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 const 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 if (transaction
->delayed_refs
.pending_csums
)
68 printk(KERN_ERR
"pending csums is %llu\n",
69 transaction
->delayed_refs
.pending_csums
);
70 while (!list_empty(&transaction
->pending_chunks
)) {
71 struct extent_map
*em
;
73 em
= list_first_entry(&transaction
->pending_chunks
,
74 struct extent_map
, list
);
75 list_del_init(&em
->list
);
78 kmem_cache_free(btrfs_transaction_cachep
, transaction
);
82 static void clear_btree_io_tree(struct extent_io_tree
*tree
)
84 spin_lock(&tree
->lock
);
85 while (!RB_EMPTY_ROOT(&tree
->state
)) {
87 struct extent_state
*state
;
89 node
= rb_first(&tree
->state
);
90 state
= rb_entry(node
, struct extent_state
, rb_node
);
91 rb_erase(&state
->rb_node
, &tree
->state
);
92 RB_CLEAR_NODE(&state
->rb_node
);
94 * btree io trees aren't supposed to have tasks waiting for
95 * changes in the flags of extent states ever.
97 ASSERT(!waitqueue_active(&state
->wq
));
98 free_extent_state(state
);
100 cond_resched_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
->have_free_bgs
= 0;
224 cur_trans
->start_time
= get_seconds();
225 cur_trans
->dirty_bg_run
= 0;
227 cur_trans
->delayed_refs
.href_root
= RB_ROOT
;
228 atomic_set(&cur_trans
->delayed_refs
.num_entries
, 0);
229 cur_trans
->delayed_refs
.num_heads_ready
= 0;
230 cur_trans
->delayed_refs
.pending_csums
= 0;
231 cur_trans
->delayed_refs
.num_heads
= 0;
232 cur_trans
->delayed_refs
.flushing
= 0;
233 cur_trans
->delayed_refs
.run_delayed_start
= 0;
236 * although the tree mod log is per file system and not per transaction,
237 * the log must never go across transaction boundaries.
240 if (!list_empty(&fs_info
->tree_mod_seq_list
))
241 WARN(1, KERN_ERR
"BTRFS: tree_mod_seq_list not empty when "
242 "creating a fresh transaction\n");
243 if (!RB_EMPTY_ROOT(&fs_info
->tree_mod_log
))
244 WARN(1, KERN_ERR
"BTRFS: tree_mod_log rb tree not empty when "
245 "creating a fresh transaction\n");
246 atomic64_set(&fs_info
->tree_mod_seq
, 0);
248 spin_lock_init(&cur_trans
->delayed_refs
.lock
);
250 INIT_LIST_HEAD(&cur_trans
->pending_snapshots
);
251 INIT_LIST_HEAD(&cur_trans
->pending_chunks
);
252 INIT_LIST_HEAD(&cur_trans
->switch_commits
);
253 INIT_LIST_HEAD(&cur_trans
->pending_ordered
);
254 INIT_LIST_HEAD(&cur_trans
->dirty_bgs
);
255 INIT_LIST_HEAD(&cur_trans
->io_bgs
);
256 mutex_init(&cur_trans
->cache_write_mutex
);
257 cur_trans
->num_dirty_bgs
= 0;
258 spin_lock_init(&cur_trans
->dirty_bgs_lock
);
259 list_add_tail(&cur_trans
->list
, &fs_info
->trans_list
);
260 extent_io_tree_init(&cur_trans
->dirty_pages
,
261 fs_info
->btree_inode
->i_mapping
);
262 fs_info
->generation
++;
263 cur_trans
->transid
= fs_info
->generation
;
264 fs_info
->running_transaction
= cur_trans
;
265 cur_trans
->aborted
= 0;
266 spin_unlock(&fs_info
->trans_lock
);
272 * this does all the record keeping required to make sure that a reference
273 * counted root is properly recorded in a given transaction. This is required
274 * to make sure the old root from before we joined the transaction is deleted
275 * when the transaction commits
277 static int record_root_in_trans(struct btrfs_trans_handle
*trans
,
278 struct btrfs_root
*root
)
280 if (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) &&
281 root
->last_trans
< trans
->transid
) {
282 WARN_ON(root
== root
->fs_info
->extent_root
);
283 WARN_ON(root
->commit_root
!= root
->node
);
286 * see below for IN_TRANS_SETUP usage rules
287 * we have the reloc mutex held now, so there
288 * is only one writer in this function
290 set_bit(BTRFS_ROOT_IN_TRANS_SETUP
, &root
->state
);
292 /* make sure readers find IN_TRANS_SETUP before
293 * they find our root->last_trans update
297 spin_lock(&root
->fs_info
->fs_roots_radix_lock
);
298 if (root
->last_trans
== trans
->transid
) {
299 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
302 radix_tree_tag_set(&root
->fs_info
->fs_roots_radix
,
303 (unsigned long)root
->root_key
.objectid
,
304 BTRFS_ROOT_TRANS_TAG
);
305 spin_unlock(&root
->fs_info
->fs_roots_radix_lock
);
306 root
->last_trans
= trans
->transid
;
308 /* this is pretty tricky. We don't want to
309 * take the relocation lock in btrfs_record_root_in_trans
310 * unless we're really doing the first setup for this root in
313 * Normally we'd use root->last_trans as a flag to decide
314 * if we want to take the expensive mutex.
316 * But, we have to set root->last_trans before we
317 * init the relocation root, otherwise, we trip over warnings
318 * in ctree.c. The solution used here is to flag ourselves
319 * with root IN_TRANS_SETUP. When this is 1, we're still
320 * fixing up the reloc trees and everyone must wait.
322 * When this is zero, they can trust root->last_trans and fly
323 * through btrfs_record_root_in_trans without having to take the
324 * lock. smp_wmb() makes sure that all the writes above are
325 * done before we pop in the zero below
327 btrfs_init_reloc_root(trans
, root
);
328 smp_mb__before_atomic();
329 clear_bit(BTRFS_ROOT_IN_TRANS_SETUP
, &root
->state
);
335 int btrfs_record_root_in_trans(struct btrfs_trans_handle
*trans
,
336 struct btrfs_root
*root
)
338 if (!test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
))
342 * see record_root_in_trans for comments about IN_TRANS_SETUP usage
346 if (root
->last_trans
== trans
->transid
&&
347 !test_bit(BTRFS_ROOT_IN_TRANS_SETUP
, &root
->state
))
350 mutex_lock(&root
->fs_info
->reloc_mutex
);
351 record_root_in_trans(trans
, root
);
352 mutex_unlock(&root
->fs_info
->reloc_mutex
);
357 static inline int is_transaction_blocked(struct btrfs_transaction
*trans
)
359 return (trans
->state
>= TRANS_STATE_BLOCKED
&&
360 trans
->state
< TRANS_STATE_UNBLOCKED
&&
364 /* wait for commit against the current transaction to become unblocked
365 * when this is done, it is safe to start a new transaction, but the current
366 * transaction might not be fully on disk.
368 static void wait_current_trans(struct btrfs_root
*root
)
370 struct btrfs_transaction
*cur_trans
;
372 spin_lock(&root
->fs_info
->trans_lock
);
373 cur_trans
= root
->fs_info
->running_transaction
;
374 if (cur_trans
&& is_transaction_blocked(cur_trans
)) {
375 atomic_inc(&cur_trans
->use_count
);
376 spin_unlock(&root
->fs_info
->trans_lock
);
378 wait_event(root
->fs_info
->transaction_wait
,
379 cur_trans
->state
>= TRANS_STATE_UNBLOCKED
||
381 btrfs_put_transaction(cur_trans
);
383 spin_unlock(&root
->fs_info
->trans_lock
);
387 static int may_wait_transaction(struct btrfs_root
*root
, int type
)
389 if (root
->fs_info
->log_root_recovering
)
392 if (type
== TRANS_USERSPACE
)
395 if (type
== TRANS_START
&&
396 !atomic_read(&root
->fs_info
->open_ioctl_trans
))
402 static inline bool need_reserve_reloc_root(struct btrfs_root
*root
)
404 if (!root
->fs_info
->reloc_ctl
||
405 !test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) ||
406 root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
||
413 static struct btrfs_trans_handle
*
414 start_transaction(struct btrfs_root
*root
, u64 num_items
, unsigned int type
,
415 enum btrfs_reserve_flush_enum flush
)
417 struct btrfs_trans_handle
*h
;
418 struct btrfs_transaction
*cur_trans
;
420 u64 qgroup_reserved
= 0;
421 bool reloc_reserved
= false;
424 /* Send isn't supposed to start transactions. */
425 ASSERT(current
->journal_info
!= BTRFS_SEND_TRANS_STUB
);
427 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
))
428 return ERR_PTR(-EROFS
);
430 if (current
->journal_info
) {
431 WARN_ON(type
& TRANS_EXTWRITERS
);
432 h
= current
->journal_info
;
434 WARN_ON(h
->use_count
> 2);
435 h
->orig_rsv
= h
->block_rsv
;
441 * Do the reservation before we join the transaction so we can do all
442 * the appropriate flushing if need be.
444 if (num_items
> 0 && root
!= root
->fs_info
->chunk_root
) {
445 if (root
->fs_info
->quota_enabled
&&
446 is_fstree(root
->root_key
.objectid
)) {
447 qgroup_reserved
= num_items
* root
->nodesize
;
448 ret
= btrfs_qgroup_reserve(root
, qgroup_reserved
);
453 num_bytes
= btrfs_calc_trans_metadata_size(root
, num_items
);
455 * Do the reservation for the relocation root creation
457 if (need_reserve_reloc_root(root
)) {
458 num_bytes
+= root
->nodesize
;
459 reloc_reserved
= true;
462 ret
= btrfs_block_rsv_add(root
,
463 &root
->fs_info
->trans_block_rsv
,
469 h
= kmem_cache_alloc(btrfs_trans_handle_cachep
, GFP_NOFS
);
476 * If we are JOIN_NOLOCK we're already committing a transaction and
477 * waiting on this guy, so we don't need to do the sb_start_intwrite
478 * because we're already holding a ref. We need this because we could
479 * have raced in and did an fsync() on a file which can kick a commit
480 * and then we deadlock with somebody doing a freeze.
482 * If we are ATTACH, it means we just want to catch the current
483 * transaction and commit it, so we needn't do sb_start_intwrite().
485 if (type
& __TRANS_FREEZABLE
)
486 sb_start_intwrite(root
->fs_info
->sb
);
488 if (may_wait_transaction(root
, type
))
489 wait_current_trans(root
);
492 ret
= join_transaction(root
, type
);
494 wait_current_trans(root
);
495 if (unlikely(type
== TRANS_ATTACH
))
498 } while (ret
== -EBUSY
);
501 /* We must get the transaction if we are JOIN_NOLOCK. */
502 BUG_ON(type
== TRANS_JOIN_NOLOCK
);
506 cur_trans
= root
->fs_info
->running_transaction
;
508 h
->transid
= cur_trans
->transid
;
509 h
->transaction
= cur_trans
;
511 h
->bytes_reserved
= 0;
513 h
->delayed_ref_updates
= 0;
519 h
->qgroup_reserved
= 0;
520 h
->delayed_ref_elem
.seq
= 0;
522 h
->allocating_chunk
= false;
523 h
->reloc_reserved
= false;
525 INIT_LIST_HEAD(&h
->qgroup_ref_list
);
526 INIT_LIST_HEAD(&h
->new_bgs
);
527 INIT_LIST_HEAD(&h
->ordered
);
530 if (cur_trans
->state
>= TRANS_STATE_BLOCKED
&&
531 may_wait_transaction(root
, type
)) {
532 current
->journal_info
= h
;
533 btrfs_commit_transaction(h
, root
);
538 trace_btrfs_space_reservation(root
->fs_info
, "transaction",
539 h
->transid
, num_bytes
, 1);
540 h
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
541 h
->bytes_reserved
= num_bytes
;
542 h
->reloc_reserved
= reloc_reserved
;
544 h
->qgroup_reserved
= qgroup_reserved
;
547 btrfs_record_root_in_trans(h
, root
);
549 if (!current
->journal_info
&& type
!= TRANS_USERSPACE
)
550 current
->journal_info
= h
;
554 if (type
& __TRANS_FREEZABLE
)
555 sb_end_intwrite(root
->fs_info
->sb
);
556 kmem_cache_free(btrfs_trans_handle_cachep
, h
);
559 btrfs_block_rsv_release(root
, &root
->fs_info
->trans_block_rsv
,
563 btrfs_qgroup_free(root
, qgroup_reserved
);
567 struct btrfs_trans_handle
*btrfs_start_transaction(struct btrfs_root
*root
,
570 return start_transaction(root
, num_items
, TRANS_START
,
571 BTRFS_RESERVE_FLUSH_ALL
);
574 struct btrfs_trans_handle
*btrfs_start_transaction_lflush(
575 struct btrfs_root
*root
, int num_items
)
577 return start_transaction(root
, num_items
, TRANS_START
,
578 BTRFS_RESERVE_FLUSH_LIMIT
);
581 struct btrfs_trans_handle
*btrfs_join_transaction(struct btrfs_root
*root
)
583 return start_transaction(root
, 0, TRANS_JOIN
, 0);
586 struct btrfs_trans_handle
*btrfs_join_transaction_nolock(struct btrfs_root
*root
)
588 return start_transaction(root
, 0, TRANS_JOIN_NOLOCK
, 0);
591 struct btrfs_trans_handle
*btrfs_start_ioctl_transaction(struct btrfs_root
*root
)
593 return start_transaction(root
, 0, TRANS_USERSPACE
, 0);
597 * btrfs_attach_transaction() - catch the running transaction
599 * It is used when we want to commit the current the transaction, but
600 * don't want to start a new one.
602 * Note: If this function return -ENOENT, it just means there is no
603 * running transaction. But it is possible that the inactive transaction
604 * is still in the memory, not fully on disk. If you hope there is no
605 * inactive transaction in the fs when -ENOENT is returned, you should
607 * btrfs_attach_transaction_barrier()
609 struct btrfs_trans_handle
*btrfs_attach_transaction(struct btrfs_root
*root
)
611 return start_transaction(root
, 0, TRANS_ATTACH
, 0);
615 * btrfs_attach_transaction_barrier() - catch the running transaction
617 * It is similar to the above function, the differentia is this one
618 * will wait for all the inactive transactions until they fully
621 struct btrfs_trans_handle
*
622 btrfs_attach_transaction_barrier(struct btrfs_root
*root
)
624 struct btrfs_trans_handle
*trans
;
626 trans
= start_transaction(root
, 0, TRANS_ATTACH
, 0);
627 if (IS_ERR(trans
) && PTR_ERR(trans
) == -ENOENT
)
628 btrfs_wait_for_commit(root
, 0);
633 /* wait for a transaction commit to be fully complete */
634 static noinline
void wait_for_commit(struct btrfs_root
*root
,
635 struct btrfs_transaction
*commit
)
637 wait_event(commit
->commit_wait
, commit
->state
== TRANS_STATE_COMPLETED
);
640 int btrfs_wait_for_commit(struct btrfs_root
*root
, u64 transid
)
642 struct btrfs_transaction
*cur_trans
= NULL
, *t
;
646 if (transid
<= root
->fs_info
->last_trans_committed
)
649 /* find specified transaction */
650 spin_lock(&root
->fs_info
->trans_lock
);
651 list_for_each_entry(t
, &root
->fs_info
->trans_list
, list
) {
652 if (t
->transid
== transid
) {
654 atomic_inc(&cur_trans
->use_count
);
658 if (t
->transid
> transid
) {
663 spin_unlock(&root
->fs_info
->trans_lock
);
666 * The specified transaction doesn't exist, or we
667 * raced with btrfs_commit_transaction
670 if (transid
> root
->fs_info
->last_trans_committed
)
675 /* find newest transaction that is committing | committed */
676 spin_lock(&root
->fs_info
->trans_lock
);
677 list_for_each_entry_reverse(t
, &root
->fs_info
->trans_list
,
679 if (t
->state
>= TRANS_STATE_COMMIT_START
) {
680 if (t
->state
== TRANS_STATE_COMPLETED
)
683 atomic_inc(&cur_trans
->use_count
);
687 spin_unlock(&root
->fs_info
->trans_lock
);
689 goto out
; /* nothing committing|committed */
692 wait_for_commit(root
, cur_trans
);
693 btrfs_put_transaction(cur_trans
);
698 void btrfs_throttle(struct btrfs_root
*root
)
700 if (!atomic_read(&root
->fs_info
->open_ioctl_trans
))
701 wait_current_trans(root
);
704 static int should_end_transaction(struct btrfs_trans_handle
*trans
,
705 struct btrfs_root
*root
)
707 if (root
->fs_info
->global_block_rsv
.space_info
->full
&&
708 btrfs_check_space_for_delayed_refs(trans
, root
))
711 return !!btrfs_block_rsv_check(root
, &root
->fs_info
->global_block_rsv
, 5);
714 int btrfs_should_end_transaction(struct btrfs_trans_handle
*trans
,
715 struct btrfs_root
*root
)
717 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
722 if (cur_trans
->state
>= TRANS_STATE_BLOCKED
||
723 cur_trans
->delayed_refs
.flushing
)
726 updates
= trans
->delayed_ref_updates
;
727 trans
->delayed_ref_updates
= 0;
729 err
= btrfs_run_delayed_refs(trans
, root
, updates
* 2);
730 if (err
) /* Error code will also eval true */
734 return should_end_transaction(trans
, root
);
737 static int __btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
738 struct btrfs_root
*root
, int throttle
)
740 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
741 struct btrfs_fs_info
*info
= root
->fs_info
;
742 unsigned long cur
= trans
->delayed_ref_updates
;
743 int lock
= (trans
->type
!= TRANS_JOIN_NOLOCK
);
745 int must_run_delayed_refs
= 0;
747 if (trans
->use_count
> 1) {
749 trans
->block_rsv
= trans
->orig_rsv
;
753 btrfs_trans_release_metadata(trans
, root
);
754 trans
->block_rsv
= NULL
;
756 if (!list_empty(&trans
->new_bgs
))
757 btrfs_create_pending_block_groups(trans
, root
);
759 if (!list_empty(&trans
->ordered
)) {
760 spin_lock(&info
->trans_lock
);
761 list_splice(&trans
->ordered
, &cur_trans
->pending_ordered
);
762 spin_unlock(&info
->trans_lock
);
765 trans
->delayed_ref_updates
= 0;
767 must_run_delayed_refs
=
768 btrfs_should_throttle_delayed_refs(trans
, root
);
769 cur
= max_t(unsigned long, cur
, 32);
772 * don't make the caller wait if they are from a NOLOCK
773 * or ATTACH transaction, it will deadlock with commit
775 if (must_run_delayed_refs
== 1 &&
776 (trans
->type
& (__TRANS_JOIN_NOLOCK
| __TRANS_ATTACH
)))
777 must_run_delayed_refs
= 2;
780 if (trans
->qgroup_reserved
) {
782 * the same root has to be passed here between start_transaction
783 * and end_transaction. Subvolume quota depends on this.
785 btrfs_qgroup_free(trans
->root
, trans
->qgroup_reserved
);
786 trans
->qgroup_reserved
= 0;
789 btrfs_trans_release_metadata(trans
, root
);
790 trans
->block_rsv
= NULL
;
792 if (!list_empty(&trans
->new_bgs
))
793 btrfs_create_pending_block_groups(trans
, root
);
795 if (lock
&& !atomic_read(&root
->fs_info
->open_ioctl_trans
) &&
796 should_end_transaction(trans
, root
) &&
797 ACCESS_ONCE(cur_trans
->state
) == TRANS_STATE_RUNNING
) {
798 spin_lock(&info
->trans_lock
);
799 if (cur_trans
->state
== TRANS_STATE_RUNNING
)
800 cur_trans
->state
= TRANS_STATE_BLOCKED
;
801 spin_unlock(&info
->trans_lock
);
804 if (lock
&& ACCESS_ONCE(cur_trans
->state
) == TRANS_STATE_BLOCKED
) {
806 return btrfs_commit_transaction(trans
, root
);
808 wake_up_process(info
->transaction_kthread
);
811 if (trans
->type
& __TRANS_FREEZABLE
)
812 sb_end_intwrite(root
->fs_info
->sb
);
814 WARN_ON(cur_trans
!= info
->running_transaction
);
815 WARN_ON(atomic_read(&cur_trans
->num_writers
) < 1);
816 atomic_dec(&cur_trans
->num_writers
);
817 extwriter_counter_dec(cur_trans
, trans
->type
);
820 if (waitqueue_active(&cur_trans
->writer_wait
))
821 wake_up(&cur_trans
->writer_wait
);
822 btrfs_put_transaction(cur_trans
);
824 if (current
->journal_info
== trans
)
825 current
->journal_info
= NULL
;
828 btrfs_run_delayed_iputs(root
);
830 if (trans
->aborted
||
831 test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
)) {
832 wake_up_process(info
->transaction_kthread
);
835 assert_qgroups_uptodate(trans
);
837 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
838 if (must_run_delayed_refs
) {
839 btrfs_async_run_delayed_refs(root
, cur
,
840 must_run_delayed_refs
== 1);
845 int btrfs_end_transaction(struct btrfs_trans_handle
*trans
,
846 struct btrfs_root
*root
)
848 return __btrfs_end_transaction(trans
, root
, 0);
851 int btrfs_end_transaction_throttle(struct btrfs_trans_handle
*trans
,
852 struct btrfs_root
*root
)
854 return __btrfs_end_transaction(trans
, root
, 1);
858 * when btree blocks are allocated, they have some corresponding bits set for
859 * them in one of two extent_io trees. This is used to make sure all of
860 * those extents are sent to disk but does not wait on them
862 int btrfs_write_marked_extents(struct btrfs_root
*root
,
863 struct extent_io_tree
*dirty_pages
, int mark
)
867 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
868 struct extent_state
*cached_state
= NULL
;
872 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
873 mark
, &cached_state
)) {
874 bool wait_writeback
= false;
876 err
= convert_extent_bit(dirty_pages
, start
, end
,
878 mark
, &cached_state
, GFP_NOFS
);
880 * convert_extent_bit can return -ENOMEM, which is most of the
881 * time a temporary error. So when it happens, ignore the error
882 * and wait for writeback of this range to finish - because we
883 * failed to set the bit EXTENT_NEED_WAIT for the range, a call
884 * to btrfs_wait_marked_extents() would not know that writeback
885 * for this range started and therefore wouldn't wait for it to
886 * finish - we don't want to commit a superblock that points to
887 * btree nodes/leafs for which writeback hasn't finished yet
888 * (and without errors).
889 * We cleanup any entries left in the io tree when committing
890 * the transaction (through clear_btree_io_tree()).
892 if (err
== -ENOMEM
) {
894 wait_writeback
= true;
897 err
= filemap_fdatawrite_range(mapping
, start
, end
);
900 else if (wait_writeback
)
901 werr
= filemap_fdatawait_range(mapping
, start
, end
);
902 free_extent_state(cached_state
);
911 * when btree blocks are allocated, they have some corresponding bits set for
912 * them in one of two extent_io trees. This is used to make sure all of
913 * those extents are on disk for transaction or log commit. We wait
914 * on all the pages and clear them from the dirty pages state tree
916 int btrfs_wait_marked_extents(struct btrfs_root
*root
,
917 struct extent_io_tree
*dirty_pages
, int mark
)
921 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
922 struct extent_state
*cached_state
= NULL
;
925 struct btrfs_inode
*btree_ino
= BTRFS_I(root
->fs_info
->btree_inode
);
928 while (!find_first_extent_bit(dirty_pages
, start
, &start
, &end
,
929 EXTENT_NEED_WAIT
, &cached_state
)) {
931 * Ignore -ENOMEM errors returned by clear_extent_bit().
932 * When committing the transaction, we'll remove any entries
933 * left in the io tree. For a log commit, we don't remove them
934 * after committing the log because the tree can be accessed
935 * concurrently - we do it only at transaction commit time when
936 * it's safe to do it (through clear_btree_io_tree()).
938 err
= clear_extent_bit(dirty_pages
, start
, end
,
940 0, 0, &cached_state
, GFP_NOFS
);
944 err
= filemap_fdatawait_range(mapping
, start
, end
);
947 free_extent_state(cached_state
);
955 if (root
->root_key
.objectid
== BTRFS_TREE_LOG_OBJECTID
) {
956 if ((mark
& EXTENT_DIRTY
) &&
957 test_and_clear_bit(BTRFS_INODE_BTREE_LOG1_ERR
,
958 &btree_ino
->runtime_flags
))
961 if ((mark
& EXTENT_NEW
) &&
962 test_and_clear_bit(BTRFS_INODE_BTREE_LOG2_ERR
,
963 &btree_ino
->runtime_flags
))
966 if (test_and_clear_bit(BTRFS_INODE_BTREE_ERR
,
967 &btree_ino
->runtime_flags
))
978 * when btree blocks are allocated, they have some corresponding bits set for
979 * them in one of two extent_io trees. This is used to make sure all of
980 * those extents are on disk for transaction or log commit
982 static int btrfs_write_and_wait_marked_extents(struct btrfs_root
*root
,
983 struct extent_io_tree
*dirty_pages
, int mark
)
987 struct blk_plug plug
;
989 blk_start_plug(&plug
);
990 ret
= btrfs_write_marked_extents(root
, dirty_pages
, mark
);
991 blk_finish_plug(&plug
);
992 ret2
= btrfs_wait_marked_extents(root
, dirty_pages
, mark
);
1001 static int btrfs_write_and_wait_transaction(struct btrfs_trans_handle
*trans
,
1002 struct btrfs_root
*root
)
1006 ret
= btrfs_write_and_wait_marked_extents(root
,
1007 &trans
->transaction
->dirty_pages
,
1009 clear_btree_io_tree(&trans
->transaction
->dirty_pages
);
1015 * this is used to update the root pointer in the tree of tree roots.
1017 * But, in the case of the extent allocation tree, updating the root
1018 * pointer may allocate blocks which may change the root of the extent
1021 * So, this loops and repeats and makes sure the cowonly root didn't
1022 * change while the root pointer was being updated in the metadata.
1024 static int update_cowonly_root(struct btrfs_trans_handle
*trans
,
1025 struct btrfs_root
*root
)
1028 u64 old_root_bytenr
;
1030 struct btrfs_root
*tree_root
= root
->fs_info
->tree_root
;
1032 old_root_used
= btrfs_root_used(&root
->root_item
);
1035 old_root_bytenr
= btrfs_root_bytenr(&root
->root_item
);
1036 if (old_root_bytenr
== root
->node
->start
&&
1037 old_root_used
== btrfs_root_used(&root
->root_item
))
1040 btrfs_set_root_node(&root
->root_item
, root
->node
);
1041 ret
= btrfs_update_root(trans
, tree_root
,
1047 old_root_used
= btrfs_root_used(&root
->root_item
);
1054 * update all the cowonly tree roots on disk
1056 * The error handling in this function may not be obvious. Any of the
1057 * failures will cause the file system to go offline. We still need
1058 * to clean up the delayed refs.
1060 static noinline
int commit_cowonly_roots(struct btrfs_trans_handle
*trans
,
1061 struct btrfs_root
*root
)
1063 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1064 struct list_head
*dirty_bgs
= &trans
->transaction
->dirty_bgs
;
1065 struct list_head
*io_bgs
= &trans
->transaction
->io_bgs
;
1066 struct list_head
*next
;
1067 struct extent_buffer
*eb
;
1070 eb
= btrfs_lock_root_node(fs_info
->tree_root
);
1071 ret
= btrfs_cow_block(trans
, fs_info
->tree_root
, eb
, NULL
,
1073 btrfs_tree_unlock(eb
);
1074 free_extent_buffer(eb
);
1079 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1083 ret
= btrfs_run_dev_stats(trans
, root
->fs_info
);
1086 ret
= btrfs_run_dev_replace(trans
, root
->fs_info
);
1089 ret
= btrfs_run_qgroups(trans
, root
->fs_info
);
1093 ret
= btrfs_setup_space_cache(trans
, root
);
1097 /* run_qgroups might have added some more refs */
1098 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1102 while (!list_empty(&fs_info
->dirty_cowonly_roots
)) {
1103 next
= fs_info
->dirty_cowonly_roots
.next
;
1104 list_del_init(next
);
1105 root
= list_entry(next
, struct btrfs_root
, dirty_list
);
1106 clear_bit(BTRFS_ROOT_DIRTY
, &root
->state
);
1108 if (root
!= fs_info
->extent_root
)
1109 list_add_tail(&root
->dirty_list
,
1110 &trans
->transaction
->switch_commits
);
1111 ret
= update_cowonly_root(trans
, root
);
1114 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1119 while (!list_empty(dirty_bgs
) || !list_empty(io_bgs
)) {
1120 ret
= btrfs_write_dirty_block_groups(trans
, root
);
1123 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1128 if (!list_empty(&fs_info
->dirty_cowonly_roots
))
1131 list_add_tail(&fs_info
->extent_root
->dirty_list
,
1132 &trans
->transaction
->switch_commits
);
1133 btrfs_after_dev_replace_commit(fs_info
);
1139 * dead roots are old snapshots that need to be deleted. This allocates
1140 * a dirty root struct and adds it into the list of dead roots that need to
1143 void btrfs_add_dead_root(struct btrfs_root
*root
)
1145 spin_lock(&root
->fs_info
->trans_lock
);
1146 if (list_empty(&root
->root_list
))
1147 list_add_tail(&root
->root_list
, &root
->fs_info
->dead_roots
);
1148 spin_unlock(&root
->fs_info
->trans_lock
);
1152 * update all the cowonly tree roots on disk
1154 static noinline
int commit_fs_roots(struct btrfs_trans_handle
*trans
,
1155 struct btrfs_root
*root
)
1157 struct btrfs_root
*gang
[8];
1158 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1163 spin_lock(&fs_info
->fs_roots_radix_lock
);
1165 ret
= radix_tree_gang_lookup_tag(&fs_info
->fs_roots_radix
,
1168 BTRFS_ROOT_TRANS_TAG
);
1171 for (i
= 0; i
< ret
; i
++) {
1173 radix_tree_tag_clear(&fs_info
->fs_roots_radix
,
1174 (unsigned long)root
->root_key
.objectid
,
1175 BTRFS_ROOT_TRANS_TAG
);
1176 spin_unlock(&fs_info
->fs_roots_radix_lock
);
1178 btrfs_free_log(trans
, root
);
1179 btrfs_update_reloc_root(trans
, root
);
1180 btrfs_orphan_commit_root(trans
, root
);
1182 btrfs_save_ino_cache(root
, trans
);
1184 /* see comments in should_cow_block() */
1185 clear_bit(BTRFS_ROOT_FORCE_COW
, &root
->state
);
1186 smp_mb__after_atomic();
1188 if (root
->commit_root
!= root
->node
) {
1189 list_add_tail(&root
->dirty_list
,
1190 &trans
->transaction
->switch_commits
);
1191 btrfs_set_root_node(&root
->root_item
,
1195 err
= btrfs_update_root(trans
, fs_info
->tree_root
,
1198 spin_lock(&fs_info
->fs_roots_radix_lock
);
1203 spin_unlock(&fs_info
->fs_roots_radix_lock
);
1208 * defrag a given btree.
1209 * Every leaf in the btree is read and defragged.
1211 int btrfs_defrag_root(struct btrfs_root
*root
)
1213 struct btrfs_fs_info
*info
= root
->fs_info
;
1214 struct btrfs_trans_handle
*trans
;
1217 if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING
, &root
->state
))
1221 trans
= btrfs_start_transaction(root
, 0);
1223 return PTR_ERR(trans
);
1225 ret
= btrfs_defrag_leaves(trans
, root
);
1227 btrfs_end_transaction(trans
, root
);
1228 btrfs_btree_balance_dirty(info
->tree_root
);
1231 if (btrfs_fs_closing(root
->fs_info
) || ret
!= -EAGAIN
)
1234 if (btrfs_defrag_cancelled(root
->fs_info
)) {
1235 pr_debug("BTRFS: defrag_root cancelled\n");
1240 clear_bit(BTRFS_ROOT_DEFRAG_RUNNING
, &root
->state
);
1245 * new snapshots need to be created at a very specific time in the
1246 * transaction commit. This does the actual creation.
1249 * If the error which may affect the commitment of the current transaction
1250 * happens, we should return the error number. If the error which just affect
1251 * the creation of the pending snapshots, just return 0.
1253 static noinline
int create_pending_snapshot(struct btrfs_trans_handle
*trans
,
1254 struct btrfs_fs_info
*fs_info
,
1255 struct btrfs_pending_snapshot
*pending
)
1257 struct btrfs_key key
;
1258 struct btrfs_root_item
*new_root_item
;
1259 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
1260 struct btrfs_root
*root
= pending
->root
;
1261 struct btrfs_root
*parent_root
;
1262 struct btrfs_block_rsv
*rsv
;
1263 struct inode
*parent_inode
;
1264 struct btrfs_path
*path
;
1265 struct btrfs_dir_item
*dir_item
;
1266 struct dentry
*dentry
;
1267 struct extent_buffer
*tmp
;
1268 struct extent_buffer
*old
;
1269 struct timespec cur_time
= CURRENT_TIME
;
1277 path
= btrfs_alloc_path();
1279 pending
->error
= -ENOMEM
;
1283 new_root_item
= kmalloc(sizeof(*new_root_item
), GFP_NOFS
);
1284 if (!new_root_item
) {
1285 pending
->error
= -ENOMEM
;
1286 goto root_item_alloc_fail
;
1289 pending
->error
= btrfs_find_free_objectid(tree_root
, &objectid
);
1291 goto no_free_objectid
;
1293 btrfs_reloc_pre_snapshot(trans
, pending
, &to_reserve
);
1295 if (to_reserve
> 0) {
1296 pending
->error
= btrfs_block_rsv_add(root
,
1297 &pending
->block_rsv
,
1299 BTRFS_RESERVE_NO_FLUSH
);
1301 goto no_free_objectid
;
1304 key
.objectid
= objectid
;
1305 key
.offset
= (u64
)-1;
1306 key
.type
= BTRFS_ROOT_ITEM_KEY
;
1308 rsv
= trans
->block_rsv
;
1309 trans
->block_rsv
= &pending
->block_rsv
;
1310 trans
->bytes_reserved
= trans
->block_rsv
->reserved
;
1312 dentry
= pending
->dentry
;
1313 parent_inode
= pending
->dir
;
1314 parent_root
= BTRFS_I(parent_inode
)->root
;
1315 record_root_in_trans(trans
, parent_root
);
1318 * insert the directory item
1320 ret
= btrfs_set_inode_index(parent_inode
, &index
);
1321 BUG_ON(ret
); /* -ENOMEM */
1323 /* check if there is a file/dir which has the same name. */
1324 dir_item
= btrfs_lookup_dir_item(NULL
, parent_root
, path
,
1325 btrfs_ino(parent_inode
),
1326 dentry
->d_name
.name
,
1327 dentry
->d_name
.len
, 0);
1328 if (dir_item
!= NULL
&& !IS_ERR(dir_item
)) {
1329 pending
->error
= -EEXIST
;
1330 goto dir_item_existed
;
1331 } else if (IS_ERR(dir_item
)) {
1332 ret
= PTR_ERR(dir_item
);
1333 btrfs_abort_transaction(trans
, root
, ret
);
1336 btrfs_release_path(path
);
1339 * pull in the delayed directory update
1340 * and the delayed inode item
1341 * otherwise we corrupt the FS during
1344 ret
= btrfs_run_delayed_items(trans
, root
);
1345 if (ret
) { /* Transaction aborted */
1346 btrfs_abort_transaction(trans
, root
, ret
);
1350 record_root_in_trans(trans
, root
);
1351 btrfs_set_root_last_snapshot(&root
->root_item
, trans
->transid
);
1352 memcpy(new_root_item
, &root
->root_item
, sizeof(*new_root_item
));
1353 btrfs_check_and_init_root_item(new_root_item
);
1355 root_flags
= btrfs_root_flags(new_root_item
);
1356 if (pending
->readonly
)
1357 root_flags
|= BTRFS_ROOT_SUBVOL_RDONLY
;
1359 root_flags
&= ~BTRFS_ROOT_SUBVOL_RDONLY
;
1360 btrfs_set_root_flags(new_root_item
, root_flags
);
1362 btrfs_set_root_generation_v2(new_root_item
,
1364 uuid_le_gen(&new_uuid
);
1365 memcpy(new_root_item
->uuid
, new_uuid
.b
, BTRFS_UUID_SIZE
);
1366 memcpy(new_root_item
->parent_uuid
, root
->root_item
.uuid
,
1368 if (!(root_flags
& BTRFS_ROOT_SUBVOL_RDONLY
)) {
1369 memset(new_root_item
->received_uuid
, 0,
1370 sizeof(new_root_item
->received_uuid
));
1371 memset(&new_root_item
->stime
, 0, sizeof(new_root_item
->stime
));
1372 memset(&new_root_item
->rtime
, 0, sizeof(new_root_item
->rtime
));
1373 btrfs_set_root_stransid(new_root_item
, 0);
1374 btrfs_set_root_rtransid(new_root_item
, 0);
1376 btrfs_set_stack_timespec_sec(&new_root_item
->otime
, cur_time
.tv_sec
);
1377 btrfs_set_stack_timespec_nsec(&new_root_item
->otime
, cur_time
.tv_nsec
);
1378 btrfs_set_root_otransid(new_root_item
, trans
->transid
);
1380 old
= btrfs_lock_root_node(root
);
1381 ret
= btrfs_cow_block(trans
, root
, old
, NULL
, 0, &old
);
1383 btrfs_tree_unlock(old
);
1384 free_extent_buffer(old
);
1385 btrfs_abort_transaction(trans
, root
, ret
);
1389 btrfs_set_lock_blocking(old
);
1391 ret
= btrfs_copy_root(trans
, root
, old
, &tmp
, objectid
);
1392 /* clean up in any case */
1393 btrfs_tree_unlock(old
);
1394 free_extent_buffer(old
);
1396 btrfs_abort_transaction(trans
, root
, ret
);
1401 * We need to flush delayed refs in order to make sure all of our quota
1402 * operations have been done before we call btrfs_qgroup_inherit.
1404 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1406 btrfs_abort_transaction(trans
, root
, ret
);
1410 ret
= btrfs_qgroup_inherit(trans
, fs_info
,
1411 root
->root_key
.objectid
,
1412 objectid
, pending
->inherit
);
1414 btrfs_abort_transaction(trans
, root
, ret
);
1418 /* see comments in should_cow_block() */
1419 set_bit(BTRFS_ROOT_FORCE_COW
, &root
->state
);
1422 btrfs_set_root_node(new_root_item
, tmp
);
1423 /* record when the snapshot was created in key.offset */
1424 key
.offset
= trans
->transid
;
1425 ret
= btrfs_insert_root(trans
, tree_root
, &key
, new_root_item
);
1426 btrfs_tree_unlock(tmp
);
1427 free_extent_buffer(tmp
);
1429 btrfs_abort_transaction(trans
, root
, ret
);
1434 * insert root back/forward references
1436 ret
= btrfs_add_root_ref(trans
, tree_root
, objectid
,
1437 parent_root
->root_key
.objectid
,
1438 btrfs_ino(parent_inode
), index
,
1439 dentry
->d_name
.name
, dentry
->d_name
.len
);
1441 btrfs_abort_transaction(trans
, root
, ret
);
1445 key
.offset
= (u64
)-1;
1446 pending
->snap
= btrfs_read_fs_root_no_name(root
->fs_info
, &key
);
1447 if (IS_ERR(pending
->snap
)) {
1448 ret
= PTR_ERR(pending
->snap
);
1449 btrfs_abort_transaction(trans
, root
, ret
);
1453 ret
= btrfs_reloc_post_snapshot(trans
, pending
);
1455 btrfs_abort_transaction(trans
, root
, ret
);
1459 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1461 btrfs_abort_transaction(trans
, root
, ret
);
1465 ret
= btrfs_insert_dir_item(trans
, parent_root
,
1466 dentry
->d_name
.name
, dentry
->d_name
.len
,
1468 BTRFS_FT_DIR
, index
);
1469 /* We have check then name at the beginning, so it is impossible. */
1470 BUG_ON(ret
== -EEXIST
|| ret
== -EOVERFLOW
);
1472 btrfs_abort_transaction(trans
, root
, ret
);
1476 btrfs_i_size_write(parent_inode
, parent_inode
->i_size
+
1477 dentry
->d_name
.len
* 2);
1478 parent_inode
->i_mtime
= parent_inode
->i_ctime
= CURRENT_TIME
;
1479 ret
= btrfs_update_inode_fallback(trans
, parent_root
, parent_inode
);
1481 btrfs_abort_transaction(trans
, root
, ret
);
1484 ret
= btrfs_uuid_tree_add(trans
, fs_info
->uuid_root
, new_uuid
.b
,
1485 BTRFS_UUID_KEY_SUBVOL
, objectid
);
1487 btrfs_abort_transaction(trans
, root
, ret
);
1490 if (!btrfs_is_empty_uuid(new_root_item
->received_uuid
)) {
1491 ret
= btrfs_uuid_tree_add(trans
, fs_info
->uuid_root
,
1492 new_root_item
->received_uuid
,
1493 BTRFS_UUID_KEY_RECEIVED_SUBVOL
,
1495 if (ret
&& ret
!= -EEXIST
) {
1496 btrfs_abort_transaction(trans
, root
, ret
);
1501 pending
->error
= ret
;
1503 trans
->block_rsv
= rsv
;
1504 trans
->bytes_reserved
= 0;
1506 kfree(new_root_item
);
1507 root_item_alloc_fail
:
1508 btrfs_free_path(path
);
1513 * create all the snapshots we've scheduled for creation
1515 static noinline
int create_pending_snapshots(struct btrfs_trans_handle
*trans
,
1516 struct btrfs_fs_info
*fs_info
)
1518 struct btrfs_pending_snapshot
*pending
, *next
;
1519 struct list_head
*head
= &trans
->transaction
->pending_snapshots
;
1522 list_for_each_entry_safe(pending
, next
, head
, list
) {
1523 list_del(&pending
->list
);
1524 ret
= create_pending_snapshot(trans
, fs_info
, pending
);
1531 static void update_super_roots(struct btrfs_root
*root
)
1533 struct btrfs_root_item
*root_item
;
1534 struct btrfs_super_block
*super
;
1536 super
= root
->fs_info
->super_copy
;
1538 root_item
= &root
->fs_info
->chunk_root
->root_item
;
1539 super
->chunk_root
= root_item
->bytenr
;
1540 super
->chunk_root_generation
= root_item
->generation
;
1541 super
->chunk_root_level
= root_item
->level
;
1543 root_item
= &root
->fs_info
->tree_root
->root_item
;
1544 super
->root
= root_item
->bytenr
;
1545 super
->generation
= root_item
->generation
;
1546 super
->root_level
= root_item
->level
;
1547 if (btrfs_test_opt(root
, SPACE_CACHE
))
1548 super
->cache_generation
= root_item
->generation
;
1549 if (root
->fs_info
->update_uuid_tree_gen
)
1550 super
->uuid_tree_generation
= root_item
->generation
;
1553 int btrfs_transaction_in_commit(struct btrfs_fs_info
*info
)
1555 struct btrfs_transaction
*trans
;
1558 spin_lock(&info
->trans_lock
);
1559 trans
= info
->running_transaction
;
1561 ret
= (trans
->state
>= TRANS_STATE_COMMIT_START
);
1562 spin_unlock(&info
->trans_lock
);
1566 int btrfs_transaction_blocked(struct btrfs_fs_info
*info
)
1568 struct btrfs_transaction
*trans
;
1571 spin_lock(&info
->trans_lock
);
1572 trans
= info
->running_transaction
;
1574 ret
= is_transaction_blocked(trans
);
1575 spin_unlock(&info
->trans_lock
);
1580 * wait for the current transaction commit to start and block subsequent
1583 static void wait_current_trans_commit_start(struct btrfs_root
*root
,
1584 struct btrfs_transaction
*trans
)
1586 wait_event(root
->fs_info
->transaction_blocked_wait
,
1587 trans
->state
>= TRANS_STATE_COMMIT_START
||
1592 * wait for the current transaction to start and then become unblocked.
1595 static void wait_current_trans_commit_start_and_unblock(struct btrfs_root
*root
,
1596 struct btrfs_transaction
*trans
)
1598 wait_event(root
->fs_info
->transaction_wait
,
1599 trans
->state
>= TRANS_STATE_UNBLOCKED
||
1604 * commit transactions asynchronously. once btrfs_commit_transaction_async
1605 * returns, any subsequent transaction will not be allowed to join.
1607 struct btrfs_async_commit
{
1608 struct btrfs_trans_handle
*newtrans
;
1609 struct btrfs_root
*root
;
1610 struct work_struct work
;
1613 static void do_async_commit(struct work_struct
*work
)
1615 struct btrfs_async_commit
*ac
=
1616 container_of(work
, struct btrfs_async_commit
, work
);
1619 * We've got freeze protection passed with the transaction.
1620 * Tell lockdep about it.
1622 if (ac
->newtrans
->type
& __TRANS_FREEZABLE
)
1624 &ac
->root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1627 current
->journal_info
= ac
->newtrans
;
1629 btrfs_commit_transaction(ac
->newtrans
, ac
->root
);
1633 int btrfs_commit_transaction_async(struct btrfs_trans_handle
*trans
,
1634 struct btrfs_root
*root
,
1635 int wait_for_unblock
)
1637 struct btrfs_async_commit
*ac
;
1638 struct btrfs_transaction
*cur_trans
;
1640 ac
= kmalloc(sizeof(*ac
), GFP_NOFS
);
1644 INIT_WORK(&ac
->work
, do_async_commit
);
1646 ac
->newtrans
= btrfs_join_transaction(root
);
1647 if (IS_ERR(ac
->newtrans
)) {
1648 int err
= PTR_ERR(ac
->newtrans
);
1653 /* take transaction reference */
1654 cur_trans
= trans
->transaction
;
1655 atomic_inc(&cur_trans
->use_count
);
1657 btrfs_end_transaction(trans
, root
);
1660 * Tell lockdep we've released the freeze rwsem, since the
1661 * async commit thread will be the one to unlock it.
1663 if (ac
->newtrans
->type
& __TRANS_FREEZABLE
)
1665 &root
->fs_info
->sb
->s_writers
.lock_map
[SB_FREEZE_FS
-1],
1668 schedule_work(&ac
->work
);
1670 /* wait for transaction to start and unblock */
1671 if (wait_for_unblock
)
1672 wait_current_trans_commit_start_and_unblock(root
, cur_trans
);
1674 wait_current_trans_commit_start(root
, cur_trans
);
1676 if (current
->journal_info
== trans
)
1677 current
->journal_info
= NULL
;
1679 btrfs_put_transaction(cur_trans
);
1684 static void cleanup_transaction(struct btrfs_trans_handle
*trans
,
1685 struct btrfs_root
*root
, int err
)
1687 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1690 WARN_ON(trans
->use_count
> 1);
1692 btrfs_abort_transaction(trans
, root
, err
);
1694 spin_lock(&root
->fs_info
->trans_lock
);
1697 * If the transaction is removed from the list, it means this
1698 * transaction has been committed successfully, so it is impossible
1699 * to call the cleanup function.
1701 BUG_ON(list_empty(&cur_trans
->list
));
1703 list_del_init(&cur_trans
->list
);
1704 if (cur_trans
== root
->fs_info
->running_transaction
) {
1705 cur_trans
->state
= TRANS_STATE_COMMIT_DOING
;
1706 spin_unlock(&root
->fs_info
->trans_lock
);
1707 wait_event(cur_trans
->writer_wait
,
1708 atomic_read(&cur_trans
->num_writers
) == 1);
1710 spin_lock(&root
->fs_info
->trans_lock
);
1712 spin_unlock(&root
->fs_info
->trans_lock
);
1714 btrfs_cleanup_one_transaction(trans
->transaction
, root
);
1716 spin_lock(&root
->fs_info
->trans_lock
);
1717 if (cur_trans
== root
->fs_info
->running_transaction
)
1718 root
->fs_info
->running_transaction
= NULL
;
1719 spin_unlock(&root
->fs_info
->trans_lock
);
1721 if (trans
->type
& __TRANS_FREEZABLE
)
1722 sb_end_intwrite(root
->fs_info
->sb
);
1723 btrfs_put_transaction(cur_trans
);
1724 btrfs_put_transaction(cur_trans
);
1726 trace_btrfs_transaction_commit(root
);
1728 if (current
->journal_info
== trans
)
1729 current
->journal_info
= NULL
;
1730 btrfs_scrub_cancel(root
->fs_info
);
1732 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
1735 static inline int btrfs_start_delalloc_flush(struct btrfs_fs_info
*fs_info
)
1737 if (btrfs_test_opt(fs_info
->tree_root
, FLUSHONCOMMIT
))
1738 return btrfs_start_delalloc_roots(fs_info
, 1, -1);
1742 static inline void btrfs_wait_delalloc_flush(struct btrfs_fs_info
*fs_info
)
1744 if (btrfs_test_opt(fs_info
->tree_root
, FLUSHONCOMMIT
))
1745 btrfs_wait_ordered_roots(fs_info
, -1);
1749 btrfs_wait_pending_ordered(struct btrfs_transaction
*cur_trans
,
1750 struct btrfs_fs_info
*fs_info
)
1752 struct btrfs_ordered_extent
*ordered
;
1754 spin_lock(&fs_info
->trans_lock
);
1755 while (!list_empty(&cur_trans
->pending_ordered
)) {
1756 ordered
= list_first_entry(&cur_trans
->pending_ordered
,
1757 struct btrfs_ordered_extent
,
1759 list_del_init(&ordered
->trans_list
);
1760 spin_unlock(&fs_info
->trans_lock
);
1762 wait_event(ordered
->wait
, test_bit(BTRFS_ORDERED_COMPLETE
,
1764 btrfs_put_ordered_extent(ordered
);
1765 spin_lock(&fs_info
->trans_lock
);
1767 spin_unlock(&fs_info
->trans_lock
);
1770 int btrfs_commit_transaction(struct btrfs_trans_handle
*trans
,
1771 struct btrfs_root
*root
)
1773 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
1774 struct btrfs_transaction
*prev_trans
= NULL
;
1775 struct btrfs_inode
*btree_ino
= BTRFS_I(root
->fs_info
->btree_inode
);
1778 /* Stop the commit early if ->aborted is set */
1779 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1780 ret
= cur_trans
->aborted
;
1781 btrfs_end_transaction(trans
, root
);
1785 /* make a pass through all the delayed refs we have so far
1786 * any runnings procs may add more while we are here
1788 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1790 btrfs_end_transaction(trans
, root
);
1794 btrfs_trans_release_metadata(trans
, root
);
1795 trans
->block_rsv
= NULL
;
1796 if (trans
->qgroup_reserved
) {
1797 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
1798 trans
->qgroup_reserved
= 0;
1801 cur_trans
= trans
->transaction
;
1804 * set the flushing flag so procs in this transaction have to
1805 * start sending their work down.
1807 cur_trans
->delayed_refs
.flushing
= 1;
1810 if (!list_empty(&trans
->new_bgs
))
1811 btrfs_create_pending_block_groups(trans
, root
);
1813 ret
= btrfs_run_delayed_refs(trans
, root
, 0);
1815 btrfs_end_transaction(trans
, root
);
1819 if (!cur_trans
->dirty_bg_run
) {
1822 /* this mutex is also taken before trying to set
1823 * block groups readonly. We need to make sure
1824 * that nobody has set a block group readonly
1825 * after a extents from that block group have been
1826 * allocated for cache files. btrfs_set_block_group_ro
1827 * will wait for the transaction to commit if it
1828 * finds dirty_bg_run = 1
1830 * The dirty_bg_run flag is also used to make sure only
1831 * one process starts all the block group IO. It wouldn't
1832 * hurt to have more than one go through, but there's no
1833 * real advantage to it either.
1835 mutex_lock(&root
->fs_info
->ro_block_group_mutex
);
1836 if (!cur_trans
->dirty_bg_run
) {
1838 cur_trans
->dirty_bg_run
= 1;
1840 mutex_unlock(&root
->fs_info
->ro_block_group_mutex
);
1843 ret
= btrfs_start_dirty_block_groups(trans
, root
);
1846 btrfs_end_transaction(trans
, root
);
1850 spin_lock(&root
->fs_info
->trans_lock
);
1851 list_splice(&trans
->ordered
, &cur_trans
->pending_ordered
);
1852 if (cur_trans
->state
>= TRANS_STATE_COMMIT_START
) {
1853 spin_unlock(&root
->fs_info
->trans_lock
);
1854 atomic_inc(&cur_trans
->use_count
);
1855 ret
= btrfs_end_transaction(trans
, root
);
1857 wait_for_commit(root
, cur_trans
);
1859 if (unlikely(cur_trans
->aborted
))
1860 ret
= cur_trans
->aborted
;
1862 btrfs_put_transaction(cur_trans
);
1867 cur_trans
->state
= TRANS_STATE_COMMIT_START
;
1868 wake_up(&root
->fs_info
->transaction_blocked_wait
);
1870 if (cur_trans
->list
.prev
!= &root
->fs_info
->trans_list
) {
1871 prev_trans
= list_entry(cur_trans
->list
.prev
,
1872 struct btrfs_transaction
, list
);
1873 if (prev_trans
->state
!= TRANS_STATE_COMPLETED
) {
1874 atomic_inc(&prev_trans
->use_count
);
1875 spin_unlock(&root
->fs_info
->trans_lock
);
1877 wait_for_commit(root
, prev_trans
);
1879 btrfs_put_transaction(prev_trans
);
1881 spin_unlock(&root
->fs_info
->trans_lock
);
1884 spin_unlock(&root
->fs_info
->trans_lock
);
1887 extwriter_counter_dec(cur_trans
, trans
->type
);
1889 ret
= btrfs_start_delalloc_flush(root
->fs_info
);
1891 goto cleanup_transaction
;
1893 ret
= btrfs_run_delayed_items(trans
, root
);
1895 goto cleanup_transaction
;
1897 wait_event(cur_trans
->writer_wait
,
1898 extwriter_counter_read(cur_trans
) == 0);
1900 /* some pending stuffs might be added after the previous flush. */
1901 ret
= btrfs_run_delayed_items(trans
, root
);
1903 goto cleanup_transaction
;
1905 btrfs_wait_delalloc_flush(root
->fs_info
);
1907 btrfs_wait_pending_ordered(cur_trans
, root
->fs_info
);
1909 btrfs_scrub_pause(root
);
1911 * Ok now we need to make sure to block out any other joins while we
1912 * commit the transaction. We could have started a join before setting
1913 * COMMIT_DOING so make sure to wait for num_writers to == 1 again.
1915 spin_lock(&root
->fs_info
->trans_lock
);
1916 cur_trans
->state
= TRANS_STATE_COMMIT_DOING
;
1917 spin_unlock(&root
->fs_info
->trans_lock
);
1918 wait_event(cur_trans
->writer_wait
,
1919 atomic_read(&cur_trans
->num_writers
) == 1);
1921 /* ->aborted might be set after the previous check, so check it */
1922 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
1923 ret
= cur_trans
->aborted
;
1924 goto scrub_continue
;
1927 * the reloc mutex makes sure that we stop
1928 * the balancing code from coming in and moving
1929 * extents around in the middle of the commit
1931 mutex_lock(&root
->fs_info
->reloc_mutex
);
1934 * We needn't worry about the delayed items because we will
1935 * deal with them in create_pending_snapshot(), which is the
1936 * core function of the snapshot creation.
1938 ret
= create_pending_snapshots(trans
, root
->fs_info
);
1940 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1941 goto scrub_continue
;
1945 * We insert the dir indexes of the snapshots and update the inode
1946 * of the snapshots' parents after the snapshot creation, so there
1947 * are some delayed items which are not dealt with. Now deal with
1950 * We needn't worry that this operation will corrupt the snapshots,
1951 * because all the tree which are snapshoted will be forced to COW
1952 * the nodes and leaves.
1954 ret
= btrfs_run_delayed_items(trans
, root
);
1956 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1957 goto scrub_continue
;
1960 ret
= btrfs_run_delayed_refs(trans
, root
, (unsigned long)-1);
1962 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1963 goto scrub_continue
;
1967 * make sure none of the code above managed to slip in a
1970 btrfs_assert_delayed_root_empty(root
);
1972 WARN_ON(cur_trans
!= trans
->transaction
);
1974 /* btrfs_commit_tree_roots is responsible for getting the
1975 * various roots consistent with each other. Every pointer
1976 * in the tree of tree roots has to point to the most up to date
1977 * root for every subvolume and other tree. So, we have to keep
1978 * the tree logging code from jumping in and changing any
1981 * At this point in the commit, there can't be any tree-log
1982 * writers, but a little lower down we drop the trans mutex
1983 * and let new people in. By holding the tree_log_mutex
1984 * from now until after the super is written, we avoid races
1985 * with the tree-log code.
1987 mutex_lock(&root
->fs_info
->tree_log_mutex
);
1989 ret
= commit_fs_roots(trans
, root
);
1991 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
1992 mutex_unlock(&root
->fs_info
->reloc_mutex
);
1993 goto scrub_continue
;
1997 * Since the transaction is done, we can apply the pending changes
1998 * before the next transaction.
2000 btrfs_apply_pending_changes(root
->fs_info
);
2002 /* commit_fs_roots gets rid of all the tree log roots, it is now
2003 * safe to free the root of tree log roots
2005 btrfs_free_log_root_tree(trans
, root
->fs_info
);
2007 ret
= commit_cowonly_roots(trans
, root
);
2009 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2010 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2011 goto scrub_continue
;
2015 * The tasks which save the space cache and inode cache may also
2016 * update ->aborted, check it.
2018 if (unlikely(ACCESS_ONCE(cur_trans
->aborted
))) {
2019 ret
= cur_trans
->aborted
;
2020 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2021 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2022 goto scrub_continue
;
2025 btrfs_prepare_extent_commit(trans
, root
);
2027 cur_trans
= root
->fs_info
->running_transaction
;
2029 btrfs_set_root_node(&root
->fs_info
->tree_root
->root_item
,
2030 root
->fs_info
->tree_root
->node
);
2031 list_add_tail(&root
->fs_info
->tree_root
->dirty_list
,
2032 &cur_trans
->switch_commits
);
2034 btrfs_set_root_node(&root
->fs_info
->chunk_root
->root_item
,
2035 root
->fs_info
->chunk_root
->node
);
2036 list_add_tail(&root
->fs_info
->chunk_root
->dirty_list
,
2037 &cur_trans
->switch_commits
);
2039 switch_commit_roots(cur_trans
, root
->fs_info
);
2041 assert_qgroups_uptodate(trans
);
2042 ASSERT(list_empty(&cur_trans
->dirty_bgs
));
2043 ASSERT(list_empty(&cur_trans
->io_bgs
));
2044 update_super_roots(root
);
2046 btrfs_set_super_log_root(root
->fs_info
->super_copy
, 0);
2047 btrfs_set_super_log_root_level(root
->fs_info
->super_copy
, 0);
2048 memcpy(root
->fs_info
->super_for_commit
, root
->fs_info
->super_copy
,
2049 sizeof(*root
->fs_info
->super_copy
));
2051 btrfs_update_commit_device_size(root
->fs_info
);
2052 btrfs_update_commit_device_bytes_used(root
, cur_trans
);
2054 clear_bit(BTRFS_INODE_BTREE_LOG1_ERR
, &btree_ino
->runtime_flags
);
2055 clear_bit(BTRFS_INODE_BTREE_LOG2_ERR
, &btree_ino
->runtime_flags
);
2057 spin_lock(&root
->fs_info
->trans_lock
);
2058 cur_trans
->state
= TRANS_STATE_UNBLOCKED
;
2059 root
->fs_info
->running_transaction
= NULL
;
2060 spin_unlock(&root
->fs_info
->trans_lock
);
2061 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2063 wake_up(&root
->fs_info
->transaction_wait
);
2065 ret
= btrfs_write_and_wait_transaction(trans
, root
);
2067 btrfs_error(root
->fs_info
, ret
,
2068 "Error while writing out transaction");
2069 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2070 goto scrub_continue
;
2073 ret
= write_ctree_super(trans
, root
, 0);
2075 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2076 goto scrub_continue
;
2080 * the super is written, we can safely allow the tree-loggers
2081 * to go about their business
2083 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2085 btrfs_finish_extent_commit(trans
, root
);
2087 if (cur_trans
->have_free_bgs
)
2088 btrfs_clear_space_info_full(root
->fs_info
);
2090 root
->fs_info
->last_trans_committed
= cur_trans
->transid
;
2092 * We needn't acquire the lock here because there is no other task
2093 * which can change it.
2095 cur_trans
->state
= TRANS_STATE_COMPLETED
;
2096 wake_up(&cur_trans
->commit_wait
);
2098 spin_lock(&root
->fs_info
->trans_lock
);
2099 list_del_init(&cur_trans
->list
);
2100 spin_unlock(&root
->fs_info
->trans_lock
);
2102 btrfs_put_transaction(cur_trans
);
2103 btrfs_put_transaction(cur_trans
);
2105 if (trans
->type
& __TRANS_FREEZABLE
)
2106 sb_end_intwrite(root
->fs_info
->sb
);
2108 trace_btrfs_transaction_commit(root
);
2110 btrfs_scrub_continue(root
);
2112 if (current
->journal_info
== trans
)
2113 current
->journal_info
= NULL
;
2115 kmem_cache_free(btrfs_trans_handle_cachep
, trans
);
2117 if (current
!= root
->fs_info
->transaction_kthread
)
2118 btrfs_run_delayed_iputs(root
);
2123 btrfs_scrub_continue(root
);
2124 cleanup_transaction
:
2125 btrfs_trans_release_metadata(trans
, root
);
2126 trans
->block_rsv
= NULL
;
2127 if (trans
->qgroup_reserved
) {
2128 btrfs_qgroup_free(root
, trans
->qgroup_reserved
);
2129 trans
->qgroup_reserved
= 0;
2131 btrfs_warn(root
->fs_info
, "Skipping commit of aborted transaction.");
2132 if (current
->journal_info
== trans
)
2133 current
->journal_info
= NULL
;
2134 cleanup_transaction(trans
, root
, ret
);
2140 * return < 0 if error
2141 * 0 if there are no more dead_roots at the time of call
2142 * 1 there are more to be processed, call me again
2144 * The return value indicates there are certainly more snapshots to delete, but
2145 * if there comes a new one during processing, it may return 0. We don't mind,
2146 * because btrfs_commit_super will poke cleaner thread and it will process it a
2147 * few seconds later.
2149 int btrfs_clean_one_deleted_snapshot(struct btrfs_root
*root
)
2152 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2154 spin_lock(&fs_info
->trans_lock
);
2155 if (list_empty(&fs_info
->dead_roots
)) {
2156 spin_unlock(&fs_info
->trans_lock
);
2159 root
= list_first_entry(&fs_info
->dead_roots
,
2160 struct btrfs_root
, root_list
);
2161 list_del_init(&root
->root_list
);
2162 spin_unlock(&fs_info
->trans_lock
);
2164 pr_debug("BTRFS: cleaner removing %llu\n", root
->objectid
);
2166 btrfs_kill_all_delayed_nodes(root
);
2168 if (btrfs_header_backref_rev(root
->node
) <
2169 BTRFS_MIXED_BACKREF_REV
)
2170 ret
= btrfs_drop_snapshot(root
, NULL
, 0, 0);
2172 ret
= btrfs_drop_snapshot(root
, NULL
, 1, 0);
2174 return (ret
< 0) ? 0 : 1;
2177 void btrfs_apply_pending_changes(struct btrfs_fs_info
*fs_info
)
2182 prev
= xchg(&fs_info
->pending_changes
, 0);
2186 bit
= 1 << BTRFS_PENDING_SET_INODE_MAP_CACHE
;
2188 btrfs_set_opt(fs_info
->mount_opt
, INODE_MAP_CACHE
);
2191 bit
= 1 << BTRFS_PENDING_CLEAR_INODE_MAP_CACHE
;
2193 btrfs_clear_opt(fs_info
->mount_opt
, INODE_MAP_CACHE
);
2196 bit
= 1 << BTRFS_PENDING_COMMIT
;
2198 btrfs_debug(fs_info
, "pending commit done");
2203 "unknown pending changes left 0x%lx, ignoring", prev
);