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