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->pinned_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 btrfs_put_block_group(block_group);
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 btrfs_delayed_refs_rsv_release(fs_info, 1);
1133 btrfs_free_path(path);
1137 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
1138 struct btrfs_fs_info *fs_info, const u64 chunk_offset)
1140 struct extent_map_tree *em_tree = &fs_info->mapping_tree;
1141 struct extent_map *em;
1142 struct map_lookup *map;
1143 unsigned int num_items;
1145 read_lock(&em_tree->lock);
1146 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
1147 read_unlock(&em_tree->lock);
1148 ASSERT(em && em->start == chunk_offset);
1151 * We need to reserve 3 + N units from the metadata space info in order
1152 * to remove a block group (done at btrfs_remove_chunk() and at
1153 * btrfs_remove_block_group()), which are used for:
1155 * 1 unit for adding the free space inode's orphan (located in the tree
1157 * 1 unit for deleting the block group item (located in the extent
1159 * 1 unit for deleting the free space item (located in tree of tree
1161 * N units for deleting N device extent items corresponding to each
1162 * stripe (located in the device tree).
1164 * In order to remove a block group we also need to reserve units in the
1165 * system space info in order to update the chunk tree (update one or
1166 * more device items and remove one chunk item), but this is done at
1167 * btrfs_remove_chunk() through a call to check_system_chunk().
1169 map = em->map_lookup;
1170 num_items = 3 + map->num_stripes;
1171 free_extent_map(em);
1173 return btrfs_start_transaction_fallback_global_rsv(fs_info->extent_root,
1178 * Mark block group @cache read-only, so later write won't happen to block
1181 * If @force is not set, this function will only mark the block group readonly
1182 * if we have enough free space (1M) in other metadata/system block groups.
1183 * If @force is not set, this function will mark the block group readonly
1184 * without checking free space.
1186 * NOTE: This function doesn't care if other block groups can contain all the
1187 * data in this block group. That check should be done by relocation routine,
1188 * not this function.
1190 static int inc_block_group_ro(struct btrfs_block_group *cache, int force)
1192 struct btrfs_space_info *sinfo = cache->space_info;
1197 spin_lock(&sinfo->lock);
1198 spin_lock(&cache->lock);
1206 num_bytes = cache->length - cache->reserved - cache->pinned -
1207 cache->bytes_super - cache->used;
1208 sinfo_used = btrfs_space_info_used(sinfo, true);
1211 * sinfo_used + num_bytes should always <= sinfo->total_bytes.
1213 * Here we make sure if we mark this bg RO, we still have enough
1214 * free space as buffer.
1216 if (sinfo_used + num_bytes <= sinfo->total_bytes) {
1217 sinfo->bytes_readonly += num_bytes;
1219 list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
1223 spin_unlock(&cache->lock);
1224 spin_unlock(&sinfo->lock);
1225 if (ret == -ENOSPC && btrfs_test_opt(cache->fs_info, ENOSPC_DEBUG)) {
1226 btrfs_info(cache->fs_info,
1227 "unable to make block group %llu ro", cache->start);
1228 btrfs_info(cache->fs_info,
1229 "sinfo_used=%llu bg_num_bytes=%llu",
1230 sinfo_used, num_bytes);
1231 btrfs_dump_space_info(cache->fs_info, cache->space_info, 0, 0);
1237 * Process the unused_bgs list and remove any that don't have any allocated
1238 * space inside of them.
1240 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
1242 struct btrfs_block_group *block_group;
1243 struct btrfs_space_info *space_info;
1244 struct btrfs_trans_handle *trans;
1245 const bool async_trim_enabled = btrfs_test_opt(fs_info, DISCARD_ASYNC);
1248 if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1251 spin_lock(&fs_info->unused_bgs_lock);
1252 while (!list_empty(&fs_info->unused_bgs)) {
1256 block_group = list_first_entry(&fs_info->unused_bgs,
1257 struct btrfs_block_group,
1259 list_del_init(&block_group->bg_list);
1261 space_info = block_group->space_info;
1263 if (ret || btrfs_mixed_space_info(space_info)) {
1264 btrfs_put_block_group(block_group);
1267 spin_unlock(&fs_info->unused_bgs_lock);
1269 btrfs_discard_cancel_work(&fs_info->discard_ctl, block_group);
1271 mutex_lock(&fs_info->delete_unused_bgs_mutex);
1273 /* Don't want to race with allocators so take the groups_sem */
1274 down_write(&space_info->groups_sem);
1277 * Async discard moves the final block group discard to be prior
1278 * to the unused_bgs code path. Therefore, if it's not fully
1279 * trimmed, punt it back to the async discard lists.
1281 if (btrfs_test_opt(fs_info, DISCARD_ASYNC) &&
1282 !btrfs_is_free_space_trimmed(block_group)) {
1283 trace_btrfs_skip_unused_block_group(block_group);
1284 up_write(&space_info->groups_sem);
1285 /* Requeue if we failed because of async discard */
1286 btrfs_discard_queue_work(&fs_info->discard_ctl,
1291 spin_lock(&block_group->lock);
1292 if (block_group->reserved || block_group->pinned ||
1293 block_group->used || block_group->ro ||
1294 list_is_singular(&block_group->list)) {
1296 * We want to bail if we made new allocations or have
1297 * outstanding allocations in this block group. We do
1298 * the ro check in case balance is currently acting on
1301 trace_btrfs_skip_unused_block_group(block_group);
1302 spin_unlock(&block_group->lock);
1303 up_write(&space_info->groups_sem);
1306 spin_unlock(&block_group->lock);
1308 /* We don't want to force the issue, only flip if it's ok. */
1309 ret = inc_block_group_ro(block_group, 0);
1310 up_write(&space_info->groups_sem);
1317 * Want to do this before we do anything else so we can recover
1318 * properly if we fail to join the transaction.
1320 trans = btrfs_start_trans_remove_block_group(fs_info,
1321 block_group->start);
1322 if (IS_ERR(trans)) {
1323 btrfs_dec_block_group_ro(block_group);
1324 ret = PTR_ERR(trans);
1329 * We could have pending pinned extents for this block group,
1330 * just delete them, we don't care about them anymore.
1332 start = block_group->start;
1333 end = start + block_group->length - 1;
1335 * Hold the unused_bg_unpin_mutex lock to avoid racing with
1336 * btrfs_finish_extent_commit(). If we are at transaction N,
1337 * another task might be running finish_extent_commit() for the
1338 * previous transaction N - 1, and have seen a range belonging
1339 * to the block group in freed_extents[] before we were able to
1340 * clear the whole block group range from freed_extents[]. This
1341 * means that task can lookup for the block group after we
1342 * unpinned it from freed_extents[] and removed it, leading to
1343 * a BUG_ON() at btrfs_unpin_extent_range().
1345 mutex_lock(&fs_info->unused_bg_unpin_mutex);
1346 ret = clear_extent_bits(&fs_info->freed_extents[0], start, end,
1349 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
1350 btrfs_dec_block_group_ro(block_group);
1353 ret = clear_extent_bits(&fs_info->freed_extents[1], start, end,
1356 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
1357 btrfs_dec_block_group_ro(block_group);
1360 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
1363 * At this point, the block_group is read only and should fail
1364 * new allocations. However, btrfs_finish_extent_commit() can
1365 * cause this block_group to be placed back on the discard
1366 * lists because now the block_group isn't fully discarded.
1367 * Bail here and try again later after discarding everything.
1369 spin_lock(&fs_info->discard_ctl.lock);
1370 if (!list_empty(&block_group->discard_list)) {
1371 spin_unlock(&fs_info->discard_ctl.lock);
1372 btrfs_dec_block_group_ro(block_group);
1373 btrfs_discard_queue_work(&fs_info->discard_ctl,
1377 spin_unlock(&fs_info->discard_ctl.lock);
1379 /* Reset pinned so btrfs_put_block_group doesn't complain */
1380 spin_lock(&space_info->lock);
1381 spin_lock(&block_group->lock);
1383 btrfs_space_info_update_bytes_pinned(fs_info, space_info,
1384 -block_group->pinned);
1385 space_info->bytes_readonly += block_group->pinned;
1386 percpu_counter_add_batch(&space_info->total_bytes_pinned,
1387 -block_group->pinned,
1388 BTRFS_TOTAL_BYTES_PINNED_BATCH);
1389 block_group->pinned = 0;
1391 spin_unlock(&block_group->lock);
1392 spin_unlock(&space_info->lock);
1395 * The normal path here is an unused block group is passed here,
1396 * then trimming is handled in the transaction commit path.
1397 * Async discard interposes before this to do the trimming
1398 * before coming down the unused block group path as trimming
1399 * will no longer be done later in the transaction commit path.
1401 if (!async_trim_enabled && btrfs_test_opt(fs_info, DISCARD_ASYNC))
1404 /* DISCARD can flip during remount */
1405 trimming = btrfs_test_opt(fs_info, DISCARD_SYNC);
1407 /* Implicit trim during transaction commit. */
1409 btrfs_get_block_group_trimming(block_group);
1412 * Btrfs_remove_chunk will abort the transaction if things go
1415 ret = btrfs_remove_chunk(trans, block_group->start);
1419 btrfs_put_block_group_trimming(block_group);
1424 * If we're not mounted with -odiscard, we can just forget
1425 * about this block group. Otherwise we'll need to wait
1426 * until transaction commit to do the actual discard.
1429 spin_lock(&fs_info->unused_bgs_lock);
1431 * A concurrent scrub might have added us to the list
1432 * fs_info->unused_bgs, so use a list_move operation
1433 * to add the block group to the deleted_bgs list.
1435 list_move(&block_group->bg_list,
1436 &trans->transaction->deleted_bgs);
1437 spin_unlock(&fs_info->unused_bgs_lock);
1438 btrfs_get_block_group(block_group);
1441 btrfs_end_transaction(trans);
1443 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
1444 btrfs_put_block_group(block_group);
1445 spin_lock(&fs_info->unused_bgs_lock);
1447 spin_unlock(&fs_info->unused_bgs_lock);
1451 btrfs_end_transaction(trans);
1452 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
1453 btrfs_put_block_group(block_group);
1454 btrfs_discard_punt_unused_bgs_list(fs_info);
1457 void btrfs_mark_bg_unused(struct btrfs_block_group *bg)
1459 struct btrfs_fs_info *fs_info = bg->fs_info;
1461 spin_lock(&fs_info->unused_bgs_lock);
1462 if (list_empty(&bg->bg_list)) {
1463 btrfs_get_block_group(bg);
1464 trace_btrfs_add_unused_block_group(bg);
1465 list_add_tail(&bg->bg_list, &fs_info->unused_bgs);
1467 spin_unlock(&fs_info->unused_bgs_lock);
1470 static int find_first_block_group(struct btrfs_fs_info *fs_info,
1471 struct btrfs_path *path,
1472 struct btrfs_key *key)
1474 struct btrfs_root *root = fs_info->extent_root;
1476 struct btrfs_key found_key;
1477 struct extent_buffer *leaf;
1478 struct btrfs_block_group_item bg;
1482 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
1487 slot = path->slots[0];
1488 leaf = path->nodes[0];
1489 if (slot >= btrfs_header_nritems(leaf)) {
1490 ret = btrfs_next_leaf(root, path);
1497 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1499 if (found_key.objectid >= key->objectid &&
1500 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
1501 struct extent_map_tree *em_tree;
1502 struct extent_map *em;
1504 em_tree = &root->fs_info->mapping_tree;
1505 read_lock(&em_tree->lock);
1506 em = lookup_extent_mapping(em_tree, found_key.objectid,
1508 read_unlock(&em_tree->lock);
1511 "logical %llu len %llu found bg but no related chunk",
1512 found_key.objectid, found_key.offset);
1514 } else if (em->start != found_key.objectid ||
1515 em->len != found_key.offset) {
1517 "block group %llu len %llu mismatch with chunk %llu len %llu",
1518 found_key.objectid, found_key.offset,
1519 em->start, em->len);
1522 read_extent_buffer(leaf, &bg,
1523 btrfs_item_ptr_offset(leaf, slot),
1525 flags = btrfs_stack_block_group_flags(&bg) &
1526 BTRFS_BLOCK_GROUP_TYPE_MASK;
1528 if (flags != (em->map_lookup->type &
1529 BTRFS_BLOCK_GROUP_TYPE_MASK)) {
1531 "block group %llu len %llu type flags 0x%llx mismatch with chunk type flags 0x%llx",
1533 found_key.offset, flags,
1534 (BTRFS_BLOCK_GROUP_TYPE_MASK &
1535 em->map_lookup->type));
1541 free_extent_map(em);
1550 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
1552 u64 extra_flags = chunk_to_extended(flags) &
1553 BTRFS_EXTENDED_PROFILE_MASK;
1555 write_seqlock(&fs_info->profiles_lock);
1556 if (flags & BTRFS_BLOCK_GROUP_DATA)
1557 fs_info->avail_data_alloc_bits |= extra_flags;
1558 if (flags & BTRFS_BLOCK_GROUP_METADATA)
1559 fs_info->avail_metadata_alloc_bits |= extra_flags;
1560 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
1561 fs_info->avail_system_alloc_bits |= extra_flags;
1562 write_sequnlock(&fs_info->profiles_lock);
1566 * btrfs_rmap_block - Map a physical disk address to a list of logical addresses
1567 * @chunk_start: logical address of block group
1568 * @physical: physical address to map to logical addresses
1569 * @logical: return array of logical addresses which map to @physical
1570 * @naddrs: length of @logical
1571 * @stripe_len: size of IO stripe for the given block group
1573 * Maps a particular @physical disk address to a list of @logical addresses.
1574 * Used primarily to exclude those portions of a block group that contain super
1578 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
1579 u64 physical, u64 **logical, int *naddrs, int *stripe_len)
1581 struct extent_map *em;
1582 struct map_lookup *map;
1585 u64 data_stripe_length;
1590 em = btrfs_get_chunk_map(fs_info, chunk_start, 1);
1594 map = em->map_lookup;
1595 data_stripe_length = em->len;
1596 io_stripe_size = map->stripe_len;
1598 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
1599 data_stripe_length = div_u64(data_stripe_length,
1600 map->num_stripes / map->sub_stripes);
1601 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
1602 data_stripe_length = div_u64(data_stripe_length, map->num_stripes);
1603 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
1604 data_stripe_length = div_u64(data_stripe_length,
1605 nr_data_stripes(map));
1606 io_stripe_size = map->stripe_len * nr_data_stripes(map);
1609 buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
1615 for (i = 0; i < map->num_stripes; i++) {
1616 bool already_inserted = false;
1620 if (!in_range(physical, map->stripes[i].physical,
1621 data_stripe_length))
1624 stripe_nr = physical - map->stripes[i].physical;
1625 stripe_nr = div64_u64(stripe_nr, map->stripe_len);
1627 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
1628 stripe_nr = stripe_nr * map->num_stripes + i;
1629 stripe_nr = div_u64(stripe_nr, map->sub_stripes);
1630 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
1631 stripe_nr = stripe_nr * map->num_stripes + i;
1634 * The remaining case would be for RAID56, multiply by
1635 * nr_data_stripes(). Alternatively, just use rmap_len below
1636 * instead of map->stripe_len
1639 bytenr = chunk_start + stripe_nr * io_stripe_size;
1641 /* Ensure we don't add duplicate addresses */
1642 for (j = 0; j < nr; j++) {
1643 if (buf[j] == bytenr) {
1644 already_inserted = true;
1649 if (!already_inserted)
1655 *stripe_len = io_stripe_size;
1657 free_extent_map(em);
1661 static int exclude_super_stripes(struct btrfs_block_group *cache)
1663 struct btrfs_fs_info *fs_info = cache->fs_info;
1669 if (cache->start < BTRFS_SUPER_INFO_OFFSET) {
1670 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->start;
1671 cache->bytes_super += stripe_len;
1672 ret = btrfs_add_excluded_extent(fs_info, cache->start,
1678 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1679 bytenr = btrfs_sb_offset(i);
1680 ret = btrfs_rmap_block(fs_info, cache->start,
1681 bytenr, &logical, &nr, &stripe_len);
1688 if (logical[nr] > cache->start + cache->length)
1691 if (logical[nr] + stripe_len <= cache->start)
1694 start = logical[nr];
1695 if (start < cache->start) {
1696 start = cache->start;
1697 len = (logical[nr] + stripe_len) - start;
1699 len = min_t(u64, stripe_len,
1700 cache->start + cache->length - start);
1703 cache->bytes_super += len;
1704 ret = btrfs_add_excluded_extent(fs_info, start, len);
1716 static void link_block_group(struct btrfs_block_group *cache)
1718 struct btrfs_space_info *space_info = cache->space_info;
1719 int index = btrfs_bg_flags_to_raid_index(cache->flags);
1722 down_write(&space_info->groups_sem);
1723 if (list_empty(&space_info->block_groups[index]))
1725 list_add_tail(&cache->list, &space_info->block_groups[index]);
1726 up_write(&space_info->groups_sem);
1729 btrfs_sysfs_add_block_group_type(cache);
1732 static struct btrfs_block_group *btrfs_create_block_group_cache(
1733 struct btrfs_fs_info *fs_info, u64 start, u64 size)
1735 struct btrfs_block_group *cache;
1737 cache = kzalloc(sizeof(*cache), GFP_NOFS);
1741 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
1743 if (!cache->free_space_ctl) {
1748 cache->start = start;
1749 cache->length = size;
1751 cache->fs_info = fs_info;
1752 cache->full_stripe_len = btrfs_full_stripe_len(fs_info, start);
1753 set_free_space_tree_thresholds(cache);
1755 cache->discard_index = BTRFS_DISCARD_INDEX_UNUSED;
1757 atomic_set(&cache->count, 1);
1758 spin_lock_init(&cache->lock);
1759 init_rwsem(&cache->data_rwsem);
1760 INIT_LIST_HEAD(&cache->list);
1761 INIT_LIST_HEAD(&cache->cluster_list);
1762 INIT_LIST_HEAD(&cache->bg_list);
1763 INIT_LIST_HEAD(&cache->ro_list);
1764 INIT_LIST_HEAD(&cache->discard_list);
1765 INIT_LIST_HEAD(&cache->dirty_list);
1766 INIT_LIST_HEAD(&cache->io_list);
1767 btrfs_init_free_space_ctl(cache);
1768 atomic_set(&cache->trimming, 0);
1769 mutex_init(&cache->free_space_lock);
1770 btrfs_init_full_stripe_locks_tree(&cache->full_stripe_locks_root);
1776 * Iterate all chunks and verify that each of them has the corresponding block
1779 static int check_chunk_block_group_mappings(struct btrfs_fs_info *fs_info)
1781 struct extent_map_tree *map_tree = &fs_info->mapping_tree;
1782 struct extent_map *em;
1783 struct btrfs_block_group *bg;
1788 read_lock(&map_tree->lock);
1790 * lookup_extent_mapping will return the first extent map
1791 * intersecting the range, so setting @len to 1 is enough to
1792 * get the first chunk.
1794 em = lookup_extent_mapping(map_tree, start, 1);
1795 read_unlock(&map_tree->lock);
1799 bg = btrfs_lookup_block_group(fs_info, em->start);
1802 "chunk start=%llu len=%llu doesn't have corresponding block group",
1803 em->start, em->len);
1805 free_extent_map(em);
1808 if (bg->start != em->start || bg->length != em->len ||
1809 (bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK) !=
1810 (em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
1812 "chunk start=%llu len=%llu flags=0x%llx doesn't match block group start=%llu len=%llu flags=0x%llx",
1814 em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK,
1815 bg->start, bg->length,
1816 bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK);
1818 free_extent_map(em);
1819 btrfs_put_block_group(bg);
1822 start = em->start + em->len;
1823 free_extent_map(em);
1824 btrfs_put_block_group(bg);
1829 static int read_one_block_group(struct btrfs_fs_info *info,
1830 struct btrfs_path *path,
1831 const struct btrfs_key *key,
1834 struct extent_buffer *leaf = path->nodes[0];
1835 struct btrfs_block_group *cache;
1836 struct btrfs_space_info *space_info;
1837 struct btrfs_block_group_item bgi;
1838 const bool mixed = btrfs_fs_incompat(info, MIXED_GROUPS);
1839 int slot = path->slots[0];
1842 ASSERT(key->type == BTRFS_BLOCK_GROUP_ITEM_KEY);
1844 cache = btrfs_create_block_group_cache(info, key->objectid, key->offset);
1850 * When we mount with old space cache, we need to
1851 * set BTRFS_DC_CLEAR and set dirty flag.
1853 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
1854 * truncate the old free space cache inode and
1856 * b) Setting 'dirty flag' makes sure that we flush
1857 * the new space cache info onto disk.
1859 if (btrfs_test_opt(info, SPACE_CACHE))
1860 cache->disk_cache_state = BTRFS_DC_CLEAR;
1862 read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
1864 cache->used = btrfs_stack_block_group_used(&bgi);
1865 cache->flags = btrfs_stack_block_group_flags(&bgi);
1866 if (!mixed && ((cache->flags & BTRFS_BLOCK_GROUP_METADATA) &&
1867 (cache->flags & BTRFS_BLOCK_GROUP_DATA))) {
1869 "bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups",
1876 * We need to exclude the super stripes now so that the space info has
1877 * super bytes accounted for, otherwise we'll think we have more space
1878 * than we actually do.
1880 ret = exclude_super_stripes(cache);
1882 /* We may have excluded something, so call this just in case. */
1883 btrfs_free_excluded_extents(cache);
1888 * Check for two cases, either we are full, and therefore don't need
1889 * to bother with the caching work since we won't find any space, or we
1890 * are empty, and we can just add all the space in and be done with it.
1891 * This saves us _a_lot_ of time, particularly in the full case.
1893 if (key->offset == cache->used) {
1894 cache->last_byte_to_unpin = (u64)-1;
1895 cache->cached = BTRFS_CACHE_FINISHED;
1896 btrfs_free_excluded_extents(cache);
1897 } else if (cache->used == 0) {
1898 cache->last_byte_to_unpin = (u64)-1;
1899 cache->cached = BTRFS_CACHE_FINISHED;
1900 add_new_free_space(cache, key->objectid,
1901 key->objectid + key->offset);
1902 btrfs_free_excluded_extents(cache);
1905 ret = btrfs_add_block_group_cache(info, cache);
1907 btrfs_remove_free_space_cache(cache);
1910 trace_btrfs_add_block_group(info, cache, 0);
1911 btrfs_update_space_info(info, cache->flags, key->offset,
1912 cache->used, cache->bytes_super, &space_info);
1914 cache->space_info = space_info;
1916 link_block_group(cache);
1918 set_avail_alloc_bits(info, cache->flags);
1919 if (btrfs_chunk_readonly(info, cache->start)) {
1920 inc_block_group_ro(cache, 1);
1921 } else if (cache->used == 0) {
1922 ASSERT(list_empty(&cache->bg_list));
1923 if (btrfs_test_opt(info, DISCARD_ASYNC))
1924 btrfs_discard_queue_work(&info->discard_ctl, cache);
1926 btrfs_mark_bg_unused(cache);
1930 btrfs_put_block_group(cache);
1934 int btrfs_read_block_groups(struct btrfs_fs_info *info)
1936 struct btrfs_path *path;
1938 struct btrfs_block_group *cache;
1939 struct btrfs_space_info *space_info;
1940 struct btrfs_key key;
1946 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
1947 path = btrfs_alloc_path();
1950 path->reada = READA_FORWARD;
1952 cache_gen = btrfs_super_cache_generation(info->super_copy);
1953 if (btrfs_test_opt(info, SPACE_CACHE) &&
1954 btrfs_super_generation(info->super_copy) != cache_gen)
1956 if (btrfs_test_opt(info, CLEAR_CACHE))
1960 ret = find_first_block_group(info, path, &key);
1966 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1967 ret = read_one_block_group(info, path, &key, need_clear);
1970 key.objectid += key.offset;
1972 btrfs_release_path(path);
1975 list_for_each_entry_rcu(space_info, &info->space_info, list) {
1976 if (!(btrfs_get_alloc_profile(info, space_info->flags) &
1977 (BTRFS_BLOCK_GROUP_RAID10 |
1978 BTRFS_BLOCK_GROUP_RAID1_MASK |
1979 BTRFS_BLOCK_GROUP_RAID56_MASK |
1980 BTRFS_BLOCK_GROUP_DUP)))
1983 * Avoid allocating from un-mirrored block group if there are
1984 * mirrored block groups.
1986 list_for_each_entry(cache,
1987 &space_info->block_groups[BTRFS_RAID_RAID0],
1989 inc_block_group_ro(cache, 1);
1990 list_for_each_entry(cache,
1991 &space_info->block_groups[BTRFS_RAID_SINGLE],
1993 inc_block_group_ro(cache, 1);
1996 btrfs_init_global_block_rsv(info);
1997 ret = check_chunk_block_group_mappings(info);
1999 btrfs_free_path(path);
2003 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
2005 struct btrfs_fs_info *fs_info = trans->fs_info;
2006 struct btrfs_block_group *block_group;
2007 struct btrfs_root *extent_root = fs_info->extent_root;
2008 struct btrfs_block_group_item item;
2009 struct btrfs_key key;
2012 if (!trans->can_flush_pending_bgs)
2015 while (!list_empty(&trans->new_bgs)) {
2016 block_group = list_first_entry(&trans->new_bgs,
2017 struct btrfs_block_group,
2022 spin_lock(&block_group->lock);
2023 btrfs_set_stack_block_group_used(&item, block_group->used);
2024 btrfs_set_stack_block_group_chunk_objectid(&item,
2025 BTRFS_FIRST_CHUNK_TREE_OBJECTID);
2026 btrfs_set_stack_block_group_flags(&item, block_group->flags);
2027 key.objectid = block_group->start;
2028 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
2029 key.offset = block_group->length;
2030 spin_unlock(&block_group->lock);
2032 ret = btrfs_insert_item(trans, extent_root, &key, &item,
2035 btrfs_abort_transaction(trans, ret);
2036 ret = btrfs_finish_chunk_alloc(trans, key.objectid, key.offset);
2038 btrfs_abort_transaction(trans, ret);
2039 add_block_group_free_space(trans, block_group);
2040 /* Already aborted the transaction if it failed. */
2042 btrfs_delayed_refs_rsv_release(fs_info, 1);
2043 list_del_init(&block_group->bg_list);
2045 btrfs_trans_release_chunk_metadata(trans);
2048 int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
2049 u64 type, u64 chunk_offset, u64 size)
2051 struct btrfs_fs_info *fs_info = trans->fs_info;
2052 struct btrfs_block_group *cache;
2055 btrfs_set_log_full_commit(trans);
2057 cache = btrfs_create_block_group_cache(fs_info, chunk_offset, size);
2061 cache->used = bytes_used;
2062 cache->flags = type;
2063 cache->last_byte_to_unpin = (u64)-1;
2064 cache->cached = BTRFS_CACHE_FINISHED;
2065 cache->needs_free_space = 1;
2066 ret = exclude_super_stripes(cache);
2068 /* We may have excluded something, so call this just in case */
2069 btrfs_free_excluded_extents(cache);
2070 btrfs_put_block_group(cache);
2074 add_new_free_space(cache, chunk_offset, chunk_offset + size);
2076 btrfs_free_excluded_extents(cache);
2078 #ifdef CONFIG_BTRFS_DEBUG
2079 if (btrfs_should_fragment_free_space(cache)) {
2080 u64 new_bytes_used = size - bytes_used;
2082 bytes_used += new_bytes_used >> 1;
2083 fragment_free_space(cache);
2087 * Ensure the corresponding space_info object is created and
2088 * assigned to our block group. We want our bg to be added to the rbtree
2089 * with its ->space_info set.
2091 cache->space_info = btrfs_find_space_info(fs_info, cache->flags);
2092 ASSERT(cache->space_info);
2094 ret = btrfs_add_block_group_cache(fs_info, cache);
2096 btrfs_remove_free_space_cache(cache);
2097 btrfs_put_block_group(cache);
2102 * Now that our block group has its ->space_info set and is inserted in
2103 * the rbtree, update the space info's counters.
2105 trace_btrfs_add_block_group(fs_info, cache, 1);
2106 btrfs_update_space_info(fs_info, cache->flags, size, bytes_used,
2107 cache->bytes_super, &cache->space_info);
2108 btrfs_update_global_block_rsv(fs_info);
2110 link_block_group(cache);
2112 list_add_tail(&cache->bg_list, &trans->new_bgs);
2113 trans->delayed_ref_updates++;
2114 btrfs_update_delayed_refs_rsv(trans);
2116 set_avail_alloc_bits(fs_info, type);
2120 static u64 update_block_group_flags(struct btrfs_fs_info *fs_info, u64 flags)
2126 * if restripe for this chunk_type is on pick target profile and
2127 * return, otherwise do the usual balance
2129 stripped = get_restripe_target(fs_info, flags);
2131 return extended_to_chunk(stripped);
2133 num_devices = fs_info->fs_devices->rw_devices;
2135 stripped = BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID56_MASK |
2136 BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10;
2138 if (num_devices == 1) {
2139 stripped |= BTRFS_BLOCK_GROUP_DUP;
2140 stripped = flags & ~stripped;
2142 /* turn raid0 into single device chunks */
2143 if (flags & BTRFS_BLOCK_GROUP_RAID0)
2146 /* turn mirroring into duplication */
2147 if (flags & (BTRFS_BLOCK_GROUP_RAID1_MASK |
2148 BTRFS_BLOCK_GROUP_RAID10))
2149 return stripped | BTRFS_BLOCK_GROUP_DUP;
2151 /* they already had raid on here, just return */
2152 if (flags & stripped)
2155 stripped |= BTRFS_BLOCK_GROUP_DUP;
2156 stripped = flags & ~stripped;
2158 /* switch duplicated blocks with raid1 */
2159 if (flags & BTRFS_BLOCK_GROUP_DUP)
2160 return stripped | BTRFS_BLOCK_GROUP_RAID1;
2162 /* this is drive concat, leave it alone */
2169 * Mark one block group RO, can be called several times for the same block
2172 * @cache: the destination block group
2173 * @do_chunk_alloc: whether need to do chunk pre-allocation, this is to
2174 * ensure we still have some free space after marking this
2177 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache,
2178 bool do_chunk_alloc)
2180 struct btrfs_fs_info *fs_info = cache->fs_info;
2181 struct btrfs_trans_handle *trans;
2186 trans = btrfs_join_transaction(fs_info->extent_root);
2188 return PTR_ERR(trans);
2191 * we're not allowed to set block groups readonly after the dirty
2192 * block groups cache has started writing. If it already started,
2193 * back off and let this transaction commit
2195 mutex_lock(&fs_info->ro_block_group_mutex);
2196 if (test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &trans->transaction->flags)) {
2197 u64 transid = trans->transid;
2199 mutex_unlock(&fs_info->ro_block_group_mutex);
2200 btrfs_end_transaction(trans);
2202 ret = btrfs_wait_for_commit(fs_info, transid);
2208 if (do_chunk_alloc) {
2210 * If we are changing raid levels, try to allocate a
2211 * corresponding block group with the new raid level.
2213 alloc_flags = update_block_group_flags(fs_info, cache->flags);
2214 if (alloc_flags != cache->flags) {
2215 ret = btrfs_chunk_alloc(trans, alloc_flags,
2218 * ENOSPC is allowed here, we may have enough space
2219 * already allocated at the new raid level to carry on
2228 ret = inc_block_group_ro(cache, !do_chunk_alloc);
2229 if (!do_chunk_alloc)
2233 alloc_flags = btrfs_get_alloc_profile(fs_info, cache->space_info->flags);
2234 ret = btrfs_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
2237 ret = inc_block_group_ro(cache, 0);
2239 if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
2240 alloc_flags = update_block_group_flags(fs_info, cache->flags);
2241 mutex_lock(&fs_info->chunk_mutex);
2242 check_system_chunk(trans, alloc_flags);
2243 mutex_unlock(&fs_info->chunk_mutex);
2246 mutex_unlock(&fs_info->ro_block_group_mutex);
2248 btrfs_end_transaction(trans);
2252 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache)
2254 struct btrfs_space_info *sinfo = cache->space_info;
2259 spin_lock(&sinfo->lock);
2260 spin_lock(&cache->lock);
2262 num_bytes = cache->length - cache->reserved -
2263 cache->pinned - cache->bytes_super - cache->used;
2264 sinfo->bytes_readonly -= num_bytes;
2265 list_del_init(&cache->ro_list);
2267 spin_unlock(&cache->lock);
2268 spin_unlock(&sinfo->lock);
2271 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2272 struct btrfs_path *path,
2273 struct btrfs_block_group *cache)
2275 struct btrfs_fs_info *fs_info = trans->fs_info;
2277 struct btrfs_root *extent_root = fs_info->extent_root;
2279 struct extent_buffer *leaf;
2280 struct btrfs_block_group_item bgi;
2281 struct btrfs_key key;
2283 key.objectid = cache->start;
2284 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
2285 key.offset = cache->length;
2287 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 1);
2294 leaf = path->nodes[0];
2295 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2296 btrfs_set_stack_block_group_used(&bgi, cache->used);
2297 btrfs_set_stack_block_group_chunk_objectid(&bgi,
2298 BTRFS_FIRST_CHUNK_TREE_OBJECTID);
2299 btrfs_set_stack_block_group_flags(&bgi, cache->flags);
2300 write_extent_buffer(leaf, &bgi, bi, sizeof(bgi));
2301 btrfs_mark_buffer_dirty(leaf);
2303 btrfs_release_path(path);
2308 static int cache_save_setup(struct btrfs_block_group *block_group,
2309 struct btrfs_trans_handle *trans,
2310 struct btrfs_path *path)
2312 struct btrfs_fs_info *fs_info = block_group->fs_info;
2313 struct btrfs_root *root = fs_info->tree_root;
2314 struct inode *inode = NULL;
2315 struct extent_changeset *data_reserved = NULL;
2317 int dcs = BTRFS_DC_ERROR;
2323 * If this block group is smaller than 100 megs don't bother caching the
2326 if (block_group->length < (100 * SZ_1M)) {
2327 spin_lock(&block_group->lock);
2328 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2329 spin_unlock(&block_group->lock);
2336 inode = lookup_free_space_inode(block_group, path);
2337 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2338 ret = PTR_ERR(inode);
2339 btrfs_release_path(path);
2343 if (IS_ERR(inode)) {
2347 if (block_group->ro)
2350 ret = create_free_space_inode(trans, block_group, path);
2357 * We want to set the generation to 0, that way if anything goes wrong
2358 * from here on out we know not to trust this cache when we load up next
2361 BTRFS_I(inode)->generation = 0;
2362 ret = btrfs_update_inode(trans, root, inode);
2365 * So theoretically we could recover from this, simply set the
2366 * super cache generation to 0 so we know to invalidate the
2367 * cache, but then we'd have to keep track of the block groups
2368 * that fail this way so we know we _have_ to reset this cache
2369 * before the next commit or risk reading stale cache. So to
2370 * limit our exposure to horrible edge cases lets just abort the
2371 * transaction, this only happens in really bad situations
2374 btrfs_abort_transaction(trans, ret);
2379 /* We've already setup this transaction, go ahead and exit */
2380 if (block_group->cache_generation == trans->transid &&
2381 i_size_read(inode)) {
2382 dcs = BTRFS_DC_SETUP;
2386 if (i_size_read(inode) > 0) {
2387 ret = btrfs_check_trunc_cache_free_space(fs_info,
2388 &fs_info->global_block_rsv);
2392 ret = btrfs_truncate_free_space_cache(trans, NULL, inode);
2397 spin_lock(&block_group->lock);
2398 if (block_group->cached != BTRFS_CACHE_FINISHED ||
2399 !btrfs_test_opt(fs_info, SPACE_CACHE)) {
2401 * don't bother trying to write stuff out _if_
2402 * a) we're not cached,
2403 * b) we're with nospace_cache mount option,
2404 * c) we're with v2 space_cache (FREE_SPACE_TREE).
2406 dcs = BTRFS_DC_WRITTEN;
2407 spin_unlock(&block_group->lock);
2410 spin_unlock(&block_group->lock);
2413 * We hit an ENOSPC when setting up the cache in this transaction, just
2414 * skip doing the setup, we've already cleared the cache so we're safe.
2416 if (test_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags)) {
2422 * Try to preallocate enough space based on how big the block group is.
2423 * Keep in mind this has to include any pinned space which could end up
2424 * taking up quite a bit since it's not folded into the other space
2427 num_pages = div_u64(block_group->length, SZ_256M);
2432 num_pages *= PAGE_SIZE;
2434 ret = btrfs_check_data_free_space(inode, &data_reserved, 0, num_pages);
2438 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2439 num_pages, num_pages,
2442 * Our cache requires contiguous chunks so that we don't modify a bunch
2443 * of metadata or split extents when writing the cache out, which means
2444 * we can enospc if we are heavily fragmented in addition to just normal
2445 * out of space conditions. So if we hit this just skip setting up any
2446 * other block groups for this transaction, maybe we'll unpin enough
2447 * space the next time around.
2450 dcs = BTRFS_DC_SETUP;
2451 else if (ret == -ENOSPC)
2452 set_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags);
2457 btrfs_release_path(path);
2459 spin_lock(&block_group->lock);
2460 if (!ret && dcs == BTRFS_DC_SETUP)
2461 block_group->cache_generation = trans->transid;
2462 block_group->disk_cache_state = dcs;
2463 spin_unlock(&block_group->lock);
2465 extent_changeset_free(data_reserved);
2469 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans)
2471 struct btrfs_fs_info *fs_info = trans->fs_info;
2472 struct btrfs_block_group *cache, *tmp;
2473 struct btrfs_transaction *cur_trans = trans->transaction;
2474 struct btrfs_path *path;
2476 if (list_empty(&cur_trans->dirty_bgs) ||
2477 !btrfs_test_opt(fs_info, SPACE_CACHE))
2480 path = btrfs_alloc_path();
2484 /* Could add new block groups, use _safe just in case */
2485 list_for_each_entry_safe(cache, tmp, &cur_trans->dirty_bgs,
2487 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2488 cache_save_setup(cache, trans, path);
2491 btrfs_free_path(path);
2496 * Transaction commit does final block group cache writeback during a critical
2497 * section where nothing is allowed to change the FS. This is required in
2498 * order for the cache to actually match the block group, but can introduce a
2499 * lot of latency into the commit.
2501 * So, btrfs_start_dirty_block_groups is here to kick off block group cache IO.
2502 * There's a chance we'll have to redo some of it if the block group changes
2503 * again during the commit, but it greatly reduces the commit latency by
2504 * getting rid of the easy block groups while we're still allowing others to
2507 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans)
2509 struct btrfs_fs_info *fs_info = trans->fs_info;
2510 struct btrfs_block_group *cache;
2511 struct btrfs_transaction *cur_trans = trans->transaction;
2514 struct btrfs_path *path = NULL;
2516 struct list_head *io = &cur_trans->io_bgs;
2517 int num_started = 0;
2520 spin_lock(&cur_trans->dirty_bgs_lock);
2521 if (list_empty(&cur_trans->dirty_bgs)) {
2522 spin_unlock(&cur_trans->dirty_bgs_lock);
2525 list_splice_init(&cur_trans->dirty_bgs, &dirty);
2526 spin_unlock(&cur_trans->dirty_bgs_lock);
2529 /* Make sure all the block groups on our dirty list actually exist */
2530 btrfs_create_pending_block_groups(trans);
2533 path = btrfs_alloc_path();
2539 * cache_write_mutex is here only to save us from balance or automatic
2540 * removal of empty block groups deleting this block group while we are
2541 * writing out the cache
2543 mutex_lock(&trans->transaction->cache_write_mutex);
2544 while (!list_empty(&dirty)) {
2545 bool drop_reserve = true;
2547 cache = list_first_entry(&dirty, struct btrfs_block_group,
2550 * This can happen if something re-dirties a block group that
2551 * is already under IO. Just wait for it to finish and then do
2554 if (!list_empty(&cache->io_list)) {
2555 list_del_init(&cache->io_list);
2556 btrfs_wait_cache_io(trans, cache, path);
2557 btrfs_put_block_group(cache);
2562 * btrfs_wait_cache_io uses the cache->dirty_list to decide if
2563 * it should update the cache_state. Don't delete until after
2566 * Since we're not running in the commit critical section
2567 * we need the dirty_bgs_lock to protect from update_block_group
2569 spin_lock(&cur_trans->dirty_bgs_lock);
2570 list_del_init(&cache->dirty_list);
2571 spin_unlock(&cur_trans->dirty_bgs_lock);
2575 cache_save_setup(cache, trans, path);
2577 if (cache->disk_cache_state == BTRFS_DC_SETUP) {
2578 cache->io_ctl.inode = NULL;
2579 ret = btrfs_write_out_cache(trans, cache, path);
2580 if (ret == 0 && cache->io_ctl.inode) {
2585 * The cache_write_mutex is protecting the
2586 * io_list, also refer to the definition of
2587 * btrfs_transaction::io_bgs for more details
2589 list_add_tail(&cache->io_list, io);
2592 * If we failed to write the cache, the
2593 * generation will be bad and life goes on
2599 ret = write_one_cache_group(trans, path, cache);
2601 * Our block group might still be attached to the list
2602 * of new block groups in the transaction handle of some
2603 * other task (struct btrfs_trans_handle->new_bgs). This
2604 * means its block group item isn't yet in the extent
2605 * tree. If this happens ignore the error, as we will
2606 * try again later in the critical section of the
2607 * transaction commit.
2609 if (ret == -ENOENT) {
2611 spin_lock(&cur_trans->dirty_bgs_lock);
2612 if (list_empty(&cache->dirty_list)) {
2613 list_add_tail(&cache->dirty_list,
2614 &cur_trans->dirty_bgs);
2615 btrfs_get_block_group(cache);
2616 drop_reserve = false;
2618 spin_unlock(&cur_trans->dirty_bgs_lock);
2620 btrfs_abort_transaction(trans, ret);
2624 /* If it's not on the io list, we need to put the block group */
2626 btrfs_put_block_group(cache);
2628 btrfs_delayed_refs_rsv_release(fs_info, 1);
2634 * Avoid blocking other tasks for too long. It might even save
2635 * us from writing caches for block groups that are going to be
2638 mutex_unlock(&trans->transaction->cache_write_mutex);
2639 mutex_lock(&trans->transaction->cache_write_mutex);
2641 mutex_unlock(&trans->transaction->cache_write_mutex);
2644 * Go through delayed refs for all the stuff we've just kicked off
2645 * and then loop back (just once)
2647 ret = btrfs_run_delayed_refs(trans, 0);
2648 if (!ret && loops == 0) {
2650 spin_lock(&cur_trans->dirty_bgs_lock);
2651 list_splice_init(&cur_trans->dirty_bgs, &dirty);
2653 * dirty_bgs_lock protects us from concurrent block group
2654 * deletes too (not just cache_write_mutex).
2656 if (!list_empty(&dirty)) {
2657 spin_unlock(&cur_trans->dirty_bgs_lock);
2660 spin_unlock(&cur_trans->dirty_bgs_lock);
2661 } else if (ret < 0) {
2662 btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
2665 btrfs_free_path(path);
2669 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans)
2671 struct btrfs_fs_info *fs_info = trans->fs_info;
2672 struct btrfs_block_group *cache;
2673 struct btrfs_transaction *cur_trans = trans->transaction;
2676 struct btrfs_path *path;
2677 struct list_head *io = &cur_trans->io_bgs;
2678 int num_started = 0;
2680 path = btrfs_alloc_path();
2685 * Even though we are in the critical section of the transaction commit,
2686 * we can still have concurrent tasks adding elements to this
2687 * transaction's list of dirty block groups. These tasks correspond to
2688 * endio free space workers started when writeback finishes for a
2689 * space cache, which run inode.c:btrfs_finish_ordered_io(), and can
2690 * allocate new block groups as a result of COWing nodes of the root
2691 * tree when updating the free space inode. The writeback for the space
2692 * caches is triggered by an earlier call to
2693 * btrfs_start_dirty_block_groups() and iterations of the following
2695 * Also we want to do the cache_save_setup first and then run the
2696 * delayed refs to make sure we have the best chance at doing this all
2699 spin_lock(&cur_trans->dirty_bgs_lock);
2700 while (!list_empty(&cur_trans->dirty_bgs)) {
2701 cache = list_first_entry(&cur_trans->dirty_bgs,
2702 struct btrfs_block_group,
2706 * This can happen if cache_save_setup re-dirties a block group
2707 * that is already under IO. Just wait for it to finish and
2708 * then do it all again
2710 if (!list_empty(&cache->io_list)) {
2711 spin_unlock(&cur_trans->dirty_bgs_lock);
2712 list_del_init(&cache->io_list);
2713 btrfs_wait_cache_io(trans, cache, path);
2714 btrfs_put_block_group(cache);
2715 spin_lock(&cur_trans->dirty_bgs_lock);
2719 * Don't remove from the dirty list until after we've waited on
2722 list_del_init(&cache->dirty_list);
2723 spin_unlock(&cur_trans->dirty_bgs_lock);
2726 cache_save_setup(cache, trans, path);
2729 ret = btrfs_run_delayed_refs(trans,
2730 (unsigned long) -1);
2732 if (!ret && cache->disk_cache_state == BTRFS_DC_SETUP) {
2733 cache->io_ctl.inode = NULL;
2734 ret = btrfs_write_out_cache(trans, cache, path);
2735 if (ret == 0 && cache->io_ctl.inode) {
2738 list_add_tail(&cache->io_list, io);
2741 * If we failed to write the cache, the
2742 * generation will be bad and life goes on
2748 ret = write_one_cache_group(trans, path, cache);
2750 * One of the free space endio workers might have
2751 * created a new block group while updating a free space
2752 * cache's inode (at inode.c:btrfs_finish_ordered_io())
2753 * and hasn't released its transaction handle yet, in
2754 * which case the new block group is still attached to
2755 * its transaction handle and its creation has not
2756 * finished yet (no block group item in the extent tree
2757 * yet, etc). If this is the case, wait for all free
2758 * space endio workers to finish and retry. This is a
2759 * a very rare case so no need for a more efficient and
2762 if (ret == -ENOENT) {
2763 wait_event(cur_trans->writer_wait,
2764 atomic_read(&cur_trans->num_writers) == 1);
2765 ret = write_one_cache_group(trans, path, cache);
2768 btrfs_abort_transaction(trans, ret);
2771 /* If its not on the io list, we need to put the block group */
2773 btrfs_put_block_group(cache);
2774 btrfs_delayed_refs_rsv_release(fs_info, 1);
2775 spin_lock(&cur_trans->dirty_bgs_lock);
2777 spin_unlock(&cur_trans->dirty_bgs_lock);
2780 * Refer to the definition of io_bgs member for details why it's safe
2781 * to use it without any locking
2783 while (!list_empty(io)) {
2784 cache = list_first_entry(io, struct btrfs_block_group,
2786 list_del_init(&cache->io_list);
2787 btrfs_wait_cache_io(trans, cache, path);
2788 btrfs_put_block_group(cache);
2791 btrfs_free_path(path);
2795 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
2796 u64 bytenr, u64 num_bytes, int alloc)
2798 struct btrfs_fs_info *info = trans->fs_info;
2799 struct btrfs_block_group *cache = NULL;
2800 u64 total = num_bytes;
2806 /* Block accounting for super block */
2807 spin_lock(&info->delalloc_root_lock);
2808 old_val = btrfs_super_bytes_used(info->super_copy);
2810 old_val += num_bytes;
2812 old_val -= num_bytes;
2813 btrfs_set_super_bytes_used(info->super_copy, old_val);
2814 spin_unlock(&info->delalloc_root_lock);
2817 cache = btrfs_lookup_block_group(info, bytenr);
2822 factor = btrfs_bg_type_to_factor(cache->flags);
2825 * If this block group has free space cache written out, we
2826 * need to make sure to load it if we are removing space. This
2827 * is because we need the unpinning stage to actually add the
2828 * space back to the block group, otherwise we will leak space.
2830 if (!alloc && !btrfs_block_group_done(cache))
2831 btrfs_cache_block_group(cache, 1);
2833 byte_in_group = bytenr - cache->start;
2834 WARN_ON(byte_in_group > cache->length);
2836 spin_lock(&cache->space_info->lock);
2837 spin_lock(&cache->lock);
2839 if (btrfs_test_opt(info, SPACE_CACHE) &&
2840 cache->disk_cache_state < BTRFS_DC_CLEAR)
2841 cache->disk_cache_state = BTRFS_DC_CLEAR;
2843 old_val = cache->used;
2844 num_bytes = min(total, cache->length - byte_in_group);
2846 old_val += num_bytes;
2847 cache->used = old_val;
2848 cache->reserved -= num_bytes;
2849 cache->space_info->bytes_reserved -= num_bytes;
2850 cache->space_info->bytes_used += num_bytes;
2851 cache->space_info->disk_used += num_bytes * factor;
2852 spin_unlock(&cache->lock);
2853 spin_unlock(&cache->space_info->lock);
2855 old_val -= num_bytes;
2856 cache->used = old_val;
2857 cache->pinned += num_bytes;
2858 btrfs_space_info_update_bytes_pinned(info,
2859 cache->space_info, num_bytes);
2860 cache->space_info->bytes_used -= num_bytes;
2861 cache->space_info->disk_used -= num_bytes * factor;
2862 spin_unlock(&cache->lock);
2863 spin_unlock(&cache->space_info->lock);
2865 percpu_counter_add_batch(
2866 &cache->space_info->total_bytes_pinned,
2868 BTRFS_TOTAL_BYTES_PINNED_BATCH);
2869 set_extent_dirty(info->pinned_extents,
2870 bytenr, bytenr + num_bytes - 1,
2871 GFP_NOFS | __GFP_NOFAIL);
2874 spin_lock(&trans->transaction->dirty_bgs_lock);
2875 if (list_empty(&cache->dirty_list)) {
2876 list_add_tail(&cache->dirty_list,
2877 &trans->transaction->dirty_bgs);
2878 trans->delayed_ref_updates++;
2879 btrfs_get_block_group(cache);
2881 spin_unlock(&trans->transaction->dirty_bgs_lock);
2884 * No longer have used bytes in this block group, queue it for
2885 * deletion. We do this after adding the block group to the
2886 * dirty list to avoid races between cleaner kthread and space
2889 if (!alloc && old_val == 0) {
2890 if (!btrfs_test_opt(info, DISCARD_ASYNC))
2891 btrfs_mark_bg_unused(cache);
2894 btrfs_put_block_group(cache);
2896 bytenr += num_bytes;
2899 /* Modified block groups are accounted for in the delayed_refs_rsv. */
2900 btrfs_update_delayed_refs_rsv(trans);
2905 * btrfs_add_reserved_bytes - update the block_group and space info counters
2906 * @cache: The cache we are manipulating
2907 * @ram_bytes: The number of bytes of file content, and will be same to
2908 * @num_bytes except for the compress path.
2909 * @num_bytes: The number of bytes in question
2910 * @delalloc: The blocks are allocated for the delalloc write
2912 * This is called by the allocator when it reserves space. If this is a
2913 * reservation and the block group has become read only we cannot make the
2914 * reservation and return -EAGAIN, otherwise this function always succeeds.
2916 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache,
2917 u64 ram_bytes, u64 num_bytes, int delalloc)
2919 struct btrfs_space_info *space_info = cache->space_info;
2922 spin_lock(&space_info->lock);
2923 spin_lock(&cache->lock);
2927 cache->reserved += num_bytes;
2928 space_info->bytes_reserved += num_bytes;
2929 trace_btrfs_space_reservation(cache->fs_info, "space_info",
2930 space_info->flags, num_bytes, 1);
2931 btrfs_space_info_update_bytes_may_use(cache->fs_info,
2932 space_info, -ram_bytes);
2934 cache->delalloc_bytes += num_bytes;
2936 spin_unlock(&cache->lock);
2937 spin_unlock(&space_info->lock);
2942 * btrfs_free_reserved_bytes - update the block_group and space info counters
2943 * @cache: The cache we are manipulating
2944 * @num_bytes: The number of bytes in question
2945 * @delalloc: The blocks are allocated for the delalloc write
2947 * This is called by somebody who is freeing space that was never actually used
2948 * on disk. For example if you reserve some space for a new leaf in transaction
2949 * A and before transaction A commits you free that leaf, you call this with
2950 * reserve set to 0 in order to clear the reservation.
2952 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache,
2953 u64 num_bytes, int delalloc)
2955 struct btrfs_space_info *space_info = cache->space_info;
2957 spin_lock(&space_info->lock);
2958 spin_lock(&cache->lock);
2960 space_info->bytes_readonly += num_bytes;
2961 cache->reserved -= num_bytes;
2962 space_info->bytes_reserved -= num_bytes;
2963 space_info->max_extent_size = 0;
2966 cache->delalloc_bytes -= num_bytes;
2967 spin_unlock(&cache->lock);
2968 spin_unlock(&space_info->lock);
2971 static void force_metadata_allocation(struct btrfs_fs_info *info)
2973 struct list_head *head = &info->space_info;
2974 struct btrfs_space_info *found;
2977 list_for_each_entry_rcu(found, head, list) {
2978 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
2979 found->force_alloc = CHUNK_ALLOC_FORCE;
2984 static int should_alloc_chunk(struct btrfs_fs_info *fs_info,
2985 struct btrfs_space_info *sinfo, int force)
2987 u64 bytes_used = btrfs_space_info_used(sinfo, false);
2990 if (force == CHUNK_ALLOC_FORCE)
2994 * in limited mode, we want to have some free space up to
2995 * about 1% of the FS size.
2997 if (force == CHUNK_ALLOC_LIMITED) {
2998 thresh = btrfs_super_total_bytes(fs_info->super_copy);
2999 thresh = max_t(u64, SZ_64M, div_factor_fine(thresh, 1));
3001 if (sinfo->total_bytes - bytes_used < thresh)
3005 if (bytes_used + SZ_2M < div_factor(sinfo->total_bytes, 8))
3010 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type)
3012 u64 alloc_flags = btrfs_get_alloc_profile(trans->fs_info, type);
3014 return btrfs_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
3018 * If force is CHUNK_ALLOC_FORCE:
3019 * - return 1 if it successfully allocates a chunk,
3020 * - return errors including -ENOSPC otherwise.
3021 * If force is NOT CHUNK_ALLOC_FORCE:
3022 * - return 0 if it doesn't need to allocate a new chunk,
3023 * - return 1 if it successfully allocates a chunk,
3024 * - return errors including -ENOSPC otherwise.
3026 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
3027 enum btrfs_chunk_alloc_enum force)
3029 struct btrfs_fs_info *fs_info = trans->fs_info;
3030 struct btrfs_space_info *space_info;
3031 bool wait_for_alloc = false;
3032 bool should_alloc = false;
3035 /* Don't re-enter if we're already allocating a chunk */
3036 if (trans->allocating_chunk)
3039 space_info = btrfs_find_space_info(fs_info, flags);
3043 spin_lock(&space_info->lock);
3044 if (force < space_info->force_alloc)
3045 force = space_info->force_alloc;
3046 should_alloc = should_alloc_chunk(fs_info, space_info, force);
3047 if (space_info->full) {
3048 /* No more free physical space */
3053 spin_unlock(&space_info->lock);
3055 } else if (!should_alloc) {
3056 spin_unlock(&space_info->lock);
3058 } else if (space_info->chunk_alloc) {
3060 * Someone is already allocating, so we need to block
3061 * until this someone is finished and then loop to
3062 * recheck if we should continue with our allocation
3065 wait_for_alloc = true;
3066 spin_unlock(&space_info->lock);
3067 mutex_lock(&fs_info->chunk_mutex);
3068 mutex_unlock(&fs_info->chunk_mutex);
3070 /* Proceed with allocation */
3071 space_info->chunk_alloc = 1;
3072 wait_for_alloc = false;
3073 spin_unlock(&space_info->lock);
3077 } while (wait_for_alloc);
3079 mutex_lock(&fs_info->chunk_mutex);
3080 trans->allocating_chunk = true;
3083 * If we have mixed data/metadata chunks we want to make sure we keep
3084 * allocating mixed chunks instead of individual chunks.
3086 if (btrfs_mixed_space_info(space_info))
3087 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3090 * if we're doing a data chunk, go ahead and make sure that
3091 * we keep a reasonable number of metadata chunks allocated in the
3094 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3095 fs_info->data_chunk_allocations++;
3096 if (!(fs_info->data_chunk_allocations %
3097 fs_info->metadata_ratio))
3098 force_metadata_allocation(fs_info);
3102 * Check if we have enough space in SYSTEM chunk because we may need
3103 * to update devices.
3105 check_system_chunk(trans, flags);
3107 ret = btrfs_alloc_chunk(trans, flags);
3108 trans->allocating_chunk = false;
3110 spin_lock(&space_info->lock);
3113 space_info->full = 1;
3118 space_info->max_extent_size = 0;
3121 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3123 space_info->chunk_alloc = 0;
3124 spin_unlock(&space_info->lock);
3125 mutex_unlock(&fs_info->chunk_mutex);
3127 * When we allocate a new chunk we reserve space in the chunk block
3128 * reserve to make sure we can COW nodes/leafs in the chunk tree or
3129 * add new nodes/leafs to it if we end up needing to do it when
3130 * inserting the chunk item and updating device items as part of the
3131 * second phase of chunk allocation, performed by
3132 * btrfs_finish_chunk_alloc(). So make sure we don't accumulate a
3133 * large number of new block groups to create in our transaction
3134 * handle's new_bgs list to avoid exhausting the chunk block reserve
3135 * in extreme cases - like having a single transaction create many new
3136 * block groups when starting to write out the free space caches of all
3137 * the block groups that were made dirty during the lifetime of the
3140 if (trans->chunk_bytes_reserved >= (u64)SZ_2M)
3141 btrfs_create_pending_block_groups(trans);
3146 static u64 get_profile_num_devs(struct btrfs_fs_info *fs_info, u64 type)
3150 num_dev = btrfs_raid_array[btrfs_bg_flags_to_raid_index(type)].devs_max;
3152 num_dev = fs_info->fs_devices->rw_devices;
3158 * Reserve space in the system space for allocating or removing a chunk
3160 void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
3162 struct btrfs_fs_info *fs_info = trans->fs_info;
3163 struct btrfs_space_info *info;
3170 * Needed because we can end up allocating a system chunk and for an
3171 * atomic and race free space reservation in the chunk block reserve.
3173 lockdep_assert_held(&fs_info->chunk_mutex);
3175 info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3176 spin_lock(&info->lock);
3177 left = info->total_bytes - btrfs_space_info_used(info, true);
3178 spin_unlock(&info->lock);
3180 num_devs = get_profile_num_devs(fs_info, type);
3182 /* num_devs device items to update and 1 chunk item to add or remove */
3183 thresh = btrfs_calc_metadata_size(fs_info, num_devs) +
3184 btrfs_calc_insert_metadata_size(fs_info, 1);
3186 if (left < thresh && btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
3187 btrfs_info(fs_info, "left=%llu, need=%llu, flags=%llu",
3188 left, thresh, type);
3189 btrfs_dump_space_info(fs_info, info, 0, 0);
3192 if (left < thresh) {
3193 u64 flags = btrfs_system_alloc_profile(fs_info);
3196 * Ignore failure to create system chunk. We might end up not
3197 * needing it, as we might not need to COW all nodes/leafs from
3198 * the paths we visit in the chunk tree (they were already COWed
3199 * or created in the current transaction for example).
3201 ret = btrfs_alloc_chunk(trans, flags);
3205 ret = btrfs_block_rsv_add(fs_info->chunk_root,
3206 &fs_info->chunk_block_rsv,
3207 thresh, BTRFS_RESERVE_NO_FLUSH);
3209 trans->chunk_bytes_reserved += thresh;
3213 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
3215 struct btrfs_block_group *block_group;
3219 struct inode *inode;
3221 block_group = btrfs_lookup_first_block_group(info, last);
3222 while (block_group) {
3223 btrfs_wait_block_group_cache_done(block_group);
3224 spin_lock(&block_group->lock);
3225 if (block_group->iref)
3227 spin_unlock(&block_group->lock);
3228 block_group = btrfs_next_block_group(block_group);
3237 inode = block_group->inode;
3238 block_group->iref = 0;
3239 block_group->inode = NULL;
3240 spin_unlock(&block_group->lock);
3241 ASSERT(block_group->io_ctl.inode == NULL);
3243 last = block_group->start + block_group->length;
3244 btrfs_put_block_group(block_group);
3249 * Must be called only after stopping all workers, since we could have block
3250 * group caching kthreads running, and therefore they could race with us if we
3251 * freed the block groups before stopping them.
3253 int btrfs_free_block_groups(struct btrfs_fs_info *info)
3255 struct btrfs_block_group *block_group;
3256 struct btrfs_space_info *space_info;
3257 struct btrfs_caching_control *caching_ctl;
3260 down_write(&info->commit_root_sem);
3261 while (!list_empty(&info->caching_block_groups)) {
3262 caching_ctl = list_entry(info->caching_block_groups.next,
3263 struct btrfs_caching_control, list);
3264 list_del(&caching_ctl->list);
3265 btrfs_put_caching_control(caching_ctl);
3267 up_write(&info->commit_root_sem);
3269 spin_lock(&info->unused_bgs_lock);
3270 while (!list_empty(&info->unused_bgs)) {
3271 block_group = list_first_entry(&info->unused_bgs,
3272 struct btrfs_block_group,
3274 list_del_init(&block_group->bg_list);
3275 btrfs_put_block_group(block_group);
3277 spin_unlock(&info->unused_bgs_lock);
3279 spin_lock(&info->block_group_cache_lock);
3280 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
3281 block_group = rb_entry(n, struct btrfs_block_group,
3283 rb_erase(&block_group->cache_node,
3284 &info->block_group_cache_tree);
3285 RB_CLEAR_NODE(&block_group->cache_node);
3286 spin_unlock(&info->block_group_cache_lock);
3288 down_write(&block_group->space_info->groups_sem);
3289 list_del(&block_group->list);
3290 up_write(&block_group->space_info->groups_sem);
3293 * We haven't cached this block group, which means we could
3294 * possibly have excluded extents on this block group.
3296 if (block_group->cached == BTRFS_CACHE_NO ||
3297 block_group->cached == BTRFS_CACHE_ERROR)
3298 btrfs_free_excluded_extents(block_group);
3300 btrfs_remove_free_space_cache(block_group);
3301 ASSERT(block_group->cached != BTRFS_CACHE_STARTED);
3302 ASSERT(list_empty(&block_group->dirty_list));
3303 ASSERT(list_empty(&block_group->io_list));
3304 ASSERT(list_empty(&block_group->bg_list));
3305 ASSERT(atomic_read(&block_group->count) == 1);
3306 btrfs_put_block_group(block_group);
3308 spin_lock(&info->block_group_cache_lock);
3310 spin_unlock(&info->block_group_cache_lock);
3313 * Now that all the block groups are freed, go through and free all the
3314 * space_info structs. This is only called during the final stages of
3315 * unmount, and so we know nobody is using them. We call
3316 * synchronize_rcu() once before we start, just to be on the safe side.
3320 btrfs_release_global_block_rsv(info);
3322 while (!list_empty(&info->space_info)) {
3323 space_info = list_entry(info->space_info.next,
3324 struct btrfs_space_info,
3328 * Do not hide this behind enospc_debug, this is actually
3329 * important and indicates a real bug if this happens.
3331 if (WARN_ON(space_info->bytes_pinned > 0 ||
3332 space_info->bytes_reserved > 0 ||
3333 space_info->bytes_may_use > 0))
3334 btrfs_dump_space_info(info, space_info, 0, 0);
3335 list_del(&space_info->list);
3336 btrfs_sysfs_remove_space_info(space_info);