1 // SPDX-License-Identifier: GPL-2.0
5 #include "block-group.h"
6 #include "space-info.h"
8 #include "free-space-cache.h"
9 #include "free-space-tree.h"
12 #include "transaction.h"
13 #include "ref-verify.h"
16 #include "delalloc-space.h"
21 * Return target flags in extended format or 0 if restripe for this chunk_type
24 * Should be called with balance_lock held
26 static u64
get_restripe_target(struct btrfs_fs_info
*fs_info
, u64 flags
)
28 struct btrfs_balance_control
*bctl
= fs_info
->balance_ctl
;
34 if (flags
& BTRFS_BLOCK_GROUP_DATA
&&
35 bctl
->data
.flags
& BTRFS_BALANCE_ARGS_CONVERT
) {
36 target
= BTRFS_BLOCK_GROUP_DATA
| bctl
->data
.target
;
37 } else if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
&&
38 bctl
->sys
.flags
& BTRFS_BALANCE_ARGS_CONVERT
) {
39 target
= BTRFS_BLOCK_GROUP_SYSTEM
| bctl
->sys
.target
;
40 } else if (flags
& BTRFS_BLOCK_GROUP_METADATA
&&
41 bctl
->meta
.flags
& BTRFS_BALANCE_ARGS_CONVERT
) {
42 target
= BTRFS_BLOCK_GROUP_METADATA
| bctl
->meta
.target
;
49 * @flags: available profiles in extended format (see ctree.h)
51 * Return reduced profile in chunk format. If profile changing is in progress
52 * (either running or paused) picks the target profile (if it's already
53 * available), otherwise falls back to plain reducing.
55 static u64
btrfs_reduce_alloc_profile(struct btrfs_fs_info
*fs_info
, u64 flags
)
57 u64 num_devices
= fs_info
->fs_devices
->rw_devices
;
63 * See if restripe for this chunk_type is in progress, if so try to
64 * reduce to the target profile
66 spin_lock(&fs_info
->balance_lock
);
67 target
= get_restripe_target(fs_info
, flags
);
69 /* Pick target profile only if it's already available */
70 if ((flags
& target
) & BTRFS_EXTENDED_PROFILE_MASK
) {
71 spin_unlock(&fs_info
->balance_lock
);
72 return extended_to_chunk(target
);
75 spin_unlock(&fs_info
->balance_lock
);
77 /* First, mask out the RAID levels which aren't possible */
78 for (raid_type
= 0; raid_type
< BTRFS_NR_RAID_TYPES
; raid_type
++) {
79 if (num_devices
>= btrfs_raid_array
[raid_type
].devs_min
)
80 allowed
|= btrfs_raid_array
[raid_type
].bg_flag
;
84 if (allowed
& BTRFS_BLOCK_GROUP_RAID6
)
85 allowed
= BTRFS_BLOCK_GROUP_RAID6
;
86 else if (allowed
& BTRFS_BLOCK_GROUP_RAID5
)
87 allowed
= BTRFS_BLOCK_GROUP_RAID5
;
88 else if (allowed
& BTRFS_BLOCK_GROUP_RAID10
)
89 allowed
= BTRFS_BLOCK_GROUP_RAID10
;
90 else if (allowed
& BTRFS_BLOCK_GROUP_RAID1
)
91 allowed
= BTRFS_BLOCK_GROUP_RAID1
;
92 else if (allowed
& BTRFS_BLOCK_GROUP_RAID0
)
93 allowed
= BTRFS_BLOCK_GROUP_RAID0
;
95 flags
&= ~BTRFS_BLOCK_GROUP_PROFILE_MASK
;
97 return extended_to_chunk(flags
| allowed
);
100 u64
btrfs_get_alloc_profile(struct btrfs_fs_info
*fs_info
, u64 orig_flags
)
107 seq
= read_seqbegin(&fs_info
->profiles_lock
);
109 if (flags
& BTRFS_BLOCK_GROUP_DATA
)
110 flags
|= fs_info
->avail_data_alloc_bits
;
111 else if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
)
112 flags
|= fs_info
->avail_system_alloc_bits
;
113 else if (flags
& BTRFS_BLOCK_GROUP_METADATA
)
114 flags
|= fs_info
->avail_metadata_alloc_bits
;
115 } while (read_seqretry(&fs_info
->profiles_lock
, seq
));
117 return btrfs_reduce_alloc_profile(fs_info
, flags
);
120 void btrfs_get_block_group(struct btrfs_block_group
*cache
)
122 atomic_inc(&cache
->count
);
125 void btrfs_put_block_group(struct btrfs_block_group
*cache
)
127 if (atomic_dec_and_test(&cache
->count
)) {
128 WARN_ON(cache
->pinned
> 0);
129 WARN_ON(cache
->reserved
> 0);
132 * A block_group shouldn't be on the discard_list anymore.
133 * Remove the block_group from the discard_list to prevent us
134 * from causing a panic due to NULL pointer dereference.
136 if (WARN_ON(!list_empty(&cache
->discard_list
)))
137 btrfs_discard_cancel_work(&cache
->fs_info
->discard_ctl
,
141 * If not empty, someone is still holding mutex of
142 * full_stripe_lock, which can only be released by caller.
143 * And it will definitely cause use-after-free when caller
144 * tries to release full stripe lock.
146 * No better way to resolve, but only to warn.
148 WARN_ON(!RB_EMPTY_ROOT(&cache
->full_stripe_locks_root
.root
));
149 kfree(cache
->free_space_ctl
);
155 * This adds the block group to the fs_info rb tree for the block group cache
157 static int btrfs_add_block_group_cache(struct btrfs_fs_info
*info
,
158 struct btrfs_block_group
*block_group
)
161 struct rb_node
*parent
= NULL
;
162 struct btrfs_block_group
*cache
;
164 spin_lock(&info
->block_group_cache_lock
);
165 p
= &info
->block_group_cache_tree
.rb_node
;
169 cache
= rb_entry(parent
, struct btrfs_block_group
, cache_node
);
170 if (block_group
->start
< cache
->start
) {
172 } else if (block_group
->start
> cache
->start
) {
175 spin_unlock(&info
->block_group_cache_lock
);
180 rb_link_node(&block_group
->cache_node
, parent
, p
);
181 rb_insert_color(&block_group
->cache_node
,
182 &info
->block_group_cache_tree
);
184 if (info
->first_logical_byte
> block_group
->start
)
185 info
->first_logical_byte
= block_group
->start
;
187 spin_unlock(&info
->block_group_cache_lock
);
193 * This will return the block group at or after bytenr if contains is 0, else
194 * it will return the block group that contains the bytenr
196 static struct btrfs_block_group
*block_group_cache_tree_search(
197 struct btrfs_fs_info
*info
, u64 bytenr
, int contains
)
199 struct btrfs_block_group
*cache
, *ret
= NULL
;
203 spin_lock(&info
->block_group_cache_lock
);
204 n
= info
->block_group_cache_tree
.rb_node
;
207 cache
= rb_entry(n
, struct btrfs_block_group
, cache_node
);
208 end
= cache
->start
+ cache
->length
- 1;
209 start
= cache
->start
;
211 if (bytenr
< start
) {
212 if (!contains
&& (!ret
|| start
< ret
->start
))
215 } else if (bytenr
> start
) {
216 if (contains
&& bytenr
<= end
) {
227 btrfs_get_block_group(ret
);
228 if (bytenr
== 0 && info
->first_logical_byte
> ret
->start
)
229 info
->first_logical_byte
= ret
->start
;
231 spin_unlock(&info
->block_group_cache_lock
);
237 * Return the block group that starts at or after bytenr
239 struct btrfs_block_group
*btrfs_lookup_first_block_group(
240 struct btrfs_fs_info
*info
, u64 bytenr
)
242 return block_group_cache_tree_search(info
, bytenr
, 0);
246 * Return the block group that contains the given bytenr
248 struct btrfs_block_group
*btrfs_lookup_block_group(
249 struct btrfs_fs_info
*info
, u64 bytenr
)
251 return block_group_cache_tree_search(info
, bytenr
, 1);
254 struct btrfs_block_group
*btrfs_next_block_group(
255 struct btrfs_block_group
*cache
)
257 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
258 struct rb_node
*node
;
260 spin_lock(&fs_info
->block_group_cache_lock
);
262 /* If our block group was removed, we need a full search. */
263 if (RB_EMPTY_NODE(&cache
->cache_node
)) {
264 const u64 next_bytenr
= cache
->start
+ cache
->length
;
266 spin_unlock(&fs_info
->block_group_cache_lock
);
267 btrfs_put_block_group(cache
);
268 cache
= btrfs_lookup_first_block_group(fs_info
, next_bytenr
); return cache
;
270 node
= rb_next(&cache
->cache_node
);
271 btrfs_put_block_group(cache
);
273 cache
= rb_entry(node
, struct btrfs_block_group
, cache_node
);
274 btrfs_get_block_group(cache
);
277 spin_unlock(&fs_info
->block_group_cache_lock
);
281 bool btrfs_inc_nocow_writers(struct btrfs_fs_info
*fs_info
, u64 bytenr
)
283 struct btrfs_block_group
*bg
;
286 bg
= btrfs_lookup_block_group(fs_info
, bytenr
);
290 spin_lock(&bg
->lock
);
294 atomic_inc(&bg
->nocow_writers
);
295 spin_unlock(&bg
->lock
);
297 /* No put on block group, done by btrfs_dec_nocow_writers */
299 btrfs_put_block_group(bg
);
304 void btrfs_dec_nocow_writers(struct btrfs_fs_info
*fs_info
, u64 bytenr
)
306 struct btrfs_block_group
*bg
;
308 bg
= btrfs_lookup_block_group(fs_info
, bytenr
);
310 if (atomic_dec_and_test(&bg
->nocow_writers
))
311 wake_up_var(&bg
->nocow_writers
);
313 * Once for our lookup and once for the lookup done by a previous call
314 * to btrfs_inc_nocow_writers()
316 btrfs_put_block_group(bg
);
317 btrfs_put_block_group(bg
);
320 void btrfs_wait_nocow_writers(struct btrfs_block_group
*bg
)
322 wait_var_event(&bg
->nocow_writers
, !atomic_read(&bg
->nocow_writers
));
325 void btrfs_dec_block_group_reservations(struct btrfs_fs_info
*fs_info
,
328 struct btrfs_block_group
*bg
;
330 bg
= btrfs_lookup_block_group(fs_info
, start
);
332 if (atomic_dec_and_test(&bg
->reservations
))
333 wake_up_var(&bg
->reservations
);
334 btrfs_put_block_group(bg
);
337 void btrfs_wait_block_group_reservations(struct btrfs_block_group
*bg
)
339 struct btrfs_space_info
*space_info
= bg
->space_info
;
343 if (!(bg
->flags
& BTRFS_BLOCK_GROUP_DATA
))
347 * Our block group is read only but before we set it to read only,
348 * some task might have had allocated an extent from it already, but it
349 * has not yet created a respective ordered extent (and added it to a
350 * root's list of ordered extents).
351 * Therefore wait for any task currently allocating extents, since the
352 * block group's reservations counter is incremented while a read lock
353 * on the groups' semaphore is held and decremented after releasing
354 * the read access on that semaphore and creating the ordered extent.
356 down_write(&space_info
->groups_sem
);
357 up_write(&space_info
->groups_sem
);
359 wait_var_event(&bg
->reservations
, !atomic_read(&bg
->reservations
));
362 struct btrfs_caching_control
*btrfs_get_caching_control(
363 struct btrfs_block_group
*cache
)
365 struct btrfs_caching_control
*ctl
;
367 spin_lock(&cache
->lock
);
368 if (!cache
->caching_ctl
) {
369 spin_unlock(&cache
->lock
);
373 ctl
= cache
->caching_ctl
;
374 refcount_inc(&ctl
->count
);
375 spin_unlock(&cache
->lock
);
379 void btrfs_put_caching_control(struct btrfs_caching_control
*ctl
)
381 if (refcount_dec_and_test(&ctl
->count
))
386 * When we wait for progress in the block group caching, its because our
387 * allocation attempt failed at least once. So, we must sleep and let some
388 * progress happen before we try again.
390 * This function will sleep at least once waiting for new free space to show
391 * up, and then it will check the block group free space numbers for our min
392 * num_bytes. Another option is to have it go ahead and look in the rbtree for
393 * a free extent of a given size, but this is a good start.
395 * Callers of this must check if cache->cached == BTRFS_CACHE_ERROR before using
396 * any of the information in this block group.
398 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group
*cache
,
401 struct btrfs_caching_control
*caching_ctl
;
403 caching_ctl
= btrfs_get_caching_control(cache
);
407 wait_event(caching_ctl
->wait
, btrfs_block_group_done(cache
) ||
408 (cache
->free_space_ctl
->free_space
>= num_bytes
));
410 btrfs_put_caching_control(caching_ctl
);
413 int btrfs_wait_block_group_cache_done(struct btrfs_block_group
*cache
)
415 struct btrfs_caching_control
*caching_ctl
;
418 caching_ctl
= btrfs_get_caching_control(cache
);
420 return (cache
->cached
== BTRFS_CACHE_ERROR
) ? -EIO
: 0;
422 wait_event(caching_ctl
->wait
, btrfs_block_group_done(cache
));
423 if (cache
->cached
== BTRFS_CACHE_ERROR
)
425 btrfs_put_caching_control(caching_ctl
);
429 #ifdef CONFIG_BTRFS_DEBUG
430 static void fragment_free_space(struct btrfs_block_group
*block_group
)
432 struct btrfs_fs_info
*fs_info
= block_group
->fs_info
;
433 u64 start
= block_group
->start
;
434 u64 len
= block_group
->length
;
435 u64 chunk
= block_group
->flags
& BTRFS_BLOCK_GROUP_METADATA
?
436 fs_info
->nodesize
: fs_info
->sectorsize
;
437 u64 step
= chunk
<< 1;
439 while (len
> chunk
) {
440 btrfs_remove_free_space(block_group
, start
, chunk
);
451 * This is only called by btrfs_cache_block_group, since we could have freed
452 * extents we need to check the pinned_extents for any extents that can't be
453 * used yet since their free space will be released as soon as the transaction
456 u64
add_new_free_space(struct btrfs_block_group
*block_group
, u64 start
, u64 end
)
458 struct btrfs_fs_info
*info
= block_group
->fs_info
;
459 u64 extent_start
, extent_end
, size
, total_added
= 0;
462 while (start
< end
) {
463 ret
= find_first_extent_bit(&info
->excluded_extents
, start
,
464 &extent_start
, &extent_end
,
465 EXTENT_DIRTY
| EXTENT_UPTODATE
,
470 if (extent_start
<= start
) {
471 start
= extent_end
+ 1;
472 } else if (extent_start
> start
&& extent_start
< end
) {
473 size
= extent_start
- start
;
475 ret
= btrfs_add_free_space_async_trimmed(block_group
,
477 BUG_ON(ret
); /* -ENOMEM or logic error */
478 start
= extent_end
+ 1;
487 ret
= btrfs_add_free_space_async_trimmed(block_group
, start
,
489 BUG_ON(ret
); /* -ENOMEM or logic error */
495 static int load_extent_tree_free(struct btrfs_caching_control
*caching_ctl
)
497 struct btrfs_block_group
*block_group
= caching_ctl
->block_group
;
498 struct btrfs_fs_info
*fs_info
= block_group
->fs_info
;
499 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
500 struct btrfs_path
*path
;
501 struct extent_buffer
*leaf
;
502 struct btrfs_key key
;
509 path
= btrfs_alloc_path();
513 last
= max_t(u64
, block_group
->start
, BTRFS_SUPER_INFO_OFFSET
);
515 #ifdef CONFIG_BTRFS_DEBUG
517 * If we're fragmenting we don't want to make anybody think we can
518 * allocate from this block group until we've had a chance to fragment
521 if (btrfs_should_fragment_free_space(block_group
))
525 * We don't want to deadlock with somebody trying to allocate a new
526 * extent for the extent root while also trying to search the extent
527 * root to add free space. So we skip locking and search the commit
528 * root, since its read-only
530 path
->skip_locking
= 1;
531 path
->search_commit_root
= 1;
532 path
->reada
= READA_FORWARD
;
536 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
539 ret
= btrfs_search_slot(NULL
, extent_root
, &key
, path
, 0, 0);
543 leaf
= path
->nodes
[0];
544 nritems
= btrfs_header_nritems(leaf
);
547 if (btrfs_fs_closing(fs_info
) > 1) {
552 if (path
->slots
[0] < nritems
) {
553 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
555 ret
= btrfs_find_next_key(extent_root
, path
, &key
, 0, 0);
559 if (need_resched() ||
560 rwsem_is_contended(&fs_info
->commit_root_sem
)) {
562 caching_ctl
->progress
= last
;
563 btrfs_release_path(path
);
564 up_read(&fs_info
->commit_root_sem
);
565 mutex_unlock(&caching_ctl
->mutex
);
567 mutex_lock(&caching_ctl
->mutex
);
568 down_read(&fs_info
->commit_root_sem
);
572 ret
= btrfs_next_leaf(extent_root
, path
);
577 leaf
= path
->nodes
[0];
578 nritems
= btrfs_header_nritems(leaf
);
582 if (key
.objectid
< last
) {
585 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
588 caching_ctl
->progress
= last
;
589 btrfs_release_path(path
);
593 if (key
.objectid
< block_group
->start
) {
598 if (key
.objectid
>= block_group
->start
+ block_group
->length
)
601 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
||
602 key
.type
== BTRFS_METADATA_ITEM_KEY
) {
603 total_found
+= add_new_free_space(block_group
, last
,
605 if (key
.type
== BTRFS_METADATA_ITEM_KEY
)
606 last
= key
.objectid
+
609 last
= key
.objectid
+ key
.offset
;
611 if (total_found
> CACHING_CTL_WAKE_UP
) {
614 wake_up(&caching_ctl
->wait
);
621 total_found
+= add_new_free_space(block_group
, last
,
622 block_group
->start
+ block_group
->length
);
623 caching_ctl
->progress
= (u64
)-1;
626 btrfs_free_path(path
);
630 static noinline
void caching_thread(struct btrfs_work
*work
)
632 struct btrfs_block_group
*block_group
;
633 struct btrfs_fs_info
*fs_info
;
634 struct btrfs_caching_control
*caching_ctl
;
637 caching_ctl
= container_of(work
, struct btrfs_caching_control
, work
);
638 block_group
= caching_ctl
->block_group
;
639 fs_info
= block_group
->fs_info
;
641 mutex_lock(&caching_ctl
->mutex
);
642 down_read(&fs_info
->commit_root_sem
);
644 if (btrfs_fs_compat_ro(fs_info
, FREE_SPACE_TREE
))
645 ret
= load_free_space_tree(caching_ctl
);
647 ret
= load_extent_tree_free(caching_ctl
);
649 spin_lock(&block_group
->lock
);
650 block_group
->caching_ctl
= NULL
;
651 block_group
->cached
= ret
? BTRFS_CACHE_ERROR
: BTRFS_CACHE_FINISHED
;
652 spin_unlock(&block_group
->lock
);
654 #ifdef CONFIG_BTRFS_DEBUG
655 if (btrfs_should_fragment_free_space(block_group
)) {
658 spin_lock(&block_group
->space_info
->lock
);
659 spin_lock(&block_group
->lock
);
660 bytes_used
= block_group
->length
- block_group
->used
;
661 block_group
->space_info
->bytes_used
+= bytes_used
>> 1;
662 spin_unlock(&block_group
->lock
);
663 spin_unlock(&block_group
->space_info
->lock
);
664 fragment_free_space(block_group
);
668 caching_ctl
->progress
= (u64
)-1;
670 up_read(&fs_info
->commit_root_sem
);
671 btrfs_free_excluded_extents(block_group
);
672 mutex_unlock(&caching_ctl
->mutex
);
674 wake_up(&caching_ctl
->wait
);
676 btrfs_put_caching_control(caching_ctl
);
677 btrfs_put_block_group(block_group
);
680 int btrfs_cache_block_group(struct btrfs_block_group
*cache
, int load_cache_only
)
683 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
684 struct btrfs_caching_control
*caching_ctl
;
687 caching_ctl
= kzalloc(sizeof(*caching_ctl
), GFP_NOFS
);
691 INIT_LIST_HEAD(&caching_ctl
->list
);
692 mutex_init(&caching_ctl
->mutex
);
693 init_waitqueue_head(&caching_ctl
->wait
);
694 caching_ctl
->block_group
= cache
;
695 caching_ctl
->progress
= cache
->start
;
696 refcount_set(&caching_ctl
->count
, 1);
697 btrfs_init_work(&caching_ctl
->work
, caching_thread
, NULL
, NULL
);
699 spin_lock(&cache
->lock
);
701 * This should be a rare occasion, but this could happen I think in the
702 * case where one thread starts to load the space cache info, and then
703 * some other thread starts a transaction commit which tries to do an
704 * allocation while the other thread is still loading the space cache
705 * info. The previous loop should have kept us from choosing this block
706 * group, but if we've moved to the state where we will wait on caching
707 * block groups we need to first check if we're doing a fast load here,
708 * so we can wait for it to finish, otherwise we could end up allocating
709 * from a block group who's cache gets evicted for one reason or
712 while (cache
->cached
== BTRFS_CACHE_FAST
) {
713 struct btrfs_caching_control
*ctl
;
715 ctl
= cache
->caching_ctl
;
716 refcount_inc(&ctl
->count
);
717 prepare_to_wait(&ctl
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
718 spin_unlock(&cache
->lock
);
722 finish_wait(&ctl
->wait
, &wait
);
723 btrfs_put_caching_control(ctl
);
724 spin_lock(&cache
->lock
);
727 if (cache
->cached
!= BTRFS_CACHE_NO
) {
728 spin_unlock(&cache
->lock
);
732 WARN_ON(cache
->caching_ctl
);
733 cache
->caching_ctl
= caching_ctl
;
734 cache
->cached
= BTRFS_CACHE_FAST
;
735 spin_unlock(&cache
->lock
);
737 if (btrfs_test_opt(fs_info
, SPACE_CACHE
)) {
738 mutex_lock(&caching_ctl
->mutex
);
739 ret
= load_free_space_cache(cache
);
741 spin_lock(&cache
->lock
);
743 cache
->caching_ctl
= NULL
;
744 cache
->cached
= BTRFS_CACHE_FINISHED
;
745 cache
->last_byte_to_unpin
= (u64
)-1;
746 caching_ctl
->progress
= (u64
)-1;
748 if (load_cache_only
) {
749 cache
->caching_ctl
= NULL
;
750 cache
->cached
= BTRFS_CACHE_NO
;
752 cache
->cached
= BTRFS_CACHE_STARTED
;
753 cache
->has_caching_ctl
= 1;
756 spin_unlock(&cache
->lock
);
757 #ifdef CONFIG_BTRFS_DEBUG
759 btrfs_should_fragment_free_space(cache
)) {
762 spin_lock(&cache
->space_info
->lock
);
763 spin_lock(&cache
->lock
);
764 bytes_used
= cache
->length
- cache
->used
;
765 cache
->space_info
->bytes_used
+= bytes_used
>> 1;
766 spin_unlock(&cache
->lock
);
767 spin_unlock(&cache
->space_info
->lock
);
768 fragment_free_space(cache
);
771 mutex_unlock(&caching_ctl
->mutex
);
773 wake_up(&caching_ctl
->wait
);
775 btrfs_put_caching_control(caching_ctl
);
776 btrfs_free_excluded_extents(cache
);
781 * We're either using the free space tree or no caching at all.
782 * Set cached to the appropriate value and wakeup any waiters.
784 spin_lock(&cache
->lock
);
785 if (load_cache_only
) {
786 cache
->caching_ctl
= NULL
;
787 cache
->cached
= BTRFS_CACHE_NO
;
789 cache
->cached
= BTRFS_CACHE_STARTED
;
790 cache
->has_caching_ctl
= 1;
792 spin_unlock(&cache
->lock
);
793 wake_up(&caching_ctl
->wait
);
796 if (load_cache_only
) {
797 btrfs_put_caching_control(caching_ctl
);
801 down_write(&fs_info
->commit_root_sem
);
802 refcount_inc(&caching_ctl
->count
);
803 list_add_tail(&caching_ctl
->list
, &fs_info
->caching_block_groups
);
804 up_write(&fs_info
->commit_root_sem
);
806 btrfs_get_block_group(cache
);
808 btrfs_queue_work(fs_info
->caching_workers
, &caching_ctl
->work
);
813 static void clear_avail_alloc_bits(struct btrfs_fs_info
*fs_info
, u64 flags
)
815 u64 extra_flags
= chunk_to_extended(flags
) &
816 BTRFS_EXTENDED_PROFILE_MASK
;
818 write_seqlock(&fs_info
->profiles_lock
);
819 if (flags
& BTRFS_BLOCK_GROUP_DATA
)
820 fs_info
->avail_data_alloc_bits
&= ~extra_flags
;
821 if (flags
& BTRFS_BLOCK_GROUP_METADATA
)
822 fs_info
->avail_metadata_alloc_bits
&= ~extra_flags
;
823 if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
)
824 fs_info
->avail_system_alloc_bits
&= ~extra_flags
;
825 write_sequnlock(&fs_info
->profiles_lock
);
829 * Clear incompat bits for the following feature(s):
831 * - RAID56 - in case there's neither RAID5 nor RAID6 profile block group
832 * in the whole filesystem
834 * - RAID1C34 - same as above for RAID1C3 and RAID1C4 block groups
836 static void clear_incompat_bg_bits(struct btrfs_fs_info
*fs_info
, u64 flags
)
838 bool found_raid56
= false;
839 bool found_raid1c34
= false;
841 if ((flags
& BTRFS_BLOCK_GROUP_RAID56_MASK
) ||
842 (flags
& BTRFS_BLOCK_GROUP_RAID1C3
) ||
843 (flags
& BTRFS_BLOCK_GROUP_RAID1C4
)) {
844 struct list_head
*head
= &fs_info
->space_info
;
845 struct btrfs_space_info
*sinfo
;
847 list_for_each_entry_rcu(sinfo
, head
, list
) {
848 down_read(&sinfo
->groups_sem
);
849 if (!list_empty(&sinfo
->block_groups
[BTRFS_RAID_RAID5
]))
851 if (!list_empty(&sinfo
->block_groups
[BTRFS_RAID_RAID6
]))
853 if (!list_empty(&sinfo
->block_groups
[BTRFS_RAID_RAID1C3
]))
854 found_raid1c34
= true;
855 if (!list_empty(&sinfo
->block_groups
[BTRFS_RAID_RAID1C4
]))
856 found_raid1c34
= true;
857 up_read(&sinfo
->groups_sem
);
860 btrfs_clear_fs_incompat(fs_info
, RAID56
);
862 btrfs_clear_fs_incompat(fs_info
, RAID1C34
);
866 int btrfs_remove_block_group(struct btrfs_trans_handle
*trans
,
867 u64 group_start
, struct extent_map
*em
)
869 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
870 struct btrfs_root
*root
= fs_info
->extent_root
;
871 struct btrfs_path
*path
;
872 struct btrfs_block_group
*block_group
;
873 struct btrfs_free_cluster
*cluster
;
874 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
875 struct btrfs_key key
;
877 struct kobject
*kobj
= NULL
;
881 struct btrfs_caching_control
*caching_ctl
= NULL
;
883 bool remove_rsv
= false;
885 block_group
= btrfs_lookup_block_group(fs_info
, group_start
);
886 BUG_ON(!block_group
);
887 BUG_ON(!block_group
->ro
);
889 trace_btrfs_remove_block_group(block_group
);
891 * Free the reserved super bytes from this block group before
894 btrfs_free_excluded_extents(block_group
);
895 btrfs_free_ref_tree_range(fs_info
, block_group
->start
,
896 block_group
->length
);
898 index
= btrfs_bg_flags_to_raid_index(block_group
->flags
);
899 factor
= btrfs_bg_type_to_factor(block_group
->flags
);
901 /* make sure this block group isn't part of an allocation cluster */
902 cluster
= &fs_info
->data_alloc_cluster
;
903 spin_lock(&cluster
->refill_lock
);
904 btrfs_return_cluster_to_free_space(block_group
, cluster
);
905 spin_unlock(&cluster
->refill_lock
);
908 * make sure this block group isn't part of a metadata
911 cluster
= &fs_info
->meta_alloc_cluster
;
912 spin_lock(&cluster
->refill_lock
);
913 btrfs_return_cluster_to_free_space(block_group
, cluster
);
914 spin_unlock(&cluster
->refill_lock
);
916 path
= btrfs_alloc_path();
923 * get the inode first so any iput calls done for the io_list
924 * aren't the final iput (no unlinks allowed now)
926 inode
= lookup_free_space_inode(block_group
, path
);
928 mutex_lock(&trans
->transaction
->cache_write_mutex
);
930 * Make sure our free space cache IO is done before removing the
933 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
934 if (!list_empty(&block_group
->io_list
)) {
935 list_del_init(&block_group
->io_list
);
937 WARN_ON(!IS_ERR(inode
) && inode
!= block_group
->io_ctl
.inode
);
939 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
940 btrfs_wait_cache_io(trans
, block_group
, path
);
941 btrfs_put_block_group(block_group
);
942 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
945 if (!list_empty(&block_group
->dirty_list
)) {
946 list_del_init(&block_group
->dirty_list
);
948 btrfs_put_block_group(block_group
);
950 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
951 mutex_unlock(&trans
->transaction
->cache_write_mutex
);
953 if (!IS_ERR(inode
)) {
954 ret
= btrfs_orphan_add(trans
, BTRFS_I(inode
));
956 btrfs_add_delayed_iput(inode
);
960 /* One for the block groups ref */
961 spin_lock(&block_group
->lock
);
962 if (block_group
->iref
) {
963 block_group
->iref
= 0;
964 block_group
->inode
= NULL
;
965 spin_unlock(&block_group
->lock
);
968 spin_unlock(&block_group
->lock
);
970 /* One for our lookup ref */
971 btrfs_add_delayed_iput(inode
);
974 key
.objectid
= BTRFS_FREE_SPACE_OBJECTID
;
976 key
.offset
= block_group
->start
;
978 ret
= btrfs_search_slot(trans
, tree_root
, &key
, path
, -1, 1);
982 btrfs_release_path(path
);
984 ret
= btrfs_del_item(trans
, tree_root
, path
);
987 btrfs_release_path(path
);
990 spin_lock(&fs_info
->block_group_cache_lock
);
991 rb_erase(&block_group
->cache_node
,
992 &fs_info
->block_group_cache_tree
);
993 RB_CLEAR_NODE(&block_group
->cache_node
);
995 if (fs_info
->first_logical_byte
== block_group
->start
)
996 fs_info
->first_logical_byte
= (u64
)-1;
997 spin_unlock(&fs_info
->block_group_cache_lock
);
999 down_write(&block_group
->space_info
->groups_sem
);
1001 * we must use list_del_init so people can check to see if they
1002 * are still on the list after taking the semaphore
1004 list_del_init(&block_group
->list
);
1005 if (list_empty(&block_group
->space_info
->block_groups
[index
])) {
1006 kobj
= block_group
->space_info
->block_group_kobjs
[index
];
1007 block_group
->space_info
->block_group_kobjs
[index
] = NULL
;
1008 clear_avail_alloc_bits(fs_info
, block_group
->flags
);
1010 up_write(&block_group
->space_info
->groups_sem
);
1011 clear_incompat_bg_bits(fs_info
, block_group
->flags
);
1017 if (block_group
->has_caching_ctl
)
1018 caching_ctl
= btrfs_get_caching_control(block_group
);
1019 if (block_group
->cached
== BTRFS_CACHE_STARTED
)
1020 btrfs_wait_block_group_cache_done(block_group
);
1021 if (block_group
->has_caching_ctl
) {
1022 down_write(&fs_info
->commit_root_sem
);
1024 struct btrfs_caching_control
*ctl
;
1026 list_for_each_entry(ctl
,
1027 &fs_info
->caching_block_groups
, list
)
1028 if (ctl
->block_group
== block_group
) {
1030 refcount_inc(&caching_ctl
->count
);
1035 list_del_init(&caching_ctl
->list
);
1036 up_write(&fs_info
->commit_root_sem
);
1038 /* Once for the caching bgs list and once for us. */
1039 btrfs_put_caching_control(caching_ctl
);
1040 btrfs_put_caching_control(caching_ctl
);
1044 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
1045 WARN_ON(!list_empty(&block_group
->dirty_list
));
1046 WARN_ON(!list_empty(&block_group
->io_list
));
1047 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
1049 btrfs_remove_free_space_cache(block_group
);
1051 spin_lock(&block_group
->space_info
->lock
);
1052 list_del_init(&block_group
->ro_list
);
1054 if (btrfs_test_opt(fs_info
, ENOSPC_DEBUG
)) {
1055 WARN_ON(block_group
->space_info
->total_bytes
1056 < block_group
->length
);
1057 WARN_ON(block_group
->space_info
->bytes_readonly
1058 < block_group
->length
);
1059 WARN_ON(block_group
->space_info
->disk_total
1060 < block_group
->length
* factor
);
1062 block_group
->space_info
->total_bytes
-= block_group
->length
;
1063 block_group
->space_info
->bytes_readonly
-= block_group
->length
;
1064 block_group
->space_info
->disk_total
-= block_group
->length
* factor
;
1066 spin_unlock(&block_group
->space_info
->lock
);
1068 key
.objectid
= block_group
->start
;
1069 key
.type
= BTRFS_BLOCK_GROUP_ITEM_KEY
;
1070 key
.offset
= block_group
->length
;
1072 mutex_lock(&fs_info
->chunk_mutex
);
1073 spin_lock(&block_group
->lock
);
1074 block_group
->removed
= 1;
1076 * At this point trimming can't start on this block group, because we
1077 * removed the block group from the tree fs_info->block_group_cache_tree
1078 * so no one can't find it anymore and even if someone already got this
1079 * block group before we removed it from the rbtree, they have already
1080 * incremented block_group->trimming - if they didn't, they won't find
1081 * any free space entries because we already removed them all when we
1082 * called btrfs_remove_free_space_cache().
1084 * And we must not remove the extent map from the fs_info->mapping_tree
1085 * to prevent the same logical address range and physical device space
1086 * ranges from being reused for a new block group. This is because our
1087 * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is
1088 * completely transactionless, so while it is trimming a range the
1089 * currently running transaction might finish and a new one start,
1090 * allowing for new block groups to be created that can reuse the same
1091 * physical device locations unless we take this special care.
1093 * There may also be an implicit trim operation if the file system
1094 * is mounted with -odiscard. The same protections must remain
1095 * in place until the extents have been discarded completely when
1096 * the transaction commit has completed.
1098 remove_em
= (atomic_read(&block_group
->trimming
) == 0);
1099 spin_unlock(&block_group
->lock
);
1101 mutex_unlock(&fs_info
->chunk_mutex
);
1103 ret
= remove_block_group_free_space(trans
, block_group
);
1107 /* Once for the block groups rbtree */
1108 btrfs_put_block_group(block_group
);
1110 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1116 ret
= btrfs_del_item(trans
, root
, path
);
1121 struct extent_map_tree
*em_tree
;
1123 em_tree
= &fs_info
->mapping_tree
;
1124 write_lock(&em_tree
->lock
);
1125 remove_extent_mapping(em_tree
, em
);
1126 write_unlock(&em_tree
->lock
);
1127 /* once for the tree */
1128 free_extent_map(em
);
1132 /* Once for the lookup reference */
1133 btrfs_put_block_group(block_group
);
1136 btrfs_delayed_refs_rsv_release(fs_info
, 1);
1137 btrfs_free_path(path
);
1141 struct btrfs_trans_handle
*btrfs_start_trans_remove_block_group(
1142 struct btrfs_fs_info
*fs_info
, const u64 chunk_offset
)
1144 struct extent_map_tree
*em_tree
= &fs_info
->mapping_tree
;
1145 struct extent_map
*em
;
1146 struct map_lookup
*map
;
1147 unsigned int num_items
;
1149 read_lock(&em_tree
->lock
);
1150 em
= lookup_extent_mapping(em_tree
, chunk_offset
, 1);
1151 read_unlock(&em_tree
->lock
);
1152 ASSERT(em
&& em
->start
== chunk_offset
);
1155 * We need to reserve 3 + N units from the metadata space info in order
1156 * to remove a block group (done at btrfs_remove_chunk() and at
1157 * btrfs_remove_block_group()), which are used for:
1159 * 1 unit for adding the free space inode's orphan (located in the tree
1161 * 1 unit for deleting the block group item (located in the extent
1163 * 1 unit for deleting the free space item (located in tree of tree
1165 * N units for deleting N device extent items corresponding to each
1166 * stripe (located in the device tree).
1168 * In order to remove a block group we also need to reserve units in the
1169 * system space info in order to update the chunk tree (update one or
1170 * more device items and remove one chunk item), but this is done at
1171 * btrfs_remove_chunk() through a call to check_system_chunk().
1173 map
= em
->map_lookup
;
1174 num_items
= 3 + map
->num_stripes
;
1175 free_extent_map(em
);
1177 return btrfs_start_transaction_fallback_global_rsv(fs_info
->extent_root
,
1182 * Mark block group @cache read-only, so later write won't happen to block
1185 * If @force is not set, this function will only mark the block group readonly
1186 * if we have enough free space (1M) in other metadata/system block groups.
1187 * If @force is not set, this function will mark the block group readonly
1188 * without checking free space.
1190 * NOTE: This function doesn't care if other block groups can contain all the
1191 * data in this block group. That check should be done by relocation routine,
1192 * not this function.
1194 static int inc_block_group_ro(struct btrfs_block_group
*cache
, int force
)
1196 struct btrfs_space_info
*sinfo
= cache
->space_info
;
1200 spin_lock(&sinfo
->lock
);
1201 spin_lock(&cache
->lock
);
1209 num_bytes
= cache
->length
- cache
->reserved
- cache
->pinned
-
1210 cache
->bytes_super
- cache
->used
;
1213 * Data never overcommits, even in mixed mode, so do just the straight
1214 * check of left over space in how much we have allocated.
1218 } else if (sinfo
->flags
& BTRFS_BLOCK_GROUP_DATA
) {
1219 u64 sinfo_used
= btrfs_space_info_used(sinfo
, true);
1222 * Here we make sure if we mark this bg RO, we still have enough
1223 * free space as buffer.
1225 if (sinfo_used
+ num_bytes
<= sinfo
->total_bytes
)
1229 * We overcommit metadata, so we need to do the
1230 * btrfs_can_overcommit check here, and we need to pass in
1231 * BTRFS_RESERVE_NO_FLUSH to give ourselves the most amount of
1232 * leeway to allow us to mark this block group as read only.
1234 if (btrfs_can_overcommit(cache
->fs_info
, sinfo
, num_bytes
,
1235 BTRFS_RESERVE_NO_FLUSH
))
1240 sinfo
->bytes_readonly
+= num_bytes
;
1242 list_add_tail(&cache
->ro_list
, &sinfo
->ro_bgs
);
1245 spin_unlock(&cache
->lock
);
1246 spin_unlock(&sinfo
->lock
);
1247 if (ret
== -ENOSPC
&& btrfs_test_opt(cache
->fs_info
, ENOSPC_DEBUG
)) {
1248 btrfs_info(cache
->fs_info
,
1249 "unable to make block group %llu ro", cache
->start
);
1250 btrfs_dump_space_info(cache
->fs_info
, cache
->space_info
, 0, 0);
1255 static bool clean_pinned_extents(struct btrfs_trans_handle
*trans
,
1256 struct btrfs_block_group
*bg
)
1258 struct btrfs_fs_info
*fs_info
= bg
->fs_info
;
1259 struct btrfs_transaction
*prev_trans
= NULL
;
1260 const u64 start
= bg
->start
;
1261 const u64 end
= start
+ bg
->length
- 1;
1264 spin_lock(&fs_info
->trans_lock
);
1265 if (trans
->transaction
->list
.prev
!= &fs_info
->trans_list
) {
1266 prev_trans
= list_last_entry(&trans
->transaction
->list
,
1267 struct btrfs_transaction
, list
);
1268 refcount_inc(&prev_trans
->use_count
);
1270 spin_unlock(&fs_info
->trans_lock
);
1273 * Hold the unused_bg_unpin_mutex lock to avoid racing with
1274 * btrfs_finish_extent_commit(). If we are at transaction N, another
1275 * task might be running finish_extent_commit() for the previous
1276 * transaction N - 1, and have seen a range belonging to the block
1277 * group in pinned_extents before we were able to clear the whole block
1278 * group range from pinned_extents. This means that task can lookup for
1279 * the block group after we unpinned it from pinned_extents and removed
1280 * it, leading to a BUG_ON() at unpin_extent_range().
1282 mutex_lock(&fs_info
->unused_bg_unpin_mutex
);
1284 ret
= clear_extent_bits(&prev_trans
->pinned_extents
, start
, end
,
1290 ret
= clear_extent_bits(&trans
->transaction
->pinned_extents
, start
, end
,
1294 mutex_unlock(&fs_info
->unused_bg_unpin_mutex
);
1296 btrfs_put_transaction(prev_trans
);
1301 mutex_unlock(&fs_info
->unused_bg_unpin_mutex
);
1303 btrfs_put_transaction(prev_trans
);
1304 btrfs_dec_block_group_ro(bg
);
1309 * Process the unused_bgs list and remove any that don't have any allocated
1310 * space inside of them.
1312 void btrfs_delete_unused_bgs(struct btrfs_fs_info
*fs_info
)
1314 struct btrfs_block_group
*block_group
;
1315 struct btrfs_space_info
*space_info
;
1316 struct btrfs_trans_handle
*trans
;
1317 const bool async_trim_enabled
= btrfs_test_opt(fs_info
, DISCARD_ASYNC
);
1320 if (!test_bit(BTRFS_FS_OPEN
, &fs_info
->flags
))
1323 spin_lock(&fs_info
->unused_bgs_lock
);
1324 while (!list_empty(&fs_info
->unused_bgs
)) {
1327 block_group
= list_first_entry(&fs_info
->unused_bgs
,
1328 struct btrfs_block_group
,
1330 list_del_init(&block_group
->bg_list
);
1332 space_info
= block_group
->space_info
;
1334 if (ret
|| btrfs_mixed_space_info(space_info
)) {
1335 btrfs_put_block_group(block_group
);
1338 spin_unlock(&fs_info
->unused_bgs_lock
);
1340 btrfs_discard_cancel_work(&fs_info
->discard_ctl
, block_group
);
1342 mutex_lock(&fs_info
->delete_unused_bgs_mutex
);
1344 /* Don't want to race with allocators so take the groups_sem */
1345 down_write(&space_info
->groups_sem
);
1348 * Async discard moves the final block group discard to be prior
1349 * to the unused_bgs code path. Therefore, if it's not fully
1350 * trimmed, punt it back to the async discard lists.
1352 if (btrfs_test_opt(fs_info
, DISCARD_ASYNC
) &&
1353 !btrfs_is_free_space_trimmed(block_group
)) {
1354 trace_btrfs_skip_unused_block_group(block_group
);
1355 up_write(&space_info
->groups_sem
);
1356 /* Requeue if we failed because of async discard */
1357 btrfs_discard_queue_work(&fs_info
->discard_ctl
,
1362 spin_lock(&block_group
->lock
);
1363 if (block_group
->reserved
|| block_group
->pinned
||
1364 block_group
->used
|| block_group
->ro
||
1365 list_is_singular(&block_group
->list
)) {
1367 * We want to bail if we made new allocations or have
1368 * outstanding allocations in this block group. We do
1369 * the ro check in case balance is currently acting on
1372 trace_btrfs_skip_unused_block_group(block_group
);
1373 spin_unlock(&block_group
->lock
);
1374 up_write(&space_info
->groups_sem
);
1377 spin_unlock(&block_group
->lock
);
1379 /* We don't want to force the issue, only flip if it's ok. */
1380 ret
= inc_block_group_ro(block_group
, 0);
1381 up_write(&space_info
->groups_sem
);
1388 * Want to do this before we do anything else so we can recover
1389 * properly if we fail to join the transaction.
1391 trans
= btrfs_start_trans_remove_block_group(fs_info
,
1392 block_group
->start
);
1393 if (IS_ERR(trans
)) {
1394 btrfs_dec_block_group_ro(block_group
);
1395 ret
= PTR_ERR(trans
);
1400 * We could have pending pinned extents for this block group,
1401 * just delete them, we don't care about them anymore.
1403 if (!clean_pinned_extents(trans
, block_group
))
1407 * At this point, the block_group is read only and should fail
1408 * new allocations. However, btrfs_finish_extent_commit() can
1409 * cause this block_group to be placed back on the discard
1410 * lists because now the block_group isn't fully discarded.
1411 * Bail here and try again later after discarding everything.
1413 spin_lock(&fs_info
->discard_ctl
.lock
);
1414 if (!list_empty(&block_group
->discard_list
)) {
1415 spin_unlock(&fs_info
->discard_ctl
.lock
);
1416 btrfs_dec_block_group_ro(block_group
);
1417 btrfs_discard_queue_work(&fs_info
->discard_ctl
,
1421 spin_unlock(&fs_info
->discard_ctl
.lock
);
1423 /* Reset pinned so btrfs_put_block_group doesn't complain */
1424 spin_lock(&space_info
->lock
);
1425 spin_lock(&block_group
->lock
);
1427 btrfs_space_info_update_bytes_pinned(fs_info
, space_info
,
1428 -block_group
->pinned
);
1429 space_info
->bytes_readonly
+= block_group
->pinned
;
1430 percpu_counter_add_batch(&space_info
->total_bytes_pinned
,
1431 -block_group
->pinned
,
1432 BTRFS_TOTAL_BYTES_PINNED_BATCH
);
1433 block_group
->pinned
= 0;
1435 spin_unlock(&block_group
->lock
);
1436 spin_unlock(&space_info
->lock
);
1439 * The normal path here is an unused block group is passed here,
1440 * then trimming is handled in the transaction commit path.
1441 * Async discard interposes before this to do the trimming
1442 * before coming down the unused block group path as trimming
1443 * will no longer be done later in the transaction commit path.
1445 if (!async_trim_enabled
&& btrfs_test_opt(fs_info
, DISCARD_ASYNC
))
1448 /* DISCARD can flip during remount */
1449 trimming
= btrfs_test_opt(fs_info
, DISCARD_SYNC
);
1451 /* Implicit trim during transaction commit. */
1453 btrfs_get_block_group_trimming(block_group
);
1456 * Btrfs_remove_chunk will abort the transaction if things go
1459 ret
= btrfs_remove_chunk(trans
, block_group
->start
);
1463 btrfs_put_block_group_trimming(block_group
);
1468 * If we're not mounted with -odiscard, we can just forget
1469 * about this block group. Otherwise we'll need to wait
1470 * until transaction commit to do the actual discard.
1473 spin_lock(&fs_info
->unused_bgs_lock
);
1475 * A concurrent scrub might have added us to the list
1476 * fs_info->unused_bgs, so use a list_move operation
1477 * to add the block group to the deleted_bgs list.
1479 list_move(&block_group
->bg_list
,
1480 &trans
->transaction
->deleted_bgs
);
1481 spin_unlock(&fs_info
->unused_bgs_lock
);
1482 btrfs_get_block_group(block_group
);
1485 btrfs_end_transaction(trans
);
1487 mutex_unlock(&fs_info
->delete_unused_bgs_mutex
);
1488 btrfs_put_block_group(block_group
);
1489 spin_lock(&fs_info
->unused_bgs_lock
);
1491 spin_unlock(&fs_info
->unused_bgs_lock
);
1495 btrfs_end_transaction(trans
);
1496 mutex_unlock(&fs_info
->delete_unused_bgs_mutex
);
1497 btrfs_put_block_group(block_group
);
1498 btrfs_discard_punt_unused_bgs_list(fs_info
);
1501 void btrfs_mark_bg_unused(struct btrfs_block_group
*bg
)
1503 struct btrfs_fs_info
*fs_info
= bg
->fs_info
;
1505 spin_lock(&fs_info
->unused_bgs_lock
);
1506 if (list_empty(&bg
->bg_list
)) {
1507 btrfs_get_block_group(bg
);
1508 trace_btrfs_add_unused_block_group(bg
);
1509 list_add_tail(&bg
->bg_list
, &fs_info
->unused_bgs
);
1511 spin_unlock(&fs_info
->unused_bgs_lock
);
1514 static int find_first_block_group(struct btrfs_fs_info
*fs_info
,
1515 struct btrfs_path
*path
,
1516 struct btrfs_key
*key
)
1518 struct btrfs_root
*root
= fs_info
->extent_root
;
1520 struct btrfs_key found_key
;
1521 struct extent_buffer
*leaf
;
1522 struct btrfs_block_group_item bg
;
1526 ret
= btrfs_search_slot(NULL
, root
, key
, path
, 0, 0);
1531 slot
= path
->slots
[0];
1532 leaf
= path
->nodes
[0];
1533 if (slot
>= btrfs_header_nritems(leaf
)) {
1534 ret
= btrfs_next_leaf(root
, path
);
1541 btrfs_item_key_to_cpu(leaf
, &found_key
, slot
);
1543 if (found_key
.objectid
>= key
->objectid
&&
1544 found_key
.type
== BTRFS_BLOCK_GROUP_ITEM_KEY
) {
1545 struct extent_map_tree
*em_tree
;
1546 struct extent_map
*em
;
1548 em_tree
= &root
->fs_info
->mapping_tree
;
1549 read_lock(&em_tree
->lock
);
1550 em
= lookup_extent_mapping(em_tree
, found_key
.objectid
,
1552 read_unlock(&em_tree
->lock
);
1555 "logical %llu len %llu found bg but no related chunk",
1556 found_key
.objectid
, found_key
.offset
);
1558 } else if (em
->start
!= found_key
.objectid
||
1559 em
->len
!= found_key
.offset
) {
1561 "block group %llu len %llu mismatch with chunk %llu len %llu",
1562 found_key
.objectid
, found_key
.offset
,
1563 em
->start
, em
->len
);
1566 read_extent_buffer(leaf
, &bg
,
1567 btrfs_item_ptr_offset(leaf
, slot
),
1569 flags
= btrfs_stack_block_group_flags(&bg
) &
1570 BTRFS_BLOCK_GROUP_TYPE_MASK
;
1572 if (flags
!= (em
->map_lookup
->type
&
1573 BTRFS_BLOCK_GROUP_TYPE_MASK
)) {
1575 "block group %llu len %llu type flags 0x%llx mismatch with chunk type flags 0x%llx",
1577 found_key
.offset
, flags
,
1578 (BTRFS_BLOCK_GROUP_TYPE_MASK
&
1579 em
->map_lookup
->type
));
1585 free_extent_map(em
);
1594 static void set_avail_alloc_bits(struct btrfs_fs_info
*fs_info
, u64 flags
)
1596 u64 extra_flags
= chunk_to_extended(flags
) &
1597 BTRFS_EXTENDED_PROFILE_MASK
;
1599 write_seqlock(&fs_info
->profiles_lock
);
1600 if (flags
& BTRFS_BLOCK_GROUP_DATA
)
1601 fs_info
->avail_data_alloc_bits
|= extra_flags
;
1602 if (flags
& BTRFS_BLOCK_GROUP_METADATA
)
1603 fs_info
->avail_metadata_alloc_bits
|= extra_flags
;
1604 if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
)
1605 fs_info
->avail_system_alloc_bits
|= extra_flags
;
1606 write_sequnlock(&fs_info
->profiles_lock
);
1610 * btrfs_rmap_block - Map a physical disk address to a list of logical addresses
1611 * @chunk_start: logical address of block group
1612 * @physical: physical address to map to logical addresses
1613 * @logical: return array of logical addresses which map to @physical
1614 * @naddrs: length of @logical
1615 * @stripe_len: size of IO stripe for the given block group
1617 * Maps a particular @physical disk address to a list of @logical addresses.
1618 * Used primarily to exclude those portions of a block group that contain super
1622 int btrfs_rmap_block(struct btrfs_fs_info
*fs_info
, u64 chunk_start
,
1623 u64 physical
, u64
**logical
, int *naddrs
, int *stripe_len
)
1625 struct extent_map
*em
;
1626 struct map_lookup
*map
;
1629 u64 data_stripe_length
;
1634 em
= btrfs_get_chunk_map(fs_info
, chunk_start
, 1);
1638 map
= em
->map_lookup
;
1639 data_stripe_length
= em
->len
;
1640 io_stripe_size
= map
->stripe_len
;
1642 if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
)
1643 data_stripe_length
= div_u64(data_stripe_length
,
1644 map
->num_stripes
/ map
->sub_stripes
);
1645 else if (map
->type
& BTRFS_BLOCK_GROUP_RAID0
)
1646 data_stripe_length
= div_u64(data_stripe_length
, map
->num_stripes
);
1647 else if (map
->type
& BTRFS_BLOCK_GROUP_RAID56_MASK
) {
1648 data_stripe_length
= div_u64(data_stripe_length
,
1649 nr_data_stripes(map
));
1650 io_stripe_size
= map
->stripe_len
* nr_data_stripes(map
);
1653 buf
= kcalloc(map
->num_stripes
, sizeof(u64
), GFP_NOFS
);
1659 for (i
= 0; i
< map
->num_stripes
; i
++) {
1660 bool already_inserted
= false;
1664 if (!in_range(physical
, map
->stripes
[i
].physical
,
1665 data_stripe_length
))
1668 stripe_nr
= physical
- map
->stripes
[i
].physical
;
1669 stripe_nr
= div64_u64(stripe_nr
, map
->stripe_len
);
1671 if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
) {
1672 stripe_nr
= stripe_nr
* map
->num_stripes
+ i
;
1673 stripe_nr
= div_u64(stripe_nr
, map
->sub_stripes
);
1674 } else if (map
->type
& BTRFS_BLOCK_GROUP_RAID0
) {
1675 stripe_nr
= stripe_nr
* map
->num_stripes
+ i
;
1678 * The remaining case would be for RAID56, multiply by
1679 * nr_data_stripes(). Alternatively, just use rmap_len below
1680 * instead of map->stripe_len
1683 bytenr
= chunk_start
+ stripe_nr
* io_stripe_size
;
1685 /* Ensure we don't add duplicate addresses */
1686 for (j
= 0; j
< nr
; j
++) {
1687 if (buf
[j
] == bytenr
) {
1688 already_inserted
= true;
1693 if (!already_inserted
)
1699 *stripe_len
= io_stripe_size
;
1701 free_extent_map(em
);
1705 static int exclude_super_stripes(struct btrfs_block_group
*cache
)
1707 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
1713 if (cache
->start
< BTRFS_SUPER_INFO_OFFSET
) {
1714 stripe_len
= BTRFS_SUPER_INFO_OFFSET
- cache
->start
;
1715 cache
->bytes_super
+= stripe_len
;
1716 ret
= btrfs_add_excluded_extent(fs_info
, cache
->start
,
1722 for (i
= 0; i
< BTRFS_SUPER_MIRROR_MAX
; i
++) {
1723 bytenr
= btrfs_sb_offset(i
);
1724 ret
= btrfs_rmap_block(fs_info
, cache
->start
,
1725 bytenr
, &logical
, &nr
, &stripe_len
);
1732 if (logical
[nr
] > cache
->start
+ cache
->length
)
1735 if (logical
[nr
] + stripe_len
<= cache
->start
)
1738 start
= logical
[nr
];
1739 if (start
< cache
->start
) {
1740 start
= cache
->start
;
1741 len
= (logical
[nr
] + stripe_len
) - start
;
1743 len
= min_t(u64
, stripe_len
,
1744 cache
->start
+ cache
->length
- start
);
1747 cache
->bytes_super
+= len
;
1748 ret
= btrfs_add_excluded_extent(fs_info
, start
, len
);
1760 static void link_block_group(struct btrfs_block_group
*cache
)
1762 struct btrfs_space_info
*space_info
= cache
->space_info
;
1763 int index
= btrfs_bg_flags_to_raid_index(cache
->flags
);
1766 down_write(&space_info
->groups_sem
);
1767 if (list_empty(&space_info
->block_groups
[index
]))
1769 list_add_tail(&cache
->list
, &space_info
->block_groups
[index
]);
1770 up_write(&space_info
->groups_sem
);
1773 btrfs_sysfs_add_block_group_type(cache
);
1776 static struct btrfs_block_group
*btrfs_create_block_group_cache(
1777 struct btrfs_fs_info
*fs_info
, u64 start
, u64 size
)
1779 struct btrfs_block_group
*cache
;
1781 cache
= kzalloc(sizeof(*cache
), GFP_NOFS
);
1785 cache
->free_space_ctl
= kzalloc(sizeof(*cache
->free_space_ctl
),
1787 if (!cache
->free_space_ctl
) {
1792 cache
->start
= start
;
1793 cache
->length
= size
;
1795 cache
->fs_info
= fs_info
;
1796 cache
->full_stripe_len
= btrfs_full_stripe_len(fs_info
, start
);
1797 set_free_space_tree_thresholds(cache
);
1799 cache
->discard_index
= BTRFS_DISCARD_INDEX_UNUSED
;
1801 atomic_set(&cache
->count
, 1);
1802 spin_lock_init(&cache
->lock
);
1803 init_rwsem(&cache
->data_rwsem
);
1804 INIT_LIST_HEAD(&cache
->list
);
1805 INIT_LIST_HEAD(&cache
->cluster_list
);
1806 INIT_LIST_HEAD(&cache
->bg_list
);
1807 INIT_LIST_HEAD(&cache
->ro_list
);
1808 INIT_LIST_HEAD(&cache
->discard_list
);
1809 INIT_LIST_HEAD(&cache
->dirty_list
);
1810 INIT_LIST_HEAD(&cache
->io_list
);
1811 btrfs_init_free_space_ctl(cache
);
1812 atomic_set(&cache
->trimming
, 0);
1813 mutex_init(&cache
->free_space_lock
);
1814 btrfs_init_full_stripe_locks_tree(&cache
->full_stripe_locks_root
);
1820 * Iterate all chunks and verify that each of them has the corresponding block
1823 static int check_chunk_block_group_mappings(struct btrfs_fs_info
*fs_info
)
1825 struct extent_map_tree
*map_tree
= &fs_info
->mapping_tree
;
1826 struct extent_map
*em
;
1827 struct btrfs_block_group
*bg
;
1832 read_lock(&map_tree
->lock
);
1834 * lookup_extent_mapping will return the first extent map
1835 * intersecting the range, so setting @len to 1 is enough to
1836 * get the first chunk.
1838 em
= lookup_extent_mapping(map_tree
, start
, 1);
1839 read_unlock(&map_tree
->lock
);
1843 bg
= btrfs_lookup_block_group(fs_info
, em
->start
);
1846 "chunk start=%llu len=%llu doesn't have corresponding block group",
1847 em
->start
, em
->len
);
1849 free_extent_map(em
);
1852 if (bg
->start
!= em
->start
|| bg
->length
!= em
->len
||
1853 (bg
->flags
& BTRFS_BLOCK_GROUP_TYPE_MASK
) !=
1854 (em
->map_lookup
->type
& BTRFS_BLOCK_GROUP_TYPE_MASK
)) {
1856 "chunk start=%llu len=%llu flags=0x%llx doesn't match block group start=%llu len=%llu flags=0x%llx",
1858 em
->map_lookup
->type
& BTRFS_BLOCK_GROUP_TYPE_MASK
,
1859 bg
->start
, bg
->length
,
1860 bg
->flags
& BTRFS_BLOCK_GROUP_TYPE_MASK
);
1862 free_extent_map(em
);
1863 btrfs_put_block_group(bg
);
1866 start
= em
->start
+ em
->len
;
1867 free_extent_map(em
);
1868 btrfs_put_block_group(bg
);
1873 static int read_one_block_group(struct btrfs_fs_info
*info
,
1874 struct btrfs_path
*path
,
1875 const struct btrfs_key
*key
,
1878 struct extent_buffer
*leaf
= path
->nodes
[0];
1879 struct btrfs_block_group
*cache
;
1880 struct btrfs_space_info
*space_info
;
1881 struct btrfs_block_group_item bgi
;
1882 const bool mixed
= btrfs_fs_incompat(info
, MIXED_GROUPS
);
1883 int slot
= path
->slots
[0];
1886 ASSERT(key
->type
== BTRFS_BLOCK_GROUP_ITEM_KEY
);
1888 cache
= btrfs_create_block_group_cache(info
, key
->objectid
, key
->offset
);
1894 * When we mount with old space cache, we need to
1895 * set BTRFS_DC_CLEAR and set dirty flag.
1897 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
1898 * truncate the old free space cache inode and
1900 * b) Setting 'dirty flag' makes sure that we flush
1901 * the new space cache info onto disk.
1903 if (btrfs_test_opt(info
, SPACE_CACHE
))
1904 cache
->disk_cache_state
= BTRFS_DC_CLEAR
;
1906 read_extent_buffer(leaf
, &bgi
, btrfs_item_ptr_offset(leaf
, slot
),
1908 cache
->used
= btrfs_stack_block_group_used(&bgi
);
1909 cache
->flags
= btrfs_stack_block_group_flags(&bgi
);
1910 if (!mixed
&& ((cache
->flags
& BTRFS_BLOCK_GROUP_METADATA
) &&
1911 (cache
->flags
& BTRFS_BLOCK_GROUP_DATA
))) {
1913 "bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups",
1920 * We need to exclude the super stripes now so that the space info has
1921 * super bytes accounted for, otherwise we'll think we have more space
1922 * than we actually do.
1924 ret
= exclude_super_stripes(cache
);
1926 /* We may have excluded something, so call this just in case. */
1927 btrfs_free_excluded_extents(cache
);
1932 * Check for two cases, either we are full, and therefore don't need
1933 * to bother with the caching work since we won't find any space, or we
1934 * are empty, and we can just add all the space in and be done with it.
1935 * This saves us _a_lot_ of time, particularly in the full case.
1937 if (key
->offset
== cache
->used
) {
1938 cache
->last_byte_to_unpin
= (u64
)-1;
1939 cache
->cached
= BTRFS_CACHE_FINISHED
;
1940 btrfs_free_excluded_extents(cache
);
1941 } else if (cache
->used
== 0) {
1942 cache
->last_byte_to_unpin
= (u64
)-1;
1943 cache
->cached
= BTRFS_CACHE_FINISHED
;
1944 add_new_free_space(cache
, key
->objectid
,
1945 key
->objectid
+ key
->offset
);
1946 btrfs_free_excluded_extents(cache
);
1949 ret
= btrfs_add_block_group_cache(info
, cache
);
1951 btrfs_remove_free_space_cache(cache
);
1954 trace_btrfs_add_block_group(info
, cache
, 0);
1955 btrfs_update_space_info(info
, cache
->flags
, key
->offset
,
1956 cache
->used
, cache
->bytes_super
, &space_info
);
1958 cache
->space_info
= space_info
;
1960 link_block_group(cache
);
1962 set_avail_alloc_bits(info
, cache
->flags
);
1963 if (btrfs_chunk_readonly(info
, cache
->start
)) {
1964 inc_block_group_ro(cache
, 1);
1965 } else if (cache
->used
== 0) {
1966 ASSERT(list_empty(&cache
->bg_list
));
1967 if (btrfs_test_opt(info
, DISCARD_ASYNC
))
1968 btrfs_discard_queue_work(&info
->discard_ctl
, cache
);
1970 btrfs_mark_bg_unused(cache
);
1974 btrfs_put_block_group(cache
);
1978 int btrfs_read_block_groups(struct btrfs_fs_info
*info
)
1980 struct btrfs_path
*path
;
1982 struct btrfs_block_group
*cache
;
1983 struct btrfs_space_info
*space_info
;
1984 struct btrfs_key key
;
1990 key
.type
= BTRFS_BLOCK_GROUP_ITEM_KEY
;
1991 path
= btrfs_alloc_path();
1994 path
->reada
= READA_FORWARD
;
1996 cache_gen
= btrfs_super_cache_generation(info
->super_copy
);
1997 if (btrfs_test_opt(info
, SPACE_CACHE
) &&
1998 btrfs_super_generation(info
->super_copy
) != cache_gen
)
2000 if (btrfs_test_opt(info
, CLEAR_CACHE
))
2004 ret
= find_first_block_group(info
, path
, &key
);
2010 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
2011 ret
= read_one_block_group(info
, path
, &key
, need_clear
);
2014 key
.objectid
+= key
.offset
;
2016 btrfs_release_path(path
);
2020 list_for_each_entry_rcu(space_info
, &info
->space_info
, list
) {
2021 if (!(btrfs_get_alloc_profile(info
, space_info
->flags
) &
2022 (BTRFS_BLOCK_GROUP_RAID10
|
2023 BTRFS_BLOCK_GROUP_RAID1_MASK
|
2024 BTRFS_BLOCK_GROUP_RAID56_MASK
|
2025 BTRFS_BLOCK_GROUP_DUP
)))
2028 * Avoid allocating from un-mirrored block group if there are
2029 * mirrored block groups.
2031 list_for_each_entry(cache
,
2032 &space_info
->block_groups
[BTRFS_RAID_RAID0
],
2034 inc_block_group_ro(cache
, 1);
2035 list_for_each_entry(cache
,
2036 &space_info
->block_groups
[BTRFS_RAID_SINGLE
],
2038 inc_block_group_ro(cache
, 1);
2042 btrfs_init_global_block_rsv(info
);
2043 ret
= check_chunk_block_group_mappings(info
);
2045 btrfs_free_path(path
);
2049 void btrfs_create_pending_block_groups(struct btrfs_trans_handle
*trans
)
2051 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2052 struct btrfs_block_group
*block_group
;
2053 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
2054 struct btrfs_block_group_item item
;
2055 struct btrfs_key key
;
2058 if (!trans
->can_flush_pending_bgs
)
2061 while (!list_empty(&trans
->new_bgs
)) {
2062 block_group
= list_first_entry(&trans
->new_bgs
,
2063 struct btrfs_block_group
,
2068 spin_lock(&block_group
->lock
);
2069 btrfs_set_stack_block_group_used(&item
, block_group
->used
);
2070 btrfs_set_stack_block_group_chunk_objectid(&item
,
2071 BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
2072 btrfs_set_stack_block_group_flags(&item
, block_group
->flags
);
2073 key
.objectid
= block_group
->start
;
2074 key
.type
= BTRFS_BLOCK_GROUP_ITEM_KEY
;
2075 key
.offset
= block_group
->length
;
2076 spin_unlock(&block_group
->lock
);
2078 ret
= btrfs_insert_item(trans
, extent_root
, &key
, &item
,
2081 btrfs_abort_transaction(trans
, ret
);
2082 ret
= btrfs_finish_chunk_alloc(trans
, key
.objectid
, key
.offset
);
2084 btrfs_abort_transaction(trans
, ret
);
2085 add_block_group_free_space(trans
, block_group
);
2086 /* Already aborted the transaction if it failed. */
2088 btrfs_delayed_refs_rsv_release(fs_info
, 1);
2089 list_del_init(&block_group
->bg_list
);
2091 btrfs_trans_release_chunk_metadata(trans
);
2094 int btrfs_make_block_group(struct btrfs_trans_handle
*trans
, u64 bytes_used
,
2095 u64 type
, u64 chunk_offset
, u64 size
)
2097 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2098 struct btrfs_block_group
*cache
;
2101 btrfs_set_log_full_commit(trans
);
2103 cache
= btrfs_create_block_group_cache(fs_info
, chunk_offset
, size
);
2107 cache
->used
= bytes_used
;
2108 cache
->flags
= type
;
2109 cache
->last_byte_to_unpin
= (u64
)-1;
2110 cache
->cached
= BTRFS_CACHE_FINISHED
;
2111 cache
->needs_free_space
= 1;
2112 ret
= exclude_super_stripes(cache
);
2114 /* We may have excluded something, so call this just in case */
2115 btrfs_free_excluded_extents(cache
);
2116 btrfs_put_block_group(cache
);
2120 add_new_free_space(cache
, chunk_offset
, chunk_offset
+ size
);
2122 btrfs_free_excluded_extents(cache
);
2124 #ifdef CONFIG_BTRFS_DEBUG
2125 if (btrfs_should_fragment_free_space(cache
)) {
2126 u64 new_bytes_used
= size
- bytes_used
;
2128 bytes_used
+= new_bytes_used
>> 1;
2129 fragment_free_space(cache
);
2133 * Ensure the corresponding space_info object is created and
2134 * assigned to our block group. We want our bg to be added to the rbtree
2135 * with its ->space_info set.
2137 cache
->space_info
= btrfs_find_space_info(fs_info
, cache
->flags
);
2138 ASSERT(cache
->space_info
);
2140 ret
= btrfs_add_block_group_cache(fs_info
, cache
);
2142 btrfs_remove_free_space_cache(cache
);
2143 btrfs_put_block_group(cache
);
2148 * Now that our block group has its ->space_info set and is inserted in
2149 * the rbtree, update the space info's counters.
2151 trace_btrfs_add_block_group(fs_info
, cache
, 1);
2152 btrfs_update_space_info(fs_info
, cache
->flags
, size
, bytes_used
,
2153 cache
->bytes_super
, &cache
->space_info
);
2154 btrfs_update_global_block_rsv(fs_info
);
2156 link_block_group(cache
);
2158 list_add_tail(&cache
->bg_list
, &trans
->new_bgs
);
2159 trans
->delayed_ref_updates
++;
2160 btrfs_update_delayed_refs_rsv(trans
);
2162 set_avail_alloc_bits(fs_info
, type
);
2166 static u64
update_block_group_flags(struct btrfs_fs_info
*fs_info
, u64 flags
)
2172 * if restripe for this chunk_type is on pick target profile and
2173 * return, otherwise do the usual balance
2175 stripped
= get_restripe_target(fs_info
, flags
);
2177 return extended_to_chunk(stripped
);
2179 num_devices
= fs_info
->fs_devices
->rw_devices
;
2181 stripped
= BTRFS_BLOCK_GROUP_RAID0
| BTRFS_BLOCK_GROUP_RAID56_MASK
|
2182 BTRFS_BLOCK_GROUP_RAID1_MASK
| BTRFS_BLOCK_GROUP_RAID10
;
2184 if (num_devices
== 1) {
2185 stripped
|= BTRFS_BLOCK_GROUP_DUP
;
2186 stripped
= flags
& ~stripped
;
2188 /* turn raid0 into single device chunks */
2189 if (flags
& BTRFS_BLOCK_GROUP_RAID0
)
2192 /* turn mirroring into duplication */
2193 if (flags
& (BTRFS_BLOCK_GROUP_RAID1_MASK
|
2194 BTRFS_BLOCK_GROUP_RAID10
))
2195 return stripped
| BTRFS_BLOCK_GROUP_DUP
;
2197 /* they already had raid on here, just return */
2198 if (flags
& stripped
)
2201 stripped
|= BTRFS_BLOCK_GROUP_DUP
;
2202 stripped
= flags
& ~stripped
;
2204 /* switch duplicated blocks with raid1 */
2205 if (flags
& BTRFS_BLOCK_GROUP_DUP
)
2206 return stripped
| BTRFS_BLOCK_GROUP_RAID1
;
2208 /* this is drive concat, leave it alone */
2215 * Mark one block group RO, can be called several times for the same block
2218 * @cache: the destination block group
2219 * @do_chunk_alloc: whether need to do chunk pre-allocation, this is to
2220 * ensure we still have some free space after marking this
2223 int btrfs_inc_block_group_ro(struct btrfs_block_group
*cache
,
2224 bool do_chunk_alloc
)
2226 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
2227 struct btrfs_trans_handle
*trans
;
2232 trans
= btrfs_join_transaction(fs_info
->extent_root
);
2234 return PTR_ERR(trans
);
2237 * we're not allowed to set block groups readonly after the dirty
2238 * block groups cache has started writing. If it already started,
2239 * back off and let this transaction commit
2241 mutex_lock(&fs_info
->ro_block_group_mutex
);
2242 if (test_bit(BTRFS_TRANS_DIRTY_BG_RUN
, &trans
->transaction
->flags
)) {
2243 u64 transid
= trans
->transid
;
2245 mutex_unlock(&fs_info
->ro_block_group_mutex
);
2246 btrfs_end_transaction(trans
);
2248 ret
= btrfs_wait_for_commit(fs_info
, transid
);
2254 if (do_chunk_alloc
) {
2256 * If we are changing raid levels, try to allocate a
2257 * corresponding block group with the new raid level.
2259 alloc_flags
= update_block_group_flags(fs_info
, cache
->flags
);
2260 if (alloc_flags
!= cache
->flags
) {
2261 ret
= btrfs_chunk_alloc(trans
, alloc_flags
,
2264 * ENOSPC is allowed here, we may have enough space
2265 * already allocated at the new raid level to carry on
2274 ret
= inc_block_group_ro(cache
, 0);
2275 if (!do_chunk_alloc
)
2279 alloc_flags
= btrfs_get_alloc_profile(fs_info
, cache
->space_info
->flags
);
2280 ret
= btrfs_chunk_alloc(trans
, alloc_flags
, CHUNK_ALLOC_FORCE
);
2283 ret
= inc_block_group_ro(cache
, 0);
2285 if (cache
->flags
& BTRFS_BLOCK_GROUP_SYSTEM
) {
2286 alloc_flags
= update_block_group_flags(fs_info
, cache
->flags
);
2287 mutex_lock(&fs_info
->chunk_mutex
);
2288 check_system_chunk(trans
, alloc_flags
);
2289 mutex_unlock(&fs_info
->chunk_mutex
);
2292 mutex_unlock(&fs_info
->ro_block_group_mutex
);
2294 btrfs_end_transaction(trans
);
2298 void btrfs_dec_block_group_ro(struct btrfs_block_group
*cache
)
2300 struct btrfs_space_info
*sinfo
= cache
->space_info
;
2305 spin_lock(&sinfo
->lock
);
2306 spin_lock(&cache
->lock
);
2308 num_bytes
= cache
->length
- cache
->reserved
-
2309 cache
->pinned
- cache
->bytes_super
- cache
->used
;
2310 sinfo
->bytes_readonly
-= num_bytes
;
2311 list_del_init(&cache
->ro_list
);
2313 spin_unlock(&cache
->lock
);
2314 spin_unlock(&sinfo
->lock
);
2317 static int write_one_cache_group(struct btrfs_trans_handle
*trans
,
2318 struct btrfs_path
*path
,
2319 struct btrfs_block_group
*cache
)
2321 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2323 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
2325 struct extent_buffer
*leaf
;
2326 struct btrfs_block_group_item bgi
;
2327 struct btrfs_key key
;
2329 key
.objectid
= cache
->start
;
2330 key
.type
= BTRFS_BLOCK_GROUP_ITEM_KEY
;
2331 key
.offset
= cache
->length
;
2333 ret
= btrfs_search_slot(trans
, extent_root
, &key
, path
, 0, 1);
2340 leaf
= path
->nodes
[0];
2341 bi
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2342 btrfs_set_stack_block_group_used(&bgi
, cache
->used
);
2343 btrfs_set_stack_block_group_chunk_objectid(&bgi
,
2344 BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
2345 btrfs_set_stack_block_group_flags(&bgi
, cache
->flags
);
2346 write_extent_buffer(leaf
, &bgi
, bi
, sizeof(bgi
));
2347 btrfs_mark_buffer_dirty(leaf
);
2349 btrfs_release_path(path
);
2354 static int cache_save_setup(struct btrfs_block_group
*block_group
,
2355 struct btrfs_trans_handle
*trans
,
2356 struct btrfs_path
*path
)
2358 struct btrfs_fs_info
*fs_info
= block_group
->fs_info
;
2359 struct btrfs_root
*root
= fs_info
->tree_root
;
2360 struct inode
*inode
= NULL
;
2361 struct extent_changeset
*data_reserved
= NULL
;
2363 int dcs
= BTRFS_DC_ERROR
;
2369 * If this block group is smaller than 100 megs don't bother caching the
2372 if (block_group
->length
< (100 * SZ_1M
)) {
2373 spin_lock(&block_group
->lock
);
2374 block_group
->disk_cache_state
= BTRFS_DC_WRITTEN
;
2375 spin_unlock(&block_group
->lock
);
2379 if (TRANS_ABORTED(trans
))
2382 inode
= lookup_free_space_inode(block_group
, path
);
2383 if (IS_ERR(inode
) && PTR_ERR(inode
) != -ENOENT
) {
2384 ret
= PTR_ERR(inode
);
2385 btrfs_release_path(path
);
2389 if (IS_ERR(inode
)) {
2393 if (block_group
->ro
)
2396 ret
= create_free_space_inode(trans
, block_group
, path
);
2403 * We want to set the generation to 0, that way if anything goes wrong
2404 * from here on out we know not to trust this cache when we load up next
2407 BTRFS_I(inode
)->generation
= 0;
2408 ret
= btrfs_update_inode(trans
, root
, inode
);
2411 * So theoretically we could recover from this, simply set the
2412 * super cache generation to 0 so we know to invalidate the
2413 * cache, but then we'd have to keep track of the block groups
2414 * that fail this way so we know we _have_ to reset this cache
2415 * before the next commit or risk reading stale cache. So to
2416 * limit our exposure to horrible edge cases lets just abort the
2417 * transaction, this only happens in really bad situations
2420 btrfs_abort_transaction(trans
, ret
);
2425 /* We've already setup this transaction, go ahead and exit */
2426 if (block_group
->cache_generation
== trans
->transid
&&
2427 i_size_read(inode
)) {
2428 dcs
= BTRFS_DC_SETUP
;
2432 if (i_size_read(inode
) > 0) {
2433 ret
= btrfs_check_trunc_cache_free_space(fs_info
,
2434 &fs_info
->global_block_rsv
);
2438 ret
= btrfs_truncate_free_space_cache(trans
, NULL
, inode
);
2443 spin_lock(&block_group
->lock
);
2444 if (block_group
->cached
!= BTRFS_CACHE_FINISHED
||
2445 !btrfs_test_opt(fs_info
, SPACE_CACHE
)) {
2447 * don't bother trying to write stuff out _if_
2448 * a) we're not cached,
2449 * b) we're with nospace_cache mount option,
2450 * c) we're with v2 space_cache (FREE_SPACE_TREE).
2452 dcs
= BTRFS_DC_WRITTEN
;
2453 spin_unlock(&block_group
->lock
);
2456 spin_unlock(&block_group
->lock
);
2459 * We hit an ENOSPC when setting up the cache in this transaction, just
2460 * skip doing the setup, we've already cleared the cache so we're safe.
2462 if (test_bit(BTRFS_TRANS_CACHE_ENOSPC
, &trans
->transaction
->flags
)) {
2468 * Try to preallocate enough space based on how big the block group is.
2469 * Keep in mind this has to include any pinned space which could end up
2470 * taking up quite a bit since it's not folded into the other space
2473 num_pages
= div_u64(block_group
->length
, SZ_256M
);
2478 num_pages
*= PAGE_SIZE
;
2480 ret
= btrfs_check_data_free_space(inode
, &data_reserved
, 0, num_pages
);
2484 ret
= btrfs_prealloc_file_range_trans(inode
, trans
, 0, 0, num_pages
,
2485 num_pages
, num_pages
,
2488 * Our cache requires contiguous chunks so that we don't modify a bunch
2489 * of metadata or split extents when writing the cache out, which means
2490 * we can enospc if we are heavily fragmented in addition to just normal
2491 * out of space conditions. So if we hit this just skip setting up any
2492 * other block groups for this transaction, maybe we'll unpin enough
2493 * space the next time around.
2496 dcs
= BTRFS_DC_SETUP
;
2497 else if (ret
== -ENOSPC
)
2498 set_bit(BTRFS_TRANS_CACHE_ENOSPC
, &trans
->transaction
->flags
);
2503 btrfs_release_path(path
);
2505 spin_lock(&block_group
->lock
);
2506 if (!ret
&& dcs
== BTRFS_DC_SETUP
)
2507 block_group
->cache_generation
= trans
->transid
;
2508 block_group
->disk_cache_state
= dcs
;
2509 spin_unlock(&block_group
->lock
);
2511 extent_changeset_free(data_reserved
);
2515 int btrfs_setup_space_cache(struct btrfs_trans_handle
*trans
)
2517 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2518 struct btrfs_block_group
*cache
, *tmp
;
2519 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
2520 struct btrfs_path
*path
;
2522 if (list_empty(&cur_trans
->dirty_bgs
) ||
2523 !btrfs_test_opt(fs_info
, SPACE_CACHE
))
2526 path
= btrfs_alloc_path();
2530 /* Could add new block groups, use _safe just in case */
2531 list_for_each_entry_safe(cache
, tmp
, &cur_trans
->dirty_bgs
,
2533 if (cache
->disk_cache_state
== BTRFS_DC_CLEAR
)
2534 cache_save_setup(cache
, trans
, path
);
2537 btrfs_free_path(path
);
2542 * Transaction commit does final block group cache writeback during a critical
2543 * section where nothing is allowed to change the FS. This is required in
2544 * order for the cache to actually match the block group, but can introduce a
2545 * lot of latency into the commit.
2547 * So, btrfs_start_dirty_block_groups is here to kick off block group cache IO.
2548 * There's a chance we'll have to redo some of it if the block group changes
2549 * again during the commit, but it greatly reduces the commit latency by
2550 * getting rid of the easy block groups while we're still allowing others to
2553 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle
*trans
)
2555 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2556 struct btrfs_block_group
*cache
;
2557 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
2560 struct btrfs_path
*path
= NULL
;
2562 struct list_head
*io
= &cur_trans
->io_bgs
;
2563 int num_started
= 0;
2566 spin_lock(&cur_trans
->dirty_bgs_lock
);
2567 if (list_empty(&cur_trans
->dirty_bgs
)) {
2568 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2571 list_splice_init(&cur_trans
->dirty_bgs
, &dirty
);
2572 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2575 /* Make sure all the block groups on our dirty list actually exist */
2576 btrfs_create_pending_block_groups(trans
);
2579 path
= btrfs_alloc_path();
2585 * cache_write_mutex is here only to save us from balance or automatic
2586 * removal of empty block groups deleting this block group while we are
2587 * writing out the cache
2589 mutex_lock(&trans
->transaction
->cache_write_mutex
);
2590 while (!list_empty(&dirty
)) {
2591 bool drop_reserve
= true;
2593 cache
= list_first_entry(&dirty
, struct btrfs_block_group
,
2596 * This can happen if something re-dirties a block group that
2597 * is already under IO. Just wait for it to finish and then do
2600 if (!list_empty(&cache
->io_list
)) {
2601 list_del_init(&cache
->io_list
);
2602 btrfs_wait_cache_io(trans
, cache
, path
);
2603 btrfs_put_block_group(cache
);
2608 * btrfs_wait_cache_io uses the cache->dirty_list to decide if
2609 * it should update the cache_state. Don't delete until after
2612 * Since we're not running in the commit critical section
2613 * we need the dirty_bgs_lock to protect from update_block_group
2615 spin_lock(&cur_trans
->dirty_bgs_lock
);
2616 list_del_init(&cache
->dirty_list
);
2617 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2621 cache_save_setup(cache
, trans
, path
);
2623 if (cache
->disk_cache_state
== BTRFS_DC_SETUP
) {
2624 cache
->io_ctl
.inode
= NULL
;
2625 ret
= btrfs_write_out_cache(trans
, cache
, path
);
2626 if (ret
== 0 && cache
->io_ctl
.inode
) {
2631 * The cache_write_mutex is protecting the
2632 * io_list, also refer to the definition of
2633 * btrfs_transaction::io_bgs for more details
2635 list_add_tail(&cache
->io_list
, io
);
2638 * If we failed to write the cache, the
2639 * generation will be bad and life goes on
2645 ret
= write_one_cache_group(trans
, path
, cache
);
2647 * Our block group might still be attached to the list
2648 * of new block groups in the transaction handle of some
2649 * other task (struct btrfs_trans_handle->new_bgs). This
2650 * means its block group item isn't yet in the extent
2651 * tree. If this happens ignore the error, as we will
2652 * try again later in the critical section of the
2653 * transaction commit.
2655 if (ret
== -ENOENT
) {
2657 spin_lock(&cur_trans
->dirty_bgs_lock
);
2658 if (list_empty(&cache
->dirty_list
)) {
2659 list_add_tail(&cache
->dirty_list
,
2660 &cur_trans
->dirty_bgs
);
2661 btrfs_get_block_group(cache
);
2662 drop_reserve
= false;
2664 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2666 btrfs_abort_transaction(trans
, ret
);
2670 /* If it's not on the io list, we need to put the block group */
2672 btrfs_put_block_group(cache
);
2674 btrfs_delayed_refs_rsv_release(fs_info
, 1);
2680 * Avoid blocking other tasks for too long. It might even save
2681 * us from writing caches for block groups that are going to be
2684 mutex_unlock(&trans
->transaction
->cache_write_mutex
);
2685 mutex_lock(&trans
->transaction
->cache_write_mutex
);
2687 mutex_unlock(&trans
->transaction
->cache_write_mutex
);
2690 * Go through delayed refs for all the stuff we've just kicked off
2691 * and then loop back (just once)
2693 ret
= btrfs_run_delayed_refs(trans
, 0);
2694 if (!ret
&& loops
== 0) {
2696 spin_lock(&cur_trans
->dirty_bgs_lock
);
2697 list_splice_init(&cur_trans
->dirty_bgs
, &dirty
);
2699 * dirty_bgs_lock protects us from concurrent block group
2700 * deletes too (not just cache_write_mutex).
2702 if (!list_empty(&dirty
)) {
2703 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2706 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2707 } else if (ret
< 0) {
2708 btrfs_cleanup_dirty_bgs(cur_trans
, fs_info
);
2711 btrfs_free_path(path
);
2715 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle
*trans
)
2717 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2718 struct btrfs_block_group
*cache
;
2719 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
2722 struct btrfs_path
*path
;
2723 struct list_head
*io
= &cur_trans
->io_bgs
;
2724 int num_started
= 0;
2726 path
= btrfs_alloc_path();
2731 * Even though we are in the critical section of the transaction commit,
2732 * we can still have concurrent tasks adding elements to this
2733 * transaction's list of dirty block groups. These tasks correspond to
2734 * endio free space workers started when writeback finishes for a
2735 * space cache, which run inode.c:btrfs_finish_ordered_io(), and can
2736 * allocate new block groups as a result of COWing nodes of the root
2737 * tree when updating the free space inode. The writeback for the space
2738 * caches is triggered by an earlier call to
2739 * btrfs_start_dirty_block_groups() and iterations of the following
2741 * Also we want to do the cache_save_setup first and then run the
2742 * delayed refs to make sure we have the best chance at doing this all
2745 spin_lock(&cur_trans
->dirty_bgs_lock
);
2746 while (!list_empty(&cur_trans
->dirty_bgs
)) {
2747 cache
= list_first_entry(&cur_trans
->dirty_bgs
,
2748 struct btrfs_block_group
,
2752 * This can happen if cache_save_setup re-dirties a block group
2753 * that is already under IO. Just wait for it to finish and
2754 * then do it all again
2756 if (!list_empty(&cache
->io_list
)) {
2757 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2758 list_del_init(&cache
->io_list
);
2759 btrfs_wait_cache_io(trans
, cache
, path
);
2760 btrfs_put_block_group(cache
);
2761 spin_lock(&cur_trans
->dirty_bgs_lock
);
2765 * Don't remove from the dirty list until after we've waited on
2768 list_del_init(&cache
->dirty_list
);
2769 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2772 cache_save_setup(cache
, trans
, path
);
2775 ret
= btrfs_run_delayed_refs(trans
,
2776 (unsigned long) -1);
2778 if (!ret
&& cache
->disk_cache_state
== BTRFS_DC_SETUP
) {
2779 cache
->io_ctl
.inode
= NULL
;
2780 ret
= btrfs_write_out_cache(trans
, cache
, path
);
2781 if (ret
== 0 && cache
->io_ctl
.inode
) {
2784 list_add_tail(&cache
->io_list
, io
);
2787 * If we failed to write the cache, the
2788 * generation will be bad and life goes on
2794 ret
= write_one_cache_group(trans
, path
, cache
);
2796 * One of the free space endio workers might have
2797 * created a new block group while updating a free space
2798 * cache's inode (at inode.c:btrfs_finish_ordered_io())
2799 * and hasn't released its transaction handle yet, in
2800 * which case the new block group is still attached to
2801 * its transaction handle and its creation has not
2802 * finished yet (no block group item in the extent tree
2803 * yet, etc). If this is the case, wait for all free
2804 * space endio workers to finish and retry. This is a
2805 * a very rare case so no need for a more efficient and
2808 if (ret
== -ENOENT
) {
2809 wait_event(cur_trans
->writer_wait
,
2810 atomic_read(&cur_trans
->num_writers
) == 1);
2811 ret
= write_one_cache_group(trans
, path
, cache
);
2814 btrfs_abort_transaction(trans
, ret
);
2817 /* If its not on the io list, we need to put the block group */
2819 btrfs_put_block_group(cache
);
2820 btrfs_delayed_refs_rsv_release(fs_info
, 1);
2821 spin_lock(&cur_trans
->dirty_bgs_lock
);
2823 spin_unlock(&cur_trans
->dirty_bgs_lock
);
2826 * Refer to the definition of io_bgs member for details why it's safe
2827 * to use it without any locking
2829 while (!list_empty(io
)) {
2830 cache
= list_first_entry(io
, struct btrfs_block_group
,
2832 list_del_init(&cache
->io_list
);
2833 btrfs_wait_cache_io(trans
, cache
, path
);
2834 btrfs_put_block_group(cache
);
2837 btrfs_free_path(path
);
2841 int btrfs_update_block_group(struct btrfs_trans_handle
*trans
,
2842 u64 bytenr
, u64 num_bytes
, int alloc
)
2844 struct btrfs_fs_info
*info
= trans
->fs_info
;
2845 struct btrfs_block_group
*cache
= NULL
;
2846 u64 total
= num_bytes
;
2852 /* Block accounting for super block */
2853 spin_lock(&info
->delalloc_root_lock
);
2854 old_val
= btrfs_super_bytes_used(info
->super_copy
);
2856 old_val
+= num_bytes
;
2858 old_val
-= num_bytes
;
2859 btrfs_set_super_bytes_used(info
->super_copy
, old_val
);
2860 spin_unlock(&info
->delalloc_root_lock
);
2863 cache
= btrfs_lookup_block_group(info
, bytenr
);
2868 factor
= btrfs_bg_type_to_factor(cache
->flags
);
2871 * If this block group has free space cache written out, we
2872 * need to make sure to load it if we are removing space. This
2873 * is because we need the unpinning stage to actually add the
2874 * space back to the block group, otherwise we will leak space.
2876 if (!alloc
&& !btrfs_block_group_done(cache
))
2877 btrfs_cache_block_group(cache
, 1);
2879 byte_in_group
= bytenr
- cache
->start
;
2880 WARN_ON(byte_in_group
> cache
->length
);
2882 spin_lock(&cache
->space_info
->lock
);
2883 spin_lock(&cache
->lock
);
2885 if (btrfs_test_opt(info
, SPACE_CACHE
) &&
2886 cache
->disk_cache_state
< BTRFS_DC_CLEAR
)
2887 cache
->disk_cache_state
= BTRFS_DC_CLEAR
;
2889 old_val
= cache
->used
;
2890 num_bytes
= min(total
, cache
->length
- byte_in_group
);
2892 old_val
+= num_bytes
;
2893 cache
->used
= old_val
;
2894 cache
->reserved
-= num_bytes
;
2895 cache
->space_info
->bytes_reserved
-= num_bytes
;
2896 cache
->space_info
->bytes_used
+= num_bytes
;
2897 cache
->space_info
->disk_used
+= num_bytes
* factor
;
2898 spin_unlock(&cache
->lock
);
2899 spin_unlock(&cache
->space_info
->lock
);
2901 old_val
-= num_bytes
;
2902 cache
->used
= old_val
;
2903 cache
->pinned
+= num_bytes
;
2904 btrfs_space_info_update_bytes_pinned(info
,
2905 cache
->space_info
, num_bytes
);
2906 cache
->space_info
->bytes_used
-= num_bytes
;
2907 cache
->space_info
->disk_used
-= num_bytes
* factor
;
2908 spin_unlock(&cache
->lock
);
2909 spin_unlock(&cache
->space_info
->lock
);
2911 percpu_counter_add_batch(
2912 &cache
->space_info
->total_bytes_pinned
,
2914 BTRFS_TOTAL_BYTES_PINNED_BATCH
);
2915 set_extent_dirty(&trans
->transaction
->pinned_extents
,
2916 bytenr
, bytenr
+ num_bytes
- 1,
2917 GFP_NOFS
| __GFP_NOFAIL
);
2920 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
2921 if (list_empty(&cache
->dirty_list
)) {
2922 list_add_tail(&cache
->dirty_list
,
2923 &trans
->transaction
->dirty_bgs
);
2924 trans
->delayed_ref_updates
++;
2925 btrfs_get_block_group(cache
);
2927 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
2930 * No longer have used bytes in this block group, queue it for
2931 * deletion. We do this after adding the block group to the
2932 * dirty list to avoid races between cleaner kthread and space
2935 if (!alloc
&& old_val
== 0) {
2936 if (!btrfs_test_opt(info
, DISCARD_ASYNC
))
2937 btrfs_mark_bg_unused(cache
);
2940 btrfs_put_block_group(cache
);
2942 bytenr
+= num_bytes
;
2945 /* Modified block groups are accounted for in the delayed_refs_rsv. */
2946 btrfs_update_delayed_refs_rsv(trans
);
2951 * btrfs_add_reserved_bytes - update the block_group and space info counters
2952 * @cache: The cache we are manipulating
2953 * @ram_bytes: The number of bytes of file content, and will be same to
2954 * @num_bytes except for the compress path.
2955 * @num_bytes: The number of bytes in question
2956 * @delalloc: The blocks are allocated for the delalloc write
2958 * This is called by the allocator when it reserves space. If this is a
2959 * reservation and the block group has become read only we cannot make the
2960 * reservation and return -EAGAIN, otherwise this function always succeeds.
2962 int btrfs_add_reserved_bytes(struct btrfs_block_group
*cache
,
2963 u64 ram_bytes
, u64 num_bytes
, int delalloc
)
2965 struct btrfs_space_info
*space_info
= cache
->space_info
;
2968 spin_lock(&space_info
->lock
);
2969 spin_lock(&cache
->lock
);
2973 cache
->reserved
+= num_bytes
;
2974 space_info
->bytes_reserved
+= num_bytes
;
2975 trace_btrfs_space_reservation(cache
->fs_info
, "space_info",
2976 space_info
->flags
, num_bytes
, 1);
2977 btrfs_space_info_update_bytes_may_use(cache
->fs_info
,
2978 space_info
, -ram_bytes
);
2980 cache
->delalloc_bytes
+= num_bytes
;
2982 spin_unlock(&cache
->lock
);
2983 spin_unlock(&space_info
->lock
);
2988 * btrfs_free_reserved_bytes - update the block_group and space info counters
2989 * @cache: The cache we are manipulating
2990 * @num_bytes: The number of bytes in question
2991 * @delalloc: The blocks are allocated for the delalloc write
2993 * This is called by somebody who is freeing space that was never actually used
2994 * on disk. For example if you reserve some space for a new leaf in transaction
2995 * A and before transaction A commits you free that leaf, you call this with
2996 * reserve set to 0 in order to clear the reservation.
2998 void btrfs_free_reserved_bytes(struct btrfs_block_group
*cache
,
2999 u64 num_bytes
, int delalloc
)
3001 struct btrfs_space_info
*space_info
= cache
->space_info
;
3003 spin_lock(&space_info
->lock
);
3004 spin_lock(&cache
->lock
);
3006 space_info
->bytes_readonly
+= num_bytes
;
3007 cache
->reserved
-= num_bytes
;
3008 space_info
->bytes_reserved
-= num_bytes
;
3009 space_info
->max_extent_size
= 0;
3012 cache
->delalloc_bytes
-= num_bytes
;
3013 spin_unlock(&cache
->lock
);
3014 spin_unlock(&space_info
->lock
);
3017 static void force_metadata_allocation(struct btrfs_fs_info
*info
)
3019 struct list_head
*head
= &info
->space_info
;
3020 struct btrfs_space_info
*found
;
3023 list_for_each_entry_rcu(found
, head
, list
) {
3024 if (found
->flags
& BTRFS_BLOCK_GROUP_METADATA
)
3025 found
->force_alloc
= CHUNK_ALLOC_FORCE
;
3030 static int should_alloc_chunk(struct btrfs_fs_info
*fs_info
,
3031 struct btrfs_space_info
*sinfo
, int force
)
3033 u64 bytes_used
= btrfs_space_info_used(sinfo
, false);
3036 if (force
== CHUNK_ALLOC_FORCE
)
3040 * in limited mode, we want to have some free space up to
3041 * about 1% of the FS size.
3043 if (force
== CHUNK_ALLOC_LIMITED
) {
3044 thresh
= btrfs_super_total_bytes(fs_info
->super_copy
);
3045 thresh
= max_t(u64
, SZ_64M
, div_factor_fine(thresh
, 1));
3047 if (sinfo
->total_bytes
- bytes_used
< thresh
)
3051 if (bytes_used
+ SZ_2M
< div_factor(sinfo
->total_bytes
, 8))
3056 int btrfs_force_chunk_alloc(struct btrfs_trans_handle
*trans
, u64 type
)
3058 u64 alloc_flags
= btrfs_get_alloc_profile(trans
->fs_info
, type
);
3060 return btrfs_chunk_alloc(trans
, alloc_flags
, CHUNK_ALLOC_FORCE
);
3064 * If force is CHUNK_ALLOC_FORCE:
3065 * - return 1 if it successfully allocates a chunk,
3066 * - return errors including -ENOSPC otherwise.
3067 * If force is NOT CHUNK_ALLOC_FORCE:
3068 * - return 0 if it doesn't need to allocate a new chunk,
3069 * - return 1 if it successfully allocates a chunk,
3070 * - return errors including -ENOSPC otherwise.
3072 int btrfs_chunk_alloc(struct btrfs_trans_handle
*trans
, u64 flags
,
3073 enum btrfs_chunk_alloc_enum force
)
3075 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
3076 struct btrfs_space_info
*space_info
;
3077 bool wait_for_alloc
= false;
3078 bool should_alloc
= false;
3081 /* Don't re-enter if we're already allocating a chunk */
3082 if (trans
->allocating_chunk
)
3085 space_info
= btrfs_find_space_info(fs_info
, flags
);
3089 spin_lock(&space_info
->lock
);
3090 if (force
< space_info
->force_alloc
)
3091 force
= space_info
->force_alloc
;
3092 should_alloc
= should_alloc_chunk(fs_info
, space_info
, force
);
3093 if (space_info
->full
) {
3094 /* No more free physical space */
3099 spin_unlock(&space_info
->lock
);
3101 } else if (!should_alloc
) {
3102 spin_unlock(&space_info
->lock
);
3104 } else if (space_info
->chunk_alloc
) {
3106 * Someone is already allocating, so we need to block
3107 * until this someone is finished and then loop to
3108 * recheck if we should continue with our allocation
3111 wait_for_alloc
= true;
3112 spin_unlock(&space_info
->lock
);
3113 mutex_lock(&fs_info
->chunk_mutex
);
3114 mutex_unlock(&fs_info
->chunk_mutex
);
3116 /* Proceed with allocation */
3117 space_info
->chunk_alloc
= 1;
3118 wait_for_alloc
= false;
3119 spin_unlock(&space_info
->lock
);
3123 } while (wait_for_alloc
);
3125 mutex_lock(&fs_info
->chunk_mutex
);
3126 trans
->allocating_chunk
= true;
3129 * If we have mixed data/metadata chunks we want to make sure we keep
3130 * allocating mixed chunks instead of individual chunks.
3132 if (btrfs_mixed_space_info(space_info
))
3133 flags
|= (BTRFS_BLOCK_GROUP_DATA
| BTRFS_BLOCK_GROUP_METADATA
);
3136 * if we're doing a data chunk, go ahead and make sure that
3137 * we keep a reasonable number of metadata chunks allocated in the
3140 if (flags
& BTRFS_BLOCK_GROUP_DATA
&& fs_info
->metadata_ratio
) {
3141 fs_info
->data_chunk_allocations
++;
3142 if (!(fs_info
->data_chunk_allocations
%
3143 fs_info
->metadata_ratio
))
3144 force_metadata_allocation(fs_info
);
3148 * Check if we have enough space in SYSTEM chunk because we may need
3149 * to update devices.
3151 check_system_chunk(trans
, flags
);
3153 ret
= btrfs_alloc_chunk(trans
, flags
);
3154 trans
->allocating_chunk
= false;
3156 spin_lock(&space_info
->lock
);
3159 space_info
->full
= 1;
3164 space_info
->max_extent_size
= 0;
3167 space_info
->force_alloc
= CHUNK_ALLOC_NO_FORCE
;
3169 space_info
->chunk_alloc
= 0;
3170 spin_unlock(&space_info
->lock
);
3171 mutex_unlock(&fs_info
->chunk_mutex
);
3173 * When we allocate a new chunk we reserve space in the chunk block
3174 * reserve to make sure we can COW nodes/leafs in the chunk tree or
3175 * add new nodes/leafs to it if we end up needing to do it when
3176 * inserting the chunk item and updating device items as part of the
3177 * second phase of chunk allocation, performed by
3178 * btrfs_finish_chunk_alloc(). So make sure we don't accumulate a
3179 * large number of new block groups to create in our transaction
3180 * handle's new_bgs list to avoid exhausting the chunk block reserve
3181 * in extreme cases - like having a single transaction create many new
3182 * block groups when starting to write out the free space caches of all
3183 * the block groups that were made dirty during the lifetime of the
3186 if (trans
->chunk_bytes_reserved
>= (u64
)SZ_2M
)
3187 btrfs_create_pending_block_groups(trans
);
3192 static u64
get_profile_num_devs(struct btrfs_fs_info
*fs_info
, u64 type
)
3196 num_dev
= btrfs_raid_array
[btrfs_bg_flags_to_raid_index(type
)].devs_max
;
3198 num_dev
= fs_info
->fs_devices
->rw_devices
;
3204 * Reserve space in the system space for allocating or removing a chunk
3206 void check_system_chunk(struct btrfs_trans_handle
*trans
, u64 type
)
3208 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
3209 struct btrfs_space_info
*info
;
3216 * Needed because we can end up allocating a system chunk and for an
3217 * atomic and race free space reservation in the chunk block reserve.
3219 lockdep_assert_held(&fs_info
->chunk_mutex
);
3221 info
= btrfs_find_space_info(fs_info
, BTRFS_BLOCK_GROUP_SYSTEM
);
3222 spin_lock(&info
->lock
);
3223 left
= info
->total_bytes
- btrfs_space_info_used(info
, true);
3224 spin_unlock(&info
->lock
);
3226 num_devs
= get_profile_num_devs(fs_info
, type
);
3228 /* num_devs device items to update and 1 chunk item to add or remove */
3229 thresh
= btrfs_calc_metadata_size(fs_info
, num_devs
) +
3230 btrfs_calc_insert_metadata_size(fs_info
, 1);
3232 if (left
< thresh
&& btrfs_test_opt(fs_info
, ENOSPC_DEBUG
)) {
3233 btrfs_info(fs_info
, "left=%llu, need=%llu, flags=%llu",
3234 left
, thresh
, type
);
3235 btrfs_dump_space_info(fs_info
, info
, 0, 0);
3238 if (left
< thresh
) {
3239 u64 flags
= btrfs_system_alloc_profile(fs_info
);
3242 * Ignore failure to create system chunk. We might end up not
3243 * needing it, as we might not need to COW all nodes/leafs from
3244 * the paths we visit in the chunk tree (they were already COWed
3245 * or created in the current transaction for example).
3247 ret
= btrfs_alloc_chunk(trans
, flags
);
3251 ret
= btrfs_block_rsv_add(fs_info
->chunk_root
,
3252 &fs_info
->chunk_block_rsv
,
3253 thresh
, BTRFS_RESERVE_NO_FLUSH
);
3255 trans
->chunk_bytes_reserved
+= thresh
;
3259 void btrfs_put_block_group_cache(struct btrfs_fs_info
*info
)
3261 struct btrfs_block_group
*block_group
;
3265 struct inode
*inode
;
3267 block_group
= btrfs_lookup_first_block_group(info
, last
);
3268 while (block_group
) {
3269 btrfs_wait_block_group_cache_done(block_group
);
3270 spin_lock(&block_group
->lock
);
3271 if (block_group
->iref
)
3273 spin_unlock(&block_group
->lock
);
3274 block_group
= btrfs_next_block_group(block_group
);
3283 inode
= block_group
->inode
;
3284 block_group
->iref
= 0;
3285 block_group
->inode
= NULL
;
3286 spin_unlock(&block_group
->lock
);
3287 ASSERT(block_group
->io_ctl
.inode
== NULL
);
3289 last
= block_group
->start
+ block_group
->length
;
3290 btrfs_put_block_group(block_group
);
3295 * Must be called only after stopping all workers, since we could have block
3296 * group caching kthreads running, and therefore they could race with us if we
3297 * freed the block groups before stopping them.
3299 int btrfs_free_block_groups(struct btrfs_fs_info
*info
)
3301 struct btrfs_block_group
*block_group
;
3302 struct btrfs_space_info
*space_info
;
3303 struct btrfs_caching_control
*caching_ctl
;
3306 down_write(&info
->commit_root_sem
);
3307 while (!list_empty(&info
->caching_block_groups
)) {
3308 caching_ctl
= list_entry(info
->caching_block_groups
.next
,
3309 struct btrfs_caching_control
, list
);
3310 list_del(&caching_ctl
->list
);
3311 btrfs_put_caching_control(caching_ctl
);
3313 up_write(&info
->commit_root_sem
);
3315 spin_lock(&info
->unused_bgs_lock
);
3316 while (!list_empty(&info
->unused_bgs
)) {
3317 block_group
= list_first_entry(&info
->unused_bgs
,
3318 struct btrfs_block_group
,
3320 list_del_init(&block_group
->bg_list
);
3321 btrfs_put_block_group(block_group
);
3323 spin_unlock(&info
->unused_bgs_lock
);
3325 spin_lock(&info
->block_group_cache_lock
);
3326 while ((n
= rb_last(&info
->block_group_cache_tree
)) != NULL
) {
3327 block_group
= rb_entry(n
, struct btrfs_block_group
,
3329 rb_erase(&block_group
->cache_node
,
3330 &info
->block_group_cache_tree
);
3331 RB_CLEAR_NODE(&block_group
->cache_node
);
3332 spin_unlock(&info
->block_group_cache_lock
);
3334 down_write(&block_group
->space_info
->groups_sem
);
3335 list_del(&block_group
->list
);
3336 up_write(&block_group
->space_info
->groups_sem
);
3339 * We haven't cached this block group, which means we could
3340 * possibly have excluded extents on this block group.
3342 if (block_group
->cached
== BTRFS_CACHE_NO
||
3343 block_group
->cached
== BTRFS_CACHE_ERROR
)
3344 btrfs_free_excluded_extents(block_group
);
3346 btrfs_remove_free_space_cache(block_group
);
3347 ASSERT(block_group
->cached
!= BTRFS_CACHE_STARTED
);
3348 ASSERT(list_empty(&block_group
->dirty_list
));
3349 ASSERT(list_empty(&block_group
->io_list
));
3350 ASSERT(list_empty(&block_group
->bg_list
));
3351 ASSERT(atomic_read(&block_group
->count
) == 1);
3352 btrfs_put_block_group(block_group
);
3354 spin_lock(&info
->block_group_cache_lock
);
3356 spin_unlock(&info
->block_group_cache_lock
);
3359 * Now that all the block groups are freed, go through and free all the
3360 * space_info structs. This is only called during the final stages of
3361 * unmount, and so we know nobody is using them. We call
3362 * synchronize_rcu() once before we start, just to be on the safe side.
3366 btrfs_release_global_block_rsv(info
);
3368 while (!list_empty(&info
->space_info
)) {
3369 space_info
= list_entry(info
->space_info
.next
,
3370 struct btrfs_space_info
,
3374 * Do not hide this behind enospc_debug, this is actually
3375 * important and indicates a real bug if this happens.
3377 if (WARN_ON(space_info
->bytes_pinned
> 0 ||
3378 space_info
->bytes_reserved
> 0 ||
3379 space_info
->bytes_may_use
> 0))
3380 btrfs_dump_space_info(info
, space_info
, 0, 0);
3381 WARN_ON(space_info
->reclaim_size
> 0);
3382 list_del(&space_info
->list
);
3383 btrfs_sysfs_remove_space_info(space_info
);