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 #define _XOPEN_SOURCE 600
  20 #define __USE_XOPEN2K
  21 #define _GNU_SOURCE 1
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #include <fcntl.h>
  27 #include <unistd.h>
  28 #include "kerncompat.h"
  29 #include "radix-tree.h"
  30 #include "ctree.h"
  31 #include "disk-io.h"
  32 #include "volumes.h"
  33 #include "transaction.h"
  34 #include "crc32c.h"
  35 #include "utils.h"
  36 #include "print-tree.h"
  37
  38 static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
  39 {
  40
  41         struct btrfs_fs_devices *fs_devices;
  42         int ret = 1;
  43
  44         if (buf->start != btrfs_header_bytenr(buf)) {
  45                 printk("Check tree block failed, want=%Lu, have=%Lu\n",
  46                        buf->start, btrfs_header_bytenr(buf));
  47                 return ret;
  48         }
  49
  50         fs_devices = root->fs_info->fs_devices;
  51         while (fs_devices) {
  52                 if (!memcmp_extent_buffer(buf, fs_devices->fsid,
  53                                           btrfs_header_fsid(),
  54                                           BTRFS_FSID_SIZE)) {
  55                         ret = 0;
  56                         break;
  57                 }
  58                 fs_devices = fs_devices->seed;
  59         }
  60         return ret;
  61 }
  62
  63 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
  64 {
  65         return crc32c(seed, data, len);
  66 }
  67
  68 void btrfs_csum_final(u32 crc, char *result)
  69 {
  70         *(__le32 *)result = ~cpu_to_le32(crc);
  71 }
  72
  73 static int __csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
  74                                   int verify, int silent)
  75 {
  76         char *result;
  77         u32 len;
  78         u32 crc = ~(u32)0;
  79
  80         result = malloc(csum_size * sizeof(char));
  81         if (!result)
  82                 return 1;
  83
  84         len = buf->len - BTRFS_CSUM_SIZE;
  85         crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len);
  86         btrfs_csum_final(crc, result);
  87
  88         if (verify) {
  89                 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
  90                         if (!silent)
  91                                 printk("checksum verify failed on %llu found %08X wanted %08X\n",
  92                                        (unsigned long long)buf->start,
  93                                        *((u32 *)result),
  94                                        *((u32*)(char *)buf->data));
  95                         free(result);
  96                         return 1;
  97                 }
  98         } else {
  99                 write_extent_buffer(buf, result, 0, csum_size);
 100         }
 101         free(result);
 102         return 0;
 103 }
 104
 105 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size, int verify)
 106 {
 107         return __csum_tree_block_size(buf, csum_size, verify, 0);
 108 }
 109
 110 int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size)
 111 {
 112         return __csum_tree_block_size(buf, csum_size, 1, 1);
 113 }
 114
 115 int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 116                            int verify)
 117 {
 118         u16 csum_size =
 119                 btrfs_super_csum_size(root->fs_info->super_copy);
 120         return csum_tree_block_size(buf, csum_size, verify);
 121 }
 122
 123 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
 124                                             u64 bytenr, u32 blocksize)
 125 {
 126         return find_extent_buffer(&root->fs_info->extent_cache,
 127                                   bytenr, blocksize);
 128 }
 129
 130 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
 131                                                  u64 bytenr, u32 blocksize)
 132 {
 133         return alloc_extent_buffer(&root->fs_info->extent_cache, bytenr,
 134                                    blocksize);
 135 }
 136
 137 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
 138                          u64 parent_transid)
 139 {
 140         int ret;
 141         struct extent_buffer *eb;
 142         u64 length;
 143         struct btrfs_multi_bio *multi = NULL;
 144         struct btrfs_device *device;
 145
 146         eb = btrfs_find_tree_block(root, bytenr, blocksize);
 147         if (eb && btrfs_buffer_uptodate(eb, parent_transid)) {
 148                 free_extent_buffer(eb);
 149                 return 0;
 150         }
 151
 152         length = blocksize;
 153         ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
 154                               bytenr, &length, &multi, 0, NULL);
 155         BUG_ON(ret);
 156         device = multi->stripes[0].dev;
 157         device->total_ios++;
 158         blocksize = min(blocksize, (u32)(64 * 1024));
 159         readahead(device->fd, multi->stripes[0].physical, blocksize);
 160         kfree(multi);
 161         return 0;
 162 }
 163
 164 static int verify_parent_transid(struct extent_io_tree *io_tree,
 165                                  struct extent_buffer *eb, u64 parent_transid,
 166                                  int ignore)
 167 {
 168         int ret;
 169
 170         if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 171                 return 0;
 172
 173         if (extent_buffer_uptodate(eb) &&
 174             btrfs_header_generation(eb) == parent_transid) {
 175                 ret = 0;
 176                 goto out;
 177         }
 178         printk("parent transid verify failed on %llu wanted %llu found %llu\n",
 179                (unsigned long long)eb->start,
 180                (unsigned long long)parent_transid,
 181                (unsigned long long)btrfs_header_generation(eb));
 182         if (ignore) {
 183                 eb->flags |= EXTENT_BAD_TRANSID;
 184                 printk("Ignoring transid failure\n");
 185                 return 0;
 186         }
 187
 188         ret = 1;
 189 out:
 190         clear_extent_buffer_uptodate(io_tree, eb);
 191         return ret;
 192
 193 }
 194
 195
 196 int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror)
 197 {
 198         unsigned long offset = 0;
 199         struct btrfs_multi_bio *multi = NULL;
 200         struct btrfs_device *device;
 201         int ret = 0;
 202         u64 read_len;
 203         unsigned long bytes_left = eb->len;
 204
 205         while (bytes_left) {
 206                 read_len = bytes_left;
 207                 device = NULL;
 208
 209                 if (!info->on_restoring) {
 210                         ret = btrfs_map_block(&info->mapping_tree, READ,
 211                                               eb->start + offset, &read_len, &multi,
 212                                               mirror, NULL);
 213                         if (ret) {
 214                                 printk("Couldn't map the block %Lu\n", eb->start + offset);
 215                                 kfree(multi);
 216                                 return -EIO;
 217                         }
 218                         device = multi->stripes[0].dev;
 219
 220                         if (device->fd == 0) {
 221                                 kfree(multi);
 222                                 return -EIO;
 223                         }
 224
 225                         eb->fd = device->fd;
 226                         device->total_ios++;
 227                         eb->dev_bytenr = multi->stripes[0].physical;
 228                         kfree(multi);
 229                         multi = NULL;
 230                 } else {
 231                         /* special case for restore metadump */
 232                         list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
 233                                 if (device->devid == 1)
 234                                         break;
 235                         }
 236
 237                         eb->fd = device->fd;
 238                         eb->dev_bytenr = eb->start;
 239                         device->total_ios++;
 240                 }
 241
 242                 if (read_len > bytes_left)
 243                         read_len = bytes_left;
 244
 245                 ret = read_extent_from_disk(eb, offset, read_len);
 246                 if (ret)
 247                         return -EIO;
 248                 offset += read_len;
 249                 bytes_left -= read_len;
 250         }
 251         return 0;
 252 }
 253
 254 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 255                                      u32 blocksize, u64 parent_transid)
 256 {
 257         int ret;
 258         struct extent_buffer *eb;
 259         u64 best_transid = 0;
 260         int mirror_num = 0;
 261         int good_mirror = 0;
 262         int num_copies;
 263         int ignore = 0;
 264
 265         eb = btrfs_find_create_tree_block(root, bytenr, blocksize);
 266         if (!eb)
 267                 return NULL;
 268
 269         if (btrfs_buffer_uptodate(eb, parent_transid))
 270                 return eb;
 271
 272         while (1) {
 273                 ret = read_whole_eb(root->fs_info, eb, mirror_num);
 274                 if (ret == 0 && check_tree_block(root, eb) == 0 &&
 275                     csum_tree_block(root, eb, 1) == 0 &&
 276                     verify_parent_transid(eb->tree, eb, parent_transid, ignore)
 277                     == 0) {
 278                         if (eb->flags & EXTENT_BAD_TRANSID &&
 279                             list_empty(&eb->recow)) {
 280                                 list_add_tail(&eb->recow,
 281                                               &root->fs_info->recow_ebs);
 282                                 eb->refs++;
 283                         }
 284                         btrfs_set_buffer_uptodate(eb);
 285                         return eb;
 286                 }
 287                 if (ignore) {
 288                         if (check_tree_block(root, eb))
 289                                 printk("read block failed check_tree_block\n");
 290                         else
 291                                 printk("Csum didn't match\n");
 292                         break;
 293                 }
 294                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 295                                               eb->start, eb->len);
 296                 if (num_copies == 1) {
 297                         ignore = 1;
 298                         continue;
 299                 }
 300                 if (btrfs_header_generation(eb) > best_transid) {
 301                         best_transid = btrfs_header_generation(eb);
 302                         good_mirror = mirror_num;
 303                 }
 304                 mirror_num++;
 305                 if (mirror_num > num_copies) {
 306                         mirror_num = good_mirror;
 307                         ignore = 1;
 308                         continue;
 309                 }
 310         }
 311         free_extent_buffer(eb);
 312         return NULL;
 313 }
 314
 315 static int write_tree_block(struct btrfs_trans_handle *trans,
 316                             struct btrfs_root *root,
 317                             struct extent_buffer *eb)
 318 {
 319         int ret;
 320         int dev_nr;
 321         u64 length;
 322         u64 *raid_map = NULL;
 323         struct btrfs_multi_bio *multi = NULL;
 324
 325         if (check_tree_block(root, eb))
 326                 BUG();
 327
 328         if (!btrfs_buffer_uptodate(eb, trans->transid))
 329                 BUG();
 330
 331         btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
 332         csum_tree_block(root, eb, 0);
 333
 334         dev_nr = 0;
 335         length = eb->len;
 336         ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE,
 337                               eb->start, &length, &multi, 0, &raid_map);
 338
 339         if (raid_map) {
 340                 ret = write_raid56_with_parity(root->fs_info, eb, multi,
 341                                                length, raid_map);
 342                 BUG_ON(ret);
 343         } else while (dev_nr < multi->num_stripes) {
 344                 BUG_ON(ret);
 345                 eb->fd = multi->stripes[dev_nr].dev->fd;
 346                 eb->dev_bytenr = multi->stripes[dev_nr].physical;
 347                 multi->stripes[dev_nr].dev->total_ios++;
 348                 dev_nr++;
 349                 ret = write_extent_to_disk(eb);
 350                 BUG_ON(ret);
 351         }
 352         kfree(multi);
 353         return 0;
 354 }
 355
 356 int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 357                         u32 stripesize, struct btrfs_root *root,
 358                         struct btrfs_fs_info *fs_info, u64 objectid)
 359 {
 360         root->node = NULL;
 361         root->commit_root = NULL;
 362         root->sectorsize = sectorsize;
 363         root->nodesize = nodesize;
 364         root->leafsize = leafsize;
 365         root->stripesize = stripesize;
 366         root->ref_cows = 0;
 367         root->track_dirty = 0;
 368
 369         root->fs_info = fs_info;
 370         root->objectid = objectid;
 371         root->last_trans = 0;
 372         root->highest_inode = 0;
 373         root->last_inode_alloc = 0;
 374
 375         INIT_LIST_HEAD(&root->dirty_list);
 376         memset(&root->root_key, 0, sizeof(root->root_key));
 377         memset(&root->root_item, 0, sizeof(root->root_item));
 378         root->root_key.objectid = objectid;
 379         return 0;
 380 }
 381
 382 static int update_cowonly_root(struct btrfs_trans_handle *trans,
 383                                struct btrfs_root *root)
 384 {
 385         int ret;
 386         u64 old_root_bytenr;
 387         struct btrfs_root *tree_root = root->fs_info->tree_root;
 388
 389         btrfs_write_dirty_block_groups(trans, root);
 390         while(1) {
 391                 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
 392                 if (old_root_bytenr == root->node->start)
 393                         break;
 394                 btrfs_set_root_bytenr(&root->root_item,
 395                                        root->node->start);
 396                 btrfs_set_root_generation(&root->root_item,
 397                                           trans->transid);
 398                 root->root_item.level = btrfs_header_level(root->node);
 399                 ret = btrfs_update_root(trans, tree_root,
 400                                         &root->root_key,
 401                                         &root->root_item);
 402                 BUG_ON(ret);
 403                 btrfs_write_dirty_block_groups(trans, root);
 404         }
 405         return 0;
 406 }
 407
 408 static int commit_tree_roots(struct btrfs_trans_handle *trans,
 409                              struct btrfs_fs_info *fs_info)
 410 {
 411         struct btrfs_root *root;
 412         struct list_head *next;
 413         struct extent_buffer *eb;
 414         int ret;
 415
 416         if (fs_info->readonly)
 417                 return 0;
 418
 419         eb = fs_info->tree_root->node;
 420         extent_buffer_get(eb);
 421         ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
 422         free_extent_buffer(eb);
 423         if (ret)
 424                 return ret;
 425
 426         while(!list_empty(&fs_info->dirty_cowonly_roots)) {
 427                 next = fs_info->dirty_cowonly_roots.next;
 428                 list_del_init(next);
 429                 root = list_entry(next, struct btrfs_root, dirty_list);
 430                 update_cowonly_root(trans, root);
 431                 free_extent_buffer(root->commit_root);
 432                 root->commit_root = NULL;
 433         }
 434
 435         return 0;
 436 }
 437
 438 static int __commit_transaction(struct btrfs_trans_handle *trans,
 439                                 struct btrfs_root *root)
 440 {
 441         u64 start;
 442         u64 end;
 443         struct extent_buffer *eb;
 444         struct extent_io_tree *tree = &root->fs_info->extent_cache;
 445         int ret;
 446
 447         while(1) {
 448                 ret = find_first_extent_bit(tree, 0, &start, &end,
 449                                             EXTENT_DIRTY);
 450                 if (ret)
 451                         break;
 452                 while(start <= end) {
 453                         eb = find_first_extent_buffer(tree, start);
 454                         BUG_ON(!eb || eb->start != start);
 455                         ret = write_tree_block(trans, root, eb);
 456                         BUG_ON(ret);
 457                         start += eb->len;
 458                         clear_extent_buffer_dirty(eb);
 459                         free_extent_buffer(eb);
 460                 }
 461         }
 462         return 0;
 463 }
 464
 465 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 466                              struct btrfs_root *root)
 467 {
 468         u64 transid = trans->transid;
 469         int ret = 0;
 470         struct btrfs_fs_info *fs_info = root->fs_info;
 471
 472         if (root->commit_root == root->node)
 473                 goto commit_tree;
 474
 475         free_extent_buffer(root->commit_root);
 476         root->commit_root = NULL;
 477
 478         btrfs_set_root_bytenr(&root->root_item, root->node->start);
 479         btrfs_set_root_generation(&root->root_item, trans->transid);
 480         root->root_item.level = btrfs_header_level(root->node);
 481         ret = btrfs_update_root(trans, root->fs_info->tree_root,
 482                                 &root->root_key, &root->root_item);
 483         BUG_ON(ret);
 484 commit_tree:
 485         ret = commit_tree_roots(trans, fs_info);
 486         BUG_ON(ret);
 487         ret = __commit_transaction(trans, root);
 488         BUG_ON(ret);
 489         write_ctree_super(trans, root);
 490         btrfs_finish_extent_commit(trans, fs_info->extent_root,
 491                                    &fs_info->pinned_extents);
 492         btrfs_free_transaction(root, trans);
 493         free_extent_buffer(root->commit_root);
 494         root->commit_root = NULL;
 495         fs_info->running_transaction = NULL;
 496         fs_info->last_trans_committed = transid;
 497         return 0;
 498 }
 499
 500 static int find_and_setup_root(struct btrfs_root *tree_root,
 501                                struct btrfs_fs_info *fs_info,
 502                                u64 objectid, struct btrfs_root *root)
 503 {
 504         int ret;
 505         u32 blocksize;
 506         u64 generation;
 507
 508         __setup_root(tree_root->nodesize, tree_root->leafsize,
 509                      tree_root->sectorsize, tree_root->stripesize,
 510                      root, fs_info, objectid);
 511         ret = btrfs_find_last_root(tree_root, objectid,
 512                                    &root->root_item, &root->root_key);
 513         if (ret)
 514                 return ret;
 515
 516         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 517         generation = btrfs_root_generation(&root->root_item);
 518         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 519                                      blocksize, generation);
 520         if (!extent_buffer_uptodate(root->node))
 521                 return -EIO;
 522
 523         return 0;
 524 }
 525
 526 static int find_and_setup_log_root(struct btrfs_root *tree_root,
 527                                struct btrfs_fs_info *fs_info,
 528                                struct btrfs_super_block *disk_super)
 529 {
 530         u32 blocksize;
 531         u64 blocknr = btrfs_super_log_root(disk_super);
 532         struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
 533
 534         if (!log_root)
 535                 return -ENOMEM;
 536
 537         if (blocknr == 0) {
 538                 free(log_root);
 539                 return 0;
 540         }
 541
 542         blocksize = btrfs_level_size(tree_root,
 543                              btrfs_super_log_root_level(disk_super));
 544
 545         __setup_root(tree_root->nodesize, tree_root->leafsize,
 546                      tree_root->sectorsize, tree_root->stripesize,
 547                      log_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
 548
 549         log_root->node = read_tree_block(tree_root, blocknr,
 550                                      blocksize,
 551                                      btrfs_super_generation(disk_super) + 1);
 552
 553         fs_info->log_root_tree = log_root;
 554
 555         if (!extent_buffer_uptodate(log_root->node)) {
 556                 free_extent_buffer(log_root->node);
 557                 free(log_root);
 558                 fs_info->log_root_tree = NULL;
 559                 return -EIO;
 560         }
 561
 562         return 0;
 563 }
 564
 565
 566 int btrfs_free_fs_root(struct btrfs_root *root)
 567 {
 568         if (root->node)
 569                 free_extent_buffer(root->node);
 570         if (root->commit_root)
 571                 free_extent_buffer(root->commit_root);
 572         kfree(root);
 573         return 0;
 574 }
 575
 576 static void __free_fs_root(struct rb_node *node)
 577 {
 578         struct btrfs_root *root;
 579
 580         root = container_of(node, struct btrfs_root, rb_node);
 581         btrfs_free_fs_root(root);
 582 }
 583
 584 FREE_RB_BASED_TREE(fs_roots, __free_fs_root);
 585
 586 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
 587                                                struct btrfs_key *location)
 588 {
 589         struct btrfs_root *root;
 590         struct btrfs_root *tree_root = fs_info->tree_root;
 591         struct btrfs_path *path;
 592         struct extent_buffer *l;
 593         u64 generation;
 594         u32 blocksize;
 595         int ret = 0;
 596
 597         root = malloc(sizeof(*root));
 598         if (!root)
 599                 return ERR_PTR(-ENOMEM);
 600         memset(root, 0, sizeof(*root));
 601         if (location->offset == (u64)-1) {
 602                 ret = find_and_setup_root(tree_root, fs_info,
 603                                           location->objectid, root);
 604                 if (ret) {
 605                         free(root);
 606                         return ERR_PTR(ret);
 607                 }
 608                 goto insert;
 609         }
 610
 611         __setup_root(tree_root->nodesize, tree_root->leafsize,
 612                      tree_root->sectorsize, tree_root->stripesize,
 613                      root, fs_info, location->objectid);
 614
 615         path = btrfs_alloc_path();
 616         BUG_ON(!path);
 617         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
 618         if (ret != 0) {
 619                 if (ret > 0)
 620                         ret = -ENOENT;
 621                 goto out;
 622         }
 623         l = path->nodes[0];
 624         read_extent_buffer(l, &root->root_item,
 625                btrfs_item_ptr_offset(l, path->slots[0]),
 626                sizeof(root->root_item));
 627         memcpy(&root->root_key, location, sizeof(*location));
 628         ret = 0;
 629 out:
 630         btrfs_release_path(path);
 631         btrfs_free_path(path);
 632         if (ret) {
 633                 free(root);
 634                 return ERR_PTR(ret);
 635         }
 636         generation = btrfs_root_generation(&root->root_item);
 637         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 638         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 639                                      blocksize, generation);
 640         BUG_ON(!root->node);
 641 insert:
 642         root->ref_cows = 1;
 643         return root;
 644 }
 645
 646 static int btrfs_fs_roots_compare_objectids(struct rb_node *node,
 647                                             void *data)
 648 {
 649         u64 objectid = *((u64 *)data);
 650         struct btrfs_root *root;
 651
 652         root = rb_entry(node, struct btrfs_root, rb_node);
 653         if (objectid > root->objectid)
 654                 return 1;
 655         else if (objectid < root->objectid)
 656                 return -1;
 657         else
 658                 return 0;
 659 }
 660
 661 static int btrfs_fs_roots_compare_roots(struct rb_node *node1,
 662                                         struct rb_node *node2)
 663 {
 664         struct btrfs_root *root;
 665
 666         root = rb_entry(node2, struct btrfs_root, rb_node);
 667         return btrfs_fs_roots_compare_objectids(node1, (void *)&root->objectid);
 668 }
 669
 670 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 671                                       struct btrfs_key *location)
 672 {
 673         struct btrfs_root *root;
 674         struct rb_node *node;
 675         int ret;
 676
 677         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
 678                 return fs_info->tree_root;
 679         if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
 680                 return fs_info->extent_root;
 681         if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
 682                 return fs_info->chunk_root;
 683         if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
 684                 return fs_info->dev_root;
 685         if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
 686                 return fs_info->csum_root;
 687
 688         BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
 689                location->offset != (u64)-1);
 690
 691         node = rb_search(&fs_info->fs_root_tree, (void *)&location->objectid,
 692                          btrfs_fs_roots_compare_objectids, NULL);
 693         if (node)
 694                 return container_of(node, struct btrfs_root, rb_node);
 695
 696         root = btrfs_read_fs_root_no_cache(fs_info, location);
 697         if (IS_ERR(root))
 698                 return root;
 699
 700         ret = rb_insert(&fs_info->fs_root_tree, &root->rb_node,
 701                         btrfs_fs_roots_compare_roots);
 702         BUG_ON(ret);
 703         return root;
 704 }
 705
 706 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
 707 {
 708         free(fs_info->tree_root);
 709         free(fs_info->extent_root);
 710         free(fs_info->chunk_root);
 711         free(fs_info->dev_root);
 712         free(fs_info->csum_root);
 713         free(fs_info->super_copy);
 714         free(fs_info->log_root_tree);
 715         free(fs_info);
 716 }
 717
 718 struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr)
 719 {
 720         struct btrfs_fs_info *fs_info;
 721
 722         fs_info = malloc(sizeof(struct btrfs_fs_info));
 723         if (!fs_info)
 724                 return NULL;
 725
 726         memset(fs_info, 0, sizeof(struct btrfs_fs_info));
 727
 728         fs_info->tree_root = malloc(sizeof(struct btrfs_root));
 729         fs_info->extent_root = malloc(sizeof(struct btrfs_root));
 730         fs_info->chunk_root = malloc(sizeof(struct btrfs_root));
 731         fs_info->dev_root = malloc(sizeof(struct btrfs_root));
 732         fs_info->csum_root = malloc(sizeof(struct btrfs_root));
 733         fs_info->super_copy = malloc(BTRFS_SUPER_INFO_SIZE);
 734
 735         if (!fs_info->tree_root || !fs_info->extent_root ||
 736             !fs_info->chunk_root || !fs_info->dev_root ||
 737             !fs_info->csum_root || !fs_info->super_copy)
 738                 goto free_all;
 739
 740         memset(fs_info->super_copy, 0, BTRFS_SUPER_INFO_SIZE);
 741         memset(fs_info->tree_root, 0, sizeof(struct btrfs_root));
 742         memset(fs_info->extent_root, 0, sizeof(struct btrfs_root));
 743         memset(fs_info->chunk_root, 0, sizeof(struct btrfs_root));
 744         memset(fs_info->dev_root, 0, sizeof(struct btrfs_root));
 745         memset(fs_info->csum_root, 0, sizeof(struct btrfs_root));
 746
 747         extent_io_tree_init(&fs_info->extent_cache);
 748         extent_io_tree_init(&fs_info->free_space_cache);
 749         extent_io_tree_init(&fs_info->block_group_cache);
 750         extent_io_tree_init(&fs_info->pinned_extents);
 751         extent_io_tree_init(&fs_info->pending_del);
 752         extent_io_tree_init(&fs_info->extent_ins);
 753         fs_info->fs_root_tree = RB_ROOT;
 754         cache_tree_init(&fs_info->mapping_tree.cache_tree);
 755
 756         mutex_init(&fs_info->fs_mutex);
 757         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
 758         INIT_LIST_HEAD(&fs_info->space_info);
 759         INIT_LIST_HEAD(&fs_info->recow_ebs);
 760
 761         if (!writable)
 762                 fs_info->readonly = 1;
 763
 764         fs_info->super_bytenr = sb_bytenr;
 765         fs_info->data_alloc_profile = (u64)-1;
 766         fs_info->metadata_alloc_profile = (u64)-1;
 767         fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
 768         return fs_info;
 769 free_all:
 770         btrfs_free_fs_info(fs_info);
 771         return NULL;
 772 }
 773
 774 int btrfs_check_fs_compatibility(struct btrfs_super_block *sb, int writable)
 775 {
 776         u64 features;
 777
 778         features = btrfs_super_incompat_flags(sb) &
 779                    ~BTRFS_FEATURE_INCOMPAT_SUPP;
 780         if (features) {
 781                 printk("couldn't open because of unsupported "
 782                        "option features (%Lx).\n",
 783                        (unsigned long long)features);
 784                 return -ENOTSUP;
 785         }
 786
 787         features = btrfs_super_incompat_flags(sb);
 788         if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
 789                 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
 790                 btrfs_set_super_incompat_flags(sb, features);
 791         }
 792
 793         features = btrfs_super_compat_ro_flags(sb) &
 794                 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
 795         if (writable && features) {
 796                 printk("couldn't open RDWR because of unsupported "
 797                        "option features (%Lx).\n",
 798                        (unsigned long long)features);
 799                 return -ENOTSUP;
 800         }
 801         return 0;
 802 }
 803
 804 int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info,
 805                           u64 root_tree_bytenr, int partial)
 806 {
 807         struct btrfs_super_block *sb = fs_info->super_copy;
 808         struct btrfs_root *root;
 809         struct btrfs_key key;
 810         u32 sectorsize;
 811         u32 nodesize;
 812         u32 leafsize;
 813         u32 stripesize;
 814         u64 generation;
 815         u32 blocksize;
 816         int ret;
 817
 818         nodesize = btrfs_super_nodesize(sb);
 819         leafsize = btrfs_super_leafsize(sb);
 820         sectorsize = btrfs_super_sectorsize(sb);
 821         stripesize = btrfs_super_stripesize(sb);
 822
 823         root = fs_info->tree_root;
 824         __setup_root(nodesize, leafsize, sectorsize, stripesize,
 825                      root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
 826         blocksize = btrfs_level_size(root, btrfs_super_root_level(sb));
 827         generation = btrfs_super_generation(sb);
 828
 829         if (!root_tree_bytenr)
 830                 root_tree_bytenr = btrfs_super_root(sb);
 831         root->node = read_tree_block(root, root_tree_bytenr, blocksize,
 832                                      generation);
 833         if (!extent_buffer_uptodate(root->node)) {
 834                 fprintf(stderr, "Couldn't read tree root\n");
 835                 return -EIO;
 836         }
 837
 838         ret = find_and_setup_root(root, fs_info, BTRFS_EXTENT_TREE_OBJECTID,
 839                                   fs_info->extent_root);
 840         if (ret) {
 841                 printk("Couldn't setup extent tree\n");
 842                 return -EIO;
 843         }
 844         fs_info->extent_root->track_dirty = 1;
 845
 846         ret = find_and_setup_root(root, fs_info, BTRFS_DEV_TREE_OBJECTID,
 847                                   fs_info->dev_root);
 848         if (ret) {
 849                 printk("Couldn't setup device tree\n");
 850                 return -EIO;
 851         }
 852         fs_info->dev_root->track_dirty = 1;
 853
 854         ret = find_and_setup_root(root, fs_info, BTRFS_CSUM_TREE_OBJECTID,
 855                                   fs_info->csum_root);
 856         if (ret) {
 857                 printk("Couldn't setup csum tree\n");
 858                 if (!partial)
 859                         return -EIO;
 860         }
 861         fs_info->csum_root->track_dirty = 1;
 862
 863         ret = find_and_setup_log_root(root, fs_info, sb);
 864         if (ret) {
 865                 printk("Couldn't setup log root tree\n");
 866                 return -EIO;
 867         }
 868
 869         fs_info->generation = generation;
 870         fs_info->last_trans_committed = generation;
 871         btrfs_read_block_groups(fs_info->tree_root);
 872
 873         key.objectid = BTRFS_FS_TREE_OBJECTID;
 874         key.type = BTRFS_ROOT_ITEM_KEY;
 875         key.offset = (u64)-1;
 876         fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
 877
 878         if (!fs_info->fs_root)
 879                 return -EIO;
 880         return 0;
 881 }
 882
 883 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info)
 884 {
 885         if (fs_info->csum_root)
 886                 free_extent_buffer(fs_info->csum_root->node);
 887         if (fs_info->dev_root)
 888                 free_extent_buffer(fs_info->dev_root->node);
 889         if (fs_info->extent_root)
 890                 free_extent_buffer(fs_info->extent_root->node);
 891         if (fs_info->tree_root)
 892                 free_extent_buffer(fs_info->tree_root->node);
 893         if (fs_info->log_root_tree)
 894                 free_extent_buffer(fs_info->log_root_tree->node);
 895         if (fs_info->chunk_root)
 896                 free_extent_buffer(fs_info->chunk_root->node);
 897 }
 898
 899 static void free_map_lookup(struct cache_extent *ce)
 900 {
 901         struct map_lookup *map;
 902
 903         map = container_of(ce, struct map_lookup, ce);
 904         kfree(map);
 905 }
 906
 907 FREE_EXTENT_CACHE_BASED_TREE(mapping_cache, free_map_lookup);
 908
 909 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info)
 910 {
 911         while (!list_empty(&fs_info->recow_ebs)) {
 912                 struct extent_buffer *eb;
 913                 eb = list_first_entry(&fs_info->recow_ebs,
 914                                       struct extent_buffer, recow);
 915                 list_del_init(&eb->recow);
 916                 free_extent_buffer(eb);
 917         }
 918         free_mapping_cache_tree(&fs_info->mapping_tree.cache_tree);
 919         extent_io_tree_cleanup(&fs_info->extent_cache);
 920         extent_io_tree_cleanup(&fs_info->free_space_cache);
 921         extent_io_tree_cleanup(&fs_info->block_group_cache);
 922         extent_io_tree_cleanup(&fs_info->pinned_extents);
 923         extent_io_tree_cleanup(&fs_info->pending_del);
 924         extent_io_tree_cleanup(&fs_info->extent_ins);
 925 }
 926
 927 int btrfs_scan_fs_devices(int fd, const char *path,
 928                           struct btrfs_fs_devices **fs_devices,
 929                           u64 sb_bytenr, int run_ioctl)
 930 {
 931         u64 total_devs;
 932         int ret;
 933         if (!sb_bytenr)
 934                 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
 935
 936         ret = btrfs_scan_one_device(fd, path, fs_devices,
 937                                     &total_devs, sb_bytenr);
 938         if (ret) {
 939                 fprintf(stderr, "No valid Btrfs found on %s\n", path);
 940                 return ret;
 941         }
 942
 943         if (total_devs != 1) {
 944                 ret = btrfs_scan_for_fsid(run_ioctl);
 945                 if (ret)
 946                         return ret;
 947         }
 948         return 0;
 949 }
 950
 951 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info)
 952 {
 953         struct btrfs_super_block *sb = fs_info->super_copy;
 954         u32 sectorsize;
 955         u32 nodesize;
 956         u32 leafsize;
 957         u32 blocksize;
 958         u32 stripesize;
 959         u64 generation;
 960         int ret;
 961
 962         nodesize = btrfs_super_nodesize(sb);
 963         leafsize = btrfs_super_leafsize(sb);
 964         sectorsize = btrfs_super_sectorsize(sb);
 965         stripesize = btrfs_super_stripesize(sb);
 966
 967         __setup_root(nodesize, leafsize, sectorsize, stripesize,
 968                      fs_info->chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
 969
 970         ret = btrfs_read_sys_array(fs_info->chunk_root);
 971         if (ret)
 972                 return ret;
 973
 974         blocksize = btrfs_level_size(fs_info->chunk_root,
 975                                      btrfs_super_chunk_root_level(sb));
 976         generation = btrfs_super_chunk_root_generation(sb);
 977
 978         fs_info->chunk_root->node = read_tree_block(fs_info->chunk_root,
 979                                                     btrfs_super_chunk_root(sb),
 980                                                     blocksize, generation);
 981         if (!fs_info->chunk_root->node ||
 982             !extent_buffer_uptodate(fs_info->chunk_root->node)) {
 983                 fprintf(stderr, "Couldn't read chunk root\n");
 984                 return -EIO;
 985         }
 986
 987         if (!(btrfs_super_flags(sb) & BTRFS_SUPER_FLAG_METADUMP)) {
 988                 ret = btrfs_read_chunk_tree(fs_info->chunk_root);
 989                 if (ret) {
 990                         fprintf(stderr, "Couldn't read chunk tree\n");
 991                         return ret;
 992                 }
 993         }
 994         return 0;
 995 }
 996
 997 static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
 998                                              u64 sb_bytenr,
 999                                              u64 root_tree_bytenr, int writes,
1000                                              int partial, int restore,
1001                                              int recover_super)
1002 {
1003         struct btrfs_fs_info *fs_info;
1004         struct btrfs_super_block *disk_super;
1005         struct btrfs_fs_devices *fs_devices = NULL;
1006         struct extent_buffer *eb;
1007         int ret;
1008
1009         if (sb_bytenr == 0)
1010                 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1011
1012         /* try to drop all the caches */
1013         if (posix_fadvise(fp, 0, 0, POSIX_FADV_DONTNEED))
1014                 fprintf(stderr, "Warning, could not drop caches\n");
1015
1016         fs_info = btrfs_new_fs_info(writes, sb_bytenr);
1017         if (!fs_info) {
1018                 fprintf(stderr, "Failed to allocate memory for fs_info\n");
1019                 return NULL;
1020         }
1021         if (restore)
1022                 fs_info->on_restoring = 1;
1023
1024         ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr,
1025                                     !recover_super);
1026         if (ret)
1027                 goto out;
1028
1029         fs_info->fs_devices = fs_devices;
1030         if (writes)
1031                 ret = btrfs_open_devices(fs_devices, O_RDWR);
1032         else
1033                 ret = btrfs_open_devices(fs_devices, O_RDONLY);
1034         if (ret)
1035                 goto out_devices;
1036
1037
1038         disk_super = fs_info->super_copy;
1039         if (!recover_super)
1040                 ret = btrfs_read_dev_super(fs_devices->latest_bdev,
1041                                            disk_super, sb_bytenr);
1042         else
1043                 ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr);
1044         if (ret) {
1045                 printk("No valid btrfs found\n");
1046                 goto out_devices;
1047         }
1048
1049         memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
1050
1051         ret = btrfs_check_fs_compatibility(fs_info->super_copy, writes);
1052         if (ret)
1053                 goto out_devices;
1054
1055         ret = btrfs_setup_chunk_tree_and_device_map(fs_info);
1056         if (ret)
1057                 goto out_chunk;
1058
1059         eb = fs_info->chunk_root->node;
1060         read_extent_buffer(eb, fs_info->chunk_tree_uuid,
1061                            (unsigned long)btrfs_header_chunk_tree_uuid(eb),
1062                            BTRFS_UUID_SIZE);
1063
1064         ret = btrfs_setup_all_roots(fs_info, root_tree_bytenr, partial);
1065         if (ret)
1066                 goto out_failed;
1067
1068         return fs_info;
1069
1070 out_failed:
1071         if (partial)
1072                 return fs_info;
1073 out_chunk:
1074         btrfs_release_all_roots(fs_info);
1075         btrfs_cleanup_all_caches(fs_info);
1076 out_devices:
1077         btrfs_close_devices(fs_devices);
1078 out:
1079         btrfs_free_fs_info(fs_info);
1080         return NULL;
1081 }
1082
1083 struct btrfs_fs_info *open_ctree_fs_info_restore(const char *filename,
1084                                          u64 sb_bytenr, u64 root_tree_bytenr,
1085                                          int writes, int partial)
1086 {
1087         int fp;
1088         struct btrfs_fs_info *info;
1089         int flags = O_CREAT | O_RDWR;
1090         int restore = 1;
1091
1092         if (!writes)
1093                 flags = O_RDONLY;
1094
1095         fp = open(filename, flags, 0600);
1096         if (fp < 0) {
1097                 fprintf (stderr, "Could not open %s\n", filename);
1098                 return NULL;
1099         }
1100         info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
1101                                writes, partial, restore, 0);
1102         close(fp);
1103         return info;
1104 }
1105
1106 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
1107                                          u64 sb_bytenr, u64 root_tree_bytenr,
1108                                          int writes, int partial)
1109 {
1110         int fp;
1111         struct btrfs_fs_info *info;
1112         int flags = O_CREAT | O_RDWR;
1113
1114         if (!writes)
1115                 flags = O_RDONLY;
1116
1117         fp = open(filename, flags, 0600);
1118         if (fp < 0) {
1119                 fprintf (stderr, "Could not open %s\n", filename);
1120                 return NULL;
1121         }
1122         info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
1123                                writes, partial, 0, 0);
1124         close(fp);
1125         return info;
1126 }
1127
1128 struct btrfs_root *open_ctree_with_broken_super(const char *filename,
1129                                         u64 sb_bytenr, int writes)
1130 {
1131         int fp;
1132         struct btrfs_fs_info *info;
1133         int flags = O_CREAT | O_RDWR;
1134
1135         if (!writes)
1136                 flags = O_RDONLY;
1137
1138         fp = open(filename, flags, 0600);
1139         if (fp < 0) {
1140                 fprintf(stderr, "Could not open %s\n", filename);
1141                 return NULL;
1142         }
1143         info = __open_ctree_fd(fp, filename, sb_bytenr, 0,
1144                                writes, 0, 0, 1);
1145         close(fp);
1146         if (info)
1147                 return info->fs_root;
1148         return NULL;
1149 }
1150
1151 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr, int writes)
1152 {
1153         struct btrfs_fs_info *info;
1154
1155         info = open_ctree_fs_info(filename, sb_bytenr, 0, writes, 0);
1156         if (!info)
1157                 return NULL;
1158         return info->fs_root;
1159 }
1160
1161 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
1162                                  int writes)
1163 {
1164         struct btrfs_fs_info *info;
1165         info = __open_ctree_fd(fp, path, sb_bytenr, 0, writes, 0, 0, 0);
1166         if (!info)
1167                 return NULL;
1168         return info->fs_root;
1169 }
1170
1171 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr)
1172 {
1173         u8 fsid[BTRFS_FSID_SIZE];
1174         int fsid_is_initialized = 0;
1175         struct btrfs_super_block buf;
1176         int i;
1177         int ret;
1178         u64 transid = 0;
1179         u64 bytenr;
1180
1181         if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1182                 ret = pread64(fd, &buf, sizeof(buf), sb_bytenr);
1183                 if (ret < sizeof(buf))
1184                         return -1;
1185
1186                 if (btrfs_super_bytenr(&buf) != sb_bytenr ||
1187                     btrfs_super_magic(&buf) != BTRFS_MAGIC)
1188                         return -1;
1189
1190                 memcpy(sb, &buf, sizeof(*sb));
1191                 return 0;
1192         }
1193
1194         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1195                 bytenr = btrfs_sb_offset(i);
1196                 ret = pread64(fd, &buf, sizeof(buf), bytenr);
1197                 if (ret < sizeof(buf))
1198                         break;
1199
1200                 if (btrfs_super_bytenr(&buf) != bytenr )
1201                         continue;
1202                 /* if magic is NULL, the device was removed */
1203                 if (btrfs_super_magic(&buf) == 0 && i == 0)
1204                         return -1;
1205                 if (btrfs_super_magic(&buf) != BTRFS_MAGIC)
1206                         continue;
1207
1208                 if (!fsid_is_initialized) {
1209                         memcpy(fsid, buf.fsid, sizeof(fsid));
1210                         fsid_is_initialized = 1;
1211                 } else if (memcmp(fsid, buf.fsid, sizeof(fsid))) {
1212                         /*
1213                          * the superblocks (the original one and
1214                          * its backups) contain data of different
1215                          * filesystems -> the super cannot be trusted
1216                          */
1217                         continue;
1218                 }
1219
1220                 if (btrfs_super_generation(&buf) > transid) {
1221                         memcpy(sb, &buf, sizeof(*sb));
1222                         transid = btrfs_super_generation(&buf);
1223                 }
1224         }
1225
1226         return transid > 0 ? 0 : -1;
1227 }
1228
1229 static int write_dev_supers(struct btrfs_root *root,
1230                             struct btrfs_super_block *sb,
1231                             struct btrfs_device *device)
1232 {
1233         u64 bytenr;
1234         u32 crc;
1235         int i, ret;
1236
1237         if (root->fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1238                 btrfs_set_super_bytenr(sb, root->fs_info->super_bytenr);
1239                 crc = ~(u32)0;
1240                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1241                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1242                 btrfs_csum_final(crc, (char *)&sb->csum[0]);
1243
1244                 /*
1245                  * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1246                  * zero filled, we can use it directly
1247                  */
1248                 ret = pwrite64(device->fd, root->fs_info->super_copy,
1249                                 BTRFS_SUPER_INFO_SIZE,
1250                                 root->fs_info->super_bytenr);
1251                 BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
1252                 return 0;
1253         }
1254
1255         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1256                 bytenr = btrfs_sb_offset(i);
1257                 if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
1258                         break;
1259
1260                 btrfs_set_super_bytenr(sb, bytenr);
1261
1262                 crc = ~(u32)0;
1263                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1264                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1265                 btrfs_csum_final(crc, (char *)&sb->csum[0]);
1266
1267                 /*
1268                  * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1269                  * zero filled, we can use it directly
1270                  */
1271                 ret = pwrite64(device->fd, root->fs_info->super_copy,
1272                                 BTRFS_SUPER_INFO_SIZE, bytenr);
1273                 BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
1274         }
1275
1276         return 0;
1277 }
1278
1279 int write_all_supers(struct btrfs_root *root)
1280 {
1281         struct list_head *cur;
1282         struct list_head *head = &root->fs_info->fs_devices->devices;
1283         struct btrfs_device *dev;
1284         struct btrfs_super_block *sb;
1285         struct btrfs_dev_item *dev_item;
1286         int ret;
1287         u64 flags;
1288
1289         sb = root->fs_info->super_copy;
1290         dev_item = &sb->dev_item;
1291         list_for_each(cur, head) {
1292                 dev = list_entry(cur, struct btrfs_device, dev_list);
1293                 if (!dev->writeable)
1294                         continue;
1295
1296                 btrfs_set_stack_device_generation(dev_item, 0);
1297                 btrfs_set_stack_device_type(dev_item, dev->type);
1298                 btrfs_set_stack_device_id(dev_item, dev->devid);
1299                 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1300                 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1301                 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1302                 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1303                 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1304                 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1305                 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
1306
1307                 flags = btrfs_super_flags(sb);
1308                 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
1309
1310                 ret = write_dev_supers(root, sb, dev);
1311                 BUG_ON(ret);
1312         }
1313         return 0;
1314 }
1315
1316 int write_ctree_super(struct btrfs_trans_handle *trans,
1317                       struct btrfs_root *root)
1318 {
1319         int ret;
1320         struct btrfs_root *tree_root = root->fs_info->tree_root;
1321         struct btrfs_root *chunk_root = root->fs_info->chunk_root;
1322
1323         if (root->fs_info->readonly)
1324                 return 0;
1325
1326         btrfs_set_super_generation(root->fs_info->super_copy,
1327                                    trans->transid);
1328         btrfs_set_super_root(root->fs_info->super_copy,
1329                              tree_root->node->start);
1330         btrfs_set_super_root_level(root->fs_info->super_copy,
1331                                    btrfs_header_level(tree_root->node));
1332         btrfs_set_super_chunk_root(root->fs_info->super_copy,
1333                                    chunk_root->node->start);
1334         btrfs_set_super_chunk_root_level(root->fs_info->super_copy,
1335                                          btrfs_header_level(chunk_root->node));
1336         btrfs_set_super_chunk_root_generation(root->fs_info->super_copy,
1337                                 btrfs_header_generation(chunk_root->node));
1338
1339         ret = write_all_supers(root);
1340         if (ret)
1341                 fprintf(stderr, "failed to write new super block err %d\n", ret);
1342         return ret;
1343 }
1344
1345 int close_ctree(struct btrfs_root *root)
1346 {
1347         int ret;
1348         struct btrfs_trans_handle *trans;
1349         struct btrfs_fs_info *fs_info = root->fs_info;
1350
1351         if (fs_info->last_trans_committed !=
1352             fs_info->generation) {
1353                 trans = btrfs_start_transaction(root, 1);
1354                 btrfs_commit_transaction(trans, root);
1355                 trans = btrfs_start_transaction(root, 1);
1356                 ret = commit_tree_roots(trans, fs_info);
1357                 BUG_ON(ret);
1358                 ret = __commit_transaction(trans, root);
1359                 BUG_ON(ret);
1360                 write_ctree_super(trans, root);
1361                 btrfs_free_transaction(root, trans);
1362         }
1363         btrfs_free_block_groups(fs_info);
1364
1365         free_fs_roots_tree(&fs_info->fs_root_tree);
1366
1367         btrfs_release_all_roots(fs_info);
1368         btrfs_close_devices(fs_info->fs_devices);
1369         btrfs_cleanup_all_caches(fs_info);
1370         btrfs_free_fs_info(fs_info);
1371         return 0;
1372 }
1373
1374 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1375                      struct extent_buffer *eb)
1376 {
1377         return clear_extent_buffer_dirty(eb);
1378 }
1379
1380 int wait_on_tree_block_writeback(struct btrfs_root *root,
1381                                  struct extent_buffer *eb)
1382 {
1383         return 0;
1384 }
1385
1386 void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
1387 {
1388         set_extent_buffer_dirty(eb);
1389 }
1390
1391 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1392 {
1393         int ret;
1394
1395         ret = extent_buffer_uptodate(buf);
1396         if (!ret)
1397                 return ret;
1398
1399         ret = verify_parent_transid(buf->tree, buf, parent_transid, 1);
1400         return !ret;
1401 }
1402
1403 int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
1404 {
1405         return set_extent_buffer_uptodate(eb);
1406 }