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
);
170 atomic_set(&cur_trans
->delayed_refs
.procs_running_refs
, 0);
171 atomic_set(&cur_trans
->delayed_refs
.ref_seq
, 0);
172 init_waitqueue_head(&cur_trans
->delayed_refs
.wait
);
174 INIT_LIST_HEAD(&cur_trans
->pending_snapshots
);
175 INIT_LIST_HEAD(&cur_trans
->ordered_operations
);
176 list_add_tail(&cur_trans
->list
, &fs_info
->trans_list
);
177 extent_io_tree_init(&cur_trans
->dirty_pages
,
178 fs_info
->btree_inode
->i_mapping
);
179 fs_info
->generation
++;
180 cur_trans
->transid
= fs_info
->generation
;
181 fs_info
->running_transaction
= cur_trans
;
182 cur_trans
->aborted
= 0;
183 spin_unlock(&fs_info
->trans_lock
);
189 * this does all the record keeping required to make sure that a reference
190 * counted root is properly recorded in a given transaction. This is required
191 * to make sure the old root from before we joined the transaction is deleted
192 * when the transaction commits
194 static int record_root_in_trans(struct btrfs_trans_handle
*trans
,
195 struct btrfs_root
*root
)
197 if (root
->ref_cows
&& root
->last_trans
< trans
->transid
) {
198 WARN_ON(root
== root
->fs_info
->extent_root
);
199 WARN_ON(root
->commit_root
!= root
->node
);
202 * see below for in_trans_setup usage rules
203 * we have the reloc mutex held now, so there
204 * is only one writer in this function
206 root
->in_trans_setup
= 1;
208 /* make sure readers find in_trans_setup before
209 * they find our root->last_trans update
213 spin_lock(&root
->fs_info
->fs_roots_radix_lock
);
214 if (root
->last_trans
== trans
->transid
) {
215 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
218 radix_tree_tag_set(&root
->fs_info
->fs_roots_radix
,
219 (unsigned long)root
->root_key
.objectid
,
220 BTRFS_ROOT_TRANS_TAG
);
221 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
222 root
->last_trans
= trans
->transid
;
224 /* this is pretty tricky. We don't want to
225 * take the relocation lock in btrfs_record_root_in_trans
226 * unless we're really doing the first setup for this root in
229 * Normally we'd use root->last_trans as a flag to decide
230 * if we want to take the expensive mutex.
232 * But, we have to set root->last_trans before we
233 * init the relocation root, otherwise, we trip over warnings
234 * in ctree.c. The solution used here is to flag ourselves
235 * with root->in_trans_setup. When this is 1, we're still
236 * fixing up the reloc trees and everyone must wait.
238 * When this is zero, they can trust root->last_trans and fly
239 * through btrfs_record_root_in_trans without having to take the
240 * lock. smp_wmb() makes sure that all the writes above are
241 * done before we pop in the zero below
243 btrfs_init_reloc_root(trans
, root
);
245 root
->in_trans_setup
= 0;
251 int btrfs_record_root_in_trans(struct btrfs_trans_handle
*trans
,
252 struct btrfs_root
*root
)
258 * see record_root_in_trans for comments about in_trans_setup usage
262 if (root
->last_trans
== trans
->transid
&&
263 !root
->in_trans_setup
)
266 mutex_lock(&root
->fs_info
->reloc_mutex
);
267 record_root_in_trans(trans
, root
);
268 mutex_unlock(&root
->fs_info
->reloc_mutex
);
273 /* wait for commit against the current transaction to become unblocked
274 * when this is done, it is safe to start a new transaction, but the current
275 * transaction might not be fully on disk.
277 static void wait_current_trans(struct btrfs_root
*root
)
279 struct btrfs_transaction
*cur_trans
;
281 spin_lock(&root
->fs_info
->trans_lock
);
282 cur_trans
= root
->fs_info
->running_transaction
;
283 if (cur_trans
&& cur_trans
->blocked
) {
284 atomic_inc(&cur_trans
->use_count
);
285 spin_unlock(&root
->fs_info
->trans_lock
);
287 wait_event(root
->fs_info
->transaction_wait
,
288 !cur_trans
->blocked
);
289 put_transaction(cur_trans
);
291 spin_unlock(&root
->fs_info
->trans_lock
);
295 static int may_wait_transaction(struct btrfs_root
*root
, int type
)
297 if (root
->fs_info
->log_root_recovering
)
300 if (type
== TRANS_USERSPACE
)
303 if (type
== TRANS_START
&&
304 !atomic_read(&root
->fs_info
->open_ioctl_trans
))
310 static struct btrfs_trans_handle
*
311 start_transaction(struct btrfs_root
*root
, u64 num_items
, int type
,
312 enum btrfs_reserve_flush_enum flush
)
314 struct btrfs_trans_handle
*h
;
315 struct btrfs_transaction
*cur_trans
;
318 u64 qgroup_reserved
= 0;
320 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
))
321 return ERR_PTR(-EROFS
);
323 if (current
->journal_info
) {
324 WARN_ON(type
!= TRANS_JOIN
&& type
!= TRANS_JOIN_NOLOCK
);
325 h
= current
->journal_info
;
327 WARN_ON(h
->use_count
> 2);
328 h
->orig_rsv
= h
->block_rsv
;
334 * Do the reservation before we join the transaction so we can do all
335 * the appropriate flushing if need be.
337 if (num_items
> 0 && root
!= root
->fs_info
->chunk_root
) {
338 if (root
->fs_info
->quota_enabled
&&
339 is_fstree(root
->root_key
.objectid
)) {
340 qgroup_reserved
= num_items
* root
->leafsize
;
341 ret
= btrfs_qgroup_reserve(root
, qgroup_reserved
);
346 num_bytes
= btrfs_calc_trans_metadata_size(root
, num_items
);
347 ret
= btrfs_block_rsv_add(root
,
348 &root
->fs_info
->trans_block_rsv
,
354 h
= kmem_cache_alloc(btrfs_trans_handle_cachep
, GFP_NOFS
);
361 * If we are JOIN_NOLOCK we're already committing a transaction and
362 * waiting on this guy, so we don't need to do the sb_start_intwrite
363 * because we're already holding a ref. We need this because we could
364 * have raced in and did an fsync() on a file which can kick a commit
365 * and then we deadlock with somebody doing a freeze.
367 * If we are ATTACH, it means we just want to catch the current
368 * transaction and commit it, so we needn't do sb_start_intwrite().
370 if (type
< TRANS_JOIN_NOLOCK
)
371 sb_start_intwrite(root
->fs_info
->sb
);
373 if (may_wait_transaction(root
, type
))
374 wait_current_trans(root
);
377 ret
= join_transaction(root
, type
);
379 wait_current_trans(root
);
380 if (unlikely(type
== TRANS_ATTACH
))
383 } while (ret
== -EBUSY
);
386 /* We must get the transaction if we are JOIN_NOLOCK. */
387 BUG_ON(type
== TRANS_JOIN_NOLOCK
);
391 cur_trans
= root
->fs_info
->running_transaction
;
393 h
->transid
= cur_trans
->transid
;
394 h
->transaction
= cur_trans
;
396 h
->bytes_reserved
= 0;
398 h
->delayed_ref_updates
= 0;
404 h
->qgroup_reserved
= 0;
405 h
->delayed_ref_elem
.seq
= 0;
407 h
->allocating_chunk
= false;
408 INIT_LIST_HEAD(&h
->qgroup_ref_list
);
409 INIT_LIST_HEAD(&h
->new_bgs
);
412 if (cur_trans
->blocked
&& may_wait_transaction(root
, type
)) {
413 btrfs_commit_transaction(h
, root
);
418 trace_btrfs_space_reservation(root
->fs_info
, "transaction",
419 h
->transid
, num_bytes
, 1);
420 h
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
421 h
->bytes_reserved
= num_bytes
;
423 h
->qgroup_reserved
= qgroup_reserved
;
426 btrfs_record_root_in_trans(h
, root
);
428 if (!current
->journal_info
&& type
!= TRANS_USERSPACE
)
429 current
->journal_info
= h
;
433 if (type
< TRANS_JOIN_NOLOCK
)
434 sb_end_intwrite(root
->fs_info
->sb
);
435 kmem_cache_free(btrfs_trans_handle_cachep
, h
);
438 btrfs_block_rsv_release(root
, &root
->fs_info
->trans_block_rsv
,
442 btrfs_qgroup_free(root
, qgroup_reserved
);
446 struct btrfs_trans_handle
*btrfs_start_transaction(struct btrfs_root
*root
,
449 return start_transaction(root
, num_items
, TRANS_START
,
450 BTRFS_RESERVE_FLUSH_ALL
);
453 struct btrfs_trans_handle
*btrfs_start_transaction_lflush(
454 struct btrfs_root
*root
, int num_items
)
456 return start_transaction(root
, num_items
, TRANS_START
,
457 BTRFS_RESERVE_FLUSH_LIMIT
);
460 struct btrfs_trans_handle
*btrfs_join_transaction(struct btrfs_root
*root
)
462 return start_transaction(root
, 0, TRANS_JOIN
, 0);
465 struct btrfs_trans_handle
*btrfs_join_transaction_nolock(struct btrfs_root
*root
)
467 return start_transaction(root
, 0, TRANS_JOIN_NOLOCK
, 0);
470 struct btrfs_trans_handle
*btrfs_start_ioctl_transaction(struct btrfs_root
*root
)
472 return start_transaction(root
, 0, TRANS_USERSPACE
, 0);
476 * btrfs_attach_transaction() - catch the running transaction
478 * It is used when we want to commit the current the transaction, but
479 * don't want to start a new one.
481 * Note: If this function return -ENOENT, it just means there is no
482 * running transaction. But it is possible that the inactive transaction
483 * is still in the memory, not fully on disk. If you hope there is no
484 * inactive transaction in the fs when -ENOENT is returned, you should
486 * btrfs_attach_transaction_barrier()
488 struct btrfs_trans_handle
*btrfs_attach_transaction(struct btrfs_root
*root
)
490 return start_transaction(root
, 0, TRANS_ATTACH
, 0);
494 * btrfs_attach_transaction() - catch the running transaction
496 * It is similar to the above function, the differentia is this one
497 * will wait for all the inactive transactions until they fully
500 struct btrfs_trans_handle
*
501 btrfs_attach_transaction_barrier(struct btrfs_root
*root
)
503 struct btrfs_trans_handle
*trans
;
505 trans
= start_transaction(root
, 0, TRANS_ATTACH
, 0);
506 if (IS_ERR(trans
) && PTR_ERR(trans
) == -ENOENT
)
507 btrfs_wait_for_commit(root
, 0);
512 /* wait for a transaction commit to be fully complete */
513 static noinline
void wait_for_commit(struct btrfs_root
*root
,
514 struct btrfs_transaction
*commit
)
516 wait_event(commit
->commit_wait
, commit
->commit_done
);
519 int btrfs_wait_for_commit(struct btrfs_root
*root
, u64 transid
)
521 struct btrfs_transaction
*cur_trans
= NULL
, *t
;
525 if (transid
<= root
->fs_info
->last_trans_committed
)
529 /* find specified transaction */
530 spin_lock(&root
->fs_info
->trans_lock
);
531 list_for_each_entry(t
, &root
->fs_info
->trans_list
, list
) {
532 if (t
->transid
== transid
) {
534 atomic_inc(&cur_trans
->use_count
);
538 if (t
->transid
> transid
) {
543 spin_unlock(&root
->fs_info
->trans_lock
);
544 /* The specified transaction doesn't exist */
548 /* find newest transaction that is committing | committed */
549 spin_lock(&root
->fs_info
->trans_lock
);
550 list_for_each_entry_reverse(t
, &root
->fs_info
->trans_list
,
556 atomic_inc(&cur_trans
->use_count
);
560 spin_unlock(&root
->fs_info
->trans_lock
);
562 goto out
; /* nothing committing|committed */
565 wait_for_commit(root
, cur_trans
);
566 put_transaction(cur_trans
);
571 void btrfs_throttle(struct btrfs_root
*root
)
573 if (!atomic_read(&root
->fs_info
->open_ioctl_trans
))
574 wait_current_trans(root
);
577 static int should_end_transaction(struct btrfs_trans_handle
*trans
,
578 struct btrfs_root
*root
)
582 ret
= btrfs_block_rsv_check(root
, &root
->fs_info
->global_block_rsv
, 5);
586 int btrfs_should_end_transaction(struct btrfs_trans_handle
*trans
,
587 struct btrfs_root
*root
)
589 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
594 if (cur_trans
->blocked
|| cur_trans
->delayed_refs
.flushing
)
597 updates
= trans
->delayed_ref_updates
;
598 trans
->delayed_ref_updates
= 0;
600 err
= btrfs_run_delayed_refs(trans
, root
, updates
);
601 if (err
) /* Error code will also eval true */
605 return should_end_transaction(trans
, root
);
608 static int __btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
609 struct btrfs_root
*root
, int throttle
)
611 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
612 struct btrfs_fs_info
*info
= root
->fs_info
;
614 int lock
= (trans
->type
!= TRANS_JOIN_NOLOCK
);
617 if (--trans
->use_count
) {
618 trans
->block_rsv
= trans
->orig_rsv
;
623 * do the qgroup accounting as early as possible
625 err
= btrfs_delayed_refs_qgroup_accounting(trans
, info
);
627 btrfs_trans_release_metadata(trans
, root
);
628 trans
->block_rsv
= NULL
;
630 * the same root has to be passed to start_transaction and
631 * end_transaction. Subvolume quota depends on this.
633 WARN_ON(trans
->root
!= root
);
635 if (trans
->qgroup_reserved
) {
636 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
637 trans
->qgroup_reserved
= 0;
640 if (!list_empty(&trans
->new_bgs
))
641 btrfs_create_pending_block_groups(trans
, root
);
644 unsigned long cur
= trans
->delayed_ref_updates
;
645 trans
->delayed_ref_updates
= 0;
647 trans
->transaction
->delayed_refs
.num_heads_ready
> 64) {
648 trans
->delayed_ref_updates
= 0;
649 btrfs_run_delayed_refs(trans
, root
, cur
);
656 btrfs_trans_release_metadata(trans
, root
);
657 trans
->block_rsv
= NULL
;
659 if (!list_empty(&trans
->new_bgs
))
660 btrfs_create_pending_block_groups(trans
, root
);
662 if (lock
&& !atomic_read(&root
->fs_info
->open_ioctl_trans
) &&
663 should_end_transaction(trans
, root
)) {
664 trans
->transaction
->blocked
= 1;
668 if (lock
&& cur_trans
->blocked
&& !cur_trans
->in_commit
) {
671 * We may race with somebody else here so end up having
672 * to call end_transaction on ourselves again, so inc
676 return btrfs_commit_transaction(trans
, root
);
678 wake_up_process(info
->transaction_kthread
);
682 if (trans
->type
< TRANS_JOIN_NOLOCK
)
683 sb_end_intwrite(root
->fs_info
->sb
);
685 WARN_ON(cur_trans
!= info
->running_transaction
);
686 WARN_ON(atomic_read(&cur_trans
->num_writers
) < 1);
687 atomic_dec(&cur_trans
->num_writers
);
690 if (waitqueue_active(&cur_trans
->writer_wait
))
691 wake_up(&cur_trans
->writer_wait
);
692 put_transaction(cur_trans
);
694 if (current
->journal_info
== trans
)
695 current
->journal_info
= NULL
;
698 btrfs_run_delayed_iputs(root
);
700 if (trans
->aborted
||
701 test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
))
703 assert_qgroups_uptodate(trans
);
705 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
709 int btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
710 struct btrfs_root
*root
)
714 ret
= __btrfs_end_transaction(trans
, root
, 0);
720 int btrfs_end_transaction_throttle(struct btrfs_trans_handle
*trans
,
721 struct btrfs_root
*root
)
725 ret
= __btrfs_end_transaction(trans
, root
, 1);
731 int btrfs_end_transaction_dmeta(struct btrfs_trans_handle
*trans
,
732 struct btrfs_root
*root
)
734 return __btrfs_end_transaction(trans
, root
, 1);
738 * when btree blocks are allocated, they have some corresponding bits set for
739 * them in one of two extent_io trees. This is used to make sure all of
740 * those extents are sent to disk but does not wait on them
742 int btrfs_write_marked_extents(struct btrfs_root
*root
,
743 struct extent_io_tree
*dirty_pages
, int mark
)
747 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
748 struct extent_state
*cached_state
= NULL
;
751 struct blk_plug plug
;
753 blk_start_plug(&plug
);
754 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
755 mark
, &cached_state
)) {
756 convert_extent_bit(dirty_pages
, start
, end
, EXTENT_NEED_WAIT
,
757 mark
, &cached_state
, GFP_NOFS
);
759 err
= filemap_fdatawrite_range(mapping
, start
, end
);
767 blk_finish_plug(&plug
);
772 * when btree blocks are allocated, they have some corresponding bits set for
773 * them in one of two extent_io trees. This is used to make sure all of
774 * those extents are on disk for transaction or log commit. We wait
775 * on all the pages and clear them from the dirty pages state tree
777 int btrfs_wait_marked_extents(struct btrfs_root
*root
,
778 struct extent_io_tree
*dirty_pages
, int mark
)
782 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
783 struct extent_state
*cached_state
= NULL
;
787 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
788 EXTENT_NEED_WAIT
, &cached_state
)) {
789 clear_extent_bit(dirty_pages
, start
, end
, EXTENT_NEED_WAIT
,
790 0, 0, &cached_state
, GFP_NOFS
);
791 err
= filemap_fdatawait_range(mapping
, start
, end
);
803 * when btree blocks are allocated, they have some corresponding bits set for
804 * them in one of two extent_io trees. This is used to make sure all of
805 * those extents are on disk for transaction or log commit
807 int btrfs_write_and_wait_marked_extents(struct btrfs_root
*root
,
808 struct extent_io_tree
*dirty_pages
, int mark
)
813 ret
= btrfs_write_marked_extents(root
, dirty_pages
, mark
);
814 ret2
= btrfs_wait_marked_extents(root
, dirty_pages
, mark
);
823 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle
*trans
,
824 struct btrfs_root
*root
)
826 if (!trans
|| !trans
->transaction
) {
827 struct inode
*btree_inode
;
828 btree_inode
= root
->fs_info
->btree_inode
;
829 return filemap_write_and_wait(btree_inode
->i_mapping
);
831 return btrfs_write_and_wait_marked_extents(root
,
832 &trans
->transaction
->dirty_pages
,
837 * this is used to update the root pointer in the tree of tree roots.
839 * But, in the case of the extent allocation tree, updating the root
840 * pointer may allocate blocks which may change the root of the extent
843 * So, this loops and repeats and makes sure the cowonly root didn't
844 * change while the root pointer was being updated in the metadata.
846 static int update_cowonly_root(struct btrfs_trans_handle
*trans
,
847 struct btrfs_root
*root
)
852 struct btrfs_root
*tree_root
= root
->fs_info
->tree_root
;
854 old_root_used
= btrfs_root_used(&root
->root_item
);
855 btrfs_write_dirty_block_groups(trans
, root
);
858 old_root_bytenr
= btrfs_root_bytenr(&root
->root_item
);
859 if (old_root_bytenr
== root
->node
->start
&&
860 old_root_used
== btrfs_root_used(&root
->root_item
))
863 btrfs_set_root_node(&root
->root_item
, root
->node
);
864 ret
= btrfs_update_root(trans
, tree_root
,
870 old_root_used
= btrfs_root_used(&root
->root_item
);
871 ret
= btrfs_write_dirty_block_groups(trans
, root
);
876 if (root
!= root
->fs_info
->extent_root
)
877 switch_commit_root(root
);
883 * update all the cowonly tree roots on disk
885 * The error handling in this function may not be obvious. Any of the
886 * failures will cause the file system to go offline. We still need
887 * to clean up the delayed refs.
889 static noinline
int commit_cowonly_roots(struct btrfs_trans_handle
*trans
,
890 struct btrfs_root
*root
)
892 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
893 struct list_head
*next
;
894 struct extent_buffer
*eb
;
897 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
901 eb
= btrfs_lock_root_node(fs_info
->tree_root
);
902 ret
= btrfs_cow_block(trans
, fs_info
->tree_root
, eb
, NULL
,
904 btrfs_tree_unlock(eb
);
905 free_extent_buffer(eb
);
910 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
914 ret
= btrfs_run_dev_stats(trans
, root
->fs_info
);
916 ret
= btrfs_run_dev_replace(trans
, root
->fs_info
);
919 ret
= btrfs_run_qgroups(trans
, root
->fs_info
);
922 /* run_qgroups might have added some more refs */
923 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
926 while (!list_empty(&fs_info
->dirty_cowonly_roots
)) {
927 next
= fs_info
->dirty_cowonly_roots
.next
;
929 root
= list_entry(next
, struct btrfs_root
, dirty_list
);
931 ret
= update_cowonly_root(trans
, root
);
936 down_write(&fs_info
->extent_commit_sem
);
937 switch_commit_root(fs_info
->extent_root
);
938 up_write(&fs_info
->extent_commit_sem
);
940 btrfs_after_dev_replace_commit(fs_info
);
946 * dead roots are old snapshots that need to be deleted. This allocates
947 * a dirty root struct and adds it into the list of dead roots that need to
950 int btrfs_add_dead_root(struct btrfs_root
*root
)
952 spin_lock(&root
->fs_info
->trans_lock
);
953 list_add(&root
->root_list
, &root
->fs_info
->dead_roots
);
954 spin_unlock(&root
->fs_info
->trans_lock
);
959 * update all the cowonly tree roots on disk
961 static noinline
int commit_fs_roots(struct btrfs_trans_handle
*trans
,
962 struct btrfs_root
*root
)
964 struct btrfs_root
*gang
[8];
965 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
970 spin_lock(&fs_info
->fs_roots_radix_lock
);
972 ret
= radix_tree_gang_lookup_tag(&fs_info
->fs_roots_radix
,
975 BTRFS_ROOT_TRANS_TAG
);
978 for (i
= 0; i
< ret
; i
++) {
980 radix_tree_tag_clear(&fs_info
->fs_roots_radix
,
981 (unsigned long)root
->root_key
.objectid
,
982 BTRFS_ROOT_TRANS_TAG
);
983 spin_unlock(&fs_info
->fs_roots_radix_lock
);
985 btrfs_free_log(trans
, root
);
986 btrfs_update_reloc_root(trans
, root
);
987 btrfs_orphan_commit_root(trans
, root
);
989 btrfs_save_ino_cache(root
, trans
);
991 /* see comments in should_cow_block() */
995 if (root
->commit_root
!= root
->node
) {
996 mutex_lock(&root
->fs_commit_mutex
);
997 switch_commit_root(root
);
998 btrfs_unpin_free_ino(root
);
999 mutex_unlock(&root
->fs_commit_mutex
);
1001 btrfs_set_root_node(&root
->root_item
,
1005 err
= btrfs_update_root(trans
, fs_info
->tree_root
,
1008 spin_lock(&fs_info
->fs_roots_radix_lock
);
1013 spin_unlock(&fs_info
->fs_roots_radix_lock
);
1018 * defrag a given btree.
1019 * Every leaf in the btree is read and defragged.
1021 int btrfs_defrag_root(struct btrfs_root
*root
)
1023 struct btrfs_fs_info
*info
= root
->fs_info
;
1024 struct btrfs_trans_handle
*trans
;
1027 if (xchg(&root
->defrag_running
, 1))
1031 trans
= btrfs_start_transaction(root
, 0);
1033 return PTR_ERR(trans
);
1035 ret
= btrfs_defrag_leaves(trans
, root
);
1037 btrfs_end_transaction(trans
, root
);
1038 btrfs_btree_balance_dirty(info
->tree_root
);
1041 if (btrfs_fs_closing(root
->fs_info
) || ret
!= -EAGAIN
)
1044 if (btrfs_defrag_cancelled(root
->fs_info
)) {
1045 printk(KERN_DEBUG
"btrfs: defrag_root cancelled\n");
1050 root
->defrag_running
= 0;
1055 * new snapshots need to be created at a very specific time in the
1056 * transaction commit. This does the actual creation
1058 static noinline
int create_pending_snapshot(struct btrfs_trans_handle
*trans
,
1059 struct btrfs_fs_info
*fs_info
,
1060 struct btrfs_pending_snapshot
*pending
)
1062 struct btrfs_key key
;
1063 struct btrfs_root_item
*new_root_item
;
1064 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
1065 struct btrfs_root
*root
= pending
->root
;
1066 struct btrfs_root
*parent_root
;
1067 struct btrfs_block_rsv
*rsv
;
1068 struct inode
*parent_inode
;
1069 struct btrfs_path
*path
;
1070 struct btrfs_dir_item
*dir_item
;
1071 struct dentry
*parent
;
1072 struct dentry
*dentry
;
1073 struct extent_buffer
*tmp
;
1074 struct extent_buffer
*old
;
1075 struct timespec cur_time
= CURRENT_TIME
;
1083 path
= btrfs_alloc_path();
1085 ret
= pending
->error
= -ENOMEM
;
1086 goto path_alloc_fail
;
1089 new_root_item
= kmalloc(sizeof(*new_root_item
), GFP_NOFS
);
1090 if (!new_root_item
) {
1091 ret
= pending
->error
= -ENOMEM
;
1092 goto root_item_alloc_fail
;
1095 ret
= btrfs_find_free_objectid(tree_root
, &objectid
);
1097 pending
->error
= ret
;
1098 goto no_free_objectid
;
1101 btrfs_reloc_pre_snapshot(trans
, pending
, &to_reserve
);
1103 if (to_reserve
> 0) {
1104 ret
= btrfs_block_rsv_add(root
, &pending
->block_rsv
,
1106 BTRFS_RESERVE_NO_FLUSH
);
1108 pending
->error
= ret
;
1109 goto no_free_objectid
;
1113 ret
= btrfs_qgroup_inherit(trans
, fs_info
, root
->root_key
.objectid
,
1114 objectid
, pending
->inherit
);
1116 pending
->error
= ret
;
1117 goto no_free_objectid
;
1120 key
.objectid
= objectid
;
1121 key
.offset
= (u64
)-1;
1122 key
.type
= BTRFS_ROOT_ITEM_KEY
;
1124 rsv
= trans
->block_rsv
;
1125 trans
->block_rsv
= &pending
->block_rsv
;
1127 dentry
= pending
->dentry
;
1128 parent
= dget_parent(dentry
);
1129 parent_inode
= parent
->d_inode
;
1130 parent_root
= BTRFS_I(parent_inode
)->root
;
1131 record_root_in_trans(trans
, parent_root
);
1134 * insert the directory item
1136 ret
= btrfs_set_inode_index(parent_inode
, &index
);
1137 BUG_ON(ret
); /* -ENOMEM */
1139 /* check if there is a file/dir which has the same name. */
1140 dir_item
= btrfs_lookup_dir_item(NULL
, parent_root
, path
,
1141 btrfs_ino(parent_inode
),
1142 dentry
->d_name
.name
,
1143 dentry
->d_name
.len
, 0);
1144 if (dir_item
!= NULL
&& !IS_ERR(dir_item
)) {
1145 pending
->error
= -EEXIST
;
1147 } else if (IS_ERR(dir_item
)) {
1148 ret
= PTR_ERR(dir_item
);
1149 btrfs_abort_transaction(trans
, root
, ret
);
1152 btrfs_release_path(path
);
1155 * pull in the delayed directory update
1156 * and the delayed inode item
1157 * otherwise we corrupt the FS during
1160 ret
= btrfs_run_delayed_items(trans
, root
);
1161 if (ret
) { /* Transaction aborted */
1162 btrfs_abort_transaction(trans
, root
, ret
);
1166 record_root_in_trans(trans
, root
);
1167 btrfs_set_root_last_snapshot(&root
->root_item
, trans
->transid
);
1168 memcpy(new_root_item
, &root
->root_item
, sizeof(*new_root_item
));
1169 btrfs_check_and_init_root_item(new_root_item
);
1171 root_flags
= btrfs_root_flags(new_root_item
);
1172 if (pending
->readonly
)
1173 root_flags
|= BTRFS_ROOT_SUBVOL_RDONLY
;
1175 root_flags
&= ~BTRFS_ROOT_SUBVOL_RDONLY
;
1176 btrfs_set_root_flags(new_root_item
, root_flags
);
1178 btrfs_set_root_generation_v2(new_root_item
,
1180 uuid_le_gen(&new_uuid
);
1181 memcpy(new_root_item
->uuid
, new_uuid
.b
, BTRFS_UUID_SIZE
);
1182 memcpy(new_root_item
->parent_uuid
, root
->root_item
.uuid
,
1184 new_root_item
->otime
.sec
= cpu_to_le64(cur_time
.tv_sec
);
1185 new_root_item
->otime
.nsec
= cpu_to_le32(cur_time
.tv_nsec
);
1186 btrfs_set_root_otransid(new_root_item
, trans
->transid
);
1187 memset(&new_root_item
->stime
, 0, sizeof(new_root_item
->stime
));
1188 memset(&new_root_item
->rtime
, 0, sizeof(new_root_item
->rtime
));
1189 btrfs_set_root_stransid(new_root_item
, 0);
1190 btrfs_set_root_rtransid(new_root_item
, 0);
1192 old
= btrfs_lock_root_node(root
);
1193 ret
= btrfs_cow_block(trans
, root
, old
, NULL
, 0, &old
);
1195 btrfs_tree_unlock(old
);
1196 free_extent_buffer(old
);
1197 btrfs_abort_transaction(trans
, root
, ret
);
1201 btrfs_set_lock_blocking(old
);
1203 ret
= btrfs_copy_root(trans
, root
, old
, &tmp
, objectid
);
1204 /* clean up in any case */
1205 btrfs_tree_unlock(old
);
1206 free_extent_buffer(old
);
1208 btrfs_abort_transaction(trans
, root
, ret
);
1212 /* see comments in should_cow_block() */
1213 root
->force_cow
= 1;
1216 btrfs_set_root_node(new_root_item
, tmp
);
1217 /* record when the snapshot was created in key.offset */
1218 key
.offset
= trans
->transid
;
1219 ret
= btrfs_insert_root(trans
, tree_root
, &key
, new_root_item
);
1220 btrfs_tree_unlock(tmp
);
1221 free_extent_buffer(tmp
);
1223 btrfs_abort_transaction(trans
, root
, ret
);
1228 * insert root back/forward references
1230 ret
= btrfs_add_root_ref(trans
, tree_root
, objectid
,
1231 parent_root
->root_key
.objectid
,
1232 btrfs_ino(parent_inode
), index
,
1233 dentry
->d_name
.name
, dentry
->d_name
.len
);
1235 btrfs_abort_transaction(trans
, root
, ret
);
1239 key
.offset
= (u64
)-1;
1240 pending
->snap
= btrfs_read_fs_root_no_name(root
->fs_info
, &key
);
1241 if (IS_ERR(pending
->snap
)) {
1242 ret
= PTR_ERR(pending
->snap
);
1243 btrfs_abort_transaction(trans
, root
, ret
);
1247 ret
= btrfs_reloc_post_snapshot(trans
, pending
);
1249 btrfs_abort_transaction(trans
, root
, ret
);
1253 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1255 btrfs_abort_transaction(trans
, root
, ret
);
1259 ret
= btrfs_insert_dir_item(trans
, parent_root
,
1260 dentry
->d_name
.name
, dentry
->d_name
.len
,
1262 BTRFS_FT_DIR
, index
);
1263 /* We have check then name at the beginning, so it is impossible. */
1264 BUG_ON(ret
== -EEXIST
|| ret
== -EOVERFLOW
);
1266 btrfs_abort_transaction(trans
, root
, ret
);
1270 btrfs_i_size_write(parent_inode
, parent_inode
->i_size
+
1271 dentry
->d_name
.len
* 2);
1272 parent_inode
->i_mtime
= parent_inode
->i_ctime
= CURRENT_TIME
;
1273 ret
= btrfs_update_inode_fallback(trans
, parent_root
, parent_inode
);
1275 btrfs_abort_transaction(trans
, root
, ret
);
1278 trans
->block_rsv
= rsv
;
1280 kfree(new_root_item
);
1281 root_item_alloc_fail
:
1282 btrfs_free_path(path
);
1284 btrfs_block_rsv_release(root
, &pending
->block_rsv
, (u64
)-1);
1289 * create all the snapshots we've scheduled for creation
1291 static noinline
int create_pending_snapshots(struct btrfs_trans_handle
*trans
,
1292 struct btrfs_fs_info
*fs_info
)
1294 struct btrfs_pending_snapshot
*pending
;
1295 struct list_head
*head
= &trans
->transaction
->pending_snapshots
;
1297 list_for_each_entry(pending
, head
, list
)
1298 create_pending_snapshot(trans
, fs_info
, pending
);
1302 static void update_super_roots(struct btrfs_root
*root
)
1304 struct btrfs_root_item
*root_item
;
1305 struct btrfs_super_block
*super
;
1307 super
= root
->fs_info
->super_copy
;
1309 root_item
= &root
->fs_info
->chunk_root
->root_item
;
1310 super
->chunk_root
= root_item
->bytenr
;
1311 super
->chunk_root_generation
= root_item
->generation
;
1312 super
->chunk_root_level
= root_item
->level
;
1314 root_item
= &root
->fs_info
->tree_root
->root_item
;
1315 super
->root
= root_item
->bytenr
;
1316 super
->generation
= root_item
->generation
;
1317 super
->root_level
= root_item
->level
;
1318 if (btrfs_test_opt(root
, SPACE_CACHE
))
1319 super
->cache_generation
= root_item
->generation
;
1322 int btrfs_transaction_in_commit(struct btrfs_fs_info
*info
)
1325 spin_lock(&info
->trans_lock
);
1326 if (info
->running_transaction
)
1327 ret
= info
->running_transaction
->in_commit
;
1328 spin_unlock(&info
->trans_lock
);
1332 int btrfs_transaction_blocked(struct btrfs_fs_info
*info
)
1335 spin_lock(&info
->trans_lock
);
1336 if (info
->running_transaction
)
1337 ret
= info
->running_transaction
->blocked
;
1338 spin_unlock(&info
->trans_lock
);
1343 * wait for the current transaction commit to start and block subsequent
1346 static void wait_current_trans_commit_start(struct btrfs_root
*root
,
1347 struct btrfs_transaction
*trans
)
1349 wait_event(root
->fs_info
->transaction_blocked_wait
, trans
->in_commit
);
1353 * wait for the current transaction to start and then become unblocked.
1356 static void wait_current_trans_commit_start_and_unblock(struct btrfs_root
*root
,
1357 struct btrfs_transaction
*trans
)
1359 wait_event(root
->fs_info
->transaction_wait
,
1360 trans
->commit_done
|| (trans
->in_commit
&& !trans
->blocked
));
1364 * commit transactions asynchronously. once btrfs_commit_transaction_async
1365 * returns, any subsequent transaction will not be allowed to join.
1367 struct btrfs_async_commit
{
1368 struct btrfs_trans_handle
*newtrans
;
1369 struct btrfs_root
*root
;
1370 struct work_struct work
;
1373 static void do_async_commit(struct work_struct
*work
)
1375 struct btrfs_async_commit
*ac
=
1376 container_of(work
, struct btrfs_async_commit
, work
);
1379 * We've got freeze protection passed with the transaction.
1380 * Tell lockdep about it.
1382 if (ac
->newtrans
->type
< TRANS_JOIN_NOLOCK
)
1384 &ac
->root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1387 current
->journal_info
= ac
->newtrans
;
1389 btrfs_commit_transaction(ac
->newtrans
, ac
->root
);
1393 int btrfs_commit_transaction_async(struct btrfs_trans_handle
*trans
,
1394 struct btrfs_root
*root
,
1395 int wait_for_unblock
)
1397 struct btrfs_async_commit
*ac
;
1398 struct btrfs_transaction
*cur_trans
;
1400 ac
= kmalloc(sizeof(*ac
), GFP_NOFS
);
1404 INIT_WORK(&ac
->work
, do_async_commit
);
1406 ac
->newtrans
= btrfs_join_transaction(root
);
1407 if (IS_ERR(ac
->newtrans
)) {
1408 int err
= PTR_ERR(ac
->newtrans
);
1413 /* take transaction reference */
1414 cur_trans
= trans
->transaction
;
1415 atomic_inc(&cur_trans
->use_count
);
1417 btrfs_end_transaction(trans
, root
);
1420 * Tell lockdep we've released the freeze rwsem, since the
1421 * async commit thread will be the one to unlock it.
1423 if (trans
->type
< TRANS_JOIN_NOLOCK
)
1425 &root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1428 schedule_work(&ac
->work
);
1430 /* wait for transaction to start and unblock */
1431 if (wait_for_unblock
)
1432 wait_current_trans_commit_start_and_unblock(root
, cur_trans
);
1434 wait_current_trans_commit_start(root
, cur_trans
);
1436 if (current
->journal_info
== trans
)
1437 current
->journal_info
= NULL
;
1439 put_transaction(cur_trans
);
1444 static void cleanup_transaction(struct btrfs_trans_handle
*trans
,
1445 struct btrfs_root
*root
, int err
)
1447 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1449 WARN_ON(trans
->use_count
> 1);
1451 btrfs_abort_transaction(trans
, root
, err
);
1453 spin_lock(&root
->fs_info
->trans_lock
);
1454 list_del_init(&cur_trans
->list
);
1455 if (cur_trans
== root
->fs_info
->running_transaction
) {
1456 root
->fs_info
->running_transaction
= NULL
;
1457 root
->fs_info
->trans_no_join
= 0;
1459 spin_unlock(&root
->fs_info
->trans_lock
);
1461 btrfs_cleanup_one_transaction(trans
->transaction
, root
);
1463 put_transaction(cur_trans
);
1464 put_transaction(cur_trans
);
1466 trace_btrfs_transaction_commit(root
);
1468 btrfs_scrub_continue(root
);
1470 if (current
->journal_info
== trans
)
1471 current
->journal_info
= NULL
;
1473 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
1476 static int btrfs_flush_all_pending_stuffs(struct btrfs_trans_handle
*trans
,
1477 struct btrfs_root
*root
)
1479 int flush_on_commit
= btrfs_test_opt(root
, FLUSHONCOMMIT
);
1480 int snap_pending
= 0;
1483 if (!flush_on_commit
) {
1484 spin_lock(&root
->fs_info
->trans_lock
);
1485 if (!list_empty(&trans
->transaction
->pending_snapshots
))
1487 spin_unlock(&root
->fs_info
->trans_lock
);
1490 if (flush_on_commit
|| snap_pending
) {
1491 ret
= btrfs_start_delalloc_inodes(root
, 1);
1494 btrfs_wait_ordered_extents(root
, 1);
1497 ret
= btrfs_run_delayed_items(trans
, root
);
1502 * running the delayed items may have added new refs. account
1503 * them now so that they hinder processing of more delayed refs
1504 * as little as possible.
1506 btrfs_delayed_refs_qgroup_accounting(trans
, root
->fs_info
);
1509 * rename don't use btrfs_join_transaction, so, once we
1510 * set the transaction to blocked above, we aren't going
1511 * to get any new ordered operations. We can safely run
1512 * it here and no for sure that nothing new will be added
1515 ret
= btrfs_run_ordered_operations(trans
, root
, 1);
1521 * btrfs_transaction state sequence:
1522 * in_commit = 0, blocked = 0 (initial)
1523 * in_commit = 1, blocked = 1
1527 int btrfs_commit_transaction(struct btrfs_trans_handle
*trans
,
1528 struct btrfs_root
*root
)
1530 unsigned long joined
= 0;
1531 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1532 struct btrfs_transaction
*prev_trans
= NULL
;
1535 int should_grow
= 0;
1536 unsigned long now
= get_seconds();
1538 ret
= btrfs_run_ordered_operations(trans
, root
, 0);
1540 btrfs_abort_transaction(trans
, root
, ret
);
1541 btrfs_end_transaction(trans
, root
);
1545 /* Stop the commit early if ->aborted is set */
1546 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1547 ret
= cur_trans
->aborted
;
1548 btrfs_end_transaction(trans
, root
);
1552 /* make a pass through all the delayed refs we have so far
1553 * any runnings procs may add more while we are here
1555 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1557 btrfs_end_transaction(trans
, root
);
1561 btrfs_trans_release_metadata(trans
, root
);
1562 trans
->block_rsv
= NULL
;
1563 if (trans
->qgroup_reserved
) {
1564 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
1565 trans
->qgroup_reserved
= 0;
1568 cur_trans
= trans
->transaction
;
1571 * set the flushing flag so procs in this transaction have to
1572 * start sending their work down.
1574 cur_trans
->delayed_refs
.flushing
= 1;
1576 if (!list_empty(&trans
->new_bgs
))
1577 btrfs_create_pending_block_groups(trans
, root
);
1579 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1581 btrfs_end_transaction(trans
, root
);
1585 spin_lock(&cur_trans
->commit_lock
);
1586 if (cur_trans
->in_commit
) {
1587 spin_unlock(&cur_trans
->commit_lock
);
1588 atomic_inc(&cur_trans
->use_count
);
1589 ret
= btrfs_end_transaction(trans
, root
);
1591 wait_for_commit(root
, cur_trans
);
1593 put_transaction(cur_trans
);
1598 trans
->transaction
->in_commit
= 1;
1599 trans
->transaction
->blocked
= 1;
1600 spin_unlock(&cur_trans
->commit_lock
);
1601 wake_up(&root
->fs_info
->transaction_blocked_wait
);
1603 spin_lock(&root
->fs_info
->trans_lock
);
1604 if (cur_trans
->list
.prev
!= &root
->fs_info
->trans_list
) {
1605 prev_trans
= list_entry(cur_trans
->list
.prev
,
1606 struct btrfs_transaction
, list
);
1607 if (!prev_trans
->commit_done
) {
1608 atomic_inc(&prev_trans
->use_count
);
1609 spin_unlock(&root
->fs_info
->trans_lock
);
1611 wait_for_commit(root
, prev_trans
);
1613 put_transaction(prev_trans
);
1615 spin_unlock(&root
->fs_info
->trans_lock
);
1618 spin_unlock(&root
->fs_info
->trans_lock
);
1621 if (!btrfs_test_opt(root
, SSD
) &&
1622 (now
< cur_trans
->start_time
|| now
- cur_trans
->start_time
< 1))
1626 joined
= cur_trans
->num_joined
;
1628 WARN_ON(cur_trans
!= trans
->transaction
);
1630 ret
= btrfs_flush_all_pending_stuffs(trans
, root
);
1632 goto cleanup_transaction
;
1634 prepare_to_wait(&cur_trans
->writer_wait
, &wait
,
1635 TASK_UNINTERRUPTIBLE
);
1637 if (atomic_read(&cur_trans
->num_writers
) > 1)
1638 schedule_timeout(MAX_SCHEDULE_TIMEOUT
);
1639 else if (should_grow
)
1640 schedule_timeout(1);
1642 finish_wait(&cur_trans
->writer_wait
, &wait
);
1643 } while (atomic_read(&cur_trans
->num_writers
) > 1 ||
1644 (should_grow
&& cur_trans
->num_joined
!= joined
));
1646 ret
= btrfs_flush_all_pending_stuffs(trans
, root
);
1648 goto cleanup_transaction
;
1651 * Ok now we need to make sure to block out any other joins while we
1652 * commit the transaction. We could have started a join before setting
1653 * no_join so make sure to wait for num_writers to == 1 again.
1655 spin_lock(&root
->fs_info
->trans_lock
);
1656 root
->fs_info
->trans_no_join
= 1;
1657 spin_unlock(&root
->fs_info
->trans_lock
);
1658 wait_event(cur_trans
->writer_wait
,
1659 atomic_read(&cur_trans
->num_writers
) == 1);
1661 /* ->aborted might be set after the previous check, so check it */
1662 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1663 ret
= cur_trans
->aborted
;
1664 goto cleanup_transaction
;
1667 * the reloc mutex makes sure that we stop
1668 * the balancing code from coming in and moving
1669 * extents around in the middle of the commit
1671 mutex_lock(&root
->fs_info
->reloc_mutex
);
1674 * We needn't worry about the delayed items because we will
1675 * deal with them in create_pending_snapshot(), which is the
1676 * core function of the snapshot creation.
1678 ret
= create_pending_snapshots(trans
, root
->fs_info
);
1680 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1681 goto cleanup_transaction
;
1685 * We insert the dir indexes of the snapshots and update the inode
1686 * of the snapshots' parents after the snapshot creation, so there
1687 * are some delayed items which are not dealt with. Now deal with
1690 * We needn't worry that this operation will corrupt the snapshots,
1691 * because all the tree which are snapshoted will be forced to COW
1692 * the nodes and leaves.
1694 ret
= btrfs_run_delayed_items(trans
, root
);
1696 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1697 goto cleanup_transaction
;
1700 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1702 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1703 goto cleanup_transaction
;
1707 * make sure none of the code above managed to slip in a
1710 btrfs_assert_delayed_root_empty(root
);
1712 WARN_ON(cur_trans
!= trans
->transaction
);
1714 btrfs_scrub_pause(root
);
1715 /* btrfs_commit_tree_roots is responsible for getting the
1716 * various roots consistent with each other. Every pointer
1717 * in the tree of tree roots has to point to the most up to date
1718 * root for every subvolume and other tree. So, we have to keep
1719 * the tree logging code from jumping in and changing any
1722 * At this point in the commit, there can't be any tree-log
1723 * writers, but a little lower down we drop the trans mutex
1724 * and let new people in. By holding the tree_log_mutex
1725 * from now until after the super is written, we avoid races
1726 * with the tree-log code.
1728 mutex_lock(&root
->fs_info
->tree_log_mutex
);
1730 ret
= commit_fs_roots(trans
, root
);
1732 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1733 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1734 goto cleanup_transaction
;
1737 /* commit_fs_roots gets rid of all the tree log roots, it is now
1738 * safe to free the root of tree log roots
1740 btrfs_free_log_root_tree(trans
, root
->fs_info
);
1742 ret
= commit_cowonly_roots(trans
, root
);
1744 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1745 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1746 goto cleanup_transaction
;
1750 * The tasks which save the space cache and inode cache may also
1751 * update ->aborted, check it.
1753 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1754 ret
= cur_trans
->aborted
;
1755 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1756 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1757 goto cleanup_transaction
;
1760 btrfs_prepare_extent_commit(trans
, root
);
1762 cur_trans
= root
->fs_info
->running_transaction
;
1764 btrfs_set_root_node(&root
->fs_info
->tree_root
->root_item
,
1765 root
->fs_info
->tree_root
->node
);
1766 switch_commit_root(root
->fs_info
->tree_root
);
1768 btrfs_set_root_node(&root
->fs_info
->chunk_root
->root_item
,
1769 root
->fs_info
->chunk_root
->node
);
1770 switch_commit_root(root
->fs_info
->chunk_root
);
1772 assert_qgroups_uptodate(trans
);
1773 update_super_roots(root
);
1775 if (!root
->fs_info
->log_root_recovering
) {
1776 btrfs_set_super_log_root(root
->fs_info
->super_copy
, 0);
1777 btrfs_set_super_log_root_level(root
->fs_info
->super_copy
, 0);
1780 memcpy(root
->fs_info
->super_for_commit
, root
->fs_info
->super_copy
,
1781 sizeof(*root
->fs_info
->super_copy
));
1783 trans
->transaction
->blocked
= 0;
1784 spin_lock(&root
->fs_info
->trans_lock
);
1785 root
->fs_info
->running_transaction
= NULL
;
1786 root
->fs_info
->trans_no_join
= 0;
1787 spin_unlock(&root
->fs_info
->trans_lock
);
1788 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1790 wake_up(&root
->fs_info
->transaction_wait
);
1792 ret
= btrfs_write_and_wait_transaction(trans
, root
);
1794 btrfs_error(root
->fs_info
, ret
,
1795 "Error while writing out transaction.");
1796 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1797 goto cleanup_transaction
;
1800 ret
= write_ctree_super(trans
, root
, 0);
1802 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1803 goto cleanup_transaction
;
1807 * the super is written, we can safely allow the tree-loggers
1808 * to go about their business
1810 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1812 btrfs_finish_extent_commit(trans
, root
);
1814 cur_trans
->commit_done
= 1;
1816 root
->fs_info
->last_trans_committed
= cur_trans
->transid
;
1818 wake_up(&cur_trans
->commit_wait
);
1820 spin_lock(&root
->fs_info
->trans_lock
);
1821 list_del_init(&cur_trans
->list
);
1822 spin_unlock(&root
->fs_info
->trans_lock
);
1824 put_transaction(cur_trans
);
1825 put_transaction(cur_trans
);
1827 if (trans
->type
< TRANS_JOIN_NOLOCK
)
1828 sb_end_intwrite(root
->fs_info
->sb
);
1830 trace_btrfs_transaction_commit(root
);
1832 btrfs_scrub_continue(root
);
1834 if (current
->journal_info
== trans
)
1835 current
->journal_info
= NULL
;
1837 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
1839 if (current
!= root
->fs_info
->transaction_kthread
)
1840 btrfs_run_delayed_iputs(root
);
1844 cleanup_transaction
:
1845 btrfs_trans_release_metadata(trans
, root
);
1846 trans
->block_rsv
= NULL
;
1847 if (trans
->qgroup_reserved
) {
1848 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
1849 trans
->qgroup_reserved
= 0;
1851 btrfs_printk(root
->fs_info
, "Skipping commit of aborted transaction.\n");
1853 if (current
->journal_info
== trans
)
1854 current
->journal_info
= NULL
;
1855 cleanup_transaction(trans
, root
, ret
);
1861 * interface function to delete all the snapshots we have scheduled for deletion
1863 int btrfs_clean_old_snapshots(struct btrfs_root
*root
)
1866 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1868 spin_lock(&fs_info
->trans_lock
);
1869 list_splice_init(&fs_info
->dead_roots
, &list
);
1870 spin_unlock(&fs_info
->trans_lock
);
1872 while (!list_empty(&list
)) {
1875 root
= list_entry(list
.next
, struct btrfs_root
, root_list
);
1876 list_del(&root
->root_list
);
1878 btrfs_kill_all_delayed_nodes(root
);
1880 if (btrfs_header_backref_rev(root
->node
) <
1881 BTRFS_MIXED_BACKREF_REV
)
1882 ret
= btrfs_drop_snapshot(root
, NULL
, 0, 0);
1884 ret
=btrfs_drop_snapshot(root
, NULL
, 1, 0);