8366                                 del_nr = 0;
8367                                 if (ret)
8368                                         goto out;
8369                         }
8370                         key.offset++;
8371                         btrfs_release_path(path);
8372
8373                         found = 0;
8374                         ret = btrfs_search_slot(trans, root, &key, path,
8375                                                 -1, 1);
8376                         if (ret < 0)
8377                                 goto out;
8378                         continue;
8379                 }
8380                 found = 1;
8381                 leaf = path->nodes[0];
8382                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
8383                 if (key.objectid > BTRFS_TREE_RELOC_OBJECTID)
8384                         break;
8385                 if (key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
8386                         path->slots[0]++;
8387                         continue;
8388                 }
8389                 if (!del_nr) {
8390                         del_slot = path->slots[0];
8391                         del_nr = 1;
8392                 } else {
8393                         del_nr++;
8394                 }
8395                 path->slots[0]++;
8396         }
8397
8398         if (del_nr) {
8399                 ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
8400                 if (ret)
8401                         goto out;
8402         }
8403         btrfs_release_path(path);
8404
8405 reinit_data_reloc:
8406         key.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
8407         key.type = BTRFS_ROOT_ITEM_KEY;
8408         key.offset = (u64)-1;
8409         root = btrfs_read_fs_root(fs_info, &key);
8410         if (IS_ERR(root)) {
8411                 fprintf(stderr, "Error reading data reloc tree\n");
8412                 ret = PTR_ERR(root);
8413                 goto out;
8414         }
8415         record_root_in_trans(trans, root);
8416         ret = btrfs_fsck_reinit_root(trans, root, 0);
8417         if (ret)
8418                 goto out;
8419         ret = btrfs_make_root_dir(trans, root, BTRFS_FIRST_FREE_OBJECTID);
8420 out:
8421         btrfs_free_path(path);
8422         return ret;
8423 }
8424
8425 static int reinit_extent_tree(struct btrfs_trans_handle *trans,
8426                               struct btrfs_fs_info *fs_info)
8427 {
8428         u64 start = 0;
8429         int ret;
8430
8431         /*
8432          * The only reason we don't do this is because right now we're just
8433          * walking the trees we find and pinning down their bytes, we don't look
8434          * at any of the leaves.  In order to do mixed groups we'd have to check
8435          * the leaves of any fs roots and pin down the bytes for any file
8436          * extents we find.  Not hard but why do it if we don't have to?
8437          */
8438         if (btrfs_fs_incompat(fs_info, BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)) {
8439                 fprintf(stderr, "We don't support re-initing the extent tree "
8440                         "for mixed block groups yet, please notify a btrfs "
8441                         "developer you want to do this so they can add this "
8442                         "functionality.\n");
8443                 return -EINVAL;
8444         }
8445
8446         /*
8447          * first we need to walk all of the trees except the extent tree and pin
8448          * down the bytes that are in use so we don't overwrite any existing
8449          * metadata.
8450          */
8451         ret = pin_metadata_blocks(fs_info);
8452         if (ret) {
8453                 fprintf(stderr, "error pinning down used bytes\n");
8454                 return ret;
8455         }
8456
8457         /*
8458          * Need to drop all the block groups since we're going to recreate all
8459          * of them again.
8460          */
8461         btrfs_free_block_groups(fs_info);
8462         ret = reset_block_groups(fs_info);
8463         if (ret) {
8464                 fprintf(stderr, "error resetting the block groups\n");
8465                 return ret;
8466         }
8467
8468         /* Ok we can allocate now, reinit the extent root */
8469         ret = btrfs_fsck_reinit_root(trans, fs_info->extent_root, 0);
8470         if (ret) {
8471                 fprintf(stderr, "extent root initialization failed\n");
8472                 /*
8473                  * When the transaction code is updated we should end the
8474                  * transaction, but for now progs only knows about commit so
8475                  * just return an error.
8476                  */
8477                 return ret;
8478         }
8479
8480         /*
8481          * Now we have all the in-memory block groups setup so we can make
8482          * allocations properly, and the metadata we care about is safe since we
8483          * pinned all of it above.
8484          */
8485         while (1) {
8486                 struct btrfs_block_group_cache *cache;
8487
8488                 cache = btrfs_lookup_first_block_group(fs_info, start);
8489                 if (!cache)
8490                         break;
8491                 start = cache->key.objectid + cache->key.offset;
8492                 ret = btrfs_insert_item(trans, fs_info->extent_root,
8493                                         &cache->key, &cache->item,
8494                                         sizeof(cache->item));
8495                 if (ret) {
8496                         fprintf(stderr, "Error adding block group\n");
8497                         return ret;
8498                 }
8499                 btrfs_extent_post_op(trans, fs_info->extent_root);
8500         }
8501
8502         ret = reset_balance(trans, fs_info);
8503         if (ret)
8504                 fprintf(stderr, "error reseting the pending balance\n");
8505
8506         return ret;
8507 }
8508
8509 static int recow_extent_buffer(struct btrfs_root *root, struct extent_buffer *eb)
8510 {
8511         struct btrfs_path *path;
8512         struct btrfs_trans_handle *trans;
8513         struct btrfs_key key;
8514         int ret;
8515
8516         printf("Recowing metadata block %llu\n", eb->start);
8517         key.objectid = btrfs_header_owner(eb);
8518         key.type = BTRFS_ROOT_ITEM_KEY;
8519         key.offset = (u64)-1;
8520
8521         root = btrfs_read_fs_root(root->fs_info, &key);
8522         if (IS_ERR(root)) {
8523                 fprintf(stderr, "Couldn't find owner root %llu\n",
8524                         key.objectid);
8525                 return PTR_ERR(root);
8526         }
8527
8528         path = btrfs_alloc_path();
8529         if (!path)
8530                 return -ENOMEM;
8531
8532         trans = btrfs_start_transaction(root, 1);
8533         if (IS_ERR(trans)) {
8534                 btrfs_free_path(path);
8535                 return PTR_ERR(trans);
8536         }
8537
8538         path->lowest_level = btrfs_header_level(eb);
8539         if (path->lowest_level)
8540                 btrfs_node_key_to_cpu(eb, &key, 0);
8541         else
8542                 btrfs_item_key_to_cpu(eb, &key, 0);
8543
8544         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
8545         btrfs_commit_transaction(trans, root);
8546         btrfs_free_path(path);
8547         return ret;
8548 }
8549
8550 static int delete_bad_item(struct btrfs_root *root, struct bad_item *bad)
8551 {
8552         struct btrfs_path *path;
8553         struct btrfs_trans_handle *trans;
8554         struct btrfs_key key;
8555         int ret;
8556
8557         printf("Deleting bad item [%llu,%u,%llu]\n", bad->key.objectid,
8558                bad->key.type, bad->key.offset);
8559         key.objectid = bad->root_id;
8560         key.type = BTRFS_ROOT_ITEM_KEY;
8561         key.offset = (u64)-1;
8562
8563         root = btrfs_read_fs_root(root->fs_info, &key);
8564         if (IS_ERR(root)) {
8565                 fprintf(stderr, "Couldn't find owner root %llu\n",
8566                         key.objectid);
8567                 return PTR_ERR(root);
8568         }
8569
8570         path = btrfs_alloc_path();
8571         if (!path)
8572                 return -ENOMEM;
8573
8574         trans = btrfs_start_transaction(root, 1);
8575         if (IS_ERR(trans)) {
8576                 btrfs_free_path(path);
8577                 return PTR_ERR(trans);
8578         }
8579
8580         ret = btrfs_search_slot(trans, root, &bad->key, path, -1, 1);
8581         if (ret) {
8582                 if (ret > 0)
8583                         ret = 0;
8584                 goto out;
8585         }
8586         ret = btrfs_del_item(trans, root, path);
8587 out:
8588         btrfs_commit_transaction(trans, root);
8589         btrfs_free_path(path);
8590         return ret;
8591 }
8592
8593 static int zero_log_tree(struct btrfs_root *root)
8594 {
8595         struct btrfs_trans_handle *trans;
8596         int ret;
8597
8598         trans = btrfs_start_transaction(root, 1);
8599         if (IS_ERR(trans)) {
8600                 ret = PTR_ERR(trans);
8601                 return ret;
8602         }
8603         btrfs_set_super_log_root(root->fs_info->super_copy, 0);
8604         btrfs_set_super_log_root_level(root->fs_info->super_copy, 0);
8605         ret = btrfs_commit_transaction(trans, root);
8606         return ret;
8607 }
8608
8609 static int populate_csum(struct btrfs_trans_handle *trans,
8610                          struct btrfs_root *csum_root, char *buf, u64 start,
8611                          u64 len)
8612 {
8613         u64 offset = 0;
8614         u64 sectorsize;
8615         int ret = 0;
8616
8617         while (offset < len) {
8618                 sectorsize = csum_root->sectorsize;
8619                 ret = read_extent_data(csum_root, buf, start + offset,
8620                                        &sectorsize, 0);
8621                 if (ret)
8622                         break;
8623                 ret = btrfs_csum_file_block(trans, csum_root, start + len,
8624                                             start + offset, buf, sectorsize);
8625                 if (ret)
8626                         break;
8627                 offset += sectorsize;
8628         }
8629         return ret;
8630 }
8631
8632 static int fill_csum_tree_from_one_fs_root(struct btrfs_trans_handle *trans,
8633                                       struct btrfs_root *csum_root,
8634                                       struct btrfs_root *cur_root)
8635 {
8636         struct btrfs_path *path;
8637         struct btrfs_key key;
8638         struct extent_buffer *node;
8639         struct btrfs_file_extent_item *fi;
8640         char *buf = NULL;
8641         u64 start = 0;
8642         u64 len = 0;
8643         int slot = 0;
8644         int ret = 0;
8645
8646         path = btrfs_alloc_path();
8647         if (!path)
8648                 return -ENOMEM;
8649         buf = malloc(cur_root->fs_info->csum_root->sectorsize);
8650         if (!buf) {
8651                 ret = -ENOMEM;
8652                 goto out;
8653         }
8654
8655         key.objectid = 0;
8656         key.offset = 0;
8657         key.type = 0;
8658
8659         ret = btrfs_search_slot(NULL, cur_root, &key, path, 0, 0);
8660         if (ret < 0)
8661                 goto out;
8662         /* Iterate all regular file extents and fill its csum */
8663         while (1) {
8664                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
8665
8666                 if (key.type != BTRFS_EXTENT_DATA_KEY)
8667                         goto next;
8668                 node = path->nodes[0];
8669                 slot = path->slots[0];
8670                 fi = btrfs_item_ptr(node, slot, struct btrfs_file_extent_item);
8671                 if (btrfs_file_extent_type(node, fi) != BTRFS_FILE_EXTENT_REG)
8672                         goto next;
8673                 start = btrfs_file_extent_disk_bytenr(node, fi);
8674                 len = btrfs_file_extent_disk_num_bytes(node, fi);
8675
8676                 ret = populate_csum(trans, csum_root, buf, start, len);
8677                 if (ret == -EEXIST)
8678                         ret = 0;
8679                 if (ret < 0)
8680                         goto out;
8681 next:
8682                 /*
8683                  * TODO: if next leaf is corrupted, jump to nearest next valid
8684                  * leaf.
8685                  */
8686                 ret = btrfs_next_item(cur_root, path);
8687                 if (ret < 0)
8688                         goto out;
8689                 if (ret > 0) {
8690                         ret = 0;
8691                         goto out;
8692                 }
8693         }
8694
8695 out:
8696         btrfs_free_path(path);
8697         free(buf);
8698         return ret;
8699 }
8700
8701 static int fill_csum_tree_from_fs(struct btrfs_trans_handle *trans,
8702                                   struct btrfs_root *csum_root)
8703 {
8704         struct btrfs_fs_info *fs_info = csum_root->fs_info;
8705         struct btrfs_path *path;
8706         struct btrfs_root *tree_root = fs_info->tree_root;
8707         struct btrfs_root *cur_root;
8708         struct extent_buffer *node;
8709         struct btrfs_key key;
8710         int slot = 0;
8711         int ret = 0;
8712
8713         path = btrfs_alloc_path();
8714         if (!path)
8715                 return -ENOMEM;
8716
8717         key.objectid = BTRFS_FS_TREE_OBJECTID;
8718         key.offset = 0;
8719         key.type = BTRFS_ROOT_ITEM_KEY;
8720
8721         ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
8722         if (ret < 0)
8723                 goto out;
8724         if (ret > 0) {
8725                 ret = -ENOENT;
8726                 goto out;
8727         }
8728
8729         while (1) {
8730                 node = path->nodes[0];
8731                 slot = path->slots[0];
8732                 btrfs_item_key_to_cpu(node, &key, slot);
8733                 if (key.objectid > BTRFS_LAST_FREE_OBJECTID)
8734                         goto out;
8735                 if (key.type != BTRFS_ROOT_ITEM_KEY)
8736                         goto next;
8737                 if (!is_fstree(key.objectid))
8738                         goto next;
8739                 key.offset = (u64)-1;
8740
8741                 cur_root = btrfs_read_fs_root(fs_info, &key);
8742                 if (IS_ERR(cur_root) || !cur_root) {
8743                         fprintf(stderr, "Fail to read fs/subvol tree: %lld\n",
8744                                 key.objectid);
8745                         goto out;
8746                 }
8747                 ret = fill_csum_tree_from_one_fs_root(trans, csum_root,
8748                                 cur_root);
8749                 if (ret < 0)
8750                         goto out;
8751 next:
8752                 ret = btrfs_next_item(tree_root, path);
8753                 if (ret > 0) {
8754                         ret = 0;
8755                         goto out;
8756                 }
8757                 if (ret < 0)
8758                         goto out;
8759         }
8760
8761 out:
8762         btrfs_free_path(path);
8763         return ret;
8764 }
8765
8766 static int fill_csum_tree_from_extent(struct btrfs_trans_handle *trans,
8767                                       struct btrfs_root *csum_root)
8768 {
8769         struct btrfs_root *extent_root = csum_root->fs_info->extent_root;
8770         struct btrfs_path *path;
8771         struct btrfs_extent_item *ei;
8772         struct extent_buffer *leaf;
8773         char *buf;
8774         struct btrfs_key key;
8775         int ret;
8776
8777         path = btrfs_alloc_path();
8778         if (!path)
8779                 return -ENOMEM;
8780
8781         key.objectid = 0;
8782         key.type = BTRFS_EXTENT_ITEM_KEY;
8783         key.offset = 0;
8784
8785         ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
8786         if (ret < 0) {
8787                 btrfs_free_path(path);
8788                 return ret;
8789         }
8790
8791         buf = malloc(csum_root->sectorsize);
8792         if (!buf) {
8793                 btrfs_free_path(path);
8794                 return -ENOMEM;
8795         }
8796
8797         while (1) {
8798                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
8799                         ret = btrfs_next_leaf(extent_root, path);
8800                         if (ret < 0)
8801                                 break;
8802                         if (ret) {
8803                                 ret = 0;
8804                                 break;
8805                         }
8806                 }
8807                 leaf = path->nodes[0];
8808
8809                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
8810                 if (key.type != BTRFS_EXTENT_ITEM_KEY) {
8811                         path->slots[0]++;
8812                         continue;
8813                 }
8814
8815                 ei = btrfs_item_ptr(leaf, path->slots[0],
8816                                     struct btrfs_extent_item);
8817                 if (!(btrfs_extent_flags(leaf, ei) &
8818                       BTRFS_EXTENT_FLAG_DATA)) {
8819                         path->slots[0]++;
8820                         continue;
8821                 }
8822
8823                 ret = populate_csum(trans, csum_root, buf, key.objectid,
8824                                     key.offset);
8825                 if (ret)
8826                         break;
8827                 path->slots[0]++;
8828         }
8829
8830         btrfs_free_path(path);
8831         free(buf);
8832         return ret;
8833 }
8834
8835 /*
8836  * Recalculate the csum and put it into the csum tree.
8837  *
8838  * Extent tree init will wipe out all the extent info, so in that case, we
8839  * can't depend on extent tree, but use fs tree.  If search_fs_tree is set, we
8840  * will use fs/subvol trees to init the csum tree.
8841  */
8842 static int fill_csum_tree(struct btrfs_trans_handle *trans,
8843                           struct btrfs_root *csum_root,
8844                           int search_fs_tree)
8845 {
8846         if (search_fs_tree)
8847                 return fill_csum_tree_from_fs(trans, csum_root);
8848         else
8849                 return fill_csum_tree_from_extent(trans, csum_root);
8850 }
8851
8852 struct root_item_info {
8853         /* level of the root */
8854         u8 level;
8855         /* number of nodes at this level, must be 1 for a root */
8856         int node_count;
8857         u64 bytenr;
8858         u64 gen;
8859         struct cache_extent cache_extent;
8860 };
8861
8862 static struct cache_tree *roots_info_cache = NULL;
8863
8864 static void free_roots_info_cache(void)
8865 {
8866         if (!roots_info_cache)
8867                 return;
8868
8869         while (!cache_tree_empty(roots_info_cache)) {
8870                 struct cache_extent *entry;
8871                 struct root_item_info *rii;
8872
8873                 entry = first_cache_extent(roots_info_cache);
8874                 if (!entry)
8875                         break;
8876                 remove_cache_extent(roots_info_cache, entry);
8877                 rii = container_of(entry, struct root_item_info, cache_extent);
8878                 free(rii);
8879         }
8880
8881         free(roots_info_cache);
8882         roots_info_cache = NULL;
8883 }
8884
8885 static int build_roots_info_cache(struct btrfs_fs_info *info)
8886 {
8887         int ret = 0;
8888         struct btrfs_key key;
8889         struct extent_buffer *leaf;
8890         struct btrfs_path *path;
8891
8892         if (!roots_info_cache) {
8893                 roots_info_cache = malloc(sizeof(*roots_info_cache));
8894                 if (!roots_info_cache)
8895                         return -ENOMEM;
8896                 cache_tree_init(roots_info_cache);
8897         }
8898
8899         path = btrfs_alloc_path();
8900         if (!path)
8901                 return -ENOMEM;
8902
8903         key.objectid = 0;
8904         key.type = BTRFS_EXTENT_ITEM_KEY;
8905         key.offset = 0;
8906
8907         ret = btrfs_search_slot(NULL, info->extent_root, &key, path, 0, 0);
8908         if (ret < 0)
8909                 goto out;
8910         leaf = path->nodes[0];
8911
8912         while (1) {
8913                 struct btrfs_key found_key;
8914                 struct btrfs_extent_item *ei;
8915                 struct btrfs_extent_inline_ref *iref;
8916                 int slot = path->slots[0];
8917                 int type;
8918                 u64 flags;
8919                 u64 root_id;
8920                 u8 level;
8921                 struct cache_extent *entry;
8922                 struct root_item_info *rii;
8923
8924                 if (slot >= btrfs_header_nritems(leaf)) {
8925                         ret = btrfs_next_leaf(info->extent_root, path);
8926                         if (ret < 0) {
8927                                 break;
8928                         } else if (ret) {
8929                                 ret = 0;
8930                                 break;
8931                         }
8932                         leaf = path->nodes[0];
8933                         slot = path->slots[0];
8934                 }
8935
8936                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
8937
8938                 if (found_key.type != BTRFS_EXTENT_ITEM_KEY &&
8939                     found_key.type != BTRFS_METADATA_ITEM_KEY)
8940                         goto next;
8941
8942                 ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
8943                 flags = btrfs_extent_flags(leaf, ei);
8944
8945                 if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
8946                     !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
8947                         goto next;
8948
8949                 if (found_key.type == BTRFS_METADATA_ITEM_KEY) {
8950                         iref = (struct btrfs_extent_inline_ref *)(ei + 1);
8951                         level = found_key.offset;
8952                 } else {
8953                         struct btrfs_tree_block_info *info;
8954
8955                         info = (struct btrfs_tree_block_info *)(ei + 1);
8956                         iref = (struct btrfs_extent_inline_ref *)(info + 1);
8957                         level = btrfs_tree_block_level(leaf, info);
8958                 }
8959
8960                 /*
8961                  * For a root extent, it must be of the following type and the
8962                  * first (and only one) iref in the item.
8963                  */
8964                 type = btrfs_extent_inline_ref_type(leaf, iref);
8965                 if (type != BTRFS_TREE_BLOCK_REF_KEY)
8966                         goto next;
8967
8968                 root_id = btrfs_extent_inline_ref_offset(leaf, iref);
8969                 entry = lookup_cache_extent(roots_info_cache, root_id, 1);
8970                 if (!entry) {
8971                         rii = malloc(sizeof(struct root_item_info));
8972                         if (!rii) {
8973                                 ret = -ENOMEM;
8974                                 goto out;
8975                         }
8976                         rii->cache_extent.start = root_id;
8977                         rii->cache_extent.size = 1;
8978                         rii->level = (u8)-1;
8979                         entry = &rii->cache_extent;
8980                         ret = insert_cache_extent(roots_info_cache, entry);
8981                         ASSERT(ret == 0);
8982                 } else {
8983                         rii = container_of(entry, struct root_item_info,
8984                                            cache_extent);
8985                 }
8986
8987                 ASSERT(rii->cache_extent.start == root_id);
8988                 ASSERT(rii->cache_extent.size == 1);
8989
8990                 if (level > rii->level || rii->level == (u8)-1) {
8991                         rii->level = level;
8992                         rii->bytenr = found_key.objectid;
8993                         rii->gen = btrfs_extent_generation(leaf, ei);
8994                         rii->node_count = 1;
8995                 } else if (level == rii->level) {
8996                         rii->node_count++;
8997                 }
8998 next:
8999                 path->slots[0]++;
9000         }
9001
9002 out:
9003         btrfs_free_path(path);
9004
9005         return ret;
9006 }
9007
9008 static int maybe_repair_root_item(struct btrfs_fs_info *info,
9009                                   struct btrfs_path *path,
9010                                   const struct btrfs_key *root_key,
9011                                   const int read_only_mode)
9012 {
9013         const u64 root_id = root_key->objectid;
9014         struct cache_extent *entry;
9015         struct root_item_info *rii;
9016         struct btrfs_root_item ri;
9017         unsigned long offset;
9018
9019         entry = lookup_cache_extent(roots_info_cache, root_id, 1);
9020         if (!entry) {
9021                 fprintf(stderr,
9022                         "Error: could not find extent items for root %llu\n",
9023                         root_key->objectid);
9024                 return -ENOENT;
9025         }
9026
9027         rii = container_of(entry, struct root_item_info, cache_extent);
9028         ASSERT(rii->cache_extent.start == root_id);
9029         ASSERT(rii->cache_extent.size == 1);
9030
9031         if (rii->node_count != 1) {
9032                 fprintf(stderr,
9033                         "Error: could not find btree root extent for root %llu\n",
9034                         root_id);
9035                 return -ENOENT;
9036         }
9037
9038         offset = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
9039         read_extent_buffer(path->nodes[0], &ri, offset, sizeof(ri));
9040
9041         if (btrfs_root_bytenr(&ri) != rii->bytenr ||
9042             btrfs_root_level(&ri) != rii->level ||
9043             btrfs_root_generation(&ri) != rii->gen) {
9044
9045                 /*
9046                  * If we're in repair mode but our caller told us to not update
9047                  * the root item, i.e. just check if it needs to be updated, don't
9048                  * print this message, since the caller will call us again shortly
9049                  * for the same root item without read only mode (the caller will
9050                  * open a transaction first).
9051                  */
9052                 if (!(read_only_mode && repair))
9053                         fprintf(stderr,
9054                                 "%sroot item for root %llu,"
9055                                 " current bytenr %llu, current gen %llu, current level %u,"
9056                                 " new bytenr %llu, new gen %llu, new level %u\n",
9057                                 (read_only_mode ? "" : "fixing "),
9058                                 root_id,
9059                                 btrfs_root_bytenr(&ri), btrfs_root_generation(&ri),
9060                                 btrfs_root_level(&ri),
9061                                 rii->bytenr, rii->gen, rii->level);
9062
9063                 if (btrfs_root_generation(&ri) > rii->gen) {
9064                         fprintf(stderr,
9065                                 "root %llu has a root item with a more recent gen (%llu) compared to the found root node (%llu)\n",
9066                                 root_id, btrfs_root_generation(&ri), rii->gen);
9067                         return -EINVAL;
9068                 }
9069
9070                 if (!read_only_mode) {
9071                         btrfs_set_root_bytenr(&ri, rii->bytenr);
9072                         btrfs_set_root_level(&ri, rii->level);
9073                         btrfs_set_root_generation(&ri, rii->gen);
9074                         write_extent_buffer(path->nodes[0], &ri,
9075                                             offset, sizeof(ri));
9076                 }
9077
9078                 return 1;
9079         }
9080
9081         return 0;
9082 }
9083
9084 /*
9085  * A regression introduced in the 3.17 kernel (more specifically in 3.17-rc2),
9086  * caused read-only snapshots to be corrupted if they were created at a moment
9087  * when the source subvolume/snapshot had orphan items. The issue was that the
9088  * on-disk root items became incorrect, referring to the pre orphan cleanup root
9089  * node instead of the post orphan cleanup root node.
9090  * So this function, and its callees, just detects and fixes those cases. Even
9091  * though the regression was for read-only snapshots, this function applies to
9092  * any snapshot/subvolume root.
9093  * This must be run before any other repair code - not doing it so, makes other
9094  * repair code delete or modify backrefs in the extent tree for example, which
9095  * will result in an inconsistent fs after repairing the root items.
9096  */
9097 static int repair_root_items(struct btrfs_fs_info *info)
9098 {
9099         struct btrfs_path *path = NULL;
9100         struct btrfs_key key;
9101         struct extent_buffer *leaf;
9102         struct btrfs_trans_handle *trans = NULL;
9103         int ret = 0;
9104         int bad_roots = 0;
9105         int need_trans = 0;
9106
9107         ret = build_roots_info_cache(info);
9108         if (ret)
9109                 goto out;
9110
9111         path = btrfs_alloc_path();
9112         if (!path) {
9113                 ret = -ENOMEM;
9114                 goto out;
9115         }
9116
9117         key.objectid = BTRFS_FIRST_FREE_OBJECTID;
9118         key.type = BTRFS_ROOT_ITEM_KEY;
9119         key.offset = 0;
9120
9121 again:
9122         /*
9123          * Avoid opening and committing transactions if a leaf doesn't have
9124          * any root items that need to be fixed, so that we avoid rotating
9125          * backup roots unnecessarily.
9126          */
9127         if (need_trans) {
9128                 trans = btrfs_start_transaction(info->tree_root, 1);
9129                 if (IS_ERR(trans)) {
9130                         ret = PTR_ERR(trans);
9131                         goto out;
9132                 }
9133         }
9134
9135         ret = btrfs_search_slot(trans, info->tree_root, &key, path,
9136                                 0, trans ? 1 : 0);
9137         if (ret < 0)
9138                 goto out;
9139         leaf = path->nodes[0];
9140
9141         while (1) {
9142                 struct btrfs_key found_key;
9143
9144                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
9145                         int no_more_keys = find_next_key(path, &key);
9146
9147                         btrfs_release_path(path);
9148                         if (trans) {
9149                                 ret = btrfs_commit_transaction(trans,
9150                                                                info->tree_root);
9151                                 trans = NULL;
9152                                 if (ret < 0)
9153                                         goto out;
9154                         }
9155                         need_trans = 0;
9156                         if (no_more_keys)
9157                                 break;
9158                         goto again;
9159                 }
9160
9161                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
9162
9163                 if (found_key.type != BTRFS_ROOT_ITEM_KEY)
9164                         goto next;
9165                 if (found_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
9166                         goto next;
9167
9168                 ret = maybe_repair_root_item(info, path, &found_key,
9169                                              trans ? 0 : 1);
9170                 if (ret < 0)
9171                         goto out;
9172                 if (ret) {
9173                         if (!trans && repair) {
9174                                 need_trans = 1;
9175                                 key = found_key;
9176                                 btrfs_release_path(path);
9177                                 goto again;
9178                         }
9179                         bad_roots++;
9180                 }
9181 next:
9182                 path->slots[0]++;
9183         }
9184         ret = 0;
9185 out:
9186         free_roots_info_cache();
9187         if (path)
9188                 btrfs_free_path(path);
9189         if (trans)
9190                 btrfs_commit_transaction(trans, info->tree_root);
9191         if (ret < 0)
9192                 return ret;
9193
9194         return bad_roots;
9195 }
9196
9197 const char * const cmd_check_usage[] = {
9198         "btrfs check [options] <device>",
9199         "Check an unmounted btrfs filesystem.",
9200         "",
9201         "-s|--super <superblock>     use this superblock copy",
9202         "-b|--backup                 use the backup root copy",
9203         "--repair                    try to repair the filesystem",
9204         "--init-csum-tree            create a new CRC tree",
9205         "--init-extent-tree          create a new extent tree",
9206         "--check-data-csum           verify checkums of data blocks",
9207         "--qgroup-report             print a report on qgroup consistency",
9208         "--subvol-extents <subvolid> print subvolume extents and sharing state",
9209         "--tree-root <bytenr>        use the given bytenr for the tree root",
9210         NULL
9211 };
9212
9213 int cmd_check(int argc, char **argv)
9214 {
9215         struct cache_tree root_cache;
9216         struct btrfs_root *root;
9217         struct btrfs_fs_info *info;
9218         u64 bytenr = 0;
9219         u64 subvolid = 0;
9220         u64 tree_root_bytenr = 0;
9221         char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
9222         int ret;
9223         u64 num;
9224         int init_csum_tree = 0;
9225         int readonly = 0;
9226         int qgroup_report = 0;
9227         enum btrfs_open_ctree_flags ctree_flags = OPEN_CTREE_EXCLUSIVE;
9228
9229         while(1) {
9230                 int c;
9231                 enum { OPT_REPAIR = 257, OPT_INIT_CSUM, OPT_INIT_EXTENT,
9232                         OPT_CHECK_CSUM, OPT_READONLY };
9233                 static const struct option long_options[] = {
9234                         { "super", required_argument, NULL, 's' },
9235                         { "repair", no_argument, NULL, OPT_REPAIR },
9236                         { "readonly", no_argument, NULL, OPT_READONLY },
9237                         { "init-csum-tree", no_argument, NULL, OPT_INIT_CSUM },
9238                         { "init-extent-tree", no_argument, NULL, OPT_INIT_EXTENT },
9239                         { "check-data-csum", no_argument, NULL, OPT_CHECK_CSUM },
9240                         { "backup", no_argument, NULL, 'b' },
9241                         { "subvol-extents", required_argument, NULL, 'E' },
9242                         { "qgroup-report", no_argument, NULL, 'Q' },
9243                         { "tree-root", required_argument, NULL, 'r' },
9244                         { NULL, 0, NULL, 0}
9245                 };
9246
9247                 c = getopt_long(argc, argv, "as:br:", long_options, NULL);
9248                 if (c < 0)
9249                         break;
9250                 switch(c) {
9251                         case 'a': /* ignored */ break;
9252                         case 'b':
9253                                 ctree_flags |= OPEN_CTREE_BACKUP_ROOT;
9254                                 break;
9255                         case 's':
9256                                 num = arg_strtou64(optarg);
9257                                 if (num >= BTRFS_SUPER_MIRROR_MAX) {
9258                                         fprintf(stderr,
9259                                                 "ERROR: super mirror should be less than: %d\n",
9260                                                 BTRFS_SUPER_MIRROR_MAX);
9261                                         exit(1);
9262                                 }
9263                                 bytenr = btrfs_sb_offset(((int)num));
9264                                 printf("using SB copy %llu, bytenr %llu\n", num,
9265                                        (unsigned long long)bytenr);
9266                                 break;
9267                         case 'Q':
9268                                 qgroup_report = 1;
9269                                 break;
9270                         case 'E':
9271                                 subvolid = arg_strtou64(optarg);
9272                                 break;
9273                         case 'r':
9274                                 tree_root_bytenr = arg_strtou64(optarg);
9275                                 break;
9276                         case '?':
9277                         case 'h':
9278                                 usage(cmd_check_usage);
9279                         case OPT_REPAIR:
9280                                 printf("enabling repair mode\n");
9281                                 repair = 1;
9282                                 ctree_flags |= OPEN_CTREE_WRITES;
9283                                 break;
9284                         case OPT_READONLY:
9285                                 readonly = 1;
9286                                 break;
9287                         case OPT_INIT_CSUM:
9288                                 printf("Creating a new CRC tree\n");
9289                                 init_csum_tree = 1;
9290                                 repair = 1;
9291                                 ctree_flags |= OPEN_CTREE_WRITES;
9292                                 break;
9293                         case OPT_INIT_EXTENT:
9294                                 init_extent_tree = 1;
9295                                 ctree_flags |= (OPEN_CTREE_WRITES |
9296                                                 OPEN_CTREE_NO_BLOCK_GROUPS);
9297                                 repair = 1;
9298                                 break;
9299                         case OPT_CHECK_CSUM:
9300                                 check_data_csum = 1;
9301                                 break;
9302                 }
9303         }
9304         argc = argc - optind;
9305
9306         if (check_argc_exact(argc, 1))
9307                 usage(cmd_check_usage);
9308
9309         /* This check is the only reason for --readonly to exist */
9310         if (readonly && repair) {
9311                 fprintf(stderr, "Repair options are not compatible with --readonly\n");
9312                 exit(1);
9313         }
9314
9315         radix_tree_init();
9316         cache_tree_init(&root_cache);
9317
9318         if((ret = check_mounted(argv[optind])) < 0) {
9319                 fprintf(stderr, "Could not check mount status: %s\n", strerror(-ret));
9320                 goto err_out;
9321         } else if(ret) {
9322                 fprintf(stderr, "%s is currently mounted. Aborting.\n", argv[optind]);
9323                 ret = -EBUSY;
9324                 goto err_out;
9325         }
9326
9327         /* only allow partial opening under repair mode */
9328         if (repair)
9329                 ctree_flags |= OPEN_CTREE_PARTIAL;
9330
9331         info = open_ctree_fs_info(argv[optind], bytenr, tree_root_bytenr,
9332                                   ctree_flags);
9333         if (!info) {
9334                 fprintf(stderr, "Couldn't open file system\n");
9335                 ret = -EIO;
9336                 goto err_out;
9337         }
9338
9339         root = info->fs_root;
9340
9341         /*
9342          * repair mode will force us to commit transaction which
9343          * will make us fail to load log tree when mounting.
9344          */
9345         if (repair && btrfs_super_log_root(info->super_copy)) {
9346                 ret = ask_user("repair mode will force to clear out log tree, Are you sure?");
9347                 if (!ret) {
9348                         ret = 1;
9349                         goto close_out;
9350                 }
9351                 ret = zero_log_tree(root);
9352                 if (ret) {
9353                         fprintf(stderr, "fail to zero log tree\n");
9354                         goto close_out;
9355                 }
9356         }
9357
9358         uuid_unparse(info->super_copy->fsid, uuidbuf);
9359         if (qgroup_report) {
9360                 printf("Print quota groups for %s\nUUID: %s\n", argv[optind],
9361                        uuidbuf);
9362                 ret = qgroup_verify_all(info);
9363                 if (ret == 0)
9364                         print_qgroup_report(1);
9365                 goto close_out;
9366         }
9367         if (subvolid) {
9368                 printf("Print extent state for subvolume %llu on %s\nUUID: %s\n",
9369                        subvolid, argv[optind], uuidbuf);
9370                 ret = print_extent_state(info, subvolid);
9371                 goto close_out;
9372         }
9373         printf("Checking filesystem on %s\nUUID: %s\n", argv[optind], uuidbuf);
9374
9375         if (!extent_buffer_uptodate(info->tree_root->node) ||
9376             !extent_buffer_uptodate(info->dev_root->node) ||
9377             !extent_buffer_uptodate(info->chunk_root->node)) {
9378                 fprintf(stderr, "Critical roots corrupted, unable to fsck the FS\n");
9379                 ret = -EIO;
9380                 goto close_out;
9381         }
9382
9383         if (init_extent_tree || init_csum_tree) {
9384                 struct btrfs_trans_handle *trans;
9385
9386                 trans = btrfs_start_transaction(info->extent_root, 0);
9387                 if (IS_ERR(trans)) {
9388                         fprintf(stderr, "Error starting transaction\n");
9389                         ret = PTR_ERR(trans);
9390                         goto close_out;
9391                 }
9392
9393                 if (init_extent_tree) {
9394                         printf("Creating a new extent tree\n");
9395                         ret = reinit_extent_tree(trans, info);
9396                         if (ret)
9397                                 goto close_out;
9398                 }
9399
9400                 if (init_csum_tree) {
9401                         fprintf(stderr, "Reinit crc root\n");
9402                         ret = btrfs_fsck_reinit_root(trans, info->csum_root, 0);
9403                         if (ret) {
9404                                 fprintf(stderr, "crc root initialization failed\n");
9405                                 ret = -EIO;
9406                                 goto close_out;
9407                         }
9408
9409                         ret = fill_csum_tree(trans, info->csum_root,
9410                                              init_extent_tree);
9411                         if (ret) {
9412                                 fprintf(stderr, "crc refilling failed\n");
9413                                 return -EIO;
9414                         }
9415                 }
9416                 /*
9417                  * Ok now we commit and run the normal fsck, which will add
9418                  * extent entries for all of the items it finds.
9419                  */
9420                 ret = btrfs_commit_transaction(trans, info->extent_root);
9421                 if (ret)
9422                         goto close_out;
9423         }
9424         if (!extent_buffer_uptodate(info->extent_root->node)) {
9425                 fprintf(stderr, "Critical roots corrupted, unable to fsck the FS\n");
9426                 ret = -EIO;
9427                 goto close_out;
9428         }
9429         if (!extent_buffer_uptodate(info->csum_root->node)) {
9430                 fprintf(stderr, "Checksum root corrupted, rerun with --init-csum-tree option\n");
9431                 ret = -EIO;
9432                 goto close_out;
9433         }
9434
9435         fprintf(stderr, "checking extents\n");
9436         ret = check_chunks_and_extents(root);
9437         if (ret)
9438                 fprintf(stderr, "Errors found in extent allocation tree or chunk allocation\n");
9439
9440         ret = repair_root_items(info);
9441         if (ret < 0)
9442                 goto close_out;
9443         if (repair) {
9444                 fprintf(stderr, "Fixed %d roots.\n", ret);
9445                 ret = 0;
9446         } else if (ret > 0) {
9447                 fprintf(stderr,
9448                        "Found %d roots with an outdated root item.\n",
9449                        ret);
9450                 fprintf(stderr,
9451                         "Please run a filesystem check with the option --repair to fix them.\n");
9452                 ret = 1;
9453                 goto close_out;
9454         }
9455
9456         fprintf(stderr, "checking free space cache\n");
9457         ret = check_space_cache(root);
9458         if (ret)
9459                 goto out;
9460
9461         /*
9462          * We used to have to have these hole extents in between our real
9463          * extents so if we don't have this flag set we need to make sure there
9464          * are no gaps in the file extents for inodes, otherwise we can just
9465          * ignore it when this happens.
9466          */
9467         no_holes = btrfs_fs_incompat(root->fs_info,
9468                                      BTRFS_FEATURE_INCOMPAT_NO_HOLES);
9469         fprintf(stderr, "checking fs roots\n");
9470         ret = check_fs_roots(root, &root_cache);
9471         if (ret)
9472                 goto out;
9473
9474         fprintf(stderr, "checking csums\n");
9475         ret = check_csums(root);
9476         if (ret)
9477                 goto out;
9478
9479         fprintf(stderr, "checking root refs\n");
9480         ret = check_root_refs(root, &root_cache);
9481         if (ret)
9482                 goto out;
9483
9484         while (repair && !list_empty(&root->fs_info->recow_ebs)) {
9485                 struct extent_buffer *eb;
9486
9487                 eb = list_first_entry(&root->fs_info->recow_ebs,
9488                                       struct extent_buffer, recow);
9489                 list_del_init(&eb->recow);
9490                 ret = recow_extent_buffer(root, eb);
9491                 if (ret)
9492                         break;
9493         }
9494
9495         while (!list_empty(&delete_items)) {
9496                 struct bad_item *bad;
9497
9498                 bad = list_first_entry(&delete_items, struct bad_item, list);
9499                 list_del_init(&bad->list);
9500                 if (repair)
9501                         ret = delete_bad_item(root, bad);
9502                 free(bad);
9503         }
9504
9505         if (info->quota_enabled) {
9506                 int err;
9507                 fprintf(stderr, "checking quota groups\n");
9508                 err = qgroup_verify_all(info);
9509                 if (err)
9510                         goto out;
9511         }
9512
9513         if (!list_empty(&root->fs_info->recow_ebs)) {
9514                 fprintf(stderr, "Transid errors in file system\n");
9515                 ret = 1;
9516         }
9517 out:
9518         print_qgroup_report(0);
9519         if (found_old_backref) { /*
9520                  * there was a disk format change when mixed
9521                  * backref was in testing tree. The old format
9522                  * existed about one week.
9523                  */
9524                 printf("\n * Found old mixed backref format. "
9525                        "The old format is not supported! *"
9526                        "\n * Please mount the FS in readonly mode, "
9527                        "backup data and re-format the FS. *\n\n");
9528                 ret = 1;
9529         }
9530         printf("found %llu bytes used err is %d\n",
9531                (unsigned long long)bytes_used, ret);
9532         printf("total csum bytes: %llu\n",(unsigned long long)total_csum_bytes);
9533         printf("total tree bytes: %llu\n",
9534                (unsigned long long)total_btree_bytes);
9535         printf("total fs tree bytes: %llu\n",
9536                (unsigned long long)total_fs_tree_bytes);
9537         printf("total extent tree bytes: %llu\n",
9538                (unsigned long long)total_extent_tree_bytes);
9539         printf("btree space waste bytes: %llu\n",
9540                (unsigned long long)btree_space_waste);
9541         printf("file data blocks allocated: %llu\n referenced %llu\n",
9542                 (unsigned long long)data_bytes_allocated,
9543                 (unsigned long long)data_bytes_referenced);
9544         printf("%s\n", PACKAGE_STRING);
9545
9546         free_root_recs_tree(&root_cache);
9547 close_out:
9548         close_ctree(root);
9549 err_out:
9550         return ret;
9551 }