btrfs: Always try all copies when reading extent buffers
[sfrench/cifs-2.6.git] / 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/radix-tree.h>
9 #include <linux/writeback.h>
10 #include <linux/buffer_head.h>
11 #include <linux/workqueue.h>
12 #include <linux/kthread.h>
13 #include <linux/slab.h>
14 #include <linux/migrate.h>
15 #include <linux/ratelimit.h>
16 #include <linux/uuid.h>
17 #include <linux/semaphore.h>
18 #include <linux/error-injection.h>
19 #include <linux/crc32c.h>
20 #include <asm/unaligned.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 "inode-map.h"
32 #include "check-integrity.h"
33 #include "rcu-string.h"
34 #include "dev-replace.h"
35 #include "raid56.h"
36 #include "sysfs.h"
37 #include "qgroup.h"
38 #include "compression.h"
39 #include "tree-checker.h"
40 #include "ref-verify.h"
41
42 #ifdef CONFIG_X86
43 #include <asm/cpufeature.h>
44 #endif
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 const struct extent_io_ops btree_extent_io_ops;
54 static void end_workqueue_fn(struct btrfs_work *work);
55 static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
56 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
57                                       struct btrfs_fs_info *fs_info);
58 static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
59 static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
60                                         struct extent_io_tree *dirty_pages,
61                                         int mark);
62 static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
63                                        struct extent_io_tree *pinned_extents);
64 static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
65 static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
66
67 /*
68  * btrfs_end_io_wq structs are used to do processing in task context when an IO
69  * is complete.  This is used during reads to verify checksums, and it is used
70  * by writes to insert metadata for new file extents after IO is complete.
71  */
72 struct btrfs_end_io_wq {
73         struct bio *bio;
74         bio_end_io_t *end_io;
75         void *private;
76         struct btrfs_fs_info *info;
77         blk_status_t status;
78         enum btrfs_wq_endio_type metadata;
79         struct btrfs_work work;
80 };
81
82 static struct kmem_cache *btrfs_end_io_wq_cache;
83
84 int __init btrfs_end_io_wq_init(void)
85 {
86         btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
87                                         sizeof(struct btrfs_end_io_wq),
88                                         0,
89                                         SLAB_MEM_SPREAD,
90                                         NULL);
91         if (!btrfs_end_io_wq_cache)
92                 return -ENOMEM;
93         return 0;
94 }
95
96 void __cold btrfs_end_io_wq_exit(void)
97 {
98         kmem_cache_destroy(btrfs_end_io_wq_cache);
99 }
100
101 /*
102  * async submit bios are used to offload expensive checksumming
103  * onto the worker threads.  They checksum file and metadata bios
104  * just before they are sent down the IO stack.
105  */
106 struct async_submit_bio {
107         void *private_data;
108         struct bio *bio;
109         extent_submit_bio_start_t *submit_bio_start;
110         int mirror_num;
111         /*
112          * bio_offset is optional, can be used if the pages in the bio
113          * can't tell us where in the file the bio should go
114          */
115         u64 bio_offset;
116         struct btrfs_work work;
117         blk_status_t status;
118 };
119
120 /*
121  * Lockdep class keys for extent_buffer->lock's in this root.  For a given
122  * eb, the lockdep key is determined by the btrfs_root it belongs to and
123  * the level the eb occupies in the tree.
124  *
125  * Different roots are used for different purposes and may nest inside each
126  * other and they require separate keysets.  As lockdep keys should be
127  * static, assign keysets according to the purpose of the root as indicated
128  * by btrfs_root->root_key.objectid.  This ensures that all special purpose
129  * roots have separate keysets.
130  *
131  * Lock-nesting across peer nodes is always done with the immediate parent
132  * node locked thus preventing deadlock.  As lockdep doesn't know this, use
133  * subclass to avoid triggering lockdep warning in such cases.
134  *
135  * The key is set by the readpage_end_io_hook after the buffer has passed
136  * csum validation but before the pages are unlocked.  It is also set by
137  * btrfs_init_new_buffer on freshly allocated blocks.
138  *
139  * We also add a check to make sure the highest level of the tree is the
140  * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
141  * needs update as well.
142  */
143 #ifdef CONFIG_DEBUG_LOCK_ALLOC
144 # if BTRFS_MAX_LEVEL != 8
145 #  error
146 # endif
147
148 static struct btrfs_lockdep_keyset {
149         u64                     id;             /* root objectid */
150         const char              *name_stem;     /* lock name stem */
151         char                    names[BTRFS_MAX_LEVEL + 1][20];
152         struct lock_class_key   keys[BTRFS_MAX_LEVEL + 1];
153 } btrfs_lockdep_keysets[] = {
154         { .id = BTRFS_ROOT_TREE_OBJECTID,       .name_stem = "root"     },
155         { .id = BTRFS_EXTENT_TREE_OBJECTID,     .name_stem = "extent"   },
156         { .id = BTRFS_CHUNK_TREE_OBJECTID,      .name_stem = "chunk"    },
157         { .id = BTRFS_DEV_TREE_OBJECTID,        .name_stem = "dev"      },
158         { .id = BTRFS_FS_TREE_OBJECTID,         .name_stem = "fs"       },
159         { .id = BTRFS_CSUM_TREE_OBJECTID,       .name_stem = "csum"     },
160         { .id = BTRFS_QUOTA_TREE_OBJECTID,      .name_stem = "quota"    },
161         { .id = BTRFS_TREE_LOG_OBJECTID,        .name_stem = "log"      },
162         { .id = BTRFS_TREE_RELOC_OBJECTID,      .name_stem = "treloc"   },
163         { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc"   },
164         { .id = BTRFS_UUID_TREE_OBJECTID,       .name_stem = "uuid"     },
165         { .id = BTRFS_FREE_SPACE_TREE_OBJECTID, .name_stem = "free-space" },
166         { .id = 0,                              .name_stem = "tree"     },
167 };
168
169 void __init btrfs_init_lockdep(void)
170 {
171         int i, j;
172
173         /* initialize lockdep class names */
174         for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
175                 struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
176
177                 for (j = 0; j < ARRAY_SIZE(ks->names); j++)
178                         snprintf(ks->names[j], sizeof(ks->names[j]),
179                                  "btrfs-%s-%02d", ks->name_stem, j);
180         }
181 }
182
183 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
184                                     int level)
185 {
186         struct btrfs_lockdep_keyset *ks;
187
188         BUG_ON(level >= ARRAY_SIZE(ks->keys));
189
190         /* find the matching keyset, id 0 is the default entry */
191         for (ks = btrfs_lockdep_keysets; ks->id; ks++)
192                 if (ks->id == objectid)
193                         break;
194
195         lockdep_set_class_and_name(&eb->lock,
196                                    &ks->keys[level], ks->names[level]);
197 }
198
199 #endif
200
201 /*
202  * extents on the btree inode are pretty simple, there's one extent
203  * that covers the entire device
204  */
205 struct extent_map *btree_get_extent(struct btrfs_inode *inode,
206                 struct page *page, size_t pg_offset, u64 start, u64 len,
207                 int create)
208 {
209         struct btrfs_fs_info *fs_info = inode->root->fs_info;
210         struct extent_map_tree *em_tree = &inode->extent_tree;
211         struct extent_map *em;
212         int ret;
213
214         read_lock(&em_tree->lock);
215         em = lookup_extent_mapping(em_tree, start, len);
216         if (em) {
217                 em->bdev = fs_info->fs_devices->latest_bdev;
218                 read_unlock(&em_tree->lock);
219                 goto out;
220         }
221         read_unlock(&em_tree->lock);
222
223         em = alloc_extent_map();
224         if (!em) {
225                 em = ERR_PTR(-ENOMEM);
226                 goto out;
227         }
228         em->start = 0;
229         em->len = (u64)-1;
230         em->block_len = (u64)-1;
231         em->block_start = 0;
232         em->bdev = fs_info->fs_devices->latest_bdev;
233
234         write_lock(&em_tree->lock);
235         ret = add_extent_mapping(em_tree, em, 0);
236         if (ret == -EEXIST) {
237                 free_extent_map(em);
238                 em = lookup_extent_mapping(em_tree, start, len);
239                 if (!em)
240                         em = ERR_PTR(-EIO);
241         } else if (ret) {
242                 free_extent_map(em);
243                 em = ERR_PTR(ret);
244         }
245         write_unlock(&em_tree->lock);
246
247 out:
248         return em;
249 }
250
251 u32 btrfs_csum_data(const char *data, u32 seed, size_t len)
252 {
253         return crc32c(seed, data, len);
254 }
255
256 void btrfs_csum_final(u32 crc, u8 *result)
257 {
258         put_unaligned_le32(~crc, result);
259 }
260
261 /*
262  * compute the csum for a btree block, and either verify it or write it
263  * into the csum field of the block.
264  */
265 static int csum_tree_block(struct btrfs_fs_info *fs_info,
266                            struct extent_buffer *buf,
267                            int verify)
268 {
269         u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
270         char result[BTRFS_CSUM_SIZE];
271         unsigned long len;
272         unsigned long cur_len;
273         unsigned long offset = BTRFS_CSUM_SIZE;
274         char *kaddr;
275         unsigned long map_start;
276         unsigned long map_len;
277         int err;
278         u32 crc = ~(u32)0;
279
280         len = buf->len - offset;
281         while (len > 0) {
282                 err = map_private_extent_buffer(buf, offset, 32,
283                                         &kaddr, &map_start, &map_len);
284                 if (err)
285                         return err;
286                 cur_len = min(len, map_len - (offset - map_start));
287                 crc = btrfs_csum_data(kaddr + offset - map_start,
288                                       crc, cur_len);
289                 len -= cur_len;
290                 offset += cur_len;
291         }
292         memset(result, 0, BTRFS_CSUM_SIZE);
293
294         btrfs_csum_final(crc, result);
295
296         if (verify) {
297                 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
298                         u32 val;
299                         u32 found = 0;
300                         memcpy(&found, result, csum_size);
301
302                         read_extent_buffer(buf, &val, 0, csum_size);
303                         btrfs_warn_rl(fs_info,
304                                 "%s checksum verify failed on %llu wanted %X found %X level %d",
305                                 fs_info->sb->s_id, buf->start,
306                                 val, found, btrfs_header_level(buf));
307                         return -EUCLEAN;
308                 }
309         } else {
310                 write_extent_buffer(buf, result, 0, csum_size);
311         }
312
313         return 0;
314 }
315
316 /*
317  * we can't consider a given block up to date unless the transid of the
318  * block matches the transid in the parent node's pointer.  This is how we
319  * detect blocks that either didn't get written at all or got written
320  * in the wrong place.
321  */
322 static int verify_parent_transid(struct extent_io_tree *io_tree,
323                                  struct extent_buffer *eb, u64 parent_transid,
324                                  int atomic)
325 {
326         struct extent_state *cached_state = NULL;
327         int ret;
328         bool need_lock = (current->journal_info == BTRFS_SEND_TRANS_STUB);
329
330         if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
331                 return 0;
332
333         if (atomic)
334                 return -EAGAIN;
335
336         if (need_lock) {
337                 btrfs_tree_read_lock(eb);
338                 btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
339         }
340
341         lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
342                          &cached_state);
343         if (extent_buffer_uptodate(eb) &&
344             btrfs_header_generation(eb) == parent_transid) {
345                 ret = 0;
346                 goto out;
347         }
348         btrfs_err_rl(eb->fs_info,
349                 "parent transid verify failed on %llu wanted %llu found %llu",
350                         eb->start,
351                         parent_transid, btrfs_header_generation(eb));
352         ret = 1;
353
354         /*
355          * Things reading via commit roots that don't have normal protection,
356          * like send, can have a really old block in cache that may point at a
357          * block that has been freed and re-allocated.  So don't clear uptodate
358          * if we find an eb that is under IO (dirty/writeback) because we could
359          * end up reading in the stale data and then writing it back out and
360          * making everybody very sad.
361          */
362         if (!extent_buffer_under_io(eb))
363                 clear_extent_buffer_uptodate(eb);
364 out:
365         unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
366                              &cached_state);
367         if (need_lock)
368                 btrfs_tree_read_unlock_blocking(eb);
369         return ret;
370 }
371
372 /*
373  * Return 0 if the superblock checksum type matches the checksum value of that
374  * algorithm. Pass the raw disk superblock data.
375  */
376 static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
377                                   char *raw_disk_sb)
378 {
379         struct btrfs_super_block *disk_sb =
380                 (struct btrfs_super_block *)raw_disk_sb;
381         u16 csum_type = btrfs_super_csum_type(disk_sb);
382         int ret = 0;
383
384         if (csum_type == BTRFS_CSUM_TYPE_CRC32) {
385                 u32 crc = ~(u32)0;
386                 char result[sizeof(crc)];
387
388                 /*
389                  * The super_block structure does not span the whole
390                  * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space
391                  * is filled with zeros and is included in the checksum.
392                  */
393                 crc = btrfs_csum_data(raw_disk_sb + BTRFS_CSUM_SIZE,
394                                 crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
395                 btrfs_csum_final(crc, result);
396
397                 if (memcmp(raw_disk_sb, result, sizeof(result)))
398                         ret = 1;
399         }
400
401         if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
402                 btrfs_err(fs_info, "unsupported checksum algorithm %u",
403                                 csum_type);
404                 ret = 1;
405         }
406
407         return ret;
408 }
409
410 static int verify_level_key(struct btrfs_fs_info *fs_info,
411                             struct extent_buffer *eb, int level,
412                             struct btrfs_key *first_key, u64 parent_transid)
413 {
414         int found_level;
415         struct btrfs_key found_key;
416         int ret;
417
418         found_level = btrfs_header_level(eb);
419         if (found_level != level) {
420 #ifdef CONFIG_BTRFS_DEBUG
421                 WARN_ON(1);
422                 btrfs_err(fs_info,
423 "tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
424                           eb->start, level, found_level);
425 #endif
426                 return -EIO;
427         }
428
429         if (!first_key)
430                 return 0;
431
432         /*
433          * For live tree block (new tree blocks in current transaction),
434          * we need proper lock context to avoid race, which is impossible here.
435          * So we only checks tree blocks which is read from disk, whose
436          * generation <= fs_info->last_trans_committed.
437          */
438         if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
439                 return 0;
440         if (found_level)
441                 btrfs_node_key_to_cpu(eb, &found_key, 0);
442         else
443                 btrfs_item_key_to_cpu(eb, &found_key, 0);
444         ret = btrfs_comp_cpu_keys(first_key, &found_key);
445
446 #ifdef CONFIG_BTRFS_DEBUG
447         if (ret) {
448                 WARN_ON(1);
449                 btrfs_err(fs_info,
450 "tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
451                           eb->start, parent_transid, first_key->objectid,
452                           first_key->type, first_key->offset,
453                           found_key.objectid, found_key.type,
454                           found_key.offset);
455         }
456 #endif
457         return ret;
458 }
459
460 /*
461  * helper to read a given tree block, doing retries as required when
462  * the checksums don't match and we have alternate mirrors to try.
463  *
464  * @parent_transid:     expected transid, skip check if 0
465  * @level:              expected level, mandatory check
466  * @first_key:          expected key of first slot, skip check if NULL
467  */
468 static int btree_read_extent_buffer_pages(struct btrfs_fs_info *fs_info,
469                                           struct extent_buffer *eb,
470                                           u64 parent_transid, int level,
471                                           struct btrfs_key *first_key)
472 {
473         struct extent_io_tree *io_tree;
474         int failed = 0;
475         int ret;
476         int num_copies = 0;
477         int mirror_num = 0;
478         int failed_mirror = 0;
479
480         io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
481         while (1) {
482                 clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
483                 ret = read_extent_buffer_pages(io_tree, eb, WAIT_COMPLETE,
484                                                mirror_num);
485                 if (!ret) {
486                         if (verify_parent_transid(io_tree, eb,
487                                                    parent_transid, 0))
488                                 ret = -EIO;
489                         else if (verify_level_key(fs_info, eb, level,
490                                                   first_key, parent_transid))
491                                 ret = -EUCLEAN;
492                         else
493                                 break;
494                 }
495
496                 num_copies = btrfs_num_copies(fs_info,
497                                               eb->start, eb->len);
498                 if (num_copies == 1)
499                         break;
500
501                 if (!failed_mirror) {
502                         failed = 1;
503                         failed_mirror = eb->read_mirror;
504                 }
505
506                 mirror_num++;
507                 if (mirror_num == failed_mirror)
508                         mirror_num++;
509
510                 if (mirror_num > num_copies)
511                         break;
512         }
513
514         if (failed && !ret && failed_mirror)
515                 repair_eb_io_failure(fs_info, eb, failed_mirror);
516
517         return ret;
518 }
519
520 /*
521  * checksum a dirty tree block before IO.  This has extra checks to make sure
522  * we only fill in the checksum field in the first page of a multi-page block
523  */
524
525 static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
526 {
527         u64 start = page_offset(page);
528         u64 found_start;
529         struct extent_buffer *eb;
530
531         eb = (struct extent_buffer *)page->private;
532         if (page != eb->pages[0])
533                 return 0;
534
535         found_start = btrfs_header_bytenr(eb);
536         /*
537          * Please do not consolidate these warnings into a single if.
538          * It is useful to know what went wrong.
539          */
540         if (WARN_ON(found_start != start))
541                 return -EUCLEAN;
542         if (WARN_ON(!PageUptodate(page)))
543                 return -EUCLEAN;
544
545         ASSERT(memcmp_extent_buffer(eb, fs_info->fsid,
546                         btrfs_header_fsid(), BTRFS_FSID_SIZE) == 0);
547
548         return csum_tree_block(fs_info, eb, 0);
549 }
550
551 static int check_tree_block_fsid(struct btrfs_fs_info *fs_info,
552                                  struct extent_buffer *eb)
553 {
554         struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
555         u8 fsid[BTRFS_FSID_SIZE];
556         int ret = 1;
557
558         read_extent_buffer(eb, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE);
559         while (fs_devices) {
560                 if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
561                         ret = 0;
562                         break;
563                 }
564                 fs_devices = fs_devices->seed;
565         }
566         return ret;
567 }
568
569 static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
570                                       u64 phy_offset, struct page *page,
571                                       u64 start, u64 end, int mirror)
572 {
573         u64 found_start;
574         int found_level;
575         struct extent_buffer *eb;
576         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
577         struct btrfs_fs_info *fs_info = root->fs_info;
578         int ret = 0;
579         int reads_done;
580
581         if (!page->private)
582                 goto out;
583
584         eb = (struct extent_buffer *)page->private;
585
586         /* the pending IO might have been the only thing that kept this buffer
587          * in memory.  Make sure we have a ref for all this other checks
588          */
589         extent_buffer_get(eb);
590
591         reads_done = atomic_dec_and_test(&eb->io_pages);
592         if (!reads_done)
593                 goto err;
594
595         eb->read_mirror = mirror;
596         if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
597                 ret = -EIO;
598                 goto err;
599         }
600
601         found_start = btrfs_header_bytenr(eb);
602         if (found_start != eb->start) {
603                 btrfs_err_rl(fs_info, "bad tree block start, want %llu have %llu",
604                              eb->start, found_start);
605                 ret = -EIO;
606                 goto err;
607         }
608         if (check_tree_block_fsid(fs_info, eb)) {
609                 btrfs_err_rl(fs_info, "bad fsid on block %llu",
610                              eb->start);
611                 ret = -EIO;
612                 goto err;
613         }
614         found_level = btrfs_header_level(eb);
615         if (found_level >= BTRFS_MAX_LEVEL) {
616                 btrfs_err(fs_info, "bad tree block level %d on %llu",
617                           (int)btrfs_header_level(eb), eb->start);
618                 ret = -EIO;
619                 goto err;
620         }
621
622         btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
623                                        eb, found_level);
624
625         ret = csum_tree_block(fs_info, eb, 1);
626         if (ret)
627                 goto err;
628
629         /*
630          * If this is a leaf block and it is corrupt, set the corrupt bit so
631          * that we don't try and read the other copies of this block, just
632          * return -EIO.
633          */
634         if (found_level == 0 && btrfs_check_leaf_full(fs_info, eb)) {
635                 set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
636                 ret = -EIO;
637         }
638
639         if (found_level > 0 && btrfs_check_node(fs_info, eb))
640                 ret = -EIO;
641
642         if (!ret)
643                 set_extent_buffer_uptodate(eb);
644 err:
645         if (reads_done &&
646             test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
647                 btree_readahead_hook(eb, ret);
648
649         if (ret) {
650                 /*
651                  * our io error hook is going to dec the io pages
652                  * again, we have to make sure it has something
653                  * to decrement
654                  */
655                 atomic_inc(&eb->io_pages);
656                 clear_extent_buffer_uptodate(eb);
657         }
658         free_extent_buffer(eb);
659 out:
660         return ret;
661 }
662
663 static int btree_io_failed_hook(struct page *page, int failed_mirror)
664 {
665         struct extent_buffer *eb;
666
667         eb = (struct extent_buffer *)page->private;
668         set_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags);
669         eb->read_mirror = failed_mirror;
670         atomic_dec(&eb->io_pages);
671         if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
672                 btree_readahead_hook(eb, -EIO);
673         return -EIO;    /* we fixed nothing */
674 }
675
676 static void end_workqueue_bio(struct bio *bio)
677 {
678         struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
679         struct btrfs_fs_info *fs_info;
680         struct btrfs_workqueue *wq;
681         btrfs_work_func_t func;
682
683         fs_info = end_io_wq->info;
684         end_io_wq->status = bio->bi_status;
685
686         if (bio_op(bio) == REQ_OP_WRITE) {
687                 if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA) {
688                         wq = fs_info->endio_meta_write_workers;
689                         func = btrfs_endio_meta_write_helper;
690                 } else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE) {
691                         wq = fs_info->endio_freespace_worker;
692                         func = btrfs_freespace_write_helper;
693                 } else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
694                         wq = fs_info->endio_raid56_workers;
695                         func = btrfs_endio_raid56_helper;
696                 } else {
697                         wq = fs_info->endio_write_workers;
698                         func = btrfs_endio_write_helper;
699                 }
700         } else {
701                 if (unlikely(end_io_wq->metadata ==
702                              BTRFS_WQ_ENDIO_DIO_REPAIR)) {
703                         wq = fs_info->endio_repair_workers;
704                         func = btrfs_endio_repair_helper;
705                 } else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
706                         wq = fs_info->endio_raid56_workers;
707                         func = btrfs_endio_raid56_helper;
708                 } else if (end_io_wq->metadata) {
709                         wq = fs_info->endio_meta_workers;
710                         func = btrfs_endio_meta_helper;
711                 } else {
712                         wq = fs_info->endio_workers;
713                         func = btrfs_endio_helper;
714                 }
715         }
716
717         btrfs_init_work(&end_io_wq->work, func, end_workqueue_fn, NULL, NULL);
718         btrfs_queue_work(wq, &end_io_wq->work);
719 }
720
721 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
722                         enum btrfs_wq_endio_type metadata)
723 {
724         struct btrfs_end_io_wq *end_io_wq;
725
726         end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
727         if (!end_io_wq)
728                 return BLK_STS_RESOURCE;
729
730         end_io_wq->private = bio->bi_private;
731         end_io_wq->end_io = bio->bi_end_io;
732         end_io_wq->info = info;
733         end_io_wq->status = 0;
734         end_io_wq->bio = bio;
735         end_io_wq->metadata = metadata;
736
737         bio->bi_private = end_io_wq;
738         bio->bi_end_io = end_workqueue_bio;
739         return 0;
740 }
741
742 static void run_one_async_start(struct btrfs_work *work)
743 {
744         struct async_submit_bio *async;
745         blk_status_t ret;
746
747         async = container_of(work, struct  async_submit_bio, work);
748         ret = async->submit_bio_start(async->private_data, async->bio,
749                                       async->bio_offset);
750         if (ret)
751                 async->status = ret;
752 }
753
754 static void run_one_async_done(struct btrfs_work *work)
755 {
756         struct async_submit_bio *async;
757
758         async = container_of(work, struct  async_submit_bio, work);
759
760         /* If an error occurred we just want to clean up the bio and move on */
761         if (async->status) {
762                 async->bio->bi_status = async->status;
763                 bio_endio(async->bio);
764                 return;
765         }
766
767         btrfs_submit_bio_done(async->private_data, async->bio, async->mirror_num);
768 }
769
770 static void run_one_async_free(struct btrfs_work *work)
771 {
772         struct async_submit_bio *async;
773
774         async = container_of(work, struct  async_submit_bio, work);
775         kfree(async);
776 }
777
778 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
779                                  int mirror_num, unsigned long bio_flags,
780                                  u64 bio_offset, void *private_data,
781                                  extent_submit_bio_start_t *submit_bio_start)
782 {
783         struct async_submit_bio *async;
784
785         async = kmalloc(sizeof(*async), GFP_NOFS);
786         if (!async)
787                 return BLK_STS_RESOURCE;
788
789         async->private_data = private_data;
790         async->bio = bio;
791         async->mirror_num = mirror_num;
792         async->submit_bio_start = submit_bio_start;
793
794         btrfs_init_work(&async->work, btrfs_worker_helper, run_one_async_start,
795                         run_one_async_done, run_one_async_free);
796
797         async->bio_offset = bio_offset;
798
799         async->status = 0;
800
801         if (op_is_sync(bio->bi_opf))
802                 btrfs_set_work_high_priority(&async->work);
803
804         btrfs_queue_work(fs_info->workers, &async->work);
805         return 0;
806 }
807
808 static blk_status_t btree_csum_one_bio(struct bio *bio)
809 {
810         struct bio_vec *bvec;
811         struct btrfs_root *root;
812         int i, ret = 0;
813
814         ASSERT(!bio_flagged(bio, BIO_CLONED));
815         bio_for_each_segment_all(bvec, bio, i) {
816                 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
817                 ret = csum_dirty_buffer(root->fs_info, bvec->bv_page);
818                 if (ret)
819                         break;
820         }
821
822         return errno_to_blk_status(ret);
823 }
824
825 static blk_status_t btree_submit_bio_start(void *private_data, struct bio *bio,
826                                              u64 bio_offset)
827 {
828         /*
829          * when we're called for a write, we're already in the async
830          * submission context.  Just jump into btrfs_map_bio
831          */
832         return btree_csum_one_bio(bio);
833 }
834
835 static int check_async_write(struct btrfs_inode *bi)
836 {
837         if (atomic_read(&bi->sync_writers))
838                 return 0;
839 #ifdef CONFIG_X86
840         if (static_cpu_has(X86_FEATURE_XMM4_2))
841                 return 0;
842 #endif
843         return 1;
844 }
845
846 static blk_status_t btree_submit_bio_hook(void *private_data, struct bio *bio,
847                                           int mirror_num, unsigned long bio_flags,
848                                           u64 bio_offset)
849 {
850         struct inode *inode = private_data;
851         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
852         int async = check_async_write(BTRFS_I(inode));
853         blk_status_t ret;
854
855         if (bio_op(bio) != REQ_OP_WRITE) {
856                 /*
857                  * called for a read, do the setup so that checksum validation
858                  * can happen in the async kernel threads
859                  */
860                 ret = btrfs_bio_wq_end_io(fs_info, bio,
861                                           BTRFS_WQ_ENDIO_METADATA);
862                 if (ret)
863                         goto out_w_error;
864                 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
865         } else if (!async) {
866                 ret = btree_csum_one_bio(bio);
867                 if (ret)
868                         goto out_w_error;
869                 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
870         } else {
871                 /*
872                  * kthread helpers are used to submit writes so that
873                  * checksumming can happen in parallel across all CPUs
874                  */
875                 ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, 0,
876                                           bio_offset, private_data,
877                                           btree_submit_bio_start);
878         }
879
880         if (ret)
881                 goto out_w_error;
882         return 0;
883
884 out_w_error:
885         bio->bi_status = ret;
886         bio_endio(bio);
887         return ret;
888 }
889
890 #ifdef CONFIG_MIGRATION
891 static int btree_migratepage(struct address_space *mapping,
892                         struct page *newpage, struct page *page,
893                         enum migrate_mode mode)
894 {
895         /*
896          * we can't safely write a btree page from here,
897          * we haven't done the locking hook
898          */
899         if (PageDirty(page))
900                 return -EAGAIN;
901         /*
902          * Buffers may be managed in a filesystem specific way.
903          * We must have no buffers or drop them.
904          */
905         if (page_has_private(page) &&
906             !try_to_release_page(page, GFP_KERNEL))
907                 return -EAGAIN;
908         return migrate_page(mapping, newpage, page, mode);
909 }
910 #endif
911
912
913 static int btree_writepages(struct address_space *mapping,
914                             struct writeback_control *wbc)
915 {
916         struct btrfs_fs_info *fs_info;
917         int ret;
918
919         if (wbc->sync_mode == WB_SYNC_NONE) {
920
921                 if (wbc->for_kupdate)
922                         return 0;
923
924                 fs_info = BTRFS_I(mapping->host)->root->fs_info;
925                 /* this is a bit racy, but that's ok */
926                 ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
927                                              BTRFS_DIRTY_METADATA_THRESH,
928                                              fs_info->dirty_metadata_batch);
929                 if (ret < 0)
930                         return 0;
931         }
932         return btree_write_cache_pages(mapping, wbc);
933 }
934
935 static int btree_readpage(struct file *file, struct page *page)
936 {
937         struct extent_io_tree *tree;
938         tree = &BTRFS_I(page->mapping->host)->io_tree;
939         return extent_read_full_page(tree, page, btree_get_extent, 0);
940 }
941
942 static int btree_releasepage(struct page *page, gfp_t gfp_flags)
943 {
944         if (PageWriteback(page) || PageDirty(page))
945                 return 0;
946
947         return try_release_extent_buffer(page);
948 }
949
950 static void btree_invalidatepage(struct page *page, unsigned int offset,
951                                  unsigned int length)
952 {
953         struct extent_io_tree *tree;
954         tree = &BTRFS_I(page->mapping->host)->io_tree;
955         extent_invalidatepage(tree, page, offset);
956         btree_releasepage(page, GFP_NOFS);
957         if (PagePrivate(page)) {
958                 btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
959                            "page private not zero on page %llu",
960                            (unsigned long long)page_offset(page));
961                 ClearPagePrivate(page);
962                 set_page_private(page, 0);
963                 put_page(page);
964         }
965 }
966
967 static int btree_set_page_dirty(struct page *page)
968 {
969 #ifdef DEBUG
970         struct extent_buffer *eb;
971
972         BUG_ON(!PagePrivate(page));
973         eb = (struct extent_buffer *)page->private;
974         BUG_ON(!eb);
975         BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
976         BUG_ON(!atomic_read(&eb->refs));
977         btrfs_assert_tree_locked(eb);
978 #endif
979         return __set_page_dirty_nobuffers(page);
980 }
981
982 static const struct address_space_operations btree_aops = {
983         .readpage       = btree_readpage,
984         .writepages     = btree_writepages,
985         .releasepage    = btree_releasepage,
986         .invalidatepage = btree_invalidatepage,
987 #ifdef CONFIG_MIGRATION
988         .migratepage    = btree_migratepage,
989 #endif
990         .set_page_dirty = btree_set_page_dirty,
991 };
992
993 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr)
994 {
995         struct extent_buffer *buf = NULL;
996         struct inode *btree_inode = fs_info->btree_inode;
997
998         buf = btrfs_find_create_tree_block(fs_info, bytenr);
999         if (IS_ERR(buf))
1000                 return;
1001         read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
1002                                  buf, WAIT_NONE, 0);
1003         free_extent_buffer(buf);
1004 }
1005
1006 int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr,
1007                          int mirror_num, struct extent_buffer **eb)
1008 {
1009         struct extent_buffer *buf = NULL;
1010         struct inode *btree_inode = fs_info->btree_inode;
1011         struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
1012         int ret;
1013
1014         buf = btrfs_find_create_tree_block(fs_info, bytenr);
1015         if (IS_ERR(buf))
1016                 return 0;
1017
1018         set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
1019
1020         ret = read_extent_buffer_pages(io_tree, buf, WAIT_PAGE_LOCK,
1021                                        mirror_num);
1022         if (ret) {
1023                 free_extent_buffer(buf);
1024                 return ret;
1025         }
1026
1027         if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
1028                 free_extent_buffer(buf);
1029                 return -EIO;
1030         } else if (extent_buffer_uptodate(buf)) {
1031                 *eb = buf;
1032         } else {
1033                 free_extent_buffer(buf);
1034         }
1035         return 0;
1036 }
1037
1038 struct extent_buffer *btrfs_find_create_tree_block(
1039                                                 struct btrfs_fs_info *fs_info,
1040                                                 u64 bytenr)
1041 {
1042         if (btrfs_is_testing(fs_info))
1043                 return alloc_test_extent_buffer(fs_info, bytenr);
1044         return alloc_extent_buffer(fs_info, bytenr);
1045 }
1046
1047
1048 int btrfs_write_tree_block(struct extent_buffer *buf)
1049 {
1050         return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
1051                                         buf->start + buf->len - 1);
1052 }
1053
1054 void btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
1055 {
1056         filemap_fdatawait_range(buf->pages[0]->mapping,
1057                                 buf->start, buf->start + buf->len - 1);
1058 }
1059
1060 /*
1061  * Read tree block at logical address @bytenr and do variant basic but critical
1062  * verification.
1063  *
1064  * @parent_transid:     expected transid of this tree block, skip check if 0
1065  * @level:              expected level, mandatory check
1066  * @first_key:          expected key in slot 0, skip check if NULL
1067  */
1068 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
1069                                       u64 parent_transid, int level,
1070                                       struct btrfs_key *first_key)
1071 {
1072         struct extent_buffer *buf = NULL;
1073         int ret;
1074
1075         buf = btrfs_find_create_tree_block(fs_info, bytenr);
1076         if (IS_ERR(buf))
1077                 return buf;
1078
1079         ret = btree_read_extent_buffer_pages(fs_info, buf, parent_transid,
1080                                              level, first_key);
1081         if (ret) {
1082                 free_extent_buffer(buf);
1083                 return ERR_PTR(ret);
1084         }
1085         return buf;
1086
1087 }
1088
1089 void clean_tree_block(struct btrfs_fs_info *fs_info,
1090                       struct extent_buffer *buf)
1091 {
1092         if (btrfs_header_generation(buf) ==
1093             fs_info->running_transaction->transid) {
1094                 btrfs_assert_tree_locked(buf);
1095
1096                 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1097                         percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
1098                                                  -buf->len,
1099                                                  fs_info->dirty_metadata_batch);
1100                         /* ugh, clear_extent_buffer_dirty needs to lock the page */
1101                         btrfs_set_lock_blocking(buf);
1102                         clear_extent_buffer_dirty(buf);
1103                 }
1104         }
1105 }
1106
1107 static struct btrfs_subvolume_writers *btrfs_alloc_subvolume_writers(void)
1108 {
1109         struct btrfs_subvolume_writers *writers;
1110         int ret;
1111
1112         writers = kmalloc(sizeof(*writers), GFP_NOFS);
1113         if (!writers)
1114                 return ERR_PTR(-ENOMEM);
1115
1116         ret = percpu_counter_init(&writers->counter, 0, GFP_NOFS);
1117         if (ret < 0) {
1118                 kfree(writers);
1119                 return ERR_PTR(ret);
1120         }
1121
1122         init_waitqueue_head(&writers->wait);
1123         return writers;
1124 }
1125
1126 static void
1127 btrfs_free_subvolume_writers(struct btrfs_subvolume_writers *writers)
1128 {
1129         percpu_counter_destroy(&writers->counter);
1130         kfree(writers);
1131 }
1132
1133 static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
1134                          u64 objectid)
1135 {
1136         bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
1137         root->node = NULL;
1138         root->commit_root = NULL;
1139         root->state = 0;
1140         root->orphan_cleanup_state = 0;
1141
1142         root->last_trans = 0;
1143         root->highest_objectid = 0;
1144         root->nr_delalloc_inodes = 0;
1145         root->nr_ordered_extents = 0;
1146         root->inode_tree = RB_ROOT;
1147         INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1148         root->block_rsv = NULL;
1149
1150         INIT_LIST_HEAD(&root->dirty_list);
1151         INIT_LIST_HEAD(&root->root_list);
1152         INIT_LIST_HEAD(&root->delalloc_inodes);
1153         INIT_LIST_HEAD(&root->delalloc_root);
1154         INIT_LIST_HEAD(&root->ordered_extents);
1155         INIT_LIST_HEAD(&root->ordered_root);
1156         INIT_LIST_HEAD(&root->logged_list[0]);
1157         INIT_LIST_HEAD(&root->logged_list[1]);
1158         spin_lock_init(&root->inode_lock);
1159         spin_lock_init(&root->delalloc_lock);
1160         spin_lock_init(&root->ordered_extent_lock);
1161         spin_lock_init(&root->accounting_lock);
1162         spin_lock_init(&root->log_extents_lock[0]);
1163         spin_lock_init(&root->log_extents_lock[1]);
1164         spin_lock_init(&root->qgroup_meta_rsv_lock);
1165         mutex_init(&root->objectid_mutex);
1166         mutex_init(&root->log_mutex);
1167         mutex_init(&root->ordered_extent_mutex);
1168         mutex_init(&root->delalloc_mutex);
1169         init_waitqueue_head(&root->log_writer_wait);
1170         init_waitqueue_head(&root->log_commit_wait[0]);
1171         init_waitqueue_head(&root->log_commit_wait[1]);
1172         INIT_LIST_HEAD(&root->log_ctxs[0]);
1173         INIT_LIST_HEAD(&root->log_ctxs[1]);
1174         atomic_set(&root->log_commit[0], 0);
1175         atomic_set(&root->log_commit[1], 0);
1176         atomic_set(&root->log_writers, 0);
1177         atomic_set(&root->log_batch, 0);
1178         refcount_set(&root->refs, 1);
1179         atomic_set(&root->will_be_snapshotted, 0);
1180         atomic_set(&root->snapshot_force_cow, 0);
1181         root->log_transid = 0;
1182         root->log_transid_committed = -1;
1183         root->last_log_commit = 0;
1184         if (!dummy)
1185                 extent_io_tree_init(&root->dirty_log_pages, NULL);
1186
1187         memset(&root->root_key, 0, sizeof(root->root_key));
1188         memset(&root->root_item, 0, sizeof(root->root_item));
1189         memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1190         if (!dummy)
1191                 root->defrag_trans_start = fs_info->generation;
1192         else
1193                 root->defrag_trans_start = 0;
1194         root->root_key.objectid = objectid;
1195         root->anon_dev = 0;
1196
1197         spin_lock_init(&root->root_item_lock);
1198 }
1199
1200 static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1201                 gfp_t flags)
1202 {
1203         struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1204         if (root)
1205                 root->fs_info = fs_info;
1206         return root;
1207 }
1208
1209 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1210 /* Should only be used by the testing infrastructure */
1211 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
1212 {
1213         struct btrfs_root *root;
1214
1215         if (!fs_info)
1216                 return ERR_PTR(-EINVAL);
1217
1218         root = btrfs_alloc_root(fs_info, GFP_KERNEL);
1219         if (!root)
1220                 return ERR_PTR(-ENOMEM);
1221
1222         /* We don't use the stripesize in selftest, set it as sectorsize */
1223         __setup_root(root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
1224         root->alloc_bytenr = 0;
1225
1226         return root;
1227 }
1228 #endif
1229
1230 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1231                                      struct btrfs_fs_info *fs_info,
1232                                      u64 objectid)
1233 {
1234         struct extent_buffer *leaf;
1235         struct btrfs_root *tree_root = fs_info->tree_root;
1236         struct btrfs_root *root;
1237         struct btrfs_key key;
1238         int ret = 0;
1239         uuid_le uuid = NULL_UUID_LE;
1240
1241         root = btrfs_alloc_root(fs_info, GFP_KERNEL);
1242         if (!root)
1243                 return ERR_PTR(-ENOMEM);
1244
1245         __setup_root(root, fs_info, objectid);
1246         root->root_key.objectid = objectid;
1247         root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1248         root->root_key.offset = 0;
1249
1250         leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
1251         if (IS_ERR(leaf)) {
1252                 ret = PTR_ERR(leaf);
1253                 leaf = NULL;
1254                 goto fail;
1255         }
1256
1257         root->node = leaf;
1258         btrfs_mark_buffer_dirty(leaf);
1259
1260         root->commit_root = btrfs_root_node(root);
1261         set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
1262
1263         root->root_item.flags = 0;
1264         root->root_item.byte_limit = 0;
1265         btrfs_set_root_bytenr(&root->root_item, leaf->start);
1266         btrfs_set_root_generation(&root->root_item, trans->transid);
1267         btrfs_set_root_level(&root->root_item, 0);
1268         btrfs_set_root_refs(&root->root_item, 1);
1269         btrfs_set_root_used(&root->root_item, leaf->len);
1270         btrfs_set_root_last_snapshot(&root->root_item, 0);
1271         btrfs_set_root_dirid(&root->root_item, 0);
1272         if (is_fstree(objectid))
1273                 uuid_le_gen(&uuid);
1274         memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
1275         root->root_item.drop_level = 0;
1276
1277         key.objectid = objectid;
1278         key.type = BTRFS_ROOT_ITEM_KEY;
1279         key.offset = 0;
1280         ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1281         if (ret)
1282                 goto fail;
1283
1284         btrfs_tree_unlock(leaf);
1285
1286         return root;
1287
1288 fail:
1289         if (leaf) {
1290                 btrfs_tree_unlock(leaf);
1291                 free_extent_buffer(root->commit_root);
1292                 free_extent_buffer(leaf);
1293         }
1294         kfree(root);
1295
1296         return ERR_PTR(ret);
1297 }
1298
1299 static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1300                                          struct btrfs_fs_info *fs_info)
1301 {
1302         struct btrfs_root *root;
1303         struct extent_buffer *leaf;
1304
1305         root = btrfs_alloc_root(fs_info, GFP_NOFS);
1306         if (!root)
1307                 return ERR_PTR(-ENOMEM);
1308
1309         __setup_root(root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1310
1311         root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1312         root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1313         root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1314
1315         /*
1316          * DON'T set REF_COWS for log trees
1317          *
1318          * log trees do not get reference counted because they go away
1319          * before a real commit is actually done.  They do store pointers
1320          * to file data extents, and those reference counts still get
1321          * updated (along with back refs to the log tree).
1322          */
1323
1324         leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1325                         NULL, 0, 0, 0);
1326         if (IS_ERR(leaf)) {
1327                 kfree(root);
1328                 return ERR_CAST(leaf);
1329         }
1330
1331         root->node = leaf;
1332
1333         btrfs_mark_buffer_dirty(root->node);
1334         btrfs_tree_unlock(root->node);
1335         return root;
1336 }
1337
1338 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1339                              struct btrfs_fs_info *fs_info)
1340 {
1341         struct btrfs_root *log_root;
1342
1343         log_root = alloc_log_tree(trans, fs_info);
1344         if (IS_ERR(log_root))
1345                 return PTR_ERR(log_root);
1346         WARN_ON(fs_info->log_root_tree);
1347         fs_info->log_root_tree = log_root;
1348         return 0;
1349 }
1350
1351 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1352                        struct btrfs_root *root)
1353 {
1354         struct btrfs_fs_info *fs_info = root->fs_info;
1355         struct btrfs_root *log_root;
1356         struct btrfs_inode_item *inode_item;
1357
1358         log_root = alloc_log_tree(trans, fs_info);
1359         if (IS_ERR(log_root))
1360                 return PTR_ERR(log_root);
1361
1362         log_root->last_trans = trans->transid;
1363         log_root->root_key.offset = root->root_key.objectid;
1364
1365         inode_item = &log_root->root_item.inode;
1366         btrfs_set_stack_inode_generation(inode_item, 1);
1367         btrfs_set_stack_inode_size(inode_item, 3);
1368         btrfs_set_stack_inode_nlink(inode_item, 1);
1369         btrfs_set_stack_inode_nbytes(inode_item,
1370                                      fs_info->nodesize);
1371         btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1372
1373         btrfs_set_root_node(&log_root->root_item, log_root->node);
1374
1375         WARN_ON(root->log_root);
1376         root->log_root = log_root;
1377         root->log_transid = 0;
1378         root->log_transid_committed = -1;
1379         root->last_log_commit = 0;
1380         return 0;
1381 }
1382
1383 static struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1384                                                struct btrfs_key *key)
1385 {
1386         struct btrfs_root *root;
1387         struct btrfs_fs_info *fs_info = tree_root->fs_info;
1388         struct btrfs_path *path;
1389         u64 generation;
1390         int ret;
1391         int level;
1392
1393         path = btrfs_alloc_path();
1394         if (!path)
1395                 return ERR_PTR(-ENOMEM);
1396
1397         root = btrfs_alloc_root(fs_info, GFP_NOFS);
1398         if (!root) {
1399                 ret = -ENOMEM;
1400                 goto alloc_fail;
1401         }
1402
1403         __setup_root(root, fs_info, key->objectid);
1404
1405         ret = btrfs_find_root(tree_root, key, path,
1406                               &root->root_item, &root->root_key);
1407         if (ret) {
1408                 if (ret > 0)
1409                         ret = -ENOENT;
1410                 goto find_fail;
1411         }
1412
1413         generation = btrfs_root_generation(&root->root_item);
1414         level = btrfs_root_level(&root->root_item);
1415         root->node = read_tree_block(fs_info,
1416                                      btrfs_root_bytenr(&root->root_item),
1417                                      generation, level, NULL);
1418         if (IS_ERR(root->node)) {
1419                 ret = PTR_ERR(root->node);
1420                 goto find_fail;
1421         } else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1422                 ret = -EIO;
1423                 free_extent_buffer(root->node);
1424                 goto find_fail;
1425         }
1426         root->commit_root = btrfs_root_node(root);
1427 out:
1428         btrfs_free_path(path);
1429         return root;
1430
1431 find_fail:
1432         kfree(root);
1433 alloc_fail:
1434         root = ERR_PTR(ret);
1435         goto out;
1436 }
1437
1438 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
1439                                       struct btrfs_key *location)
1440 {
1441         struct btrfs_root *root;
1442
1443         root = btrfs_read_tree_root(tree_root, location);
1444         if (IS_ERR(root))
1445                 return root;
1446
1447         if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
1448                 set_bit(BTRFS_ROOT_REF_COWS, &root->state);
1449                 btrfs_check_and_init_root_item(&root->root_item);
1450         }
1451
1452         return root;
1453 }
1454
1455 int btrfs_init_fs_root(struct btrfs_root *root)
1456 {
1457         int ret;
1458         struct btrfs_subvolume_writers *writers;
1459
1460         root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1461         root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1462                                         GFP_NOFS);
1463         if (!root->free_ino_pinned || !root->free_ino_ctl) {
1464                 ret = -ENOMEM;
1465                 goto fail;
1466         }
1467
1468         writers = btrfs_alloc_subvolume_writers();
1469         if (IS_ERR(writers)) {
1470                 ret = PTR_ERR(writers);
1471                 goto fail;
1472         }
1473         root->subv_writers = writers;
1474
1475         btrfs_init_free_ino_ctl(root);
1476         spin_lock_init(&root->ino_cache_lock);
1477         init_waitqueue_head(&root->ino_cache_wait);
1478
1479         ret = get_anon_bdev(&root->anon_dev);
1480         if (ret)
1481                 goto fail;
1482
1483         mutex_lock(&root->objectid_mutex);
1484         ret = btrfs_find_highest_objectid(root,
1485                                         &root->highest_objectid);
1486         if (ret) {
1487                 mutex_unlock(&root->objectid_mutex);
1488                 goto fail;
1489         }
1490
1491         ASSERT(root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
1492
1493         mutex_unlock(&root->objectid_mutex);
1494
1495         return 0;
1496 fail:
1497         /* The caller is responsible to call btrfs_free_fs_root */
1498         return ret;
1499 }
1500
1501 struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1502                                         u64 root_id)
1503 {
1504         struct btrfs_root *root;
1505
1506         spin_lock(&fs_info->fs_roots_radix_lock);
1507         root = radix_tree_lookup(&fs_info->fs_roots_radix,
1508                                  (unsigned long)root_id);
1509         spin_unlock(&fs_info->fs_roots_radix_lock);
1510         return root;
1511 }
1512
1513 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1514                          struct btrfs_root *root)
1515 {
1516         int ret;
1517
1518         ret = radix_tree_preload(GFP_NOFS);
1519         if (ret)
1520                 return ret;
1521
1522         spin_lock(&fs_info->fs_roots_radix_lock);
1523         ret = radix_tree_insert(&fs_info->fs_roots_radix,
1524                                 (unsigned long)root->root_key.objectid,
1525                                 root);
1526         if (ret == 0)
1527                 set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
1528         spin_unlock(&fs_info->fs_roots_radix_lock);
1529         radix_tree_preload_end();
1530
1531         return ret;
1532 }
1533
1534 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1535                                      struct btrfs_key *location,
1536                                      bool check_ref)
1537 {
1538         struct btrfs_root *root;
1539         struct btrfs_path *path;
1540         struct btrfs_key key;
1541         int ret;
1542
1543         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1544                 return fs_info->tree_root;
1545         if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1546                 return fs_info->extent_root;
1547         if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1548                 return fs_info->chunk_root;
1549         if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1550                 return fs_info->dev_root;
1551         if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1552                 return fs_info->csum_root;
1553         if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
1554                 return fs_info->quota_root ? fs_info->quota_root :
1555                                              ERR_PTR(-ENOENT);
1556         if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
1557                 return fs_info->uuid_root ? fs_info->uuid_root :
1558                                             ERR_PTR(-ENOENT);
1559         if (location->objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
1560                 return fs_info->free_space_root ? fs_info->free_space_root :
1561                                                   ERR_PTR(-ENOENT);
1562 again:
1563         root = btrfs_lookup_fs_root(fs_info, location->objectid);
1564         if (root) {
1565                 if (check_ref && btrfs_root_refs(&root->root_item) == 0)
1566                         return ERR_PTR(-ENOENT);
1567                 return root;
1568         }
1569
1570         root = btrfs_read_fs_root(fs_info->tree_root, location);
1571         if (IS_ERR(root))
1572                 return root;
1573
1574         if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1575                 ret = -ENOENT;
1576                 goto fail;
1577         }
1578
1579         ret = btrfs_init_fs_root(root);
1580         if (ret)
1581                 goto fail;
1582
1583         path = btrfs_alloc_path();
1584         if (!path) {
1585                 ret = -ENOMEM;
1586                 goto fail;
1587         }
1588         key.objectid = BTRFS_ORPHAN_OBJECTID;
1589         key.type = BTRFS_ORPHAN_ITEM_KEY;
1590         key.offset = location->objectid;
1591
1592         ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1593         btrfs_free_path(path);
1594         if (ret < 0)
1595                 goto fail;
1596         if (ret == 0)
1597                 set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1598
1599         ret = btrfs_insert_fs_root(fs_info, root);
1600         if (ret) {
1601                 if (ret == -EEXIST) {
1602                         btrfs_free_fs_root(root);
1603                         goto again;
1604                 }
1605                 goto fail;
1606         }
1607         return root;
1608 fail:
1609         btrfs_free_fs_root(root);
1610         return ERR_PTR(ret);
1611 }
1612
1613 static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1614 {
1615         struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1616         int ret = 0;
1617         struct btrfs_device *device;
1618         struct backing_dev_info *bdi;
1619
1620         rcu_read_lock();
1621         list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1622                 if (!device->bdev)
1623                         continue;
1624                 bdi = device->bdev->bd_bdi;
1625                 if (bdi_congested(bdi, bdi_bits)) {
1626                         ret = 1;
1627                         break;
1628                 }
1629         }
1630         rcu_read_unlock();
1631         return ret;
1632 }
1633
1634 /*
1635  * called by the kthread helper functions to finally call the bio end_io
1636  * functions.  This is where read checksum verification actually happens
1637  */
1638 static void end_workqueue_fn(struct btrfs_work *work)
1639 {
1640         struct bio *bio;
1641         struct btrfs_end_io_wq *end_io_wq;
1642
1643         end_io_wq = container_of(work, struct btrfs_end_io_wq, work);
1644         bio = end_io_wq->bio;
1645
1646         bio->bi_status = end_io_wq->status;
1647         bio->bi_private = end_io_wq->private;
1648         bio->bi_end_io = end_io_wq->end_io;
1649         kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
1650         bio_endio(bio);
1651 }
1652
1653 static int cleaner_kthread(void *arg)
1654 {
1655         struct btrfs_root *root = arg;
1656         struct btrfs_fs_info *fs_info = root->fs_info;
1657         int again;
1658
1659         while (1) {
1660                 again = 0;
1661
1662                 /* Make the cleaner go to sleep early. */
1663                 if (btrfs_need_cleaner_sleep(fs_info))
1664                         goto sleep;
1665
1666                 /*
1667                  * Do not do anything if we might cause open_ctree() to block
1668                  * before we have finished mounting the filesystem.
1669                  */
1670                 if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1671                         goto sleep;
1672
1673                 if (!mutex_trylock(&fs_info->cleaner_mutex))
1674                         goto sleep;
1675
1676                 /*
1677                  * Avoid the problem that we change the status of the fs
1678                  * during the above check and trylock.
1679                  */
1680                 if (btrfs_need_cleaner_sleep(fs_info)) {
1681                         mutex_unlock(&fs_info->cleaner_mutex);
1682                         goto sleep;
1683                 }
1684
1685                 mutex_lock(&fs_info->cleaner_delayed_iput_mutex);
1686                 btrfs_run_delayed_iputs(fs_info);
1687                 mutex_unlock(&fs_info->cleaner_delayed_iput_mutex);
1688
1689                 again = btrfs_clean_one_deleted_snapshot(root);
1690                 mutex_unlock(&fs_info->cleaner_mutex);
1691
1692                 /*
1693                  * The defragger has dealt with the R/O remount and umount,
1694                  * needn't do anything special here.
1695                  */
1696                 btrfs_run_defrag_inodes(fs_info);
1697
1698                 /*
1699                  * Acquires fs_info->delete_unused_bgs_mutex to avoid racing
1700                  * with relocation (btrfs_relocate_chunk) and relocation
1701                  * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1702                  * after acquiring fs_info->delete_unused_bgs_mutex. So we
1703                  * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1704                  * unused block groups.
1705                  */
1706                 btrfs_delete_unused_bgs(fs_info);
1707 sleep:
1708                 if (kthread_should_park())
1709                         kthread_parkme();
1710                 if (kthread_should_stop())
1711                         return 0;
1712                 if (!again) {
1713                         set_current_state(TASK_INTERRUPTIBLE);
1714                         schedule();
1715                         __set_current_state(TASK_RUNNING);
1716                 }
1717         }
1718 }
1719
1720 static int transaction_kthread(void *arg)
1721 {
1722         struct btrfs_root *root = arg;
1723         struct btrfs_fs_info *fs_info = root->fs_info;
1724         struct btrfs_trans_handle *trans;
1725         struct btrfs_transaction *cur;
1726         u64 transid;
1727         time64_t now;
1728         unsigned long delay;
1729         bool cannot_commit;
1730
1731         do {
1732                 cannot_commit = false;
1733                 delay = HZ * fs_info->commit_interval;
1734                 mutex_lock(&fs_info->transaction_kthread_mutex);
1735
1736                 spin_lock(&fs_info->trans_lock);
1737                 cur = fs_info->running_transaction;
1738                 if (!cur) {
1739                         spin_unlock(&fs_info->trans_lock);
1740                         goto sleep;
1741                 }
1742
1743                 now = ktime_get_seconds();
1744                 if (cur->state < TRANS_STATE_BLOCKED &&
1745                     !test_bit(BTRFS_FS_NEED_ASYNC_COMMIT, &fs_info->flags) &&
1746                     (now < cur->start_time ||
1747                      now - cur->start_time < fs_info->commit_interval)) {
1748                         spin_unlock(&fs_info->trans_lock);
1749                         delay = HZ * 5;
1750                         goto sleep;
1751                 }
1752                 transid = cur->transid;
1753                 spin_unlock(&fs_info->trans_lock);
1754
1755                 /* If the file system is aborted, this will always fail. */
1756                 trans = btrfs_attach_transaction(root);
1757                 if (IS_ERR(trans)) {
1758                         if (PTR_ERR(trans) != -ENOENT)
1759                                 cannot_commit = true;
1760                         goto sleep;
1761                 }
1762                 if (transid == trans->transid) {
1763                         btrfs_commit_transaction(trans);
1764                 } else {
1765                         btrfs_end_transaction(trans);
1766                 }
1767 sleep:
1768                 wake_up_process(fs_info->cleaner_kthread);
1769                 mutex_unlock(&fs_info->transaction_kthread_mutex);
1770
1771                 if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
1772                                       &fs_info->fs_state)))
1773                         btrfs_cleanup_transaction(fs_info);
1774                 if (!kthread_should_stop() &&
1775                                 (!btrfs_transaction_blocked(fs_info) ||
1776                                  cannot_commit))
1777                         schedule_timeout_interruptible(delay);
1778         } while (!kthread_should_stop());
1779         return 0;
1780 }
1781
1782 /*
1783  * this will find the highest generation in the array of
1784  * root backups.  The index of the highest array is returned,
1785  * or -1 if we can't find anything.
1786  *
1787  * We check to make sure the array is valid by comparing the
1788  * generation of the latest  root in the array with the generation
1789  * in the super block.  If they don't match we pitch it.
1790  */
1791 static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1792 {
1793         u64 cur;
1794         int newest_index = -1;
1795         struct btrfs_root_backup *root_backup;
1796         int i;
1797
1798         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1799                 root_backup = info->super_copy->super_roots + i;
1800                 cur = btrfs_backup_tree_root_gen(root_backup);
1801                 if (cur == newest_gen)
1802                         newest_index = i;
1803         }
1804
1805         /* check to see if we actually wrapped around */
1806         if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1807                 root_backup = info->super_copy->super_roots;
1808                 cur = btrfs_backup_tree_root_gen(root_backup);
1809                 if (cur == newest_gen)
1810                         newest_index = 0;
1811         }
1812         return newest_index;
1813 }
1814
1815
1816 /*
1817  * find the oldest backup so we know where to store new entries
1818  * in the backup array.  This will set the backup_root_index
1819  * field in the fs_info struct
1820  */
1821 static void find_oldest_super_backup(struct btrfs_fs_info *info,
1822                                      u64 newest_gen)
1823 {
1824         int newest_index = -1;
1825
1826         newest_index = find_newest_super_backup(info, newest_gen);
1827         /* if there was garbage in there, just move along */
1828         if (newest_index == -1) {
1829                 info->backup_root_index = 0;
1830         } else {
1831                 info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1832         }
1833 }
1834
1835 /*
1836  * copy all the root pointers into the super backup array.
1837  * this will bump the backup pointer by one when it is
1838  * done
1839  */
1840 static void backup_super_roots(struct btrfs_fs_info *info)
1841 {
1842         int next_backup;
1843         struct btrfs_root_backup *root_backup;
1844         int last_backup;
1845
1846         next_backup = info->backup_root_index;
1847         last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1848                 BTRFS_NUM_BACKUP_ROOTS;
1849
1850         /*
1851          * just overwrite the last backup if we're at the same generation
1852          * this happens only at umount
1853          */
1854         root_backup = info->super_for_commit->super_roots + last_backup;
1855         if (btrfs_backup_tree_root_gen(root_backup) ==
1856             btrfs_header_generation(info->tree_root->node))
1857                 next_backup = last_backup;
1858
1859         root_backup = info->super_for_commit->super_roots + next_backup;
1860
1861         /*
1862          * make sure all of our padding and empty slots get zero filled
1863          * regardless of which ones we use today
1864          */
1865         memset(root_backup, 0, sizeof(*root_backup));
1866
1867         info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1868
1869         btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1870         btrfs_set_backup_tree_root_gen(root_backup,
1871                                btrfs_header_generation(info->tree_root->node));
1872
1873         btrfs_set_backup_tree_root_level(root_backup,
1874                                btrfs_header_level(info->tree_root->node));
1875
1876         btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1877         btrfs_set_backup_chunk_root_gen(root_backup,
1878                                btrfs_header_generation(info->chunk_root->node));
1879         btrfs_set_backup_chunk_root_level(root_backup,
1880                                btrfs_header_level(info->chunk_root->node));
1881
1882         btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1883         btrfs_set_backup_extent_root_gen(root_backup,
1884                                btrfs_header_generation(info->extent_root->node));
1885         btrfs_set_backup_extent_root_level(root_backup,
1886                                btrfs_header_level(info->extent_root->node));
1887
1888         /*
1889          * we might commit during log recovery, which happens before we set
1890          * the fs_root.  Make sure it is valid before we fill it in.
1891          */
1892         if (info->fs_root && info->fs_root->node) {
1893                 btrfs_set_backup_fs_root(root_backup,
1894                                          info->fs_root->node->start);
1895                 btrfs_set_backup_fs_root_gen(root_backup,
1896                                btrfs_header_generation(info->fs_root->node));
1897                 btrfs_set_backup_fs_root_level(root_backup,
1898                                btrfs_header_level(info->fs_root->node));
1899         }
1900
1901         btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1902         btrfs_set_backup_dev_root_gen(root_backup,
1903                                btrfs_header_generation(info->dev_root->node));
1904         btrfs_set_backup_dev_root_level(root_backup,
1905                                        btrfs_header_level(info->dev_root->node));
1906
1907         btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1908         btrfs_set_backup_csum_root_gen(root_backup,
1909                                btrfs_header_generation(info->csum_root->node));
1910         btrfs_set_backup_csum_root_level(root_backup,
1911                                btrfs_header_level(info->csum_root->node));
1912
1913         btrfs_set_backup_total_bytes(root_backup,
1914                              btrfs_super_total_bytes(info->super_copy));
1915         btrfs_set_backup_bytes_used(root_backup,
1916                              btrfs_super_bytes_used(info->super_copy));
1917         btrfs_set_backup_num_devices(root_backup,
1918                              btrfs_super_num_devices(info->super_copy));
1919
1920         /*
1921          * if we don't copy this out to the super_copy, it won't get remembered
1922          * for the next commit
1923          */
1924         memcpy(&info->super_copy->super_roots,
1925                &info->super_for_commit->super_roots,
1926                sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1927 }
1928
1929 /*
1930  * this copies info out of the root backup array and back into
1931  * the in-memory super block.  It is meant to help iterate through
1932  * the array, so you send it the number of backups you've already
1933  * tried and the last backup index you used.
1934  *
1935  * this returns -1 when it has tried all the backups
1936  */
1937 static noinline int next_root_backup(struct btrfs_fs_info *info,
1938                                      struct btrfs_super_block *super,
1939                                      int *num_backups_tried, int *backup_index)
1940 {
1941         struct btrfs_root_backup *root_backup;
1942         int newest = *backup_index;
1943
1944         if (*num_backups_tried == 0) {
1945                 u64 gen = btrfs_super_generation(super);
1946
1947                 newest = find_newest_super_backup(info, gen);
1948                 if (newest == -1)
1949                         return -1;
1950
1951                 *backup_index = newest;
1952                 *num_backups_tried = 1;
1953         } else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
1954                 /* we've tried all the backups, all done */
1955                 return -1;
1956         } else {
1957                 /* jump to the next oldest backup */
1958                 newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
1959                         BTRFS_NUM_BACKUP_ROOTS;
1960                 *backup_index = newest;
1961                 *num_backups_tried += 1;
1962         }
1963         root_backup = super->super_roots + newest;
1964
1965         btrfs_set_super_generation(super,
1966                                    btrfs_backup_tree_root_gen(root_backup));
1967         btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1968         btrfs_set_super_root_level(super,
1969                                    btrfs_backup_tree_root_level(root_backup));
1970         btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1971
1972         /*
1973          * fixme: the total bytes and num_devices need to match or we should
1974          * need a fsck
1975          */
1976         btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1977         btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1978         return 0;
1979 }
1980
1981 /* helper to cleanup workers */
1982 static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
1983 {
1984         btrfs_destroy_workqueue(fs_info->fixup_workers);
1985         btrfs_destroy_workqueue(fs_info->delalloc_workers);
1986         btrfs_destroy_workqueue(fs_info->workers);
1987         btrfs_destroy_workqueue(fs_info->endio_workers);
1988         btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
1989         btrfs_destroy_workqueue(fs_info->endio_repair_workers);
1990         btrfs_destroy_workqueue(fs_info->rmw_workers);
1991         btrfs_destroy_workqueue(fs_info->endio_write_workers);
1992         btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
1993         btrfs_destroy_workqueue(fs_info->submit_workers);
1994         btrfs_destroy_workqueue(fs_info->delayed_workers);
1995         btrfs_destroy_workqueue(fs_info->caching_workers);
1996         btrfs_destroy_workqueue(fs_info->readahead_workers);
1997         btrfs_destroy_workqueue(fs_info->flush_workers);
1998         btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
1999         btrfs_destroy_workqueue(fs_info->extent_workers);
2000         /*
2001          * Now that all other work queues are destroyed, we can safely destroy
2002          * the queues used for metadata I/O, since tasks from those other work
2003          * queues can do metadata I/O operations.
2004          */
2005         btrfs_destroy_workqueue(fs_info->endio_meta_workers);
2006         btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
2007 }
2008
2009 static void free_root_extent_buffers(struct btrfs_root *root)
2010 {
2011         if (root) {
2012                 free_extent_buffer(root->node);
2013                 free_extent_buffer(root->commit_root);
2014                 root->node = NULL;
2015                 root->commit_root = NULL;
2016         }
2017 }
2018
2019 /* helper to cleanup tree roots */
2020 static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
2021 {
2022         free_root_extent_buffers(info->tree_root);
2023
2024         free_root_extent_buffers(info->dev_root);
2025         free_root_extent_buffers(info->extent_root);
2026         free_root_extent_buffers(info->csum_root);
2027         free_root_extent_buffers(info->quota_root);
2028         free_root_extent_buffers(info->uuid_root);
2029         if (chunk_root)
2030                 free_root_extent_buffers(info->chunk_root);
2031         free_root_extent_buffers(info->free_space_root);
2032 }
2033
2034 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2035 {
2036         int ret;
2037         struct btrfs_root *gang[8];
2038         int i;
2039
2040         while (!list_empty(&fs_info->dead_roots)) {
2041                 gang[0] = list_entry(fs_info->dead_roots.next,
2042                                      struct btrfs_root, root_list);
2043                 list_del(&gang[0]->root_list);
2044
2045                 if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state)) {
2046                         btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2047                 } else {
2048                         free_extent_buffer(gang[0]->node);
2049                         free_extent_buffer(gang[0]->commit_root);
2050                         btrfs_put_fs_root(gang[0]);
2051                 }
2052         }
2053
2054         while (1) {
2055                 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2056                                              (void **)gang, 0,
2057                                              ARRAY_SIZE(gang));
2058                 if (!ret)
2059                         break;
2060                 for (i = 0; i < ret; i++)
2061                         btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2062         }
2063
2064         if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
2065                 btrfs_free_log_root_tree(NULL, fs_info);
2066                 btrfs_destroy_pinned_extent(fs_info, fs_info->pinned_extents);
2067         }
2068 }
2069
2070 static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2071 {
2072         mutex_init(&fs_info->scrub_lock);
2073         atomic_set(&fs_info->scrubs_running, 0);
2074         atomic_set(&fs_info->scrub_pause_req, 0);
2075         atomic_set(&fs_info->scrubs_paused, 0);
2076         atomic_set(&fs_info->scrub_cancel_req, 0);
2077         init_waitqueue_head(&fs_info->scrub_pause_wait);
2078         fs_info->scrub_workers_refcnt = 0;
2079 }
2080
2081 static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2082 {
2083         spin_lock_init(&fs_info->balance_lock);
2084         mutex_init(&fs_info->balance_mutex);
2085         atomic_set(&fs_info->balance_pause_req, 0);
2086         atomic_set(&fs_info->balance_cancel_req, 0);
2087         fs_info->balance_ctl = NULL;
2088         init_waitqueue_head(&fs_info->balance_wait_q);
2089 }
2090
2091 static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
2092 {
2093         struct inode *inode = fs_info->btree_inode;
2094
2095         inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2096         set_nlink(inode, 1);
2097         /*
2098          * we set the i_size on the btree inode to the max possible int.
2099          * the real end of the address space is determined by all of
2100          * the devices in the system
2101          */
2102         inode->i_size = OFFSET_MAX;
2103         inode->i_mapping->a_ops = &btree_aops;
2104
2105         RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
2106         extent_io_tree_init(&BTRFS_I(inode)->io_tree, inode);
2107         BTRFS_I(inode)->io_tree.track_uptodate = 0;
2108         extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
2109
2110         BTRFS_I(inode)->io_tree.ops = &btree_extent_io_ops;
2111
2112         BTRFS_I(inode)->root = fs_info->tree_root;
2113         memset(&BTRFS_I(inode)->location, 0, sizeof(struct btrfs_key));
2114         set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
2115         btrfs_insert_inode_hash(inode);
2116 }
2117
2118 static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2119 {
2120         mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2121         rwlock_init(&fs_info->dev_replace.lock);
2122         atomic_set(&fs_info->dev_replace.blocking_readers, 0);
2123         init_waitqueue_head(&fs_info->dev_replace.replace_wait);
2124         init_waitqueue_head(&fs_info->dev_replace.read_lock_wq);
2125 }
2126
2127 static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2128 {
2129         spin_lock_init(&fs_info->qgroup_lock);
2130         mutex_init(&fs_info->qgroup_ioctl_lock);
2131         fs_info->qgroup_tree = RB_ROOT;
2132         fs_info->qgroup_op_tree = RB_ROOT;
2133         INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2134         fs_info->qgroup_seq = 1;
2135         fs_info->qgroup_ulist = NULL;
2136         fs_info->qgroup_rescan_running = false;
2137         mutex_init(&fs_info->qgroup_rescan_lock);
2138 }
2139
2140 static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
2141                 struct btrfs_fs_devices *fs_devices)
2142 {
2143         u32 max_active = fs_info->thread_pool_size;
2144         unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
2145
2146         fs_info->workers =
2147                 btrfs_alloc_workqueue(fs_info, "worker",
2148                                       flags | WQ_HIGHPRI, max_active, 16);
2149
2150         fs_info->delalloc_workers =
2151                 btrfs_alloc_workqueue(fs_info, "delalloc",
2152                                       flags, max_active, 2);
2153
2154         fs_info->flush_workers =
2155                 btrfs_alloc_workqueue(fs_info, "flush_delalloc",
2156                                       flags, max_active, 0);
2157
2158         fs_info->caching_workers =
2159                 btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
2160
2161         /*
2162          * a higher idle thresh on the submit workers makes it much more
2163          * likely that bios will be send down in a sane order to the
2164          * devices
2165          */
2166         fs_info->submit_workers =
2167                 btrfs_alloc_workqueue(fs_info, "submit", flags,
2168                                       min_t(u64, fs_devices->num_devices,
2169                                             max_active), 64);
2170
2171         fs_info->fixup_workers =
2172                 btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0);
2173
2174         /*
2175          * endios are largely parallel and should have a very
2176          * low idle thresh
2177          */
2178         fs_info->endio_workers =
2179                 btrfs_alloc_workqueue(fs_info, "endio", flags, max_active, 4);
2180         fs_info->endio_meta_workers =
2181                 btrfs_alloc_workqueue(fs_info, "endio-meta", flags,
2182                                       max_active, 4);
2183         fs_info->endio_meta_write_workers =
2184                 btrfs_alloc_workqueue(fs_info, "endio-meta-write", flags,
2185                                       max_active, 2);
2186         fs_info->endio_raid56_workers =
2187                 btrfs_alloc_workqueue(fs_info, "endio-raid56", flags,
2188                                       max_active, 4);
2189         fs_info->endio_repair_workers =
2190                 btrfs_alloc_workqueue(fs_info, "endio-repair", flags, 1, 0);
2191         fs_info->rmw_workers =
2192                 btrfs_alloc_workqueue(fs_info, "rmw", flags, max_active, 2);
2193         fs_info->endio_write_workers =
2194                 btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2195                                       max_active, 2);
2196         fs_info->endio_freespace_worker =
2197                 btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2198                                       max_active, 0);
2199         fs_info->delayed_workers =
2200                 btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2201                                       max_active, 0);
2202         fs_info->readahead_workers =
2203                 btrfs_alloc_workqueue(fs_info, "readahead", flags,
2204                                       max_active, 2);
2205         fs_info->qgroup_rescan_workers =
2206                 btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0);
2207         fs_info->extent_workers =
2208                 btrfs_alloc_workqueue(fs_info, "extent-refs", flags,
2209                                       min_t(u64, fs_devices->num_devices,
2210                                             max_active), 8);
2211
2212         if (!(fs_info->workers && fs_info->delalloc_workers &&
2213               fs_info->submit_workers && fs_info->flush_workers &&
2214               fs_info->endio_workers && fs_info->endio_meta_workers &&
2215               fs_info->endio_meta_write_workers &&
2216               fs_info->endio_repair_workers &&
2217               fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
2218               fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2219               fs_info->caching_workers && fs_info->readahead_workers &&
2220               fs_info->fixup_workers && fs_info->delayed_workers &&
2221               fs_info->extent_workers &&
2222               fs_info->qgroup_rescan_workers)) {
2223                 return -ENOMEM;
2224         }
2225
2226         return 0;
2227 }
2228
2229 static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2230                             struct btrfs_fs_devices *fs_devices)
2231 {
2232         int ret;
2233         struct btrfs_root *log_tree_root;
2234         struct btrfs_super_block *disk_super = fs_info->super_copy;
2235         u64 bytenr = btrfs_super_log_root(disk_super);
2236         int level = btrfs_super_log_root_level(disk_super);
2237
2238         if (fs_devices->rw_devices == 0) {
2239                 btrfs_warn(fs_info, "log replay required on RO media");
2240                 return -EIO;
2241         }
2242
2243         log_tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2244         if (!log_tree_root)
2245                 return -ENOMEM;
2246
2247         __setup_root(log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2248
2249         log_tree_root->node = read_tree_block(fs_info, bytenr,
2250                                               fs_info->generation + 1,
2251                                               level, NULL);
2252         if (IS_ERR(log_tree_root->node)) {
2253                 btrfs_warn(fs_info, "failed to read log tree");
2254                 ret = PTR_ERR(log_tree_root->node);
2255                 kfree(log_tree_root);
2256                 return ret;
2257         } else if (!extent_buffer_uptodate(log_tree_root->node)) {
2258                 btrfs_err(fs_info, "failed to read log tree");
2259                 free_extent_buffer(log_tree_root->node);
2260                 kfree(log_tree_root);
2261                 return -EIO;
2262         }
2263         /* returns with log_tree_root freed on success */
2264         ret = btrfs_recover_log_trees(log_tree_root);
2265         if (ret) {
2266                 btrfs_handle_fs_error(fs_info, ret,
2267                                       "Failed to recover log tree");
2268                 free_extent_buffer(log_tree_root->node);
2269                 kfree(log_tree_root);
2270                 return ret;
2271         }
2272
2273         if (sb_rdonly(fs_info->sb)) {
2274                 ret = btrfs_commit_super(fs_info);
2275                 if (ret)
2276                         return ret;
2277         }
2278
2279         return 0;
2280 }
2281
2282 static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2283 {
2284         struct btrfs_root *tree_root = fs_info->tree_root;
2285         struct btrfs_root *root;
2286         struct btrfs_key location;
2287         int ret;
2288
2289         BUG_ON(!fs_info->tree_root);
2290
2291         location.objectid = BTRFS_EXTENT_TREE_OBJECTID;
2292         location.type = BTRFS_ROOT_ITEM_KEY;
2293         location.offset = 0;
2294
2295         root = btrfs_read_tree_root(tree_root, &location);
2296         if (IS_ERR(root)) {
2297                 ret = PTR_ERR(root);
2298                 goto out;
2299         }
2300         set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2301         fs_info->extent_root = root;
2302
2303         location.objectid = BTRFS_DEV_TREE_OBJECTID;
2304         root = btrfs_read_tree_root(tree_root, &location);
2305         if (IS_ERR(root)) {
2306                 ret = PTR_ERR(root);
2307                 goto out;
2308         }
2309         set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2310         fs_info->dev_root = root;
2311         btrfs_init_devices_late(fs_info);
2312
2313         location.objectid = BTRFS_CSUM_TREE_OBJECTID;
2314         root = btrfs_read_tree_root(tree_root, &location);
2315         if (IS_ERR(root)) {
2316                 ret = PTR_ERR(root);
2317                 goto out;
2318         }
2319         set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2320         fs_info->csum_root = root;
2321
2322         location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2323         root = btrfs_read_tree_root(tree_root, &location);
2324         if (!IS_ERR(root)) {
2325                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2326                 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
2327                 fs_info->quota_root = root;
2328         }
2329
2330         location.objectid = BTRFS_UUID_TREE_OBJECTID;
2331         root = btrfs_read_tree_root(tree_root, &location);
2332         if (IS_ERR(root)) {
2333                 ret = PTR_ERR(root);
2334                 if (ret != -ENOENT)
2335                         goto out;
2336         } else {
2337                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2338                 fs_info->uuid_root = root;
2339         }
2340
2341         if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
2342                 location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID;
2343                 root = btrfs_read_tree_root(tree_root, &location);
2344                 if (IS_ERR(root)) {
2345                         ret = PTR_ERR(root);
2346                         goto out;
2347                 }
2348                 set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2349                 fs_info->free_space_root = root;
2350         }
2351
2352         return 0;
2353 out:
2354         btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2355                    location.objectid, ret);
2356         return ret;
2357 }
2358
2359 /*
2360  * Real super block validation
2361  * NOTE: super csum type and incompat features will not be checked here.
2362  *
2363  * @sb:         super block to check
2364  * @mirror_num: the super block number to check its bytenr:
2365  *              0       the primary (1st) sb
2366  *              1, 2    2nd and 3rd backup copy
2367  *             -1       skip bytenr check
2368  */
2369 static int validate_super(struct btrfs_fs_info *fs_info,
2370                             struct btrfs_super_block *sb, int mirror_num)
2371 {
2372         u64 nodesize = btrfs_super_nodesize(sb);
2373         u64 sectorsize = btrfs_super_sectorsize(sb);
2374         int ret = 0;
2375
2376         if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2377                 btrfs_err(fs_info, "no valid FS found");
2378                 ret = -EINVAL;
2379         }
2380         if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2381                 btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2382                                 btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2383                 ret = -EINVAL;
2384         }
2385         if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2386                 btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2387                                 btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2388                 ret = -EINVAL;
2389         }
2390         if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2391                 btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2392                                 btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2393                 ret = -EINVAL;
2394         }
2395         if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2396                 btrfs_err(fs_info, "log_root level too big: %d >= %d",
2397                                 btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2398                 ret = -EINVAL;
2399         }
2400
2401         /*
2402          * Check sectorsize and nodesize first, other check will need it.
2403          * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2404          */
2405         if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2406             sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2407                 btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2408                 ret = -EINVAL;
2409         }
2410         /* Only PAGE SIZE is supported yet */
2411         if (sectorsize != PAGE_SIZE) {
2412                 btrfs_err(fs_info,
2413                         "sectorsize %llu not supported yet, only support %lu",
2414                         sectorsize, PAGE_SIZE);
2415                 ret = -EINVAL;
2416         }
2417         if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2418             nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2419                 btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2420                 ret = -EINVAL;
2421         }
2422         if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2423                 btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2424                           le32_to_cpu(sb->__unused_leafsize), nodesize);
2425                 ret = -EINVAL;
2426         }
2427
2428         /* Root alignment check */
2429         if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2430                 btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2431                            btrfs_super_root(sb));
2432                 ret = -EINVAL;
2433         }
2434         if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2435                 btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2436                            btrfs_super_chunk_root(sb));
2437                 ret = -EINVAL;
2438         }
2439         if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2440                 btrfs_warn(fs_info, "log_root block unaligned: %llu",
2441                            btrfs_super_log_root(sb));
2442                 ret = -EINVAL;
2443         }
2444
2445         if (memcmp(fs_info->fsid, sb->dev_item.fsid, BTRFS_FSID_SIZE) != 0) {
2446                 btrfs_err(fs_info,
2447                            "dev_item UUID does not match fsid: %pU != %pU",
2448                            fs_info->fsid, sb->dev_item.fsid);
2449                 ret = -EINVAL;
2450         }
2451
2452         /*
2453          * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2454          * done later
2455          */
2456         if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2457                 btrfs_err(fs_info, "bytes_used is too small %llu",
2458                           btrfs_super_bytes_used(sb));
2459                 ret = -EINVAL;
2460         }
2461         if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2462                 btrfs_err(fs_info, "invalid stripesize %u",
2463                           btrfs_super_stripesize(sb));
2464                 ret = -EINVAL;
2465         }
2466         if (btrfs_super_num_devices(sb) > (1UL << 31))
2467                 btrfs_warn(fs_info, "suspicious number of devices: %llu",
2468                            btrfs_super_num_devices(sb));
2469         if (btrfs_super_num_devices(sb) == 0) {
2470                 btrfs_err(fs_info, "number of devices is 0");
2471                 ret = -EINVAL;
2472         }
2473
2474         if (mirror_num >= 0 &&
2475             btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2476                 btrfs_err(fs_info, "super offset mismatch %llu != %u",
2477                           btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2478                 ret = -EINVAL;
2479         }
2480
2481         /*
2482          * Obvious sys_chunk_array corruptions, it must hold at least one key
2483          * and one chunk
2484          */
2485         if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2486                 btrfs_err(fs_info, "system chunk array too big %u > %u",
2487                           btrfs_super_sys_array_size(sb),
2488                           BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2489                 ret = -EINVAL;
2490         }
2491         if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2492                         + sizeof(struct btrfs_chunk)) {
2493                 btrfs_err(fs_info, "system chunk array too small %u < %zu",
2494                           btrfs_super_sys_array_size(sb),
2495                           sizeof(struct btrfs_disk_key)
2496                           + sizeof(struct btrfs_chunk));
2497                 ret = -EINVAL;
2498         }
2499
2500         /*
2501          * The generation is a global counter, we'll trust it more than the others
2502          * but it's still possible that it's the one that's wrong.
2503          */
2504         if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2505                 btrfs_warn(fs_info,
2506                         "suspicious: generation < chunk_root_generation: %llu < %llu",
2507                         btrfs_super_generation(sb),
2508                         btrfs_super_chunk_root_generation(sb));
2509         if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2510             && btrfs_super_cache_generation(sb) != (u64)-1)
2511                 btrfs_warn(fs_info,
2512                         "suspicious: generation < cache_generation: %llu < %llu",
2513                         btrfs_super_generation(sb),
2514                         btrfs_super_cache_generation(sb));
2515
2516         return ret;
2517 }
2518
2519 /*
2520  * Validation of super block at mount time.
2521  * Some checks already done early at mount time, like csum type and incompat
2522  * flags will be skipped.
2523  */
2524 static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2525 {
2526         return validate_super(fs_info, fs_info->super_copy, 0);
2527 }
2528
2529 /*
2530  * Validation of super block at write time.
2531  * Some checks like bytenr check will be skipped as their values will be
2532  * overwritten soon.
2533  * Extra checks like csum type and incompat flags will be done here.
2534  */
2535 static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2536                                       struct btrfs_super_block *sb)
2537 {
2538         int ret;
2539
2540         ret = validate_super(fs_info, sb, -1);
2541         if (ret < 0)
2542                 goto out;
2543         if (btrfs_super_csum_type(sb) != BTRFS_CSUM_TYPE_CRC32) {
2544                 ret = -EUCLEAN;
2545                 btrfs_err(fs_info, "invalid csum type, has %u want %u",
2546                           btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2547                 goto out;
2548         }
2549         if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2550                 ret = -EUCLEAN;
2551                 btrfs_err(fs_info,
2552                 "invalid incompat flags, has 0x%llx valid mask 0x%llx",
2553                           btrfs_super_incompat_flags(sb),
2554                           (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2555                 goto out;
2556         }
2557 out:
2558         if (ret < 0)
2559                 btrfs_err(fs_info,
2560                 "super block corruption detected before writing it to disk");
2561         return ret;
2562 }
2563
2564 int open_ctree(struct super_block *sb,
2565                struct btrfs_fs_devices *fs_devices,
2566                char *options)
2567 {
2568         u32 sectorsize;
2569         u32 nodesize;
2570         u32 stripesize;
2571         u64 generation;
2572         u64 features;
2573         struct btrfs_key location;
2574         struct buffer_head *bh;
2575         struct btrfs_super_block *disk_super;
2576         struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2577         struct btrfs_root *tree_root;
2578         struct btrfs_root *chunk_root;
2579         int ret;
2580         int err = -EINVAL;
2581         int num_backups_tried = 0;
2582         int backup_index = 0;
2583         int clear_free_space_tree = 0;
2584         int level;
2585
2586         tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2587         chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2588         if (!tree_root || !chunk_root) {
2589                 err = -ENOMEM;
2590                 goto fail;
2591         }
2592
2593         ret = init_srcu_struct(&fs_info->subvol_srcu);
2594         if (ret) {
2595                 err = ret;
2596                 goto fail;
2597         }
2598
2599         ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
2600         if (ret) {
2601                 err = ret;
2602                 goto fail_srcu;
2603         }
2604         fs_info->dirty_metadata_batch = PAGE_SIZE *
2605                                         (1 + ilog2(nr_cpu_ids));
2606
2607         ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
2608         if (ret) {
2609                 err = ret;
2610                 goto fail_dirty_metadata_bytes;
2611         }
2612
2613         ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
2614                         GFP_KERNEL);
2615         if (ret) {
2616                 err = ret;
2617                 goto fail_delalloc_bytes;
2618         }
2619
2620         INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2621         INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2622         INIT_LIST_HEAD(&fs_info->trans_list);
2623         INIT_LIST_HEAD(&fs_info->dead_roots);
2624         INIT_LIST_HEAD(&fs_info->delayed_iputs);
2625         INIT_LIST_HEAD(&fs_info->delalloc_roots);
2626         INIT_LIST_HEAD(&fs_info->caching_block_groups);
2627         INIT_LIST_HEAD(&fs_info->pending_raid_kobjs);
2628         spin_lock_init(&fs_info->pending_raid_kobjs_lock);
2629         spin_lock_init(&fs_info->delalloc_root_lock);
2630         spin_lock_init(&fs_info->trans_lock);
2631         spin_lock_init(&fs_info->fs_roots_radix_lock);
2632         spin_lock_init(&fs_info->delayed_iput_lock);
2633         spin_lock_init(&fs_info->defrag_inodes_lock);
2634         spin_lock_init(&fs_info->tree_mod_seq_lock);
2635         spin_lock_init(&fs_info->super_lock);
2636         spin_lock_init(&fs_info->qgroup_op_lock);
2637         spin_lock_init(&fs_info->buffer_lock);
2638         spin_lock_init(&fs_info->unused_bgs_lock);
2639         rwlock_init(&fs_info->tree_mod_log_lock);
2640         mutex_init(&fs_info->unused_bg_unpin_mutex);
2641         mutex_init(&fs_info->delete_unused_bgs_mutex);
2642         mutex_init(&fs_info->reloc_mutex);
2643         mutex_init(&fs_info->delalloc_root_mutex);
2644         mutex_init(&fs_info->cleaner_delayed_iput_mutex);
2645         seqlock_init(&fs_info->profiles_lock);
2646
2647         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2648         INIT_LIST_HEAD(&fs_info->space_info);
2649         INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2650         INIT_LIST_HEAD(&fs_info->unused_bgs);
2651         btrfs_mapping_init(&fs_info->mapping_tree);
2652         btrfs_init_block_rsv(&fs_info->global_block_rsv,
2653                              BTRFS_BLOCK_RSV_GLOBAL);
2654         btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2655         btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2656         btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2657         btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2658                              BTRFS_BLOCK_RSV_DELOPS);
2659         atomic_set(&fs_info->async_delalloc_pages, 0);
2660         atomic_set(&fs_info->defrag_running, 0);
2661         atomic_set(&fs_info->qgroup_op_seq, 0);
2662         atomic_set(&fs_info->reada_works_cnt, 0);
2663         atomic64_set(&fs_info->tree_mod_seq, 0);
2664         fs_info->sb = sb;
2665         fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2666         fs_info->metadata_ratio = 0;
2667         fs_info->defrag_inodes = RB_ROOT;
2668         atomic64_set(&fs_info->free_chunk_space, 0);
2669         fs_info->tree_mod_log = RB_ROOT;
2670         fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2671         fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
2672         /* readahead state */
2673         INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
2674         spin_lock_init(&fs_info->reada_lock);
2675         btrfs_init_ref_verify(fs_info);
2676
2677         fs_info->thread_pool_size = min_t(unsigned long,
2678                                           num_online_cpus() + 2, 8);
2679
2680         INIT_LIST_HEAD(&fs_info->ordered_roots);
2681         spin_lock_init(&fs_info->ordered_root_lock);
2682
2683         fs_info->btree_inode = new_inode(sb);
2684         if (!fs_info->btree_inode) {
2685                 err = -ENOMEM;
2686                 goto fail_bio_counter;
2687         }
2688         mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
2689
2690         fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2691                                         GFP_KERNEL);
2692         if (!fs_info->delayed_root) {
2693                 err = -ENOMEM;
2694                 goto fail_iput;
2695         }
2696         btrfs_init_delayed_root(fs_info->delayed_root);
2697
2698         btrfs_init_scrub(fs_info);
2699 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2700         fs_info->check_integrity_print_mask = 0;
2701 #endif
2702         btrfs_init_balance(fs_info);
2703         btrfs_init_async_reclaim_work(&fs_info->async_reclaim_work);
2704
2705         sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
2706         sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
2707
2708         btrfs_init_btree_inode(fs_info);
2709
2710         spin_lock_init(&fs_info->block_group_cache_lock);
2711         fs_info->block_group_cache_tree = RB_ROOT;
2712         fs_info->first_logical_byte = (u64)-1;
2713
2714         extent_io_tree_init(&fs_info->freed_extents[0], NULL);
2715         extent_io_tree_init(&fs_info->freed_extents[1], NULL);
2716         fs_info->pinned_extents = &fs_info->freed_extents[0];
2717         set_bit(BTRFS_FS_BARRIER, &fs_info->flags);
2718
2719         mutex_init(&fs_info->ordered_operations_mutex);
2720         mutex_init(&fs_info->tree_log_mutex);
2721         mutex_init(&fs_info->chunk_mutex);
2722         mutex_init(&fs_info->transaction_kthread_mutex);
2723         mutex_init(&fs_info->cleaner_mutex);
2724         mutex_init(&fs_info->ro_block_group_mutex);
2725         init_rwsem(&fs_info->commit_root_sem);
2726         init_rwsem(&fs_info->cleanup_work_sem);
2727         init_rwsem(&fs_info->subvol_sem);
2728         sema_init(&fs_info->uuid_tree_rescan_sem, 1);
2729
2730         btrfs_init_dev_replace_locks(fs_info);
2731         btrfs_init_qgroup(fs_info);
2732
2733         btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2734         btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2735
2736         init_waitqueue_head(&fs_info->transaction_throttle);
2737         init_waitqueue_head(&fs_info->transaction_wait);
2738         init_waitqueue_head(&fs_info->transaction_blocked_wait);
2739         init_waitqueue_head(&fs_info->async_submit_wait);
2740
2741         INIT_LIST_HEAD(&fs_info->pinned_chunks);
2742
2743         /* Usable values until the real ones are cached from the superblock */
2744         fs_info->nodesize = 4096;
2745         fs_info->sectorsize = 4096;
2746         fs_info->stripesize = 4096;
2747
2748         ret = btrfs_alloc_stripe_hash_table(fs_info);
2749         if (ret) {
2750                 err = ret;
2751                 goto fail_alloc;
2752         }
2753
2754         __setup_root(tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
2755
2756         invalidate_bdev(fs_devices->latest_bdev);
2757
2758         /*
2759          * Read super block and check the signature bytes only
2760          */
2761         bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2762         if (IS_ERR(bh)) {
2763                 err = PTR_ERR(bh);
2764                 goto fail_alloc;
2765         }
2766
2767         /*
2768          * We want to check superblock checksum, the type is stored inside.
2769          * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
2770          */
2771         if (btrfs_check_super_csum(fs_info, bh->b_data)) {
2772                 btrfs_err(fs_info, "superblock checksum mismatch");
2773                 err = -EINVAL;
2774                 brelse(bh);
2775                 goto fail_alloc;
2776         }
2777
2778         /*
2779          * super_copy is zeroed at allocation time and we never touch the
2780          * following bytes up to INFO_SIZE, the checksum is calculated from
2781          * the whole block of INFO_SIZE
2782          */
2783         memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
2784         memcpy(fs_info->super_for_commit, fs_info->super_copy,
2785                sizeof(*fs_info->super_for_commit));
2786         brelse(bh);
2787
2788         memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
2789
2790         ret = btrfs_validate_mount_super(fs_info);
2791         if (ret) {
2792                 btrfs_err(fs_info, "superblock contains fatal errors");
2793                 err = -EINVAL;
2794                 goto fail_alloc;
2795         }
2796
2797         disk_super = fs_info->super_copy;
2798         if (!btrfs_super_root(disk_super))
2799                 goto fail_alloc;
2800
2801         /* check FS state, whether FS is broken. */
2802         if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
2803                 set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
2804
2805         /*
2806          * run through our array of backup supers and setup
2807          * our ring pointer to the oldest one
2808          */
2809         generation = btrfs_super_generation(disk_super);
2810         find_oldest_super_backup(fs_info, generation);
2811
2812         /*
2813          * In the long term, we'll store the compression type in the super
2814          * block, and it'll be used for per file compression control.
2815          */
2816         fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2817
2818         ret = btrfs_parse_options(fs_info, options, sb->s_flags);
2819         if (ret) {
2820                 err = ret;
2821                 goto fail_alloc;
2822         }
2823
2824         features = btrfs_super_incompat_flags(disk_super) &
2825                 ~BTRFS_FEATURE_INCOMPAT_SUPP;
2826         if (features) {
2827                 btrfs_err(fs_info,
2828                     "cannot mount because of unsupported optional features (%llx)",
2829                     features);
2830                 err = -EINVAL;
2831                 goto fail_alloc;
2832         }
2833
2834         features = btrfs_super_incompat_flags(disk_super);
2835         features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2836         if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
2837                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
2838         else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
2839                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
2840
2841         if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
2842                 btrfs_info(fs_info, "has skinny extents");
2843
2844         /*
2845          * flag our filesystem as having big metadata blocks if
2846          * they are bigger than the page size
2847          */
2848         if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
2849                 if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
2850                         btrfs_info(fs_info,
2851                                 "flagging fs with big metadata feature");
2852                 features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
2853         }
2854
2855         nodesize = btrfs_super_nodesize(disk_super);
2856         sectorsize = btrfs_super_sectorsize(disk_super);
2857         stripesize = sectorsize;
2858         fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
2859         fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
2860
2861         /* Cache block sizes */
2862         fs_info->nodesize = nodesize;
2863         fs_info->sectorsize = sectorsize;
2864         fs_info->stripesize = stripesize;
2865
2866         /*
2867          * mixed block groups end up with duplicate but slightly offset
2868          * extent buffers for the same range.  It leads to corruptions
2869          */
2870         if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2871             (sectorsize != nodesize)) {
2872                 btrfs_err(fs_info,
2873 "unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
2874                         nodesize, sectorsize);
2875                 goto fail_alloc;
2876         }
2877
2878         /*
2879          * Needn't use the lock because there is no other task which will
2880          * update the flag.
2881          */
2882         btrfs_set_super_incompat_flags(disk_super, features);
2883
2884         features = btrfs_super_compat_ro_flags(disk_super) &
2885                 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
2886         if (!sb_rdonly(sb) && features) {
2887                 btrfs_err(fs_info,
2888         "cannot mount read-write because of unsupported optional features (%llx)",
2889                        features);
2890                 err = -EINVAL;
2891                 goto fail_alloc;
2892         }
2893
2894         ret = btrfs_init_workqueues(fs_info, fs_devices);
2895         if (ret) {
2896                 err = ret;
2897                 goto fail_sb_buffer;
2898         }
2899
2900         sb->s_bdi->congested_fn = btrfs_congested_fn;
2901         sb->s_bdi->congested_data = fs_info;
2902         sb->s_bdi->capabilities |= BDI_CAP_CGROUP_WRITEBACK;
2903         sb->s_bdi->ra_pages = VM_MAX_READAHEAD * SZ_1K / PAGE_SIZE;
2904         sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
2905         sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
2906
2907         sb->s_blocksize = sectorsize;
2908         sb->s_blocksize_bits = blksize_bits(sectorsize);
2909         memcpy(&sb->s_uuid, fs_info->fsid, BTRFS_FSID_SIZE);
2910
2911         mutex_lock(&fs_info->chunk_mutex);
2912         ret = btrfs_read_sys_array(fs_info);
2913         mutex_unlock(&fs_info->chunk_mutex);
2914         if (ret) {
2915                 btrfs_err(fs_info, "failed to read the system array: %d", ret);
2916                 goto fail_sb_buffer;
2917         }
2918
2919         generation = btrfs_super_chunk_root_generation(disk_super);
2920         level = btrfs_super_chunk_root_level(disk_super);
2921
2922         __setup_root(chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2923
2924         chunk_root->node = read_tree_block(fs_info,
2925                                            btrfs_super_chunk_root(disk_super),
2926                                            generation, level, NULL);
2927         if (IS_ERR(chunk_root->node) ||
2928             !extent_buffer_uptodate(chunk_root->node)) {
2929                 btrfs_err(fs_info, "failed to read chunk root");
2930                 if (!IS_ERR(chunk_root->node))
2931                         free_extent_buffer(chunk_root->node);
2932                 chunk_root->node = NULL;
2933                 goto fail_tree_roots;
2934         }
2935         btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
2936         chunk_root->commit_root = btrfs_root_node(chunk_root);
2937
2938         read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
2939            btrfs_header_chunk_tree_uuid(chunk_root->node), BTRFS_UUID_SIZE);
2940
2941         ret = btrfs_read_chunk_tree(fs_info);
2942         if (ret) {
2943                 btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
2944                 goto fail_tree_roots;
2945         }
2946
2947         /*
2948          * Keep the devid that is marked to be the target device for the
2949          * device replace procedure
2950          */
2951         btrfs_free_extra_devids(fs_devices, 0);
2952
2953         if (!fs_devices->latest_bdev) {
2954                 btrfs_err(fs_info, "failed to read devices");
2955                 goto fail_tree_roots;
2956         }
2957
2958 retry_root_backup:
2959         generation = btrfs_super_generation(disk_super);
2960         level = btrfs_super_root_level(disk_super);
2961
2962         tree_root->node = read_tree_block(fs_info,
2963                                           btrfs_super_root(disk_super),
2964                                           generation, level, NULL);
2965         if (IS_ERR(tree_root->node) ||
2966             !extent_buffer_uptodate(tree_root->node)) {
2967                 btrfs_warn(fs_info, "failed to read tree root");
2968                 if (!IS_ERR(tree_root->node))
2969                         free_extent_buffer(tree_root->node);
2970                 tree_root->node = NULL;
2971                 goto recovery_tree_root;
2972         }
2973
2974         btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2975         tree_root->commit_root = btrfs_root_node(tree_root);
2976         btrfs_set_root_refs(&tree_root->root_item, 1);
2977
2978         mutex_lock(&tree_root->objectid_mutex);
2979         ret = btrfs_find_highest_objectid(tree_root,
2980                                         &tree_root->highest_objectid);
2981         if (ret) {
2982                 mutex_unlock(&tree_root->objectid_mutex);
2983                 goto recovery_tree_root;
2984         }
2985
2986         ASSERT(tree_root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
2987
2988         mutex_unlock(&tree_root->objectid_mutex);
2989
2990         ret = btrfs_read_roots(fs_info);
2991         if (ret)
2992                 goto recovery_tree_root;
2993
2994         fs_info->generation = generation;
2995         fs_info->last_trans_committed = generation;
2996
2997         ret = btrfs_verify_dev_extents(fs_info);
2998         if (ret) {
2999                 btrfs_err(fs_info,
3000                           "failed to verify dev extents against chunks: %d",
3001                           ret);
3002                 goto fail_block_groups;
3003         }
3004         ret = btrfs_recover_balance(fs_info);
3005         if (ret) {
3006                 btrfs_err(fs_info, "failed to recover balance: %d", ret);
3007                 goto fail_block_groups;
3008         }
3009
3010         ret = btrfs_init_dev_stats(fs_info);
3011         if (ret) {
3012                 btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3013                 goto fail_block_groups;
3014         }
3015
3016         ret = btrfs_init_dev_replace(fs_info);
3017         if (ret) {
3018                 btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3019                 goto fail_block_groups;
3020         }
3021
3022         btrfs_free_extra_devids(fs_devices, 1);
3023
3024         ret = btrfs_sysfs_add_fsid(fs_devices, NULL);
3025         if (ret) {
3026                 btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3027                                 ret);
3028                 goto fail_block_groups;
3029         }
3030
3031         ret = btrfs_sysfs_add_device(fs_devices);
3032         if (ret) {
3033                 btrfs_err(fs_info, "failed to init sysfs device interface: %d",
3034                                 ret);
3035                 goto fail_fsdev_sysfs;
3036         }
3037
3038         ret = btrfs_sysfs_add_mounted(fs_info);
3039         if (ret) {
3040                 btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3041                 goto fail_fsdev_sysfs;
3042         }
3043
3044         ret = btrfs_init_space_info(fs_info);
3045         if (ret) {
3046                 btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3047                 goto fail_sysfs;
3048         }
3049
3050         ret = btrfs_read_block_groups(fs_info);
3051         if (ret) {
3052                 btrfs_err(fs_info, "failed to read block groups: %d", ret);
3053                 goto fail_sysfs;
3054         }
3055
3056         if (!sb_rdonly(sb) && !btrfs_check_rw_degradable(fs_info, NULL)) {
3057                 btrfs_warn(fs_info,
3058                 "writeable mount is not allowed due to too many missing devices");
3059                 goto fail_sysfs;
3060         }
3061
3062         fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
3063                                                "btrfs-cleaner");
3064         if (IS_ERR(fs_info->cleaner_kthread))
3065                 goto fail_sysfs;
3066
3067         fs_info->transaction_kthread = kthread_run(transaction_kthread,
3068                                                    tree_root,
3069                                                    "btrfs-transaction");
3070         if (IS_ERR(fs_info->transaction_kthread))
3071                 goto fail_cleaner;
3072
3073         if (!btrfs_test_opt(fs_info, NOSSD) &&
3074             !fs_info->fs_devices->rotating) {
3075                 btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations");
3076         }
3077
3078         /*
3079          * Mount does not set all options immediately, we can do it now and do
3080          * not have to wait for transaction commit
3081          */
3082         btrfs_apply_pending_changes(fs_info);
3083
3084 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3085         if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) {
3086                 ret = btrfsic_mount(fs_info, fs_devices,
3087                                     btrfs_test_opt(fs_info,
3088                                         CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
3089                                     1 : 0,
3090                                     fs_info->check_integrity_print_mask);
3091                 if (ret)
3092                         btrfs_warn(fs_info,
3093                                 "failed to initialize integrity check module: %d",
3094                                 ret);
3095         }
3096 #endif
3097         ret = btrfs_read_qgroup_config(fs_info);
3098         if (ret)
3099                 goto fail_trans_kthread;
3100
3101         if (btrfs_build_ref_tree(fs_info))
3102                 btrfs_err(fs_info, "couldn't build ref tree");
3103
3104         /* do not make disk changes in broken FS or nologreplay is given */
3105         if (btrfs_super_log_root(disk_super) != 0 &&
3106             !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3107                 ret = btrfs_replay_log(fs_info, fs_devices);
3108                 if (ret) {
3109                         err = ret;
3110                         goto fail_qgroup;
3111                 }
3112         }
3113
3114         ret = btrfs_find_orphan_roots(fs_info);
3115         if (ret)
3116                 goto fail_qgroup;
3117
3118         if (!sb_rdonly(sb)) {
3119                 ret = btrfs_cleanup_fs_roots(fs_info);
3120                 if (ret)
3121                         goto fail_qgroup;
3122
3123                 mutex_lock(&fs_info->cleaner_mutex);
3124                 ret = btrfs_recover_relocation(tree_root);
3125                 mutex_unlock(&fs_info->cleaner_mutex);
3126                 if (ret < 0) {
3127                         btrfs_warn(fs_info, "failed to recover relocation: %d",
3128                                         ret);
3129                         err = -EINVAL;
3130                         goto fail_qgroup;
3131                 }
3132         }
3133
3134         location.objectid = BTRFS_FS_TREE_OBJECTID;
3135         location.type = BTRFS_ROOT_ITEM_KEY;
3136         location.offset = 0;
3137
3138         fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
3139         if (IS_ERR(fs_info->fs_root)) {
3140                 err = PTR_ERR(fs_info->fs_root);
3141                 btrfs_warn(fs_info, "failed to read fs tree: %d", err);
3142                 goto fail_qgroup;
3143         }
3144
3145         if (sb_rdonly(sb))
3146                 return 0;
3147
3148         if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3149             btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3150                 clear_free_space_tree = 1;
3151         } else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3152                    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3153                 btrfs_warn(fs_info, "free space tree is invalid");
3154                 clear_free_space_tree = 1;
3155         }
3156
3157         if (clear_free_space_tree) {
3158                 btrfs_info(fs_info, "clearing free space tree");
3159                 ret = btrfs_clear_free_space_tree(fs_info);
3160                 if (ret) {
3161                         btrfs_warn(fs_info,
3162                                    "failed to clear free space tree: %d", ret);
3163                         close_ctree(fs_info);
3164                         return ret;
3165                 }
3166         }
3167
3168         if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3169             !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3170                 btrfs_info(fs_info, "creating free space tree");
3171                 ret = btrfs_create_free_space_tree(fs_info);
3172                 if (ret) {
3173                         btrfs_warn(fs_info,
3174                                 "failed to create free space tree: %d", ret);
3175                         close_ctree(fs_info);
3176                         return ret;
3177                 }
3178         }
3179
3180         down_read(&fs_info->cleanup_work_sem);
3181         if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3182             (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3183                 up_read(&fs_info->cleanup_work_sem);
3184                 close_ctree(fs_info);
3185                 return ret;
3186         }
3187         up_read(&fs_info->cleanup_work_sem);
3188
3189         ret = btrfs_resume_balance_async(fs_info);
3190         if (ret) {
3191                 btrfs_warn(fs_info, "failed to resume balance: %d", ret);
3192                 close_ctree(fs_info);
3193                 return ret;
3194         }
3195
3196         ret = btrfs_resume_dev_replace_async(fs_info);
3197         if (ret) {
3198                 btrfs_warn(fs_info, "failed to resume device replace: %d", ret);
3199                 close_ctree(fs_info);
3200                 return ret;
3201         }
3202
3203         btrfs_qgroup_rescan_resume(fs_info);
3204
3205         if (!fs_info->uuid_root) {
3206                 btrfs_info(fs_info, "creating UUID tree");
3207                 ret = btrfs_create_uuid_tree(fs_info);
3208                 if (ret) {
3209                         btrfs_warn(fs_info,
3210                                 "failed to create the UUID tree: %d", ret);
3211                         close_ctree(fs_info);
3212                         return ret;
3213                 }
3214         } else if (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3215                    fs_info->generation !=
3216                                 btrfs_super_uuid_tree_generation(disk_super)) {
3217                 btrfs_info(fs_info, "checking UUID tree");
3218                 ret = btrfs_check_uuid_tree(fs_info);
3219                 if (ret) {
3220                         btrfs_warn(fs_info,
3221                                 "failed to check the UUID tree: %d", ret);
3222                         close_ctree(fs_info);
3223                         return ret;
3224                 }
3225         } else {
3226                 set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3227         }
3228         set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3229
3230         /*
3231          * backuproot only affect mount behavior, and if open_ctree succeeded,
3232          * no need to keep the flag
3233          */
3234         btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3235
3236         return 0;
3237
3238 fail_qgroup:
3239         btrfs_free_qgroup_config(fs_info);
3240 fail_trans_kthread:
3241         kthread_stop(fs_info->transaction_kthread);
3242         btrfs_cleanup_transaction(fs_info);
3243         btrfs_free_fs_roots(fs_info);
3244 fail_cleaner:
3245         kthread_stop(fs_info->cleaner_kthread);
3246
3247         /*
3248          * make sure we're done with the btree inode before we stop our
3249          * kthreads
3250          */
3251         filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3252
3253 fail_sysfs:
3254         btrfs_sysfs_remove_mounted(fs_info);
3255
3256 fail_fsdev_sysfs:
3257         btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3258
3259 fail_block_groups:
3260         btrfs_put_block_group_cache(fs_info);
3261
3262 fail_tree_roots: