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"
25 #define BTRFS_ROOT_TRANS_TAG 0
28 * Transaction states and transitions
30 * No running transaction (fs tree blocks are not modified)
33 * | Call start_transaction() variants. Except btrfs_join_transaction_nostart().
35 * Transaction N [[TRANS_STATE_RUNNING]]
37 * | New trans handles can be attached to transaction N by calling all
38 * | start_transaction() variants.
41 * | Call btrfs_commit_transaction() on any trans handle attached to
44 * Transaction N [[TRANS_STATE_COMMIT_START]]
46 * | Will wait for previous running transaction to completely finish if there
49 * | Then one of the following happes:
50 * | - Wait for all other trans handle holders to release.
51 * | The btrfs_commit_transaction() caller will do the commit work.
52 * | - Wait for current transaction to be committed by others.
53 * | Other btrfs_commit_transaction() caller will do the commit work.
55 * | At this stage, only btrfs_join_transaction*() variants can attach
56 * | to this running transaction.
57 * | All other variants will wait for current one to finish and attach to
61 * | Caller is chosen to commit transaction N, and all other trans handle
62 * | haven been released.
64 * Transaction N [[TRANS_STATE_COMMIT_DOING]]
66 * | The heavy lifting transaction work is started.
67 * | From running delayed refs (modifying extent tree) to creating pending
68 * | snapshots, running qgroups.
69 * | In short, modify supporting trees to reflect modifications of subvolume
72 * | At this stage, all start_transaction() calls will wait for this
73 * | transaction to finish and attach to transaction N+1.
76 * | Until all supporting trees are updated.
78 * Transaction N [[TRANS_STATE_UNBLOCKED]]
80 * | All needed trees are modified, thus we only [[TRANS_STATE_RUNNING]]
81 * | need to write them back to disk and update |
84 * | At this stage, new transaction is allowed to |
86 * | All new start_transaction() calls will be |
87 * | attached to transid N+1. |
90 * | Until all tree blocks are super blocks are |
91 * | written to block devices |
93 * Transaction N [[TRANS_STATE_COMPLETED]] V
94 * All tree blocks and super blocks are written. Transaction N+1
95 * This transaction is finished and all its [[TRANS_STATE_COMMIT_START]]
96 * data structures will be cleaned up. | Life goes on
98 static const unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = {
99 [TRANS_STATE_RUNNING] = 0U,
100 [TRANS_STATE_COMMIT_START] = (__TRANS_START | __TRANS_ATTACH),
101 [TRANS_STATE_COMMIT_DOING] = (__TRANS_START |
104 __TRANS_JOIN_NOSTART),
105 [TRANS_STATE_UNBLOCKED] = (__TRANS_START |
108 __TRANS_JOIN_NOLOCK |
109 __TRANS_JOIN_NOSTART),
110 [TRANS_STATE_COMPLETED] = (__TRANS_START |
113 __TRANS_JOIN_NOLOCK |
114 __TRANS_JOIN_NOSTART),
117 void btrfs_put_transaction(struct btrfs_transaction *transaction)
119 WARN_ON(refcount_read(&transaction->use_count) == 0);
120 if (refcount_dec_and_test(&transaction->use_count)) {
121 BUG_ON(!list_empty(&transaction->list));
122 WARN_ON(!RB_EMPTY_ROOT(
123 &transaction->delayed_refs.href_root.rb_root));
124 if (transaction->delayed_refs.pending_csums)
125 btrfs_err(transaction->fs_info,
126 "pending csums is %llu",
127 transaction->delayed_refs.pending_csums);
129 * If any block groups are found in ->deleted_bgs then it's
130 * because the transaction was aborted and a commit did not
131 * happen (things failed before writing the new superblock
132 * and calling btrfs_finish_extent_commit()), so we can not
133 * discard the physical locations of the block groups.
135 while (!list_empty(&transaction->deleted_bgs)) {
136 struct btrfs_block_group *cache;
138 cache = list_first_entry(&transaction->deleted_bgs,
139 struct btrfs_block_group,
141 list_del_init(&cache->bg_list);
142 btrfs_put_block_group_trimming(cache);
143 btrfs_put_block_group(cache);
145 WARN_ON(!list_empty(&transaction->dev_update_list));
150 static noinline void switch_commit_roots(struct btrfs_transaction *trans)
152 struct btrfs_fs_info *fs_info = trans->fs_info;
153 struct btrfs_root *root, *tmp;
155 down_write(&fs_info->commit_root_sem);
156 list_for_each_entry_safe(root, tmp, &trans->switch_commits,
158 list_del_init(&root->dirty_list);
159 free_extent_buffer(root->commit_root);
160 root->commit_root = btrfs_root_node(root);
161 if (is_fstree(root->root_key.objectid))
162 btrfs_unpin_free_ino(root);
163 extent_io_tree_release(&root->dirty_log_pages);
164 btrfs_qgroup_clean_swapped_blocks(root);
167 /* We can free old roots now. */
168 spin_lock(&trans->dropped_roots_lock);
169 while (!list_empty(&trans->dropped_roots)) {
170 root = list_first_entry(&trans->dropped_roots,
171 struct btrfs_root, root_list);
172 list_del_init(&root->root_list);
173 spin_unlock(&trans->dropped_roots_lock);
174 btrfs_drop_and_free_fs_root(fs_info, root);
175 spin_lock(&trans->dropped_roots_lock);
177 spin_unlock(&trans->dropped_roots_lock);
178 up_write(&fs_info->commit_root_sem);
181 static inline void extwriter_counter_inc(struct btrfs_transaction *trans,
184 if (type & TRANS_EXTWRITERS)
185 atomic_inc(&trans->num_extwriters);
188 static inline void extwriter_counter_dec(struct btrfs_transaction *trans,
191 if (type & TRANS_EXTWRITERS)
192 atomic_dec(&trans->num_extwriters);
195 static inline void extwriter_counter_init(struct btrfs_transaction *trans,
198 atomic_set(&trans->num_extwriters, ((type & TRANS_EXTWRITERS) ? 1 : 0));
201 static inline int extwriter_counter_read(struct btrfs_transaction *trans)
203 return atomic_read(&trans->num_extwriters);
207 * To be called after all the new block groups attached to the transaction
208 * handle have been created (btrfs_create_pending_block_groups()).
210 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
212 struct btrfs_fs_info *fs_info = trans->fs_info;
214 if (!trans->chunk_bytes_reserved)
217 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
219 btrfs_block_rsv_release(fs_info, &fs_info->chunk_block_rsv,
220 trans->chunk_bytes_reserved);
221 trans->chunk_bytes_reserved = 0;
225 * either allocate a new transaction or hop into the existing one
227 static noinline int join_transaction(struct btrfs_fs_info *fs_info,
230 struct btrfs_transaction *cur_trans;
232 spin_lock(&fs_info->trans_lock);
234 /* The file system has been taken offline. No new transactions. */
235 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
236 spin_unlock(&fs_info->trans_lock);
240 cur_trans = fs_info->running_transaction;
242 if (cur_trans->aborted) {
243 spin_unlock(&fs_info->trans_lock);
244 return cur_trans->aborted;
246 if (btrfs_blocked_trans_types[cur_trans->state] & type) {
247 spin_unlock(&fs_info->trans_lock);
250 refcount_inc(&cur_trans->use_count);
251 atomic_inc(&cur_trans->num_writers);
252 extwriter_counter_inc(cur_trans, type);
253 spin_unlock(&fs_info->trans_lock);
256 spin_unlock(&fs_info->trans_lock);
259 * If we are ATTACH, we just want to catch the current transaction,
260 * and commit it. If there is no transaction, just return ENOENT.
262 if (type == TRANS_ATTACH)
266 * JOIN_NOLOCK only happens during the transaction commit, so
267 * it is impossible that ->running_transaction is NULL
269 BUG_ON(type == TRANS_JOIN_NOLOCK);
271 cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS);
275 spin_lock(&fs_info->trans_lock);
276 if (fs_info->running_transaction) {
278 * someone started a transaction after we unlocked. Make sure
279 * to redo the checks above
283 } else if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
284 spin_unlock(&fs_info->trans_lock);
289 cur_trans->fs_info = fs_info;
290 atomic_set(&cur_trans->num_writers, 1);
291 extwriter_counter_init(cur_trans, type);
292 init_waitqueue_head(&cur_trans->writer_wait);
293 init_waitqueue_head(&cur_trans->commit_wait);
294 cur_trans->state = TRANS_STATE_RUNNING;
296 * One for this trans handle, one so it will live on until we
297 * commit the transaction.
299 refcount_set(&cur_trans->use_count, 2);
300 cur_trans->flags = 0;
301 cur_trans->start_time = ktime_get_seconds();
303 memset(&cur_trans->delayed_refs, 0, sizeof(cur_trans->delayed_refs));
305 cur_trans->delayed_refs.href_root = RB_ROOT_CACHED;
306 cur_trans->delayed_refs.dirty_extent_root = RB_ROOT;
307 atomic_set(&cur_trans->delayed_refs.num_entries, 0);
310 * although the tree mod log is per file system and not per transaction,
311 * the log must never go across transaction boundaries.
314 if (!list_empty(&fs_info->tree_mod_seq_list))
315 WARN(1, KERN_ERR "BTRFS: tree_mod_seq_list not empty when creating a fresh transaction\n");
316 if (!RB_EMPTY_ROOT(&fs_info->tree_mod_log))
317 WARN(1, KERN_ERR "BTRFS: tree_mod_log rb tree not empty when creating a fresh transaction\n");
318 atomic64_set(&fs_info->tree_mod_seq, 0);
320 spin_lock_init(&cur_trans->delayed_refs.lock);
322 INIT_LIST_HEAD(&cur_trans->pending_snapshots);
323 INIT_LIST_HEAD(&cur_trans->dev_update_list);
324 INIT_LIST_HEAD(&cur_trans->switch_commits);
325 INIT_LIST_HEAD(&cur_trans->dirty_bgs);
326 INIT_LIST_HEAD(&cur_trans->io_bgs);
327 INIT_LIST_HEAD(&cur_trans->dropped_roots);
328 mutex_init(&cur_trans->cache_write_mutex);
329 spin_lock_init(&cur_trans->dirty_bgs_lock);
330 INIT_LIST_HEAD(&cur_trans->deleted_bgs);
331 spin_lock_init(&cur_trans->dropped_roots_lock);
332 list_add_tail(&cur_trans->list, &fs_info->trans_list);
333 extent_io_tree_init(fs_info, &cur_trans->dirty_pages,
334 IO_TREE_TRANS_DIRTY_PAGES, fs_info->btree_inode);
335 fs_info->generation++;
336 cur_trans->transid = fs_info->generation;
337 fs_info->running_transaction = cur_trans;
338 cur_trans->aborted = 0;
339 spin_unlock(&fs_info->trans_lock);
345 * this does all the record keeping required to make sure that a reference
346 * counted root is properly recorded in a given transaction. This is required
347 * to make sure the old root from before we joined the transaction is deleted
348 * when the transaction commits
350 static int record_root_in_trans(struct btrfs_trans_handle *trans,
351 struct btrfs_root *root,
354 struct btrfs_fs_info *fs_info = root->fs_info;
356 if ((test_bit(BTRFS_ROOT_REF_COWS, &root->state) &&
357 root->last_trans < trans->transid) || force) {
358 WARN_ON(root == fs_info->extent_root);
359 WARN_ON(!force && root->commit_root != root->node);
362 * see below for IN_TRANS_SETUP usage rules
363 * we have the reloc mutex held now, so there
364 * is only one writer in this function
366 set_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
368 /* make sure readers find IN_TRANS_SETUP before
369 * they find our root->last_trans update
373 spin_lock(&fs_info->fs_roots_radix_lock);
374 if (root->last_trans == trans->transid && !force) {
375 spin_unlock(&fs_info->fs_roots_radix_lock);
378 radix_tree_tag_set(&fs_info->fs_roots_radix,
379 (unsigned long)root->root_key.objectid,
380 BTRFS_ROOT_TRANS_TAG);
381 spin_unlock(&fs_info->fs_roots_radix_lock);
382 root->last_trans = trans->transid;
384 /* this is pretty tricky. We don't want to
385 * take the relocation lock in btrfs_record_root_in_trans
386 * unless we're really doing the first setup for this root in
389 * Normally we'd use root->last_trans as a flag to decide
390 * if we want to take the expensive mutex.
392 * But, we have to set root->last_trans before we
393 * init the relocation root, otherwise, we trip over warnings
394 * in ctree.c. The solution used here is to flag ourselves
395 * with root IN_TRANS_SETUP. When this is 1, we're still
396 * fixing up the reloc trees and everyone must wait.
398 * When this is zero, they can trust root->last_trans and fly
399 * through btrfs_record_root_in_trans without having to take the
400 * lock. smp_wmb() makes sure that all the writes above are
401 * done before we pop in the zero below
403 btrfs_init_reloc_root(trans, root);
404 smp_mb__before_atomic();
405 clear_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
411 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
412 struct btrfs_root *root)
414 struct btrfs_fs_info *fs_info = root->fs_info;
415 struct btrfs_transaction *cur_trans = trans->transaction;
417 /* Add ourselves to the transaction dropped list */
418 spin_lock(&cur_trans->dropped_roots_lock);
419 list_add_tail(&root->root_list, &cur_trans->dropped_roots);
420 spin_unlock(&cur_trans->dropped_roots_lock);
422 /* Make sure we don't try to update the root at commit time */
423 spin_lock(&fs_info->fs_roots_radix_lock);
424 radix_tree_tag_clear(&fs_info->fs_roots_radix,
425 (unsigned long)root->root_key.objectid,
426 BTRFS_ROOT_TRANS_TAG);
427 spin_unlock(&fs_info->fs_roots_radix_lock);
430 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
431 struct btrfs_root *root)
433 struct btrfs_fs_info *fs_info = root->fs_info;
435 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
439 * see record_root_in_trans for comments about IN_TRANS_SETUP usage
443 if (root->last_trans == trans->transid &&
444 !test_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state))
447 mutex_lock(&fs_info->reloc_mutex);
448 record_root_in_trans(trans, root, 0);
449 mutex_unlock(&fs_info->reloc_mutex);
454 static inline int is_transaction_blocked(struct btrfs_transaction *trans)
456 return (trans->state >= TRANS_STATE_COMMIT_START &&
457 trans->state < TRANS_STATE_UNBLOCKED &&
461 /* wait for commit against the current transaction to become unblocked
462 * when this is done, it is safe to start a new transaction, but the current
463 * transaction might not be fully on disk.
465 static void wait_current_trans(struct btrfs_fs_info *fs_info)
467 struct btrfs_transaction *cur_trans;
469 spin_lock(&fs_info->trans_lock);
470 cur_trans = fs_info->running_transaction;
471 if (cur_trans && is_transaction_blocked(cur_trans)) {
472 refcount_inc(&cur_trans->use_count);
473 spin_unlock(&fs_info->trans_lock);
475 wait_event(fs_info->transaction_wait,
476 cur_trans->state >= TRANS_STATE_UNBLOCKED ||
478 btrfs_put_transaction(cur_trans);
480 spin_unlock(&fs_info->trans_lock);
484 static int may_wait_transaction(struct btrfs_fs_info *fs_info, int type)
486 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
489 if (type == TRANS_START)
495 static inline bool need_reserve_reloc_root(struct btrfs_root *root)
497 struct btrfs_fs_info *fs_info = root->fs_info;
499 if (!fs_info->reloc_ctl ||
500 !test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
501 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
508 static struct btrfs_trans_handle *
509 start_transaction(struct btrfs_root *root, unsigned int num_items,
510 unsigned int type, enum btrfs_reserve_flush_enum flush,
511 bool enforce_qgroups)
513 struct btrfs_fs_info *fs_info = root->fs_info;
514 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
515 struct btrfs_trans_handle *h;
516 struct btrfs_transaction *cur_trans;
518 u64 qgroup_reserved = 0;
519 bool reloc_reserved = false;
522 /* Send isn't supposed to start transactions. */
523 ASSERT(current->journal_info != BTRFS_SEND_TRANS_STUB);
525 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
526 return ERR_PTR(-EROFS);
528 if (current->journal_info) {
529 WARN_ON(type & TRANS_EXTWRITERS);
530 h = current->journal_info;
531 refcount_inc(&h->use_count);
532 WARN_ON(refcount_read(&h->use_count) > 2);
533 h->orig_rsv = h->block_rsv;
539 * Do the reservation before we join the transaction so we can do all
540 * the appropriate flushing if need be.
542 if (num_items && root != fs_info->chunk_root) {
543 struct btrfs_block_rsv *rsv = &fs_info->trans_block_rsv;
544 u64 delayed_refs_bytes = 0;
546 qgroup_reserved = num_items * fs_info->nodesize;
547 ret = btrfs_qgroup_reserve_meta_pertrans(root, qgroup_reserved,
553 * We want to reserve all the bytes we may need all at once, so
554 * we only do 1 enospc flushing cycle per transaction start. We
555 * accomplish this by simply assuming we'll do 2 x num_items
556 * worth of delayed refs updates in this trans handle, and
557 * refill that amount for whatever is missing in the reserve.
559 num_bytes = btrfs_calc_insert_metadata_size(fs_info, num_items);
560 if (delayed_refs_rsv->full == 0) {
561 delayed_refs_bytes = num_bytes;
566 * Do the reservation for the relocation root creation
568 if (need_reserve_reloc_root(root)) {
569 num_bytes += fs_info->nodesize;
570 reloc_reserved = true;
573 ret = btrfs_block_rsv_add(root, rsv, num_bytes, flush);
576 if (delayed_refs_bytes) {
577 btrfs_migrate_to_delayed_refs_rsv(fs_info, rsv,
579 num_bytes -= delayed_refs_bytes;
581 } else if (num_items == 0 && flush == BTRFS_RESERVE_FLUSH_ALL &&
582 !delayed_refs_rsv->full) {
584 * Some people call with btrfs_start_transaction(root, 0)
585 * because they can be throttled, but have some other mechanism
586 * for reserving space. We still want these guys to refill the
587 * delayed block_rsv so just add 1 items worth of reservation
590 ret = btrfs_delayed_refs_rsv_refill(fs_info, flush);
595 h = kmem_cache_zalloc(btrfs_trans_handle_cachep, GFP_NOFS);
602 * If we are JOIN_NOLOCK we're already committing a transaction and
603 * waiting on this guy, so we don't need to do the sb_start_intwrite
604 * because we're already holding a ref. We need this because we could
605 * have raced in and did an fsync() on a file which can kick a commit
606 * and then we deadlock with somebody doing a freeze.
608 * If we are ATTACH, it means we just want to catch the current
609 * transaction and commit it, so we needn't do sb_start_intwrite().
611 if (type & __TRANS_FREEZABLE)
612 sb_start_intwrite(fs_info->sb);
614 if (may_wait_transaction(fs_info, type))
615 wait_current_trans(fs_info);
618 ret = join_transaction(fs_info, type);
620 wait_current_trans(fs_info);
621 if (unlikely(type == TRANS_ATTACH ||
622 type == TRANS_JOIN_NOSTART))
625 } while (ret == -EBUSY);
630 cur_trans = fs_info->running_transaction;
632 h->transid = cur_trans->transid;
633 h->transaction = cur_trans;
635 refcount_set(&h->use_count, 1);
636 h->fs_info = root->fs_info;
639 h->can_flush_pending_bgs = true;
640 INIT_LIST_HEAD(&h->new_bgs);
643 if (cur_trans->state >= TRANS_STATE_COMMIT_START &&
644 may_wait_transaction(fs_info, type)) {
645 current->journal_info = h;
646 btrfs_commit_transaction(h);
651 trace_btrfs_space_reservation(fs_info, "transaction",
652 h->transid, num_bytes, 1);
653 h->block_rsv = &fs_info->trans_block_rsv;
654 h->bytes_reserved = num_bytes;
655 h->reloc_reserved = reloc_reserved;
659 btrfs_record_root_in_trans(h, root);
661 if (!current->journal_info)
662 current->journal_info = h;
666 if (type & __TRANS_FREEZABLE)
667 sb_end_intwrite(fs_info->sb);
668 kmem_cache_free(btrfs_trans_handle_cachep, h);
671 btrfs_block_rsv_release(fs_info, &fs_info->trans_block_rsv,
674 btrfs_qgroup_free_meta_pertrans(root, qgroup_reserved);
678 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
679 unsigned int num_items)
681 return start_transaction(root, num_items, TRANS_START,
682 BTRFS_RESERVE_FLUSH_ALL, true);
685 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
686 struct btrfs_root *root,
687 unsigned int num_items,
690 struct btrfs_fs_info *fs_info = root->fs_info;
691 struct btrfs_trans_handle *trans;
696 * We have two callers: unlink and block group removal. The
697 * former should succeed even if we will temporarily exceed
698 * quota and the latter operates on the extent root so
699 * qgroup enforcement is ignored anyway.
701 trans = start_transaction(root, num_items, TRANS_START,
702 BTRFS_RESERVE_FLUSH_ALL, false);
703 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
706 trans = btrfs_start_transaction(root, 0);
710 num_bytes = btrfs_calc_insert_metadata_size(fs_info, num_items);
711 ret = btrfs_cond_migrate_bytes(fs_info, &fs_info->trans_block_rsv,
712 num_bytes, min_factor);
714 btrfs_end_transaction(trans);
718 trans->block_rsv = &fs_info->trans_block_rsv;
719 trans->bytes_reserved = num_bytes;
720 trace_btrfs_space_reservation(fs_info, "transaction",
721 trans->transid, num_bytes, 1);
726 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root)
728 return start_transaction(root, 0, TRANS_JOIN, BTRFS_RESERVE_NO_FLUSH,
732 struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root)
734 return start_transaction(root, 0, TRANS_JOIN_NOLOCK,
735 BTRFS_RESERVE_NO_FLUSH, true);
739 * Similar to regular join but it never starts a transaction when none is
740 * running or after waiting for the current one to finish.
742 struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root)
744 return start_transaction(root, 0, TRANS_JOIN_NOSTART,
745 BTRFS_RESERVE_NO_FLUSH, true);
749 * btrfs_attach_transaction() - catch the running transaction
751 * It is used when we want to commit the current the transaction, but
752 * don't want to start a new one.
754 * Note: If this function return -ENOENT, it just means there is no
755 * running transaction. But it is possible that the inactive transaction
756 * is still in the memory, not fully on disk. If you hope there is no
757 * inactive transaction in the fs when -ENOENT is returned, you should
759 * btrfs_attach_transaction_barrier()
761 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root)
763 return start_transaction(root, 0, TRANS_ATTACH,
764 BTRFS_RESERVE_NO_FLUSH, true);
768 * btrfs_attach_transaction_barrier() - catch the running transaction
770 * It is similar to the above function, the difference is this one
771 * will wait for all the inactive transactions until they fully
774 struct btrfs_trans_handle *
775 btrfs_attach_transaction_barrier(struct btrfs_root *root)
777 struct btrfs_trans_handle *trans;
779 trans = start_transaction(root, 0, TRANS_ATTACH,
780 BTRFS_RESERVE_NO_FLUSH, true);
781 if (trans == ERR_PTR(-ENOENT))
782 btrfs_wait_for_commit(root->fs_info, 0);
787 /* wait for a transaction commit to be fully complete */
788 static noinline void wait_for_commit(struct btrfs_transaction *commit)
790 wait_event(commit->commit_wait, commit->state == TRANS_STATE_COMPLETED);
793 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid)
795 struct btrfs_transaction *cur_trans = NULL, *t;
799 if (transid <= fs_info->last_trans_committed)
802 /* find specified transaction */
803 spin_lock(&fs_info->trans_lock);
804 list_for_each_entry(t, &fs_info->trans_list, list) {
805 if (t->transid == transid) {
807 refcount_inc(&cur_trans->use_count);
811 if (t->transid > transid) {
816 spin_unlock(&fs_info->trans_lock);
819 * The specified transaction doesn't exist, or we
820 * raced with btrfs_commit_transaction
823 if (transid > fs_info->last_trans_committed)
828 /* find newest transaction that is committing | committed */
829 spin_lock(&fs_info->trans_lock);
830 list_for_each_entry_reverse(t, &fs_info->trans_list,
832 if (t->state >= TRANS_STATE_COMMIT_START) {
833 if (t->state == TRANS_STATE_COMPLETED)
836 refcount_inc(&cur_trans->use_count);
840 spin_unlock(&fs_info->trans_lock);
842 goto out; /* nothing committing|committed */
845 wait_for_commit(cur_trans);
846 btrfs_put_transaction(cur_trans);
851 void btrfs_throttle(struct btrfs_fs_info *fs_info)
853 wait_current_trans(fs_info);
856 static int should_end_transaction(struct btrfs_trans_handle *trans)
858 struct btrfs_fs_info *fs_info = trans->fs_info;
860 if (btrfs_check_space_for_delayed_refs(fs_info))
863 return !!btrfs_block_rsv_check(&fs_info->global_block_rsv, 5);
866 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans)
868 struct btrfs_transaction *cur_trans = trans->transaction;
871 if (cur_trans->state >= TRANS_STATE_COMMIT_START ||
872 cur_trans->delayed_refs.flushing)
875 return should_end_transaction(trans);
878 static void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans)
881 struct btrfs_fs_info *fs_info = trans->fs_info;
883 if (!trans->block_rsv) {
884 ASSERT(!trans->bytes_reserved);
888 if (!trans->bytes_reserved)
891 ASSERT(trans->block_rsv == &fs_info->trans_block_rsv);
892 trace_btrfs_space_reservation(fs_info, "transaction",
893 trans->transid, trans->bytes_reserved, 0);
894 btrfs_block_rsv_release(fs_info, trans->block_rsv,
895 trans->bytes_reserved);
896 trans->bytes_reserved = 0;
899 static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
902 struct btrfs_fs_info *info = trans->fs_info;
903 struct btrfs_transaction *cur_trans = trans->transaction;
906 if (refcount_read(&trans->use_count) > 1) {
907 refcount_dec(&trans->use_count);
908 trans->block_rsv = trans->orig_rsv;
912 btrfs_trans_release_metadata(trans);
913 trans->block_rsv = NULL;
915 btrfs_create_pending_block_groups(trans);
917 btrfs_trans_release_chunk_metadata(trans);
919 if (trans->type & __TRANS_FREEZABLE)
920 sb_end_intwrite(info->sb);
922 WARN_ON(cur_trans != info->running_transaction);
923 WARN_ON(atomic_read(&cur_trans->num_writers) < 1);
924 atomic_dec(&cur_trans->num_writers);
925 extwriter_counter_dec(cur_trans, trans->type);
927 cond_wake_up(&cur_trans->writer_wait);
928 btrfs_put_transaction(cur_trans);
930 if (current->journal_info == trans)
931 current->journal_info = NULL;
934 btrfs_run_delayed_iputs(info);
936 if (trans->aborted ||
937 test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) {
938 wake_up_process(info->transaction_kthread);
942 kmem_cache_free(btrfs_trans_handle_cachep, trans);
946 int btrfs_end_transaction(struct btrfs_trans_handle *trans)
948 return __btrfs_end_transaction(trans, 0);
951 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans)
953 return __btrfs_end_transaction(trans, 1);
957 * when btree blocks are allocated, they have some corresponding bits set for
958 * them in one of two extent_io trees. This is used to make sure all of
959 * those extents are sent to disk but does not wait on them
961 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
962 struct extent_io_tree *dirty_pages, int mark)
966 struct address_space *mapping = fs_info->btree_inode->i_mapping;
967 struct extent_state *cached_state = NULL;
971 atomic_inc(&BTRFS_I(fs_info->btree_inode)->sync_writers);
972 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
973 mark, &cached_state)) {
974 bool wait_writeback = false;
976 err = convert_extent_bit(dirty_pages, start, end,
978 mark, &cached_state);
980 * convert_extent_bit can return -ENOMEM, which is most of the
981 * time a temporary error. So when it happens, ignore the error
982 * and wait for writeback of this range to finish - because we
983 * failed to set the bit EXTENT_NEED_WAIT for the range, a call
984 * to __btrfs_wait_marked_extents() would not know that
985 * writeback for this range started and therefore wouldn't
986 * wait for it to finish - we don't want to commit a
987 * superblock that points to btree nodes/leafs for which
988 * writeback hasn't finished yet (and without errors).
989 * We cleanup any entries left in the io tree when committing
990 * the transaction (through extent_io_tree_release()).
992 if (err == -ENOMEM) {
994 wait_writeback = true;
997 err = filemap_fdatawrite_range(mapping, start, end);
1000 else if (wait_writeback)
1001 werr = filemap_fdatawait_range(mapping, start, end);
1002 free_extent_state(cached_state);
1003 cached_state = NULL;
1007 atomic_dec(&BTRFS_I(fs_info->btree_inode)->sync_writers);
1012 * when btree blocks are allocated, they have some corresponding bits set for
1013 * them in one of two extent_io trees. This is used to make sure all of
1014 * those extents are on disk for transaction or log commit. We wait
1015 * on all the pages and clear them from the dirty pages state tree
1017 static int __btrfs_wait_marked_extents(struct btrfs_fs_info *fs_info,
1018 struct extent_io_tree *dirty_pages)
1022 struct address_space *mapping = fs_info->btree_inode->i_mapping;
1023 struct extent_state *cached_state = NULL;
1027 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
1028 EXTENT_NEED_WAIT, &cached_state)) {
1030 * Ignore -ENOMEM errors returned by clear_extent_bit().
1031 * When committing the transaction, we'll remove any entries
1032 * left in the io tree. For a log commit, we don't remove them
1033 * after committing the log because the tree can be accessed
1034 * concurrently - we do it only at transaction commit time when
1035 * it's safe to do it (through extent_io_tree_release()).
1037 err = clear_extent_bit(dirty_pages, start, end,
1038 EXTENT_NEED_WAIT, 0, 0, &cached_state);
1042 err = filemap_fdatawait_range(mapping, start, end);
1045 free_extent_state(cached_state);
1046 cached_state = NULL;
1055 static int btrfs_wait_extents(struct btrfs_fs_info *fs_info,
1056 struct extent_io_tree *dirty_pages)
1058 bool errors = false;
1061 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
1062 if (test_and_clear_bit(BTRFS_FS_BTREE_ERR, &fs_info->flags))
1070 int btrfs_wait_tree_log_extents(struct btrfs_root *log_root, int mark)
1072 struct btrfs_fs_info *fs_info = log_root->fs_info;
1073 struct extent_io_tree *dirty_pages = &log_root->dirty_log_pages;
1074 bool errors = false;
1077 ASSERT(log_root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
1079 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
1080 if ((mark & EXTENT_DIRTY) &&
1081 test_and_clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags))
1084 if ((mark & EXTENT_NEW) &&
1085 test_and_clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags))
1094 * When btree blocks are allocated the corresponding extents are marked dirty.
1095 * This function ensures such extents are persisted on disk for transaction or
1098 * @trans: transaction whose dirty pages we'd like to write
1100 static int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans)
1104 struct extent_io_tree *dirty_pages = &trans->transaction->dirty_pages;
1105 struct btrfs_fs_info *fs_info = trans->fs_info;
1106 struct blk_plug plug;
1108 blk_start_plug(&plug);
1109 ret = btrfs_write_marked_extents(fs_info, dirty_pages, EXTENT_DIRTY);
1110 blk_finish_plug(&plug);
1111 ret2 = btrfs_wait_extents(fs_info, dirty_pages);
1113 extent_io_tree_release(&trans->transaction->dirty_pages);
1124 * this is used to update the root pointer in the tree of tree roots.
1126 * But, in the case of the extent allocation tree, updating the root
1127 * pointer may allocate blocks which may change the root of the extent
1130 * So, this loops and repeats and makes sure the cowonly root didn't
1131 * change while the root pointer was being updated in the metadata.
1133 static int update_cowonly_root(struct btrfs_trans_handle *trans,
1134 struct btrfs_root *root)
1137 u64 old_root_bytenr;
1139 struct btrfs_fs_info *fs_info = root->fs_info;
1140 struct btrfs_root *tree_root = fs_info->tree_root;
1142 old_root_used = btrfs_root_used(&root->root_item);
1145 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
1146 if (old_root_bytenr == root->node->start &&
1147 old_root_used == btrfs_root_used(&root->root_item))
1150 btrfs_set_root_node(&root->root_item, root->node);
1151 ret = btrfs_update_root(trans, tree_root,
1157 old_root_used = btrfs_root_used(&root->root_item);
1164 * update all the cowonly tree roots on disk
1166 * The error handling in this function may not be obvious. Any of the
1167 * failures will cause the file system to go offline. We still need
1168 * to clean up the delayed refs.
1170 static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans)
1172 struct btrfs_fs_info *fs_info = trans->fs_info;
1173 struct list_head *dirty_bgs = &trans->transaction->dirty_bgs;
1174 struct list_head *io_bgs = &trans->transaction->io_bgs;
1175 struct list_head *next;
1176 struct extent_buffer *eb;
1179 eb = btrfs_lock_root_node(fs_info->tree_root);
1180 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL,
1182 btrfs_tree_unlock(eb);
1183 free_extent_buffer(eb);
1188 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1192 ret = btrfs_run_dev_stats(trans);
1195 ret = btrfs_run_dev_replace(trans);
1198 ret = btrfs_run_qgroups(trans);
1202 ret = btrfs_setup_space_cache(trans);
1206 /* run_qgroups might have added some more refs */
1207 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1211 while (!list_empty(&fs_info->dirty_cowonly_roots)) {
1212 struct btrfs_root *root;
1213 next = fs_info->dirty_cowonly_roots.next;
1214 list_del_init(next);
1215 root = list_entry(next, struct btrfs_root, dirty_list);
1216 clear_bit(BTRFS_ROOT_DIRTY, &root->state);
1218 if (root != fs_info->extent_root)
1219 list_add_tail(&root->dirty_list,
1220 &trans->transaction->switch_commits);
1221 ret = update_cowonly_root(trans, root);
1224 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1229 while (!list_empty(dirty_bgs) || !list_empty(io_bgs)) {
1230 ret = btrfs_write_dirty_block_groups(trans);
1233 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1238 if (!list_empty(&fs_info->dirty_cowonly_roots))
1241 list_add_tail(&fs_info->extent_root->dirty_list,
1242 &trans->transaction->switch_commits);
1244 /* Update dev-replace pointer once everything is committed */
1245 fs_info->dev_replace.committed_cursor_left =
1246 fs_info->dev_replace.cursor_left_last_write_of_item;
1252 * dead roots are old snapshots that need to be deleted. This allocates
1253 * a dirty root struct and adds it into the list of dead roots that need to
1256 void btrfs_add_dead_root(struct btrfs_root *root)
1258 struct btrfs_fs_info *fs_info = root->fs_info;
1260 spin_lock(&fs_info->trans_lock);
1261 if (list_empty(&root->root_list))
1262 list_add_tail(&root->root_list, &fs_info->dead_roots);
1263 spin_unlock(&fs_info->trans_lock);
1267 * update all the cowonly tree roots on disk
1269 static noinline int commit_fs_roots(struct btrfs_trans_handle *trans)
1271 struct btrfs_fs_info *fs_info = trans->fs_info;
1272 struct btrfs_root *gang[8];
1277 spin_lock(&fs_info->fs_roots_radix_lock);
1279 ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
1282 BTRFS_ROOT_TRANS_TAG);
1285 for (i = 0; i < ret; i++) {
1286 struct btrfs_root *root = gang[i];
1287 radix_tree_tag_clear(&fs_info->fs_roots_radix,
1288 (unsigned long)root->root_key.objectid,
1289 BTRFS_ROOT_TRANS_TAG);
1290 spin_unlock(&fs_info->fs_roots_radix_lock);
1292 btrfs_free_log(trans, root);
1293 btrfs_update_reloc_root(trans, root);
1295 btrfs_save_ino_cache(root, trans);
1297 /* see comments in should_cow_block() */
1298 clear_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1299 smp_mb__after_atomic();
1301 if (root->commit_root != root->node) {
1302 list_add_tail(&root->dirty_list,
1303 &trans->transaction->switch_commits);
1304 btrfs_set_root_node(&root->root_item,
1308 err = btrfs_update_root(trans, fs_info->tree_root,
1311 spin_lock(&fs_info->fs_roots_radix_lock);
1314 btrfs_qgroup_free_meta_all_pertrans(root);
1317 spin_unlock(&fs_info->fs_roots_radix_lock);
1322 * defrag a given btree.
1323 * Every leaf in the btree is read and defragged.
1325 int btrfs_defrag_root(struct btrfs_root *root)
1327 struct btrfs_fs_info *info = root->fs_info;
1328 struct btrfs_trans_handle *trans;
1331 if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state))
1335 trans = btrfs_start_transaction(root, 0);
1337 return PTR_ERR(trans);
1339 ret = btrfs_defrag_leaves(trans, root);
1341 btrfs_end_transaction(trans);
1342 btrfs_btree_balance_dirty(info);
1345 if (btrfs_fs_closing(info) || ret != -EAGAIN)
1348 if (btrfs_defrag_cancelled(info)) {
1349 btrfs_debug(info, "defrag_root cancelled");
1354 clear_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state);
1359 * Do all special snapshot related qgroup dirty hack.
1361 * Will do all needed qgroup inherit and dirty hack like switch commit
1362 * roots inside one transaction and write all btree into disk, to make
1365 static int qgroup_account_snapshot(struct btrfs_trans_handle *trans,
1366 struct btrfs_root *src,
1367 struct btrfs_root *parent,
1368 struct btrfs_qgroup_inherit *inherit,
1371 struct btrfs_fs_info *fs_info = src->fs_info;
1375 * Save some performance in the case that qgroups are not
1376 * enabled. If this check races with the ioctl, rescan will
1379 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1383 * Ensure dirty @src will be committed. Or, after coming
1384 * commit_fs_roots() and switch_commit_roots(), any dirty but not
1385 * recorded root will never be updated again, causing an outdated root
1388 record_root_in_trans(trans, src, 1);
1391 * We are going to commit transaction, see btrfs_commit_transaction()
1392 * comment for reason locking tree_log_mutex
1394 mutex_lock(&fs_info->tree_log_mutex);
1396 ret = commit_fs_roots(trans);
1399 ret = btrfs_qgroup_account_extents(trans);
1403 /* Now qgroup are all updated, we can inherit it to new qgroups */
1404 ret = btrfs_qgroup_inherit(trans, src->root_key.objectid, dst_objectid,
1410 * Now we do a simplified commit transaction, which will:
1411 * 1) commit all subvolume and extent tree
1412 * To ensure all subvolume and extent tree have a valid
1413 * commit_root to accounting later insert_dir_item()
1414 * 2) write all btree blocks onto disk
1415 * This is to make sure later btree modification will be cowed
1416 * Or commit_root can be populated and cause wrong qgroup numbers
1417 * In this simplified commit, we don't really care about other trees
1418 * like chunk and root tree, as they won't affect qgroup.
1419 * And we don't write super to avoid half committed status.
1421 ret = commit_cowonly_roots(trans);
1424 switch_commit_roots(trans->transaction);
1425 ret = btrfs_write_and_wait_transaction(trans);
1427 btrfs_handle_fs_error(fs_info, ret,
1428 "Error while writing out transaction for qgroup");
1431 mutex_unlock(&fs_info->tree_log_mutex);
1434 * Force parent root to be updated, as we recorded it before so its
1435 * last_trans == cur_transid.
1436 * Or it won't be committed again onto disk after later
1440 record_root_in_trans(trans, parent, 1);
1445 * new snapshots need to be created at a very specific time in the
1446 * transaction commit. This does the actual creation.
1449 * If the error which may affect the commitment of the current transaction
1450 * happens, we should return the error number. If the error which just affect
1451 * the creation of the pending snapshots, just return 0.
1453 static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
1454 struct btrfs_pending_snapshot *pending)
1457 struct btrfs_fs_info *fs_info = trans->fs_info;
1458 struct btrfs_key key;
1459 struct btrfs_root_item *new_root_item;
1460 struct btrfs_root *tree_root = fs_info->tree_root;
1461 struct btrfs_root *root = pending->root;
1462 struct btrfs_root *parent_root;
1463 struct btrfs_block_rsv *rsv;
1464 struct inode *parent_inode;
1465 struct btrfs_path *path;
1466 struct btrfs_dir_item *dir_item;
1467 struct dentry *dentry;
1468 struct extent_buffer *tmp;
1469 struct extent_buffer *old;
1470 struct timespec64 cur_time;
1478 ASSERT(pending->path);
1479 path = pending->path;
1481 ASSERT(pending->root_item);
1482 new_root_item = pending->root_item;
1484 pending->error = btrfs_find_free_objectid(tree_root, &objectid);
1486 goto no_free_objectid;
1489 * Make qgroup to skip current new snapshot's qgroupid, as it is
1490 * accounted by later btrfs_qgroup_inherit().
1492 btrfs_set_skip_qgroup(trans, objectid);
1494 btrfs_reloc_pre_snapshot(pending, &to_reserve);
1496 if (to_reserve > 0) {
1497 pending->error = btrfs_block_rsv_add(root,
1498 &pending->block_rsv,
1500 BTRFS_RESERVE_NO_FLUSH);
1502 goto clear_skip_qgroup;
1505 key.objectid = objectid;
1506 key.offset = (u64)-1;
1507 key.type = BTRFS_ROOT_ITEM_KEY;
1509 rsv = trans->block_rsv;
1510 trans->block_rsv = &pending->block_rsv;
1511 trans->bytes_reserved = trans->block_rsv->reserved;
1512 trace_btrfs_space_reservation(fs_info, "transaction",
1514 trans->bytes_reserved, 1);
1515 dentry = pending->dentry;
1516 parent_inode = pending->dir;
1517 parent_root = BTRFS_I(parent_inode)->root;
1518 record_root_in_trans(trans, parent_root, 0);
1520 cur_time = current_time(parent_inode);
1523 * insert the directory item
1525 ret = btrfs_set_inode_index(BTRFS_I(parent_inode), &index);
1526 BUG_ON(ret); /* -ENOMEM */
1528 /* check if there is a file/dir which has the same name. */
1529 dir_item = btrfs_lookup_dir_item(NULL, parent_root, path,
1530 btrfs_ino(BTRFS_I(parent_inode)),
1531 dentry->d_name.name,
1532 dentry->d_name.len, 0);
1533 if (dir_item != NULL && !IS_ERR(dir_item)) {
1534 pending->error = -EEXIST;
1535 goto dir_item_existed;
1536 } else if (IS_ERR(dir_item)) {
1537 ret = PTR_ERR(dir_item);
1538 btrfs_abort_transaction(trans, ret);
1541 btrfs_release_path(path);
1544 * pull in the delayed directory update
1545 * and the delayed inode item
1546 * otherwise we corrupt the FS during
1549 ret = btrfs_run_delayed_items(trans);
1550 if (ret) { /* Transaction aborted */
1551 btrfs_abort_transaction(trans, ret);
1555 record_root_in_trans(trans, root, 0);
1556 btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
1557 memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
1558 btrfs_check_and_init_root_item(new_root_item);
1560 root_flags = btrfs_root_flags(new_root_item);
1561 if (pending->readonly)
1562 root_flags |= BTRFS_ROOT_SUBVOL_RDONLY;
1564 root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY;
1565 btrfs_set_root_flags(new_root_item, root_flags);
1567 btrfs_set_root_generation_v2(new_root_item,
1569 uuid_le_gen(&new_uuid);
1570 memcpy(new_root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
1571 memcpy(new_root_item->parent_uuid, root->root_item.uuid,
1573 if (!(root_flags & BTRFS_ROOT_SUBVOL_RDONLY)) {
1574 memset(new_root_item->received_uuid, 0,
1575 sizeof(new_root_item->received_uuid));
1576 memset(&new_root_item->stime, 0, sizeof(new_root_item->stime));
1577 memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime));
1578 btrfs_set_root_stransid(new_root_item, 0);
1579 btrfs_set_root_rtransid(new_root_item, 0);
1581 btrfs_set_stack_timespec_sec(&new_root_item->otime, cur_time.tv_sec);
1582 btrfs_set_stack_timespec_nsec(&new_root_item->otime, cur_time.tv_nsec);
1583 btrfs_set_root_otransid(new_root_item, trans->transid);
1585 old = btrfs_lock_root_node(root);
1586 ret = btrfs_cow_block(trans, root, old, NULL, 0, &old);
1588 btrfs_tree_unlock(old);
1589 free_extent_buffer(old);
1590 btrfs_abort_transaction(trans, ret);
1594 btrfs_set_lock_blocking_write(old);
1596 ret = btrfs_copy_root(trans, root, old, &tmp, objectid);
1597 /* clean up in any case */
1598 btrfs_tree_unlock(old);
1599 free_extent_buffer(old);
1601 btrfs_abort_transaction(trans, ret);
1604 /* see comments in should_cow_block() */
1605 set_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1608 btrfs_set_root_node(new_root_item, tmp);
1609 /* record when the snapshot was created in key.offset */
1610 key.offset = trans->transid;
1611 ret = btrfs_insert_root(trans, tree_root, &key, new_root_item);
1612 btrfs_tree_unlock(tmp);
1613 free_extent_buffer(tmp);
1615 btrfs_abort_transaction(trans, ret);
1620 * insert root back/forward references
1622 ret = btrfs_add_root_ref(trans, objectid,
1623 parent_root->root_key.objectid,
1624 btrfs_ino(BTRFS_I(parent_inode)), index,
1625 dentry->d_name.name, dentry->d_name.len);
1627 btrfs_abort_transaction(trans, ret);
1631 key.offset = (u64)-1;
1632 pending->snap = btrfs_read_fs_root_no_name(fs_info, &key);
1633 if (IS_ERR(pending->snap)) {
1634 ret = PTR_ERR(pending->snap);
1635 btrfs_abort_transaction(trans, ret);
1639 ret = btrfs_reloc_post_snapshot(trans, pending);
1641 btrfs_abort_transaction(trans, ret);
1645 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1647 btrfs_abort_transaction(trans, ret);
1652 * Do special qgroup accounting for snapshot, as we do some qgroup
1653 * snapshot hack to do fast snapshot.
1654 * To co-operate with that hack, we do hack again.
1655 * Or snapshot will be greatly slowed down by a subtree qgroup rescan
1657 ret = qgroup_account_snapshot(trans, root, parent_root,
1658 pending->inherit, objectid);
1662 ret = btrfs_insert_dir_item(trans, dentry->d_name.name,
1663 dentry->d_name.len, BTRFS_I(parent_inode),
1664 &key, BTRFS_FT_DIR, index);
1665 /* We have check then name at the beginning, so it is impossible. */
1666 BUG_ON(ret == -EEXIST || ret == -EOVERFLOW);
1668 btrfs_abort_transaction(trans, ret);
1672 btrfs_i_size_write(BTRFS_I(parent_inode), parent_inode->i_size +
1673 dentry->d_name.len * 2);
1674 parent_inode->i_mtime = parent_inode->i_ctime =
1675 current_time(parent_inode);
1676 ret = btrfs_update_inode_fallback(trans, parent_root, parent_inode);
1678 btrfs_abort_transaction(trans, ret);
1681 ret = btrfs_uuid_tree_add(trans, new_uuid.b, BTRFS_UUID_KEY_SUBVOL,
1684 btrfs_abort_transaction(trans, ret);
1687 if (!btrfs_is_empty_uuid(new_root_item->received_uuid)) {
1688 ret = btrfs_uuid_tree_add(trans, new_root_item->received_uuid,
1689 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
1691 if (ret && ret != -EEXIST) {
1692 btrfs_abort_transaction(trans, ret);
1697 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1699 btrfs_abort_transaction(trans, ret);
1704 pending->error = ret;
1706 trans->block_rsv = rsv;
1707 trans->bytes_reserved = 0;
1709 btrfs_clear_skip_qgroup(trans);
1711 kfree(new_root_item);
1712 pending->root_item = NULL;
1713 btrfs_free_path(path);
1714 pending->path = NULL;
1720 * create all the snapshots we've scheduled for creation
1722 static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans)
1724 struct btrfs_pending_snapshot *pending, *next;
1725 struct list_head *head = &trans->transaction->pending_snapshots;
1728 list_for_each_entry_safe(pending, next, head, list) {
1729 list_del(&pending->list);
1730 ret = create_pending_snapshot(trans, pending);
1737 static void update_super_roots(struct btrfs_fs_info *fs_info)
1739 struct btrfs_root_item *root_item;
1740 struct btrfs_super_block *super;
1742 super = fs_info->super_copy;
1744 root_item = &fs_info->chunk_root->root_item;
1745 super->chunk_root = root_item->bytenr;
1746 super->chunk_root_generation = root_item->generation;
1747 super->chunk_root_level = root_item->level;
1749 root_item = &fs_info->tree_root->root_item;
1750 super->root = root_item->bytenr;
1751 super->generation = root_item->generation;
1752 super->root_level = root_item->level;
1753 if (btrfs_test_opt(fs_info, SPACE_CACHE))
1754 super->cache_generation = root_item->generation;
1755 if (test_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags))
1756 super->uuid_tree_generation = root_item->generation;
1759 int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
1761 struct btrfs_transaction *trans;
1764 spin_lock(&info->trans_lock);
1765 trans = info->running_transaction;
1767 ret = (trans->state >= TRANS_STATE_COMMIT_START);
1768 spin_unlock(&info->trans_lock);
1772 int btrfs_transaction_blocked(struct btrfs_fs_info *info)
1774 struct btrfs_transaction *trans;
1777 spin_lock(&info->trans_lock);
1778 trans = info->running_transaction;
1780 ret = is_transaction_blocked(trans);
1781 spin_unlock(&info->trans_lock);
1786 * wait for the current transaction commit to start and block subsequent
1789 static void wait_current_trans_commit_start(struct btrfs_fs_info *fs_info,
1790 struct btrfs_transaction *trans)
1792 wait_event(fs_info->transaction_blocked_wait,
1793 trans->state >= TRANS_STATE_COMMIT_START || trans->aborted);
1797 * wait for the current transaction to start and then become unblocked.
1800 static void wait_current_trans_commit_start_and_unblock(
1801 struct btrfs_fs_info *fs_info,
1802 struct btrfs_transaction *trans)
1804 wait_event(fs_info->transaction_wait,
1805 trans->state >= TRANS_STATE_UNBLOCKED || trans->aborted);
1809 * commit transactions asynchronously. once btrfs_commit_transaction_async
1810 * returns, any subsequent transaction will not be allowed to join.
1812 struct btrfs_async_commit {
1813 struct btrfs_trans_handle *newtrans;
1814 struct work_struct work;
1817 static void do_async_commit(struct work_struct *work)
1819 struct btrfs_async_commit *ac =
1820 container_of(work, struct btrfs_async_commit, work);
1823 * We've got freeze protection passed with the transaction.
1824 * Tell lockdep about it.
1826 if (ac->newtrans->type & __TRANS_FREEZABLE)
1827 __sb_writers_acquired(ac->newtrans->fs_info->sb, SB_FREEZE_FS);
1829 current->journal_info = ac->newtrans;
1831 btrfs_commit_transaction(ac->newtrans);
1835 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
1836 int wait_for_unblock)
1838 struct btrfs_fs_info *fs_info = trans->fs_info;
1839 struct btrfs_async_commit *ac;
1840 struct btrfs_transaction *cur_trans;
1842 ac = kmalloc(sizeof(*ac), GFP_NOFS);
1846 INIT_WORK(&ac->work, do_async_commit);
1847 ac->newtrans = btrfs_join_transaction(trans->root);
1848 if (IS_ERR(ac->newtrans)) {
1849 int err = PTR_ERR(ac->newtrans);
1854 /* take transaction reference */
1855 cur_trans = trans->transaction;
1856 refcount_inc(&cur_trans->use_count);
1858 btrfs_end_transaction(trans);
1861 * Tell lockdep we've released the freeze rwsem, since the
1862 * async commit thread will be the one to unlock it.
1864 if (ac->newtrans->type & __TRANS_FREEZABLE)
1865 __sb_writers_release(fs_info->sb, SB_FREEZE_FS);
1867 schedule_work(&ac->work);
1869 /* wait for transaction to start and unblock */
1870 if (wait_for_unblock)
1871 wait_current_trans_commit_start_and_unblock(fs_info, cur_trans);
1873 wait_current_trans_commit_start(fs_info, cur_trans);
1875 if (current->journal_info == trans)
1876 current->journal_info = NULL;
1878 btrfs_put_transaction(cur_trans);
1883 static void cleanup_transaction(struct btrfs_trans_handle *trans, int err)
1885 struct btrfs_fs_info *fs_info = trans->fs_info;
1886 struct btrfs_transaction *cur_trans = trans->transaction;
1888 WARN_ON(refcount_read(&trans->use_count) > 1);
1890 btrfs_abort_transaction(trans, err);
1892 spin_lock(&fs_info->trans_lock);
1895 * If the transaction is removed from the list, it means this
1896 * transaction has been committed successfully, so it is impossible
1897 * to call the cleanup function.
1899 BUG_ON(list_empty(&cur_trans->list));
1901 list_del_init(&cur_trans->list);
1902 if (cur_trans == fs_info->running_transaction) {
1903 cur_trans->state = TRANS_STATE_COMMIT_DOING;
1904 spin_unlock(&fs_info->trans_lock);
1905 wait_event(cur_trans->writer_wait,
1906 atomic_read(&cur_trans->num_writers) == 1);
1908 spin_lock(&fs_info->trans_lock);
1910 spin_unlock(&fs_info->trans_lock);
1912 btrfs_cleanup_one_transaction(trans->transaction, fs_info);
1914 spin_lock(&fs_info->trans_lock);
1915 if (cur_trans == fs_info->running_transaction)
1916 fs_info->running_transaction = NULL;
1917 spin_unlock(&fs_info->trans_lock);
1919 if (trans->type & __TRANS_FREEZABLE)
1920 sb_end_intwrite(fs_info->sb);
1921 btrfs_put_transaction(cur_trans);
1922 btrfs_put_transaction(cur_trans);
1924 trace_btrfs_transaction_commit(trans->root);
1926 if (current->journal_info == trans)
1927 current->journal_info = NULL;
1928 btrfs_scrub_cancel(fs_info);
1930 kmem_cache_free(btrfs_trans_handle_cachep, trans);
1934 * Release reserved delayed ref space of all pending block groups of the
1935 * transaction and remove them from the list
1937 static void btrfs_cleanup_pending_block_groups(struct btrfs_trans_handle *trans)
1939 struct btrfs_fs_info *fs_info = trans->fs_info;
1940 struct btrfs_block_group *block_group, *tmp;
1942 list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
1943 btrfs_delayed_refs_rsv_release(fs_info, 1);
1944 list_del_init(&block_group->bg_list);
1948 static inline int btrfs_start_delalloc_flush(struct btrfs_trans_handle *trans)
1950 struct btrfs_fs_info *fs_info = trans->fs_info;
1953 * We use writeback_inodes_sb here because if we used
1954 * btrfs_start_delalloc_roots we would deadlock with fs freeze.
1955 * Currently are holding the fs freeze lock, if we do an async flush
1956 * we'll do btrfs_join_transaction() and deadlock because we need to
1957 * wait for the fs freeze lock. Using the direct flushing we benefit
1958 * from already being in a transaction and our join_transaction doesn't
1959 * have to re-take the fs freeze lock.
1961 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) {
1962 writeback_inodes_sb(fs_info->sb, WB_REASON_SYNC);
1964 struct btrfs_pending_snapshot *pending;
1965 struct list_head *head = &trans->transaction->pending_snapshots;
1968 * Flush dellaloc for any root that is going to be snapshotted.
1969 * This is done to avoid a corrupted version of files, in the
1970 * snapshots, that had both buffered and direct IO writes (even
1971 * if they were done sequentially) due to an unordered update of
1972 * the inode's size on disk.
1974 list_for_each_entry(pending, head, list) {
1977 ret = btrfs_start_delalloc_snapshot(pending->root);
1985 static inline void btrfs_wait_delalloc_flush(struct btrfs_trans_handle *trans)
1987 struct btrfs_fs_info *fs_info = trans->fs_info;
1989 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT)) {
1990 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
1992 struct btrfs_pending_snapshot *pending;
1993 struct list_head *head = &trans->transaction->pending_snapshots;
1996 * Wait for any dellaloc that we started previously for the roots
1997 * that are going to be snapshotted. This is to avoid a corrupted
1998 * version of files in the snapshots that had both buffered and
1999 * direct IO writes (even if they were done sequentially).
2001 list_for_each_entry(pending, head, list)
2002 btrfs_wait_ordered_extents(pending->root,
2003 U64_MAX, 0, U64_MAX);
2007 int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
2009 struct btrfs_fs_info *fs_info = trans->fs_info;
2010 struct btrfs_transaction *cur_trans = trans->transaction;
2011 struct btrfs_transaction *prev_trans = NULL;
2014 ASSERT(refcount_read(&trans->use_count) == 1);
2016 /* Stop the commit early if ->aborted is set */
2017 if (unlikely(READ_ONCE(cur_trans->aborted))) {
2018 ret = cur_trans->aborted;
2019 btrfs_end_transaction(trans);
2023 btrfs_trans_release_metadata(trans);
2024 trans->block_rsv = NULL;
2026 /* make a pass through all the delayed refs we have so far
2027 * any runnings procs may add more while we are here
2029 ret = btrfs_run_delayed_refs(trans, 0);
2031 btrfs_end_transaction(trans);
2035 cur_trans = trans->transaction;
2038 * set the flushing flag so procs in this transaction have to
2039 * start sending their work down.
2041 cur_trans->delayed_refs.flushing = 1;
2044 btrfs_create_pending_block_groups(trans);
2046 ret = btrfs_run_delayed_refs(trans, 0);
2048 btrfs_end_transaction(trans);
2052 if (!test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &cur_trans->flags)) {
2055 /* this mutex is also taken before trying to set
2056 * block groups readonly. We need to make sure
2057 * that nobody has set a block group readonly
2058 * after a extents from that block group have been
2059 * allocated for cache files. btrfs_set_block_group_ro
2060 * will wait for the transaction to commit if it
2061 * finds BTRFS_TRANS_DIRTY_BG_RUN set.
2063 * The BTRFS_TRANS_DIRTY_BG_RUN flag is also used to make sure
2064 * only one process starts all the block group IO. It wouldn't
2065 * hurt to have more than one go through, but there's no
2066 * real advantage to it either.
2068 mutex_lock(&fs_info->ro_block_group_mutex);
2069 if (!test_and_set_bit(BTRFS_TRANS_DIRTY_BG_RUN,
2072 mutex_unlock(&fs_info->ro_block_group_mutex);
2075 ret = btrfs_start_dirty_block_groups(trans);
2077 btrfs_end_transaction(trans);
2083 spin_lock(&fs_info->trans_lock);
2084 if (cur_trans->state >= TRANS_STATE_COMMIT_START) {
2085 spin_unlock(&fs_info->trans_lock);
2086 refcount_inc(&cur_trans->use_count);
2087 ret = btrfs_end_transaction(trans);
2089 wait_for_commit(cur_trans);
2091 if (unlikely(cur_trans->aborted))
2092 ret = cur_trans->aborted;
2094 btrfs_put_transaction(cur_trans);
2099 cur_trans->state = TRANS_STATE_COMMIT_START;
2100 wake_up(&fs_info->transaction_blocked_wait);
2102 if (cur_trans->list.prev != &fs_info->trans_list) {
2103 prev_trans = list_entry(cur_trans->list.prev,
2104 struct btrfs_transaction, list);
2105 if (prev_trans->state != TRANS_STATE_COMPLETED) {
2106 refcount_inc(&prev_trans->use_count);
2107 spin_unlock(&fs_info->trans_lock);
2109 wait_for_commit(prev_trans);
2110 ret = prev_trans->aborted;
2112 btrfs_put_transaction(prev_trans);
2114 goto cleanup_transaction;
2116 spin_unlock(&fs_info->trans_lock);
2119 spin_unlock(&fs_info->trans_lock);
2121 * The previous transaction was aborted and was already removed
2122 * from the list of transactions at fs_info->trans_list. So we
2123 * abort to prevent writing a new superblock that reflects a
2124 * corrupt state (pointing to trees with unwritten nodes/leafs).
2126 if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state)) {
2128 goto cleanup_transaction;
2132 extwriter_counter_dec(cur_trans, trans->type);
2134 ret = btrfs_start_delalloc_flush(trans);
2136 goto cleanup_transaction;
2138 ret = btrfs_run_delayed_items(trans);
2140 goto cleanup_transaction;
2142 wait_event(cur_trans->writer_wait,
2143 extwriter_counter_read(cur_trans) == 0);
2145 /* some pending stuffs might be added after the previous flush. */
2146 ret = btrfs_run_delayed_items(trans);
2148 goto cleanup_transaction;
2150 btrfs_wait_delalloc_flush(trans);
2152 btrfs_scrub_pause(fs_info);
2154 * Ok now we need to make sure to block out any other joins while we
2155 * commit the transaction. We could have started a join before setting
2156 * COMMIT_DOING so make sure to wait for num_writers to == 1 again.
2158 spin_lock(&fs_info->trans_lock);
2159 cur_trans->state = TRANS_STATE_COMMIT_DOING;
2160 spin_unlock(&fs_info->trans_lock);
2161 wait_event(cur_trans->writer_wait,
2162 atomic_read(&cur_trans->num_writers) == 1);
2164 /* ->aborted might be set after the previous check, so check it */
2165 if (unlikely(READ_ONCE(cur_trans->aborted))) {
2166 ret = cur_trans->aborted;
2167 goto scrub_continue;
2170 * the reloc mutex makes sure that we stop
2171 * the balancing code from coming in and moving
2172 * extents around in the middle of the commit
2174 mutex_lock(&fs_info->reloc_mutex);
2177 * We needn't worry about the delayed items because we will
2178 * deal with them in create_pending_snapshot(), which is the
2179 * core function of the snapshot creation.
2181 ret = create_pending_snapshots(trans);
2183 mutex_unlock(&fs_info->reloc_mutex);
2184 goto scrub_continue;
2188 * We insert the dir indexes of the snapshots and update the inode
2189 * of the snapshots' parents after the snapshot creation, so there
2190 * are some delayed items which are not dealt with. Now deal with
2193 * We needn't worry that this operation will corrupt the snapshots,
2194 * because all the tree which are snapshoted will be forced to COW
2195 * the nodes and leaves.
2197 ret = btrfs_run_delayed_items(trans);
2199 mutex_unlock(&fs_info->reloc_mutex);
2200 goto scrub_continue;
2203 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
2205 mutex_unlock(&fs_info->reloc_mutex);
2206 goto scrub_continue;
2210 * make sure none of the code above managed to slip in a
2213 btrfs_assert_delayed_root_empty(fs_info);
2215 WARN_ON(cur_trans != trans->transaction);
2217 /* btrfs_commit_tree_roots is responsible for getting the
2218 * various roots consistent with each other. Every pointer
2219 * in the tree of tree roots has to point to the most up to date
2220 * root for every subvolume and other tree. So, we have to keep
2221 * the tree logging code from jumping in and changing any
2224 * At this point in the commit, there can't be any tree-log
2225 * writers, but a little lower down we drop the trans mutex
2226 * and let new people in. By holding the tree_log_mutex
2227 * from now until after the super is written, we avoid races
2228 * with the tree-log code.
2230 mutex_lock(&fs_info->tree_log_mutex);
2232 ret = commit_fs_roots(trans);
2234 mutex_unlock(&fs_info->tree_log_mutex);
2235 mutex_unlock(&fs_info->reloc_mutex);
2236 goto scrub_continue;
2240 * Since the transaction is done, we can apply the pending changes
2241 * before the next transaction.
2243 btrfs_apply_pending_changes(fs_info);
2245 /* commit_fs_roots gets rid of all the tree log roots, it is now
2246 * safe to free the root of tree log roots
2248 btrfs_free_log_root_tree(trans, fs_info);
2251 * commit_fs_roots() can call btrfs_save_ino_cache(), which generates
2252 * new delayed refs. Must handle them or qgroup can be wrong.
2254 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
2256 mutex_unlock(&fs_info->tree_log_mutex);
2257 mutex_unlock(&fs_info->reloc_mutex);
2258 goto scrub_continue;
2262 * Since fs roots are all committed, we can get a quite accurate
2263 * new_roots. So let's do quota accounting.
2265 ret = btrfs_qgroup_account_extents(trans);
2267 mutex_unlock(&fs_info->tree_log_mutex);
2268 mutex_unlock(&fs_info->reloc_mutex);
2269 goto scrub_continue;
2272 ret = commit_cowonly_roots(trans);
2274 mutex_unlock(&fs_info->tree_log_mutex);
2275 mutex_unlock(&fs_info->reloc_mutex);
2276 goto scrub_continue;
2280 * The tasks which save the space cache and inode cache may also
2281 * update ->aborted, check it.
2283 if (unlikely(READ_ONCE(cur_trans->aborted))) {
2284 ret = cur_trans->aborted;
2285 mutex_unlock(&fs_info->tree_log_mutex);
2286 mutex_unlock(&fs_info->reloc_mutex);
2287 goto scrub_continue;
2290 btrfs_prepare_extent_commit(fs_info);
2292 cur_trans = fs_info->running_transaction;
2294 btrfs_set_root_node(&fs_info->tree_root->root_item,
2295 fs_info->tree_root->node);
2296 list_add_tail(&fs_info->tree_root->dirty_list,
2297 &cur_trans->switch_commits);
2299 btrfs_set_root_node(&fs_info->chunk_root->root_item,
2300 fs_info->chunk_root->node);
2301 list_add_tail(&fs_info->chunk_root->dirty_list,
2302 &cur_trans->switch_commits);
2304 switch_commit_roots(cur_trans);
2306 ASSERT(list_empty(&cur_trans->dirty_bgs));
2307 ASSERT(list_empty(&cur_trans->io_bgs));
2308 update_super_roots(fs_info);
2310 btrfs_set_super_log_root(fs_info->super_copy, 0);
2311 btrfs_set_super_log_root_level(fs_info->super_copy, 0);
2312 memcpy(fs_info->super_for_commit, fs_info->super_copy,
2313 sizeof(*fs_info->super_copy));
2315 btrfs_commit_device_sizes(cur_trans);
2317 clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags);
2318 clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags);
2320 btrfs_trans_release_chunk_metadata(trans);
2322 spin_lock(&fs_info->trans_lock);
2323 cur_trans->state = TRANS_STATE_UNBLOCKED;
2324 fs_info->running_transaction = NULL;
2325 spin_unlock(&fs_info->trans_lock);
2326 mutex_unlock(&fs_info->reloc_mutex);
2328 wake_up(&fs_info->transaction_wait);
2330 ret = btrfs_write_and_wait_transaction(trans);
2332 btrfs_handle_fs_error(fs_info, ret,
2333 "Error while writing out transaction");
2334 mutex_unlock(&fs_info->tree_log_mutex);
2335 goto scrub_continue;
2338 ret = write_all_supers(fs_info, 0);
2340 * the super is written, we can safely allow the tree-loggers
2341 * to go about their business
2343 mutex_unlock(&fs_info->tree_log_mutex);
2345 goto scrub_continue;
2347 btrfs_finish_extent_commit(trans);
2349 if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &cur_trans->flags))
2350 btrfs_clear_space_info_full(fs_info);
2352 fs_info->last_trans_committed = cur_trans->transid;
2354 * We needn't acquire the lock here because there is no other task
2355 * which can change it.
2357 cur_trans->state = TRANS_STATE_COMPLETED;
2358 wake_up(&cur_trans->commit_wait);
2359 clear_bit(BTRFS_FS_NEED_ASYNC_COMMIT, &fs_info->flags);
2361 spin_lock(&fs_info->trans_lock);
2362 list_del_init(&cur_trans->list);
2363 spin_unlock(&fs_info->trans_lock);
2365 btrfs_put_transaction(cur_trans);
2366 btrfs_put_transaction(cur_trans);
2368 if (trans->type & __TRANS_FREEZABLE)
2369 sb_end_intwrite(fs_info->sb);
2371 trace_btrfs_transaction_commit(trans->root);
2373 btrfs_scrub_continue(fs_info);
2375 if (current->journal_info == trans)
2376 current->journal_info = NULL;
2378 kmem_cache_free(btrfs_trans_handle_cachep, trans);
2383 btrfs_scrub_continue(fs_info);
2384 cleanup_transaction:
2385 btrfs_trans_release_metadata(trans);
2386 btrfs_cleanup_pending_block_groups(trans);
2387 btrfs_trans_release_chunk_metadata(trans);
2388 trans->block_rsv = NULL;
2389 btrfs_warn(fs_info, "Skipping commit of aborted transaction.");
2390 if (current->journal_info == trans)
2391 current->journal_info = NULL;
2392 cleanup_transaction(trans, ret);
2398 * return < 0 if error
2399 * 0 if there are no more dead_roots at the time of call
2400 * 1 there are more to be processed, call me again
2402 * The return value indicates there are certainly more snapshots to delete, but
2403 * if there comes a new one during processing, it may return 0. We don't mind,
2404 * because btrfs_commit_super will poke cleaner thread and it will process it a
2405 * few seconds later.
2407 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root)
2410 struct btrfs_fs_info *fs_info = root->fs_info;
2412 spin_lock(&fs_info->trans_lock);
2413 if (list_empty(&fs_info->dead_roots)) {
2414 spin_unlock(&fs_info->trans_lock);
2417 root = list_first_entry(&fs_info->dead_roots,
2418 struct btrfs_root, root_list);
2419 list_del_init(&root->root_list);
2420 spin_unlock(&fs_info->trans_lock);
2422 btrfs_debug(fs_info, "cleaner removing %llu", root->root_key.objectid);
2424 btrfs_kill_all_delayed_nodes(root);
2426 if (btrfs_header_backref_rev(root->node) <
2427 BTRFS_MIXED_BACKREF_REV)
2428 ret = btrfs_drop_snapshot(root, NULL, 0, 0);
2430 ret = btrfs_drop_snapshot(root, NULL, 1, 0);
2432 return (ret < 0) ? 0 : 1;
2435 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info)
2440 prev = xchg(&fs_info->pending_changes, 0);
2444 bit = 1 << BTRFS_PENDING_SET_INODE_MAP_CACHE;
2446 btrfs_set_opt(fs_info->mount_opt, INODE_MAP_CACHE);
2449 bit = 1 << BTRFS_PENDING_CLEAR_INODE_MAP_CACHE;
2451 btrfs_clear_opt(fs_info->mount_opt, INODE_MAP_CACHE);
2454 bit = 1 << BTRFS_PENDING_COMMIT;
2456 btrfs_debug(fs_info, "pending commit done");
2461 "unknown pending changes left 0x%lx, ignoring", prev);