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                 return ret;
  46
  47         fs_devices = root->fs_info->fs_devices;
  48         while (fs_devices) {
  49                 if (!memcmp_extent_buffer(buf, fs_devices->fsid,
  50                                           (unsigned long)btrfs_header_fsid(buf),
  51                                           BTRFS_FSID_SIZE)) {
  52                         ret = 0;
  53                         break;
  54                 }
  55                 fs_devices = fs_devices->seed;
  56         }
  57         return ret;
  58 }
  59
  60 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
  61 {
  62         return crc32c(seed, data, len);
  63 }
  64
  65 void btrfs_csum_final(u32 crc, char *result)
  66 {
  67         *(__le32 *)result = ~cpu_to_le32(crc);
  68 }
  69
  70 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
  71                          int verify)
  72 {
  73         char *result;
  74         u32 len;
  75         u32 crc = ~(u32)0;
  76
  77         result = malloc(csum_size * sizeof(char));
  78         if (!result)
  79                 return 1;
  80
  81         len = buf->len - BTRFS_CSUM_SIZE;
  82         crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len);
  83         btrfs_csum_final(crc, result);
  84
  85         if (verify) {
  86                 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
  87                         printk("checksum verify failed on %llu wanted %X "
  88                                "found %X\n", (unsigned long long)buf->start,
  89                                *((int *)result), *((char *)buf->data));
  90                         free(result);
  91                         return 1;
  92                 }
  93         } else {
  94                 write_extent_buffer(buf, result, 0, csum_size);
  95         }
  96         free(result);
  97         return 0;
  98 }
  99
 100 int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 101                     int verify)
 102 {
 103         u16 csum_size =
 104                 btrfs_super_csum_size(&root->fs_info->super_copy);
 105         return csum_tree_block_size(buf, csum_size, verify);
 106 }
 107
 108 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
 109                                             u64 bytenr, u32 blocksize)
 110 {
 111         return find_extent_buffer(&root->fs_info->extent_cache,
 112                                   bytenr, blocksize);
 113 }
 114
 115 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
 116                                                  u64 bytenr, u32 blocksize)
 117 {
 118         return alloc_extent_buffer(&root->fs_info->extent_cache, bytenr,
 119                                    blocksize);
 120 }
 121
 122 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
 123                          u64 parent_transid)
 124 {
 125         int ret;
 126         int dev_nr;
 127         struct extent_buffer *eb;
 128         u64 length;
 129         struct btrfs_multi_bio *multi = NULL;
 130         struct btrfs_device *device;
 131
 132         eb = btrfs_find_tree_block(root, bytenr, blocksize);
 133         if (eb && btrfs_buffer_uptodate(eb, parent_transid)) {
 134                 free_extent_buffer(eb);
 135                 return 0;
 136         }
 137
 138         dev_nr = 0;
 139         length = blocksize;
 140         ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
 141                               bytenr, &length, &multi, 0);
 142         BUG_ON(ret);
 143         device = multi->stripes[0].dev;
 144         device->total_ios++;
 145         blocksize = min(blocksize, (u32)(64 * 1024));
 146         readahead(device->fd, multi->stripes[0].physical, blocksize);
 147         kfree(multi);
 148         return 0;
 149 }
 150
 151 static int verify_parent_transid(struct extent_io_tree *io_tree,
 152                                  struct extent_buffer *eb, u64 parent_transid)
 153 {
 154         int ret;
 155
 156         if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 157                 return 0;
 158
 159         if (extent_buffer_uptodate(eb) &&
 160             btrfs_header_generation(eb) == parent_transid) {
 161                 ret = 0;
 162                 goto out;
 163         }
 164         printk("parent transid verify failed on %llu wanted %llu found %llu\n",
 165                (unsigned long long)eb->start,
 166                (unsigned long long)parent_transid,
 167                (unsigned long long)btrfs_header_generation(eb));
 168         ret = 1;
 169 out:
 170         clear_extent_buffer_uptodate(io_tree, eb);
 171         return ret;
 172
 173 }
 174
 175
 176 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 177                                      u32 blocksize, u64 parent_transid)
 178 {
 179         int ret;
 180         int dev_nr;
 181         struct extent_buffer *eb;
 182         u64 length;
 183         struct btrfs_multi_bio *multi = NULL;
 184         struct btrfs_device *device;
 185         int mirror_num = 0;
 186         int num_copies;
 187
 188         eb = btrfs_find_create_tree_block(root, bytenr, blocksize);
 189         if (!eb)
 190                 return NULL;
 191
 192         if (btrfs_buffer_uptodate(eb, parent_transid))
 193                 return eb;
 194
 195         dev_nr = 0;
 196         length = blocksize;
 197         while (1) {
 198                 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
 199                                       eb->start, &length, &multi, mirror_num);
 200                 BUG_ON(ret);
 201                 device = multi->stripes[0].dev;
 202                 eb->fd = device->fd;
 203                 device->total_ios++;
 204                 eb->dev_bytenr = multi->stripes[0].physical;
 205                 kfree(multi);
 206                 ret = read_extent_from_disk(eb);
 207
 208                 if (ret == 0 && check_tree_block(root, eb) == 0 &&
 209                     csum_tree_block(root, eb, 1) == 0 &&
 210                     verify_parent_transid(eb->tree, eb, parent_transid) == 0) {
 211                         btrfs_set_buffer_uptodate(eb);
 212                         return eb;
 213                 }
 214                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 215                                               eb->start, eb->len);
 216                 if (num_copies == 1) {
 217                         break;
 218                 }
 219                 mirror_num++;
 220                 if (mirror_num > num_copies) {
 221                         break;
 222                 }
 223         }
 224         free_extent_buffer(eb);
 225         return NULL;
 226 }
 227
 228 int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 229                      struct extent_buffer *eb)
 230 {
 231         int ret;
 232         int dev_nr;
 233         u64 length;
 234         struct btrfs_multi_bio *multi = NULL;
 235
 236         if (check_tree_block(root, eb))
 237                 BUG();
 238         if (!btrfs_buffer_uptodate(eb, trans->transid))
 239                 BUG();
 240
 241         btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
 242         csum_tree_block(root, eb, 0);
 243
 244         dev_nr = 0;
 245         length = eb->len;
 246         ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE,
 247                               eb->start, &length, &multi, 0);
 248
 249         while(dev_nr < multi->num_stripes) {
 250                 BUG_ON(ret);
 251                 eb->fd = multi->stripes[dev_nr].dev->fd;
 252                 eb->dev_bytenr = multi->stripes[dev_nr].physical;
 253                 multi->stripes[dev_nr].dev->total_ios++;
 254                 dev_nr++;
 255                 ret = write_extent_to_disk(eb);
 256                 BUG_ON(ret);
 257         }
 258         kfree(multi);
 259         return 0;
 260 }
 261
 262 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 263                         u32 stripesize, struct btrfs_root *root,
 264                         struct btrfs_fs_info *fs_info, u64 objectid)
 265 {
 266         root->node = NULL;
 267         root->commit_root = NULL;
 268         root->sectorsize = sectorsize;
 269         root->nodesize = nodesize;
 270         root->leafsize = leafsize;
 271         root->stripesize = stripesize;
 272         root->ref_cows = 0;
 273         root->track_dirty = 0;
 274
 275         root->fs_info = fs_info;
 276         root->objectid = objectid;
 277         root->last_trans = 0;
 278         root->highest_inode = 0;
 279         root->last_inode_alloc = 0;
 280
 281         INIT_LIST_HEAD(&root->dirty_list);
 282         memset(&root->root_key, 0, sizeof(root->root_key));
 283         memset(&root->root_item, 0, sizeof(root->root_item));
 284         root->root_key.objectid = objectid;
 285         return 0;
 286 }
 287
 288 static int update_cowonly_root(struct btrfs_trans_handle *trans,
 289                                struct btrfs_root *root)
 290 {
 291         int ret;
 292         u64 old_root_bytenr;
 293         struct btrfs_root *tree_root = root->fs_info->tree_root;
 294
 295         btrfs_write_dirty_block_groups(trans, root);
 296         while(1) {
 297                 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
 298                 if (old_root_bytenr == root->node->start)
 299                         break;
 300                 btrfs_set_root_bytenr(&root->root_item,
 301                                        root->node->start);
 302                 btrfs_set_root_generation(&root->root_item,
 303                                           trans->transid);
 304                 root->root_item.level = btrfs_header_level(root->node);
 305                 ret = btrfs_update_root(trans, tree_root,
 306                                         &root->root_key,
 307                                         &root->root_item);
 308                 BUG_ON(ret);
 309                 btrfs_write_dirty_block_groups(trans, root);
 310         }
 311         return 0;
 312 }
 313
 314 static int commit_tree_roots(struct btrfs_trans_handle *trans,
 315                              struct btrfs_fs_info *fs_info)
 316 {
 317         struct btrfs_root *root;
 318         struct list_head *next;
 319         struct extent_buffer *eb;
 320
 321         if (fs_info->readonly)
 322                 return 0;
 323
 324         eb = fs_info->tree_root->node;
 325         extent_buffer_get(eb);
 326         btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
 327         free_extent_buffer(eb);
 328
 329         while(!list_empty(&fs_info->dirty_cowonly_roots)) {
 330                 next = fs_info->dirty_cowonly_roots.next;
 331                 list_del_init(next);
 332                 root = list_entry(next, struct btrfs_root, dirty_list);
 333                 update_cowonly_root(trans, root);
 334         }
 335         return 0;
 336 }
 337
 338 static int __commit_transaction(struct btrfs_trans_handle *trans,
 339                                 struct btrfs_root *root)
 340 {
 341         u64 start;
 342         u64 end;
 343         struct extent_buffer *eb;
 344         struct extent_io_tree *tree = &root->fs_info->extent_cache;
 345         int ret;
 346
 347         while(1) {
 348                 ret = find_first_extent_bit(tree, 0, &start, &end,
 349                                             EXTENT_DIRTY);
 350                 if (ret)
 351                         break;
 352                 while(start <= end) {
 353                         eb = find_first_extent_buffer(tree, start);
 354                         BUG_ON(!eb || eb->start != start);
 355                         ret = write_tree_block(trans, root, eb);
 356                         BUG_ON(ret);
 357                         start += eb->len;
 358                         clear_extent_buffer_dirty(eb);
 359                         free_extent_buffer(eb);
 360                 }
 361         }
 362         return 0;
 363 }
 364
 365 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 366                              struct btrfs_root *root)
 367 {
 368         int ret = 0;
 369         struct btrfs_fs_info *fs_info = root->fs_info;
 370
 371         if (root->commit_root == root->node)
 372                 goto commit_tree;
 373
 374         free_extent_buffer(root->commit_root);
 375         root->commit_root = NULL;
 376
 377         btrfs_set_root_bytenr(&root->root_item, root->node->start);
 378         btrfs_set_root_generation(&root->root_item, trans->transid);
 379         root->root_item.level = btrfs_header_level(root->node);
 380         ret = btrfs_update_root(trans, root->fs_info->tree_root,
 381                                 &root->root_key, &root->root_item);
 382         BUG_ON(ret);
 383 commit_tree:
 384         ret = commit_tree_roots(trans, fs_info);
 385         BUG_ON(ret);
 386         ret = __commit_transaction(trans, root);
 387         BUG_ON(ret);
 388         write_ctree_super(trans, root);
 389         btrfs_finish_extent_commit(trans, fs_info->extent_root,
 390                                    &fs_info->pinned_extents);
 391         btrfs_free_transaction(root, trans);
 392         free_extent_buffer(root->commit_root);
 393         root->commit_root = NULL;
 394         fs_info->running_transaction = NULL;
 395         return 0;
 396 }
 397
 398 static int find_and_setup_root(struct btrfs_root *tree_root,
 399                                struct btrfs_fs_info *fs_info,
 400                                u64 objectid, struct btrfs_root *root)
 401 {
 402         int ret;
 403         u32 blocksize;
 404         u64 generation;
 405
 406         __setup_root(tree_root->nodesize, tree_root->leafsize,
 407                      tree_root->sectorsize, tree_root->stripesize,
 408                      root, fs_info, objectid);
 409         ret = btrfs_find_last_root(tree_root, objectid,
 410                                    &root->root_item, &root->root_key);
 411         BUG_ON(ret);
 412
 413         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 414         generation = btrfs_root_generation(&root->root_item);
 415         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 416                                      blocksize, generation);
 417         BUG_ON(!root->node);
 418         return 0;
 419 }
 420
 421 static int find_and_setup_log_root(struct btrfs_root *tree_root,
 422                                struct btrfs_fs_info *fs_info,
 423                                struct btrfs_super_block *disk_super)
 424 {
 425         u32 blocksize;
 426         u64 blocknr = btrfs_super_log_root(disk_super);
 427         struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
 428
 429         if (blocknr == 0)
 430                 return 0;
 431
 432         blocksize = btrfs_level_size(tree_root,
 433                              btrfs_super_log_root_level(disk_super));
 434
 435         __setup_root(tree_root->nodesize, tree_root->leafsize,
 436                      tree_root->sectorsize, tree_root->stripesize,
 437                      log_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
 438
 439         log_root->node = read_tree_block(tree_root, blocknr,
 440                                      blocksize,
 441                                      btrfs_super_generation(disk_super) + 1);
 442
 443         fs_info->log_root_tree = log_root;
 444         BUG_ON(!log_root->node);
 445         return 0;
 446 }
 447
 448
 449 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info,
 450                        struct btrfs_root *root)
 451 {
 452         if (root->node)
 453                 free_extent_buffer(root->node);
 454         if (root->commit_root)
 455                 free_extent_buffer(root->commit_root);
 456         kfree(root);
 457         return 0;
 458 }
 459
 460 static int free_fs_roots(struct btrfs_fs_info *fs_info)
 461 {
 462         struct cache_extent *cache;
 463         struct btrfs_root *root;
 464
 465         while (1) {
 466                 cache = find_first_cache_extent(&fs_info->fs_root_cache, 0);
 467                 if (!cache)
 468                         break;
 469                 root = container_of(cache, struct btrfs_root, cache);
 470                 remove_cache_extent(&fs_info->fs_root_cache, cache);
 471                 btrfs_free_fs_root(fs_info, root);
 472         }
 473         return 0;
 474 }
 475
 476 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
 477                                                struct btrfs_key *location)
 478 {
 479         struct btrfs_root *root;
 480         struct btrfs_root *tree_root = fs_info->tree_root;
 481         struct btrfs_path *path;
 482         struct extent_buffer *l;
 483         u64 generation;
 484         u32 blocksize;
 485         int ret = 0;
 486
 487         root = malloc(sizeof(*root));
 488         if (!root)
 489                 return ERR_PTR(-ENOMEM);
 490         memset(root, 0, sizeof(*root));
 491         if (location->offset == (u64)-1) {
 492                 ret = find_and_setup_root(tree_root, fs_info,
 493                                           location->objectid, root);
 494                 if (ret) {
 495                         free(root);
 496                         return ERR_PTR(ret);
 497                 }
 498                 goto insert;
 499         }
 500
 501         __setup_root(tree_root->nodesize, tree_root->leafsize,
 502                      tree_root->sectorsize, tree_root->stripesize,
 503                      root, fs_info, location->objectid);
 504
 505         path = btrfs_alloc_path();
 506         BUG_ON(!path);
 507         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
 508         if (ret != 0) {
 509                 if (ret > 0)
 510                         ret = -ENOENT;
 511                 goto out;
 512         }
 513         l = path->nodes[0];
 514         read_extent_buffer(l, &root->root_item,
 515                btrfs_item_ptr_offset(l, path->slots[0]),
 516                sizeof(root->root_item));
 517         memcpy(&root->root_key, location, sizeof(*location));
 518         ret = 0;
 519 out:
 520         btrfs_release_path(root, path);
 521         btrfs_free_path(path);
 522         if (ret) {
 523                 free(root);
 524                 return ERR_PTR(ret);
 525         }
 526         generation = btrfs_root_generation(&root->root_item);
 527         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 528         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 529                                      blocksize, generation);
 530         BUG_ON(!root->node);
 531 insert:
 532         root->ref_cows = 1;
 533         return root;
 534 }
 535
 536 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 537                                       struct btrfs_key *location)
 538 {
 539         struct btrfs_root *root;
 540         struct cache_extent *cache;
 541         int ret;
 542
 543         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
 544                 return fs_info->tree_root;
 545         if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
 546                 return fs_info->extent_root;
 547         if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
 548                 return fs_info->chunk_root;
 549         if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
 550                 return fs_info->dev_root;
 551         if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
 552                 return fs_info->csum_root;
 553
 554         BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
 555                location->offset != (u64)-1);
 556
 557         cache = find_cache_extent(&fs_info->fs_root_cache,
 558                                   location->objectid, 1);
 559         if (cache)
 560                 return container_of(cache, struct btrfs_root, cache);
 561
 562         root = btrfs_read_fs_root_no_cache(fs_info, location);
 563         if (IS_ERR(root))
 564                 return root;
 565
 566         root->cache.start = location->objectid;
 567         root->cache.size = 1;
 568         ret = insert_existing_cache_extent(&fs_info->fs_root_cache,
 569                                            &root->cache);
 570         BUG_ON(ret);
 571         return root;
 572 }
 573
 574 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr, int writes)
 575 {
 576         int fp;
 577         struct btrfs_root *root;
 578         int flags = O_CREAT | O_RDWR;
 579
 580         if (!writes)
 581                 flags = O_RDONLY;
 582
 583         fp = open(filename, flags, 0600);
 584         if (fp < 0) {
 585                 fprintf (stderr, "Could not open %s\n", filename);
 586                 return NULL;
 587         }
 588         root = open_ctree_fd(fp, filename, sb_bytenr, writes);
 589         close(fp);
 590
 591         return root;
 592 }
 593
 594 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
 595                                  int writes)
 596 {
 597         u32 sectorsize;
 598         u32 nodesize;
 599         u32 leafsize;
 600         u32 blocksize;
 601         u32 stripesize;
 602         u64 generation;
 603         struct btrfs_key key;
 604         struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
 605         struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
 606         struct btrfs_root *chunk_root = malloc(sizeof(struct btrfs_root));
 607         struct btrfs_root *dev_root = malloc(sizeof(struct btrfs_root));
 608         struct btrfs_root *csum_root = malloc(sizeof(struct btrfs_root));
 609         struct btrfs_fs_info *fs_info = malloc(sizeof(*fs_info));
 610         int ret;
 611         struct btrfs_super_block *disk_super;
 612         struct btrfs_fs_devices *fs_devices = NULL;
 613         u64 total_devs;
 614         u64 features;
 615
 616         if (sb_bytenr == 0)
 617                 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
 618
 619         ret = btrfs_scan_one_device(fp, path, &fs_devices,
 620                                     &total_devs, sb_bytenr);
 621
 622         if (ret) {
 623                 fprintf(stderr, "No valid Btrfs found on %s\n", path);
 624                 return NULL;
 625         }
 626
 627         if (total_devs != 1) {
 628                 ret = btrfs_scan_for_fsid(fs_devices, total_devs, 1);
 629                 BUG_ON(ret);
 630         }
 631
 632         memset(fs_info, 0, sizeof(*fs_info));
 633         fs_info->tree_root = tree_root;
 634         fs_info->extent_root = extent_root;
 635         fs_info->chunk_root = chunk_root;
 636         fs_info->dev_root = dev_root;
 637         fs_info->csum_root = csum_root;
 638
 639         if (!writes)
 640                 fs_info->readonly = 1;
 641
 642         extent_io_tree_init(&fs_info->extent_cache);
 643         extent_io_tree_init(&fs_info->free_space_cache);
 644         extent_io_tree_init(&fs_info->block_group_cache);
 645         extent_io_tree_init(&fs_info->pinned_extents);
 646         extent_io_tree_init(&fs_info->pending_del);
 647         extent_io_tree_init(&fs_info->extent_ins);
 648         cache_tree_init(&fs_info->fs_root_cache);
 649
 650         cache_tree_init(&fs_info->mapping_tree.cache_tree);
 651
 652         mutex_init(&fs_info->fs_mutex);
 653         fs_info->fs_devices = fs_devices;
 654         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
 655         INIT_LIST_HEAD(&fs_info->space_info);
 656
 657         __setup_root(4096, 4096, 4096, 4096, tree_root,
 658                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 659
 660         if (writes)
 661                 ret = btrfs_open_devices(fs_devices, O_RDWR);
 662         else
 663                 ret = btrfs_open_devices(fs_devices, O_RDONLY);
 664         BUG_ON(ret);
 665
 666         fs_info->super_bytenr = sb_bytenr;
 667         disk_super = &fs_info->super_copy;
 668         ret = btrfs_read_dev_super(fs_devices->latest_bdev,
 669                                    disk_super, sb_bytenr);
 670         if (ret) {
 671                 printk("No valid btrfs found\n");
 672                 BUG_ON(1);
 673         }
 674
 675         memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
 676
 677
 678         features = btrfs_super_incompat_flags(disk_super) &
 679                    ~BTRFS_FEATURE_INCOMPAT_SUPP;
 680         if (features) {
 681                 printk("couldn't open because of unsupported "
 682                        "option features (%Lx).\n", features);
 683                 BUG_ON(1);
 684         }
 685
 686         features = btrfs_super_incompat_flags(disk_super);
 687         if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
 688                 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
 689                 btrfs_set_super_incompat_flags(disk_super, features);
 690         }
 691
 692         features = btrfs_super_compat_ro_flags(disk_super) &
 693                 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
 694         if (writes && features) {
 695                 printk("couldn't open RDWR because of unsupported "
 696                        "option features (%Lx).\n", features);
 697                 BUG_ON(1);
 698         }
 699
 700         nodesize = btrfs_super_nodesize(disk_super);
 701         leafsize = btrfs_super_leafsize(disk_super);
 702         sectorsize = btrfs_super_sectorsize(disk_super);
 703         stripesize = btrfs_super_stripesize(disk_super);
 704         tree_root->nodesize = nodesize;
 705         tree_root->leafsize = leafsize;
 706         tree_root->sectorsize = sectorsize;
 707         tree_root->stripesize = stripesize;
 708
 709         ret = btrfs_read_sys_array(tree_root);
 710         BUG_ON(ret);
 711         blocksize = btrfs_level_size(tree_root,
 712                                      btrfs_super_chunk_root_level(disk_super));
 713         generation = btrfs_super_chunk_root_generation(disk_super);
 714
 715         __setup_root(nodesize, leafsize, sectorsize, stripesize,
 716                      chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
 717
 718         chunk_root->node = read_tree_block(chunk_root,
 719                                            btrfs_super_chunk_root(disk_super),
 720                                            blocksize, generation);
 721
 722         BUG_ON(!chunk_root->node);
 723
 724         read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
 725                  (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
 726                  BTRFS_UUID_SIZE);
 727
 728         if (!(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP)) {
 729                 ret = btrfs_read_chunk_tree(chunk_root);
 730                 BUG_ON(ret);
 731         }
 732
 733         blocksize = btrfs_level_size(tree_root,
 734                                      btrfs_super_root_level(disk_super));
 735         generation = btrfs_super_generation(disk_super);
 736
 737         tree_root->node = read_tree_block(tree_root,
 738                                           btrfs_super_root(disk_super),
 739                                           blocksize, generation);
 740         BUG_ON(!tree_root->node);
 741         ret = find_and_setup_root(tree_root, fs_info,
 742                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
 743         BUG_ON(ret);
 744         extent_root->track_dirty = 1;
 745
 746         ret = find_and_setup_root(tree_root, fs_info,
 747                                   BTRFS_DEV_TREE_OBJECTID, dev_root);
 748         BUG_ON(ret);
 749         dev_root->track_dirty = 1;
 750
 751         ret = find_and_setup_root(tree_root, fs_info,
 752                                   BTRFS_CSUM_TREE_OBJECTID, csum_root);
 753         BUG_ON(ret);
 754         csum_root->track_dirty = 1;
 755
 756         BUG_ON(ret);
 757
 758         find_and_setup_log_root(tree_root, fs_info, disk_super);
 759
 760         fs_info->generation = generation + 1;
 761         btrfs_read_block_groups(fs_info->tree_root);
 762
 763         key.objectid = BTRFS_FS_TREE_OBJECTID;
 764         key.type = BTRFS_ROOT_ITEM_KEY;
 765         key.offset = (u64)-1;
 766         fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
 767
 768         fs_info->data_alloc_profile = (u64)-1;
 769         fs_info->metadata_alloc_profile = (u64)-1;
 770         fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
 771
 772         return fs_info->fs_root;
 773 }
 774
 775 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr)
 776 {
 777         u8 fsid[BTRFS_FSID_SIZE];
 778         struct btrfs_super_block buf;
 779         int i;
 780         int ret;
 781         u64 transid = 0;
 782         u64 bytenr;
 783
 784         if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
 785                 ret = pread64(fd, &buf, sizeof(buf), sb_bytenr);
 786                 if (ret < sizeof(buf))
 787                         return -1;
 788
 789                 if (btrfs_super_bytenr(&buf) != sb_bytenr ||
 790                     strncmp((char *)(&buf.magic), BTRFS_MAGIC,
 791                             sizeof(buf.magic)))
 792                         return -1;
 793
 794                 memcpy(sb, &buf, sizeof(*sb));
 795                 return 0;
 796         }
 797
 798         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 799                 bytenr = btrfs_sb_offset(i);
 800                 ret = pread64(fd, &buf, sizeof(buf), bytenr);
 801                 if (ret < sizeof(buf))
 802                         break;
 803
 804                 if (btrfs_super_bytenr(&buf) != bytenr ||
 805                     strncmp((char *)(&buf.magic), BTRFS_MAGIC,
 806                             sizeof(buf.magic)))
 807                         continue;
 808
 809                 if (i == 0)
 810                         memcpy(fsid, buf.fsid, sizeof(fsid));
 811                 else if (memcmp(fsid, buf.fsid, sizeof(fsid)))
 812                         continue;
 813
 814                 if (btrfs_super_generation(&buf) > transid) {
 815                         memcpy(sb, &buf, sizeof(*sb));
 816                         transid = btrfs_super_generation(&buf);
 817                 }
 818         }
 819
 820         return transid > 0 ? 0 : -1;
 821 }
 822
 823 int write_dev_supers(struct btrfs_root *root, struct btrfs_super_block *sb,
 824                      struct btrfs_device *device)
 825 {
 826         u64 bytenr;
 827         u32 crc;
 828         int i, ret;
 829
 830         if (root->fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
 831                 btrfs_set_super_bytenr(sb, root->fs_info->super_bytenr);
 832
 833                 crc = ~(u32)0;
 834                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
 835                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 836                 btrfs_csum_final(crc, (char *)&sb->csum[0]);
 837
 838                 ret = pwrite64(device->fd, sb, BTRFS_SUPER_INFO_SIZE,
 839                                root->fs_info->super_bytenr);
 840                 BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
 841                 return 0;
 842         }
 843
 844         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 845                 bytenr = btrfs_sb_offset(i);
 846                 if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
 847                         break;
 848
 849                 btrfs_set_super_bytenr(sb, bytenr);
 850
 851                 crc = ~(u32)0;
 852                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
 853                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 854                 btrfs_csum_final(crc, (char *)&sb->csum[0]);
 855
 856                 ret = pwrite64(device->fd, sb, BTRFS_SUPER_INFO_SIZE, bytenr);
 857                 BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
 858         }
 859         return 0;
 860 }
 861
 862 int write_all_supers(struct btrfs_root *root)
 863 {
 864         struct list_head *cur;
 865         struct list_head *head = &root->fs_info->fs_devices->devices;
 866         struct btrfs_device *dev;
 867         struct btrfs_super_block *sb;
 868         struct btrfs_dev_item *dev_item;
 869         int ret;
 870         u64 flags;
 871
 872         sb = &root->fs_info->super_copy;
 873         dev_item = &sb->dev_item;
 874         list_for_each(cur, head) {
 875                 dev = list_entry(cur, struct btrfs_device, dev_list);
 876                 if (!dev->writeable)
 877                         continue;
 878
 879                 btrfs_set_stack_device_generation(dev_item, 0);
 880                 btrfs_set_stack_device_type(dev_item, dev->type);
 881                 btrfs_set_stack_device_id(dev_item, dev->devid);
 882                 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
 883                 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
 884                 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
 885                 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
 886                 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
 887                 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
 888                 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
 889
 890                 flags = btrfs_super_flags(sb);
 891                 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
 892
 893                 ret = write_dev_supers(root, sb, dev);
 894                 BUG_ON(ret);
 895         }
 896         return 0;
 897 }
 898
 899 int write_ctree_super(struct btrfs_trans_handle *trans,
 900                       struct btrfs_root *root)
 901 {
 902         int ret;
 903         struct btrfs_root *tree_root = root->fs_info->tree_root;
 904         struct btrfs_root *chunk_root = root->fs_info->chunk_root;
 905
 906         if (root->fs_info->readonly)
 907                 return 0;
 908
 909         btrfs_set_super_generation(&root->fs_info->super_copy,
 910                                    trans->transid);
 911         btrfs_set_super_root(&root->fs_info->super_copy,
 912                              tree_root->node->start);
 913         btrfs_set_super_root_level(&root->fs_info->super_copy,
 914                                    btrfs_header_level(tree_root->node));
 915         btrfs_set_super_chunk_root(&root->fs_info->super_copy,
 916                                    chunk_root->node->start);
 917         btrfs_set_super_chunk_root_level(&root->fs_info->super_copy,
 918                                          btrfs_header_level(chunk_root->node));
 919         btrfs_set_super_chunk_root_generation(&root->fs_info->super_copy,
 920                                 btrfs_header_generation(chunk_root->node));
 921
 922         ret = write_all_supers(root);
 923         if (ret)
 924                 fprintf(stderr, "failed to write new super block err %d\n", ret);
 925         return ret;
 926 }
 927
 928 static int close_all_devices(struct btrfs_fs_info *fs_info)
 929 {
 930         struct list_head *list;
 931         struct list_head *next;
 932         struct btrfs_device *device;
 933
 934         return 0;
 935
 936         list = &fs_info->fs_devices->devices;
 937         list_for_each(next, list) {
 938                 device = list_entry(next, struct btrfs_device, dev_list);
 939                 close(device->fd);
 940         }
 941         return 0;
 942 }
 943
 944 int close_ctree(struct btrfs_root *root)
 945 {
 946         int ret;
 947         struct btrfs_trans_handle *trans;
 948         struct btrfs_fs_info *fs_info = root->fs_info;
 949
 950         trans = btrfs_start_transaction(root, 1);
 951         btrfs_commit_transaction(trans, root);
 952         trans = btrfs_start_transaction(root, 1);
 953         ret = commit_tree_roots(trans, fs_info);
 954         BUG_ON(ret);
 955         ret = __commit_transaction(trans, root);
 956         BUG_ON(ret);
 957         write_ctree_super(trans, root);
 958         btrfs_free_transaction(root, trans);
 959         btrfs_free_block_groups(fs_info);
 960
 961         free_fs_roots(fs_info);
 962
 963         if (fs_info->extent_root->node)
 964                 free_extent_buffer(fs_info->extent_root->node);
 965         if (fs_info->tree_root->node)
 966                 free_extent_buffer(fs_info->tree_root->node);
 967         if (fs_info->chunk_root->node)
 968                 free_extent_buffer(fs_info->chunk_root->node);
 969         if (fs_info->dev_root->node)
 970                 free_extent_buffer(fs_info->dev_root->node);
 971         if (fs_info->csum_root->node)
 972                 free_extent_buffer(fs_info->csum_root->node);
 973
 974         if (fs_info->log_root_tree) {
 975                 if (fs_info->log_root_tree->node)
 976                         free_extent_buffer(fs_info->log_root_tree->node);
 977                 free(fs_info->log_root_tree);
 978         }
 979
 980         close_all_devices(fs_info);
 981         extent_io_tree_cleanup(&fs_info->extent_cache);
 982         extent_io_tree_cleanup(&fs_info->free_space_cache);
 983         extent_io_tree_cleanup(&fs_info->block_group_cache);
 984         extent_io_tree_cleanup(&fs_info->pinned_extents);
 985         extent_io_tree_cleanup(&fs_info->pending_del);
 986         extent_io_tree_cleanup(&fs_info->extent_ins);
 987
 988         free(fs_info->tree_root);
 989         free(fs_info->extent_root);
 990         free(fs_info->chunk_root);
 991         free(fs_info->dev_root);
 992         free(fs_info->csum_root);
 993         free(fs_info);
 994
 995         return 0;
 996 }
 997
 998 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 999                      struct extent_buffer *eb)
1000 {
1001         return clear_extent_buffer_dirty(eb);
1002 }
1003
1004 int wait_on_tree_block_writeback(struct btrfs_root *root,
1005                                  struct extent_buffer *eb)
1006 {
1007         return 0;
1008 }
1009
1010 void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
1011 {
1012         set_extent_buffer_dirty(eb);
1013 }
1014
1015 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1016 {
1017         int ret;
1018
1019         ret = extent_buffer_uptodate(buf);
1020         if (!ret)
1021                 return ret;
1022
1023         ret = verify_parent_transid(buf->tree, buf, parent_transid);
1024         return !ret;
1025 }
1026
1027 int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
1028 {
1029         return set_extent_buffer_uptodate(eb);
1030 }