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"
36 #define BTRFS_ROOT_TRANS_TAG 0
38 static unsigned int btrfs_blocked_trans_types
[TRANS_STATE_MAX
] = {
39 [TRANS_STATE_RUNNING
] = 0U,
40 [TRANS_STATE_BLOCKED
] = (__TRANS_USERSPACE
|
42 [TRANS_STATE_COMMIT_START
] = (__TRANS_USERSPACE
|
45 [TRANS_STATE_COMMIT_DOING
] = (__TRANS_USERSPACE
|
49 [TRANS_STATE_UNBLOCKED
] = (__TRANS_USERSPACE
|
54 [TRANS_STATE_COMPLETED
] = (__TRANS_USERSPACE
|
61 void btrfs_put_transaction(struct btrfs_transaction
*transaction
)
63 WARN_ON(atomic_read(&transaction
->use_count
) == 0);
64 if (atomic_dec_and_test(&transaction
->use_count
)) {
65 BUG_ON(!list_empty(&transaction
->list
));
66 WARN_ON(!RB_EMPTY_ROOT(&transaction
->delayed_refs
.href_root
));
67 while (!list_empty(&transaction
->pending_chunks
)) {
68 struct extent_map
*em
;
70 em
= list_first_entry(&transaction
->pending_chunks
,
71 struct extent_map
, list
);
72 list_del_init(&em
->list
);
75 kmem_cache_free(btrfs_transaction_cachep
, transaction
);
79 static void clear_btree_io_tree(struct extent_io_tree
*tree
)
81 spin_lock(&tree
->lock
);
82 while (!RB_EMPTY_ROOT(&tree
->state
)) {
84 struct extent_state
*state
;
86 node
= rb_first(&tree
->state
);
87 state
= rb_entry(node
, struct extent_state
, rb_node
);
88 rb_erase(&state
->rb_node
, &tree
->state
);
89 RB_CLEAR_NODE(&state
->rb_node
);
91 * btree io trees aren't supposed to have tasks waiting for
92 * changes in the flags of extent states ever.
94 ASSERT(!waitqueue_active(&state
->wq
));
95 free_extent_state(state
);
97 spin_unlock(&tree
->lock
);
99 spin_lock(&tree
->lock
);
102 spin_unlock(&tree
->lock
);
105 static noinline
void switch_commit_roots(struct btrfs_transaction
*trans
,
106 struct btrfs_fs_info
*fs_info
)
108 struct btrfs_root
*root
, *tmp
;
110 down_write(&fs_info
->commit_root_sem
);
111 list_for_each_entry_safe(root
, tmp
, &trans
->switch_commits
,
113 list_del_init(&root
->dirty_list
);
114 free_extent_buffer(root
->commit_root
);
115 root
->commit_root
= btrfs_root_node(root
);
116 if (is_fstree(root
->objectid
))
117 btrfs_unpin_free_ino(root
);
118 clear_btree_io_tree(&root
->dirty_log_pages
);
120 up_write(&fs_info
->commit_root_sem
);
123 static inline void extwriter_counter_inc(struct btrfs_transaction
*trans
,
126 if (type
& TRANS_EXTWRITERS
)
127 atomic_inc(&trans
->num_extwriters
);
130 static inline void extwriter_counter_dec(struct btrfs_transaction
*trans
,
133 if (type
& TRANS_EXTWRITERS
)
134 atomic_dec(&trans
->num_extwriters
);
137 static inline void extwriter_counter_init(struct btrfs_transaction
*trans
,
140 atomic_set(&trans
->num_extwriters
, ((type
& TRANS_EXTWRITERS
) ? 1 : 0));
143 static inline int extwriter_counter_read(struct btrfs_transaction
*trans
)
145 return atomic_read(&trans
->num_extwriters
);
149 * either allocate a new transaction or hop into the existing one
151 static noinline
int join_transaction(struct btrfs_root
*root
, unsigned int type
)
153 struct btrfs_transaction
*cur_trans
;
154 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
156 spin_lock(&fs_info
->trans_lock
);
158 /* The file system has been taken offline. No new transactions. */
159 if (test_bit(BTRFS_FS_STATE_ERROR
, &fs_info
->fs_state
)) {
160 spin_unlock(&fs_info
->trans_lock
);
164 cur_trans
= fs_info
->running_transaction
;
166 if (cur_trans
->aborted
) {
167 spin_unlock(&fs_info
->trans_lock
);
168 return cur_trans
->aborted
;
170 if (btrfs_blocked_trans_types
[cur_trans
->state
] & type
) {
171 spin_unlock(&fs_info
->trans_lock
);
174 atomic_inc(&cur_trans
->use_count
);
175 atomic_inc(&cur_trans
->num_writers
);
176 extwriter_counter_inc(cur_trans
, type
);
177 spin_unlock(&fs_info
->trans_lock
);
180 spin_unlock(&fs_info
->trans_lock
);
183 * If we are ATTACH, we just want to catch the current transaction,
184 * and commit it. If there is no transaction, just return ENOENT.
186 if (type
== TRANS_ATTACH
)
190 * JOIN_NOLOCK only happens during the transaction commit, so
191 * it is impossible that ->running_transaction is NULL
193 BUG_ON(type
== TRANS_JOIN_NOLOCK
);
195 cur_trans
= kmem_cache_alloc(btrfs_transaction_cachep
, GFP_NOFS
);
199 spin_lock(&fs_info
->trans_lock
);
200 if (fs_info
->running_transaction
) {
202 * someone started a transaction after we unlocked. Make sure
203 * to redo the checks above
205 kmem_cache_free(btrfs_transaction_cachep
, cur_trans
);
207 } else if (test_bit(BTRFS_FS_STATE_ERROR
, &fs_info
->fs_state
)) {
208 spin_unlock(&fs_info
->trans_lock
);
209 kmem_cache_free(btrfs_transaction_cachep
, cur_trans
);
213 atomic_set(&cur_trans
->num_writers
, 1);
214 extwriter_counter_init(cur_trans
, type
);
215 init_waitqueue_head(&cur_trans
->writer_wait
);
216 init_waitqueue_head(&cur_trans
->commit_wait
);
217 cur_trans
->state
= TRANS_STATE_RUNNING
;
219 * One for this trans handle, one so it will live on until we
220 * commit the transaction.
222 atomic_set(&cur_trans
->use_count
, 2);
223 cur_trans
->start_time
= get_seconds();
225 cur_trans
->delayed_refs
.href_root
= RB_ROOT
;
226 atomic_set(&cur_trans
->delayed_refs
.num_entries
, 0);
227 cur_trans
->delayed_refs
.num_heads_ready
= 0;
228 cur_trans
->delayed_refs
.num_heads
= 0;
229 cur_trans
->delayed_refs
.flushing
= 0;
230 cur_trans
->delayed_refs
.run_delayed_start
= 0;
233 * although the tree mod log is per file system and not per transaction,
234 * the log must never go across transaction boundaries.
237 if (!list_empty(&fs_info
->tree_mod_seq_list
))
238 WARN(1, KERN_ERR
"BTRFS: tree_mod_seq_list not empty when "
239 "creating a fresh transaction\n");
240 if (!RB_EMPTY_ROOT(&fs_info
->tree_mod_log
))
241 WARN(1, KERN_ERR
"BTRFS: tree_mod_log rb tree not empty when "
242 "creating a fresh transaction\n");
243 atomic64_set(&fs_info
->tree_mod_seq
, 0);
245 spin_lock_init(&cur_trans
->delayed_refs
.lock
);
247 INIT_LIST_HEAD(&cur_trans
->pending_snapshots
);
248 INIT_LIST_HEAD(&cur_trans
->pending_chunks
);
249 INIT_LIST_HEAD(&cur_trans
->switch_commits
);
250 INIT_LIST_HEAD(&cur_trans
->pending_ordered
);
251 list_add_tail(&cur_trans
->list
, &fs_info
->trans_list
);
252 extent_io_tree_init(&cur_trans
->dirty_pages
,
253 fs_info
->btree_inode
->i_mapping
);
254 fs_info
->generation
++;
255 cur_trans
->transid
= fs_info
->generation
;
256 fs_info
->running_transaction
= cur_trans
;
257 cur_trans
->aborted
= 0;
258 spin_unlock(&fs_info
->trans_lock
);
264 * this does all the record keeping required to make sure that a reference
265 * counted root is properly recorded in a given transaction. This is required
266 * to make sure the old root from before we joined the transaction is deleted
267 * when the transaction commits
269 static int record_root_in_trans(struct btrfs_trans_handle
*trans
,
270 struct btrfs_root
*root
)
272 if (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) &&
273 root
->last_trans
< trans
->transid
) {
274 WARN_ON(root
== root
->fs_info
->extent_root
);
275 WARN_ON(root
->commit_root
!= root
->node
);
278 * see below for IN_TRANS_SETUP usage rules
279 * we have the reloc mutex held now, so there
280 * is only one writer in this function
282 set_bit(BTRFS_ROOT_IN_TRANS_SETUP
, &root
->state
);
284 /* make sure readers find IN_TRANS_SETUP before
285 * they find our root->last_trans update
289 spin_lock(&root
->fs_info
->fs_roots_radix_lock
);
290 if (root
->last_trans
== trans
->transid
) {
291 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
294 radix_tree_tag_set(&root
->fs_info
->fs_roots_radix
,
295 (unsigned long)root
->root_key
.objectid
,
296 BTRFS_ROOT_TRANS_TAG
);
297 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
298 root
->last_trans
= trans
->transid
;
300 /* this is pretty tricky. We don't want to
301 * take the relocation lock in btrfs_record_root_in_trans
302 * unless we're really doing the first setup for this root in
305 * Normally we'd use root->last_trans as a flag to decide
306 * if we want to take the expensive mutex.
308 * But, we have to set root->last_trans before we
309 * init the relocation root, otherwise, we trip over warnings
310 * in ctree.c. The solution used here is to flag ourselves
311 * with root IN_TRANS_SETUP. When this is 1, we're still
312 * fixing up the reloc trees and everyone must wait.
314 * When this is zero, they can trust root->last_trans and fly
315 * through btrfs_record_root_in_trans without having to take the
316 * lock. smp_wmb() makes sure that all the writes above are
317 * done before we pop in the zero below
319 btrfs_init_reloc_root(trans
, root
);
320 smp_mb__before_atomic();
321 clear_bit(BTRFS_ROOT_IN_TRANS_SETUP
, &root
->state
);
327 int btrfs_record_root_in_trans(struct btrfs_trans_handle
*trans
,
328 struct btrfs_root
*root
)
330 if (!test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
))
334 * see record_root_in_trans for comments about IN_TRANS_SETUP usage
338 if (root
->last_trans
== trans
->transid
&&
339 !test_bit(BTRFS_ROOT_IN_TRANS_SETUP
, &root
->state
))
342 mutex_lock(&root
->fs_info
->reloc_mutex
);
343 record_root_in_trans(trans
, root
);
344 mutex_unlock(&root
->fs_info
->reloc_mutex
);
349 static inline int is_transaction_blocked(struct btrfs_transaction
*trans
)
351 return (trans
->state
>= TRANS_STATE_BLOCKED
&&
352 trans
->state
< TRANS_STATE_UNBLOCKED
&&
356 /* wait for commit against the current transaction to become unblocked
357 * when this is done, it is safe to start a new transaction, but the current
358 * transaction might not be fully on disk.
360 static void wait_current_trans(struct btrfs_root
*root
)
362 struct btrfs_transaction
*cur_trans
;
364 spin_lock(&root
->fs_info
->trans_lock
);
365 cur_trans
= root
->fs_info
->running_transaction
;
366 if (cur_trans
&& is_transaction_blocked(cur_trans
)) {
367 atomic_inc(&cur_trans
->use_count
);
368 spin_unlock(&root
->fs_info
->trans_lock
);
370 wait_event(root
->fs_info
->transaction_wait
,
371 cur_trans
->state
>= TRANS_STATE_UNBLOCKED
||
373 btrfs_put_transaction(cur_trans
);
375 spin_unlock(&root
->fs_info
->trans_lock
);
379 static int may_wait_transaction(struct btrfs_root
*root
, int type
)
381 if (root
->fs_info
->log_root_recovering
)
384 if (type
== TRANS_USERSPACE
)
387 if (type
== TRANS_START
&&
388 !atomic_read(&root
->fs_info
->open_ioctl_trans
))
394 static inline bool need_reserve_reloc_root(struct btrfs_root
*root
)
396 if (!root
->fs_info
->reloc_ctl
||
397 !test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) ||
398 root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
||
405 static struct btrfs_trans_handle
*
406 start_transaction(struct btrfs_root
*root
, u64 num_items
, unsigned int type
,
407 enum btrfs_reserve_flush_enum flush
)
409 struct btrfs_trans_handle
*h
;
410 struct btrfs_transaction
*cur_trans
;
412 u64 qgroup_reserved
= 0;
413 bool reloc_reserved
= false;
416 /* Send isn't supposed to start transactions. */
417 ASSERT(current
->journal_info
!= BTRFS_SEND_TRANS_STUB
);
419 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
))
420 return ERR_PTR(-EROFS
);
422 if (current
->journal_info
) {
423 WARN_ON(type
& TRANS_EXTWRITERS
);
424 h
= current
->journal_info
;
426 WARN_ON(h
->use_count
> 2);
427 h
->orig_rsv
= h
->block_rsv
;
433 * Do the reservation before we join the transaction so we can do all
434 * the appropriate flushing if need be.
436 if (num_items
> 0 && root
!= root
->fs_info
->chunk_root
) {
437 if (root
->fs_info
->quota_enabled
&&
438 is_fstree(root
->root_key
.objectid
)) {
439 qgroup_reserved
= num_items
* root
->nodesize
;
440 ret
= btrfs_qgroup_reserve(root
, qgroup_reserved
);
445 num_bytes
= btrfs_calc_trans_metadata_size(root
, num_items
);
447 * Do the reservation for the relocation root creation
449 if (need_reserve_reloc_root(root
)) {
450 num_bytes
+= root
->nodesize
;
451 reloc_reserved
= true;
454 ret
= btrfs_block_rsv_add(root
,
455 &root
->fs_info
->trans_block_rsv
,
461 h
= kmem_cache_alloc(btrfs_trans_handle_cachep
, GFP_NOFS
);
468 * If we are JOIN_NOLOCK we're already committing a transaction and
469 * waiting on this guy, so we don't need to do the sb_start_intwrite
470 * because we're already holding a ref. We need this because we could
471 * have raced in and did an fsync() on a file which can kick a commit
472 * and then we deadlock with somebody doing a freeze.
474 * If we are ATTACH, it means we just want to catch the current
475 * transaction and commit it, so we needn't do sb_start_intwrite().
477 if (type
& __TRANS_FREEZABLE
)
478 sb_start_intwrite(root
->fs_info
->sb
);
480 if (may_wait_transaction(root
, type
))
481 wait_current_trans(root
);
484 ret
= join_transaction(root
, type
);
486 wait_current_trans(root
);
487 if (unlikely(type
== TRANS_ATTACH
))
490 } while (ret
== -EBUSY
);
493 /* We must get the transaction if we are JOIN_NOLOCK. */
494 BUG_ON(type
== TRANS_JOIN_NOLOCK
);
498 cur_trans
= root
->fs_info
->running_transaction
;
500 h
->transid
= cur_trans
->transid
;
501 h
->transaction
= cur_trans
;
503 h
->bytes_reserved
= 0;
505 h
->delayed_ref_updates
= 0;
511 h
->qgroup_reserved
= 0;
512 h
->delayed_ref_elem
.seq
= 0;
514 h
->allocating_chunk
= false;
515 h
->reloc_reserved
= false;
517 INIT_LIST_HEAD(&h
->qgroup_ref_list
);
518 INIT_LIST_HEAD(&h
->new_bgs
);
519 INIT_LIST_HEAD(&h
->ordered
);
522 if (cur_trans
->state
>= TRANS_STATE_BLOCKED
&&
523 may_wait_transaction(root
, type
)) {
524 current
->journal_info
= h
;
525 btrfs_commit_transaction(h
, root
);
530 trace_btrfs_space_reservation(root
->fs_info
, "transaction",
531 h
->transid
, num_bytes
, 1);
532 h
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
533 h
->bytes_reserved
= num_bytes
;
534 h
->reloc_reserved
= reloc_reserved
;
536 h
->qgroup_reserved
= qgroup_reserved
;
539 btrfs_record_root_in_trans(h
, root
);
541 if (!current
->journal_info
&& type
!= TRANS_USERSPACE
)
542 current
->journal_info
= h
;
546 if (type
& __TRANS_FREEZABLE
)
547 sb_end_intwrite(root
->fs_info
->sb
);
548 kmem_cache_free(btrfs_trans_handle_cachep
, h
);
551 btrfs_block_rsv_release(root
, &root
->fs_info
->trans_block_rsv
,
555 btrfs_qgroup_free(root
, qgroup_reserved
);
559 struct btrfs_trans_handle
*btrfs_start_transaction(struct btrfs_root
*root
,
562 return start_transaction(root
, num_items
, TRANS_START
,
563 BTRFS_RESERVE_FLUSH_ALL
);
566 struct btrfs_trans_handle
*btrfs_start_transaction_lflush(
567 struct btrfs_root
*root
, int num_items
)
569 return start_transaction(root
, num_items
, TRANS_START
,
570 BTRFS_RESERVE_FLUSH_LIMIT
);
573 struct btrfs_trans_handle
*btrfs_join_transaction(struct btrfs_root
*root
)
575 return start_transaction(root
, 0, TRANS_JOIN
, 0);
578 struct btrfs_trans_handle
*btrfs_join_transaction_nolock(struct btrfs_root
*root
)
580 return start_transaction(root
, 0, TRANS_JOIN_NOLOCK
, 0);
583 struct btrfs_trans_handle
*btrfs_start_ioctl_transaction(struct btrfs_root
*root
)
585 return start_transaction(root
, 0, TRANS_USERSPACE
, 0);
589 * btrfs_attach_transaction() - catch the running transaction
591 * It is used when we want to commit the current the transaction, but
592 * don't want to start a new one.
594 * Note: If this function return -ENOENT, it just means there is no
595 * running transaction. But it is possible that the inactive transaction
596 * is still in the memory, not fully on disk. If you hope there is no
597 * inactive transaction in the fs when -ENOENT is returned, you should
599 * btrfs_attach_transaction_barrier()
601 struct btrfs_trans_handle
*btrfs_attach_transaction(struct btrfs_root
*root
)
603 return start_transaction(root
, 0, TRANS_ATTACH
, 0);
607 * btrfs_attach_transaction_barrier() - catch the running transaction
609 * It is similar to the above function, the differentia is this one
610 * will wait for all the inactive transactions until they fully
613 struct btrfs_trans_handle
*
614 btrfs_attach_transaction_barrier(struct btrfs_root
*root
)
616 struct btrfs_trans_handle
*trans
;
618 trans
= start_transaction(root
, 0, TRANS_ATTACH
, 0);
619 if (IS_ERR(trans
) && PTR_ERR(trans
) == -ENOENT
)
620 btrfs_wait_for_commit(root
, 0);
625 /* wait for a transaction commit to be fully complete */
626 static noinline
void wait_for_commit(struct btrfs_root
*root
,
627 struct btrfs_transaction
*commit
)
629 wait_event(commit
->commit_wait
, commit
->state
== TRANS_STATE_COMPLETED
);
632 int btrfs_wait_for_commit(struct btrfs_root
*root
, u64 transid
)
634 struct btrfs_transaction
*cur_trans
= NULL
, *t
;
638 if (transid
<= root
->fs_info
->last_trans_committed
)
641 /* find specified transaction */
642 spin_lock(&root
->fs_info
->trans_lock
);
643 list_for_each_entry(t
, &root
->fs_info
->trans_list
, list
) {
644 if (t
->transid
== transid
) {
646 atomic_inc(&cur_trans
->use_count
);
650 if (t
->transid
> transid
) {
655 spin_unlock(&root
->fs_info
->trans_lock
);
658 * The specified transaction doesn't exist, or we
659 * raced with btrfs_commit_transaction
662 if (transid
> root
->fs_info
->last_trans_committed
)
667 /* find newest transaction that is committing | committed */
668 spin_lock(&root
->fs_info
->trans_lock
);
669 list_for_each_entry_reverse(t
, &root
->fs_info
->trans_list
,
671 if (t
->state
>= TRANS_STATE_COMMIT_START
) {
672 if (t
->state
== TRANS_STATE_COMPLETED
)
675 atomic_inc(&cur_trans
->use_count
);
679 spin_unlock(&root
->fs_info
->trans_lock
);
681 goto out
; /* nothing committing|committed */
684 wait_for_commit(root
, cur_trans
);
685 btrfs_put_transaction(cur_trans
);
690 void btrfs_throttle(struct btrfs_root
*root
)
692 if (!atomic_read(&root
->fs_info
->open_ioctl_trans
))
693 wait_current_trans(root
);
696 static int should_end_transaction(struct btrfs_trans_handle
*trans
,
697 struct btrfs_root
*root
)
699 if (root
->fs_info
->global_block_rsv
.space_info
->full
&&
700 btrfs_check_space_for_delayed_refs(trans
, root
))
703 return !!btrfs_block_rsv_check(root
, &root
->fs_info
->global_block_rsv
, 5);
706 int btrfs_should_end_transaction(struct btrfs_trans_handle
*trans
,
707 struct btrfs_root
*root
)
709 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
714 if (cur_trans
->state
>= TRANS_STATE_BLOCKED
||
715 cur_trans
->delayed_refs
.flushing
)
718 updates
= trans
->delayed_ref_updates
;
719 trans
->delayed_ref_updates
= 0;
721 err
= btrfs_run_delayed_refs(trans
, root
, updates
);
722 if (err
) /* Error code will also eval true */
726 return should_end_transaction(trans
, root
);
729 static int __btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
730 struct btrfs_root
*root
, int throttle
)
732 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
733 struct btrfs_fs_info
*info
= root
->fs_info
;
734 unsigned long cur
= trans
->delayed_ref_updates
;
735 int lock
= (trans
->type
!= TRANS_JOIN_NOLOCK
);
737 int must_run_delayed_refs
= 0;
739 if (trans
->use_count
> 1) {
741 trans
->block_rsv
= trans
->orig_rsv
;
745 btrfs_trans_release_metadata(trans
, root
);
746 trans
->block_rsv
= NULL
;
748 if (!list_empty(&trans
->new_bgs
))
749 btrfs_create_pending_block_groups(trans
, root
);
751 if (!list_empty(&trans
->ordered
)) {
752 spin_lock(&info
->trans_lock
);
753 list_splice(&trans
->ordered
, &cur_trans
->pending_ordered
);
754 spin_unlock(&info
->trans_lock
);
757 trans
->delayed_ref_updates
= 0;
759 must_run_delayed_refs
=
760 btrfs_should_throttle_delayed_refs(trans
, root
);
761 cur
= max_t(unsigned long, cur
, 32);
764 * don't make the caller wait if they are from a NOLOCK
765 * or ATTACH transaction, it will deadlock with commit
767 if (must_run_delayed_refs
== 1 &&
768 (trans
->type
& (__TRANS_JOIN_NOLOCK
| __TRANS_ATTACH
)))
769 must_run_delayed_refs
= 2;
772 if (trans
->qgroup_reserved
) {
774 * the same root has to be passed here between start_transaction
775 * and end_transaction. Subvolume quota depends on this.
777 btrfs_qgroup_free(trans
->root
, trans
->qgroup_reserved
);
778 trans
->qgroup_reserved
= 0;
781 btrfs_trans_release_metadata(trans
, root
);
782 trans
->block_rsv
= NULL
;
784 if (!list_empty(&trans
->new_bgs
))
785 btrfs_create_pending_block_groups(trans
, root
);
787 if (lock
&& !atomic_read(&root
->fs_info
->open_ioctl_trans
) &&
788 should_end_transaction(trans
, root
) &&
789 ACCESS_ONCE(cur_trans
->state
) == TRANS_STATE_RUNNING
) {
790 spin_lock(&info
->trans_lock
);
791 if (cur_trans
->state
== TRANS_STATE_RUNNING
)
792 cur_trans
->state
= TRANS_STATE_BLOCKED
;
793 spin_unlock(&info
->trans_lock
);
796 if (lock
&& ACCESS_ONCE(cur_trans
->state
) == TRANS_STATE_BLOCKED
) {
798 return btrfs_commit_transaction(trans
, root
);
800 wake_up_process(info
->transaction_kthread
);
803 if (trans
->type
& __TRANS_FREEZABLE
)
804 sb_end_intwrite(root
->fs_info
->sb
);
806 WARN_ON(cur_trans
!= info
->running_transaction
);
807 WARN_ON(atomic_read(&cur_trans
->num_writers
) < 1);
808 atomic_dec(&cur_trans
->num_writers
);
809 extwriter_counter_dec(cur_trans
, trans
->type
);
812 if (waitqueue_active(&cur_trans
->writer_wait
))
813 wake_up(&cur_trans
->writer_wait
);
814 btrfs_put_transaction(cur_trans
);
816 if (current
->journal_info
== trans
)
817 current
->journal_info
= NULL
;
820 btrfs_run_delayed_iputs(root
);
822 if (trans
->aborted
||
823 test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
)) {
824 wake_up_process(info
->transaction_kthread
);
827 assert_qgroups_uptodate(trans
);
829 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
830 if (must_run_delayed_refs
) {
831 btrfs_async_run_delayed_refs(root
, cur
,
832 must_run_delayed_refs
== 1);
837 int btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
838 struct btrfs_root
*root
)
840 return __btrfs_end_transaction(trans
, root
, 0);
843 int btrfs_end_transaction_throttle(struct btrfs_trans_handle
*trans
,
844 struct btrfs_root
*root
)
846 return __btrfs_end_transaction(trans
, root
, 1);
850 * when btree blocks are allocated, they have some corresponding bits set for
851 * them in one of two extent_io trees. This is used to make sure all of
852 * those extents are sent to disk but does not wait on them
854 int btrfs_write_marked_extents(struct btrfs_root
*root
,
855 struct extent_io_tree
*dirty_pages
, int mark
)
859 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
860 struct extent_state
*cached_state
= NULL
;
864 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
865 mark
, &cached_state
)) {
866 bool wait_writeback
= false;
868 err
= convert_extent_bit(dirty_pages
, start
, end
,
870 mark
, &cached_state
, GFP_NOFS
);
872 * convert_extent_bit can return -ENOMEM, which is most of the
873 * time a temporary error. So when it happens, ignore the error
874 * and wait for writeback of this range to finish - because we
875 * failed to set the bit EXTENT_NEED_WAIT for the range, a call
876 * to btrfs_wait_marked_extents() would not know that writeback
877 * for this range started and therefore wouldn't wait for it to
878 * finish - we don't want to commit a superblock that points to
879 * btree nodes/leafs for which writeback hasn't finished yet
880 * (and without errors).
881 * We cleanup any entries left in the io tree when committing
882 * the transaction (through clear_btree_io_tree()).
884 if (err
== -ENOMEM
) {
886 wait_writeback
= true;
889 err
= filemap_fdatawrite_range(mapping
, start
, end
);
892 else if (wait_writeback
)
893 werr
= filemap_fdatawait_range(mapping
, start
, end
);
894 free_extent_state(cached_state
);
903 * when btree blocks are allocated, they have some corresponding bits set for
904 * them in one of two extent_io trees. This is used to make sure all of
905 * those extents are on disk for transaction or log commit. We wait
906 * on all the pages and clear them from the dirty pages state tree
908 int btrfs_wait_marked_extents(struct btrfs_root
*root
,
909 struct extent_io_tree
*dirty_pages
, int mark
)
913 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
914 struct extent_state
*cached_state
= NULL
;
917 struct btrfs_inode
*btree_ino
= BTRFS_I(root
->fs_info
->btree_inode
);
920 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
921 EXTENT_NEED_WAIT
, &cached_state
)) {
923 * Ignore -ENOMEM errors returned by clear_extent_bit().
924 * When committing the transaction, we'll remove any entries
925 * left in the io tree. For a log commit, we don't remove them
926 * after committing the log because the tree can be accessed
927 * concurrently - we do it only at transaction commit time when
928 * it's safe to do it (through clear_btree_io_tree()).
930 err
= clear_extent_bit(dirty_pages
, start
, end
,
932 0, 0, &cached_state
, GFP_NOFS
);
936 err
= filemap_fdatawait_range(mapping
, start
, end
);
939 free_extent_state(cached_state
);
947 if (root
->root_key
.objectid
== BTRFS_TREE_LOG_OBJECTID
) {
948 if ((mark
& EXTENT_DIRTY
) &&
949 test_and_clear_bit(BTRFS_INODE_BTREE_LOG1_ERR
,
950 &btree_ino
->runtime_flags
))
953 if ((mark
& EXTENT_NEW
) &&
954 test_and_clear_bit(BTRFS_INODE_BTREE_LOG2_ERR
,
955 &btree_ino
->runtime_flags
))
958 if (test_and_clear_bit(BTRFS_INODE_BTREE_ERR
,
959 &btree_ino
->runtime_flags
))
970 * when btree blocks are allocated, they have some corresponding bits set for
971 * them in one of two extent_io trees. This is used to make sure all of
972 * those extents are on disk for transaction or log commit
974 static int btrfs_write_and_wait_marked_extents(struct btrfs_root
*root
,
975 struct extent_io_tree
*dirty_pages
, int mark
)
979 struct blk_plug plug
;
981 blk_start_plug(&plug
);
982 ret
= btrfs_write_marked_extents(root
, dirty_pages
, mark
);
983 blk_finish_plug(&plug
);
984 ret2
= btrfs_wait_marked_extents(root
, dirty_pages
, mark
);
993 static int btrfs_write_and_wait_transaction(struct btrfs_trans_handle
*trans
,
994 struct btrfs_root
*root
)
998 ret
= btrfs_write_and_wait_marked_extents(root
,
999 &trans
->transaction
->dirty_pages
,
1001 clear_btree_io_tree(&trans
->transaction
->dirty_pages
);
1007 * this is used to update the root pointer in the tree of tree roots.
1009 * But, in the case of the extent allocation tree, updating the root
1010 * pointer may allocate blocks which may change the root of the extent
1013 * So, this loops and repeats and makes sure the cowonly root didn't
1014 * change while the root pointer was being updated in the metadata.
1016 static int update_cowonly_root(struct btrfs_trans_handle
*trans
,
1017 struct btrfs_root
*root
)
1020 u64 old_root_bytenr
;
1022 struct btrfs_root
*tree_root
= root
->fs_info
->tree_root
;
1024 old_root_used
= btrfs_root_used(&root
->root_item
);
1025 btrfs_write_dirty_block_groups(trans
, root
);
1028 old_root_bytenr
= btrfs_root_bytenr(&root
->root_item
);
1029 if (old_root_bytenr
== root
->node
->start
&&
1030 old_root_used
== btrfs_root_used(&root
->root_item
))
1033 btrfs_set_root_node(&root
->root_item
, root
->node
);
1034 ret
= btrfs_update_root(trans
, tree_root
,
1040 old_root_used
= btrfs_root_used(&root
->root_item
);
1041 ret
= btrfs_write_dirty_block_groups(trans
, root
);
1050 * update all the cowonly tree roots on disk
1052 * The error handling in this function may not be obvious. Any of the
1053 * failures will cause the file system to go offline. We still need
1054 * to clean up the delayed refs.
1056 static noinline
int commit_cowonly_roots(struct btrfs_trans_handle
*trans
,
1057 struct btrfs_root
*root
)
1059 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1060 struct list_head
*next
;
1061 struct extent_buffer
*eb
;
1064 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1068 eb
= btrfs_lock_root_node(fs_info
->tree_root
);
1069 ret
= btrfs_cow_block(trans
, fs_info
->tree_root
, eb
, NULL
,
1071 btrfs_tree_unlock(eb
);
1072 free_extent_buffer(eb
);
1077 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1081 ret
= btrfs_run_dev_stats(trans
, root
->fs_info
);
1084 ret
= btrfs_run_dev_replace(trans
, root
->fs_info
);
1087 ret
= btrfs_run_qgroups(trans
, root
->fs_info
);
1091 /* run_qgroups might have added some more refs */
1092 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1096 while (!list_empty(&fs_info
->dirty_cowonly_roots
)) {
1097 next
= fs_info
->dirty_cowonly_roots
.next
;
1098 list_del_init(next
);
1099 root
= list_entry(next
, struct btrfs_root
, dirty_list
);
1101 if (root
!= fs_info
->extent_root
)
1102 list_add_tail(&root
->dirty_list
,
1103 &trans
->transaction
->switch_commits
);
1104 ret
= update_cowonly_root(trans
, root
);
1109 list_add_tail(&fs_info
->extent_root
->dirty_list
,
1110 &trans
->transaction
->switch_commits
);
1111 btrfs_after_dev_replace_commit(fs_info
);
1117 * dead roots are old snapshots that need to be deleted. This allocates
1118 * a dirty root struct and adds it into the list of dead roots that need to
1121 void btrfs_add_dead_root(struct btrfs_root
*root
)
1123 spin_lock(&root
->fs_info
->trans_lock
);
1124 if (list_empty(&root
->root_list
))
1125 list_add_tail(&root
->root_list
, &root
->fs_info
->dead_roots
);
1126 spin_unlock(&root
->fs_info
->trans_lock
);
1130 * update all the cowonly tree roots on disk
1132 static noinline
int commit_fs_roots(struct btrfs_trans_handle
*trans
,
1133 struct btrfs_root
*root
)
1135 struct btrfs_root
*gang
[8];
1136 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1141 spin_lock(&fs_info
->fs_roots_radix_lock
);
1143 ret
= radix_tree_gang_lookup_tag(&fs_info
->fs_roots_radix
,
1146 BTRFS_ROOT_TRANS_TAG
);
1149 for (i
= 0; i
< ret
; i
++) {
1151 radix_tree_tag_clear(&fs_info
->fs_roots_radix
,
1152 (unsigned long)root
->root_key
.objectid
,
1153 BTRFS_ROOT_TRANS_TAG
);
1154 spin_unlock(&fs_info
->fs_roots_radix_lock
);
1156 btrfs_free_log(trans
, root
);
1157 btrfs_update_reloc_root(trans
, root
);
1158 btrfs_orphan_commit_root(trans
, root
);
1160 btrfs_save_ino_cache(root
, trans
);
1162 /* see comments in should_cow_block() */
1163 clear_bit(BTRFS_ROOT_FORCE_COW
, &root
->state
);
1164 smp_mb__after_atomic();
1166 if (root
->commit_root
!= root
->node
) {
1167 list_add_tail(&root
->dirty_list
,
1168 &trans
->transaction
->switch_commits
);
1169 btrfs_set_root_node(&root
->root_item
,
1173 err
= btrfs_update_root(trans
, fs_info
->tree_root
,
1176 spin_lock(&fs_info
->fs_roots_radix_lock
);
1181 spin_unlock(&fs_info
->fs_roots_radix_lock
);
1186 * defrag a given btree.
1187 * Every leaf in the btree is read and defragged.
1189 int btrfs_defrag_root(struct btrfs_root
*root
)
1191 struct btrfs_fs_info
*info
= root
->fs_info
;
1192 struct btrfs_trans_handle
*trans
;
1195 if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING
, &root
->state
))
1199 trans
= btrfs_start_transaction(root
, 0);
1201 return PTR_ERR(trans
);
1203 ret
= btrfs_defrag_leaves(trans
, root
);
1205 btrfs_end_transaction(trans
, root
);
1206 btrfs_btree_balance_dirty(info
->tree_root
);
1209 if (btrfs_fs_closing(root
->fs_info
) || ret
!= -EAGAIN
)
1212 if (btrfs_defrag_cancelled(root
->fs_info
)) {
1213 pr_debug("BTRFS: defrag_root cancelled\n");
1218 clear_bit(BTRFS_ROOT_DEFRAG_RUNNING
, &root
->state
);
1223 * new snapshots need to be created at a very specific time in the
1224 * transaction commit. This does the actual creation.
1227 * If the error which may affect the commitment of the current transaction
1228 * happens, we should return the error number. If the error which just affect
1229 * the creation of the pending snapshots, just return 0.
1231 static noinline
int create_pending_snapshot(struct btrfs_trans_handle
*trans
,
1232 struct btrfs_fs_info
*fs_info
,
1233 struct btrfs_pending_snapshot
*pending
)
1235 struct btrfs_key key
;
1236 struct btrfs_root_item
*new_root_item
;
1237 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
1238 struct btrfs_root
*root
= pending
->root
;
1239 struct btrfs_root
*parent_root
;
1240 struct btrfs_block_rsv
*rsv
;
1241 struct inode
*parent_inode
;
1242 struct btrfs_path
*path
;
1243 struct btrfs_dir_item
*dir_item
;
1244 struct dentry
*dentry
;
1245 struct extent_buffer
*tmp
;
1246 struct extent_buffer
*old
;
1247 struct timespec cur_time
= CURRENT_TIME
;
1255 path
= btrfs_alloc_path();
1257 pending
->error
= -ENOMEM
;
1261 new_root_item
= kmalloc(sizeof(*new_root_item
), GFP_NOFS
);
1262 if (!new_root_item
) {
1263 pending
->error
= -ENOMEM
;
1264 goto root_item_alloc_fail
;
1267 pending
->error
= btrfs_find_free_objectid(tree_root
, &objectid
);
1269 goto no_free_objectid
;
1271 btrfs_reloc_pre_snapshot(trans
, pending
, &to_reserve
);
1273 if (to_reserve
> 0) {
1274 pending
->error
= btrfs_block_rsv_add(root
,
1275 &pending
->block_rsv
,
1277 BTRFS_RESERVE_NO_FLUSH
);
1279 goto no_free_objectid
;
1282 key
.objectid
= objectid
;
1283 key
.offset
= (u64
)-1;
1284 key
.type
= BTRFS_ROOT_ITEM_KEY
;
1286 rsv
= trans
->block_rsv
;
1287 trans
->block_rsv
= &pending
->block_rsv
;
1288 trans
->bytes_reserved
= trans
->block_rsv
->reserved
;
1290 dentry
= pending
->dentry
;
1291 parent_inode
= pending
->dir
;
1292 parent_root
= BTRFS_I(parent_inode
)->root
;
1293 record_root_in_trans(trans
, parent_root
);
1296 * insert the directory item
1298 ret
= btrfs_set_inode_index(parent_inode
, &index
);
1299 BUG_ON(ret
); /* -ENOMEM */
1301 /* check if there is a file/dir which has the same name. */
1302 dir_item
= btrfs_lookup_dir_item(NULL
, parent_root
, path
,
1303 btrfs_ino(parent_inode
),
1304 dentry
->d_name
.name
,
1305 dentry
->d_name
.len
, 0);
1306 if (dir_item
!= NULL
&& !IS_ERR(dir_item
)) {
1307 pending
->error
= -EEXIST
;
1308 goto dir_item_existed
;
1309 } else if (IS_ERR(dir_item
)) {
1310 ret
= PTR_ERR(dir_item
);
1311 btrfs_abort_transaction(trans
, root
, ret
);
1314 btrfs_release_path(path
);
1317 * pull in the delayed directory update
1318 * and the delayed inode item
1319 * otherwise we corrupt the FS during
1322 ret
= btrfs_run_delayed_items(trans
, root
);
1323 if (ret
) { /* Transaction aborted */
1324 btrfs_abort_transaction(trans
, root
, ret
);
1328 record_root_in_trans(trans
, root
);
1329 btrfs_set_root_last_snapshot(&root
->root_item
, trans
->transid
);
1330 memcpy(new_root_item
, &root
->root_item
, sizeof(*new_root_item
));
1331 btrfs_check_and_init_root_item(new_root_item
);
1333 root_flags
= btrfs_root_flags(new_root_item
);
1334 if (pending
->readonly
)
1335 root_flags
|= BTRFS_ROOT_SUBVOL_RDONLY
;
1337 root_flags
&= ~BTRFS_ROOT_SUBVOL_RDONLY
;
1338 btrfs_set_root_flags(new_root_item
, root_flags
);
1340 btrfs_set_root_generation_v2(new_root_item
,
1342 uuid_le_gen(&new_uuid
);
1343 memcpy(new_root_item
->uuid
, new_uuid
.b
, BTRFS_UUID_SIZE
);
1344 memcpy(new_root_item
->parent_uuid
, root
->root_item
.uuid
,
1346 if (!(root_flags
& BTRFS_ROOT_SUBVOL_RDONLY
)) {
1347 memset(new_root_item
->received_uuid
, 0,
1348 sizeof(new_root_item
->received_uuid
));
1349 memset(&new_root_item
->stime
, 0, sizeof(new_root_item
->stime
));
1350 memset(&new_root_item
->rtime
, 0, sizeof(new_root_item
->rtime
));
1351 btrfs_set_root_stransid(new_root_item
, 0);
1352 btrfs_set_root_rtransid(new_root_item
, 0);
1354 btrfs_set_stack_timespec_sec(&new_root_item
->otime
, cur_time
.tv_sec
);
1355 btrfs_set_stack_timespec_nsec(&new_root_item
->otime
, cur_time
.tv_nsec
);
1356 btrfs_set_root_otransid(new_root_item
, trans
->transid
);
1358 old
= btrfs_lock_root_node(root
);
1359 ret
= btrfs_cow_block(trans
, root
, old
, NULL
, 0, &old
);
1361 btrfs_tree_unlock(old
);
1362 free_extent_buffer(old
);
1363 btrfs_abort_transaction(trans
, root
, ret
);
1367 btrfs_set_lock_blocking(old
);
1369 ret
= btrfs_copy_root(trans
, root
, old
, &tmp
, objectid
);
1370 /* clean up in any case */
1371 btrfs_tree_unlock(old
);
1372 free_extent_buffer(old
);
1374 btrfs_abort_transaction(trans
, root
, ret
);
1379 * We need to flush delayed refs in order to make sure all of our quota
1380 * operations have been done before we call btrfs_qgroup_inherit.
1382 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1384 btrfs_abort_transaction(trans
, root
, ret
);
1388 ret
= btrfs_qgroup_inherit(trans
, fs_info
,
1389 root
->root_key
.objectid
,
1390 objectid
, pending
->inherit
);
1392 btrfs_abort_transaction(trans
, root
, ret
);
1396 /* see comments in should_cow_block() */
1397 set_bit(BTRFS_ROOT_FORCE_COW
, &root
->state
);
1400 btrfs_set_root_node(new_root_item
, tmp
);
1401 /* record when the snapshot was created in key.offset */
1402 key
.offset
= trans
->transid
;
1403 ret
= btrfs_insert_root(trans
, tree_root
, &key
, new_root_item
);
1404 btrfs_tree_unlock(tmp
);
1405 free_extent_buffer(tmp
);
1407 btrfs_abort_transaction(trans
, root
, ret
);
1412 * insert root back/forward references
1414 ret
= btrfs_add_root_ref(trans
, tree_root
, objectid
,
1415 parent_root
->root_key
.objectid
,
1416 btrfs_ino(parent_inode
), index
,
1417 dentry
->d_name
.name
, dentry
->d_name
.len
);
1419 btrfs_abort_transaction(trans
, root
, ret
);
1423 key
.offset
= (u64
)-1;
1424 pending
->snap
= btrfs_read_fs_root_no_name(root
->fs_info
, &key
);
1425 if (IS_ERR(pending
->snap
)) {
1426 ret
= PTR_ERR(pending
->snap
);
1427 btrfs_abort_transaction(trans
, root
, ret
);
1431 ret
= btrfs_reloc_post_snapshot(trans
, pending
);
1433 btrfs_abort_transaction(trans
, root
, ret
);
1437 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1439 btrfs_abort_transaction(trans
, root
, ret
);
1443 ret
= btrfs_insert_dir_item(trans
, parent_root
,
1444 dentry
->d_name
.name
, dentry
->d_name
.len
,
1446 BTRFS_FT_DIR
, index
);
1447 /* We have check then name at the beginning, so it is impossible. */
1448 BUG_ON(ret
== -EEXIST
|| ret
== -EOVERFLOW
);
1450 btrfs_abort_transaction(trans
, root
, ret
);
1454 btrfs_i_size_write(parent_inode
, parent_inode
->i_size
+
1455 dentry
->d_name
.len
* 2);
1456 parent_inode
->i_mtime
= parent_inode
->i_ctime
= CURRENT_TIME
;
1457 ret
= btrfs_update_inode_fallback(trans
, parent_root
, parent_inode
);
1459 btrfs_abort_transaction(trans
, root
, ret
);
1462 ret
= btrfs_uuid_tree_add(trans
, fs_info
->uuid_root
, new_uuid
.b
,
1463 BTRFS_UUID_KEY_SUBVOL
, objectid
);
1465 btrfs_abort_transaction(trans
, root
, ret
);
1468 if (!btrfs_is_empty_uuid(new_root_item
->received_uuid
)) {
1469 ret
= btrfs_uuid_tree_add(trans
, fs_info
->uuid_root
,
1470 new_root_item
->received_uuid
,
1471 BTRFS_UUID_KEY_RECEIVED_SUBVOL
,
1473 if (ret
&& ret
!= -EEXIST
) {
1474 btrfs_abort_transaction(trans
, root
, ret
);
1479 pending
->error
= ret
;
1481 trans
->block_rsv
= rsv
;
1482 trans
->bytes_reserved
= 0;
1484 kfree(new_root_item
);
1485 root_item_alloc_fail
:
1486 btrfs_free_path(path
);
1491 * create all the snapshots we've scheduled for creation
1493 static noinline
int create_pending_snapshots(struct btrfs_trans_handle
*trans
,
1494 struct btrfs_fs_info
*fs_info
)
1496 struct btrfs_pending_snapshot
*pending
, *next
;
1497 struct list_head
*head
= &trans
->transaction
->pending_snapshots
;
1500 list_for_each_entry_safe(pending
, next
, head
, list
) {
1501 list_del(&pending
->list
);
1502 ret
= create_pending_snapshot(trans
, fs_info
, pending
);
1509 static void update_super_roots(struct btrfs_root
*root
)
1511 struct btrfs_root_item
*root_item
;
1512 struct btrfs_super_block
*super
;
1514 super
= root
->fs_info
->super_copy
;
1516 root_item
= &root
->fs_info
->chunk_root
->root_item
;
1517 super
->chunk_root
= root_item
->bytenr
;
1518 super
->chunk_root_generation
= root_item
->generation
;
1519 super
->chunk_root_level
= root_item
->level
;
1521 root_item
= &root
->fs_info
->tree_root
->root_item
;
1522 super
->root
= root_item
->bytenr
;
1523 super
->generation
= root_item
->generation
;
1524 super
->root_level
= root_item
->level
;
1525 if (btrfs_test_opt(root
, SPACE_CACHE
))
1526 super
->cache_generation
= root_item
->generation
;
1527 if (root
->fs_info
->update_uuid_tree_gen
)
1528 super
->uuid_tree_generation
= root_item
->generation
;
1531 int btrfs_transaction_in_commit(struct btrfs_fs_info
*info
)
1533 struct btrfs_transaction
*trans
;
1536 spin_lock(&info
->trans_lock
);
1537 trans
= info
->running_transaction
;
1539 ret
= (trans
->state
>= TRANS_STATE_COMMIT_START
);
1540 spin_unlock(&info
->trans_lock
);
1544 int btrfs_transaction_blocked(struct btrfs_fs_info
*info
)
1546 struct btrfs_transaction
*trans
;
1549 spin_lock(&info
->trans_lock
);
1550 trans
= info
->running_transaction
;
1552 ret
= is_transaction_blocked(trans
);
1553 spin_unlock(&info
->trans_lock
);
1558 * wait for the current transaction commit to start and block subsequent
1561 static void wait_current_trans_commit_start(struct btrfs_root
*root
,
1562 struct btrfs_transaction
*trans
)
1564 wait_event(root
->fs_info
->transaction_blocked_wait
,
1565 trans
->state
>= TRANS_STATE_COMMIT_START
||
1570 * wait for the current transaction to start and then become unblocked.
1573 static void wait_current_trans_commit_start_and_unblock(struct btrfs_root
*root
,
1574 struct btrfs_transaction
*trans
)
1576 wait_event(root
->fs_info
->transaction_wait
,
1577 trans
->state
>= TRANS_STATE_UNBLOCKED
||
1582 * commit transactions asynchronously. once btrfs_commit_transaction_async
1583 * returns, any subsequent transaction will not be allowed to join.
1585 struct btrfs_async_commit
{
1586 struct btrfs_trans_handle
*newtrans
;
1587 struct btrfs_root
*root
;
1588 struct work_struct work
;
1591 static void do_async_commit(struct work_struct
*work
)
1593 struct btrfs_async_commit
*ac
=
1594 container_of(work
, struct btrfs_async_commit
, work
);
1597 * We've got freeze protection passed with the transaction.
1598 * Tell lockdep about it.
1600 if (ac
->newtrans
->type
& __TRANS_FREEZABLE
)
1602 &ac
->root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1605 current
->journal_info
= ac
->newtrans
;
1607 btrfs_commit_transaction(ac
->newtrans
, ac
->root
);
1611 int btrfs_commit_transaction_async(struct btrfs_trans_handle
*trans
,
1612 struct btrfs_root
*root
,
1613 int wait_for_unblock
)
1615 struct btrfs_async_commit
*ac
;
1616 struct btrfs_transaction
*cur_trans
;
1618 ac
= kmalloc(sizeof(*ac
), GFP_NOFS
);
1622 INIT_WORK(&ac
->work
, do_async_commit
);
1624 ac
->newtrans
= btrfs_join_transaction(root
);
1625 if (IS_ERR(ac
->newtrans
)) {
1626 int err
= PTR_ERR(ac
->newtrans
);
1631 /* take transaction reference */
1632 cur_trans
= trans
->transaction
;
1633 atomic_inc(&cur_trans
->use_count
);
1635 btrfs_end_transaction(trans
, root
);
1638 * Tell lockdep we've released the freeze rwsem, since the
1639 * async commit thread will be the one to unlock it.
1641 if (ac
->newtrans
->type
& __TRANS_FREEZABLE
)
1643 &root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1646 schedule_work(&ac
->work
);
1648 /* wait for transaction to start and unblock */
1649 if (wait_for_unblock
)
1650 wait_current_trans_commit_start_and_unblock(root
, cur_trans
);
1652 wait_current_trans_commit_start(root
, cur_trans
);
1654 if (current
->journal_info
== trans
)
1655 current
->journal_info
= NULL
;
1657 btrfs_put_transaction(cur_trans
);
1662 static void cleanup_transaction(struct btrfs_trans_handle
*trans
,
1663 struct btrfs_root
*root
, int err
)
1665 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1668 WARN_ON(trans
->use_count
> 1);
1670 btrfs_abort_transaction(trans
, root
, err
);
1672 spin_lock(&root
->fs_info
->trans_lock
);
1675 * If the transaction is removed from the list, it means this
1676 * transaction has been committed successfully, so it is impossible
1677 * to call the cleanup function.
1679 BUG_ON(list_empty(&cur_trans
->list
));
1681 list_del_init(&cur_trans
->list
);
1682 if (cur_trans
== root
->fs_info
->running_transaction
) {
1683 cur_trans
->state
= TRANS_STATE_COMMIT_DOING
;
1684 spin_unlock(&root
->fs_info
->trans_lock
);
1685 wait_event(cur_trans
->writer_wait
,
1686 atomic_read(&cur_trans
->num_writers
) == 1);
1688 spin_lock(&root
->fs_info
->trans_lock
);
1690 spin_unlock(&root
->fs_info
->trans_lock
);
1692 btrfs_cleanup_one_transaction(trans
->transaction
, root
);
1694 spin_lock(&root
->fs_info
->trans_lock
);
1695 if (cur_trans
== root
->fs_info
->running_transaction
)
1696 root
->fs_info
->running_transaction
= NULL
;
1697 spin_unlock(&root
->fs_info
->trans_lock
);
1699 if (trans
->type
& __TRANS_FREEZABLE
)
1700 sb_end_intwrite(root
->fs_info
->sb
);
1701 btrfs_put_transaction(cur_trans
);
1702 btrfs_put_transaction(cur_trans
);
1704 trace_btrfs_transaction_commit(root
);
1706 if (current
->journal_info
== trans
)
1707 current
->journal_info
= NULL
;
1708 btrfs_scrub_cancel(root
->fs_info
);
1710 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
1713 static inline int btrfs_start_delalloc_flush(struct btrfs_fs_info
*fs_info
)
1715 if (btrfs_test_opt(fs_info
->tree_root
, FLUSHONCOMMIT
))
1716 return btrfs_start_delalloc_roots(fs_info
, 1, -1);
1720 static inline void btrfs_wait_delalloc_flush(struct btrfs_fs_info
*fs_info
)
1722 if (btrfs_test_opt(fs_info
->tree_root
, FLUSHONCOMMIT
))
1723 btrfs_wait_ordered_roots(fs_info
, -1);
1727 btrfs_wait_pending_ordered(struct btrfs_transaction
*cur_trans
,
1728 struct btrfs_fs_info
*fs_info
)
1730 struct btrfs_ordered_extent
*ordered
;
1732 spin_lock(&fs_info
->trans_lock
);
1733 while (!list_empty(&cur_trans
->pending_ordered
)) {
1734 ordered
= list_first_entry(&cur_trans
->pending_ordered
,
1735 struct btrfs_ordered_extent
,
1737 list_del_init(&ordered
->trans_list
);
1738 spin_unlock(&fs_info
->trans_lock
);
1740 wait_event(ordered
->wait
, test_bit(BTRFS_ORDERED_COMPLETE
,
1742 btrfs_put_ordered_extent(ordered
);
1743 spin_lock(&fs_info
->trans_lock
);
1745 spin_unlock(&fs_info
->trans_lock
);
1748 int btrfs_commit_transaction(struct btrfs_trans_handle
*trans
,
1749 struct btrfs_root
*root
)
1751 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1752 struct btrfs_transaction
*prev_trans
= NULL
;
1753 struct btrfs_inode
*btree_ino
= BTRFS_I(root
->fs_info
->btree_inode
);
1756 /* Stop the commit early if ->aborted is set */
1757 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1758 ret
= cur_trans
->aborted
;
1759 btrfs_end_transaction(trans
, root
);
1763 /* make a pass through all the delayed refs we have so far
1764 * any runnings procs may add more while we are here
1766 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1768 btrfs_end_transaction(trans
, root
);
1772 btrfs_trans_release_metadata(trans
, root
);
1773 trans
->block_rsv
= NULL
;
1774 if (trans
->qgroup_reserved
) {
1775 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
1776 trans
->qgroup_reserved
= 0;
1779 cur_trans
= trans
->transaction
;
1782 * set the flushing flag so procs in this transaction have to
1783 * start sending their work down.
1785 cur_trans
->delayed_refs
.flushing
= 1;
1788 if (!list_empty(&trans
->new_bgs
))
1789 btrfs_create_pending_block_groups(trans
, root
);
1791 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1793 btrfs_end_transaction(trans
, root
);
1797 spin_lock(&root
->fs_info
->trans_lock
);
1798 list_splice(&trans
->ordered
, &cur_trans
->pending_ordered
);
1799 if (cur_trans
->state
>= TRANS_STATE_COMMIT_START
) {
1800 spin_unlock(&root
->fs_info
->trans_lock
);
1801 atomic_inc(&cur_trans
->use_count
);
1802 ret
= btrfs_end_transaction(trans
, root
);
1804 wait_for_commit(root
, cur_trans
);
1806 btrfs_put_transaction(cur_trans
);
1811 cur_trans
->state
= TRANS_STATE_COMMIT_START
;
1812 wake_up(&root
->fs_info
->transaction_blocked_wait
);
1814 if (cur_trans
->list
.prev
!= &root
->fs_info
->trans_list
) {
1815 prev_trans
= list_entry(cur_trans
->list
.prev
,
1816 struct btrfs_transaction
, list
);
1817 if (prev_trans
->state
!= TRANS_STATE_COMPLETED
) {
1818 atomic_inc(&prev_trans
->use_count
);
1819 spin_unlock(&root
->fs_info
->trans_lock
);
1821 wait_for_commit(root
, prev_trans
);
1823 btrfs_put_transaction(prev_trans
);
1825 spin_unlock(&root
->fs_info
->trans_lock
);
1828 spin_unlock(&root
->fs_info
->trans_lock
);
1831 extwriter_counter_dec(cur_trans
, trans
->type
);
1833 ret
= btrfs_start_delalloc_flush(root
->fs_info
);
1835 goto cleanup_transaction
;
1837 ret
= btrfs_run_delayed_items(trans
, root
);
1839 goto cleanup_transaction
;
1841 wait_event(cur_trans
->writer_wait
,
1842 extwriter_counter_read(cur_trans
) == 0);
1844 /* some pending stuffs might be added after the previous flush. */
1845 ret
= btrfs_run_delayed_items(trans
, root
);
1847 goto cleanup_transaction
;
1849 btrfs_wait_delalloc_flush(root
->fs_info
);
1851 btrfs_wait_pending_ordered(cur_trans
, root
->fs_info
);
1853 btrfs_scrub_pause(root
);
1855 * Ok now we need to make sure to block out any other joins while we
1856 * commit the transaction. We could have started a join before setting
1857 * COMMIT_DOING so make sure to wait for num_writers to == 1 again.
1859 spin_lock(&root
->fs_info
->trans_lock
);
1860 cur_trans
->state
= TRANS_STATE_COMMIT_DOING
;
1861 spin_unlock(&root
->fs_info
->trans_lock
);
1862 wait_event(cur_trans
->writer_wait
,
1863 atomic_read(&cur_trans
->num_writers
) == 1);
1865 /* ->aborted might be set after the previous check, so check it */
1866 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1867 ret
= cur_trans
->aborted
;
1868 goto scrub_continue
;
1871 * the reloc mutex makes sure that we stop
1872 * the balancing code from coming in and moving
1873 * extents around in the middle of the commit
1875 mutex_lock(&root
->fs_info
->reloc_mutex
);
1878 * We needn't worry about the delayed items because we will
1879 * deal with them in create_pending_snapshot(), which is the
1880 * core function of the snapshot creation.
1882 ret
= create_pending_snapshots(trans
, root
->fs_info
);
1884 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1885 goto scrub_continue
;
1889 * We insert the dir indexes of the snapshots and update the inode
1890 * of the snapshots' parents after the snapshot creation, so there
1891 * are some delayed items which are not dealt with. Now deal with
1894 * We needn't worry that this operation will corrupt the snapshots,
1895 * because all the tree which are snapshoted will be forced to COW
1896 * the nodes and leaves.
1898 ret
= btrfs_run_delayed_items(trans
, root
);
1900 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1901 goto scrub_continue
;
1904 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1906 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1907 goto scrub_continue
;
1911 * make sure none of the code above managed to slip in a
1914 btrfs_assert_delayed_root_empty(root
);
1916 WARN_ON(cur_trans
!= trans
->transaction
);
1918 /* btrfs_commit_tree_roots is responsible for getting the
1919 * various roots consistent with each other. Every pointer
1920 * in the tree of tree roots has to point to the most up to date
1921 * root for every subvolume and other tree. So, we have to keep
1922 * the tree logging code from jumping in and changing any
1925 * At this point in the commit, there can't be any tree-log
1926 * writers, but a little lower down we drop the trans mutex
1927 * and let new people in. By holding the tree_log_mutex
1928 * from now until after the super is written, we avoid races
1929 * with the tree-log code.
1931 mutex_lock(&root
->fs_info
->tree_log_mutex
);
1933 ret
= commit_fs_roots(trans
, root
);
1935 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1936 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1937 goto scrub_continue
;
1941 * Since the transaction is done, we can apply the pending changes
1942 * before the next transaction.
1944 btrfs_apply_pending_changes(root
->fs_info
);
1946 /* commit_fs_roots gets rid of all the tree log roots, it is now
1947 * safe to free the root of tree log roots
1949 btrfs_free_log_root_tree(trans
, root
->fs_info
);
1951 ret
= commit_cowonly_roots(trans
, root
);
1953 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1954 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1955 goto scrub_continue
;
1959 * The tasks which save the space cache and inode cache may also
1960 * update ->aborted, check it.
1962 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1963 ret
= cur_trans
->aborted
;
1964 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1965 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1966 goto scrub_continue
;
1969 btrfs_prepare_extent_commit(trans
, root
);
1971 cur_trans
= root
->fs_info
->running_transaction
;
1973 btrfs_set_root_node(&root
->fs_info
->tree_root
->root_item
,
1974 root
->fs_info
->tree_root
->node
);
1975 list_add_tail(&root
->fs_info
->tree_root
->dirty_list
,
1976 &cur_trans
->switch_commits
);
1978 btrfs_set_root_node(&root
->fs_info
->chunk_root
->root_item
,
1979 root
->fs_info
->chunk_root
->node
);
1980 list_add_tail(&root
->fs_info
->chunk_root
->dirty_list
,
1981 &cur_trans
->switch_commits
);
1983 switch_commit_roots(cur_trans
, root
->fs_info
);
1985 assert_qgroups_uptodate(trans
);
1986 update_super_roots(root
);
1988 btrfs_set_super_log_root(root
->fs_info
->super_copy
, 0);
1989 btrfs_set_super_log_root_level(root
->fs_info
->super_copy
, 0);
1990 memcpy(root
->fs_info
->super_for_commit
, root
->fs_info
->super_copy
,
1991 sizeof(*root
->fs_info
->super_copy
));
1993 btrfs_update_commit_device_size(root
->fs_info
);
1994 btrfs_update_commit_device_bytes_used(root
, cur_trans
);
1996 clear_bit(BTRFS_INODE_BTREE_LOG1_ERR
, &btree_ino
->runtime_flags
);
1997 clear_bit(BTRFS_INODE_BTREE_LOG2_ERR
, &btree_ino
->runtime_flags
);
1999 spin_lock(&root
->fs_info
->trans_lock
);
2000 cur_trans
->state
= TRANS_STATE_UNBLOCKED
;
2001 root
->fs_info
->running_transaction
= NULL
;
2002 spin_unlock(&root
->fs_info
->trans_lock
);
2003 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2005 wake_up(&root
->fs_info
->transaction_wait
);
2007 ret
= btrfs_write_and_wait_transaction(trans
, root
);
2009 btrfs_error(root
->fs_info
, ret
,
2010 "Error while writing out transaction");
2011 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2012 goto scrub_continue
;
2015 ret
= write_ctree_super(trans
, root
, 0);
2017 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2018 goto scrub_continue
;
2022 * the super is written, we can safely allow the tree-loggers
2023 * to go about their business
2025 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2027 btrfs_finish_extent_commit(trans
, root
);
2029 root
->fs_info
->last_trans_committed
= cur_trans
->transid
;
2031 * We needn't acquire the lock here because there is no other task
2032 * which can change it.
2034 cur_trans
->state
= TRANS_STATE_COMPLETED
;
2035 wake_up(&cur_trans
->commit_wait
);
2037 spin_lock(&root
->fs_info
->trans_lock
);
2038 list_del_init(&cur_trans
->list
);
2039 spin_unlock(&root
->fs_info
->trans_lock
);
2041 btrfs_put_transaction(cur_trans
);
2042 btrfs_put_transaction(cur_trans
);
2044 if (trans
->type
& __TRANS_FREEZABLE
)
2045 sb_end_intwrite(root
->fs_info
->sb
);
2047 trace_btrfs_transaction_commit(root
);
2049 btrfs_scrub_continue(root
);
2051 if (current
->journal_info
== trans
)
2052 current
->journal_info
= NULL
;
2054 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
2056 if (current
!= root
->fs_info
->transaction_kthread
)
2057 btrfs_run_delayed_iputs(root
);
2062 btrfs_scrub_continue(root
);
2063 cleanup_transaction
:
2064 btrfs_trans_release_metadata(trans
, root
);
2065 trans
->block_rsv
= NULL
;
2066 if (trans
->qgroup_reserved
) {
2067 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
2068 trans
->qgroup_reserved
= 0;
2070 btrfs_warn(root
->fs_info
, "Skipping commit of aborted transaction.");
2071 if (current
->journal_info
== trans
)
2072 current
->journal_info
= NULL
;
2073 cleanup_transaction(trans
, root
, ret
);
2079 * return < 0 if error
2080 * 0 if there are no more dead_roots at the time of call
2081 * 1 there are more to be processed, call me again
2083 * The return value indicates there are certainly more snapshots to delete, but
2084 * if there comes a new one during processing, it may return 0. We don't mind,
2085 * because btrfs_commit_super will poke cleaner thread and it will process it a
2086 * few seconds later.
2088 int btrfs_clean_one_deleted_snapshot(struct btrfs_root
*root
)
2091 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2093 spin_lock(&fs_info
->trans_lock
);
2094 if (list_empty(&fs_info
->dead_roots
)) {
2095 spin_unlock(&fs_info
->trans_lock
);
2098 root
= list_first_entry(&fs_info
->dead_roots
,
2099 struct btrfs_root
, root_list
);
2100 list_del_init(&root
->root_list
);
2101 spin_unlock(&fs_info
->trans_lock
);
2103 pr_debug("BTRFS: cleaner removing %llu\n", root
->objectid
);
2105 btrfs_kill_all_delayed_nodes(root
);
2107 if (btrfs_header_backref_rev(root
->node
) <
2108 BTRFS_MIXED_BACKREF_REV
)
2109 ret
= btrfs_drop_snapshot(root
, NULL
, 0, 0);
2111 ret
= btrfs_drop_snapshot(root
, NULL
, 1, 0);
2113 return (ret
< 0) ? 0 : 1;
2116 void btrfs_apply_pending_changes(struct btrfs_fs_info
*fs_info
)
2121 prev
= cmpxchg(&fs_info
->pending_changes
, 0, 0);
2125 bit
= 1 << BTRFS_PENDING_SET_INODE_MAP_CACHE
;
2127 btrfs_set_opt(fs_info
->mount_opt
, INODE_MAP_CACHE
);
2130 bit
= 1 << BTRFS_PENDING_CLEAR_INODE_MAP_CACHE
;
2132 btrfs_clear_opt(fs_info
->mount_opt
, INODE_MAP_CACHE
);
2135 bit
= 1 << BTRFS_PENDING_COMMIT
;
2137 btrfs_debug(fs_info
, "pending commit done");
2142 "unknown pending changes left 0x%lx, ignoring", prev
);