1
2
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4
5
6#include <linux/fs.h>
7#include <linux/slab.h>
8#include <linux/sched.h>
9#include <linux/writeback.h>
10#include <linux/pagemap.h>
11#include <linux/blkdev.h>
12#include <linux/uuid.h>
13#include "ctree.h"
14#include "disk-io.h"
15#include "transaction.h"
16#include "locking.h"
17#include "tree-log.h"
18#include "inode-map.h"
19#include "volumes.h"
20#include "dev-replace.h"
21#include "qgroup.h"
22
23#define BTRFS_ROOT_TRANS_TAG 0
24
25static const unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = {
26 [TRANS_STATE_RUNNING] = 0U,
27 [TRANS_STATE_BLOCKED] = __TRANS_START,
28 [TRANS_STATE_COMMIT_START] = (__TRANS_START | __TRANS_ATTACH),
29 [TRANS_STATE_COMMIT_DOING] = (__TRANS_START |
30 __TRANS_ATTACH |
31 __TRANS_JOIN |
32 __TRANS_JOIN_NOSTART),
33 [TRANS_STATE_UNBLOCKED] = (__TRANS_START |
34 __TRANS_ATTACH |
35 __TRANS_JOIN |
36 __TRANS_JOIN_NOLOCK |
37 __TRANS_JOIN_NOSTART),
38 [TRANS_STATE_COMPLETED] = (__TRANS_START |
39 __TRANS_ATTACH |
40 __TRANS_JOIN |
41 __TRANS_JOIN_NOLOCK |
42 __TRANS_JOIN_NOSTART),
43};
44
45void btrfs_put_transaction(struct btrfs_transaction *transaction)
46{
47 WARN_ON(refcount_read(&transaction->use_count) == 0);
48 if (refcount_dec_and_test(&transaction->use_count)) {
49 BUG_ON(!list_empty(&transaction->list));
50 WARN_ON(!RB_EMPTY_ROOT(
51 &transaction->delayed_refs.href_root.rb_root));
52 if (transaction->delayed_refs.pending_csums)
53 btrfs_err(transaction->fs_info,
54 "pending csums is %llu",
55 transaction->delayed_refs.pending_csums);
56
57
58
59
60
61
62
63 while (!list_empty(&transaction->deleted_bgs)) {
64 struct btrfs_block_group_cache *cache;
65
66 cache = list_first_entry(&transaction->deleted_bgs,
67 struct btrfs_block_group_cache,
68 bg_list);
69 list_del_init(&cache->bg_list);
70 btrfs_put_block_group_trimming(cache);
71 btrfs_put_block_group(cache);
72 }
73 WARN_ON(!list_empty(&transaction->dev_update_list));
74 kfree(transaction);
75 }
76}
77
78static noinline void switch_commit_roots(struct btrfs_transaction *trans)
79{
80 struct btrfs_fs_info *fs_info = trans->fs_info;
81 struct btrfs_root *root, *tmp;
82
83 down_write(&fs_info->commit_root_sem);
84 list_for_each_entry_safe(root, tmp, &trans->switch_commits,
85 dirty_list) {
86 list_del_init(&root->dirty_list);
87 free_extent_buffer(root->commit_root);
88 root->commit_root = btrfs_root_node(root);
89 if (is_fstree(root->root_key.objectid))
90 btrfs_unpin_free_ino(root);
91 extent_io_tree_release(&root->dirty_log_pages);
92 btrfs_qgroup_clean_swapped_blocks(root);
93 }
94
95
96 spin_lock(&trans->dropped_roots_lock);
97 while (!list_empty(&trans->dropped_roots)) {
98 root = list_first_entry(&trans->dropped_roots,
99 struct btrfs_root, root_list);
100 list_del_init(&root->root_list);
101 spin_unlock(&trans->dropped_roots_lock);
102 btrfs_drop_and_free_fs_root(fs_info, root);
103 spin_lock(&trans->dropped_roots_lock);
104 }
105 spin_unlock(&trans->dropped_roots_lock);
106 up_write(&fs_info->commit_root_sem);
107}
108
109static inline void extwriter_counter_inc(struct btrfs_transaction *trans,
110 unsigned int type)
111{
112 if (type & TRANS_EXTWRITERS)
113 atomic_inc(&trans->num_extwriters);
114}
115
116static inline void extwriter_counter_dec(struct btrfs_transaction *trans,
117 unsigned int type)
118{
119 if (type & TRANS_EXTWRITERS)
120 atomic_dec(&trans->num_extwriters);
121}
122
123static inline void extwriter_counter_init(struct btrfs_transaction *trans,
124 unsigned int type)
125{
126 atomic_set(&trans->num_extwriters, ((type & TRANS_EXTWRITERS) ? 1 : 0));
127}
128
129static inline int extwriter_counter_read(struct btrfs_transaction *trans)
130{
131 return atomic_read(&trans->num_extwriters);
132}
133
134
135
136
137
138void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
139{
140 struct btrfs_fs_info *fs_info = trans->fs_info;
141
142 if (!trans->chunk_bytes_reserved)
143 return;
144
145 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
146
147 btrfs_block_rsv_release(fs_info, &fs_info->chunk_block_rsv,
148 trans->chunk_bytes_reserved);
149 trans->chunk_bytes_reserved = 0;
150}
151
152
153
154
155static noinline int join_transaction(struct btrfs_fs_info *fs_info,
156 unsigned int type)
157{
158 struct btrfs_transaction *cur_trans;
159
160 spin_lock(&fs_info->trans_lock);
161loop:
162
163 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
164 spin_unlock(&fs_info->trans_lock);
165 return -EROFS;
166 }
167
168 cur_trans = fs_info->running_transaction;
169 if (cur_trans) {
170 if (cur_trans->aborted) {
171 spin_unlock(&fs_info->trans_lock);
172 return cur_trans->aborted;
173 }
174 if (btrfs_blocked_trans_types[cur_trans->state] & type) {
175 spin_unlock(&fs_info->trans_lock);
176 return -EBUSY;
177 }
178 refcount_inc(&cur_trans->use_count);
179 atomic_inc(&cur_trans->num_writers);
180 extwriter_counter_inc(cur_trans, type);
181 spin_unlock(&fs_info->trans_lock);
182 return 0;
183 }
184 spin_unlock(&fs_info->trans_lock);
185
186
187
188
189
190 if (type == TRANS_ATTACH)
191 return -ENOENT;
192
193
194
195
196
197 BUG_ON(type == TRANS_JOIN_NOLOCK);
198
199 cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS);
200 if (!cur_trans)
201 return -ENOMEM;
202
203 spin_lock(&fs_info->trans_lock);
204 if (fs_info->running_transaction) {
205
206
207
208
209 kfree(cur_trans);
210 goto loop;
211 } else if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
212 spin_unlock(&fs_info->trans_lock);
213 kfree(cur_trans);
214 return -EROFS;
215 }
216
217 cur_trans->fs_info = fs_info;
218 atomic_set(&cur_trans->num_writers, 1);
219 extwriter_counter_init(cur_trans, type);
220 init_waitqueue_head(&cur_trans->writer_wait);
221 init_waitqueue_head(&cur_trans->commit_wait);
222 cur_trans->state = TRANS_STATE_RUNNING;
223
224
225
226
227 refcount_set(&cur_trans->use_count, 2);
228 cur_trans->flags = 0;
229 cur_trans->start_time = ktime_get_seconds();
230
231 memset(&cur_trans->delayed_refs, 0, sizeof(cur_trans->delayed_refs));
232
233 cur_trans->delayed_refs.href_root = RB_ROOT_CACHED;
234 cur_trans->delayed_refs.dirty_extent_root = RB_ROOT;
235 atomic_set(&cur_trans->delayed_refs.num_entries, 0);
236
237
238
239
240
241 smp_mb();
242 if (!list_empty(&fs_info->tree_mod_seq_list))
243 WARN(1, KERN_ERR "BTRFS: tree_mod_seq_list not empty when creating a fresh transaction\n");
244 if (!RB_EMPTY_ROOT(&fs_info->tree_mod_log))
245 WARN(1, KERN_ERR "BTRFS: tree_mod_log rb tree not empty when creating a fresh transaction\n");
246 atomic64_set(&fs_info->tree_mod_seq, 0);
247
248 spin_lock_init(&cur_trans->delayed_refs.lock);
249
250 INIT_LIST_HEAD(&cur_trans->pending_snapshots);
251 INIT_LIST_HEAD(&cur_trans->dev_update_list);
252 INIT_LIST_HEAD(&cur_trans->switch_commits);
253 INIT_LIST_HEAD(&cur_trans->dirty_bgs);
254 INIT_LIST_HEAD(&cur_trans->io_bgs);
255 INIT_LIST_HEAD(&cur_trans->dropped_roots);
256 mutex_init(&cur_trans->cache_write_mutex);
257 spin_lock_init(&cur_trans->dirty_bgs_lock);
258 INIT_LIST_HEAD(&cur_trans->deleted_bgs);
259 spin_lock_init(&cur_trans->dropped_roots_lock);
260 list_add_tail(&cur_trans->list, &fs_info->trans_list);
261 extent_io_tree_init(fs_info, &cur_trans->dirty_pages,
262 IO_TREE_TRANS_DIRTY_PAGES, fs_info->btree_inode);
263 fs_info->generation++;
264 cur_trans->transid = fs_info->generation;
265 fs_info->running_transaction = cur_trans;
266 cur_trans->aborted = 0;
267 spin_unlock(&fs_info->trans_lock);
268
269 return 0;
270}
271
272
273
274
275
276
277
278static int record_root_in_trans(struct btrfs_trans_handle *trans,
279 struct btrfs_root *root,
280 int force)
281{
282 struct btrfs_fs_info *fs_info = root->fs_info;
283
284 if ((test_bit(BTRFS_ROOT_REF_COWS, &root->state) &&
285 root->last_trans < trans->transid) || force) {
286 WARN_ON(root == fs_info->extent_root);
287 WARN_ON(!force && root->commit_root != root->node);
288
289
290
291
292
293
294 set_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
295
296
297
298
299 smp_wmb();
300
301 spin_lock(&fs_info->fs_roots_radix_lock);
302 if (root->last_trans == trans->transid && !force) {
303 spin_unlock(&fs_info->fs_roots_radix_lock);
304 return 0;
305 }
306 radix_tree_tag_set(&fs_info->fs_roots_radix,
307 (unsigned long)root->root_key.objectid,
308 BTRFS_ROOT_TRANS_TAG);
309 spin_unlock(&fs_info->fs_roots_radix_lock);
310 root->last_trans = trans->transid;
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331 btrfs_init_reloc_root(trans, root);
332 smp_mb__before_atomic();
333 clear_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
334 }
335 return 0;
336}
337
338
339void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
340 struct btrfs_root *root)
341{
342 struct btrfs_fs_info *fs_info = root->fs_info;
343 struct btrfs_transaction *cur_trans = trans->transaction;
344
345
346 spin_lock(&cur_trans->dropped_roots_lock);
347 list_add_tail(&root->root_list, &cur_trans->dropped_roots);
348 spin_unlock(&cur_trans->dropped_roots_lock);
349
350
351 spin_lock(&fs_info->fs_roots_radix_lock);
352 radix_tree_tag_clear(&fs_info->fs_roots_radix,
353 (unsigned long)root->root_key.objectid,
354 BTRFS_ROOT_TRANS_TAG);
355 spin_unlock(&fs_info->fs_roots_radix_lock);
356}
357
358int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
359 struct btrfs_root *root)
360{
361 struct btrfs_fs_info *fs_info = root->fs_info;
362
363 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
364 return 0;
365
366
367
368
369
370 smp_rmb();
371 if (root->last_trans == trans->transid &&
372 !test_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state))
373 return 0;
374
375 mutex_lock(&fs_info->reloc_mutex);
376 record_root_in_trans(trans, root, 0);
377 mutex_unlock(&fs_info->reloc_mutex);
378
379 return 0;
380}
381
382static inline int is_transaction_blocked(struct btrfs_transaction *trans)
383{
384 return (trans->state >= TRANS_STATE_BLOCKED &&
385 trans->state < TRANS_STATE_UNBLOCKED &&
386 !trans->aborted);
387}
388
389
390
391
392
393static void wait_current_trans(struct btrfs_fs_info *fs_info)
394{
395 struct btrfs_transaction *cur_trans;
396
397 spin_lock(&fs_info->trans_lock);
398 cur_trans = fs_info->running_transaction;
399 if (cur_trans && is_transaction_blocked(cur_trans)) {
400 refcount_inc(&cur_trans->use_count);
401 spin_unlock(&fs_info->trans_lock);
402
403 wait_event(fs_info->transaction_wait,
404 cur_trans->state >= TRANS_STATE_UNBLOCKED ||
405 cur_trans->aborted);
406 btrfs_put_transaction(cur_trans);
407 } else {
408 spin_unlock(&fs_info->trans_lock);
409 }
410}
411
412static int may_wait_transaction(struct btrfs_fs_info *fs_info, int type)
413{
414 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
415 return 0;
416
417 if (type == TRANS_START)
418 return 1;
419
420 return 0;
421}
422
423static inline bool need_reserve_reloc_root(struct btrfs_root *root)
424{
425 struct btrfs_fs_info *fs_info = root->fs_info;
426
427 if (!fs_info->reloc_ctl ||
428 !test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
429 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
430 root->reloc_root)
431 return false;
432
433 return true;
434}
435
436static struct btrfs_trans_handle *
437start_transaction(struct btrfs_root *root, unsigned int num_items,
438 unsigned int type, enum btrfs_reserve_flush_enum flush,
439 bool enforce_qgroups)
440{
441 struct btrfs_fs_info *fs_info = root->fs_info;
442 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
443 struct btrfs_trans_handle *h;
444 struct btrfs_transaction *cur_trans;
445 u64 num_bytes = 0;
446 u64 qgroup_reserved = 0;
447 bool reloc_reserved = false;
448 int ret;
449
450
451 ASSERT(current->journal_info != BTRFS_SEND_TRANS_STUB);
452
453 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
454 return ERR_PTR(-EROFS);
455
456 if (current->journal_info) {
457 WARN_ON(type & TRANS_EXTWRITERS);
458 h = current->journal_info;
459 refcount_inc(&h->use_count);
460 WARN_ON(refcount_read(&h->use_count) > 2);
461 h->orig_rsv = h->block_rsv;
462 h->block_rsv = NULL;
463 goto got_it;
464 }
465
466
467
468
469
470 if (num_items && root != fs_info->chunk_root) {
471 struct btrfs_block_rsv *rsv = &fs_info->trans_block_rsv;
472 u64 delayed_refs_bytes = 0;
473
474 qgroup_reserved = num_items * fs_info->nodesize;
475 ret = btrfs_qgroup_reserve_meta_pertrans(root, qgroup_reserved,
476 enforce_qgroups);
477 if (ret)
478 return ERR_PTR(ret);
479
480
481
482
483
484
485
486
487 num_bytes = btrfs_calc_trans_metadata_size(fs_info, num_items);
488 if (delayed_refs_rsv->full == 0) {
489 delayed_refs_bytes = num_bytes;
490 num_bytes <<= 1;
491 }
492
493
494
495
496 if (need_reserve_reloc_root(root)) {
497 num_bytes += fs_info->nodesize;
498 reloc_reserved = true;
499 }
500
501 ret = btrfs_block_rsv_add(root, rsv, num_bytes, flush);
502 if (ret)
503 goto reserve_fail;
504 if (delayed_refs_bytes) {
505 btrfs_migrate_to_delayed_refs_rsv(fs_info, rsv,
506 delayed_refs_bytes);
507 num_bytes -= delayed_refs_bytes;
508 }
509 } else if (num_items == 0 && flush == BTRFS_RESERVE_FLUSH_ALL &&
510 !delayed_refs_rsv->full) {
511
512
513
514
515
516
517
518 ret = btrfs_delayed_refs_rsv_refill(fs_info, flush);
519 if (ret)
520 goto reserve_fail;
521 }
522again:
523 h = kmem_cache_zalloc(btrfs_trans_handle_cachep, GFP_NOFS);
524 if (!h) {
525 ret = -ENOMEM;
526 goto alloc_fail;
527 }
528
529
530
531
532
533
534
535
536
537
538
539 if (type & __TRANS_FREEZABLE)
540 sb_start_intwrite(fs_info->sb);
541
542 if (may_wait_transaction(fs_info, type))
543 wait_current_trans(fs_info);
544
545 do {
546 ret = join_transaction(fs_info, type);
547 if (ret == -EBUSY) {
548 wait_current_trans(fs_info);
549 if (unlikely(type == TRANS_ATTACH ||
550 type == TRANS_JOIN_NOSTART))
551 ret = -ENOENT;
552 }
553 } while (ret == -EBUSY);
554
555 if (ret < 0)
556 goto join_fail;
557
558 cur_trans = fs_info->running_transaction;
559
560 h->transid = cur_trans->transid;
561 h->transaction = cur_trans;
562 h->root = root;
563 refcount_set(&h->use_count, 1);
564 h->fs_info = root->fs_info;
565
566 h->type = type;
567 h->can_flush_pending_bgs = true;
568 INIT_LIST_HEAD(&h->new_bgs);
569
570 smp_mb();
571 if (cur_trans->state >= TRANS_STATE_BLOCKED &&
572 may_wait_transaction(fs_info, type)) {
573 current->journal_info = h;
574 btrfs_commit_transaction(h);
575 goto again;
576 }
577
578 if (num_bytes) {
579 trace_btrfs_space_reservation(fs_info, "transaction",
580 h->transid, num_bytes, 1);
581 h->block_rsv = &fs_info->trans_block_rsv;
582 h->bytes_reserved = num_bytes;
583 h->reloc_reserved = reloc_reserved;
584 }
585
586got_it:
587 btrfs_record_root_in_trans(h, root);
588
589 if (!current->journal_info)
590 current->journal_info = h;
591 return h;
592
593join_fail:
594 if (type & __TRANS_FREEZABLE)
595 sb_end_intwrite(fs_info->sb);
596 kmem_cache_free(btrfs_trans_handle_cachep, h);
597alloc_fail:
598 if (num_bytes)
599 btrfs_block_rsv_release(fs_info, &fs_info->trans_block_rsv,
600 num_bytes);
601reserve_fail:
602 btrfs_qgroup_free_meta_pertrans(root, qgroup_reserved);
603 return ERR_PTR(ret);
604}
605
606struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
607 unsigned int num_items)
608{
609 return start_transaction(root, num_items, TRANS_START,
610 BTRFS_RESERVE_FLUSH_ALL, true);
611}
612
613struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
614 struct btrfs_root *root,
615 unsigned int num_items,
616 int min_factor)
617{
618 struct btrfs_fs_info *fs_info = root->fs_info;
619 struct btrfs_trans_handle *trans;
620 u64 num_bytes;
621 int ret;
622
623
624
625
626
627
628
629 trans = start_transaction(root, num_items, TRANS_START,
630 BTRFS_RESERVE_FLUSH_ALL, false);
631 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
632 return trans;
633
634 trans = btrfs_start_transaction(root, 0);
635 if (IS_ERR(trans))
636 return trans;
637
638 num_bytes = btrfs_calc_trans_metadata_size(fs_info, num_items);
639 ret = btrfs_cond_migrate_bytes(fs_info, &fs_info->trans_block_rsv,
640 num_bytes, min_factor);
641 if (ret) {
642 btrfs_end_transaction(trans);
643 return ERR_PTR(ret);
644 }
645
646 trans->block_rsv = &fs_info->trans_block_rsv;
647 trans->bytes_reserved = num_bytes;
648 trace_btrfs_space_reservation(fs_info, "transaction",
649 trans->transid, num_bytes, 1);
650
651 return trans;
652}
653
654struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root)
655{
656 return start_transaction(root, 0, TRANS_JOIN, BTRFS_RESERVE_NO_FLUSH,
657 true);
658}
659
660struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root)
661{
662 return start_transaction(root, 0, TRANS_JOIN_NOLOCK,
663 BTRFS_RESERVE_NO_FLUSH, true);
664}
665
666
667
668
669
670struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root)
671{
672 return start_transaction(root, 0, TRANS_JOIN_NOSTART,
673 BTRFS_RESERVE_NO_FLUSH, true);
674}
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root)
690{
691 return start_transaction(root, 0, TRANS_ATTACH,
692 BTRFS_RESERVE_NO_FLUSH, true);
693}
694
695
696
697
698
699
700
701
702struct btrfs_trans_handle *
703btrfs_attach_transaction_barrier(struct btrfs_root *root)
704{
705 struct btrfs_trans_handle *trans;
706
707 trans = start_transaction(root, 0, TRANS_ATTACH,
708 BTRFS_RESERVE_NO_FLUSH, true);
709 if (trans == ERR_PTR(-ENOENT))
710 btrfs_wait_for_commit(root->fs_info, 0);
711
712 return trans;
713}
714
715
716static noinline void wait_for_commit(struct btrfs_transaction *commit)
717{
718 wait_event(commit->commit_wait, commit->state == TRANS_STATE_COMPLETED);
719}
720
721int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid)
722{
723 struct btrfs_transaction *cur_trans = NULL, *t;
724 int ret = 0;
725
726 if (transid) {
727 if (transid <= fs_info->last_trans_committed)
728 goto out;
729
730
731 spin_lock(&fs_info->trans_lock);
732 list_for_each_entry(t, &fs_info->trans_list, list) {
733 if (t->transid == transid) {
734 cur_trans = t;
735 refcount_inc(&cur_trans->use_count);
736 ret = 0;
737 break;
738 }
739 if (t->transid > transid) {
740 ret = 0;
741 break;
742 }
743 }
744 spin_unlock(&fs_info->trans_lock);
745
746
747
748
749
750 if (!cur_trans) {
751 if (transid > fs_info->last_trans_committed)
752 ret = -EINVAL;
753 goto out;
754 }
755 } else {
756
757 spin_lock(&fs_info->trans_lock);
758 list_for_each_entry_reverse(t, &fs_info->trans_list,
759 list) {
760 if (t->state >= TRANS_STATE_COMMIT_START) {
761 if (t->state == TRANS_STATE_COMPLETED)
762 break;
763 cur_trans = t;
764 refcount_inc(&cur_trans->use_count);
765 break;
766 }
767 }
768 spin_unlock(&fs_info->trans_lock);
769 if (!cur_trans)
770 goto out;
771 }
772
773 wait_for_commit(cur_trans);
774 btrfs_put_transaction(cur_trans);
775out:
776 return ret;
777}
778
779void btrfs_throttle(struct btrfs_fs_info *fs_info)
780{
781 wait_current_trans(fs_info);
782}
783
784static int should_end_transaction(struct btrfs_trans_handle *trans)
785{
786 struct btrfs_fs_info *fs_info = trans->fs_info;
787
788 if (btrfs_check_space_for_delayed_refs(fs_info))
789 return 1;
790
791 return !!btrfs_block_rsv_check(&fs_info->global_block_rsv, 5);
792}
793
794int btrfs_should_end_transaction(struct btrfs_trans_handle *trans)
795{
796 struct btrfs_transaction *cur_trans = trans->transaction;
797
798 smp_mb();
799 if (cur_trans->state >= TRANS_STATE_BLOCKED ||
800 cur_trans->delayed_refs.flushing)
801 return 1;
802
803 return should_end_transaction(trans);
804}
805
806static void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans)
807
808{
809 struct btrfs_fs_info *fs_info = trans->fs_info;
810
811 if (!trans->block_rsv) {
812 ASSERT(!trans->bytes_reserved);
813 return;
814 }
815
816 if (!trans->bytes_reserved)
817 return;
818
819 ASSERT(trans->block_rsv == &fs_info->trans_block_rsv);
820 trace_btrfs_space_reservation(fs_info, "transaction",
821 trans->transid, trans->bytes_reserved, 0);
822 btrfs_block_rsv_release(fs_info, trans->block_rsv,
823 trans->bytes_reserved);
824 trans->bytes_reserved = 0;
825}
826
827static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
828 int throttle)
829{
830 struct btrfs_fs_info *info = trans->fs_info;
831 struct btrfs_transaction *cur_trans = trans->transaction;
832 int lock = (trans->type != TRANS_JOIN_NOLOCK);
833 int err = 0;
834
835 if (refcount_read(&trans->use_count) > 1) {
836 refcount_dec(&trans->use_count);
837 trans->block_rsv = trans->orig_rsv;
838 return 0;
839 }
840
841 btrfs_trans_release_metadata(trans);
842 trans->block_rsv = NULL;
843
844 btrfs_create_pending_block_groups(trans);
845
846 btrfs_trans_release_chunk_metadata(trans);
847
848 if (lock && READ_ONCE(cur_trans->state) == TRANS_STATE_BLOCKED) {
849 if (throttle)
850 return btrfs_commit_transaction(trans);
851 else
852 wake_up_process(info->transaction_kthread);
853 }
854
855 if (trans->type & __TRANS_FREEZABLE)
856 sb_end_intwrite(info->sb);
857
858 WARN_ON(cur_trans != info->running_transaction);
859 WARN_ON(atomic_read(&cur_trans->num_writers) < 1);
860 atomic_dec(&cur_trans->num_writers);
861 extwriter_counter_dec(cur_trans, trans->type);
862
863 cond_wake_up(&cur_trans->writer_wait);
864 btrfs_put_transaction(cur_trans);
865
866 if (current->journal_info == trans)
867 current->journal_info = NULL;
868
869 if (throttle)
870 btrfs_run_delayed_iputs(info);
871
872 if (trans->aborted ||
873 test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) {
874 wake_up_process(info->transaction_kthread);
875 err = -EIO;
876 }
877
878 kmem_cache_free(btrfs_trans_handle_cachep, trans);
879 return err;
880}
881
882int btrfs_end_transaction(struct btrfs_trans_handle *trans)
883{
884 return __btrfs_end_transaction(trans, 0);
885}
886
887int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans)
888{
889 return __btrfs_end_transaction(trans, 1);
890}
891
892
893
894
895
896
897int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
898 struct extent_io_tree *dirty_pages, int mark)
899{
900 int err = 0;
901 int werr = 0;
902 struct address_space *mapping = fs_info->btree_inode->i_mapping;
903 struct extent_state *cached_state = NULL;
904 u64 start = 0;
905 u64 end;
906
907 atomic_inc(&BTRFS_I(fs_info->btree_inode)->sync_writers);
908 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
909 mark, &cached_state)) {
910 bool wait_writeback = false;
911
912 err = convert_extent_bit(dirty_pages, start, end,
913 EXTENT_NEED_WAIT,
914 mark, &cached_state);
915
916
917
918
919
920
921
922
923
924
925
926
927
928 if (err == -ENOMEM) {
929 err = 0;
930 wait_writeback = true;
931 }
932 if (!err)
933 err = filemap_fdatawrite_range(mapping, start, end);
934 if (err)
935 werr = err;
936 else if (wait_writeback)
937 werr = filemap_fdatawait_range(mapping, start, end);
938 free_extent_state(cached_state);
939 cached_state = NULL;
940 cond_resched();
941 start = end + 1;
942 }
943 atomic_dec(&BTRFS_I(fs_info->btree_inode)->sync_writers);
944 return werr;
945}
946
947
948
949
950
951
952
953static int __btrfs_wait_marked_extents(struct btrfs_fs_info *fs_info,
954 struct extent_io_tree *dirty_pages)
955{
956 int err = 0;
957 int werr = 0;
958 struct address_space *mapping = fs_info->btree_inode->i_mapping;
959 struct extent_state *cached_state = NULL;
960 u64 start = 0;
961 u64 end;
962
963 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
964 EXTENT_NEED_WAIT, &cached_state)) {
965
966
967
968
969
970
971
972
973 err = clear_extent_bit(dirty_pages, start, end,
974 EXTENT_NEED_WAIT, 0, 0, &cached_state);
975 if (err == -ENOMEM)
976 err = 0;
977 if (!err)
978 err = filemap_fdatawait_range(mapping, start, end);
979 if (err)
980 werr = err;
981 free_extent_state(cached_state);
982 cached_state = NULL;
983 cond_resched();
984 start = end + 1;
985 }
986 if (err)
987 werr = err;
988 return werr;
989}
990
991int btrfs_wait_extents(struct btrfs_fs_info *fs_info,
992 struct extent_io_tree *dirty_pages)
993{
994 bool errors = false;
995 int err;
996
997 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
998 if (test_and_clear_bit(BTRFS_FS_BTREE_ERR, &fs_info->flags))
999 errors = true;
1000
1001 if (errors && !err)
1002 err = -EIO;
1003 return err;
1004}
1005
1006int btrfs_wait_tree_log_extents(struct btrfs_root *log_root, int mark)
1007{
1008 struct btrfs_fs_info *fs_info = log_root->fs_info;
1009 struct extent_io_tree *dirty_pages = &log_root->dirty_log_pages;
1010 bool errors = false;
1011 int err;
1012
1013 ASSERT(log_root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
1014
1015 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
1016 if ((mark & EXTENT_DIRTY) &&
1017 test_and_clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags))
1018 errors = true;
1019
1020 if ((mark & EXTENT_NEW) &&
1021 test_and_clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags))
1022 errors = true;
1023
1024 if (errors && !err)
1025 err = -EIO;
1026 return err;
1027}
1028
1029
1030
1031
1032
1033
1034
1035
1036static int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans)
1037{
1038 int ret;
1039 int ret2;
1040 struct extent_io_tree *dirty_pages = &trans->transaction->dirty_pages;
1041 struct btrfs_fs_info *fs_info = trans->fs_info;
1042 struct blk_plug plug;
1043
1044 blk_start_plug(&plug);
1045 ret = btrfs_write_marked_extents(fs_info, dirty_pages, EXTENT_DIRTY);
1046 blk_finish_plug(&plug);
1047 ret2 = btrfs_wait_extents(fs_info, dirty_pages);
1048
1049 extent_io_tree_release(&trans->transaction->dirty_pages);
1050
1051 if (ret)
1052 return ret;
1053 else if (ret2)
1054 return ret2;
1055 else
1056 return 0;
1057}
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069static int update_cowonly_root(struct btrfs_trans_handle *trans,
1070 struct btrfs_root *root)
1071{
1072 int ret;
1073 u64 old_root_bytenr;
1074 u64 old_root_used;
1075 struct btrfs_fs_info *fs_info = root->fs_info;
1076 struct btrfs_root *tree_root = fs_info->tree_root;
1077
1078 old_root_used = btrfs_root_used(&root->root_item);
1079
1080 while (1) {
1081 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
1082 if (old_root_bytenr == root->node->start &&
1083 old_root_used == btrfs_root_used(&root->root_item))
1084 break;
1085
1086 btrfs_set_root_node(&root->root_item, root->node);
1087 ret = btrfs_update_root(trans, tree_root,
1088 &root->root_key,
1089 &root->root_item);
1090 if (ret)
1091 return ret;
1092
1093 old_root_used = btrfs_root_used(&root->root_item);
1094 }
1095
1096 return 0;
1097}
1098
1099
1100
1101
1102
1103
1104
1105
1106static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans)
1107{
1108 struct btrfs_fs_info *fs_info = trans->fs_info;
1109 struct list_head *dirty_bgs = &trans->transaction->dirty_bgs;
1110 struct list_head *io_bgs = &trans->transaction->io_bgs;
1111 struct list_head *next;
1112 struct extent_buffer *eb;
1113 int ret;
1114
1115 eb = btrfs_lock_root_node(fs_info->tree_root);
1116 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL,
1117 0, &eb);
1118 btrfs_tree_unlock(eb);
1119 free_extent_buffer(eb);
1120
1121 if (ret)
1122 return ret;
1123
1124 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1125 if (ret)
1126 return ret;
1127
1128 ret = btrfs_run_dev_stats(trans);
1129 if (ret)
1130 return ret;
1131 ret = btrfs_run_dev_replace(trans);
1132 if (ret)
1133 return ret;
1134 ret = btrfs_run_qgroups(trans);
1135 if (ret)
1136 return ret;
1137
1138 ret = btrfs_setup_space_cache(trans);
1139 if (ret)
1140 return ret;
1141
1142
1143 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1144 if (ret)
1145 return ret;
1146again:
1147 while (!list_empty(&fs_info->dirty_cowonly_roots)) {
1148 struct btrfs_root *root;
1149 next = fs_info->dirty_cowonly_roots.next;
1150 list_del_init(next);
1151 root = list_entry(next, struct btrfs_root, dirty_list);
1152 clear_bit(BTRFS_ROOT_DIRTY, &root->state);
1153
1154 if (root != fs_info->extent_root)
1155 list_add_tail(&root->dirty_list,
1156 &trans->transaction->switch_commits);
1157 ret = update_cowonly_root(trans, root);
1158 if (ret)
1159 return ret;
1160 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1161 if (ret)
1162 return ret;
1163 }
1164
1165 while (!list_empty(dirty_bgs) || !list_empty(io_bgs)) {
1166 ret = btrfs_write_dirty_block_groups(trans);
1167 if (ret)
1168 return ret;
1169 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1170 if (ret)
1171 return ret;
1172 }
1173
1174 if (!list_empty(&fs_info->dirty_cowonly_roots))
1175 goto again;
1176
1177 list_add_tail(&fs_info->extent_root->dirty_list,
1178 &trans->transaction->switch_commits);
1179
1180
1181 fs_info->dev_replace.committed_cursor_left =
1182 fs_info->dev_replace.cursor_left_last_write_of_item;
1183
1184 return 0;
1185}
1186
1187
1188
1189
1190
1191
1192void btrfs_add_dead_root(struct btrfs_root *root)
1193{
1194 struct btrfs_fs_info *fs_info = root->fs_info;
1195
1196 spin_lock(&fs_info->trans_lock);
1197 if (list_empty(&root->root_list))
1198 list_add_tail(&root->root_list, &fs_info->dead_roots);
1199 spin_unlock(&fs_info->trans_lock);
1200}
1201
1202
1203
1204
1205static noinline int commit_fs_roots(struct btrfs_trans_handle *trans)
1206{
1207 struct btrfs_fs_info *fs_info = trans->fs_info;
1208 struct btrfs_root *gang[8];
1209 int i;
1210 int ret;
1211 int err = 0;
1212
1213 spin_lock(&fs_info->fs_roots_radix_lock);
1214 while (1) {
1215 ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
1216 (void **)gang, 0,
1217 ARRAY_SIZE(gang),
1218 BTRFS_ROOT_TRANS_TAG);
1219 if (ret == 0)
1220 break;
1221 for (i = 0; i < ret; i++) {
1222 struct btrfs_root *root = gang[i];
1223 radix_tree_tag_clear(&fs_info->fs_roots_radix,
1224 (unsigned long)root->root_key.objectid,
1225 BTRFS_ROOT_TRANS_TAG);
1226 spin_unlock(&fs_info->fs_roots_radix_lock);
1227
1228 btrfs_free_log(trans, root);
1229 btrfs_update_reloc_root(trans, root);
1230
1231 btrfs_save_ino_cache(root, trans);
1232
1233
1234 clear_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1235 smp_mb__after_atomic();
1236
1237 if (root->commit_root != root->node) {
1238 list_add_tail(&root->dirty_list,
1239 &trans->transaction->switch_commits);
1240 btrfs_set_root_node(&root->root_item,
1241 root->node);
1242 }
1243
1244 err = btrfs_update_root(trans, fs_info->tree_root,
1245 &root->root_key,
1246 &root->root_item);
1247 spin_lock(&fs_info->fs_roots_radix_lock);
1248 if (err)
1249 break;
1250 btrfs_qgroup_free_meta_all_pertrans(root);
1251 }
1252 }
1253 spin_unlock(&fs_info->fs_roots_radix_lock);
1254 return err;
1255}
1256
1257
1258
1259
1260
1261int btrfs_defrag_root(struct btrfs_root *root)
1262{
1263 struct btrfs_fs_info *info = root->fs_info;
1264 struct btrfs_trans_handle *trans;
1265 int ret;
1266
1267 if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state))
1268 return 0;
1269
1270 while (1) {
1271 trans = btrfs_start_transaction(root, 0);
1272 if (IS_ERR(trans))
1273 return PTR_ERR(trans);
1274
1275 ret = btrfs_defrag_leaves(trans, root);
1276
1277 btrfs_end_transaction(trans);
1278 btrfs_btree_balance_dirty(info);
1279 cond_resched();
1280
1281 if (btrfs_fs_closing(info) || ret != -EAGAIN)
1282 break;
1283
1284 if (btrfs_defrag_cancelled(info)) {
1285 btrfs_debug(info, "defrag_root cancelled");
1286 ret = -EAGAIN;
1287 break;
1288 }
1289 }
1290 clear_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state);
1291 return ret;
1292}
1293
1294
1295
1296
1297
1298
1299
1300
1301static int qgroup_account_snapshot(struct btrfs_trans_handle *trans,
1302 struct btrfs_root *src,
1303 struct btrfs_root *parent,
1304 struct btrfs_qgroup_inherit *inherit,
1305 u64 dst_objectid)
1306{
1307 struct btrfs_fs_info *fs_info = src->fs_info;
1308 int ret;
1309
1310
1311
1312
1313
1314
1315 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1316 return 0;
1317
1318
1319
1320
1321
1322
1323
1324 record_root_in_trans(trans, src, 1);
1325
1326
1327
1328
1329
1330 mutex_lock(&fs_info->tree_log_mutex);
1331
1332 ret = commit_fs_roots(trans);
1333 if (ret)
1334 goto out;
1335 ret = btrfs_qgroup_account_extents(trans);
1336 if (ret < 0)
1337 goto out;
1338
1339
1340 ret = btrfs_qgroup_inherit(trans, src->root_key.objectid, dst_objectid,
1341 inherit);
1342 if (ret < 0)
1343 goto out;
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357 ret = commit_cowonly_roots(trans);
1358 if (ret)
1359 goto out;
1360 switch_commit_roots(trans->transaction);
1361 ret = btrfs_write_and_wait_transaction(trans);
1362 if (ret)
1363 btrfs_handle_fs_error(fs_info, ret,
1364 "Error while writing out transaction for qgroup");
1365
1366out:
1367 mutex_unlock(&fs_info->tree_log_mutex);
1368
1369
1370
1371
1372
1373
1374
1375 if (!ret)
1376 record_root_in_trans(trans, parent, 1);
1377 return ret;
1378}
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
1390 struct btrfs_pending_snapshot *pending)
1391{
1392
1393 struct btrfs_fs_info *fs_info = trans->fs_info;
1394 struct btrfs_key key;
1395 struct btrfs_root_item *new_root_item;
1396 struct btrfs_root *tree_root = fs_info->tree_root;
1397 struct btrfs_root *root = pending->root;
1398 struct btrfs_root *parent_root;
1399 struct btrfs_block_rsv *rsv;
1400 struct inode *parent_inode;
1401 struct btrfs_path *path;
1402 struct btrfs_dir_item *dir_item;
1403 struct dentry *dentry;
1404 struct extent_buffer *tmp;
1405 struct extent_buffer *old;
1406 struct timespec64 cur_time;
1407 int ret = 0;
1408 u64 to_reserve = 0;
1409 u64 index = 0;
1410 u64 objectid;
1411 u64 root_flags;
1412 uuid_le new_uuid;
1413
1414 ASSERT(pending->path);
1415 path = pending->path;
1416
1417 ASSERT(pending->root_item);
1418 new_root_item = pending->root_item;
1419
1420 pending->error = btrfs_find_free_objectid(tree_root, &objectid);
1421 if (pending->error)
1422 goto no_free_objectid;
1423
1424
1425
1426
1427
1428 btrfs_set_skip_qgroup(trans, objectid);
1429
1430 btrfs_reloc_pre_snapshot(pending, &to_reserve);
1431
1432 if (to_reserve > 0) {
1433 pending->error = btrfs_block_rsv_add(root,
1434 &pending->block_rsv,
1435 to_reserve,
1436 BTRFS_RESERVE_NO_FLUSH);
1437 if (pending->error)
1438 goto clear_skip_qgroup;
1439 }
1440
1441 key.objectid = objectid;
1442 key.offset = (u64)-1;
1443 key.type = BTRFS_ROOT_ITEM_KEY;
1444
1445 rsv = trans->block_rsv;
1446 trans->block_rsv = &pending->block_rsv;
1447 trans->bytes_reserved = trans->block_rsv->reserved;
1448 trace_btrfs_space_reservation(fs_info, "transaction",
1449 trans->transid,
1450 trans->bytes_reserved, 1);
1451 dentry = pending->dentry;
1452 parent_inode = pending->dir;
1453 parent_root = BTRFS_I(parent_inode)->root;
1454 record_root_in_trans(trans, parent_root, 0);
1455
1456 cur_time = current_time(parent_inode);
1457
1458
1459
1460
1461 ret = btrfs_set_inode_index(BTRFS_I(parent_inode), &index);
1462 BUG_ON(ret);
1463
1464
1465 dir_item = btrfs_lookup_dir_item(NULL, parent_root, path,
1466 btrfs_ino(BTRFS_I(parent_inode)),
1467 dentry->d_name.name,
1468 dentry->d_name.len, 0);
1469 if (dir_item != NULL && !IS_ERR(dir_item)) {
1470 pending->error = -EEXIST;
1471 goto dir_item_existed;
1472 } else if (IS_ERR(dir_item)) {
1473 ret = PTR_ERR(dir_item);
1474 btrfs_abort_transaction(trans, ret);
1475 goto fail;
1476 }
1477 btrfs_release_path(path);
1478
1479
1480
1481
1482
1483
1484
1485 ret = btrfs_run_delayed_items(trans);
1486 if (ret) {
1487 btrfs_abort_transaction(trans, ret);
1488 goto fail;
1489 }
1490
1491 record_root_in_trans(trans, root, 0);
1492 btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
1493 memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
1494 btrfs_check_and_init_root_item(new_root_item);
1495
1496 root_flags = btrfs_root_flags(new_root_item);
1497 if (pending->readonly)
1498 root_flags |= BTRFS_ROOT_SUBVOL_RDONLY;
1499 else
1500 root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY;
1501 btrfs_set_root_flags(new_root_item, root_flags);
1502
1503 btrfs_set_root_generation_v2(new_root_item,
1504 trans->transid);
1505 uuid_le_gen(&new_uuid);
1506 memcpy(new_root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
1507 memcpy(new_root_item->parent_uuid, root->root_item.uuid,
1508 BTRFS_UUID_SIZE);
1509 if (!(root_flags & BTRFS_ROOT_SUBVOL_RDONLY)) {
1510 memset(new_root_item->received_uuid, 0,
1511 sizeof(new_root_item->received_uuid));
1512 memset(&new_root_item->stime, 0, sizeof(new_root_item->stime));
1513 memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime));
1514 btrfs_set_root_stransid(new_root_item, 0);
1515 btrfs_set_root_rtransid(new_root_item, 0);
1516 }
1517 btrfs_set_stack_timespec_sec(&new_root_item->otime, cur_time.tv_sec);
1518 btrfs_set_stack_timespec_nsec(&new_root_item->otime, cur_time.tv_nsec);
1519 btrfs_set_root_otransid(new_root_item, trans->transid);
1520
1521 old = btrfs_lock_root_node(root);
1522 ret = btrfs_cow_block(trans, root, old, NULL, 0, &old);
1523 if (ret) {
1524 btrfs_tree_unlock(old);
1525 free_extent_buffer(old);
1526 btrfs_abort_transaction(trans, ret);
1527 goto fail;
1528 }
1529
1530 btrfs_set_lock_blocking_write(old);
1531
1532 ret = btrfs_copy_root(trans, root, old, &tmp, objectid);
1533
1534 btrfs_tree_unlock(old);
1535 free_extent_buffer(old);
1536 if (ret) {
1537 btrfs_abort_transaction(trans, ret);
1538 goto fail;
1539 }
1540
1541 set_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1542 smp_wmb();
1543
1544 btrfs_set_root_node(new_root_item, tmp);
1545
1546 key.offset = trans->transid;
1547 ret = btrfs_insert_root(trans, tree_root, &key, new_root_item);
1548 btrfs_tree_unlock(tmp);
1549 free_extent_buffer(tmp);
1550 if (ret) {
1551 btrfs_abort_transaction(trans, ret);
1552 goto fail;
1553 }
1554
1555
1556
1557
1558 ret = btrfs_add_root_ref(trans, objectid,
1559 parent_root->root_key.objectid,
1560 btrfs_ino(BTRFS_I(parent_inode)), index,
1561 dentry->d_name.name, dentry->d_name.len);
1562 if (ret) {
1563 btrfs_abort_transaction(trans, ret);
1564 goto fail;
1565 }
1566
1567 key.offset = (u64)-1;
1568 pending->snap = btrfs_read_fs_root_no_name(fs_info, &key);
1569 if (IS_ERR(pending->snap)) {
1570 ret = PTR_ERR(pending->snap);
1571 btrfs_abort_transaction(trans, ret);
1572 goto fail;
1573 }
1574
1575 ret = btrfs_reloc_post_snapshot(trans, pending);
1576 if (ret) {
1577 btrfs_abort_transaction(trans, ret);
1578 goto fail;
1579 }
1580
1581 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1582 if (ret) {
1583 btrfs_abort_transaction(trans, ret);
1584 goto fail;
1585 }
1586
1587
1588
1589
1590
1591
1592
1593 ret = qgroup_account_snapshot(trans, root, parent_root,
1594 pending->inherit, objectid);
1595 if (ret < 0)
1596 goto fail;
1597
1598 ret = btrfs_insert_dir_item(trans, dentry->d_name.name,
1599 dentry->d_name.len, BTRFS_I(parent_inode),
1600 &key, BTRFS_FT_DIR, index);
1601
1602 BUG_ON(ret == -EEXIST || ret == -EOVERFLOW);
1603 if (ret) {
1604 btrfs_abort_transaction(trans, ret);
1605 goto fail;
1606 }
1607
1608 btrfs_i_size_write(BTRFS_I(parent_inode), parent_inode->i_size +
1609 dentry->d_name.len * 2);
1610 parent_inode->i_mtime = parent_inode->i_ctime =
1611 current_time(parent_inode);
1612 ret = btrfs_update_inode_fallback(trans, parent_root, parent_inode);
1613 if (ret) {
1614 btrfs_abort_transaction(trans, ret);
1615 goto fail;
1616 }
1617 ret = btrfs_uuid_tree_add(trans, new_uuid.b, BTRFS_UUID_KEY_SUBVOL,
1618 objectid);
1619 if (ret) {
1620 btrfs_abort_transaction(trans, ret);
1621 goto fail;
1622 }
1623 if (!btrfs_is_empty_uuid(new_root_item->received_uuid)) {
1624 ret = btrfs_uuid_tree_add(trans, new_root_item->received_uuid,
1625 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
1626 objectid);
1627 if (ret && ret != -EEXIST) {
1628 btrfs_abort_transaction(trans, ret);
1629 goto fail;
1630 }
1631 }
1632
1633 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1634 if (ret) {
1635 btrfs_abort_transaction(trans, ret);
1636 goto fail;
1637 }
1638
1639fail:
1640 pending->error = ret;
1641dir_item_existed:
1642 trans->block_rsv = rsv;
1643 trans->bytes_reserved = 0;
1644clear_skip_qgroup:
1645 btrfs_clear_skip_qgroup(trans);
1646no_free_objectid:
1647 kfree(new_root_item);
1648 pending->root_item = NULL;
1649 btrfs_free_path(path);
1650 pending->path = NULL;
1651
1652 return ret;
1653}
1654
1655
1656
1657
1658static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans)
1659{
1660 struct btrfs_pending_snapshot *pending, *next;
1661 struct list_head *head = &trans->transaction->pending_snapshots;
1662 int ret = 0;
1663
1664 list_for_each_entry_safe(pending, next, head, list) {
1665 list_del(&pending->list);
1666 ret = create_pending_snapshot(trans, pending);
1667 if (ret)
1668 break;
1669 }
1670 return ret;
1671}
1672
1673static void update_super_roots(struct btrfs_fs_info *fs_info)
1674{
1675 struct btrfs_root_item *root_item;
1676 struct btrfs_super_block *super;
1677
1678 super = fs_info->super_copy;
1679
1680 root_item = &fs_info->chunk_root->root_item;
1681 super->chunk_root = root_item->bytenr;
1682 super->chunk_root_generation = root_item->generation;
1683 super->chunk_root_level = root_item->level;
1684
1685 root_item = &fs_info->tree_root->root_item;
1686 super->root = root_item->bytenr;
1687 super->generation = root_item->generation;
1688 super->root_level = root_item->level;
1689 if (btrfs_test_opt(fs_info, SPACE_CACHE))
1690 super->cache_generation = root_item->generation;
1691 if (test_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags))
1692 super->uuid_tree_generation = root_item->generation;
1693}
1694
1695int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
1696{
1697 struct btrfs_transaction *trans;
1698 int ret = 0;
1699
1700 spin_lock(&info->trans_lock);
1701 trans = info->running_transaction;
1702 if (trans)
1703 ret = (trans->state >= TRANS_STATE_COMMIT_START);
1704 spin_unlock(&info->trans_lock);
1705 return ret;
1706}
1707
1708int btrfs_transaction_blocked(struct btrfs_fs_info *info)
1709{
1710 struct btrfs_transaction *trans;
1711 int ret = 0;
1712
1713 spin_lock(&info->trans_lock);
1714 trans = info->running_transaction;
1715 if (trans)
1716 ret = is_transaction_blocked(trans);
1717 spin_unlock(&info->trans_lock);
1718 return ret;
1719}
1720
1721
1722
1723
1724
1725static void wait_current_trans_commit_start(struct btrfs_fs_info *fs_info,
1726 struct btrfs_transaction *trans)
1727{
1728 wait_event(fs_info->transaction_blocked_wait,
1729 trans->state >= TRANS_STATE_COMMIT_START || trans->aborted);
1730}
1731
1732
1733
1734
1735
1736static void wait_current_trans_commit_start_and_unblock(
1737 struct btrfs_fs_info *fs_info,
1738 struct btrfs_transaction *trans)
1739{
1740 wait_event(fs_info->transaction_wait,
1741 trans->state >= TRANS_STATE_UNBLOCKED || trans->aborted);
1742}
1743
1744
1745
1746
1747
1748struct btrfs_async_commit {
1749 struct btrfs_trans_handle *newtrans;
1750 struct work_struct work;
1751};
1752
1753static void do_async_commit(struct work_struct *work)
1754{
1755 struct btrfs_async_commit *ac =
1756 container_of(work, struct btrfs_async_commit, work);
1757
1758
1759
1760
1761
1762 if (ac->newtrans->type & __TRANS_FREEZABLE)
1763 __sb_writers_acquired(ac->newtrans->fs_info->sb, SB_FREEZE_FS);
1764
1765 current->journal_info = ac->newtrans;
1766
1767 btrfs_commit_transaction(ac->newtrans);
1768 kfree(ac);
1769}
1770
1771int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
1772 int wait_for_unblock)
1773{
1774 struct btrfs_fs_info *fs_info = trans->fs_info;
1775 struct btrfs_async_commit *ac;
1776 struct btrfs_transaction *cur_trans;
1777
1778 ac = kmalloc(sizeof(*ac), GFP_NOFS);
1779 if (!ac)
1780 return -ENOMEM;
1781
1782 INIT_WORK(&ac->work, do_async_commit);
1783 ac->newtrans = btrfs_join_transaction(trans->root);
1784 if (IS_ERR(ac->newtrans)) {
1785 int err = PTR_ERR(ac->newtrans);
1786 kfree(ac);
1787 return err;
1788 }
1789
1790
1791 cur_trans = trans->transaction;
1792 refcount_inc(&cur_trans->use_count);
1793
1794 btrfs_end_transaction(trans);
1795
1796
1797
1798
1799
1800 if (ac->newtrans->type & __TRANS_FREEZABLE)
1801 __sb_writers_release(fs_info->sb, SB_FREEZE_FS);
1802
1803 schedule_work(&ac->work);
1804
1805
1806 if (wait_for_unblock)
1807 wait_current_trans_commit_start_and_unblock(fs_info, cur_trans);
1808 else
1809 wait_current_trans_commit_start(fs_info, cur_trans);
1810
1811 if (current->journal_info == trans)
1812 current->journal_info = NULL;
1813
1814 btrfs_put_transaction(cur_trans);
1815 return 0;
1816}
1817
1818
1819static void cleanup_transaction(struct btrfs_trans_handle *trans, int err)
1820{
1821 struct btrfs_fs_info *fs_info = trans->fs_info;
1822 struct btrfs_transaction *cur_trans = trans->transaction;
1823
1824 WARN_ON(refcount_read(&trans->use_count) > 1);
1825
1826 btrfs_abort_transaction(trans, err);
1827
1828 spin_lock(&fs_info->trans_lock);
1829
1830
1831
1832
1833
1834
1835 BUG_ON(list_empty(&cur_trans->list));
1836
1837 list_del_init(&cur_trans->list);
1838 if (cur_trans == fs_info->running_transaction) {
1839 cur_trans->state = TRANS_STATE_COMMIT_DOING;
1840 spin_unlock(&fs_info->trans_lock);
1841 wait_event(cur_trans->writer_wait,
1842 atomic_read(&cur_trans->num_writers) == 1);
1843
1844 spin_lock(&fs_info->trans_lock);
1845 }
1846 spin_unlock(&fs_info->trans_lock);
1847
1848 btrfs_cleanup_one_transaction(trans->transaction, fs_info);
1849
1850 spin_lock(&fs_info->trans_lock);
1851 if (cur_trans == fs_info->running_transaction)
1852 fs_info->running_transaction = NULL;
1853 spin_unlock(&fs_info->trans_lock);
1854
1855 if (trans->type & __TRANS_FREEZABLE)
1856 sb_end_intwrite(fs_info->sb);
1857 btrfs_put_transaction(cur_trans);
1858 btrfs_put_transaction(cur_trans);
1859
1860 trace_btrfs_transaction_commit(trans->root);
1861
1862 if (current->journal_info == trans)
1863 current->journal_info = NULL;
1864 btrfs_scrub_cancel(fs_info);
1865
1866 kmem_cache_free(btrfs_trans_handle_cachep, trans);
1867}
1868
1869
1870
1871
1872
1873static void btrfs_cleanup_pending_block_groups(struct btrfs_trans_handle *trans)
1874{
1875 struct btrfs_fs_info *fs_info = trans->fs_info;
1876 struct btrfs_block_group_cache *block_group, *tmp;
1877
1878 list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
1879 btrfs_delayed_refs_rsv_release(fs_info, 1);
1880 list_del_init(&block_group->bg_list);
1881 }
1882}
1883
1884static inline int btrfs_start_delalloc_flush(struct btrfs_trans_handle *trans)
1885{
1886 struct btrfs_fs_info *fs_info = trans->fs_info;
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) {
1898 writeback_inodes_sb(fs_info->sb, WB_REASON_SYNC);
1899 } else {
1900 struct btrfs_pending_snapshot *pending;
1901 struct list_head *head = &trans->transaction->pending_snapshots;
1902
1903
1904
1905
1906
1907
1908
1909
1910 list_for_each_entry(pending, head, list) {
1911 int ret;
1912
1913 ret = btrfs_start_delalloc_snapshot(pending->root);
1914 if (ret)
1915 return ret;
1916 }
1917 }
1918 return 0;
1919}
1920
1921static inline void btrfs_wait_delalloc_flush(struct btrfs_trans_handle *trans)
1922{
1923 struct btrfs_fs_info *fs_info = trans->fs_info;
1924
1925 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) {
1926 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
1927 } else {
1928 struct btrfs_pending_snapshot *pending;
1929 struct list_head *head = &trans->transaction->pending_snapshots;
1930
1931
1932
1933
1934
1935
1936
1937 list_for_each_entry(pending, head, list)
1938 btrfs_wait_ordered_extents(pending->root,
1939 U64_MAX, 0, U64_MAX);
1940 }
1941}
1942
1943int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
1944{
1945 struct btrfs_fs_info *fs_info = trans->fs_info;
1946 struct btrfs_transaction *cur_trans = trans->transaction;
1947 struct btrfs_transaction *prev_trans = NULL;
1948 int ret;
1949
1950
1951 if (unlikely(READ_ONCE(cur_trans->aborted))) {
1952 ret = cur_trans->aborted;
1953 btrfs_end_transaction(trans);
1954 return ret;
1955 }
1956
1957 btrfs_trans_release_metadata(trans);
1958 trans->block_rsv = NULL;
1959
1960
1961
1962
1963 ret = btrfs_run_delayed_refs(trans, 0);
1964 if (ret) {
1965 btrfs_end_transaction(trans);
1966 return ret;
1967 }
1968
1969 cur_trans = trans->transaction;
1970
1971
1972
1973
1974
1975 cur_trans->delayed_refs.flushing = 1;
1976 smp_wmb();
1977
1978 btrfs_create_pending_block_groups(trans);
1979
1980 ret = btrfs_run_delayed_refs(trans, 0);
1981 if (ret) {
1982 btrfs_end_transaction(trans);
1983 return ret;
1984 }
1985
1986 if (!test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &cur_trans->flags)) {
1987 int run_it = 0;
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002 mutex_lock(&fs_info->ro_block_group_mutex);
2003 if (!test_and_set_bit(BTRFS_TRANS_DIRTY_BG_RUN,
2004 &cur_trans->flags))
2005 run_it = 1;
2006 mutex_unlock(&fs_info->ro_block_group_mutex);
2007
2008 if (run_it) {
2009 ret = btrfs_start_dirty_block_groups(trans);
2010 if (ret) {
2011 btrfs_end_transaction(trans);
2012 return ret;
2013 }
2014 }
2015 }
2016
2017 spin_lock(&fs_info->trans_lock);
2018 if (cur_trans->state >= TRANS_STATE_COMMIT_START) {
2019 spin_unlock(&fs_info->trans_lock);
2020 refcount_inc(&cur_trans->use_count);
2021 ret = btrfs_end_transaction(trans);
2022
2023 wait_for_commit(cur_trans);
2024
2025 if (unlikely(cur_trans->aborted))
2026 ret = cur_trans->aborted;
2027
2028 btrfs_put_transaction(cur_trans);
2029
2030 return ret;
2031 }
2032
2033 cur_trans->state = TRANS_STATE_COMMIT_START;
2034 wake_up(&fs_info->transaction_blocked_wait);
2035
2036 if (cur_trans->list.prev != &fs_info->trans_list) {
2037 prev_trans = list_entry(cur_trans->list.prev,
2038 struct btrfs_transaction, list);
2039 if (prev_trans->state != TRANS_STATE_COMPLETED) {
2040 refcount_inc(&prev_trans->use_count);
2041 spin_unlock(&fs_info->trans_lock);
2042
2043 wait_for_commit(prev_trans);
2044 ret = prev_trans->aborted;
2045
2046 btrfs_put_transaction(prev_trans);
2047 if (ret)
2048 goto cleanup_transaction;
2049 } else {
2050 spin_unlock(&fs_info->trans_lock);
2051 }
2052 } else {
2053 spin_unlock(&fs_info->trans_lock);
2054
2055
2056
2057
2058
2059
2060 if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state)) {
2061 ret = -EROFS;
2062 goto cleanup_transaction;
2063 }
2064 }
2065
2066 extwriter_counter_dec(cur_trans, trans->type);
2067
2068 ret = btrfs_start_delalloc_flush(trans);
2069 if (ret)
2070 goto cleanup_transaction;
2071
2072 ret = btrfs_run_delayed_items(trans);
2073 if (ret)
2074 goto cleanup_transaction;
2075
2076 wait_event(cur_trans->writer_wait,
2077 extwriter_counter_read(cur_trans) == 0);
2078
2079
2080 ret = btrfs_run_delayed_items(trans);
2081 if (ret)
2082 goto cleanup_transaction;
2083
2084 btrfs_wait_delalloc_flush(trans);
2085
2086 btrfs_scrub_pause(fs_info);
2087
2088
2089
2090
2091
2092 spin_lock(&fs_info->trans_lock);
2093 cur_trans->state = TRANS_STATE_COMMIT_DOING;
2094 spin_unlock(&fs_info->trans_lock);
2095 wait_event(cur_trans->writer_wait,
2096 atomic_read(&cur_trans->num_writers) == 1);
2097
2098
2099 if (unlikely(READ_ONCE(cur_trans->aborted))) {
2100 ret = cur_trans->aborted;
2101 goto scrub_continue;
2102 }
2103
2104
2105
2106
2107
2108 mutex_lock(&fs_info->reloc_mutex);
2109
2110
2111
2112
2113
2114
2115 ret = create_pending_snapshots(trans);
2116 if (ret) {
2117 mutex_unlock(&fs_info->reloc_mutex);
2118 goto scrub_continue;
2119 }
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131 ret = btrfs_run_delayed_items(trans);
2132 if (ret) {
2133 mutex_unlock(&fs_info->reloc_mutex);
2134 goto scrub_continue;
2135 }
2136
2137 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
2138 if (ret) {
2139 mutex_unlock(&fs_info->reloc_mutex);
2140 goto scrub_continue;
2141 }
2142
2143
2144
2145
2146
2147 btrfs_assert_delayed_root_empty(fs_info);
2148
2149 WARN_ON(cur_trans != trans->transaction);
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164 mutex_lock(&fs_info->tree_log_mutex);
2165
2166 ret = commit_fs_roots(trans);
2167 if (ret) {
2168 mutex_unlock(&fs_info->tree_log_mutex);
2169 mutex_unlock(&fs_info->reloc_mutex);
2170 goto scrub_continue;
2171 }
2172
2173
2174
2175
2176
2177 btrfs_apply_pending_changes(fs_info);
2178
2179
2180
2181
2182 btrfs_free_log_root_tree(trans, fs_info);
2183
2184
2185
2186
2187
2188 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
2189 if (ret) {
2190 mutex_unlock(&fs_info->tree_log_mutex);
2191 mutex_unlock(&fs_info->reloc_mutex);
2192 goto scrub_continue;
2193 }
2194
2195
2196
2197
2198
2199 ret = btrfs_qgroup_account_extents(trans);
2200 if (ret < 0) {
2201 mutex_unlock(&fs_info->tree_log_mutex);
2202 mutex_unlock(&fs_info->reloc_mutex);
2203 goto scrub_continue;
2204 }
2205
2206 ret = commit_cowonly_roots(trans);
2207 if (ret) {
2208 mutex_unlock(&fs_info->tree_log_mutex);
2209 mutex_unlock(&fs_info->reloc_mutex);
2210 goto scrub_continue;
2211 }
2212
2213
2214
2215
2216
2217 if (unlikely(READ_ONCE(cur_trans->aborted))) {
2218 ret = cur_trans->aborted;
2219 mutex_unlock(&fs_info->tree_log_mutex);
2220 mutex_unlock(&fs_info->reloc_mutex);
2221 goto scrub_continue;
2222 }
2223
2224 btrfs_prepare_extent_commit(fs_info);
2225
2226 cur_trans = fs_info->running_transaction;
2227
2228 btrfs_set_root_node(&fs_info->tree_root->root_item,
2229 fs_info->tree_root->node);
2230 list_add_tail(&fs_info->tree_root->dirty_list,
2231 &cur_trans->switch_commits);
2232
2233 btrfs_set_root_node(&fs_info->chunk_root->root_item,
2234 fs_info->chunk_root->node);
2235 list_add_tail(&fs_info->chunk_root->dirty_list,
2236 &cur_trans->switch_commits);
2237
2238 switch_commit_roots(cur_trans);
2239
2240 ASSERT(list_empty(&cur_trans->dirty_bgs));
2241 ASSERT(list_empty(&cur_trans->io_bgs));
2242 update_super_roots(fs_info);
2243
2244 btrfs_set_super_log_root(fs_info->super_copy, 0);
2245 btrfs_set_super_log_root_level(fs_info->super_copy, 0);
2246 memcpy(fs_info->super_for_commit, fs_info->super_copy,
2247 sizeof(*fs_info->super_copy));
2248
2249 btrfs_commit_device_sizes(cur_trans);
2250
2251 clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags);
2252 clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags);
2253
2254 btrfs_trans_release_chunk_metadata(trans);
2255
2256 spin_lock(&fs_info->trans_lock);
2257 cur_trans->state = TRANS_STATE_UNBLOCKED;
2258 fs_info->running_transaction = NULL;
2259 spin_unlock(&fs_info->trans_lock);
2260 mutex_unlock(&fs_info->reloc_mutex);
2261
2262 wake_up(&fs_info->transaction_wait);
2263
2264 ret = btrfs_write_and_wait_transaction(trans);
2265 if (ret) {
2266 btrfs_handle_fs_error(fs_info, ret,
2267 "Error while writing out transaction");
2268 mutex_unlock(&fs_info->tree_log_mutex);
2269 goto scrub_continue;
2270 }
2271
2272 ret = write_all_supers(fs_info, 0);
2273
2274
2275
2276
2277 mutex_unlock(&fs_info->tree_log_mutex);
2278 if (ret)
2279 goto scrub_continue;
2280
2281 btrfs_finish_extent_commit(trans);
2282
2283 if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &cur_trans->flags))
2284 btrfs_clear_space_info_full(fs_info);
2285
2286 fs_info->last_trans_committed = cur_trans->transid;
2287
2288
2289
2290
2291 cur_trans->state = TRANS_STATE_COMPLETED;
2292 wake_up(&cur_trans->commit_wait);
2293 clear_bit(BTRFS_FS_NEED_ASYNC_COMMIT, &fs_info->flags);
2294
2295 spin_lock(&fs_info->trans_lock);
2296 list_del_init(&cur_trans->list);
2297 spin_unlock(&fs_info->trans_lock);
2298
2299 btrfs_put_transaction(cur_trans);
2300 btrfs_put_transaction(cur_trans);
2301
2302 if (trans->type & __TRANS_FREEZABLE)
2303 sb_end_intwrite(fs_info->sb);
2304
2305 trace_btrfs_transaction_commit(trans->root);
2306
2307 btrfs_scrub_continue(fs_info);
2308
2309 if (current->journal_info == trans)
2310 current->journal_info = NULL;
2311
2312 kmem_cache_free(btrfs_trans_handle_cachep, trans);
2313
2314 return ret;
2315
2316scrub_continue:
2317 btrfs_scrub_continue(fs_info);
2318cleanup_transaction:
2319 btrfs_trans_release_metadata(trans);
2320 btrfs_cleanup_pending_block_groups(trans);
2321 btrfs_trans_release_chunk_metadata(trans);
2322 trans->block_rsv = NULL;
2323 btrfs_warn(fs_info, "Skipping commit of aborted transaction.");
2324 if (current->journal_info == trans)
2325 current->journal_info = NULL;
2326 cleanup_transaction(trans, ret);
2327
2328 return ret;
2329}
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root)
2342{
2343 int ret;
2344 struct btrfs_fs_info *fs_info = root->fs_info;
2345
2346 spin_lock(&fs_info->trans_lock);
2347 if (list_empty(&fs_info->dead_roots)) {
2348 spin_unlock(&fs_info->trans_lock);
2349 return 0;
2350 }
2351 root = list_first_entry(&fs_info->dead_roots,
2352 struct btrfs_root, root_list);
2353 list_del_init(&root->root_list);
2354 spin_unlock(&fs_info->trans_lock);
2355
2356 btrfs_debug(fs_info, "cleaner removing %llu", root->root_key.objectid);
2357
2358 btrfs_kill_all_delayed_nodes(root);
2359
2360 if (btrfs_header_backref_rev(root->node) <
2361 BTRFS_MIXED_BACKREF_REV)
2362 ret = btrfs_drop_snapshot(root, NULL, 0, 0);
2363 else
2364 ret = btrfs_drop_snapshot(root, NULL, 1, 0);
2365
2366 return (ret < 0) ? 0 : 1;
2367}
2368
2369void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info)
2370{
2371 unsigned long prev;
2372 unsigned long bit;
2373
2374 prev = xchg(&fs_info->pending_changes, 0);
2375 if (!prev)
2376 return;
2377
2378 bit = 1 << BTRFS_PENDING_SET_INODE_MAP_CACHE;
2379 if (prev & bit)
2380 btrfs_set_opt(fs_info->mount_opt, INODE_MAP_CACHE);
2381 prev &= ~bit;
2382
2383 bit = 1 << BTRFS_PENDING_CLEAR_INODE_MAP_CACHE;
2384 if (prev & bit)
2385 btrfs_clear_opt(fs_info->mount_opt, INODE_MAP_CACHE);
2386 prev &= ~bit;
2387
2388 bit = 1 << BTRFS_PENDING_COMMIT;
2389 if (prev & bit)
2390 btrfs_debug(fs_info, "pending commit done");
2391 prev &= ~bit;
2392
2393 if (prev)
2394 btrfs_warn(fs_info,
2395 "unknown pending changes left 0x%lx, ignoring", prev);
2396}
2397