btrfsck.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 #define _XOPEN_SOURCE 500
  20 #define _GNU_SOURCE 1
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <fcntl.h>
  25 #include <sys/stat.h>
  26 #include <getopt.h>
  27 #include "kerncompat.h"
  28 #include "ctree.h"
  29 #include "disk-io.h"
  30 #include "print-tree.h"
  31 #include "transaction.h"
  32 #include "list.h"
  33 #include "version.h"
  34 #include "utils.h"
  35
  36 static u64 bytes_used = 0;
  37 static u64 total_csum_bytes = 0;
  38 static u64 total_btree_bytes = 0;
  39 static u64 total_fs_tree_bytes = 0;
  40 static u64 btree_space_waste = 0;
  41 static u64 data_bytes_allocated = 0;
  42 static u64 data_bytes_referenced = 0;
  43 static int found_old_backref = 0;
  44
  45 struct extent_backref {
  46         struct list_head list;
  47         unsigned int is_data:1;
  48         unsigned int found_extent_tree:1;
  49         unsigned int full_backref:1;
  50         unsigned int found_ref:1;
  51 };
  52
  53 struct data_backref {
  54         struct extent_backref node;
  55         union {
  56                 u64 parent;
  57                 u64 root;
  58         };
  59         u64 owner;
  60         u64 offset;
  61         u32 num_refs;
  62         u32 found_ref;
  63 };
  64
  65 struct tree_backref {
  66         struct extent_backref node;
  67         union {
  68                 u64 parent;
  69                 u64 root;
  70         };
  71 };
  72
  73 struct extent_record {
  74         struct list_head backrefs;
  75         struct cache_extent cache;
  76         struct btrfs_disk_key parent_key;
  77         u64 start;
  78         u64 max_size;
  79         u64 nr;
  80         u64 refs;
  81         u64 extent_item_refs;
  82         u64 generation;
  83         u64 info_objectid;
  84         u8 info_level;
  85         unsigned int content_checked:1;
  86         unsigned int owner_ref_checked:1;
  87         unsigned int is_root:1;
  88 };
  89
  90 struct inode_backref {
  91         struct list_head list;
  92         unsigned int found_dir_item:1;
  93         unsigned int found_dir_index:1;
  94         unsigned int found_inode_ref:1;
  95         unsigned int filetype:8;
  96         int errors;
  97         u64 dir;
  98         u64 index;
  99         u16 namelen;
 100         char name[0];
 101 };
 102
 103 #define REF_ERR_NO_DIR_ITEM             (1 << 0)
 104 #define REF_ERR_NO_DIR_INDEX            (1 << 1)
 105 #define REF_ERR_NO_INODE_REF            (1 << 2)
 106 #define REF_ERR_DUP_DIR_ITEM            (1 << 3)
 107 #define REF_ERR_DUP_DIR_INDEX           (1 << 4)
 108 #define REF_ERR_DUP_INODE_REF           (1 << 5)
 109 #define REF_ERR_INDEX_UNMATCH           (1 << 6)
 110 #define REF_ERR_FILETYPE_UNMATCH        (1 << 7)
 111 #define REF_ERR_NAME_TOO_LONG           (1 << 8) // 100
 112 #define REF_ERR_NO_ROOT_REF             (1 << 9)
 113 #define REF_ERR_NO_ROOT_BACKREF         (1 << 10)
 114 #define REF_ERR_DUP_ROOT_REF            (1 << 11)
 115 #define REF_ERR_DUP_ROOT_BACKREF        (1 << 12)
 116
 117 struct inode_record {
 118         struct list_head backrefs;
 119         unsigned int checked:1;
 120         unsigned int merging:1;
 121         unsigned int found_inode_item:1;
 122         unsigned int found_dir_item:1;
 123         unsigned int found_file_extent:1;
 124         unsigned int found_csum_item:1;
 125         unsigned int some_csum_missing:1;
 126         unsigned int nodatasum:1;
 127         int errors;
 128
 129         u64 ino;
 130         u32 nlink;
 131         u32 imode;
 132         u64 isize;
 133         u64 nbytes;
 134
 135         u32 found_link;
 136         u64 found_size;
 137         u64 extent_start;
 138         u64 extent_end;
 139         u64 first_extent_gap;
 140
 141         u32 refs;
 142 };
 143
 144 #define I_ERR_NO_INODE_ITEM             (1 << 0)
 145 #define I_ERR_NO_ORPHAN_ITEM            (1 << 1)
 146 #define I_ERR_DUP_INODE_ITEM            (1 << 2)
 147 #define I_ERR_DUP_DIR_INDEX             (1 << 3)
 148 #define I_ERR_ODD_DIR_ITEM              (1 << 4)
 149 #define I_ERR_ODD_FILE_EXTENT           (1 << 5)
 150 #define I_ERR_BAD_FILE_EXTENT           (1 << 6)
 151 #define I_ERR_FILE_EXTENT_OVERLAP       (1 << 7)
 152 #define I_ERR_FILE_EXTENT_DISCOUNT      (1 << 8) // 100
 153 #define I_ERR_DIR_ISIZE_WRONG           (1 << 9)
 154 #define I_ERR_FILE_NBYTES_WRONG         (1 << 10) // 400
 155 #define I_ERR_ODD_CSUM_ITEM             (1 << 11)
 156 #define I_ERR_SOME_CSUM_MISSING         (1 << 12)
 157 #define I_ERR_LINK_COUNT_WRONG          (1 << 13)
 158
 159 struct root_backref {
 160         struct list_head list;
 161         unsigned int found_dir_item:1;
 162         unsigned int found_dir_index:1;
 163         unsigned int found_back_ref:1;
 164         unsigned int found_forward_ref:1;
 165         unsigned int reachable:1;
 166         int errors;
 167         u64 ref_root;
 168         u64 dir;
 169         u64 index;
 170         u16 namelen;
 171         char name[0];
 172 };
 173
 174 struct root_record {
 175         struct list_head backrefs;
 176         struct cache_extent cache;
 177         unsigned int found_root_item:1;
 178         u64 objectid;
 179         u32 found_ref;
 180 };
 181
 182 struct ptr_node {
 183         struct cache_extent cache;
 184         void *data;
 185 };
 186
 187 struct shared_node {
 188         struct cache_extent cache;
 189         struct cache_tree root_cache;
 190         struct cache_tree inode_cache;
 191         struct inode_record *current;
 192         u32 refs;
 193 };
 194
 195 struct block_info {
 196         u64 start;
 197         u32 size;
 198 };
 199
 200 struct walk_control {
 201         struct cache_tree shared;
 202         struct shared_node *nodes[BTRFS_MAX_LEVEL];
 203         int active_node;
 204         int root_level;
 205 };
 206
 207 static u8 imode_to_type(u32 imode)
 208 {
 209 #define S_SHIFT 12
 210         static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
 211                 [S_IFREG >> S_SHIFT]    = BTRFS_FT_REG_FILE,
 212                 [S_IFDIR >> S_SHIFT]    = BTRFS_FT_DIR,
 213                 [S_IFCHR >> S_SHIFT]    = BTRFS_FT_CHRDEV,
 214                 [S_IFBLK >> S_SHIFT]    = BTRFS_FT_BLKDEV,
 215                 [S_IFIFO >> S_SHIFT]    = BTRFS_FT_FIFO,
 216                 [S_IFSOCK >> S_SHIFT]   = BTRFS_FT_SOCK,
 217                 [S_IFLNK >> S_SHIFT]    = BTRFS_FT_SYMLINK,
 218         };
 219
 220         return btrfs_type_by_mode[(imode & S_IFMT) >> S_SHIFT];
 221 #undef S_SHIFT
 222 }
 223
 224 static struct inode_record *clone_inode_rec(struct inode_record *orig_rec)
 225 {
 226         struct inode_record *rec;
 227         struct inode_backref *backref;
 228         struct inode_backref *orig;
 229         size_t size;
 230
 231         rec = malloc(sizeof(*rec));
 232         memcpy(rec, orig_rec, sizeof(*rec));
 233         rec->refs = 1;
 234         INIT_LIST_HEAD(&rec->backrefs);
 235
 236         list_for_each_entry(orig, &orig_rec->backrefs, list) {
 237                 size = sizeof(*orig) + orig->namelen + 1;
 238                 backref = malloc(size);
 239                 memcpy(backref, orig, size);
 240                 list_add_tail(&backref->list, &rec->backrefs);
 241         }
 242         return rec;
 243 }
 244
 245 static struct inode_record *get_inode_rec(struct cache_tree *inode_cache,
 246                                           u64 ino, int mod)
 247 {
 248         struct ptr_node *node;
 249         struct cache_extent *cache;
 250         struct inode_record *rec = NULL;
 251         int ret;
 252
 253         cache = find_cache_extent(inode_cache, ino, 1);
 254         if (cache) {
 255                 node = container_of(cache, struct ptr_node, cache);
 256                 rec = node->data;
 257                 if (mod && rec->refs > 1) {
 258                         node->data = clone_inode_rec(rec);
 259                         rec->refs--;
 260                         rec = node->data;
 261                 }
 262         } else if (mod) {
 263                 rec = calloc(1, sizeof(*rec));
 264                 rec->ino = ino;
 265                 rec->extent_start = (u64)-1;
 266                 rec->first_extent_gap = (u64)-1;
 267                 rec->refs = 1;
 268                 INIT_LIST_HEAD(&rec->backrefs);
 269
 270                 node = malloc(sizeof(*node));
 271                 node->cache.start = ino;
 272                 node->cache.size = 1;
 273                 node->data = rec;
 274
 275                 ret = insert_existing_cache_extent(inode_cache, &node->cache);
 276                 BUG_ON(ret);
 277         }
 278         return rec;
 279 }
 280
 281 static void free_inode_rec(struct inode_record *rec)
 282 {
 283         struct inode_backref *backref;
 284
 285         if (--rec->refs > 0)
 286                 return;
 287
 288         while (!list_empty(&rec->backrefs)) {
 289                 backref = list_entry(rec->backrefs.next,
 290                                      struct inode_backref, list);
 291                 list_del(&backref->list);
 292                 free(backref);
 293         }
 294         free(rec);
 295 }
 296
 297 static int can_free_inode_rec(struct inode_record *rec)
 298 {
 299         if (!rec->errors && rec->checked && rec->found_inode_item &&
 300             rec->nlink == rec->found_link && list_empty(&rec->backrefs))
 301                 return 1;
 302         return 0;
 303 }
 304
 305 static void maybe_free_inode_rec(struct cache_tree *inode_cache,
 306                                  struct inode_record *rec)
 307 {
 308         struct cache_extent *cache;
 309         struct inode_backref *tmp, *backref;
 310         struct ptr_node *node;
 311         unsigned char filetype;
 312
 313         if (!rec->found_inode_item)
 314                 return;
 315
 316         filetype = imode_to_type(rec->imode);
 317         list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
 318                 if (backref->found_dir_item && backref->found_dir_index) {
 319                         if (backref->filetype != filetype)
 320                                 backref->errors |= REF_ERR_FILETYPE_UNMATCH;
 321                         if (!backref->errors && backref->found_inode_ref) {
 322                                 list_del(&backref->list);
 323                                 free(backref);
 324                         }
 325                 }
 326         }
 327
 328         if (!rec->checked || rec->merging)
 329                 return;
 330
 331         if (S_ISDIR(rec->imode)) {
 332                 if (rec->found_size != rec->isize)
 333                         rec->errors |= I_ERR_DIR_ISIZE_WRONG;
 334                 if (rec->found_file_extent)
 335                         rec->errors |= I_ERR_ODD_FILE_EXTENT;
 336         } else if (S_ISREG(rec->imode) || S_ISLNK(rec->imode)) {
 337                 if (rec->found_dir_item)
 338                         rec->errors |= I_ERR_ODD_DIR_ITEM;
 339                 if (rec->found_size != rec->nbytes)
 340                         rec->errors |= I_ERR_FILE_NBYTES_WRONG;
 341                 if (rec->extent_start == (u64)-1 || rec->extent_start > 0)
 342                         rec->first_extent_gap = 0;
 343                 if (rec->nlink > 0 && (rec->extent_end < rec->isize ||
 344                     rec->first_extent_gap < rec->isize))
 345                         rec->errors |= I_ERR_FILE_EXTENT_DISCOUNT;
 346         }
 347
 348         if (S_ISREG(rec->imode) || S_ISLNK(rec->imode)) {
 349                 if (rec->found_csum_item && rec->nodatasum)
 350                         rec->errors |= I_ERR_ODD_CSUM_ITEM;
 351                 if (rec->some_csum_missing && !rec->nodatasum)
 352                         rec->errors |= I_ERR_SOME_CSUM_MISSING;
 353         }
 354
 355         BUG_ON(rec->refs != 1);
 356         if (can_free_inode_rec(rec)) {
 357                 cache = find_cache_extent(inode_cache, rec->ino, 1);
 358                 node = container_of(cache, struct ptr_node, cache);
 359                 BUG_ON(node->data != rec);
 360                 remove_cache_extent(inode_cache, &node->cache);
 361                 free(node);
 362                 free_inode_rec(rec);
 363         }
 364 }
 365
 366 static int check_orphan_item(struct btrfs_root *root, u64 ino)
 367 {
 368         struct btrfs_path path;
 369         struct btrfs_key key;
 370         int ret;
 371
 372         key.objectid = BTRFS_ORPHAN_OBJECTID;
 373         key.type = BTRFS_ORPHAN_ITEM_KEY;
 374         key.offset = ino;
 375
 376         btrfs_init_path(&path);
 377         ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
 378         btrfs_release_path(root, &path);
 379         if (ret > 0)
 380                 ret = -ENOENT;
 381         return ret;
 382 }
 383
 384 static int process_inode_item(struct extent_buffer *eb,
 385                               int slot, struct btrfs_key *key,
 386                               struct shared_node *active_node)
 387 {
 388         struct inode_record *rec;
 389         struct btrfs_inode_item *item;
 390
 391         rec = active_node->current;
 392         BUG_ON(rec->ino != key->objectid || rec->refs > 1);
 393         if (rec->found_inode_item) {
 394                 rec->errors |= I_ERR_DUP_INODE_ITEM;
 395                 return 1;
 396         }
 397         item = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
 398         rec->nlink = btrfs_inode_nlink(eb, item);
 399         rec->isize = btrfs_inode_size(eb, item);
 400         rec->nbytes = btrfs_inode_nbytes(eb, item);
 401         rec->imode = btrfs_inode_mode(eb, item);
 402         if (btrfs_inode_flags(eb, item) & BTRFS_INODE_NODATASUM)
 403                 rec->nodatasum = 1;
 404         rec->found_inode_item = 1;
 405         if (rec->nlink == 0)
 406                 rec->errors |= I_ERR_NO_ORPHAN_ITEM;
 407         maybe_free_inode_rec(&active_node->inode_cache, rec);
 408         return 0;
 409 }
 410
 411 static struct inode_backref *get_inode_backref(struct inode_record *rec,
 412                                                 const char *name,
 413                                                 int namelen, u64 dir)
 414 {
 415         struct inode_backref *backref;
 416
 417         list_for_each_entry(backref, &rec->backrefs, list) {
 418                 if (backref->dir != dir || backref->namelen != namelen)
 419                         continue;
 420                 if (memcmp(name, backref->name, namelen))
 421                         continue;
 422                 return backref;
 423         }
 424
 425         backref = malloc(sizeof(*backref) + namelen + 1);
 426         memset(backref, 0, sizeof(*backref));
 427         backref->dir = dir;
 428         backref->namelen = namelen;
 429         memcpy(backref->name, name, namelen);
 430         backref->name[namelen] = '\0';
 431         list_add_tail(&backref->list, &rec->backrefs);
 432         return backref;
 433 }
 434
 435 static int add_inode_backref(struct cache_tree *inode_cache,
 436                              u64 ino, u64 dir, u64 index,
 437                              const char *name, int namelen,
 438                              int filetype, int itemtype, int errors)
 439 {
 440         struct inode_record *rec;
 441         struct inode_backref *backref;
 442
 443         rec = get_inode_rec(inode_cache, ino, 1);
 444         backref = get_inode_backref(rec, name, namelen, dir);
 445         if (errors)
 446                 backref->errors |= errors;
 447         if (itemtype == BTRFS_DIR_INDEX_KEY) {
 448                 if (backref->found_dir_index)
 449                         backref->errors |= REF_ERR_DUP_DIR_INDEX;
 450                 if (backref->found_inode_ref && backref->index != index)
 451                         backref->errors |= REF_ERR_INDEX_UNMATCH;
 452                 if (backref->found_dir_item && backref->filetype != filetype)
 453                         backref->errors |= REF_ERR_FILETYPE_UNMATCH;
 454
 455                 backref->index = index;
 456                 backref->filetype = filetype;
 457                 backref->found_dir_index = 1;
 458         } else if (itemtype == BTRFS_DIR_ITEM_KEY) {
 459                 rec->found_link++;
 460                 if (backref->found_dir_item)
 461                         backref->errors |= REF_ERR_DUP_DIR_ITEM;
 462                 if (backref->found_dir_index && backref->filetype != filetype)
 463                         backref->errors |= REF_ERR_FILETYPE_UNMATCH;
 464
 465                 backref->filetype = filetype;
 466                 backref->found_dir_item = 1;
 467         } else if (itemtype == BTRFS_INODE_REF_KEY) {
 468                 if (backref->found_inode_ref)
 469                         backref->errors |= REF_ERR_DUP_INODE_REF;
 470                 if (backref->found_dir_index && backref->index != index)
 471                         backref->errors |= REF_ERR_INDEX_UNMATCH;
 472
 473                 backref->index = index;
 474                 backref->found_inode_ref = 1;
 475         } else {
 476                 BUG_ON(1);
 477         }
 478
 479         maybe_free_inode_rec(inode_cache, rec);
 480         return 0;
 481 }
 482
 483 static int merge_inode_recs(struct inode_record *src, struct inode_record *dst,
 484                             struct cache_tree *dst_cache)
 485 {
 486         struct inode_backref *backref;
 487         u32 dir_count = 0;
 488
 489         dst->merging = 1;
 490         list_for_each_entry(backref, &src->backrefs, list) {
 491                 if (backref->found_dir_index) {
 492                         add_inode_backref(dst_cache, dst->ino, backref->dir,
 493                                         backref->index, backref->name,
 494                                         backref->namelen, backref->filetype,
 495                                         BTRFS_DIR_INDEX_KEY, backref->errors);
 496                 }
 497                 if (backref->found_dir_item) {
 498                         dir_count++;
 499                         add_inode_backref(dst_cache, dst->ino,
 500                                         backref->dir, 0, backref->name,
 501                                         backref->namelen, backref->filetype,
 502                                         BTRFS_DIR_ITEM_KEY, backref->errors);
 503                 }
 504                 if (backref->found_inode_ref) {
 505                         add_inode_backref(dst_cache, dst->ino,
 506                                         backref->dir, backref->index,
 507                                         backref->name, backref->namelen, 0,
 508                                         BTRFS_INODE_REF_KEY, backref->errors);
 509                 }
 510         }
 511
 512         if (src->found_dir_item)
 513                 dst->found_dir_item = 1;
 514         if (src->found_file_extent)
 515                 dst->found_file_extent = 1;
 516         if (src->found_csum_item)
 517                 dst->found_csum_item = 1;
 518         if (src->some_csum_missing)
 519                 dst->some_csum_missing = 1;
 520         if (dst->first_extent_gap > src->first_extent_gap)
 521                 dst->first_extent_gap = src->first_extent_gap;
 522
 523         BUG_ON(src->found_link < dir_count);
 524         dst->found_link += src->found_link - dir_count;
 525         dst->found_size += src->found_size;
 526         if (src->extent_start != (u64)-1) {
 527                 if (dst->extent_start == (u64)-1) {
 528                         dst->extent_start = src->extent_start;
 529                         dst->extent_end = src->extent_end;
 530                 } else {
 531                         if (dst->extent_end > src->extent_start)
 532                                 dst->errors |= I_ERR_FILE_EXTENT_OVERLAP;
 533                         else if (dst->extent_end < src->extent_start &&
 534                                  dst->extent_end < dst->first_extent_gap)
 535                                 dst->first_extent_gap = dst->extent_end;
 536                         if (dst->extent_end < src->extent_end)
 537                                 dst->extent_end = src->extent_end;
 538                 }
 539         }
 540
 541         dst->errors |= src->errors;
 542         if (src->found_inode_item) {
 543                 if (!dst->found_inode_item) {
 544                         dst->nlink = src->nlink;
 545                         dst->isize = src->isize;
 546                         dst->nbytes = src->nbytes;
 547                         dst->imode = src->imode;
 548                         dst->nodatasum = src->nodatasum;
 549                         dst->found_inode_item = 1;
 550                 } else {
 551                         dst->errors |= I_ERR_DUP_INODE_ITEM;
 552                 }
 553         }
 554         dst->merging = 0;
 555
 556         return 0;
 557 }
 558
 559 static int splice_shared_node(struct shared_node *src_node,
 560                               struct shared_node *dst_node)
 561 {
 562         struct cache_extent *cache;
 563         struct ptr_node *node, *ins;
 564         struct cache_tree *src, *dst;
 565         struct inode_record *rec, *conflict;
 566         u64 current_ino = 0;
 567         int splice = 0;
 568         int ret;
 569
 570         if (--src_node->refs == 0)
 571                 splice = 1;
 572         if (src_node->current)
 573                 current_ino = src_node->current->ino;
 574
 575         src = &src_node->root_cache;
 576         dst = &dst_node->root_cache;
 577 again:
 578         cache = find_first_cache_extent(src, 0);
 579         while (cache) {
 580                 node = container_of(cache, struct ptr_node, cache);
 581                 rec = node->data;
 582                 cache = next_cache_extent(cache);
 583
 584                 if (splice) {
 585                         remove_cache_extent(src, &node->cache);
 586                         ins = node;
 587                 } else {
 588                         ins = malloc(sizeof(*ins));
 589                         ins->cache.start = node->cache.start;
 590                         ins->cache.size = node->cache.size;
 591                         ins->data = rec;
 592                         rec->refs++;
 593                 }
 594                 ret = insert_existing_cache_extent(dst, &ins->cache);
 595                 if (ret == -EEXIST) {
 596                         conflict = get_inode_rec(dst, rec->ino, 1);
 597                         merge_inode_recs(rec, conflict, dst);
 598                         if (rec->checked) {
 599                                 conflict->checked = 1;
 600                                 if (dst_node->current == conflict)
 601                                         dst_node->current = NULL;
 602                         }
 603                         maybe_free_inode_rec(dst, conflict);
 604                         free_inode_rec(rec);
 605                         free(ins);
 606                 } else {
 607                         BUG_ON(ret);
 608                 }
 609         }
 610
 611         if (src == &src_node->root_cache) {
 612                 src = &src_node->inode_cache;
 613                 dst = &dst_node->inode_cache;
 614                 goto again;
 615         }
 616
 617         if (current_ino > 0 && (!dst_node->current ||
 618             current_ino > dst_node->current->ino)) {
 619                 if (dst_node->current) {
 620                         dst_node->current->checked = 1;
 621                         maybe_free_inode_rec(dst, dst_node->current);
 622                 }
 623                 dst_node->current = get_inode_rec(dst, current_ino, 1);
 624         }
 625         return 0;
 626 }
 627
 628 static void free_inode_recs(struct cache_tree *inode_cache)
 629 {
 630         struct cache_extent *cache;
 631         struct ptr_node *node;
 632         struct inode_record *rec;
 633
 634         while (1) {
 635                 cache = find_first_cache_extent(inode_cache, 0);
 636                 if (!cache)
 637                         break;
 638                 node = container_of(cache, struct ptr_node, cache);
 639                 rec = node->data;
 640                 remove_cache_extent(inode_cache, &node->cache);
 641                 free(node);
 642                 free_inode_rec(rec);
 643         }
 644 }
 645
 646 static struct shared_node *find_shared_node(struct cache_tree *shared,
 647                                             u64 bytenr)
 648 {
 649         struct cache_extent *cache;
 650         struct shared_node *node;
 651
 652         cache = find_cache_extent(shared, bytenr, 1);
 653         if (cache) {
 654                 node = container_of(cache, struct shared_node, cache);
 655                 return node;
 656         }
 657         return NULL;
 658 }
 659
 660 static int add_shared_node(struct cache_tree *shared, u64 bytenr, u32 refs)
 661 {
 662         int ret;
 663         struct shared_node *node;
 664
 665         node = calloc(1, sizeof(*node));
 666         node->cache.start = bytenr;
 667         node->cache.size = 1;
 668         cache_tree_init(&node->root_cache);
 669         cache_tree_init(&node->inode_cache);
 670         node->refs = refs;
 671
 672         ret = insert_existing_cache_extent(shared, &node->cache);
 673         BUG_ON(ret);
 674         return 0;
 675 }
 676
 677 static int enter_shared_node(struct btrfs_root *root, u64 bytenr, u32 refs,
 678                              struct walk_control *wc, int level)
 679 {
 680         struct shared_node *node;
 681         struct shared_node *dest;
 682
 683         if (level == wc->active_node)
 684                 return 0;
 685
 686         BUG_ON(wc->active_node <= level);
 687         node = find_shared_node(&wc->shared, bytenr);
 688         if (!node) {
 689                 add_shared_node(&wc->shared, bytenr, refs);
 690                 node = find_shared_node(&wc->shared, bytenr);
 691                 wc->nodes[level] = node;
 692                 wc->active_node = level;
 693                 return 0;
 694         }
 695
 696         if (wc->root_level == wc->active_node &&
 697             btrfs_root_refs(&root->root_item) == 0) {
 698                 if (--node->refs == 0) {
 699                         free_inode_recs(&node->root_cache);
 700                         free_inode_recs(&node->inode_cache);
 701                         remove_cache_extent(&wc->shared, &node->cache);
 702                         free(node);
 703                 }
 704                 return 1;
 705         }
 706
 707         dest = wc->nodes[wc->active_node];
 708         splice_shared_node(node, dest);
 709         if (node->refs == 0) {
 710                 remove_cache_extent(&wc->shared, &node->cache);
 711                 free(node);
 712         }
 713         return 1;
 714 }
 715
 716 static int leave_shared_node(struct btrfs_root *root,
 717                              struct walk_control *wc, int level)
 718 {
 719         struct shared_node *node;
 720         struct shared_node *dest;
 721         int i;
 722
 723         if (level == wc->root_level)
 724                 return 0;
 725
 726         for (i = level + 1; i < BTRFS_MAX_LEVEL; i++) {
 727                 if (wc->nodes[i])
 728                         break;
 729         }
 730         BUG_ON(i >= BTRFS_MAX_LEVEL);
 731
 732         node = wc->nodes[wc->active_node];
 733         wc->nodes[wc->active_node] = NULL;
 734         wc->active_node = i;
 735
 736         dest = wc->nodes[wc->active_node];
 737         if (wc->active_node < wc->root_level ||
 738             btrfs_root_refs(&root->root_item) > 0) {
 739                 BUG_ON(node->refs <= 1);
 740                 splice_shared_node(node, dest);
 741         } else {
 742                 BUG_ON(node->refs < 2);
 743                 node->refs--;
 744         }
 745         return 0;
 746 }
 747
 748 static int process_dir_item(struct extent_buffer *eb,
 749                             int slot, struct btrfs_key *key,
 750                             struct shared_node *active_node)
 751 {
 752         u32 total;
 753         u32 cur = 0;
 754         u32 len;
 755         u32 name_len;
 756         u32 data_len;
 757         int error;
 758         int nritems = 0;
 759         int filetype;
 760         struct btrfs_dir_item *di;
 761         struct inode_record *rec;
 762         struct cache_tree *root_cache;
 763         struct cache_tree *inode_cache;
 764         struct btrfs_key location;
 765         char namebuf[BTRFS_NAME_LEN];
 766
 767         root_cache = &active_node->root_cache;
 768         inode_cache = &active_node->inode_cache;
 769         rec = active_node->current;
 770         rec->found_dir_item = 1;
 771
 772         di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
 773         total = btrfs_item_size_nr(eb, slot);
 774         while (cur < total) {
 775                 nritems++;
 776                 btrfs_dir_item_key_to_cpu(eb, di, &location);
 777                 name_len = btrfs_dir_name_len(eb, di);
 778                 data_len = btrfs_dir_data_len(eb, di);
 779                 filetype = btrfs_dir_type(eb, di);
 780
 781                 rec->found_size += name_len;
 782                 if (name_len <= BTRFS_NAME_LEN) {
 783                         len = name_len;
 784                         error = 0;
 785                 } else {
 786                         len = BTRFS_NAME_LEN;
 787                         error = REF_ERR_NAME_TOO_LONG;
 788                 }
 789                 read_extent_buffer(eb, namebuf, (unsigned long)(di + 1), len);
 790
 791                 if (location.type == BTRFS_INODE_ITEM_KEY) {
 792                         add_inode_backref(inode_cache, location.objectid,
 793                                           key->objectid, key->offset, namebuf,
 794                                           len, filetype, key->type, error);
 795                 } else if (location.type == BTRFS_ROOT_ITEM_KEY) {
 796                         add_inode_backref(root_cache, location.objectid,
 797                                           key->objectid, key->offset, namebuf,
 798                                           len, filetype, key->type, error);
 799                 } else {
 800                         fprintf(stderr, "warning line %d\n", __LINE__);
 801                 }
 802
 803                 len = sizeof(*di) + name_len + data_len;
 804                 di = (struct btrfs_dir_item *)((char *)di + len);
 805                 cur += len;
 806         }
 807         if (key->type == BTRFS_DIR_INDEX_KEY && nritems > 1)
 808                 rec->errors |= I_ERR_DUP_DIR_INDEX;
 809
 810         return 0;
 811 }
 812
 813 static int process_inode_ref(struct extent_buffer *eb,
 814                              int slot, struct btrfs_key *key,
 815                              struct shared_node *active_node)
 816 {
 817         u32 total;
 818         u32 cur = 0;
 819         u32 len;
 820         u32 name_len;
 821         u64 index;
 822         int error;
 823         struct cache_tree *inode_cache;
 824         struct btrfs_inode_ref *ref;
 825         char namebuf[BTRFS_NAME_LEN];
 826
 827         inode_cache = &active_node->inode_cache;
 828
 829         ref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref);
 830         total = btrfs_item_size_nr(eb, slot);
 831         while (cur < total) {
 832                 name_len = btrfs_inode_ref_name_len(eb, ref);
 833                 index = btrfs_inode_ref_index(eb, ref);
 834                 if (name_len <= BTRFS_NAME_LEN) {
 835                         len = name_len;
 836                         error = 0;
 837                 } else {
 838                         len = BTRFS_NAME_LEN;
 839                         error = REF_ERR_NAME_TOO_LONG;
 840                 }
 841                 read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
 842                 add_inode_backref(inode_cache, key->objectid, key->offset,
 843                                   index, namebuf, len, 0, key->type, error);
 844
 845                 len = sizeof(*ref) + name_len;
 846                 ref = (struct btrfs_inode_ref *)((char *)ref + len);
 847                 cur += len;
 848         }
 849         return 0;
 850 }
 851
 852 static u64 count_csum_range(struct btrfs_root *root, u64 start, u64 len)
 853 {
 854         struct btrfs_key key;
 855         struct btrfs_path path;
 856         struct extent_buffer *leaf;
 857         int ret ;
 858         size_t size;
 859         u64 found = 0;
 860         u64 csum_end;
 861         u16 csum_size = btrfs_super_csum_size(&root->fs_info->super_copy);
 862
 863         btrfs_init_path(&path);
 864
 865         key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
 866         key.offset = start;
 867         key.type = BTRFS_EXTENT_CSUM_KEY;
 868
 869         ret = btrfs_search_slot(NULL, root->fs_info->csum_root,
 870                                 &key, &path, 0, 0);
 871         BUG_ON(ret < 0);
 872         if (ret > 0 && path.slots[0] > 0) {
 873                 leaf = path.nodes[0];
 874                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0] - 1);
 875                 if (key.objectid == BTRFS_EXTENT_CSUM_OBJECTID &&
 876                     key.type == BTRFS_EXTENT_CSUM_KEY)
 877                         path.slots[0]--;
 878         }
 879
 880         while (len > 0) {
 881                 leaf = path.nodes[0];
 882                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
 883                         ret = btrfs_next_leaf(root->fs_info->csum_root, &path);
 884                         BUG_ON(ret < 0);
 885                         if (ret > 0)
 886                                 break;
 887                         leaf = path.nodes[0];
 888                 }
 889
 890                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
 891                 if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
 892                     key.type != BTRFS_EXTENT_CSUM_KEY)
 893                         break;
 894
 895                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
 896                 if (key.offset >= start + len)
 897                         break;
 898
 899                 if (key.offset > start)
 900                         start = key.offset;
 901
 902                 size = btrfs_item_size_nr(leaf, path.slots[0]);
 903                 csum_end = key.offset + (size / csum_size) * root->sectorsize;
 904                 if (csum_end > start) {
 905                         size = min(csum_end - start, len);
 906                         len -= size;
 907                         start += size;
 908                         found += size;
 909                 }
 910
 911                 path.slots[0]++;
 912         }
 913         btrfs_release_path(root->fs_info->csum_root, &path);
 914         return found;
 915 }
 916
 917 static int process_file_extent(struct btrfs_root *root,
 918                                 struct extent_buffer *eb,
 919                                 int slot, struct btrfs_key *key,
 920                                 struct shared_node *active_node)
 921 {
 922         struct inode_record *rec;
 923         struct btrfs_file_extent_item *fi;
 924         u64 num_bytes = 0;
 925         u64 disk_bytenr = 0;
 926         u64 extent_offset = 0;
 927         u64 mask = root->sectorsize - 1;
 928         int extent_type;
 929
 930         rec = active_node->current;
 931         BUG_ON(rec->ino != key->objectid || rec->refs > 1);
 932         rec->found_file_extent = 1;
 933
 934         if (rec->extent_start == (u64)-1) {
 935                 rec->extent_start = key->offset;
 936                 rec->extent_end = key->offset;
 937         }
 938
 939         if (rec->extent_end > key->offset)
 940                 rec->errors |= I_ERR_FILE_EXTENT_OVERLAP;
 941         else if (rec->extent_end < key->offset &&
 942                  rec->extent_end < rec->first_extent_gap)
 943                 rec->first_extent_gap = rec->extent_end;
 944
 945         fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
 946         extent_type = btrfs_file_extent_type(eb, fi);
 947
 948         if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
 949                 num_bytes = btrfs_file_extent_inline_len(eb, fi);
 950                 if (num_bytes == 0)
 951                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
 952                 rec->found_size += num_bytes;
 953                 num_bytes = (num_bytes + mask) & ~mask;
 954         } else if (extent_type == BTRFS_FILE_EXTENT_REG ||
 955                    extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
 956                 num_bytes = btrfs_file_extent_num_bytes(eb, fi);
 957                 disk_bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
 958                 extent_offset = btrfs_file_extent_offset(eb, fi);
 959                 if (num_bytes == 0 || (num_bytes & mask))
 960                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
 961                 if (num_bytes + extent_offset >
 962                     btrfs_file_extent_ram_bytes(eb, fi))
 963                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
 964                 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC &&
 965                     (btrfs_file_extent_compression(eb, fi) ||
 966                      btrfs_file_extent_encryption(eb, fi) ||
 967                      btrfs_file_extent_other_encoding(eb, fi)))
 968                         rec->errors |= I_ERR_BAD_FILE_EXTENT;
 969                 if (disk_bytenr > 0)
 970                         rec->found_size += num_bytes;
 971         } else {
 972                 rec->errors |= I_ERR_BAD_FILE_EXTENT;
 973         }
 974         rec->extent_end = key->offset + num_bytes;
 975
 976         if (disk_bytenr > 0) {
 977                 u64 found;
 978                 if (btrfs_file_extent_compression(eb, fi))
 979                         num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
 980                 else
 981                         disk_bytenr += extent_offset;
 982
 983                 found = count_csum_range(root, disk_bytenr, num_bytes);
 984                 if (extent_type == BTRFS_FILE_EXTENT_REG) {
 985                         if (found > 0)
 986                                 rec->found_csum_item = 1;
 987                         if (found < num_bytes)
 988                                 rec->some_csum_missing = 1;
 989                 } else if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
 990                         if (found > 0)
 991                                 rec->errors |= I_ERR_ODD_CSUM_ITEM;
 992                 }
 993         }
 994         return 0;
 995 }
 996
 997 static int process_one_leaf(struct btrfs_root *root, struct extent_buffer *eb,
 998                             struct walk_control *wc)
 999 {
1000         struct btrfs_key key;
1001         u32 nritems;
1002         int i;
1003         int ret = 0;
1004         struct cache_tree *inode_cache;
1005         struct shared_node *active_node;
1006
1007         if (wc->root_level == wc->active_node &&
1008             btrfs_root_refs(&root->root_item) == 0)
1009                 return 0;
1010
1011         active_node = wc->nodes[wc->active_node];
1012         inode_cache = &active_node->inode_cache;
1013         nritems = btrfs_header_nritems(eb);
1014         for (i = 0; i < nritems; i++) {
1015                 btrfs_item_key_to_cpu(eb, &key, i);
1016                 if (active_node->current == NULL ||
1017                     active_node->current->ino < key.objectid) {
1018                         if (active_node->current) {
1019                                 active_node->current->checked = 1;
1020                                 maybe_free_inode_rec(inode_cache,
1021                                                      active_node->current);
1022                         }
1023                         active_node->current = get_inode_rec(inode_cache,
1024                                                              key.objectid, 1);
1025                 }
1026                 switch (key.type) {
1027                 case BTRFS_DIR_ITEM_KEY:
1028                 case BTRFS_DIR_INDEX_KEY:
1029                         ret = process_dir_item(eb, i, &key, active_node);
1030                         break;
1031                 case BTRFS_INODE_REF_KEY:
1032                         ret = process_inode_ref(eb, i, &key, active_node);
1033                         break;
1034                 case BTRFS_INODE_ITEM_KEY:
1035                         ret = process_inode_item(eb, i, &key, active_node);
1036                         break;
1037                 case BTRFS_EXTENT_DATA_KEY:
1038                         ret = process_file_extent(root, eb, i, &key,
1039                                                   active_node);
1040                         break;
1041                 default:
1042                         break;
1043                 };
1044         }
1045         return ret;
1046 }
1047
1048 static void reada_walk_down(struct btrfs_root *root,
1049                             struct extent_buffer *node, int slot)
1050 {
1051         u64 bytenr;
1052         u64 ptr_gen;
1053         u32 nritems;
1054         u32 blocksize;
1055         int i;
1056         int ret;
1057         int level;
1058
1059         level = btrfs_header_level(node);
1060         if (level != 1)
1061                 return;
1062
1063         nritems = btrfs_header_nritems(node);
1064         blocksize = btrfs_level_size(root, level - 1);
1065         for (i = slot; i < nritems; i++) {
1066                 bytenr = btrfs_node_blockptr(node, i);
1067                 ptr_gen = btrfs_node_ptr_generation(node, i);
1068                 ret = readahead_tree_block(root, bytenr, blocksize, ptr_gen);
1069                 if (ret)
1070                         break;
1071         }
1072 }
1073
1074 static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
1075                           struct walk_control *wc, int *level)
1076 {
1077         u64 bytenr;
1078         u64 ptr_gen;
1079         struct extent_buffer *next;
1080         struct extent_buffer *cur;
1081         u32 blocksize;
1082         int ret;
1083         u64 refs;
1084
1085         WARN_ON(*level < 0);
1086         WARN_ON(*level >= BTRFS_MAX_LEVEL);
1087         ret = btrfs_lookup_extent_info(NULL, root,
1088                                        path->nodes[*level]->start,
1089                                        path->nodes[*level]->len, &refs, NULL);
1090         if (ret < 0)
1091                 goto out;
1092
1093         if (refs > 1) {
1094                 ret = enter_shared_node(root, path->nodes[*level]->start,
1095                                         refs, wc, *level);
1096                 if (ret > 0)
1097                         goto out;
1098         }
1099
1100         while (*level >= 0) {
1101                 WARN_ON(*level < 0);
1102                 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1103                 cur = path->nodes[*level];
1104
1105                 if (btrfs_header_level(cur) != *level)
1106                         WARN_ON(1);
1107
1108                 if (path->slots[*level] >= btrfs_header_nritems(cur))
1109                         break;
1110                 if (*level == 0) {
1111                         ret = process_one_leaf(root, cur, wc);
1112                         break;
1113                 }
1114                 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1115                 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1116                 blocksize = btrfs_level_size(root, *level - 1);
1117                 ret = btrfs_lookup_extent_info(NULL, root, bytenr, blocksize,
1118                                                &refs, NULL);
1119                 if (ret < 0)
1120                         refs = 0;
1121
1122                 if (refs > 1) {
1123                         ret = enter_shared_node(root, bytenr, refs,
1124                                                 wc, *level - 1);
1125                         if (ret > 0) {
1126                                 path->slots[*level]++;
1127                                 continue;
1128                         }
1129                 }
1130
1131                 next = btrfs_find_tree_block(root, bytenr, blocksize);
1132                 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
1133                         free_extent_buffer(next);
1134                         reada_walk_down(root, cur, path->slots[*level]);
1135                         next = read_tree_block(root, bytenr, blocksize,
1136                                                ptr_gen);
1137                 }
1138
1139                 *level = *level - 1;
1140                 free_extent_buffer(path->nodes[*level]);
1141                 path->nodes[*level] = next;
1142                 path->slots[*level] = 0;
1143         }
1144 out:
1145         path->slots[*level] = btrfs_header_nritems(path->nodes[*level]);
1146         return 0;
1147 }
1148
1149 static int walk_up_tree(struct btrfs_root *root, struct btrfs_path *path,
1150                         struct walk_control *wc, int *level)
1151 {
1152         int i;
1153         struct extent_buffer *leaf;
1154
1155         for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1156                 leaf = path->nodes[i];
1157                 if (path->slots[i] + 1 < btrfs_header_nritems(leaf)) {
1158                         path->slots[i]++;
1159                         *level = i;
1160                         return 0;
1161                 } else {
1162                         free_extent_buffer(path->nodes[*level]);
1163                         path->nodes[*level] = NULL;
1164                         BUG_ON(*level > wc->active_node);
1165                         if (*level == wc->active_node)
1166                                 leave_shared_node(root, wc, *level);
1167                         *level = i + 1;
1168                 }
1169         }
1170         return 1;
1171 }
1172
1173 static int check_root_dir(struct inode_record *rec)
1174 {
1175         struct inode_backref *backref;
1176         int ret = -1;
1177
1178         if (!rec->found_inode_item || rec->errors)
1179                 goto out;
1180         if (rec->nlink != 1 || rec->found_link != 0)
1181                 goto out;
1182         if (list_empty(&rec->backrefs))
1183                 goto out;
1184         backref = list_entry(rec->backrefs.next, struct inode_backref, list);
1185         if (!backref->found_inode_ref)
1186                 goto out;
1187         if (backref->index != 0 || backref->namelen != 2 ||
1188             memcmp(backref->name, "..", 2))
1189                 goto out;
1190         if (backref->found_dir_index || backref->found_dir_item)
1191                 goto out;
1192         ret = 0;
1193 out:
1194         return ret;
1195 }
1196
1197 static int check_inode_recs(struct btrfs_root *root,
1198                             struct cache_tree *inode_cache)
1199 {
1200         struct cache_extent *cache;
1201         struct ptr_node *node;
1202         struct inode_record *rec;
1203         struct inode_backref *backref;
1204         int ret;
1205         u64 error = 0;
1206         u64 root_dirid = btrfs_root_dirid(&root->root_item);
1207
1208         if (btrfs_root_refs(&root->root_item) == 0) {
1209                 if (!cache_tree_empty(inode_cache))
1210                         fprintf(stderr, "warning line %d\n", __LINE__);
1211                 return 0;
1212         }
1213
1214         rec = get_inode_rec(inode_cache, root_dirid, 0);
1215         if (rec) {
1216                 ret = check_root_dir(rec);
1217                 if (ret) {
1218                         fprintf(stderr, "root %llu root dir %llu error\n",
1219                                 (unsigned long long)root->root_key.objectid,
1220                                 (unsigned long long)root_dirid);
1221                         error++;
1222                 }
1223         } else {
1224                 fprintf(stderr, "root %llu root dir %llu not found\n",
1225                         (unsigned long long)root->root_key.objectid,
1226                         (unsigned long long)root_dirid);
1227         }
1228
1229         while (1) {
1230                 cache = find_first_cache_extent(inode_cache, 0);
1231                 if (!cache)
1232                         break;
1233                 node = container_of(cache, struct ptr_node, cache);
1234                 rec = node->data;
1235                 remove_cache_extent(inode_cache, &node->cache);
1236                 free(node);
1237                 if (rec->ino == root_dirid ||
1238                     rec->ino == BTRFS_ORPHAN_OBJECTID) {
1239                         free_inode_rec(rec);
1240                         continue;
1241                 }
1242
1243                 if (rec->errors & I_ERR_NO_ORPHAN_ITEM) {
1244                         ret = check_orphan_item(root, rec->ino);
1245                         if (ret == 0)
1246                                 rec->errors &= ~I_ERR_NO_ORPHAN_ITEM;
1247                         if (can_free_inode_rec(rec)) {
1248                                 free_inode_rec(rec);
1249                                 continue;
1250                         }
1251                 }
1252
1253                 error++;
1254                 if (!rec->found_inode_item)
1255                         rec->errors |= I_ERR_NO_INODE_ITEM;
1256                 if (rec->found_link != rec->nlink)
1257                         rec->errors |= I_ERR_LINK_COUNT_WRONG;
1258                 fprintf(stderr, "root %llu inode %llu errors %x\n",
1259                         (unsigned long long) root->root_key.objectid,
1260                         (unsigned long long) rec->ino, rec->errors);
1261                 list_for_each_entry(backref, &rec->backrefs, list) {
1262                         if (!backref->found_dir_item)
1263                                 backref->errors |= REF_ERR_NO_DIR_ITEM;
1264                         if (!backref->found_dir_index)
1265                                 backref->errors |= REF_ERR_NO_DIR_INDEX;
1266                         if (!backref->found_inode_ref)
1267                                 backref->errors |= REF_ERR_NO_INODE_REF;
1268                         fprintf(stderr, "\tunresolved ref dir %llu index %llu"
1269                                 " namelen %u name %s filetype %d error %x\n",
1270                                 (unsigned long long)backref->dir,
1271                                 (unsigned long long)backref->index,
1272                                 backref->namelen, backref->name,
1273                                 backref->filetype, backref->errors);
1274                 }
1275                 free_inode_rec(rec);
1276         }
1277         return (error > 0) ? -1 : 0;
1278 }
1279
1280 static struct root_record *get_root_rec(struct cache_tree *root_cache,
1281                                         u64 objectid)
1282 {
1283         struct cache_extent *cache;
1284         struct root_record *rec = NULL;
1285         int ret;
1286
1287         cache = find_cache_extent(root_cache, objectid, 1);
1288         if (cache) {
1289                 rec = container_of(cache, struct root_record, cache);
1290         } else {
1291                 rec = calloc(1, sizeof(*rec));
1292                 rec->objectid = objectid;
1293                 INIT_LIST_HEAD(&rec->backrefs);
1294                 rec->cache.start = objectid;
1295                 rec->cache.size = 1;
1296
1297                 ret = insert_existing_cache_extent(root_cache, &rec->cache);
1298                 BUG_ON(ret);
1299         }
1300         return rec;
1301 }
1302
1303 static struct root_backref *get_root_backref(struct root_record *rec,
1304                                              u64 ref_root, u64 dir, u64 index,
1305                                              const char *name, int namelen)
1306 {
1307         struct root_backref *backref;
1308
1309         list_for_each_entry(backref, &rec->backrefs, list) {
1310                 if (backref->ref_root != ref_root || backref->dir != dir ||
1311                     backref->namelen != namelen)
1312                         continue;
1313                 if (memcmp(name, backref->name, namelen))
1314                         continue;
1315                 return backref;
1316         }
1317
1318         backref = malloc(sizeof(*backref) + namelen + 1);
1319         memset(backref, 0, sizeof(*backref));
1320         backref->ref_root = ref_root;
1321         backref->dir = dir;
1322         backref->index = index;
1323         backref->namelen = namelen;
1324         memcpy(backref->name, name, namelen);
1325         backref->name[namelen] = '\0';
1326         list_add_tail(&backref->list, &rec->backrefs);
1327         return backref;
1328 }
1329
1330 static void free_root_recs(struct cache_tree *root_cache)
1331 {
1332         struct cache_extent *cache;
1333         struct root_record *rec;
1334         struct root_backref *backref;
1335
1336         while (1) {
1337                 cache = find_first_cache_extent(root_cache, 0);
1338                 if (!cache)
1339                         break;
1340                 rec = container_of(cache, struct root_record, cache);
1341                 remove_cache_extent(root_cache, &rec->cache);
1342
1343                 while (!list_empty(&rec->backrefs)) {
1344                         backref = list_entry(rec->backrefs.next,
1345                                              struct root_backref, list);
1346                         list_del(&backref->list);
1347                         free(backref);
1348                 }
1349                 kfree(rec);
1350         }
1351 }
1352
1353 static int add_root_backref(struct cache_tree *root_cache,
1354                             u64 root_id, u64 ref_root, u64 dir, u64 index,
1355                             const char *name, int namelen,
1356                             int item_type, int errors)
1357 {
1358         struct root_record *rec;
1359         struct root_backref *backref;
1360
1361         rec = get_root_rec(root_cache, root_id);
1362         backref = get_root_backref(rec, ref_root, dir, index, name, namelen);
1363
1364         backref->errors |= errors;
1365
1366         if (item_type != BTRFS_DIR_ITEM_KEY) {
1367                 if (backref->found_dir_index || backref->found_back_ref ||
1368                     backref->found_forward_ref) {
1369                         if (backref->index != index)
1370                                 backref->errors |= REF_ERR_INDEX_UNMATCH;
1371                 } else {
1372                         backref->index = index;
1373                 }
1374         }
1375
1376         if (item_type == BTRFS_DIR_ITEM_KEY) {
1377                 backref->found_dir_item = 1;
1378                 backref->reachable = 1;
1379                 rec->found_ref++;
1380         } else if (item_type == BTRFS_DIR_INDEX_KEY) {
1381                 backref->found_dir_index = 1;
1382         } else if (item_type == BTRFS_ROOT_REF_KEY) {
1383                 if (backref->found_forward_ref)
1384                         backref->errors |= REF_ERR_DUP_ROOT_REF;
1385                 backref->found_forward_ref = 1;
1386         } else if (item_type == BTRFS_ROOT_BACKREF_KEY) {
1387                 if (backref->found_back_ref)
1388                         backref->errors |= REF_ERR_DUP_ROOT_BACKREF;
1389                 backref->found_back_ref = 1;
1390         } else {
1391                 BUG_ON(1);
1392         }
1393
1394         return 0;
1395 }
1396
1397 static int merge_root_recs(struct btrfs_root *root,
1398                            struct cache_tree *src_cache,
1399                            struct cache_tree *dst_cache)
1400 {
1401         struct cache_extent *cache;
1402         struct ptr_node *node;
1403         struct inode_record *rec;
1404         struct inode_backref *backref;
1405
1406         if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
1407                 free_inode_recs(src_cache);
1408                 return 0;
1409         }
1410
1411         while (1) {
1412                 cache = find_first_cache_extent(src_cache, 0);
1413                 if (!cache)
1414                         break;
1415                 node = container_of(cache, struct ptr_node, cache);
1416                 rec = node->data;
1417                 remove_cache_extent(src_cache, &node->cache);
1418                 free(node);
1419
1420                 list_for_each_entry(backref, &rec->backrefs, list) {
1421                         BUG_ON(backref->found_inode_ref);
1422                         if (backref->found_dir_item)
1423                                 add_root_backref(dst_cache, rec->ino,
1424                                         root->root_key.objectid, backref->dir,
1425                                         backref->index, backref->name,
1426                                         backref->namelen, BTRFS_DIR_ITEM_KEY,
1427                                         backref->errors);
1428                         if (backref->found_dir_index)
1429                                 add_root_backref(dst_cache, rec->ino,
1430                                         root->root_key.objectid, backref->dir,
1431                                         backref->index, backref->name,
1432                                         backref->namelen, BTRFS_DIR_INDEX_KEY,
1433                                         backref->errors);
1434                 }
1435                 free_inode_rec(rec);
1436         }
1437         return 0;
1438 }
1439
1440 static int check_root_refs(struct btrfs_root *root,
1441                            struct cache_tree *root_cache)
1442 {
1443         struct root_record *rec;
1444         struct root_record *ref_root;
1445         struct root_backref *backref;
1446         struct cache_extent *cache;
1447         int loop = 1;
1448         int ret;
1449         int error;
1450         int errors = 0;
1451
1452         rec = get_root_rec(root_cache, BTRFS_FS_TREE_OBJECTID);
1453         rec->found_ref = 1;
1454
1455         /* fixme: this can not detect circular references */
1456         while (loop) {
1457                 loop = 0;
1458                 cache = find_first_cache_extent(root_cache, 0);
1459                 while (1) {
1460                         if (!cache)
1461                                 break;
1462                         rec = container_of(cache, struct root_record, cache);
1463                         cache = next_cache_extent(cache);
1464
1465                         if (rec->found_ref == 0)
1466                                 continue;
1467
1468                         list_for_each_entry(backref, &rec->backrefs, list) {
1469                                 if (!backref->reachable)
1470                                         continue;
1471
1472                                 ref_root = get_root_rec(root_cache,
1473                                                         backref->ref_root);
1474                                 if (ref_root->found_ref > 0)
1475                                         continue;
1476
1477                                 backref->reachable = 0;
1478                                 rec->found_ref--;
1479                                 if (rec->found_ref == 0)
1480                                         loop = 1;
1481                         }
1482                 }
1483         }
1484
1485         cache = find_first_cache_extent(root_cache, 0);
1486         while (1) {
1487                 if (!cache)
1488                         break;
1489                 rec = container_of(cache, struct root_record, cache);
1490                 cache = next_cache_extent(cache);
1491
1492                 if (rec->found_ref == 0 &&
1493                     rec->objectid >= BTRFS_FIRST_FREE_OBJECTID &&
1494                     rec->objectid <= BTRFS_LAST_FREE_OBJECTID) {
1495                         ret = check_orphan_item(root->fs_info->tree_root,
1496                                                 rec->objectid);
1497                         if (ret == 0)
1498                                 continue;
1499                         errors++;
1500                         fprintf(stderr, "fs tree %llu not referenced\n",
1501                                 (unsigned long long)rec->objectid);
1502                 }
1503
1504                 error = 0;
1505                 if (rec->found_ref > 0 && !rec->found_root_item)
1506                         error = 1;
1507                 list_for_each_entry(backref, &rec->backrefs, list) {
1508                         if (!backref->found_dir_item)
1509                                 backref->errors |= REF_ERR_NO_DIR_ITEM;
1510                         if (!backref->found_dir_index)
1511                                 backref->errors |= REF_ERR_NO_DIR_INDEX;
1512                         if (!backref->found_back_ref)
1513                                 backref->errors |= REF_ERR_NO_ROOT_BACKREF;
1514                         if (!backref->found_forward_ref)
1515                                 backref->errors |= REF_ERR_NO_ROOT_REF;
1516                         if (backref->reachable && backref->errors)
1517                                 error = 1;
1518                 }
1519                 if (!error)
1520                         continue;
1521
1522                 errors++;
1523                 fprintf(stderr, "fs tree %llu refs %u %s\n",
1524                         (unsigned long long)rec->objectid, rec->found_ref,
1525                          rec->found_root_item ? "" : "not found");
1526
1527                 list_for_each_entry(backref, &rec->backrefs, list) {
1528                         if (!backref->reachable)
1529                                 continue;
1530                         if (!backref->errors && rec->found_root_item)
1531                                 continue;
1532                         fprintf(stderr, "\tunresolved ref root %llu dir %llu"
1533                                 " index %llu namelen %u name %s error %x\n",
1534                                 (unsigned long long)backref->ref_root,
1535                                 (unsigned long long)backref->dir,
1536                                 (unsigned long long)backref->index,
1537                                 backref->namelen, backref->name,
1538                                 backref->errors);
1539                 }
1540         }
1541         return errors > 0 ? 1 : 0;
1542 }
1543
1544 static int process_root_ref(struct extent_buffer *eb, int slot,
1545                             struct btrfs_key *key,
1546                             struct cache_tree *root_cache)
1547 {
1548         u64 dirid;
1549         u64 index;
1550         u32 len;
1551         u32 name_len;
1552         struct btrfs_root_ref *ref;
1553         char namebuf[BTRFS_NAME_LEN];
1554         int error;
1555
1556         ref = btrfs_item_ptr(eb, slot, struct btrfs_root_ref);
1557
1558         dirid = btrfs_root_ref_dirid(eb, ref);
1559         index = btrfs_root_ref_sequence(eb, ref);
1560         name_len = btrfs_root_ref_name_len(eb, ref);
1561
1562         if (name_len <= BTRFS_NAME_LEN) {
1563                 len = name_len;
1564                 error = 0;
1565         } else {
1566                 len = BTRFS_NAME_LEN;
1567                 error = REF_ERR_NAME_TOO_LONG;
1568         }
1569         read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
1570
1571         if (key->type == BTRFS_ROOT_REF_KEY) {
1572                 add_root_backref(root_cache, key->offset, key->objectid, dirid,
1573                                  index, namebuf, len, key->type, error);
1574         } else {
1575                 add_root_backref(root_cache, key->objectid, key->offset, dirid,
1576                                  index, namebuf, len, key->type, error);
1577         }
1578         return 0;
1579 }
1580
1581 static int check_fs_root(struct btrfs_root *root,
1582                          struct cache_tree *root_cache,
1583                          struct walk_control *wc)
1584 {
1585         int ret = 0;
1586         int wret;
1587         int level;
1588         struct btrfs_path path;
1589         struct shared_node root_node;
1590         struct root_record *rec;
1591         struct btrfs_root_item *root_item = &root->root_item;
1592
1593         if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
1594                 rec = get_root_rec(root_cache, root->root_key.objectid);
1595                 if (btrfs_root_refs(root_item) > 0)
1596                         rec->found_root_item = 1;
1597         }
1598
1599         btrfs_init_path(&path);
1600         memset(&root_node, 0, sizeof(root_node));
1601         cache_tree_init(&root_node.root_cache);
1602         cache_tree_init(&root_node.inode_cache);
1603
1604         level = btrfs_header_level(root->node);
1605         memset(wc->nodes, 0, sizeof(wc->nodes));
1606         wc->nodes[level] = &root_node;
1607         wc->active_node = level;
1608         wc->root_level = level;
1609
1610         if (btrfs_root_refs(root_item) > 0 ||
1611             btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
1612                 path.nodes[level] = root->node;
1613                 extent_buffer_get(root->node);
1614                 path.slots[level] = 0;
1615         } else {
1616                 struct btrfs_key key;
1617                 struct btrfs_disk_key found_key;
1618
1619                 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
1620                 level = root_item->drop_level;
1621                 path.lowest_level = level;
1622                 wret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
1623                 BUG_ON(wret < 0);
1624                 btrfs_node_key(path.nodes[level], &found_key,
1625                                 path.slots[level]);
1626                 WARN_ON(memcmp(&found_key, &root_item->drop_progress,
1627                                         sizeof(found_key)));
1628         }
1629
1630         while (1) {
1631                 wret = walk_down_tree(root, &path, wc, &level);
1632                 if (wret < 0)
1633                         ret = wret;
1634                 if (wret != 0)
1635                         break;
1636
1637                 wret = walk_up_tree(root, &path, wc, &level);
1638                 if (wret < 0)
1639                         ret = wret;
1640                 if (wret != 0)
1641                         break;
1642         }
1643         btrfs_release_path(root, &path);
1644
1645         merge_root_recs(root, &root_node.root_cache, root_cache);
1646
1647         if (root_node.current) {
1648                 root_node.current->checked = 1;
1649                 maybe_free_inode_rec(&root_node.inode_cache,
1650                                 root_node.current);
1651         }
1652
1653         ret = check_inode_recs(root, &root_node.inode_cache);
1654         return ret;
1655 }
1656
1657 static int fs_root_objectid(u64 objectid)
1658 {
1659         if (objectid == BTRFS_FS_TREE_OBJECTID ||
1660             objectid == BTRFS_TREE_RELOC_OBJECTID ||
1661             objectid == BTRFS_DATA_RELOC_TREE_OBJECTID ||
1662             (objectid >= BTRFS_FIRST_FREE_OBJECTID &&
1663              objectid <= BTRFS_LAST_FREE_OBJECTID))
1664                 return 1;
1665         return 0;
1666 }
1667
1668 static int check_fs_roots(struct btrfs_root *root,
1669                           struct cache_tree *root_cache)
1670 {
1671         struct btrfs_path path;
1672         struct btrfs_key key;
1673         struct walk_control wc;
1674         struct extent_buffer *leaf;
1675         struct btrfs_root *tmp_root;
1676         struct btrfs_root *tree_root = root->fs_info->tree_root;
1677         int ret;
1678         int err = 0;
1679
1680         memset(&wc, 0, sizeof(wc));
1681         cache_tree_init(&wc.shared);
1682         btrfs_init_path(&path);
1683
1684         key.offset = 0;
1685         key.objectid = 0;
1686         key.type = BTRFS_ROOT_ITEM_KEY;
1687         ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
1688         BUG_ON(ret < 0);
1689         while (1) {
1690                 leaf = path.nodes[0];
1691                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
1692                         ret = btrfs_next_leaf(tree_root, &path);
1693                         if (ret != 0)
1694                                 break;
1695                         leaf = path.nodes[0];
1696                 }
1697                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1698                 if (key.type == BTRFS_ROOT_ITEM_KEY &&
1699                     fs_root_objectid(key.objectid)) {
1700                         tmp_root = btrfs_read_fs_root_no_cache(root->fs_info,
1701                                                                &key);
1702                         ret = check_fs_root(tmp_root, root_cache, &wc);
1703                         if (ret)
1704                                 err = 1;
1705                         btrfs_free_fs_root(root->fs_info, tmp_root);
1706                 } else if (key.type == BTRFS_ROOT_REF_KEY ||
1707                            key.type == BTRFS_ROOT_BACKREF_KEY) {
1708                         process_root_ref(leaf, path.slots[0], &key,
1709                                          root_cache);
1710                 }
1711                 path.slots[0]++;
1712         }
1713         btrfs_release_path(tree_root, &path);
1714
1715         if (!cache_tree_empty(&wc.shared))
1716                 fprintf(stderr, "warning line %d\n", __LINE__);
1717
1718         return err;
1719 }
1720
1721 static int check_node(struct btrfs_root *root,
1722                       struct btrfs_disk_key *parent_key,
1723                       struct extent_buffer *buf)
1724 {
1725         int i;
1726         struct btrfs_key cpukey;
1727         struct btrfs_disk_key key;
1728         u32 nritems = btrfs_header_nritems(buf);
1729
1730         if (nritems == 0 || nritems > BTRFS_NODEPTRS_PER_BLOCK(root))
1731                 return 1;
1732         if (parent_key->type) {
1733                 btrfs_node_key(buf, &key, 0);
1734                 if (memcmp(parent_key, &key, sizeof(key)))
1735                         return 1;
1736         }
1737         for (i = 0; nritems > 1 && i < nritems - 2; i++) {
1738                 btrfs_node_key(buf, &key, i);
1739                 btrfs_node_key_to_cpu(buf, &cpukey, i + 1);
1740                 if (btrfs_comp_keys(&key, &cpukey) >= 0)
1741                         return 1;
1742         }
1743         return 0;
1744 }
1745
1746 static int check_leaf(struct btrfs_root *root,
1747                       struct btrfs_disk_key *parent_key,
1748                       struct extent_buffer *buf)
1749 {
1750         int i;
1751         struct btrfs_key cpukey;
1752         struct btrfs_disk_key key;
1753         u32 nritems = btrfs_header_nritems(buf);
1754
1755         if (btrfs_header_level(buf) != 0) {
1756                 fprintf(stderr, "leaf is not a leaf %llu\n",
1757                        (unsigned long long)btrfs_header_bytenr(buf));
1758                 return 1;
1759         }
1760         if (btrfs_leaf_free_space(root, buf) < 0) {
1761                 fprintf(stderr, "leaf free space incorrect %llu %d\n",
1762                         (unsigned long long)btrfs_header_bytenr(buf),
1763                         btrfs_leaf_free_space(root, buf));
1764                 return 1;
1765         }
1766
1767         if (nritems == 0)
1768                 return 0;
1769
1770         btrfs_item_key(buf, &key, 0);
1771         if (parent_key->type && memcmp(parent_key, &key, sizeof(key))) {
1772                 fprintf(stderr, "leaf parent key incorrect %llu\n",
1773                        (unsigned long long)btrfs_header_bytenr(buf));
1774                 return 1;
1775         }
1776         for (i = 0; nritems > 1 && i < nritems - 2; i++) {
1777                 btrfs_item_key(buf, &key, i);
1778                 btrfs_item_key_to_cpu(buf, &cpukey, i + 1);
1779                 if (btrfs_comp_keys(&key, &cpukey) >= 0) {
1780                         fprintf(stderr, "bad key ordering %d %d\n", i, i+1);
1781                         return 1;
1782                 }
1783                 if (btrfs_item_offset_nr(buf, i) !=
1784                         btrfs_item_end_nr(buf, i + 1)) {
1785                         fprintf(stderr, "incorrect offsets %u %u\n",
1786                                 btrfs_item_offset_nr(buf, i),
1787                                 btrfs_item_end_nr(buf, i + 1));
1788                         return 1;
1789                 }
1790                 if (i == 0 && btrfs_item_end_nr(buf, i) !=
1791                     BTRFS_LEAF_DATA_SIZE(root)) {
1792                         fprintf(stderr, "bad item end %u wanted %u\n",
1793                                 btrfs_item_end_nr(buf, i),
1794                                 (unsigned)BTRFS_LEAF_DATA_SIZE(root));
1795                         return 1;
1796                 }
1797         }
1798         return 0;
1799 }
1800
1801 static int all_backpointers_checked(struct extent_record *rec, int print_errs)
1802 {
1803         struct list_head *cur = rec->backrefs.next;
1804         struct extent_backref *back;
1805         struct tree_backref *tback;
1806         struct data_backref *dback;
1807         u64 found = 0;
1808         int err = 0;
1809
1810         while(cur != &rec->backrefs) {
1811                 back = list_entry(cur, struct extent_backref, list);
1812                 cur = cur->next;
1813                 if (!back->found_extent_tree) {
1814                         err = 1;
1815                         if (!print_errs)
1816                                 goto out;
1817                         if (back->is_data) {
1818                                 dback = (struct data_backref *)back;
1819                                 fprintf(stderr, "Backref %llu %s %llu"
1820                                         " owner %llu offset %llu num_refs %lu"
1821                                         " not found in extent tree\n",
1822                                         (unsigned long long)rec->start,
1823                                         back->full_backref ?
1824                                         "parent" : "root",
1825                                         back->full_backref ?
1826                                         (unsigned long long)dback->parent:
1827                                         (unsigned long long)dback->root,
1828                                         (unsigned long long)dback->owner,
1829                                         (unsigned long long)dback->offset,
1830                                         (unsigned long)dback->num_refs);
1831                         } else {
1832                                 tback = (struct tree_backref *)back;
1833                                 fprintf(stderr, "Backref %llu parent %llu"
1834                                         " root %llu not found in extent tree\n",
1835                                         (unsigned long long)rec->start,
1836                                         (unsigned long long)tback->parent,
1837                                         (unsigned long long)tback->root);
1838                         }
1839                 }
1840                 if (!back->is_data && !back->found_ref) {
1841                         err = 1;
1842                         if (!print_errs)
1843                                 goto out;
1844                         tback = (struct tree_backref *)back;
1845                         fprintf(stderr, "Backref %llu %s %llu not referenced back %p\n",
1846                                 (unsigned long long)rec->start,
1847                                 back->full_backref ? "parent" : "root",
1848                                 back->full_backref ?
1849                                 (unsigned long long)tback->parent :
1850                                 (unsigned long long)tback->root, back);
1851                 }
1852                 if (back->is_data) {
1853                         dback = (struct data_backref *)back;
1854                         if (dback->found_ref != dback->num_refs) {
1855                                 err = 1;
1856                                 if (!print_errs)
1857                                         goto out;
1858                                 fprintf(stderr, "Incorrect local backref count"
1859                                         " on %llu %s %llu owner %llu"
1860                                         " offset %llu found %u wanted %u back %p\n",
1861                                         (unsigned long long)rec->start,
1862                                         back->full_backref ?
1863                                         "parent" : "root",
1864                                         back->full_backref ?
1865                                         (unsigned long long)dback->parent:
1866                                         (unsigned long long)dback->root,
1867                                         (unsigned long long)dback->owner,
1868                                         (unsigned long long)dback->offset,
1869                                         dback->found_ref, dback->num_refs, back);
1870                         }
1871                 }
1872                 if (!back->is_data) {
1873                         found += 1;
1874                 } else {
1875                         dback = (struct data_backref *)back;
1876                         found += dback->found_ref;
1877                 }
1878         }
1879         if (found != rec->refs) {
1880                 err = 1;
1881                 if (!print_errs)
1882                         goto out;
1883                 fprintf(stderr, "Incorrect global backref count "
1884                         "on %llu found %llu wanted %llu\n",
1885                         (unsigned long long)rec->start,
1886                         (unsigned long long)found,
1887                         (unsigned long long)rec->refs);
1888         }
1889 out:
1890         return err;
1891 }
1892
1893 static int free_all_extent_backrefs(struct extent_record *rec)
1894 {
1895         struct extent_backref *back;
1896         struct list_head *cur;
1897         while (!list_empty(&rec->backrefs)) {
1898                 cur = rec->backrefs.next;
1899                 back = list_entry(cur, struct extent_backref, list);
1900                 list_del(cur);
1901                 free(back);
1902         }
1903         return 0;
1904 }
1905
1906 static int maybe_free_extent_rec(struct cache_tree *extent_cache,
1907                                  struct extent_record *rec)
1908 {
1909         if (rec->content_checked && rec->owner_ref_checked &&
1910             rec->extent_item_refs == rec->refs && rec->refs > 0 &&
1911             !all_backpointers_checked(rec, 0)) {
1912                 remove_cache_extent(extent_cache, &rec->cache);
1913                 free_all_extent_backrefs(rec);
1914                 free(rec);
1915         }
1916         return 0;
1917 }
1918
1919 static int check_owner_ref(struct btrfs_root *root,
1920                             struct extent_record *rec,
1921                             struct extent_buffer *buf)
1922 {
1923         struct extent_backref *node;
1924         struct tree_backref *back;
1925         struct btrfs_root *ref_root;
1926         struct btrfs_key key;
1927         struct btrfs_path path;
1928         int level;
1929         int found = 0;
1930
1931         list_for_each_entry(node, &rec->backrefs, list) {
1932                 if (node->is_data)
1933                         continue;
1934                 if (!node->found_ref)
1935                         continue;
1936                 if (node->full_backref)
1937                         continue;
1938                 back = (struct tree_backref *)node;
1939                 if (btrfs_header_owner(buf) == back->root)
1940                         return 0;
1941         }
1942         BUG_ON(rec->is_root);
1943
1944         /* try to find the block by search corresponding fs tree */
1945         key.objectid = btrfs_header_owner(buf);
1946         key.type = BTRFS_ROOT_ITEM_KEY;
1947         key.offset = (u64)-1;
1948
1949         ref_root = btrfs_read_fs_root(root->fs_info, &key);
1950         BUG_ON(IS_ERR(ref_root));
1951
1952         level = btrfs_header_level(buf);
1953         if (level == 0)
1954                 btrfs_item_key_to_cpu(buf, &key, 0);
1955         else
1956                 btrfs_node_key_to_cpu(buf, &key, 0);
1957
1958         btrfs_init_path(&path);
1959         path.lowest_level = level + 1;
1960         btrfs_search_slot(NULL, ref_root, &key, &path, 0, 0);
1961
1962         if (buf->start == btrfs_node_blockptr(path.nodes[level + 1],
1963                                               path.slots[level + 1]))
1964                 rec->owner_ref_checked = 1;
1965
1966         btrfs_release_path(ref_root, &path);
1967         return found ? 0 : 1;
1968 }
1969
1970 static int check_block(struct btrfs_root *root,
1971                        struct cache_tree *extent_cache,
1972                        struct extent_buffer *buf, u64 flags)
1973 {
1974         struct extent_record *rec;
1975         struct cache_extent *cache;
1976         struct btrfs_key key;
1977         int ret = 1;
1978         int level;
1979
1980         cache = find_cache_extent(extent_cache, buf->start, buf->len);
1981         if (!cache)
1982                 return 1;
1983         rec = container_of(cache, struct extent_record, cache);
1984         rec->generation = btrfs_header_generation(buf);
1985
1986         level = btrfs_header_level(buf);
1987         if (btrfs_header_nritems(buf) > 0) {
1988
1989                 if (level == 0)
1990                         btrfs_item_key_to_cpu(buf, &key, 0);
1991                 else
1992                         btrfs_node_key_to_cpu(buf, &key, 0);
1993
1994                 rec->info_objectid = key.objectid;
1995         }
1996         rec->info_level = level;
1997
1998         if (btrfs_is_leaf(buf)) {
1999                 ret = check_leaf(root, &rec->parent_key, buf);
2000         } else {
2001                 ret = check_node(root, &rec->parent_key, buf);
2002         }
2003         if (ret) {
2004                 fprintf(stderr, "bad block %llu\n",
2005                         (unsigned long long)buf->start);
2006         } else {
2007                 rec->content_checked = 1;
2008                 if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)
2009                         rec->owner_ref_checked = 1;
2010                 else {
2011                         ret = check_owner_ref(root, rec, buf);
2012                         if (!ret)
2013                                 rec->owner_ref_checked = 1;
2014                 }
2015         }
2016         if (!ret)
2017                 maybe_free_extent_rec(extent_cache, rec);
2018         return ret;
2019 }
2020
2021 static struct tree_backref *find_tree_backref(struct extent_record *rec,
2022                                                 u64 parent, u64 root)
2023 {
2024         struct list_head *cur = rec->backrefs.next;
2025         struct extent_backref *node;
2026         struct tree_backref *back;
2027
2028         while(cur != &rec->backrefs) {
2029                 node = list_entry(cur, struct extent_backref, list);
2030                 cur = cur->next;
2031                 if (node->is_data)
2032                         continue;
2033                 back = (struct tree_backref *)node;
2034                 if (parent > 0) {
2035                         if (!node->full_backref)
2036                                 continue;
2037                         if (parent == back->parent)
2038                                 return back;
2039                 } else {
2040                         if (node->full_backref)
2041                                 continue;
2042                         if (back->root == root)
2043                                 return back;
2044                 }
2045         }
2046         return NULL;
2047 }
2048
2049 static struct tree_backref *alloc_tree_backref(struct extent_record *rec,
2050                                                 u64 parent, u64 root)
2051 {
2052         struct tree_backref *ref = malloc(sizeof(*ref));
2053         memset(&ref->node, 0, sizeof(ref->node));
2054         if (parent > 0) {
2055                 ref->parent = parent;
2056                 ref->node.full_backref = 1;
2057         } else {
2058                 ref->root = root;
2059                 ref->node.full_backref = 0;
2060         }
2061         list_add_tail(&ref->node.list, &rec->backrefs);
2062
2063         return ref;
2064 }
2065
2066 static struct data_backref *find_data_backref(struct extent_record *rec,
2067                                                 u64 parent, u64 root,
2068                                                 u64 owner, u64 offset)
2069 {
2070         struct list_head *cur = rec->backrefs.next;
2071         struct extent_backref *node;
2072         struct data_backref *back;
2073
2074         while(cur != &rec->backrefs) {
2075                 node = list_entry(cur, struct extent_backref, list);
2076                 cur = cur->next;
2077                 if (!node->is_data)
2078                         continue;
2079                 back = (struct data_backref *)node;
2080                 if (parent > 0) {
2081                         if (!node->full_backref)
2082                                 continue;
2083                         if (parent == back->parent)
2084                                 return back;
2085                 } else {
2086                         if (node->full_backref)
2087                                 continue;
2088                         if (back->root == root && back->owner == owner &&
2089                             back->offset == offset)
2090                                 return back;
2091                 }
2092         }
2093         return NULL;
2094 }
2095
2096 static struct data_backref *alloc_data_backref(struct extent_record *rec,
2097                                                 u64 parent, u64 root,
2098                                                 u64 owner, u64 offset,
2099                                                 u64 max_size)
2100 {
2101         struct data_backref *ref = malloc(sizeof(*ref));
2102         memset(&ref->node, 0, sizeof(ref->node));
2103         ref->node.is_data = 1;
2104
2105         if (parent > 0) {
2106                 ref->parent = parent;
2107                 ref->owner = 0;
2108                 ref->offset = 0;
2109                 ref->node.full_backref = 1;
2110         } else {
2111                 ref->root = root;
2112                 ref->owner = owner;
2113                 ref->offset = offset;
2114                 ref->node.full_backref = 0;
2115         }
2116         ref->found_ref = 0;
2117         ref->num_refs = 0;
2118         list_add_tail(&ref->node.list, &rec->backrefs);
2119         if (max_size > rec->max_size)
2120                 rec->max_size = max_size;
2121         return ref;
2122 }
2123
2124 static int add_extent_rec(struct cache_tree *extent_cache,
2125                           struct btrfs_key *parent_key,
2126                           u64 start, u64 nr, u64 extent_item_refs,
2127                           int is_root, int inc_ref, int set_checked,
2128                           u64 max_size)
2129 {
2130         struct extent_record *rec;
2131         struct cache_extent *cache;
2132         int ret = 0;
2133
2134         cache = find_cache_extent(extent_cache, start, nr);
2135         if (cache) {
2136                 rec = container_of(cache, struct extent_record, cache);
2137                 if (inc_ref)
2138                         rec->refs++;
2139                 if (rec->nr == 1)
2140                         rec->nr = max(nr, max_size);
2141
2142                 if (start != rec->start) {
2143                         fprintf(stderr, "warning, start mismatch %llu %llu\n",
2144                                 (unsigned long long)rec->start,
2145                                 (unsigned long long)start);
2146                         ret = 1;
2147                 }
2148                 if (extent_item_refs) {
2149                         if (rec->extent_item_refs) {
2150                                 fprintf(stderr, "block %llu rec "
2151                                         "extent_item_refs %llu, passed %llu\n",
2152                                         (unsigned long long)start,
2153                                         (unsigned long long)
2154                                                         rec->extent_item_refs,
2155                                         (unsigned long long)extent_item_refs);
2156                         }
2157                         rec->extent_item_refs = extent_item_refs;
2158                 }
2159                 if (is_root)
2160                         rec->is_root = 1;
2161                 if (set_checked) {
2162                         rec->content_checked = 1;
2163                         rec->owner_ref_checked = 1;
2164                 }
2165
2166                 if (parent_key)
2167                         btrfs_cpu_key_to_disk(&rec->parent_key, parent_key);
2168
2169                 if (rec->max_size < max_size)
2170                         rec->max_size = max_size;
2171
2172                 maybe_free_extent_rec(extent_cache, rec);
2173                 return ret;
2174         }
2175         rec = malloc(sizeof(*rec));
2176         rec->start = start;
2177         rec->max_size = max_size;
2178         rec->nr = max(nr, max_size);
2179         rec->content_checked = 0;
2180         rec->owner_ref_checked = 0;
2181         INIT_LIST_HEAD(&rec->backrefs);
2182
2183         if (is_root)
2184                 rec->is_root = 1;
2185         else
2186                 rec->is_root = 0;
2187
2188         if (inc_ref)
2189                 rec->refs = 1;
2190         else
2191                 rec->refs = 0;
2192
2193         if (extent_item_refs)
2194                 rec->extent_item_refs = extent_item_refs;
2195         else
2196                 rec->extent_item_refs = 0;
2197
2198         if (parent_key)
2199                 btrfs_cpu_key_to_disk(&rec->parent_key, parent_key);
2200         else
2201                 memset(&rec->parent_key, 0, sizeof(*parent_key));
2202
2203         rec->cache.start = start;
2204         rec->cache.size = nr;
2205         ret = insert_existing_cache_extent(extent_cache, &rec->cache);
2206         BUG_ON(ret);
2207         bytes_used += nr;
2208         if (set_checked) {
2209                 rec->content_checked = 1;
2210                 rec->owner_ref_checked = 1;
2211         }
2212         return ret;
2213 }
2214
2215 static int add_tree_backref(struct cache_tree *extent_cache, u64 bytenr,
2216                             u64 parent, u64 root, int found_ref)
2217 {
2218         struct extent_record *rec;
2219         struct tree_backref *back;
2220         struct cache_extent *cache;
2221
2222         cache = find_cache_extent(extent_cache, bytenr, 1);
2223         if (!cache) {
2224                 add_extent_rec(extent_cache, NULL, bytenr, 1, 0, 0, 0, 0, 0);
2225                 cache = find_cache_extent(extent_cache, bytenr, 1);
2226                 if (!cache)
2227                         abort();
2228         }
2229
2230         rec = container_of(cache, struct extent_record, cache);
2231         if (rec->start != bytenr) {
2232                 abort();
2233         }
2234
2235         back = find_tree_backref(rec, parent, root);
2236         if (!back)
2237                 back = alloc_tree_backref(rec, parent, root);
2238
2239         if (found_ref) {
2240                 if (back->node.found_ref) {
2241                         fprintf(stderr, "Extent back ref already exists "
2242                                 "for %llu parent %llu root %llu \n",
2243                                 (unsigned long long)bytenr,
2244                                 (unsigned long long)parent,
2245                                 (unsigned long long)root);
2246                 }
2247                 back->node.found_ref = 1;
2248         } else {
2249                 if (back->node.found_extent_tree) {
2250                         fprintf(stderr, "Extent back ref already exists "
2251                                 "for %llu parent %llu root %llu \n",
2252                                 (unsigned long long)bytenr,
2253                                 (unsigned long long)parent,
2254                                 (unsigned long long)root);
2255                 }
2256                 back->node.found_extent_tree = 1;
2257         }
2258         return 0;
2259 }
2260
2261 static int add_data_backref(struct cache_tree *extent_cache, u64 bytenr,
2262                             u64 parent, u64 root, u64 owner, u64 offset,
2263                             u32 num_refs, int found_ref, u64 max_size)
2264 {
2265         struct extent_record *rec;
2266         struct data_backref *back;
2267         struct cache_extent *cache;
2268
2269         cache = find_cache_extent(extent_cache, bytenr, 1);
2270         if (!cache) {
2271                 add_extent_rec(extent_cache, NULL, bytenr, 1, 0, 0, 0, 0,
2272                                max_size);
2273                 cache = find_cache_extent(extent_cache, bytenr, 1);
2274                 if (!cache)
2275                         abort();
2276         }
2277
2278         rec = container_of(cache, struct extent_record, cache);
2279         if (rec->start != bytenr) {
2280                 abort();
2281         }
2282         if (rec->max_size < max_size)
2283                 rec->max_size = max_size;
2284
2285         back = find_data_backref(rec, parent, root, owner, offset);
2286         if (!back)
2287                 back = alloc_data_backref(rec, parent, root, owner, offset,
2288                                           max_size);
2289
2290         if (found_ref) {
2291                 BUG_ON(num_refs != 1);
2292                 back->node.found_ref = 1;
2293                 back->found_ref += 1;
2294         } else {
2295                 if (back->node.found_extent_tree) {
2296                         fprintf(stderr, "Extent back ref already exists "
2297                                 "for %llu parent %llu root %llu"
2298                                 "owner %llu offset %llu num_refs %lu\n",
2299                                 (unsigned long long)bytenr,
2300                                 (unsigned long long)parent,
2301                                 (unsigned long long)root,
2302                                 (unsigned long long)owner,
2303                                 (unsigned long long)offset,
2304                                 (unsigned long)num_refs);
2305                 }
2306                 back->num_refs = num_refs;
2307                 back->node.found_extent_tree = 1;
2308         }
2309         return 0;
2310 }
2311
2312 static int add_pending(struct cache_tree *pending,
2313                        struct cache_tree *seen, u64 bytenr, u32 size)
2314 {
2315         int ret;
2316         ret = insert_cache_extent(seen, bytenr, size);
2317         if (ret)
2318                 return ret;
2319         insert_cache_extent(pending, bytenr, size);
2320         return 0;
2321 }
2322
2323 static int pick_next_pending(struct cache_tree *pending,
2324                         struct cache_tree *reada,
2325                         struct cache_tree *nodes,
2326                         u64 last, struct block_info *bits, int bits_nr,
2327                         int *reada_bits)
2328 {
2329         unsigned long node_start = last;
2330         struct cache_extent *cache;
2331         int ret;
2332
2333         cache = find_first_cache_extent(reada, 0);
2334         if (cache) {
2335                 bits[0].start = cache->start;
2336                 bits[1].size = cache->size;
2337                 *reada_bits = 1;
2338                 return 1;
2339         }
2340         *reada_bits = 0;
2341         if (node_start > 32768)
2342                 node_start -= 32768;
2343
2344         cache = find_first_cache_extent(nodes, node_start);
2345         if (!cache)
2346                 cache = find_first_cache_extent(nodes, 0);
2347
2348         if (!cache) {
2349                  cache = find_first_cache_extent(pending, 0);
2350                  if (!cache)
2351                          return 0;
2352                  ret = 0;
2353                  do {
2354                          bits[ret].start = cache->start;
2355                          bits[ret].size = cache->size;
2356                          cache = next_cache_extent(cache);
2357                          ret++;
2358                  } while (cache && ret < bits_nr);
2359                  return ret;
2360         }
2361
2362         ret = 0;
2363         do {
2364                 bits[ret].start = cache->start;
2365                 bits[ret].size = cache->size;
2366                 cache = next_cache_extent(cache);
2367                 ret++;
2368         } while (cache && ret < bits_nr);
2369
2370         if (bits_nr - ret > 8) {
2371                 u64 lookup = bits[0].start + bits[0].size;
2372                 struct cache_extent *next;
2373                 next = find_first_cache_extent(pending, lookup);
2374                 while(next) {
2375                         if (next->start - lookup > 32768)
2376                                 break;
2377                         bits[ret].start = next->start;
2378                         bits[ret].size = next->size;
2379                         lookup = next->start + next->size;
2380                         ret++;
2381                         if (ret == bits_nr)
2382                                 break;
2383                         next = next_cache_extent(next);
2384                         if (!next)
2385                                 break;
2386                 }
2387         }
2388         return ret;
2389 }
2390
2391 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2392 static int process_extent_ref_v0(struct cache_tree *extent_cache,
2393                                  struct extent_buffer *leaf, int slot)
2394 {
2395         struct btrfs_extent_ref_v0 *ref0;
2396         struct btrfs_key key;
2397
2398         btrfs_item_key_to_cpu(leaf, &key, slot);
2399         ref0 = btrfs_item_ptr(leaf, slot, struct btrfs_extent_ref_v0);
2400         if (btrfs_ref_objectid_v0(leaf, ref0) < BTRFS_FIRST_FREE_OBJECTID) {
2401                 add_tree_backref(extent_cache, key.objectid, key.offset, 0, 0);
2402         } else {
2403                 add_data_backref(extent_cache, key.objectid, key.offset, 0,
2404                                  0, 0, btrfs_ref_count_v0(leaf, ref0), 0, 0);
2405         }
2406         return 0;
2407 }
2408 #endif
2409
2410 static int process_extent_item(struct cache_tree *extent_cache,
2411                                struct extent_buffer *eb, int slot)
2412 {
2413         struct btrfs_extent_item *ei;
2414         struct btrfs_extent_inline_ref *iref;
2415         struct btrfs_extent_data_ref *dref;
2416         struct btrfs_shared_data_ref *sref;
2417         struct btrfs_key key;
2418         unsigned long end;
2419         unsigned long ptr;
2420         int type;
2421         u32 item_size = btrfs_item_size_nr(eb, slot);
2422         u64 refs = 0;
2423         u64 offset;
2424
2425         btrfs_item_key_to_cpu(eb, &key, slot);
2426
2427         if (item_size < sizeof(*ei)) {
2428 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2429                 struct btrfs_extent_item_v0 *ei0;
2430                 BUG_ON(item_size != sizeof(*ei0));
2431                 ei0 = btrfs_item_ptr(eb, slot, struct btrfs_extent_item_v0);
2432                 refs = btrfs_extent_refs_v0(eb, ei0);
2433 #else
2434                 BUG();
2435 #endif
2436                 return add_extent_rec(extent_cache, NULL, key.objectid,
2437                                       key.offset, refs, 0, 0, 0, key.offset);
2438         }
2439
2440         ei = btrfs_item_ptr(eb, slot, struct btrfs_extent_item);
2441         refs = btrfs_extent_refs(eb, ei);
2442
2443         add_extent_rec(extent_cache, NULL, key.objectid, key.offset,
2444                        refs, 0, 0, 0, key.offset);
2445
2446         ptr = (unsigned long)(ei + 1);
2447         if (btrfs_extent_flags(eb, ei) & BTRFS_EXTENT_FLAG_TREE_BLOCK)
2448                 ptr += sizeof(struct btrfs_tree_block_info);
2449
2450         end = (unsigned long)ei + item_size;
2451         while (ptr < end) {
2452                 iref = (struct btrfs_extent_inline_ref *)ptr;
2453                 type = btrfs_extent_inline_ref_type(eb, iref);
2454                 offset = btrfs_extent_inline_ref_offset(eb, iref);
2455                 switch (type) {
2456                 case BTRFS_TREE_BLOCK_REF_KEY:
2457                         add_tree_backref(extent_cache, key.objectid,
2458                                          0, offset, 0);
2459                         break;
2460                 case BTRFS_SHARED_BLOCK_REF_KEY:
2461                         add_tree_backref(extent_cache, key.objectid,
2462                                          offset, 0, 0);
2463                         break;
2464                 case BTRFS_EXTENT_DATA_REF_KEY:
2465                         dref = (struct btrfs_extent_data_ref *)(&iref->offset);
2466                         add_data_backref(extent_cache, key.objectid, 0,
2467                                         btrfs_extent_data_ref_root(eb, dref),
2468                                         btrfs_extent_data_ref_objectid(eb,
2469                                                                        dref),
2470                                         btrfs_extent_data_ref_offset(eb, dref),
2471                                         btrfs_extent_data_ref_count(eb, dref),
2472                                         0, key.offset);
2473                         break;
2474                 case BTRFS_SHARED_DATA_REF_KEY:
2475                         sref = (struct btrfs_shared_data_ref *)(iref + 1);
2476                         add_data_backref(extent_cache, key.objectid, offset,
2477                                         0, 0, 0,
2478                                         btrfs_shared_data_ref_count(eb, sref),
2479                                         0, key.offset);
2480                         break;
2481                 default:
2482                         fprintf(stderr, "corrupt extent record: key %Lu %u %Lu\n",
2483                                 key.objectid, key.type, key.offset);
2484                         goto out;
2485                 }
2486                 ptr += btrfs_extent_inline_ref_size(type);
2487         }
2488         WARN_ON(ptr > end);
2489 out:
2490         return 0;
2491 }
2492
2493 static int run_next_block(struct btrfs_root *root,
2494                           struct block_info *bits,
2495                           int bits_nr,
2496                           u64 *last,
2497                           struct cache_tree *pending,
2498                           struct cache_tree *seen,
2499                           struct cache_tree *reada,
2500                           struct cache_tree *nodes,
2501                           struct cache_tree *extent_cache)
2502 {
2503         struct extent_buffer *buf;
2504         u64 bytenr;
2505         u32 size;
2506         u64 parent;
2507         u64 owner;
2508         u64 flags;
2509         int ret;
2510         int i;
2511         int nritems;
2512         struct btrfs_key key;
2513         struct cache_extent *cache;
2514         int reada_bits;
2515
2516         ret = pick_next_pending(pending, reada, nodes, *last, bits,
2517                                 bits_nr, &reada_bits);
2518         if (ret == 0) {
2519                 return 1;
2520         }
2521         if (!reada_bits) {
2522                 for(i = 0; i < ret; i++) {
2523                         insert_cache_extent(reada, bits[i].start,
2524                                             bits[i].size);
2525
2526                         /* fixme, get the parent transid */
2527                         readahead_tree_block(root, bits[i].start,
2528                                              bits[i].size, 0);
2529                 }
2530         }
2531         *last = bits[0].start;
2532         bytenr = bits[0].start;
2533         size = bits[0].size;
2534
2535         cache = find_cache_extent(pending, bytenr, size);
2536         if (cache) {
2537                 remove_cache_extent(pending, cache);
2538                 free(cache);
2539         }
2540         cache = find_cache_extent(reada, bytenr, size);
2541         if (cache) {
2542                 remove_cache_extent(reada, cache);
2543                 free(cache);
2544         }
2545         cache = find_cache_extent(nodes, bytenr, size);
2546         if (cache) {
2547                 remove_cache_extent(nodes, cache);
2548                 free(cache);
2549         }
2550
2551         /* fixme, get the real parent transid */
2552         buf = read_tree_block(root, bytenr, size, 0);
2553         nritems = btrfs_header_nritems(buf);
2554
2555         ret = btrfs_lookup_extent_info(NULL, root, bytenr, size, NULL, &flags);
2556         if (ret < 0)
2557                 flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
2558
2559         if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
2560                 parent = bytenr;
2561                 owner = 0;
2562         } else {
2563                 parent = 0;
2564                 owner = btrfs_header_owner(buf);
2565         }
2566
2567         ret = check_block(root, extent_cache, buf, flags);
2568
2569         if (btrfs_is_leaf(buf)) {
2570                 btree_space_waste += btrfs_leaf_free_space(root, buf);
2571                 for (i = 0; i < nritems; i++) {
2572                         struct btrfs_file_extent_item *fi;
2573                         btrfs_item_key_to_cpu(buf, &key, i);
2574                         if (key.type == BTRFS_EXTENT_ITEM_KEY) {
2575                                 process_extent_item(extent_cache, buf, i);
2576                                 continue;
2577                         }
2578                         if (key.type == BTRFS_EXTENT_CSUM_KEY) {
2579                                 total_csum_bytes +=
2580                                         btrfs_item_size_nr(buf, i);
2581                                 continue;
2582                         }
2583                         if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
2584                                 continue;
2585                         }
2586                         if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
2587 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2588                                 process_extent_ref_v0(extent_cache, buf, i);
2589 #else
2590                                 BUG();
2591 #endif
2592                                 continue;
2593                         }
2594
2595                         if (key.type == BTRFS_TREE_BLOCK_REF_KEY) {
2596                                 add_tree_backref(extent_cache, key.objectid, 0,
2597                                                  key.offset, 0);
2598                                 continue;
2599                         }
2600                         if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) {
2601                                 add_tree_backref(extent_cache, key.objectid,
2602                                                  key.offset, 0, 0);
2603                                 continue;
2604                         }
2605                         if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
2606                                 struct btrfs_extent_data_ref *ref;
2607                                 ref = btrfs_item_ptr(buf, i,
2608                                                 struct btrfs_extent_data_ref);
2609                                 add_data_backref(extent_cache,
2610                                         key.objectid, 0,
2611                                         btrfs_extent_data_ref_root(buf, ref),
2612                                         btrfs_extent_data_ref_objectid(buf,
2613                                                                        ref),
2614                                         btrfs_extent_data_ref_offset(buf, ref),
2615                                         btrfs_extent_data_ref_count(buf, ref),
2616                                         0, root->sectorsize);
2617                                 continue;
2618                         }
2619                         if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
2620                                 struct btrfs_shared_data_ref *ref;
2621                                 ref = btrfs_item_ptr(buf, i,
2622                                                 struct btrfs_shared_data_ref);
2623                                 add_data_backref(extent_cache,
2624                                         key.objectid, key.offset, 0, 0, 0,
2625                                         btrfs_shared_data_ref_count(buf, ref),
2626                                         0, root->sectorsize);
2627                                 continue;
2628                         }
2629                         if (key.type != BTRFS_EXTENT_DATA_KEY)
2630                                 continue;
2631                         fi = btrfs_item_ptr(buf, i,
2632                                             struct btrfs_file_extent_item);
2633                         if (btrfs_file_extent_type(buf, fi) ==
2634                             BTRFS_FILE_EXTENT_INLINE)
2635                                 continue;
2636                         if (btrfs_file_extent_disk_bytenr(buf, fi) == 0)
2637                                 continue;
2638
2639                         data_bytes_allocated +=
2640                                 btrfs_file_extent_disk_num_bytes(buf, fi);
2641                         if (data_bytes_allocated < root->sectorsize) {
2642                                 abort();
2643                         }
2644                         data_bytes_referenced +=
2645                                 btrfs_file_extent_num_bytes(buf, fi);
2646                         ret = add_extent_rec(extent_cache, NULL,
2647                                    btrfs_file_extent_disk_bytenr(buf, fi),
2648                                    btrfs_file_extent_disk_num_bytes(buf, fi),
2649                                    0, 0, 1, 1,
2650                                    btrfs_file_extent_disk_num_bytes(buf, fi));
2651                         add_data_backref(extent_cache,
2652                                 btrfs_file_extent_disk_bytenr(buf, fi),
2653                                 parent, owner, key.objectid, key.offset -
2654                                 btrfs_file_extent_offset(buf, fi), 1, 1,
2655                                 btrfs_file_extent_disk_num_bytes(buf, fi));
2656                         BUG_ON(ret);
2657                 }
2658         } else {
2659                 int level;
2660                 struct btrfs_key first_key;
2661
2662                 first_key.objectid = 0;
2663
2664                 if (nritems > 0)
2665                         btrfs_item_key_to_cpu(buf, &first_key, 0);
2666                 level = btrfs_header_level(buf);
2667                 for (i = 0; i < nritems; i++) {
2668                         u64 ptr = btrfs_node_blockptr(buf, i);
2669                         u32 size = btrfs_level_size(root, level - 1);
2670                         btrfs_node_key_to_cpu(buf, &key, i);
2671                         ret = add_extent_rec(extent_cache, &key,
2672                                              ptr, size, 0, 0, 1, 0, size);
2673                         BUG_ON(ret);
2674
2675                         add_tree_backref(extent_cache, ptr, parent, owner, 1);
2676
2677                         if (level > 1) {
2678                                 add_pending(nodes, seen, ptr, size);
2679                         } else {
2680                                 add_pending(pending, seen, ptr, size);
2681                         }
2682                 }
2683                 btree_space_waste += (BTRFS_NODEPTRS_PER_BLOCK(root) -
2684                                       nritems) * sizeof(struct btrfs_key_ptr);
2685         }
2686         total_btree_bytes += buf->len;
2687         if (fs_root_objectid(btrfs_header_owner(buf)))
2688                 total_fs_tree_bytes += buf->len;
2689         if (!found_old_backref &&
2690             btrfs_header_owner(buf) == BTRFS_TREE_RELOC_OBJECTID &&
2691             btrfs_header_backref_rev(buf) == BTRFS_MIXED_BACKREF_REV &&
2692             !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))
2693                 found_old_backref = 1;
2694         free_extent_buffer(buf);
2695         return 0;
2696 }
2697
2698 static int add_root_to_pending(struct extent_buffer *buf,
2699                                struct block_info *bits,
2700                                int bits_nr,
2701                                struct cache_tree *extent_cache,
2702                                struct cache_tree *pending,
2703                                struct cache_tree *seen,
2704                                struct cache_tree *reada,
2705                                struct cache_tree *nodes,
2706                                struct btrfs_key *root_key)
2707 {
2708         if (btrfs_header_level(buf) > 0)
2709                 add_pending(nodes, seen, buf->start, buf->len);
2710         else
2711                 add_pending(pending, seen, buf->start, buf->len);
2712         add_extent_rec(extent_cache, NULL, buf->start, buf->len,
2713                        0, 1, 1, 0, buf->len);
2714
2715         if (root_key->objectid == BTRFS_TREE_RELOC_OBJECTID ||
2716             btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV)
2717                 add_tree_backref(extent_cache, buf->start, buf->start,
2718                                  0, 1);
2719         else
2720                 add_tree_backref(extent_cache, buf->start, 0,
2721                                  root_key->objectid, 1);
2722         return 0;
2723 }
2724
2725 /* as we fix the tree, we might be deleting blocks that
2726  * we're tracking for repair.  This hook makes sure we
2727  * remove any backrefs for blocks as we are fixing them.
2728  */
2729 static int free_extent_hook(struct btrfs_trans_handle *trans,
2730                             struct btrfs_root *root,
2731                             u64 bytenr, u64 num_bytes, u64 parent,
2732                             u64 root_objectid, u64 owner, u64 offset,
2733                             int refs_to_drop)
2734 {
2735         struct extent_record *rec;
2736         struct cache_extent *cache;
2737         int is_data;
2738         struct cache_tree *extent_cache = root->fs_info->fsck_extent_cache;
2739
2740         is_data = owner >= BTRFS_FIRST_FREE_OBJECTID;
2741         cache = find_cache_extent(extent_cache, bytenr, num_bytes);
2742         if (!cache)
2743                 return 0;
2744
2745         rec = container_of(cache, struct extent_record, cache);
2746         if (is_data) {
2747                 struct data_backref *back;
2748                 back = find_data_backref(rec, parent, root_objectid, owner,
2749                                          offset);
2750                 if (!back)
2751                         goto out;
2752                 if (back->node.found_ref) {
2753                         back->found_ref -= refs_to_drop;
2754                         if (rec->refs)
2755                                 rec->refs -= refs_to_drop;
2756                 }
2757                 if (back->node.found_extent_tree) {
2758                         back->num_refs -= refs_to_drop;
2759                         if (rec->extent_item_refs)
2760                                 rec->extent_item_refs -= refs_to_drop;
2761                 }
2762                 if (back->found_ref == 0)
2763                         back->node.found_ref = 0;
2764                 if (back->num_refs == 0)
2765                         back->node.found_extent_tree = 0;
2766
2767                 if (!back->node.found_extent_tree && back->node.found_ref) {
2768                         list_del(&back->node.list);
2769                         free(back);
2770                 }
2771         } else {
2772                 struct tree_backref *back;
2773                 back = find_tree_backref(rec, parent, root_objectid);
2774                 if (!back)
2775                         goto out;
2776                 if (back->node.found_ref) {
2777                         if (rec->refs)
2778                                 rec->refs--;
2779                         back->node.found_ref = 0;
2780                 }
2781                 if (back->node.found_extent_tree) {
2782                         if (rec->extent_item_refs)
2783                                 rec->extent_item_refs--;
2784                         back->node.found_extent_tree = 0;
2785                 }
2786                 if (!back->node.found_extent_tree && back->node.found_ref) {
2787                         list_del(&back->node.list);
2788                         free(back);
2789                 }
2790         }
2791         maybe_free_extent_rec(extent_cache, rec);
2792 out:
2793         return 0;
2794 }
2795
2796 static int delete_extent_records(struct btrfs_trans_handle *trans,
2797                                  struct btrfs_root *root,
2798                                  struct btrfs_path *path,
2799                                  u64 bytenr, u64 new_len)
2800 {
2801         struct btrfs_key key;
2802         struct btrfs_key found_key;
2803         struct extent_buffer *leaf;
2804         int ret;
2805         int slot;
2806
2807
2808         key.objectid = bytenr;
2809         key.type = (u8)-1;
2810         key.offset = (u64)-1;
2811
2812         while(1) {
2813                 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
2814                                         &key, path, 0, 1);
2815                 if (ret < 0)
2816                         break;
2817
2818                 if (ret > 0) {
2819                         ret = 0;
2820                         if (path->slots[0] == 0)
2821                                 break;
2822                         path->slots[0]--;
2823                 }
2824                 ret = 0;
2825
2826                 leaf = path->nodes[0];
2827                 slot = path->slots[0];
2828
2829                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2830                 if (found_key.objectid != bytenr)
2831                         break;
2832
2833                 if (found_key.type != BTRFS_EXTENT_ITEM_KEY &&
2834                     found_key.type != BTRFS_TREE_BLOCK_REF_KEY &&
2835                     found_key.type != BTRFS_EXTENT_DATA_REF_KEY &&
2836                     found_key.type != BTRFS_EXTENT_REF_V0_KEY &&
2837                     found_key.type != BTRFS_SHARED_BLOCK_REF_KEY &&
2838                     found_key.type != BTRFS_SHARED_DATA_REF_KEY) {
2839                         btrfs_release_path(NULL, path);
2840                         if (found_key.type == 0) {
2841                                 if (found_key.offset == 0)
2842                                         break;
2843                                 key.offset = found_key.offset - 1;
2844                                 key.type = found_key.type;
2845                         }
2846                         key.type = found_key.type - 1;
2847                         key.offset = (u64)-1;
2848                         continue;
2849                 }
2850
2851                 fprintf(stderr, "repair deleting extent record: key %Lu %u %Lu\n",
2852                         found_key.objectid, found_key.type, found_key.offset);
2853
2854                 ret = btrfs_del_item(trans, root->fs_info->extent_root, path);
2855                 if (ret)
2856                         break;
2857                 btrfs_release_path(NULL, path);
2858
2859                 if (found_key.type == BTRFS_EXTENT_ITEM_KEY) {
2860                         ret = btrfs_update_block_group(trans, root, bytenr,
2861                                                        found_key.offset, 0, 0);
2862                         if (ret)
2863                                 break;
2864                 }
2865         }
2866
2867         btrfs_release_path(NULL, path);
2868         return ret;
2869 }
2870
2871 /*
2872  * for a single backref, this will allocate a new extent
2873  * and add the backref to it.
2874  */
2875 static int record_extent(struct btrfs_trans_handle *trans,
2876                          struct btrfs_fs_info *info,
2877                          struct btrfs_path *path,
2878                          struct extent_record *rec,
2879                          struct extent_backref *back,
2880                          int allocated, u64 flags)
2881 {
2882         int ret;
2883         struct btrfs_root *extent_root = info->extent_root;
2884         struct extent_buffer *leaf;
2885         struct btrfs_key ins_key;
2886         struct btrfs_extent_item *ei;
2887         struct tree_backref *tback;
2888         struct data_backref *dback;
2889         struct btrfs_tree_block_info *bi;
2890
2891         if (!back->is_data)
2892                 rec->max_size = max_t(u64, rec->max_size,
2893                                     info->extent_root->leafsize);
2894
2895         if (!allocated) {
2896                 u32 item_size = sizeof(*ei);
2897
2898                 if (!back->is_data)
2899                         item_size += sizeof(*bi);
2900
2901                 ins_key.objectid = rec->start;
2902                 ins_key.offset = rec->max_size;
2903                 ins_key.type = BTRFS_EXTENT_ITEM_KEY;
2904
2905                 ret = btrfs_insert_empty_item(trans, extent_root, path,
2906                                         &ins_key, item_size);
2907                 if (ret)
2908                         goto fail;
2909
2910                 leaf = path->nodes[0];
2911                 ei = btrfs_item_ptr(leaf, path->slots[0],
2912                                     struct btrfs_extent_item);
2913
2914                 btrfs_set_extent_refs(leaf, ei, 0);
2915                 btrfs_set_extent_generation(leaf, ei, rec->generation);
2916
2917                 if (back->is_data) {
2918                         btrfs_set_extent_flags(leaf, ei,
2919                                                BTRFS_EXTENT_FLAG_DATA);
2920                 } else {
2921                         struct btrfs_disk_key copy_key;;
2922
2923                         tback = (struct tree_backref *)back;
2924                         bi = (struct btrfs_tree_block_info *)(ei + 1);
2925                         memset_extent_buffer(leaf, 0, (unsigned long)bi,
2926                                              sizeof(*bi));
2927                         memset(&copy_key, 0, sizeof(copy_key));
2928
2929                         copy_key.objectid = le64_to_cpu(rec->info_objectid);
2930                         btrfs_set_tree_block_level(leaf, bi, rec->info_level);
2931                         btrfs_set_tree_block_key(leaf, bi, &copy_key);
2932
2933                         btrfs_set_extent_flags(leaf, ei,
2934                                                BTRFS_EXTENT_FLAG_TREE_BLOCK | flags);
2935                 }
2936
2937                 btrfs_mark_buffer_dirty(leaf);
2938                 ret = btrfs_update_block_group(trans, extent_root, rec->start,
2939                                                rec->max_size, 1, 0);
2940                 if (ret)
2941                         goto fail;
2942                 btrfs_release_path(NULL, path);
2943         }
2944
2945         if (back->is_data) {
2946                 u64 parent;
2947                 int i;
2948
2949                 dback = (struct data_backref *)back;
2950                 if (back->full_backref)
2951                         parent = dback->parent;
2952                 else
2953                         parent = 0;
2954
2955                 for (i = 0; i < dback->found_ref; i++) {
2956                         /* if parent != 0, we're doing a full backref
2957                          * passing BTRFS_FIRST_FREE_OBJECTID as the owner
2958                          * just makes the backref allocator create a data
2959                          * backref
2960                          */
2961                         ret = btrfs_inc_extent_ref(trans, info->extent_root,
2962                                                    rec->start, rec->max_size,
2963                                                    parent,
2964                                                    dback->root,
2965                                                    parent ?
2966                                                    BTRFS_FIRST_FREE_OBJECTID :
2967                                                    dback->owner,
2968                                                    dback->offset);
2969                         if (ret)
2970                                 break;
2971                 }
2972                 fprintf(stderr, "adding new data backref"
2973                                 " on %llu %s %llu owner %llu"
2974                                 " offset %llu found %d\n",
2975                                 (unsigned long long)rec->start,
2976                                 back->full_backref ?
2977                                 "parent" : "root",
2978                                 back->full_backref ?
2979                                 (unsigned long long)parent :
2980                                 (unsigned long long)dback->root,
2981                                 (unsigned long long)dback->owner,
2982                                 (unsigned long long)dback->offset,
2983                                 dback->found_ref);
2984         } else {
2985                 u64 parent;
2986
2987                 tback = (struct tree_backref *)back;
2988                 if (back->full_backref)
2989                         parent = tback->parent;
2990                 else
2991                         parent = 0;
2992
2993                 ret = btrfs_inc_extent_ref(trans, info->extent_root,
2994                                            rec->start, rec->max_size,
2995                                            parent, tback->root, 0, 0);
2996                 fprintf(stderr, "adding new tree backref on "
2997                         "start %llu len %llu parent %llu root %llu\n",
2998                         rec->start, rec->max_size, tback->parent, tback->root);
2999         }
3000         if (ret)
3001                 goto fail;
3002 fail:
3003         btrfs_release_path(NULL, path);
3004         return ret;
3005 }
3006
3007 /*
3008  * when an incorrect extent item is found, this will delete
3009  * all of the existing entries for it and recreate them
3010  * based on what the tree scan found.
3011  */
3012 static int fixup_extent_refs(struct btrfs_trans_handle *trans,
3013                              struct btrfs_fs_info *info,
3014                              struct extent_record *rec)
3015 {
3016         int ret;
3017         struct btrfs_path *path;
3018         struct list_head *cur = rec->backrefs.next;
3019         struct extent_backref *back;
3020         int allocated = 0;
3021         u64 flags = 0;
3022
3023         /* remember our flags for recreating the extent */
3024         ret = btrfs_lookup_extent_info(NULL, info->extent_root, rec->start,
3025                                        rec->max_size, NULL, &flags);
3026         if (ret < 0)
3027                 flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
3028
3029         path = btrfs_alloc_path();
3030
3031         /* step one, delete all the existing records */
3032         ret = delete_extent_records(trans, info->extent_root, path,
3033                                     rec->start, rec->max_size);
3034
3035         if (ret < 0)
3036                 goto out;
3037
3038         /* step two, recreate all the refs we did find */
3039         while(cur != &rec->backrefs) {
3040                 back = list_entry(cur, struct extent_backref, list);
3041                 cur = cur->next;
3042
3043                 /*
3044                  * if we didn't find any references, don't create a
3045                  * new extent record
3046                  */
3047                 if (!back->found_ref)
3048                         continue;
3049
3050                 ret = record_extent(trans, info, path, rec, back, allocated, flags);
3051                 allocated = 1;
3052
3053                 if (ret)
3054                         goto out;
3055         }
3056 out:
3057         btrfs_free_path(path);
3058         return ret;
3059 }
3060
3061 static int check_extent_refs(struct btrfs_trans_handle *trans,
3062                              struct btrfs_root *root,
3063                              struct cache_tree *extent_cache, int repair)
3064 {
3065         struct extent_record *rec;
3066         struct cache_extent *cache;
3067         int err = 0;
3068         int ret = 0;
3069         int fixed = 0;
3070
3071         if (repair) {
3072                 /*
3073                  * if we're doing a repair, we have to make sure
3074                  * we don't allocate from the problem extents.
3075                  * In the worst case, this will be all the
3076                  * extents in the FS
3077                  */
3078                 cache = find_first_cache_extent(extent_cache, 0);
3079                 while(cache) {
3080                         rec = container_of(cache, struct extent_record, cache);
3081                         btrfs_pin_extent(root->fs_info,
3082                                          rec->start, rec->max_size);
3083                         cache = next_cache_extent(cache);
3084                 }
3085         }
3086         while(1) {
3087                 fixed = 0;
3088                 cache = find_first_cache_extent(extent_cache, 0);
3089                 if (!cache)
3090                         break;
3091                 rec = container_of(cache, struct extent_record, cache);
3092                 if (rec->refs != rec->extent_item_refs) {
3093                         fprintf(stderr, "ref mismatch on [%llu %llu] ",
3094                                 (unsigned long long)rec->start,
3095                                 (unsigned long long)rec->nr);
3096                         fprintf(stderr, "extent item %llu, found %llu\n",
3097                                 (unsigned long long)rec->extent_item_refs,
3098                                 (unsigned long long)rec->refs);
3099                         if (!fixed && repair) {
3100                                 ret = fixup_extent_refs(trans, root->fs_info, rec);
3101                                 if (ret)
3102                                         goto repair_abort;
3103                                 fixed = 1;
3104                         }
3105                         err = 1;
3106
3107                 }
3108                 if (all_backpointers_checked(rec, 1)) {
3109                         fprintf(stderr, "backpointer mismatch on [%llu %llu]\n",
3110                                 (unsigned long long)rec->start,
3111                                 (unsigned long long)rec->nr);
3112
3113                         if (!fixed && repair) {
3114                                 ret = fixup_extent_refs(trans, root->fs_info, rec);
3115                                 if (ret)
3116                                         goto repair_abort;
3117                                 fixed = 1;
3118                         }
3119
3120                         err = 1;
3121                 }
3122                 if (!rec->owner_ref_checked) {
3123                         fprintf(stderr, "owner ref check failed [%llu %llu]\n",
3124                                 (unsigned long long)rec->start,
3125                                 (unsigned long long)rec->nr);
3126                         if (!fixed && repair) {
3127                                 ret = fixup_extent_refs(trans, root->fs_info, rec);
3128                                 if (ret)
3129                                         goto repair_abort;
3130                                 fixed = 1;
3131                         }
3132                         err = 1;
3133                 }
3134
3135                 remove_cache_extent(extent_cache, cache);
3136                 free_all_extent_backrefs(rec);
3137                 free(rec);
3138         }
3139 repair_abort:
3140         if (repair) {
3141                 if (ret) {
3142                         fprintf(stderr, "failed to repair damaged filesystem, aborting\n");
3143                         exit(1);
3144                 } else {
3145                         btrfs_fix_block_accounting(trans, root);
3146                 }
3147                 if (err)
3148                         fprintf(stderr, "repaired damaged extent references\n");
3149                 return ret;
3150         }
3151         return err;
3152 }
3153
3154 static int check_extents(struct btrfs_trans_handle *trans,
3155                          struct btrfs_root *root, int repair)
3156 {
3157         struct cache_tree extent_cache;
3158         struct cache_tree seen;
3159         struct cache_tree pending;
3160         struct cache_tree reada;
3161         struct cache_tree nodes;
3162         struct btrfs_path path;
3163         struct btrfs_key key;
3164         struct btrfs_key found_key;
3165         int ret;
3166         u64 last = 0;
3167         struct block_info *bits;
3168         int bits_nr;
3169         struct extent_buffer *leaf;
3170         int slot;
3171         struct btrfs_root_item ri;
3172
3173         cache_tree_init(&extent_cache);
3174         cache_tree_init(&seen);
3175         cache_tree_init(&pending);
3176         cache_tree_init(&nodes);
3177         cache_tree_init(&reada);
3178
3179         if (repair) {
3180                 root->fs_info->fsck_extent_cache = &extent_cache;
3181                 root->fs_info->free_extent_hook = free_extent_hook;
3182         }
3183
3184         bits_nr = 1024;
3185         bits = malloc(bits_nr * sizeof(struct block_info));
3186         if (!bits) {
3187                 perror("malloc");
3188                 exit(1);
3189         }
3190
3191         add_root_to_pending(root->fs_info->tree_root->node, bits, bits_nr,
3192                             &extent_cache, &pending, &seen, &reada, &nodes,
3193                             &root->fs_info->tree_root->root_key);
3194
3195         add_root_to_pending(root->fs_info->chunk_root->node, bits, bits_nr,
3196                             &extent_cache, &pending, &seen, &reada, &nodes,
3197                             &root->fs_info->chunk_root->root_key);
3198
3199         btrfs_init_path(&path);
3200         key.offset = 0;
3201         key.objectid = 0;
3202         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
3203         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
3204                                         &key, &path, 0, 0);
3205         BUG_ON(ret < 0);
3206         while(1) {
3207                 leaf = path.nodes[0];
3208                 slot = path.slots[0];
3209                 if (slot >= btrfs_header_nritems(path.nodes[0])) {
3210                         ret = btrfs_next_leaf(root, &path);
3211                         if (ret != 0)
3212                                 break;
3213                         leaf = path.nodes[0];
3214                         slot = path.slots[0];
3215                 }
3216                 btrfs_item_key_to_cpu(leaf, &found_key, path.slots[0]);
3217                 if (btrfs_key_type(&found_key) == BTRFS_ROOT_ITEM_KEY) {
3218                         unsigned long offset;
3219                         struct extent_buffer *buf;
3220
3221                         offset = btrfs_item_ptr_offset(leaf, path.slots[0]);
3222                         read_extent_buffer(leaf, &ri, offset, sizeof(ri));
3223                         buf = read_tree_block(root->fs_info->tree_root,
3224                                               btrfs_root_bytenr(&ri),
3225                                               btrfs_level_size(root,
3226                                                btrfs_root_level(&ri)), 0);
3227                         add_root_to_pending(buf, bits, bits_nr, &extent_cache,
3228                                             &pending, &seen, &reada, &nodes,
3229                                             &found_key);
3230                         free_extent_buffer(buf);
3231                 }
3232                 path.slots[0]++;
3233         }
3234         btrfs_release_path(root, &path);
3235         while(1) {
3236                 ret = run_next_block(root, bits, bits_nr, &last, &pending,
3237                                      &seen, &reada, &nodes, &extent_cache);
3238                 if (ret != 0)
3239                         break;
3240         }
3241         ret = check_extent_refs(trans, root, &extent_cache, repair);
3242
3243         if (repair) {
3244                 root->fs_info->fsck_extent_cache = NULL;
3245                 root->fs_info->free_extent_hook = NULL;
3246         }
3247
3248         return ret;
3249 }
3250
3251 static void print_usage(void)
3252 {
3253         fprintf(stderr, "usage: btrfsck dev\n");
3254         fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
3255         exit(1);
3256 }
3257
3258 static struct option long_options[] = {
3259         { "super", 1, NULL, 's' },
3260         { "repair", 0, NULL, 0 },
3261         { "init-csum-tree", 0, NULL, 0 },
3262         { 0, 0, 0, 0}
3263 };
3264
3265 int main(int ac, char **av)
3266 {
3267         struct cache_tree root_cache;
3268         struct btrfs_root *root;
3269         struct btrfs_fs_info *info;
3270         struct btrfs_trans_handle *trans = NULL;
3271         u64 bytenr = 0;
3272         int ret;
3273         int num;
3274         int repair = 0;
3275         int option_index = 0;
3276         int init_csum_tree = 0;
3277         int rw = 0;
3278
3279         while(1) {
3280                 int c;
3281                 c = getopt_long(ac, av, "", long_options,
3282                                 &option_index);
3283                 if (c < 0)
3284                         break;
3285                 switch(c) {
3286                         case 's':
3287                                 num = atol(optarg);
3288                                 bytenr = btrfs_sb_offset(num);
3289                                 printf("using SB copy %d, bytenr %llu\n", num,
3290                                        (unsigned long long)bytenr);
3291                                 break;
3292                         case '?':
3293                                 print_usage();
3294                 }
3295                 if (option_index == 1) {
3296                         printf("enabling repair mode\n");
3297                         repair = 1;
3298                         rw = 1;
3299                 } else if (option_index == 2) {
3300                         printf("Creating a new CRC tree\n");
3301                         init_csum_tree = 1;
3302                         rw = 1;
3303                 }
3304
3305         }
3306         ac = ac - optind;
3307
3308         if (ac != 1)
3309                 print_usage();
3310
3311         radix_tree_init();
3312         cache_tree_init(&root_cache);
3313
3314         if((ret = check_mounted(av[optind])) < 0) {
3315                 fprintf(stderr, "Could not check mount status: %s\n", strerror(-ret));
3316                 return ret;
3317         } else if(ret) {
3318                 fprintf(stderr, "%s is currently mounted. Aborting.\n", av[optind]);
3319                 return -EBUSY;
3320         }
3321
3322         info = open_ctree_fs_info(av[optind], bytenr, rw, 1);
3323
3324         if (info == NULL)
3325                 return 1;
3326
3327         if (!extent_buffer_uptodate(info->tree_root->node) ||
3328             !extent_buffer_uptodate(info->dev_root->node) ||
3329             !extent_buffer_uptodate(info->extent_root->node) ||
3330             !extent_buffer_uptodate(info->chunk_root->node)) {
3331                 fprintf(stderr, "Critical roots corrupted, unable to fsck the FS\n");
3332                 return -EIO;
3333         }
3334
3335         root = info->fs_root;
3336
3337         fprintf(stderr, "checking extents\n");
3338         if (rw)
3339                 trans = btrfs_start_transaction(root, 1);
3340
3341         if (init_csum_tree) {
3342                 fprintf(stderr, "Reinit crc root\n");
3343                 ret = btrfs_fsck_reinit_root(trans, info->csum_root);
3344                 if (ret) {
3345                         fprintf(stderr, "crc root initialization failed\n");
3346                         return -EIO;
3347                 }
3348                 goto out;
3349         }
3350
3351         ret = check_extents(trans, root, repair);
3352         if (ret)
3353                 fprintf(stderr, "Errors found in extent allocation tree\n");
3354
3355         fprintf(stderr, "checking fs roots\n");
3356         ret = check_fs_roots(root, &root_cache);
3357         if (ret)
3358                 goto out;
3359
3360         fprintf(stderr, "checking root refs\n");
3361         ret = check_root_refs(root, &root_cache);
3362 out:
3363         free_root_recs(&root_cache);
3364         if (rw) {
3365                 ret = btrfs_commit_transaction(trans, root);
3366                 if (ret)
3367                         exit(1);
3368         }
3369         close_ctree(root);
3370
3371         if (found_old_backref) { /*
3372                  * there was a disk format change when mixed
3373                  * backref was in testing tree. The old format
3374                  * existed about one week.
3375                  */
3376                 printf("\n * Found old mixed backref format. "
3377                        "The old format is not supported! *"
3378                        "\n * Please mount the FS in readonly mode, "
3379                        "backup data and re-format the FS. *\n\n");
3380                 ret = 1;
3381         }
3382         printf("found %llu bytes used err is %d\n",
3383                (unsigned long long)bytes_used, ret);
3384         printf("total csum bytes: %llu\n",(unsigned long long)total_csum_bytes);
3385         printf("total tree bytes: %llu\n",
3386                (unsigned long long)total_btree_bytes);
3387         printf("total fs tree bytes: %llu\n",
3388                (unsigned long long)total_fs_tree_bytes);
3389         printf("btree space waste bytes: %llu\n",
3390                (unsigned long long)btree_space_waste);
3391         printf("file data blocks allocated: %llu\n referenced %llu\n",
3392                 (unsigned long long)data_bytes_allocated,
3393                 (unsigned long long)data_bytes_referenced);
3394         printf("%s\n", BTRFS_BUILD_VERSION);
3395         return ret;
3396 }