2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include <linux/slab.h>
21 #include <linux/sched.h>
22 #include <linux/writeback.h>
23 #include <linux/pagemap.h>
24 #include <linux/blkdev.h>
25 #include <linux/uuid.h>
28 #include "transaction.h"
31 #include "inode-map.h"
33 #include "dev-replace.h"
35 #define BTRFS_ROOT_TRANS_TAG 0
37 void put_transaction(struct btrfs_transaction *transaction)
39 WARN_ON(atomic_read(&transaction->use_count) == 0);
40 if (atomic_dec_and_test(&transaction->use_count)) {
41 BUG_ON(!list_empty(&transaction->list));
42 WARN_ON(transaction->delayed_refs.root.rb_node);
43 memset(transaction, 0, sizeof(*transaction));
44 kmem_cache_free(btrfs_transaction_cachep, transaction);
48 static noinline void switch_commit_root(struct btrfs_root *root)
50 free_extent_buffer(root->commit_root);
51 root->commit_root = btrfs_root_node(root);
55 * either allocate a new transaction or hop into the existing one
57 static noinline int join_transaction(struct btrfs_root *root, int type)
59 struct btrfs_transaction *cur_trans;
60 struct btrfs_fs_info *fs_info = root->fs_info;
62 spin_lock(&fs_info->trans_lock);
64 /* The file system has been taken offline. No new transactions. */
65 if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
66 spin_unlock(&fs_info->trans_lock);
70 if (fs_info->trans_no_join) {
72 * If we are JOIN_NOLOCK we're already committing a current
73 * transaction, we just need a handle to deal with something
74 * when committing the transaction, such as inode cache and
75 * space cache. It is a special case.
77 if (type != TRANS_JOIN_NOLOCK) {
78 spin_unlock(&fs_info->trans_lock);
83 cur_trans = fs_info->running_transaction;
85 if (cur_trans->aborted) {
86 spin_unlock(&fs_info->trans_lock);
87 return cur_trans->aborted;
89 atomic_inc(&cur_trans->use_count);
90 atomic_inc(&cur_trans->num_writers);
91 cur_trans->num_joined++;
92 spin_unlock(&fs_info->trans_lock);
95 spin_unlock(&fs_info->trans_lock);
98 * If we are ATTACH, we just want to catch the current transaction,
99 * and commit it. If there is no transaction, just return ENOENT.
101 if (type == TRANS_ATTACH)
104 cur_trans = kmem_cache_alloc(btrfs_transaction_cachep, GFP_NOFS);
108 spin_lock(&fs_info->trans_lock);
109 if (fs_info->running_transaction) {
111 * someone started a transaction after we unlocked. Make sure
112 * to redo the trans_no_join checks above
114 kmem_cache_free(btrfs_transaction_cachep, cur_trans);
116 } else if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
117 spin_unlock(&fs_info->trans_lock);
118 kmem_cache_free(btrfs_transaction_cachep, cur_trans);
122 atomic_set(&cur_trans->num_writers, 1);
123 cur_trans->num_joined = 0;
124 init_waitqueue_head(&cur_trans->writer_wait);
125 init_waitqueue_head(&cur_trans->commit_wait);
126 cur_trans->in_commit = 0;
127 cur_trans->blocked = 0;
129 * One for this trans handle, one so it will live on until we
130 * commit the transaction.
132 atomic_set(&cur_trans->use_count, 2);
133 cur_trans->commit_done = 0;
134 cur_trans->start_time = get_seconds();
136 cur_trans->delayed_refs.root = RB_ROOT;
137 cur_trans->delayed_refs.num_entries = 0;
138 cur_trans->delayed_refs.num_heads_ready = 0;
139 cur_trans->delayed_refs.num_heads = 0;
140 cur_trans->delayed_refs.flushing = 0;
141 cur_trans->delayed_refs.run_delayed_start = 0;
144 * although the tree mod log is per file system and not per transaction,
145 * the log must never go across transaction boundaries.
148 if (!list_empty(&fs_info->tree_mod_seq_list))
149 WARN(1, KERN_ERR "btrfs: tree_mod_seq_list not empty when "
150 "creating a fresh transaction\n");
151 if (!RB_EMPTY_ROOT(&fs_info->tree_mod_log))
152 WARN(1, KERN_ERR "btrfs: tree_mod_log rb tree not empty when "
153 "creating a fresh transaction\n");
154 atomic_set(&fs_info->tree_mod_seq, 0);
156 spin_lock_init(&cur_trans->commit_lock);
157 spin_lock_init(&cur_trans->delayed_refs.lock);
159 INIT_LIST_HEAD(&cur_trans->pending_snapshots);
160 list_add_tail(&cur_trans->list, &fs_info->trans_list);
161 extent_io_tree_init(&cur_trans->dirty_pages,
162 fs_info->btree_inode->i_mapping);
163 fs_info->generation++;
164 cur_trans->transid = fs_info->generation;
165 fs_info->running_transaction = cur_trans;
166 cur_trans->aborted = 0;
167 spin_unlock(&fs_info->trans_lock);
173 * this does all the record keeping required to make sure that a reference
174 * counted root is properly recorded in a given transaction. This is required
175 * to make sure the old root from before we joined the transaction is deleted
176 * when the transaction commits
178 static int record_root_in_trans(struct btrfs_trans_handle *trans,
179 struct btrfs_root *root)
181 if (root->ref_cows && root->last_trans < trans->transid) {
182 WARN_ON(root == root->fs_info->extent_root);
183 WARN_ON(root->commit_root != root->node);
186 * see below for in_trans_setup usage rules
187 * we have the reloc mutex held now, so there
188 * is only one writer in this function
190 root->in_trans_setup = 1;
192 /* make sure readers find in_trans_setup before
193 * they find our root->last_trans update
197 spin_lock(&root->fs_info->fs_roots_radix_lock);
198 if (root->last_trans == trans->transid) {
199 spin_unlock(&root->fs_info->fs_roots_radix_lock);
202 radix_tree_tag_set(&root->fs_info->fs_roots_radix,
203 (unsigned long)root->root_key.objectid,
204 BTRFS_ROOT_TRANS_TAG);
205 spin_unlock(&root->fs_info->fs_roots_radix_lock);
206 root->last_trans = trans->transid;
208 /* this is pretty tricky. We don't want to
209 * take the relocation lock in btrfs_record_root_in_trans
210 * unless we're really doing the first setup for this root in
213 * Normally we'd use root->last_trans as a flag to decide
214 * if we want to take the expensive mutex.
216 * But, we have to set root->last_trans before we
217 * init the relocation root, otherwise, we trip over warnings
218 * in ctree.c. The solution used here is to flag ourselves
219 * with root->in_trans_setup. When this is 1, we're still
220 * fixing up the reloc trees and everyone must wait.
222 * When this is zero, they can trust root->last_trans and fly
223 * through btrfs_record_root_in_trans without having to take the
224 * lock. smp_wmb() makes sure that all the writes above are
225 * done before we pop in the zero below
227 btrfs_init_reloc_root(trans, root);
229 root->in_trans_setup = 0;
235 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
236 struct btrfs_root *root)
242 * see record_root_in_trans for comments about in_trans_setup usage
246 if (root->last_trans == trans->transid &&
247 !root->in_trans_setup)
250 mutex_lock(&root->fs_info->reloc_mutex);
251 record_root_in_trans(trans, root);
252 mutex_unlock(&root->fs_info->reloc_mutex);
257 /* wait for commit against the current transaction to become unblocked
258 * when this is done, it is safe to start a new transaction, but the current
259 * transaction might not be fully on disk.
261 static void wait_current_trans(struct btrfs_root *root)
263 struct btrfs_transaction *cur_trans;
265 spin_lock(&root->fs_info->trans_lock);
266 cur_trans = root->fs_info->running_transaction;
267 if (cur_trans && cur_trans->blocked) {
268 atomic_inc(&cur_trans->use_count);
269 spin_unlock(&root->fs_info->trans_lock);
271 wait_event(root->fs_info->transaction_wait,
272 !cur_trans->blocked);
273 put_transaction(cur_trans);
275 spin_unlock(&root->fs_info->trans_lock);
279 static int may_wait_transaction(struct btrfs_root *root, int type)
281 if (root->fs_info->log_root_recovering)
284 if (type == TRANS_USERSPACE)
287 if (type == TRANS_START &&
288 !atomic_read(&root->fs_info->open_ioctl_trans))
294 static struct btrfs_trans_handle *
295 start_transaction(struct btrfs_root *root, u64 num_items, int type,
296 enum btrfs_reserve_flush_enum flush)
298 struct btrfs_trans_handle *h;
299 struct btrfs_transaction *cur_trans;
302 u64 qgroup_reserved = 0;
304 if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
305 return ERR_PTR(-EROFS);
307 if (current->journal_info) {
308 WARN_ON(type != TRANS_JOIN && type != TRANS_JOIN_NOLOCK);
309 h = current->journal_info;
311 WARN_ON(h->use_count > 2);
312 h->orig_rsv = h->block_rsv;
318 * Do the reservation before we join the transaction so we can do all
319 * the appropriate flushing if need be.
321 if (num_items > 0 && root != root->fs_info->chunk_root) {
322 if (root->fs_info->quota_enabled &&
323 is_fstree(root->root_key.objectid)) {
324 qgroup_reserved = num_items * root->leafsize;
325 ret = btrfs_qgroup_reserve(root, qgroup_reserved);
330 num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
331 ret = btrfs_block_rsv_add(root,
332 &root->fs_info->trans_block_rsv,
338 h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
345 * If we are JOIN_NOLOCK we're already committing a transaction and
346 * waiting on this guy, so we don't need to do the sb_start_intwrite
347 * because we're already holding a ref. We need this because we could
348 * have raced in and did an fsync() on a file which can kick a commit
349 * and then we deadlock with somebody doing a freeze.
351 * If we are ATTACH, it means we just want to catch the current
352 * transaction and commit it, so we needn't do sb_start_intwrite().
354 if (type < TRANS_JOIN_NOLOCK)
355 sb_start_intwrite(root->fs_info->sb);
357 if (may_wait_transaction(root, type))
358 wait_current_trans(root);
361 ret = join_transaction(root, type);
363 wait_current_trans(root);
364 } while (ret == -EBUSY);
367 /* We must get the transaction if we are JOIN_NOLOCK. */
368 BUG_ON(type == TRANS_JOIN_NOLOCK);
372 cur_trans = root->fs_info->running_transaction;
374 h->transid = cur_trans->transid;
375 h->transaction = cur_trans;
377 h->bytes_reserved = 0;
379 h->delayed_ref_updates = 0;
385 h->qgroup_reserved = qgroup_reserved;
386 h->delayed_ref_elem.seq = 0;
388 INIT_LIST_HEAD(&h->qgroup_ref_list);
389 INIT_LIST_HEAD(&h->new_bgs);
392 if (cur_trans->blocked && may_wait_transaction(root, type)) {
393 btrfs_commit_transaction(h, root);
398 trace_btrfs_space_reservation(root->fs_info, "transaction",
399 h->transid, num_bytes, 1);
400 h->block_rsv = &root->fs_info->trans_block_rsv;
401 h->bytes_reserved = num_bytes;
405 btrfs_record_root_in_trans(h, root);
407 if (!current->journal_info && type != TRANS_USERSPACE)
408 current->journal_info = h;
412 if (type < TRANS_JOIN_NOLOCK)
413 sb_end_intwrite(root->fs_info->sb);
414 kmem_cache_free(btrfs_trans_handle_cachep, h);
417 btrfs_block_rsv_release(root, &root->fs_info->trans_block_rsv,
421 btrfs_qgroup_free(root, qgroup_reserved);
425 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
428 return start_transaction(root, num_items, TRANS_START,
429 BTRFS_RESERVE_FLUSH_ALL);
432 struct btrfs_trans_handle *btrfs_start_transaction_lflush(
433 struct btrfs_root *root, int num_items)
435 return start_transaction(root, num_items, TRANS_START,
436 BTRFS_RESERVE_FLUSH_LIMIT);
439 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root)
441 return start_transaction(root, 0, TRANS_JOIN, 0);
444 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root)
446 return start_transaction(root, 0, TRANS_JOIN_NOLOCK, 0);
449 struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root)
451 return start_transaction(root, 0, TRANS_USERSPACE, 0);
454 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root)
456 return start_transaction(root, 0, TRANS_ATTACH, 0);
459 /* wait for a transaction commit to be fully complete */
460 static noinline void wait_for_commit(struct btrfs_root *root,
461 struct btrfs_transaction *commit)
463 wait_event(commit->commit_wait, commit->commit_done);
466 int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid)
468 struct btrfs_transaction *cur_trans = NULL, *t;
472 if (transid <= root->fs_info->last_trans_committed)
476 /* find specified transaction */
477 spin_lock(&root->fs_info->trans_lock);
478 list_for_each_entry(t, &root->fs_info->trans_list, list) {
479 if (t->transid == transid) {
481 atomic_inc(&cur_trans->use_count);
485 if (t->transid > transid) {
490 spin_unlock(&root->fs_info->trans_lock);
491 /* The specified transaction doesn't exist */
495 /* find newest transaction that is committing | committed */
496 spin_lock(&root->fs_info->trans_lock);
497 list_for_each_entry_reverse(t, &root->fs_info->trans_list,
503 atomic_inc(&cur_trans->use_count);
507 spin_unlock(&root->fs_info->trans_lock);
509 goto out; /* nothing committing|committed */
512 wait_for_commit(root, cur_trans);
513 put_transaction(cur_trans);
518 void btrfs_throttle(struct btrfs_root *root)
520 if (!atomic_read(&root->fs_info->open_ioctl_trans))
521 wait_current_trans(root);
524 static int should_end_transaction(struct btrfs_trans_handle *trans,
525 struct btrfs_root *root)
529 ret = btrfs_block_rsv_check(root, &root->fs_info->global_block_rsv, 5);
533 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
534 struct btrfs_root *root)
536 struct btrfs_transaction *cur_trans = trans->transaction;
541 if (cur_trans->blocked || cur_trans->delayed_refs.flushing)
544 updates = trans->delayed_ref_updates;
545 trans->delayed_ref_updates = 0;
547 err = btrfs_run_delayed_refs(trans, root, updates);
548 if (err) /* Error code will also eval true */
552 return should_end_transaction(trans, root);
555 static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
556 struct btrfs_root *root, int throttle)
558 struct btrfs_transaction *cur_trans = trans->transaction;
559 struct btrfs_fs_info *info = root->fs_info;
561 int lock = (trans->type != TRANS_JOIN_NOLOCK);
564 if (--trans->use_count) {
565 trans->block_rsv = trans->orig_rsv;
570 * do the qgroup accounting as early as possible
572 err = btrfs_delayed_refs_qgroup_accounting(trans, info);
574 btrfs_trans_release_metadata(trans, root);
575 trans->block_rsv = NULL;
577 * the same root has to be passed to start_transaction and
578 * end_transaction. Subvolume quota depends on this.
580 WARN_ON(trans->root != root);
582 if (trans->qgroup_reserved) {
583 btrfs_qgroup_free(root, trans->qgroup_reserved);
584 trans->qgroup_reserved = 0;
587 if (!list_empty(&trans->new_bgs))
588 btrfs_create_pending_block_groups(trans, root);
591 unsigned long cur = trans->delayed_ref_updates;
592 trans->delayed_ref_updates = 0;
594 trans->transaction->delayed_refs.num_heads_ready > 64) {
595 trans->delayed_ref_updates = 0;
596 btrfs_run_delayed_refs(trans, root, cur);
602 btrfs_trans_release_metadata(trans, root);
603 trans->block_rsv = NULL;
605 if (!list_empty(&trans->new_bgs))
606 btrfs_create_pending_block_groups(trans, root);
608 if (lock && !atomic_read(&root->fs_info->open_ioctl_trans) &&
609 should_end_transaction(trans, root)) {
610 trans->transaction->blocked = 1;
614 if (lock && cur_trans->blocked && !cur_trans->in_commit) {
617 * We may race with somebody else here so end up having
618 * to call end_transaction on ourselves again, so inc
622 return btrfs_commit_transaction(trans, root);
624 wake_up_process(info->transaction_kthread);
628 if (trans->type < TRANS_JOIN_NOLOCK)
629 sb_end_intwrite(root->fs_info->sb);
631 WARN_ON(cur_trans != info->running_transaction);
632 WARN_ON(atomic_read(&cur_trans->num_writers) < 1);
633 atomic_dec(&cur_trans->num_writers);
636 if (waitqueue_active(&cur_trans->writer_wait))
637 wake_up(&cur_trans->writer_wait);
638 put_transaction(cur_trans);
640 if (current->journal_info == trans)
641 current->journal_info = NULL;
644 btrfs_run_delayed_iputs(root);
646 if (trans->aborted ||
647 root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
650 assert_qgroups_uptodate(trans);
652 memset(trans, 0, sizeof(*trans));
653 kmem_cache_free(btrfs_trans_handle_cachep, trans);
657 int btrfs_end_transaction(struct btrfs_trans_handle *trans,
658 struct btrfs_root *root)
662 ret = __btrfs_end_transaction(trans, root, 0);
668 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans,
669 struct btrfs_root *root)
673 ret = __btrfs_end_transaction(trans, root, 1);
679 int btrfs_end_transaction_dmeta(struct btrfs_trans_handle *trans,
680 struct btrfs_root *root)
682 return __btrfs_end_transaction(trans, root, 1);
686 * when btree blocks are allocated, they have some corresponding bits set for
687 * them in one of two extent_io trees. This is used to make sure all of
688 * those extents are sent to disk but does not wait on them
690 int btrfs_write_marked_extents(struct btrfs_root *root,
691 struct extent_io_tree *dirty_pages, int mark)
695 struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
696 struct extent_state *cached_state = NULL;
700 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
701 mark, &cached_state)) {
702 convert_extent_bit(dirty_pages, start, end, EXTENT_NEED_WAIT,
703 mark, &cached_state, GFP_NOFS);
705 err = filemap_fdatawrite_range(mapping, start, end);
717 * when btree blocks are allocated, they have some corresponding bits set for
718 * them in one of two extent_io trees. This is used to make sure all of
719 * those extents are on disk for transaction or log commit. We wait
720 * on all the pages and clear them from the dirty pages state tree
722 int btrfs_wait_marked_extents(struct btrfs_root *root,
723 struct extent_io_tree *dirty_pages, int mark)
727 struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
728 struct extent_state *cached_state = NULL;
732 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
733 EXTENT_NEED_WAIT, &cached_state)) {
734 clear_extent_bit(dirty_pages, start, end, EXTENT_NEED_WAIT,
735 0, 0, &cached_state, GFP_NOFS);
736 err = filemap_fdatawait_range(mapping, start, end);
748 * when btree blocks are allocated, they have some corresponding bits set for
749 * them in one of two extent_io trees. This is used to make sure all of
750 * those extents are on disk for transaction or log commit
752 int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
753 struct extent_io_tree *dirty_pages, int mark)
758 ret = btrfs_write_marked_extents(root, dirty_pages, mark);
759 ret2 = btrfs_wait_marked_extents(root, dirty_pages, mark);
768 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
769 struct btrfs_root *root)
771 if (!trans || !trans->transaction) {
772 struct inode *btree_inode;
773 btree_inode = root->fs_info->btree_inode;
774 return filemap_write_and_wait(btree_inode->i_mapping);
776 return btrfs_write_and_wait_marked_extents(root,
777 &trans->transaction->dirty_pages,
782 * this is used to update the root pointer in the tree of tree roots.
784 * But, in the case of the extent allocation tree, updating the root
785 * pointer may allocate blocks which may change the root of the extent
788 * So, this loops and repeats and makes sure the cowonly root didn't
789 * change while the root pointer was being updated in the metadata.
791 static int update_cowonly_root(struct btrfs_trans_handle *trans,
792 struct btrfs_root *root)
797 struct btrfs_root *tree_root = root->fs_info->tree_root;
799 old_root_used = btrfs_root_used(&root->root_item);
800 btrfs_write_dirty_block_groups(trans, root);
803 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
804 if (old_root_bytenr == root->node->start &&
805 old_root_used == btrfs_root_used(&root->root_item))
808 btrfs_set_root_node(&root->root_item, root->node);
809 ret = btrfs_update_root(trans, tree_root,
815 old_root_used = btrfs_root_used(&root->root_item);
816 ret = btrfs_write_dirty_block_groups(trans, root);
821 if (root != root->fs_info->extent_root)
822 switch_commit_root(root);
828 * update all the cowonly tree roots on disk
830 * The error handling in this function may not be obvious. Any of the
831 * failures will cause the file system to go offline. We still need
832 * to clean up the delayed refs.
834 static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans,
835 struct btrfs_root *root)
837 struct btrfs_fs_info *fs_info = root->fs_info;
838 struct list_head *next;
839 struct extent_buffer *eb;
842 ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
846 eb = btrfs_lock_root_node(fs_info->tree_root);
847 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL,
849 btrfs_tree_unlock(eb);
850 free_extent_buffer(eb);
855 ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
859 ret = btrfs_run_dev_stats(trans, root->fs_info);
861 ret = btrfs_run_dev_replace(trans, root->fs_info);
864 ret = btrfs_run_qgroups(trans, root->fs_info);
867 /* run_qgroups might have added some more refs */
868 ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
871 while (!list_empty(&fs_info->dirty_cowonly_roots)) {
872 next = fs_info->dirty_cowonly_roots.next;
874 root = list_entry(next, struct btrfs_root, dirty_list);
876 ret = update_cowonly_root(trans, root);
881 down_write(&fs_info->extent_commit_sem);
882 switch_commit_root(fs_info->extent_root);
883 up_write(&fs_info->extent_commit_sem);
885 btrfs_after_dev_replace_commit(fs_info);
891 * dead roots are old snapshots that need to be deleted. This allocates
892 * a dirty root struct and adds it into the list of dead roots that need to
895 int btrfs_add_dead_root(struct btrfs_root *root)
897 spin_lock(&root->fs_info->trans_lock);
898 list_add(&root->root_list, &root->fs_info->dead_roots);
899 spin_unlock(&root->fs_info->trans_lock);
904 * update all the cowonly tree roots on disk
906 static noinline int commit_fs_roots(struct btrfs_trans_handle *trans,
907 struct btrfs_root *root)
909 struct btrfs_root *gang[8];
910 struct btrfs_fs_info *fs_info = root->fs_info;
915 spin_lock(&fs_info->fs_roots_radix_lock);
917 ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
920 BTRFS_ROOT_TRANS_TAG);
923 for (i = 0; i < ret; i++) {
925 radix_tree_tag_clear(&fs_info->fs_roots_radix,
926 (unsigned long)root->root_key.objectid,
927 BTRFS_ROOT_TRANS_TAG);
928 spin_unlock(&fs_info->fs_roots_radix_lock);
930 btrfs_free_log(trans, root);
931 btrfs_update_reloc_root(trans, root);
932 btrfs_orphan_commit_root(trans, root);
934 btrfs_save_ino_cache(root, trans);
936 /* see comments in should_cow_block() */
940 if (root->commit_root != root->node) {
941 mutex_lock(&root->fs_commit_mutex);
942 switch_commit_root(root);
943 btrfs_unpin_free_ino(root);
944 mutex_unlock(&root->fs_commit_mutex);
946 btrfs_set_root_node(&root->root_item,
950 err = btrfs_update_root(trans, fs_info->tree_root,
953 spin_lock(&fs_info->fs_roots_radix_lock);
958 spin_unlock(&fs_info->fs_roots_radix_lock);
963 * defrag a given btree. If cacheonly == 1, this won't read from the disk,
964 * otherwise every leaf in the btree is read and defragged.
966 int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
968 struct btrfs_fs_info *info = root->fs_info;
969 struct btrfs_trans_handle *trans;
972 if (xchg(&root->defrag_running, 1))
976 trans = btrfs_start_transaction(root, 0);
978 return PTR_ERR(trans);
980 ret = btrfs_defrag_leaves(trans, root, cacheonly);
982 btrfs_end_transaction(trans, root);
983 btrfs_btree_balance_dirty(info->tree_root);
986 if (btrfs_fs_closing(root->fs_info) || ret != -EAGAIN)
989 root->defrag_running = 0;
994 * new snapshots need to be created at a very specific time in the
995 * transaction commit. This does the actual creation
997 static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
998 struct btrfs_fs_info *fs_info,
999 struct btrfs_pending_snapshot *pending)
1001 struct btrfs_key key;
1002 struct btrfs_root_item *new_root_item;
1003 struct btrfs_root *tree_root = fs_info->tree_root;
1004 struct btrfs_root *root = pending->root;
1005 struct btrfs_root *parent_root;
1006 struct btrfs_block_rsv *rsv;
1007 struct inode *parent_inode;
1008 struct btrfs_path *path;
1009 struct btrfs_dir_item *dir_item;
1010 struct dentry *parent;
1011 struct dentry *dentry;
1012 struct extent_buffer *tmp;
1013 struct extent_buffer *old;
1014 struct timespec cur_time = CURRENT_TIME;
1022 path = btrfs_alloc_path();
1024 ret = pending->error = -ENOMEM;
1025 goto path_alloc_fail;
1028 new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
1029 if (!new_root_item) {
1030 ret = pending->error = -ENOMEM;
1031 goto root_item_alloc_fail;
1034 ret = btrfs_find_free_objectid(tree_root, &objectid);
1036 pending->error = ret;
1037 goto no_free_objectid;
1040 btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
1042 if (to_reserve > 0) {
1043 ret = btrfs_block_rsv_add(root, &pending->block_rsv,
1045 BTRFS_RESERVE_NO_FLUSH);
1047 pending->error = ret;
1048 goto no_free_objectid;
1052 ret = btrfs_qgroup_inherit(trans, fs_info, root->root_key.objectid,
1053 objectid, pending->inherit);
1055 pending->error = ret;
1056 goto no_free_objectid;
1059 key.objectid = objectid;
1060 key.offset = (u64)-1;
1061 key.type = BTRFS_ROOT_ITEM_KEY;
1063 rsv = trans->block_rsv;
1064 trans->block_rsv = &pending->block_rsv;
1066 dentry = pending->dentry;
1067 parent = dget_parent(dentry);
1068 parent_inode = parent->d_inode;
1069 parent_root = BTRFS_I(parent_inode)->root;
1070 record_root_in_trans(trans, parent_root);
1073 * insert the directory item
1075 ret = btrfs_set_inode_index(parent_inode, &index);
1076 BUG_ON(ret); /* -ENOMEM */
1078 /* check if there is a file/dir which has the same name. */
1079 dir_item = btrfs_lookup_dir_item(NULL, parent_root, path,
1080 btrfs_ino(parent_inode),
1081 dentry->d_name.name,
1082 dentry->d_name.len, 0);
1083 if (dir_item != NULL && !IS_ERR(dir_item)) {
1084 pending->error = -EEXIST;
1086 } else if (IS_ERR(dir_item)) {
1087 ret = PTR_ERR(dir_item);
1088 btrfs_abort_transaction(trans, root, ret);
1091 btrfs_release_path(path);
1094 * pull in the delayed directory update
1095 * and the delayed inode item
1096 * otherwise we corrupt the FS during
1099 ret = btrfs_run_delayed_items(trans, root);
1100 if (ret) { /* Transaction aborted */
1101 btrfs_abort_transaction(trans, root, ret);
1105 record_root_in_trans(trans, root);
1106 btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
1107 memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
1108 btrfs_check_and_init_root_item(new_root_item);
1110 root_flags = btrfs_root_flags(new_root_item);
1111 if (pending->readonly)
1112 root_flags |= BTRFS_ROOT_SUBVOL_RDONLY;
1114 root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY;
1115 btrfs_set_root_flags(new_root_item, root_flags);
1117 btrfs_set_root_generation_v2(new_root_item,
1119 uuid_le_gen(&new_uuid);
1120 memcpy(new_root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
1121 memcpy(new_root_item->parent_uuid, root->root_item.uuid,
1123 new_root_item->otime.sec = cpu_to_le64(cur_time.tv_sec);
1124 new_root_item->otime.nsec = cpu_to_le32(cur_time.tv_nsec);
1125 btrfs_set_root_otransid(new_root_item, trans->transid);
1126 memset(&new_root_item->stime, 0, sizeof(new_root_item->stime));
1127 memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime));
1128 btrfs_set_root_stransid(new_root_item, 0);
1129 btrfs_set_root_rtransid(new_root_item, 0);
1131 old = btrfs_lock_root_node(root);
1132 ret = btrfs_cow_block(trans, root, old, NULL, 0, &old);
1134 btrfs_tree_unlock(old);
1135 free_extent_buffer(old);
1136 btrfs_abort_transaction(trans, root, ret);
1140 btrfs_set_lock_blocking(old);
1142 ret = btrfs_copy_root(trans, root, old, &tmp, objectid);
1143 /* clean up in any case */
1144 btrfs_tree_unlock(old);
1145 free_extent_buffer(old);
1147 btrfs_abort_transaction(trans, root, ret);
1151 /* see comments in should_cow_block() */
1152 root->force_cow = 1;
1155 btrfs_set_root_node(new_root_item, tmp);
1156 /* record when the snapshot was created in key.offset */
1157 key.offset = trans->transid;
1158 ret = btrfs_insert_root(trans, tree_root, &key, new_root_item);
1159 btrfs_tree_unlock(tmp);
1160 free_extent_buffer(tmp);
1162 btrfs_abort_transaction(trans, root, ret);
1167 * insert root back/forward references
1169 ret = btrfs_add_root_ref(trans, tree_root, objectid,
1170 parent_root->root_key.objectid,
1171 btrfs_ino(parent_inode), index,
1172 dentry->d_name.name, dentry->d_name.len);
1174 btrfs_abort_transaction(trans, root, ret);
1178 key.offset = (u64)-1;
1179 pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key);
1180 if (IS_ERR(pending->snap)) {
1181 ret = PTR_ERR(pending->snap);
1182 btrfs_abort_transaction(trans, root, ret);
1186 ret = btrfs_reloc_post_snapshot(trans, pending);
1188 btrfs_abort_transaction(trans, root, ret);
1192 ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
1194 btrfs_abort_transaction(trans, root, ret);
1198 ret = btrfs_insert_dir_item(trans, parent_root,
1199 dentry->d_name.name, dentry->d_name.len,
1201 BTRFS_FT_DIR, index);
1202 /* We have check then name at the beginning, so it is impossible. */
1203 BUG_ON(ret == -EEXIST || ret == -EOVERFLOW);
1205 btrfs_abort_transaction(trans, root, ret);
1209 btrfs_i_size_write(parent_inode, parent_inode->i_size +
1210 dentry->d_name.len * 2);
1211 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
1212 ret = btrfs_update_inode_fallback(trans, parent_root, parent_inode);
1214 btrfs_abort_transaction(trans, root, ret);
1217 trans->block_rsv = rsv;
1219 kfree(new_root_item);
1220 root_item_alloc_fail:
1221 btrfs_free_path(path);
1223 btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1);
1228 * create all the snapshots we've scheduled for creation
1230 static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans,
1231 struct btrfs_fs_info *fs_info)
1233 struct btrfs_pending_snapshot *pending;
1234 struct list_head *head = &trans->transaction->pending_snapshots;
1236 list_for_each_entry(pending, head, list)
1237 create_pending_snapshot(trans, fs_info, pending);
1241 static void update_super_roots(struct btrfs_root *root)
1243 struct btrfs_root_item *root_item;
1244 struct btrfs_super_block *super;
1246 super = root->fs_info->super_copy;
1248 root_item = &root->fs_info->chunk_root->root_item;
1249 super->chunk_root = root_item->bytenr;
1250 super->chunk_root_generation = root_item->generation;
1251 super->chunk_root_level = root_item->level;
1253 root_item = &root->fs_info->tree_root->root_item;
1254 super->root = root_item->bytenr;
1255 super->generation = root_item->generation;
1256 super->root_level = root_item->level;
1257 if (btrfs_test_opt(root, SPACE_CACHE))
1258 super->cache_generation = root_item->generation;
1261 int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
1264 spin_lock(&info->trans_lock);
1265 if (info->running_transaction)
1266 ret = info->running_transaction->in_commit;
1267 spin_unlock(&info->trans_lock);
1271 int btrfs_transaction_blocked(struct btrfs_fs_info *info)
1274 spin_lock(&info->trans_lock);
1275 if (info->running_transaction)
1276 ret = info->running_transaction->blocked;
1277 spin_unlock(&info->trans_lock);
1282 * wait for the current transaction commit to start and block subsequent
1285 static void wait_current_trans_commit_start(struct btrfs_root *root,
1286 struct btrfs_transaction *trans)
1288 wait_event(root->fs_info->transaction_blocked_wait, trans->in_commit);
1292 * wait for the current transaction to start and then become unblocked.
1295 static void wait_current_trans_commit_start_and_unblock(struct btrfs_root *root,
1296 struct btrfs_transaction *trans)
1298 wait_event(root->fs_info->transaction_wait,
1299 trans->commit_done || (trans->in_commit && !trans->blocked));
1303 * commit transactions asynchronously. once btrfs_commit_transaction_async
1304 * returns, any subsequent transaction will not be allowed to join.
1306 struct btrfs_async_commit {
1307 struct btrfs_trans_handle *newtrans;
1308 struct btrfs_root *root;
1309 struct delayed_work work;
1312 static void do_async_commit(struct work_struct *work)
1314 struct btrfs_async_commit *ac =
1315 container_of(work, struct btrfs_async_commit, work.work);
1318 * We've got freeze protection passed with the transaction.
1319 * Tell lockdep about it.
1321 if (ac->newtrans->type < TRANS_JOIN_NOLOCK)
1323 &ac->root->fs_info->sb->s_writers.lock_map[SB_FREEZE_FS-1],
1326 current->journal_info = ac->newtrans;
1328 btrfs_commit_transaction(ac->newtrans, ac->root);
1332 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
1333 struct btrfs_root *root,
1334 int wait_for_unblock)
1336 struct btrfs_async_commit *ac;
1337 struct btrfs_transaction *cur_trans;
1339 ac = kmalloc(sizeof(*ac), GFP_NOFS);
1343 INIT_DELAYED_WORK(&ac->work, do_async_commit);
1345 ac->newtrans = btrfs_join_transaction(root);
1346 if (IS_ERR(ac->newtrans)) {
1347 int err = PTR_ERR(ac->newtrans);
1352 /* take transaction reference */
1353 cur_trans = trans->transaction;
1354 atomic_inc(&cur_trans->use_count);
1356 btrfs_end_transaction(trans, root);
1359 * Tell lockdep we've released the freeze rwsem, since the
1360 * async commit thread will be the one to unlock it.
1362 if (trans->type < TRANS_JOIN_NOLOCK)
1364 &root->fs_info->sb->s_writers.lock_map[SB_FREEZE_FS-1],
1367 schedule_delayed_work(&ac->work, 0);
1369 /* wait for transaction to start and unblock */
1370 if (wait_for_unblock)
1371 wait_current_trans_commit_start_and_unblock(root, cur_trans);
1373 wait_current_trans_commit_start(root, cur_trans);
1375 if (current->journal_info == trans)
1376 current->journal_info = NULL;
1378 put_transaction(cur_trans);
1383 static void cleanup_transaction(struct btrfs_trans_handle *trans,
1384 struct btrfs_root *root, int err)
1386 struct btrfs_transaction *cur_trans = trans->transaction;
1388 WARN_ON(trans->use_count > 1);
1390 btrfs_abort_transaction(trans, root, err);
1392 spin_lock(&root->fs_info->trans_lock);
1393 list_del_init(&cur_trans->list);
1394 if (cur_trans == root->fs_info->running_transaction) {
1395 root->fs_info->running_transaction = NULL;
1396 root->fs_info->trans_no_join = 0;
1398 spin_unlock(&root->fs_info->trans_lock);
1400 btrfs_cleanup_one_transaction(trans->transaction, root);
1402 put_transaction(cur_trans);
1403 put_transaction(cur_trans);
1405 trace_btrfs_transaction_commit(root);
1407 btrfs_scrub_continue(root);
1409 if (current->journal_info == trans)
1410 current->journal_info = NULL;
1412 kmem_cache_free(btrfs_trans_handle_cachep, trans);
1415 static int btrfs_flush_all_pending_stuffs(struct btrfs_trans_handle *trans,
1416 struct btrfs_root *root)
1418 int flush_on_commit = btrfs_test_opt(root, FLUSHONCOMMIT);
1419 int snap_pending = 0;
1422 if (!flush_on_commit) {
1423 spin_lock(&root->fs_info->trans_lock);
1424 if (!list_empty(&trans->transaction->pending_snapshots))
1426 spin_unlock(&root->fs_info->trans_lock);
1429 if (flush_on_commit || snap_pending) {
1430 btrfs_start_delalloc_inodes(root, 1);
1431 btrfs_wait_ordered_extents(root, 1);
1434 ret = btrfs_run_delayed_items(trans, root);
1439 * running the delayed items may have added new refs. account
1440 * them now so that they hinder processing of more delayed refs
1441 * as little as possible.
1443 btrfs_delayed_refs_qgroup_accounting(trans, root->fs_info);
1446 * rename don't use btrfs_join_transaction, so, once we
1447 * set the transaction to blocked above, we aren't going
1448 * to get any new ordered operations. We can safely run
1449 * it here and no for sure that nothing new will be added
1452 btrfs_run_ordered_operations(root, 1);
1458 * btrfs_transaction state sequence:
1459 * in_commit = 0, blocked = 0 (initial)
1460 * in_commit = 1, blocked = 1
1464 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
1465 struct btrfs_root *root)
1467 unsigned long joined = 0;
1468 struct btrfs_transaction *cur_trans = trans->transaction;
1469 struct btrfs_transaction *prev_trans = NULL;
1472 int should_grow = 0;
1473 unsigned long now = get_seconds();
1475 ret = btrfs_run_ordered_operations(root, 0);
1477 btrfs_abort_transaction(trans, root, ret);
1478 goto cleanup_transaction;
1481 /* Stop the commit early if ->aborted is set */
1482 if (unlikely(ACCESS_ONCE(cur_trans->aborted))) {
1483 ret = cur_trans->aborted;
1484 goto cleanup_transaction;
1487 /* make a pass through all the delayed refs we have so far
1488 * any runnings procs may add more while we are here
1490 ret = btrfs_run_delayed_refs(trans, root, 0);
1492 goto cleanup_transaction;
1494 btrfs_trans_release_metadata(trans, root);
1495 trans->block_rsv = NULL;
1497 cur_trans = trans->transaction;
1500 * set the flushing flag so procs in this transaction have to
1501 * start sending their work down.
1503 cur_trans->delayed_refs.flushing = 1;
1505 if (!list_empty(&trans->new_bgs))
1506 btrfs_create_pending_block_groups(trans, root);
1508 ret = btrfs_run_delayed_refs(trans, root, 0);
1510 goto cleanup_transaction;
1512 spin_lock(&cur_trans->commit_lock);
1513 if (cur_trans->in_commit) {
1514 spin_unlock(&cur_trans->commit_lock);
1515 atomic_inc(&cur_trans->use_count);
1516 ret = btrfs_end_transaction(trans, root);
1518 wait_for_commit(root, cur_trans);
1520 put_transaction(cur_trans);
1525 trans->transaction->in_commit = 1;
1526 trans->transaction->blocked = 1;
1527 spin_unlock(&cur_trans->commit_lock);
1528 wake_up(&root->fs_info->transaction_blocked_wait);
1530 spin_lock(&root->fs_info->trans_lock);
1531 if (cur_trans->list.prev != &root->fs_info->trans_list) {
1532 prev_trans = list_entry(cur_trans->list.prev,
1533 struct btrfs_transaction, list);
1534 if (!prev_trans->commit_done) {
1535 atomic_inc(&prev_trans->use_count);
1536 spin_unlock(&root->fs_info->trans_lock);
1538 wait_for_commit(root, prev_trans);
1540 put_transaction(prev_trans);
1542 spin_unlock(&root->fs_info->trans_lock);
1545 spin_unlock(&root->fs_info->trans_lock);
1548 if (!btrfs_test_opt(root, SSD) &&
1549 (now < cur_trans->start_time || now - cur_trans->start_time < 1))
1553 joined = cur_trans->num_joined;
1555 WARN_ON(cur_trans != trans->transaction);
1557 ret = btrfs_flush_all_pending_stuffs(trans, root);
1559 goto cleanup_transaction;
1561 prepare_to_wait(&cur_trans->writer_wait, &wait,
1562 TASK_UNINTERRUPTIBLE);
1564 if (atomic_read(&cur_trans->num_writers) > 1)
1565 schedule_timeout(MAX_SCHEDULE_TIMEOUT);
1566 else if (should_grow)
1567 schedule_timeout(1);
1569 finish_wait(&cur_trans->writer_wait, &wait);
1570 } while (atomic_read(&cur_trans->num_writers) > 1 ||
1571 (should_grow && cur_trans->num_joined != joined));
1573 ret = btrfs_flush_all_pending_stuffs(trans, root);
1575 goto cleanup_transaction;
1578 * Ok now we need to make sure to block out any other joins while we
1579 * commit the transaction. We could have started a join before setting
1580 * no_join so make sure to wait for num_writers to == 1 again.
1582 spin_lock(&root->fs_info->trans_lock);
1583 root->fs_info->trans_no_join = 1;
1584 spin_unlock(&root->fs_info->trans_lock);
1585 wait_event(cur_trans->writer_wait,
1586 atomic_read(&cur_trans->num_writers) == 1);
1588 /* ->aborted might be set after the previous check, so check it */
1589 if (unlikely(ACCESS_ONCE(cur_trans->aborted))) {
1590 ret = cur_trans->aborted;
1591 goto cleanup_transaction;
1594 * the reloc mutex makes sure that we stop
1595 * the balancing code from coming in and moving
1596 * extents around in the middle of the commit
1598 mutex_lock(&root->fs_info->reloc_mutex);
1601 * We needn't worry about the delayed items because we will
1602 * deal with them in create_pending_snapshot(), which is the
1603 * core function of the snapshot creation.
1605 ret = create_pending_snapshots(trans, root->fs_info);
1607 mutex_unlock(&root->fs_info->reloc_mutex);
1608 goto cleanup_transaction;
1612 * We insert the dir indexes of the snapshots and update the inode
1613 * of the snapshots' parents after the snapshot creation, so there
1614 * are some delayed items which are not dealt with. Now deal with
1617 * We needn't worry that this operation will corrupt the snapshots,
1618 * because all the tree which are snapshoted will be forced to COW
1619 * the nodes and leaves.
1621 ret = btrfs_run_delayed_items(trans, root);
1623 mutex_unlock(&root->fs_info->reloc_mutex);
1624 goto cleanup_transaction;
1627 ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
1629 mutex_unlock(&root->fs_info->reloc_mutex);
1630 goto cleanup_transaction;
1634 * make sure none of the code above managed to slip in a
1637 btrfs_assert_delayed_root_empty(root);
1639 WARN_ON(cur_trans != trans->transaction);
1641 btrfs_scrub_pause(root);
1642 /* btrfs_commit_tree_roots is responsible for getting the
1643 * various roots consistent with each other. Every pointer
1644 * in the tree of tree roots has to point to the most up to date
1645 * root for every subvolume and other tree. So, we have to keep
1646 * the tree logging code from jumping in and changing any
1649 * At this point in the commit, there can't be any tree-log
1650 * writers, but a little lower down we drop the trans mutex
1651 * and let new people in. By holding the tree_log_mutex
1652 * from now until after the super is written, we avoid races
1653 * with the tree-log code.
1655 mutex_lock(&root->fs_info->tree_log_mutex);
1657 ret = commit_fs_roots(trans, root);
1659 mutex_unlock(&root->fs_info->tree_log_mutex);
1660 mutex_unlock(&root->fs_info->reloc_mutex);
1661 goto cleanup_transaction;
1664 /* commit_fs_roots gets rid of all the tree log roots, it is now
1665 * safe to free the root of tree log roots
1667 btrfs_free_log_root_tree(trans, root->fs_info);
1669 ret = commit_cowonly_roots(trans, root);
1671 mutex_unlock(&root->fs_info->tree_log_mutex);
1672 mutex_unlock(&root->fs_info->reloc_mutex);
1673 goto cleanup_transaction;
1677 * The tasks which save the space cache and inode cache may also
1678 * update ->aborted, check it.
1680 if (unlikely(ACCESS_ONCE(cur_trans->aborted))) {
1681 ret = cur_trans->aborted;
1682 mutex_unlock(&root->fs_info->tree_log_mutex);
1683 mutex_unlock(&root->fs_info->reloc_mutex);
1684 goto cleanup_transaction;
1687 btrfs_prepare_extent_commit(trans, root);
1689 cur_trans = root->fs_info->running_transaction;
1691 btrfs_set_root_node(&root->fs_info->tree_root->root_item,
1692 root->fs_info->tree_root->node);
1693 switch_commit_root(root->fs_info->tree_root);
1695 btrfs_set_root_node(&root->fs_info->chunk_root->root_item,
1696 root->fs_info->chunk_root->node);
1697 switch_commit_root(root->fs_info->chunk_root);
1699 assert_qgroups_uptodate(trans);
1700 update_super_roots(root);
1702 if (!root->fs_info->log_root_recovering) {
1703 btrfs_set_super_log_root(root->fs_info->super_copy, 0);
1704 btrfs_set_super_log_root_level(root->fs_info->super_copy, 0);
1707 memcpy(root->fs_info->super_for_commit, root->fs_info->super_copy,
1708 sizeof(*root->fs_info->super_copy));
1710 trans->transaction->blocked = 0;
1711 spin_lock(&root->fs_info->trans_lock);
1712 root->fs_info->running_transaction = NULL;
1713 root->fs_info->trans_no_join = 0;
1714 spin_unlock(&root->fs_info->trans_lock);
1715 mutex_unlock(&root->fs_info->reloc_mutex);
1717 wake_up(&root->fs_info->transaction_wait);
1719 ret = btrfs_write_and_wait_transaction(trans, root);
1721 btrfs_error(root->fs_info, ret,
1722 "Error while writing out transaction.");
1723 mutex_unlock(&root->fs_info->tree_log_mutex);
1724 goto cleanup_transaction;
1727 ret = write_ctree_super(trans, root, 0);
1729 mutex_unlock(&root->fs_info->tree_log_mutex);
1730 goto cleanup_transaction;
1734 * the super is written, we can safely allow the tree-loggers
1735 * to go about their business
1737 mutex_unlock(&root->fs_info->tree_log_mutex);
1739 btrfs_finish_extent_commit(trans, root);
1741 cur_trans->commit_done = 1;
1743 root->fs_info->last_trans_committed = cur_trans->transid;
1745 wake_up(&cur_trans->commit_wait);
1747 spin_lock(&root->fs_info->trans_lock);
1748 list_del_init(&cur_trans->list);
1749 spin_unlock(&root->fs_info->trans_lock);
1751 put_transaction(cur_trans);
1752 put_transaction(cur_trans);
1754 if (trans->type < TRANS_JOIN_NOLOCK)
1755 sb_end_intwrite(root->fs_info->sb);
1757 trace_btrfs_transaction_commit(root);
1759 btrfs_scrub_continue(root);
1761 if (current->journal_info == trans)
1762 current->journal_info = NULL;
1764 kmem_cache_free(btrfs_trans_handle_cachep, trans);
1766 if (current != root->fs_info->transaction_kthread)
1767 btrfs_run_delayed_iputs(root);
1771 cleanup_transaction:
1772 btrfs_trans_release_metadata(trans, root);
1773 trans->block_rsv = NULL;
1774 btrfs_printk(root->fs_info, "Skipping commit of aborted transaction.\n");
1776 if (current->journal_info == trans)
1777 current->journal_info = NULL;
1778 cleanup_transaction(trans, root, ret);
1784 * interface function to delete all the snapshots we have scheduled for deletion
1786 int btrfs_clean_old_snapshots(struct btrfs_root *root)
1789 struct btrfs_fs_info *fs_info = root->fs_info;
1791 spin_lock(&fs_info->trans_lock);
1792 list_splice_init(&fs_info->dead_roots, &list);
1793 spin_unlock(&fs_info->trans_lock);
1795 while (!list_empty(&list)) {
1798 root = list_entry(list.next, struct btrfs_root, root_list);
1799 list_del(&root->root_list);
1801 btrfs_kill_all_delayed_nodes(root);
1803 if (btrfs_header_backref_rev(root->node) <
1804 BTRFS_MIXED_BACKREF_REV)
1805 ret = btrfs_drop_snapshot(root, NULL, 0, 0);
1807 ret =btrfs_drop_snapshot(root, NULL, 1, 0);