1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
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>
16 #include "transaction.h"
19 #include "inode-map.h"
21 #include "dev-replace.h"
23 #include "block-group.h"
24 #include "space-info.h"
26 #define BTRFS_ROOT_TRANS_TAG 0
29 * Transaction states and transitions
31 * No running transaction (fs tree blocks are not modified)
34 * | Call start_transaction() variants. Except btrfs_join_transaction_nostart().
36 * Transaction N [[TRANS_STATE_RUNNING]]
38 * | New trans handles can be attached to transaction N by calling all
39 * | start_transaction() variants.
42 * | Call btrfs_commit_transaction() on any trans handle attached to
45 * Transaction N [[TRANS_STATE_COMMIT_START]]
47 * | Will wait for previous running transaction to completely finish if there
50 * | Then one of the following happes:
51 * | - Wait for all other trans handle holders to release.
52 * | The btrfs_commit_transaction() caller will do the commit work.
53 * | - Wait for current transaction to be committed by others.
54 * | Other btrfs_commit_transaction() caller will do the commit work.
56 * | At this stage, only btrfs_join_transaction*() variants can attach
57 * | to this running transaction.
58 * | All other variants will wait for current one to finish and attach to
62 * | Caller is chosen to commit transaction N, and all other trans handle
63 * | haven been released.
65 * Transaction N [[TRANS_STATE_COMMIT_DOING]]
67 * | The heavy lifting transaction work is started.
68 * | From running delayed refs (modifying extent tree) to creating pending
69 * | snapshots, running qgroups.
70 * | In short, modify supporting trees to reflect modifications of subvolume
73 * | At this stage, all start_transaction() calls will wait for this
74 * | transaction to finish and attach to transaction N+1.
77 * | Until all supporting trees are updated.
79 * Transaction N [[TRANS_STATE_UNBLOCKED]]
81 * | All needed trees are modified, thus we only [[TRANS_STATE_RUNNING]]
82 * | need to write them back to disk and update |
85 * | At this stage, new transaction is allowed to |
87 * | All new start_transaction() calls will be |
88 * | attached to transid N+1. |
91 * | Until all tree blocks are super blocks are |
92 * | written to block devices |
94 * Transaction N [[TRANS_STATE_COMPLETED]] V
95 * All tree blocks and super blocks are written. Transaction N+1
96 * This transaction is finished and all its [[TRANS_STATE_COMMIT_START]]
97 * data structures will be cleaned up. | Life goes on
99 static const unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = {
100 [TRANS_STATE_RUNNING] = 0U,
101 [TRANS_STATE_COMMIT_START] = (__TRANS_START | __TRANS_ATTACH),
102 [TRANS_STATE_COMMIT_DOING] = (__TRANS_START |
105 __TRANS_JOIN_NOSTART),
106 [TRANS_STATE_UNBLOCKED] = (__TRANS_START |
109 __TRANS_JOIN_NOLOCK |
110 __TRANS_JOIN_NOSTART),
111 [TRANS_STATE_COMPLETED] = (__TRANS_START |
114 __TRANS_JOIN_NOLOCK |
115 __TRANS_JOIN_NOSTART),
118 void btrfs_put_transaction(struct btrfs_transaction *transaction)
120 WARN_ON(refcount_read(&transaction->use_count) == 0);
121 if (refcount_dec_and_test(&transaction->use_count)) {
122 BUG_ON(!list_empty(&transaction->list));
123 WARN_ON(!RB_EMPTY_ROOT(
124 &transaction->delayed_refs.href_root.rb_root));
125 WARN_ON(!RB_EMPTY_ROOT(
126 &transaction->delayed_refs.dirty_extent_root));
127 if (transaction->delayed_refs.pending_csums)
128 btrfs_err(transaction->fs_info,
129 "pending csums is %llu",
130 transaction->delayed_refs.pending_csums);
132 * If any block groups are found in ->deleted_bgs then it's
133 * because the transaction was aborted and a commit did not
134 * happen (things failed before writing the new superblock
135 * and calling btrfs_finish_extent_commit()), so we can not
136 * discard the physical locations of the block groups.
138 while (!list_empty(&transaction->deleted_bgs)) {
139 struct btrfs_block_group *cache;
141 cache = list_first_entry(&transaction->deleted_bgs,
142 struct btrfs_block_group,
144 list_del_init(&cache->bg_list);
145 btrfs_unfreeze_block_group(cache);
146 btrfs_put_block_group(cache);
148 WARN_ON(!list_empty(&transaction->dev_update_list));
153 static noinline void switch_commit_roots(struct btrfs_trans_handle *trans)
155 struct btrfs_transaction *cur_trans = trans->transaction;
156 struct btrfs_fs_info *fs_info = trans->fs_info;
157 struct btrfs_root *root, *tmp;
159 down_write(&fs_info->commit_root_sem);
160 list_for_each_entry_safe(root, tmp, &cur_trans->switch_commits,
162 list_del_init(&root->dirty_list);
163 free_extent_buffer(root->commit_root);
164 root->commit_root = btrfs_root_node(root);
165 if (is_fstree(root->root_key.objectid))
166 btrfs_unpin_free_ino(root);
167 extent_io_tree_release(&root->dirty_log_pages);
168 btrfs_qgroup_clean_swapped_blocks(root);
171 /* We can free old roots now. */
172 spin_lock(&cur_trans->dropped_roots_lock);
173 while (!list_empty(&cur_trans->dropped_roots)) {
174 root = list_first_entry(&cur_trans->dropped_roots,
175 struct btrfs_root, root_list);
176 list_del_init(&root->root_list);
177 spin_unlock(&cur_trans->dropped_roots_lock);
178 btrfs_free_log(trans, root);
179 btrfs_drop_and_free_fs_root(fs_info, root);
180 spin_lock(&cur_trans->dropped_roots_lock);
182 spin_unlock(&cur_trans->dropped_roots_lock);
183 up_write(&fs_info->commit_root_sem);
186 static inline void extwriter_counter_inc(struct btrfs_transaction *trans,
189 if (type & TRANS_EXTWRITERS)
190 atomic_inc(&trans->num_extwriters);
193 static inline void extwriter_counter_dec(struct btrfs_transaction *trans,
196 if (type & TRANS_EXTWRITERS)
197 atomic_dec(&trans->num_extwriters);
200 static inline void extwriter_counter_init(struct btrfs_transaction *trans,
203 atomic_set(&trans->num_extwriters, ((type & TRANS_EXTWRITERS) ? 1 : 0));
206 static inline int extwriter_counter_read(struct btrfs_transaction *trans)
208 return atomic_read(&trans->num_extwriters);
212 * To be called after all the new block groups attached to the transaction
213 * handle have been created (btrfs_create_pending_block_groups()).
215 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
217 struct btrfs_fs_info *fs_info = trans->fs_info;
219 if (!trans->chunk_bytes_reserved)
222 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
224 btrfs_block_rsv_release(fs_info, &fs_info->chunk_block_rsv,
225 trans->chunk_bytes_reserved, NULL);
226 trans->chunk_bytes_reserved = 0;
230 * either allocate a new transaction or hop into the existing one
232 static noinline int join_transaction(struct btrfs_fs_info *fs_info,
235 struct btrfs_transaction *cur_trans;
237 spin_lock(&fs_info->trans_lock);
239 /* The file system has been taken offline. No new transactions. */
240 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
241 spin_unlock(&fs_info->trans_lock);
245 cur_trans = fs_info->running_transaction;
247 if (TRANS_ABORTED(cur_trans)) {
248 spin_unlock(&fs_info->trans_lock);
249 return cur_trans->aborted;
251 if (btrfs_blocked_trans_types[cur_trans->state] & type) {
252 spin_unlock(&fs_info->trans_lock);
255 refcount_inc(&cur_trans->use_count);
256 atomic_inc(&cur_trans->num_writers);
257 extwriter_counter_inc(cur_trans, type);
258 spin_unlock(&fs_info->trans_lock);
261 spin_unlock(&fs_info->trans_lock);
264 * If we are ATTACH, we just want to catch the current transaction,
265 * and commit it. If there is no transaction, just return ENOENT.
267 if (type == TRANS_ATTACH)
271 * JOIN_NOLOCK only happens during the transaction commit, so
272 * it is impossible that ->running_transaction is NULL
274 BUG_ON(type == TRANS_JOIN_NOLOCK);
276 cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS);
280 spin_lock(&fs_info->trans_lock);
281 if (fs_info->running_transaction) {
283 * someone started a transaction after we unlocked. Make sure
284 * to redo the checks above
288 } else if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
289 spin_unlock(&fs_info->trans_lock);
294 cur_trans->fs_info = fs_info;
295 atomic_set(&cur_trans->num_writers, 1);
296 extwriter_counter_init(cur_trans, type);
297 init_waitqueue_head(&cur_trans->writer_wait);
298 init_waitqueue_head(&cur_trans->commit_wait);
299 cur_trans->state = TRANS_STATE_RUNNING;
301 * One for this trans handle, one so it will live on until we
302 * commit the transaction.
304 refcount_set(&cur_trans->use_count, 2);
305 cur_trans->flags = 0;
306 cur_trans->start_time = ktime_get_seconds();
308 memset(&cur_trans->delayed_refs, 0, sizeof(cur_trans->delayed_refs));
310 cur_trans->delayed_refs.href_root = RB_ROOT_CACHED;
311 cur_trans->delayed_refs.dirty_extent_root = RB_ROOT;
312 atomic_set(&cur_trans->delayed_refs.num_entries, 0);
315 * although the tree mod log is per file system and not per transaction,
316 * the log must never go across transaction boundaries.
319 if (!list_empty(&fs_info->tree_mod_seq_list))
320 WARN(1, KERN_ERR "BTRFS: tree_mod_seq_list not empty when creating a fresh transaction\n");
321 if (!RB_EMPTY_ROOT(&fs_info->tree_mod_log))
322 WARN(1, KERN_ERR "BTRFS: tree_mod_log rb tree not empty when creating a fresh transaction\n");
323 atomic64_set(&fs_info->tree_mod_seq, 0);
325 spin_lock_init(&cur_trans->delayed_refs.lock);
327 INIT_LIST_HEAD(&cur_trans->pending_snapshots);
328 INIT_LIST_HEAD(&cur_trans->dev_update_list);
329 INIT_LIST_HEAD(&cur_trans->switch_commits);
330 INIT_LIST_HEAD(&cur_trans->dirty_bgs);
331 INIT_LIST_HEAD(&cur_trans->io_bgs);
332 INIT_LIST_HEAD(&cur_trans->dropped_roots);
333 mutex_init(&cur_trans->cache_write_mutex);
334 spin_lock_init(&cur_trans->dirty_bgs_lock);
335 INIT_LIST_HEAD(&cur_trans->deleted_bgs);
336 spin_lock_init(&cur_trans->dropped_roots_lock);
337 list_add_tail(&cur_trans->list, &fs_info->trans_list);
338 extent_io_tree_init(fs_info, &cur_trans->dirty_pages,
339 IO_TREE_TRANS_DIRTY_PAGES, fs_info->btree_inode);
340 extent_io_tree_init(fs_info, &cur_trans->pinned_extents,
341 IO_TREE_FS_PINNED_EXTENTS, NULL);
342 fs_info->generation++;
343 cur_trans->transid = fs_info->generation;
344 fs_info->running_transaction = cur_trans;
345 cur_trans->aborted = 0;
346 spin_unlock(&fs_info->trans_lock);
352 * This does all the record keeping required to make sure that a shareable root
353 * is properly recorded in a given transaction. This is required to make sure
354 * the old root from before we joined the transaction is deleted when the
355 * transaction commits.
357 static int record_root_in_trans(struct btrfs_trans_handle *trans,
358 struct btrfs_root *root,
361 struct btrfs_fs_info *fs_info = root->fs_info;
363 if ((test_bit(BTRFS_ROOT_SHAREABLE, &root->state) &&
364 root->last_trans < trans->transid) || force) {
365 WARN_ON(root == fs_info->extent_root);
366 WARN_ON(!force && root->commit_root != root->node);
369 * see below for IN_TRANS_SETUP usage rules
370 * we have the reloc mutex held now, so there
371 * is only one writer in this function
373 set_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
375 /* make sure readers find IN_TRANS_SETUP before
376 * they find our root->last_trans update
380 spin_lock(&fs_info->fs_roots_radix_lock);
381 if (root->last_trans == trans->transid && !force) {
382 spin_unlock(&fs_info->fs_roots_radix_lock);
385 radix_tree_tag_set(&fs_info->fs_roots_radix,
386 (unsigned long)root->root_key.objectid,
387 BTRFS_ROOT_TRANS_TAG);
388 spin_unlock(&fs_info->fs_roots_radix_lock);
389 root->last_trans = trans->transid;
391 /* this is pretty tricky. We don't want to
392 * take the relocation lock in btrfs_record_root_in_trans
393 * unless we're really doing the first setup for this root in
396 * Normally we'd use root->last_trans as a flag to decide
397 * if we want to take the expensive mutex.
399 * But, we have to set root->last_trans before we
400 * init the relocation root, otherwise, we trip over warnings
401 * in ctree.c. The solution used here is to flag ourselves
402 * with root IN_TRANS_SETUP. When this is 1, we're still
403 * fixing up the reloc trees and everyone must wait.
405 * When this is zero, they can trust root->last_trans and fly
406 * through btrfs_record_root_in_trans without having to take the
407 * lock. smp_wmb() makes sure that all the writes above are
408 * done before we pop in the zero below
410 btrfs_init_reloc_root(trans, root);
411 smp_mb__before_atomic();
412 clear_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
418 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
419 struct btrfs_root *root)
421 struct btrfs_fs_info *fs_info = root->fs_info;
422 struct btrfs_transaction *cur_trans = trans->transaction;
424 /* Add ourselves to the transaction dropped list */
425 spin_lock(&cur_trans->dropped_roots_lock);
426 list_add_tail(&root->root_list, &cur_trans->dropped_roots);
427 spin_unlock(&cur_trans->dropped_roots_lock);
429 /* Make sure we don't try to update the root at commit time */
430 spin_lock(&fs_info->fs_roots_radix_lock);
431 radix_tree_tag_clear(&fs_info->fs_roots_radix,
432 (unsigned long)root->root_key.objectid,
433 BTRFS_ROOT_TRANS_TAG);
434 spin_unlock(&fs_info->fs_roots_radix_lock);
437 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
438 struct btrfs_root *root)
440 struct btrfs_fs_info *fs_info = root->fs_info;
442 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
446 * see record_root_in_trans for comments about IN_TRANS_SETUP usage
450 if (root->last_trans == trans->transid &&
451 !test_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state))
454 mutex_lock(&fs_info->reloc_mutex);
455 record_root_in_trans(trans, root, 0);
456 mutex_unlock(&fs_info->reloc_mutex);
461 static inline int is_transaction_blocked(struct btrfs_transaction *trans)
463 return (trans->state >= TRANS_STATE_COMMIT_START &&
464 trans->state < TRANS_STATE_UNBLOCKED &&
465 !TRANS_ABORTED(trans));
468 /* wait for commit against the current transaction to become unblocked
469 * when this is done, it is safe to start a new transaction, but the current
470 * transaction might not be fully on disk.
472 static void wait_current_trans(struct btrfs_fs_info *fs_info)
474 struct btrfs_transaction *cur_trans;
476 spin_lock(&fs_info->trans_lock);
477 cur_trans = fs_info->running_transaction;
478 if (cur_trans && is_transaction_blocked(cur_trans)) {
479 refcount_inc(&cur_trans->use_count);
480 spin_unlock(&fs_info->trans_lock);
482 wait_event(fs_info->transaction_wait,
483 cur_trans->state >= TRANS_STATE_UNBLOCKED ||
484 TRANS_ABORTED(cur_trans));
485 btrfs_put_transaction(cur_trans);
487 spin_unlock(&fs_info->trans_lock);
491 static int may_wait_transaction(struct btrfs_fs_info *fs_info, int type)
493 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
496 if (type == TRANS_START)
502 static inline bool need_reserve_reloc_root(struct btrfs_root *root)
504 struct btrfs_fs_info *fs_info = root->fs_info;
506 if (!fs_info->reloc_ctl ||
507 !test_bit(BTRFS_ROOT_SHAREABLE, &root->state) ||
508 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
515 static struct btrfs_trans_handle *
516 start_transaction(struct btrfs_root *root, unsigned int num_items,
517 unsigned int type, enum btrfs_reserve_flush_enum flush,
518 bool enforce_qgroups)
520 struct btrfs_fs_info *fs_info = root->fs_info;
521 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
522 struct btrfs_trans_handle *h;
523 struct btrfs_transaction *cur_trans;
525 u64 qgroup_reserved = 0;
526 bool reloc_reserved = false;
527 bool do_chunk_alloc = false;
530 /* Send isn't supposed to start transactions. */
531 ASSERT(current->journal_info != BTRFS_SEND_TRANS_STUB);
533 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
534 return ERR_PTR(-EROFS);
536 if (current->journal_info) {
537 WARN_ON(type & TRANS_EXTWRITERS);
538 h = current->journal_info;
539 refcount_inc(&h->use_count);
540 WARN_ON(refcount_read(&h->use_count) > 2);
541 h->orig_rsv = h->block_rsv;
547 * Do the reservation before we join the transaction so we can do all
548 * the appropriate flushing if need be.
550 if (num_items && root != fs_info->chunk_root) {
551 struct btrfs_block_rsv *rsv = &fs_info->trans_block_rsv;
552 u64 delayed_refs_bytes = 0;
554 qgroup_reserved = num_items * fs_info->nodesize;
555 ret = btrfs_qgroup_reserve_meta_pertrans(root, qgroup_reserved,
561 * We want to reserve all the bytes we may need all at once, so
562 * we only do 1 enospc flushing cycle per transaction start. We
563 * accomplish this by simply assuming we'll do 2 x num_items
564 * worth of delayed refs updates in this trans handle, and
565 * refill that amount for whatever is missing in the reserve.
567 num_bytes = btrfs_calc_insert_metadata_size(fs_info, num_items);
568 if (flush == BTRFS_RESERVE_FLUSH_ALL &&
569 delayed_refs_rsv->full == 0) {
570 delayed_refs_bytes = num_bytes;
575 * Do the reservation for the relocation root creation
577 if (need_reserve_reloc_root(root)) {
578 num_bytes += fs_info->nodesize;
579 reloc_reserved = true;
582 ret = btrfs_block_rsv_add(root, rsv, num_bytes, flush);
585 if (delayed_refs_bytes) {
586 btrfs_migrate_to_delayed_refs_rsv(fs_info, rsv,
588 num_bytes -= delayed_refs_bytes;
591 if (rsv->space_info->force_alloc)
592 do_chunk_alloc = true;
593 } else if (num_items == 0 && flush == BTRFS_RESERVE_FLUSH_ALL &&
594 !delayed_refs_rsv->full) {
596 * Some people call with btrfs_start_transaction(root, 0)
597 * because they can be throttled, but have some other mechanism
598 * for reserving space. We still want these guys to refill the
599 * delayed block_rsv so just add 1 items worth of reservation
602 ret = btrfs_delayed_refs_rsv_refill(fs_info, flush);
607 h = kmem_cache_zalloc(btrfs_trans_handle_cachep, GFP_NOFS);
614 * If we are JOIN_NOLOCK we're already committing a transaction and
615 * waiting on this guy, so we don't need to do the sb_start_intwrite
616 * because we're already holding a ref. We need this because we could
617 * have raced in and did an fsync() on a file which can kick a commit
618 * and then we deadlock with somebody doing a freeze.
620 * If we are ATTACH, it means we just want to catch the current
621 * transaction and commit it, so we needn't do sb_start_intwrite().
623 if (type & __TRANS_FREEZABLE)
624 sb_start_intwrite(fs_info->sb);
626 if (may_wait_transaction(fs_info, type))
627 wait_current_trans(fs_info);
630 ret = join_transaction(fs_info, type);
632 wait_current_trans(fs_info);
633 if (unlikely(type == TRANS_ATTACH ||
634 type == TRANS_JOIN_NOSTART))
637 } while (ret == -EBUSY);
642 cur_trans = fs_info->running_transaction;
644 h->transid = cur_trans->transid;
645 h->transaction = cur_trans;
647 refcount_set(&h->use_count, 1);
648 h->fs_info = root->fs_info;
651 h->can_flush_pending_bgs = true;
652 INIT_LIST_HEAD(&h->new_bgs);
655 if (cur_trans->state >= TRANS_STATE_COMMIT_START &&
656 may_wait_transaction(fs_info, type)) {
657 current->journal_info = h;
658 btrfs_commit_transaction(h);
663 trace_btrfs_space_reservation(fs_info, "transaction",
664 h->transid, num_bytes, 1);
665 h->block_rsv = &fs_info->trans_block_rsv;
666 h->bytes_reserved = num_bytes;
667 h->reloc_reserved = reloc_reserved;
671 if (!current->journal_info)
672 current->journal_info = h;
675 * If the space_info is marked ALLOC_FORCE then we'll get upgraded to
676 * ALLOC_FORCE the first run through, and then we won't allocate for
677 * anybody else who races in later. We don't care about the return
680 if (do_chunk_alloc && num_bytes) {
681 u64 flags = h->block_rsv->space_info->flags;
683 btrfs_chunk_alloc(h, btrfs_get_alloc_profile(fs_info, flags),
684 CHUNK_ALLOC_NO_FORCE);
688 * btrfs_record_root_in_trans() needs to alloc new extents, and may
689 * call btrfs_join_transaction() while we're also starting a
692 * Thus it need to be called after current->journal_info initialized,
693 * or we can deadlock.
695 btrfs_record_root_in_trans(h, root);
700 if (type & __TRANS_FREEZABLE)
701 sb_end_intwrite(fs_info->sb);
702 kmem_cache_free(btrfs_trans_handle_cachep, h);
705 btrfs_block_rsv_release(fs_info, &fs_info->trans_block_rsv,
708 btrfs_qgroup_free_meta_pertrans(root, qgroup_reserved);
712 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
713 unsigned int num_items)
715 return start_transaction(root, num_items, TRANS_START,
716 BTRFS_RESERVE_FLUSH_ALL, true);
719 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
720 struct btrfs_root *root,
721 unsigned int num_items)
723 return start_transaction(root, num_items, TRANS_START,
724 BTRFS_RESERVE_FLUSH_ALL_STEAL, false);
727 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root)
729 return start_transaction(root, 0, TRANS_JOIN, BTRFS_RESERVE_NO_FLUSH,
733 struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root)
735 return start_transaction(root, 0, TRANS_JOIN_NOLOCK,
736 BTRFS_RESERVE_NO_FLUSH, true);
740 * Similar to regular join but it never starts a transaction when none is
741 * running or after waiting for the current one to finish.
743 struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root)
745 return start_transaction(root, 0, TRANS_JOIN_NOSTART,
746 BTRFS_RESERVE_NO_FLUSH, true);
750 * btrfs_attach_transaction() - catch the running transaction
752 * It is used when we want to commit the current the transaction, but
753 * don't want to start a new one.
755 * Note: If this function return -ENOENT, it just means there is no
756 * running transaction. But it is possible that the inactive transaction
757 * is still in the memory, not fully on disk. If you hope there is no
758 * inactive transaction in the fs when -ENOENT is returned, you should
760 * btrfs_attach_transaction_barrier()
762 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root)
764 return start_transaction(root, 0, TRANS_ATTACH,
765 BTRFS_RESERVE_NO_FLUSH, true);
769 * btrfs_attach_transaction_barrier() - catch the running transaction
771 * It is similar to the above function, the difference is this one
772 * will wait for all the inactive transactions until they fully
775 struct btrfs_trans_handle *
776 btrfs_attach_transaction_barrier(struct btrfs_root *root)
778 struct btrfs_trans_handle *trans;
780 trans = start_transaction(root, 0, TRANS_ATTACH,
781 BTRFS_RESERVE_NO_FLUSH, true);
782 if (trans == ERR_PTR(-ENOENT))
783 btrfs_wait_for_commit(root->fs_info, 0);
788 /* wait for a transaction commit to be fully complete */
789 static noinline void wait_for_commit(struct btrfs_transaction *commit)
791 wait_event(commit->commit_wait, commit->state == TRANS_STATE_COMPLETED);
794 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid)
796 struct btrfs_transaction *cur_trans = NULL, *t;
800 if (transid <= fs_info->last_trans_committed)
803 /* find specified transaction */
804 spin_lock(&fs_info->trans_lock);
805 list_for_each_entry(t, &fs_info->trans_list, list) {
806 if (t->transid == transid) {
808 refcount_inc(&cur_trans->use_count);
812 if (t->transid > transid) {
817 spin_unlock(&fs_info->trans_lock);
820 * The specified transaction doesn't exist, or we
821 * raced with btrfs_commit_transaction
824 if (transid > fs_info->last_trans_committed)
829 /* find newest transaction that is committing | committed */
830 spin_lock(&fs_info->trans_lock);
831 list_for_each_entry_reverse(t, &fs_info->trans_list,
833 if (t->state >= TRANS_STATE_COMMIT_START) {
834 if (t->state == TRANS_STATE_COMPLETED)
837 refcount_inc(&cur_trans->use_count);
841 spin_unlock(&fs_info->trans_lock);
843 goto out; /* nothing committing|committed */
846 wait_for_commit(cur_trans);
847 btrfs_put_transaction(cur_trans);
852 void btrfs_throttle(struct btrfs_fs_info *fs_info)
854 wait_current_trans(fs_info);
857 static int should_end_transaction(struct btrfs_trans_handle *trans)
859 struct btrfs_fs_info *fs_info = trans->fs_info;
861 if (btrfs_check_space_for_delayed_refs(fs_info))
864 return !!btrfs_block_rsv_check(&fs_info->global_block_rsv, 5);
867 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans)
869 struct btrfs_transaction *cur_trans = trans->transaction;
872 if (cur_trans->state >= TRANS_STATE_COMMIT_START ||
873 cur_trans->delayed_refs.flushing)
876 return should_end_transaction(trans);
879 static void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans)
882 struct btrfs_fs_info *fs_info = trans->fs_info;
884 if (!trans->block_rsv) {
885 ASSERT(!trans->bytes_reserved);
889 if (!trans->bytes_reserved)
892 ASSERT(trans->block_rsv == &fs_info->trans_block_rsv);
893 trace_btrfs_space_reservation(fs_info, "transaction",
894 trans->transid, trans->bytes_reserved, 0);
895 btrfs_block_rsv_release(fs_info, trans->block_rsv,
896 trans->bytes_reserved, NULL);
897 trans->bytes_reserved = 0;
900 static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
903 struct btrfs_fs_info *info = trans->fs_info;
904 struct btrfs_transaction *cur_trans = trans->transaction;
907 if (refcount_read(&trans->use_count) > 1) {
908 refcount_dec(&trans->use_count);
909 trans->block_rsv = trans->orig_rsv;
913 btrfs_trans_release_metadata(trans);
914 trans->block_rsv = NULL;
916 btrfs_create_pending_block_groups(trans);
918 btrfs_trans_release_chunk_metadata(trans);
920 if (trans->type & __TRANS_FREEZABLE)
921 sb_end_intwrite(info->sb);
923 WARN_ON(cur_trans != info->running_transaction);
924 WARN_ON(atomic_read(&cur_trans->num_writers) < 1);
925 atomic_dec(&cur_trans->num_writers);
926 extwriter_counter_dec(cur_trans, trans->type);
928 cond_wake_up(&cur_trans->writer_wait);
929 btrfs_put_transaction(cur_trans);
931 if (current->journal_info == trans)
932 current->journal_info = NULL;
935 btrfs_run_delayed_iputs(info);
937 if (TRANS_ABORTED(trans) ||
938 test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) {
939 wake_up_process(info->transaction_kthread);
940 if (TRANS_ABORTED(trans))
941 err = trans->aborted;
946 kmem_cache_free(btrfs_trans_handle_cachep, trans);
950 int btrfs_end_transaction(struct btrfs_trans_handle *trans)
952 return __btrfs_end_transaction(trans, 0);
955 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans)
957 return __btrfs_end_transaction(trans, 1);
961 * when btree blocks are allocated, they have some corresponding bits set for
962 * them in one of two extent_io trees. This is used to make sure all of
963 * those extents are sent to disk but does not wait on them
965 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
966 struct extent_io_tree *dirty_pages, int mark)
970 struct address_space *mapping = fs_info->btree_inode->i_mapping;
971 struct extent_state *cached_state = NULL;
975 atomic_inc(&BTRFS_I(fs_info->btree_inode)->sync_writers);
976 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
977 mark, &cached_state)) {
978 bool wait_writeback = false;
980 err = convert_extent_bit(dirty_pages, start, end,
982 mark, &cached_state);
984 * convert_extent_bit can return -ENOMEM, which is most of the
985 * time a temporary error. So when it happens, ignore the error
986 * and wait for writeback of this range to finish - because we
987 * failed to set the bit EXTENT_NEED_WAIT for the range, a call
988 * to __btrfs_wait_marked_extents() would not know that
989 * writeback for this range started and therefore wouldn't
990 * wait for it to finish - we don't want to commit a
991 * superblock that points to btree nodes/leafs for which
992 * writeback hasn't finished yet (and without errors).
993 * We cleanup any entries left in the io tree when committing
994 * the transaction (through extent_io_tree_release()).
996 if (err == -ENOMEM) {
998 wait_writeback = true;
1001 err = filemap_fdatawrite_range(mapping, start, end);
1004 else if (wait_writeback)
1005 werr = filemap_fdatawait_range(mapping, start, end);
1006 free_extent_state(cached_state);
1007 cached_state = NULL;
1011 atomic_dec(&BTRFS_I(fs_info->btree_inode)->sync_writers);
1016 * when btree blocks are allocated, they have some corresponding bits set for
1017 * them in one of two extent_io trees. This is used to make sure all of
1018 * those extents are on disk for transaction or log commit. We wait
1019 * on all the pages and clear them from the dirty pages state tree
1021 static int __btrfs_wait_marked_extents(struct btrfs_fs_info *fs_info,
1022 struct extent_io_tree *dirty_pages)
1026 struct address_space *mapping = fs_info->btree_inode->i_mapping;
1027 struct extent_state *cached_state = NULL;
1031 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
1032 EXTENT_NEED_WAIT, &cached_state)) {
1034 * Ignore -ENOMEM errors returned by clear_extent_bit().
1035 * When committing the transaction, we'll remove any entries
1036 * left in the io tree. For a log commit, we don't remove them
1037 * after committing the log because the tree can be accessed
1038 * concurrently - we do it only at transaction commit time when
1039 * it's safe to do it (through extent_io_tree_release()).
1041 err = clear_extent_bit(dirty_pages, start, end,
1042 EXTENT_NEED_WAIT, 0, 0, &cached_state);
1046 err = filemap_fdatawait_range(mapping, start, end);
1049 free_extent_state(cached_state);
1050 cached_state = NULL;
1059 static int btrfs_wait_extents(struct btrfs_fs_info *fs_info,
1060 struct extent_io_tree *dirty_pages)
1062 bool errors = false;
1065 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
1066 if (test_and_clear_bit(BTRFS_FS_BTREE_ERR, &fs_info->flags))
1074 int btrfs_wait_tree_log_extents(struct btrfs_root *log_root, int mark)
1076 struct btrfs_fs_info *fs_info = log_root->fs_info;
1077 struct extent_io_tree *dirty_pages = &log_root->dirty_log_pages;
1078 bool errors = false;
1081 ASSERT(log_root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
1083 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
1084 if ((mark & EXTENT_DIRTY) &&
1085 test_and_clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags))
1088 if ((mark & EXTENT_NEW) &&
1089 test_and_clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags))
1098 * When btree blocks are allocated the corresponding extents are marked dirty.
1099 * This function ensures such extents are persisted on disk for transaction or
1102 * @trans: transaction whose dirty pages we'd like to write
1104 static int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans)
1108 struct extent_io_tree *dirty_pages = &trans->transaction->dirty_pages;
1109 struct btrfs_fs_info *fs_info = trans->fs_info;
1110 struct blk_plug plug;
1112 blk_start_plug(&plug);
1113 ret = btrfs_write_marked_extents(fs_info, dirty_pages, EXTENT_DIRTY);
1114 blk_finish_plug(&plug);
1115 ret2 = btrfs_wait_extents(fs_info, dirty_pages);
1117 extent_io_tree_release(&trans->transaction->dirty_pages);
1128 * this is used to update the root pointer in the tree of tree roots.
1130 * But, in the case of the extent allocation tree, updating the root
1131 * pointer may allocate blocks which may change the root of the extent
1134 * So, this loops and repeats and makes sure the cowonly root didn't
1135 * change while the root pointer was being updated in the metadata.
1137 static int update_cowonly_root(struct btrfs_trans_handle *trans,
1138 struct btrfs_root *root)
1141 u64 old_root_bytenr;
1143 struct btrfs_fs_info *fs_info = root->fs_info;
1144 struct btrfs_root *tree_root = fs_info->tree_root;
1146 old_root_used = btrfs_root_used(&root->root_item);
1149 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
1150 if (old_root_bytenr == root->node->start &&
1151 old_root_used == btrfs_root_used(&root->root_item))
1154 btrfs_set_root_node(&root->root_item, root->node);
1155 ret = btrfs_update_root(trans, tree_root,
1161 old_root_used = btrfs_root_used(&root->root_item);
1168 * update all the cowonly tree roots on disk
1170 * The error handling in this function may not be obvious. Any of the
1171 * failures will cause the file system to go offline. We still need
1172 * to clean up the delayed refs.
1174 static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans)
1176 struct btrfs_fs_info *fs_info = trans->fs_info;
1177 struct list_head *dirty_bgs = &trans->transaction->dirty_bgs;
1178 struct list_head *io_bgs = &trans->transaction->io_bgs;
1179 struct list_head *next;
1180 struct extent_buffer *eb;
1183 eb = btrfs_lock_root_node(fs_info->tree_root);
1184 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL,
1186 btrfs_tree_unlock(eb);
1187 free_extent_buffer(eb);
1192 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1196 ret = btrfs_run_dev_stats(trans);
1199 ret = btrfs_run_dev_replace(trans);
1202 ret = btrfs_run_qgroups(trans);
1206 ret = btrfs_setup_space_cache(trans);
1210 /* run_qgroups might have added some more refs */
1211 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1215 while (!list_empty(&fs_info->dirty_cowonly_roots)) {
1216 struct btrfs_root *root;
1217 next = fs_info->dirty_cowonly_roots.next;
1218 list_del_init(next);
1219 root = list_entry(next, struct btrfs_root, dirty_list);
1220 clear_bit(BTRFS_ROOT_DIRTY, &root->state);
1222 if (root != fs_info->extent_root)
1223 list_add_tail(&root->dirty_list,
1224 &trans->transaction->switch_commits);
1225 ret = update_cowonly_root(trans, root);
1228 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1233 while (!list_empty(dirty_bgs) || !list_empty(io_bgs)) {
1234 ret = btrfs_write_dirty_block_groups(trans);
1237 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1242 if (!list_empty(&fs_info->dirty_cowonly_roots))
1245 list_add_tail(&fs_info->extent_root->dirty_list,
1246 &trans->transaction->switch_commits);
1248 /* Update dev-replace pointer once everything is committed */
1249 fs_info->dev_replace.committed_cursor_left =
1250 fs_info->dev_replace.cursor_left_last_write_of_item;
1256 * dead roots are old snapshots that need to be deleted. This allocates
1257 * a dirty root struct and adds it into the list of dead roots that need to
1260 void btrfs_add_dead_root(struct btrfs_root *root)
1262 struct btrfs_fs_info *fs_info = root->fs_info;
1264 spin_lock(&fs_info->trans_lock);
1265 if (list_empty(&root->root_list)) {
1266 btrfs_grab_root(root);
1267 list_add_tail(&root->root_list, &fs_info->dead_roots);
1269 spin_unlock(&fs_info->trans_lock);
1273 * update all the cowonly tree roots on disk
1275 static noinline int commit_fs_roots(struct btrfs_trans_handle *trans)
1277 struct btrfs_fs_info *fs_info = trans->fs_info;
1278 struct btrfs_root *gang[8];
1283 spin_lock(&fs_info->fs_roots_radix_lock);
1285 ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
1288 BTRFS_ROOT_TRANS_TAG);
1291 for (i = 0; i < ret; i++) {
1292 struct btrfs_root *root = gang[i];
1293 radix_tree_tag_clear(&fs_info->fs_roots_radix,
1294 (unsigned long)root->root_key.objectid,
1295 BTRFS_ROOT_TRANS_TAG);
1296 spin_unlock(&fs_info->fs_roots_radix_lock);
1298 btrfs_free_log(trans, root);
1299 btrfs_update_reloc_root(trans, root);
1301 btrfs_save_ino_cache(root, trans);
1303 /* see comments in should_cow_block() */
1304 clear_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1305 smp_mb__after_atomic();
1307 if (root->commit_root != root->node) {
1308 list_add_tail(&root->dirty_list,
1309 &trans->transaction->switch_commits);
1310 btrfs_set_root_node(&root->root_item,
1314 err = btrfs_update_root(trans, fs_info->tree_root,
1317 spin_lock(&fs_info->fs_roots_radix_lock);
1320 btrfs_qgroup_free_meta_all_pertrans(root);
1323 spin_unlock(&fs_info->fs_roots_radix_lock);
1328 * defrag a given btree.
1329 * Every leaf in the btree is read and defragged.
1331 int btrfs_defrag_root(struct btrfs_root *root)
1333 struct btrfs_fs_info *info = root->fs_info;
1334 struct btrfs_trans_handle *trans;
1337 if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state))
1341 trans = btrfs_start_transaction(root, 0);
1343 return PTR_ERR(trans);
1345 ret = btrfs_defrag_leaves(trans, root);
1347 btrfs_end_transaction(trans);
1348 btrfs_btree_balance_dirty(info);
1351 if (btrfs_fs_closing(info) || ret != -EAGAIN)
1354 if (btrfs_defrag_cancelled(info)) {
1355 btrfs_debug(info, "defrag_root cancelled");
1360 clear_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state);
1365 * Do all special snapshot related qgroup dirty hack.
1367 * Will do all needed qgroup inherit and dirty hack like switch commit
1368 * roots inside one transaction and write all btree into disk, to make
1371 static int qgroup_account_snapshot(struct btrfs_trans_handle *trans,
1372 struct btrfs_root *src,
1373 struct btrfs_root *parent,
1374 struct btrfs_qgroup_inherit *inherit,
1377 struct btrfs_fs_info *fs_info = src->fs_info;
1381 * Save some performance in the case that qgroups are not
1382 * enabled. If this check races with the ioctl, rescan will
1385 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1389 * Ensure dirty @src will be committed. Or, after coming
1390 * commit_fs_roots() and switch_commit_roots(), any dirty but not
1391 * recorded root will never be updated again, causing an outdated root
1394 record_root_in_trans(trans, src, 1);
1397 * We are going to commit transaction, see btrfs_commit_transaction()
1398 * comment for reason locking tree_log_mutex
1400 mutex_lock(&fs_info->tree_log_mutex);
1402 ret = commit_fs_roots(trans);
1405 ret = btrfs_qgroup_account_extents(trans);
1409 /* Now qgroup are all updated, we can inherit it to new qgroups */
1410 ret = btrfs_qgroup_inherit(trans, src->root_key.objectid, dst_objectid,
1416 * Now we do a simplified commit transaction, which will:
1417 * 1) commit all subvolume and extent tree
1418 * To ensure all subvolume and extent tree have a valid
1419 * commit_root to accounting later insert_dir_item()
1420 * 2) write all btree blocks onto disk
1421 * This is to make sure later btree modification will be cowed
1422 * Or commit_root can be populated and cause wrong qgroup numbers
1423 * In this simplified commit, we don't really care about other trees
1424 * like chunk and root tree, as they won't affect qgroup.
1425 * And we don't write super to avoid half committed status.
1427 ret = commit_cowonly_roots(trans);
1430 switch_commit_roots(trans);
1431 ret = btrfs_write_and_wait_transaction(trans);
1433 btrfs_handle_fs_error(fs_info, ret,
1434 "Error while writing out transaction for qgroup");
1437 mutex_unlock(&fs_info->tree_log_mutex);
1440 * Force parent root to be updated, as we recorded it before so its
1441 * last_trans == cur_transid.
1442 * Or it won't be committed again onto disk after later
1446 record_root_in_trans(trans, parent, 1);
1451 * new snapshots need to be created at a very specific time in the
1452 * transaction commit. This does the actual creation.
1455 * If the error which may affect the commitment of the current transaction
1456 * happens, we should return the error number. If the error which just affect
1457 * the creation of the pending snapshots, just return 0.
1459 static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
1460 struct btrfs_pending_snapshot *pending)
1463 struct btrfs_fs_info *fs_info = trans->fs_info;
1464 struct btrfs_key key;
1465 struct btrfs_root_item *new_root_item;
1466 struct btrfs_root *tree_root = fs_info->tree_root;
1467 struct btrfs_root *root = pending->root;
1468 struct btrfs_root *parent_root;
1469 struct btrfs_block_rsv *rsv;
1470 struct inode *parent_inode;
1471 struct btrfs_path *path;
1472 struct btrfs_dir_item *dir_item;
1473 struct dentry *dentry;
1474 struct extent_buffer *tmp;
1475 struct extent_buffer *old;
1476 struct timespec64 cur_time;
1483 ASSERT(pending->path);
1484 path = pending->path;
1486 ASSERT(pending->root_item);
1487 new_root_item = pending->root_item;
1489 pending->error = btrfs_find_free_objectid(tree_root, &objectid);
1491 goto no_free_objectid;
1494 * Make qgroup to skip current new snapshot's qgroupid, as it is
1495 * accounted by later btrfs_qgroup_inherit().
1497 btrfs_set_skip_qgroup(trans, objectid);
1499 btrfs_reloc_pre_snapshot(pending, &to_reserve);
1501 if (to_reserve > 0) {
1502 pending->error = btrfs_block_rsv_add(root,
1503 &pending->block_rsv,
1505 BTRFS_RESERVE_NO_FLUSH);
1507 goto clear_skip_qgroup;
1510 key.objectid = objectid;
1511 key.offset = (u64)-1;
1512 key.type = BTRFS_ROOT_ITEM_KEY;
1514 rsv = trans->block_rsv;
1515 trans->block_rsv = &pending->block_rsv;
1516 trans->bytes_reserved = trans->block_rsv->reserved;
1517 trace_btrfs_space_reservation(fs_info, "transaction",
1519 trans->bytes_reserved, 1);
1520 dentry = pending->dentry;
1521 parent_inode = pending->dir;
1522 parent_root = BTRFS_I(parent_inode)->root;
1523 record_root_in_trans(trans, parent_root, 0);
1525 cur_time = current_time(parent_inode);
1528 * insert the directory item
1530 ret = btrfs_set_inode_index(BTRFS_I(parent_inode), &index);
1531 BUG_ON(ret); /* -ENOMEM */
1533 /* check if there is a file/dir which has the same name. */
1534 dir_item = btrfs_lookup_dir_item(NULL, parent_root, path,
1535 btrfs_ino(BTRFS_I(parent_inode)),
1536 dentry->d_name.name,
1537 dentry->d_name.len, 0);
1538 if (dir_item != NULL && !IS_ERR(dir_item)) {
1539 pending->error = -EEXIST;
1540 goto dir_item_existed;
1541 } else if (IS_ERR(dir_item)) {
1542 ret = PTR_ERR(dir_item);
1543 btrfs_abort_transaction(trans, ret);
1546 btrfs_release_path(path);
1549 * pull in the delayed directory update
1550 * and the delayed inode item
1551 * otherwise we corrupt the FS during
1554 ret = btrfs_run_delayed_items(trans);
1555 if (ret) { /* Transaction aborted */
1556 btrfs_abort_transaction(trans, ret);
1560 record_root_in_trans(trans, root, 0);
1561 btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
1562 memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
1563 btrfs_check_and_init_root_item(new_root_item);
1565 root_flags = btrfs_root_flags(new_root_item);
1566 if (pending->readonly)
1567 root_flags |= BTRFS_ROOT_SUBVOL_RDONLY;
1569 root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY;
1570 btrfs_set_root_flags(new_root_item, root_flags);
1572 btrfs_set_root_generation_v2(new_root_item,
1574 generate_random_guid(new_root_item->uuid);
1575 memcpy(new_root_item->parent_uuid, root->root_item.uuid,
1577 if (!(root_flags & BTRFS_ROOT_SUBVOL_RDONLY)) {
1578 memset(new_root_item->received_uuid, 0,
1579 sizeof(new_root_item->received_uuid));
1580 memset(&new_root_item->stime, 0, sizeof(new_root_item->stime));
1581 memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime));
1582 btrfs_set_root_stransid(new_root_item, 0);
1583 btrfs_set_root_rtransid(new_root_item, 0);
1585 btrfs_set_stack_timespec_sec(&new_root_item->otime, cur_time.tv_sec);
1586 btrfs_set_stack_timespec_nsec(&new_root_item->otime, cur_time.tv_nsec);
1587 btrfs_set_root_otransid(new_root_item, trans->transid);
1589 old = btrfs_lock_root_node(root);
1590 ret = btrfs_cow_block(trans, root, old, NULL, 0, &old);
1592 btrfs_tree_unlock(old);
1593 free_extent_buffer(old);
1594 btrfs_abort_transaction(trans, ret);
1598 btrfs_set_lock_blocking_write(old);
1600 ret = btrfs_copy_root(trans, root, old, &tmp, objectid);
1601 /* clean up in any case */
1602 btrfs_tree_unlock(old);
1603 free_extent_buffer(old);
1605 btrfs_abort_transaction(trans, ret);
1608 /* see comments in should_cow_block() */
1609 set_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1612 btrfs_set_root_node(new_root_item, tmp);
1613 /* record when the snapshot was created in key.offset */
1614 key.offset = trans->transid;
1615 ret = btrfs_insert_root(trans, tree_root, &key, new_root_item);
1616 btrfs_tree_unlock(tmp);
1617 free_extent_buffer(tmp);
1619 btrfs_abort_transaction(trans, ret);
1624 * insert root back/forward references
1626 ret = btrfs_add_root_ref(trans, objectid,
1627 parent_root->root_key.objectid,
1628 btrfs_ino(BTRFS_I(parent_inode)), index,
1629 dentry->d_name.name, dentry->d_name.len);
1631 btrfs_abort_transaction(trans, ret);
1635 key.offset = (u64)-1;
1636 pending->snap = btrfs_get_new_fs_root(fs_info, objectid, pending->anon_dev);
1637 if (IS_ERR(pending->snap)) {
1638 ret = PTR_ERR(pending->snap);
1639 btrfs_abort_transaction(trans, ret);
1643 ret = btrfs_reloc_post_snapshot(trans, pending);
1645 btrfs_abort_transaction(trans, ret);
1649 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1651 btrfs_abort_transaction(trans, ret);
1656 * Do special qgroup accounting for snapshot, as we do some qgroup
1657 * snapshot hack to do fast snapshot.
1658 * To co-operate with that hack, we do hack again.
1659 * Or snapshot will be greatly slowed down by a subtree qgroup rescan
1661 ret = qgroup_account_snapshot(trans, root, parent_root,
1662 pending->inherit, objectid);
1666 ret = btrfs_insert_dir_item(trans, dentry->d_name.name,
1667 dentry->d_name.len, BTRFS_I(parent_inode),
1668 &key, BTRFS_FT_DIR, index);
1669 /* We have check then name at the beginning, so it is impossible. */
1670 BUG_ON(ret == -EEXIST || ret == -EOVERFLOW);
1672 btrfs_abort_transaction(trans, ret);
1676 btrfs_i_size_write(BTRFS_I(parent_inode), parent_inode->i_size +
1677 dentry->d_name.len * 2);
1678 parent_inode->i_mtime = parent_inode->i_ctime =
1679 current_time(parent_inode);
1680 ret = btrfs_update_inode_fallback(trans, parent_root, parent_inode);
1682 btrfs_abort_transaction(trans, ret);
1685 ret = btrfs_uuid_tree_add(trans, new_root_item->uuid,
1686 BTRFS_UUID_KEY_SUBVOL,
1689 btrfs_abort_transaction(trans, ret);
1692 if (!btrfs_is_empty_uuid(new_root_item->received_uuid)) {
1693 ret = btrfs_uuid_tree_add(trans, new_root_item->received_uuid,
1694 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
1696 if (ret && ret != -EEXIST) {
1697 btrfs_abort_transaction(trans, ret);
1702 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1704 btrfs_abort_transaction(trans, ret);
1709 pending->error = ret;
1711 trans->block_rsv = rsv;
1712 trans->bytes_reserved = 0;
1714 btrfs_clear_skip_qgroup(trans);
1716 kfree(new_root_item);
1717 pending->root_item = NULL;
1718 btrfs_free_path(path);
1719 pending->path = NULL;
1725 * create all the snapshots we've scheduled for creation
1727 static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans)
1729 struct btrfs_pending_snapshot *pending, *next;
1730 struct list_head *head = &trans->transaction->pending_snapshots;
1733 list_for_each_entry_safe(pending, next, head, list) {
1734 list_del(&pending->list);
1735 ret = create_pending_snapshot(trans, pending);
1742 static void update_super_roots(struct btrfs_fs_info *fs_info)
1744 struct btrfs_root_item *root_item;
1745 struct btrfs_super_block *super;
1747 super = fs_info->super_copy;
1749 root_item = &fs_info->chunk_root->root_item;
1750 super->chunk_root = root_item->bytenr;
1751 super->chunk_root_generation = root_item->generation;
1752 super->chunk_root_level = root_item->level;
1754 root_item = &fs_info->tree_root->root_item;
1755 super->root = root_item->bytenr;
1756 super->generation = root_item->generation;
1757 super->root_level = root_item->level;
1758 if (btrfs_test_opt(fs_info, SPACE_CACHE))
1759 super->cache_generation = root_item->generation;
1760 if (test_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags))
1761 super->uuid_tree_generation = root_item->generation;
1764 int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
1766 struct btrfs_transaction *trans;
1769 spin_lock(&info->trans_lock);
1770 trans = info->running_transaction;
1772 ret = (trans->state >= TRANS_STATE_COMMIT_START);
1773 spin_unlock(&info->trans_lock);
1777 int btrfs_transaction_blocked(struct btrfs_fs_info *info)
1779 struct btrfs_transaction *trans;
1782 spin_lock(&info->trans_lock);
1783 trans = info->running_transaction;
1785 ret = is_transaction_blocked(trans);
1786 spin_unlock(&info->trans_lock);
1791 * wait for the current transaction commit to start and block subsequent
1794 static void wait_current_trans_commit_start(struct btrfs_fs_info *fs_info,
1795 struct btrfs_transaction *trans)
1797 wait_event(fs_info->transaction_blocked_wait,
1798 trans->state >= TRANS_STATE_COMMIT_START ||
1799 TRANS_ABORTED(trans));
1803 * wait for the current transaction to start and then become unblocked.
1806 static void wait_current_trans_commit_start_and_unblock(
1807 struct btrfs_fs_info *fs_info,
1808 struct btrfs_transaction *trans)
1810 wait_event(fs_info->transaction_wait,
1811 trans->state >= TRANS_STATE_UNBLOCKED ||
1812 TRANS_ABORTED(trans));
1816 * commit transactions asynchronously. once btrfs_commit_transaction_async
1817 * returns, any subsequent transaction will not be allowed to join.
1819 struct btrfs_async_commit {
1820 struct btrfs_trans_handle *newtrans;
1821 struct work_struct work;
1824 static void do_async_commit(struct work_struct *work)
1826 struct btrfs_async_commit *ac =
1827 container_of(work, struct btrfs_async_commit, work);
1830 * We've got freeze protection passed with the transaction.
1831 * Tell lockdep about it.
1833 if (ac->newtrans->type & __TRANS_FREEZABLE)
1834 __sb_writers_acquired(ac->newtrans->fs_info->sb, SB_FREEZE_FS);
1836 current->journal_info = ac->newtrans;
1838 btrfs_commit_transaction(ac->newtrans);
1842 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
1843 int wait_for_unblock)
1845 struct btrfs_fs_info *fs_info = trans->fs_info;
1846 struct btrfs_async_commit *ac;
1847 struct btrfs_transaction *cur_trans;
1849 ac = kmalloc(sizeof(*ac), GFP_NOFS);
1853 INIT_WORK(&ac->work, do_async_commit);
1854 ac->newtrans = btrfs_join_transaction(trans->root);
1855 if (IS_ERR(ac->newtrans)) {
1856 int err = PTR_ERR(ac->newtrans);
1861 /* take transaction reference */
1862 cur_trans = trans->transaction;
1863 refcount_inc(&cur_trans->use_count);
1865 btrfs_end_transaction(trans);
1868 * Tell lockdep we've released the freeze rwsem, since the
1869 * async commit thread will be the one to unlock it.
1871 if (ac->newtrans->type & __TRANS_FREEZABLE)
1872 __sb_writers_release(fs_info->sb, SB_FREEZE_FS);
1874 schedule_work(&ac->work);
1876 /* wait for transaction to start and unblock */
1877 if (wait_for_unblock)
1878 wait_current_trans_commit_start_and_unblock(fs_info, cur_trans);
1880 wait_current_trans_commit_start(fs_info, cur_trans);
1882 if (current->journal_info == trans)
1883 current->journal_info = NULL;
1885 btrfs_put_transaction(cur_trans);
1890 static void cleanup_transaction(struct btrfs_trans_handle *trans, int err)
1892 struct btrfs_fs_info *fs_info = trans->fs_info;
1893 struct btrfs_transaction *cur_trans = trans->transaction;
1895 WARN_ON(refcount_read(&trans->use_count) > 1);
1897 btrfs_abort_transaction(trans, err);
1899 spin_lock(&fs_info->trans_lock);
1902 * If the transaction is removed from the list, it means this
1903 * transaction has been committed successfully, so it is impossible
1904 * to call the cleanup function.
1906 BUG_ON(list_empty(&cur_trans->list));
1908 list_del_init(&cur_trans->list);
1909 if (cur_trans == fs_info->running_transaction) {
1910 cur_trans->state = TRANS_STATE_COMMIT_DOING;
1911 spin_unlock(&fs_info->trans_lock);
1912 wait_event(cur_trans->writer_wait,
1913 atomic_read(&cur_trans->num_writers) == 1);
1915 spin_lock(&fs_info->trans_lock);
1917 spin_unlock(&fs_info->trans_lock);
1919 btrfs_cleanup_one_transaction(trans->transaction, fs_info);
1921 spin_lock(&fs_info->trans_lock);
1922 if (cur_trans == fs_info->running_transaction)
1923 fs_info->running_transaction = NULL;
1924 spin_unlock(&fs_info->trans_lock);
1926 if (trans->type & __TRANS_FREEZABLE)
1927 sb_end_intwrite(fs_info->sb);
1928 btrfs_put_transaction(cur_trans);
1929 btrfs_put_transaction(cur_trans);
1931 trace_btrfs_transaction_commit(trans->root);
1933 if (current->journal_info == trans)
1934 current->journal_info = NULL;
1935 btrfs_scrub_cancel(fs_info);
1937 kmem_cache_free(btrfs_trans_handle_cachep, trans);
1941 * Release reserved delayed ref space of all pending block groups of the
1942 * transaction and remove them from the list
1944 static void btrfs_cleanup_pending_block_groups(struct btrfs_trans_handle *trans)
1946 struct btrfs_fs_info *fs_info = trans->fs_info;
1947 struct btrfs_block_group *block_group, *tmp;
1949 list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
1950 btrfs_delayed_refs_rsv_release(fs_info, 1);
1951 list_del_init(&block_group->bg_list);
1955 static inline int btrfs_start_delalloc_flush(struct btrfs_trans_handle *trans)
1957 struct btrfs_fs_info *fs_info = trans->fs_info;
1960 * We use writeback_inodes_sb here because if we used
1961 * btrfs_start_delalloc_roots we would deadlock with fs freeze.
1962 * Currently are holding the fs freeze lock, if we do an async flush
1963 * we'll do btrfs_join_transaction() and deadlock because we need to
1964 * wait for the fs freeze lock. Using the direct flushing we benefit
1965 * from already being in a transaction and our join_transaction doesn't
1966 * have to re-take the fs freeze lock.
1968 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) {
1969 writeback_inodes_sb(fs_info->sb, WB_REASON_SYNC);
1971 struct btrfs_pending_snapshot *pending;
1972 struct list_head *head = &trans->transaction->pending_snapshots;
1975 * Flush dellaloc for any root that is going to be snapshotted.
1976 * This is done to avoid a corrupted version of files, in the
1977 * snapshots, that had both buffered and direct IO writes (even
1978 * if they were done sequentially) due to an unordered update of
1979 * the inode's size on disk.
1981 list_for_each_entry(pending, head, list) {
1984 ret = btrfs_start_delalloc_snapshot(pending->root);
1992 static inline void btrfs_wait_delalloc_flush(struct btrfs_trans_handle *trans)
1994 struct btrfs_fs_info *fs_info = trans->fs_info;
1996 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) {
1997 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
1999 struct btrfs_pending_snapshot *pending;
2000 struct list_head *head = &trans->transaction->pending_snapshots;
2003 * Wait for any dellaloc that we started previously for the roots
2004 * that are going to be snapshotted. This is to avoid a corrupted
2005 * version of files in the snapshots that had both buffered and
2006 * direct IO writes (even if they were done sequentially).
2008 list_for_each_entry(pending, head, list)
2009 btrfs_wait_ordered_extents(pending->root,
2010 U64_MAX, 0, U64_MAX);
2014 int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
2016 struct btrfs_fs_info *fs_info = trans->fs_info;
2017 struct btrfs_transaction *cur_trans = trans->transaction;
2018 struct btrfs_transaction *prev_trans = NULL;
2021 ASSERT(refcount_read(&trans->use_count) == 1);
2024 * Some places just start a transaction to commit it. We need to make
2025 * sure that if this commit fails that the abort code actually marks the
2026 * transaction as failed, so set trans->dirty to make the abort code do
2029 trans->dirty = true;
2031 /* Stop the commit early if ->aborted is set */
2032 if (TRANS_ABORTED(cur_trans)) {
2033 ret = cur_trans->aborted;
2034 btrfs_end_transaction(trans);
2038 btrfs_trans_release_metadata(trans);
2039 trans->block_rsv = NULL;
2041 /* make a pass through all the delayed refs we have so far
2042 * any runnings procs may add more while we are here
2044 ret = btrfs_run_delayed_refs(trans, 0);
2046 btrfs_end_transaction(trans);
2050 cur_trans = trans->transaction;
2053 * set the flushing flag so procs in this transaction have to
2054 * start sending their work down.
2056 cur_trans->delayed_refs.flushing = 1;
2059 btrfs_create_pending_block_groups(trans);
2061 ret = btrfs_run_delayed_refs(trans, 0);
2063 btrfs_end_transaction(trans);
2067 if (!test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &cur_trans->flags)) {
2070 /* this mutex is also taken before trying to set
2071 * block groups readonly. We need to make sure
2072 * that nobody has set a block group readonly
2073 * after a extents from that block group have been
2074 * allocated for cache files. btrfs_set_block_group_ro
2075 * will wait for the transaction to commit if it
2076 * finds BTRFS_TRANS_DIRTY_BG_RUN set.
2078 * The BTRFS_TRANS_DIRTY_BG_RUN flag is also used to make sure
2079 * only one process starts all the block group IO. It wouldn't
2080 * hurt to have more than one go through, but there's no
2081 * real advantage to it either.
2083 mutex_lock(&fs_info->ro_block_group_mutex);
2084 if (!test_and_set_bit(BTRFS_TRANS_DIRTY_BG_RUN,
2087 mutex_unlock(&fs_info->ro_block_group_mutex);
2090 ret = btrfs_start_dirty_block_groups(trans);
2092 btrfs_end_transaction(trans);
2098 spin_lock(&fs_info->trans_lock);
2099 if (cur_trans->state >= TRANS_STATE_COMMIT_START) {
2100 spin_unlock(&fs_info->trans_lock);
2101 refcount_inc(&cur_trans->use_count);
2102 ret = btrfs_end_transaction(trans);
2104 wait_for_commit(cur_trans);
2106 if (TRANS_ABORTED(cur_trans))
2107 ret = cur_trans->aborted;
2109 btrfs_put_transaction(cur_trans);
2114 cur_trans->state = TRANS_STATE_COMMIT_START;
2115 wake_up(&fs_info->transaction_blocked_wait);
2117 if (cur_trans->list.prev != &fs_info->trans_list) {
2118 prev_trans = list_entry(cur_trans->list.prev,
2119 struct btrfs_transaction, list);
2120 if (prev_trans->state != TRANS_STATE_COMPLETED) {
2121 refcount_inc(&prev_trans->use_count);
2122 spin_unlock(&fs_info->trans_lock);
2124 wait_for_commit(prev_trans);
2125 ret = READ_ONCE(prev_trans->aborted);
2127 btrfs_put_transaction(prev_trans);
2129 goto cleanup_transaction;
2131 spin_unlock(&fs_info->trans_lock);
2134 spin_unlock(&fs_info->trans_lock);
2136 * The previous transaction was aborted and was already removed
2137 * from the list of transactions at fs_info->trans_list. So we
2138 * abort to prevent writing a new superblock that reflects a
2139 * corrupt state (pointing to trees with unwritten nodes/leafs).
2141 if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state)) {
2143 goto cleanup_transaction;
2147 extwriter_counter_dec(cur_trans, trans->type);
2149 ret = btrfs_start_delalloc_flush(trans);
2151 goto cleanup_transaction;
2153 ret = btrfs_run_delayed_items(trans);
2155 goto cleanup_transaction;
2157 wait_event(cur_trans->writer_wait,
2158 extwriter_counter_read(cur_trans) == 0);
2160 /* some pending stuffs might be added after the previous flush. */
2161 ret = btrfs_run_delayed_items(trans);
2163 goto cleanup_transaction;
2165 btrfs_wait_delalloc_flush(trans);
2167 btrfs_scrub_pause(fs_info);
2169 * Ok now we need to make sure to block out any other joins while we
2170 * commit the transaction. We could have started a join before setting
2171 * COMMIT_DOING so make sure to wait for num_writers to == 1 again.
2173 spin_lock(&fs_info->trans_lock);
2174 cur_trans->state = TRANS_STATE_COMMIT_DOING;
2175 spin_unlock(&fs_info->trans_lock);
2176 wait_event(cur_trans->writer_wait,
2177 atomic_read(&cur_trans->num_writers) == 1);
2179 if (TRANS_ABORTED(cur_trans)) {
2180 ret = cur_trans->aborted;
2181 goto scrub_continue;
2184 * the reloc mutex makes sure that we stop
2185 * the balancing code from coming in and moving
2186 * extents around in the middle of the commit
2188 mutex_lock(&fs_info->reloc_mutex);
2191 * We needn't worry about the delayed items because we will
2192 * deal with them in create_pending_snapshot(), which is the
2193 * core function of the snapshot creation.
2195 ret = create_pending_snapshots(trans);
2200 * We insert the dir indexes of the snapshots and update the inode
2201 * of the snapshots' parents after the snapshot creation, so there
2202 * are some delayed items which are not dealt with. Now deal with
2205 * We needn't worry that this operation will corrupt the snapshots,
2206 * because all the tree which are snapshoted will be forced to COW
2207 * the nodes and leaves.
2209 ret = btrfs_run_delayed_items(trans);
2213 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
2218 * make sure none of the code above managed to slip in a
2221 btrfs_assert_delayed_root_empty(fs_info);
2223 WARN_ON(cur_trans != trans->transaction);
2225 /* btrfs_commit_tree_roots is responsible for getting the
2226 * various roots consistent with each other. Every pointer
2227 * in the tree of tree roots has to point to the most up to date
2228 * root for every subvolume and other tree. So, we have to keep
2229 * the tree logging code from jumping in and changing any
2232 * At this point in the commit, there can't be any tree-log
2233 * writers, but a little lower down we drop the trans mutex
2234 * and let new people in. By holding the tree_log_mutex
2235 * from now until after the super is written, we avoid races
2236 * with the tree-log code.
2238 mutex_lock(&fs_info->tree_log_mutex);
2240 ret = commit_fs_roots(trans);
2242 goto unlock_tree_log;
2245 * Since the transaction is done, we can apply the pending changes
2246 * before the next transaction.
2248 btrfs_apply_pending_changes(fs_info);
2250 /* commit_fs_roots gets rid of all the tree log roots, it is now
2251 * safe to free the root of tree log roots
2253 btrfs_free_log_root_tree(trans, fs_info);
2256 * commit_fs_roots() can call btrfs_save_ino_cache(), which generates
2257 * new delayed refs. Must handle them or qgroup can be wrong.
2259 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
2261 goto unlock_tree_log;
2264 * Since fs roots are all committed, we can get a quite accurate
2265 * new_roots. So let's do quota accounting.
2267 ret = btrfs_qgroup_account_extents(trans);
2269 goto unlock_tree_log;
2271 ret = commit_cowonly_roots(trans);
2273 goto unlock_tree_log;
2276 * The tasks which save the space cache and inode cache may also
2277 * update ->aborted, check it.
2279 if (TRANS_ABORTED(cur_trans)) {
2280 ret = cur_trans->aborted;
2281 goto unlock_tree_log;
2284 btrfs_prepare_extent_commit(fs_info);
2286 cur_trans = fs_info->running_transaction;
2288 btrfs_set_root_node(&fs_info->tree_root->root_item,
2289 fs_info->tree_root->node);
2290 list_add_tail(&fs_info->tree_root->dirty_list,
2291 &cur_trans->switch_commits);
2293 btrfs_set_root_node(&fs_info->chunk_root->root_item,
2294 fs_info->chunk_root->node);
2295 list_add_tail(&fs_info->chunk_root->dirty_list,
2296 &cur_trans->switch_commits);
2298 switch_commit_roots(trans);
2300 ASSERT(list_empty(&cur_trans->dirty_bgs));
2301 ASSERT(list_empty(&cur_trans->io_bgs));
2302 update_super_roots(fs_info);
2304 btrfs_set_super_log_root(fs_info->super_copy, 0);
2305 btrfs_set_super_log_root_level(fs_info->super_copy, 0);
2306 memcpy(fs_info->super_for_commit, fs_info->super_copy,
2307 sizeof(*fs_info->super_copy));
2309 btrfs_commit_device_sizes(cur_trans);
2311 clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags);
2312 clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags);
2314 btrfs_trans_release_chunk_metadata(trans);
2316 spin_lock(&fs_info->trans_lock);
2317 cur_trans->state = TRANS_STATE_UNBLOCKED;
2318 fs_info->running_transaction = NULL;
2319 spin_unlock(&fs_info->trans_lock);
2320 mutex_unlock(&fs_info->reloc_mutex);
2322 wake_up(&fs_info->transaction_wait);
2324 ret = btrfs_write_and_wait_transaction(trans);
2326 btrfs_handle_fs_error(fs_info, ret,
2327 "Error while writing out transaction");
2329 * reloc_mutex has been unlocked, tree_log_mutex is still held
2330 * but we can't jump to unlock_tree_log causing double unlock
2332 mutex_unlock(&fs_info->tree_log_mutex);
2333 goto scrub_continue;
2336 ret = write_all_supers(fs_info, 0);
2338 * the super is written, we can safely allow the tree-loggers
2339 * to go about their business
2341 mutex_unlock(&fs_info->tree_log_mutex);
2343 goto scrub_continue;
2345 btrfs_finish_extent_commit(trans);
2347 if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &cur_trans->flags))
2348 btrfs_clear_space_info_full(fs_info);
2350 fs_info->last_trans_committed = cur_trans->transid;
2352 * We needn't acquire the lock here because there is no other task
2353 * which can change it.
2355 cur_trans->state = TRANS_STATE_COMPLETED;
2356 wake_up(&cur_trans->commit_wait);
2358 spin_lock(&fs_info->trans_lock);
2359 list_del_init(&cur_trans->list);
2360 spin_unlock(&fs_info->trans_lock);
2362 btrfs_put_transaction(cur_trans);
2363 btrfs_put_transaction(cur_trans);
2365 if (trans->type & __TRANS_FREEZABLE)
2366 sb_end_intwrite(fs_info->sb);
2368 trace_btrfs_transaction_commit(trans->root);
2370 btrfs_scrub_continue(fs_info);
2372 if (current->journal_info == trans)
2373 current->journal_info = NULL;
2375 kmem_cache_free(btrfs_trans_handle_cachep, trans);
2380 mutex_unlock(&fs_info->tree_log_mutex);
2382 mutex_unlock(&fs_info->reloc_mutex);
2384 btrfs_scrub_continue(fs_info);
2385 cleanup_transaction:
2386 btrfs_trans_release_metadata(trans);
2387 btrfs_cleanup_pending_block_groups(trans);
2388 btrfs_trans_release_chunk_metadata(trans);
2389 trans->block_rsv = NULL;
2390 btrfs_warn(fs_info, "Skipping commit of aborted transaction.");
2391 if (current->journal_info == trans)
2392 current->journal_info = NULL;
2393 cleanup_transaction(trans, ret);
2399 * return < 0 if error
2400 * 0 if there are no more dead_roots at the time of call
2401 * 1 there are more to be processed, call me again
2403 * The return value indicates there are certainly more snapshots to delete, but
2404 * if there comes a new one during processing, it may return 0. We don't mind,
2405 * because btrfs_commit_super will poke cleaner thread and it will process it a
2406 * few seconds later.
2408 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root)
2411 struct btrfs_fs_info *fs_info = root->fs_info;
2413 spin_lock(&fs_info->trans_lock);
2414 if (list_empty(&fs_info->dead_roots)) {
2415 spin_unlock(&fs_info->trans_lock);
2418 root = list_first_entry(&fs_info->dead_roots,
2419 struct btrfs_root, root_list);
2420 list_del_init(&root->root_list);
2421 spin_unlock(&fs_info->trans_lock);
2423 btrfs_debug(fs_info, "cleaner removing %llu", root->root_key.objectid);
2425 btrfs_kill_all_delayed_nodes(root);
2426 if (root->ino_cache_inode) {
2427 iput(root->ino_cache_inode);
2428 root->ino_cache_inode = NULL;
2431 if (btrfs_header_backref_rev(root->node) <
2432 BTRFS_MIXED_BACKREF_REV)
2433 ret = btrfs_drop_snapshot(root, 0, 0);
2435 ret = btrfs_drop_snapshot(root, 1, 0);
2437 btrfs_put_root(root);
2438 return (ret < 0) ? 0 : 1;
2441 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info)
2446 prev = xchg(&fs_info->pending_changes, 0);
2450 bit = 1 << BTRFS_PENDING_SET_INODE_MAP_CACHE;
2452 btrfs_set_opt(fs_info->mount_opt, INODE_MAP_CACHE);
2455 bit = 1 << BTRFS_PENDING_CLEAR_INODE_MAP_CACHE;
2457 btrfs_clear_opt(fs_info->mount_opt, INODE_MAP_CACHE);
2460 bit = 1 << BTRFS_PENDING_COMMIT;
2462 btrfs_debug(fs_info, "pending commit done");
2467 "unknown pending changes left 0x%lx, ignoring", prev);