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 kmem_cache_free(btrfs_transaction_cachep
, transaction
);
47 static noinline
void switch_commit_root(struct btrfs_root
*root
)
49 free_extent_buffer(root
->commit_root
);
50 root
->commit_root
= btrfs_root_node(root
);
53 static inline int can_join_transaction(struct btrfs_transaction
*trans
,
56 return !(trans
->in_commit
&&
58 type
!= TRANS_JOIN_NOLOCK
);
62 * either allocate a new transaction or hop into the existing one
64 static noinline
int join_transaction(struct btrfs_root
*root
, int type
)
66 struct btrfs_transaction
*cur_trans
;
67 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
69 spin_lock(&fs_info
->trans_lock
);
71 /* The file system has been taken offline. No new transactions. */
72 if (test_bit(BTRFS_FS_STATE_ERROR
, &fs_info
->fs_state
)) {
73 spin_unlock(&fs_info
->trans_lock
);
77 if (fs_info
->trans_no_join
) {
79 * If we are JOIN_NOLOCK we're already committing a current
80 * transaction, we just need a handle to deal with something
81 * when committing the transaction, such as inode cache and
82 * space cache. It is a special case.
84 if (type
!= TRANS_JOIN_NOLOCK
) {
85 spin_unlock(&fs_info
->trans_lock
);
90 cur_trans
= fs_info
->running_transaction
;
92 if (cur_trans
->aborted
) {
93 spin_unlock(&fs_info
->trans_lock
);
94 return cur_trans
->aborted
;
96 if (!can_join_transaction(cur_trans
, type
)) {
97 spin_unlock(&fs_info
->trans_lock
);
100 atomic_inc(&cur_trans
->use_count
);
101 atomic_inc(&cur_trans
->num_writers
);
102 cur_trans
->num_joined
++;
103 spin_unlock(&fs_info
->trans_lock
);
106 spin_unlock(&fs_info
->trans_lock
);
109 * If we are ATTACH, we just want to catch the current transaction,
110 * and commit it. If there is no transaction, just return ENOENT.
112 if (type
== TRANS_ATTACH
)
115 cur_trans
= kmem_cache_alloc(btrfs_transaction_cachep
, GFP_NOFS
);
119 spin_lock(&fs_info
->trans_lock
);
120 if (fs_info
->running_transaction
) {
122 * someone started a transaction after we unlocked. Make sure
123 * to redo the trans_no_join checks above
125 kmem_cache_free(btrfs_transaction_cachep
, cur_trans
);
126 cur_trans
= fs_info
->running_transaction
;
128 } else if (test_bit(BTRFS_FS_STATE_ERROR
, &fs_info
->fs_state
)) {
129 spin_unlock(&fs_info
->trans_lock
);
130 kmem_cache_free(btrfs_transaction_cachep
, cur_trans
);
134 atomic_set(&cur_trans
->num_writers
, 1);
135 cur_trans
->num_joined
= 0;
136 init_waitqueue_head(&cur_trans
->writer_wait
);
137 init_waitqueue_head(&cur_trans
->commit_wait
);
138 cur_trans
->in_commit
= 0;
139 cur_trans
->blocked
= 0;
141 * One for this trans handle, one so it will live on until we
142 * commit the transaction.
144 atomic_set(&cur_trans
->use_count
, 2);
145 cur_trans
->commit_done
= 0;
146 cur_trans
->start_time
= get_seconds();
148 cur_trans
->delayed_refs
.root
= RB_ROOT
;
149 cur_trans
->delayed_refs
.num_entries
= 0;
150 cur_trans
->delayed_refs
.num_heads_ready
= 0;
151 cur_trans
->delayed_refs
.num_heads
= 0;
152 cur_trans
->delayed_refs
.flushing
= 0;
153 cur_trans
->delayed_refs
.run_delayed_start
= 0;
156 * although the tree mod log is per file system and not per transaction,
157 * the log must never go across transaction boundaries.
160 if (!list_empty(&fs_info
->tree_mod_seq_list
))
161 WARN(1, KERN_ERR
"btrfs: tree_mod_seq_list not empty when "
162 "creating a fresh transaction\n");
163 if (!RB_EMPTY_ROOT(&fs_info
->tree_mod_log
))
164 WARN(1, KERN_ERR
"btrfs: tree_mod_log rb tree not empty when "
165 "creating a fresh transaction\n");
166 atomic_set(&fs_info
->tree_mod_seq
, 0);
168 spin_lock_init(&cur_trans
->commit_lock
);
169 spin_lock_init(&cur_trans
->delayed_refs
.lock
);
171 INIT_LIST_HEAD(&cur_trans
->pending_snapshots
);
172 INIT_LIST_HEAD(&cur_trans
->ordered_operations
);
173 list_add_tail(&cur_trans
->list
, &fs_info
->trans_list
);
174 extent_io_tree_init(&cur_trans
->dirty_pages
,
175 fs_info
->btree_inode
->i_mapping
);
176 fs_info
->generation
++;
177 cur_trans
->transid
= fs_info
->generation
;
178 fs_info
->running_transaction
= cur_trans
;
179 cur_trans
->aborted
= 0;
180 spin_unlock(&fs_info
->trans_lock
);
186 * this does all the record keeping required to make sure that a reference
187 * counted root is properly recorded in a given transaction. This is required
188 * to make sure the old root from before we joined the transaction is deleted
189 * when the transaction commits
191 static int record_root_in_trans(struct btrfs_trans_handle
*trans
,
192 struct btrfs_root
*root
)
194 if (root
->ref_cows
&& root
->last_trans
< trans
->transid
) {
195 WARN_ON(root
== root
->fs_info
->extent_root
);
196 WARN_ON(root
->commit_root
!= root
->node
);
199 * see below for in_trans_setup usage rules
200 * we have the reloc mutex held now, so there
201 * is only one writer in this function
203 root
->in_trans_setup
= 1;
205 /* make sure readers find in_trans_setup before
206 * they find our root->last_trans update
210 spin_lock(&root
->fs_info
->fs_roots_radix_lock
);
211 if (root
->last_trans
== trans
->transid
) {
212 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
215 radix_tree_tag_set(&root
->fs_info
->fs_roots_radix
,
216 (unsigned long)root
->root_key
.objectid
,
217 BTRFS_ROOT_TRANS_TAG
);
218 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
219 root
->last_trans
= trans
->transid
;
221 /* this is pretty tricky. We don't want to
222 * take the relocation lock in btrfs_record_root_in_trans
223 * unless we're really doing the first setup for this root in
226 * Normally we'd use root->last_trans as a flag to decide
227 * if we want to take the expensive mutex.
229 * But, we have to set root->last_trans before we
230 * init the relocation root, otherwise, we trip over warnings
231 * in ctree.c. The solution used here is to flag ourselves
232 * with root->in_trans_setup. When this is 1, we're still
233 * fixing up the reloc trees and everyone must wait.
235 * When this is zero, they can trust root->last_trans and fly
236 * through btrfs_record_root_in_trans without having to take the
237 * lock. smp_wmb() makes sure that all the writes above are
238 * done before we pop in the zero below
240 btrfs_init_reloc_root(trans
, root
);
242 root
->in_trans_setup
= 0;
248 int btrfs_record_root_in_trans(struct btrfs_trans_handle
*trans
,
249 struct btrfs_root
*root
)
255 * see record_root_in_trans for comments about in_trans_setup usage
259 if (root
->last_trans
== trans
->transid
&&
260 !root
->in_trans_setup
)
263 mutex_lock(&root
->fs_info
->reloc_mutex
);
264 record_root_in_trans(trans
, root
);
265 mutex_unlock(&root
->fs_info
->reloc_mutex
);
270 /* wait for commit against the current transaction to become unblocked
271 * when this is done, it is safe to start a new transaction, but the current
272 * transaction might not be fully on disk.
274 static void wait_current_trans(struct btrfs_root
*root
)
276 struct btrfs_transaction
*cur_trans
;
278 spin_lock(&root
->fs_info
->trans_lock
);
279 cur_trans
= root
->fs_info
->running_transaction
;
280 if (cur_trans
&& cur_trans
->blocked
) {
281 atomic_inc(&cur_trans
->use_count
);
282 spin_unlock(&root
->fs_info
->trans_lock
);
284 wait_event(root
->fs_info
->transaction_wait
,
285 !cur_trans
->blocked
);
286 put_transaction(cur_trans
);
288 spin_unlock(&root
->fs_info
->trans_lock
);
292 static int may_wait_transaction(struct btrfs_root
*root
, int type
)
294 if (root
->fs_info
->log_root_recovering
)
297 if (type
== TRANS_USERSPACE
)
300 if (type
== TRANS_START
&&
301 !atomic_read(&root
->fs_info
->open_ioctl_trans
))
307 static struct btrfs_trans_handle
*
308 start_transaction(struct btrfs_root
*root
, u64 num_items
, int type
,
309 enum btrfs_reserve_flush_enum flush
)
311 struct btrfs_trans_handle
*h
;
312 struct btrfs_transaction
*cur_trans
;
315 u64 qgroup_reserved
= 0;
317 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
))
318 return ERR_PTR(-EROFS
);
320 if (current
->journal_info
) {
321 WARN_ON(type
!= TRANS_JOIN
&& type
!= TRANS_JOIN_NOLOCK
);
322 h
= current
->journal_info
;
324 WARN_ON(h
->use_count
> 2);
325 h
->orig_rsv
= h
->block_rsv
;
331 * Do the reservation before we join the transaction so we can do all
332 * the appropriate flushing if need be.
334 if (num_items
> 0 && root
!= root
->fs_info
->chunk_root
) {
335 if (root
->fs_info
->quota_enabled
&&
336 is_fstree(root
->root_key
.objectid
)) {
337 qgroup_reserved
= num_items
* root
->leafsize
;
338 ret
= btrfs_qgroup_reserve(root
, qgroup_reserved
);
343 num_bytes
= btrfs_calc_trans_metadata_size(root
, num_items
);
344 ret
= btrfs_block_rsv_add(root
,
345 &root
->fs_info
->trans_block_rsv
,
351 h
= kmem_cache_alloc(btrfs_trans_handle_cachep
, GFP_NOFS
);
358 * If we are JOIN_NOLOCK we're already committing a transaction and
359 * waiting on this guy, so we don't need to do the sb_start_intwrite
360 * because we're already holding a ref. We need this because we could
361 * have raced in and did an fsync() on a file which can kick a commit
362 * and then we deadlock with somebody doing a freeze.
364 * If we are ATTACH, it means we just want to catch the current
365 * transaction and commit it, so we needn't do sb_start_intwrite().
367 if (type
< TRANS_JOIN_NOLOCK
)
368 sb_start_intwrite(root
->fs_info
->sb
);
370 if (may_wait_transaction(root
, type
))
371 wait_current_trans(root
);
374 ret
= join_transaction(root
, type
);
376 wait_current_trans(root
);
377 if (unlikely(type
== TRANS_ATTACH
))
380 } while (ret
== -EBUSY
);
383 /* We must get the transaction if we are JOIN_NOLOCK. */
384 BUG_ON(type
== TRANS_JOIN_NOLOCK
);
388 cur_trans
= root
->fs_info
->running_transaction
;
390 h
->transid
= cur_trans
->transid
;
391 h
->transaction
= cur_trans
;
393 h
->bytes_reserved
= 0;
395 h
->delayed_ref_updates
= 0;
401 h
->qgroup_reserved
= 0;
402 h
->delayed_ref_elem
.seq
= 0;
404 h
->allocating_chunk
= false;
405 INIT_LIST_HEAD(&h
->qgroup_ref_list
);
406 INIT_LIST_HEAD(&h
->new_bgs
);
409 if (cur_trans
->blocked
&& may_wait_transaction(root
, type
)) {
410 btrfs_commit_transaction(h
, root
);
415 trace_btrfs_space_reservation(root
->fs_info
, "transaction",
416 h
->transid
, num_bytes
, 1);
417 h
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
418 h
->bytes_reserved
= num_bytes
;
420 h
->qgroup_reserved
= qgroup_reserved
;
423 btrfs_record_root_in_trans(h
, root
);
425 if (!current
->journal_info
&& type
!= TRANS_USERSPACE
)
426 current
->journal_info
= h
;
430 if (type
< TRANS_JOIN_NOLOCK
)
431 sb_end_intwrite(root
->fs_info
->sb
);
432 kmem_cache_free(btrfs_trans_handle_cachep
, h
);
435 btrfs_block_rsv_release(root
, &root
->fs_info
->trans_block_rsv
,
439 btrfs_qgroup_free(root
, qgroup_reserved
);
443 struct btrfs_trans_handle
*btrfs_start_transaction(struct btrfs_root
*root
,
446 return start_transaction(root
, num_items
, TRANS_START
,
447 BTRFS_RESERVE_FLUSH_ALL
);
450 struct btrfs_trans_handle
*btrfs_start_transaction_lflush(
451 struct btrfs_root
*root
, int num_items
)
453 return start_transaction(root
, num_items
, TRANS_START
,
454 BTRFS_RESERVE_FLUSH_LIMIT
);
457 struct btrfs_trans_handle
*btrfs_join_transaction(struct btrfs_root
*root
)
459 return start_transaction(root
, 0, TRANS_JOIN
, 0);
462 struct btrfs_trans_handle
*btrfs_join_transaction_nolock(struct btrfs_root
*root
)
464 return start_transaction(root
, 0, TRANS_JOIN_NOLOCK
, 0);
467 struct btrfs_trans_handle
*btrfs_start_ioctl_transaction(struct btrfs_root
*root
)
469 return start_transaction(root
, 0, TRANS_USERSPACE
, 0);
473 * btrfs_attach_transaction() - catch the running transaction
475 * It is used when we want to commit the current the transaction, but
476 * don't want to start a new one.
478 * Note: If this function return -ENOENT, it just means there is no
479 * running transaction. But it is possible that the inactive transaction
480 * is still in the memory, not fully on disk. If you hope there is no
481 * inactive transaction in the fs when -ENOENT is returned, you should
483 * btrfs_attach_transaction_barrier()
485 struct btrfs_trans_handle
*btrfs_attach_transaction(struct btrfs_root
*root
)
487 return start_transaction(root
, 0, TRANS_ATTACH
, 0);
491 * btrfs_attach_transaction() - catch the running transaction
493 * It is similar to the above function, the differentia is this one
494 * will wait for all the inactive transactions until they fully
497 struct btrfs_trans_handle
*
498 btrfs_attach_transaction_barrier(struct btrfs_root
*root
)
500 struct btrfs_trans_handle
*trans
;
502 trans
= start_transaction(root
, 0, TRANS_ATTACH
, 0);
503 if (IS_ERR(trans
) && PTR_ERR(trans
) == -ENOENT
)
504 btrfs_wait_for_commit(root
, 0);
509 /* wait for a transaction commit to be fully complete */
510 static noinline
void wait_for_commit(struct btrfs_root
*root
,
511 struct btrfs_transaction
*commit
)
513 wait_event(commit
->commit_wait
, commit
->commit_done
);
516 int btrfs_wait_for_commit(struct btrfs_root
*root
, u64 transid
)
518 struct btrfs_transaction
*cur_trans
= NULL
, *t
;
522 if (transid
<= root
->fs_info
->last_trans_committed
)
526 /* find specified transaction */
527 spin_lock(&root
->fs_info
->trans_lock
);
528 list_for_each_entry(t
, &root
->fs_info
->trans_list
, list
) {
529 if (t
->transid
== transid
) {
531 atomic_inc(&cur_trans
->use_count
);
535 if (t
->transid
> transid
) {
540 spin_unlock(&root
->fs_info
->trans_lock
);
541 /* The specified transaction doesn't exist */
545 /* find newest transaction that is committing | committed */
546 spin_lock(&root
->fs_info
->trans_lock
);
547 list_for_each_entry_reverse(t
, &root
->fs_info
->trans_list
,
553 atomic_inc(&cur_trans
->use_count
);
557 spin_unlock(&root
->fs_info
->trans_lock
);
559 goto out
; /* nothing committing|committed */
562 wait_for_commit(root
, cur_trans
);
563 put_transaction(cur_trans
);
568 void btrfs_throttle(struct btrfs_root
*root
)
570 if (!atomic_read(&root
->fs_info
->open_ioctl_trans
))
571 wait_current_trans(root
);
574 static int should_end_transaction(struct btrfs_trans_handle
*trans
,
575 struct btrfs_root
*root
)
579 ret
= btrfs_block_rsv_check(root
, &root
->fs_info
->global_block_rsv
, 5);
583 int btrfs_should_end_transaction(struct btrfs_trans_handle
*trans
,
584 struct btrfs_root
*root
)
586 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
591 if (cur_trans
->blocked
|| cur_trans
->delayed_refs
.flushing
)
594 updates
= trans
->delayed_ref_updates
;
595 trans
->delayed_ref_updates
= 0;
597 err
= btrfs_run_delayed_refs(trans
, root
, updates
);
598 if (err
) /* Error code will also eval true */
602 return should_end_transaction(trans
, root
);
605 static int __btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
606 struct btrfs_root
*root
, int throttle
)
608 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
609 struct btrfs_fs_info
*info
= root
->fs_info
;
611 int lock
= (trans
->type
!= TRANS_JOIN_NOLOCK
);
614 if (--trans
->use_count
) {
615 trans
->block_rsv
= trans
->orig_rsv
;
620 * do the qgroup accounting as early as possible
622 err
= btrfs_delayed_refs_qgroup_accounting(trans
, info
);
624 btrfs_trans_release_metadata(trans
, root
);
625 trans
->block_rsv
= NULL
;
627 * the same root has to be passed to start_transaction and
628 * end_transaction. Subvolume quota depends on this.
630 WARN_ON(trans
->root
!= root
);
632 if (trans
->qgroup_reserved
) {
633 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
634 trans
->qgroup_reserved
= 0;
637 if (!list_empty(&trans
->new_bgs
))
638 btrfs_create_pending_block_groups(trans
, root
);
641 unsigned long cur
= trans
->delayed_ref_updates
;
642 trans
->delayed_ref_updates
= 0;
644 trans
->transaction
->delayed_refs
.num_heads_ready
> 64) {
645 trans
->delayed_ref_updates
= 0;
646 btrfs_run_delayed_refs(trans
, root
, cur
);
652 btrfs_trans_release_metadata(trans
, root
);
653 trans
->block_rsv
= NULL
;
655 if (!list_empty(&trans
->new_bgs
))
656 btrfs_create_pending_block_groups(trans
, root
);
658 if (lock
&& !atomic_read(&root
->fs_info
->open_ioctl_trans
) &&
659 should_end_transaction(trans
, root
)) {
660 trans
->transaction
->blocked
= 1;
664 if (lock
&& cur_trans
->blocked
&& !cur_trans
->in_commit
) {
667 * We may race with somebody else here so end up having
668 * to call end_transaction on ourselves again, so inc
672 return btrfs_commit_transaction(trans
, root
);
674 wake_up_process(info
->transaction_kthread
);
678 if (trans
->type
< TRANS_JOIN_NOLOCK
)
679 sb_end_intwrite(root
->fs_info
->sb
);
681 WARN_ON(cur_trans
!= info
->running_transaction
);
682 WARN_ON(atomic_read(&cur_trans
->num_writers
) < 1);
683 atomic_dec(&cur_trans
->num_writers
);
686 if (waitqueue_active(&cur_trans
->writer_wait
))
687 wake_up(&cur_trans
->writer_wait
);
688 put_transaction(cur_trans
);
690 if (current
->journal_info
== trans
)
691 current
->journal_info
= NULL
;
694 btrfs_run_delayed_iputs(root
);
696 if (trans
->aborted
||
697 test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
))
699 assert_qgroups_uptodate(trans
);
701 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
705 int btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
706 struct btrfs_root
*root
)
710 ret
= __btrfs_end_transaction(trans
, root
, 0);
716 int btrfs_end_transaction_throttle(struct btrfs_trans_handle
*trans
,
717 struct btrfs_root
*root
)
721 ret
= __btrfs_end_transaction(trans
, root
, 1);
727 int btrfs_end_transaction_dmeta(struct btrfs_trans_handle
*trans
,
728 struct btrfs_root
*root
)
730 return __btrfs_end_transaction(trans
, root
, 1);
734 * when btree blocks are allocated, they have some corresponding bits set for
735 * them in one of two extent_io trees. This is used to make sure all of
736 * those extents are sent to disk but does not wait on them
738 int btrfs_write_marked_extents(struct btrfs_root
*root
,
739 struct extent_io_tree
*dirty_pages
, int mark
)
743 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
744 struct extent_state
*cached_state
= NULL
;
748 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
749 mark
, &cached_state
)) {
750 convert_extent_bit(dirty_pages
, start
, end
, EXTENT_NEED_WAIT
,
751 mark
, &cached_state
, GFP_NOFS
);
753 err
= filemap_fdatawrite_range(mapping
, start
, end
);
765 * when btree blocks are allocated, they have some corresponding bits set for
766 * them in one of two extent_io trees. This is used to make sure all of
767 * those extents are on disk for transaction or log commit. We wait
768 * on all the pages and clear them from the dirty pages state tree
770 int btrfs_wait_marked_extents(struct btrfs_root
*root
,
771 struct extent_io_tree
*dirty_pages
, int mark
)
775 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
776 struct extent_state
*cached_state
= NULL
;
780 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
781 EXTENT_NEED_WAIT
, &cached_state
)) {
782 clear_extent_bit(dirty_pages
, start
, end
, EXTENT_NEED_WAIT
,
783 0, 0, &cached_state
, GFP_NOFS
);
784 err
= filemap_fdatawait_range(mapping
, start
, end
);
796 * when btree blocks are allocated, they have some corresponding bits set for
797 * them in one of two extent_io trees. This is used to make sure all of
798 * those extents are on disk for transaction or log commit
800 int btrfs_write_and_wait_marked_extents(struct btrfs_root
*root
,
801 struct extent_io_tree
*dirty_pages
, int mark
)
806 ret
= btrfs_write_marked_extents(root
, dirty_pages
, mark
);
807 ret2
= btrfs_wait_marked_extents(root
, dirty_pages
, mark
);
816 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle
*trans
,
817 struct btrfs_root
*root
)
819 if (!trans
|| !trans
->transaction
) {
820 struct inode
*btree_inode
;
821 btree_inode
= root
->fs_info
->btree_inode
;
822 return filemap_write_and_wait(btree_inode
->i_mapping
);
824 return btrfs_write_and_wait_marked_extents(root
,
825 &trans
->transaction
->dirty_pages
,
830 * this is used to update the root pointer in the tree of tree roots.
832 * But, in the case of the extent allocation tree, updating the root
833 * pointer may allocate blocks which may change the root of the extent
836 * So, this loops and repeats and makes sure the cowonly root didn't
837 * change while the root pointer was being updated in the metadata.
839 static int update_cowonly_root(struct btrfs_trans_handle
*trans
,
840 struct btrfs_root
*root
)
845 struct btrfs_root
*tree_root
= root
->fs_info
->tree_root
;
847 old_root_used
= btrfs_root_used(&root
->root_item
);
848 btrfs_write_dirty_block_groups(trans
, root
);
851 old_root_bytenr
= btrfs_root_bytenr(&root
->root_item
);
852 if (old_root_bytenr
== root
->node
->start
&&
853 old_root_used
== btrfs_root_used(&root
->root_item
))
856 btrfs_set_root_node(&root
->root_item
, root
->node
);
857 ret
= btrfs_update_root(trans
, tree_root
,
863 old_root_used
= btrfs_root_used(&root
->root_item
);
864 ret
= btrfs_write_dirty_block_groups(trans
, root
);
869 if (root
!= root
->fs_info
->extent_root
)
870 switch_commit_root(root
);
876 * update all the cowonly tree roots on disk
878 * The error handling in this function may not be obvious. Any of the
879 * failures will cause the file system to go offline. We still need
880 * to clean up the delayed refs.
882 static noinline
int commit_cowonly_roots(struct btrfs_trans_handle
*trans
,
883 struct btrfs_root
*root
)
885 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
886 struct list_head
*next
;
887 struct extent_buffer
*eb
;
890 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
894 eb
= btrfs_lock_root_node(fs_info
->tree_root
);
895 ret
= btrfs_cow_block(trans
, fs_info
->tree_root
, eb
, NULL
,
897 btrfs_tree_unlock(eb
);
898 free_extent_buffer(eb
);
903 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
907 ret
= btrfs_run_dev_stats(trans
, root
->fs_info
);
909 ret
= btrfs_run_dev_replace(trans
, root
->fs_info
);
912 ret
= btrfs_run_qgroups(trans
, root
->fs_info
);
915 /* run_qgroups might have added some more refs */
916 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
919 while (!list_empty(&fs_info
->dirty_cowonly_roots
)) {
920 next
= fs_info
->dirty_cowonly_roots
.next
;
922 root
= list_entry(next
, struct btrfs_root
, dirty_list
);
924 ret
= update_cowonly_root(trans
, root
);
929 down_write(&fs_info
->extent_commit_sem
);
930 switch_commit_root(fs_info
->extent_root
);
931 up_write(&fs_info
->extent_commit_sem
);
933 btrfs_after_dev_replace_commit(fs_info
);
939 * dead roots are old snapshots that need to be deleted. This allocates
940 * a dirty root struct and adds it into the list of dead roots that need to
943 int btrfs_add_dead_root(struct btrfs_root
*root
)
945 spin_lock(&root
->fs_info
->trans_lock
);
946 list_add(&root
->root_list
, &root
->fs_info
->dead_roots
);
947 spin_unlock(&root
->fs_info
->trans_lock
);
952 * update all the cowonly tree roots on disk
954 static noinline
int commit_fs_roots(struct btrfs_trans_handle
*trans
,
955 struct btrfs_root
*root
)
957 struct btrfs_root
*gang
[8];
958 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
963 spin_lock(&fs_info
->fs_roots_radix_lock
);
965 ret
= radix_tree_gang_lookup_tag(&fs_info
->fs_roots_radix
,
968 BTRFS_ROOT_TRANS_TAG
);
971 for (i
= 0; i
< ret
; i
++) {
973 radix_tree_tag_clear(&fs_info
->fs_roots_radix
,
974 (unsigned long)root
->root_key
.objectid
,
975 BTRFS_ROOT_TRANS_TAG
);
976 spin_unlock(&fs_info
->fs_roots_radix_lock
);
978 btrfs_free_log(trans
, root
);
979 btrfs_update_reloc_root(trans
, root
);
980 btrfs_orphan_commit_root(trans
, root
);
982 btrfs_save_ino_cache(root
, trans
);
984 /* see comments in should_cow_block() */
988 if (root
->commit_root
!= root
->node
) {
989 mutex_lock(&root
->fs_commit_mutex
);
990 switch_commit_root(root
);
991 btrfs_unpin_free_ino(root
);
992 mutex_unlock(&root
->fs_commit_mutex
);
994 btrfs_set_root_node(&root
->root_item
,
998 err
= btrfs_update_root(trans
, fs_info
->tree_root
,
1001 spin_lock(&fs_info
->fs_roots_radix_lock
);
1006 spin_unlock(&fs_info
->fs_roots_radix_lock
);
1011 * defrag a given btree.
1012 * Every leaf in the btree is read and defragged.
1014 int btrfs_defrag_root(struct btrfs_root
*root
)
1016 struct btrfs_fs_info
*info
= root
->fs_info
;
1017 struct btrfs_trans_handle
*trans
;
1020 if (xchg(&root
->defrag_running
, 1))
1024 trans
= btrfs_start_transaction(root
, 0);
1026 return PTR_ERR(trans
);
1028 ret
= btrfs_defrag_leaves(trans
, root
);
1030 btrfs_end_transaction(trans
, root
);
1031 btrfs_btree_balance_dirty(info
->tree_root
);
1034 if (btrfs_fs_closing(root
->fs_info
) || ret
!= -EAGAIN
)
1037 if (btrfs_defrag_cancelled(root
->fs_info
)) {
1038 printk(KERN_DEBUG
"btrfs: defrag_root cancelled\n");
1043 root
->defrag_running
= 0;
1048 * new snapshots need to be created at a very specific time in the
1049 * transaction commit. This does the actual creation
1051 static noinline
int create_pending_snapshot(struct btrfs_trans_handle
*trans
,
1052 struct btrfs_fs_info
*fs_info
,
1053 struct btrfs_pending_snapshot
*pending
)
1055 struct btrfs_key key
;
1056 struct btrfs_root_item
*new_root_item
;
1057 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
1058 struct btrfs_root
*root
= pending
->root
;
1059 struct btrfs_root
*parent_root
;
1060 struct btrfs_block_rsv
*rsv
;
1061 struct inode
*parent_inode
;
1062 struct btrfs_path
*path
;
1063 struct btrfs_dir_item
*dir_item
;
1064 struct dentry
*parent
;
1065 struct dentry
*dentry
;
1066 struct extent_buffer
*tmp
;
1067 struct extent_buffer
*old
;
1068 struct timespec cur_time
= CURRENT_TIME
;
1076 path
= btrfs_alloc_path();
1078 ret
= pending
->error
= -ENOMEM
;
1079 goto path_alloc_fail
;
1082 new_root_item
= kmalloc(sizeof(*new_root_item
), GFP_NOFS
);
1083 if (!new_root_item
) {
1084 ret
= pending
->error
= -ENOMEM
;
1085 goto root_item_alloc_fail
;
1088 ret
= btrfs_find_free_objectid(tree_root
, &objectid
);
1090 pending
->error
= ret
;
1091 goto no_free_objectid
;
1094 btrfs_reloc_pre_snapshot(trans
, pending
, &to_reserve
);
1096 if (to_reserve
> 0) {
1097 ret
= btrfs_block_rsv_add(root
, &pending
->block_rsv
,
1099 BTRFS_RESERVE_NO_FLUSH
);
1101 pending
->error
= ret
;
1102 goto no_free_objectid
;
1106 ret
= btrfs_qgroup_inherit(trans
, fs_info
, root
->root_key
.objectid
,
1107 objectid
, pending
->inherit
);
1109 pending
->error
= ret
;
1110 goto no_free_objectid
;
1113 key
.objectid
= objectid
;
1114 key
.offset
= (u64
)-1;
1115 key
.type
= BTRFS_ROOT_ITEM_KEY
;
1117 rsv
= trans
->block_rsv
;
1118 trans
->block_rsv
= &pending
->block_rsv
;
1120 dentry
= pending
->dentry
;
1121 parent
= dget_parent(dentry
);
1122 parent_inode
= parent
->d_inode
;
1123 parent_root
= BTRFS_I(parent_inode
)->root
;
1124 record_root_in_trans(trans
, parent_root
);
1127 * insert the directory item
1129 ret
= btrfs_set_inode_index(parent_inode
, &index
);
1130 BUG_ON(ret
); /* -ENOMEM */
1132 /* check if there is a file/dir which has the same name. */
1133 dir_item
= btrfs_lookup_dir_item(NULL
, parent_root
, path
,
1134 btrfs_ino(parent_inode
),
1135 dentry
->d_name
.name
,
1136 dentry
->d_name
.len
, 0);
1137 if (dir_item
!= NULL
&& !IS_ERR(dir_item
)) {
1138 pending
->error
= -EEXIST
;
1140 } else if (IS_ERR(dir_item
)) {
1141 ret
= PTR_ERR(dir_item
);
1142 btrfs_abort_transaction(trans
, root
, ret
);
1145 btrfs_release_path(path
);
1148 * pull in the delayed directory update
1149 * and the delayed inode item
1150 * otherwise we corrupt the FS during
1153 ret
= btrfs_run_delayed_items(trans
, root
);
1154 if (ret
) { /* Transaction aborted */
1155 btrfs_abort_transaction(trans
, root
, ret
);
1159 record_root_in_trans(trans
, root
);
1160 btrfs_set_root_last_snapshot(&root
->root_item
, trans
->transid
);
1161 memcpy(new_root_item
, &root
->root_item
, sizeof(*new_root_item
));
1162 btrfs_check_and_init_root_item(new_root_item
);
1164 root_flags
= btrfs_root_flags(new_root_item
);
1165 if (pending
->readonly
)
1166 root_flags
|= BTRFS_ROOT_SUBVOL_RDONLY
;
1168 root_flags
&= ~BTRFS_ROOT_SUBVOL_RDONLY
;
1169 btrfs_set_root_flags(new_root_item
, root_flags
);
1171 btrfs_set_root_generation_v2(new_root_item
,
1173 uuid_le_gen(&new_uuid
);
1174 memcpy(new_root_item
->uuid
, new_uuid
.b
, BTRFS_UUID_SIZE
);
1175 memcpy(new_root_item
->parent_uuid
, root
->root_item
.uuid
,
1177 new_root_item
->otime
.sec
= cpu_to_le64(cur_time
.tv_sec
);
1178 new_root_item
->otime
.nsec
= cpu_to_le32(cur_time
.tv_nsec
);
1179 btrfs_set_root_otransid(new_root_item
, trans
->transid
);
1180 memset(&new_root_item
->stime
, 0, sizeof(new_root_item
->stime
));
1181 memset(&new_root_item
->rtime
, 0, sizeof(new_root_item
->rtime
));
1182 btrfs_set_root_stransid(new_root_item
, 0);
1183 btrfs_set_root_rtransid(new_root_item
, 0);
1185 old
= btrfs_lock_root_node(root
);
1186 ret
= btrfs_cow_block(trans
, root
, old
, NULL
, 0, &old
);
1188 btrfs_tree_unlock(old
);
1189 free_extent_buffer(old
);
1190 btrfs_abort_transaction(trans
, root
, ret
);
1194 btrfs_set_lock_blocking(old
);
1196 ret
= btrfs_copy_root(trans
, root
, old
, &tmp
, objectid
);
1197 /* clean up in any case */
1198 btrfs_tree_unlock(old
);
1199 free_extent_buffer(old
);
1201 btrfs_abort_transaction(trans
, root
, ret
);
1205 /* see comments in should_cow_block() */
1206 root
->force_cow
= 1;
1209 btrfs_set_root_node(new_root_item
, tmp
);
1210 /* record when the snapshot was created in key.offset */
1211 key
.offset
= trans
->transid
;
1212 ret
= btrfs_insert_root(trans
, tree_root
, &key
, new_root_item
);
1213 btrfs_tree_unlock(tmp
);
1214 free_extent_buffer(tmp
);
1216 btrfs_abort_transaction(trans
, root
, ret
);
1221 * insert root back/forward references
1223 ret
= btrfs_add_root_ref(trans
, tree_root
, objectid
,
1224 parent_root
->root_key
.objectid
,
1225 btrfs_ino(parent_inode
), index
,
1226 dentry
->d_name
.name
, dentry
->d_name
.len
);
1228 btrfs_abort_transaction(trans
, root
, ret
);
1232 key
.offset
= (u64
)-1;
1233 pending
->snap
= btrfs_read_fs_root_no_name(root
->fs_info
, &key
);
1234 if (IS_ERR(pending
->snap
)) {
1235 ret
= PTR_ERR(pending
->snap
);
1236 btrfs_abort_transaction(trans
, root
, ret
);
1240 ret
= btrfs_reloc_post_snapshot(trans
, pending
);
1242 btrfs_abort_transaction(trans
, root
, ret
);
1246 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1248 btrfs_abort_transaction(trans
, root
, ret
);
1252 ret
= btrfs_insert_dir_item(trans
, parent_root
,
1253 dentry
->d_name
.name
, dentry
->d_name
.len
,
1255 BTRFS_FT_DIR
, index
);
1256 /* We have check then name at the beginning, so it is impossible. */
1257 BUG_ON(ret
== -EEXIST
|| ret
== -EOVERFLOW
);
1259 btrfs_abort_transaction(trans
, root
, ret
);
1263 btrfs_i_size_write(parent_inode
, parent_inode
->i_size
+
1264 dentry
->d_name
.len
* 2);
1265 parent_inode
->i_mtime
= parent_inode
->i_ctime
= CURRENT_TIME
;
1266 ret
= btrfs_update_inode_fallback(trans
, parent_root
, parent_inode
);
1268 btrfs_abort_transaction(trans
, root
, ret
);
1271 trans
->block_rsv
= rsv
;
1273 kfree(new_root_item
);
1274 root_item_alloc_fail
:
1275 btrfs_free_path(path
);
1277 btrfs_block_rsv_release(root
, &pending
->block_rsv
, (u64
)-1);
1282 * create all the snapshots we've scheduled for creation
1284 static noinline
int create_pending_snapshots(struct btrfs_trans_handle
*trans
,
1285 struct btrfs_fs_info
*fs_info
)
1287 struct btrfs_pending_snapshot
*pending
;
1288 struct list_head
*head
= &trans
->transaction
->pending_snapshots
;
1290 list_for_each_entry(pending
, head
, list
)
1291 create_pending_snapshot(trans
, fs_info
, pending
);
1295 static void update_super_roots(struct btrfs_root
*root
)
1297 struct btrfs_root_item
*root_item
;
1298 struct btrfs_super_block
*super
;
1300 super
= root
->fs_info
->super_copy
;
1302 root_item
= &root
->fs_info
->chunk_root
->root_item
;
1303 super
->chunk_root
= root_item
->bytenr
;
1304 super
->chunk_root_generation
= root_item
->generation
;
1305 super
->chunk_root_level
= root_item
->level
;
1307 root_item
= &root
->fs_info
->tree_root
->root_item
;
1308 super
->root
= root_item
->bytenr
;
1309 super
->generation
= root_item
->generation
;
1310 super
->root_level
= root_item
->level
;
1311 if (btrfs_test_opt(root
, SPACE_CACHE
))
1312 super
->cache_generation
= root_item
->generation
;
1315 int btrfs_transaction_in_commit(struct btrfs_fs_info
*info
)
1318 spin_lock(&info
->trans_lock
);
1319 if (info
->running_transaction
)
1320 ret
= info
->running_transaction
->in_commit
;
1321 spin_unlock(&info
->trans_lock
);
1325 int btrfs_transaction_blocked(struct btrfs_fs_info
*info
)
1328 spin_lock(&info
->trans_lock
);
1329 if (info
->running_transaction
)
1330 ret
= info
->running_transaction
->blocked
;
1331 spin_unlock(&info
->trans_lock
);
1336 * wait for the current transaction commit to start and block subsequent
1339 static void wait_current_trans_commit_start(struct btrfs_root
*root
,
1340 struct btrfs_transaction
*trans
)
1342 wait_event(root
->fs_info
->transaction_blocked_wait
, trans
->in_commit
);
1346 * wait for the current transaction to start and then become unblocked.
1349 static void wait_current_trans_commit_start_and_unblock(struct btrfs_root
*root
,
1350 struct btrfs_transaction
*trans
)
1352 wait_event(root
->fs_info
->transaction_wait
,
1353 trans
->commit_done
|| (trans
->in_commit
&& !trans
->blocked
));
1357 * commit transactions asynchronously. once btrfs_commit_transaction_async
1358 * returns, any subsequent transaction will not be allowed to join.
1360 struct btrfs_async_commit
{
1361 struct btrfs_trans_handle
*newtrans
;
1362 struct btrfs_root
*root
;
1363 struct work_struct work
;
1366 static void do_async_commit(struct work_struct
*work
)
1368 struct btrfs_async_commit
*ac
=
1369 container_of(work
, struct btrfs_async_commit
, work
);
1372 * We've got freeze protection passed with the transaction.
1373 * Tell lockdep about it.
1375 if (ac
->newtrans
->type
< TRANS_JOIN_NOLOCK
)
1377 &ac
->root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1380 current
->journal_info
= ac
->newtrans
;
1382 btrfs_commit_transaction(ac
->newtrans
, ac
->root
);
1386 int btrfs_commit_transaction_async(struct btrfs_trans_handle
*trans
,
1387 struct btrfs_root
*root
,
1388 int wait_for_unblock
)
1390 struct btrfs_async_commit
*ac
;
1391 struct btrfs_transaction
*cur_trans
;
1393 ac
= kmalloc(sizeof(*ac
), GFP_NOFS
);
1397 INIT_WORK(&ac
->work
, do_async_commit
);
1399 ac
->newtrans
= btrfs_join_transaction(root
);
1400 if (IS_ERR(ac
->newtrans
)) {
1401 int err
= PTR_ERR(ac
->newtrans
);
1406 /* take transaction reference */
1407 cur_trans
= trans
->transaction
;
1408 atomic_inc(&cur_trans
->use_count
);
1410 btrfs_end_transaction(trans
, root
);
1413 * Tell lockdep we've released the freeze rwsem, since the
1414 * async commit thread will be the one to unlock it.
1416 if (trans
->type
< TRANS_JOIN_NOLOCK
)
1418 &root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1421 schedule_work(&ac
->work
);
1423 /* wait for transaction to start and unblock */
1424 if (wait_for_unblock
)
1425 wait_current_trans_commit_start_and_unblock(root
, cur_trans
);
1427 wait_current_trans_commit_start(root
, cur_trans
);
1429 if (current
->journal_info
== trans
)
1430 current
->journal_info
= NULL
;
1432 put_transaction(cur_trans
);
1437 static void cleanup_transaction(struct btrfs_trans_handle
*trans
,
1438 struct btrfs_root
*root
, int err
)
1440 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1442 WARN_ON(trans
->use_count
> 1);
1444 btrfs_abort_transaction(trans
, root
, err
);
1446 spin_lock(&root
->fs_info
->trans_lock
);
1447 list_del_init(&cur_trans
->list
);
1448 if (cur_trans
== root
->fs_info
->running_transaction
) {
1449 root
->fs_info
->running_transaction
= NULL
;
1450 root
->fs_info
->trans_no_join
= 0;
1452 spin_unlock(&root
->fs_info
->trans_lock
);
1454 btrfs_cleanup_one_transaction(trans
->transaction
, root
);
1456 put_transaction(cur_trans
);
1457 put_transaction(cur_trans
);
1459 trace_btrfs_transaction_commit(root
);
1461 btrfs_scrub_continue(root
);
1463 if (current
->journal_info
== trans
)
1464 current
->journal_info
= NULL
;
1466 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
1469 static int btrfs_flush_all_pending_stuffs(struct btrfs_trans_handle
*trans
,
1470 struct btrfs_root
*root
)
1472 int flush_on_commit
= btrfs_test_opt(root
, FLUSHONCOMMIT
);
1473 int snap_pending
= 0;
1476 if (!flush_on_commit
) {
1477 spin_lock(&root
->fs_info
->trans_lock
);
1478 if (!list_empty(&trans
->transaction
->pending_snapshots
))
1480 spin_unlock(&root
->fs_info
->trans_lock
);
1483 if (flush_on_commit
|| snap_pending
) {
1484 ret
= btrfs_start_delalloc_inodes(root
, 1);
1487 btrfs_wait_ordered_extents(root
, 1);
1490 ret
= btrfs_run_delayed_items(trans
, root
);
1495 * running the delayed items may have added new refs. account
1496 * them now so that they hinder processing of more delayed refs
1497 * as little as possible.
1499 btrfs_delayed_refs_qgroup_accounting(trans
, root
->fs_info
);
1502 * rename don't use btrfs_join_transaction, so, once we
1503 * set the transaction to blocked above, we aren't going
1504 * to get any new ordered operations. We can safely run
1505 * it here and no for sure that nothing new will be added
1508 ret
= btrfs_run_ordered_operations(trans
, root
, 1);
1514 * btrfs_transaction state sequence:
1515 * in_commit = 0, blocked = 0 (initial)
1516 * in_commit = 1, blocked = 1
1520 int btrfs_commit_transaction(struct btrfs_trans_handle
*trans
,
1521 struct btrfs_root
*root
)
1523 unsigned long joined
= 0;
1524 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1525 struct btrfs_transaction
*prev_trans
= NULL
;
1528 int should_grow
= 0;
1529 unsigned long now
= get_seconds();
1531 ret
= btrfs_run_ordered_operations(trans
, root
, 0);
1533 btrfs_abort_transaction(trans
, root
, ret
);
1534 btrfs_end_transaction(trans
, root
);
1538 /* Stop the commit early if ->aborted is set */
1539 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1540 ret
= cur_trans
->aborted
;
1541 btrfs_end_transaction(trans
, root
);
1545 /* make a pass through all the delayed refs we have so far
1546 * any runnings procs may add more while we are here
1548 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1550 btrfs_end_transaction(trans
, root
);
1554 btrfs_trans_release_metadata(trans
, root
);
1555 trans
->block_rsv
= NULL
;
1556 if (trans
->qgroup_reserved
) {
1557 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
1558 trans
->qgroup_reserved
= 0;
1561 cur_trans
= trans
->transaction
;
1564 * set the flushing flag so procs in this transaction have to
1565 * start sending their work down.
1567 cur_trans
->delayed_refs
.flushing
= 1;
1569 if (!list_empty(&trans
->new_bgs
))
1570 btrfs_create_pending_block_groups(trans
, root
);
1572 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1574 btrfs_end_transaction(trans
, root
);
1578 spin_lock(&cur_trans
->commit_lock
);
1579 if (cur_trans
->in_commit
) {
1580 spin_unlock(&cur_trans
->commit_lock
);
1581 atomic_inc(&cur_trans
->use_count
);
1582 ret
= btrfs_end_transaction(trans
, root
);
1584 wait_for_commit(root
, cur_trans
);
1586 put_transaction(cur_trans
);
1591 trans
->transaction
->in_commit
= 1;
1592 trans
->transaction
->blocked
= 1;
1593 spin_unlock(&cur_trans
->commit_lock
);
1594 wake_up(&root
->fs_info
->transaction_blocked_wait
);
1596 spin_lock(&root
->fs_info
->trans_lock
);
1597 if (cur_trans
->list
.prev
!= &root
->fs_info
->trans_list
) {
1598 prev_trans
= list_entry(cur_trans
->list
.prev
,
1599 struct btrfs_transaction
, list
);
1600 if (!prev_trans
->commit_done
) {
1601 atomic_inc(&prev_trans
->use_count
);
1602 spin_unlock(&root
->fs_info
->trans_lock
);
1604 wait_for_commit(root
, prev_trans
);
1606 put_transaction(prev_trans
);
1608 spin_unlock(&root
->fs_info
->trans_lock
);
1611 spin_unlock(&root
->fs_info
->trans_lock
);
1614 if (!btrfs_test_opt(root
, SSD
) &&
1615 (now
< cur_trans
->start_time
|| now
- cur_trans
->start_time
< 1))
1619 joined
= cur_trans
->num_joined
;
1621 WARN_ON(cur_trans
!= trans
->transaction
);
1623 ret
= btrfs_flush_all_pending_stuffs(trans
, root
);
1625 goto cleanup_transaction
;
1627 prepare_to_wait(&cur_trans
->writer_wait
, &wait
,
1628 TASK_UNINTERRUPTIBLE
);
1630 if (atomic_read(&cur_trans
->num_writers
) > 1)
1631 schedule_timeout(MAX_SCHEDULE_TIMEOUT
);
1632 else if (should_grow
)
1633 schedule_timeout(1);
1635 finish_wait(&cur_trans
->writer_wait
, &wait
);
1636 } while (atomic_read(&cur_trans
->num_writers
) > 1 ||
1637 (should_grow
&& cur_trans
->num_joined
!= joined
));
1639 ret
= btrfs_flush_all_pending_stuffs(trans
, root
);
1641 goto cleanup_transaction
;
1644 * Ok now we need to make sure to block out any other joins while we
1645 * commit the transaction. We could have started a join before setting
1646 * no_join so make sure to wait for num_writers to == 1 again.
1648 spin_lock(&root
->fs_info
->trans_lock
);
1649 root
->fs_info
->trans_no_join
= 1;
1650 spin_unlock(&root
->fs_info
->trans_lock
);
1651 wait_event(cur_trans
->writer_wait
,
1652 atomic_read(&cur_trans
->num_writers
) == 1);
1654 /* ->aborted might be set after the previous check, so check it */
1655 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1656 ret
= cur_trans
->aborted
;
1657 goto cleanup_transaction
;
1660 * the reloc mutex makes sure that we stop
1661 * the balancing code from coming in and moving
1662 * extents around in the middle of the commit
1664 mutex_lock(&root
->fs_info
->reloc_mutex
);
1667 * We needn't worry about the delayed items because we will
1668 * deal with them in create_pending_snapshot(), which is the
1669 * core function of the snapshot creation.
1671 ret
= create_pending_snapshots(trans
, root
->fs_info
);
1673 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1674 goto cleanup_transaction
;
1678 * We insert the dir indexes of the snapshots and update the inode
1679 * of the snapshots' parents after the snapshot creation, so there
1680 * are some delayed items which are not dealt with. Now deal with
1683 * We needn't worry that this operation will corrupt the snapshots,
1684 * because all the tree which are snapshoted will be forced to COW
1685 * the nodes and leaves.
1687 ret
= btrfs_run_delayed_items(trans
, root
);
1689 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1690 goto cleanup_transaction
;
1693 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1695 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1696 goto cleanup_transaction
;
1700 * make sure none of the code above managed to slip in a
1703 btrfs_assert_delayed_root_empty(root
);
1705 WARN_ON(cur_trans
!= trans
->transaction
);
1707 btrfs_scrub_pause(root
);
1708 /* btrfs_commit_tree_roots is responsible for getting the
1709 * various roots consistent with each other. Every pointer
1710 * in the tree of tree roots has to point to the most up to date
1711 * root for every subvolume and other tree. So, we have to keep
1712 * the tree logging code from jumping in and changing any
1715 * At this point in the commit, there can't be any tree-log
1716 * writers, but a little lower down we drop the trans mutex
1717 * and let new people in. By holding the tree_log_mutex
1718 * from now until after the super is written, we avoid races
1719 * with the tree-log code.
1721 mutex_lock(&root
->fs_info
->tree_log_mutex
);
1723 ret
= commit_fs_roots(trans
, root
);
1725 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1726 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1727 goto cleanup_transaction
;
1730 /* commit_fs_roots gets rid of all the tree log roots, it is now
1731 * safe to free the root of tree log roots
1733 btrfs_free_log_root_tree(trans
, root
->fs_info
);
1735 ret
= commit_cowonly_roots(trans
, root
);
1737 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1738 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1739 goto cleanup_transaction
;
1743 * The tasks which save the space cache and inode cache may also
1744 * update ->aborted, check it.
1746 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1747 ret
= cur_trans
->aborted
;
1748 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1749 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1750 goto cleanup_transaction
;
1753 btrfs_prepare_extent_commit(trans
, root
);
1755 cur_trans
= root
->fs_info
->running_transaction
;
1757 btrfs_set_root_node(&root
->fs_info
->tree_root
->root_item
,
1758 root
->fs_info
->tree_root
->node
);
1759 switch_commit_root(root
->fs_info
->tree_root
);
1761 btrfs_set_root_node(&root
->fs_info
->chunk_root
->root_item
,
1762 root
->fs_info
->chunk_root
->node
);
1763 switch_commit_root(root
->fs_info
->chunk_root
);
1765 assert_qgroups_uptodate(trans
);
1766 update_super_roots(root
);
1768 if (!root
->fs_info
->log_root_recovering
) {
1769 btrfs_set_super_log_root(root
->fs_info
->super_copy
, 0);
1770 btrfs_set_super_log_root_level(root
->fs_info
->super_copy
, 0);
1773 memcpy(root
->fs_info
->super_for_commit
, root
->fs_info
->super_copy
,
1774 sizeof(*root
->fs_info
->super_copy
));
1776 trans
->transaction
->blocked
= 0;
1777 spin_lock(&root
->fs_info
->trans_lock
);
1778 root
->fs_info
->running_transaction
= NULL
;
1779 root
->fs_info
->trans_no_join
= 0;
1780 spin_unlock(&root
->fs_info
->trans_lock
);
1781 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1783 wake_up(&root
->fs_info
->transaction_wait
);
1785 ret
= btrfs_write_and_wait_transaction(trans
, root
);
1787 btrfs_error(root
->fs_info
, ret
,
1788 "Error while writing out transaction.");
1789 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1790 goto cleanup_transaction
;
1793 ret
= write_ctree_super(trans
, root
, 0);
1795 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1796 goto cleanup_transaction
;
1800 * the super is written, we can safely allow the tree-loggers
1801 * to go about their business
1803 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1805 btrfs_finish_extent_commit(trans
, root
);
1807 cur_trans
->commit_done
= 1;
1809 root
->fs_info
->last_trans_committed
= cur_trans
->transid
;
1811 wake_up(&cur_trans
->commit_wait
);
1813 spin_lock(&root
->fs_info
->trans_lock
);
1814 list_del_init(&cur_trans
->list
);
1815 spin_unlock(&root
->fs_info
->trans_lock
);
1817 put_transaction(cur_trans
);
1818 put_transaction(cur_trans
);
1820 if (trans
->type
< TRANS_JOIN_NOLOCK
)
1821 sb_end_intwrite(root
->fs_info
->sb
);
1823 trace_btrfs_transaction_commit(root
);
1825 btrfs_scrub_continue(root
);
1827 if (current
->journal_info
== trans
)
1828 current
->journal_info
= NULL
;
1830 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
1832 if (current
!= root
->fs_info
->transaction_kthread
)
1833 btrfs_run_delayed_iputs(root
);
1837 cleanup_transaction
:
1838 btrfs_trans_release_metadata(trans
, root
);
1839 trans
->block_rsv
= NULL
;
1840 if (trans
->qgroup_reserved
) {
1841 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
1842 trans
->qgroup_reserved
= 0;
1844 btrfs_printk(root
->fs_info
, "Skipping commit of aborted transaction.\n");
1846 if (current
->journal_info
== trans
)
1847 current
->journal_info
= NULL
;
1848 cleanup_transaction(trans
, root
, ret
);
1854 * interface function to delete all the snapshots we have scheduled for deletion
1856 int btrfs_clean_old_snapshots(struct btrfs_root
*root
)
1859 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1861 spin_lock(&fs_info
->trans_lock
);
1862 list_splice_init(&fs_info
->dead_roots
, &list
);
1863 spin_unlock(&fs_info
->trans_lock
);
1865 while (!list_empty(&list
)) {
1868 root
= list_entry(list
.next
, struct btrfs_root
, root_list
);
1869 list_del(&root
->root_list
);
1871 btrfs_kill_all_delayed_nodes(root
);
1873 if (btrfs_header_backref_rev(root
->node
) <
1874 BTRFS_MIXED_BACKREF_REV
)
1875 ret
= btrfs_drop_snapshot(root
, NULL
, 0, 0);
1877 ret
=btrfs_drop_snapshot(root
, NULL
, 1, 0);