fs/btrfs/disk-io.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2007 Oracle.  All rights reserved.
   4  */
   5
   6 #include <linux/fs.h>
   7 #include <linux/blkdev.h>
   8 #include <linux/writeback.h>
   9 #include <linux/workqueue.h>
  10 #include <linux/kthread.h>
  11 #include <linux/slab.h>
  12 #include <linux/migrate.h>
  13 #include <linux/ratelimit.h>
  14 #include <linux/uuid.h>
  15 #include <linux/semaphore.h>
  16 #include <linux/error-injection.h>
  17 #include <linux/crc32c.h>
  18 #include <linux/sched/mm.h>
  19 #include <asm/unaligned.h>
  20 #include <crypto/hash.h>
  21 #include "ctree.h"
  22 #include "disk-io.h"
  23 #include "transaction.h"
  24 #include "btrfs_inode.h"
  25 #include "volumes.h"
  26 #include "print-tree.h"
  27 #include "locking.h"
  28 #include "tree-log.h"
  29 #include "free-space-cache.h"
  30 #include "free-space-tree.h"
  31 #include "check-integrity.h"
  32 #include "rcu-string.h"
  33 #include "dev-replace.h"
  34 #include "raid56.h"
  35 #include "sysfs.h"
  36 #include "qgroup.h"
  37 #include "compression.h"
  38 #include "tree-checker.h"
  39 #include "ref-verify.h"
  40 #include "block-group.h"
  41 #include "discard.h"
  42 #include "space-info.h"
  43 #include "zoned.h"
  44 #include "subpage.h"
  45
  46 #define BTRFS_SUPER_FLAG_SUPP   (BTRFS_HEADER_FLAG_WRITTEN |\
  47                                  BTRFS_HEADER_FLAG_RELOC |\
  48                                  BTRFS_SUPER_FLAG_ERROR |\
  49                                  BTRFS_SUPER_FLAG_SEEDING |\
  50                                  BTRFS_SUPER_FLAG_METADUMP |\
  51                                  BTRFS_SUPER_FLAG_METADUMP_V2)
  52
  53 static void end_workqueue_fn(struct btrfs_work *work);
  54 static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  55 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  56                                       struct btrfs_fs_info *fs_info);
  57 static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  58 static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
  59                                         struct extent_io_tree *dirty_pages,
  60                                         int mark);
  61 static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
  62                                        struct extent_io_tree *pinned_extents);
  63 static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  64 static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  65
  66 /*
  67  * btrfs_end_io_wq structs are used to do processing in task context when an IO
  68  * is complete.  This is used during reads to verify checksums, and it is used
  69  * by writes to insert metadata for new file extents after IO is complete.
  70  */
  71 struct btrfs_end_io_wq {
  72         struct bio *bio;
  73         bio_end_io_t *end_io;
  74         void *private;
  75         struct btrfs_fs_info *info;
  76         blk_status_t status;
  77         enum btrfs_wq_endio_type metadata;
  78         struct btrfs_work work;
  79 };
  80
  81 static struct kmem_cache *btrfs_end_io_wq_cache;
  82
  83 int __init btrfs_end_io_wq_init(void)
  84 {
  85         btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
  86                                         sizeof(struct btrfs_end_io_wq),
  87                                         0,
  88                                         SLAB_MEM_SPREAD,
  89                                         NULL);
  90         if (!btrfs_end_io_wq_cache)
  91                 return -ENOMEM;
  92         return 0;
  93 }
  94
  95 void __cold btrfs_end_io_wq_exit(void)
  96 {
  97         kmem_cache_destroy(btrfs_end_io_wq_cache);
  98 }
  99
 100 static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
 101 {
 102         if (fs_info->csum_shash)
 103                 crypto_free_shash(fs_info->csum_shash);
 104 }
 105
 106 /*
 107  * async submit bios are used to offload expensive checksumming
 108  * onto the worker threads.  They checksum file and metadata bios
 109  * just before they are sent down the IO stack.
 110  */
 111 struct async_submit_bio {
 112         struct inode *inode;
 113         struct bio *bio;
 114         extent_submit_bio_start_t *submit_bio_start;
 115         int mirror_num;
 116
 117         /* Optional parameter for submit_bio_start used by direct io */
 118         u64 dio_file_offset;
 119         struct btrfs_work work;
 120         blk_status_t status;
 121 };
 122
 123 /*
 124  * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 125  * eb, the lockdep key is determined by the btrfs_root it belongs to and
 126  * the level the eb occupies in the tree.
 127  *
 128  * Different roots are used for different purposes and may nest inside each
 129  * other and they require separate keysets.  As lockdep keys should be
 130  * static, assign keysets according to the purpose of the root as indicated
 131  * by btrfs_root->root_key.objectid.  This ensures that all special purpose
 132  * roots have separate keysets.
 133  *
 134  * Lock-nesting across peer nodes is always done with the immediate parent
 135  * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 136  * subclass to avoid triggering lockdep warning in such cases.
 137  *
 138  * The key is set by the readpage_end_io_hook after the buffer has passed
 139  * csum validation but before the pages are unlocked.  It is also set by
 140  * btrfs_init_new_buffer on freshly allocated blocks.
 141  *
 142  * We also add a check to make sure the highest level of the tree is the
 143  * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 144  * needs update as well.
 145  */
 146 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 147 # if BTRFS_MAX_LEVEL != 8
 148 #  error
 149 # endif
 150
 151 #define DEFINE_LEVEL(stem, level)                                       \
 152         .names[level] = "btrfs-" stem "-0" #level,
 153
 154 #define DEFINE_NAME(stem)                                               \
 155         DEFINE_LEVEL(stem, 0)                                           \
 156         DEFINE_LEVEL(stem, 1)                                           \
 157         DEFINE_LEVEL(stem, 2)                                           \
 158         DEFINE_LEVEL(stem, 3)                                           \
 159         DEFINE_LEVEL(stem, 4)                                           \
 160         DEFINE_LEVEL(stem, 5)                                           \
 161         DEFINE_LEVEL(stem, 6)                                           \
 162         DEFINE_LEVEL(stem, 7)
 163
 164 static struct btrfs_lockdep_keyset {
 165         u64                     id;             /* root objectid */
 166         /* Longest entry: btrfs-free-space-00 */
 167         char                    names[BTRFS_MAX_LEVEL][20];
 168         struct lock_class_key   keys[BTRFS_MAX_LEVEL];
 169 } btrfs_lockdep_keysets[] = {
 170         { .id = BTRFS_ROOT_TREE_OBJECTID,       DEFINE_NAME("root")     },
 171         { .id = BTRFS_EXTENT_TREE_OBJECTID,     DEFINE_NAME("extent")   },
 172         { .id = BTRFS_CHUNK_TREE_OBJECTID,      DEFINE_NAME("chunk")    },
 173         { .id = BTRFS_DEV_TREE_OBJECTID,        DEFINE_NAME("dev")      },
 174         { .id = BTRFS_CSUM_TREE_OBJECTID,       DEFINE_NAME("csum")     },
 175         { .id = BTRFS_QUOTA_TREE_OBJECTID,      DEFINE_NAME("quota")    },
 176         { .id = BTRFS_TREE_LOG_OBJECTID,        DEFINE_NAME("log")      },
 177         { .id = BTRFS_TREE_RELOC_OBJECTID,      DEFINE_NAME("treloc")   },
 178         { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, DEFINE_NAME("dreloc")   },
 179         { .id = BTRFS_UUID_TREE_OBJECTID,       DEFINE_NAME("uuid")     },
 180         { .id = BTRFS_FREE_SPACE_TREE_OBJECTID, DEFINE_NAME("free-space") },
 181         { .id = 0,                              DEFINE_NAME("tree")     },
 182 };
 183
 184 #undef DEFINE_LEVEL
 185 #undef DEFINE_NAME
 186
 187 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 188                                     int level)
 189 {
 190         struct btrfs_lockdep_keyset *ks;
 191
 192         BUG_ON(level >= ARRAY_SIZE(ks->keys));
 193
 194         /* find the matching keyset, id 0 is the default entry */
 195         for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 196                 if (ks->id == objectid)
 197                         break;
 198
 199         lockdep_set_class_and_name(&eb->lock,
 200                                    &ks->keys[level], ks->names[level]);
 201 }
 202
 203 #endif
 204
 205 /*
 206  * Compute the csum of a btree block and store the result to provided buffer.
 207  */
 208 static void csum_tree_block(struct extent_buffer *buf, u8 *result)
 209 {
 210         struct btrfs_fs_info *fs_info = buf->fs_info;
 211         const int num_pages = num_extent_pages(buf);
 212         const int first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
 213         SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 214         char *kaddr;
 215         int i;
 216
 217         shash->tfm = fs_info->csum_shash;
 218         crypto_shash_init(shash);
 219         kaddr = page_address(buf->pages[0]) + offset_in_page(buf->start);
 220         crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
 221                             first_page_part - BTRFS_CSUM_SIZE);
 222
 223         for (i = 1; i < num_pages; i++) {
 224                 kaddr = page_address(buf->pages[i]);
 225                 crypto_shash_update(shash, kaddr, PAGE_SIZE);
 226         }
 227         memset(result, 0, BTRFS_CSUM_SIZE);
 228         crypto_shash_final(shash, result);
 229 }
 230
 231 /*
 232  * we can't consider a given block up to date unless the transid of the
 233  * block matches the transid in the parent node's pointer.  This is how we
 234  * detect blocks that either didn't get written at all or got written
 235  * in the wrong place.
 236  */
 237 static int verify_parent_transid(struct extent_io_tree *io_tree,
 238                                  struct extent_buffer *eb, u64 parent_transid,
 239                                  int atomic)
 240 {
 241         struct extent_state *cached_state = NULL;
 242         int ret;
 243
 244         if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 245                 return 0;
 246
 247         if (atomic)
 248                 return -EAGAIN;
 249
 250         lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 251                          &cached_state);
 252         if (extent_buffer_uptodate(eb) &&
 253             btrfs_header_generation(eb) == parent_transid) {
 254                 ret = 0;
 255                 goto out;
 256         }
 257         btrfs_err_rl(eb->fs_info,
 258                 "parent transid verify failed on %llu wanted %llu found %llu",
 259                         eb->start,
 260                         parent_transid, btrfs_header_generation(eb));
 261         ret = 1;
 262         clear_extent_buffer_uptodate(eb);
 263 out:
 264         unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 265                              &cached_state);
 266         return ret;
 267 }
 268
 269 static bool btrfs_supported_super_csum(u16 csum_type)
 270 {
 271         switch (csum_type) {
 272         case BTRFS_CSUM_TYPE_CRC32:
 273         case BTRFS_CSUM_TYPE_XXHASH:
 274         case BTRFS_CSUM_TYPE_SHA256:
 275         case BTRFS_CSUM_TYPE_BLAKE2:
 276                 return true;
 277         default:
 278                 return false;
 279         }
 280 }
 281
 282 /*
 283  * Return 0 if the superblock checksum type matches the checksum value of that
 284  * algorithm. Pass the raw disk superblock data.
 285  */
 286 static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 287                                   char *raw_disk_sb)
 288 {
 289         struct btrfs_super_block *disk_sb =
 290                 (struct btrfs_super_block *)raw_disk_sb;
 291         char result[BTRFS_CSUM_SIZE];
 292         SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 293
 294         shash->tfm = fs_info->csum_shash;
 295
 296         /*
 297          * The super_block structure does not span the whole
 298          * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
 299          * filled with zeros and is included in the checksum.
 300          */
 301         crypto_shash_digest(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
 302                             BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
 303
 304         if (memcmp(disk_sb->csum, result, fs_info->csum_size))
 305                 return 1;
 306
 307         return 0;
 308 }
 309
 310 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
 311                            struct btrfs_key *first_key, u64 parent_transid)
 312 {
 313         struct btrfs_fs_info *fs_info = eb->fs_info;
 314         int found_level;
 315         struct btrfs_key found_key;
 316         int ret;
 317
 318         found_level = btrfs_header_level(eb);
 319         if (found_level != level) {
 320                 WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 321                      KERN_ERR "BTRFS: tree level check failed\n");
 322                 btrfs_err(fs_info,
 323 "tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
 324                           eb->start, level, found_level);
 325                 return -EIO;
 326         }
 327
 328         if (!first_key)
 329                 return 0;
 330
 331         /*
 332          * For live tree block (new tree blocks in current transaction),
 333          * we need proper lock context to avoid race, which is impossible here.
 334          * So we only checks tree blocks which is read from disk, whose
 335          * generation <= fs_info->last_trans_committed.
 336          */
 337         if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
 338                 return 0;
 339
 340         /* We have @first_key, so this @eb must have at least one item */
 341         if (btrfs_header_nritems(eb) == 0) {
 342                 btrfs_err(fs_info,
 343                 "invalid tree nritems, bytenr=%llu nritems=0 expect >0",
 344                           eb->start);
 345                 WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 346                 return -EUCLEAN;
 347         }
 348
 349         if (found_level)
 350                 btrfs_node_key_to_cpu(eb, &found_key, 0);
 351         else
 352                 btrfs_item_key_to_cpu(eb, &found_key, 0);
 353         ret = btrfs_comp_cpu_keys(first_key, &found_key);
 354
 355         if (ret) {
 356                 WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 357                      KERN_ERR "BTRFS: tree first key check failed\n");
 358                 btrfs_err(fs_info,
 359 "tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 360                           eb->start, parent_transid, first_key->objectid,
 361                           first_key->type, first_key->offset,
 362                           found_key.objectid, found_key.type,
 363                           found_key.offset);
 364         }
 365         return ret;
 366 }
 367
 368 /*
 369  * helper to read a given tree block, doing retries as required when
 370  * the checksums don't match and we have alternate mirrors to try.
 371  *
 372  * @parent_transid:     expected transid, skip check if 0
 373  * @level:              expected level, mandatory check
 374  * @first_key:          expected key of first slot, skip check if NULL
 375  */
 376 int btrfs_read_extent_buffer(struct extent_buffer *eb,
 377                              u64 parent_transid, int level,
 378                              struct btrfs_key *first_key)
 379 {
 380         struct btrfs_fs_info *fs_info = eb->fs_info;
 381         struct extent_io_tree *io_tree;
 382         int failed = 0;
 383         int ret;
 384         int num_copies = 0;
 385         int mirror_num = 0;
 386         int failed_mirror = 0;
 387
 388         io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
 389         while (1) {
 390                 clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 391                 ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num);
 392                 if (!ret) {
 393                         if (verify_parent_transid(io_tree, eb,
 394                                                    parent_transid, 0))
 395                                 ret = -EIO;
 396                         else if (btrfs_verify_level_key(eb, level,
 397                                                 first_key, parent_transid))
 398                                 ret = -EUCLEAN;
 399                         else
 400                                 break;
 401                 }
 402
 403                 num_copies = btrfs_num_copies(fs_info,
 404                                               eb->start, eb->len);
 405                 if (num_copies == 1)
 406                         break;
 407
 408                 if (!failed_mirror) {
 409                         failed = 1;
 410                         failed_mirror = eb->read_mirror;
 411                 }
 412
 413                 mirror_num++;
 414                 if (mirror_num == failed_mirror)
 415                         mirror_num++;
 416
 417                 if (mirror_num > num_copies)
 418                         break;
 419         }
 420
 421         if (failed && !ret && failed_mirror)
 422                 btrfs_repair_eb_io_failure(eb, failed_mirror);
 423
 424         return ret;
 425 }
 426
 427 static int csum_one_extent_buffer(struct extent_buffer *eb)
 428 {
 429         struct btrfs_fs_info *fs_info = eb->fs_info;
 430         u8 result[BTRFS_CSUM_SIZE];
 431         int ret;
 432
 433         ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 434                                     offsetof(struct btrfs_header, fsid),
 435                                     BTRFS_FSID_SIZE) == 0);
 436         csum_tree_block(eb, result);
 437
 438         if (btrfs_header_level(eb))
 439                 ret = btrfs_check_node(eb);
 440         else
 441                 ret = btrfs_check_leaf_full(eb);
 442
 443         if (ret < 0)
 444                 goto error;
 445
 446         /*
 447          * Also check the generation, the eb reached here must be newer than
 448          * last committed. Or something seriously wrong happened.
 449          */
 450         if (unlikely(btrfs_header_generation(eb) <= fs_info->last_trans_committed)) {
 451                 ret = -EUCLEAN;
 452                 btrfs_err(fs_info,
 453                         "block=%llu bad generation, have %llu expect > %llu",
 454                           eb->start, btrfs_header_generation(eb),
 455                           fs_info->last_trans_committed);
 456                 goto error;
 457         }
 458         write_extent_buffer(eb, result, 0, fs_info->csum_size);
 459
 460         return 0;
 461
 462 error:
 463         btrfs_print_tree(eb, 0);
 464         btrfs_err(fs_info, "block=%llu write time tree block corruption detected",
 465                   eb->start);
 466         WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 467         return ret;
 468 }
 469
 470 /* Checksum all dirty extent buffers in one bio_vec */
 471 static int csum_dirty_subpage_buffers(struct btrfs_fs_info *fs_info,
 472                                       struct bio_vec *bvec)
 473 {
 474         struct page *page = bvec->bv_page;
 475         u64 bvec_start = page_offset(page) + bvec->bv_offset;
 476         u64 cur;
 477         int ret = 0;
 478
 479         for (cur = bvec_start; cur < bvec_start + bvec->bv_len;
 480              cur += fs_info->nodesize) {
 481                 struct extent_buffer *eb;
 482                 bool uptodate;
 483
 484                 eb = find_extent_buffer(fs_info, cur);
 485                 uptodate = btrfs_subpage_test_uptodate(fs_info, page, cur,
 486                                                        fs_info->nodesize);
 487
 488                 /* A dirty eb shouldn't disappear from extent_buffers */
 489                 if (WARN_ON(!eb))
 490                         return -EUCLEAN;
 491
 492                 if (WARN_ON(cur != btrfs_header_bytenr(eb))) {
 493                         free_extent_buffer(eb);
 494                         return -EUCLEAN;
 495                 }
 496                 if (WARN_ON(!uptodate)) {
 497                         free_extent_buffer(eb);
 498                         return -EUCLEAN;
 499                 }
 500
 501                 ret = csum_one_extent_buffer(eb);
 502                 free_extent_buffer(eb);
 503                 if (ret < 0)
 504                         return ret;
 505         }
 506         return ret;
 507 }
 508
 509 /*
 510  * Checksum a dirty tree block before IO.  This has extra checks to make sure
 511  * we only fill in the checksum field in the first page of a multi-page block.
 512  * For subpage extent buffers we need bvec to also read the offset in the page.
 513  */
 514 static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct bio_vec *bvec)
 515 {
 516         struct page *page = bvec->bv_page;
 517         u64 start = page_offset(page);
 518         u64 found_start;
 519         struct extent_buffer *eb;
 520
 521         if (fs_info->nodesize < PAGE_SIZE)
 522                 return csum_dirty_subpage_buffers(fs_info, bvec);
 523
 524         eb = (struct extent_buffer *)page->private;
 525         if (page != eb->pages[0])
 526                 return 0;
 527
 528         found_start = btrfs_header_bytenr(eb);
 529
 530         if (test_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags)) {
 531                 WARN_ON(found_start != 0);
 532                 return 0;
 533         }
 534
 535         /*
 536          * Please do not consolidate these warnings into a single if.
 537          * It is useful to know what went wrong.
 538          */
 539         if (WARN_ON(found_start != start))
 540                 return -EUCLEAN;
 541         if (WARN_ON(!PageUptodate(page)))
 542                 return -EUCLEAN;
 543
 544         return csum_one_extent_buffer(eb);
 545 }
 546
 547 static int check_tree_block_fsid(struct extent_buffer *eb)
 548 {
 549         struct btrfs_fs_info *fs_info = eb->fs_info;
 550         struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
 551         u8 fsid[BTRFS_FSID_SIZE];
 552         u8 *metadata_uuid;
 553
 554         read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
 555                            BTRFS_FSID_SIZE);
 556         /*
 557          * Checking the incompat flag is only valid for the current fs. For
 558          * seed devices it's forbidden to have their uuid changed so reading
 559          * ->fsid in this case is fine
 560          */
 561         if (btrfs_fs_incompat(fs_info, METADATA_UUID))
 562                 metadata_uuid = fs_devices->metadata_uuid;
 563         else
 564                 metadata_uuid = fs_devices->fsid;
 565
 566         if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))
 567                 return 0;
 568
 569         list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
 570                 if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
 571                         return 0;
 572
 573         return 1;
 574 }
 575
 576 /* Do basic extent buffer checks at read time */
 577 static int validate_extent_buffer(struct extent_buffer *eb)
 578 {
 579         struct btrfs_fs_info *fs_info = eb->fs_info;
 580         u64 found_start;
 581         const u32 csum_size = fs_info->csum_size;
 582         u8 found_level;
 583         u8 result[BTRFS_CSUM_SIZE];
 584         const u8 *header_csum;
 585         int ret = 0;
 586
 587         found_start = btrfs_header_bytenr(eb);
 588         if (found_start != eb->start) {
 589                 btrfs_err_rl(fs_info, "bad tree block start, want %llu have %llu",
 590                              eb->start, found_start);
 591                 ret = -EIO;
 592                 goto out;
 593         }
 594         if (check_tree_block_fsid(eb)) {
 595                 btrfs_err_rl(fs_info, "bad fsid on block %llu",
 596                              eb->start);
 597                 ret = -EIO;
 598                 goto out;
 599         }
 600         found_level = btrfs_header_level(eb);
 601         if (found_level >= BTRFS_MAX_LEVEL) {
 602                 btrfs_err(fs_info, "bad tree block level %d on %llu",
 603                           (int)btrfs_header_level(eb), eb->start);
 604                 ret = -EIO;
 605                 goto out;
 606         }
 607
 608         csum_tree_block(eb, result);
 609         header_csum = page_address(eb->pages[0]) +
 610                 get_eb_offset_in_page(eb, offsetof(struct btrfs_header, csum));
 611
 612         if (memcmp(result, header_csum, csum_size) != 0) {
 613                 btrfs_warn_rl(fs_info,
 614         "checksum verify failed on %llu wanted " CSUM_FMT " found " CSUM_FMT " level %d",
 615                               eb->start,
 616                               CSUM_FMT_VALUE(csum_size, header_csum),
 617                               CSUM_FMT_VALUE(csum_size, result),
 618                               btrfs_header_level(eb));
 619                 ret = -EUCLEAN;
 620                 goto out;
 621         }
 622
 623         /*
 624          * If this is a leaf block and it is corrupt, set the corrupt bit so
 625          * that we don't try and read the other copies of this block, just
 626          * return -EIO.
 627          */
 628         if (found_level == 0 && btrfs_check_leaf_full(eb)) {
 629                 set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 630                 ret = -EIO;
 631         }
 632
 633         if (found_level > 0 && btrfs_check_node(eb))
 634                 ret = -EIO;
 635
 636         if (!ret)
 637                 set_extent_buffer_uptodate(eb);
 638         else
 639                 btrfs_err(fs_info,
 640                           "block=%llu read time tree block corruption detected",
 641                           eb->start);
 642 out:
 643         return ret;
 644 }
 645
 646 static int validate_subpage_buffer(struct page *page, u64 start, u64 end,
 647                                    int mirror)
 648 {
 649         struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb);
 650         struct extent_buffer *eb;
 651         bool reads_done;
 652         int ret = 0;
 653
 654         /*
 655          * We don't allow bio merge for subpage metadata read, so we should
 656          * only get one eb for each endio hook.
 657          */
 658         ASSERT(end == start + fs_info->nodesize - 1);
 659         ASSERT(PagePrivate(page));
 660
 661         eb = find_extent_buffer(fs_info, start);
 662         /*
 663          * When we are reading one tree block, eb must have been inserted into
 664          * the radix tree. If not, something is wrong.
 665          */
 666         ASSERT(eb);
 667
 668         reads_done = atomic_dec_and_test(&eb->io_pages);
 669         /* Subpage read must finish in page read */
 670         ASSERT(reads_done);
 671
 672         eb->read_mirror = mirror;
 673         if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 674                 ret = -EIO;
 675                 goto err;
 676         }
 677         ret = validate_extent_buffer(eb);
 678         if (ret < 0)
 679                 goto err;
 680
 681         set_extent_buffer_uptodate(eb);
 682
 683         free_extent_buffer(eb);
 684         return ret;
 685 err:
 686         /*
 687          * end_bio_extent_readpage decrements io_pages in case of error,
 688          * make sure it has something to decrement.
 689          */
 690         atomic_inc(&eb->io_pages);
 691         clear_extent_buffer_uptodate(eb);
 692         free_extent_buffer(eb);
 693         return ret;
 694 }
 695
 696 int btrfs_validate_metadata_buffer(struct btrfs_bio *bbio,
 697                                    struct page *page, u64 start, u64 end,
 698                                    int mirror)
 699 {
 700         struct extent_buffer *eb;
 701         int ret = 0;
 702         int reads_done;
 703
 704         ASSERT(page->private);
 705
 706         if (btrfs_sb(page->mapping->host->i_sb)->nodesize < PAGE_SIZE)
 707                 return validate_subpage_buffer(page, start, end, mirror);
 708
 709         eb = (struct extent_buffer *)page->private;
 710
 711         /*
 712          * The pending IO might have been the only thing that kept this buffer
 713          * in memory.  Make sure we have a ref for all this other checks
 714          */
 715         atomic_inc(&eb->refs);
 716
 717         reads_done = atomic_dec_and_test(&eb->io_pages);
 718         if (!reads_done)
 719                 goto err;
 720
 721         eb->read_mirror = mirror;
 722         if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 723                 ret = -EIO;
 724                 goto err;
 725         }
 726         ret = validate_extent_buffer(eb);
 727 err:
 728         if (ret) {
 729                 /*
 730                  * our io error hook is going to dec the io pages
 731                  * again, we have to make sure it has something
 732                  * to decrement
 733                  */
 734                 atomic_inc(&eb->io_pages);
 735                 clear_extent_buffer_uptodate(eb);
 736         }
 737         free_extent_buffer(eb);
 738
 739         return ret;
 740 }
 741
 742 static void end_workqueue_bio(struct bio *bio)
 743 {
 744         struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
 745         struct btrfs_fs_info *fs_info;
 746         struct btrfs_workqueue *wq;
 747
 748         fs_info = end_io_wq->info;
 749         end_io_wq->status = bio->bi_status;
 750
 751         if (btrfs_op(bio) == BTRFS_MAP_WRITE) {
 752                 if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA)
 753                         wq = fs_info->endio_meta_write_workers;
 754                 else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE)
 755                         wq = fs_info->endio_freespace_worker;
 756                 else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
 757                         wq = fs_info->endio_raid56_workers;
 758                 else
 759                         wq = fs_info->endio_write_workers;
 760         } else {
 761                 if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
 762                         wq = fs_info->endio_raid56_workers;
 763                 else if (end_io_wq->metadata)
 764                         wq = fs_info->endio_meta_workers;
 765                 else
 766                         wq = fs_info->endio_workers;
 767         }
 768
 769         btrfs_init_work(&end_io_wq->work, end_workqueue_fn, NULL, NULL);
 770         btrfs_queue_work(wq, &end_io_wq->work);
 771 }
 772
 773 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 774                         enum btrfs_wq_endio_type metadata)
 775 {
 776         struct btrfs_end_io_wq *end_io_wq;
 777
 778         end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
 779         if (!end_io_wq)
 780                 return BLK_STS_RESOURCE;
 781
 782         end_io_wq->private = bio->bi_private;
 783         end_io_wq->end_io = bio->bi_end_io;
 784         end_io_wq->info = info;
 785         end_io_wq->status = 0;
 786         end_io_wq->bio = bio;
 787         end_io_wq->metadata = metadata;
 788
 789         bio->bi_private = end_io_wq;
 790         bio->bi_end_io = end_workqueue_bio;
 791         return 0;
 792 }
 793
 794 static void run_one_async_start(struct btrfs_work *work)
 795 {
 796         struct async_submit_bio *async;
 797         blk_status_t ret;
 798
 799         async = container_of(work, struct  async_submit_bio, work);
 800         ret = async->submit_bio_start(async->inode, async->bio,
 801                                       async->dio_file_offset);
 802         if (ret)
 803                 async->status = ret;
 804 }
 805
 806 /*
 807  * In order to insert checksums into the metadata in large chunks, we wait
 808  * until bio submission time.   All the pages in the bio are checksummed and
 809  * sums are attached onto the ordered extent record.
 810  *
 811  * At IO completion time the csums attached on the ordered extent record are
 812  * inserted into the tree.
 813  */
 814 static void run_one_async_done(struct btrfs_work *work)
 815 {
 816         struct async_submit_bio *async;
 817         struct inode *inode;
 818         blk_status_t ret;
 819
 820         async = container_of(work, struct  async_submit_bio, work);
 821         inode = async->inode;
 822
 823         /* If an error occurred we just want to clean up the bio and move on */
 824         if (async->status) {
 825                 async->bio->bi_status = async->status;
 826                 bio_endio(async->bio);
 827                 return;
 828         }
 829
 830         /*
 831          * All of the bios that pass through here are from async helpers.
 832          * Use REQ_CGROUP_PUNT to issue them from the owning cgroup's context.
 833          * This changes nothing when cgroups aren't in use.
 834          */
 835         async->bio->bi_opf |= REQ_CGROUP_PUNT;
 836         ret = btrfs_map_bio(btrfs_sb(inode->i_sb), async->bio, async->mirror_num);
 837         if (ret) {
 838                 async->bio->bi_status = ret;
 839                 bio_endio(async->bio);
 840         }
 841 }
 842
 843 static void run_one_async_free(struct btrfs_work *work)
 844 {
 845         struct async_submit_bio *async;
 846
 847         async = container_of(work, struct  async_submit_bio, work);
 848         kfree(async);
 849 }
 850
 851 blk_status_t btrfs_wq_submit_bio(struct inode *inode, struct bio *bio,
 852                                  int mirror_num, u64 dio_file_offset,
 853                                  extent_submit_bio_start_t *submit_bio_start)
 854 {
 855         struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
 856         struct async_submit_bio *async;
 857
 858         async = kmalloc(sizeof(*async), GFP_NOFS);
 859         if (!async)
 860                 return BLK_STS_RESOURCE;
 861
 862         async->inode = inode;
 863         async->bio = bio;
 864         async->mirror_num = mirror_num;
 865         async->submit_bio_start = submit_bio_start;
 866
 867         btrfs_init_work(&async->work, run_one_async_start, run_one_async_done,
 868                         run_one_async_free);
 869
 870         async->dio_file_offset = dio_file_offset;
 871
 872         async->status = 0;
 873
 874         if (op_is_sync(bio->bi_opf))
 875                 btrfs_queue_work(fs_info->hipri_workers, &async->work);
 876         else
 877                 btrfs_queue_work(fs_info->workers, &async->work);
 878         return 0;
 879 }
 880
 881 static blk_status_t btree_csum_one_bio(struct bio *bio)
 882 {
 883         struct bio_vec *bvec;
 884         struct btrfs_root *root;
 885         int ret = 0;
 886         struct bvec_iter_all iter_all;
 887
 888         ASSERT(!bio_flagged(bio, BIO_CLONED));
 889         bio_for_each_segment_all(bvec, bio, iter_all) {
 890                 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 891                 ret = csum_dirty_buffer(root->fs_info, bvec);
 892                 if (ret)
 893                         break;
 894         }
 895
 896         return errno_to_blk_status(ret);
 897 }
 898
 899 static blk_status_t btree_submit_bio_start(struct inode *inode, struct bio *bio,
 900                                            u64 dio_file_offset)
 901 {
 902         /*
 903          * when we're called for a write, we're already in the async
 904          * submission context.  Just jump into btrfs_map_bio
 905          */
 906         return btree_csum_one_bio(bio);
 907 }
 908
 909 static bool should_async_write(struct btrfs_fs_info *fs_info,
 910                              struct btrfs_inode *bi)
 911 {
 912         if (btrfs_is_zoned(fs_info))
 913                 return false;
 914         if (atomic_read(&bi->sync_writers))
 915                 return false;
 916         if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 917                 return false;
 918         return true;
 919 }
 920
 921 void btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio, int mirror_num)
 922 {
 923         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 924         blk_status_t ret;
 925
 926         if (btrfs_op(bio) != BTRFS_MAP_WRITE) {
 927                 /*
 928                  * called for a read, do the setup so that checksum validation
 929                  * can happen in the async kernel threads
 930                  */
 931                 ret = btrfs_bio_wq_end_io(fs_info, bio,
 932                                           BTRFS_WQ_ENDIO_METADATA);
 933                 if (!ret)
 934                         ret = btrfs_map_bio(fs_info, bio, mirror_num);
 935         } else if (!should_async_write(fs_info, BTRFS_I(inode))) {
 936                 ret = btree_csum_one_bio(bio);
 937                 if (!ret)
 938                         ret = btrfs_map_bio(fs_info, bio, mirror_num);
 939         } else {
 940                 /*
 941                  * kthread helpers are used to submit writes so that
 942                  * checksumming can happen in parallel across all CPUs
 943                  */
 944                 ret = btrfs_wq_submit_bio(inode, bio, mirror_num, 0,
 945                                           btree_submit_bio_start);
 946         }
 947
 948         if (ret) {
 949                 bio->bi_status = ret;
 950                 bio_endio(bio);
 951         }
 952 }
 953
 954 #ifdef CONFIG_MIGRATION
 955 static int btree_migratepage(struct address_space *mapping,
 956                         struct page *newpage, struct page *page,
 957                         enum migrate_mode mode)
 958 {
 959         /*
 960          * we can't safely write a btree page from here,
 961          * we haven't done the locking hook
 962          */
 963         if (PageDirty(page))
 964                 return -EAGAIN;
 965         /*
 966          * Buffers may be managed in a filesystem specific way.
 967          * We must have no buffers or drop them.
 968          */
 969         if (page_has_private(page) &&
 970             !try_to_release_page(page, GFP_KERNEL))
 971                 return -EAGAIN;
 972         return migrate_page(mapping, newpage, page, mode);
 973 }
 974 #endif
 975
 976
 977 static int btree_writepages(struct address_space *mapping,
 978                             struct writeback_control *wbc)
 979 {
 980         struct btrfs_fs_info *fs_info;
 981         int ret;
 982
 983         if (wbc->sync_mode == WB_SYNC_NONE) {
 984
 985                 if (wbc->for_kupdate)
 986                         return 0;
 987
 988                 fs_info = BTRFS_I(mapping->host)->root->fs_info;
 989                 /* this is a bit racy, but that's ok */
 990                 ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 991                                              BTRFS_DIRTY_METADATA_THRESH,
 992                                              fs_info->dirty_metadata_batch);
 993                 if (ret < 0)
 994                         return 0;
 995         }
 996         return btree_write_cache_pages(mapping, wbc);
 997 }
 998
 999 static int btree_releasepage(struct page *page, gfp_t gfp_flags)
1000 {
1001         if (PageWriteback(page) || PageDirty(page))
1002                 return 0;
1003
1004         return try_release_extent_buffer(page);
1005 }
1006
1007 static void btree_invalidate_folio(struct folio *folio, size_t offset,
1008                                  size_t length)
1009 {
1010         struct extent_io_tree *tree;
1011         tree = &BTRFS_I(folio->mapping->host)->io_tree;
1012         extent_invalidate_folio(tree, folio, offset);
1013         btree_releasepage(&folio->page, GFP_NOFS);
1014         if (folio_get_private(folio)) {
1015                 btrfs_warn(BTRFS_I(folio->mapping->host)->root->fs_info,
1016                            "folio private not zero on folio %llu",
1017                            (unsigned long long)folio_pos(folio));
1018                 folio_detach_private(folio);
1019         }
1020 }
1021
1022 #ifdef DEBUG
1023 static bool btree_dirty_folio(struct address_space *mapping,
1024                 struct folio *folio)
1025 {
1026         struct btrfs_fs_info *fs_info = btrfs_sb(mapping->host->i_sb);
1027         struct btrfs_subpage *subpage;
1028         struct extent_buffer *eb;
1029         int cur_bit = 0;
1030         u64 page_start = folio_pos(folio);
1031
1032         if (fs_info->sectorsize == PAGE_SIZE) {
1033                 eb = folio_get_private(folio);
1034                 BUG_ON(!eb);
1035                 BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1036                 BUG_ON(!atomic_read(&eb->refs));
1037                 btrfs_assert_tree_write_locked(eb);
1038                 return filemap_dirty_folio(mapping, folio);
1039         }
1040         subpage = folio_get_private(folio);
1041
1042         ASSERT(subpage->dirty_bitmap);
1043         while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) {
1044                 unsigned long flags;
1045                 u64 cur;
1046                 u16 tmp = (1 << cur_bit);
1047
1048                 spin_lock_irqsave(&subpage->lock, flags);
1049                 if (!(tmp & subpage->dirty_bitmap)) {
1050                         spin_unlock_irqrestore(&subpage->lock, flags);
1051                         cur_bit++;
1052                         continue;
1053                 }
1054                 spin_unlock_irqrestore(&subpage->lock, flags);
1055                 cur = page_start + cur_bit * fs_info->sectorsize;
1056
1057                 eb = find_extent_buffer(fs_info, cur);
1058                 ASSERT(eb);
1059                 ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1060                 ASSERT(atomic_read(&eb->refs));
1061                 btrfs_assert_tree_write_locked(eb);
1062                 free_extent_buffer(eb);
1063
1064                 cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits);
1065         }
1066         return filemap_dirty_folio(mapping, folio);
1067 }
1068 #else
1069 #define btree_dirty_folio filemap_dirty_folio
1070 #endif
1071
1072 static const struct address_space_operations btree_aops = {
1073         .writepages     = btree_writepages,
1074         .releasepage    = btree_releasepage,
1075         .invalidate_folio = btree_invalidate_folio,
1076 #ifdef CONFIG_MIGRATION
1077         .migratepage    = btree_migratepage,
1078 #endif
1079         .dirty_folio = btree_dirty_folio,
1080 };
1081
1082 struct extent_buffer *btrfs_find_create_tree_block(
1083                                                 struct btrfs_fs_info *fs_info,
1084                                                 u64 bytenr, u64 owner_root,
1085                                                 int level)
1086 {
1087         if (btrfs_is_testing(fs_info))
1088                 return alloc_test_extent_buffer(fs_info, bytenr);
1089         return alloc_extent_buffer(fs_info, bytenr, owner_root, level);
1090 }
1091
1092 /*
1093  * Read tree block at logical address @bytenr and do variant basic but critical
1094  * verification.
1095  *
1096  * @owner_root:         the objectid of the root owner for this block.
1097  * @parent_transid:     expected transid of this tree block, skip check if 0
1098  * @level:              expected level, mandatory check
1099  * @first_key:          expected key in slot 0, skip check if NULL
1100  */
1101 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
1102                                       u64 owner_root, u64 parent_transid,
1103                                       int level, struct btrfs_key *first_key)
1104 {
1105         struct extent_buffer *buf = NULL;
1106         int ret;
1107
1108         buf = btrfs_find_create_tree_block(fs_info, bytenr, owner_root, level);
1109         if (IS_ERR(buf))
1110                 return buf;
1111
1112         ret = btrfs_read_extent_buffer(buf, parent_transid, level, first_key);
1113         if (ret) {
1114                 free_extent_buffer_stale(buf);
1115                 return ERR_PTR(ret);
1116         }
1117         if (btrfs_check_eb_owner(buf, owner_root)) {
1118                 free_extent_buffer_stale(buf);
1119                 return ERR_PTR(-EUCLEAN);
1120         }
1121         return buf;
1122
1123 }
1124
1125 void btrfs_clean_tree_block(struct extent_buffer *buf)
1126 {
1127         struct btrfs_fs_info *fs_info = buf->fs_info;
1128         if (btrfs_header_generation(buf) ==
1129             fs_info->running_transaction->transid) {
1130                 btrfs_assert_tree_write_locked(buf);
1131
1132                 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1133                         percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
1134                                                  -buf->len,
1135                                                  fs_info->dirty_metadata_batch);
1136                         clear_extent_buffer_dirty(buf);
1137                 }
1138         }
1139 }
1140
1141 static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
1142                          u64 objectid)
1143 {
1144         bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
1145
1146         memset(&root->root_key, 0, sizeof(root->root_key));
1147         memset(&root->root_item, 0, sizeof(root->root_item));
1148         memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1149         root->fs_info = fs_info;
1150         root->root_key.objectid = objectid;
1151         root->node = NULL;
1152         root->commit_root = NULL;
1153         root->state = 0;
1154         RB_CLEAR_NODE(&root->rb_node);
1155
1156         root->last_trans = 0;
1157         root->free_objectid = 0;
1158         root->nr_delalloc_inodes = 0;
1159         root->nr_ordered_extents = 0;
1160         root->inode_tree = RB_ROOT;
1161         xa_init_flags(&root->delayed_nodes, GFP_ATOMIC);
1162
1163         btrfs_init_root_block_rsv(root);
1164
1165         INIT_LIST_HEAD(&root->dirty_list);
1166         INIT_LIST_HEAD(&root->root_list);
1167         INIT_LIST_HEAD(&root->delalloc_inodes);
1168         INIT_LIST_HEAD(&root->delalloc_root);
1169         INIT_LIST_HEAD(&root->ordered_extents);
1170         INIT_LIST_HEAD(&root->ordered_root);
1171         INIT_LIST_HEAD(&root->reloc_dirty_list);
1172         INIT_LIST_HEAD(&root->logged_list[0]);
1173         INIT_LIST_HEAD(&root->logged_list[1]);
1174         spin_lock_init(&root->inode_lock);
1175         spin_lock_init(&root->delalloc_lock);
1176         spin_lock_init(&root->ordered_extent_lock);
1177         spin_lock_init(&root->accounting_lock);
1178         spin_lock_init(&root->log_extents_lock[0]);
1179         spin_lock_init(&root->log_extents_lock[1]);
1180         spin_lock_init(&root->qgroup_meta_rsv_lock);
1181         mutex_init(&root->objectid_mutex);
1182         mutex_init(&root->log_mutex);
1183         mutex_init(&root->ordered_extent_mutex);
1184         mutex_init(&root->delalloc_mutex);
1185         init_waitqueue_head(&root->qgroup_flush_wait);
1186         init_waitqueue_head(&root->log_writer_wait);
1187         init_waitqueue_head(&root->log_commit_wait[0]);
1188         init_waitqueue_head(&root->log_commit_wait[1]);
1189         INIT_LIST_HEAD(&root->log_ctxs[0]);
1190         INIT_LIST_HEAD(&root->log_ctxs[1]);
1191         atomic_set(&root->log_commit[0], 0);
1192         atomic_set(&root->log_commit[1], 0);
1193         atomic_set(&root->log_writers, 0);
1194         atomic_set(&root->log_batch, 0);
1195         refcount_set(&root->refs, 1);
1196         atomic_set(&root->snapshot_force_cow, 0);
1197         atomic_set(&root->nr_swapfiles, 0);
1198         root->log_transid = 0;
1199         root->log_transid_committed = -1;
1200         root->last_log_commit = 0;
1201         root->anon_dev = 0;
1202         if (!dummy) {
1203                 extent_io_tree_init(fs_info, &root->dirty_log_pages,
1204                                     IO_TREE_ROOT_DIRTY_LOG_PAGES, NULL);
1205                 extent_io_tree_init(fs_info, &root->log_csum_range,
1206                                     IO_TREE_LOG_CSUM_RANGE, NULL);
1207         }
1208
1209         spin_lock_init(&root->root_item_lock);
1210         btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks);
1211 #ifdef CONFIG_BTRFS_DEBUG
1212         INIT_LIST_HEAD(&root->leak_list);
1213         spin_lock(&fs_info->fs_roots_lock);
1214         list_add_tail(&root->leak_list, &fs_info->allocated_roots);
1215         spin_unlock(&fs_info->fs_roots_lock);
1216 #endif
1217 }
1218
1219 static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1220                                            u64 objectid, gfp_t flags)
1221 {
1222         struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1223         if (root)
1224                 __setup_root(root, fs_info, objectid);
1225         return root;
1226 }
1227
1228 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1229 /* Should only be used by the testing infrastructure */
1230 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
1231 {
1232         struct btrfs_root *root;
1233
1234         if (!fs_info)
1235                 return ERR_PTR(-EINVAL);
1236
1237         root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
1238         if (!root)
1239                 return ERR_PTR(-ENOMEM);
1240
1241         /* We don't use the stripesize in selftest, set it as sectorsize */
1242         root->alloc_bytenr = 0;
1243
1244         return root;
1245 }
1246 #endif
1247
1248 static int global_root_cmp(struct rb_node *a_node, const struct rb_node *b_node)
1249 {
1250         const struct btrfs_root *a = rb_entry(a_node, struct btrfs_root, rb_node);
1251         const struct btrfs_root *b = rb_entry(b_node, struct btrfs_root, rb_node);
1252
1253         return btrfs_comp_cpu_keys(&a->root_key, &b->root_key);
1254 }
1255
1256 static int global_root_key_cmp(const void *k, const struct rb_node *node)
1257 {
1258         const struct btrfs_key *key = k;
1259         const struct btrfs_root *root = rb_entry(node, struct btrfs_root, rb_node);
1260
1261         return btrfs_comp_cpu_keys(key, &root->root_key);
1262 }
1263
1264 int btrfs_global_root_insert(struct btrfs_root *root)
1265 {
1266         struct btrfs_fs_info *fs_info = root->fs_info;
1267         struct rb_node *tmp;
1268
1269         write_lock(&fs_info->global_root_lock);
1270         tmp = rb_find_add(&root->rb_node, &fs_info->global_root_tree, global_root_cmp);
1271         write_unlock(&fs_info->global_root_lock);
1272         ASSERT(!tmp);
1273
1274         return tmp ? -EEXIST : 0;
1275 }
1276
1277 void btrfs_global_root_delete(struct btrfs_root *root)
1278 {
1279         struct btrfs_fs_info *fs_info = root->fs_info;
1280
1281         write_lock(&fs_info->global_root_lock);
1282         rb_erase(&root->rb_node, &fs_info->global_root_tree);
1283         write_unlock(&fs_info->global_root_lock);
1284 }
1285
1286 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
1287                                      struct btrfs_key *key)
1288 {
1289         struct rb_node *node;
1290         struct btrfs_root *root = NULL;
1291
1292         read_lock(&fs_info->global_root_lock);
1293         node = rb_find(key, &fs_info->global_root_tree, global_root_key_cmp);
1294         if (node)
1295                 root = container_of(node, struct btrfs_root, rb_node);
1296         read_unlock(&fs_info->global_root_lock);
1297
1298         return root;
1299 }
1300
1301 static u64 btrfs_global_root_id(struct btrfs_fs_info *fs_info, u64 bytenr)
1302 {
1303         struct btrfs_block_group *block_group;
1304         u64 ret;
1305
1306         if (!btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1307                 return 0;
1308
1309         if (bytenr)
1310                 block_group = btrfs_lookup_block_group(fs_info, bytenr);
1311         else
1312                 block_group = btrfs_lookup_first_block_group(fs_info, bytenr);
1313         ASSERT(block_group);
1314         if (!block_group)
1315                 return 0;
1316         ret = block_group->global_root_id;
1317         btrfs_put_block_group(block_group);
1318
1319         return ret;
1320 }
1321
1322 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr)
1323 {
1324         struct btrfs_key key = {
1325                 .objectid = BTRFS_CSUM_TREE_OBJECTID,
1326                 .type = BTRFS_ROOT_ITEM_KEY,
1327                 .offset = btrfs_global_root_id(fs_info, bytenr),
1328         };
1329
1330         return btrfs_global_root(fs_info, &key);
1331 }
1332
1333 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr)
1334 {
1335         struct btrfs_key key = {
1336                 .objectid = BTRFS_EXTENT_TREE_OBJECTID,
1337                 .type = BTRFS_ROOT_ITEM_KEY,
1338                 .offset = btrfs_global_root_id(fs_info, bytenr),
1339         };
1340
1341         return btrfs_global_root(fs_info, &key);
1342 }
1343
1344 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1345                                      u64 objectid)
1346 {
1347         struct btrfs_fs_info *fs_info = trans->fs_info;
1348         struct extent_buffer *leaf;
1349         struct btrfs_root *tree_root = fs_info->tree_root;
1350         struct btrfs_root *root;
1351         struct btrfs_key key;
1352         unsigned int nofs_flag;
1353         int ret = 0;
1354
1355         /*
1356          * We're holding a transaction handle, so use a NOFS memory allocation
1357          * context to avoid deadlock if reclaim happens.
1358          */
1359         nofs_flag = memalloc_nofs_save();
1360         root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL);
1361         memalloc_nofs_restore(nofs_flag);
1362         if (!root)
1363                 return ERR_PTR(-ENOMEM);
1364
1365         root->root_key.objectid = objectid;
1366         root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1367         root->root_key.offset = 0;
1368
1369         leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
1370                                       BTRFS_NESTING_NORMAL);
1371         if (IS_ERR(leaf)) {
1372                 ret = PTR_ERR(leaf);
1373                 leaf = NULL;
1374                 goto fail_unlock;
1375         }
1376
1377         root->node = leaf;
1378         btrfs_mark_buffer_dirty(leaf);
1379
1380         root->commit_root = btrfs_root_node(root);
1381         set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
1382
1383         btrfs_set_root_flags(&root->root_item, 0);
1384         btrfs_set_root_limit(&root->root_item, 0);
1385         btrfs_set_root_bytenr(&root->root_item, leaf->start);
1386         btrfs_set_root_generation(&root->root_item, trans->transid);
1387         btrfs_set_root_level(&root->root_item, 0);
1388         btrfs_set_root_refs(&root->root_item, 1);
1389         btrfs_set_root_used(&root->root_item, leaf->len);
1390         btrfs_set_root_last_snapshot(&root->root_item, 0);
1391         btrfs_set_root_dirid(&root->root_item, 0);
1392         if (is_fstree(objectid))
1393                 generate_random_guid(root->root_item.uuid);
1394         else
1395                 export_guid(root->root_item.uuid, &guid_null);
1396         btrfs_set_root_drop_level(&root->root_item, 0);
1397
1398         btrfs_tree_unlock(leaf);
1399
1400         key.objectid = objectid;
1401         key.type = BTRFS_ROOT_ITEM_KEY;
1402         key.offset = 0;
1403         ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1404         if (ret)
1405                 goto fail;
1406
1407         return root;
1408
1409 fail_unlock:
1410         if (leaf)
1411                 btrfs_tree_unlock(leaf);
1412 fail:
1413         btrfs_put_root(root);
1414
1415         return ERR_PTR(ret);
1416 }
1417
1418 static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1419                                          struct btrfs_fs_info *fs_info)
1420 {
1421         struct btrfs_root *root;
1422
1423         root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
1424         if (!root)
1425                 return ERR_PTR(-ENOMEM);
1426
1427         root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1428         root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1429         root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1430
1431         return root;
1432 }
1433
1434 int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
1435                               struct btrfs_root *root)
1436 {
1437         struct extent_buffer *leaf;
1438
1439         /*
1440          * DON'T set SHAREABLE bit for log trees.
1441          *
1442          * Log trees are not exposed to user space thus can't be snapshotted,
1443          * and they go away before a real commit is actually done.
1444          *
1445          * They do store pointers to file data extents, and those reference
1446          * counts still get updated (along with back refs to the log tree).
1447          */
1448
1449         leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1450                         NULL, 0, 0, 0, BTRFS_NESTING_NORMAL);
1451         if (IS_ERR(leaf))
1452                 return PTR_ERR(leaf);
1453
1454         root->node = leaf;
1455
1456         btrfs_mark_buffer_dirty(root->node);
1457         btrfs_tree_unlock(root->node);
1458
1459         return 0;
1460 }
1461
1462 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1463                              struct btrfs_fs_info *fs_info)
1464 {
1465         struct btrfs_root *log_root;
1466
1467         log_root = alloc_log_tree(trans, fs_info);
1468         if (IS_ERR(log_root))
1469                 return PTR_ERR(log_root);
1470
1471         if (!btrfs_is_zoned(fs_info)) {
1472                 int ret = btrfs_alloc_log_tree_node(trans, log_root);
1473
1474                 if (ret) {
1475                         btrfs_put_root(log_root);
1476                         return ret;
1477                 }
1478         }
1479
1480         WARN_ON(fs_info->log_root_tree);
1481         fs_info->log_root_tree = log_root;
1482         return 0;
1483 }
1484
1485 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1486                        struct btrfs_root *root)
1487 {
1488         struct btrfs_fs_info *fs_info = root->fs_info;
1489         struct btrfs_root *log_root;
1490         struct btrfs_inode_item *inode_item;
1491         int ret;
1492
1493         log_root = alloc_log_tree(trans, fs_info);
1494         if (IS_ERR(log_root))
1495                 return PTR_ERR(log_root);
1496
1497         ret = btrfs_alloc_log_tree_node(trans, log_root);
1498         if (ret) {
1499                 btrfs_put_root(log_root);
1500                 return ret;
1501         }
1502
1503         log_root->last_trans = trans->transid;
1504         log_root->root_key.offset = root->root_key.objectid;
1505
1506         inode_item = &log_root->root_item.inode;
1507         btrfs_set_stack_inode_generation(inode_item, 1);
1508         btrfs_set_stack_inode_size(inode_item, 3);
1509         btrfs_set_stack_inode_nlink(inode_item, 1);
1510         btrfs_set_stack_inode_nbytes(inode_item,
1511                                      fs_info->nodesize);
1512         btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1513
1514         btrfs_set_root_node(&log_root->root_item, log_root->node);
1515
1516         WARN_ON(root->log_root);
1517         root->log_root = log_root;
1518         root->log_transid = 0;
1519         root->log_transid_committed = -1;
1520         root->last_log_commit = 0;
1521         return 0;
1522 }
1523
1524 static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
1525                                               struct btrfs_path *path,
1526                                               struct btrfs_key *key)
1527 {
1528         struct btrfs_root *root;
1529         struct btrfs_fs_info *fs_info = tree_root->fs_info;
1530         u64 generation;
1531         int ret;
1532         int level;
1533
1534         root = btrfs_alloc_root(fs_info, key->objectid, GFP_NOFS);
1535         if (!root)
1536                 return ERR_PTR(-ENOMEM);
1537
1538         ret = btrfs_find_root(tree_root, key, path,
1539                               &root->root_item, &root->root_key);
1540         if (ret) {
1541                 if (ret > 0)
1542                         ret = -ENOENT;
1543                 goto fail;
1544         }
1545
1546         generation = btrfs_root_generation(&root->root_item);
1547         level = btrfs_root_level(&root->root_item);
1548         root->node = read_tree_block(fs_info,
1549                                      btrfs_root_bytenr(&root->root_item),
1550                                      key->objectid, generation, level, NULL);
1551         if (IS_ERR(root->node)) {
1552                 ret = PTR_ERR(root->node);
1553                 root->node = NULL;
1554                 goto fail;
1555         }
1556         if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1557                 ret = -EIO;
1558                 goto fail;
1559         }
1560
1561         /*
1562          * For real fs, and not log/reloc trees, root owner must
1563          * match its root node owner
1564          */
1565         if (!test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state) &&
1566             root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1567             root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
1568             root->root_key.objectid != btrfs_header_owner(root->node)) {
1569                 btrfs_crit(fs_info,
1570 "root=%llu block=%llu, tree root owner mismatch, have %llu expect %llu",
1571                            root->root_key.objectid, root->node->start,
1572                            btrfs_header_owner(root->node),
1573                            root->root_key.objectid);
1574                 ret = -EUCLEAN;
1575                 goto fail;
1576         }
1577         root->commit_root = btrfs_root_node(root);
1578         return root;
1579 fail:
1580         btrfs_put_root(root);
1581         return ERR_PTR(ret);
1582 }
1583
1584 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1585                                         struct btrfs_key *key)
1586 {
1587         struct btrfs_root *root;
1588         struct btrfs_path *path;
1589
1590         path = btrfs_alloc_path();
1591         if (!path)
1592                 return ERR_PTR(-ENOMEM);
1593         root = read_tree_root_path(tree_root, path, key);
1594         btrfs_free_path(path);
1595
1596         return root;
1597 }
1598
1599 /*
1600  * Initialize subvolume root in-memory structure
1601  *
1602  * @anon_dev:   anonymous device to attach to the root, if zero, allocate new
1603  */
1604 static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev)
1605 {
1606         int ret;
1607         unsigned int nofs_flag;
1608
1609         /*
1610          * We might be called under a transaction (e.g. indirect backref
1611          * resolution) which could deadlock if it triggers memory reclaim
1612          */
1613         nofs_flag = memalloc_nofs_save();
1614         ret = btrfs_drew_lock_init(&root->snapshot_lock);
1615         memalloc_nofs_restore(nofs_flag);
1616         if (ret)
1617                 goto fail;
1618
1619         if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1620             !btrfs_is_data_reloc_root(root)) {
1621                 set_bit(BTRFS_ROOT_SHAREABLE, &root->state);
1622                 btrfs_check_and_init_root_item(&root->root_item);
1623         }
1624
1625         /*
1626          * Don't assign anonymous block device to roots that are not exposed to
1627          * userspace, the id pool is limited to 1M
1628          */
1629         if (is_fstree(root->root_key.objectid) &&
1630             btrfs_root_refs(&root->root_item) > 0) {
1631                 if (!anon_dev) {
1632                         ret = get_anon_bdev(&root->anon_dev);
1633                         if (ret)
1634                                 goto fail;
1635                 } else {
1636                         root->anon_dev = anon_dev;
1637                 }
1638         }
1639
1640         mutex_lock(&root->objectid_mutex);
1641         ret = btrfs_init_root_free_objectid(root);
1642         if (ret) {
1643                 mutex_unlock(&root->objectid_mutex);
1644                 goto fail;
1645         }
1646
1647         ASSERT(root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
1648
1649         mutex_unlock(&root->objectid_mutex);
1650
1651         return 0;
1652 fail:
1653         /* The caller is responsible to call btrfs_free_fs_root */
1654         return ret;
1655 }
1656
1657 static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1658                                                u64 root_id)
1659 {
1660         struct btrfs_root *root;
1661
1662         spin_lock(&fs_info->fs_roots_lock);
1663         root = xa_load(&fs_info->fs_roots, (unsigned long)root_id);
1664         if (root)
1665                 root = btrfs_grab_root(root);
1666         spin_unlock(&fs_info->fs_roots_lock);
1667         return root;
1668 }
1669
1670 static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info,
1671                                                 u64 objectid)
1672 {
1673         struct btrfs_key key = {
1674                 .objectid = objectid,
1675                 .type = BTRFS_ROOT_ITEM_KEY,
1676                 .offset = 0,
1677         };
1678
1679         if (objectid == BTRFS_ROOT_TREE_OBJECTID)
1680                 return btrfs_grab_root(fs_info->tree_root);
1681         if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
1682                 return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1683         if (objectid == BTRFS_CHUNK_TREE_OBJECTID)
1684                 return btrfs_grab_root(fs_info->chunk_root);
1685         if (objectid == BTRFS_DEV_TREE_OBJECTID)
1686                 return btrfs_grab_root(fs_info->dev_root);
1687         if (objectid == BTRFS_CSUM_TREE_OBJECTID)
1688                 return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1689         if (objectid == BTRFS_QUOTA_TREE_OBJECTID)
1690                 return btrfs_grab_root(fs_info->quota_root) ?
1691                         fs_info->quota_root : ERR_PTR(-ENOENT);
1692         if (objectid == BTRFS_UUID_TREE_OBJECTID)
1693                 return btrfs_grab_root(fs_info->uuid_root) ?
1694                         fs_info->uuid_root : ERR_PTR(-ENOENT);
1695         if (objectid == BTRFS_FREE_SPACE_TREE_OBJECTID) {
1696                 struct btrfs_root *root = btrfs_global_root(fs_info, &key);
1697
1698                 return btrfs_grab_root(root) ? root : ERR_PTR(-ENOENT);
1699         }
1700         return NULL;
1701 }
1702
1703 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1704                          struct btrfs_root *root)
1705 {
1706         int ret;
1707
1708         spin_lock(&fs_info->fs_roots_lock);
1709         ret = xa_insert(&fs_info->fs_roots, (unsigned long)root->root_key.objectid,
1710                         root, GFP_NOFS);
1711         if (ret == 0) {
1712                 btrfs_grab_root(root);
1713                 set_bit(BTRFS_ROOT_REGISTERED, &root->state);
1714         }
1715         spin_unlock(&fs_info->fs_roots_lock);
1716
1717         return ret;
1718 }
1719
1720 void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info)
1721 {
1722 #ifdef CONFIG_BTRFS_DEBUG
1723         struct btrfs_root *root;
1724
1725         while (!list_empty(&fs_info->allocated_roots)) {
1726                 char buf[BTRFS_ROOT_NAME_BUF_LEN];
1727
1728                 root = list_first_entry(&fs_info->allocated_roots,
1729                                         struct btrfs_root, leak_list);
1730                 btrfs_err(fs_info, "leaked root %s refcount %d",
1731                           btrfs_root_name(&root->root_key, buf),
1732                           refcount_read(&root->refs));
1733                 while (refcount_read(&root->refs) > 1)
1734                         btrfs_put_root(root);
1735                 btrfs_put_root(root);
1736         }
1737 #endif
1738 }
1739
1740 static void free_global_roots(struct btrfs_fs_info *fs_info)
1741 {
1742         struct btrfs_root *root;
1743         struct rb_node *node;
1744
1745         while ((node = rb_first_postorder(&fs_info->global_root_tree)) != NULL) {
1746                 root = rb_entry(node, struct btrfs_root, rb_node);
1747                 rb_erase(&root->rb_node, &fs_info->global_root_tree);
1748                 btrfs_put_root(root);
1749         }
1750 }
1751
1752 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
1753 {
1754         percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
1755         percpu_counter_destroy(&fs_info->delalloc_bytes);
1756         percpu_counter_destroy(&fs_info->ordered_bytes);
1757         percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
1758         btrfs_free_csum_hash(fs_info);
1759         btrfs_free_stripe_hash_table(fs_info);
1760         btrfs_free_ref_cache(fs_info);
1761         kfree(fs_info->balance_ctl);
1762         kfree(fs_info->delayed_root);
1763         free_global_roots(fs_info);
1764         btrfs_put_root(fs_info->tree_root);
1765         btrfs_put_root(fs_info->chunk_root);
1766         btrfs_put_root(fs_info->dev_root);
1767         btrfs_put_root(fs_info->quota_root);
1768         btrfs_put_root(fs_info->uuid_root);
1769         btrfs_put_root(fs_info->fs_root);
1770         btrfs_put_root(fs_info->data_reloc_root);
1771         btrfs_put_root(fs_info->block_group_root);
1772         btrfs_check_leaked_roots(fs_info);
1773         btrfs_extent_buffer_leak_debug_check(fs_info);
1774         kfree(fs_info->super_copy);
1775         kfree(fs_info->super_for_commit);
1776         kfree(fs_info->subpage_info);
1777         kvfree(fs_info);
1778 }
1779
1780
1781 /*
1782  * Get an in-memory reference of a root structure.
1783  *
1784  * For essential trees like root/extent tree, we grab it from fs_info directly.
1785  * For subvolume trees, we check the cached filesystem roots first. If not
1786  * found, then read it from disk and add it to cached fs roots.
1787  *
1788  * Caller should release the root by calling btrfs_put_root() after the usage.
1789  *
1790  * NOTE: Reloc and log trees can't be read by this function as they share the
1791  *       same root objectid.
1792  *
1793  * @objectid:   root id
1794  * @anon_dev:   preallocated anonymous block device number for new roots,
1795  *              pass 0 for new allocation.
1796  * @check_ref:  whether to check root item references, If true, return -ENOENT
1797  *              for orphan roots
1798  */
1799 static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info,
1800                                              u64 objectid, dev_t anon_dev,
1801                                              bool check_ref)
1802 {
1803         struct btrfs_root *root;
1804         struct btrfs_path *path;
1805         struct btrfs_key key;
1806         int ret;
1807
1808         root = btrfs_get_global_root(fs_info, objectid);
1809         if (root)
1810                 return root;
1811 again:
1812         root = btrfs_lookup_fs_root(fs_info, objectid);
1813         if (root) {
1814                 /* Shouldn't get preallocated anon_dev for cached roots */
1815                 ASSERT(!anon_dev);
1816                 if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1817                         btrfs_put_root(root);
1818                         return ERR_PTR(-ENOENT);
1819                 }
1820                 return root;
1821         }
1822
1823         key.objectid = objectid;
1824         key.type = BTRFS_ROOT_ITEM_KEY;
1825         key.offset = (u64)-1;
1826         root = btrfs_read_tree_root(fs_info->tree_root, &key);
1827         if (IS_ERR(root))
1828                 return root;
1829
1830         if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1831                 ret = -ENOENT;
1832                 goto fail;
1833         }
1834
1835         ret = btrfs_init_fs_root(root, anon_dev);
1836         if (ret)
1837                 goto fail;
1838
1839         path = btrfs_alloc_path();
1840         if (!path) {
1841                 ret = -ENOMEM;
1842                 goto fail;
1843         }
1844         key.objectid = BTRFS_ORPHAN_OBJECTID;
1845         key.type = BTRFS_ORPHAN_ITEM_KEY;
1846         key.offset = objectid;
1847
1848         ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1849         btrfs_free_path(path);
1850         if (ret < 0)
1851                 goto fail;
1852         if (ret == 0)
1853                 set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1854
1855         ret = btrfs_insert_fs_root(fs_info, root);
1856         if (ret) {
1857                 if (ret == -EEXIST) {
1858                         btrfs_put_root(root);
1859                         goto again;
1860                 }
1861                 goto fail;
1862         }
1863         return root;
1864 fail:
1865         /*
1866          * If our caller provided us an anonymous device, then it's his
1867          * responsability to free it in case we fail. So we have to set our
1868          * root's anon_dev to 0 to avoid a double free, once by btrfs_put_root()
1869          * and once again by our caller.
1870          */
1871         if (anon_dev)
1872                 root->anon_dev = 0;
1873         btrfs_put_root(root);
1874         return ERR_PTR(ret);
1875 }
1876
1877 /*
1878  * Get in-memory reference of a root structure
1879  *
1880  * @objectid:   tree objectid
1881  * @check_ref:  if set, verify that the tree exists and the item has at least
1882  *              one reference
1883  */
1884 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1885                                      u64 objectid, bool check_ref)
1886 {
1887         return btrfs_get_root_ref(fs_info, objectid, 0, check_ref);
1888 }
1889
1890 /*
1891  * Get in-memory reference of a root structure, created as new, optionally pass
1892  * the anonymous block device id
1893  *
1894  * @objectid:   tree objectid
1895  * @anon_dev:   if zero, allocate a new anonymous block device or use the
1896  *              parameter value
1897  */
1898 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
1899                                          u64 objectid, dev_t anon_dev)
1900 {
1901         return btrfs_get_root_ref(fs_info, objectid, anon_dev, true);
1902 }
1903
1904 /*
1905  * btrfs_get_fs_root_commit_root - return a root for the given objectid
1906  * @fs_info:    the fs_info
1907  * @objectid:   the objectid we need to lookup
1908  *
1909  * This is exclusively used for backref walking, and exists specifically because
1910  * of how qgroups does lookups.  Qgroups will do a backref lookup at delayed ref
1911  * creation time, which means we may have to read the tree_root in order to look
1912  * up a fs root that is not in memory.  If the root is not in memory we will
1913  * read the tree root commit root and look up the fs root from there.  This is a
1914  * temporary root, it will not be inserted into the radix tree as it doesn't
1915  * have the most uptodate information, it'll simply be discarded once the
1916  * backref code is finished using the root.
1917  */
1918 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
1919                                                  struct btrfs_path *path,
1920                                                  u64 objectid)
1921 {
1922         struct btrfs_root *root;
1923         struct btrfs_key key;
1924
1925         ASSERT(path->search_commit_root && path->skip_locking);
1926
1927         /*
1928          * This can return -ENOENT if we ask for a root that doesn't exist, but
1929          * since this is called via the backref walking code we won't be looking
1930          * up a root that doesn't exist, unless there's corruption.  So if root
1931          * != NULL just return it.
1932          */
1933         root = btrfs_get_global_root(fs_info, objectid);
1934         if (root)
1935                 return root;
1936
1937         root = btrfs_lookup_fs_root(fs_info, objectid);
1938         if (root)
1939                 return root;
1940
1941         key.objectid = objectid;
1942         key.type = BTRFS_ROOT_ITEM_KEY;
1943         key.offset = (u64)-1;
1944         root = read_tree_root_path(fs_info->tree_root, path, &key);
1945         btrfs_release_path(path);
1946
1947         return root;
1948 }
1949
1950 /*
1951  * called by the kthread helper functions to finally call the bio end_io
1952  * functions.  This is where read checksum verification actually happens
1953  */
1954 static void end_workqueue_fn(struct btrfs_work *work)
1955 {
1956         struct bio *bio;
1957         struct btrfs_end_io_wq *end_io_wq;
1958
1959         end_io_wq = container_of(work, struct btrfs_end_io_wq, work);
1960         bio = end_io_wq->bio;
1961
1962         bio->bi_status = end_io_wq->status;
1963         bio->bi_private = end_io_wq->private;
1964         bio->bi_end_io = end_io_wq->end_io;
1965         bio_endio(bio);
1966         kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
1967 }
1968
1969 static int cleaner_kthread(void *arg)
1970 {
1971         struct btrfs_fs_info *fs_info = arg;
1972         int again;
1973
1974         while (1) {
1975                 again = 0;
1976
1977                 set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1978
1979                 /* Make the cleaner go to sleep early. */
1980                 if (btrfs_need_cleaner_sleep(fs_info))
1981                         goto sleep;
1982
1983                 /*
1984                  * Do not do anything if we might cause open_ctree() to block
1985                  * before we have finished mounting the filesystem.
1986                  */
1987                 if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1988                         goto sleep;
1989
1990                 if (!mutex_trylock(&fs_info->cleaner_mutex))
1991                         goto sleep;
1992
1993                 /*
1994                  * Avoid the problem that we change the status of the fs
1995                  * during the above check and trylock.
1996                  */
1997                 if (btrfs_need_cleaner_sleep(fs_info)) {
1998                         mutex_unlock(&fs_info->cleaner_mutex);
1999                         goto sleep;
2000                 }
2001
2002                 btrfs_run_delayed_iputs(fs_info);
2003
2004                 again = btrfs_clean_one_deleted_snapshot(fs_info);
2005                 mutex_unlock(&fs_info->cleaner_mutex);
2006
2007                 /*
2008                  * The defragger has dealt with the R/O remount and umount,
2009                  * needn't do anything special here.
2010                  */
2011                 btrfs_run_defrag_inodes(fs_info);
2012
2013                 /*
2014                  * Acquires fs_info->reclaim_bgs_lock to avoid racing
2015                  * with relocation (btrfs_relocate_chunk) and relocation
2016                  * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
2017                  * after acquiring fs_info->reclaim_bgs_lock. So we
2018                  * can't hold, nor need to, fs_info->cleaner_mutex when deleting
2019                  * unused block groups.
2020                  */
2021                 btrfs_delete_unused_bgs(fs_info);
2022
2023                 /*
2024                  * Reclaim block groups in the reclaim_bgs list after we deleted
2025                  * all unused block_groups. This possibly gives us some more free
2026                  * space.
2027                  */
2028                 btrfs_reclaim_bgs(fs_info);
2029 sleep:
2030                 clear_and_wake_up_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
2031                 if (kthread_should_park())
2032                         kthread_parkme();
2033                 if (kthread_should_stop())
2034                         return 0;
2035                 if (!again) {
2036                         set_current_state(TASK_INTERRUPTIBLE);
2037                         schedule();
2038                         __set_current_state(TASK_RUNNING);
2039                 }
2040         }
2041 }
2042
2043 static int transaction_kthread(void *arg)
2044 {
2045         struct btrfs_root *root = arg;
2046         struct btrfs_fs_info *fs_info = root->fs_info;
2047         struct btrfs_trans_handle *trans;
2048         struct btrfs_transaction *cur;
2049         u64 transid;
2050         time64_t delta;
2051         unsigned long delay;
2052         bool cannot_commit;
2053
2054         do {
2055                 cannot_commit = false;
2056                 delay = msecs_to_jiffies(fs_info->commit_interval * 1000);
2057                 mutex_lock(&fs_info->transaction_kthread_mutex);
2058
2059                 spin_lock(&fs_info->trans_lock);
2060                 cur = fs_info->running_transaction;
2061                 if (!cur) {
2062                         spin_unlock(&fs_info->trans_lock);
2063                         goto sleep;
2064                 }
2065
2066                 delta = ktime_get_seconds() - cur->start_time;
2067                 if (!test_and_clear_bit(BTRFS_FS_COMMIT_TRANS, &fs_info->flags) &&
2068                     cur->state < TRANS_STATE_COMMIT_START &&
2069                     delta < fs_info->commit_interval) {
2070                         spin_unlock(&fs_info->trans_lock);
2071                         delay -= msecs_to_jiffies((delta - 1) * 1000);
2072                         delay = min(delay,
2073                                     msecs_to_jiffies(fs_info->commit_interval * 1000));
2074                         goto sleep;
2075                 }
2076                 transid = cur->transid;
2077                 spin_unlock(&fs_info->trans_lock);
2078
2079                 /* If the file system is aborted, this will always fail. */
2080                 trans = btrfs_attach_transaction(root);
2081                 if (IS_ERR(trans)) {
2082                         if (PTR_ERR(trans) != -ENOENT)
2083                                 cannot_commit = true;
2084                         goto sleep;
2085                 }
2086                 if (transid == trans->transid) {
2087                         btrfs_commit_transaction(trans);
2088                 } else {
2089                         btrfs_end_transaction(trans);
2090                 }
2091 sleep:
2092                 wake_up_process(fs_info->cleaner_kthread);
2093                 mutex_unlock(&fs_info->transaction_kthread_mutex);
2094
2095                 if (BTRFS_FS_ERROR(fs_info))
2096                         btrfs_cleanup_transaction(fs_info);
2097                 if (!kthread_should_stop() &&
2098                                 (!btrfs_transaction_blocked(fs_info) ||
2099                                  cannot_commit))
2100                         schedule_timeout_interruptible(delay);
2101         } while (!kthread_should_stop());
2102         return 0;
2103 }
2104
2105 /*
2106  * This will find the highest generation in the array of root backups.  The
2107  * index of the highest array is returned, or -EINVAL if we can't find
2108  * anything.
2109  *
2110  * We check to make sure the array is valid by comparing the
2111  * generation of the latest  root in the array with the generation
2112  * in the super block.  If they don't match we pitch it.
2113  */
2114 static int find_newest_super_backup(struct btrfs_fs_info *info)
2115 {
2116         const u64 newest_gen = btrfs_super_generation(info->super_copy);
2117         u64 cur;
2118         struct btrfs_root_backup *root_backup;
2119         int i;
2120
2121         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2122                 root_backup = info->super_copy->super_roots + i;
2123                 cur = btrfs_backup_tree_root_gen(root_backup);
2124                 if (cur == newest_gen)
2125                         return i;
2126         }
2127
2128         return -EINVAL;
2129 }
2130
2131 /*
2132  * copy all the root pointers into the super backup array.
2133  * this will bump the backup pointer by one when it is
2134  * done
2135  */
2136 static void backup_super_roots(struct btrfs_fs_info *info)
2137 {
2138         const int next_backup = info->backup_root_index;
2139         struct btrfs_root_backup *root_backup;
2140
2141         root_backup = info->super_for_commit->super_roots + next_backup;
2142
2143         /*
2144          * make sure all of our padding and empty slots get zero filled
2145          * regardless of which ones we use today
2146          */
2147         memset(root_backup, 0, sizeof(*root_backup));
2148
2149         info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
2150
2151         btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
2152         btrfs_set_backup_tree_root_gen(root_backup,
2153                                btrfs_header_generation(info->tree_root->node));
2154
2155         btrfs_set_backup_tree_root_level(root_backup,
2156                                btrfs_header_level(info->tree_root->node));
2157
2158         btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
2159         btrfs_set_backup_chunk_root_gen(root_backup,
2160                                btrfs_header_generation(info->chunk_root->node));
2161         btrfs_set_backup_chunk_root_level(root_backup,
2162                                btrfs_header_level(info->chunk_root->node));
2163
2164         if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) {
2165                 btrfs_set_backup_block_group_root(root_backup,
2166                                         info->block_group_root->node->start);
2167                 btrfs_set_backup_block_group_root_gen(root_backup,
2168                         btrfs_header_generation(info->block_group_root->node));
2169                 btrfs_set_backup_block_group_root_level(root_backup,
2170                         btrfs_header_level(info->block_group_root->node));
2171         } else {
2172                 struct btrfs_root *extent_root = btrfs_extent_root(info, 0);
2173                 struct btrfs_root *csum_root = btrfs_csum_root(info, 0);
2174
2175                 btrfs_set_backup_extent_root(root_backup,
2176                                              extent_root->node->start);
2177                 btrfs_set_backup_extent_root_gen(root_backup,
2178                                 btrfs_header_generation(extent_root->node));
2179                 btrfs_set_backup_extent_root_level(root_backup,
2180                                         btrfs_header_level(extent_root->node));
2181
2182                 btrfs_set_backup_csum_root(root_backup, csum_root->node->start);
2183                 btrfs_set_backup_csum_root_gen(root_backup,
2184                                                btrfs_header_generation(csum_root->node));
2185                 btrfs_set_backup_csum_root_level(root_backup,
2186                                                  btrfs_header_level(csum_root->node));
2187         }
2188
2189         /*
2190          * we might commit during log recovery, which happens before we set
2191          * the fs_root.  Make sure it is valid before we fill it in.
2192          */
2193         if (info->fs_root && info->fs_root->node) {
2194                 btrfs_set_backup_fs_root(root_backup,
2195                                          info->fs_root->node->start);
2196                 btrfs_set_backup_fs_root_gen(root_backup,
2197                                btrfs_header_generation(info->fs_root->node));
2198                 btrfs_set_backup_fs_root_level(root_backup,
2199                                btrfs_header_level(info->fs_root->node));
2200         }
2201
2202         btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
2203         btrfs_set_backup_dev_root_gen(root_backup,
2204                                btrfs_header_generation(info->dev_root->node));
2205         btrfs_set_backup_dev_root_level(root_backup,
2206                                        btrfs_header_level(info->dev_root->node));
2207
2208         btrfs_set_backup_total_bytes(root_backup,
2209                              btrfs_super_total_bytes(info->super_copy));
2210         btrfs_set_backup_bytes_used(root_backup,
2211                              btrfs_super_bytes_used(info->super_copy));
2212         btrfs_set_backup_num_devices(root_backup,
2213                              btrfs_super_num_devices(info->super_copy));
2214
2215         /*
2216          * if we don't copy this out to the super_copy, it won't get remembered
2217          * for the next commit
2218          */
2219         memcpy(&info->super_copy->super_roots,
2220                &info->super_for_commit->super_roots,
2221                sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
2222 }
2223
2224 /*
2225  * read_backup_root - Reads a backup root based on the passed priority. Prio 0
2226  * is the newest, prio 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots
2227  *
2228  * fs_info - filesystem whose backup roots need to be read
2229  * priority - priority of backup root required
2230  *
2231  * Returns backup root index on success and -EINVAL otherwise.
2232  */
2233 static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority)
2234 {
2235         int backup_index = find_newest_super_backup(fs_info);
2236         struct btrfs_super_block *super = fs_info->super_copy;
2237         struct btrfs_root_backup *root_backup;
2238
2239         if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) {
2240                 if (priority == 0)
2241                         return backup_index;
2242
2243                 backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority;
2244                 backup_index %= BTRFS_NUM_BACKUP_ROOTS;
2245         } else {
2246                 return -EINVAL;
2247         }
2248
2249         root_backup = super->super_roots + backup_index;
2250
2251         btrfs_set_super_generation(super,
2252                                    btrfs_backup_tree_root_gen(root_backup));
2253         btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
2254         btrfs_set_super_root_level(super,
2255                                    btrfs_backup_tree_root_level(root_backup));
2256         btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
2257
2258         /*
2259          * Fixme: the total bytes and num_devices need to match or we should
2260          * need a fsck
2261          */
2262         btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
2263         btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
2264
2265         return backup_index;
2266 }
2267
2268 /* helper to cleanup workers */
2269 static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
2270 {
2271         btrfs_destroy_workqueue(fs_info->fixup_workers);
2272         btrfs_destroy_workqueue(fs_info->delalloc_workers);
2273         btrfs_destroy_workqueue(fs_info->hipri_workers);
2274         btrfs_destroy_workqueue(fs_info->workers);
2275         btrfs_destroy_workqueue(fs_info->endio_workers);
2276         btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
2277         if (fs_info->rmw_workers)
2278                 destroy_workqueue(fs_info->rmw_workers);
2279         btrfs_destroy_workqueue(fs_info->endio_write_workers);
2280         btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
2281         btrfs_destroy_workqueue(fs_info->delayed_workers);
2282         btrfs_destroy_workqueue(fs_info->caching_workers);
2283         btrfs_destroy_workqueue(fs_info->flush_workers);
2284         btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
2285         if (fs_info->discard_ctl.discard_workers)
2286                 destroy_workqueue(fs_info->discard_ctl.discard_workers);
2287         /*
2288          * Now that all other work queues are destroyed, we can safely destroy
2289          * the queues used for metadata I/O, since tasks from those other work
2290          * queues can do metadata I/O operations.
2291          */
2292         btrfs_destroy_workqueue(fs_info->endio_meta_workers);
2293         btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
2294 }
2295
2296 static void free_root_extent_buffers(struct btrfs_root *root)
2297 {
2298         if (root) {
2299                 free_extent_buffer(root->node);
2300                 free_extent_buffer(root->commit_root);
2301                 root->node = NULL;
2302                 root->commit_root = NULL;
2303         }
2304 }
2305
2306 static void free_global_root_pointers(struct btrfs_fs_info *fs_info)
2307 {
2308         struct btrfs_root *root, *tmp;
2309
2310         rbtree_postorder_for_each_entry_safe(root, tmp,
2311                                              &fs_info->global_root_tree,
2312                                              rb_node)
2313                 free_root_extent_buffers(root);
2314 }
2315
2316 /* helper to cleanup tree roots */
2317 static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
2318 {
2319         free_root_extent_buffers(info->tree_root);
2320
2321         free_global_root_pointers(info);
2322         free_root_extent_buffers(info->dev_root);
2323         free_root_extent_buffers(info->quota_root);
2324         free_root_extent_buffers(info->uuid_root);
2325         free_root_extent_buffers(info->fs_root);
2326         free_root_extent_buffers(info->data_reloc_root);
2327         free_root_extent_buffers(info->block_group_root);
2328         if (free_chunk_root)
2329                 free_root_extent_buffers(info->chunk_root);
2330 }
2331
2332 void btrfs_put_root(struct btrfs_root *root)
2333 {
2334         if (!root)
2335                 return;
2336
2337         if (refcount_dec_and_test(&root->refs)) {
2338                 WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2339                 WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
2340                 if (root->anon_dev)
2341                         free_anon_bdev(root->anon_dev);
2342                 btrfs_drew_lock_destroy(&root->snapshot_lock);
2343                 free_root_extent_buffers(root);
2344 #ifdef CONFIG_BTRFS_DEBUG
2345                 spin_lock(&root->fs_info->fs_roots_lock);
2346                 list_del_init(&root->leak_list);
2347                 spin_unlock(&root->fs_info->fs_roots_lock);
2348 #endif
2349                 kfree(root);
2350         }
2351 }
2352
2353 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2354 {
2355         struct btrfs_root *root;
2356         unsigned long index = 0;
2357
2358         while (!list_empty(&fs_info->dead_roots)) {
2359                 root = list_entry(fs_info->dead_roots.next,
2360                                   struct btrfs_root, root_list);
2361                 list_del(&root->root_list);
2362
2363                 if (test_bit(BTRFS_ROOT_REGISTERED, &root->state))
2364                         btrfs_drop_and_free_fs_root(fs_info, root);
2365                 btrfs_put_root(root);
2366         }
2367
2368         xa_for_each(&fs_info->fs_roots, index, root) {
2369                 btrfs_drop_and_free_fs_root(fs_info, root);
2370         }
2371 }
2372
2373 static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2374 {
2375         mutex_init(&fs_info->scrub_lock);
2376         atomic_set(&fs_info->scrubs_running, 0);
2377         atomic_set(&fs_info->scrub_pause_req, 0);
2378         atomic_set(&fs_info->scrubs_paused, 0);
2379         atomic_set(&fs_info->scrub_cancel_req, 0);
2380         init_waitqueue_head(&fs_info->scrub_pause_wait);
2381         refcount_set(&fs_info->scrub_workers_refcnt, 0);
2382 }
2383
2384 static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2385 {
2386         spin_lock_init(&fs_info->balance_lock);
2387         mutex_init(&fs_info->balance_mutex);
2388         atomic_set(&fs_info->balance_pause_req, 0);
2389         atomic_set(&fs_info->balance_cancel_req, 0);
2390         fs_info->balance_ctl = NULL;
2391         init_waitqueue_head(&fs_info->balance_wait_q);
2392         atomic_set(&fs_info->reloc_cancel_req, 0);
2393 }
2394
2395 static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
2396 {
2397         struct inode *inode = fs_info->btree_inode;
2398
2399         inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2400         set_nlink(inode, 1);
2401         /*
2402          * we set the i_size on the btree inode to the max possible int.
2403          * the real end of the address space is determined by all of
2404          * the devices in the system
2405          */
2406         inode->i_size = OFFSET_MAX;
2407         inode->i_mapping->a_ops = &btree_aops;
2408
2409         RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
2410         extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
2411                             IO_TREE_BTREE_INODE_IO, inode);
2412         BTRFS_I(inode)->io_tree.track_uptodate = false;
2413         extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
2414
2415         BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root);
2416         memset(&BTRFS_I(inode)->location, 0, sizeof(struct btrfs_key));
2417         set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
2418         btrfs_insert_inode_hash(inode);
2419 }
2420
2421 static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2422 {
2423         mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2424         init_rwsem(&fs_info->dev_replace.rwsem);
2425         init_waitqueue_head(&fs_info->dev_replace.replace_wait);
2426 }
2427
2428 static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2429 {
2430         spin_lock_init(&fs_info->qgroup_lock);
2431         mutex_init(&fs_info->qgroup_ioctl_lock);
2432         fs_info->qgroup_tree = RB_ROOT;
2433         INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2434         fs_info->qgroup_seq = 1;
2435         fs_info->qgroup_ulist = NULL;
2436         fs_info->qgroup_rescan_running = false;
2437         mutex_init(&fs_info->qgroup_rescan_lock);
2438 }
2439
2440 static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info)
2441 {
2442         u32 max_active = fs_info->thread_pool_size;
2443         unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
2444
2445         fs_info->workers =
2446                 btrfs_alloc_workqueue(fs_info, "worker", flags, max_active, 16);
2447         fs_info->hipri_workers =
2448                 btrfs_alloc_workqueue(fs_info, "worker-high",
2449                                       flags | WQ_HIGHPRI, max_active, 16);
2450
2451         fs_info->delalloc_workers =
2452                 btrfs_alloc_workqueue(fs_info, "delalloc",
2453                                       flags, max_active, 2);
2454
2455         fs_info->flush_workers =
2456                 btrfs_alloc_workqueue(fs_info, "flush_delalloc",
2457                                       flags, max_active, 0);
2458
2459         fs_info->caching_workers =
2460                 btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
2461
2462         fs_info->fixup_workers =
2463                 btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0);
2464
2465         /*
2466          * endios are largely parallel and should have a very
2467          * low idle thresh
2468          */
2469         fs_info->endio_workers =
2470                 btrfs_alloc_workqueue(fs_info, "endio", flags, max_active, 4);
2471         fs_info->endio_meta_workers =
2472                 btrfs_alloc_workqueue(fs_info, "endio-meta", flags,
2473                                       max_active, 4);
2474         fs_info->endio_meta_write_workers =
2475                 btrfs_alloc_workqueue(fs_info, "endio-meta-write", flags,
2476                                       max_active, 2);
2477         fs_info->endio_raid56_workers =
2478                 btrfs_alloc_workqueue(fs_info, "endio-raid56", flags,
2479                                       max_active, 4);
2480         fs_info->rmw_workers = alloc_workqueue("btrfs-rmw", flags, max_active);
2481         fs_info->endio_write_workers =
2482                 btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2483                                       max_active, 2);
2484         fs_info->endio_freespace_worker =
2485                 btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2486                                       max_active, 0);
2487         fs_info->delayed_workers =
2488                 btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2489                                       max_active, 0);
2490         fs_info->qgroup_rescan_workers =
2491                 btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0);
2492         fs_info->discard_ctl.discard_workers =
2493                 alloc_workqueue("btrfs_discard", WQ_UNBOUND | WQ_FREEZABLE, 1);
2494
2495         if (!(fs_info->workers && fs_info->hipri_workers &&
2496               fs_info->delalloc_workers && fs_info->flush_workers &&
2497               fs_info->endio_workers && fs_info->endio_meta_workers &&
2498               fs_info->endio_meta_write_workers &&
2499               fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
2500               fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2501               fs_info->caching_workers && fs_info->fixup_workers &&
2502               fs_info->delayed_workers && fs_info->qgroup_rescan_workers &&
2503               fs_info->discard_ctl.discard_workers)) {
2504                 return -ENOMEM;
2505         }
2506
2507         return 0;
2508 }
2509
2510 static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2511 {
2512         struct crypto_shash *csum_shash;
2513         const char *csum_driver = btrfs_super_csum_driver(csum_type);
2514
2515         csum_shash = crypto_alloc_shash(csum_driver, 0, 0);
2516
2517         if (IS_ERR(csum_shash)) {
2518                 btrfs_err(fs_info, "error allocating %s hash for checksum",
2519                           csum_driver);
2520                 return PTR_ERR(csum_shash);
2521         }
2522
2523         fs_info->csum_shash = csum_shash;
2524
2525         return 0;
2526 }
2527
2528 static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2529                             struct btrfs_fs_devices *fs_devices)
2530 {
2531         int ret;
2532         struct btrfs_root *log_tree_root;
2533         struct btrfs_super_block *disk_super = fs_info->super_copy;
2534         u64 bytenr = btrfs_super_log_root(disk_super);
2535         int level = btrfs_super_log_root_level(disk_super);
2536
2537         if (fs_devices->rw_devices == 0) {
2538                 btrfs_warn(fs_info, "log replay required on RO media");
2539                 return -EIO;
2540         }
2541
2542         log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
2543                                          GFP_KERNEL);
2544         if (!log_tree_root)
2545                 return -ENOMEM;
2546
2547         log_tree_root->node = read_tree_block(fs_info, bytenr,
2548                                               BTRFS_TREE_LOG_OBJECTID,
2549                                               fs_info->generation + 1, level,
2550                                               NULL);
2551         if (IS_ERR(log_tree_root->node)) {
2552                 btrfs_warn(fs_info, "failed to read log tree");
2553                 ret = PTR_ERR(log_tree_root->node);
2554                 log_tree_root->node = NULL;
2555                 btrfs_put_root(log_tree_root);
2556                 return ret;
2557         }
2558         if (!extent_buffer_uptodate(log_tree_root->node)) {
2559                 btrfs_err(fs_info, "failed to read log tree");
2560                 btrfs_put_root(log_tree_root);
2561                 return -EIO;
2562         }
2563
2564         /* returns with log_tree_root freed on success */
2565         ret = btrfs_recover_log_trees(log_tree_root);
2566         if (ret) {
2567                 btrfs_handle_fs_error(fs_info, ret,
2568                                       "Failed to recover log tree");
2569                 btrfs_put_root(log_tree_root);
2570                 return ret;
2571         }
2572
2573         if (sb_rdonly(fs_info->sb)) {
2574                 ret = btrfs_commit_super(fs_info);
2575                 if (ret)
2576                         return ret;
2577         }
2578
2579         return 0;
2580 }
2581
2582 static int load_global_roots_objectid(struct btrfs_root *tree_root,
2583                                       struct btrfs_path *path, u64 objectid,
2584                                       const char *name)
2585 {
2586         struct btrfs_fs_info *fs_info = tree_root->fs_info;
2587         struct btrfs_root *root;
2588         u64 max_global_id = 0;
2589         int ret;
2590         struct btrfs_key key = {
2591                 .objectid = objectid,
2592                 .type = BTRFS_ROOT_ITEM_KEY,
2593                 .offset = 0,
2594         };
2595         bool found = false;
2596
2597         /* If we have IGNOREDATACSUMS skip loading these roots. */
2598         if (objectid == BTRFS_CSUM_TREE_OBJECTID &&
2599             btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
2600                 set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2601                 return 0;
2602         }
2603
2604         while (1) {
2605                 ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
2606                 if (ret < 0)
2607                         break;
2608
2609                 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
2610                         ret = btrfs_next_leaf(tree_root, path);
2611                         if (ret) {
2612                                 if (ret > 0)
2613                                         ret = 0;
2614                                 break;
2615                         }
2616                 }
2617                 ret = 0;
2618
2619                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2620                 if (key.objectid != objectid)
2621                         break;
2622                 btrfs_release_path(path);
2623
2624                 /*
2625                  * Just worry about this for extent tree, it'll be the same for
2626                  * everybody.
2627                  */
2628                 if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2629                         max_global_id = max(max_global_id, key.offset);
2630
2631                 found = true;
2632                 root = read_tree_root_path(tree_root, path, &key);
2633                 if (IS_ERR(root)) {
2634                         if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2635                                 ret = PTR_ERR(root);
2636                         break;
2637                 }
2638                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2639                 ret = btrfs_global_root_insert(root);
2640                 if (ret) {
2641                         btrfs_put_root(root);
2642                         break;
2643                 }
2644                 key.offset++;
2645         }
2646         btrfs_release_path(path);
2647
2648         if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2649                 fs_info->nr_global_roots = max_global_id + 1;
2650
2651         if (!found || ret) {
2652                 if (objectid == BTRFS_CSUM_TREE_OBJECTID)
2653                         set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2654
2655                 if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2656                         ret = ret ? ret : -ENOENT;
2657                 else
2658                         ret = 0;
2659                 btrfs_err(fs_info, "failed to load root %s", name);
2660         }
2661         return ret;
2662 }
2663
2664 static int load_global_roots(struct btrfs_root *tree_root)
2665 {
2666         struct btrfs_path *path;
2667         int ret = 0;
2668
2669         path = btrfs_alloc_path();
2670         if (!path)
2671                 return -ENOMEM;
2672
2673         ret = load_global_roots_objectid(tree_root, path,
2674                                          BTRFS_EXTENT_TREE_OBJECTID, "extent");
2675         if (ret)
2676                 goto out;
2677         ret = load_global_roots_objectid(tree_root, path,
2678                                          BTRFS_CSUM_TREE_OBJECTID, "csum");
2679         if (ret)
2680                 goto out;
2681         if (!btrfs_fs_compat_ro(tree_root->fs_info, FREE_SPACE_TREE))
2682                 goto out;
2683         ret = load_global_roots_objectid(tree_root, path,
2684                                          BTRFS_FREE_SPACE_TREE_OBJECTID,
2685                                          "free space");
2686 out:
2687         btrfs_free_path(path);
2688         return ret;
2689 }
2690
2691 static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2692 {
2693         struct btrfs_root *tree_root = fs_info->tree_root;
2694         struct btrfs_root *root;
2695         struct btrfs_key location;
2696         int ret;
2697
2698         BUG_ON(!fs_info->tree_root);
2699
2700         ret = load_global_roots(tree_root);
2701         if (ret)
2702                 return ret;
2703
2704         location.objectid = BTRFS_DEV_TREE_OBJECTID;
2705         location.type = BTRFS_ROOT_ITEM_KEY;
2706         location.offset = 0;
2707
2708         root = btrfs_read_tree_root(tree_root, &location);
2709         if (IS_ERR(root)) {
2710                 if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2711                         ret = PTR_ERR(root);
2712                         goto out;
2713                 }
2714         } else {
2715                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2716                 fs_info->dev_root = root;
2717         }
2718         /* Initialize fs_info for all devices in any case */
2719         btrfs_init_devices_late(fs_info);
2720
2721         /*
2722          * This tree can share blocks with some other fs tree during relocation
2723          * and we need a proper setup by btrfs_get_fs_root
2724          */
2725         root = btrfs_get_fs_root(tree_root->fs_info,
2726                                  BTRFS_DATA_RELOC_TREE_OBJECTID, true);
2727         if (IS_ERR(root)) {
2728                 if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2729                         ret = PTR_ERR(root);
2730                         goto out;
2731                 }
2732         } else {
2733                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2734                 fs_info->data_reloc_root = root;
2735         }
2736
2737         location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2738         root = btrfs_read_tree_root(tree_root, &location);
2739         if (!IS_ERR(root)) {
2740                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2741                 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
2742                 fs_info->quota_root = root;
2743         }
2744
2745         location.objectid = BTRFS_UUID_TREE_OBJECTID;
2746         root = btrfs_read_tree_root(tree_root, &location);
2747         if (IS_ERR(root)) {
2748                 if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2749                         ret = PTR_ERR(root);
2750                         if (ret != -ENOENT)
2751                                 goto out;
2752                 }
2753         } else {
2754                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2755                 fs_info->uuid_root = root;
2756         }
2757
2758         return 0;
2759 out:
2760         btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2761                    location.objectid, ret);
2762         return ret;
2763 }
2764
2765 /*
2766  * Real super block validation
2767  * NOTE: super csum type and incompat features will not be checked here.
2768  *
2769  * @sb:         super block to check
2770  * @mirror_num: the super block number to check its bytenr:
2771  *              0       the primary (1st) sb
2772  *              1, 2    2nd and 3rd backup copy
2773  *             -1       skip bytenr check
2774  */
2775 static int validate_super(struct btrfs_fs_info *fs_info,
2776                             struct btrfs_super_block *sb, int mirror_num)
2777 {
2778         u64 nodesize = btrfs_super_nodesize(sb);
2779         u64 sectorsize = btrfs_super_sectorsize(sb);
2780         int ret = 0;
2781
2782         if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2783                 btrfs_err(fs_info, "no valid FS found");
2784                 ret = -EINVAL;
2785         }
2786         if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2787                 btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2788                                 btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2789                 ret = -EINVAL;
2790         }
2791         if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2792                 btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2793                                 btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2794                 ret = -EINVAL;
2795         }
2796         if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2797                 btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2798                                 btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2799                 ret = -EINVAL;
2800         }
2801         if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2802                 btrfs_err(fs_info, "log_root level too big: %d >= %d",
2803                                 btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2804                 ret = -EINVAL;
2805         }
2806
2807         /*
2808          * Check sectorsize and nodesize first, other check will need it.
2809          * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2810          */
2811         if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2812             sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2813                 btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2814                 ret = -EINVAL;
2815         }
2816
2817         /*
2818          * We only support at most two sectorsizes: 4K and PAGE_SIZE.
2819          *
2820          * We can support 16K sectorsize with 64K page size without problem,
2821          * but such sectorsize/pagesize combination doesn't make much sense.
2822          * 4K will be our future standard, PAGE_SIZE is supported from the very
2823          * beginning.
2824          */
2825         if (sectorsize > PAGE_SIZE || (sectorsize != SZ_4K && sectorsize != PAGE_SIZE)) {
2826                 btrfs_err(fs_info,
2827                         "sectorsize %llu not yet supported for page size %lu",
2828                         sectorsize, PAGE_SIZE);
2829                 ret = -EINVAL;
2830         }
2831
2832         if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2833             nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2834                 btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2835                 ret = -EINVAL;
2836         }
2837         if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2838                 btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2839                           le32_to_cpu(sb->__unused_leafsize), nodesize);
2840                 ret = -EINVAL;
2841         }
2842
2843         /* Root alignment check */
2844         if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2845                 btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2846                            btrfs_super_root(sb));
2847                 ret = -EINVAL;
2848         }
2849         if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2850                 btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2851                            btrfs_super_chunk_root(sb));
2852                 ret = -EINVAL;
2853         }
2854         if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2855                 btrfs_warn(fs_info, "log_root block unaligned: %llu",
2856                            btrfs_super_log_root(sb));
2857                 ret = -EINVAL;
2858         }
2859
2860         if (memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid,
2861                    BTRFS_FSID_SIZE)) {
2862                 btrfs_err(fs_info,
2863                 "superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
2864                         fs_info->super_copy->fsid, fs_info->fs_devices->fsid);
2865                 ret = -EINVAL;
2866         }
2867
2868         if (btrfs_fs_incompat(fs_info, METADATA_UUID) &&
2869             memcmp(fs_info->fs_devices->metadata_uuid,
2870                    fs_info->super_copy->metadata_uuid, BTRFS_FSID_SIZE)) {
2871                 btrfs_err(fs_info,
2872 "superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU",
2873                         fs_info->super_copy->metadata_uuid,
2874                         fs_info->fs_devices->metadata_uuid);
2875                 ret = -EINVAL;
2876         }
2877
2878         if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2879                    BTRFS_FSID_SIZE) != 0) {
2880                 btrfs_err(fs_info,
2881                         "dev_item UUID does not match metadata fsid: %pU != %pU",
2882                         fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2883                 ret = -EINVAL;
2884         }
2885
2886         /*
2887          * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2888          * done later
2889          */
2890         if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2891                 btrfs_err(fs_info, "bytes_used is too small %llu",
2892                           btrfs_super_bytes_used(sb));
2893                 ret = -EINVAL;
2894         }
2895         if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2896                 btrfs_err(fs_info, "invalid stripesize %u",
2897                           btrfs_super_stripesize(sb));
2898                 ret = -EINVAL;
2899         }
2900         if (btrfs_super_num_devices(sb) > (1UL << 31))
2901                 btrfs_warn(fs_info, "suspicious number of devices: %llu",
2902                            btrfs_super_num_devices(sb));
2903         if (btrfs_super_num_devices(sb) == 0) {
2904                 btrfs_err(fs_info, "number of devices is 0");
2905                 ret = -EINVAL;
2906         }
2907
2908         if (mirror_num >= 0 &&
2909             btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2910                 btrfs_err(fs_info, "super offset mismatch %llu != %u",
2911                           btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2912                 ret = -EINVAL;
2913         }
2914
2915         /*
2916          * Obvious sys_chunk_array corruptions, it must hold at least one key
2917          * and one chunk
2918          */
2919         if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2920                 btrfs_err(fs_info, "system chunk array too big %u > %u",
2921                           btrfs_super_sys_array_size(sb),
2922                           BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2923                 ret = -EINVAL;
2924         }
2925         if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2926                         + sizeof(struct btrfs_chunk)) {
2927                 btrfs_err(fs_info, "system chunk array too small %u < %zu",
2928                           btrfs_super_sys_array_size(sb),
2929                           sizeof(struct btrfs_disk_key)
2930                           + sizeof(struct btrfs_chunk));
2931                 ret = -EINVAL;
2932         }
2933
2934         /*
2935          * The generation is a global counter, we'll trust it more than the others
2936          * but it's still possible that it's the one that's wrong.
2937          */
2938         if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2939                 btrfs_warn(fs_info,
2940                         "suspicious: generation < chunk_root_generation: %llu < %llu",
2941                         btrfs_super_generation(sb),
2942                         btrfs_super_chunk_root_generation(sb));
2943         if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2944             && btrfs_super_cache_generation(sb) != (u64)-1)
2945                 btrfs_warn(fs_info,
2946                         "suspicious: generation < cache_generation: %llu < %llu",
2947                         btrfs_super_generation(sb),
2948                         btrfs_super_cache_generation(sb));
2949
2950         return ret;
2951 }
2952
2953 /*
2954  * Validation of super block at mount time.
2955  * Some checks already done early at mount time, like csum type and incompat
2956  * flags will be skipped.
2957  */
2958 static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2959 {
2960         return validate_super(fs_info, fs_info->super_copy, 0);
2961 }
2962
2963 /*
2964  * Validation of super block at write time.
2965  * Some checks like bytenr check will be skipped as their values will be
2966  * overwritten soon.
2967  * Extra checks like csum type and incompat flags will be done here.
2968  */
2969 static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2970                                       struct btrfs_super_block *sb)
2971 {
2972         int ret;
2973
2974         ret = validate_super(fs_info, sb, -1);
2975         if (ret < 0)
2976                 goto out;
2977         if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2978                 ret = -EUCLEAN;
2979                 btrfs_err(fs_info, "invalid csum type, has %u want %u",
2980                           btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2981                 goto out;
2982         }
2983         if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2984                 ret = -EUCLEAN;
2985                 btrfs_err(fs_info,
2986                 "invalid incompat flags, has 0x%llx valid mask 0x%llx",
2987                           btrfs_super_incompat_flags(sb),
2988                           (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2989                 goto out;
2990         }
2991 out:
2992         if (ret < 0)
2993                 btrfs_err(fs_info,
2994                 "super block corruption detected before writing it to disk");
2995         return ret;
2996 }
2997
2998 static int load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int level)
2999 {
3000         int ret = 0;
3001
3002         root->node = read_tree_block(root->fs_info, bytenr,
3003                                      root->root_key.objectid, gen, level, NULL);
3004         if (IS_ERR(root->node)) {
3005                 ret = PTR_ERR(root->node);
3006                 root->node = NULL;
3007                 return ret;
3008         }
3009         if (!extent_buffer_uptodate(root->node)) {
3010                 free_extent_buffer(root->node);
3011                 root->node = NULL;
3012                 return -EIO;
3013         }
3014
3015         btrfs_set_root_node(&root->root_item, root->node);
3016         root->commit_root = btrfs_root_node(root);
3017         btrfs_set_root_refs(&root->root_item, 1);
3018         return ret;
3019 }
3020
3021 static int load_important_roots(struct btrfs_fs_info *fs_info)
3022 {
3023         struct btrfs_super_block *sb = fs_info->super_copy;
3024         u64 gen, bytenr;
3025         int level, ret;
3026
3027         bytenr = btrfs_super_root(sb);
3028         gen = btrfs_super_generation(sb);
3029         level = btrfs_super_root_level(sb);
3030         ret = load_super_root(fs_info->tree_root, bytenr, gen, level);
3031         if (ret) {
3032                 btrfs_warn(fs_info, "couldn't read tree root");
3033                 return ret;
3034         }
3035
3036         if (!btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
3037                 return 0;
3038
3039         bytenr = btrfs_super_block_group_root(sb);
3040         gen = btrfs_super_block_group_root_generation(sb);
3041         level = btrfs_super_block_group_root_level(sb);
3042         ret = load_super_root(fs_info->block_group_root, bytenr, gen, level);
3043         if (ret)
3044                 btrfs_warn(fs_info, "couldn't read block group root");
3045         return ret;
3046 }
3047
3048 static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
3049 {
3050         int backup_index = find_newest_super_backup(fs_info);
3051         struct btrfs_super_block *sb = fs_info->super_copy;
3052         struct btrfs_root *tree_root = fs_info->tree_root;
3053         bool handle_error = false;
3054         int ret = 0;
3055         int i;
3056
3057         if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
3058                 struct btrfs_root *root;
3059
3060                 root = btrfs_alloc_root(fs_info, BTRFS_BLOCK_GROUP_TREE_OBJECTID,
3061                                         GFP_KERNEL);
3062                 if (!root)
3063                         return -ENOMEM;
3064                 fs_info->block_group_root = root;
3065         }
3066
3067         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
3068                 if (handle_error) {
3069                         if (!IS_ERR(tree_root->node))
3070                                 free_extent_buffer(tree_root->node);
3071                         tree_root->node = NULL;
3072
3073                         if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
3074                                 break;
3075
3076                         free_root_pointers(fs_info, 0);
3077
3078                         /*
3079                          * Don't use the log in recovery mode, it won't be
3080                          * valid
3081                          */
3082                         btrfs_set_super_log_root(sb, 0);
3083
3084                         /* We can't trust the free space cache either */
3085                         btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
3086
3087                         ret = read_backup_root(fs_info, i);
3088                         backup_index = ret;
3089                         if (ret < 0)
3090                                 return ret;
3091                 }
3092
3093                 ret = load_important_roots(fs_info);
3094                 if (ret) {
3095                         handle_error = true;
3096                         continue;
3097                 }
3098
3099                 /*
3100                  * No need to hold btrfs_root::objectid_mutex since the fs
3101                  * hasn't been fully initialised and we are the only user
3102                  */
3103                 ret = btrfs_init_root_free_objectid(tree_root);
3104                 if (ret < 0) {
3105                         handle_error = true;
3106                         continue;
3107                 }
3108
3109                 ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
3110
3111                 ret = btrfs_read_roots(fs_info);
3112                 if (ret < 0) {
3113                         handle_error = true;
3114                         continue;
3115                 }
3116
3117                 /* All successful */
3118                 fs_info->generation = btrfs_header_generation(tree_root->node);
3119                 fs_info->last_trans_committed = fs_info->generation;
3120                 fs_info->last_reloc_trans = 0;
3121
3122                 /* Always begin writing backup roots after the one being used */
3123                 if (backup_index < 0) {
3124                         fs_info->backup_root_index = 0;
3125                 } else {
3126                         fs_info->backup_root_index = backup_index + 1;
3127                         fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS;
3128                 }
3129                 break;
3130         }
3131
3132         return ret;
3133 }
3134
3135 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
3136 {
3137         xa_init_flags(&fs_info->fs_roots, GFP_ATOMIC);
3138         xa_init_flags(&fs_info->extent_buffers, GFP_ATOMIC);
3139         INIT_LIST_HEAD(&fs_info->trans_list);
3140         INIT_LIST_HEAD(&fs_info->dead_roots);
3141         INIT_LIST_HEAD(&fs_info->delayed_iputs);
3142         INIT_LIST_HEAD(&fs_info->delalloc_roots);
3143         INIT_LIST_HEAD(&fs_info->caching_block_groups);
3144         spin_lock_init(&fs_info->delalloc_root_lock);
3145         spin_lock_init(&fs_info->trans_lock);
3146         spin_lock_init(&fs_info->fs_roots_lock);
3147         spin_lock_init(&fs_info->delayed_iput_lock);
3148         spin_lock_init(&fs_info->defrag_inodes_lock);
3149         spin_lock_init(&fs_info->super_lock);
3150         spin_lock_init(&fs_info->buffer_lock);
3151         spin_lock_init(&fs_info->unused_bgs_lock);
3152         spin_lock_init(&fs_info->treelog_bg_lock);
3153         spin_lock_init(&fs_info->zone_active_bgs_lock);
3154         spin_lock_init(&fs_info->relocation_bg_lock);
3155         rwlock_init(&fs_info->tree_mod_log_lock);
3156         rwlock_init(&fs_info->global_root_lock);
3157         mutex_init(&fs_info->unused_bg_unpin_mutex);
3158         mutex_init(&fs_info->reclaim_bgs_lock);
3159         mutex_init(&fs_info->reloc_mutex);
3160         mutex_init(&fs_info->delalloc_root_mutex);
3161         mutex_init(&fs_info->zoned_meta_io_lock);
3162         mutex_init(&fs_info->zoned_data_reloc_io_lock);
3163         seqlock_init(&fs_info->profiles_lock);
3164
3165         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
3166         INIT_LIST_HEAD(&fs_info->space_info);
3167         INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
3168         INIT_LIST_HEAD(&fs_info->unused_bgs);
3169         INIT_LIST_HEAD(&fs_info->reclaim_bgs);
3170         INIT_LIST_HEAD(&fs_info->zone_active_bgs);
3171 #ifdef CONFIG_BTRFS_DEBUG
3172         INIT_LIST_HEAD(&fs_info->allocated_roots);
3173         INIT_LIST_HEAD(&fs_info->allocated_ebs);
3174         spin_lock_init(&fs_info->eb_leak_lock);
3175 #endif
3176         extent_map_tree_init(&fs_info->mapping_tree);
3177         btrfs_init_block_rsv(&fs_info->global_block_rsv,
3178                              BTRFS_BLOCK_RSV_GLOBAL);
3179         btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
3180         btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
3181         btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
3182         btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
3183                              BTRFS_BLOCK_RSV_DELOPS);
3184         btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
3185                              BTRFS_BLOCK_RSV_DELREFS);
3186
3187         atomic_set(&fs_info->async_delalloc_pages, 0);
3188         atomic_set(&fs_info->defrag_running, 0);
3189         atomic_set(&fs_info->nr_delayed_iputs, 0);
3190         atomic64_set(&fs_info->tree_mod_seq, 0);
3191         fs_info->global_root_tree = RB_ROOT;
3192         fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
3193         fs_info->metadata_ratio = 0;
3194         fs_info->defrag_inodes = RB_ROOT;
3195         atomic64_set(&fs_info->free_chunk_space, 0);
3196         fs_info->tree_mod_log = RB_ROOT;
3197         fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
3198         fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
3199         btrfs_init_ref_verify(fs_info);
3200
3201         fs_info->thread_pool_size = min_t(unsigned long,
3202                                           num_online_cpus() + 2, 8);
3203
3204         INIT_LIST_HEAD(&fs_info->ordered_roots);
3205         spin_lock_init(&fs_info->ordered_root_lock);
3206
3207         btrfs_init_scrub(fs_info);
3208 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3209         fs_info->check_integrity_print_mask = 0;
3210 #endif
3211         btrfs_init_balance(fs_info);
3212         btrfs_init_async_reclaim_work(fs_info);
3213
3214         rwlock_init(&fs_info->block_group_cache_lock);
3215         fs_info->block_group_cache_tree = RB_ROOT_CACHED;
3216
3217         extent_io_tree_init(fs_info, &fs_info->excluded_extents,
3218                             IO_TREE_FS_EXCLUDED_EXTENTS, NULL);
3219
3220         mutex_init(&fs_info->ordered_operations_mutex);
3221         mutex_init(&fs_info->tree_log_mutex);
3222         mutex_init(&fs_info->chunk_mutex);
3223         mutex_init(&fs_info->transaction_kthread_mutex);
3224         mutex_init(&fs_info->cleaner_mutex);
3225         mutex_init(&fs_info->ro_block_group_mutex);
3226         init_rwsem(&fs_info->commit_root_sem);
3227         init_rwsem(&fs_info->cleanup_work_sem);
3228         init_rwsem(&fs_info->subvol_sem);
3229         sema_init(&fs_info->uuid_tree_rescan_sem, 1);
3230
3231         btrfs_init_dev_replace_locks(fs_info);
3232         btrfs_init_qgroup(fs_info);
3233         btrfs_discard_init(fs_info);
3234
3235         btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
3236         btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
3237
3238         init_waitqueue_head(&fs_info->transaction_throttle);
3239         init_waitqueue_head(&fs_info->transaction_wait);
3240         init_waitqueue_head(&fs_info->transaction_blocked_wait);
3241         init_waitqueue_head(&fs_info->async_submit_wait);
3242         init_waitqueue_head(&fs_info->delayed_iputs_wait);
3243
3244         /* Usable values until the real ones are cached from the superblock */
3245         fs_info->nodesize = 4096;
3246         fs_info->sectorsize = 4096;
3247         fs_info->sectorsize_bits = ilog2(4096);
3248         fs_info->stripesize = 4096;
3249
3250         spin_lock_init(&fs_info->swapfile_pins_lock);
3251         fs_info->swapfile_pins = RB_ROOT;
3252
3253         fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
3254         INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
3255 }
3256
3257 static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
3258 {
3259         int ret;
3260
3261         fs_info->sb = sb;
3262         sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
3263         sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
3264
3265         ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
3266         if (ret)
3267                 return ret;
3268
3269         ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
3270         if (ret)
3271                 return ret;
3272
3273         fs_info->dirty_metadata_batch = PAGE_SIZE *
3274                                         (1 + ilog2(nr_cpu_ids));
3275
3276         ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
3277         if (ret)
3278                 return ret;
3279
3280         ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
3281                         GFP_KERNEL);
3282         if (ret)
3283                 return ret;
3284
3285         fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
3286                                         GFP_KERNEL);
3287         if (!fs_info->delayed_root)
3288                 return -ENOMEM;
3289         btrfs_init_delayed_root(fs_info->delayed_root);
3290
3291         if (sb_rdonly(sb))
3292                 set_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state);
3293
3294         return btrfs_alloc_stripe_hash_table(fs_info);
3295 }
3296
3297 static int btrfs_uuid_rescan_kthread(void *data)
3298 {
3299         struct btrfs_fs_info *fs_info = data;
3300         int ret;
3301
3302         /*
3303          * 1st step is to iterate through the existing UUID tree and
3304          * to delete all entries that contain outdated data.
3305          * 2nd step is to add all missing entries to the UUID tree.
3306          */
3307         ret = btrfs_uuid_tree_iterate(fs_info);
3308         if (ret < 0) {
3309                 if (ret != -EINTR)
3310                         btrfs_warn(fs_info, "iterating uuid_tree failed %d",
3311                                    ret);
3312                 up(&fs_info->uuid_tree_rescan_sem);
3313                 return ret;
3314         }
3315         return btrfs_uuid_scan_kthread(data);
3316 }
3317
3318 static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3319 {
3320         struct task_struct *task;
3321
3322         down(&fs_info->uuid_tree_rescan_sem);
3323         task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3324         if (IS_ERR(task)) {
3325                 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3326                 btrfs_warn(fs_info, "failed to start uuid_rescan task");
3327                 up(&fs_info->uuid_tree_rescan_sem);
3328                 return PTR_ERR(task);
3329         }
3330
3331         return 0;
3332 }
3333
3334 /*
3335  * Some options only have meaning at mount time and shouldn't persist across
3336  * remounts, or be displayed. Clear these at the end of mount and remount
3337  * code paths.
3338  */
3339 void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info)
3340 {
3341         btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3342         btrfs_clear_opt(fs_info->mount_opt, CLEAR_CACHE);
3343 }
3344
3345 /*
3346  * Mounting logic specific to read-write file systems. Shared by open_ctree
3347  * and btrfs_remount when remounting from read-only to read-write.
3348  */
3349 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
3350 {
3351         int ret;
3352         const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
3353         bool clear_free_space_tree = false;
3354
3355         if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3356             btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3357                 clear_free_space_tree = true;
3358         } else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3359                    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3360                 btrfs_warn(fs_info, "free space tree is invalid");
3361                 clear_free_space_tree = true;
3362         }
3363
3364         if (clear_free_space_tree) {
3365                 btrfs_info(fs_info, "clearing free space tree");
3366                 ret = btrfs_clear_free_space_tree(fs_info);
3367                 if (ret) {
3368                         btrfs_warn(fs_info,
3369                                    "failed to clear free space tree: %d", ret);
3370                         goto out;
3371                 }
3372         }
3373
3374         /*
3375          * btrfs_find_orphan_roots() is responsible for finding all the dead
3376          * roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
3377          * them into the fs_info->fs_roots. This must be done before
3378          * calling btrfs_orphan_cleanup() on the tree root. If we don't do it
3379          * first, then btrfs_orphan_cleanup() will delete a dead root's orphan
3380          * item before the root's tree is deleted - this means that if we unmount
3381          * or crash before the deletion completes, on the next mount we will not
3382          * delete what remains of the tree because the orphan item does not
3383          * exists anymore, which is what tells us we have a pending deletion.
3384          */
3385         ret = btrfs_find_orphan_roots(fs_info);
3386         if (ret)
3387                 goto out;
3388
3389         ret = btrfs_cleanup_fs_roots(fs_info);
3390         if (ret)
3391                 goto out;
3392
3393         down_read(&fs_info->cleanup_work_sem);
3394         if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3395             (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3396                 up_read(&fs_info->cleanup_work_sem);
3397                 goto out;
3398         }
3399         up_read(&fs_info->cleanup_work_sem);
3400
3401         mutex_lock(&fs_info->cleaner_mutex);
3402         ret = btrfs_recover_relocation(fs_info);
3403         mutex_unlock(&fs_info->cleaner_mutex);
3404         if (ret < 0) {
3405                 btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
3406                 goto out;
3407         }
3408
3409         if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3410             !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3411                 btrfs_info(fs_info, "creating free space tree");
3412                 ret = btrfs_create_free_space_tree(fs_info);
3413                 if (ret) {
3414                         btrfs_warn(fs_info,
3415                                 "failed to create free space tree: %d", ret);
3416                         goto out;
3417                 }
3418         }
3419
3420         if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
3421                 ret = btrfs_set_free_space_cache_v1_active(fs_info, cache_opt);
3422                 if (ret)
3423                         goto out;
3424         }
3425
3426         ret = btrfs_resume_balance_async(fs_info);
3427         if (ret)
3428                 goto out;
3429
3430         ret = btrfs_resume_dev_replace_async(fs_info);
3431         if (ret) {
3432                 btrfs_warn(fs_info, "failed to resume dev_replace");
3433                 goto out;
3434         }
3435
3436         btrfs_qgroup_rescan_resume(fs_info);
3437
3438         if (!fs_info->uuid_root) {
3439                 btrfs_info(fs_info, "creating UUID tree");
3440                 ret = btrfs_create_uuid_tree(fs_info);
3441                 if (ret) {
3442                         btrfs_warn(fs_info,
3443                                    "failed to create the UUID tree %d", ret);
3444                         goto out;
3445                 }
3446         }
3447
3448 out:
3449         return ret;
3450 }
3451
3452 int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
3453                       char *options)
3454 {
3455         u32 sectorsize;
3456         u32 nodesize;
3457         u32 stripesize;
3458         u64 generation;
3459         u64 features;
3460         u16 csum_type;
3461         struct btrfs_super_block *disk_super;
3462         struct btrfs_fs_info *fs_info = btrfs_sb(sb);
3463         struct btrfs_root *tree_root;
3464         struct btrfs_root *chunk_root;
3465         int ret;
3466         int err = -EINVAL;
3467         int level;
3468
3469         ret = init_mount_fs_info(fs_info, sb);
3470         if (ret) {
3471                 err = ret;
3472                 goto fail;
3473         }
3474
3475         /* These need to be init'ed before we start creating inodes and such. */
3476         tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID,
3477                                      GFP_KERNEL);
3478         fs_info->tree_root = tree_root;
3479         chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID,
3480                                       GFP_KERNEL);
3481         fs_info->chunk_root = chunk_root;
3482         if (!tree_root || !chunk_root) {
3483                 err = -ENOMEM;
3484                 goto fail;
3485         }
3486
3487         fs_info->btree_inode = new_inode(sb);
3488         if (!fs_info->btree_inode) {
3489                 err = -ENOMEM;
3490                 goto fail;
3491         }
3492         mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
3493         btrfs_init_btree_inode(fs_info);
3494
3495         invalidate_bdev(fs_devices->latest_dev->bdev);
3496
3497         /*
3498          * Read super block and check the signature bytes only
3499          */
3500         disk_super = btrfs_read_dev_super(fs_devices->latest_dev->bdev);
3501         if (IS_ERR(disk_super)) {
3502                 err = PTR_ERR(disk_super);
3503                 goto fail_alloc;
3504         }
3505
3506         /*
3507          * Verify the type first, if that or the checksum value are
3508          * corrupted, we'll find out
3509          */
3510         csum_type = btrfs_super_csum_type(disk_super);
3511         if (!btrfs_supported_super_csum(csum_type)) {
3512                 btrfs_err(fs_info, "unsupported checksum algorithm: %u",
3513                           csum_type);
3514                 err = -EINVAL;
3515                 btrfs_release_disk_super(disk_super);
3516                 goto fail_alloc;
3517         }
3518
3519         fs_info->csum_size = btrfs_super_csum_size(disk_super);
3520
3521         ret = btrfs_init_csum_hash(fs_info, csum_type);
3522         if (ret) {
3523                 err = ret;
3524                 btrfs_release_disk_super(disk_super);
3525                 goto fail_alloc;
3526         }
3527
3528         /*
3529          * We want to check superblock checksum, the type is stored inside.
3530          * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
3531          */
3532         if (btrfs_check_super_csum(fs_info, (u8 *)disk_super)) {
3533                 btrfs_err(fs_info, "superblock checksum mismatch");
3534                 err = -EINVAL;
3535                 btrfs_release_disk_super(disk_super);
3536                 goto fail_alloc;
3537         }
3538
3539         /*
3540          * super_copy is zeroed at allocation time and we never touch the
3541          * following bytes up to INFO_SIZE, the checksum is calculated from
3542          * the whole block of INFO_SIZE
3543          */
3544         memcpy(fs_info->super_copy, disk_super, sizeof(*fs_info->super_copy));
3545         btrfs_release_disk_super(disk_super);
3546
3547         disk_super = fs_info->super_copy;
3548
3549
3550         features = btrfs_super_flags(disk_super);
3551         if (features & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
3552                 features &= ~BTRFS_SUPER_FLAG_CHANGING_FSID_V2;
3553                 btrfs_set_super_flags(disk_super, features);
3554                 btrfs_info(fs_info,
3555                         "found metadata UUID change in progress flag, clearing");
3556         }
3557
3558         memcpy(fs_info->super_for_commit, fs_info->super_copy,
3559                sizeof(*fs_info->super_for_commit));
3560
3561         ret = btrfs_validate_mount_super(fs_info);
3562         if (ret) {
3563                 btrfs_err(fs_info, "superblock contains fatal errors");
3564                 err = -EINVAL;
3565                 goto fail_alloc;
3566         }
3567
3568         if (!btrfs_super_root(disk_super))
3569                 goto fail_alloc;
3570
3571         /* check FS state, whether FS is broken. */
3572         if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
3573                 set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
3574
3575         /*
3576          * In the long term, we'll store the compression type in the super
3577          * block, and it'll be used for per file compression control.
3578          */
3579         fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
3580
3581         /*
3582          * Flag our filesystem as having big metadata blocks if they are bigger
3583          * than the page size.
3584          */
3585         if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
3586                 if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
3587                         btrfs_info(fs_info,
3588                                 "flagging fs with big metadata feature");
3589                 features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
3590         }
3591
3592         /* Set up fs_info before parsing mount options */
3593         nodesize = btrfs_super_nodesize(disk_super);
3594         sectorsize = btrfs_super_sectorsize(disk_super);
3595         stripesize = sectorsize;
3596         fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
3597         fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
3598
3599         fs_info->nodesize = nodesize;
3600         fs_info->sectorsize = sectorsize;
3601         fs_info->sectorsize_bits = ilog2(sectorsize);
3602         fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
3603         fs_info->stripesize = stripesize;
3604
3605         ret = btrfs_parse_options(fs_info, options, sb->s_flags);
3606         if (ret) {
3607                 err = ret;
3608                 goto fail_alloc;
3609         }
3610
3611         features = btrfs_super_incompat_flags(disk_super) &
3612                 ~BTRFS_FEATURE_INCOMPAT_SUPP;
3613         if (features) {
3614                 btrfs_err(fs_info,
3615                     "cannot mount because of unsupported optional features (0x%llx)",
3616                     features);
3617                 err = -EINVAL;
3618                 goto fail_alloc;
3619         }
3620
3621         features = btrfs_super_incompat_flags(disk_super);
3622         features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
3623         if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
3624                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
3625         else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
3626                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
3627
3628         if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
3629                 btrfs_info(fs_info, "has skinny extents");
3630
3631         /*
3632          * mixed block groups end up with duplicate but slightly offset
3633          * extent buffers for the same range.  It leads to corruptions
3634          */
3635         if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
3636             (sectorsize != nodesize)) {
3637                 btrfs_err(fs_info,
3638 "unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
3639                         nodesize, sectorsize);
3640                 goto fail_alloc;
3641         }
3642
3643         /*
3644          * Needn't use the lock because there is no other task which will
3645          * update the flag.
3646          */
3647         btrfs_set_super_incompat_flags(disk_super, features);
3648
3649         features = btrfs_super_compat_ro_flags(disk_super) &
3650                 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
3651         if (!sb_rdonly(sb) && features) {
3652                 btrfs_err(fs_info,
3653         "cannot mount read-write because of unsupported optional features (0x%llx)",
3654                        features);
3655                 err = -EINVAL;
3656                 goto fail_alloc;
3657         }
3658
3659         if (sectorsize < PAGE_SIZE) {
3660                 struct btrfs_subpage_info *subpage_info;
3661
3662                 /*
3663                  * V1 space cache has some hardcoded PAGE_SIZE usage, and is
3664                  * going to be deprecated.
3665                  *
3666                  * Force to use v2 cache for subpage case.
3667                  */
3668                 btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE);
3669                 btrfs_set_and_info(fs_info, FREE_SPACE_TREE,
3670                         "forcing free space tree for sector size %u with page size %lu",
3671                         sectorsize, PAGE_SIZE);
3672
3673                 btrfs_warn(fs_info,
3674                 "read-write for sector size %u with page size %lu is experimental",
3675                            sectorsize, PAGE_SIZE);
3676                 subpage_info = kzalloc(sizeof(*subpage_info), GFP_KERNEL);
3677                 if (!subpage_info)
3678                         goto fail_alloc;
3679                 btrfs_init_subpage_info(subpage_info, sectorsize);
3680                 fs_info->subpage_info = subpage_info;
3681         }
3682
3683         ret = btrfs_init_workqueues(fs_info);
3684         if (ret) {
3685                 err = ret;
3686                 goto fail_sb_buffer;
3687         }
3688
3689         sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
3690         sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
3691
3692         sb->s_blocksize = sectorsize;
3693         sb->s_blocksize_bits = blksize_bits(sectorsize);
3694         memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
3695
3696         mutex_lock(&fs_info->chunk_mutex);
3697         ret = btrfs_read_sys_array(fs_info);
3698         mutex_unlock(&fs_info->chunk_mutex);
3699         if (ret) {
3700                 btrfs_err(fs_info, "failed to read the system array: %d", ret);
3701                 goto fail_sb_buffer;
3702         }
3703
3704         generation = btrfs_super_chunk_root_generation(disk_super);
3705         level = btrfs_super_chunk_root_level(disk_super);
3706         ret = load_super_root(chunk_root, btrfs_super_chunk_root(disk_super),
3707                               generation, level);
3708         if (ret) {
3709                 btrfs_err(fs_info, "failed to read chunk root");
3710                 goto fail_tree_roots;
3711         }
3712
3713         read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3714                            offsetof(struct btrfs_header, chunk_tree_uuid),
3715                            BTRFS_UUID_SIZE);
3716
3717         ret = btrfs_read_chunk_tree(fs_info);
3718         if (ret) {
3719                 btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3720                 goto fail_tree_roots;
3721         }
3722
3723         /*
3724          * At this point we know all the devices that make this filesystem,
3725          * including the seed devices but we don't know yet if the replace
3726          * target is required. So free devices that are not part of this
3727          * filesystem but skip the replace target device which is checked
3728          * below in btrfs_init_dev_replace().
3729          */
3730         btrfs_free_extra_devids(fs_devices);
3731         if (!fs_devices->latest_dev->bdev) {
3732                 btrfs_err(fs_info, "failed to read devices");
3733                 goto fail_tree_roots;
3734         }
3735
3736         ret = init_tree_roots(fs_info);
3737         if (ret)
3738                 goto fail_tree_roots;
3739
3740         /*
3741          * Get zone type information of zoned block devices. This will also
3742          * handle emulation of a zoned filesystem if a regular device has the
3743          * zoned incompat feature flag set.
3744          */
3745         ret = btrfs_get_dev_zone_info_all_devices(fs_info);
3746         if (ret) {
3747                 btrfs_err(fs_info,
3748                           "zoned: failed to read device zone info: %d",
3749                           ret);
3750                 goto fail_block_groups;
3751         }
3752
3753         /*
3754          * If we have a uuid root and we're not being told to rescan we need to
3755          * check the generation here so we can set the
3756          * BTRFS_FS_UPDATE_UUID_TREE_GEN bit.  Otherwise we could commit the
3757          * transaction during a balance or the log replay without updating the
3758          * uuid generation, and then if we crash we would rescan the uuid tree,
3759          * even though it was perfectly fine.
3760          */
3761         if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) &&
3762             fs_info->generation == btrfs_super_uuid_tree_generation(disk_super))
3763                 set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3764
3765         ret = btrfs_verify_dev_extents(fs_info);
3766         if (ret) {
3767                 btrfs_err(fs_info,
3768                           "failed to verify dev extents against chunks: %d",
3769                           ret);
3770                 goto fail_block_groups;
3771         }
3772         ret = btrfs_recover_balance(fs_info);
3773         if (ret) {
3774                 btrfs_err(fs_info, "failed to recover balance: %d", ret);
3775                 goto fail_block_groups;
3776         }
3777
3778         ret = btrfs_init_dev_stats(fs_info);
3779         if (ret) {
3780                 btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3781                 goto fail_block_groups;
3782         }
3783
3784         ret = btrfs_init_dev_replace(fs_info);
3785         if (ret) {
3786                 btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3787                 goto fail_block_groups;
3788         }
3789
3790         ret = btrfs_check_zoned_mode(fs_info);
3791         if (ret) {
3792                 btrfs_err(fs_info, "failed to initialize zoned mode: %d",
3793                           ret);
3794                 goto fail_block_groups;
3795         }
3796
3797         ret = btrfs_sysfs_add_fsid(fs_devices);
3798         if (ret) {
3799                 btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3800                                 ret);
3801                 goto fail_block_groups;
3802         }
3803
3804         ret = btrfs_sysfs_add_mounted(fs_info);
3805         if (ret) {
3806                 btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3807                 goto fail_fsdev_sysfs;
3808         }
3809
3810         ret = btrfs_init_space_info(fs_info);
3811         if (ret) {
3812                 btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3813                 goto fail_sysfs;
3814         }
3815
3816         ret = btrfs_read_block_groups(fs_info);
3817         if (ret) {
3818                 btrfs_err(fs_info, "failed to read block groups: %d", ret);
3819                 goto fail_sysfs;
3820         }
3821
3822         btrfs_free_zone_cache(fs_info);
3823
3824         if (!sb_rdonly(sb) && fs_info->fs_devices->missing_devices &&
3825             !btrfs_check_rw_degradable(fs_info, NULL)) {
3826                 btrfs_warn(fs_info,
3827                 "writable mount is not allowed due to too many missing devices");
3828                 goto fail_sysfs;
3829         }
3830
3831         fs_info->cleaner_kthread = kthread_run(cleaner_kthread, fs_info,
3832                                                "btrfs-cleaner");
3833         if (IS_ERR(fs_info->cleaner_kthread))
3834                 goto fail_sysfs;
3835
3836         fs_info->transaction_kthread = kthread_run(transaction_kthread,
3837                                                    tree_root,
3838                                                    "btrfs-transaction");
3839         if (IS_ERR(fs_info->transaction_kthread))
3840                 goto fail_cleaner;
3841
3842         if (!btrfs_test_opt(fs_info, NOSSD) &&
3843             !fs_info->fs_devices->rotating) {
3844                 btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations");
3845         }
3846
3847         /*
3848          * Mount does not set all options immediately, we can do it now and do
3849          * not have to wait for transaction commit
3850          */
3851         btrfs_apply_pending_changes(fs_info);
3852
3853 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3854         if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) {
3855                 ret = btrfsic_mount(fs_info, fs_devices,
3856                                     btrfs_test_opt(fs_info,
3857                                         CHECK_INTEGRITY_DATA) ? 1 : 0,
3858                                     fs_info->check_integrity_print_mask);
3859                 if (ret)
3860                         btrfs_warn(fs_info,
3861                                 "failed to initialize integrity check module: %d",
3862                                 ret);
3863         }
3864 #endif
3865         ret = btrfs_read_qgroup_config(fs_info);
3866         if (ret)
3867                 goto fail_trans_kthread;
3868
3869         if (btrfs_build_ref_tree(fs_info))
3870                 btrfs_err(fs_info, "couldn't build ref tree");
3871
3872         /* do not make disk changes in broken FS or nologreplay is given */
3873         if (btrfs_super_log_root(disk_super) != 0 &&
3874             !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3875                 btrfs_info(fs_info, "start tree-log replay");
3876                 ret = btrfs_replay_log(fs_info, fs_devices);
3877                 if (ret) {
3878                         err = ret;
3879                         goto fail_qgroup;
3880                 }
3881         }
3882
3883         fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true);
3884         if (IS_ERR(fs_info->fs_root)) {
3885                 err = PTR_ERR(fs_info->fs_root);
3886                 btrfs_warn(fs_info, "failed to read fs tree: %d", err);
3887                 fs_info->fs_root = NULL;
3888                 goto fail_qgroup;
3889         }
3890
3891         if (sb_rdonly(sb))
3892                 goto clear_oneshot;
3893
3894         ret = btrfs_start_pre_rw_mount(fs_info);
3895         if (ret) {
3896                 close_ctree(fs_info);
3897                 return ret;
3898         }
3899         btrfs_discard_resume(fs_info);
3900
3901         if (fs_info->uuid_root &&
3902             (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3903              fs_info->generation != btrfs_super_uuid_tree_generation(disk_super))) {
3904                 btrfs_info(fs_info, "checking UUID tree");
3905                 ret = btrfs_check_uuid_tree(fs_info);
3906                 if (ret) {
3907                         btrfs_warn(fs_info,
3908                                 "failed to check the UUID tree: %d", ret);
3909                         close_ctree(fs_info);
3910                         return ret;
3911                 }
3912         }
3913
3914         set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3915
3916         /* Kick the cleaner thread so it'll start deleting snapshots. */
3917         if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
3918                 wake_up_process(fs_info->cleaner_kthread);
3919
3920 clear_oneshot:
3921         btrfs_clear_oneshot_options(fs_info);
3922         return 0;
3923
3924 fail_qgroup:
3925         btrfs_free_qgroup_config(fs_info);
3926 fail_trans_kthread:
3927         kthread_stop(fs_info->transaction_kthread);
3928         btrfs_cleanup_transaction(fs_info);
3929         btrfs_free_fs_roots(fs_info);
3930 fail_cleaner:
3931         kthread_stop(fs_info->cleaner_kthread);
3932
3933         /*
3934          * make sure we're done with the btree inode before we stop our
3935          * kthreads
3936          */
3937         filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3938
3939 fail_sysfs:
3940         btrfs_sysfs_remove_mounted(fs_info);
3941
3942 fail_fsdev_sysfs:
3943         btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3944
3945 fail_block_groups:
3946         btrfs_put_block_group_cache(fs_info);
3947
3948 fail_tree_roots:
3949         if (fs_info->data_reloc_root)
3950                 btrfs_drop_and_free_fs_root(fs_info, fs_info->data_reloc_root);
3951         free_root_pointers(fs_info, true);
3952         invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3953
3954 fail_sb_buffer:
3955         btrfs_stop_all_workers(fs_info);
3956         btrfs_free_block_groups(fs_info);
3957 fail_alloc:
3958         btrfs_mapping_tree_free(&fs_info->mapping_tree);
3959
3960         iput(fs_info->btree_inode);
3961 fail:
3962         btrfs_close_devices(fs_info->fs_devices);
3963         return err;
3964 }
3965 ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3966
3967 static void btrfs_end_super_write(struct bio *bio)
3968 {
3969         struct btrfs_device *device = bio->bi_private;
3970         struct bio_vec *bvec;
3971         struct bvec_iter_all iter_all;
3972         struct page *page;
3973
3974         bio_for_each_segment_all(bvec, bio, iter_all) {
3975                 page = bvec->bv_page;
3976
3977                 if (bio->bi_status) {
3978                         btrfs_warn_rl_in_rcu(device->fs_info,
3979                                 "lost page write due to IO error on %s (%d)",
3980                                 rcu_str_deref(device->name),
3981                                 blk_status_to_errno(bio->bi_status));
3982                         ClearPageUptodate(page);
3983                         SetPageError(page);
3984                         btrfs_dev_stat_inc_and_print(device,
3985                                                      BTRFS_DEV_STAT_WRITE_ERRS);
3986                 } else {
3987                         SetPageUptodate(page);
3988                 }
3989
3990                 put_page(page);
3991                 unlock_page(page);
3992         }
3993
3994         bio_put(bio);
3995 }
3996
3997 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
3998                                                    int copy_num)
3999 {
4000         struct btrfs_super_block *super;
4001         struct page *page;
4002         u64 bytenr, bytenr_orig;
4003         struct address_space *mapping = bdev->bd_inode->i_mapping;
4004         int ret;
4005
4006         bytenr_orig = btrfs_sb_offset(copy_num);
4007         ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
4008         if (ret == -ENOENT)
4009                 return ERR_PTR(-EINVAL);
4010         else if (ret)
4011                 return ERR_PTR(ret);
4012
4013         if (bytenr + BTRFS_SUPER_INFO_SIZE >= bdev_nr_bytes(bdev))
4014                 return ERR_PTR(-EINVAL);
4015
4016         page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS);
4017         if (IS_ERR(page))
4018                 return ERR_CAST(page);
4019
4020         super = page_address(page);
4021         if (btrfs_super_magic(super) != BTRFS_MAGIC) {
4022                 btrfs_release_disk_super(super);
4023                 return ERR_PTR(-ENODATA);
4024         }
4025
4026         if (btrfs_super_bytenr(super) != bytenr_orig) {
4027                 btrfs_release_disk_super(super);
4028                 return ERR_PTR(-EINVAL);
4029         }
4030
4031         return super;
4032 }
4033
4034
4035 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev)
4036 {
4037         struct btrfs_super_block *super, *latest = NULL;
4038         int i;
4039         u64 transid = 0;
4040
4041         /* we would like to check all the supers, but that would make
4042          * a btrfs mount succeed after a mkfs from a different FS.
4043          * So, we need to add a special mount option to scan for
4044          * later supers, using BTRFS_SUPER_MIRROR_MAX instead
4045          */
4046         for (i = 0; i < 1; i++) {
4047                 super = btrfs_read_dev_one_super(bdev, i);
4048                 if (IS_ERR(super))
4049                         continue;
4050
4051                 if (!latest || btrfs_super_generation(super) > transid) {
4052                         if (latest)
4053                                 btrfs_release_disk_super(super);
4054
4055                         latest = super;
4056                         transid = btrfs_super_generation(super);
4057                 }
4058         }
4059
4060         return super;
4061 }
4062
4063 /*
4064  * Write superblock @sb to the @device. Do not wait for completion, all the
4065  * pages we use for writing are locked.
4066  *
4067  * Write @max_mirrors copies of the superblock, where 0 means default that fit
4068  * the expected device size at commit time. Note that max_mirrors must be
4069  * same for write and wait phases.
4070  *
4071  * Return number of errors when page is not found or submission fails.
4072  */
4073 static int write_dev_supers(struct btrfs_device *device,
4074                             struct btrfs_super_block *sb, int max_mirrors)
4075 {
4076         struct btrfs_fs_info *fs_info = device->fs_info;
4077         struct address_space *mapping = device->bdev->bd_inode->i_mapping;
4078         SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
4079         int i;
4080         int errors = 0;
4081         int ret;
4082         u64 bytenr, bytenr_orig;
4083
4084         if (max_mirrors == 0)
4085                 max_mirrors = BTRFS_SUPER_MIRROR_MAX;
4086
4087         shash->tfm = fs_info->csum_shash;
4088
4089         for (i = 0; i < max_mirrors; i++) {
4090                 struct page *page;
4091                 struct bio *bio;
4092                 struct btrfs_super_block *disk_super;
4093
4094                 bytenr_orig = btrfs_sb_offset(i);
4095                 ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
4096                 if (ret == -ENOENT) {
4097                         continue;
4098                 } else if (ret < 0) {
4099                         btrfs_err(device->fs_info,
4100                                 "couldn't get super block location for mirror %d",
4101                                 i);
4102                         errors++;
4103                         continue;
4104                 }
4105                 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
4106                     device->commit_total_bytes)
4107                         break;
4108
4109                 btrfs_set_super_bytenr(sb, bytenr_orig);
4110
4111                 crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
4112                                     BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
4113                                     sb->csum);
4114
4115                 page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT,
4116                                            GFP_NOFS);
4117                 if (!page) {
4118                         btrfs_err(device->fs_info,
4119                             "couldn't get super block page for bytenr %llu",
4120                             bytenr);
4121                         errors++;
4122                         continue;
4123                 }
4124
4125                 /* Bump the refcount for wait_dev_supers() */
4126                 get_page(page);
4127
4128                 disk_super = page_address(page);
4129                 memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE);
4130
4131                 /*
4132                  * Directly use bios here instead of relying on the page cache
4133                  * to do I/O, so we don't lose the ability to do integrity
4134                  * checking.
4135                  */
4136                 bio = bio_alloc(device->bdev, 1,
4137                                 REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO,
4138                                 GFP_NOFS);
4139                 bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
4140                 bio->bi_private = device;
4141                 bio->bi_end_io = btrfs_end_super_write;
4142                 __bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE,
4143                                offset_in_page(bytenr));
4144
4145                 /*
4146                  * We FUA only the first super block.  The others we allow to
4147                  * go down lazy and there's a short window where the on-disk
4148                  * copies might still contain the older version.
4149                  */
4150                 if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
4151                         bio->bi_opf |= REQ_FUA;
4152
4153                 btrfsic_check_bio(bio);
4154                 submit_bio(bio);
4155
4156                 if (btrfs_advance_sb_log(device, i))
4157                         errors++;
4158         }
4159         return errors < i ? 0 : -1;
4160 }
4161
4162 /*
4163  * Wait for write completion of superblocks done by write_dev_supers,
4164  * @max_mirrors same for write and wait phases.
4165  *
4166  * Return number of errors when page is not found or not marked up to
4167  * date.
4168  */
4169 static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
4170 {
4171         int i;
4172         int errors = 0;
4173         bool primary_failed = false;
4174         int ret;
4175         u64 bytenr;
4176
4177         if (max_mirrors == 0)
4178                 max_mirrors = BTRFS_SUPER_MIRROR_MAX;
4179
4180         for (i = 0; i < max_mirrors; i++) {
4181                 struct page *page;
4182
4183                 ret = btrfs_sb_log_location(device, i, READ, &bytenr);
4184                 if (ret == -ENOENT) {
4185                         break;
4186                 } else if (ret < 0) {
4187                         errors++;
4188                         if (i == 0)
4189                                 primary_failed = true;
4190                         continue;
4191                 }
4192                 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
4193                     device->commit_total_bytes)
4194                         break;
4195
4196                 page = find_get_page(device->bdev->bd_inode->i_mapping,
4197                                      bytenr >> PAGE_SHIFT);
4198                 if (!page) {
4199                         errors++;
4200                         if (i == 0)
4201                                 primary_failed = true;
4202                         continue;
4203                 }
4204                 /* Page is submitted locked and unlocked once the IO completes */
4205                 wait_on_page_locked(page);
4206                 if (PageError(page)) {
4207                         errors++;
4208                         if (i == 0)
4209                                 primary_failed = true;
4210                 }
4211
4212                 /* Drop our reference */
4213                 put_page(page);
4214
4215                 /* Drop the reference from the writing run */
4216                 put_page(page);
4217         }
4218
4219         /* log error, force error return */
4220         if (primary_failed) {
4221                 btrfs_err(device->fs_info, "error writing primary super block to device %llu",
4222                           device->devid);
4223                 return -1;
4224         }
4225
4226         return errors < i ? 0 : -1;
4227 }
4228
4229 /*
4230  * endio for the write_dev_flush, this will wake anyone waiting
4231  * for the barrier when it is done
4232  */
4233 static void btrfs_end_empty_barrier(struct bio *bio)
4234 {
4235         bio_uninit(bio);
4236         complete(bio->bi_private);
4237 }
4238
4239 /*
4240  * Submit a flush request to the device if it supports it. Error handling is
4241  * done in the waiting counterpart.
4242  */
4243 static void write_dev_flush(struct btrfs_device *device)
4244 {
4245         struct bio *bio = &device->flush_bio;
4246
4247 #ifndef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4248         /*
4249          * When a disk has write caching disabled, we skip submission of a bio
4250          * with flush and sync requests before writing the superblock, since
4251          * it's not needed. However when the integrity checker is enabled, this
4252          * results in reports that there are metadata blocks referred by a
4253          * superblock that were not properly flushed. So don't skip the bio
4254          * submission only when the integrity checker is enabled for the sake
4255          * of simplicity, since this is a debug tool and not meant for use in
4256          * non-debug builds.
4257          */
4258         if (!bdev_write_cache(device->bdev))
4259                 return;
4260 #endif
4261
4262         bio_init(bio, device->bdev, NULL, 0,
4263                  REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH);
4264         bio->bi_end_io = btrfs_end_empty_barrier;
4265         init_completion(&device->flush_wait);
4266         bio->bi_private = &device->flush_wait;
4267
4268         btrfsic_check_bio(bio);
4269         submit_bio(bio);
4270         set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
4271 }
4272
4273 /*
4274  * If the flush bio has been submitted by write_dev_flush, wait for it.
4275  */
4276 static blk_status_t wait_dev_flush(struct btrfs_device *device)
4277 {
4278         struct bio *bio = &device->flush_bio;
4279
4280         if (!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
4281                 return BLK_STS_OK;
4282
4283         clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
4284         wait_for_completion_io(&device->flush_wait);
4285
4286         return bio->bi_status;
4287 }
4288
4289 static int check_barrier_error(struct btrfs_fs_info *fs_info)
4290 {
4291         if (!btrfs_check_rw_degradable(fs_info, NULL))
4292                 return -EIO;
4293         return 0;
4294 }
4295
4296 /*
4297  * send an empty flush down to each device in parallel,
4298  * then wait for them
4299  */
4300 static int barrier_all_devices(struct btrfs_fs_info *info)
4301 {
4302         struct list_head *head;
4303         struct btrfs_device *dev;
4304         int errors_wait = 0;
4305         blk_status_t ret;
4306
4307         lockdep_assert_held(&info->fs_devices->device_list_mutex);
4308         /* send down all the barriers */
4309         head = &info->fs_devices->devices;
4310         list_for_each_entry(dev, head, dev_list) {
4311                 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4312                         continue;
4313                 if (!dev->bdev)
4314                         continue;
4315                 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4316                     !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4317                         continue;
4318
4319                 write_dev_flush(dev);
4320                 dev->last_flush_error = BLK_STS_OK;
4321         }
4322
4323         /* wait for all the barriers */
4324         list_for_each_entry(dev, head, dev_list) {
4325                 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4326                         continue;
4327                 if (!dev->bdev) {
4328                         errors_wait++;
4329                         continue;
4330                 }
4331                 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4332                     !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4333                         continue;
4334
4335                 ret = wait_dev_flush(dev);
4336                 if (ret) {
4337                         dev->last_flush_error = ret;
4338                         btrfs_dev_stat_inc_and_print(dev,
4339                                         BTRFS_DEV_STAT_FLUSH_ERRS);
4340                         errors_wait++;
4341                 }
4342         }
4343
4344         if (errors_wait) {
4345                 /*
4346                  * At some point we need the status of all disks
4347                  * to arrive at the volume status. So error checking
4348                  * is being pushed to a separate loop.
4349                  */
4350                 return check_barrier_error(info);
4351         }
4352         return 0;
4353 }
4354
4355 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
4356 {
4357         int raid_type;
4358         int min_tolerated = INT_MAX;
4359
4360         if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
4361             (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
4362                 min_tolerated = min_t(int, min_tolerated,
4363                                     btrfs_raid_array[BTRFS_RAID_SINGLE].
4364                                     tolerated_failures);
4365
4366         for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4367                 if (raid_type == BTRFS_RAID_SINGLE)
4368                         continue;
4369                 if (!(flags & btrfs_raid_array[raid_type].bg_flag))
4370                         continue;
4371                 min_tolerated = min_t(int, min_tolerated,
4372                                     btrfs_raid_array[raid_type].
4373                                     tolerated_failures);
4374         }
4375
4376         if (min_tolerated == INT_MAX) {
4377                 pr_warn("BTRFS: unknown raid flag: %llu", flags);
4378                 min_tolerated = 0;
4379         }
4380
4381         return min_tolerated;
4382 }
4383
4384 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
4385 {
4386         struct list_head *head;
4387         struct btrfs_device *dev;
4388         struct btrfs_super_block *sb;
4389         struct btrfs_dev_item *dev_item;
4390         int ret;
4391         int do_barriers;
4392         int max_errors;
4393         int total_errors = 0;
4394         u64 flags;
4395
4396         do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
4397
4398         /*
4399          * max_mirrors == 0 indicates we're from commit_transaction,
4400          * not from fsync where the tree roots in fs_info have not
4401          * been consistent on disk.
4402          */
4403         if (max_mirrors == 0)
4404                 backup_super_roots(fs_info);
4405
4406         sb = fs_info->super_for_commit;
4407         dev_item = &sb->dev_item;
4408
4409         mutex_lock(&fs_info->fs_devices->device_list_mutex);
4410         head = &fs_info->fs_devices->devices;
4411         max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
4412
4413         if (do_barriers) {
4414                 ret = barrier_all_devices(fs_info);
4415                 if (ret) {
4416                         mutex_unlock(
4417                                 &fs_info->fs_devices->device_list_mutex);
4418                         btrfs_handle_fs_error(fs_info, ret,
4419                                               "errors while submitting device barriers.");
4420                         return ret;
4421                 }
4422         }
4423
4424         list_for_each_entry(dev, head, dev_list) {
4425                 if (!dev->bdev) {
4426                         total_errors++;
4427                         continue;
4428                 }
4429                 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4430                     !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4431                         continue;
4432
4433                 btrfs_set_stack_device_generation(dev_item, 0);
4434                 btrfs_set_stack_device_type(dev_item, dev->type);
4435                 btrfs_set_stack_device_id(dev_item, dev->devid);
4436                 btrfs_set_stack_device_total_bytes(dev_item,
4437                                                    dev->commit_total_bytes);
4438                 btrfs_set_stack_device_bytes_used(dev_item,
4439                                                   dev->commit_bytes_used);
4440                 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
4441                 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
4442                 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
4443                 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
4444                 memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
4445                        BTRFS_FSID_SIZE);
4446
4447                 flags = btrfs_super_flags(sb);
4448                 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
4449
4450                 ret = btrfs_validate_write_super(fs_info, sb);
4451                 if (ret < 0) {
4452                         mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4453                         btrfs_handle_fs_error(fs_info, -EUCLEAN,
4454                                 "unexpected superblock corruption detected");
4455                         return -EUCLEAN;
4456                 }
4457
4458                 ret = write_dev_supers(dev, sb, max_mirrors);
4459                 if (ret)
4460                         total_errors++;
4461         }
4462         if (total_errors > max_errors) {
4463                 btrfs_err(fs_info, "%d errors while writing supers",
4464                           total_errors);
4465                 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4466
4467                 /* FUA is masked off if unsupported and can't be the reason */
4468                 btrfs_handle_fs_error(fs_info, -EIO,
4469                                       "%d errors while writing supers",
4470                                       total_errors);
4471                 return -EIO;
4472         }
4473
4474         total_errors = 0;
4475         list_for_each_entry(dev, head, dev_list) {
4476                 if (!dev->bdev)
4477                         continue;
4478                 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4479                     !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4480                         continue;
4481
4482                 ret = wait_dev_supers(dev, max_mirrors);
4483                 if (ret)
4484                         total_errors++;
4485         }
4486         mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4487         if (total_errors > max_errors) {
4488                 btrfs_handle_fs_error(fs_info, -EIO,
4489                                       "%d errors while writing supers",
4490                                       total_errors);
4491                 return -EIO;
4492         }
4493         return 0;
4494 }
4495
4496 /* Drop a fs root from the radix tree and free it. */
4497 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
4498                                   struct btrfs_root *root)
4499 {
4500         bool drop_ref = false;
4501
4502         spin_lock(&fs_info->fs_roots_lock);
4503         xa_erase(&fs_info->fs_roots, (unsigned long)root->root_key.objectid);
4504         if (test_and_clear_bit(BTRFS_ROOT_REGISTERED, &root->state))
4505                 drop_ref = true;
4506         spin_unlock(&fs_info->fs_roots_lock);
4507
4508         if (BTRFS_FS_ERROR(fs_info)) {
4509                 ASSERT(root->log_root == NULL);
4510                 if (root->reloc_root) {
4511                         btrfs_put_root(root->reloc_root);
4512                         root->reloc_root = NULL;
4513                 }
4514         }
4515
4516         if (drop_ref)
4517                 btrfs_put_root(root);
4518 }
4519
4520 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
4521 {
4522         struct btrfs_root *roots[8];
4523         unsigned long index = 0;
4524         int i;
4525         int err = 0;
4526         int grabbed;
4527
4528         while (1) {
4529                 struct btrfs_root *root;
4530
4531                 spin_lock(&fs_info->fs_roots_lock);
4532                 if (!xa_find(&fs_info->fs_roots, &index, ULONG_MAX, XA_PRESENT)) {
4533                         spin_unlock(&fs_info->fs_roots_lock);
4534                         return err;
4535                 }
4536
4537                 grabbed = 0;
4538                 xa_for_each_start(&fs_info->fs_roots, index, root, index) {
4539                         /* Avoid grabbing roots in dead_roots */
4540                         if (btrfs_root_refs(&root->root_item) > 0)
4541                                 roots[grabbed++] = btrfs_grab_root(root);
4542                         if (grabbed >= ARRAY_SIZE(roots))
4543                                 break;
4544                 }
4545                 spin_unlock(&fs_info->fs_roots_lock);
4546
4547                 for (i = 0; i < grabbed; i++) {
4548                         if (!roots[i])
4549                                 continue;
4550                         index = roots[i]->root_key.objectid;
4551                         err = btrfs_orphan_cleanup(roots[i]);
4552                         if (err)
4553                                 goto out;
4554                         btrfs_put_root(roots[i]);
4555                 }
4556                 index++;
4557         }
4558
4559 out:
4560         /* Release the roots that remain uncleaned due to error */
4561         for (; i < grabbed; i++) {
4562                 if (roots[i])
4563                         btrfs_put_root(roots[i]);
4564         }
4565         return err;
4566 }
4567
4568 int btrfs_commit_super(struct btrfs_fs_info *fs_info)
4569 {
4570         struct btrfs_root *root = fs_info->tree_root;
4571         struct btrfs_trans_handle *trans;
4572
4573         mutex_lock(&fs_info->cleaner_mutex);
4574         btrfs_run_delayed_iputs(fs_info);
4575         mutex_unlock(&fs_info->cleaner_mutex);
4576         wake_up_process(fs_info->cleaner_kthread);
4577
4578         /* wait until ongoing cleanup work done */
4579         down_write(&fs_info->cleanup_work_sem);
4580         up_write(&fs_info->cleanup_work_sem);
4581
4582         trans = btrfs_join_transaction(root);
4583         if (IS_ERR(trans))
4584                 return PTR_ERR(trans);
4585         return btrfs_commit_transaction(trans);
4586 }
4587
4588 static void warn_about_uncommitted_trans(struct btrfs_fs_info *fs_info)
4589 {
4590         struct btrfs_transaction *trans;
4591         struct btrfs_transaction *tmp;
4592         bool found = false;
4593
4594         if (list_empty(&fs_info->trans_list))
4595                 return;
4596
4597         /*
4598          * This function is only called at the very end of close_ctree(),
4599          * thus no other running transaction, no need to take trans_lock.
4600          */
4601         ASSERT(test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags));
4602         list_for_each_entry_safe(trans, tmp, &fs_info->trans_list, list) {
4603                 struct extent_state *cached = NULL;
4604                 u64 dirty_bytes = 0;
4605                 u64 cur = 0;
4606                 u64 found_start;
4607                 u64 found_end;
4608
4609                 found = true;
4610                 while (!find_first_extent_bit(&trans->dirty_pages, cur,
4611                         &found_start, &found_end, EXTENT_DIRTY, &cached)) {
4612                         dirty_bytes += found_end + 1 - found_start;
4613                         cur = found_end + 1;
4614                 }
4615                 btrfs_warn(fs_info,
4616         "transaction %llu (with %llu dirty metadata bytes) is not committed",
4617                            trans->transid, dirty_bytes);
4618                 btrfs_cleanup_one_transaction(trans, fs_info);
4619
4620                 if (trans == fs_info->running_transaction)
4621                         fs_info->running_transaction = NULL;
4622                 list_del_init(&trans->list);
4623
4624                 btrfs_put_transaction(trans);
4625                 trace_btrfs_transaction_commit(fs_info);
4626         }
4627         ASSERT(!found);
4628 }
4629
4630 void __cold close_ctree(struct btrfs_fs_info *fs_info)
4631 {
4632         int ret;
4633
4634         set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
4635         /*
4636          * We don't want the cleaner to start new transactions, add more delayed
4637          * iputs, etc. while we're closing. We can't use kthread_stop() yet
4638          * because that frees the task_struct, and the transaction kthread might
4639          * still try to wake up the cleaner.
4640          */
4641         kthread_park(fs_info->cleaner_kthread);
4642
4643         /*
4644          * If we had UNFINISHED_DROPS we could still be processing them, so
4645          * clear that bit and wake up relocation so it can stop.
4646          */
4647         btrfs_wake_unfinished_drop(fs_info);
4648
4649         /* wait for the qgroup rescan worker to stop */
4650         btrfs_qgroup_wait_for_completion(fs_info, false);
4651
4652         /* wait for the uuid_scan task to finish */
4653         down(&fs_info->uuid_tree_rescan_sem);
4654         /* avoid complains from lockdep et al., set sem back to initial state */
4655         up(&fs_info->uuid_tree_rescan_sem);
4656
4657         /* pause restriper - we want to resume on mount */
4658         btrfs_pause_balance(fs_info);
4659
4660         btrfs_dev_replace_suspend_for_unmount(fs_info);
4661
4662         btrfs_scrub_cancel(fs_info);
4663
4664         /* wait for any defraggers to finish */
4665         wait_event(fs_info->transaction_wait,
4666                    (atomic_read(&fs_info->defrag_running) == 0));
4667
4668         /* clear out the rbtree of defraggable inodes */
4669         btrfs_cleanup_defrag_inodes(fs_info);
4670
4671         cancel_work_sync(&fs_info->async_reclaim_work);
4672         cancel_work_sync(&fs_info->async_data_reclaim_work);
4673         cancel_work_sync(&fs_info->preempt_reclaim_work);
4674
4675         cancel_work_sync(&fs_info->reclaim_bgs_work);
4676
4677         /* Cancel or finish ongoing discard work */
4678         btrfs_discard_cleanup(fs_info);
4679
4680         if (!sb_rdonly(fs_info->sb)) {
4681                 /*
4682                  * The cleaner kthread is stopped, so do one final pass over
4683                  * unused block groups.
4684                  */
4685                 btrfs_delete_unused_bgs(fs_info);
4686
4687                 /*
4688                  * There might be existing delayed inode workers still running
4689                  * and holding an empty delayed inode item. We must wait for
4690                  * them to complete first because they can create a transaction.
4691                  * This happens when someone calls btrfs_balance_delayed_items()
4692                  * and then a transaction commit runs the same delayed nodes
4693                  * before any delayed worker has done something with the nodes.
4694                  * We must wait for any worker here and not at transaction
4695                  * commit time since that could cause a deadlock.
4696                  * This is a very rare case.
4697                  */
4698                 btrfs_flush_workqueue(fs_info->delayed_workers);
4699
4700                 ret = btrfs_commit_super(fs_info);
4701                 if (ret)
4702                         btrfs_err(fs_info, "commit super ret %d", ret);
4703         }
4704
4705         if (BTRFS_FS_ERROR(fs_info))
4706                 btrfs_error_commit_super(fs_info);
4707
4708         kthread_stop(fs_info->transaction_kthread);
4709         kthread_stop(fs_info->cleaner_kthread);
4710
4711         ASSERT(list_empty(&fs_info->delayed_iputs));
4712         set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4713
4714         if (btrfs_check_quota_leak(fs_info)) {
4715                 WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4716                 btrfs_err(fs_info, "qgroup reserved space leaked");
4717         }
4718
4719         btrfs_free_qgroup_config(fs_info);
4720         ASSERT(list_empty(&fs_info->delalloc_roots));
4721
4722         if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4723                 btrfs_info(fs_info, "at unmount delalloc count %lld",
4724                        percpu_counter_sum(&fs_info->delalloc_bytes));
4725         }
4726
4727         if (percpu_counter_sum(&fs_info->ordered_bytes))
4728                 btrfs_info(fs_info, "at unmount dio bytes count %lld",
4729                            percpu_counter_sum(&fs_info->ordered_bytes));
4730
4731         btrfs_sysfs_remove_mounted(fs_info);
4732         btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4733
4734         btrfs_put_block_group_cache(fs_info);
4735
4736         /*
4737          * we must make sure there is not any read request to
4738          * submit after we stopping all workers.
4739          */
4740         invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4741         btrfs_stop_all_workers(fs_info);
4742
4743         /* We shouldn't have any transaction open at this point */
4744         warn_about_uncommitted_trans(fs_info);
4745
4746         clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
4747         free_root_pointers(fs_info, true);
4748         btrfs_free_fs_roots(fs_info);
4749
4750         /*
4751          * We must free the block groups after dropping the fs_roots as we could
4752          * have had an IO error and have left over tree log blocks that aren't
4753          * cleaned up until the fs roots are freed.  This makes the block group
4754          * accounting appear to be wrong because there's pending reserved bytes,
4755          * so make sure we do the block group cleanup afterwards.
4756          */
4757         btrfs_free_block_groups(fs_info);
4758
4759         iput(fs_info->btree_inode);
4760
4761 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4762         if (btrfs_test_opt(fs_info, CHECK_INTEGRITY))
4763                 btrfsic_unmount(fs_info->fs_devices);
4764 #endif
4765
4766         btrfs_mapping_tree_free(&fs_info->mapping_tree);
4767         btrfs_close_devices(fs_info->fs_devices);
4768 }
4769
4770 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
4771                           int atomic)
4772 {
4773         int ret;
4774         struct inode *btree_inode = buf->pages[0]->mapping->host;
4775
4776         ret = extent_buffer_uptodate(buf);
4777         if (!ret)
4778                 return ret;
4779
4780         ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
4781                                     parent_transid, atomic);
4782         if (ret == -EAGAIN)
4783                 return ret;
4784         return !ret;
4785 }
4786
4787 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
4788 {
4789         struct btrfs_fs_info *fs_info = buf->fs_info;
4790         u64 transid = btrfs_header_generation(buf);
4791         int was_dirty;
4792
4793 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4794         /*
4795          * This is a fast path so only do this check if we have sanity tests
4796          * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4797          * outside of the sanity tests.
4798          */
4799         if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4800                 return;
4801 #endif
4802         btrfs_assert_tree_write_locked(buf);
4803         if (transid != fs_info->generation)
4804                 WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, found %llu running %llu\n",
4805                         buf->start, transid, fs_info->generation);
4806         was_dirty = set_extent_buffer_dirty(buf);
4807         if (!was_dirty)
4808                 percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
4809                                          buf->len,
4810                                          fs_info->dirty_metadata_batch);
4811 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4812         /*
4813          * Since btrfs_mark_buffer_dirty() can be called with item pointer set
4814          * but item data not updated.
4815          * So here we should only check item pointers, not item data.
4816          */
4817         if (btrfs_header_level(buf) == 0 &&
4818             btrfs_check_leaf_relaxed(buf)) {
4819                 btrfs_print_leaf(buf);
4820                 ASSERT(0);
4821         }
4822 #endif
4823 }
4824
4825 static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4826                                         int flush_delayed)
4827 {
4828         /*
4829          * looks as though older kernels can get into trouble with
4830          * this code, they end up stuck in balance_dirty_pages forever
4831          */
4832         int ret;
4833
4834         if (current->flags & PF_MEMALLOC)
4835                 return;
4836
4837         if (flush_delayed)
4838                 btrfs_balance_delayed_items(fs_info);
4839
4840         ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4841                                      BTRFS_DIRTY_METADATA_THRESH,
4842                                      fs_info->dirty_metadata_batch);
4843         if (ret > 0) {
4844                 balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
4845         }
4846 }
4847
4848 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4849 {
4850         __btrfs_btree_balance_dirty(fs_info, 1);
4851 }
4852
4853 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4854 {
4855         __btrfs_btree_balance_dirty(fs_info, 0);
4856 }
4857
4858 static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4859 {
4860         /* cleanup FS via transaction */
4861         btrfs_cleanup_transaction(fs_info);
4862
4863         mutex_lock(&fs_info->cleaner_mutex);
4864         btrfs_run_delayed_iputs(fs_info);
4865         mutex_unlock(&fs_info->cleaner_mutex);
4866
4867         down_write(&fs_info->cleanup_work_sem);
4868         up_write(&fs_info->cleanup_work_sem);
4869 }
4870
4871 static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info)
4872 {
4873         unsigned long index = 0;
4874         int grabbed = 0;
4875         struct btrfs_root *roots[8];
4876
4877         spin_lock(&fs_info->fs_roots_lock);
4878         while ((grabbed = xa_extract(&fs_info->fs_roots, (void **)roots, index,
4879                                      ULONG_MAX, 8, XA_PRESENT))) {
4880                 for (int i = 0; i < grabbed; i++)
4881                         roots[i] = btrfs_grab_root(roots[i]);
4882                 spin_unlock(&fs_info->fs_roots_lock);
4883
4884                 for (int i = 0; i < grabbed; i++) {
4885                         if (!roots[i])
4886                                 continue;
4887                         index = roots[i]->root_key.objectid;
4888                         btrfs_free_log(NULL, roots[i]);
4889                         btrfs_put_root(roots[i]);
4890                 }
4891                 index++;
4892                 spin_lock(&fs_info->fs_roots_lock);
4893         }
4894         spin_unlock(&fs_info->fs_roots_lock);
4895         btrfs_free_log_root_tree(NULL, fs_info);
4896 }
4897
4898 static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4899 {
4900         struct btrfs_ordered_extent *ordered;
4901
4902         spin_lock(&root->ordered_extent_lock);
4903         /*
4904          * This will just short circuit the ordered completion stuff which will
4905          * make sure the ordered extent gets properly cleaned up.
4906          */
4907         list_for_each_entry(ordered, &root->ordered_extents,
4908                             root_extent_list)
4909                 set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4910         spin_unlock(&root->ordered_extent_lock);
4911 }
4912
4913 static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4914 {
4915         struct btrfs_root *root;
4916         struct list_head splice;
4917
4918         INIT_LIST_HEAD(&splice);
4919
4920         spin_lock(&fs_info->ordered_root_lock);
4921         list_splice_init(&fs_info->ordered_roots, &splice);
4922         while (!list_empty(&splice)) {
4923                 root = list_first_entry(&splice, struct btrfs_root,
4924                                         ordered_root);
4925                 list_move_tail(&root->ordered_root,
4926                                &fs_info->ordered_roots);
4927
4928                 spin_unlock(&fs_info->ordered_root_lock);
4929                 btrfs_destroy_ordered_extents(root);
4930
4931                 cond_resched();
4932                 spin_lock(&fs_info->ordered_root_lock);
4933         }
4934         spin_unlock(&fs_info->ordered_root_lock);
4935
4936         /*
4937          * We need this here because if we've been flipped read-only we won't
4938          * get sync() from the umount, so we need to make sure any ordered
4939          * extents that haven't had their dirty pages IO start writeout yet
4940          * actually get run and error out properly.
4941          */
4942         btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
4943 }
4944
4945 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
4946                                       struct btrfs_fs_info *fs_info)
4947 {
4948         struct rb_node *node;
4949         struct btrfs_delayed_ref_root *delayed_refs;
4950         struct btrfs_delayed_ref_node *ref;
4951         int ret = 0;
4952
4953         delayed_refs = &trans->delayed_refs;
4954
4955         spin_lock(&delayed_refs->lock);
4956         if (atomic_read(&delayed_refs->num_entries) == 0) {
4957                 spin_unlock(&delayed_refs->lock);
4958                 btrfs_debug(fs_info, "delayed_refs has NO entry");
4959                 return ret;
4960         }
4961
4962         while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
4963                 struct btrfs_delayed_ref_head *head;
4964                 struct rb_node *n;
4965                 bool pin_bytes = false;
4966
4967                 head = rb_entry(node, struct btrfs_delayed_ref_head,
4968                                 href_node);
4969                 if (btrfs_delayed_ref_lock(delayed_refs, head))
4970                         continue;
4971
4972                 spin_lock(&head->lock);
4973                 while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
4974                         ref = rb_entry(n, struct btrfs_delayed_ref_node,
4975                                        ref_node);
4976                         ref->in_tree = 0;
4977                         rb_erase_cached(&ref->ref_node, &head->ref_tree);
4978                         RB_CLEAR_NODE(&ref->ref_node);
4979                         if (!list_empty(&ref->add_list))
4980                                 list_del(&ref->add_list);
4981                         atomic_dec(&delayed_refs->num_entries);
4982                         btrfs_put_delayed_ref(ref);
4983                 }
4984                 if (head->must_insert_reserved)
4985                         pin_bytes = true;
4986                 btrfs_free_delayed_extent_op(head->extent_op);
4987                 btrfs_delete_ref_head(delayed_refs, head);
4988                 spin_unlock(&head->lock);
4989                 spin_unlock(&delayed_refs->lock);
4990                 mutex_unlock(&head->mutex);
4991
4992                 if (pin_bytes) {
4993                         struct btrfs_block_group *cache;
4994
4995                         cache = btrfs_lookup_block_group(fs_info, head->bytenr);
4996                         BUG_ON(!cache);
4997
4998                         spin_lock(&cache->space_info->lock);
4999                         spin_lock(&cache->lock);
5000                         cache->pinned += head->num_bytes;
5001                         btrfs_space_info_update_bytes_pinned(fs_info,
5002                                 cache->space_info, head->num_bytes);
5003                         cache->reserved -= head->num_bytes;
5004                         cache->space_info->bytes_reserved -= head->num_bytes;
5005                         spin_unlock(&cache->lock);
5006                         spin_unlock(&cache->space_info->lock);
5007
5008                         btrfs_put_block_group(cache);
5009
5010                         btrfs_error_unpin_extent_range(fs_info, head->bytenr,
5011                                 head->bytenr + head->num_bytes - 1);
5012                 }
5013                 btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
5014                 btrfs_put_delayed_ref_head(head);
5015                 cond_resched();
5016                 spin_lock(&delayed_refs->lock);
5017         }
5018         btrfs_qgroup_destroy_extent_records(trans);
5019
5020         spin_unlock(&delayed_refs->lock);
5021
5022         return ret;
5023 }
5024
5025 static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
5026 {
5027         struct btrfs_inode *btrfs_inode;
5028         struct list_head splice;
5029
5030         INIT_LIST_HEAD(&splice);
5031
5032         spin_lock(&root->delalloc_lock);
5033         list_splice_init(&root->delalloc_inodes, &splice);
5034
5035         while (!list_empty(&splice)) {
5036                 struct inode *inode = NULL;
5037                 btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
5038                                                delalloc_inodes);
5039                 __btrfs_del_delalloc_inode(root, btrfs_inode);
5040                 spin_unlock(&root->delalloc_lock);
5041
5042                 /*
5043                  * Make sure we get a live inode and that it'll not disappear
5044                  * meanwhile.
5045                  */
5046                 inode = igrab(&btrfs_inode->vfs_inode);
5047                 if (inode) {
5048                         invalidate_inode_pages2(inode->i_mapping);
5049                         iput(inode);
5050                 }
5051                 spin_lock(&root->delalloc_lock);
5052         }
5053         spin_unlock(&root->delalloc_lock);
5054 }
5055
5056 static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
5057 {
5058         struct btrfs_root *root;
5059         struct list_head splice;
5060
5061         INIT_LIST_HEAD(&splice);
5062
5063         spin_lock(&fs_info->delalloc_root_lock);
5064         list_splice_init(&fs_info->delalloc_roots, &splice);
5065         while (!list_empty(&splice)) {
5066                 root = list_first_entry(&splice, struct btrfs_root,
5067                                          delalloc_root);
5068                 root = btrfs_grab_root(root);
5069                 BUG_ON(!root);
5070                 spin_unlock(&fs_info->delalloc_root_lock);
5071
5072                 btrfs_destroy_delalloc_inodes(root);
5073                 btrfs_put_root(root);
5074
5075                 spin_lock(&fs_info->delalloc_root_lock);
5076         }
5077         spin_unlock(&fs_info->delalloc_root_lock);
5078 }
5079
5080 static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
5081                                         struct extent_io_tree *dirty_pages,
5082                                         int mark)
5083 {
5084         int ret;
5085         struct extent_buffer *eb;
5086         u64 start = 0;
5087         u64 end;
5088
5089         while (1) {
5090                 ret = find_first_extent_bit(dirty_pages, start, &start, &end,
5091                                             mark, NULL);
5092                 if (ret)
5093                         break;
5094
5095                 clear_extent_bits(dirty_pages, start, end, mark);
5096                 while (start <= end) {
5097                         eb = find_extent_buffer(fs_info, start);
5098                         start += fs_info->nodesize;
5099                         if (!eb)
5100                                 continue;
5101                         wait_on_extent_buffer_writeback(eb);
5102
5103                         if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
5104                                                &eb->bflags))
5105                                 clear_extent_buffer_dirty(eb);
5106                         free_extent_buffer_stale(eb);
5107                 }
5108         }
5109
5110         return ret;
5111 }
5112
5113 static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
5114                                        struct extent_io_tree *unpin)
5115 {
5116         u64 start;
5117         u64 end;
5118         int ret;
5119
5120         while (1) {
5121                 struct extent_state *cached_state = NULL;
5122
5123                 /*
5124                  * The btrfs_finish_extent_commit() may get the same range as
5125                  * ours between find_first_extent_bit and clear_extent_dirty.
5126                  * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
5127                  * the same extent range.
5128                  */
5129                 mutex_lock(&fs_info->unused_bg_unpin_mutex);
5130                 ret = find_first_extent_bit(unpin, 0, &start, &end,
5131                                             EXTENT_DIRTY, &cached_state);
5132                 if (ret) {
5133                         mutex_unlock(&fs_info->unused_bg_unpin_mutex);
5134                         break;
5135                 }
5136
5137                 clear_extent_dirty(unpin, start, end, &cached_state);
5138                 free_extent_state(cached_state);
5139                 btrfs_error_unpin_extent_range(fs_info, start, end);
5140                 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
5141                 cond_resched();
5142         }
5143
5144         return 0;
5145 }
5146
5147 static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache)
5148 {
5149         struct inode *inode;
5150
5151         inode = cache->io_ctl.inode;
5152         if (inode) {
5153                 invalidate_inode_pages2(inode->i_mapping);
5154                 BTRFS_I(inode)->generation = 0;
5155                 cache->io_ctl.inode = NULL;
5156                 iput(inode);
5157         }
5158         ASSERT(cache->io_ctl.pages == NULL);
5159         btrfs_put_block_group(cache);
5160 }
5161
5162 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
5163                              struct btrfs_fs_info *fs_info)
5164 {
5165         struct btrfs_block_group *cache;
5166
5167         spin_lock(&cur_trans->dirty_bgs_lock);
5168         while (!list_empty(&cur_trans->dirty_bgs)) {
5169                 cache = list_first_entry(&cur_trans->dirty_bgs,
5170                                          struct btrfs_block_group,
5171                                          dirty_list);
5172
5173                 if (!list_empty(&cache->io_list)) {
5174                         spin_unlock(&cur_trans->dirty_bgs_lock);
5175                         list_del_init(&cache->io_list);
5176                         btrfs_cleanup_bg_io(cache);
5177                         spin_lock(&cur_trans->dirty_bgs_lock);
5178                 }
5179
5180                 list_del_init(&cache->dirty_list);
5181                 spin_lock(&cache->lock);
5182                 cache->disk_cache_state = BTRFS_DC_ERROR;
5183                 spin_unlock(&cache->lock);
5184
5185                 spin_unlock(&cur_trans->dirty_bgs_lock);
5186                 btrfs_put_block_group(cache);
5187                 btrfs_delayed_refs_rsv_release(fs_info, 1);
5188                 spin_lock(&cur_trans->dirty_bgs_lock);
5189         }
5190         spin_unlock(&cur_trans->dirty_bgs_lock);
5191
5192         /*
5193          * Refer to the definition of io_bgs member for details why it's safe
5194          * to use it without any locking
5195          */
5196         while (!list_empty(&cur_trans->io_bgs)) {
5197                 cache = list_first_entry(&cur_trans->io_bgs,
5198                                          struct btrfs_block_group,
5199                                          io_list);
5200
5201                 list_del_init(&cache->io_list);
5202                 spin_lock(&cache->lock);
5203                 cache->disk_cache_state = BTRFS_DC_ERROR;
5204                 spin_unlock(&cache->lock);
5205                 btrfs_cleanup_bg_io(cache);
5206         }
5207 }
5208
5209 void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
5210                                    struct btrfs_fs_info *fs_info)
5211 {
5212         struct btrfs_device *dev, *tmp;
5213
5214         btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
5215         ASSERT(list_empty(&cur_trans->dirty_bgs));
5216         ASSERT(list_empty(&cur_trans->io_bgs));
5217
5218         list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
5219                                  post_commit_list) {
5220                 list_del_init(&dev->post_commit_list);
5221         }
5222
5223         btrfs_destroy_delayed_refs(cur_trans, fs_info);
5224
5225         cur_trans->state = TRANS_STATE_COMMIT_START;
5226         wake_up(&fs_info->transaction_blocked_wait);
5227
5228         cur_trans->state = TRANS_STATE_UNBLOCKED;
5229         wake_up(&fs_info->transaction_wait);
5230
5231         btrfs_destroy_delayed_inodes(fs_info);
5232
5233         btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
5234                                      EXTENT_DIRTY);
5235         btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
5236
5237         btrfs_free_redirty_list(cur_trans);
5238
5239         cur_trans->state =TRANS_STATE_COMPLETED;
5240         wake_up(&cur_trans->commit_wait);
5241 }
5242
5243 static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
5244 {
5245         struct btrfs_transaction *t;
5246
5247         mutex_lock(&fs_info->transaction_kthread_mutex);
5248
5249         spin_lock(&fs_info->trans_lock);
5250         while (!list_empty(&fs_info->trans_list)) {
5251                 t = list_first_entry(&fs_info->trans_list,
5252                                      struct btrfs_transaction, list);
5253                 if (t->state >= TRANS_STATE_COMMIT_START) {
5254                         refcount_inc(&t->use_count);
5255                         spin_unlock(&fs_info->trans_lock);
5256                         btrfs_wait_for_commit(fs_info, t->transid);
5257                         btrfs_put_transaction(t);
5258                         spin_lock(&fs_info->trans_lock);
5259                         continue;
5260                 }
5261                 if (t == fs_info->running_transaction) {
5262                         t->state = TRANS_STATE_COMMIT_DOING;
5263                         spin_unlock(&fs_info->trans_lock);
5264                         /*
5265                          * We wait for 0 num_writers since we don't hold a trans
5266                          * handle open currently for this transaction.
5267                          */
5268                         wait_event(t->writer_wait,
5269                                    atomic_read(&t->num_writers) == 0);
5270                 } else {
5271                         spin_unlock(&fs_info->trans_lock);
5272                 }
5273                 btrfs_cleanup_one_transaction(t, fs_info);
5274
5275                 spin_lock(&fs_info->trans_lock);
5276                 if (t == fs_info->running_transaction)
5277                         fs_info->running_transaction = NULL;
5278                 list_del_init(&t->list);
5279                 spin_unlock(&fs_info->trans_lock);
5280
5281                 btrfs_put_transaction(t);
5282                 trace_btrfs_transaction_commit(fs_info);
5283                 spin_lock(&fs_info->trans_lock);
5284         }
5285         spin_unlock(&fs_info->trans_lock);
5286         btrfs_destroy_all_ordered_extents(fs_info);
5287         btrfs_destroy_delayed_inodes(fs_info);
5288         btrfs_assert_delayed_root_empty(fs_info);
5289         btrfs_destroy_all_delalloc_inodes(fs_info);
5290         btrfs_drop_all_logs(fs_info);
5291         mutex_unlock(&fs_info->transaction_kthread_mutex);
5292
5293         return 0;
5294 }
5295
5296 int btrfs_init_root_free_objectid(struct btrfs_root *root)
5297 {
5298         struct btrfs_path *path;
5299         int ret;
5300         struct extent_buffer *l;
5301         struct btrfs_key search_key;
5302         struct btrfs_key found_key;
5303         int slot;
5304
5305         path = btrfs_alloc_path();
5306         if (!path)
5307                 return -ENOMEM;
5308
5309         search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
5310         search_key.type = -1;
5311         search_key.offset = (u64)-1;
5312         ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
5313         if (ret < 0)
5314                 goto error;
5315         BUG_ON(ret == 0); /* Corruption */
5316         if (path->slots[0] > 0) {
5317                 slot = path->slots[0] - 1;
5318                 l = path->nodes[0];
5319                 btrfs_item_key_to_cpu(l, &found_key, slot);
5320                 root->free_objectid = max_t(u64, found_key.objectid + 1,
5321                                             BTRFS_FIRST_FREE_OBJECTID);
5322         } else {
5323                 root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
5324         }
5325         ret = 0;
5326 error:
5327         btrfs_free_path(path);
5328         return ret;
5329 }
5330
5331 int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
5332 {
5333         int ret;
5334         mutex_lock(&root->objectid_mutex);
5335
5336         if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
5337                 btrfs_warn(root->fs_info,
5338                            "the objectid of root %llu reaches its highest value",
5339                            root->root_key.objectid);
5340                 ret = -ENOSPC;
5341                 goto out;
5342         }
5343
5344         *objectid = root->free_objectid++;
5345         ret = 0;
5346 out:
5347         mutex_unlock(&root->objectid_mutex);
5348         return ret;
5349 }