disk-io.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include <uuid/uuid.h>
  26 #include "kerncompat.h"
  27 #include "radix-tree.h"
  28 #include "ctree.h"
  29 #include "disk-io.h"
  30 #include "volumes.h"
  31 #include "transaction.h"
  32 #include "crc32c.h"
  33 #include "utils.h"
  34 #include "print-tree.h"
  35 #include "rbtree-utils.h"
  36
  37 /* specified errno for check_tree_block */
  38 #define BTRFS_BAD_BYTENR                (-1)
  39 #define BTRFS_BAD_FSID                  (-2)
  40 #define BTRFS_BAD_LEVEL                 (-3)
  41 #define BTRFS_BAD_NRITEMS               (-4)
  42
  43 /* Calculate max possible nritems for a leaf/node */
  44 static u32 max_nritems(u8 level, u32 nodesize)
  45 {
  46
  47         if (level == 0)
  48                 return ((nodesize - sizeof(struct btrfs_header)) /
  49                         sizeof(struct btrfs_item));
  50         return ((nodesize - sizeof(struct btrfs_header)) /
  51                 sizeof(struct btrfs_key_ptr));
  52 }
  53
  54 static int check_tree_block(struct btrfs_fs_info *fs_info,
  55                             struct extent_buffer *buf)
  56 {
  57
  58         struct btrfs_fs_devices *fs_devices;
  59         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
  60         int ret = BTRFS_BAD_FSID;
  61
  62         if (buf->start != btrfs_header_bytenr(buf))
  63                 return BTRFS_BAD_BYTENR;
  64         if (btrfs_header_level(buf) >= BTRFS_MAX_LEVEL)
  65                 return BTRFS_BAD_LEVEL;
  66         if (btrfs_header_nritems(buf) > max_nritems(btrfs_header_level(buf),
  67                                                     nodesize))
  68                 return BTRFS_BAD_NRITEMS;
  69
  70         /* Only leaf can be empty */
  71         if (btrfs_header_nritems(buf) == 0 &&
  72             btrfs_header_level(buf) != 0)
  73                 return BTRFS_BAD_NRITEMS;
  74
  75         fs_devices = fs_info->fs_devices;
  76         while (fs_devices) {
  77                 if (fs_info->ignore_fsid_mismatch ||
  78                     !memcmp_extent_buffer(buf, fs_devices->fsid,
  79                                           btrfs_header_fsid(),
  80                                           BTRFS_FSID_SIZE)) {
  81                         ret = 0;
  82                         break;
  83                 }
  84                 fs_devices = fs_devices->seed;
  85         }
  86         return ret;
  87 }
  88
  89 static void print_tree_block_error(struct btrfs_fs_info *fs_info,
  90                                 struct extent_buffer *eb,
  91                                 int err)
  92 {
  93         char fs_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
  94         char found_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
  95         u8 buf[BTRFS_UUID_SIZE];
  96
  97         switch (err) {
  98         case BTRFS_BAD_FSID:
  99                 read_extent_buffer(eb, buf, btrfs_header_fsid(),
 100                                    BTRFS_UUID_SIZE);
 101                 uuid_unparse(buf, found_uuid);
 102                 uuid_unparse(fs_info->fsid, fs_uuid);
 103                 fprintf(stderr, "fsid mismatch, want=%s, have=%s\n",
 104                         fs_uuid, found_uuid);
 105                 break;
 106         case BTRFS_BAD_BYTENR:
 107                 fprintf(stderr, "bytenr mismatch, want=%llu, have=%llu\n",
 108                         eb->start, btrfs_header_bytenr(eb));
 109                 break;
 110         case BTRFS_BAD_LEVEL:
 111                 fprintf(stderr, "bad level, %u > %u\n",
 112                         btrfs_header_level(eb), BTRFS_MAX_LEVEL);
 113                 break;
 114         case BTRFS_BAD_NRITEMS:
 115                 fprintf(stderr, "invalid nr_items: %u\n",
 116                         btrfs_header_nritems(eb));
 117                 break;
 118         }
 119 }
 120
 121 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
 122 {
 123         return crc32c(seed, data, len);
 124 }
 125
 126 void btrfs_csum_final(u32 crc, u8 *result)
 127 {
 128         put_unaligned_le32(~crc, result);
 129 }
 130
 131 static int __csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
 132                                   int verify, int silent)
 133 {
 134         u8 result[BTRFS_CSUM_SIZE];
 135         u32 len;
 136         u32 crc = ~(u32)0;
 137
 138         len = buf->len - BTRFS_CSUM_SIZE;
 139         crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len);
 140         btrfs_csum_final(crc, result);
 141
 142         if (verify) {
 143                 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
 144                         if (!silent)
 145                                 printk("checksum verify failed on %llu found %08X wanted %08X\n",
 146                                        (unsigned long long)buf->start,
 147                                        *((u32 *)result),
 148                                        *((u32*)(char *)buf->data));
 149                         return 1;
 150                 }
 151         } else {
 152                 write_extent_buffer(buf, result, 0, csum_size);
 153         }
 154         return 0;
 155 }
 156
 157 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size, int verify)
 158 {
 159         return __csum_tree_block_size(buf, csum_size, verify, 0);
 160 }
 161
 162 int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size)
 163 {
 164         return __csum_tree_block_size(buf, csum_size, 1, 1);
 165 }
 166
 167 static int csum_tree_block_fs_info(struct btrfs_fs_info *fs_info,
 168                                    struct extent_buffer *buf, int verify)
 169 {
 170         u16 csum_size =
 171                 btrfs_super_csum_size(fs_info->super_copy);
 172         if (verify && fs_info->suppress_check_block_errors)
 173                 return verify_tree_block_csum_silent(buf, csum_size);
 174         return csum_tree_block_size(buf, csum_size, verify);
 175 }
 176
 177 int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 178                            int verify)
 179 {
 180         return csum_tree_block_fs_info(root->fs_info, buf, verify);
 181 }
 182
 183 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
 184                                             u64 bytenr, u32 blocksize)
 185 {
 186         return find_extent_buffer(&root->fs_info->extent_cache,
 187                                   bytenr, blocksize);
 188 }
 189
 190 struct extent_buffer* btrfs_find_create_tree_block(
 191                 struct btrfs_fs_info *fs_info, u64 bytenr, u32 blocksize)
 192 {
 193         return alloc_extent_buffer(&fs_info->extent_cache, bytenr, blocksize);
 194 }
 195
 196 void readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
 197                           u64 parent_transid)
 198 {
 199         struct extent_buffer *eb;
 200         u64 length;
 201         struct btrfs_multi_bio *multi = NULL;
 202         struct btrfs_device *device;
 203
 204         eb = btrfs_find_tree_block(root, bytenr, blocksize);
 205         if (!(eb && btrfs_buffer_uptodate(eb, parent_transid)) &&
 206             !btrfs_map_block(&root->fs_info->mapping_tree, READ,
 207                              bytenr, &length, &multi, 0, NULL)) {
 208                 device = multi->stripes[0].dev;
 209                 device->total_ios++;
 210                 blocksize = min(blocksize, (u32)(64 * 1024));
 211                 readahead(device->fd, multi->stripes[0].physical, blocksize);
 212         }
 213
 214         free_extent_buffer(eb);
 215         kfree(multi);
 216 }
 217
 218 static int verify_parent_transid(struct extent_io_tree *io_tree,
 219                                  struct extent_buffer *eb, u64 parent_transid,
 220                                  int ignore)
 221 {
 222         int ret;
 223
 224         if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 225                 return 0;
 226
 227         if (extent_buffer_uptodate(eb) &&
 228             btrfs_header_generation(eb) == parent_transid) {
 229                 ret = 0;
 230                 goto out;
 231         }
 232         printk("parent transid verify failed on %llu wanted %llu found %llu\n",
 233                (unsigned long long)eb->start,
 234                (unsigned long long)parent_transid,
 235                (unsigned long long)btrfs_header_generation(eb));
 236         if (ignore) {
 237                 eb->flags |= EXTENT_BAD_TRANSID;
 238                 printk("Ignoring transid failure\n");
 239                 return 0;
 240         }
 241
 242         ret = 1;
 243 out:
 244         clear_extent_buffer_uptodate(eb);
 245         return ret;
 246
 247 }
 248
 249
 250 int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror)
 251 {
 252         unsigned long offset = 0;
 253         struct btrfs_multi_bio *multi = NULL;
 254         struct btrfs_device *device;
 255         int ret = 0;
 256         u64 read_len;
 257         unsigned long bytes_left = eb->len;
 258
 259         while (bytes_left) {
 260                 read_len = bytes_left;
 261                 device = NULL;
 262
 263                 if (!info->on_restoring &&
 264                     eb->start != BTRFS_SUPER_INFO_OFFSET) {
 265                         ret = btrfs_map_block(&info->mapping_tree, READ,
 266                                               eb->start + offset, &read_len, &multi,
 267                                               mirror, NULL);
 268                         if (ret) {
 269                                 printk("Couldn't map the block %Lu\n", eb->start + offset);
 270                                 kfree(multi);
 271                                 return -EIO;
 272                         }
 273                         device = multi->stripes[0].dev;
 274
 275                         if (device->fd <= 0) {
 276                                 kfree(multi);
 277                                 return -EIO;
 278                         }
 279
 280                         eb->fd = device->fd;
 281                         device->total_ios++;
 282                         eb->dev_bytenr = multi->stripes[0].physical;
 283                         kfree(multi);
 284                         multi = NULL;
 285                 } else {
 286                         /* special case for restore metadump */
 287                         list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
 288                                 if (device->devid == 1)
 289                                         break;
 290                         }
 291
 292                         eb->fd = device->fd;
 293                         eb->dev_bytenr = eb->start;
 294                         device->total_ios++;
 295                 }
 296
 297                 if (read_len > bytes_left)
 298                         read_len = bytes_left;
 299
 300                 ret = read_extent_from_disk(eb, offset, read_len);
 301                 if (ret)
 302                         return -EIO;
 303                 offset += read_len;
 304                 bytes_left -= read_len;
 305         }
 306         return 0;
 307 }
 308
 309 struct extent_buffer* read_tree_block_fs_info(
 310                 struct btrfs_fs_info *fs_info, u64 bytenr, u32 blocksize,
 311                 u64 parent_transid)
 312 {
 313         int ret;
 314         struct extent_buffer *eb;
 315         u64 best_transid = 0;
 316         u32 sectorsize = btrfs_super_sectorsize(fs_info->super_copy);
 317         u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
 318         int mirror_num = 0;
 319         int good_mirror = 0;
 320         int num_copies;
 321         int ignore = 0;
 322
 323         /*
 324          * Don't even try to create tree block for unaligned tree block
 325          * bytenr.
 326          * Such unaligned tree block will free overlapping extent buffer,
 327          * causing use-after-free bugs for fuzzed images.
 328          */
 329         if (bytenr < sectorsize || !IS_ALIGNED(bytenr, sectorsize)) {
 330                 error("tree block bytenr %llu is not aligned to sectorsize %u",
 331                       bytenr, sectorsize);
 332                 return ERR_PTR(-EIO);
 333         }
 334         if (blocksize < nodesize || !IS_ALIGNED(blocksize, nodesize)) {
 335                 error("tree block size %u is not aligned to nodesize %u",
 336                       blocksize, nodesize);
 337                 return ERR_PTR(-EIO);
 338         }
 339
 340         eb = btrfs_find_create_tree_block(fs_info, bytenr, blocksize);
 341         if (!eb)
 342                 return ERR_PTR(-ENOMEM);
 343
 344         if (btrfs_buffer_uptodate(eb, parent_transid))
 345                 return eb;
 346
 347         while (1) {
 348                 ret = read_whole_eb(fs_info, eb, mirror_num);
 349                 if (ret == 0 && csum_tree_block_fs_info(fs_info, eb, 1) == 0 &&
 350                     check_tree_block(fs_info, eb) == 0 &&
 351                     verify_parent_transid(eb->tree, eb, parent_transid, ignore)
 352                     == 0) {
 353                         if (eb->flags & EXTENT_BAD_TRANSID &&
 354                             list_empty(&eb->recow)) {
 355                                 list_add_tail(&eb->recow,
 356                                               &fs_info->recow_ebs);
 357                                 eb->refs++;
 358                         }
 359                         btrfs_set_buffer_uptodate(eb);
 360                         return eb;
 361                 }
 362                 if (ignore) {
 363                         if (check_tree_block(fs_info, eb)) {
 364                                 if (!fs_info->suppress_check_block_errors)
 365                                         print_tree_block_error(fs_info, eb,
 366                                                 check_tree_block(fs_info, eb));
 367                         } else {
 368                                 if (!fs_info->suppress_check_block_errors)
 369                                         fprintf(stderr, "Csum didn't match\n");
 370                         }
 371                         ret = -EIO;
 372                         break;
 373                 }
 374                 num_copies = btrfs_num_copies(&fs_info->mapping_tree,
 375                                               eb->start, eb->len);
 376                 if (num_copies == 1) {
 377                         ignore = 1;
 378                         continue;
 379                 }
 380                 if (btrfs_header_generation(eb) > best_transid && mirror_num) {
 381                         best_transid = btrfs_header_generation(eb);
 382                         good_mirror = mirror_num;
 383                 }
 384                 mirror_num++;
 385                 if (mirror_num > num_copies) {
 386                         mirror_num = good_mirror;
 387                         ignore = 1;
 388                         continue;
 389                 }
 390         }
 391         free_extent_buffer(eb);
 392         return ERR_PTR(ret);
 393 }
 394
 395 int read_extent_data(struct btrfs_root *root, char *data,
 396                            u64 logical, u64 *len, int mirror)
 397 {
 398         u64 offset = 0;
 399         struct btrfs_multi_bio *multi = NULL;
 400         struct btrfs_fs_info *info = root->fs_info;
 401         struct btrfs_device *device;
 402         int ret = 0;
 403         u64 max_len = *len;
 404
 405         ret = btrfs_map_block(&info->mapping_tree, READ, logical, len,
 406                               &multi, mirror, NULL);
 407         if (ret) {
 408                 fprintf(stderr, "Couldn't map the block %llu\n",
 409                                 logical + offset);
 410                 goto err;
 411         }
 412         device = multi->stripes[0].dev;
 413
 414         if (device->fd <= 0)
 415                 goto err;
 416         if (*len > max_len)
 417                 *len = max_len;
 418
 419         ret = pread64(device->fd, data, *len, multi->stripes[0].physical);
 420         if (ret != *len)
 421                 ret = -EIO;
 422         else
 423                 ret = 0;
 424 err:
 425         kfree(multi);
 426         return ret;
 427 }
 428
 429 int write_and_map_eb(struct btrfs_trans_handle *trans,
 430                      struct btrfs_root *root,
 431                      struct extent_buffer *eb)
 432 {
 433         int ret;
 434         int dev_nr;
 435         u64 length;
 436         u64 *raid_map = NULL;
 437         struct btrfs_multi_bio *multi = NULL;
 438
 439         dev_nr = 0;
 440         length = eb->len;
 441         ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE,
 442                               eb->start, &length, &multi, 0, &raid_map);
 443
 444         if (raid_map) {
 445                 ret = write_raid56_with_parity(root->fs_info, eb, multi,
 446                                                length, raid_map);
 447                 BUG_ON(ret);
 448         } else while (dev_nr < multi->num_stripes) {
 449                 BUG_ON(ret);
 450                 eb->fd = multi->stripes[dev_nr].dev->fd;
 451                 eb->dev_bytenr = multi->stripes[dev_nr].physical;
 452                 multi->stripes[dev_nr].dev->total_ios++;
 453                 dev_nr++;
 454                 ret = write_extent_to_disk(eb);
 455                 BUG_ON(ret);
 456         }
 457         kfree(raid_map);
 458         kfree(multi);
 459         return 0;
 460 }
 461
 462 int write_tree_block(struct btrfs_trans_handle *trans,
 463                      struct btrfs_root *root,
 464                      struct extent_buffer *eb)
 465 {
 466         if (check_tree_block(root->fs_info, eb)) {
 467                 print_tree_block_error(root->fs_info, eb,
 468                                 check_tree_block(root->fs_info, eb));
 469                 BUG();
 470         }
 471
 472         if (trans && !btrfs_buffer_uptodate(eb, trans->transid))
 473                 BUG();
 474
 475         btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
 476         csum_tree_block(root, eb, 0);
 477
 478         return write_and_map_eb(trans, root, eb);
 479 }
 480
 481 int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 482                         u32 stripesize, struct btrfs_root *root,
 483                         struct btrfs_fs_info *fs_info, u64 objectid)
 484 {
 485         root->node = NULL;
 486         root->commit_root = NULL;
 487         root->sectorsize = sectorsize;
 488         root->nodesize = nodesize;
 489         root->leafsize = leafsize;
 490         root->stripesize = stripesize;
 491         root->ref_cows = 0;
 492         root->track_dirty = 0;
 493
 494         root->fs_info = fs_info;
 495         root->objectid = objectid;
 496         root->last_trans = 0;
 497         root->highest_inode = 0;
 498         root->last_inode_alloc = 0;
 499
 500         INIT_LIST_HEAD(&root->dirty_list);
 501         INIT_LIST_HEAD(&root->orphan_data_extents);
 502         memset(&root->root_key, 0, sizeof(root->root_key));
 503         memset(&root->root_item, 0, sizeof(root->root_item));
 504         root->root_key.objectid = objectid;
 505         return 0;
 506 }
 507
 508 static int update_cowonly_root(struct btrfs_trans_handle *trans,
 509                                struct btrfs_root *root)
 510 {
 511         int ret;
 512         u64 old_root_bytenr;
 513         struct btrfs_root *tree_root = root->fs_info->tree_root;
 514
 515         btrfs_write_dirty_block_groups(trans, root);
 516         while(1) {
 517                 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
 518                 if (old_root_bytenr == root->node->start)
 519                         break;
 520                 btrfs_set_root_bytenr(&root->root_item,
 521                                        root->node->start);
 522                 btrfs_set_root_generation(&root->root_item,
 523                                           trans->transid);
 524                 root->root_item.level = btrfs_header_level(root->node);
 525                 ret = btrfs_update_root(trans, tree_root,
 526                                         &root->root_key,
 527                                         &root->root_item);
 528                 BUG_ON(ret);
 529                 btrfs_write_dirty_block_groups(trans, root);
 530         }
 531         return 0;
 532 }
 533
 534 static int commit_tree_roots(struct btrfs_trans_handle *trans,
 535                              struct btrfs_fs_info *fs_info)
 536 {
 537         struct btrfs_root *root;
 538         struct list_head *next;
 539         struct extent_buffer *eb;
 540         int ret;
 541
 542         if (fs_info->readonly)
 543                 return 0;
 544
 545         eb = fs_info->tree_root->node;
 546         extent_buffer_get(eb);
 547         ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
 548         free_extent_buffer(eb);
 549         if (ret)
 550                 return ret;
 551
 552         while(!list_empty(&fs_info->dirty_cowonly_roots)) {
 553                 next = fs_info->dirty_cowonly_roots.next;
 554                 list_del_init(next);
 555                 root = list_entry(next, struct btrfs_root, dirty_list);
 556                 update_cowonly_root(trans, root);
 557                 free_extent_buffer(root->commit_root);
 558                 root->commit_root = NULL;
 559         }
 560
 561         return 0;
 562 }
 563
 564 static int __commit_transaction(struct btrfs_trans_handle *trans,
 565                                 struct btrfs_root *root)
 566 {
 567         u64 start;
 568         u64 end;
 569         struct extent_buffer *eb;
 570         struct extent_io_tree *tree = &root->fs_info->extent_cache;
 571         int ret;
 572
 573         while(1) {
 574                 ret = find_first_extent_bit(tree, 0, &start, &end,
 575                                             EXTENT_DIRTY);
 576                 if (ret)
 577                         break;
 578                 while(start <= end) {
 579                         eb = find_first_extent_buffer(tree, start);
 580                         BUG_ON(!eb || eb->start != start);
 581                         ret = write_tree_block(trans, root, eb);
 582                         BUG_ON(ret);
 583                         start += eb->len;
 584                         clear_extent_buffer_dirty(eb);
 585                         free_extent_buffer(eb);
 586                 }
 587         }
 588         return 0;
 589 }
 590
 591 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 592                              struct btrfs_root *root)
 593 {
 594         u64 transid = trans->transid;
 595         int ret = 0;
 596         struct btrfs_fs_info *fs_info = root->fs_info;
 597
 598         if (root->commit_root == root->node)
 599                 goto commit_tree;
 600         if (root == root->fs_info->tree_root)
 601                 goto commit_tree;
 602         if (root == root->fs_info->chunk_root)
 603                 goto commit_tree;
 604
 605         free_extent_buffer(root->commit_root);
 606         root->commit_root = NULL;
 607
 608         btrfs_set_root_bytenr(&root->root_item, root->node->start);
 609         btrfs_set_root_generation(&root->root_item, trans->transid);
 610         root->root_item.level = btrfs_header_level(root->node);
 611         ret = btrfs_update_root(trans, root->fs_info->tree_root,
 612                                 &root->root_key, &root->root_item);
 613         BUG_ON(ret);
 614 commit_tree:
 615         ret = commit_tree_roots(trans, fs_info);
 616         BUG_ON(ret);
 617         ret = __commit_transaction(trans, root);
 618         BUG_ON(ret);
 619         write_ctree_super(trans, root);
 620         btrfs_finish_extent_commit(trans, fs_info->extent_root,
 621                                    &fs_info->pinned_extents);
 622         btrfs_free_transaction(root, trans);
 623         free_extent_buffer(root->commit_root);
 624         root->commit_root = NULL;
 625         fs_info->running_transaction = NULL;
 626         fs_info->last_trans_committed = transid;
 627         return 0;
 628 }
 629
 630 static int find_and_setup_root(struct btrfs_root *tree_root,
 631                                struct btrfs_fs_info *fs_info,
 632                                u64 objectid, struct btrfs_root *root)
 633 {
 634         int ret;
 635         u32 blocksize;
 636         u64 generation;
 637
 638         __setup_root(tree_root->nodesize, tree_root->leafsize,
 639                      tree_root->sectorsize, tree_root->stripesize,
 640                      root, fs_info, objectid);
 641         ret = btrfs_find_last_root(tree_root, objectid,
 642                                    &root->root_item, &root->root_key);
 643         if (ret)
 644                 return ret;
 645
 646         blocksize = root->nodesize;
 647         generation = btrfs_root_generation(&root->root_item);
 648         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 649                                      blocksize, generation);
 650         if (!extent_buffer_uptodate(root->node))
 651                 return -EIO;
 652
 653         return 0;
 654 }
 655
 656 static int find_and_setup_log_root(struct btrfs_root *tree_root,
 657                                struct btrfs_fs_info *fs_info,
 658                                struct btrfs_super_block *disk_super)
 659 {
 660         u32 blocksize;
 661         u64 blocknr = btrfs_super_log_root(disk_super);
 662         struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
 663
 664         if (!log_root)
 665                 return -ENOMEM;
 666
 667         if (blocknr == 0) {
 668                 free(log_root);
 669                 return 0;
 670         }
 671
 672         blocksize = tree_root->nodesize;
 673
 674         __setup_root(tree_root->nodesize, tree_root->leafsize,
 675                      tree_root->sectorsize, tree_root->stripesize,
 676                      log_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
 677
 678         log_root->node = read_tree_block(tree_root, blocknr,
 679                                      blocksize,
 680                                      btrfs_super_generation(disk_super) + 1);
 681
 682         fs_info->log_root_tree = log_root;
 683
 684         if (!extent_buffer_uptodate(log_root->node)) {
 685                 free_extent_buffer(log_root->node);
 686                 free(log_root);
 687                 fs_info->log_root_tree = NULL;
 688                 return -EIO;
 689         }
 690
 691         return 0;
 692 }
 693
 694 int btrfs_free_fs_root(struct btrfs_root *root)
 695 {
 696         if (root->node)
 697                 free_extent_buffer(root->node);
 698         if (root->commit_root)
 699                 free_extent_buffer(root->commit_root);
 700         kfree(root);
 701         return 0;
 702 }
 703
 704 static void __free_fs_root(struct rb_node *node)
 705 {
 706         struct btrfs_root *root;
 707
 708         root = container_of(node, struct btrfs_root, rb_node);
 709         btrfs_free_fs_root(root);
 710 }
 711
 712 FREE_RB_BASED_TREE(fs_roots, __free_fs_root);
 713
 714 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
 715                                                struct btrfs_key *location)
 716 {
 717         struct btrfs_root *root;
 718         struct btrfs_root *tree_root = fs_info->tree_root;
 719         struct btrfs_path *path;
 720         struct extent_buffer *l;
 721         u64 generation;
 722         u32 blocksize;
 723         int ret = 0;
 724
 725         root = calloc(1, sizeof(*root));
 726         if (!root)
 727                 return ERR_PTR(-ENOMEM);
 728         if (location->offset == (u64)-1) {
 729                 ret = find_and_setup_root(tree_root, fs_info,
 730                                           location->objectid, root);
 731                 if (ret) {
 732                         free(root);
 733                         return ERR_PTR(ret);
 734                 }
 735                 goto insert;
 736         }
 737
 738         __setup_root(tree_root->nodesize, tree_root->leafsize,
 739                      tree_root->sectorsize, tree_root->stripesize,
 740                      root, fs_info, location->objectid);
 741
 742         path = btrfs_alloc_path();
 743         if (!path) {
 744                 free(root);
 745                 return ERR_PTR(-ENOMEM);
 746         }
 747
 748         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
 749         if (ret != 0) {
 750                 if (ret > 0)
 751                         ret = -ENOENT;
 752                 goto out;
 753         }
 754         l = path->nodes[0];
 755         read_extent_buffer(l, &root->root_item,
 756                btrfs_item_ptr_offset(l, path->slots[0]),
 757                sizeof(root->root_item));
 758         memcpy(&root->root_key, location, sizeof(*location));
 759         ret = 0;
 760 out:
 761         btrfs_free_path(path);
 762         if (ret) {
 763                 free(root);
 764                 return ERR_PTR(ret);
 765         }
 766         generation = btrfs_root_generation(&root->root_item);
 767         blocksize = root->nodesize;
 768         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 769                                      blocksize, generation);
 770         if (!extent_buffer_uptodate(root->node)) {
 771                 free(root);
 772                 return ERR_PTR(-EIO);
 773         }
 774 insert:
 775         root->ref_cows = 1;
 776         return root;
 777 }
 778
 779 static int btrfs_fs_roots_compare_objectids(struct rb_node *node,
 780                                             void *data)
 781 {
 782         u64 objectid = *((u64 *)data);
 783         struct btrfs_root *root;
 784
 785         root = rb_entry(node, struct btrfs_root, rb_node);
 786         if (objectid > root->objectid)
 787                 return 1;
 788         else if (objectid < root->objectid)
 789                 return -1;
 790         else
 791                 return 0;
 792 }
 793
 794 static int btrfs_fs_roots_compare_roots(struct rb_node *node1,
 795                                         struct rb_node *node2)
 796 {
 797         struct btrfs_root *root;
 798
 799         root = rb_entry(node2, struct btrfs_root, rb_node);
 800         return btrfs_fs_roots_compare_objectids(node1, (void *)&root->objectid);
 801 }
 802
 803 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 804                                       struct btrfs_key *location)
 805 {
 806         struct btrfs_root *root;
 807         struct rb_node *node;
 808         int ret;
 809         u64 objectid = location->objectid;
 810
 811         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
 812                 return fs_info->tree_root;
 813         if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
 814                 return fs_info->extent_root;
 815         if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
 816                 return fs_info->chunk_root;
 817         if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
 818                 return fs_info->dev_root;
 819         if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
 820                 return fs_info->csum_root;
 821         if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
 822                 return fs_info->quota_root;
 823
 824         BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
 825                location->offset != (u64)-1);
 826
 827         node = rb_search(&fs_info->fs_root_tree, (void *)&objectid,
 828                          btrfs_fs_roots_compare_objectids, NULL);
 829         if (node)
 830                 return container_of(node, struct btrfs_root, rb_node);
 831
 832         root = btrfs_read_fs_root_no_cache(fs_info, location);
 833         if (IS_ERR(root))
 834                 return root;
 835
 836         ret = rb_insert(&fs_info->fs_root_tree, &root->rb_node,
 837                         btrfs_fs_roots_compare_roots);
 838         BUG_ON(ret);
 839         return root;
 840 }
 841
 842 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
 843 {
 844         free(fs_info->tree_root);
 845         free(fs_info->extent_root);
 846         free(fs_info->chunk_root);
 847         free(fs_info->dev_root);
 848         free(fs_info->csum_root);
 849         free(fs_info->quota_root);
 850         free(fs_info->free_space_root);
 851         free(fs_info->super_copy);
 852         free(fs_info->log_root_tree);
 853         free(fs_info);
 854 }
 855
 856 struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr)
 857 {
 858         struct btrfs_fs_info *fs_info;
 859
 860         fs_info = calloc(1, sizeof(struct btrfs_fs_info));
 861         if (!fs_info)
 862                 return NULL;
 863
 864         fs_info->tree_root = calloc(1, sizeof(struct btrfs_root));
 865         fs_info->extent_root = calloc(1, sizeof(struct btrfs_root));
 866         fs_info->chunk_root = calloc(1, sizeof(struct btrfs_root));
 867         fs_info->dev_root = calloc(1, sizeof(struct btrfs_root));
 868         fs_info->csum_root = calloc(1, sizeof(struct btrfs_root));
 869         fs_info->quota_root = calloc(1, sizeof(struct btrfs_root));
 870         fs_info->free_space_root = calloc(1, sizeof(struct btrfs_root));
 871         fs_info->super_copy = calloc(1, BTRFS_SUPER_INFO_SIZE);
 872
 873         if (!fs_info->tree_root || !fs_info->extent_root ||
 874             !fs_info->chunk_root || !fs_info->dev_root ||
 875             !fs_info->csum_root || !fs_info->quota_root ||
 876             !fs_info->free_space_root || !fs_info->super_copy)
 877                 goto free_all;
 878
 879         extent_io_tree_init(&fs_info->extent_cache);
 880         extent_io_tree_init(&fs_info->free_space_cache);
 881         extent_io_tree_init(&fs_info->block_group_cache);
 882         extent_io_tree_init(&fs_info->pinned_extents);
 883         extent_io_tree_init(&fs_info->pending_del);
 884         extent_io_tree_init(&fs_info->extent_ins);
 885         fs_info->excluded_extents = NULL;
 886
 887         fs_info->fs_root_tree = RB_ROOT;
 888         cache_tree_init(&fs_info->mapping_tree.cache_tree);
 889
 890         mutex_init(&fs_info->fs_mutex);
 891         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
 892         INIT_LIST_HEAD(&fs_info->space_info);
 893         INIT_LIST_HEAD(&fs_info->recow_ebs);
 894
 895         if (!writable)
 896                 fs_info->readonly = 1;
 897
 898         fs_info->super_bytenr = sb_bytenr;
 899         fs_info->data_alloc_profile = (u64)-1;
 900         fs_info->metadata_alloc_profile = (u64)-1;
 901         fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
 902         return fs_info;
 903 free_all:
 904         btrfs_free_fs_info(fs_info);
 905         return NULL;
 906 }
 907
 908 int btrfs_check_fs_compatibility(struct btrfs_super_block *sb, int writable)
 909 {
 910         u64 features;
 911
 912         features = btrfs_super_incompat_flags(sb) &
 913                    ~BTRFS_FEATURE_INCOMPAT_SUPP;
 914         if (features) {
 915                 printk("couldn't open because of unsupported "
 916                        "option features (%Lx).\n",
 917                        (unsigned long long)features);
 918                 return -ENOTSUP;
 919         }
 920
 921         features = btrfs_super_incompat_flags(sb);
 922         if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
 923                 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
 924                 btrfs_set_super_incompat_flags(sb, features);
 925         }
 926
 927         features = btrfs_super_compat_ro_flags(sb) &
 928                 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
 929         if (writable && features) {
 930                 printk("couldn't open RDWR because of unsupported "
 931                        "option features (%Lx).\n",
 932                        (unsigned long long)features);
 933                 return -ENOTSUP;
 934         }
 935         return 0;
 936 }
 937
 938 static int find_best_backup_root(struct btrfs_super_block *super)
 939 {
 940         struct btrfs_root_backup *backup;
 941         u64 orig_gen = btrfs_super_generation(super);
 942         u64 gen = 0;
 943         int best_index = 0;
 944         int i;
 945
 946         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
 947                 backup = super->super_roots + i;
 948                 if (btrfs_backup_tree_root_gen(backup) != orig_gen &&
 949                     btrfs_backup_tree_root_gen(backup) > gen) {
 950                         best_index = i;
 951                         gen = btrfs_backup_tree_root_gen(backup);
 952                 }
 953         }
 954         return best_index;
 955 }
 956
 957 static int setup_root_or_create_block(struct btrfs_fs_info *fs_info,
 958                                       unsigned flags,
 959                                       struct btrfs_root *info_root,
 960                                       u64 objectid, char *str)
 961 {
 962         struct btrfs_super_block *sb = fs_info->super_copy;
 963         struct btrfs_root *root = fs_info->tree_root;
 964         u32 nodesize = btrfs_super_nodesize(sb);
 965         int ret;
 966
 967         ret = find_and_setup_root(root, fs_info, objectid, info_root);
 968         if (ret) {
 969                 printk("Couldn't setup %s tree\n", str);
 970                 if (!(flags & OPEN_CTREE_PARTIAL))
 971                         return -EIO;
 972                 /*
 973                  * Need a blank node here just so we don't screw up in the
 974                  * million of places that assume a root has a valid ->node
 975                  */
 976                 info_root->node =
 977                         btrfs_find_create_tree_block(fs_info, 0, nodesize);
 978                 if (!info_root->node)
 979                         return -ENOMEM;
 980                 clear_extent_buffer_uptodate(info_root->node);
 981         }
 982
 983         return 0;
 984 }
 985
 986 int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
 987                           unsigned flags)
 988 {
 989         struct btrfs_super_block *sb = fs_info->super_copy;
 990         struct btrfs_root *root;
 991         struct btrfs_key key;
 992         u32 sectorsize;
 993         u32 nodesize;
 994         u32 leafsize;
 995         u32 stripesize;
 996         u64 generation;
 997         u32 blocksize;
 998         int ret;
 999
1000         nodesize = btrfs_super_nodesize(sb);
1001         leafsize = btrfs_super_leafsize(sb);
1002         sectorsize = btrfs_super_sectorsize(sb);
1003         stripesize = btrfs_super_stripesize(sb);
1004
1005         root = fs_info->tree_root;
1006         __setup_root(nodesize, leafsize, sectorsize, stripesize,
1007                      root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
1008         blocksize = root->nodesize;
1009         generation = btrfs_super_generation(sb);
1010
1011         if (!root_tree_bytenr && !(flags & OPEN_CTREE_BACKUP_ROOT)) {
1012                 root_tree_bytenr = btrfs_super_root(sb);
1013         } else if (flags & OPEN_CTREE_BACKUP_ROOT) {
1014                 struct btrfs_root_backup *backup;
1015                 int index = find_best_backup_root(sb);
1016                 if (index >= BTRFS_NUM_BACKUP_ROOTS) {
1017                         fprintf(stderr, "Invalid backup root number\n");
1018                         return -EIO;
1019                 }
1020                 backup = fs_info->super_copy->super_roots + index;
1021                 root_tree_bytenr = btrfs_backup_tree_root(backup);
1022                 generation = btrfs_backup_tree_root_gen(backup);
1023         }
1024
1025         root->node = read_tree_block(root, root_tree_bytenr, blocksize,
1026                                      generation);
1027         if (!extent_buffer_uptodate(root->node)) {
1028                 fprintf(stderr, "Couldn't read tree root\n");
1029                 return -EIO;
1030         }
1031
1032         ret = setup_root_or_create_block(fs_info, flags, fs_info->extent_root,
1033                                          BTRFS_EXTENT_TREE_OBJECTID, "extent");
1034         if (ret)
1035                 return ret;
1036         fs_info->extent_root->track_dirty = 1;
1037
1038         ret = find_and_setup_root(root, fs_info, BTRFS_DEV_TREE_OBJECTID,
1039                                   fs_info->dev_root);
1040         if (ret) {
1041                 printk("Couldn't setup device tree\n");
1042                 return -EIO;
1043         }
1044         fs_info->dev_root->track_dirty = 1;
1045
1046         ret = setup_root_or_create_block(fs_info, flags, fs_info->csum_root,
1047                                          BTRFS_CSUM_TREE_OBJECTID, "csum");
1048         if (ret)
1049                 return ret;
1050         fs_info->csum_root->track_dirty = 1;
1051
1052         ret = find_and_setup_root(root, fs_info, BTRFS_QUOTA_TREE_OBJECTID,
1053                                   fs_info->quota_root);
1054         if (ret == 0)
1055                 fs_info->quota_enabled = 1;
1056
1057         if (btrfs_fs_compat_ro(fs_info, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
1058                 ret = find_and_setup_root(root, fs_info, BTRFS_FREE_SPACE_TREE_OBJECTID,
1059                                           fs_info->free_space_root);
1060                 if (ret) {
1061                         printk("Couldn't read free space tree\n");
1062                         return -EIO;
1063                 }
1064                 fs_info->free_space_root->track_dirty = 1;
1065         }
1066
1067         ret = find_and_setup_log_root(root, fs_info, sb);
1068         if (ret) {
1069                 printk("Couldn't setup log root tree\n");
1070                 if (!(flags & OPEN_CTREE_PARTIAL))
1071                         return -EIO;
1072         }
1073
1074         fs_info->generation = generation;
1075         fs_info->last_trans_committed = generation;
1076         if (extent_buffer_uptodate(fs_info->extent_root->node) &&
1077             !(flags & OPEN_CTREE_NO_BLOCK_GROUPS))
1078                 btrfs_read_block_groups(fs_info->tree_root);
1079
1080         key.objectid = BTRFS_FS_TREE_OBJECTID;
1081         key.type = BTRFS_ROOT_ITEM_KEY;
1082         key.offset = (u64)-1;
1083         fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
1084
1085         if (IS_ERR(fs_info->fs_root))
1086                 return -EIO;
1087         return 0;
1088 }
1089
1090 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info)
1091 {
1092         if (fs_info->free_space_root)
1093                 free_extent_buffer(fs_info->free_space_root->node);
1094         if (fs_info->quota_root)
1095                 free_extent_buffer(fs_info->quota_root->node);
1096         if (fs_info->csum_root)
1097                 free_extent_buffer(fs_info->csum_root->node);
1098         if (fs_info->dev_root)
1099                 free_extent_buffer(fs_info->dev_root->node);
1100         if (fs_info->extent_root)
1101                 free_extent_buffer(fs_info->extent_root->node);
1102         if (fs_info->tree_root)
1103                 free_extent_buffer(fs_info->tree_root->node);
1104         if (fs_info->log_root_tree)
1105                 free_extent_buffer(fs_info->log_root_tree->node);
1106         if (fs_info->chunk_root)
1107                 free_extent_buffer(fs_info->chunk_root->node);
1108 }
1109
1110 static void free_map_lookup(struct cache_extent *ce)
1111 {
1112         struct map_lookup *map;
1113
1114         map = container_of(ce, struct map_lookup, ce);
1115         kfree(map);
1116 }
1117
1118 FREE_EXTENT_CACHE_BASED_TREE(mapping_cache, free_map_lookup);
1119
1120 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info)
1121 {
1122         while (!list_empty(&fs_info->recow_ebs)) {
1123                 struct extent_buffer *eb;
1124                 eb = list_first_entry(&fs_info->recow_ebs,
1125                                       struct extent_buffer, recow);
1126                 list_del_init(&eb->recow);
1127                 free_extent_buffer(eb);
1128         }
1129         free_mapping_cache_tree(&fs_info->mapping_tree.cache_tree);
1130         extent_io_tree_cleanup(&fs_info->extent_cache);
1131         extent_io_tree_cleanup(&fs_info->free_space_cache);
1132         extent_io_tree_cleanup(&fs_info->block_group_cache);
1133         extent_io_tree_cleanup(&fs_info->pinned_extents);
1134         extent_io_tree_cleanup(&fs_info->pending_del);
1135         extent_io_tree_cleanup(&fs_info->extent_ins);
1136 }
1137
1138 int btrfs_scan_fs_devices(int fd, const char *path,
1139                           struct btrfs_fs_devices **fs_devices,
1140                           u64 sb_bytenr, unsigned sbflags,
1141                           int skip_devices)
1142 {
1143         u64 total_devs;
1144         u64 dev_size;
1145         off_t seek_ret;
1146         int ret;
1147         if (!sb_bytenr)
1148                 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1149
1150         seek_ret = lseek(fd, 0, SEEK_END);
1151         if (seek_ret < 0)
1152                 return -errno;
1153
1154         dev_size = seek_ret;
1155         lseek(fd, 0, SEEK_SET);
1156         if (sb_bytenr > dev_size) {
1157                 error("superblock bytenr %llu is larger than device size %llu",
1158                                 (unsigned long long)sb_bytenr,
1159                                 (unsigned long long)dev_size);
1160                 return -EINVAL;
1161         }
1162
1163         ret = btrfs_scan_one_device(fd, path, fs_devices,
1164                                     &total_devs, sb_bytenr, sbflags);
1165         if (ret) {
1166                 fprintf(stderr, "No valid Btrfs found on %s\n", path);
1167                 return ret;
1168         }
1169
1170         if (!skip_devices && total_devs != 1) {
1171                 ret = btrfs_scan_lblkid();
1172                 if (ret)
1173                         return ret;
1174         }
1175         return 0;
1176 }
1177
1178 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info,
1179                                           u64 chunk_root_bytenr)
1180 {
1181         struct btrfs_super_block *sb = fs_info->super_copy;
1182         u32 sectorsize;
1183         u32 nodesize;
1184         u32 leafsize;
1185         u32 blocksize;
1186         u32 stripesize;
1187         u64 generation;
1188         int ret;
1189
1190         nodesize = btrfs_super_nodesize(sb);
1191         leafsize = btrfs_super_leafsize(sb);
1192         sectorsize = btrfs_super_sectorsize(sb);
1193         stripesize = btrfs_super_stripesize(sb);
1194
1195         __setup_root(nodesize, leafsize, sectorsize, stripesize,
1196                      fs_info->chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
1197
1198         ret = btrfs_read_sys_array(fs_info->chunk_root);
1199         if (ret)
1200                 return ret;
1201
1202         blocksize = fs_info->chunk_root->nodesize;
1203         generation = btrfs_super_chunk_root_generation(sb);
1204
1205         if (chunk_root_bytenr && !IS_ALIGNED(chunk_root_bytenr,
1206                                             btrfs_super_sectorsize(sb))) {
1207                 warning("chunk_root_bytenr %llu is unaligned to %u, ignore it",
1208                         chunk_root_bytenr, btrfs_super_sectorsize(sb));
1209                 chunk_root_bytenr = 0;
1210         }
1211
1212         if (!chunk_root_bytenr)
1213                 chunk_root_bytenr = btrfs_super_chunk_root(sb);
1214         else
1215                 generation = 0;
1216
1217         fs_info->chunk_root->node = read_tree_block(fs_info->chunk_root,
1218                                                     chunk_root_bytenr,
1219                                                     blocksize, generation);
1220         if (!extent_buffer_uptodate(fs_info->chunk_root->node)) {
1221                 if (fs_info->ignore_chunk_tree_error) {
1222                         warning("cannot read chunk root, continue anyway");
1223                         fs_info->chunk_root = NULL;
1224                         return 0;
1225                 } else {
1226                         error("cannot read chunk root");
1227                         return -EIO;
1228                 }
1229         }
1230
1231         if (!(btrfs_super_flags(sb) & BTRFS_SUPER_FLAG_METADUMP)) {
1232                 ret = btrfs_read_chunk_tree(fs_info->chunk_root);
1233                 if (ret) {
1234                         fprintf(stderr, "Couldn't read chunk tree\n");
1235                         return ret;
1236                 }
1237         }
1238         return 0;
1239 }
1240
1241 static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
1242                                              u64 sb_bytenr,
1243                                              u64 root_tree_bytenr,
1244                                              u64 chunk_root_bytenr,
1245                                              unsigned flags)
1246 {
1247         struct btrfs_fs_info *fs_info;
1248         struct btrfs_super_block *disk_super;
1249         struct btrfs_fs_devices *fs_devices = NULL;
1250         struct extent_buffer *eb;
1251         int ret;
1252         int oflags;
1253         unsigned sbflags = SBREAD_DEFAULT;
1254
1255         if (sb_bytenr == 0)
1256                 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1257
1258         /* try to drop all the caches */
1259         if (posix_fadvise(fp, 0, 0, POSIX_FADV_DONTNEED))
1260                 fprintf(stderr, "Warning, could not drop caches\n");
1261
1262         fs_info = btrfs_new_fs_info(flags & OPEN_CTREE_WRITES, sb_bytenr);
1263         if (!fs_info) {
1264                 fprintf(stderr, "Failed to allocate memory for fs_info\n");
1265                 return NULL;
1266         }
1267         if (flags & OPEN_CTREE_RESTORE)
1268                 fs_info->on_restoring = 1;
1269         if (flags & OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS)
1270                 fs_info->suppress_check_block_errors = 1;
1271         if (flags & OPEN_CTREE_IGNORE_FSID_MISMATCH)
1272                 fs_info->ignore_fsid_mismatch = 1;
1273         if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR)
1274                 fs_info->ignore_chunk_tree_error = 1;
1275
1276         if ((flags & OPEN_CTREE_RECOVER_SUPER)
1277              && (flags & OPEN_CTREE_FS_PARTIAL)) {
1278                 fprintf(stderr,
1279                     "cannot open a partially created filesystem for recovery");
1280                 goto out;
1281         }
1282
1283         if (flags & OPEN_CTREE_FS_PARTIAL)
1284                 sbflags = SBREAD_PARTIAL;
1285
1286         ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr, sbflags,
1287                         (flags & OPEN_CTREE_NO_DEVICES));
1288         if (ret)
1289                 goto out;
1290
1291         fs_info->fs_devices = fs_devices;
1292         if (flags & OPEN_CTREE_WRITES)
1293                 oflags = O_RDWR;
1294         else
1295                 oflags = O_RDONLY;
1296
1297         if (flags & OPEN_CTREE_EXCLUSIVE)
1298                 oflags |= O_EXCL;
1299
1300         ret = btrfs_open_devices(fs_devices, oflags);
1301         if (ret)
1302                 goto out;
1303
1304         disk_super = fs_info->super_copy;
1305         if (flags & OPEN_CTREE_RECOVER_SUPER)
1306                 ret = btrfs_read_dev_super(fs_devices->latest_bdev, disk_super,
1307                                 sb_bytenr, SBREAD_RECOVER);
1308         else
1309                 ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr,
1310                                 sbflags);
1311         if (ret) {
1312                 printk("No valid btrfs found\n");
1313                 goto out_devices;
1314         }
1315
1316         if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID &&
1317             !fs_info->ignore_fsid_mismatch) {
1318                 fprintf(stderr, "ERROR: Filesystem UUID change in progress\n");
1319                 goto out_devices;
1320         }
1321
1322         memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
1323
1324         ret = btrfs_check_fs_compatibility(fs_info->super_copy,
1325                                            flags & OPEN_CTREE_WRITES);
1326         if (ret)
1327                 goto out_devices;
1328
1329         ret = btrfs_setup_chunk_tree_and_device_map(fs_info, chunk_root_bytenr);
1330         if (ret)
1331                 goto out_chunk;
1332
1333         /* Chunk tree root is unable to read, return directly */
1334         if (!fs_info->chunk_root)
1335                 return fs_info;
1336
1337         eb = fs_info->chunk_root->node;
1338         read_extent_buffer(eb, fs_info->chunk_tree_uuid,
1339                            btrfs_header_chunk_tree_uuid(eb),
1340                            BTRFS_UUID_SIZE);
1341
1342         ret = btrfs_setup_all_roots(fs_info, root_tree_bytenr, flags);
1343         if (ret && !(flags & __OPEN_CTREE_RETURN_CHUNK_ROOT) &&
1344             !fs_info->ignore_chunk_tree_error)
1345                 goto out_chunk;
1346
1347         return fs_info;
1348
1349 out_chunk:
1350         btrfs_release_all_roots(fs_info);
1351         btrfs_cleanup_all_caches(fs_info);
1352 out_devices:
1353         btrfs_close_devices(fs_devices);
1354 out:
1355         btrfs_free_fs_info(fs_info);
1356         return NULL;
1357 }
1358
1359 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
1360                                          u64 sb_bytenr, u64 root_tree_bytenr,
1361                                          u64 chunk_root_bytenr,
1362                                          unsigned flags)
1363 {
1364         int fp;
1365         int ret;
1366         struct btrfs_fs_info *info;
1367         int oflags = O_RDWR;
1368         struct stat st;
1369
1370         ret = stat(filename, &st);
1371         if (ret < 0) {
1372                 error("cannot stat '%s': %s", filename, strerror(errno));
1373                 return NULL;
1374         }
1375         if (!(((st.st_mode & S_IFMT) == S_IFREG) || ((st.st_mode & S_IFMT) == S_IFBLK))) {
1376                 error("not a regular file or block device: %s", filename);
1377                 return NULL;
1378         }
1379
1380         if (!(flags & OPEN_CTREE_WRITES))
1381                 oflags = O_RDONLY;
1382
1383         fp = open(filename, oflags);
1384         if (fp < 0) {
1385                 error("cannot open '%s': %s", filename, strerror(errno));
1386                 return NULL;
1387         }
1388         info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
1389                                chunk_root_bytenr, flags);
1390         close(fp);
1391         return info;
1392 }
1393
1394 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
1395                               unsigned flags)
1396 {
1397         struct btrfs_fs_info *info;
1398
1399         /* This flags may not return fs_info with any valid root */
1400         BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
1401         info = open_ctree_fs_info(filename, sb_bytenr, 0, 0, flags);
1402         if (!info)
1403                 return NULL;
1404         if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1405                 return info->chunk_root;
1406         return info->fs_root;
1407 }
1408
1409 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
1410                                  unsigned flags)
1411 {
1412         struct btrfs_fs_info *info;
1413
1414         /* This flags may not return fs_info with any valid root */
1415         if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR) {
1416                 error("invalid open_ctree flags: 0x%llx",
1417                                 (unsigned long long)flags);
1418                 return NULL;
1419         }
1420         info = __open_ctree_fd(fp, path, sb_bytenr, 0, 0, flags);
1421         if (!info)
1422                 return NULL;
1423         if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1424                 return info->chunk_root;
1425         return info->fs_root;
1426 }
1427
1428 /*
1429  * Check if the super is valid:
1430  * - nodesize/sectorsize - minimum, maximum, alignment
1431  * - tree block starts   - alignment
1432  * - number of devices   - something sane
1433  * - sys array size      - maximum
1434  */
1435 static int check_super(struct btrfs_super_block *sb, unsigned sbflags)
1436 {
1437         u8 result[BTRFS_CSUM_SIZE];
1438         u32 crc;
1439         u16 csum_type;
1440         int csum_size;
1441
1442         if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
1443                 if (btrfs_super_magic(sb) == BTRFS_MAGIC_PARTIAL) {
1444                         if (!(sbflags & SBREAD_PARTIAL)) {
1445                                 error("superblock magic doesn't match");
1446                                 return -EIO;
1447                         }
1448                 }
1449         }
1450
1451         csum_type = btrfs_super_csum_type(sb);
1452         if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
1453                 error("unsupported checksum algorithm %u", csum_type);
1454                 return -EIO;
1455         }
1456         csum_size = btrfs_csum_sizes[csum_type];
1457
1458         crc = ~(u32)0;
1459         crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1460                               BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1461         btrfs_csum_final(crc, result);
1462
1463         if (memcmp(result, sb->csum, csum_size)) {
1464                 error("superblock checksum mismatch");
1465                 return -EIO;
1466         }
1467         if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
1468                 error("tree_root level too big: %d >= %d",
1469                         btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
1470                 goto error_out;
1471         }
1472         if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
1473                 error("chunk_root level too big: %d >= %d",
1474                         btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
1475                 goto error_out;
1476         }
1477         if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
1478                 error("log_root level too big: %d >= %d",
1479                         btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
1480                 goto error_out;
1481         }
1482
1483         if (!IS_ALIGNED(btrfs_super_root(sb), 4096)) {
1484                 error("tree_root block unaligned: %llu", btrfs_super_root(sb));
1485                 goto error_out;
1486         }
1487         if (!IS_ALIGNED(btrfs_super_chunk_root(sb), 4096)) {
1488                 error("chunk_root block unaligned: %llu",
1489                         btrfs_super_chunk_root(sb));
1490                 goto error_out;
1491         }
1492         if (!IS_ALIGNED(btrfs_super_log_root(sb), 4096)) {
1493                 error("log_root block unaligned: %llu",
1494                         btrfs_super_log_root(sb));
1495                 goto error_out;
1496         }
1497         if (btrfs_super_nodesize(sb) < 4096) {
1498                 error("nodesize too small: %u < 4096",
1499                         btrfs_super_nodesize(sb));
1500                 goto error_out;
1501         }
1502         if (!IS_ALIGNED(btrfs_super_nodesize(sb), 4096)) {
1503                 error("nodesize unaligned: %u", btrfs_super_nodesize(sb));
1504                 goto error_out;
1505         }
1506         if (btrfs_super_sectorsize(sb) < 4096) {
1507                 error("sectorsize too small: %u < 4096",
1508                         btrfs_super_sectorsize(sb));
1509                 goto error_out;
1510         }
1511         if (!IS_ALIGNED(btrfs_super_sectorsize(sb), 4096)) {
1512                 error("sectorsize unaligned: %u", btrfs_super_sectorsize(sb));
1513                 goto error_out;
1514         }
1515         if (btrfs_super_total_bytes(sb) == 0) {
1516                 error("invalid total_bytes 0");
1517                 goto error_out;
1518         }
1519         if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
1520                 error("invalid bytes_used %llu", btrfs_super_bytes_used(sb));
1521                 goto error_out;
1522         }
1523         if ((btrfs_super_stripesize(sb) != 4096)
1524                 && (btrfs_super_stripesize(sb) != btrfs_super_sectorsize(sb))) {
1525                 error("invalid stripesize %u", btrfs_super_stripesize(sb));
1526                 goto error_out;
1527         }
1528
1529         if (memcmp(sb->fsid, sb->dev_item.fsid, BTRFS_UUID_SIZE) != 0) {
1530                 char fsid[BTRFS_UUID_UNPARSED_SIZE];
1531                 char dev_fsid[BTRFS_UUID_UNPARSED_SIZE];
1532
1533                 uuid_unparse(sb->fsid, fsid);
1534                 uuid_unparse(sb->dev_item.fsid, dev_fsid);
1535                 error("dev_item UUID does not match fsid: %s != %s",
1536                         dev_fsid, fsid);
1537                 goto error_out;
1538         }
1539
1540         /*
1541          * Hint to catch really bogus numbers, bitflips or so
1542          */
1543         if (btrfs_super_num_devices(sb) > (1UL << 31)) {
1544                 warning("suspicious number of devices: %llu",
1545                         btrfs_super_num_devices(sb));
1546         }
1547
1548         if (btrfs_super_num_devices(sb) == 0) {
1549                 error("number of devices is 0");
1550                 goto error_out;
1551         }
1552
1553         /*
1554          * Obvious sys_chunk_array corruptions, it must hold at least one key
1555          * and one chunk
1556          */
1557         if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
1558                 error("system chunk array too big %u > %u",
1559                       btrfs_super_sys_array_size(sb),
1560                       BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
1561                 goto error_out;
1562         }
1563         if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
1564                         + sizeof(struct btrfs_chunk)) {
1565                 error("system chunk array too small %u < %lu",
1566                       btrfs_super_sys_array_size(sb),
1567                       sizeof(struct btrfs_disk_key) +
1568                       sizeof(struct btrfs_chunk));
1569                 goto error_out;
1570         }
1571
1572         return 0;
1573
1574 error_out:
1575         error("superblock checksum matches but it has invalid members");
1576         return -EIO;
1577 }
1578
1579 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
1580                          unsigned sbflags)
1581 {
1582         u8 fsid[BTRFS_FSID_SIZE];
1583         int fsid_is_initialized = 0;
1584         char tmp[BTRFS_SUPER_INFO_SIZE];
1585         struct btrfs_super_block *buf = (struct btrfs_super_block *)tmp;
1586         int i;
1587         int ret;
1588         int max_super = sbflags & SBREAD_RECOVER ? BTRFS_SUPER_MIRROR_MAX : 1;
1589         u64 transid = 0;
1590         u64 bytenr;
1591
1592         if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1593                 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
1594                 /* real error */
1595                 if (ret < 0)
1596                         return -errno;
1597
1598                 /* Not large enough sb, return -ENOENT instead of normal -EIO */
1599                 if (ret < BTRFS_SUPER_INFO_SIZE)
1600                         return -ENOENT;
1601
1602                 if (btrfs_super_bytenr(buf) != sb_bytenr)
1603                         return -EIO;
1604
1605                 ret = check_super(buf, sbflags);
1606                 if (ret < 0)
1607                         return ret;
1608                 memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1609                 return 0;
1610         }
1611
1612         /*
1613         * we would like to check all the supers, but that would make
1614         * a btrfs mount succeed after a mkfs from a different FS.
1615         * So, we need to add a special mount option to scan for
1616         * later supers, using BTRFS_SUPER_MIRROR_MAX instead
1617         */
1618
1619         for (i = 0; i < max_super; i++) {
1620                 bytenr = btrfs_sb_offset(i);
1621                 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, bytenr);
1622                 if (ret < BTRFS_SUPER_INFO_SIZE)
1623                         break;
1624
1625                 if (btrfs_super_bytenr(buf) != bytenr )
1626                         continue;
1627                 /* if magic is NULL, the device was removed */
1628                 if (btrfs_super_magic(buf) == 0 && i == 0)
1629                         break;
1630                 if (check_super(buf, sbflags))
1631                         continue;
1632
1633                 if (!fsid_is_initialized) {
1634                         memcpy(fsid, buf->fsid, sizeof(fsid));
1635                         fsid_is_initialized = 1;
1636                 } else if (memcmp(fsid, buf->fsid, sizeof(fsid))) {
1637                         /*
1638                          * the superblocks (the original one and
1639                          * its backups) contain data of different
1640                          * filesystems -> the super cannot be trusted
1641                          */
1642                         continue;
1643                 }
1644
1645                 if (btrfs_super_generation(buf) > transid) {
1646                         memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1647                         transid = btrfs_super_generation(buf);
1648                 }
1649         }
1650
1651         return transid > 0 ? 0 : -1;
1652 }
1653
1654 static int write_dev_supers(struct btrfs_root *root,
1655                             struct btrfs_super_block *sb,
1656                             struct btrfs_device *device)
1657 {
1658         u64 bytenr;
1659         u32 crc;
1660         int i, ret;
1661
1662         if (root->fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1663                 btrfs_set_super_bytenr(sb, root->fs_info->super_bytenr);
1664                 crc = ~(u32)0;
1665                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1666                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1667                 btrfs_csum_final(crc, &sb->csum[0]);
1668
1669                 /*
1670                  * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1671                  * zero filled, we can use it directly
1672                  */
1673                 ret = pwrite64(device->fd, root->fs_info->super_copy,
1674                                 BTRFS_SUPER_INFO_SIZE,
1675                                 root->fs_info->super_bytenr);
1676                 if (ret != BTRFS_SUPER_INFO_SIZE)
1677                         goto write_err;
1678                 return 0;
1679         }
1680
1681         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1682                 bytenr = btrfs_sb_offset(i);
1683                 if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
1684                         break;
1685
1686                 btrfs_set_super_bytenr(sb, bytenr);
1687
1688                 crc = ~(u32)0;
1689                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1690                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1691                 btrfs_csum_final(crc, &sb->csum[0]);
1692
1693                 /*
1694                  * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1695                  * zero filled, we can use it directly
1696                  */
1697                 ret = pwrite64(device->fd, root->fs_info->super_copy,
1698                                 BTRFS_SUPER_INFO_SIZE, bytenr);
1699                 if (ret != BTRFS_SUPER_INFO_SIZE)
1700                         goto write_err;
1701         }
1702
1703         return 0;
1704
1705 write_err:
1706         if (ret > 0)
1707                 fprintf(stderr, "WARNING: failed to write all sb data\n");
1708         else
1709                 fprintf(stderr, "WARNING: failed to write sb: %s\n",
1710                         strerror(errno));
1711         return ret;
1712 }
1713
1714 int write_all_supers(struct btrfs_root *root)
1715 {
1716         struct list_head *cur;
1717         struct list_head *head = &root->fs_info->fs_devices->devices;
1718         struct btrfs_device *dev;
1719         struct btrfs_super_block *sb;
1720         struct btrfs_dev_item *dev_item;
1721         int ret;
1722         u64 flags;
1723
1724         sb = root->fs_info->super_copy;
1725         dev_item = &sb->dev_item;
1726         list_for_each(cur, head) {
1727                 dev = list_entry(cur, struct btrfs_device, dev_list);
1728                 if (!dev->writeable)
1729                         continue;
1730
1731                 btrfs_set_stack_device_generation(dev_item, 0);
1732                 btrfs_set_stack_device_type(dev_item, dev->type);
1733                 btrfs_set_stack_device_id(dev_item, dev->devid);
1734                 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1735                 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1736                 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1737                 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1738                 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1739                 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1740                 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
1741
1742                 flags = btrfs_super_flags(sb);
1743                 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
1744
1745                 ret = write_dev_supers(root, sb, dev);
1746                 BUG_ON(ret);
1747         }
1748         return 0;
1749 }
1750
1751 int write_ctree_super(struct btrfs_trans_handle *trans,
1752                       struct btrfs_root *root)
1753 {
1754         int ret;
1755         struct btrfs_root *tree_root = root->fs_info->tree_root;
1756         struct btrfs_root *chunk_root = root->fs_info->chunk_root;
1757
1758         if (root->fs_info->readonly)
1759                 return 0;
1760
1761         btrfs_set_super_generation(root->fs_info->super_copy,
1762                                    trans->transid);
1763         btrfs_set_super_root(root->fs_info->super_copy,
1764                              tree_root->node->start);
1765         btrfs_set_super_root_level(root->fs_info->super_copy,
1766                                    btrfs_header_level(tree_root->node));
1767         btrfs_set_super_chunk_root(root->fs_info->super_copy,
1768                                    chunk_root->node->start);
1769         btrfs_set_super_chunk_root_level(root->fs_info->super_copy,
1770                                          btrfs_header_level(chunk_root->node));
1771         btrfs_set_super_chunk_root_generation(root->fs_info->super_copy,
1772                                 btrfs_header_generation(chunk_root->node));
1773
1774         ret = write_all_supers(root);
1775         if (ret)
1776                 fprintf(stderr, "failed to write new super block err %d\n", ret);
1777         return ret;
1778 }
1779
1780 int close_ctree_fs_info(struct btrfs_fs_info *fs_info)
1781 {
1782         int ret;
1783         struct btrfs_trans_handle *trans;
1784         struct btrfs_root *root = fs_info->tree_root;
1785
1786         if (fs_info->last_trans_committed !=
1787             fs_info->generation) {
1788                 BUG_ON(!root);
1789                 trans = btrfs_start_transaction(root, 1);
1790                 btrfs_commit_transaction(trans, root);
1791                 trans = btrfs_start_transaction(root, 1);
1792                 ret = commit_tree_roots(trans, fs_info);
1793                 BUG_ON(ret);
1794                 ret = __commit_transaction(trans, root);
1795                 BUG_ON(ret);
1796                 write_ctree_super(trans, root);
1797                 btrfs_free_transaction(root, trans);
1798         }
1799
1800         if (fs_info->finalize_on_close) {
1801                 btrfs_set_super_magic(fs_info->super_copy, BTRFS_MAGIC);
1802                 root->fs_info->finalize_on_close = 0;
1803                 ret = write_all_supers(root);
1804                 if (ret)
1805                         fprintf(stderr,
1806                                 "failed to write new super block err %d\n", ret);
1807         }
1808         btrfs_free_block_groups(fs_info);
1809
1810         free_fs_roots_tree(&fs_info->fs_root_tree);
1811
1812         btrfs_release_all_roots(fs_info);
1813         btrfs_close_devices(fs_info->fs_devices);
1814         btrfs_cleanup_all_caches(fs_info);
1815         btrfs_free_fs_info(fs_info);
1816         return 0;
1817 }
1818
1819 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1820                      struct extent_buffer *eb)
1821 {
1822         return clear_extent_buffer_dirty(eb);
1823 }
1824
1825 int wait_on_tree_block_writeback(struct btrfs_root *root,
1826                                  struct extent_buffer *eb)
1827 {
1828         return 0;
1829 }
1830
1831 void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
1832 {
1833         set_extent_buffer_dirty(eb);
1834 }
1835
1836 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1837 {
1838         int ret;
1839
1840         ret = extent_buffer_uptodate(buf);
1841         if (!ret)
1842                 return ret;
1843
1844         ret = verify_parent_transid(buf->tree, buf, parent_transid, 1);
1845         return !ret;
1846 }
1847
1848 int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
1849 {
1850         return set_extent_buffer_uptodate(eb);
1851 }