1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
6 #include <linux/sched.h>
7 #include <linux/sched/signal.h>
8 #include <linux/pagemap.h>
9 #include <linux/writeback.h>
10 #include <linux/blkdev.h>
11 #include <linux/sort.h>
12 #include <linux/rcupdate.h>
13 #include <linux/kthread.h>
14 #include <linux/slab.h>
15 #include <linux/ratelimit.h>
16 #include <linux/percpu_counter.h>
17 #include <linux/lockdep.h>
18 #include <linux/crc32c.h>
21 #include "print-tree.h"
25 #include "free-space-cache.h"
26 #include "free-space-tree.h"
30 #include "ref-verify.h"
32 #undef SCRAMBLE_DELAYED_REFS
35 * control flags for do_chunk_alloc's force field
36 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
37 * if we really need one.
39 * CHUNK_ALLOC_LIMITED means to only try and allocate one
40 * if we have very few chunks already allocated. This is
41 * used as part of the clustering code to help make sure
42 * we have a good pool of storage to cluster in, without
43 * filling the FS with empty chunks
45 * CHUNK_ALLOC_FORCE means it must try to allocate one
49 CHUNK_ALLOC_NO_FORCE
= 0,
50 CHUNK_ALLOC_LIMITED
= 1,
51 CHUNK_ALLOC_FORCE
= 2,
54 static int __btrfs_free_extent(struct btrfs_trans_handle
*trans
,
55 struct btrfs_delayed_ref_node
*node
, u64 parent
,
56 u64 root_objectid
, u64 owner_objectid
,
57 u64 owner_offset
, int refs_to_drop
,
58 struct btrfs_delayed_extent_op
*extra_op
);
59 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op
*extent_op
,
60 struct extent_buffer
*leaf
,
61 struct btrfs_extent_item
*ei
);
62 static int alloc_reserved_file_extent(struct btrfs_trans_handle
*trans
,
63 u64 parent
, u64 root_objectid
,
64 u64 flags
, u64 owner
, u64 offset
,
65 struct btrfs_key
*ins
, int ref_mod
);
66 static int alloc_reserved_tree_block(struct btrfs_trans_handle
*trans
,
67 struct btrfs_delayed_ref_node
*node
,
68 struct btrfs_delayed_extent_op
*extent_op
);
69 static int do_chunk_alloc(struct btrfs_trans_handle
*trans
, u64 flags
,
71 static int find_next_key(struct btrfs_path
*path
, int level
,
72 struct btrfs_key
*key
);
73 static void dump_space_info(struct btrfs_fs_info
*fs_info
,
74 struct btrfs_space_info
*info
, u64 bytes
,
75 int dump_block_groups
);
76 static int block_rsv_use_bytes(struct btrfs_block_rsv
*block_rsv
,
78 static void space_info_add_new_bytes(struct btrfs_fs_info
*fs_info
,
79 struct btrfs_space_info
*space_info
,
81 static void space_info_add_old_bytes(struct btrfs_fs_info
*fs_info
,
82 struct btrfs_space_info
*space_info
,
86 block_group_cache_done(struct btrfs_block_group_cache
*cache
)
89 return cache
->cached
== BTRFS_CACHE_FINISHED
||
90 cache
->cached
== BTRFS_CACHE_ERROR
;
93 static int block_group_bits(struct btrfs_block_group_cache
*cache
, u64 bits
)
95 return (cache
->flags
& bits
) == bits
;
98 void btrfs_get_block_group(struct btrfs_block_group_cache
*cache
)
100 atomic_inc(&cache
->count
);
103 void btrfs_put_block_group(struct btrfs_block_group_cache
*cache
)
105 if (atomic_dec_and_test(&cache
->count
)) {
106 WARN_ON(cache
->pinned
> 0);
107 WARN_ON(cache
->reserved
> 0);
110 * If not empty, someone is still holding mutex of
111 * full_stripe_lock, which can only be released by caller.
112 * And it will definitely cause use-after-free when caller
113 * tries to release full stripe lock.
115 * No better way to resolve, but only to warn.
117 WARN_ON(!RB_EMPTY_ROOT(&cache
->full_stripe_locks_root
.root
));
118 kfree(cache
->free_space_ctl
);
124 * this adds the block group to the fs_info rb tree for the block group
127 static int btrfs_add_block_group_cache(struct btrfs_fs_info
*info
,
128 struct btrfs_block_group_cache
*block_group
)
131 struct rb_node
*parent
= NULL
;
132 struct btrfs_block_group_cache
*cache
;
134 spin_lock(&info
->block_group_cache_lock
);
135 p
= &info
->block_group_cache_tree
.rb_node
;
139 cache
= rb_entry(parent
, struct btrfs_block_group_cache
,
141 if (block_group
->key
.objectid
< cache
->key
.objectid
) {
143 } else if (block_group
->key
.objectid
> cache
->key
.objectid
) {
146 spin_unlock(&info
->block_group_cache_lock
);
151 rb_link_node(&block_group
->cache_node
, parent
, p
);
152 rb_insert_color(&block_group
->cache_node
,
153 &info
->block_group_cache_tree
);
155 if (info
->first_logical_byte
> block_group
->key
.objectid
)
156 info
->first_logical_byte
= block_group
->key
.objectid
;
158 spin_unlock(&info
->block_group_cache_lock
);
164 * This will return the block group at or after bytenr if contains is 0, else
165 * it will return the block group that contains the bytenr
167 static struct btrfs_block_group_cache
*
168 block_group_cache_tree_search(struct btrfs_fs_info
*info
, u64 bytenr
,
171 struct btrfs_block_group_cache
*cache
, *ret
= NULL
;
175 spin_lock(&info
->block_group_cache_lock
);
176 n
= info
->block_group_cache_tree
.rb_node
;
179 cache
= rb_entry(n
, struct btrfs_block_group_cache
,
181 end
= cache
->key
.objectid
+ cache
->key
.offset
- 1;
182 start
= cache
->key
.objectid
;
184 if (bytenr
< start
) {
185 if (!contains
&& (!ret
|| start
< ret
->key
.objectid
))
188 } else if (bytenr
> start
) {
189 if (contains
&& bytenr
<= end
) {
200 btrfs_get_block_group(ret
);
201 if (bytenr
== 0 && info
->first_logical_byte
> ret
->key
.objectid
)
202 info
->first_logical_byte
= ret
->key
.objectid
;
204 spin_unlock(&info
->block_group_cache_lock
);
209 static int add_excluded_extent(struct btrfs_fs_info
*fs_info
,
210 u64 start
, u64 num_bytes
)
212 u64 end
= start
+ num_bytes
- 1;
213 set_extent_bits(&fs_info
->freed_extents
[0],
214 start
, end
, EXTENT_UPTODATE
);
215 set_extent_bits(&fs_info
->freed_extents
[1],
216 start
, end
, EXTENT_UPTODATE
);
220 static void free_excluded_extents(struct btrfs_block_group_cache
*cache
)
222 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
225 start
= cache
->key
.objectid
;
226 end
= start
+ cache
->key
.offset
- 1;
228 clear_extent_bits(&fs_info
->freed_extents
[0],
229 start
, end
, EXTENT_UPTODATE
);
230 clear_extent_bits(&fs_info
->freed_extents
[1],
231 start
, end
, EXTENT_UPTODATE
);
234 static int exclude_super_stripes(struct btrfs_block_group_cache
*cache
)
236 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
242 if (cache
->key
.objectid
< BTRFS_SUPER_INFO_OFFSET
) {
243 stripe_len
= BTRFS_SUPER_INFO_OFFSET
- cache
->key
.objectid
;
244 cache
->bytes_super
+= stripe_len
;
245 ret
= add_excluded_extent(fs_info
, cache
->key
.objectid
,
251 for (i
= 0; i
< BTRFS_SUPER_MIRROR_MAX
; i
++) {
252 bytenr
= btrfs_sb_offset(i
);
253 ret
= btrfs_rmap_block(fs_info
, cache
->key
.objectid
,
254 bytenr
, &logical
, &nr
, &stripe_len
);
261 if (logical
[nr
] > cache
->key
.objectid
+
265 if (logical
[nr
] + stripe_len
<= cache
->key
.objectid
)
269 if (start
< cache
->key
.objectid
) {
270 start
= cache
->key
.objectid
;
271 len
= (logical
[nr
] + stripe_len
) - start
;
273 len
= min_t(u64
, stripe_len
,
274 cache
->key
.objectid
+
275 cache
->key
.offset
- start
);
278 cache
->bytes_super
+= len
;
279 ret
= add_excluded_extent(fs_info
, start
, len
);
291 static struct btrfs_caching_control
*
292 get_caching_control(struct btrfs_block_group_cache
*cache
)
294 struct btrfs_caching_control
*ctl
;
296 spin_lock(&cache
->lock
);
297 if (!cache
->caching_ctl
) {
298 spin_unlock(&cache
->lock
);
302 ctl
= cache
->caching_ctl
;
303 refcount_inc(&ctl
->count
);
304 spin_unlock(&cache
->lock
);
308 static void put_caching_control(struct btrfs_caching_control
*ctl
)
310 if (refcount_dec_and_test(&ctl
->count
))
314 #ifdef CONFIG_BTRFS_DEBUG
315 static void fragment_free_space(struct btrfs_block_group_cache
*block_group
)
317 struct btrfs_fs_info
*fs_info
= block_group
->fs_info
;
318 u64 start
= block_group
->key
.objectid
;
319 u64 len
= block_group
->key
.offset
;
320 u64 chunk
= block_group
->flags
& BTRFS_BLOCK_GROUP_METADATA
?
321 fs_info
->nodesize
: fs_info
->sectorsize
;
322 u64 step
= chunk
<< 1;
324 while (len
> chunk
) {
325 btrfs_remove_free_space(block_group
, start
, chunk
);
336 * this is only called by cache_block_group, since we could have freed extents
337 * we need to check the pinned_extents for any extents that can't be used yet
338 * since their free space will be released as soon as the transaction commits.
340 u64
add_new_free_space(struct btrfs_block_group_cache
*block_group
,
343 struct btrfs_fs_info
*info
= block_group
->fs_info
;
344 u64 extent_start
, extent_end
, size
, total_added
= 0;
347 while (start
< end
) {
348 ret
= find_first_extent_bit(info
->pinned_extents
, start
,
349 &extent_start
, &extent_end
,
350 EXTENT_DIRTY
| EXTENT_UPTODATE
,
355 if (extent_start
<= start
) {
356 start
= extent_end
+ 1;
357 } else if (extent_start
> start
&& extent_start
< end
) {
358 size
= extent_start
- start
;
360 ret
= btrfs_add_free_space(block_group
, start
,
362 BUG_ON(ret
); /* -ENOMEM or logic error */
363 start
= extent_end
+ 1;
372 ret
= btrfs_add_free_space(block_group
, start
, size
);
373 BUG_ON(ret
); /* -ENOMEM or logic error */
379 static int load_extent_tree_free(struct btrfs_caching_control
*caching_ctl
)
381 struct btrfs_block_group_cache
*block_group
= caching_ctl
->block_group
;
382 struct btrfs_fs_info
*fs_info
= block_group
->fs_info
;
383 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
384 struct btrfs_path
*path
;
385 struct extent_buffer
*leaf
;
386 struct btrfs_key key
;
393 path
= btrfs_alloc_path();
397 last
= max_t(u64
, block_group
->key
.objectid
, BTRFS_SUPER_INFO_OFFSET
);
399 #ifdef CONFIG_BTRFS_DEBUG
401 * If we're fragmenting we don't want to make anybody think we can
402 * allocate from this block group until we've had a chance to fragment
405 if (btrfs_should_fragment_free_space(block_group
))
409 * We don't want to deadlock with somebody trying to allocate a new
410 * extent for the extent root while also trying to search the extent
411 * root to add free space. So we skip locking and search the commit
412 * root, since its read-only
414 path
->skip_locking
= 1;
415 path
->search_commit_root
= 1;
416 path
->reada
= READA_FORWARD
;
420 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
423 ret
= btrfs_search_slot(NULL
, extent_root
, &key
, path
, 0, 0);
427 leaf
= path
->nodes
[0];
428 nritems
= btrfs_header_nritems(leaf
);
431 if (btrfs_fs_closing(fs_info
) > 1) {
436 if (path
->slots
[0] < nritems
) {
437 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
439 ret
= find_next_key(path
, 0, &key
);
443 if (need_resched() ||
444 rwsem_is_contended(&fs_info
->commit_root_sem
)) {
446 caching_ctl
->progress
= last
;
447 btrfs_release_path(path
);
448 up_read(&fs_info
->commit_root_sem
);
449 mutex_unlock(&caching_ctl
->mutex
);
451 mutex_lock(&caching_ctl
->mutex
);
452 down_read(&fs_info
->commit_root_sem
);
456 ret
= btrfs_next_leaf(extent_root
, path
);
461 leaf
= path
->nodes
[0];
462 nritems
= btrfs_header_nritems(leaf
);
466 if (key
.objectid
< last
) {
469 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
472 caching_ctl
->progress
= last
;
473 btrfs_release_path(path
);
477 if (key
.objectid
< block_group
->key
.objectid
) {
482 if (key
.objectid
>= block_group
->key
.objectid
+
483 block_group
->key
.offset
)
486 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
||
487 key
.type
== BTRFS_METADATA_ITEM_KEY
) {
488 total_found
+= add_new_free_space(block_group
, last
,
490 if (key
.type
== BTRFS_METADATA_ITEM_KEY
)
491 last
= key
.objectid
+
494 last
= key
.objectid
+ key
.offset
;
496 if (total_found
> CACHING_CTL_WAKE_UP
) {
499 wake_up(&caching_ctl
->wait
);
506 total_found
+= add_new_free_space(block_group
, last
,
507 block_group
->key
.objectid
+
508 block_group
->key
.offset
);
509 caching_ctl
->progress
= (u64
)-1;
512 btrfs_free_path(path
);
516 static noinline
void caching_thread(struct btrfs_work
*work
)
518 struct btrfs_block_group_cache
*block_group
;
519 struct btrfs_fs_info
*fs_info
;
520 struct btrfs_caching_control
*caching_ctl
;
523 caching_ctl
= container_of(work
, struct btrfs_caching_control
, work
);
524 block_group
= caching_ctl
->block_group
;
525 fs_info
= block_group
->fs_info
;
527 mutex_lock(&caching_ctl
->mutex
);
528 down_read(&fs_info
->commit_root_sem
);
530 if (btrfs_fs_compat_ro(fs_info
, FREE_SPACE_TREE
))
531 ret
= load_free_space_tree(caching_ctl
);
533 ret
= load_extent_tree_free(caching_ctl
);
535 spin_lock(&block_group
->lock
);
536 block_group
->caching_ctl
= NULL
;
537 block_group
->cached
= ret
? BTRFS_CACHE_ERROR
: BTRFS_CACHE_FINISHED
;
538 spin_unlock(&block_group
->lock
);
540 #ifdef CONFIG_BTRFS_DEBUG
541 if (btrfs_should_fragment_free_space(block_group
)) {
544 spin_lock(&block_group
->space_info
->lock
);
545 spin_lock(&block_group
->lock
);
546 bytes_used
= block_group
->key
.offset
-
547 btrfs_block_group_used(&block_group
->item
);
548 block_group
->space_info
->bytes_used
+= bytes_used
>> 1;
549 spin_unlock(&block_group
->lock
);
550 spin_unlock(&block_group
->space_info
->lock
);
551 fragment_free_space(block_group
);
555 caching_ctl
->progress
= (u64
)-1;
557 up_read(&fs_info
->commit_root_sem
);
558 free_excluded_extents(block_group
);
559 mutex_unlock(&caching_ctl
->mutex
);
561 wake_up(&caching_ctl
->wait
);
563 put_caching_control(caching_ctl
);
564 btrfs_put_block_group(block_group
);
567 static int cache_block_group(struct btrfs_block_group_cache
*cache
,
571 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
572 struct btrfs_caching_control
*caching_ctl
;
575 caching_ctl
= kzalloc(sizeof(*caching_ctl
), GFP_NOFS
);
579 INIT_LIST_HEAD(&caching_ctl
->list
);
580 mutex_init(&caching_ctl
->mutex
);
581 init_waitqueue_head(&caching_ctl
->wait
);
582 caching_ctl
->block_group
= cache
;
583 caching_ctl
->progress
= cache
->key
.objectid
;
584 refcount_set(&caching_ctl
->count
, 1);
585 btrfs_init_work(&caching_ctl
->work
, btrfs_cache_helper
,
586 caching_thread
, NULL
, NULL
);
588 spin_lock(&cache
->lock
);
590 * This should be a rare occasion, but this could happen I think in the
591 * case where one thread starts to load the space cache info, and then
592 * some other thread starts a transaction commit which tries to do an
593 * allocation while the other thread is still loading the space cache
594 * info. The previous loop should have kept us from choosing this block
595 * group, but if we've moved to the state where we will wait on caching
596 * block groups we need to first check if we're doing a fast load here,
597 * so we can wait for it to finish, otherwise we could end up allocating
598 * from a block group who's cache gets evicted for one reason or
601 while (cache
->cached
== BTRFS_CACHE_FAST
) {
602 struct btrfs_caching_control
*ctl
;
604 ctl
= cache
->caching_ctl
;
605 refcount_inc(&ctl
->count
);
606 prepare_to_wait(&ctl
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
607 spin_unlock(&cache
->lock
);
611 finish_wait(&ctl
->wait
, &wait
);
612 put_caching_control(ctl
);
613 spin_lock(&cache
->lock
);
616 if (cache
->cached
!= BTRFS_CACHE_NO
) {
617 spin_unlock(&cache
->lock
);
621 WARN_ON(cache
->caching_ctl
);
622 cache
->caching_ctl
= caching_ctl
;
623 cache
->cached
= BTRFS_CACHE_FAST
;
624 spin_unlock(&cache
->lock
);
626 if (btrfs_test_opt(fs_info
, SPACE_CACHE
)) {
627 mutex_lock(&caching_ctl
->mutex
);
628 ret
= load_free_space_cache(fs_info
, cache
);
630 spin_lock(&cache
->lock
);
632 cache
->caching_ctl
= NULL
;
633 cache
->cached
= BTRFS_CACHE_FINISHED
;
634 cache
->last_byte_to_unpin
= (u64
)-1;
635 caching_ctl
->progress
= (u64
)-1;
637 if (load_cache_only
) {
638 cache
->caching_ctl
= NULL
;
639 cache
->cached
= BTRFS_CACHE_NO
;
641 cache
->cached
= BTRFS_CACHE_STARTED
;
642 cache
->has_caching_ctl
= 1;
645 spin_unlock(&cache
->lock
);
646 #ifdef CONFIG_BTRFS_DEBUG
648 btrfs_should_fragment_free_space(cache
)) {
651 spin_lock(&cache
->space_info
->lock
);
652 spin_lock(&cache
->lock
);
653 bytes_used
= cache
->key
.offset
-
654 btrfs_block_group_used(&cache
->item
);
655 cache
->space_info
->bytes_used
+= bytes_used
>> 1;
656 spin_unlock(&cache
->lock
);
657 spin_unlock(&cache
->space_info
->lock
);
658 fragment_free_space(cache
);
661 mutex_unlock(&caching_ctl
->mutex
);
663 wake_up(&caching_ctl
->wait
);
665 put_caching_control(caching_ctl
);
666 free_excluded_extents(cache
);
671 * We're either using the free space tree or no caching at all.
672 * Set cached to the appropriate value and wakeup any waiters.
674 spin_lock(&cache
->lock
);
675 if (load_cache_only
) {
676 cache
->caching_ctl
= NULL
;
677 cache
->cached
= BTRFS_CACHE_NO
;
679 cache
->cached
= BTRFS_CACHE_STARTED
;
680 cache
->has_caching_ctl
= 1;
682 spin_unlock(&cache
->lock
);
683 wake_up(&caching_ctl
->wait
);
686 if (load_cache_only
) {
687 put_caching_control(caching_ctl
);
691 down_write(&fs_info
->commit_root_sem
);
692 refcount_inc(&caching_ctl
->count
);
693 list_add_tail(&caching_ctl
->list
, &fs_info
->caching_block_groups
);
694 up_write(&fs_info
->commit_root_sem
);
696 btrfs_get_block_group(cache
);
698 btrfs_queue_work(fs_info
->caching_workers
, &caching_ctl
->work
);
704 * return the block group that starts at or after bytenr
706 static struct btrfs_block_group_cache
*
707 btrfs_lookup_first_block_group(struct btrfs_fs_info
*info
, u64 bytenr
)
709 return block_group_cache_tree_search(info
, bytenr
, 0);
713 * return the block group that contains the given bytenr
715 struct btrfs_block_group_cache
*btrfs_lookup_block_group(
716 struct btrfs_fs_info
*info
,
719 return block_group_cache_tree_search(info
, bytenr
, 1);
722 static struct btrfs_space_info
*__find_space_info(struct btrfs_fs_info
*info
,
725 struct list_head
*head
= &info
->space_info
;
726 struct btrfs_space_info
*found
;
728 flags
&= BTRFS_BLOCK_GROUP_TYPE_MASK
;
731 list_for_each_entry_rcu(found
, head
, list
) {
732 if (found
->flags
& flags
) {
741 static void add_pinned_bytes(struct btrfs_fs_info
*fs_info
, s64 num_bytes
,
742 bool metadata
, u64 root_objectid
)
744 struct btrfs_space_info
*space_info
;
748 if (root_objectid
== BTRFS_CHUNK_TREE_OBJECTID
)
749 flags
= BTRFS_BLOCK_GROUP_SYSTEM
;
751 flags
= BTRFS_BLOCK_GROUP_METADATA
;
753 flags
= BTRFS_BLOCK_GROUP_DATA
;
756 space_info
= __find_space_info(fs_info
, flags
);
758 percpu_counter_add_batch(&space_info
->total_bytes_pinned
, num_bytes
,
759 BTRFS_TOTAL_BYTES_PINNED_BATCH
);
763 * after adding space to the filesystem, we need to clear the full flags
764 * on all the space infos.
766 void btrfs_clear_space_info_full(struct btrfs_fs_info
*info
)
768 struct list_head
*head
= &info
->space_info
;
769 struct btrfs_space_info
*found
;
772 list_for_each_entry_rcu(found
, head
, list
)
777 /* simple helper to search for an existing data extent at a given offset */
778 int btrfs_lookup_data_extent(struct btrfs_fs_info
*fs_info
, u64 start
, u64 len
)
781 struct btrfs_key key
;
782 struct btrfs_path
*path
;
784 path
= btrfs_alloc_path();
788 key
.objectid
= start
;
790 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
791 ret
= btrfs_search_slot(NULL
, fs_info
->extent_root
, &key
, path
, 0, 0);
792 btrfs_free_path(path
);
797 * helper function to lookup reference count and flags of a tree block.
799 * the head node for delayed ref is used to store the sum of all the
800 * reference count modifications queued up in the rbtree. the head
801 * node may also store the extent flags to set. This way you can check
802 * to see what the reference count and extent flags would be if all of
803 * the delayed refs are not processed.
805 int btrfs_lookup_extent_info(struct btrfs_trans_handle
*trans
,
806 struct btrfs_fs_info
*fs_info
, u64 bytenr
,
807 u64 offset
, int metadata
, u64
*refs
, u64
*flags
)
809 struct btrfs_delayed_ref_head
*head
;
810 struct btrfs_delayed_ref_root
*delayed_refs
;
811 struct btrfs_path
*path
;
812 struct btrfs_extent_item
*ei
;
813 struct extent_buffer
*leaf
;
814 struct btrfs_key key
;
821 * If we don't have skinny metadata, don't bother doing anything
824 if (metadata
&& !btrfs_fs_incompat(fs_info
, SKINNY_METADATA
)) {
825 offset
= fs_info
->nodesize
;
829 path
= btrfs_alloc_path();
834 path
->skip_locking
= 1;
835 path
->search_commit_root
= 1;
839 key
.objectid
= bytenr
;
842 key
.type
= BTRFS_METADATA_ITEM_KEY
;
844 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
846 ret
= btrfs_search_slot(trans
, fs_info
->extent_root
, &key
, path
, 0, 0);
850 if (ret
> 0 && metadata
&& key
.type
== BTRFS_METADATA_ITEM_KEY
) {
851 if (path
->slots
[0]) {
853 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
855 if (key
.objectid
== bytenr
&&
856 key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
857 key
.offset
== fs_info
->nodesize
)
863 leaf
= path
->nodes
[0];
864 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
865 if (item_size
>= sizeof(*ei
)) {
866 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
867 struct btrfs_extent_item
);
868 num_refs
= btrfs_extent_refs(leaf
, ei
);
869 extent_flags
= btrfs_extent_flags(leaf
, ei
);
872 btrfs_print_v0_err(fs_info
);
874 btrfs_abort_transaction(trans
, ret
);
876 btrfs_handle_fs_error(fs_info
, ret
, NULL
);
881 BUG_ON(num_refs
== 0);
891 delayed_refs
= &trans
->transaction
->delayed_refs
;
892 spin_lock(&delayed_refs
->lock
);
893 head
= btrfs_find_delayed_ref_head(delayed_refs
, bytenr
);
895 if (!mutex_trylock(&head
->mutex
)) {
896 refcount_inc(&head
->refs
);
897 spin_unlock(&delayed_refs
->lock
);
899 btrfs_release_path(path
);
902 * Mutex was contended, block until it's released and try
905 mutex_lock(&head
->mutex
);
906 mutex_unlock(&head
->mutex
);
907 btrfs_put_delayed_ref_head(head
);
910 spin_lock(&head
->lock
);
911 if (head
->extent_op
&& head
->extent_op
->update_flags
)
912 extent_flags
|= head
->extent_op
->flags_to_set
;
914 BUG_ON(num_refs
== 0);
916 num_refs
+= head
->ref_mod
;
917 spin_unlock(&head
->lock
);
918 mutex_unlock(&head
->mutex
);
920 spin_unlock(&delayed_refs
->lock
);
922 WARN_ON(num_refs
== 0);
926 *flags
= extent_flags
;
928 btrfs_free_path(path
);
933 * Back reference rules. Back refs have three main goals:
935 * 1) differentiate between all holders of references to an extent so that
936 * when a reference is dropped we can make sure it was a valid reference
937 * before freeing the extent.
939 * 2) Provide enough information to quickly find the holders of an extent
940 * if we notice a given block is corrupted or bad.
942 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
943 * maintenance. This is actually the same as #2, but with a slightly
944 * different use case.
946 * There are two kinds of back refs. The implicit back refs is optimized
947 * for pointers in non-shared tree blocks. For a given pointer in a block,
948 * back refs of this kind provide information about the block's owner tree
949 * and the pointer's key. These information allow us to find the block by
950 * b-tree searching. The full back refs is for pointers in tree blocks not
951 * referenced by their owner trees. The location of tree block is recorded
952 * in the back refs. Actually the full back refs is generic, and can be
953 * used in all cases the implicit back refs is used. The major shortcoming
954 * of the full back refs is its overhead. Every time a tree block gets
955 * COWed, we have to update back refs entry for all pointers in it.
957 * For a newly allocated tree block, we use implicit back refs for
958 * pointers in it. This means most tree related operations only involve
959 * implicit back refs. For a tree block created in old transaction, the
960 * only way to drop a reference to it is COW it. So we can detect the
961 * event that tree block loses its owner tree's reference and do the
962 * back refs conversion.
964 * When a tree block is COWed through a tree, there are four cases:
966 * The reference count of the block is one and the tree is the block's
967 * owner tree. Nothing to do in this case.
969 * The reference count of the block is one and the tree is not the
970 * block's owner tree. In this case, full back refs is used for pointers
971 * in the block. Remove these full back refs, add implicit back refs for
972 * every pointers in the new block.
974 * The reference count of the block is greater than one and the tree is
975 * the block's owner tree. In this case, implicit back refs is used for
976 * pointers in the block. Add full back refs for every pointers in the
977 * block, increase lower level extents' reference counts. The original
978 * implicit back refs are entailed to the new block.
980 * The reference count of the block is greater than one and the tree is
981 * not the block's owner tree. Add implicit back refs for every pointer in
982 * the new block, increase lower level extents' reference count.
984 * Back Reference Key composing:
986 * The key objectid corresponds to the first byte in the extent,
987 * The key type is used to differentiate between types of back refs.
988 * There are different meanings of the key offset for different types
991 * File extents can be referenced by:
993 * - multiple snapshots, subvolumes, or different generations in one subvol
994 * - different files inside a single subvolume
995 * - different offsets inside a file (bookend extents in file.c)
997 * The extent ref structure for the implicit back refs has fields for:
999 * - Objectid of the subvolume root
1000 * - objectid of the file holding the reference
1001 * - original offset in the file
1002 * - how many bookend extents
1004 * The key offset for the implicit back refs is hash of the first
1007 * The extent ref structure for the full back refs has field for:
1009 * - number of pointers in the tree leaf
1011 * The key offset for the implicit back refs is the first byte of
1014 * When a file extent is allocated, The implicit back refs is used.
1015 * the fields are filled in:
1017 * (root_key.objectid, inode objectid, offset in file, 1)
1019 * When a file extent is removed file truncation, we find the
1020 * corresponding implicit back refs and check the following fields:
1022 * (btrfs_header_owner(leaf), inode objectid, offset in file)
1024 * Btree extents can be referenced by:
1026 * - Different subvolumes
1028 * Both the implicit back refs and the full back refs for tree blocks
1029 * only consist of key. The key offset for the implicit back refs is
1030 * objectid of block's owner tree. The key offset for the full back refs
1031 * is the first byte of parent block.
1033 * When implicit back refs is used, information about the lowest key and
1034 * level of the tree block are required. These information are stored in
1035 * tree block info structure.
1039 * is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required,
1040 * is_data == BTRFS_REF_TYPE_DATA, data type is requried,
1041 * is_data == BTRFS_REF_TYPE_ANY, either type is OK.
1043 int btrfs_get_extent_inline_ref_type(const struct extent_buffer
*eb
,
1044 struct btrfs_extent_inline_ref
*iref
,
1045 enum btrfs_inline_ref_type is_data
)
1047 int type
= btrfs_extent_inline_ref_type(eb
, iref
);
1048 u64 offset
= btrfs_extent_inline_ref_offset(eb
, iref
);
1050 if (type
== BTRFS_TREE_BLOCK_REF_KEY
||
1051 type
== BTRFS_SHARED_BLOCK_REF_KEY
||
1052 type
== BTRFS_SHARED_DATA_REF_KEY
||
1053 type
== BTRFS_EXTENT_DATA_REF_KEY
) {
1054 if (is_data
== BTRFS_REF_TYPE_BLOCK
) {
1055 if (type
== BTRFS_TREE_BLOCK_REF_KEY
)
1057 if (type
== BTRFS_SHARED_BLOCK_REF_KEY
) {
1058 ASSERT(eb
->fs_info
);
1060 * Every shared one has parent tree
1061 * block, which must be aligned to
1065 IS_ALIGNED(offset
, eb
->fs_info
->nodesize
))
1068 } else if (is_data
== BTRFS_REF_TYPE_DATA
) {
1069 if (type
== BTRFS_EXTENT_DATA_REF_KEY
)
1071 if (type
== BTRFS_SHARED_DATA_REF_KEY
) {
1072 ASSERT(eb
->fs_info
);
1074 * Every shared one has parent tree
1075 * block, which must be aligned to
1079 IS_ALIGNED(offset
, eb
->fs_info
->nodesize
))
1083 ASSERT(is_data
== BTRFS_REF_TYPE_ANY
);
1088 btrfs_print_leaf((struct extent_buffer
*)eb
);
1089 btrfs_err(eb
->fs_info
, "eb %llu invalid extent inline ref type %d",
1093 return BTRFS_REF_TYPE_INVALID
;
1096 static u64
hash_extent_data_ref(u64 root_objectid
, u64 owner
, u64 offset
)
1098 u32 high_crc
= ~(u32
)0;
1099 u32 low_crc
= ~(u32
)0;
1102 lenum
= cpu_to_le64(root_objectid
);
1103 high_crc
= crc32c(high_crc
, &lenum
, sizeof(lenum
));
1104 lenum
= cpu_to_le64(owner
);
1105 low_crc
= crc32c(low_crc
, &lenum
, sizeof(lenum
));
1106 lenum
= cpu_to_le64(offset
);
1107 low_crc
= crc32c(low_crc
, &lenum
, sizeof(lenum
));
1109 return ((u64
)high_crc
<< 31) ^ (u64
)low_crc
;
1112 static u64
hash_extent_data_ref_item(struct extent_buffer
*leaf
,
1113 struct btrfs_extent_data_ref
*ref
)
1115 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf
, ref
),
1116 btrfs_extent_data_ref_objectid(leaf
, ref
),
1117 btrfs_extent_data_ref_offset(leaf
, ref
));
1120 static int match_extent_data_ref(struct extent_buffer
*leaf
,
1121 struct btrfs_extent_data_ref
*ref
,
1122 u64 root_objectid
, u64 owner
, u64 offset
)
1124 if (btrfs_extent_data_ref_root(leaf
, ref
) != root_objectid
||
1125 btrfs_extent_data_ref_objectid(leaf
, ref
) != owner
||
1126 btrfs_extent_data_ref_offset(leaf
, ref
) != offset
)
1131 static noinline
int lookup_extent_data_ref(struct btrfs_trans_handle
*trans
,
1132 struct btrfs_path
*path
,
1133 u64 bytenr
, u64 parent
,
1135 u64 owner
, u64 offset
)
1137 struct btrfs_root
*root
= trans
->fs_info
->extent_root
;
1138 struct btrfs_key key
;
1139 struct btrfs_extent_data_ref
*ref
;
1140 struct extent_buffer
*leaf
;
1146 key
.objectid
= bytenr
;
1148 key
.type
= BTRFS_SHARED_DATA_REF_KEY
;
1149 key
.offset
= parent
;
1151 key
.type
= BTRFS_EXTENT_DATA_REF_KEY
;
1152 key
.offset
= hash_extent_data_ref(root_objectid
,
1157 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1169 leaf
= path
->nodes
[0];
1170 nritems
= btrfs_header_nritems(leaf
);
1172 if (path
->slots
[0] >= nritems
) {
1173 ret
= btrfs_next_leaf(root
, path
);
1179 leaf
= path
->nodes
[0];
1180 nritems
= btrfs_header_nritems(leaf
);
1184 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1185 if (key
.objectid
!= bytenr
||
1186 key
.type
!= BTRFS_EXTENT_DATA_REF_KEY
)
1189 ref
= btrfs_item_ptr(leaf
, path
->slots
[0],
1190 struct btrfs_extent_data_ref
);
1192 if (match_extent_data_ref(leaf
, ref
, root_objectid
,
1195 btrfs_release_path(path
);
1207 static noinline
int insert_extent_data_ref(struct btrfs_trans_handle
*trans
,
1208 struct btrfs_path
*path
,
1209 u64 bytenr
, u64 parent
,
1210 u64 root_objectid
, u64 owner
,
1211 u64 offset
, int refs_to_add
)
1213 struct btrfs_root
*root
= trans
->fs_info
->extent_root
;
1214 struct btrfs_key key
;
1215 struct extent_buffer
*leaf
;
1220 key
.objectid
= bytenr
;
1222 key
.type
= BTRFS_SHARED_DATA_REF_KEY
;
1223 key
.offset
= parent
;
1224 size
= sizeof(struct btrfs_shared_data_ref
);
1226 key
.type
= BTRFS_EXTENT_DATA_REF_KEY
;
1227 key
.offset
= hash_extent_data_ref(root_objectid
,
1229 size
= sizeof(struct btrfs_extent_data_ref
);
1232 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
, size
);
1233 if (ret
&& ret
!= -EEXIST
)
1236 leaf
= path
->nodes
[0];
1238 struct btrfs_shared_data_ref
*ref
;
1239 ref
= btrfs_item_ptr(leaf
, path
->slots
[0],
1240 struct btrfs_shared_data_ref
);
1242 btrfs_set_shared_data_ref_count(leaf
, ref
, refs_to_add
);
1244 num_refs
= btrfs_shared_data_ref_count(leaf
, ref
);
1245 num_refs
+= refs_to_add
;
1246 btrfs_set_shared_data_ref_count(leaf
, ref
, num_refs
);
1249 struct btrfs_extent_data_ref
*ref
;
1250 while (ret
== -EEXIST
) {
1251 ref
= btrfs_item_ptr(leaf
, path
->slots
[0],
1252 struct btrfs_extent_data_ref
);
1253 if (match_extent_data_ref(leaf
, ref
, root_objectid
,
1256 btrfs_release_path(path
);
1258 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
1260 if (ret
&& ret
!= -EEXIST
)
1263 leaf
= path
->nodes
[0];
1265 ref
= btrfs_item_ptr(leaf
, path
->slots
[0],
1266 struct btrfs_extent_data_ref
);
1268 btrfs_set_extent_data_ref_root(leaf
, ref
,
1270 btrfs_set_extent_data_ref_objectid(leaf
, ref
, owner
);
1271 btrfs_set_extent_data_ref_offset(leaf
, ref
, offset
);
1272 btrfs_set_extent_data_ref_count(leaf
, ref
, refs_to_add
);
1274 num_refs
= btrfs_extent_data_ref_count(leaf
, ref
);
1275 num_refs
+= refs_to_add
;
1276 btrfs_set_extent_data_ref_count(leaf
, ref
, num_refs
);
1279 btrfs_mark_buffer_dirty(leaf
);
1282 btrfs_release_path(path
);
1286 static noinline
int remove_extent_data_ref(struct btrfs_trans_handle
*trans
,
1287 struct btrfs_path
*path
,
1288 int refs_to_drop
, int *last_ref
)
1290 struct btrfs_key key
;
1291 struct btrfs_extent_data_ref
*ref1
= NULL
;
1292 struct btrfs_shared_data_ref
*ref2
= NULL
;
1293 struct extent_buffer
*leaf
;
1297 leaf
= path
->nodes
[0];
1298 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1300 if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
1301 ref1
= btrfs_item_ptr(leaf
, path
->slots
[0],
1302 struct btrfs_extent_data_ref
);
1303 num_refs
= btrfs_extent_data_ref_count(leaf
, ref1
);
1304 } else if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
1305 ref2
= btrfs_item_ptr(leaf
, path
->slots
[0],
1306 struct btrfs_shared_data_ref
);
1307 num_refs
= btrfs_shared_data_ref_count(leaf
, ref2
);
1308 } else if (unlikely(key
.type
== BTRFS_EXTENT_REF_V0_KEY
)) {
1309 btrfs_print_v0_err(trans
->fs_info
);
1310 btrfs_abort_transaction(trans
, -EINVAL
);
1316 BUG_ON(num_refs
< refs_to_drop
);
1317 num_refs
-= refs_to_drop
;
1319 if (num_refs
== 0) {
1320 ret
= btrfs_del_item(trans
, trans
->fs_info
->extent_root
, path
);
1323 if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
)
1324 btrfs_set_extent_data_ref_count(leaf
, ref1
, num_refs
);
1325 else if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
)
1326 btrfs_set_shared_data_ref_count(leaf
, ref2
, num_refs
);
1327 btrfs_mark_buffer_dirty(leaf
);
1332 static noinline u32
extent_data_ref_count(struct btrfs_path
*path
,
1333 struct btrfs_extent_inline_ref
*iref
)
1335 struct btrfs_key key
;
1336 struct extent_buffer
*leaf
;
1337 struct btrfs_extent_data_ref
*ref1
;
1338 struct btrfs_shared_data_ref
*ref2
;
1342 leaf
= path
->nodes
[0];
1343 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1345 BUG_ON(key
.type
== BTRFS_EXTENT_REF_V0_KEY
);
1348 * If type is invalid, we should have bailed out earlier than
1351 type
= btrfs_get_extent_inline_ref_type(leaf
, iref
, BTRFS_REF_TYPE_DATA
);
1352 ASSERT(type
!= BTRFS_REF_TYPE_INVALID
);
1353 if (type
== BTRFS_EXTENT_DATA_REF_KEY
) {
1354 ref1
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
1355 num_refs
= btrfs_extent_data_ref_count(leaf
, ref1
);
1357 ref2
= (struct btrfs_shared_data_ref
*)(iref
+ 1);
1358 num_refs
= btrfs_shared_data_ref_count(leaf
, ref2
);
1360 } else if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
1361 ref1
= btrfs_item_ptr(leaf
, path
->slots
[0],
1362 struct btrfs_extent_data_ref
);
1363 num_refs
= btrfs_extent_data_ref_count(leaf
, ref1
);
1364 } else if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
1365 ref2
= btrfs_item_ptr(leaf
, path
->slots
[0],
1366 struct btrfs_shared_data_ref
);
1367 num_refs
= btrfs_shared_data_ref_count(leaf
, ref2
);
1374 static noinline
int lookup_tree_block_ref(struct btrfs_trans_handle
*trans
,
1375 struct btrfs_path
*path
,
1376 u64 bytenr
, u64 parent
,
1379 struct btrfs_root
*root
= trans
->fs_info
->extent_root
;
1380 struct btrfs_key key
;
1383 key
.objectid
= bytenr
;
1385 key
.type
= BTRFS_SHARED_BLOCK_REF_KEY
;
1386 key
.offset
= parent
;
1388 key
.type
= BTRFS_TREE_BLOCK_REF_KEY
;
1389 key
.offset
= root_objectid
;
1392 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1398 static noinline
int insert_tree_block_ref(struct btrfs_trans_handle
*trans
,
1399 struct btrfs_path
*path
,
1400 u64 bytenr
, u64 parent
,
1403 struct btrfs_key key
;
1406 key
.objectid
= bytenr
;
1408 key
.type
= BTRFS_SHARED_BLOCK_REF_KEY
;
1409 key
.offset
= parent
;
1411 key
.type
= BTRFS_TREE_BLOCK_REF_KEY
;
1412 key
.offset
= root_objectid
;
1415 ret
= btrfs_insert_empty_item(trans
, trans
->fs_info
->extent_root
,
1417 btrfs_release_path(path
);
1421 static inline int extent_ref_type(u64 parent
, u64 owner
)
1424 if (owner
< BTRFS_FIRST_FREE_OBJECTID
) {
1426 type
= BTRFS_SHARED_BLOCK_REF_KEY
;
1428 type
= BTRFS_TREE_BLOCK_REF_KEY
;
1431 type
= BTRFS_SHARED_DATA_REF_KEY
;
1433 type
= BTRFS_EXTENT_DATA_REF_KEY
;
1438 static int find_next_key(struct btrfs_path
*path
, int level
,
1439 struct btrfs_key
*key
)
1442 for (; level
< BTRFS_MAX_LEVEL
; level
++) {
1443 if (!path
->nodes
[level
])
1445 if (path
->slots
[level
] + 1 >=
1446 btrfs_header_nritems(path
->nodes
[level
]))
1449 btrfs_item_key_to_cpu(path
->nodes
[level
], key
,
1450 path
->slots
[level
] + 1);
1452 btrfs_node_key_to_cpu(path
->nodes
[level
], key
,
1453 path
->slots
[level
] + 1);
1460 * look for inline back ref. if back ref is found, *ref_ret is set
1461 * to the address of inline back ref, and 0 is returned.
1463 * if back ref isn't found, *ref_ret is set to the address where it
1464 * should be inserted, and -ENOENT is returned.
1466 * if insert is true and there are too many inline back refs, the path
1467 * points to the extent item, and -EAGAIN is returned.
1469 * NOTE: inline back refs are ordered in the same way that back ref
1470 * items in the tree are ordered.
1472 static noinline_for_stack
1473 int lookup_inline_extent_backref(struct btrfs_trans_handle
*trans
,
1474 struct btrfs_path
*path
,
1475 struct btrfs_extent_inline_ref
**ref_ret
,
1476 u64 bytenr
, u64 num_bytes
,
1477 u64 parent
, u64 root_objectid
,
1478 u64 owner
, u64 offset
, int insert
)
1480 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
1481 struct btrfs_root
*root
= fs_info
->extent_root
;
1482 struct btrfs_key key
;
1483 struct extent_buffer
*leaf
;
1484 struct btrfs_extent_item
*ei
;
1485 struct btrfs_extent_inline_ref
*iref
;
1495 bool skinny_metadata
= btrfs_fs_incompat(fs_info
, SKINNY_METADATA
);
1498 key
.objectid
= bytenr
;
1499 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
1500 key
.offset
= num_bytes
;
1502 want
= extent_ref_type(parent
, owner
);
1504 extra_size
= btrfs_extent_inline_ref_size(want
);
1505 path
->keep_locks
= 1;
1510 * Owner is our level, so we can just add one to get the level for the
1511 * block we are interested in.
1513 if (skinny_metadata
&& owner
< BTRFS_FIRST_FREE_OBJECTID
) {
1514 key
.type
= BTRFS_METADATA_ITEM_KEY
;
1519 ret
= btrfs_search_slot(trans
, root
, &key
, path
, extra_size
, 1);
1526 * We may be a newly converted file system which still has the old fat
1527 * extent entries for metadata, so try and see if we have one of those.
1529 if (ret
> 0 && skinny_metadata
) {
1530 skinny_metadata
= false;
1531 if (path
->slots
[0]) {
1533 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
1535 if (key
.objectid
== bytenr
&&
1536 key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
1537 key
.offset
== num_bytes
)
1541 key
.objectid
= bytenr
;
1542 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
1543 key
.offset
= num_bytes
;
1544 btrfs_release_path(path
);
1549 if (ret
&& !insert
) {
1552 } else if (WARN_ON(ret
)) {
1557 leaf
= path
->nodes
[0];
1558 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
1559 if (unlikely(item_size
< sizeof(*ei
))) {
1561 btrfs_print_v0_err(fs_info
);
1562 btrfs_abort_transaction(trans
, err
);
1566 ei
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_extent_item
);
1567 flags
= btrfs_extent_flags(leaf
, ei
);
1569 ptr
= (unsigned long)(ei
+ 1);
1570 end
= (unsigned long)ei
+ item_size
;
1572 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
&& !skinny_metadata
) {
1573 ptr
+= sizeof(struct btrfs_tree_block_info
);
1577 if (owner
>= BTRFS_FIRST_FREE_OBJECTID
)
1578 needed
= BTRFS_REF_TYPE_DATA
;
1580 needed
= BTRFS_REF_TYPE_BLOCK
;
1588 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
1589 type
= btrfs_get_extent_inline_ref_type(leaf
, iref
, needed
);
1590 if (type
== BTRFS_REF_TYPE_INVALID
) {
1598 ptr
+= btrfs_extent_inline_ref_size(type
);
1602 if (type
== BTRFS_EXTENT_DATA_REF_KEY
) {
1603 struct btrfs_extent_data_ref
*dref
;
1604 dref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
1605 if (match_extent_data_ref(leaf
, dref
, root_objectid
,
1610 if (hash_extent_data_ref_item(leaf
, dref
) <
1611 hash_extent_data_ref(root_objectid
, owner
, offset
))
1615 ref_offset
= btrfs_extent_inline_ref_offset(leaf
, iref
);
1617 if (parent
== ref_offset
) {
1621 if (ref_offset
< parent
)
1624 if (root_objectid
== ref_offset
) {
1628 if (ref_offset
< root_objectid
)
1632 ptr
+= btrfs_extent_inline_ref_size(type
);
1634 if (err
== -ENOENT
&& insert
) {
1635 if (item_size
+ extra_size
>=
1636 BTRFS_MAX_EXTENT_ITEM_SIZE(root
)) {
1641 * To add new inline back ref, we have to make sure
1642 * there is no corresponding back ref item.
1643 * For simplicity, we just do not add new inline back
1644 * ref if there is any kind of item for this block
1646 if (find_next_key(path
, 0, &key
) == 0 &&
1647 key
.objectid
== bytenr
&&
1648 key
.type
< BTRFS_BLOCK_GROUP_ITEM_KEY
) {
1653 *ref_ret
= (struct btrfs_extent_inline_ref
*)ptr
;
1656 path
->keep_locks
= 0;
1657 btrfs_unlock_up_safe(path
, 1);
1663 * helper to add new inline back ref
1665 static noinline_for_stack
1666 void setup_inline_extent_backref(struct btrfs_fs_info
*fs_info
,
1667 struct btrfs_path
*path
,
1668 struct btrfs_extent_inline_ref
*iref
,
1669 u64 parent
, u64 root_objectid
,
1670 u64 owner
, u64 offset
, int refs_to_add
,
1671 struct btrfs_delayed_extent_op
*extent_op
)
1673 struct extent_buffer
*leaf
;
1674 struct btrfs_extent_item
*ei
;
1677 unsigned long item_offset
;
1682 leaf
= path
->nodes
[0];
1683 ei
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_extent_item
);
1684 item_offset
= (unsigned long)iref
- (unsigned long)ei
;
1686 type
= extent_ref_type(parent
, owner
);
1687 size
= btrfs_extent_inline_ref_size(type
);
1689 btrfs_extend_item(fs_info
, path
, size
);
1691 ei
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_extent_item
);
1692 refs
= btrfs_extent_refs(leaf
, ei
);
1693 refs
+= refs_to_add
;
1694 btrfs_set_extent_refs(leaf
, ei
, refs
);
1696 __run_delayed_extent_op(extent_op
, leaf
, ei
);
1698 ptr
= (unsigned long)ei
+ item_offset
;
1699 end
= (unsigned long)ei
+ btrfs_item_size_nr(leaf
, path
->slots
[0]);
1700 if (ptr
< end
- size
)
1701 memmove_extent_buffer(leaf
, ptr
+ size
, ptr
,
1704 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
1705 btrfs_set_extent_inline_ref_type(leaf
, iref
, type
);
1706 if (type
== BTRFS_EXTENT_DATA_REF_KEY
) {
1707 struct btrfs_extent_data_ref
*dref
;
1708 dref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
1709 btrfs_set_extent_data_ref_root(leaf
, dref
, root_objectid
);
1710 btrfs_set_extent_data_ref_objectid(leaf
, dref
, owner
);
1711 btrfs_set_extent_data_ref_offset(leaf
, dref
, offset
);
1712 btrfs_set_extent_data_ref_count(leaf
, dref
, refs_to_add
);
1713 } else if (type
== BTRFS_SHARED_DATA_REF_KEY
) {
1714 struct btrfs_shared_data_ref
*sref
;
1715 sref
= (struct btrfs_shared_data_ref
*)(iref
+ 1);
1716 btrfs_set_shared_data_ref_count(leaf
, sref
, refs_to_add
);
1717 btrfs_set_extent_inline_ref_offset(leaf
, iref
, parent
);
1718 } else if (type
== BTRFS_SHARED_BLOCK_REF_KEY
) {
1719 btrfs_set_extent_inline_ref_offset(leaf
, iref
, parent
);
1721 btrfs_set_extent_inline_ref_offset(leaf
, iref
, root_objectid
);
1723 btrfs_mark_buffer_dirty(leaf
);
1726 static int lookup_extent_backref(struct btrfs_trans_handle
*trans
,
1727 struct btrfs_path
*path
,
1728 struct btrfs_extent_inline_ref
**ref_ret
,
1729 u64 bytenr
, u64 num_bytes
, u64 parent
,
1730 u64 root_objectid
, u64 owner
, u64 offset
)
1734 ret
= lookup_inline_extent_backref(trans
, path
, ref_ret
, bytenr
,
1735 num_bytes
, parent
, root_objectid
,
1740 btrfs_release_path(path
);
1743 if (owner
< BTRFS_FIRST_FREE_OBJECTID
) {
1744 ret
= lookup_tree_block_ref(trans
, path
, bytenr
, parent
,
1747 ret
= lookup_extent_data_ref(trans
, path
, bytenr
, parent
,
1748 root_objectid
, owner
, offset
);
1754 * helper to update/remove inline back ref
1756 static noinline_for_stack
1757 void update_inline_extent_backref(struct btrfs_path
*path
,
1758 struct btrfs_extent_inline_ref
*iref
,
1760 struct btrfs_delayed_extent_op
*extent_op
,
1763 struct extent_buffer
*leaf
= path
->nodes
[0];
1764 struct btrfs_fs_info
*fs_info
= leaf
->fs_info
;
1765 struct btrfs_extent_item
*ei
;
1766 struct btrfs_extent_data_ref
*dref
= NULL
;
1767 struct btrfs_shared_data_ref
*sref
= NULL
;
1775 ei
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_extent_item
);
1776 refs
= btrfs_extent_refs(leaf
, ei
);
1777 WARN_ON(refs_to_mod
< 0 && refs
+ refs_to_mod
<= 0);
1778 refs
+= refs_to_mod
;
1779 btrfs_set_extent_refs(leaf
, ei
, refs
);
1781 __run_delayed_extent_op(extent_op
, leaf
, ei
);
1784 * If type is invalid, we should have bailed out after
1785 * lookup_inline_extent_backref().
1787 type
= btrfs_get_extent_inline_ref_type(leaf
, iref
, BTRFS_REF_TYPE_ANY
);
1788 ASSERT(type
!= BTRFS_REF_TYPE_INVALID
);
1790 if (type
== BTRFS_EXTENT_DATA_REF_KEY
) {
1791 dref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
1792 refs
= btrfs_extent_data_ref_count(leaf
, dref
);
1793 } else if (type
== BTRFS_SHARED_DATA_REF_KEY
) {
1794 sref
= (struct btrfs_shared_data_ref
*)(iref
+ 1);
1795 refs
= btrfs_shared_data_ref_count(leaf
, sref
);
1798 BUG_ON(refs_to_mod
!= -1);
1801 BUG_ON(refs_to_mod
< 0 && refs
< -refs_to_mod
);
1802 refs
+= refs_to_mod
;
1805 if (type
== BTRFS_EXTENT_DATA_REF_KEY
)
1806 btrfs_set_extent_data_ref_count(leaf
, dref
, refs
);
1808 btrfs_set_shared_data_ref_count(leaf
, sref
, refs
);
1811 size
= btrfs_extent_inline_ref_size(type
);
1812 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
1813 ptr
= (unsigned long)iref
;
1814 end
= (unsigned long)ei
+ item_size
;
1815 if (ptr
+ size
< end
)
1816 memmove_extent_buffer(leaf
, ptr
, ptr
+ size
,
1819 btrfs_truncate_item(fs_info
, path
, item_size
, 1);
1821 btrfs_mark_buffer_dirty(leaf
);
1824 static noinline_for_stack
1825 int insert_inline_extent_backref(struct btrfs_trans_handle
*trans
,
1826 struct btrfs_path
*path
,
1827 u64 bytenr
, u64 num_bytes
, u64 parent
,
1828 u64 root_objectid
, u64 owner
,
1829 u64 offset
, int refs_to_add
,
1830 struct btrfs_delayed_extent_op
*extent_op
)
1832 struct btrfs_extent_inline_ref
*iref
;
1835 ret
= lookup_inline_extent_backref(trans
, path
, &iref
, bytenr
,
1836 num_bytes
, parent
, root_objectid
,
1839 BUG_ON(owner
< BTRFS_FIRST_FREE_OBJECTID
);
1840 update_inline_extent_backref(path
, iref
, refs_to_add
,
1842 } else if (ret
== -ENOENT
) {
1843 setup_inline_extent_backref(trans
->fs_info
, path
, iref
, parent
,
1844 root_objectid
, owner
, offset
,
1845 refs_to_add
, extent_op
);
1851 static int insert_extent_backref(struct btrfs_trans_handle
*trans
,
1852 struct btrfs_path
*path
,
1853 u64 bytenr
, u64 parent
, u64 root_objectid
,
1854 u64 owner
, u64 offset
, int refs_to_add
)
1857 if (owner
< BTRFS_FIRST_FREE_OBJECTID
) {
1858 BUG_ON(refs_to_add
!= 1);
1859 ret
= insert_tree_block_ref(trans
, path
, bytenr
, parent
,
1862 ret
= insert_extent_data_ref(trans
, path
, bytenr
, parent
,
1863 root_objectid
, owner
, offset
,
1869 static int remove_extent_backref(struct btrfs_trans_handle
*trans
,
1870 struct btrfs_path
*path
,
1871 struct btrfs_extent_inline_ref
*iref
,
1872 int refs_to_drop
, int is_data
, int *last_ref
)
1876 BUG_ON(!is_data
&& refs_to_drop
!= 1);
1878 update_inline_extent_backref(path
, iref
, -refs_to_drop
, NULL
,
1880 } else if (is_data
) {
1881 ret
= remove_extent_data_ref(trans
, path
, refs_to_drop
,
1885 ret
= btrfs_del_item(trans
, trans
->fs_info
->extent_root
, path
);
1890 #define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
1891 static int btrfs_issue_discard(struct block_device
*bdev
, u64 start
, u64 len
,
1892 u64
*discarded_bytes
)
1895 u64 bytes_left
, end
;
1896 u64 aligned_start
= ALIGN(start
, 1 << 9);
1898 if (WARN_ON(start
!= aligned_start
)) {
1899 len
-= aligned_start
- start
;
1900 len
= round_down(len
, 1 << 9);
1901 start
= aligned_start
;
1904 *discarded_bytes
= 0;
1912 /* Skip any superblocks on this device. */
1913 for (j
= 0; j
< BTRFS_SUPER_MIRROR_MAX
; j
++) {
1914 u64 sb_start
= btrfs_sb_offset(j
);
1915 u64 sb_end
= sb_start
+ BTRFS_SUPER_INFO_SIZE
;
1916 u64 size
= sb_start
- start
;
1918 if (!in_range(sb_start
, start
, bytes_left
) &&
1919 !in_range(sb_end
, start
, bytes_left
) &&
1920 !in_range(start
, sb_start
, BTRFS_SUPER_INFO_SIZE
))
1924 * Superblock spans beginning of range. Adjust start and
1927 if (sb_start
<= start
) {
1928 start
+= sb_end
- start
;
1933 bytes_left
= end
- start
;
1938 ret
= blkdev_issue_discard(bdev
, start
>> 9, size
>> 9,
1941 *discarded_bytes
+= size
;
1942 else if (ret
!= -EOPNOTSUPP
)
1951 bytes_left
= end
- start
;
1955 ret
= blkdev_issue_discard(bdev
, start
>> 9, bytes_left
>> 9,
1958 *discarded_bytes
+= bytes_left
;
1963 int btrfs_discard_extent(struct btrfs_fs_info
*fs_info
, u64 bytenr
,
1964 u64 num_bytes
, u64
*actual_bytes
)
1967 u64 discarded_bytes
= 0;
1968 struct btrfs_bio
*bbio
= NULL
;
1972 * Avoid races with device replace and make sure our bbio has devices
1973 * associated to its stripes that don't go away while we are discarding.
1975 btrfs_bio_counter_inc_blocked(fs_info
);
1976 /* Tell the block device(s) that the sectors can be discarded */
1977 ret
= btrfs_map_block(fs_info
, BTRFS_MAP_DISCARD
, bytenr
, &num_bytes
,
1979 /* Error condition is -ENOMEM */
1981 struct btrfs_bio_stripe
*stripe
= bbio
->stripes
;
1985 for (i
= 0; i
< bbio
->num_stripes
; i
++, stripe
++) {
1987 struct request_queue
*req_q
;
1989 if (!stripe
->dev
->bdev
) {
1990 ASSERT(btrfs_test_opt(fs_info
, DEGRADED
));
1993 req_q
= bdev_get_queue(stripe
->dev
->bdev
);
1994 if (!blk_queue_discard(req_q
))
1997 ret
= btrfs_issue_discard(stripe
->dev
->bdev
,
2002 discarded_bytes
+= bytes
;
2003 else if (ret
!= -EOPNOTSUPP
)
2004 break; /* Logic errors or -ENOMEM, or -EIO but I don't know how that could happen JDM */
2007 * Just in case we get back EOPNOTSUPP for some reason,
2008 * just ignore the return value so we don't screw up
2009 * people calling discard_extent.
2013 btrfs_put_bbio(bbio
);
2015 btrfs_bio_counter_dec(fs_info
);
2018 *actual_bytes
= discarded_bytes
;
2021 if (ret
== -EOPNOTSUPP
)
2026 /* Can return -ENOMEM */
2027 int btrfs_inc_extent_ref(struct btrfs_trans_handle
*trans
,
2028 struct btrfs_root
*root
,
2029 u64 bytenr
, u64 num_bytes
, u64 parent
,
2030 u64 root_objectid
, u64 owner
, u64 offset
)
2032 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2033 int old_ref_mod
, new_ref_mod
;
2036 BUG_ON(owner
< BTRFS_FIRST_FREE_OBJECTID
&&
2037 root_objectid
== BTRFS_TREE_LOG_OBJECTID
);
2039 btrfs_ref_tree_mod(root
, bytenr
, num_bytes
, parent
, root_objectid
,
2040 owner
, offset
, BTRFS_ADD_DELAYED_REF
);
2042 if (owner
< BTRFS_FIRST_FREE_OBJECTID
) {
2043 ret
= btrfs_add_delayed_tree_ref(trans
, bytenr
,
2045 root_objectid
, (int)owner
,
2046 BTRFS_ADD_DELAYED_REF
, NULL
,
2047 &old_ref_mod
, &new_ref_mod
);
2049 ret
= btrfs_add_delayed_data_ref(trans
, bytenr
,
2051 root_objectid
, owner
, offset
,
2052 0, BTRFS_ADD_DELAYED_REF
,
2053 &old_ref_mod
, &new_ref_mod
);
2056 if (ret
== 0 && old_ref_mod
< 0 && new_ref_mod
>= 0) {
2057 bool metadata
= owner
< BTRFS_FIRST_FREE_OBJECTID
;
2059 add_pinned_bytes(fs_info
, -num_bytes
, metadata
, root_objectid
);
2066 * __btrfs_inc_extent_ref - insert backreference for a given extent
2068 * @trans: Handle of transaction
2070 * @node: The delayed ref node used to get the bytenr/length for
2071 * extent whose references are incremented.
2073 * @parent: If this is a shared extent (BTRFS_SHARED_DATA_REF_KEY/
2074 * BTRFS_SHARED_BLOCK_REF_KEY) then it holds the logical
2075 * bytenr of the parent block. Since new extents are always
2076 * created with indirect references, this will only be the case
2077 * when relocating a shared extent. In that case, root_objectid
2078 * will be BTRFS_TREE_RELOC_OBJECTID. Otheriwse, parent must
2081 * @root_objectid: The id of the root where this modification has originated,
2082 * this can be either one of the well-known metadata trees or
2083 * the subvolume id which references this extent.
2085 * @owner: For data extents it is the inode number of the owning file.
2086 * For metadata extents this parameter holds the level in the
2087 * tree of the extent.
2089 * @offset: For metadata extents the offset is ignored and is currently
2090 * always passed as 0. For data extents it is the fileoffset
2091 * this extent belongs to.
2093 * @refs_to_add Number of references to add
2095 * @extent_op Pointer to a structure, holding information necessary when
2096 * updating a tree block's flags
2099 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle
*trans
,
2100 struct btrfs_delayed_ref_node
*node
,
2101 u64 parent
, u64 root_objectid
,
2102 u64 owner
, u64 offset
, int refs_to_add
,
2103 struct btrfs_delayed_extent_op
*extent_op
)
2105 struct btrfs_path
*path
;
2106 struct extent_buffer
*leaf
;
2107 struct btrfs_extent_item
*item
;
2108 struct btrfs_key key
;
2109 u64 bytenr
= node
->bytenr
;
2110 u64 num_bytes
= node
->num_bytes
;
2114 path
= btrfs_alloc_path();
2118 path
->reada
= READA_FORWARD
;
2119 path
->leave_spinning
= 1;
2120 /* this will setup the path even if it fails to insert the back ref */
2121 ret
= insert_inline_extent_backref(trans
, path
, bytenr
, num_bytes
,
2122 parent
, root_objectid
, owner
,
2123 offset
, refs_to_add
, extent_op
);
2124 if ((ret
< 0 && ret
!= -EAGAIN
) || !ret
)
2128 * Ok we had -EAGAIN which means we didn't have space to insert and
2129 * inline extent ref, so just update the reference count and add a
2132 leaf
= path
->nodes
[0];
2133 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
2134 item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_extent_item
);
2135 refs
= btrfs_extent_refs(leaf
, item
);
2136 btrfs_set_extent_refs(leaf
, item
, refs
+ refs_to_add
);
2138 __run_delayed_extent_op(extent_op
, leaf
, item
);
2140 btrfs_mark_buffer_dirty(leaf
);
2141 btrfs_release_path(path
);
2143 path
->reada
= READA_FORWARD
;
2144 path
->leave_spinning
= 1;
2145 /* now insert the actual backref */
2146 ret
= insert_extent_backref(trans
, path
, bytenr
, parent
, root_objectid
,
2147 owner
, offset
, refs_to_add
);
2149 btrfs_abort_transaction(trans
, ret
);
2151 btrfs_free_path(path
);
2155 static int run_delayed_data_ref(struct btrfs_trans_handle
*trans
,
2156 struct btrfs_delayed_ref_node
*node
,
2157 struct btrfs_delayed_extent_op
*extent_op
,
2158 int insert_reserved
)
2161 struct btrfs_delayed_data_ref
*ref
;
2162 struct btrfs_key ins
;
2167 ins
.objectid
= node
->bytenr
;
2168 ins
.offset
= node
->num_bytes
;
2169 ins
.type
= BTRFS_EXTENT_ITEM_KEY
;
2171 ref
= btrfs_delayed_node_to_data_ref(node
);
2172 trace_run_delayed_data_ref(trans
->fs_info
, node
, ref
, node
->action
);
2174 if (node
->type
== BTRFS_SHARED_DATA_REF_KEY
)
2175 parent
= ref
->parent
;
2176 ref_root
= ref
->root
;
2178 if (node
->action
== BTRFS_ADD_DELAYED_REF
&& insert_reserved
) {
2180 flags
|= extent_op
->flags_to_set
;
2181 ret
= alloc_reserved_file_extent(trans
, parent
, ref_root
,
2182 flags
, ref
->objectid
,
2185 } else if (node
->action
== BTRFS_ADD_DELAYED_REF
) {
2186 ret
= __btrfs_inc_extent_ref(trans
, node
, parent
, ref_root
,
2187 ref
->objectid
, ref
->offset
,
2188 node
->ref_mod
, extent_op
);
2189 } else if (node
->action
== BTRFS_DROP_DELAYED_REF
) {
2190 ret
= __btrfs_free_extent(trans
, node
, parent
,
2191 ref_root
, ref
->objectid
,
2192 ref
->offset
, node
->ref_mod
,
2200 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op
*extent_op
,
2201 struct extent_buffer
*leaf
,
2202 struct btrfs_extent_item
*ei
)
2204 u64 flags
= btrfs_extent_flags(leaf
, ei
);
2205 if (extent_op
->update_flags
) {
2206 flags
|= extent_op
->flags_to_set
;
2207 btrfs_set_extent_flags(leaf
, ei
, flags
);
2210 if (extent_op
->update_key
) {
2211 struct btrfs_tree_block_info
*bi
;
2212 BUG_ON(!(flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
));
2213 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
2214 btrfs_set_tree_block_key(leaf
, bi
, &extent_op
->key
);
2218 static int run_delayed_extent_op(struct btrfs_trans_handle
*trans
,
2219 struct btrfs_delayed_ref_head
*head
,
2220 struct btrfs_delayed_extent_op
*extent_op
)
2222 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2223 struct btrfs_key key
;
2224 struct btrfs_path
*path
;
2225 struct btrfs_extent_item
*ei
;
2226 struct extent_buffer
*leaf
;
2230 int metadata
= !extent_op
->is_data
;
2235 if (metadata
&& !btrfs_fs_incompat(fs_info
, SKINNY_METADATA
))
2238 path
= btrfs_alloc_path();
2242 key
.objectid
= head
->bytenr
;
2245 key
.type
= BTRFS_METADATA_ITEM_KEY
;
2246 key
.offset
= extent_op
->level
;
2248 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
2249 key
.offset
= head
->num_bytes
;
2253 path
->reada
= READA_FORWARD
;
2254 path
->leave_spinning
= 1;
2255 ret
= btrfs_search_slot(trans
, fs_info
->extent_root
, &key
, path
, 0, 1);
2262 if (path
->slots
[0] > 0) {
2264 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
2266 if (key
.objectid
== head
->bytenr
&&
2267 key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
2268 key
.offset
== head
->num_bytes
)
2272 btrfs_release_path(path
);
2275 key
.objectid
= head
->bytenr
;
2276 key
.offset
= head
->num_bytes
;
2277 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
2286 leaf
= path
->nodes
[0];
2287 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
2289 if (unlikely(item_size
< sizeof(*ei
))) {
2291 btrfs_print_v0_err(fs_info
);
2292 btrfs_abort_transaction(trans
, err
);
2296 ei
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_extent_item
);
2297 __run_delayed_extent_op(extent_op
, leaf
, ei
);
2299 btrfs_mark_buffer_dirty(leaf
);
2301 btrfs_free_path(path
);
2305 static int run_delayed_tree_ref(struct btrfs_trans_handle
*trans
,
2306 struct btrfs_delayed_ref_node
*node
,
2307 struct btrfs_delayed_extent_op
*extent_op
,
2308 int insert_reserved
)
2311 struct btrfs_delayed_tree_ref
*ref
;
2315 ref
= btrfs_delayed_node_to_tree_ref(node
);
2316 trace_run_delayed_tree_ref(trans
->fs_info
, node
, ref
, node
->action
);
2318 if (node
->type
== BTRFS_SHARED_BLOCK_REF_KEY
)
2319 parent
= ref
->parent
;
2320 ref_root
= ref
->root
;
2322 if (node
->ref_mod
!= 1) {
2323 btrfs_err(trans
->fs_info
,
2324 "btree block(%llu) has %d references rather than 1: action %d ref_root %llu parent %llu",
2325 node
->bytenr
, node
->ref_mod
, node
->action
, ref_root
,
2329 if (node
->action
== BTRFS_ADD_DELAYED_REF
&& insert_reserved
) {
2330 BUG_ON(!extent_op
|| !extent_op
->update_flags
);
2331 ret
= alloc_reserved_tree_block(trans
, node
, extent_op
);
2332 } else if (node
->action
== BTRFS_ADD_DELAYED_REF
) {
2333 ret
= __btrfs_inc_extent_ref(trans
, node
, parent
, ref_root
,
2334 ref
->level
, 0, 1, extent_op
);
2335 } else if (node
->action
== BTRFS_DROP_DELAYED_REF
) {
2336 ret
= __btrfs_free_extent(trans
, node
, parent
, ref_root
,
2337 ref
->level
, 0, 1, extent_op
);
2344 /* helper function to actually process a single delayed ref entry */
2345 static int run_one_delayed_ref(struct btrfs_trans_handle
*trans
,
2346 struct btrfs_delayed_ref_node
*node
,
2347 struct btrfs_delayed_extent_op
*extent_op
,
2348 int insert_reserved
)
2352 if (trans
->aborted
) {
2353 if (insert_reserved
)
2354 btrfs_pin_extent(trans
->fs_info
, node
->bytenr
,
2355 node
->num_bytes
, 1);
2359 if (node
->type
== BTRFS_TREE_BLOCK_REF_KEY
||
2360 node
->type
== BTRFS_SHARED_BLOCK_REF_KEY
)
2361 ret
= run_delayed_tree_ref(trans
, node
, extent_op
,
2363 else if (node
->type
== BTRFS_EXTENT_DATA_REF_KEY
||
2364 node
->type
== BTRFS_SHARED_DATA_REF_KEY
)
2365 ret
= run_delayed_data_ref(trans
, node
, extent_op
,
2372 static inline struct btrfs_delayed_ref_node
*
2373 select_delayed_ref(struct btrfs_delayed_ref_head
*head
)
2375 struct btrfs_delayed_ref_node
*ref
;
2377 if (RB_EMPTY_ROOT(&head
->ref_tree
.rb_root
))
2381 * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
2382 * This is to prevent a ref count from going down to zero, which deletes
2383 * the extent item from the extent tree, when there still are references
2384 * to add, which would fail because they would not find the extent item.
2386 if (!list_empty(&head
->ref_add_list
))
2387 return list_first_entry(&head
->ref_add_list
,
2388 struct btrfs_delayed_ref_node
, add_list
);
2390 ref
= rb_entry(rb_first_cached(&head
->ref_tree
),
2391 struct btrfs_delayed_ref_node
, ref_node
);
2392 ASSERT(list_empty(&ref
->add_list
));
2396 static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root
*delayed_refs
,
2397 struct btrfs_delayed_ref_head
*head
)
2399 spin_lock(&delayed_refs
->lock
);
2400 head
->processing
= 0;
2401 delayed_refs
->num_heads_ready
++;
2402 spin_unlock(&delayed_refs
->lock
);
2403 btrfs_delayed_ref_unlock(head
);
2406 static int cleanup_extent_op(struct btrfs_trans_handle
*trans
,
2407 struct btrfs_delayed_ref_head
*head
)
2409 struct btrfs_delayed_extent_op
*extent_op
= head
->extent_op
;
2414 head
->extent_op
= NULL
;
2415 if (head
->must_insert_reserved
) {
2416 btrfs_free_delayed_extent_op(extent_op
);
2419 spin_unlock(&head
->lock
);
2420 ret
= run_delayed_extent_op(trans
, head
, extent_op
);
2421 btrfs_free_delayed_extent_op(extent_op
);
2422 return ret
? ret
: 1;
2425 static int cleanup_ref_head(struct btrfs_trans_handle
*trans
,
2426 struct btrfs_delayed_ref_head
*head
)
2429 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2430 struct btrfs_delayed_ref_root
*delayed_refs
;
2433 delayed_refs
= &trans
->transaction
->delayed_refs
;
2435 ret
= cleanup_extent_op(trans
, head
);
2437 unselect_delayed_ref_head(delayed_refs
, head
);
2438 btrfs_debug(fs_info
, "run_delayed_extent_op returned %d", ret
);
2445 * Need to drop our head ref lock and re-acquire the delayed ref lock
2446 * and then re-check to make sure nobody got added.
2448 spin_unlock(&head
->lock
);
2449 spin_lock(&delayed_refs
->lock
);
2450 spin_lock(&head
->lock
);
2451 if (!RB_EMPTY_ROOT(&head
->ref_tree
.rb_root
) || head
->extent_op
) {
2452 spin_unlock(&head
->lock
);
2453 spin_unlock(&delayed_refs
->lock
);
2456 delayed_refs
->num_heads
--;
2457 rb_erase_cached(&head
->href_node
, &delayed_refs
->href_root
);
2458 RB_CLEAR_NODE(&head
->href_node
);
2459 spin_unlock(&head
->lock
);
2460 spin_unlock(&delayed_refs
->lock
);
2461 atomic_dec(&delayed_refs
->num_entries
);
2463 trace_run_delayed_ref_head(fs_info
, head
, 0);
2465 if (head
->total_ref_mod
< 0) {
2466 struct btrfs_space_info
*space_info
;
2470 flags
= BTRFS_BLOCK_GROUP_DATA
;
2471 else if (head
->is_system
)
2472 flags
= BTRFS_BLOCK_GROUP_SYSTEM
;
2474 flags
= BTRFS_BLOCK_GROUP_METADATA
;
2475 space_info
= __find_space_info(fs_info
, flags
);
2477 percpu_counter_add_batch(&space_info
->total_bytes_pinned
,
2479 BTRFS_TOTAL_BYTES_PINNED_BATCH
);
2481 if (head
->is_data
) {
2482 spin_lock(&delayed_refs
->lock
);
2483 delayed_refs
->pending_csums
-= head
->num_bytes
;
2484 spin_unlock(&delayed_refs
->lock
);
2488 if (head
->must_insert_reserved
) {
2489 btrfs_pin_extent(fs_info
, head
->bytenr
,
2490 head
->num_bytes
, 1);
2491 if (head
->is_data
) {
2492 ret
= btrfs_del_csums(trans
, fs_info
, head
->bytenr
,
2497 /* Also free its reserved qgroup space */
2498 btrfs_qgroup_free_delayed_ref(fs_info
, head
->qgroup_ref_root
,
2499 head
->qgroup_reserved
);
2500 btrfs_delayed_ref_unlock(head
);
2501 btrfs_put_delayed_ref_head(head
);
2505 static struct btrfs_delayed_ref_head
*btrfs_obtain_ref_head(
2506 struct btrfs_trans_handle
*trans
)
2508 struct btrfs_delayed_ref_root
*delayed_refs
=
2509 &trans
->transaction
->delayed_refs
;
2510 struct btrfs_delayed_ref_head
*head
= NULL
;
2513 spin_lock(&delayed_refs
->lock
);
2514 head
= btrfs_select_ref_head(delayed_refs
);
2516 spin_unlock(&delayed_refs
->lock
);
2521 * Grab the lock that says we are going to process all the refs for
2524 ret
= btrfs_delayed_ref_lock(delayed_refs
, head
);
2525 spin_unlock(&delayed_refs
->lock
);
2528 * We may have dropped the spin lock to get the head mutex lock, and
2529 * that might have given someone else time to free the head. If that's
2530 * true, it has been removed from our list and we can move on.
2533 head
= ERR_PTR(-EAGAIN
);
2538 static int btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle
*trans
,
2539 struct btrfs_delayed_ref_head
*locked_ref
,
2540 unsigned long *run_refs
)
2542 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2543 struct btrfs_delayed_ref_root
*delayed_refs
;
2544 struct btrfs_delayed_extent_op
*extent_op
;
2545 struct btrfs_delayed_ref_node
*ref
;
2546 int must_insert_reserved
= 0;
2549 delayed_refs
= &trans
->transaction
->delayed_refs
;
2551 lockdep_assert_held(&locked_ref
->mutex
);
2552 lockdep_assert_held(&locked_ref
->lock
);
2554 while ((ref
= select_delayed_ref(locked_ref
))) {
2556 btrfs_check_delayed_seq(fs_info
, ref
->seq
)) {
2557 spin_unlock(&locked_ref
->lock
);
2558 unselect_delayed_ref_head(delayed_refs
, locked_ref
);
2564 rb_erase_cached(&ref
->ref_node
, &locked_ref
->ref_tree
);
2565 RB_CLEAR_NODE(&ref
->ref_node
);
2566 if (!list_empty(&ref
->add_list
))
2567 list_del(&ref
->add_list
);
2569 * When we play the delayed ref, also correct the ref_mod on
2572 switch (ref
->action
) {
2573 case BTRFS_ADD_DELAYED_REF
:
2574 case BTRFS_ADD_DELAYED_EXTENT
:
2575 locked_ref
->ref_mod
-= ref
->ref_mod
;
2577 case BTRFS_DROP_DELAYED_REF
:
2578 locked_ref
->ref_mod
+= ref
->ref_mod
;
2583 atomic_dec(&delayed_refs
->num_entries
);
2586 * Record the must_insert_reserved flag before we drop the
2589 must_insert_reserved
= locked_ref
->must_insert_reserved
;
2590 locked_ref
->must_insert_reserved
= 0;
2592 extent_op
= locked_ref
->extent_op
;
2593 locked_ref
->extent_op
= NULL
;
2594 spin_unlock(&locked_ref
->lock
);
2596 ret
= run_one_delayed_ref(trans
, ref
, extent_op
,
2597 must_insert_reserved
);
2599 btrfs_free_delayed_extent_op(extent_op
);
2601 unselect_delayed_ref_head(delayed_refs
, locked_ref
);
2602 btrfs_put_delayed_ref(ref
);
2603 btrfs_debug(fs_info
, "run_one_delayed_ref returned %d",
2608 btrfs_put_delayed_ref(ref
);
2611 spin_lock(&locked_ref
->lock
);
2612 btrfs_merge_delayed_refs(trans
, delayed_refs
, locked_ref
);
2619 * Returns 0 on success or if called with an already aborted transaction.
2620 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
2622 static noinline
int __btrfs_run_delayed_refs(struct btrfs_trans_handle
*trans
,
2625 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2626 struct btrfs_delayed_ref_root
*delayed_refs
;
2627 struct btrfs_delayed_ref_head
*locked_ref
= NULL
;
2628 ktime_t start
= ktime_get();
2630 unsigned long count
= 0;
2631 unsigned long actual_count
= 0;
2633 delayed_refs
= &trans
->transaction
->delayed_refs
;
2636 locked_ref
= btrfs_obtain_ref_head(trans
);
2637 if (IS_ERR_OR_NULL(locked_ref
)) {
2638 if (PTR_ERR(locked_ref
) == -EAGAIN
) {
2647 * We need to try and merge add/drops of the same ref since we
2648 * can run into issues with relocate dropping the implicit ref
2649 * and then it being added back again before the drop can
2650 * finish. If we merged anything we need to re-loop so we can
2652 * Or we can get node references of the same type that weren't
2653 * merged when created due to bumps in the tree mod seq, and
2654 * we need to merge them to prevent adding an inline extent
2655 * backref before dropping it (triggering a BUG_ON at
2656 * insert_inline_extent_backref()).
2658 spin_lock(&locked_ref
->lock
);
2659 btrfs_merge_delayed_refs(trans
, delayed_refs
, locked_ref
);
2661 ret
= btrfs_run_delayed_refs_for_head(trans
, locked_ref
,
2663 if (ret
< 0 && ret
!= -EAGAIN
) {
2665 * Error, btrfs_run_delayed_refs_for_head already
2666 * unlocked everything so just bail out
2671 * Success, perform the usual cleanup of a processed
2674 ret
= cleanup_ref_head(trans
, locked_ref
);
2676 /* We dropped our lock, we need to loop. */
2685 * Either success case or btrfs_run_delayed_refs_for_head
2686 * returned -EAGAIN, meaning we need to select another head
2691 } while ((nr
!= -1 && count
< nr
) || locked_ref
);
2694 * We don't want to include ref heads since we can have empty ref heads
2695 * and those will drastically skew our runtime down since we just do
2696 * accounting, no actual extent tree updates.
2698 if (actual_count
> 0) {
2699 u64 runtime
= ktime_to_ns(ktime_sub(ktime_get(), start
));
2703 * We weigh the current average higher than our current runtime
2704 * to avoid large swings in the average.
2706 spin_lock(&delayed_refs
->lock
);
2707 avg
= fs_info
->avg_delayed_ref_runtime
* 3 + runtime
;
2708 fs_info
->avg_delayed_ref_runtime
= avg
>> 2; /* div by 4 */
2709 spin_unlock(&delayed_refs
->lock
);
2714 #ifdef SCRAMBLE_DELAYED_REFS
2716 * Normally delayed refs get processed in ascending bytenr order. This
2717 * correlates in most cases to the order added. To expose dependencies on this
2718 * order, we start to process the tree in the middle instead of the beginning
2720 static u64
find_middle(struct rb_root
*root
)
2722 struct rb_node
*n
= root
->rb_node
;
2723 struct btrfs_delayed_ref_node
*entry
;
2726 u64 first
= 0, last
= 0;
2730 entry
= rb_entry(n
, struct btrfs_delayed_ref_node
, rb_node
);
2731 first
= entry
->bytenr
;
2735 entry
= rb_entry(n
, struct btrfs_delayed_ref_node
, rb_node
);
2736 last
= entry
->bytenr
;
2741 entry
= rb_entry(n
, struct btrfs_delayed_ref_node
, rb_node
);
2742 WARN_ON(!entry
->in_tree
);
2744 middle
= entry
->bytenr
;
2757 static inline u64
heads_to_leaves(struct btrfs_fs_info
*fs_info
, u64 heads
)
2761 num_bytes
= heads
* (sizeof(struct btrfs_extent_item
) +
2762 sizeof(struct btrfs_extent_inline_ref
));
2763 if (!btrfs_fs_incompat(fs_info
, SKINNY_METADATA
))
2764 num_bytes
+= heads
* sizeof(struct btrfs_tree_block_info
);
2767 * We don't ever fill up leaves all the way so multiply by 2 just to be
2768 * closer to what we're really going to want to use.
2770 return div_u64(num_bytes
, BTRFS_LEAF_DATA_SIZE(fs_info
));
2774 * Takes the number of bytes to be csumm'ed and figures out how many leaves it
2775 * would require to store the csums for that many bytes.
2777 u64
btrfs_csum_bytes_to_leaves(struct btrfs_fs_info
*fs_info
, u64 csum_bytes
)
2780 u64 num_csums_per_leaf
;
2783 csum_size
= BTRFS_MAX_ITEM_SIZE(fs_info
);
2784 num_csums_per_leaf
= div64_u64(csum_size
,
2785 (u64
)btrfs_super_csum_size(fs_info
->super_copy
));
2786 num_csums
= div64_u64(csum_bytes
, fs_info
->sectorsize
);
2787 num_csums
+= num_csums_per_leaf
- 1;
2788 num_csums
= div64_u64(num_csums
, num_csums_per_leaf
);
2792 int btrfs_check_space_for_delayed_refs(struct btrfs_trans_handle
*trans
)
2794 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2795 struct btrfs_block_rsv
*global_rsv
;
2796 u64 num_heads
= trans
->transaction
->delayed_refs
.num_heads_ready
;
2797 u64 csum_bytes
= trans
->transaction
->delayed_refs
.pending_csums
;
2798 unsigned int num_dirty_bgs
= trans
->transaction
->num_dirty_bgs
;
2799 u64 num_bytes
, num_dirty_bgs_bytes
;
2802 num_bytes
= btrfs_calc_trans_metadata_size(fs_info
, 1);
2803 num_heads
= heads_to_leaves(fs_info
, num_heads
);
2805 num_bytes
+= (num_heads
- 1) * fs_info
->nodesize
;
2807 num_bytes
+= btrfs_csum_bytes_to_leaves(fs_info
, csum_bytes
) *
2809 num_dirty_bgs_bytes
= btrfs_calc_trans_metadata_size(fs_info
,
2811 global_rsv
= &fs_info
->global_block_rsv
;
2814 * If we can't allocate any more chunks lets make sure we have _lots_ of
2815 * wiggle room since running delayed refs can create more delayed refs.
2817 if (global_rsv
->space_info
->full
) {
2818 num_dirty_bgs_bytes
<<= 1;
2822 spin_lock(&global_rsv
->lock
);
2823 if (global_rsv
->reserved
<= num_bytes
+ num_dirty_bgs_bytes
)
2825 spin_unlock(&global_rsv
->lock
);
2829 int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle
*trans
)
2832 atomic_read(&trans
->transaction
->delayed_refs
.num_entries
);
2837 avg_runtime
= trans
->fs_info
->avg_delayed_ref_runtime
;
2838 val
= num_entries
* avg_runtime
;
2839 if (val
>= NSEC_PER_SEC
)
2841 if (val
>= NSEC_PER_SEC
/ 2)
2844 return btrfs_check_space_for_delayed_refs(trans
);
2847 struct async_delayed_refs
{
2848 struct btrfs_root
*root
;
2853 struct completion wait
;
2854 struct btrfs_work work
;
2857 static inline struct async_delayed_refs
*
2858 to_async_delayed_refs(struct btrfs_work
*work
)
2860 return container_of(work
, struct async_delayed_refs
, work
);
2863 static void delayed_ref_async_start(struct btrfs_work
*work
)
2865 struct async_delayed_refs
*async
= to_async_delayed_refs(work
);
2866 struct btrfs_trans_handle
*trans
;
2867 struct btrfs_fs_info
*fs_info
= async
->root
->fs_info
;
2870 /* if the commit is already started, we don't need to wait here */
2871 if (btrfs_transaction_blocked(fs_info
))
2874 trans
= btrfs_join_transaction(async
->root
);
2875 if (IS_ERR(trans
)) {
2876 async
->error
= PTR_ERR(trans
);
2881 * trans->sync means that when we call end_transaction, we won't
2882 * wait on delayed refs
2886 /* Don't bother flushing if we got into a different transaction */
2887 if (trans
->transid
> async
->transid
)
2890 ret
= btrfs_run_delayed_refs(trans
, async
->count
);
2894 ret
= btrfs_end_transaction(trans
);
2895 if (ret
&& !async
->error
)
2899 complete(&async
->wait
);
2904 int btrfs_async_run_delayed_refs(struct btrfs_fs_info
*fs_info
,
2905 unsigned long count
, u64 transid
, int wait
)
2907 struct async_delayed_refs
*async
;
2910 async
= kmalloc(sizeof(*async
), GFP_NOFS
);
2914 async
->root
= fs_info
->tree_root
;
2915 async
->count
= count
;
2917 async
->transid
= transid
;
2922 init_completion(&async
->wait
);
2924 btrfs_init_work(&async
->work
, btrfs_extent_refs_helper
,
2925 delayed_ref_async_start
, NULL
, NULL
);
2927 btrfs_queue_work(fs_info
->extent_workers
, &async
->work
);
2930 wait_for_completion(&async
->wait
);
2939 * this starts processing the delayed reference count updates and
2940 * extent insertions we have queued up so far. count can be
2941 * 0, which means to process everything in the tree at the start
2942 * of the run (but not newly added entries), or it can be some target
2943 * number you'd like to process.
2945 * Returns 0 on success or if called with an aborted transaction
2946 * Returns <0 on error and aborts the transaction
2948 int btrfs_run_delayed_refs(struct btrfs_trans_handle
*trans
,
2949 unsigned long count
)
2951 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2952 struct rb_node
*node
;
2953 struct btrfs_delayed_ref_root
*delayed_refs
;
2954 struct btrfs_delayed_ref_head
*head
;
2956 int run_all
= count
== (unsigned long)-1;
2957 bool can_flush_pending_bgs
= trans
->can_flush_pending_bgs
;
2959 /* We'll clean this up in btrfs_cleanup_transaction */
2963 if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE
, &fs_info
->flags
))
2966 delayed_refs
= &trans
->transaction
->delayed_refs
;
2968 count
= atomic_read(&delayed_refs
->num_entries
) * 2;
2971 #ifdef SCRAMBLE_DELAYED_REFS
2972 delayed_refs
->run_delayed_start
= find_middle(&delayed_refs
->root
);
2974 trans
->can_flush_pending_bgs
= false;
2975 ret
= __btrfs_run_delayed_refs(trans
, count
);
2977 btrfs_abort_transaction(trans
, ret
);
2982 if (!list_empty(&trans
->new_bgs
))
2983 btrfs_create_pending_block_groups(trans
);
2985 spin_lock(&delayed_refs
->lock
);
2986 node
= rb_first_cached(&delayed_refs
->href_root
);
2988 spin_unlock(&delayed_refs
->lock
);
2991 head
= rb_entry(node
, struct btrfs_delayed_ref_head
,
2993 refcount_inc(&head
->refs
);
2994 spin_unlock(&delayed_refs
->lock
);
2996 /* Mutex was contended, block until it's released and retry. */
2997 mutex_lock(&head
->mutex
);
2998 mutex_unlock(&head
->mutex
);
3000 btrfs_put_delayed_ref_head(head
);
3005 trans
->can_flush_pending_bgs
= can_flush_pending_bgs
;
3009 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle
*trans
,
3010 struct btrfs_fs_info
*fs_info
,
3011 u64 bytenr
, u64 num_bytes
, u64 flags
,
3012 int level
, int is_data
)
3014 struct btrfs_delayed_extent_op
*extent_op
;
3017 extent_op
= btrfs_alloc_delayed_extent_op();
3021 extent_op
->flags_to_set
= flags
;
3022 extent_op
->update_flags
= true;
3023 extent_op
->update_key
= false;
3024 extent_op
->is_data
= is_data
? true : false;
3025 extent_op
->level
= level
;
3027 ret
= btrfs_add_delayed_extent_op(fs_info
, trans
, bytenr
,
3028 num_bytes
, extent_op
);
3030 btrfs_free_delayed_extent_op(extent_op
);
3034 static noinline
int check_delayed_ref(struct btrfs_root
*root
,
3035 struct btrfs_path
*path
,
3036 u64 objectid
, u64 offset
, u64 bytenr
)
3038 struct btrfs_delayed_ref_head
*head
;
3039 struct btrfs_delayed_ref_node
*ref
;
3040 struct btrfs_delayed_data_ref
*data_ref
;
3041 struct btrfs_delayed_ref_root
*delayed_refs
;
3042 struct btrfs_transaction
*cur_trans
;
3043 struct rb_node
*node
;
3046 spin_lock(&root
->fs_info
->trans_lock
);
3047 cur_trans
= root
->fs_info
->running_transaction
;
3049 refcount_inc(&cur_trans
->use_count
);
3050 spin_unlock(&root
->fs_info
->trans_lock
);
3054 delayed_refs
= &cur_trans
->delayed_refs
;
3055 spin_lock(&delayed_refs
->lock
);
3056 head
= btrfs_find_delayed_ref_head(delayed_refs
, bytenr
);
3058 spin_unlock(&delayed_refs
->lock
);
3059 btrfs_put_transaction(cur_trans
);
3063 if (!mutex_trylock(&head
->mutex
)) {
3064 refcount_inc(&head
->refs
);
3065 spin_unlock(&delayed_refs
->lock
);
3067 btrfs_release_path(path
);
3070 * Mutex was contended, block until it's released and let
3073 mutex_lock(&head
->mutex
);
3074 mutex_unlock(&head
->mutex
);
3075 btrfs_put_delayed_ref_head(head
);
3076 btrfs_put_transaction(cur_trans
);
3079 spin_unlock(&delayed_refs
->lock
);
3081 spin_lock(&head
->lock
);
3083 * XXX: We should replace this with a proper search function in the
3086 for (node
= rb_first_cached(&head
->ref_tree
); node
;
3087 node
= rb_next(node
)) {
3088 ref
= rb_entry(node
, struct btrfs_delayed_ref_node
, ref_node
);
3089 /* If it's a shared ref we know a cross reference exists */
3090 if (ref
->type
!= BTRFS_EXTENT_DATA_REF_KEY
) {
3095 data_ref
= btrfs_delayed_node_to_data_ref(ref
);
3098 * If our ref doesn't match the one we're currently looking at
3099 * then we have a cross reference.
3101 if (data_ref
->root
!= root
->root_key
.objectid
||
3102 data_ref
->objectid
!= objectid
||
3103 data_ref
->offset
!= offset
) {
3108 spin_unlock(&head
->lock
);
3109 mutex_unlock(&head
->mutex
);
3110 btrfs_put_transaction(cur_trans
);
3114 static noinline
int check_committed_ref(struct btrfs_root
*root
,
3115 struct btrfs_path
*path
,
3116 u64 objectid
, u64 offset
, u64 bytenr
)
3118 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
3119 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
3120 struct extent_buffer
*leaf
;
3121 struct btrfs_extent_data_ref
*ref
;
3122 struct btrfs_extent_inline_ref
*iref
;
3123 struct btrfs_extent_item
*ei
;
3124 struct btrfs_key key
;
3129 key
.objectid
= bytenr
;
3130 key
.offset
= (u64
)-1;
3131 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
3133 ret
= btrfs_search_slot(NULL
, extent_root
, &key
, path
, 0, 0);
3136 BUG_ON(ret
== 0); /* Corruption */
3139 if (path
->slots
[0] == 0)
3143 leaf
= path
->nodes
[0];
3144 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
3146 if (key
.objectid
!= bytenr
|| key
.type
!= BTRFS_EXTENT_ITEM_KEY
)
3150 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
3151 ei
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_extent_item
);
3153 if (item_size
!= sizeof(*ei
) +
3154 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY
))
3157 if (btrfs_extent_generation(leaf
, ei
) <=
3158 btrfs_root_last_snapshot(&root
->root_item
))
3161 iref
= (struct btrfs_extent_inline_ref
*)(ei
+ 1);
3163 type
= btrfs_get_extent_inline_ref_type(leaf
, iref
, BTRFS_REF_TYPE_DATA
);
3164 if (type
!= BTRFS_EXTENT_DATA_REF_KEY
)
3167 ref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
3168 if (btrfs_extent_refs(leaf
, ei
) !=
3169 btrfs_extent_data_ref_count(leaf
, ref
) ||
3170 btrfs_extent_data_ref_root(leaf
, ref
) !=
3171 root
->root_key
.objectid
||
3172 btrfs_extent_data_ref_objectid(leaf
, ref
) != objectid
||
3173 btrfs_extent_data_ref_offset(leaf
, ref
) != offset
)
3181 int btrfs_cross_ref_exist(struct btrfs_root
*root
, u64 objectid
, u64 offset
,
3184 struct btrfs_path
*path
;
3187 path
= btrfs_alloc_path();
3192 ret
= check_committed_ref(root
, path
, objectid
,
3194 if (ret
&& ret
!= -ENOENT
)
3197 ret
= check_delayed_ref(root
, path
, objectid
, offset
, bytenr
);
3198 } while (ret
== -EAGAIN
);
3201 btrfs_free_path(path
);
3202 if (root
->root_key
.objectid
== BTRFS_DATA_RELOC_TREE_OBJECTID
)
3207 static int __btrfs_mod_ref(struct btrfs_trans_handle
*trans
,
3208 struct btrfs_root
*root
,
3209 struct extent_buffer
*buf
,
3210 int full_backref
, int inc
)
3212 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
3218 struct btrfs_key key
;
3219 struct btrfs_file_extent_item
*fi
;
3223 int (*process_func
)(struct btrfs_trans_handle
*,
3224 struct btrfs_root
*,
3225 u64
, u64
, u64
, u64
, u64
, u64
);
3228 if (btrfs_is_testing(fs_info
))
3231 ref_root
= btrfs_header_owner(buf
);
3232 nritems
= btrfs_header_nritems(buf
);
3233 level
= btrfs_header_level(buf
);
3235 if (!test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) && level
== 0)
3239 process_func
= btrfs_inc_extent_ref
;
3241 process_func
= btrfs_free_extent
;
3244 parent
= buf
->start
;
3248 for (i
= 0; i
< nritems
; i
++) {
3250 btrfs_item_key_to_cpu(buf
, &key
, i
);
3251 if (key
.type
!= BTRFS_EXTENT_DATA_KEY
)
3253 fi
= btrfs_item_ptr(buf
, i
,
3254 struct btrfs_file_extent_item
);
3255 if (btrfs_file_extent_type(buf
, fi
) ==
3256 BTRFS_FILE_EXTENT_INLINE
)
3258 bytenr
= btrfs_file_extent_disk_bytenr(buf
, fi
);
3262 num_bytes
= btrfs_file_extent_disk_num_bytes(buf
, fi
);
3263 key
.offset
-= btrfs_file_extent_offset(buf
, fi
);
3264 ret
= process_func(trans
, root
, bytenr
, num_bytes
,
3265 parent
, ref_root
, key
.objectid
,
3270 bytenr
= btrfs_node_blockptr(buf
, i
);
3271 num_bytes
= fs_info
->nodesize
;
3272 ret
= process_func(trans
, root
, bytenr
, num_bytes
,
3273 parent
, ref_root
, level
- 1, 0);
3283 int btrfs_inc_ref(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
3284 struct extent_buffer
*buf
, int full_backref
)
3286 return __btrfs_mod_ref(trans
, root
, buf
, full_backref
, 1);
3289 int btrfs_dec_ref(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
3290 struct extent_buffer
*buf
, int full_backref
)
3292 return __btrfs_mod_ref(trans
, root
, buf
, full_backref
, 0);
3295 static int write_one_cache_group(struct btrfs_trans_handle
*trans
,
3296 struct btrfs_fs_info
*fs_info
,
3297 struct btrfs_path
*path
,
3298 struct btrfs_block_group_cache
*cache
)
3301 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
3303 struct extent_buffer
*leaf
;
3305 ret
= btrfs_search_slot(trans
, extent_root
, &cache
->key
, path
, 0, 1);
3312 leaf
= path
->nodes
[0];
3313 bi
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
3314 write_extent_buffer(leaf
, &cache
->item
, bi
, sizeof(cache
->item
));
3315 btrfs_mark_buffer_dirty(leaf
);
3317 btrfs_release_path(path
);
3322 static struct btrfs_block_group_cache
*
3323 next_block_group(struct btrfs_fs_info
*fs_info
,
3324 struct btrfs_block_group_cache
*cache
)
3326 struct rb_node
*node
;
3328 spin_lock(&fs_info
->block_group_cache_lock
);
3330 /* If our block group was removed, we need a full search. */
3331 if (RB_EMPTY_NODE(&cache
->cache_node
)) {
3332 const u64 next_bytenr
= cache
->key
.objectid
+ cache
->key
.offset
;
3334 spin_unlock(&fs_info
->block_group_cache_lock
);
3335 btrfs_put_block_group(cache
);
3336 cache
= btrfs_lookup_first_block_group(fs_info
, next_bytenr
); return cache
;
3338 node
= rb_next(&cache
->cache_node
);
3339 btrfs_put_block_group(cache
);
3341 cache
= rb_entry(node
, struct btrfs_block_group_cache
,
3343 btrfs_get_block_group(cache
);
3346 spin_unlock(&fs_info
->block_group_cache_lock
);
3350 static int cache_save_setup(struct btrfs_block_group_cache
*block_group
,
3351 struct btrfs_trans_handle
*trans
,
3352 struct btrfs_path
*path
)
3354 struct btrfs_fs_info
*fs_info
= block_group
->fs_info
;
3355 struct btrfs_root
*root
= fs_info
->tree_root
;
3356 struct inode
*inode
= NULL
;
3357 struct extent_changeset
*data_reserved
= NULL
;
3359 int dcs
= BTRFS_DC_ERROR
;
3365 * If this block group is smaller than 100 megs don't bother caching the
3368 if (block_group
->key
.offset
< (100 * SZ_1M
)) {
3369 spin_lock(&block_group
->lock
);
3370 block_group
->disk_cache_state
= BTRFS_DC_WRITTEN
;
3371 spin_unlock(&block_group
->lock
);
3378 inode
= lookup_free_space_inode(fs_info
, block_group
, path
);
3379 if (IS_ERR(inode
) && PTR_ERR(inode
) != -ENOENT
) {
3380 ret
= PTR_ERR(inode
);
3381 btrfs_release_path(path
);
3385 if (IS_ERR(inode
)) {
3389 if (block_group
->ro
)
3392 ret
= create_free_space_inode(fs_info
, trans
, block_group
,
3400 * We want to set the generation to 0, that way if anything goes wrong
3401 * from here on out we know not to trust this cache when we load up next
3404 BTRFS_I(inode
)->generation
= 0;
3405 ret
= btrfs_update_inode(trans
, root
, inode
);
3408 * So theoretically we could recover from this, simply set the
3409 * super cache generation to 0 so we know to invalidate the
3410 * cache, but then we'd have to keep track of the block groups
3411 * that fail this way so we know we _have_ to reset this cache
3412 * before the next commit or risk reading stale cache. So to
3413 * limit our exposure to horrible edge cases lets just abort the
3414 * transaction, this only happens in really bad situations
3417 btrfs_abort_transaction(trans
, ret
);
3422 /* We've already setup this transaction, go ahead and exit */
3423 if (block_group
->cache_generation
== trans
->transid
&&
3424 i_size_read(inode
)) {
3425 dcs
= BTRFS_DC_SETUP
;
3429 if (i_size_read(inode
) > 0) {
3430 ret
= btrfs_check_trunc_cache_free_space(fs_info
,
3431 &fs_info
->global_block_rsv
);
3435 ret
= btrfs_truncate_free_space_cache(trans
, NULL
, inode
);
3440 spin_lock(&block_group
->lock
);
3441 if (block_group
->cached
!= BTRFS_CACHE_FINISHED
||
3442 !btrfs_test_opt(fs_info
, SPACE_CACHE
)) {
3444 * don't bother trying to write stuff out _if_
3445 * a) we're not cached,
3446 * b) we're with nospace_cache mount option,
3447 * c) we're with v2 space_cache (FREE_SPACE_TREE).
3449 dcs
= BTRFS_DC_WRITTEN
;
3450 spin_unlock(&block_group
->lock
);
3453 spin_unlock(&block_group
->lock
);
3456 * We hit an ENOSPC when setting up the cache in this transaction, just
3457 * skip doing the setup, we've already cleared the cache so we're safe.
3459 if (test_bit(BTRFS_TRANS_CACHE_ENOSPC
, &trans
->transaction
->flags
)) {
3465 * Try to preallocate enough space based on how big the block group is.
3466 * Keep in mind this has to include any pinned space which could end up
3467 * taking up quite a bit since it's not folded into the other space
3470 num_pages
= div_u64(block_group
->key
.offset
, SZ_256M
);
3475 num_pages
*= PAGE_SIZE
;
3477 ret
= btrfs_check_data_free_space(inode
, &data_reserved
, 0, num_pages
);
3481 ret
= btrfs_prealloc_file_range_trans(inode
, trans
, 0, 0, num_pages
,
3482 num_pages
, num_pages
,
3485 * Our cache requires contiguous chunks so that we don't modify a bunch
3486 * of metadata or split extents when writing the cache out, which means
3487 * we can enospc if we are heavily fragmented in addition to just normal
3488 * out of space conditions. So if we hit this just skip setting up any
3489 * other block groups for this transaction, maybe we'll unpin enough
3490 * space the next time around.
3493 dcs
= BTRFS_DC_SETUP
;
3494 else if (ret
== -ENOSPC
)
3495 set_bit(BTRFS_TRANS_CACHE_ENOSPC
, &trans
->transaction
->flags
);
3500 btrfs_release_path(path
);
3502 spin_lock(&block_group
->lock
);
3503 if (!ret
&& dcs
== BTRFS_DC_SETUP
)
3504 block_group
->cache_generation
= trans
->transid
;
3505 block_group
->disk_cache_state
= dcs
;
3506 spin_unlock(&block_group
->lock
);
3508 extent_changeset_free(data_reserved
);
3512 int btrfs_setup_space_cache(struct btrfs_trans_handle
*trans
,
3513 struct btrfs_fs_info
*fs_info
)
3515 struct btrfs_block_group_cache
*cache
, *tmp
;
3516 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
3517 struct btrfs_path
*path
;
3519 if (list_empty(&cur_trans
->dirty_bgs
) ||
3520 !btrfs_test_opt(fs_info
, SPACE_CACHE
))
3523 path
= btrfs_alloc_path();
3527 /* Could add new block groups, use _safe just in case */
3528 list_for_each_entry_safe(cache
, tmp
, &cur_trans
->dirty_bgs
,
3530 if (cache
->disk_cache_state
== BTRFS_DC_CLEAR
)
3531 cache_save_setup(cache
, trans
, path
);
3534 btrfs_free_path(path
);
3539 * transaction commit does final block group cache writeback during a
3540 * critical section where nothing is allowed to change the FS. This is
3541 * required in order for the cache to actually match the block group,
3542 * but can introduce a lot of latency into the commit.
3544 * So, btrfs_start_dirty_block_groups is here to kick off block group
3545 * cache IO. There's a chance we'll have to redo some of it if the
3546 * block group changes again during the commit, but it greatly reduces
3547 * the commit latency by getting rid of the easy block groups while
3548 * we're still allowing others to join the commit.
3550 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle
*trans
)
3552 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
3553 struct btrfs_block_group_cache
*cache
;
3554 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
3557 struct btrfs_path
*path
= NULL
;
3559 struct list_head
*io
= &cur_trans
->io_bgs
;
3560 int num_started
= 0;
3563 spin_lock(&cur_trans
->dirty_bgs_lock
);
3564 if (list_empty(&cur_trans
->dirty_bgs
)) {
3565 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3568 list_splice_init(&cur_trans
->dirty_bgs
, &dirty
);
3569 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3573 * make sure all the block groups on our dirty list actually
3576 btrfs_create_pending_block_groups(trans
);
3579 path
= btrfs_alloc_path();
3585 * cache_write_mutex is here only to save us from balance or automatic
3586 * removal of empty block groups deleting this block group while we are
3587 * writing out the cache
3589 mutex_lock(&trans
->transaction
->cache_write_mutex
);
3590 while (!list_empty(&dirty
)) {
3591 cache
= list_first_entry(&dirty
,
3592 struct btrfs_block_group_cache
,
3595 * this can happen if something re-dirties a block
3596 * group that is already under IO. Just wait for it to
3597 * finish and then do it all again
3599 if (!list_empty(&cache
->io_list
)) {
3600 list_del_init(&cache
->io_list
);
3601 btrfs_wait_cache_io(trans
, cache
, path
);
3602 btrfs_put_block_group(cache
);
3607 * btrfs_wait_cache_io uses the cache->dirty_list to decide
3608 * if it should update the cache_state. Don't delete
3609 * until after we wait.
3611 * Since we're not running in the commit critical section
3612 * we need the dirty_bgs_lock to protect from update_block_group
3614 spin_lock(&cur_trans
->dirty_bgs_lock
);
3615 list_del_init(&cache
->dirty_list
);
3616 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3620 cache_save_setup(cache
, trans
, path
);
3622 if (cache
->disk_cache_state
== BTRFS_DC_SETUP
) {
3623 cache
->io_ctl
.inode
= NULL
;
3624 ret
= btrfs_write_out_cache(fs_info
, trans
,
3626 if (ret
== 0 && cache
->io_ctl
.inode
) {
3631 * The cache_write_mutex is protecting the
3632 * io_list, also refer to the definition of
3633 * btrfs_transaction::io_bgs for more details
3635 list_add_tail(&cache
->io_list
, io
);
3638 * if we failed to write the cache, the
3639 * generation will be bad and life goes on
3645 ret
= write_one_cache_group(trans
, fs_info
,
3648 * Our block group might still be attached to the list
3649 * of new block groups in the transaction handle of some
3650 * other task (struct btrfs_trans_handle->new_bgs). This
3651 * means its block group item isn't yet in the extent
3652 * tree. If this happens ignore the error, as we will
3653 * try again later in the critical section of the
3654 * transaction commit.
3656 if (ret
== -ENOENT
) {
3658 spin_lock(&cur_trans
->dirty_bgs_lock
);
3659 if (list_empty(&cache
->dirty_list
)) {
3660 list_add_tail(&cache
->dirty_list
,
3661 &cur_trans
->dirty_bgs
);
3662 btrfs_get_block_group(cache
);
3664 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3666 btrfs_abort_transaction(trans
, ret
);
3670 /* if its not on the io list, we need to put the block group */
3672 btrfs_put_block_group(cache
);
3678 * Avoid blocking other tasks for too long. It might even save
3679 * us from writing caches for block groups that are going to be
3682 mutex_unlock(&trans
->transaction
->cache_write_mutex
);
3683 mutex_lock(&trans
->transaction
->cache_write_mutex
);
3685 mutex_unlock(&trans
->transaction
->cache_write_mutex
);
3688 * go through delayed refs for all the stuff we've just kicked off
3689 * and then loop back (just once)
3691 ret
= btrfs_run_delayed_refs(trans
, 0);
3692 if (!ret
&& loops
== 0) {
3694 spin_lock(&cur_trans
->dirty_bgs_lock
);
3695 list_splice_init(&cur_trans
->dirty_bgs
, &dirty
);
3697 * dirty_bgs_lock protects us from concurrent block group
3698 * deletes too (not just cache_write_mutex).
3700 if (!list_empty(&dirty
)) {
3701 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3704 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3705 } else if (ret
< 0) {
3706 btrfs_cleanup_dirty_bgs(cur_trans
, fs_info
);
3709 btrfs_free_path(path
);
3713 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle
*trans
,
3714 struct btrfs_fs_info
*fs_info
)
3716 struct btrfs_block_group_cache
*cache
;
3717 struct btrfs_transaction
*cur_trans
= trans
->transaction
;
3720 struct btrfs_path
*path
;
3721 struct list_head
*io
= &cur_trans
->io_bgs
;
3722 int num_started
= 0;
3724 path
= btrfs_alloc_path();
3729 * Even though we are in the critical section of the transaction commit,
3730 * we can still have concurrent tasks adding elements to this
3731 * transaction's list of dirty block groups. These tasks correspond to
3732 * endio free space workers started when writeback finishes for a
3733 * space cache, which run inode.c:btrfs_finish_ordered_io(), and can
3734 * allocate new block groups as a result of COWing nodes of the root
3735 * tree when updating the free space inode. The writeback for the space
3736 * caches is triggered by an earlier call to
3737 * btrfs_start_dirty_block_groups() and iterations of the following
3739 * Also we want to do the cache_save_setup first and then run the
3740 * delayed refs to make sure we have the best chance at doing this all
3743 spin_lock(&cur_trans
->dirty_bgs_lock
);
3744 while (!list_empty(&cur_trans
->dirty_bgs
)) {
3745 cache
= list_first_entry(&cur_trans
->dirty_bgs
,
3746 struct btrfs_block_group_cache
,
3750 * this can happen if cache_save_setup re-dirties a block
3751 * group that is already under IO. Just wait for it to
3752 * finish and then do it all again
3754 if (!list_empty(&cache
->io_list
)) {
3755 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3756 list_del_init(&cache
->io_list
);
3757 btrfs_wait_cache_io(trans
, cache
, path
);
3758 btrfs_put_block_group(cache
);
3759 spin_lock(&cur_trans
->dirty_bgs_lock
);
3763 * don't remove from the dirty list until after we've waited
3766 list_del_init(&cache
->dirty_list
);
3767 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3770 cache_save_setup(cache
, trans
, path
);
3773 ret
= btrfs_run_delayed_refs(trans
,
3774 (unsigned long) -1);
3776 if (!ret
&& cache
->disk_cache_state
== BTRFS_DC_SETUP
) {
3777 cache
->io_ctl
.inode
= NULL
;
3778 ret
= btrfs_write_out_cache(fs_info
, trans
,
3780 if (ret
== 0 && cache
->io_ctl
.inode
) {
3783 list_add_tail(&cache
->io_list
, io
);
3786 * if we failed to write the cache, the
3787 * generation will be bad and life goes on
3793 ret
= write_one_cache_group(trans
, fs_info
,
3796 * One of the free space endio workers might have
3797 * created a new block group while updating a free space
3798 * cache's inode (at inode.c:btrfs_finish_ordered_io())
3799 * and hasn't released its transaction handle yet, in
3800 * which case the new block group is still attached to
3801 * its transaction handle and its creation has not
3802 * finished yet (no block group item in the extent tree
3803 * yet, etc). If this is the case, wait for all free
3804 * space endio workers to finish and retry. This is a
3805 * a very rare case so no need for a more efficient and
3808 if (ret
== -ENOENT
) {
3809 wait_event(cur_trans
->writer_wait
,
3810 atomic_read(&cur_trans
->num_writers
) == 1);
3811 ret
= write_one_cache_group(trans
, fs_info
,
3815 btrfs_abort_transaction(trans
, ret
);
3818 /* if its not on the io list, we need to put the block group */
3820 btrfs_put_block_group(cache
);
3821 spin_lock(&cur_trans
->dirty_bgs_lock
);
3823 spin_unlock(&cur_trans
->dirty_bgs_lock
);
3826 * Refer to the definition of io_bgs member for details why it's safe
3827 * to use it without any locking
3829 while (!list_empty(io
)) {
3830 cache
= list_first_entry(io
, struct btrfs_block_group_cache
,
3832 list_del_init(&cache
->io_list
);
3833 btrfs_wait_cache_io(trans
, cache
, path
);
3834 btrfs_put_block_group(cache
);
3837 btrfs_free_path(path
);
3841 int btrfs_extent_readonly(struct btrfs_fs_info
*fs_info
, u64 bytenr
)
3843 struct btrfs_block_group_cache
*block_group
;
3846 block_group
= btrfs_lookup_block_group(fs_info
, bytenr
);
3847 if (!block_group
|| block_group
->ro
)
3850 btrfs_put_block_group(block_group
);
3854 bool btrfs_inc_nocow_writers(struct btrfs_fs_info
*fs_info
, u64 bytenr
)
3856 struct btrfs_block_group_cache
*bg
;
3859 bg
= btrfs_lookup_block_group(fs_info
, bytenr
);
3863 spin_lock(&bg
->lock
);
3867 atomic_inc(&bg
->nocow_writers
);
3868 spin_unlock(&bg
->lock
);
3870 /* no put on block group, done by btrfs_dec_nocow_writers */
3872 btrfs_put_block_group(bg
);
3878 void btrfs_dec_nocow_writers(struct btrfs_fs_info
*fs_info
, u64 bytenr
)
3880 struct btrfs_block_group_cache
*bg
;
3882 bg
= btrfs_lookup_block_group(fs_info
, bytenr
);
3884 if (atomic_dec_and_test(&bg
->nocow_writers
))
3885 wake_up_var(&bg
->nocow_writers
);
3887 * Once for our lookup and once for the lookup done by a previous call
3888 * to btrfs_inc_nocow_writers()
3890 btrfs_put_block_group(bg
);
3891 btrfs_put_block_group(bg
);
3894 void btrfs_wait_nocow_writers(struct btrfs_block_group_cache
*bg
)
3896 wait_var_event(&bg
->nocow_writers
, !atomic_read(&bg
->nocow_writers
));
3899 static const char *alloc_name(u64 flags
)
3902 case BTRFS_BLOCK_GROUP_METADATA
|BTRFS_BLOCK_GROUP_DATA
:
3904 case BTRFS_BLOCK_GROUP_METADATA
:
3906 case BTRFS_BLOCK_GROUP_DATA
:
3908 case BTRFS_BLOCK_GROUP_SYSTEM
:
3912 return "invalid-combination";
3916 static int create_space_info(struct btrfs_fs_info
*info
, u64 flags
)
3919 struct btrfs_space_info
*space_info
;
3923 space_info
= kzalloc(sizeof(*space_info
), GFP_NOFS
);
3927 ret
= percpu_counter_init(&space_info
->total_bytes_pinned
, 0,
3934 for (i
= 0; i
< BTRFS_NR_RAID_TYPES
; i
++)
3935 INIT_LIST_HEAD(&space_info
->block_groups
[i
]);
3936 init_rwsem(&space_info
->groups_sem
);
3937 spin_lock_init(&space_info
->lock
);
3938 space_info
->flags
= flags
& BTRFS_BLOCK_GROUP_TYPE_MASK
;
3939 space_info
->force_alloc
= CHUNK_ALLOC_NO_FORCE
;
3940 init_waitqueue_head(&space_info
->wait
);
3941 INIT_LIST_HEAD(&space_info
->ro_bgs
);
3942 INIT_LIST_HEAD(&space_info
->tickets
);
3943 INIT_LIST_HEAD(&space_info
->priority_tickets
);
3945 ret
= kobject_init_and_add(&space_info
->kobj
, &space_info_ktype
,
3946 info
->space_info_kobj
, "%s",
3947 alloc_name(space_info
->flags
));
3949 percpu_counter_destroy(&space_info
->total_bytes_pinned
);
3954 list_add_rcu(&space_info
->list
, &info
->space_info
);
3955 if (flags
& BTRFS_BLOCK_GROUP_DATA
)
3956 info
->data_sinfo
= space_info
;
3961 static void update_space_info(struct btrfs_fs_info
*info
, u64 flags
,
3962 u64 total_bytes
, u64 bytes_used
,
3964 struct btrfs_space_info
**space_info
)
3966 struct btrfs_space_info
*found
;
3969 factor
= btrfs_bg_type_to_factor(flags
);
3971 found
= __find_space_info(info
, flags
);
3973 spin_lock(&found
->lock
);
3974 found
->total_bytes
+= total_bytes
;
3975 found
->disk_total
+= total_bytes
* factor
;
3976 found
->bytes_used
+= bytes_used
;
3977 found
->disk_used
+= bytes_used
* factor
;
3978 found
->bytes_readonly
+= bytes_readonly
;
3979 if (total_bytes
> 0)
3981 space_info_add_new_bytes(info
, found
, total_bytes
-
3982 bytes_used
- bytes_readonly
);
3983 spin_unlock(&found
->lock
);
3984 *space_info
= found
;
3987 static void set_avail_alloc_bits(struct btrfs_fs_info
*fs_info
, u64 flags
)
3989 u64 extra_flags
= chunk_to_extended(flags
) &
3990 BTRFS_EXTENDED_PROFILE_MASK
;
3992 write_seqlock(&fs_info
->profiles_lock
);
3993 if (flags
& BTRFS_BLOCK_GROUP_DATA
)
3994 fs_info
->avail_data_alloc_bits
|= extra_flags
;
3995 if (flags
& BTRFS_BLOCK_GROUP_METADATA
)
3996 fs_info
->avail_metadata_alloc_bits
|= extra_flags
;
3997 if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
)
3998 fs_info
->avail_system_alloc_bits
|= extra_flags
;
3999 write_sequnlock(&fs_info
->profiles_lock
);
4003 * returns target flags in extended format or 0 if restripe for this
4004 * chunk_type is not in progress
4006 * should be called with balance_lock held
4008 static u64
get_restripe_target(struct btrfs_fs_info
*fs_info
, u64 flags
)
4010 struct btrfs_balance_control
*bctl
= fs_info
->balance_ctl
;
4016 if (flags
& BTRFS_BLOCK_GROUP_DATA
&&
4017 bctl
->data
.flags
& BTRFS_BALANCE_ARGS_CONVERT
) {
4018 target
= BTRFS_BLOCK_GROUP_DATA
| bctl
->data
.target
;
4019 } else if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
&&
4020 bctl
->sys
.flags
& BTRFS_BALANCE_ARGS_CONVERT
) {
4021 target
= BTRFS_BLOCK_GROUP_SYSTEM
| bctl
->sys
.target
;
4022 } else if (flags
& BTRFS_BLOCK_GROUP_METADATA
&&
4023 bctl
->meta
.flags
& BTRFS_BALANCE_ARGS_CONVERT
) {
4024 target
= BTRFS_BLOCK_GROUP_METADATA
| bctl
->meta
.target
;
4031 * @flags: available profiles in extended format (see ctree.h)
4033 * Returns reduced profile in chunk format. If profile changing is in
4034 * progress (either running or paused) picks the target profile (if it's
4035 * already available), otherwise falls back to plain reducing.
4037 static u64
btrfs_reduce_alloc_profile(struct btrfs_fs_info
*fs_info
, u64 flags
)
4039 u64 num_devices
= fs_info
->fs_devices
->rw_devices
;
4045 * see if restripe for this chunk_type is in progress, if so
4046 * try to reduce to the target profile
4048 spin_lock(&fs_info
->balance_lock
);
4049 target
= get_restripe_target(fs_info
, flags
);
4051 /* pick target profile only if it's already available */
4052 if ((flags
& target
) & BTRFS_EXTENDED_PROFILE_MASK
) {
4053 spin_unlock(&fs_info
->balance_lock
);
4054 return extended_to_chunk(target
);
4057 spin_unlock(&fs_info
->balance_lock
);
4059 /* First, mask out the RAID levels which aren't possible */
4060 for (raid_type
= 0; raid_type
< BTRFS_NR_RAID_TYPES
; raid_type
++) {
4061 if (num_devices
>= btrfs_raid_array
[raid_type
].devs_min
)
4062 allowed
|= btrfs_raid_array
[raid_type
].bg_flag
;
4066 if (allowed
& BTRFS_BLOCK_GROUP_RAID6
)
4067 allowed
= BTRFS_BLOCK_GROUP_RAID6
;
4068 else if (allowed
& BTRFS_BLOCK_GROUP_RAID5
)
4069 allowed
= BTRFS_BLOCK_GROUP_RAID5
;
4070 else if (allowed
& BTRFS_BLOCK_GROUP_RAID10
)
4071 allowed
= BTRFS_BLOCK_GROUP_RAID10
;
4072 else if (allowed
& BTRFS_BLOCK_GROUP_RAID1
)
4073 allowed
= BTRFS_BLOCK_GROUP_RAID1
;
4074 else if (allowed
& BTRFS_BLOCK_GROUP_RAID0
)
4075 allowed
= BTRFS_BLOCK_GROUP_RAID0
;
4077 flags
&= ~BTRFS_BLOCK_GROUP_PROFILE_MASK
;
4079 return extended_to_chunk(flags
| allowed
);
4082 static u64
get_alloc_profile(struct btrfs_fs_info
*fs_info
, u64 orig_flags
)
4089 seq
= read_seqbegin(&fs_info
->profiles_lock
);
4091 if (flags
& BTRFS_BLOCK_GROUP_DATA
)
4092 flags
|= fs_info
->avail_data_alloc_bits
;
4093 else if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
)
4094 flags
|= fs_info
->avail_system_alloc_bits
;
4095 else if (flags
& BTRFS_BLOCK_GROUP_METADATA
)
4096 flags
|= fs_info
->avail_metadata_alloc_bits
;
4097 } while (read_seqretry(&fs_info
->profiles_lock
, seq
));
4099 return btrfs_reduce_alloc_profile(fs_info
, flags
);
4102 static u64
get_alloc_profile_by_root(struct btrfs_root
*root
, int data
)
4104 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
4109 flags
= BTRFS_BLOCK_GROUP_DATA
;
4110 else if (root
== fs_info
->chunk_root
)
4111 flags
= BTRFS_BLOCK_GROUP_SYSTEM
;
4113 flags
= BTRFS_BLOCK_GROUP_METADATA
;
4115 ret
= get_alloc_profile(fs_info
, flags
);
4119 u64
btrfs_data_alloc_profile(struct btrfs_fs_info
*fs_info
)
4121 return get_alloc_profile(fs_info
, BTRFS_BLOCK_GROUP_DATA
);
4124 u64
btrfs_metadata_alloc_profile(struct btrfs_fs_info
*fs_info
)
4126 return get_alloc_profile(fs_info
, BTRFS_BLOCK_GROUP_METADATA
);
4129 u64
btrfs_system_alloc_profile(struct btrfs_fs_info
*fs_info
)
4131 return get_alloc_profile(fs_info
, BTRFS_BLOCK_GROUP_SYSTEM
);
4134 static u64
btrfs_space_info_used(struct btrfs_space_info
*s_info
,
4135 bool may_use_included
)
4138 return s_info
->bytes_used
+ s_info
->bytes_reserved
+
4139 s_info
->bytes_pinned
+ s_info
->bytes_readonly
+
4140 (may_use_included
? s_info
->bytes_may_use
: 0);
4143 int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode
*inode
, u64 bytes
)
4145 struct btrfs_root
*root
= inode
->root
;
4146 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
4147 struct btrfs_space_info
*data_sinfo
= fs_info
->data_sinfo
;
4150 int need_commit
= 2;
4151 int have_pinned_space
;
4153 /* make sure bytes are sectorsize aligned */
4154 bytes
= ALIGN(bytes
, fs_info
->sectorsize
);
4156 if (btrfs_is_free_space_inode(inode
)) {
4158 ASSERT(current
->journal_info
);
4162 /* make sure we have enough space to handle the data first */
4163 spin_lock(&data_sinfo
->lock
);
4164 used
= btrfs_space_info_used(data_sinfo
, true);
4166 if (used
+ bytes
> data_sinfo
->total_bytes
) {
4167 struct btrfs_trans_handle
*trans
;
4170 * if we don't have enough free bytes in this space then we need
4171 * to alloc a new chunk.
4173 if (!data_sinfo
->full
) {
4176 data_sinfo
->force_alloc
= CHUNK_ALLOC_FORCE
;
4177 spin_unlock(&data_sinfo
->lock
);
4179 alloc_target
= btrfs_data_alloc_profile(fs_info
);
4181 * It is ugly that we don't call nolock join
4182 * transaction for the free space inode case here.
4183 * But it is safe because we only do the data space
4184 * reservation for the free space cache in the
4185 * transaction context, the common join transaction
4186 * just increase the counter of the current transaction
4187 * handler, doesn't try to acquire the trans_lock of
4190 trans
= btrfs_join_transaction(root
);
4192 return PTR_ERR(trans
);
4194 ret
= do_chunk_alloc(trans
, alloc_target
,
4195 CHUNK_ALLOC_NO_FORCE
);
4196 btrfs_end_transaction(trans
);
4201 have_pinned_space
= 1;
4210 * If we don't have enough pinned space to deal with this
4211 * allocation, and no removed chunk in current transaction,
4212 * don't bother committing the transaction.
4214 have_pinned_space
= __percpu_counter_compare(
4215 &data_sinfo
->total_bytes_pinned
,
4216 used
+ bytes
- data_sinfo
->total_bytes
,
4217 BTRFS_TOTAL_BYTES_PINNED_BATCH
);
4218 spin_unlock(&data_sinfo
->lock
);
4220 /* commit the current transaction and try again */
4225 if (need_commit
> 0) {
4226 btrfs_start_delalloc_roots(fs_info
, -1);
4227 btrfs_wait_ordered_roots(fs_info
, U64_MAX
, 0,
4231 trans
= btrfs_join_transaction(root
);
4233 return PTR_ERR(trans
);
4234 if (have_pinned_space
>= 0 ||
4235 test_bit(BTRFS_TRANS_HAVE_FREE_BGS
,
4236 &trans
->transaction
->flags
) ||
4238 ret
= btrfs_commit_transaction(trans
);
4242 * The cleaner kthread might still be doing iput
4243 * operations. Wait for it to finish so that
4244 * more space is released.
4246 mutex_lock(&fs_info
->cleaner_delayed_iput_mutex
);
4247 mutex_unlock(&fs_info
->cleaner_delayed_iput_mutex
);
4250 btrfs_end_transaction(trans
);
4254 trace_btrfs_space_reservation(fs_info
,
4255 "space_info:enospc",
4256 data_sinfo
->flags
, bytes
, 1);
4259 data_sinfo
->bytes_may_use
+= bytes
;
4260 trace_btrfs_space_reservation(fs_info
, "space_info",
4261 data_sinfo
->flags
, bytes
, 1);
4262 spin_unlock(&data_sinfo
->lock
);
4267 int btrfs_check_data_free_space(struct inode
*inode
,
4268 struct extent_changeset
**reserved
, u64 start
, u64 len
)
4270 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
4273 /* align the range */
4274 len
= round_up(start
+ len
, fs_info
->sectorsize
) -
4275 round_down(start
, fs_info
->sectorsize
);
4276 start
= round_down(start
, fs_info
->sectorsize
);
4278 ret
= btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode
), len
);
4282 /* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
4283 ret
= btrfs_qgroup_reserve_data(inode
, reserved
, start
, len
);
4285 btrfs_free_reserved_data_space_noquota(inode
, start
, len
);
4292 * Called if we need to clear a data reservation for this inode
4293 * Normally in a error case.
4295 * This one will *NOT* use accurate qgroup reserved space API, just for case
4296 * which we can't sleep and is sure it won't affect qgroup reserved space.
4297 * Like clear_bit_hook().
4299 void btrfs_free_reserved_data_space_noquota(struct inode
*inode
, u64 start
,
4302 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
4303 struct btrfs_space_info
*data_sinfo
;
4305 /* Make sure the range is aligned to sectorsize */
4306 len
= round_up(start
+ len
, fs_info
->sectorsize
) -
4307 round_down(start
, fs_info
->sectorsize
);
4308 start
= round_down(start
, fs_info
->sectorsize
);
4310 data_sinfo
= fs_info
->data_sinfo
;
4311 spin_lock(&data_sinfo
->lock
);
4312 if (WARN_ON(data_sinfo
->bytes_may_use
< len
))
4313 data_sinfo
->bytes_may_use
= 0;
4315 data_sinfo
->bytes_may_use
-= len
;
4316 trace_btrfs_space_reservation(fs_info
, "space_info",
4317 data_sinfo
->flags
, len
, 0);
4318 spin_unlock(&data_sinfo
->lock
);
4322 * Called if we need to clear a data reservation for this inode
4323 * Normally in a error case.
4325 * This one will handle the per-inode data rsv map for accurate reserved
4328 void btrfs_free_reserved_data_space(struct inode
*inode
,
4329 struct extent_changeset
*reserved
, u64 start
, u64 len
)
4331 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
4333 /* Make sure the range is aligned to sectorsize */
4334 len
= round_up(start
+ len
, root
->fs_info
->sectorsize
) -
4335 round_down(start
, root
->fs_info
->sectorsize
);
4336 start
= round_down(start
, root
->fs_info
->sectorsize
);
4338 btrfs_free_reserved_data_space_noquota(inode
, start
, len
);
4339 btrfs_qgroup_free_data(inode
, reserved
, start
, len
);
4342 static void force_metadata_allocation(struct btrfs_fs_info
*info
)
4344 struct list_head
*head
= &info
->space_info
;
4345 struct btrfs_space_info
*found
;
4348 list_for_each_entry_rcu(found
, head
, list
) {
4349 if (found
->flags
& BTRFS_BLOCK_GROUP_METADATA
)
4350 found
->force_alloc
= CHUNK_ALLOC_FORCE
;
4355 static inline u64
calc_global_rsv_need_space(struct btrfs_block_rsv
*global
)
4357 return (global
->size
<< 1);
4360 static int should_alloc_chunk(struct btrfs_fs_info
*fs_info
,
4361 struct btrfs_space_info
*sinfo
, int force
)
4363 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
4364 u64 bytes_used
= btrfs_space_info_used(sinfo
, false);
4367 if (force
== CHUNK_ALLOC_FORCE
)
4371 * We need to take into account the global rsv because for all intents
4372 * and purposes it's used space. Don't worry about locking the
4373 * global_rsv, it doesn't change except when the transaction commits.
4375 if (sinfo
->flags
& BTRFS_BLOCK_GROUP_METADATA
)
4376 bytes_used
+= calc_global_rsv_need_space(global_rsv
);
4379 * in limited mode, we want to have some free space up to
4380 * about 1% of the FS size.
4382 if (force
== CHUNK_ALLOC_LIMITED
) {
4383 thresh
= btrfs_super_total_bytes(fs_info
->super_copy
);
4384 thresh
= max_t(u64
, SZ_64M
, div_factor_fine(thresh
, 1));
4386 if (sinfo
->total_bytes
- bytes_used
< thresh
)
4390 if (bytes_used
+ SZ_2M
< div_factor(sinfo
->total_bytes
, 8))
4395 static u64
get_profile_num_devs(struct btrfs_fs_info
*fs_info
, u64 type
)
4399 if (type
& (BTRFS_BLOCK_GROUP_RAID10
|
4400 BTRFS_BLOCK_GROUP_RAID0
|
4401 BTRFS_BLOCK_GROUP_RAID5
|
4402 BTRFS_BLOCK_GROUP_RAID6
))
4403 num_dev
= fs_info
->fs_devices
->rw_devices
;
4404 else if (type
& BTRFS_BLOCK_GROUP_RAID1
)
4407 num_dev
= 1; /* DUP or single */
4413 * If @is_allocation is true, reserve space in the system space info necessary
4414 * for allocating a chunk, otherwise if it's false, reserve space necessary for
4417 void check_system_chunk(struct btrfs_trans_handle
*trans
, u64 type
)
4419 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
4420 struct btrfs_space_info
*info
;
4427 * Needed because we can end up allocating a system chunk and for an
4428 * atomic and race free space reservation in the chunk block reserve.
4430 lockdep_assert_held(&fs_info
->chunk_mutex
);
4432 info
= __find_space_info(fs_info
, BTRFS_BLOCK_GROUP_SYSTEM
);
4433 spin_lock(&info
->lock
);
4434 left
= info
->total_bytes
- btrfs_space_info_used(info
, true);
4435 spin_unlock(&info
->lock
);
4437 num_devs
= get_profile_num_devs(fs_info
, type
);
4439 /* num_devs device items to update and 1 chunk item to add or remove */
4440 thresh
= btrfs_calc_trunc_metadata_size(fs_info
, num_devs
) +
4441 btrfs_calc_trans_metadata_size(fs_info
, 1);
4443 if (left
< thresh
&& btrfs_test_opt(fs_info
, ENOSPC_DEBUG
)) {
4444 btrfs_info(fs_info
, "left=%llu, need=%llu, flags=%llu",
4445 left
, thresh
, type
);
4446 dump_space_info(fs_info
, info
, 0, 0);
4449 if (left
< thresh
) {
4450 u64 flags
= btrfs_system_alloc_profile(fs_info
);
4453 * Ignore failure to create system chunk. We might end up not
4454 * needing it, as we might not need to COW all nodes/leafs from
4455 * the paths we visit in the chunk tree (they were already COWed
4456 * or created in the current transaction for example).
4458 ret
= btrfs_alloc_chunk(trans
, flags
);
4462 ret
= btrfs_block_rsv_add(fs_info
->chunk_root
,
4463 &fs_info
->chunk_block_rsv
,
4464 thresh
, BTRFS_RESERVE_NO_FLUSH
);
4466 trans
->chunk_bytes_reserved
+= thresh
;
4471 * If force is CHUNK_ALLOC_FORCE:
4472 * - return 1 if it successfully allocates a chunk,
4473 * - return errors including -ENOSPC otherwise.
4474 * If force is NOT CHUNK_ALLOC_FORCE:
4475 * - return 0 if it doesn't need to allocate a new chunk,
4476 * - return 1 if it successfully allocates a chunk,
4477 * - return errors including -ENOSPC otherwise.
4479 static int do_chunk_alloc(struct btrfs_trans_handle
*trans
, u64 flags
,
4482 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
4483 struct btrfs_space_info
*space_info
;
4484 bool wait_for_alloc
= false;
4485 bool should_alloc
= false;
4488 /* Don't re-enter if we're already allocating a chunk */
4489 if (trans
->allocating_chunk
)
4492 space_info
= __find_space_info(fs_info
, flags
);
4496 spin_lock(&space_info
->lock
);
4497 if (force
< space_info
->force_alloc
)
4498 force
= space_info
->force_alloc
;
4499 should_alloc
= should_alloc_chunk(fs_info
, space_info
, force
);
4500 if (space_info
->full
) {
4501 /* No more free physical space */
4506 spin_unlock(&space_info
->lock
);
4508 } else if (!should_alloc
) {
4509 spin_unlock(&space_info
->lock
);
4511 } else if (space_info
->chunk_alloc
) {
4513 * Someone is already allocating, so we need to block
4514 * until this someone is finished and then loop to
4515 * recheck if we should continue with our allocation
4518 wait_for_alloc
= true;
4519 spin_unlock(&space_info
->lock
);
4520 mutex_lock(&fs_info
->chunk_mutex
);
4521 mutex_unlock(&fs_info
->chunk_mutex
);
4523 /* Proceed with allocation */
4524 space_info
->chunk_alloc
= 1;
4525 wait_for_alloc
= false;
4526 spin_unlock(&space_info
->lock
);
4530 } while (wait_for_alloc
);
4532 mutex_lock(&fs_info
->chunk_mutex
);
4533 trans
->allocating_chunk
= true;
4536 * If we have mixed data/metadata chunks we want to make sure we keep
4537 * allocating mixed chunks instead of individual chunks.
4539 if (btrfs_mixed_space_info(space_info
))
4540 flags
|= (BTRFS_BLOCK_GROUP_DATA
| BTRFS_BLOCK_GROUP_METADATA
);
4543 * if we're doing a data chunk, go ahead and make sure that
4544 * we keep a reasonable number of metadata chunks allocated in the
4547 if (flags
& BTRFS_BLOCK_GROUP_DATA
&& fs_info
->metadata_ratio
) {
4548 fs_info
->data_chunk_allocations
++;
4549 if (!(fs_info
->data_chunk_allocations
%
4550 fs_info
->metadata_ratio
))
4551 force_metadata_allocation(fs_info
);
4555 * Check if we have enough space in SYSTEM chunk because we may need
4556 * to update devices.
4558 check_system_chunk(trans
, flags
);
4560 ret
= btrfs_alloc_chunk(trans
, flags
);
4561 trans
->allocating_chunk
= false;
4563 spin_lock(&space_info
->lock
);
4566 space_info
->full
= 1;
4573 space_info
->force_alloc
= CHUNK_ALLOC_NO_FORCE
;
4575 space_info
->chunk_alloc
= 0;
4576 spin_unlock(&space_info
->lock
);
4577 mutex_unlock(&fs_info
->chunk_mutex
);
4579 * When we allocate a new chunk we reserve space in the chunk block
4580 * reserve to make sure we can COW nodes/leafs in the chunk tree or
4581 * add new nodes/leafs to it if we end up needing to do it when
4582 * inserting the chunk item and updating device items as part of the
4583 * second phase of chunk allocation, performed by
4584 * btrfs_finish_chunk_alloc(). So make sure we don't accumulate a
4585 * large number of new block groups to create in our transaction
4586 * handle's new_bgs list to avoid exhausting the chunk block reserve
4587 * in extreme cases - like having a single transaction create many new
4588 * block groups when starting to write out the free space caches of all
4589 * the block groups that were made dirty during the lifetime of the
4592 if (trans
->can_flush_pending_bgs
&&
4593 trans
->chunk_bytes_reserved
>= (u64
)SZ_2M
) {
4594 btrfs_create_pending_block_groups(trans
);
4595 btrfs_trans_release_chunk_metadata(trans
);
4600 static int can_overcommit(struct btrfs_fs_info
*fs_info
,
4601 struct btrfs_space_info
*space_info
, u64 bytes
,
4602 enum btrfs_reserve_flush_enum flush
,
4605 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
4612 /* Don't overcommit when in mixed mode. */
4613 if (space_info
->flags
& BTRFS_BLOCK_GROUP_DATA
)
4617 profile
= btrfs_system_alloc_profile(fs_info
);
4619 profile
= btrfs_metadata_alloc_profile(fs_info
);
4621 used
= btrfs_space_info_used(space_info
, false);
4624 * We only want to allow over committing if we have lots of actual space
4625 * free, but if we don't have enough space to handle the global reserve
4626 * space then we could end up having a real enospc problem when trying
4627 * to allocate a chunk or some other such important allocation.
4629 spin_lock(&global_rsv
->lock
);
4630 space_size
= calc_global_rsv_need_space(global_rsv
);
4631 spin_unlock(&global_rsv
->lock
);
4632 if (used
+ space_size
>= space_info
->total_bytes
)
4635 used
+= space_info
->bytes_may_use
;
4637 avail
= atomic64_read(&fs_info
->free_chunk_space
);
4640 * If we have dup, raid1 or raid10 then only half of the free
4641 * space is actually useable. For raid56, the space info used
4642 * doesn't include the parity drive, so we don't have to
4645 factor
= btrfs_bg_type_to_factor(profile
);
4646 avail
= div_u64(avail
, factor
);
4649 * If we aren't flushing all things, let us overcommit up to
4650 * 1/2th of the space. If we can flush, don't let us overcommit
4651 * too much, let it overcommit up to 1/8 of the space.
4653 if (flush
== BTRFS_RESERVE_FLUSH_ALL
)
4658 if (used
+ bytes
< space_info
->total_bytes
+ avail
)
4663 static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info
*fs_info
,
4664 unsigned long nr_pages
, int nr_items
)
4666 struct super_block
*sb
= fs_info
->sb
;
4668 if (down_read_trylock(&sb
->s_umount
)) {
4669 writeback_inodes_sb_nr(sb
, nr_pages
, WB_REASON_FS_FREE_SPACE
);
4670 up_read(&sb
->s_umount
);
4673 * We needn't worry the filesystem going from r/w to r/o though
4674 * we don't acquire ->s_umount mutex, because the filesystem
4675 * should guarantee the delalloc inodes list be empty after
4676 * the filesystem is readonly(all dirty pages are written to
4679 btrfs_start_delalloc_roots(fs_info
, nr_items
);
4680 if (!current
->journal_info
)
4681 btrfs_wait_ordered_roots(fs_info
, nr_items
, 0, (u64
)-1);
4685 static inline u64
calc_reclaim_items_nr(struct btrfs_fs_info
*fs_info
,
4691 bytes
= btrfs_calc_trans_metadata_size(fs_info
, 1);
4692 nr
= div64_u64(to_reclaim
, bytes
);
4698 #define EXTENT_SIZE_PER_ITEM SZ_256K
4701 * shrink metadata reservation for delalloc
4703 static void shrink_delalloc(struct btrfs_fs_info
*fs_info
, u64 to_reclaim
,
4704 u64 orig
, bool wait_ordered
)
4706 struct btrfs_space_info
*space_info
;
4707 struct btrfs_trans_handle
*trans
;
4712 unsigned long nr_pages
;
4715 /* Calc the number of the pages we need flush for space reservation */
4716 items
= calc_reclaim_items_nr(fs_info
, to_reclaim
);
4717 to_reclaim
= items
* EXTENT_SIZE_PER_ITEM
;
4719 trans
= (struct btrfs_trans_handle
*)current
->journal_info
;
4720 space_info
= __find_space_info(fs_info
, BTRFS_BLOCK_GROUP_METADATA
);
4722 delalloc_bytes
= percpu_counter_sum_positive(
4723 &fs_info
->delalloc_bytes
);
4724 if (delalloc_bytes
== 0) {
4728 btrfs_wait_ordered_roots(fs_info
, items
, 0, (u64
)-1);
4733 while (delalloc_bytes
&& loops
< 3) {
4734 max_reclaim
= min(delalloc_bytes
, to_reclaim
);
4735 nr_pages
= max_reclaim
>> PAGE_SHIFT
;
4736 btrfs_writeback_inodes_sb_nr(fs_info
, nr_pages
, items
);
4738 * We need to wait for the async pages to actually start before
4741 max_reclaim
= atomic_read(&fs_info
->async_delalloc_pages
);
4745 if (max_reclaim
<= nr_pages
)
4748 max_reclaim
-= nr_pages
;
4750 wait_event(fs_info
->async_submit_wait
,
4751 atomic_read(&fs_info
->async_delalloc_pages
) <=
4754 spin_lock(&space_info
->lock
);
4755 if (list_empty(&space_info
->tickets
) &&
4756 list_empty(&space_info
->priority_tickets
)) {
4757 spin_unlock(&space_info
->lock
);
4760 spin_unlock(&space_info
->lock
);
4763 if (wait_ordered
&& !trans
) {
4764 btrfs_wait_ordered_roots(fs_info
, items
, 0, (u64
)-1);
4766 time_left
= schedule_timeout_killable(1);
4770 delalloc_bytes
= percpu_counter_sum_positive(
4771 &fs_info
->delalloc_bytes
);
4775 struct reserve_ticket
{
4778 struct list_head list
;
4779 wait_queue_head_t wait
;
4783 * maybe_commit_transaction - possibly commit the transaction if its ok to
4784 * @root - the root we're allocating for
4785 * @bytes - the number of bytes we want to reserve
4786 * @force - force the commit
4788 * This will check to make sure that committing the transaction will actually
4789 * get us somewhere and then commit the transaction if it does. Otherwise it
4790 * will return -ENOSPC.
4792 static int may_commit_transaction(struct btrfs_fs_info
*fs_info
,
4793 struct btrfs_space_info
*space_info
)
4795 struct reserve_ticket
*ticket
= NULL
;
4796 struct btrfs_block_rsv
*delayed_rsv
= &fs_info
->delayed_block_rsv
;
4797 struct btrfs_trans_handle
*trans
;
4800 trans
= (struct btrfs_trans_handle
*)current
->journal_info
;
4804 spin_lock(&space_info
->lock
);
4805 if (!list_empty(&space_info
->priority_tickets
))
4806 ticket
= list_first_entry(&space_info
->priority_tickets
,
4807 struct reserve_ticket
, list
);
4808 else if (!list_empty(&space_info
->tickets
))
4809 ticket
= list_first_entry(&space_info
->tickets
,
4810 struct reserve_ticket
, list
);
4811 bytes
= (ticket
) ? ticket
->bytes
: 0;
4812 spin_unlock(&space_info
->lock
);
4817 /* See if there is enough pinned space to make this reservation */
4818 if (__percpu_counter_compare(&space_info
->total_bytes_pinned
,
4820 BTRFS_TOTAL_BYTES_PINNED_BATCH
) >= 0)
4824 * See if there is some space in the delayed insertion reservation for
4827 if (space_info
!= delayed_rsv
->space_info
)
4830 spin_lock(&delayed_rsv
->lock
);
4831 if (delayed_rsv
->size
> bytes
)
4834 bytes
-= delayed_rsv
->size
;
4835 spin_unlock(&delayed_rsv
->lock
);
4837 if (__percpu_counter_compare(&space_info
->total_bytes_pinned
,
4839 BTRFS_TOTAL_BYTES_PINNED_BATCH
) < 0) {
4844 trans
= btrfs_join_transaction(fs_info
->extent_root
);
4848 return btrfs_commit_transaction(trans
);
4852 * Try to flush some data based on policy set by @state. This is only advisory
4853 * and may fail for various reasons. The caller is supposed to examine the
4854 * state of @space_info to detect the outcome.
4856 static void flush_space(struct btrfs_fs_info
*fs_info
,
4857 struct btrfs_space_info
*space_info
, u64 num_bytes
,
4860 struct btrfs_root
*root
= fs_info
->extent_root
;
4861 struct btrfs_trans_handle
*trans
;
4866 case FLUSH_DELAYED_ITEMS_NR
:
4867 case FLUSH_DELAYED_ITEMS
:
4868 if (state
== FLUSH_DELAYED_ITEMS_NR
)
4869 nr
= calc_reclaim_items_nr(fs_info
, num_bytes
) * 2;
4873 trans
= btrfs_join_transaction(root
);
4874 if (IS_ERR(trans
)) {
4875 ret
= PTR_ERR(trans
);
4878 ret
= btrfs_run_delayed_items_nr(trans
, nr
);
4879 btrfs_end_transaction(trans
);
4881 case FLUSH_DELALLOC
:
4882 case FLUSH_DELALLOC_WAIT
:
4883 shrink_delalloc(fs_info
, num_bytes
* 2, num_bytes
,
4884 state
== FLUSH_DELALLOC_WAIT
);
4887 trans
= btrfs_join_transaction(root
);
4888 if (IS_ERR(trans
)) {
4889 ret
= PTR_ERR(trans
);
4892 ret
= do_chunk_alloc(trans
,
4893 btrfs_metadata_alloc_profile(fs_info
),
4894 CHUNK_ALLOC_NO_FORCE
);
4895 btrfs_end_transaction(trans
);
4896 if (ret
> 0 || ret
== -ENOSPC
)
4900 ret
= may_commit_transaction(fs_info
, space_info
);
4907 trace_btrfs_flush_space(fs_info
, space_info
->flags
, num_bytes
, state
,
4913 btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info
*fs_info
,
4914 struct btrfs_space_info
*space_info
,
4917 struct reserve_ticket
*ticket
;
4922 list_for_each_entry(ticket
, &space_info
->tickets
, list
)
4923 to_reclaim
+= ticket
->bytes
;
4924 list_for_each_entry(ticket
, &space_info
->priority_tickets
, list
)
4925 to_reclaim
+= ticket
->bytes
;
4929 to_reclaim
= min_t(u64
, num_online_cpus() * SZ_1M
, SZ_16M
);
4930 if (can_overcommit(fs_info
, space_info
, to_reclaim
,
4931 BTRFS_RESERVE_FLUSH_ALL
, system_chunk
))
4934 used
= btrfs_space_info_used(space_info
, true);
4936 if (can_overcommit(fs_info
, space_info
, SZ_1M
,
4937 BTRFS_RESERVE_FLUSH_ALL
, system_chunk
))
4938 expected
= div_factor_fine(space_info
->total_bytes
, 95);
4940 expected
= div_factor_fine(space_info
->total_bytes
, 90);
4942 if (used
> expected
)
4943 to_reclaim
= used
- expected
;
4946 to_reclaim
= min(to_reclaim
, space_info
->bytes_may_use
+
4947 space_info
->bytes_reserved
);
4951 static inline int need_do_async_reclaim(struct btrfs_fs_info
*fs_info
,
4952 struct btrfs_space_info
*space_info
,
4953 u64 used
, bool system_chunk
)
4955 u64 thresh
= div_factor_fine(space_info
->total_bytes
, 98);
4957 /* If we're just plain full then async reclaim just slows us down. */
4958 if ((space_info
->bytes_used
+ space_info
->bytes_reserved
) >= thresh
)
4961 if (!btrfs_calc_reclaim_metadata_size(fs_info
, space_info
,
4965 return (used
>= thresh
&& !btrfs_fs_closing(fs_info
) &&
4966 !test_bit(BTRFS_FS_STATE_REMOUNTING
, &fs_info
->fs_state
));
4969 static void wake_all_tickets(struct list_head
*head
)
4971 struct reserve_ticket
*ticket
;
4973 while (!list_empty(head
)) {
4974 ticket
= list_first_entry(head
, struct reserve_ticket
, list
);
4975 list_del_init(&ticket
->list
);
4976 ticket
->error
= -ENOSPC
;
4977 wake_up(&ticket
->wait
);
4982 * This is for normal flushers, we can wait all goddamned day if we want to. We
4983 * will loop and continuously try to flush as long as we are making progress.
4984 * We count progress as clearing off tickets each time we have to loop.
4986 static void btrfs_async_reclaim_metadata_space(struct work_struct
*work
)
4988 struct btrfs_fs_info
*fs_info
;
4989 struct btrfs_space_info
*space_info
;
4992 int commit_cycles
= 0;
4993 u64 last_tickets_id
;
4995 fs_info
= container_of(work
, struct btrfs_fs_info
, async_reclaim_work
);
4996 space_info
= __find_space_info(fs_info
, BTRFS_BLOCK_GROUP_METADATA
);
4998 spin_lock(&space_info
->lock
);
4999 to_reclaim
= btrfs_calc_reclaim_metadata_size(fs_info
, space_info
,
5002 space_info
->flush
= 0;
5003 spin_unlock(&space_info
->lock
);
5006 last_tickets_id
= space_info
->tickets_id
;
5007 spin_unlock(&space_info
->lock
);
5009 flush_state
= FLUSH_DELAYED_ITEMS_NR
;
5011 flush_space(fs_info
, space_info
, to_reclaim
, flush_state
);
5012 spin_lock(&space_info
->lock
);
5013 if (list_empty(&space_info
->tickets
)) {
5014 space_info
->flush
= 0;
5015 spin_unlock(&space_info
->lock
);
5018 to_reclaim
= btrfs_calc_reclaim_metadata_size(fs_info
,
5021 if (last_tickets_id
== space_info
->tickets_id
) {
5024 last_tickets_id
= space_info
->tickets_id
;
5025 flush_state
= FLUSH_DELAYED_ITEMS_NR
;
5030 if (flush_state
> COMMIT_TRANS
) {
5032 if (commit_cycles
> 2) {
5033 wake_all_tickets(&space_info
->tickets
);
5034 space_info
->flush
= 0;
5036 flush_state
= FLUSH_DELAYED_ITEMS_NR
;
5039 spin_unlock(&space_info
->lock
);
5040 } while (flush_state
<= COMMIT_TRANS
);
5043 void btrfs_init_async_reclaim_work(struct work_struct
*work
)
5045 INIT_WORK(work
, btrfs_async_reclaim_metadata_space
);
5048 static void priority_reclaim_metadata_space(struct btrfs_fs_info
*fs_info
,
5049 struct btrfs_space_info
*space_info
,
5050 struct reserve_ticket
*ticket
)
5053 int flush_state
= FLUSH_DELAYED_ITEMS_NR
;
5055 spin_lock(&space_info
->lock
);
5056 to_reclaim
= btrfs_calc_reclaim_metadata_size(fs_info
, space_info
,
5059 spin_unlock(&space_info
->lock
);
5062 spin_unlock(&space_info
->lock
);
5065 flush_space(fs_info
, space_info
, to_reclaim
, flush_state
);
5067 spin_lock(&space_info
->lock
);
5068 if (ticket
->bytes
== 0) {
5069 spin_unlock(&space_info
->lock
);
5072 spin_unlock(&space_info
->lock
);
5075 * Priority flushers can't wait on delalloc without
5078 if (flush_state
== FLUSH_DELALLOC
||
5079 flush_state
== FLUSH_DELALLOC_WAIT
)
5080 flush_state
= ALLOC_CHUNK
;
5081 } while (flush_state
< COMMIT_TRANS
);
5084 static int wait_reserve_ticket(struct btrfs_fs_info
*fs_info
,
5085 struct btrfs_space_info
*space_info
,
5086 struct reserve_ticket
*ticket
, u64 orig_bytes
)
5092 spin_lock(&space_info
->lock
);
5093 while (ticket
->bytes
> 0 && ticket
->error
== 0) {
5094 ret
= prepare_to_wait_event(&ticket
->wait
, &wait
, TASK_KILLABLE
);
5099 spin_unlock(&space_info
->lock
);
5103 finish_wait(&ticket
->wait
, &wait
);
5104 spin_lock(&space_info
->lock
);
5107 ret
= ticket
->error
;
5108 if (!list_empty(&ticket
->list
))
5109 list_del_init(&ticket
->list
);
5110 if (ticket
->bytes
&& ticket
->bytes
< orig_bytes
) {
5111 u64 num_bytes
= orig_bytes
- ticket
->bytes
;
5112 space_info
->bytes_may_use
-= num_bytes
;
5113 trace_btrfs_space_reservation(fs_info
, "space_info",
5114 space_info
->flags
, num_bytes
, 0);
5116 spin_unlock(&space_info
->lock
);
5122 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5123 * @root - the root we're allocating for
5124 * @space_info - the space info we want to allocate from
5125 * @orig_bytes - the number of bytes we want
5126 * @flush - whether or not we can flush to make our reservation
5128 * This will reserve orig_bytes number of bytes from the space info associated
5129 * with the block_rsv. If there is not enough space it will make an attempt to
5130 * flush out space to make room. It will do this by flushing delalloc if
5131 * possible or committing the transaction. If flush is 0 then no attempts to
5132 * regain reservations will be made and this will fail if there is not enough
5135 static int __reserve_metadata_bytes(struct btrfs_fs_info
*fs_info
,
5136 struct btrfs_space_info
*space_info
,
5138 enum btrfs_reserve_flush_enum flush
,
5141 struct reserve_ticket ticket
;
5146 ASSERT(!current
->journal_info
|| flush
!= BTRFS_RESERVE_FLUSH_ALL
);
5148 spin_lock(&space_info
->lock
);
5150 used
= btrfs_space_info_used(space_info
, true);
5153 * If we have enough space then hooray, make our reservation and carry
5154 * on. If not see if we can overcommit, and if we can, hooray carry on.
5155 * If not things get more complicated.
5157 if (used
+ orig_bytes
<= space_info
->total_bytes
) {
5158 space_info
->bytes_may_use
+= orig_bytes
;
5159 trace_btrfs_space_reservation(fs_info
, "space_info",
5160 space_info
->flags
, orig_bytes
, 1);
5162 } else if (can_overcommit(fs_info
, space_info
, orig_bytes
, flush
,
5164 space_info
->bytes_may_use
+= orig_bytes
;
5165 trace_btrfs_space_reservation(fs_info
, "space_info",
5166 space_info
->flags
, orig_bytes
, 1);
5171 * If we couldn't make a reservation then setup our reservation ticket
5172 * and kick the async worker if it's not already running.
5174 * If we are a priority flusher then we just need to add our ticket to
5175 * the list and we will do our own flushing further down.
5177 if (ret
&& flush
!= BTRFS_RESERVE_NO_FLUSH
) {
5178 ticket
.bytes
= orig_bytes
;
5180 init_waitqueue_head(&ticket
.wait
);
5181 if (flush
== BTRFS_RESERVE_FLUSH_ALL
) {
5182 list_add_tail(&ticket
.list
, &space_info
->tickets
);
5183 if (!space_info
->flush
) {
5184 space_info
->flush
= 1;
5185 trace_btrfs_trigger_flush(fs_info
,
5189 queue_work(system_unbound_wq
,
5190 &fs_info
->async_reclaim_work
);
5193 list_add_tail(&ticket
.list
,
5194 &space_info
->priority_tickets
);
5196 } else if (!ret
&& space_info
->flags
& BTRFS_BLOCK_GROUP_METADATA
) {
5199 * We will do the space reservation dance during log replay,
5200 * which means we won't have fs_info->fs_root set, so don't do
5201 * the async reclaim as we will panic.
5203 if (!test_bit(BTRFS_FS_LOG_RECOVERING
, &fs_info
->flags
) &&
5204 need_do_async_reclaim(fs_info
, space_info
,
5205 used
, system_chunk
) &&
5206 !work_busy(&fs_info
->async_reclaim_work
)) {
5207 trace_btrfs_trigger_flush(fs_info
, space_info
->flags
,
5208 orig_bytes
, flush
, "preempt");
5209 queue_work(system_unbound_wq
,
5210 &fs_info
->async_reclaim_work
);
5213 spin_unlock(&space_info
->lock
);
5214 if (!ret
|| flush
== BTRFS_RESERVE_NO_FLUSH
)
5217 if (flush
== BTRFS_RESERVE_FLUSH_ALL
)
5218 return wait_reserve_ticket(fs_info
, space_info
, &ticket
,
5222 priority_reclaim_metadata_space(fs_info
, space_info
, &ticket
);
5223 spin_lock(&space_info
->lock
);
5225 if (ticket
.bytes
< orig_bytes
) {
5226 u64 num_bytes
= orig_bytes
- ticket
.bytes
;
5227 space_info
->bytes_may_use
-= num_bytes
;
5228 trace_btrfs_space_reservation(fs_info
, "space_info",
5233 list_del_init(&ticket
.list
);
5236 spin_unlock(&space_info
->lock
);
5237 ASSERT(list_empty(&ticket
.list
));
5242 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5243 * @root - the root we're allocating for
5244 * @block_rsv - the block_rsv we're allocating for
5245 * @orig_bytes - the number of bytes we want
5246 * @flush - whether or not we can flush to make our reservation
5248 * This will reserve orgi_bytes number of bytes from the space info associated
5249 * with the block_rsv. If there is not enough space it will make an attempt to
5250 * flush out space to make room. It will do this by flushing delalloc if
5251 * possible or committing the transaction. If flush is 0 then no attempts to
5252 * regain reservations will be made and this will fail if there is not enough
5255 static int reserve_metadata_bytes(struct btrfs_root
*root
,
5256 struct btrfs_block_rsv
*block_rsv
,
5258 enum btrfs_reserve_flush_enum flush
)
5260 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
5261 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
5263 bool system_chunk
= (root
== fs_info
->chunk_root
);
5265 ret
= __reserve_metadata_bytes(fs_info
, block_rsv
->space_info
,
5266 orig_bytes
, flush
, system_chunk
);
5267 if (ret
== -ENOSPC
&&
5268 unlikely(root
->orphan_cleanup_state
== ORPHAN_CLEANUP_STARTED
)) {
5269 if (block_rsv
!= global_rsv
&&
5270 !block_rsv_use_bytes(global_rsv
, orig_bytes
))
5273 if (ret
== -ENOSPC
) {
5274 trace_btrfs_space_reservation(fs_info
, "space_info:enospc",
5275 block_rsv
->space_info
->flags
,
5278 if (btrfs_test_opt(fs_info
, ENOSPC_DEBUG
))
5279 dump_space_info(fs_info
, block_rsv
->space_info
,
5285 static struct btrfs_block_rsv
*get_block_rsv(
5286 const struct btrfs_trans_handle
*trans
,
5287 const struct btrfs_root
*root
)
5289 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
5290 struct btrfs_block_rsv
*block_rsv
= NULL
;
5292 if (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) ||
5293 (root
== fs_info
->csum_root
&& trans
->adding_csums
) ||
5294 (root
== fs_info
->uuid_root
))
5295 block_rsv
= trans
->block_rsv
;
5298 block_rsv
= root
->block_rsv
;
5301 block_rsv
= &fs_info
->empty_block_rsv
;
5306 static int block_rsv_use_bytes(struct btrfs_block_rsv
*block_rsv
,
5310 spin_lock(&block_rsv
->lock
);
5311 if (block_rsv
->reserved
>= num_bytes
) {
5312 block_rsv
->reserved
-= num_bytes
;
5313 if (block_rsv
->reserved
< block_rsv
->size
)
5314 block_rsv
->full
= 0;
5317 spin_unlock(&block_rsv
->lock
);
5321 static void block_rsv_add_bytes(struct btrfs_block_rsv
*block_rsv
,
5322 u64 num_bytes
, bool update_size
)
5324 spin_lock(&block_rsv
->lock
);
5325 block_rsv
->reserved
+= num_bytes
;
5327 block_rsv
->size
+= num_bytes
;
5328 else if (block_rsv
->reserved
>= block_rsv
->size
)
5329 block_rsv
->full
= 1;
5330 spin_unlock(&block_rsv
->lock
);
5333 int btrfs_cond_migrate_bytes(struct btrfs_fs_info
*fs_info
,
5334 struct btrfs_block_rsv
*dest
, u64 num_bytes
,
5337 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
5340 if (global_rsv
->space_info
!= dest
->space_info
)
5343 spin_lock(&global_rsv
->lock
);
5344 min_bytes
= div_factor(global_rsv
->size
, min_factor
);
5345 if (global_rsv
->reserved
< min_bytes
+ num_bytes
) {
5346 spin_unlock(&global_rsv
->lock
);
5349 global_rsv
->reserved
-= num_bytes
;
5350 if (global_rsv
->reserved
< global_rsv
->size
)
5351 global_rsv
->full
= 0;
5352 spin_unlock(&global_rsv
->lock
);
5354 block_rsv_add_bytes(dest
, num_bytes
, true);
5359 * This is for space we already have accounted in space_info->bytes_may_use, so
5360 * basically when we're returning space from block_rsv's.
5362 static void space_info_add_old_bytes(struct btrfs_fs_info
*fs_info
,
5363 struct btrfs_space_info
*space_info
,
5366 struct reserve_ticket
*ticket
;
5367 struct list_head
*head
;
5369 enum btrfs_reserve_flush_enum flush
= BTRFS_RESERVE_NO_FLUSH
;
5370 bool check_overcommit
= false;
5372 spin_lock(&space_info
->lock
);
5373 head
= &space_info
->priority_tickets
;
5376 * If we are over our limit then we need to check and see if we can
5377 * overcommit, and if we can't then we just need to free up our space
5378 * and not satisfy any requests.
5380 used
= btrfs_space_info_used(space_info
, true);
5381 if (used
- num_bytes
>= space_info
->total_bytes
)
5382 check_overcommit
= true;
5384 while (!list_empty(head
) && num_bytes
) {
5385 ticket
= list_first_entry(head
, struct reserve_ticket
,
5388 * We use 0 bytes because this space is already reserved, so
5389 * adding the ticket space would be a double count.
5391 if (check_overcommit
&&
5392 !can_overcommit(fs_info
, space_info
, 0, flush
, false))
5394 if (num_bytes
>= ticket
->bytes
) {
5395 list_del_init(&ticket
->list
);
5396 num_bytes
-= ticket
->bytes
;
5398 space_info
->tickets_id
++;
5399 wake_up(&ticket
->wait
);
5401 ticket
->bytes
-= num_bytes
;
5406 if (num_bytes
&& head
== &space_info
->priority_tickets
) {
5407 head
= &space_info
->tickets
;
5408 flush
= BTRFS_RESERVE_FLUSH_ALL
;
5411 space_info
->bytes_may_use
-= num_bytes
;
5412 trace_btrfs_space_reservation(fs_info
, "space_info",
5413 space_info
->flags
, num_bytes
, 0);
5414 spin_unlock(&space_info
->lock
);
5418 * This is for newly allocated space that isn't accounted in
5419 * space_info->bytes_may_use yet. So if we allocate a chunk or unpin an extent
5420 * we use this helper.
5422 static void space_info_add_new_bytes(struct btrfs_fs_info
*fs_info
,
5423 struct btrfs_space_info
*space_info
,
5426 struct reserve_ticket
*ticket
;
5427 struct list_head
*head
= &space_info
->priority_tickets
;
5430 while (!list_empty(head
) && num_bytes
) {
5431 ticket
= list_first_entry(head
, struct reserve_ticket
,
5433 if (num_bytes
>= ticket
->bytes
) {
5434 trace_btrfs_space_reservation(fs_info
, "space_info",
5437 list_del_init(&ticket
->list
);
5438 num_bytes
-= ticket
->bytes
;
5439 space_info
->bytes_may_use
+= ticket
->bytes
;
5441 space_info
->tickets_id
++;
5442 wake_up(&ticket
->wait
);
5444 trace_btrfs_space_reservation(fs_info
, "space_info",
5447 space_info
->bytes_may_use
+= num_bytes
;
5448 ticket
->bytes
-= num_bytes
;
5453 if (num_bytes
&& head
== &space_info
->priority_tickets
) {
5454 head
= &space_info
->tickets
;
5459 static u64
block_rsv_release_bytes(struct btrfs_fs_info
*fs_info
,
5460 struct btrfs_block_rsv
*block_rsv
,
5461 struct btrfs_block_rsv
*dest
, u64 num_bytes
,
5462 u64
*qgroup_to_release_ret
)
5464 struct btrfs_space_info
*space_info
= block_rsv
->space_info
;
5465 u64 qgroup_to_release
= 0;
5468 spin_lock(&block_rsv
->lock
);
5469 if (num_bytes
== (u64
)-1) {
5470 num_bytes
= block_rsv
->size
;
5471 qgroup_to_release
= block_rsv
->qgroup_rsv_size
;
5473 block_rsv
->size
-= num_bytes
;
5474 if (block_rsv
->reserved
>= block_rsv
->size
) {
5475 num_bytes
= block_rsv
->reserved
- block_rsv
->size
;
5476 block_rsv
->reserved
= block_rsv
->size
;
5477 block_rsv
->full
= 1;
5481 if (block_rsv
->qgroup_rsv_reserved
>= block_rsv
->qgroup_rsv_size
) {
5482 qgroup_to_release
= block_rsv
->qgroup_rsv_reserved
-
5483 block_rsv
->qgroup_rsv_size
;
5484 block_rsv
->qgroup_rsv_reserved
= block_rsv
->qgroup_rsv_size
;
5486 qgroup_to_release
= 0;
5488 spin_unlock(&block_rsv
->lock
);
5491 if (num_bytes
> 0) {
5493 spin_lock(&dest
->lock
);
5497 bytes_to_add
= dest
->size
- dest
->reserved
;
5498 bytes_to_add
= min(num_bytes
, bytes_to_add
);
5499 dest
->reserved
+= bytes_to_add
;
5500 if (dest
->reserved
>= dest
->size
)
5502 num_bytes
-= bytes_to_add
;
5504 spin_unlock(&dest
->lock
);
5507 space_info_add_old_bytes(fs_info
, space_info
,
5510 if (qgroup_to_release_ret
)
5511 *qgroup_to_release_ret
= qgroup_to_release
;
5515 int btrfs_block_rsv_migrate(struct btrfs_block_rsv
*src
,
5516 struct btrfs_block_rsv
*dst
, u64 num_bytes
,
5521 ret
= block_rsv_use_bytes(src
, num_bytes
);
5525 block_rsv_add_bytes(dst
, num_bytes
, update_size
);
5529 void btrfs_init_block_rsv(struct btrfs_block_rsv
*rsv
, unsigned short type
)
5531 memset(rsv
, 0, sizeof(*rsv
));
5532 spin_lock_init(&rsv
->lock
);
5536 void btrfs_init_metadata_block_rsv(struct btrfs_fs_info
*fs_info
,
5537 struct btrfs_block_rsv
*rsv
,
5538 unsigned short type
)
5540 btrfs_init_block_rsv(rsv
, type
);
5541 rsv
->space_info
= __find_space_info(fs_info
,
5542 BTRFS_BLOCK_GROUP_METADATA
);
5545 struct btrfs_block_rsv
*btrfs_alloc_block_rsv(struct btrfs_fs_info
*fs_info
,
5546 unsigned short type
)
5548 struct btrfs_block_rsv
*block_rsv
;
5550 block_rsv
= kmalloc(sizeof(*block_rsv
), GFP_NOFS
);
5554 btrfs_init_metadata_block_rsv(fs_info
, block_rsv
, type
);
5558 void btrfs_free_block_rsv(struct btrfs_fs_info
*fs_info
,
5559 struct btrfs_block_rsv
*rsv
)
5563 btrfs_block_rsv_release(fs_info
, rsv
, (u64
)-1);
5567 int btrfs_block_rsv_add(struct btrfs_root
*root
,
5568 struct btrfs_block_rsv
*block_rsv
, u64 num_bytes
,
5569 enum btrfs_reserve_flush_enum flush
)
5576 ret
= reserve_metadata_bytes(root
, block_rsv
, num_bytes
, flush
);
5578 block_rsv_add_bytes(block_rsv
, num_bytes
, true);
5583 int btrfs_block_rsv_check(struct btrfs_block_rsv
*block_rsv
, int min_factor
)
5591 spin_lock(&block_rsv
->lock
);
5592 num_bytes
= div_factor(block_rsv
->size
, min_factor
);
5593 if (block_rsv
->reserved
>= num_bytes
)
5595 spin_unlock(&block_rsv
->lock
);
5600 int btrfs_block_rsv_refill(struct btrfs_root
*root
,
5601 struct btrfs_block_rsv
*block_rsv
, u64 min_reserved
,
5602 enum btrfs_reserve_flush_enum flush
)
5610 spin_lock(&block_rsv
->lock
);
5611 num_bytes
= min_reserved
;
5612 if (block_rsv
->reserved
>= num_bytes
)
5615 num_bytes
-= block_rsv
->reserved
;
5616 spin_unlock(&block_rsv
->lock
);
5621 ret
= reserve_metadata_bytes(root
, block_rsv
, num_bytes
, flush
);
5623 block_rsv_add_bytes(block_rsv
, num_bytes
, false);
5631 * btrfs_inode_rsv_refill - refill the inode block rsv.
5632 * @inode - the inode we are refilling.
5633 * @flush - the flusing restriction.
5635 * Essentially the same as btrfs_block_rsv_refill, except it uses the
5636 * block_rsv->size as the minimum size. We'll either refill the missing amount
5637 * or return if we already have enough space. This will also handle the resreve
5638 * tracepoint for the reserved amount.
5640 static int btrfs_inode_rsv_refill(struct btrfs_inode
*inode
,
5641 enum btrfs_reserve_flush_enum flush
)
5643 struct btrfs_root
*root
= inode
->root
;
5644 struct btrfs_block_rsv
*block_rsv
= &inode
->block_rsv
;
5646 u64 qgroup_num_bytes
= 0;
5649 spin_lock(&block_rsv
->lock
);
5650 if (block_rsv
->reserved
< block_rsv
->size
)
5651 num_bytes
= block_rsv
->size
- block_rsv
->reserved
;
5652 if (block_rsv
->qgroup_rsv_reserved
< block_rsv
->qgroup_rsv_size
)
5653 qgroup_num_bytes
= block_rsv
->qgroup_rsv_size
-
5654 block_rsv
->qgroup_rsv_reserved
;
5655 spin_unlock(&block_rsv
->lock
);
5660 ret
= btrfs_qgroup_reserve_meta_prealloc(root
, qgroup_num_bytes
, true);
5663 ret
= reserve_metadata_bytes(root
, block_rsv
, num_bytes
, flush
);
5665 block_rsv_add_bytes(block_rsv
, num_bytes
, false);
5666 trace_btrfs_space_reservation(root
->fs_info
, "delalloc",
5667 btrfs_ino(inode
), num_bytes
, 1);
5669 /* Don't forget to increase qgroup_rsv_reserved */
5670 spin_lock(&block_rsv
->lock
);
5671 block_rsv
->qgroup_rsv_reserved
+= qgroup_num_bytes
;
5672 spin_unlock(&block_rsv
->lock
);
5674 btrfs_qgroup_free_meta_prealloc(root
, qgroup_num_bytes
);
5679 * btrfs_inode_rsv_release - release any excessive reservation.
5680 * @inode - the inode we need to release from.
5681 * @qgroup_free - free or convert qgroup meta.
5682 * Unlike normal operation, qgroup meta reservation needs to know if we are
5683 * freeing qgroup reservation or just converting it into per-trans. Normally
5684 * @qgroup_free is true for error handling, and false for normal release.
5686 * This is the same as btrfs_block_rsv_release, except that it handles the
5687 * tracepoint for the reservation.
5689 static void btrfs_inode_rsv_release(struct btrfs_inode
*inode
, bool qgroup_free
)
5691 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
5692 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
5693 struct btrfs_block_rsv
*block_rsv
= &inode
->block_rsv
;
5695 u64 qgroup_to_release
= 0;
5698 * Since we statically set the block_rsv->size we just want to say we
5699 * are releasing 0 bytes, and then we'll just get the reservation over
5702 released
= block_rsv_release_bytes(fs_info
, block_rsv
, global_rsv
, 0,
5703 &qgroup_to_release
);
5705 trace_btrfs_space_reservation(fs_info
, "delalloc",
5706 btrfs_ino(inode
), released
, 0);
5708 btrfs_qgroup_free_meta_prealloc(inode
->root
, qgroup_to_release
);
5710 btrfs_qgroup_convert_reserved_meta(inode
->root
,
5714 void btrfs_block_rsv_release(struct btrfs_fs_info
*fs_info
,
5715 struct btrfs_block_rsv
*block_rsv
,
5718 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
5720 if (global_rsv
== block_rsv
||
5721 block_rsv
->space_info
!= global_rsv
->space_info
)
5723 block_rsv_release_bytes(fs_info
, block_rsv
, global_rsv
, num_bytes
, NULL
);
5726 static void update_global_block_rsv(struct btrfs_fs_info
*fs_info
)
5728 struct btrfs_block_rsv
*block_rsv
= &fs_info
->global_block_rsv
;
5729 struct btrfs_space_info
*sinfo
= block_rsv
->space_info
;
5733 * The global block rsv is based on the size of the extent tree, the
5734 * checksum tree and the root tree. If the fs is empty we want to set
5735 * it to a minimal amount for safety.
5737 num_bytes
= btrfs_root_used(&fs_info
->extent_root
->root_item
) +
5738 btrfs_root_used(&fs_info
->csum_root
->root_item
) +
5739 btrfs_root_used(&fs_info
->tree_root
->root_item
);
5740 num_bytes
= max_t(u64
, num_bytes
, SZ_16M
);
5742 spin_lock(&sinfo
->lock
);
5743 spin_lock(&block_rsv
->lock
);
5745 block_rsv
->size
= min_t(u64
, num_bytes
, SZ_512M
);
5747 if (block_rsv
->reserved
< block_rsv
->size
) {
5748 num_bytes
= btrfs_space_info_used(sinfo
, true);
5749 if (sinfo
->total_bytes
> num_bytes
) {
5750 num_bytes
= sinfo
->total_bytes
- num_bytes
;
5751 num_bytes
= min(num_bytes
,
5752 block_rsv
->size
- block_rsv
->reserved
);
5753 block_rsv
->reserved
+= num_bytes
;
5754 sinfo
->bytes_may_use
+= num_bytes
;
5755 trace_btrfs_space_reservation(fs_info
, "space_info",
5756 sinfo
->flags
, num_bytes
,
5759 } else if (block_rsv
->reserved
> block_rsv
->size
) {
5760 num_bytes
= block_rsv
->reserved
- block_rsv
->size
;
5761 sinfo
->bytes_may_use
-= num_bytes
;
5762 trace_btrfs_space_reservation(fs_info
, "space_info",
5763 sinfo
->flags
, num_bytes
, 0);
5764 block_rsv
->reserved
= block_rsv
->size
;
5767 if (block_rsv
->reserved
== block_rsv
->size
)
5768 block_rsv
->full
= 1;
5770 block_rsv
->full
= 0;
5772 spin_unlock(&block_rsv
->lock
);
5773 spin_unlock(&sinfo
->lock
);
5776 static void init_global_block_rsv(struct btrfs_fs_info
*fs_info
)
5778 struct btrfs_space_info
*space_info
;
5780 space_info
= __find_space_info(fs_info
, BTRFS_BLOCK_GROUP_SYSTEM
);
5781 fs_info
->chunk_block_rsv
.space_info
= space_info
;
5783 space_info
= __find_space_info(fs_info
, BTRFS_BLOCK_GROUP_METADATA
);
5784 fs_info
->global_block_rsv
.space_info
= space_info
;
5785 fs_info
->trans_block_rsv
.space_info
= space_info
;
5786 fs_info
->empty_block_rsv
.space_info
= space_info
;
5787 fs_info
->delayed_block_rsv
.space_info
= space_info
;
5789 fs_info
->extent_root
->block_rsv
= &fs_info
->global_block_rsv
;
5790 fs_info
->csum_root
->block_rsv
= &fs_info
->global_block_rsv
;
5791 fs_info
->dev_root
->block_rsv
= &fs_info
->global_block_rsv
;
5792 fs_info
->tree_root
->block_rsv
= &fs_info
->global_block_rsv
;
5793 if (fs_info
->quota_root
)
5794 fs_info
->quota_root
->block_rsv
= &fs_info
->global_block_rsv
;
5795 fs_info
->chunk_root
->block_rsv
= &fs_info
->chunk_block_rsv
;
5797 update_global_block_rsv(fs_info
);
5800 static void release_global_block_rsv(struct btrfs_fs_info
*fs_info
)
5802 block_rsv_release_bytes(fs_info
, &fs_info
->global_block_rsv
, NULL
,
5804 WARN_ON(fs_info
->trans_block_rsv
.size
> 0);
5805 WARN_ON(fs_info
->trans_block_rsv
.reserved
> 0);
5806 WARN_ON(fs_info
->chunk_block_rsv
.size
> 0);
5807 WARN_ON(fs_info
->chunk_block_rsv
.reserved
> 0);
5808 WARN_ON(fs_info
->delayed_block_rsv
.size
> 0);
5809 WARN_ON(fs_info
->delayed_block_rsv
.reserved
> 0);
5814 * To be called after all the new block groups attached to the transaction
5815 * handle have been created (btrfs_create_pending_block_groups()).
5817 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle
*trans
)
5819 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
5821 if (!trans
->chunk_bytes_reserved
)
5824 WARN_ON_ONCE(!list_empty(&trans
->new_bgs
));
5826 block_rsv_release_bytes(fs_info
, &fs_info
->chunk_block_rsv
, NULL
,
5827 trans
->chunk_bytes_reserved
, NULL
);
5828 trans
->chunk_bytes_reserved
= 0;
5832 * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
5833 * root: the root of the parent directory
5834 * rsv: block reservation
5835 * items: the number of items that we need do reservation
5836 * use_global_rsv: allow fallback to the global block reservation
5838 * This function is used to reserve the space for snapshot/subvolume
5839 * creation and deletion. Those operations are different with the
5840 * common file/directory operations, they change two fs/file trees
5841 * and root tree, the number of items that the qgroup reserves is
5842 * different with the free space reservation. So we can not use
5843 * the space reservation mechanism in start_transaction().
5845 int btrfs_subvolume_reserve_metadata(struct btrfs_root
*root
,
5846 struct btrfs_block_rsv
*rsv
, int items
,
5847 bool use_global_rsv
)
5849 u64 qgroup_num_bytes
= 0;
5852 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
5853 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
5855 if (test_bit(BTRFS_FS_QUOTA_ENABLED
, &fs_info
->flags
)) {
5856 /* One for parent inode, two for dir entries */
5857 qgroup_num_bytes
= 3 * fs_info
->nodesize
;
5858 ret
= btrfs_qgroup_reserve_meta_prealloc(root
,
5859 qgroup_num_bytes
, true);
5864 num_bytes
= btrfs_calc_trans_metadata_size(fs_info
, items
);
5865 rsv
->space_info
= __find_space_info(fs_info
,
5866 BTRFS_BLOCK_GROUP_METADATA
);
5867 ret
= btrfs_block_rsv_add(root
, rsv
, num_bytes
,
5868 BTRFS_RESERVE_FLUSH_ALL
);
5870 if (ret
== -ENOSPC
&& use_global_rsv
)
5871 ret
= btrfs_block_rsv_migrate(global_rsv
, rsv
, num_bytes
, true);
5873 if (ret
&& qgroup_num_bytes
)
5874 btrfs_qgroup_free_meta_prealloc(root
, qgroup_num_bytes
);
5879 void btrfs_subvolume_release_metadata(struct btrfs_fs_info
*fs_info
,
5880 struct btrfs_block_rsv
*rsv
)
5882 btrfs_block_rsv_release(fs_info
, rsv
, (u64
)-1);
5885 static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info
*fs_info
,
5886 struct btrfs_inode
*inode
)
5888 struct btrfs_block_rsv
*block_rsv
= &inode
->block_rsv
;
5889 u64 reserve_size
= 0;
5890 u64 qgroup_rsv_size
= 0;
5892 unsigned outstanding_extents
;
5894 lockdep_assert_held(&inode
->lock
);
5895 outstanding_extents
= inode
->outstanding_extents
;
5896 if (outstanding_extents
)
5897 reserve_size
= btrfs_calc_trans_metadata_size(fs_info
,
5898 outstanding_extents
+ 1);
5899 csum_leaves
= btrfs_csum_bytes_to_leaves(fs_info
,
5901 reserve_size
+= btrfs_calc_trans_metadata_size(fs_info
,
5904 * For qgroup rsv, the calculation is very simple:
5905 * account one nodesize for each outstanding extent
5907 * This is overestimating in most cases.
5909 qgroup_rsv_size
= outstanding_extents
* fs_info
->nodesize
;
5911 spin_lock(&block_rsv
->lock
);
5912 block_rsv
->size
= reserve_size
;
5913 block_rsv
->qgroup_rsv_size
= qgroup_rsv_size
;
5914 spin_unlock(&block_rsv
->lock
);
5917 int btrfs_delalloc_reserve_metadata(struct btrfs_inode
*inode
, u64 num_bytes
)
5919 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
5920 unsigned nr_extents
;
5921 enum btrfs_reserve_flush_enum flush
= BTRFS_RESERVE_FLUSH_ALL
;
5923 bool delalloc_lock
= true;
5925 /* If we are a free space inode we need to not flush since we will be in
5926 * the middle of a transaction commit. We also don't need the delalloc
5927 * mutex since we won't race with anybody. We need this mostly to make
5928 * lockdep shut its filthy mouth.
5930 * If we have a transaction open (can happen if we call truncate_block
5931 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
5933 if (btrfs_is_free_space_inode(inode
)) {
5934 flush
= BTRFS_RESERVE_NO_FLUSH
;
5935 delalloc_lock
= false;
5937 if (current
->journal_info
)
5938 flush
= BTRFS_RESERVE_FLUSH_LIMIT
;
5940 if (btrfs_transaction_in_commit(fs_info
))
5941 schedule_timeout(1);
5945 mutex_lock(&inode
->delalloc_mutex
);
5947 num_bytes
= ALIGN(num_bytes
, fs_info
->sectorsize
);
5949 /* Add our new extents and calculate the new rsv size. */
5950 spin_lock(&inode
->lock
);
5951 nr_extents
= count_max_extents(num_bytes
);
5952 btrfs_mod_outstanding_extents(inode
, nr_extents
);
5953 inode
->csum_bytes
+= num_bytes
;
5954 btrfs_calculate_inode_block_rsv_size(fs_info
, inode
);
5955 spin_unlock(&inode
->lock
);
5957 ret
= btrfs_inode_rsv_refill(inode
, flush
);
5962 mutex_unlock(&inode
->delalloc_mutex
);
5966 spin_lock(&inode
->lock
);
5967 nr_extents
= count_max_extents(num_bytes
);
5968 btrfs_mod_outstanding_extents(inode
, -nr_extents
);
5969 inode
->csum_bytes
-= num_bytes
;
5970 btrfs_calculate_inode_block_rsv_size(fs_info
, inode
);
5971 spin_unlock(&inode
->lock
);
5973 btrfs_inode_rsv_release(inode
, true);
5975 mutex_unlock(&inode
->delalloc_mutex
);
5980 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
5981 * @inode: the inode to release the reservation for.
5982 * @num_bytes: the number of bytes we are releasing.
5983 * @qgroup_free: free qgroup reservation or convert it to per-trans reservation
5985 * This will release the metadata reservation for an inode. This can be called
5986 * once we complete IO for a given set of bytes to release their metadata
5987 * reservations, or on error for the same reason.
5989 void btrfs_delalloc_release_metadata(struct btrfs_inode
*inode
, u64 num_bytes
,
5992 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
5994 num_bytes
= ALIGN(num_bytes
, fs_info
->sectorsize
);
5995 spin_lock(&inode
->lock
);
5996 inode
->csum_bytes
-= num_bytes
;
5997 btrfs_calculate_inode_block_rsv_size(fs_info
, inode
);
5998 spin_unlock(&inode
->lock
);
6000 if (btrfs_is_testing(fs_info
))
6003 btrfs_inode_rsv_release(inode
, qgroup_free
);
6007 * btrfs_delalloc_release_extents - release our outstanding_extents
6008 * @inode: the inode to balance the reservation for.
6009 * @num_bytes: the number of bytes we originally reserved with
6010 * @qgroup_free: do we need to free qgroup meta reservation or convert them.
6012 * When we reserve space we increase outstanding_extents for the extents we may
6013 * add. Once we've set the range as delalloc or created our ordered extents we
6014 * have outstanding_extents to track the real usage, so we use this to free our
6015 * temporarily tracked outstanding_extents. This _must_ be used in conjunction
6016 * with btrfs_delalloc_reserve_metadata.
6018 void btrfs_delalloc_release_extents(struct btrfs_inode
*inode
, u64 num_bytes
,
6021 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
6022 unsigned num_extents
;
6024 spin_lock(&inode
->lock
);
6025 num_extents
= count_max_extents(num_bytes
);
6026 btrfs_mod_outstanding_extents(inode
, -num_extents
);
6027 btrfs_calculate_inode_block_rsv_size(fs_info
, inode
);
6028 spin_unlock(&inode
->lock
);
6030 if (btrfs_is_testing(fs_info
))
6033 btrfs_inode_rsv_release(inode
, qgroup_free
);
6037 * btrfs_delalloc_reserve_space - reserve data and metadata space for
6039 * @inode: inode we're writing to
6040 * @start: start range we are writing to
6041 * @len: how long the range we are writing to
6042 * @reserved: mandatory parameter, record actually reserved qgroup ranges of
6043 * current reservation.
6045 * This will do the following things
6047 * o reserve space in data space info for num bytes
6048 * and reserve precious corresponding qgroup space
6049 * (Done in check_data_free_space)
6051 * o reserve space for metadata space, based on the number of outstanding
6052 * extents and how much csums will be needed
6053 * also reserve metadata space in a per root over-reserve method.
6054 * o add to the inodes->delalloc_bytes
6055 * o add it to the fs_info's delalloc inodes list.
6056 * (Above 3 all done in delalloc_reserve_metadata)
6058 * Return 0 for success
6059 * Return <0 for error(-ENOSPC or -EQUOT)
6061 int btrfs_delalloc_reserve_space(struct inode
*inode
,
6062 struct extent_changeset
**reserved
, u64 start
, u64 len
)
6066 ret
= btrfs_check_data_free_space(inode
, reserved
, start
, len
);
6069 ret
= btrfs_delalloc_reserve_metadata(BTRFS_I(inode
), len
);
6071 btrfs_free_reserved_data_space(inode
, *reserved
, start
, len
);
6076 * btrfs_delalloc_release_space - release data and metadata space for delalloc
6077 * @inode: inode we're releasing space for
6078 * @start: start position of the space already reserved
6079 * @len: the len of the space already reserved
6080 * @release_bytes: the len of the space we consumed or didn't use
6082 * This function will release the metadata space that was not used and will
6083 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
6084 * list if there are no delalloc bytes left.
6085 * Also it will handle the qgroup reserved space.
6087 void btrfs_delalloc_release_space(struct inode
*inode
,
6088 struct extent_changeset
*reserved
,
6089 u64 start
, u64 len
, bool qgroup_free
)
6091 btrfs_delalloc_release_metadata(BTRFS_I(inode
), len
, qgroup_free
);
6092 btrfs_free_reserved_data_space(inode
, reserved
, start
, len
);
6095 static int update_block_group(struct btrfs_trans_handle
*trans
,
6096 struct btrfs_fs_info
*info
, u64 bytenr
,
6097 u64 num_bytes
, int alloc
)
6099 struct btrfs_block_group_cache
*cache
= NULL
;
6100 u64 total
= num_bytes
;
6105 /* block accounting for super block */
6106 spin_lock(&info
->delalloc_root_lock
);
6107 old_val
= btrfs_super_bytes_used(info
->super_copy
);
6109 old_val
+= num_bytes
;
6111 old_val
-= num_bytes
;
6112 btrfs_set_super_bytes_used(info
->super_copy
, old_val
);
6113 spin_unlock(&info
->delalloc_root_lock
);
6116 cache
= btrfs_lookup_block_group(info
, bytenr
);
6119 factor
= btrfs_bg_type_to_factor(cache
->flags
);
6122 * If this block group has free space cache written out, we
6123 * need to make sure to load it if we are removing space. This
6124 * is because we need the unpinning stage to actually add the
6125 * space back to the block group, otherwise we will leak space.
6127 if (!alloc
&& cache
->cached
== BTRFS_CACHE_NO
)
6128 cache_block_group(cache
, 1);
6130 byte_in_group
= bytenr
- cache
->key
.objectid
;
6131 WARN_ON(byte_in_group
> cache
->key
.offset
);
6133 spin_lock(&cache
->space_info
->lock
);
6134 spin_lock(&cache
->lock
);
6136 if (btrfs_test_opt(info
, SPACE_CACHE
) &&
6137 cache
->disk_cache_state
< BTRFS_DC_CLEAR
)
6138 cache
->disk_cache_state
= BTRFS_DC_CLEAR
;
6140 old_val
= btrfs_block_group_used(&cache
->item
);
6141 num_bytes
= min(total
, cache
->key
.offset
- byte_in_group
);
6143 old_val
+= num_bytes
;
6144 btrfs_set_block_group_used(&cache
->item
, old_val
);
6145 cache
->reserved
-= num_bytes
;
6146 cache
->space_info
->bytes_reserved
-= num_bytes
;
6147 cache
->space_info
->bytes_used
+= num_bytes
;
6148 cache
->space_info
->disk_used
+= num_bytes
* factor
;
6149 spin_unlock(&cache
->lock
);
6150 spin_unlock(&cache
->space_info
->lock
);
6152 old_val
-= num_bytes
;
6153 btrfs_set_block_group_used(&cache
->item
, old_val
);
6154 cache
->pinned
+= num_bytes
;
6155 cache
->space_info
->bytes_pinned
+= num_bytes
;
6156 cache
->space_info
->bytes_used
-= num_bytes
;
6157 cache
->space_info
->disk_used
-= num_bytes
* factor
;
6158 spin_unlock(&cache
->lock
);
6159 spin_unlock(&cache
->space_info
->lock
);
6161 trace_btrfs_space_reservation(info
, "pinned",
6162 cache
->space_info
->flags
,
6164 percpu_counter_add_batch(&cache
->space_info
->total_bytes_pinned
,
6166 BTRFS_TOTAL_BYTES_PINNED_BATCH
);
6167 set_extent_dirty(info
->pinned_extents
,
6168 bytenr
, bytenr
+ num_bytes
- 1,
6169 GFP_NOFS
| __GFP_NOFAIL
);
6172 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
6173 if (list_empty(&cache
->dirty_list
)) {
6174 list_add_tail(&cache
->dirty_list
,
6175 &trans
->transaction
->dirty_bgs
);
6176 trans
->transaction
->num_dirty_bgs
++;
6177 btrfs_get_block_group(cache
);
6179 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
6182 * No longer have used bytes in this block group, queue it for
6183 * deletion. We do this after adding the block group to the
6184 * dirty list to avoid races between cleaner kthread and space
6187 if (!alloc
&& old_val
== 0)
6188 btrfs_mark_bg_unused(cache
);
6190 btrfs_put_block_group(cache
);
6192 bytenr
+= num_bytes
;
6197 static u64
first_logical_byte(struct btrfs_fs_info
*fs_info
, u64 search_start
)
6199 struct btrfs_block_group_cache
*cache
;
6202 spin_lock(&fs_info
->block_group_cache_lock
);
6203 bytenr
= fs_info
->first_logical_byte
;
6204 spin_unlock(&fs_info
->block_group_cache_lock
);
6206 if (bytenr
< (u64
)-1)
6209 cache
= btrfs_lookup_first_block_group(fs_info
, search_start
);
6213 bytenr
= cache
->key
.objectid
;
6214 btrfs_put_block_group(cache
);
6219 static int pin_down_extent(struct btrfs_fs_info
*fs_info
,
6220 struct btrfs_block_group_cache
*cache
,
6221 u64 bytenr
, u64 num_bytes
, int reserved
)
6223 spin_lock(&cache
->space_info
->lock
);
6224 spin_lock(&cache
->lock
);
6225 cache
->pinned
+= num_bytes
;
6226 cache
->space_info
->bytes_pinned
+= num_bytes
;
6228 cache
->reserved
-= num_bytes
;
6229 cache
->space_info
->bytes_reserved
-= num_bytes
;
6231 spin_unlock(&cache
->lock
);
6232 spin_unlock(&cache
->space_info
->lock
);
6234 trace_btrfs_space_reservation(fs_info
, "pinned",
6235 cache
->space_info
->flags
, num_bytes
, 1);
6236 percpu_counter_add_batch(&cache
->space_info
->total_bytes_pinned
,
6237 num_bytes
, BTRFS_TOTAL_BYTES_PINNED_BATCH
);
6238 set_extent_dirty(fs_info
->pinned_extents
, bytenr
,
6239 bytenr
+ num_bytes
- 1, GFP_NOFS
| __GFP_NOFAIL
);
6244 * this function must be called within transaction
6246 int btrfs_pin_extent(struct btrfs_fs_info
*fs_info
,
6247 u64 bytenr
, u64 num_bytes
, int reserved
)
6249 struct btrfs_block_group_cache
*cache
;
6251 cache
= btrfs_lookup_block_group(fs_info
, bytenr
);
6252 BUG_ON(!cache
); /* Logic error */
6254 pin_down_extent(fs_info
, cache
, bytenr
, num_bytes
, reserved
);
6256 btrfs_put_block_group(cache
);
6261 * this function must be called within transaction
6263 int btrfs_pin_extent_for_log_replay(struct btrfs_fs_info
*fs_info
,
6264 u64 bytenr
, u64 num_bytes
)
6266 struct btrfs_block_group_cache
*cache
;
6269 cache
= btrfs_lookup_block_group(fs_info
, bytenr
);
6274 * pull in the free space cache (if any) so that our pin
6275 * removes the free space from the cache. We have load_only set
6276 * to one because the slow code to read in the free extents does check
6277 * the pinned extents.
6279 cache_block_group(cache
, 1);
6281 pin_down_extent(fs_info
, cache
, bytenr
, num_bytes
, 0);
6283 /* remove us from the free space cache (if we're there at all) */
6284 ret
= btrfs_remove_free_space(cache
, bytenr
, num_bytes
);
6285 btrfs_put_block_group(cache
);
6289 static int __exclude_logged_extent(struct btrfs_fs_info
*fs_info
,
6290 u64 start
, u64 num_bytes
)
6293 struct btrfs_block_group_cache
*block_group
;
6294 struct btrfs_caching_control
*caching_ctl
;
6296 block_group
= btrfs_lookup_block_group(fs_info
, start
);
6300 cache_block_group(block_group
, 0);
6301 caching_ctl
= get_caching_control(block_group
);
6305 BUG_ON(!block_group_cache_done(block_group
));
6306 ret
= btrfs_remove_free_space(block_group
, start
, num_bytes
);
6308 mutex_lock(&caching_ctl
->mutex
);
6310 if (start
>= caching_ctl
->progress
) {
6311 ret
= add_excluded_extent(fs_info
, start
, num_bytes
);
6312 } else if (start
+ num_bytes
<= caching_ctl
->progress
) {
6313 ret
= btrfs_remove_free_space(block_group
,
6316 num_bytes
= caching_ctl
->progress
- start
;
6317 ret
= btrfs_remove_free_space(block_group
,
6322 num_bytes
= (start
+ num_bytes
) -
6323 caching_ctl
->progress
;
6324 start
= caching_ctl
->progress
;
6325 ret
= add_excluded_extent(fs_info
, start
, num_bytes
);
6328 mutex_unlock(&caching_ctl
->mutex
);
6329 put_caching_control(caching_ctl
);
6331 btrfs_put_block_group(block_group
);
6335 int btrfs_exclude_logged_extents(struct btrfs_fs_info
*fs_info
,
6336 struct extent_buffer
*eb
)
6338 struct btrfs_file_extent_item
*item
;
6339 struct btrfs_key key
;
6344 if (!btrfs_fs_incompat(fs_info
, MIXED_GROUPS
))
6347 for (i
= 0; i
< btrfs_header_nritems(eb
); i
++) {
6348 btrfs_item_key_to_cpu(eb
, &key
, i
);
6349 if (key
.type
!= BTRFS_EXTENT_DATA_KEY
)
6351 item
= btrfs_item_ptr(eb
, i
, struct btrfs_file_extent_item
);
6352 found_type
= btrfs_file_extent_type(eb
, item
);
6353 if (found_type
== BTRFS_FILE_EXTENT_INLINE
)
6355 if (btrfs_file_extent_disk_bytenr(eb
, item
) == 0)
6357 key
.objectid
= btrfs_file_extent_disk_bytenr(eb
, item
);
6358 key
.offset
= btrfs_file_extent_disk_num_bytes(eb
, item
);
6359 ret
= __exclude_logged_extent(fs_info
, key
.objectid
, key
.offset
);
6368 btrfs_inc_block_group_reservations(struct btrfs_block_group_cache
*bg
)
6370 atomic_inc(&bg
->reservations
);
6373 void btrfs_dec_block_group_reservations(struct btrfs_fs_info
*fs_info
,
6376 struct btrfs_block_group_cache
*bg
;
6378 bg
= btrfs_lookup_block_group(fs_info
, start
);
6380 if (atomic_dec_and_test(&bg
->reservations
))
6381 wake_up_var(&bg
->reservations
);
6382 btrfs_put_block_group(bg
);
6385 void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache
*bg
)
6387 struct btrfs_space_info
*space_info
= bg
->space_info
;
6391 if (!(bg
->flags
& BTRFS_BLOCK_GROUP_DATA
))
6395 * Our block group is read only but before we set it to read only,
6396 * some task might have had allocated an extent from it already, but it
6397 * has not yet created a respective ordered extent (and added it to a
6398 * root's list of ordered extents).
6399 * Therefore wait for any task currently allocating extents, since the
6400 * block group's reservations counter is incremented while a read lock
6401 * on the groups' semaphore is held and decremented after releasing
6402 * the read access on that semaphore and creating the ordered extent.
6404 down_write(&space_info
->groups_sem
);
6405 up_write(&space_info
->groups_sem
);
6407 wait_var_event(&bg
->reservations
, !atomic_read(&bg
->reservations
));
6411 * btrfs_add_reserved_bytes - update the block_group and space info counters
6412 * @cache: The cache we are manipulating
6413 * @ram_bytes: The number of bytes of file content, and will be same to
6414 * @num_bytes except for the compress path.
6415 * @num_bytes: The number of bytes in question
6416 * @delalloc: The blocks are allocated for the delalloc write
6418 * This is called by the allocator when it reserves space. If this is a
6419 * reservation and the block group has become read only we cannot make the
6420 * reservation and return -EAGAIN, otherwise this function always succeeds.
6422 static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache
*cache
,
6423 u64 ram_bytes
, u64 num_bytes
, int delalloc
)
6425 struct btrfs_space_info
*space_info
= cache
->space_info
;
6428 spin_lock(&space_info
->lock
);
6429 spin_lock(&cache
->lock
);
6433 cache
->reserved
+= num_bytes
;
6434 space_info
->bytes_reserved
+= num_bytes
;
6435 space_info
->bytes_may_use
-= ram_bytes
;
6437 cache
->delalloc_bytes
+= num_bytes
;
6439 spin_unlock(&cache
->lock
);
6440 spin_unlock(&space_info
->lock
);
6445 * btrfs_free_reserved_bytes - update the block_group and space info counters
6446 * @cache: The cache we are manipulating
6447 * @num_bytes: The number of bytes in question
6448 * @delalloc: The blocks are allocated for the delalloc write
6450 * This is called by somebody who is freeing space that was never actually used
6451 * on disk. For example if you reserve some space for a new leaf in transaction
6452 * A and before transaction A commits you free that leaf, you call this with
6453 * reserve set to 0 in order to clear the reservation.
6456 static void btrfs_free_reserved_bytes(struct btrfs_block_group_cache
*cache
,
6457 u64 num_bytes
, int delalloc
)
6459 struct btrfs_space_info
*space_info
= cache
->space_info
;
6461 spin_lock(&space_info
->lock
);
6462 spin_lock(&cache
->lock
);
6464 space_info
->bytes_readonly
+= num_bytes
;
6465 cache
->reserved
-= num_bytes
;
6466 space_info
->bytes_reserved
-= num_bytes
;
6469 cache
->delalloc_bytes
-= num_bytes
;
6470 spin_unlock(&cache
->lock
);
6471 spin_unlock(&space_info
->lock
);
6473 void btrfs_prepare_extent_commit(struct btrfs_fs_info
*fs_info
)
6475 struct btrfs_caching_control
*next
;
6476 struct btrfs_caching_control
*caching_ctl
;
6477 struct btrfs_block_group_cache
*cache
;
6479 down_write(&fs_info
->commit_root_sem
);
6481 list_for_each_entry_safe(caching_ctl
, next
,
6482 &fs_info
->caching_block_groups
, list
) {
6483 cache
= caching_ctl
->block_group
;
6484 if (block_group_cache_done(cache
)) {
6485 cache
->last_byte_to_unpin
= (u64
)-1;
6486 list_del_init(&caching_ctl
->list
);
6487 put_caching_control(caching_ctl
);
6489 cache
->last_byte_to_unpin
= caching_ctl
->progress
;
6493 if (fs_info
->pinned_extents
== &fs_info
->freed_extents
[0])
6494 fs_info
->pinned_extents
= &fs_info
->freed_extents
[1];
6496 fs_info
->pinned_extents
= &fs_info
->freed_extents
[0];
6498 up_write(&fs_info
->commit_root_sem
);
6500 update_global_block_rsv(fs_info
);
6504 * Returns the free cluster for the given space info and sets empty_cluster to
6505 * what it should be based on the mount options.
6507 static struct btrfs_free_cluster
*
6508 fetch_cluster_info(struct btrfs_fs_info
*fs_info
,
6509 struct btrfs_space_info
*space_info
, u64
*empty_cluster
)
6511 struct btrfs_free_cluster
*ret
= NULL
;
6514 if (btrfs_mixed_space_info(space_info
))
6517 if (space_info
->flags
& BTRFS_BLOCK_GROUP_METADATA
) {
6518 ret
= &fs_info
->meta_alloc_cluster
;
6519 if (btrfs_test_opt(fs_info
, SSD
))
6520 *empty_cluster
= SZ_2M
;
6522 *empty_cluster
= SZ_64K
;
6523 } else if ((space_info
->flags
& BTRFS_BLOCK_GROUP_DATA
) &&
6524 btrfs_test_opt(fs_info
, SSD_SPREAD
)) {
6525 *empty_cluster
= SZ_2M
;
6526 ret
= &fs_info
->data_alloc_cluster
;
6532 static int unpin_extent_range(struct btrfs_fs_info
*fs_info
,
6534 const bool return_free_space
)
6536 struct btrfs_block_group_cache
*cache
= NULL
;
6537 struct btrfs_space_info
*space_info
;
6538 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
6539 struct btrfs_free_cluster
*cluster
= NULL
;
6541 u64 total_unpinned
= 0;
6542 u64 empty_cluster
= 0;
6545 while (start
<= end
) {
6548 start
>= cache
->key
.objectid
+ cache
->key
.offset
) {
6550 btrfs_put_block_group(cache
);
6552 cache
= btrfs_lookup_block_group(fs_info
, start
);
6553 BUG_ON(!cache
); /* Logic error */
6555 cluster
= fetch_cluster_info(fs_info
,
6558 empty_cluster
<<= 1;
6561 len
= cache
->key
.objectid
+ cache
->key
.offset
- start
;
6562 len
= min(len
, end
+ 1 - start
);
6564 if (start
< cache
->last_byte_to_unpin
) {
6565 len
= min(len
, cache
->last_byte_to_unpin
- start
);
6566 if (return_free_space
)
6567 btrfs_add_free_space(cache
, start
, len
);
6571 total_unpinned
+= len
;
6572 space_info
= cache
->space_info
;
6575 * If this space cluster has been marked as fragmented and we've
6576 * unpinned enough in this block group to potentially allow a
6577 * cluster to be created inside of it go ahead and clear the
6580 if (cluster
&& cluster
->fragmented
&&
6581 total_unpinned
> empty_cluster
) {
6582 spin_lock(&cluster
->lock
);
6583 cluster
->fragmented
= 0;
6584 spin_unlock(&cluster
->lock
);
6587 spin_lock(&space_info
->lock
);
6588 spin_lock(&cache
->lock
);
6589 cache
->pinned
-= len
;
6590 space_info
->bytes_pinned
-= len
;
6592 trace_btrfs_space_reservation(fs_info
, "pinned",
6593 space_info
->flags
, len
, 0);
6594 space_info
->max_extent_size
= 0;
6595 percpu_counter_add_batch(&space_info
->total_bytes_pinned
,
6596 -len
, BTRFS_TOTAL_BYTES_PINNED_BATCH
);
6598 space_info
->bytes_readonly
+= len
;
6601 spin_unlock(&cache
->lock
);
6602 if (!readonly
&& return_free_space
&&
6603 global_rsv
->space_info
== space_info
) {
6606 spin_lock(&global_rsv
->lock
);
6607 if (!global_rsv
->full
) {
6608 to_add
= min(len
, global_rsv
->size
-
6609 global_rsv
->reserved
);
6610 global_rsv
->reserved
+= to_add
;
6611 space_info
->bytes_may_use
+= to_add
;
6612 if (global_rsv
->reserved
>= global_rsv
->size
)
6613 global_rsv
->full
= 1;
6614 trace_btrfs_space_reservation(fs_info
,
6620 spin_unlock(&global_rsv
->lock
);
6621 /* Add to any tickets we may have */
6623 space_info_add_new_bytes(fs_info
, space_info
,
6626 spin_unlock(&space_info
->lock
);
6630 btrfs_put_block_group(cache
);
6634 int btrfs_finish_extent_commit(struct btrfs_trans_handle
*trans
)
6636 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
6637 struct btrfs_block_group_cache
*block_group
, *tmp
;
6638 struct list_head
*deleted_bgs
;
6639 struct extent_io_tree
*unpin
;
6644 if (fs_info
->pinned_extents
== &fs_info
->freed_extents
[0])
6645 unpin
= &fs_info
->freed_extents
[1];
6647 unpin
= &fs_info
->freed_extents
[0];
6649 while (!trans
->aborted
) {
6650 mutex_lock(&fs_info
->unused_bg_unpin_mutex
);
6651 ret
= find_first_extent_bit(unpin
, 0, &start
, &end
,
6652 EXTENT_DIRTY
, NULL
);
6654 mutex_unlock(&fs_info
->unused_bg_unpin_mutex
);
6658 if (btrfs_test_opt(fs_info
, DISCARD
))
6659 ret
= btrfs_discard_extent(fs_info
, start
,
6660 end
+ 1 - start
, NULL
);
6662 clear_extent_dirty(unpin
, start
, end
);
6663 unpin_extent_range(fs_info
, start
, end
, true);
6664 mutex_unlock(&fs_info
->unused_bg_unpin_mutex
);
6669 * Transaction is finished. We don't need the lock anymore. We
6670 * do need to clean up the block groups in case of a transaction
6673 deleted_bgs
= &trans
->transaction
->deleted_bgs
;
6674 list_for_each_entry_safe(block_group
, tmp
, deleted_bgs
, bg_list
) {
6678 if (!trans
->aborted
)
6679 ret
= btrfs_discard_extent(fs_info
,
6680 block_group
->key
.objectid
,
6681 block_group
->key
.offset
,
6684 list_del_init(&block_group
->bg_list
);
6685 btrfs_put_block_group_trimming(block_group
);
6686 btrfs_put_block_group(block_group
);
6689 const char *errstr
= btrfs_decode_error(ret
);
6691 "discard failed while removing blockgroup: errno=%d %s",
6699 static int __btrfs_free_extent(struct btrfs_trans_handle
*trans
,
6700 struct btrfs_delayed_ref_node
*node
, u64 parent
,
6701 u64 root_objectid
, u64 owner_objectid
,
6702 u64 owner_offset
, int refs_to_drop
,
6703 struct btrfs_delayed_extent_op
*extent_op
)
6705 struct btrfs_fs_info
*info
= trans
->fs_info
;
6706 struct btrfs_key key
;
6707 struct btrfs_path
*path
;
6708 struct btrfs_root
*extent_root
= info
->extent_root
;
6709 struct extent_buffer
*leaf
;
6710 struct btrfs_extent_item
*ei
;
6711 struct btrfs_extent_inline_ref
*iref
;
6714 int extent_slot
= 0;
6715 int found_extent
= 0;
6719 u64 bytenr
= node
->bytenr
;
6720 u64 num_bytes
= node
->num_bytes
;
6722 bool skinny_metadata
= btrfs_fs_incompat(info
, SKINNY_METADATA
);
6724 path
= btrfs_alloc_path();
6728 path
->reada
= READA_FORWARD
;
6729 path
->leave_spinning
= 1;
6731 is_data
= owner_objectid
>= BTRFS_FIRST_FREE_OBJECTID
;
6732 BUG_ON(!is_data
&& refs_to_drop
!= 1);
6735 skinny_metadata
= false;
6737 ret
= lookup_extent_backref(trans
, path
, &iref
, bytenr
, num_bytes
,
6738 parent
, root_objectid
, owner_objectid
,
6741 extent_slot
= path
->slots
[0];
6742 while (extent_slot
>= 0) {
6743 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
6745 if (key
.objectid
!= bytenr
)
6747 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
6748 key
.offset
== num_bytes
) {
6752 if (key
.type
== BTRFS_METADATA_ITEM_KEY
&&
6753 key
.offset
== owner_objectid
) {
6757 if (path
->slots
[0] - extent_slot
> 5)
6762 if (!found_extent
) {
6764 ret
= remove_extent_backref(trans
, path
, NULL
,
6766 is_data
, &last_ref
);
6768 btrfs_abort_transaction(trans
, ret
);
6771 btrfs_release_path(path
);
6772 path
->leave_spinning
= 1;
6774 key
.objectid
= bytenr
;
6775 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
6776 key
.offset
= num_bytes
;
6778 if (!is_data
&& skinny_metadata
) {
6779 key
.type
= BTRFS_METADATA_ITEM_KEY
;
6780 key
.offset
= owner_objectid
;
6783 ret
= btrfs_search_slot(trans
, extent_root
,
6785 if (ret
> 0 && skinny_metadata
&& path
->slots
[0]) {
6787 * Couldn't find our skinny metadata item,
6788 * see if we have ye olde extent item.
6791 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
6793 if (key
.objectid
== bytenr
&&
6794 key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
6795 key
.offset
== num_bytes
)
6799 if (ret
> 0 && skinny_metadata
) {
6800 skinny_metadata
= false;
6801 key
.objectid
= bytenr
;
6802 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
6803 key
.offset
= num_bytes
;
6804 btrfs_release_path(path
);
6805 ret
= btrfs_search_slot(trans
, extent_root
,
6811 "umm, got %d back from search, was looking for %llu",
6814 btrfs_print_leaf(path
->nodes
[0]);
6817 btrfs_abort_transaction(trans
, ret
);
6820 extent_slot
= path
->slots
[0];
6822 } else if (WARN_ON(ret
== -ENOENT
)) {
6823 btrfs_print_leaf(path
->nodes
[0]);
6825 "unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu",
6826 bytenr
, parent
, root_objectid
, owner_objectid
,
6828 btrfs_abort_transaction(trans
, ret
);
6831 btrfs_abort_transaction(trans
, ret
);
6835 leaf
= path
->nodes
[0];
6836 item_size
= btrfs_item_size_nr(leaf
, extent_slot
);
6837 if (unlikely(item_size
< sizeof(*ei
))) {
6839 btrfs_print_v0_err(info
);
6840 btrfs_abort_transaction(trans
, ret
);
6843 ei
= btrfs_item_ptr(leaf
, extent_slot
,
6844 struct btrfs_extent_item
);
6845 if (owner_objectid
< BTRFS_FIRST_FREE_OBJECTID
&&
6846 key
.type
== BTRFS_EXTENT_ITEM_KEY
) {
6847 struct btrfs_tree_block_info
*bi
;
6848 BUG_ON(item_size
< sizeof(*ei
) + sizeof(*bi
));
6849 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
6850 WARN_ON(owner_objectid
!= btrfs_tree_block_level(leaf
, bi
));
6853 refs
= btrfs_extent_refs(leaf
, ei
);
6854 if (refs
< refs_to_drop
) {
6856 "trying to drop %d refs but we only have %Lu for bytenr %Lu",
6857 refs_to_drop
, refs
, bytenr
);
6859 btrfs_abort_transaction(trans
, ret
);
6862 refs
-= refs_to_drop
;
6866 __run_delayed_extent_op(extent_op
, leaf
, ei
);
6868 * In the case of inline back ref, reference count will
6869 * be updated by remove_extent_backref
6872 BUG_ON(!found_extent
);
6874 btrfs_set_extent_refs(leaf
, ei
, refs
);
6875 btrfs_mark_buffer_dirty(leaf
);
6878 ret
= remove_extent_backref(trans
, path
, iref
,
6879 refs_to_drop
, is_data
,
6882 btrfs_abort_transaction(trans
, ret
);
6888 BUG_ON(is_data
&& refs_to_drop
!=
6889 extent_data_ref_count(path
, iref
));
6891 BUG_ON(path
->slots
[0] != extent_slot
);
6893 BUG_ON(path
->slots
[0] != extent_slot
+ 1);
6894 path
->slots
[0] = extent_slot
;
6900 ret
= btrfs_del_items(trans
, extent_root
, path
, path
->slots
[0],
6903 btrfs_abort_transaction(trans
, ret
);
6906 btrfs_release_path(path
);
6909 ret
= btrfs_del_csums(trans
, info
, bytenr
, num_bytes
);
6911 btrfs_abort_transaction(trans
, ret
);
6916 ret
= add_to_free_space_tree(trans
, bytenr
, num_bytes
);
6918 btrfs_abort_transaction(trans
, ret
);
6922 ret
= update_block_group(trans
, info
, bytenr
, num_bytes
, 0);
6924 btrfs_abort_transaction(trans
, ret
);
6928 btrfs_release_path(path
);
6931 btrfs_free_path(path
);
6936 * when we free an block, it is possible (and likely) that we free the last
6937 * delayed ref for that extent as well. This searches the delayed ref tree for
6938 * a given extent, and if there are no other delayed refs to be processed, it
6939 * removes it from the tree.
6941 static noinline
int check_ref_cleanup(struct btrfs_trans_handle
*trans
,
6944 struct btrfs_delayed_ref_head
*head
;
6945 struct btrfs_delayed_ref_root
*delayed_refs
;
6948 delayed_refs
= &trans
->transaction
->delayed_refs
;
6949 spin_lock(&delayed_refs
->lock
);
6950 head
= btrfs_find_delayed_ref_head(delayed_refs
, bytenr
);
6952 goto out_delayed_unlock
;
6954 spin_lock(&head
->lock
);
6955 if (!RB_EMPTY_ROOT(&head
->ref_tree
.rb_root
))
6958 if (head
->extent_op
) {
6959 if (!head
->must_insert_reserved
)
6961 btrfs_free_delayed_extent_op(head
->extent_op
);
6962 head
->extent_op
= NULL
;
6966 * waiting for the lock here would deadlock. If someone else has it
6967 * locked they are already in the process of dropping it anyway
6969 if (!mutex_trylock(&head
->mutex
))
6973 * at this point we have a head with no other entries. Go
6974 * ahead and process it.
6976 rb_erase_cached(&head
->href_node
, &delayed_refs
->href_root
);
6977 RB_CLEAR_NODE(&head
->href_node
);
6978 atomic_dec(&delayed_refs
->num_entries
);
6981 * we don't take a ref on the node because we're removing it from the
6982 * tree, so we just steal the ref the tree was holding.
6984 delayed_refs
->num_heads
--;
6985 if (head
->processing
== 0)
6986 delayed_refs
->num_heads_ready
--;
6987 head
->processing
= 0;
6988 spin_unlock(&head
->lock
);
6989 spin_unlock(&delayed_refs
->lock
);
6991 BUG_ON(head
->extent_op
);
6992 if (head
->must_insert_reserved
)
6995 mutex_unlock(&head
->mutex
);
6996 btrfs_put_delayed_ref_head(head
);
6999 spin_unlock(&head
->lock
);
7002 spin_unlock(&delayed_refs
->lock
);
7006 void btrfs_free_tree_block(struct btrfs_trans_handle
*trans
,
7007 struct btrfs_root
*root
,
7008 struct extent_buffer
*buf
,
7009 u64 parent
, int last_ref
)
7011 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
7015 if (root
->root_key
.objectid
!= BTRFS_TREE_LOG_OBJECTID
) {
7016 int old_ref_mod
, new_ref_mod
;
7018 btrfs_ref_tree_mod(root
, buf
->start
, buf
->len
, parent
,
7019 root
->root_key
.objectid
,
7020 btrfs_header_level(buf
), 0,
7021 BTRFS_DROP_DELAYED_REF
);
7022 ret
= btrfs_add_delayed_tree_ref(trans
, buf
->start
,
7024 root
->root_key
.objectid
,
7025 btrfs_header_level(buf
),
7026 BTRFS_DROP_DELAYED_REF
, NULL
,
7027 &old_ref_mod
, &new_ref_mod
);
7028 BUG_ON(ret
); /* -ENOMEM */
7029 pin
= old_ref_mod
>= 0 && new_ref_mod
< 0;
7032 if (last_ref
&& btrfs_header_generation(buf
) == trans
->transid
) {
7033 struct btrfs_block_group_cache
*cache
;
7035 if (root
->root_key
.objectid
!= BTRFS_TREE_LOG_OBJECTID
) {
7036 ret
= check_ref_cleanup(trans
, buf
->start
);
7042 cache
= btrfs_lookup_block_group(fs_info
, buf
->start
);
7044 if (btrfs_header_flag(buf
, BTRFS_HEADER_FLAG_WRITTEN
)) {
7045 pin_down_extent(fs_info
, cache
, buf
->start
,
7047 btrfs_put_block_group(cache
);
7051 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY
, &buf
->bflags
));
7053 btrfs_add_free_space(cache
, buf
->start
, buf
->len
);
7054 btrfs_free_reserved_bytes(cache
, buf
->len
, 0);
7055 btrfs_put_block_group(cache
);
7056 trace_btrfs_reserved_extent_free(fs_info
, buf
->start
, buf
->len
);
7060 add_pinned_bytes(fs_info
, buf
->len
, true,
7061 root
->root_key
.objectid
);
7065 * Deleting the buffer, clear the corrupt flag since it doesn't
7068 clear_bit(EXTENT_BUFFER_CORRUPT
, &buf
->bflags
);
7072 /* Can return -ENOMEM */
7073 int btrfs_free_extent(struct btrfs_trans_handle
*trans
,
7074 struct btrfs_root
*root
,
7075 u64 bytenr
, u64 num_bytes
, u64 parent
, u64 root_objectid
,
7076 u64 owner
, u64 offset
)
7078 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
7079 int old_ref_mod
, new_ref_mod
;
7082 if (btrfs_is_testing(fs_info
))
7085 if (root_objectid
!= BTRFS_TREE_LOG_OBJECTID
)
7086 btrfs_ref_tree_mod(root
, bytenr
, num_bytes
, parent
,
7087 root_objectid
, owner
, offset
,
7088 BTRFS_DROP_DELAYED_REF
);
7091 * tree log blocks never actually go into the extent allocation
7092 * tree, just update pinning info and exit early.
7094 if (root_objectid
== BTRFS_TREE_LOG_OBJECTID
) {
7095 WARN_ON(owner
>= BTRFS_FIRST_FREE_OBJECTID
);
7096 /* unlocks the pinned mutex */
7097 btrfs_pin_extent(fs_info
, bytenr
, num_bytes
, 1);
7098 old_ref_mod
= new_ref_mod
= 0;
7100 } else if (owner
< BTRFS_FIRST_FREE_OBJECTID
) {
7101 ret
= btrfs_add_delayed_tree_ref(trans
, bytenr
,
7103 root_objectid
, (int)owner
,
7104 BTRFS_DROP_DELAYED_REF
, NULL
,
7105 &old_ref_mod
, &new_ref_mod
);
7107 ret
= btrfs_add_delayed_data_ref(trans
, bytenr
,
7109 root_objectid
, owner
, offset
,
7110 0, BTRFS_DROP_DELAYED_REF
,
7111 &old_ref_mod
, &new_ref_mod
);
7114 if (ret
== 0 && old_ref_mod
>= 0 && new_ref_mod
< 0) {
7115 bool metadata
= owner
< BTRFS_FIRST_FREE_OBJECTID
;
7117 add_pinned_bytes(fs_info
, num_bytes
, metadata
, root_objectid
);
7124 * when we wait for progress in the block group caching, its because
7125 * our allocation attempt failed at least once. So, we must sleep
7126 * and let some progress happen before we try again.
7128 * This function will sleep at least once waiting for new free space to
7129 * show up, and then it will check the block group free space numbers
7130 * for our min num_bytes. Another option is to have it go ahead
7131 * and look in the rbtree for a free extent of a given size, but this
7134 * Callers of this must check if cache->cached == BTRFS_CACHE_ERROR before using
7135 * any of the information in this block group.
7137 static noinline
void
7138 wait_block_group_cache_progress(struct btrfs_block_group_cache
*cache
,
7141 struct btrfs_caching_control
*caching_ctl
;
7143 caching_ctl
= get_caching_control(cache
);
7147 wait_event(caching_ctl
->wait
, block_group_cache_done(cache
) ||
7148 (cache
->free_space_ctl
->free_space
>= num_bytes
));
7150 put_caching_control(caching_ctl
);
7154 wait_block_group_cache_done(struct btrfs_block_group_cache
*cache
)
7156 struct btrfs_caching_control
*caching_ctl
;
7159 caching_ctl
= get_caching_control(cache
);
7161 return (cache
->cached
== BTRFS_CACHE_ERROR
) ? -EIO
: 0;
7163 wait_event(caching_ctl
->wait
, block_group_cache_done(cache
));
7164 if (cache
->cached
== BTRFS_CACHE_ERROR
)
7166 put_caching_control(caching_ctl
);
7170 enum btrfs_loop_type
{
7171 LOOP_CACHING_NOWAIT
= 0,
7172 LOOP_CACHING_WAIT
= 1,
7173 LOOP_ALLOC_CHUNK
= 2,
7174 LOOP_NO_EMPTY_SIZE
= 3,
7178 btrfs_lock_block_group(struct btrfs_block_group_cache
*cache
,
7182 down_read(&cache
->data_rwsem
);
7186 btrfs_grab_block_group(struct btrfs_block_group_cache
*cache
,
7189 btrfs_get_block_group(cache
);
7191 down_read(&cache
->data_rwsem
);
7194 static struct btrfs_block_group_cache
*
7195 btrfs_lock_cluster(struct btrfs_block_group_cache
*block_group
,
7196 struct btrfs_free_cluster
*cluster
,
7199 struct btrfs_block_group_cache
*used_bg
= NULL
;
7201 spin_lock(&cluster
->refill_lock
);
7203 used_bg
= cluster
->block_group
;
7207 if (used_bg
== block_group
)
7210 btrfs_get_block_group(used_bg
);
7215 if (down_read_trylock(&used_bg
->data_rwsem
))
7218 spin_unlock(&cluster
->refill_lock
);
7220 /* We should only have one-level nested. */
7221 down_read_nested(&used_bg
->data_rwsem
, SINGLE_DEPTH_NESTING
);
7223 spin_lock(&cluster
->refill_lock
);
7224 if (used_bg
== cluster
->block_group
)
7227 up_read(&used_bg
->data_rwsem
);
7228 btrfs_put_block_group(used_bg
);
7233 btrfs_release_block_group(struct btrfs_block_group_cache
*cache
,
7237 up_read(&cache
->data_rwsem
);
7238 btrfs_put_block_group(cache
);
7242 * walks the btree of allocated extents and find a hole of a given size.
7243 * The key ins is changed to record the hole:
7244 * ins->objectid == start position
7245 * ins->flags = BTRFS_EXTENT_ITEM_KEY
7246 * ins->offset == the size of the hole.
7247 * Any available blocks before search_start are skipped.
7249 * If there is no suitable free space, we will record the max size of
7250 * the free space extent currently.
7252 static noinline
int find_free_extent(struct btrfs_fs_info
*fs_info
,
7253 u64 ram_bytes
, u64 num_bytes
, u64 empty_size
,
7254 u64 hint_byte
, struct btrfs_key
*ins
,
7255 u64 flags
, int delalloc
)
7258 struct btrfs_root
*root
= fs_info
->extent_root
;
7259 struct btrfs_free_cluster
*last_ptr
= NULL
;
7260 struct btrfs_block_group_cache
*block_group
= NULL
;
7261 u64 search_start
= 0;
7262 u64 max_extent_size
= 0;
7263 u64 empty_cluster
= 0;
7264 struct btrfs_space_info
*space_info
;
7266 int index
= btrfs_bg_flags_to_raid_index(flags
);
7267 bool failed_cluster_refill
= false;
7268 bool failed_alloc
= false;
7269 bool use_cluster
= true;
7270 bool have_caching_bg
= false;
7271 bool orig_have_caching_bg
= false;
7272 bool full_search
= false;
7274 WARN_ON(num_bytes
< fs_info
->sectorsize
);
7275 ins
->type
= BTRFS_EXTENT_ITEM_KEY
;
7279 trace_find_free_extent(fs_info
, num_bytes
, empty_size
, flags
);
7281 space_info
= __find_space_info(fs_info
, flags
);
7283 btrfs_err(fs_info
, "No space info for %llu", flags
);
7288 * If our free space is heavily fragmented we may not be able to make
7289 * big contiguous allocations, so instead of doing the expensive search
7290 * for free space, simply return ENOSPC with our max_extent_size so we
7291 * can go ahead and search for a more manageable chunk.
7293 * If our max_extent_size is large enough for our allocation simply
7294 * disable clustering since we will likely not be able to find enough
7295 * space to create a cluster and induce latency trying.
7297 if (unlikely(space_info
->max_extent_size
)) {
7298 spin_lock(&space_info
->lock
);
7299 if (space_info
->max_extent_size
&&
7300 num_bytes
> space_info
->max_extent_size
) {
7301 ins
->offset
= space_info
->max_extent_size
;
7302 spin_unlock(&space_info
->lock
);
7304 } else if (space_info
->max_extent_size
) {
7305 use_cluster
= false;
7307 spin_unlock(&space_info
->lock
);
7310 last_ptr
= fetch_cluster_info(fs_info
, space_info
, &empty_cluster
);
7312 spin_lock(&last_ptr
->lock
);
7313 if (last_ptr
->block_group
)
7314 hint_byte
= last_ptr
->window_start
;
7315 if (last_ptr
->fragmented
) {
7317 * We still set window_start so we can keep track of the
7318 * last place we found an allocation to try and save
7321 hint_byte
= last_ptr
->window_start
;
7322 use_cluster
= false;
7324 spin_unlock(&last_ptr
->lock
);
7327 search_start
= max(search_start
, first_logical_byte(fs_info
, 0));
7328 search_start
= max(search_start
, hint_byte
);
7329 if (search_start
== hint_byte
) {
7330 block_group
= btrfs_lookup_block_group(fs_info
, search_start
);
7332 * we don't want to use the block group if it doesn't match our
7333 * allocation bits, or if its not cached.
7335 * However if we are re-searching with an ideal block group
7336 * picked out then we don't care that the block group is cached.
7338 if (block_group
&& block_group_bits(block_group
, flags
) &&
7339 block_group
->cached
!= BTRFS_CACHE_NO
) {
7340 down_read(&space_info
->groups_sem
);
7341 if (list_empty(&block_group
->list
) ||
7344 * someone is removing this block group,
7345 * we can't jump into the have_block_group
7346 * target because our list pointers are not
7349 btrfs_put_block_group(block_group
);
7350 up_read(&space_info
->groups_sem
);
7352 index
= btrfs_bg_flags_to_raid_index(
7353 block_group
->flags
);
7354 btrfs_lock_block_group(block_group
, delalloc
);
7355 goto have_block_group
;
7357 } else if (block_group
) {
7358 btrfs_put_block_group(block_group
);
7362 have_caching_bg
= false;
7363 if (index
== 0 || index
== btrfs_bg_flags_to_raid_index(flags
))
7365 down_read(&space_info
->groups_sem
);
7366 list_for_each_entry(block_group
, &space_info
->block_groups
[index
],
7371 /* If the block group is read-only, we can skip it entirely. */
7372 if (unlikely(block_group
->ro
))
7375 btrfs_grab_block_group(block_group
, delalloc
);
7376 search_start
= block_group
->key
.objectid
;
7379 * this can happen if we end up cycling through all the
7380 * raid types, but we want to make sure we only allocate
7381 * for the proper type.
7383 if (!block_group_bits(block_group
, flags
)) {
7384 u64 extra
= BTRFS_BLOCK_GROUP_DUP
|
7385 BTRFS_BLOCK_GROUP_RAID1
|
7386 BTRFS_BLOCK_GROUP_RAID5
|
7387 BTRFS_BLOCK_GROUP_RAID6
|
7388 BTRFS_BLOCK_GROUP_RAID10
;
7391 * if they asked for extra copies and this block group
7392 * doesn't provide them, bail. This does allow us to
7393 * fill raid0 from raid1.
7395 if ((flags
& extra
) && !(block_group
->flags
& extra
))
7400 cached
= block_group_cache_done(block_group
);
7401 if (unlikely(!cached
)) {
7402 have_caching_bg
= true;
7403 ret
= cache_block_group(block_group
, 0);
7408 if (unlikely(block_group
->cached
== BTRFS_CACHE_ERROR
))
7412 * Ok we want to try and use the cluster allocator, so
7415 if (last_ptr
&& use_cluster
) {
7416 struct btrfs_block_group_cache
*used_block_group
;
7417 unsigned long aligned_cluster
;
7419 * the refill lock keeps out other
7420 * people trying to start a new cluster
7422 used_block_group
= btrfs_lock_cluster(block_group
,
7425 if (!used_block_group
)
7426 goto refill_cluster
;
7428 if (used_block_group
!= block_group
&&
7429 (used_block_group
->ro
||
7430 !block_group_bits(used_block_group
, flags
)))
7431 goto release_cluster
;
7433 offset
= btrfs_alloc_from_cluster(used_block_group
,
7436 used_block_group
->key
.objectid
,
7439 /* we have a block, we're done */
7440 spin_unlock(&last_ptr
->refill_lock
);
7441 trace_btrfs_reserve_extent_cluster(
7443 search_start
, num_bytes
);
7444 if (used_block_group
!= block_group
) {
7445 btrfs_release_block_group(block_group
,
7447 block_group
= used_block_group
;
7452 WARN_ON(last_ptr
->block_group
!= used_block_group
);
7454 /* If we are on LOOP_NO_EMPTY_SIZE, we can't
7455 * set up a new clusters, so lets just skip it
7456 * and let the allocator find whatever block
7457 * it can find. If we reach this point, we
7458 * will have tried the cluster allocator
7459 * plenty of times and not have found
7460 * anything, so we are likely way too
7461 * fragmented for the clustering stuff to find
7464 * However, if the cluster is taken from the
7465 * current block group, release the cluster
7466 * first, so that we stand a better chance of
7467 * succeeding in the unclustered
7469 if (loop
>= LOOP_NO_EMPTY_SIZE
&&
7470 used_block_group
!= block_group
) {
7471 spin_unlock(&last_ptr
->refill_lock
);
7472 btrfs_release_block_group(used_block_group
,
7474 goto unclustered_alloc
;
7478 * this cluster didn't work out, free it and
7481 btrfs_return_cluster_to_free_space(NULL
, last_ptr
);
7483 if (used_block_group
!= block_group
)
7484 btrfs_release_block_group(used_block_group
,
7487 if (loop
>= LOOP_NO_EMPTY_SIZE
) {
7488 spin_unlock(&last_ptr
->refill_lock
);
7489 goto unclustered_alloc
;
7492 aligned_cluster
= max_t(unsigned long,
7493 empty_cluster
+ empty_size
,
7494 block_group
->full_stripe_len
);
7496 /* allocate a cluster in this block group */
7497 ret
= btrfs_find_space_cluster(fs_info
, block_group
,
7498 last_ptr
, search_start
,
7503 * now pull our allocation out of this
7506 offset
= btrfs_alloc_from_cluster(block_group
,
7512 /* we found one, proceed */
7513 spin_unlock(&last_ptr
->refill_lock
);
7514 trace_btrfs_reserve_extent_cluster(
7515 block_group
, search_start
,
7519 } else if (!cached
&& loop
> LOOP_CACHING_NOWAIT
7520 && !failed_cluster_refill
) {
7521 spin_unlock(&last_ptr
->refill_lock
);
7523 failed_cluster_refill
= true;
7524 wait_block_group_cache_progress(block_group
,
7525 num_bytes
+ empty_cluster
+ empty_size
);
7526 goto have_block_group
;
7530 * at this point we either didn't find a cluster
7531 * or we weren't able to allocate a block from our
7532 * cluster. Free the cluster we've been trying
7533 * to use, and go to the next block group
7535 btrfs_return_cluster_to_free_space(NULL
, last_ptr
);
7536 spin_unlock(&last_ptr
->refill_lock
);
7542 * We are doing an unclustered alloc, set the fragmented flag so
7543 * we don't bother trying to setup a cluster again until we get
7546 if (unlikely(last_ptr
)) {
7547 spin_lock(&last_ptr
->lock
);
7548 last_ptr
->fragmented
= 1;
7549 spin_unlock(&last_ptr
->lock
);
7552 struct btrfs_free_space_ctl
*ctl
=
7553 block_group
->free_space_ctl
;
7555 spin_lock(&ctl
->tree_lock
);
7556 if (ctl
->free_space
<
7557 num_bytes
+ empty_cluster
+ empty_size
) {
7558 if (ctl
->free_space
> max_extent_size
)
7559 max_extent_size
= ctl
->free_space
;
7560 spin_unlock(&ctl
->tree_lock
);
7563 spin_unlock(&ctl
->tree_lock
);
7566 offset
= btrfs_find_space_for_alloc(block_group
, search_start
,
7567 num_bytes
, empty_size
,
7570 * If we didn't find a chunk, and we haven't failed on this
7571 * block group before, and this block group is in the middle of
7572 * caching and we are ok with waiting, then go ahead and wait
7573 * for progress to be made, and set failed_alloc to true.
7575 * If failed_alloc is true then we've already waited on this
7576 * block group once and should move on to the next block group.
7578 if (!offset
&& !failed_alloc
&& !cached
&&
7579 loop
> LOOP_CACHING_NOWAIT
) {
7580 wait_block_group_cache_progress(block_group
,
7581 num_bytes
+ empty_size
);
7582 failed_alloc
= true;
7583 goto have_block_group
;
7584 } else if (!offset
) {
7588 search_start
= round_up(offset
, fs_info
->stripesize
);
7590 /* move on to the next group */
7591 if (search_start
+ num_bytes
>
7592 block_group
->key
.objectid
+ block_group
->key
.offset
) {
7593 btrfs_add_free_space(block_group
, offset
, num_bytes
);
7597 if (offset
< search_start
)
7598 btrfs_add_free_space(block_group
, offset
,
7599 search_start
- offset
);
7601 ret
= btrfs_add_reserved_bytes(block_group
, ram_bytes
,
7602 num_bytes
, delalloc
);
7603 if (ret
== -EAGAIN
) {
7604 btrfs_add_free_space(block_group
, offset
, num_bytes
);
7607 btrfs_inc_block_group_reservations(block_group
);
7609 /* we are all good, lets return */
7610 ins
->objectid
= search_start
;
7611 ins
->offset
= num_bytes
;
7613 trace_btrfs_reserve_extent(block_group
, search_start
, num_bytes
);
7614 btrfs_release_block_group(block_group
, delalloc
);
7617 failed_cluster_refill
= false;
7618 failed_alloc
= false;
7619 BUG_ON(btrfs_bg_flags_to_raid_index(block_group
->flags
) !=
7621 btrfs_release_block_group(block_group
, delalloc
);
7624 up_read(&space_info
->groups_sem
);
7626 if ((loop
== LOOP_CACHING_NOWAIT
) && have_caching_bg
7627 && !orig_have_caching_bg
)
7628 orig_have_caching_bg
= true;
7630 if (!ins
->objectid
&& loop
>= LOOP_CACHING_WAIT
&& have_caching_bg
)
7633 if (!ins
->objectid
&& ++index
< BTRFS_NR_RAID_TYPES
)
7637 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
7638 * caching kthreads as we move along
7639 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
7640 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
7641 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
7644 if (!ins
->objectid
&& loop
< LOOP_NO_EMPTY_SIZE
) {
7646 if (loop
== LOOP_CACHING_NOWAIT
) {
7648 * We want to skip the LOOP_CACHING_WAIT step if we
7649 * don't have any uncached bgs and we've already done a
7650 * full search through.
7652 if (orig_have_caching_bg
|| !full_search
)
7653 loop
= LOOP_CACHING_WAIT
;
7655 loop
= LOOP_ALLOC_CHUNK
;
7660 if (loop
== LOOP_ALLOC_CHUNK
) {
7661 struct btrfs_trans_handle
*trans
;
7664 trans
= current
->journal_info
;
7668 trans
= btrfs_join_transaction(root
);
7670 if (IS_ERR(trans
)) {
7671 ret
= PTR_ERR(trans
);
7675 ret
= do_chunk_alloc(trans
, flags
, CHUNK_ALLOC_FORCE
);
7678 * If we can't allocate a new chunk we've already looped
7679 * through at least once, move on to the NO_EMPTY_SIZE
7683 loop
= LOOP_NO_EMPTY_SIZE
;
7686 * Do not bail out on ENOSPC since we
7687 * can do more things.
7689 if (ret
< 0 && ret
!= -ENOSPC
)
7690 btrfs_abort_transaction(trans
, ret
);
7694 btrfs_end_transaction(trans
);
7699 if (loop
== LOOP_NO_EMPTY_SIZE
) {
7701 * Don't loop again if we already have no empty_size and
7704 if (empty_size
== 0 &&
7705 empty_cluster
== 0) {
7714 } else if (!ins
->objectid
) {
7716 } else if (ins
->objectid
) {
7717 if (!use_cluster
&& last_ptr
) {
7718 spin_lock(&last_ptr
->lock
);
7719 last_ptr
->window_start
= ins
->objectid
;
7720 spin_unlock(&last_ptr
->lock
);
7725 if (ret
== -ENOSPC
) {
7726 spin_lock(&space_info
->lock
);
7727 space_info
->max_extent_size
= max_extent_size
;
7728 spin_unlock(&space_info
->lock
);
7729 ins
->offset
= max_extent_size
;
7734 static void dump_space_info(struct btrfs_fs_info
*fs_info
,
7735 struct btrfs_space_info
*info
, u64 bytes
,
7736 int dump_block_groups
)
7738 struct btrfs_block_group_cache
*cache
;
7741 spin_lock(&info
->lock
);
7742 btrfs_info(fs_info
, "space_info %llu has %llu free, is %sfull",
7744 info
->total_bytes
- btrfs_space_info_used(info
, true),
7745 info
->full
? "" : "not ");
7747 "space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
7748 info
->total_bytes
, info
->bytes_used
, info
->bytes_pinned
,
7749 info
->bytes_reserved
, info
->bytes_may_use
,
7750 info
->bytes_readonly
);
7751 spin_unlock(&info
->lock
);
7753 if (!dump_block_groups
)
7756 down_read(&info
->groups_sem
);
7758 list_for_each_entry(cache
, &info
->block_groups
[index
], list
) {
7759 spin_lock(&cache
->lock
);
7761 "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
7762 cache
->key
.objectid
, cache
->key
.offset
,
7763 btrfs_block_group_used(&cache
->item
), cache
->pinned
,
7764 cache
->reserved
, cache
->ro
? "[readonly]" : "");
7765 btrfs_dump_free_space(cache
, bytes
);
7766 spin_unlock(&cache
->lock
);
7768 if (++index
< BTRFS_NR_RAID_TYPES
)
7770 up_read(&info
->groups_sem
);
7774 * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
7775 * hole that is at least as big as @num_bytes.
7777 * @root - The root that will contain this extent
7779 * @ram_bytes - The amount of space in ram that @num_bytes take. This
7780 * is used for accounting purposes. This value differs
7781 * from @num_bytes only in the case of compressed extents.
7783 * @num_bytes - Number of bytes to allocate on-disk.
7785 * @min_alloc_size - Indicates the minimum amount of space that the
7786 * allocator should try to satisfy. In some cases
7787 * @num_bytes may be larger than what is required and if
7788 * the filesystem is fragmented then allocation fails.
7789 * However, the presence of @min_alloc_size gives a
7790 * chance to try and satisfy the smaller allocation.
7792 * @empty_size - A hint that you plan on doing more COW. This is the
7793 * size in bytes the allocator should try to find free
7794 * next to the block it returns. This is just a hint and
7795 * may be ignored by the allocator.
7797 * @hint_byte - Hint to the allocator to start searching above the byte
7798 * address passed. It might be ignored.
7800 * @ins - This key is modified to record the found hole. It will
7801 * have the following values:
7802 * ins->objectid == start position
7803 * ins->flags = BTRFS_EXTENT_ITEM_KEY
7804 * ins->offset == the size of the hole.
7806 * @is_data - Boolean flag indicating whether an extent is
7807 * allocated for data (true) or metadata (false)
7809 * @delalloc - Boolean flag indicating whether this allocation is for
7810 * delalloc or not. If 'true' data_rwsem of block groups
7811 * is going to be acquired.
7814 * Returns 0 when an allocation succeeded or < 0 when an error occurred. In
7815 * case -ENOSPC is returned then @ins->offset will contain the size of the
7816 * largest available hole the allocator managed to find.
7818 int btrfs_reserve_extent(struct btrfs_root
*root
, u64 ram_bytes
,
7819 u64 num_bytes
, u64 min_alloc_size
,
7820 u64 empty_size
, u64 hint_byte
,
7821 struct btrfs_key
*ins
, int is_data
, int delalloc
)
7823 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
7824 bool final_tried
= num_bytes
== min_alloc_size
;
7828 flags
= get_alloc_profile_by_root(root
, is_data
);
7830 WARN_ON(num_bytes
< fs_info
->sectorsize
);
7831 ret
= find_free_extent(fs_info
, ram_bytes
, num_bytes
, empty_size
,
7832 hint_byte
, ins
, flags
, delalloc
);
7833 if (!ret
&& !is_data
) {
7834 btrfs_dec_block_group_reservations(fs_info
, ins
->objectid
);
7835 } else if (ret
== -ENOSPC
) {
7836 if (!final_tried
&& ins
->offset
) {
7837 num_bytes
= min(num_bytes
>> 1, ins
->offset
);
7838 num_bytes
= round_down(num_bytes
,
7839 fs_info
->sectorsize
);
7840 num_bytes
= max(num_bytes
, min_alloc_size
);
7841 ram_bytes
= num_bytes
;
7842 if (num_bytes
== min_alloc_size
)
7845 } else if (btrfs_test_opt(fs_info
, ENOSPC_DEBUG
)) {
7846 struct btrfs_space_info
*sinfo
;
7848 sinfo
= __find_space_info(fs_info
, flags
);
7850 "allocation failed flags %llu, wanted %llu",
7853 dump_space_info(fs_info
, sinfo
, num_bytes
, 1);
7860 static int __btrfs_free_reserved_extent(struct btrfs_fs_info
*fs_info
,
7862 int pin
, int delalloc
)
7864 struct btrfs_block_group_cache
*cache
;
7867 cache
= btrfs_lookup_block_group(fs_info
, start
);
7869 btrfs_err(fs_info
, "Unable to find block group for %llu",
7875 pin_down_extent(fs_info
, cache
, start
, len
, 1);
7877 if (btrfs_test_opt(fs_info
, DISCARD
))
7878 ret
= btrfs_discard_extent(fs_info
, start
, len
, NULL
);
7879 btrfs_add_free_space(cache
, start
, len
);
7880 btrfs_free_reserved_bytes(cache
, len
, delalloc
);
7881 trace_btrfs_reserved_extent_free(fs_info
, start
, len
);
7884 btrfs_put_block_group(cache
);
7888 int btrfs_free_reserved_extent(struct btrfs_fs_info
*fs_info
,
7889 u64 start
, u64 len
, int delalloc
)
7891 return __btrfs_free_reserved_extent(fs_info
, start
, len
, 0, delalloc
);
7894 int btrfs_free_and_pin_reserved_extent(struct btrfs_fs_info
*fs_info
,
7897 return __btrfs_free_reserved_extent(fs_info
, start
, len
, 1, 0);
7900 static int alloc_reserved_file_extent(struct btrfs_trans_handle
*trans
,
7901 u64 parent
, u64 root_objectid
,
7902 u64 flags
, u64 owner
, u64 offset
,
7903 struct btrfs_key
*ins
, int ref_mod
)
7905 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
7907 struct btrfs_extent_item
*extent_item
;
7908 struct btrfs_extent_inline_ref
*iref
;
7909 struct btrfs_path
*path
;
7910 struct extent_buffer
*leaf
;
7915 type
= BTRFS_SHARED_DATA_REF_KEY
;
7917 type
= BTRFS_EXTENT_DATA_REF_KEY
;
7919 size
= sizeof(*extent_item
) + btrfs_extent_inline_ref_size(type
);
7921 path
= btrfs_alloc_path();
7925 path
->leave_spinning
= 1;
7926 ret
= btrfs_insert_empty_item(trans
, fs_info
->extent_root
, path
,
7929 btrfs_free_path(path
);
7933 leaf
= path
->nodes
[0];
7934 extent_item
= btrfs_item_ptr(leaf
, path
->slots
[0],
7935 struct btrfs_extent_item
);
7936 btrfs_set_extent_refs(leaf
, extent_item
, ref_mod
);
7937 btrfs_set_extent_generation(leaf
, extent_item
, trans
->transid
);
7938 btrfs_set_extent_flags(leaf
, extent_item
,
7939 flags
| BTRFS_EXTENT_FLAG_DATA
);
7941 iref
= (struct btrfs_extent_inline_ref
*)(extent_item
+ 1);
7942 btrfs_set_extent_inline_ref_type(leaf
, iref
, type
);
7944 struct btrfs_shared_data_ref
*ref
;
7945 ref
= (struct btrfs_shared_data_ref
*)(iref
+ 1);
7946 btrfs_set_extent_inline_ref_offset(leaf
, iref
, parent
);
7947 btrfs_set_shared_data_ref_count(leaf
, ref
, ref_mod
);
7949 struct btrfs_extent_data_ref
*ref
;
7950 ref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
7951 btrfs_set_extent_data_ref_root(leaf
, ref
, root_objectid
);
7952 btrfs_set_extent_data_ref_objectid(leaf
, ref
, owner
);
7953 btrfs_set_extent_data_ref_offset(leaf
, ref
, offset
);
7954 btrfs_set_extent_data_ref_count(leaf
, ref
, ref_mod
);
7957 btrfs_mark_buffer_dirty(path
->nodes
[0]);
7958 btrfs_free_path(path
);
7960 ret
= remove_from_free_space_tree(trans
, ins
->objectid
, ins
->offset
);
7964 ret
= update_block_group(trans
, fs_info
, ins
->objectid
, ins
->offset
, 1);
7965 if (ret
) { /* -ENOENT, logic error */
7966 btrfs_err(fs_info
, "update block group failed for %llu %llu",
7967 ins
->objectid
, ins
->offset
);
7970 trace_btrfs_reserved_extent_alloc(fs_info
, ins
->objectid
, ins
->offset
);
7974 static int alloc_reserved_tree_block(struct btrfs_trans_handle
*trans
,
7975 struct btrfs_delayed_ref_node
*node
,
7976 struct btrfs_delayed_extent_op
*extent_op
)
7978 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
7980 struct btrfs_extent_item
*extent_item
;
7981 struct btrfs_key extent_key
;
7982 struct btrfs_tree_block_info
*block_info
;
7983 struct btrfs_extent_inline_ref
*iref
;
7984 struct btrfs_path
*path
;
7985 struct extent_buffer
*leaf
;
7986 struct btrfs_delayed_tree_ref
*ref
;
7987 u32 size
= sizeof(*extent_item
) + sizeof(*iref
);
7989 u64 flags
= extent_op
->flags_to_set
;
7990 bool skinny_metadata
= btrfs_fs_incompat(fs_info
, SKINNY_METADATA
);
7992 ref
= btrfs_delayed_node_to_tree_ref(node
);
7994 extent_key
.objectid
= node
->bytenr
;
7995 if (skinny_metadata
) {
7996 extent_key
.offset
= ref
->level
;
7997 extent_key
.type
= BTRFS_METADATA_ITEM_KEY
;
7998 num_bytes
= fs_info
->nodesize
;
8000 extent_key
.offset
= node
->num_bytes
;
8001 extent_key
.type
= BTRFS_EXTENT_ITEM_KEY
;
8002 size
+= sizeof(*block_info
);
8003 num_bytes
= node
->num_bytes
;
8006 path
= btrfs_alloc_path();
8008 btrfs_free_and_pin_reserved_extent(fs_info
,
8009 extent_key
.objectid
,
8014 path
->leave_spinning
= 1;
8015 ret
= btrfs_insert_empty_item(trans
, fs_info
->extent_root
, path
,
8018 btrfs_free_path(path
);
8019 btrfs_free_and_pin_reserved_extent(fs_info
,
8020 extent_key
.objectid
,
8025 leaf
= path
->nodes
[0];
8026 extent_item
= btrfs_item_ptr(leaf
, path
->slots
[0],
8027 struct btrfs_extent_item
);
8028 btrfs_set_extent_refs(leaf
, extent_item
, 1);
8029 btrfs_set_extent_generation(leaf
, extent_item
, trans
->transid
);
8030 btrfs_set_extent_flags(leaf
, extent_item
,
8031 flags
| BTRFS_EXTENT_FLAG_TREE_BLOCK
);
8033 if (skinny_metadata
) {
8034 iref
= (struct btrfs_extent_inline_ref
*)(extent_item
+ 1);
8036 block_info
= (struct btrfs_tree_block_info
*)(extent_item
+ 1);
8037 btrfs_set_tree_block_key(leaf
, block_info
, &extent_op
->key
);
8038 btrfs_set_tree_block_level(leaf
, block_info
, ref
->level
);
8039 iref
= (struct btrfs_extent_inline_ref
*)(block_info
+ 1);
8042 if (node
->type
== BTRFS_SHARED_BLOCK_REF_KEY
) {
8043 BUG_ON(!(flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
));
8044 btrfs_set_extent_inline_ref_type(leaf
, iref
,
8045 BTRFS_SHARED_BLOCK_REF_KEY
);
8046 btrfs_set_extent_inline_ref_offset(leaf
, iref
, ref
->parent
);
8048 btrfs_set_extent_inline_ref_type(leaf
, iref
,
8049 BTRFS_TREE_BLOCK_REF_KEY
);
8050 btrfs_set_extent_inline_ref_offset(leaf
, iref
, ref
->root
);
8053 btrfs_mark_buffer_dirty(leaf
);
8054 btrfs_free_path(path
);
8056 ret
= remove_from_free_space_tree(trans
, extent_key
.objectid
,
8061 ret
= update_block_group(trans
, fs_info
, extent_key
.objectid
,
8062 fs_info
->nodesize
, 1);
8063 if (ret
) { /* -ENOENT, logic error */
8064 btrfs_err(fs_info
, "update block group failed for %llu %llu",
8065 extent_key
.objectid
, extent_key
.offset
);
8069 trace_btrfs_reserved_extent_alloc(fs_info
, extent_key
.objectid
,
8074 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle
*trans
,
8075 struct btrfs_root
*root
, u64 owner
,
8076 u64 offset
, u64 ram_bytes
,
8077 struct btrfs_key
*ins
)
8081 BUG_ON(root
->root_key
.objectid
== BTRFS_TREE_LOG_OBJECTID
);
8083 btrfs_ref_tree_mod(root
, ins
->objectid
, ins
->offset
, 0,
8084 root
->root_key
.objectid
, owner
, offset
,
8085 BTRFS_ADD_DELAYED_EXTENT
);
8087 ret
= btrfs_add_delayed_data_ref(trans
, ins
->objectid
,
8089 root
->root_key
.objectid
, owner
,
8091 BTRFS_ADD_DELAYED_EXTENT
, NULL
, NULL
);
8096 * this is used by the tree logging recovery code. It records that
8097 * an extent has been allocated and makes sure to clear the free
8098 * space cache bits as well
8100 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle
*trans
,
8101 u64 root_objectid
, u64 owner
, u64 offset
,
8102 struct btrfs_key
*ins
)
8104 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
8106 struct btrfs_block_group_cache
*block_group
;
8107 struct btrfs_space_info
*space_info
;
8110 * Mixed block groups will exclude before processing the log so we only
8111 * need to do the exclude dance if this fs isn't mixed.
8113 if (!btrfs_fs_incompat(fs_info
, MIXED_GROUPS
)) {
8114 ret
= __exclude_logged_extent(fs_info
, ins
->objectid
,
8120 block_group
= btrfs_lookup_block_group(fs_info
, ins
->objectid
);
8124 space_info
= block_group
->space_info
;
8125 spin_lock(&space_info
->lock
);
8126 spin_lock(&block_group
->lock
);
8127 space_info
->bytes_reserved
+= ins
->offset
;
8128 block_group
->reserved
+= ins
->offset
;
8129 spin_unlock(&block_group
->lock
);
8130 spin_unlock(&space_info
->lock
);
8132 ret
= alloc_reserved_file_extent(trans
, 0, root_objectid
, 0, owner
,
8134 btrfs_put_block_group(block_group
);
8138 static struct extent_buffer
*
8139 btrfs_init_new_buffer(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
8140 u64 bytenr
, int level
, u64 owner
)
8142 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8143 struct extent_buffer
*buf
;
8145 buf
= btrfs_find_create_tree_block(fs_info
, bytenr
);
8150 * Extra safety check in case the extent tree is corrupted and extent
8151 * allocator chooses to use a tree block which is already used and
8154 if (buf
->lock_owner
== current
->pid
) {
8155 btrfs_err_rl(fs_info
,
8156 "tree block %llu owner %llu already locked by pid=%d, extent tree corruption detected",
8157 buf
->start
, btrfs_header_owner(buf
), current
->pid
);
8158 free_extent_buffer(buf
);
8159 return ERR_PTR(-EUCLEAN
);
8162 btrfs_set_buffer_lockdep_class(root
->root_key
.objectid
, buf
, level
);
8163 btrfs_tree_lock(buf
);
8164 clean_tree_block(fs_info
, buf
);
8165 clear_bit(EXTENT_BUFFER_STALE
, &buf
->bflags
);
8167 btrfs_set_lock_blocking(buf
);
8168 set_extent_buffer_uptodate(buf
);
8170 memzero_extent_buffer(buf
, 0, sizeof(struct btrfs_header
));
8171 btrfs_set_header_level(buf
, level
);
8172 btrfs_set_header_bytenr(buf
, buf
->start
);
8173 btrfs_set_header_generation(buf
, trans
->transid
);
8174 btrfs_set_header_backref_rev(buf
, BTRFS_MIXED_BACKREF_REV
);
8175 btrfs_set_header_owner(buf
, owner
);
8176 write_extent_buffer_fsid(buf
, fs_info
->fsid
);
8177 write_extent_buffer_chunk_tree_uuid(buf
, fs_info
->chunk_tree_uuid
);
8178 if (root
->root_key
.objectid
== BTRFS_TREE_LOG_OBJECTID
) {
8179 buf
->log_index
= root
->log_transid
% 2;
8181 * we allow two log transactions at a time, use different
8182 * EXENT bit to differentiate dirty pages.
8184 if (buf
->log_index
== 0)
8185 set_extent_dirty(&root
->dirty_log_pages
, buf
->start
,
8186 buf
->start
+ buf
->len
- 1, GFP_NOFS
);
8188 set_extent_new(&root
->dirty_log_pages
, buf
->start
,
8189 buf
->start
+ buf
->len
- 1);
8191 buf
->log_index
= -1;
8192 set_extent_dirty(&trans
->transaction
->dirty_pages
, buf
->start
,
8193 buf
->start
+ buf
->len
- 1, GFP_NOFS
);
8195 trans
->dirty
= true;
8196 /* this returns a buffer locked for blocking */
8200 static struct btrfs_block_rsv
*
8201 use_block_rsv(struct btrfs_trans_handle
*trans
,
8202 struct btrfs_root
*root
, u32 blocksize
)
8204 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8205 struct btrfs_block_rsv
*block_rsv
;
8206 struct btrfs_block_rsv
*global_rsv
= &fs_info
->global_block_rsv
;
8208 bool global_updated
= false;
8210 block_rsv
= get_block_rsv(trans
, root
);
8212 if (unlikely(block_rsv
->size
== 0))
8215 ret
= block_rsv_use_bytes(block_rsv
, blocksize
);
8219 if (block_rsv
->failfast
)
8220 return ERR_PTR(ret
);
8222 if (block_rsv
->type
== BTRFS_BLOCK_RSV_GLOBAL
&& !global_updated
) {
8223 global_updated
= true;
8224 update_global_block_rsv(fs_info
);
8228 if (btrfs_test_opt(fs_info
, ENOSPC_DEBUG
)) {
8229 static DEFINE_RATELIMIT_STATE(_rs
,
8230 DEFAULT_RATELIMIT_INTERVAL
* 10,
8231 /*DEFAULT_RATELIMIT_BURST*/ 1);
8232 if (__ratelimit(&_rs
))
8234 "BTRFS: block rsv returned %d\n", ret
);
8237 ret
= reserve_metadata_bytes(root
, block_rsv
, blocksize
,
8238 BTRFS_RESERVE_NO_FLUSH
);
8242 * If we couldn't reserve metadata bytes try and use some from
8243 * the global reserve if its space type is the same as the global
8246 if (block_rsv
->type
!= BTRFS_BLOCK_RSV_GLOBAL
&&
8247 block_rsv
->space_info
== global_rsv
->space_info
) {
8248 ret
= block_rsv_use_bytes(global_rsv
, blocksize
);
8252 return ERR_PTR(ret
);
8255 static void unuse_block_rsv(struct btrfs_fs_info
*fs_info
,
8256 struct btrfs_block_rsv
*block_rsv
, u32 blocksize
)
8258 block_rsv_add_bytes(block_rsv
, blocksize
, false);
8259 block_rsv_release_bytes(fs_info
, block_rsv
, NULL
, 0, NULL
);
8263 * finds a free extent and does all the dirty work required for allocation
8264 * returns the tree buffer or an ERR_PTR on error.
8266 struct extent_buffer
*btrfs_alloc_tree_block(struct btrfs_trans_handle
*trans
,
8267 struct btrfs_root
*root
,
8268 u64 parent
, u64 root_objectid
,
8269 const struct btrfs_disk_key
*key
,
8270 int level
, u64 hint
,
8273 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8274 struct btrfs_key ins
;
8275 struct btrfs_block_rsv
*block_rsv
;
8276 struct extent_buffer
*buf
;
8277 struct btrfs_delayed_extent_op
*extent_op
;
8280 u32 blocksize
= fs_info
->nodesize
;
8281 bool skinny_metadata
= btrfs_fs_incompat(fs_info
, SKINNY_METADATA
);
8283 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
8284 if (btrfs_is_testing(fs_info
)) {
8285 buf
= btrfs_init_new_buffer(trans
, root
, root
->alloc_bytenr
,
8286 level
, root_objectid
);
8288 root
->alloc_bytenr
+= blocksize
;
8293 block_rsv
= use_block_rsv(trans
, root
, blocksize
);
8294 if (IS_ERR(block_rsv
))
8295 return ERR_CAST(block_rsv
);
8297 ret
= btrfs_reserve_extent(root
, blocksize
, blocksize
, blocksize
,
8298 empty_size
, hint
, &ins
, 0, 0);
8302 buf
= btrfs_init_new_buffer(trans
, root
, ins
.objectid
, level
,
8306 goto out_free_reserved
;
8309 if (root_objectid
== BTRFS_TREE_RELOC_OBJECTID
) {
8311 parent
= ins
.objectid
;
8312 flags
|= BTRFS_BLOCK_FLAG_FULL_BACKREF
;
8316 if (root_objectid
!= BTRFS_TREE_LOG_OBJECTID
) {
8317 extent_op
= btrfs_alloc_delayed_extent_op();
8323 memcpy(&extent_op
->key
, key
, sizeof(extent_op
->key
));
8325 memset(&extent_op
->key
, 0, sizeof(extent_op
->key
));
8326 extent_op
->flags_to_set
= flags
;
8327 extent_op
->update_key
= skinny_metadata
? false : true;
8328 extent_op
->update_flags
= true;
8329 extent_op
->is_data
= false;
8330 extent_op
->level
= level
;
8332 btrfs_ref_tree_mod(root
, ins
.objectid
, ins
.offset
, parent
,
8333 root_objectid
, level
, 0,
8334 BTRFS_ADD_DELAYED_EXTENT
);
8335 ret
= btrfs_add_delayed_tree_ref(trans
, ins
.objectid
,
8337 root_objectid
, level
,
8338 BTRFS_ADD_DELAYED_EXTENT
,
8339 extent_op
, NULL
, NULL
);
8341 goto out_free_delayed
;
8346 btrfs_free_delayed_extent_op(extent_op
);
8348 free_extent_buffer(buf
);
8350 btrfs_free_reserved_extent(fs_info
, ins
.objectid
, ins
.offset
, 0);
8352 unuse_block_rsv(fs_info
, block_rsv
, blocksize
);
8353 return ERR_PTR(ret
);
8356 struct walk_control
{
8357 u64 refs
[BTRFS_MAX_LEVEL
];
8358 u64 flags
[BTRFS_MAX_LEVEL
];
8359 struct btrfs_key update_progress
;
8369 #define DROP_REFERENCE 1
8370 #define UPDATE_BACKREF 2
8372 static noinline
void reada_walk_down(struct btrfs_trans_handle
*trans
,
8373 struct btrfs_root
*root
,
8374 struct walk_control
*wc
,
8375 struct btrfs_path
*path
)
8377 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8383 struct btrfs_key key
;
8384 struct extent_buffer
*eb
;
8389 if (path
->slots
[wc
->level
] < wc
->reada_slot
) {
8390 wc
->reada_count
= wc
->reada_count
* 2 / 3;
8391 wc
->reada_count
= max(wc
->reada_count
, 2);
8393 wc
->reada_count
= wc
->reada_count
* 3 / 2;
8394 wc
->reada_count
= min_t(int, wc
->reada_count
,
8395 BTRFS_NODEPTRS_PER_BLOCK(fs_info
));
8398 eb
= path
->nodes
[wc
->level
];
8399 nritems
= btrfs_header_nritems(eb
);
8401 for (slot
= path
->slots
[wc
->level
]; slot
< nritems
; slot
++) {
8402 if (nread
>= wc
->reada_count
)
8406 bytenr
= btrfs_node_blockptr(eb
, slot
);
8407 generation
= btrfs_node_ptr_generation(eb
, slot
);
8409 if (slot
== path
->slots
[wc
->level
])
8412 if (wc
->stage
== UPDATE_BACKREF
&&
8413 generation
<= root
->root_key
.offset
)
8416 /* We don't lock the tree block, it's OK to be racy here */
8417 ret
= btrfs_lookup_extent_info(trans
, fs_info
, bytenr
,
8418 wc
->level
- 1, 1, &refs
,
8420 /* We don't care about errors in readahead. */
8425 if (wc
->stage
== DROP_REFERENCE
) {
8429 if (wc
->level
== 1 &&
8430 (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
))
8432 if (!wc
->update_ref
||
8433 generation
<= root
->root_key
.offset
)
8435 btrfs_node_key_to_cpu(eb
, &key
, slot
);
8436 ret
= btrfs_comp_cpu_keys(&key
,
8437 &wc
->update_progress
);
8441 if (wc
->level
== 1 &&
8442 (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
))
8446 readahead_tree_block(fs_info
, bytenr
);
8449 wc
->reada_slot
= slot
;
8453 * helper to process tree block while walking down the tree.
8455 * when wc->stage == UPDATE_BACKREF, this function updates
8456 * back refs for pointers in the block.
8458 * NOTE: return value 1 means we should stop walking down.
8460 static noinline
int walk_down_proc(struct btrfs_trans_handle
*trans
,
8461 struct btrfs_root
*root
,
8462 struct btrfs_path
*path
,
8463 struct walk_control
*wc
, int lookup_info
)
8465 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8466 int level
= wc
->level
;
8467 struct extent_buffer
*eb
= path
->nodes
[level
];
8468 u64 flag
= BTRFS_BLOCK_FLAG_FULL_BACKREF
;
8471 if (wc
->stage
== UPDATE_BACKREF
&&
8472 btrfs_header_owner(eb
) != root
->root_key
.objectid
)
8476 * when reference count of tree block is 1, it won't increase
8477 * again. once full backref flag is set, we never clear it.
8480 ((wc
->stage
== DROP_REFERENCE
&& wc
->refs
[level
] != 1) ||
8481 (wc
->stage
== UPDATE_BACKREF
&& !(wc
->flags
[level
] & flag
)))) {
8482 BUG_ON(!path
->locks
[level
]);
8483 ret
= btrfs_lookup_extent_info(trans
, fs_info
,
8484 eb
->start
, level
, 1,
8487 BUG_ON(ret
== -ENOMEM
);
8490 BUG_ON(wc
->refs
[level
] == 0);
8493 if (wc
->stage
== DROP_REFERENCE
) {
8494 if (wc
->refs
[level
] > 1)
8497 if (path
->locks
[level
] && !wc
->keep_locks
) {
8498 btrfs_tree_unlock_rw(eb
, path
->locks
[level
]);
8499 path
->locks
[level
] = 0;
8504 /* wc->stage == UPDATE_BACKREF */
8505 if (!(wc
->flags
[level
] & flag
)) {
8506 BUG_ON(!path
->locks
[level
]);
8507 ret
= btrfs_inc_ref(trans
, root
, eb
, 1);
8508 BUG_ON(ret
); /* -ENOMEM */
8509 ret
= btrfs_dec_ref(trans
, root
, eb
, 0);
8510 BUG_ON(ret
); /* -ENOMEM */
8511 ret
= btrfs_set_disk_extent_flags(trans
, fs_info
, eb
->start
,
8513 btrfs_header_level(eb
), 0);
8514 BUG_ON(ret
); /* -ENOMEM */
8515 wc
->flags
[level
] |= flag
;
8519 * the block is shared by multiple trees, so it's not good to
8520 * keep the tree lock
8522 if (path
->locks
[level
] && level
> 0) {
8523 btrfs_tree_unlock_rw(eb
, path
->locks
[level
]);
8524 path
->locks
[level
] = 0;
8530 * helper to process tree block pointer.
8532 * when wc->stage == DROP_REFERENCE, this function checks
8533 * reference count of the block pointed to. if the block
8534 * is shared and we need update back refs for the subtree
8535 * rooted at the block, this function changes wc->stage to
8536 * UPDATE_BACKREF. if the block is shared and there is no
8537 * need to update back, this function drops the reference
8540 * NOTE: return value 1 means we should stop walking down.
8542 static noinline
int do_walk_down(struct btrfs_trans_handle
*trans
,
8543 struct btrfs_root
*root
,
8544 struct btrfs_path
*path
,
8545 struct walk_control
*wc
, int *lookup_info
)
8547 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8552 struct btrfs_key key
;
8553 struct btrfs_key first_key
;
8554 struct extent_buffer
*next
;
8555 int level
= wc
->level
;
8558 bool need_account
= false;
8560 generation
= btrfs_node_ptr_generation(path
->nodes
[level
],
8561 path
->slots
[level
]);
8563 * if the lower level block was created before the snapshot
8564 * was created, we know there is no need to update back refs
8567 if (wc
->stage
== UPDATE_BACKREF
&&
8568 generation
<= root
->root_key
.offset
) {
8573 bytenr
= btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]);
8574 btrfs_node_key_to_cpu(path
->nodes
[level
], &first_key
,
8575 path
->slots
[level
]);
8576 blocksize
= fs_info
->nodesize
;
8578 next
= find_extent_buffer(fs_info
, bytenr
);
8580 next
= btrfs_find_create_tree_block(fs_info
, bytenr
);
8582 return PTR_ERR(next
);
8584 btrfs_set_buffer_lockdep_class(root
->root_key
.objectid
, next
,
8588 btrfs_tree_lock(next
);
8589 btrfs_set_lock_blocking(next
);
8591 ret
= btrfs_lookup_extent_info(trans
, fs_info
, bytenr
, level
- 1, 1,
8592 &wc
->refs
[level
- 1],
8593 &wc
->flags
[level
- 1]);
8597 if (unlikely(wc
->refs
[level
- 1] == 0)) {
8598 btrfs_err(fs_info
, "Missing references.");
8604 if (wc
->stage
== DROP_REFERENCE
) {
8605 if (wc
->refs
[level
- 1] > 1) {
8606 need_account
= true;
8608 (wc
->flags
[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF
))
8611 if (!wc
->update_ref
||
8612 generation
<= root
->root_key
.offset
)
8615 btrfs_node_key_to_cpu(path
->nodes
[level
], &key
,
8616 path
->slots
[level
]);
8617 ret
= btrfs_comp_cpu_keys(&key
, &wc
->update_progress
);
8621 wc
->stage
= UPDATE_BACKREF
;
8622 wc
->shared_level
= level
- 1;
8626 (wc
->flags
[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF
))
8630 if (!btrfs_buffer_uptodate(next
, generation
, 0)) {
8631 btrfs_tree_unlock(next
);
8632 free_extent_buffer(next
);
8638 if (reada
&& level
== 1)
8639 reada_walk_down(trans
, root
, wc
, path
);
8640 next
= read_tree_block(fs_info
, bytenr
, generation
, level
- 1,
8643 return PTR_ERR(next
);
8644 } else if (!extent_buffer_uptodate(next
)) {
8645 free_extent_buffer(next
);
8648 btrfs_tree_lock(next
);
8649 btrfs_set_lock_blocking(next
);
8653 ASSERT(level
== btrfs_header_level(next
));
8654 if (level
!= btrfs_header_level(next
)) {
8655 btrfs_err(root
->fs_info
, "mismatched level");
8659 path
->nodes
[level
] = next
;
8660 path
->slots
[level
] = 0;
8661 path
->locks
[level
] = BTRFS_WRITE_LOCK_BLOCKING
;
8667 wc
->refs
[level
- 1] = 0;
8668 wc
->flags
[level
- 1] = 0;
8669 if (wc
->stage
== DROP_REFERENCE
) {
8670 if (wc
->flags
[level
] & BTRFS_BLOCK_FLAG_FULL_BACKREF
) {
8671 parent
= path
->nodes
[level
]->start
;
8673 ASSERT(root
->root_key
.objectid
==
8674 btrfs_header_owner(path
->nodes
[level
]));
8675 if (root
->root_key
.objectid
!=
8676 btrfs_header_owner(path
->nodes
[level
])) {
8677 btrfs_err(root
->fs_info
,
8678 "mismatched block owner");
8686 * Reloc tree doesn't contribute to qgroup numbers, and we have
8687 * already accounted them at merge time (replace_path),
8688 * thus we could skip expensive subtree trace here.
8690 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
&&
8692 ret
= btrfs_qgroup_trace_subtree(trans
, next
,
8693 generation
, level
- 1);
8695 btrfs_err_rl(fs_info
,
8696 "Error %d accounting shared subtree. Quota is out of sync, rescan required.",
8700 ret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
,
8701 parent
, root
->root_key
.objectid
,
8711 btrfs_tree_unlock(next
);
8712 free_extent_buffer(next
);
8718 * helper to process tree block while walking up the tree.
8720 * when wc->stage == DROP_REFERENCE, this function drops
8721 * reference count on the block.
8723 * when wc->stage == UPDATE_BACKREF, this function changes
8724 * wc->stage back to DROP_REFERENCE if we changed wc->stage
8725 * to UPDATE_BACKREF previously while processing the block.
8727 * NOTE: return value 1 means we should stop walking up.
8729 static noinline
int walk_up_proc(struct btrfs_trans_handle
*trans
,
8730 struct btrfs_root
*root
,
8731 struct btrfs_path
*path
,
8732 struct walk_control
*wc
)
8734 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8736 int level
= wc
->level
;
8737 struct extent_buffer
*eb
= path
->nodes
[level
];
8740 if (wc
->stage
== UPDATE_BACKREF
) {
8741 BUG_ON(wc
->shared_level
< level
);
8742 if (level
< wc
->shared_level
)
8745 ret
= find_next_key(path
, level
+ 1, &wc
->update_progress
);
8749 wc
->stage
= DROP_REFERENCE
;
8750 wc
->shared_level
= -1;
8751 path
->slots
[level
] = 0;
8754 * check reference count again if the block isn't locked.
8755 * we should start walking down the tree again if reference
8758 if (!path
->locks
[level
]) {
8760 btrfs_tree_lock(eb
);
8761 btrfs_set_lock_blocking(eb
);
8762 path
->locks
[level
] = BTRFS_WRITE_LOCK_BLOCKING
;
8764 ret
= btrfs_lookup_extent_info(trans
, fs_info
,
8765 eb
->start
, level
, 1,
8769 btrfs_tree_unlock_rw(eb
, path
->locks
[level
]);
8770 path
->locks
[level
] = 0;
8773 BUG_ON(wc
->refs
[level
] == 0);
8774 if (wc
->refs
[level
] == 1) {
8775 btrfs_tree_unlock_rw(eb
, path
->locks
[level
]);
8776 path
->locks
[level
] = 0;
8782 /* wc->stage == DROP_REFERENCE */
8783 BUG_ON(wc
->refs
[level
] > 1 && !path
->locks
[level
]);
8785 if (wc
->refs
[level
] == 1) {
8787 if (wc
->flags
[level
] & BTRFS_BLOCK_FLAG_FULL_BACKREF
)
8788 ret
= btrfs_dec_ref(trans
, root
, eb
, 1);
8790 ret
= btrfs_dec_ref(trans
, root
, eb
, 0);
8791 BUG_ON(ret
); /* -ENOMEM */
8792 ret
= btrfs_qgroup_trace_leaf_items(trans
, eb
);
8794 btrfs_err_rl(fs_info
,
8795 "error %d accounting leaf items. Quota is out of sync, rescan required.",
8799 /* make block locked assertion in clean_tree_block happy */
8800 if (!path
->locks
[level
] &&
8801 btrfs_header_generation(eb
) == trans
->transid
) {
8802 btrfs_tree_lock(eb
);
8803 btrfs_set_lock_blocking(eb
);
8804 path
->locks
[level
] = BTRFS_WRITE_LOCK_BLOCKING
;
8806 clean_tree_block(fs_info
, eb
);
8809 if (eb
== root
->node
) {
8810 if (wc
->flags
[level
] & BTRFS_BLOCK_FLAG_FULL_BACKREF
)
8812 else if (root
->root_key
.objectid
!= btrfs_header_owner(eb
))
8813 goto owner_mismatch
;
8815 if (wc
->flags
[level
+ 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF
)
8816 parent
= path
->nodes
[level
+ 1]->start
;
8817 else if (root
->root_key
.objectid
!=
8818 btrfs_header_owner(path
->nodes
[level
+ 1]))
8819 goto owner_mismatch
;
8822 btrfs_free_tree_block(trans
, root
, eb
, parent
, wc
->refs
[level
] == 1);
8824 wc
->refs
[level
] = 0;
8825 wc
->flags
[level
] = 0;
8829 btrfs_err_rl(fs_info
, "unexpected tree owner, have %llu expect %llu",
8830 btrfs_header_owner(eb
), root
->root_key
.objectid
);
8834 static noinline
int walk_down_tree(struct btrfs_trans_handle
*trans
,
8835 struct btrfs_root
*root
,
8836 struct btrfs_path
*path
,
8837 struct walk_control
*wc
)
8839 int level
= wc
->level
;
8840 int lookup_info
= 1;
8843 while (level
>= 0) {
8844 ret
= walk_down_proc(trans
, root
, path
, wc
, lookup_info
);
8851 if (path
->slots
[level
] >=
8852 btrfs_header_nritems(path
->nodes
[level
]))
8855 ret
= do_walk_down(trans
, root
, path
, wc
, &lookup_info
);
8857 path
->slots
[level
]++;
8866 static noinline
int walk_up_tree(struct btrfs_trans_handle
*trans
,
8867 struct btrfs_root
*root
,
8868 struct btrfs_path
*path
,
8869 struct walk_control
*wc
, int max_level
)
8871 int level
= wc
->level
;
8874 path
->slots
[level
] = btrfs_header_nritems(path
->nodes
[level
]);
8875 while (level
< max_level
&& path
->nodes
[level
]) {
8877 if (path
->slots
[level
] + 1 <
8878 btrfs_header_nritems(path
->nodes
[level
])) {
8879 path
->slots
[level
]++;
8882 ret
= walk_up_proc(trans
, root
, path
, wc
);
8888 if (path
->locks
[level
]) {
8889 btrfs_tree_unlock_rw(path
->nodes
[level
],
8890 path
->locks
[level
]);
8891 path
->locks
[level
] = 0;
8893 free_extent_buffer(path
->nodes
[level
]);
8894 path
->nodes
[level
] = NULL
;
8902 * drop a subvolume tree.
8904 * this function traverses the tree freeing any blocks that only
8905 * referenced by the tree.
8907 * when a shared tree block is found. this function decreases its
8908 * reference count by one. if update_ref is true, this function
8909 * also make sure backrefs for the shared block and all lower level
8910 * blocks are properly updated.
8912 * If called with for_reloc == 0, may exit early with -EAGAIN
8914 int btrfs_drop_snapshot(struct btrfs_root
*root
,
8915 struct btrfs_block_rsv
*block_rsv
, int update_ref
,
8918 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
8919 struct btrfs_path
*path
;
8920 struct btrfs_trans_handle
*trans
;
8921 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
8922 struct btrfs_root_item
*root_item
= &root
->root_item
;
8923 struct walk_control
*wc
;
8924 struct btrfs_key key
;
8928 bool root_dropped
= false;
8930 btrfs_debug(fs_info
, "Drop subvolume %llu", root
->root_key
.objectid
);
8932 path
= btrfs_alloc_path();
8938 wc
= kzalloc(sizeof(*wc
), GFP_NOFS
);
8940 btrfs_free_path(path
);
8945 trans
= btrfs_start_transaction(tree_root
, 0);
8946 if (IS_ERR(trans
)) {
8947 err
= PTR_ERR(trans
);
8952 trans
->block_rsv
= block_rsv
;
8954 if (btrfs_disk_key_objectid(&root_item
->drop_progress
) == 0) {
8955 level
= btrfs_header_level(root
->node
);
8956 path
->nodes
[level
] = btrfs_lock_root_node(root
);
8957 btrfs_set_lock_blocking(path
->nodes
[level
]);
8958 path
->slots
[level
] = 0;
8959 path
->locks
[level
] = BTRFS_WRITE_LOCK_BLOCKING
;
8960 memset(&wc
->update_progress
, 0,
8961 sizeof(wc
->update_progress
));
8963 btrfs_disk_key_to_cpu(&key
, &root_item
->drop_progress
);
8964 memcpy(&wc
->update_progress
, &key
,
8965 sizeof(wc
->update_progress
));
8967 level
= root_item
->drop_level
;
8969 path
->lowest_level
= level
;
8970 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
8971 path
->lowest_level
= 0;
8979 * unlock our path, this is safe because only this
8980 * function is allowed to delete this snapshot
8982 btrfs_unlock_up_safe(path
, 0);
8984 level
= btrfs_header_level(root
->node
);
8986 btrfs_tree_lock(path
->nodes
[level
]);
8987 btrfs_set_lock_blocking(path
->nodes
[level
]);
8988 path
->locks
[level
] = BTRFS_WRITE_LOCK_BLOCKING
;
8990 ret
= btrfs_lookup_extent_info(trans
, fs_info
,
8991 path
->nodes
[level
]->start
,
8992 level
, 1, &wc
->refs
[level
],
8998 BUG_ON(wc
->refs
[level
] == 0);
9000 if (level
== root_item
->drop_level
)
9003 btrfs_tree_unlock(path
->nodes
[level
]);
9004 path
->locks
[level
] = 0;
9005 WARN_ON(wc
->refs
[level
] != 1);
9011 wc
->shared_level
= -1;
9012 wc
->stage
= DROP_REFERENCE
;
9013 wc
->update_ref
= update_ref
;
9015 wc
->reada_count
= BTRFS_NODEPTRS_PER_BLOCK(fs_info
);
9019 ret
= walk_down_tree(trans
, root
, path
, wc
);
9025 ret
= walk_up_tree(trans
, root
, path
, wc
, BTRFS_MAX_LEVEL
);
9032 BUG_ON(wc
->stage
!= DROP_REFERENCE
);
9036 if (wc
->stage
== DROP_REFERENCE
) {
9038 btrfs_node_key(path
->nodes
[level
],
9039 &root_item
->drop_progress
,
9040 path
->slots
[level
]);
9041 root_item
->drop_level
= level
;
9044 BUG_ON(wc
->level
== 0);
9045 if (btrfs_should_end_transaction(trans
) ||
9046 (!for_reloc
&& btrfs_need_cleaner_sleep(fs_info
))) {
9047 ret
= btrfs_update_root(trans
, tree_root
,
9051 btrfs_abort_transaction(trans
, ret
);
9056 btrfs_end_transaction_throttle(trans
);
9057 if (!for_reloc
&& btrfs_need_cleaner_sleep(fs_info
)) {
9058 btrfs_debug(fs_info
,
9059 "drop snapshot early exit");
9064 trans
= btrfs_start_transaction(tree_root
, 0);
9065 if (IS_ERR(trans
)) {
9066 err
= PTR_ERR(trans
);
9070 trans
->block_rsv
= block_rsv
;
9073 btrfs_release_path(path
);
9077 ret
= btrfs_del_root(trans
, &root
->root_key
);
9079 btrfs_abort_transaction(trans
, ret
);
9084 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
) {
9085 ret
= btrfs_find_root(tree_root
, &root
->root_key
, path
,
9088 btrfs_abort_transaction(trans
, ret
);
9091 } else if (ret
> 0) {
9092 /* if we fail to delete the orphan item this time
9093 * around, it'll get picked up the next time.
9095 * The most common failure here is just -ENOENT.
9097 btrfs_del_orphan_item(trans
, tree_root
,
9098 root
->root_key
.objectid
);
9102 if (test_bit(BTRFS_ROOT_IN_RADIX
, &root
->state
)) {
9103 btrfs_add_dropped_root(trans
, root
);
9105 free_extent_buffer(root
->node
);
9106 free_extent_buffer(root
->commit_root
);
9107 btrfs_put_fs_root(root
);
9109 root_dropped
= true;
9111 btrfs_end_transaction_throttle(trans
);
9114 btrfs_free_path(path
);
9117 * So if we need to stop dropping the snapshot for whatever reason we
9118 * need to make sure to add it back to the dead root list so that we
9119 * keep trying to do the work later. This also cleans up roots if we
9120 * don't have it in the radix (like when we recover after a power fail
9121 * or unmount) so we don't leak memory.
9123 if (!for_reloc
&& !root_dropped
)
9124 btrfs_add_dead_root(root
);
9125 if (err
&& err
!= -EAGAIN
)
9126 btrfs_handle_fs_error(fs_info
, err
, NULL
);
9131 * drop subtree rooted at tree block 'node'.
9133 * NOTE: this function will unlock and release tree block 'node'
9134 * only used by relocation code
9136 int btrfs_drop_subtree(struct btrfs_trans_handle
*trans
,
9137 struct btrfs_root
*root
,
9138 struct extent_buffer
*node
,
9139 struct extent_buffer
*parent
)
9141 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
9142 struct btrfs_path
*path
;
9143 struct walk_control
*wc
;
9149 BUG_ON(root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
);
9151 path
= btrfs_alloc_path();
9155 wc
= kzalloc(sizeof(*wc
), GFP_NOFS
);
9157 btrfs_free_path(path
);
9161 btrfs_assert_tree_locked(parent
);
9162 parent_level
= btrfs_header_level(parent
);
9163 extent_buffer_get(parent
);
9164 path
->nodes
[parent_level
] = parent
;
9165 path
->slots
[parent_level
] = btrfs_header_nritems(parent
);
9167 btrfs_assert_tree_locked(node
);
9168 level
= btrfs_header_level(node
);
9169 path
->nodes
[level
] = node
;
9170 path
->slots
[level
] = 0;
9171 path
->locks
[level
] = BTRFS_WRITE_LOCK_BLOCKING
;
9173 wc
->refs
[parent_level
] = 1;
9174 wc
->flags
[parent_level
] = BTRFS_BLOCK_FLAG_FULL_BACKREF
;
9176 wc
->shared_level
= -1;
9177 wc
->stage
= DROP_REFERENCE
;
9180 wc
->reada_count
= BTRFS_NODEPTRS_PER_BLOCK(fs_info
);
9183 wret
= walk_down_tree(trans
, root
, path
, wc
);
9189 wret
= walk_up_tree(trans
, root
, path
, wc
, parent_level
);
9197 btrfs_free_path(path
);
9201 static u64
update_block_group_flags(struct btrfs_fs_info
*fs_info
, u64 flags
)
9207 * if restripe for this chunk_type is on pick target profile and
9208 * return, otherwise do the usual balance
9210 stripped
= get_restripe_target(fs_info
, flags
);
9212 return extended_to_chunk(stripped
);
9214 num_devices
= fs_info
->fs_devices
->rw_devices
;
9216 stripped
= BTRFS_BLOCK_GROUP_RAID0
|
9217 BTRFS_BLOCK_GROUP_RAID5
| BTRFS_BLOCK_GROUP_RAID6
|
9218 BTRFS_BLOCK_GROUP_RAID1
| BTRFS_BLOCK_GROUP_RAID10
;
9220 if (num_devices
== 1) {
9221 stripped
|= BTRFS_BLOCK_GROUP_DUP
;
9222 stripped
= flags
& ~stripped
;
9224 /* turn raid0 into single device chunks */
9225 if (flags
& BTRFS_BLOCK_GROUP_RAID0
)
9228 /* turn mirroring into duplication */
9229 if (flags
& (BTRFS_BLOCK_GROUP_RAID1
|
9230 BTRFS_BLOCK_GROUP_RAID10
))
9231 return stripped
| BTRFS_BLOCK_GROUP_DUP
;
9233 /* they already had raid on here, just return */
9234 if (flags
& stripped
)
9237 stripped
|= BTRFS_BLOCK_GROUP_DUP
;
9238 stripped
= flags
& ~stripped
;
9240 /* switch duplicated blocks with raid1 */
9241 if (flags
& BTRFS_BLOCK_GROUP_DUP
)
9242 return stripped
| BTRFS_BLOCK_GROUP_RAID1
;
9244 /* this is drive concat, leave it alone */
9250 static int inc_block_group_ro(struct btrfs_block_group_cache
*cache
, int force
)
9252 struct btrfs_space_info
*sinfo
= cache
->space_info
;
9254 u64 min_allocable_bytes
;
9258 * We need some metadata space and system metadata space for
9259 * allocating chunks in some corner cases until we force to set
9260 * it to be readonly.
9263 (BTRFS_BLOCK_GROUP_SYSTEM
| BTRFS_BLOCK_GROUP_METADATA
)) &&
9265 min_allocable_bytes
= SZ_1M
;
9267 min_allocable_bytes
= 0;
9269 spin_lock(&sinfo
->lock
);
9270 spin_lock(&cache
->lock
);
9278 num_bytes
= cache
->key
.offset
- cache
->reserved
- cache
->pinned
-
9279 cache
->bytes_super
- btrfs_block_group_used(&cache
->item
);
9281 if (btrfs_space_info_used(sinfo
, true) + num_bytes
+
9282 min_allocable_bytes
<= sinfo
->total_bytes
) {
9283 sinfo
->bytes_readonly
+= num_bytes
;
9285 list_add_tail(&cache
->ro_list
, &sinfo
->ro_bgs
);
9289 spin_unlock(&cache
->lock
);
9290 spin_unlock(&sinfo
->lock
);
9294 int btrfs_inc_block_group_ro(struct btrfs_block_group_cache
*cache
)
9297 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
9298 struct btrfs_trans_handle
*trans
;
9303 trans
= btrfs_join_transaction(fs_info
->extent_root
);
9305 return PTR_ERR(trans
);
9308 * we're not allowed to set block groups readonly after the dirty
9309 * block groups cache has started writing. If it already started,
9310 * back off and let this transaction commit
9312 mutex_lock(&fs_info
->ro_block_group_mutex
);
9313 if (test_bit(BTRFS_TRANS_DIRTY_BG_RUN
, &trans
->transaction
->flags
)) {
9314 u64 transid
= trans
->transid
;
9316 mutex_unlock(&fs_info
->ro_block_group_mutex
);
9317 btrfs_end_transaction(trans
);
9319 ret
= btrfs_wait_for_commit(fs_info
, transid
);
9326 * if we are changing raid levels, try to allocate a corresponding
9327 * block group with the new raid level.
9329 alloc_flags
= update_block_group_flags(fs_info
, cache
->flags
);
9330 if (alloc_flags
!= cache
->flags
) {
9331 ret
= do_chunk_alloc(trans
, alloc_flags
,
9334 * ENOSPC is allowed here, we may have enough space
9335 * already allocated at the new raid level to
9344 ret
= inc_block_group_ro(cache
, 0);
9347 alloc_flags
= get_alloc_profile(fs_info
, cache
->space_info
->flags
);
9348 ret
= do_chunk_alloc(trans
, alloc_flags
, CHUNK_ALLOC_FORCE
);
9351 ret
= inc_block_group_ro(cache
, 0);
9353 if (cache
->flags
& BTRFS_BLOCK_GROUP_SYSTEM
) {
9354 alloc_flags
= update_block_group_flags(fs_info
, cache
->flags
);
9355 mutex_lock(&fs_info
->chunk_mutex
);
9356 check_system_chunk(trans
, alloc_flags
);
9357 mutex_unlock(&fs_info
->chunk_mutex
);
9359 mutex_unlock(&fs_info
->ro_block_group_mutex
);
9361 btrfs_end_transaction(trans
);
9365 int btrfs_force_chunk_alloc(struct btrfs_trans_handle
*trans
, u64 type
)
9367 u64 alloc_flags
= get_alloc_profile(trans
->fs_info
, type
);
9369 return do_chunk_alloc(trans
, alloc_flags
, CHUNK_ALLOC_FORCE
);
9373 * helper to account the unused space of all the readonly block group in the
9374 * space_info. takes mirrors into account.
9376 u64
btrfs_account_ro_block_groups_free_space(struct btrfs_space_info
*sinfo
)
9378 struct btrfs_block_group_cache
*block_group
;
9382 /* It's df, we don't care if it's racy */
9383 if (list_empty(&sinfo
->ro_bgs
))
9386 spin_lock(&sinfo
->lock
);
9387 list_for_each_entry(block_group
, &sinfo
->ro_bgs
, ro_list
) {
9388 spin_lock(&block_group
->lock
);
9390 if (!block_group
->ro
) {
9391 spin_unlock(&block_group
->lock
);
9395 factor
= btrfs_bg_type_to_factor(block_group
->flags
);
9396 free_bytes
+= (block_group
->key
.offset
-
9397 btrfs_block_group_used(&block_group
->item
)) *
9400 spin_unlock(&block_group
->lock
);
9402 spin_unlock(&sinfo
->lock
);
9407 void btrfs_dec_block_group_ro(struct btrfs_block_group_cache
*cache
)
9409 struct btrfs_space_info
*sinfo
= cache
->space_info
;
9414 spin_lock(&sinfo
->lock
);
9415 spin_lock(&cache
->lock
);
9417 num_bytes
= cache
->key
.offset
- cache
->reserved
-
9418 cache
->pinned
- cache
->bytes_super
-
9419 btrfs_block_group_used(&cache
->item
);
9420 sinfo
->bytes_readonly
-= num_bytes
;
9421 list_del_init(&cache
->ro_list
);
9423 spin_unlock(&cache
->lock
);
9424 spin_unlock(&sinfo
->lock
);
9428 * checks to see if its even possible to relocate this block group.
9430 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
9431 * ok to go ahead and try.
9433 int btrfs_can_relocate(struct btrfs_fs_info
*fs_info
, u64 bytenr
)
9435 struct btrfs_root
*root
= fs_info
->extent_root
;
9436 struct btrfs_block_group_cache
*block_group
;
9437 struct btrfs_space_info
*space_info
;
9438 struct btrfs_fs_devices
*fs_devices
= fs_info
->fs_devices
;
9439 struct btrfs_device
*device
;
9440 struct btrfs_trans_handle
*trans
;
9450 debug
= btrfs_test_opt(fs_info
, ENOSPC_DEBUG
);
9452 block_group
= btrfs_lookup_block_group(fs_info
, bytenr
);
9454 /* odd, couldn't find the block group, leave it alone */
9458 "can't find block group for bytenr %llu",
9463 min_free
= btrfs_block_group_used(&block_group
->item
);
9465 /* no bytes used, we're good */
9469 space_info
= block_group
->space_info
;
9470 spin_lock(&space_info
->lock
);
9472 full
= space_info
->full
;
9475 * if this is the last block group we have in this space, we can't
9476 * relocate it unless we're able to allocate a new chunk below.
9478 * Otherwise, we need to make sure we have room in the space to handle
9479 * all of the extents from this block group. If we can, we're good
9481 if ((space_info
->total_bytes
!= block_group
->key
.offset
) &&
9482 (btrfs_space_info_used(space_info
, false) + min_free
<
9483 space_info
->total_bytes
)) {
9484 spin_unlock(&space_info
->lock
);
9487 spin_unlock(&space_info
->lock
);
9490 * ok we don't have enough space, but maybe we have free space on our
9491 * devices to allocate new chunks for relocation, so loop through our
9492 * alloc devices and guess if we have enough space. if this block
9493 * group is going to be restriped, run checks against the target
9494 * profile instead of the current one.
9506 target
= get_restripe_target(fs_info
, block_group
->flags
);
9508 index
= btrfs_bg_flags_to_raid_index(extended_to_chunk(target
));
9511 * this is just a balance, so if we were marked as full
9512 * we know there is no space for a new chunk
9517 "no space to alloc new chunk for block group %llu",
9518 block_group
->key
.objectid
);
9522 index
= btrfs_bg_flags_to_raid_index(block_group
->flags
);
9525 if (index
== BTRFS_RAID_RAID10
) {
9529 } else if (index
== BTRFS_RAID_RAID1
) {
9531 } else if (index
== BTRFS_RAID_DUP
) {
9534 } else if (index
== BTRFS_RAID_RAID0
) {
9535 dev_min
= fs_devices
->rw_devices
;
9536 min_free
= div64_u64(min_free
, dev_min
);
9539 /* We need to do this so that we can look at pending chunks */
9540 trans
= btrfs_join_transaction(root
);
9541 if (IS_ERR(trans
)) {
9542 ret
= PTR_ERR(trans
);
9546 mutex_lock(&fs_info
->chunk_mutex
);
9547 list_for_each_entry(device
, &fs_devices
->alloc_list
, dev_alloc_list
) {
9551 * check to make sure we can actually find a chunk with enough
9552 * space to fit our block group in.
9554 if (device
->total_bytes
> device
->bytes_used
+ min_free
&&
9555 !test_bit(BTRFS_DEV_STATE_REPLACE_TGT
, &device
->dev_state
)) {
9556 ret
= find_free_dev_extent(trans
, device
, min_free
,
9561 if (dev_nr
>= dev_min
)
9567 if (debug
&& ret
== -1)
9569 "no space to allocate a new chunk for block group %llu",
9570 block_group
->key
.objectid
);
9571 mutex_unlock(&fs_info
->chunk_mutex
);
9572 btrfs_end_transaction(trans
);
9574 btrfs_put_block_group(block_group
);
9578 static int find_first_block_group(struct btrfs_fs_info
*fs_info
,
9579 struct btrfs_path
*path
,
9580 struct btrfs_key
*key
)
9582 struct btrfs_root
*root
= fs_info
->extent_root
;
9584 struct btrfs_key found_key
;
9585 struct extent_buffer
*leaf
;
9586 struct btrfs_block_group_item bg
;
9590 ret
= btrfs_search_slot(NULL
, root
, key
, path
, 0, 0);
9595 slot
= path
->slots
[0];
9596 leaf
= path
->nodes
[0];
9597 if (slot
>= btrfs_header_nritems(leaf
)) {
9598 ret
= btrfs_next_leaf(root
, path
);
9605 btrfs_item_key_to_cpu(leaf
, &found_key
, slot
);
9607 if (found_key
.objectid
>= key
->objectid
&&
9608 found_key
.type
== BTRFS_BLOCK_GROUP_ITEM_KEY
) {
9609 struct extent_map_tree
*em_tree
;
9610 struct extent_map
*em
;
9612 em_tree
= &root
->fs_info
->mapping_tree
.map_tree
;
9613 read_lock(&em_tree
->lock
);
9614 em
= lookup_extent_mapping(em_tree
, found_key
.objectid
,
9616 read_unlock(&em_tree
->lock
);
9619 "logical %llu len %llu found bg but no related chunk",
9620 found_key
.objectid
, found_key
.offset
);
9622 } else if (em
->start
!= found_key
.objectid
||
9623 em
->len
!= found_key
.offset
) {
9625 "block group %llu len %llu mismatch with chunk %llu len %llu",
9626 found_key
.objectid
, found_key
.offset
,
9627 em
->start
, em
->len
);
9630 read_extent_buffer(leaf
, &bg
,
9631 btrfs_item_ptr_offset(leaf
, slot
),
9633 flags
= btrfs_block_group_flags(&bg
) &
9634 BTRFS_BLOCK_GROUP_TYPE_MASK
;
9636 if (flags
!= (em
->map_lookup
->type
&
9637 BTRFS_BLOCK_GROUP_TYPE_MASK
)) {
9639 "block group %llu len %llu type flags 0x%llx mismatch with chunk type flags 0x%llx",
9641 found_key
.offset
, flags
,
9642 (BTRFS_BLOCK_GROUP_TYPE_MASK
&
9643 em
->map_lookup
->type
));
9649 free_extent_map(em
);
9658 void btrfs_put_block_group_cache(struct btrfs_fs_info
*info
)
9660 struct btrfs_block_group_cache
*block_group
;
9664 struct inode
*inode
;
9666 block_group
= btrfs_lookup_first_block_group(info
, last
);
9667 while (block_group
) {
9668 wait_block_group_cache_done(block_group
);
9669 spin_lock(&block_group
->lock
);
9670 if (block_group
->iref
)
9672 spin_unlock(&block_group
->lock
);
9673 block_group
= next_block_group(info
, block_group
);
9682 inode
= block_group
->inode
;
9683 block_group
->iref
= 0;
9684 block_group
->inode
= NULL
;
9685 spin_unlock(&block_group
->lock
);
9686 ASSERT(block_group
->io_ctl
.inode
== NULL
);
9688 last
= block_group
->key
.objectid
+ block_group
->key
.offset
;
9689 btrfs_put_block_group(block_group
);
9694 * Must be called only after stopping all workers, since we could have block
9695 * group caching kthreads running, and therefore they could race with us if we
9696 * freed the block groups before stopping them.
9698 int btrfs_free_block_groups(struct btrfs_fs_info
*info
)
9700 struct btrfs_block_group_cache
*block_group
;
9701 struct btrfs_space_info
*space_info
;
9702 struct btrfs_caching_control
*caching_ctl
;
9705 down_write(&info
->commit_root_sem
);
9706 while (!list_empty(&info
->caching_block_groups
)) {
9707 caching_ctl
= list_entry(info
->caching_block_groups
.next
,
9708 struct btrfs_caching_control
, list
);
9709 list_del(&caching_ctl
->list
);
9710 put_caching_control(caching_ctl
);
9712 up_write(&info
->commit_root_sem
);
9714 spin_lock(&info
->unused_bgs_lock
);
9715 while (!list_empty(&info
->unused_bgs
)) {
9716 block_group
= list_first_entry(&info
->unused_bgs
,
9717 struct btrfs_block_group_cache
,
9719 list_del_init(&block_group
->bg_list
);
9720 btrfs_put_block_group(block_group
);
9722 spin_unlock(&info
->unused_bgs_lock
);
9724 spin_lock(&info
->block_group_cache_lock
);
9725 while ((n
= rb_last(&info
->block_group_cache_tree
)) != NULL
) {
9726 block_group
= rb_entry(n
, struct btrfs_block_group_cache
,
9728 rb_erase(&block_group
->cache_node
,
9729 &info
->block_group_cache_tree
);
9730 RB_CLEAR_NODE(&block_group
->cache_node
);
9731 spin_unlock(&info
->block_group_cache_lock
);
9733 down_write(&block_group
->space_info
->groups_sem
);
9734 list_del(&block_group
->list
);
9735 up_write(&block_group
->space_info
->groups_sem
);
9738 * We haven't cached this block group, which means we could
9739 * possibly have excluded extents on this block group.
9741 if (block_group
->cached
== BTRFS_CACHE_NO
||
9742 block_group
->cached
== BTRFS_CACHE_ERROR
)
9743 free_excluded_extents(block_group
);
9745 btrfs_remove_free_space_cache(block_group
);
9746 ASSERT(block_group
->cached
!= BTRFS_CACHE_STARTED
);
9747 ASSERT(list_empty(&block_group
->dirty_list
));
9748 ASSERT(list_empty(&block_group
->io_list
));
9749 ASSERT(list_empty(&block_group
->bg_list
));
9750 ASSERT(atomic_read(&block_group
->count
) == 1);
9751 btrfs_put_block_group(block_group
);
9753 spin_lock(&info
->block_group_cache_lock
);
9755 spin_unlock(&info
->block_group_cache_lock
);
9757 /* now that all the block groups are freed, go through and
9758 * free all the space_info structs. This is only called during
9759 * the final stages of unmount, and so we know nobody is
9760 * using them. We call synchronize_rcu() once before we start,
9761 * just to be on the safe side.
9765 release_global_block_rsv(info
);
9767 while (!list_empty(&info
->space_info
)) {
9770 space_info
= list_entry(info
->space_info
.next
,
9771 struct btrfs_space_info
,
9775 * Do not hide this behind enospc_debug, this is actually
9776 * important and indicates a real bug if this happens.
9778 if (WARN_ON(space_info
->bytes_pinned
> 0 ||
9779 space_info
->bytes_reserved
> 0 ||
9780 space_info
->bytes_may_use
> 0))
9781 dump_space_info(info
, space_info
, 0, 0);
9782 list_del(&space_info
->list
);
9783 for (i
= 0; i
< BTRFS_NR_RAID_TYPES
; i
++) {
9784 struct kobject
*kobj
;
9785 kobj
= space_info
->block_group_kobjs
[i
];
9786 space_info
->block_group_kobjs
[i
] = NULL
;
9792 kobject_del(&space_info
->kobj
);
9793 kobject_put(&space_info
->kobj
);
9798 /* link_block_group will queue up kobjects to add when we're reclaim-safe */
9799 void btrfs_add_raid_kobjects(struct btrfs_fs_info
*fs_info
)
9801 struct btrfs_space_info
*space_info
;
9802 struct raid_kobject
*rkobj
;
9807 spin_lock(&fs_info
->pending_raid_kobjs_lock
);
9808 list_splice_init(&fs_info
->pending_raid_kobjs
, &list
);
9809 spin_unlock(&fs_info
->pending_raid_kobjs_lock
);
9811 list_for_each_entry(rkobj
, &list
, list
) {
9812 space_info
= __find_space_info(fs_info
, rkobj
->flags
);
9813 index
= btrfs_bg_flags_to_raid_index(rkobj
->flags
);
9815 ret
= kobject_add(&rkobj
->kobj
, &space_info
->kobj
,
9816 "%s", get_raid_name(index
));
9818 kobject_put(&rkobj
->kobj
);
9824 "failed to add kobject for block cache, ignoring");
9827 static void link_block_group(struct btrfs_block_group_cache
*cache
)
9829 struct btrfs_space_info
*space_info
= cache
->space_info
;
9830 struct btrfs_fs_info
*fs_info
= cache
->fs_info
;
9831 int index
= btrfs_bg_flags_to_raid_index(cache
->flags
);
9834 down_write(&space_info
->groups_sem
);
9835 if (list_empty(&space_info
->block_groups
[index
]))
9837 list_add_tail(&cache
->list
, &space_info
->block_groups
[index
]);
9838 up_write(&space_info
->groups_sem
);
9841 struct raid_kobject
*rkobj
= kzalloc(sizeof(*rkobj
), GFP_NOFS
);
9843 btrfs_warn(cache
->fs_info
,
9844 "couldn't alloc memory for raid level kobject");
9847 rkobj
->flags
= cache
->flags
;
9848 kobject_init(&rkobj
->kobj
, &btrfs_raid_ktype
);
9850 spin_lock(&fs_info
->pending_raid_kobjs_lock
);
9851 list_add_tail(&rkobj
->list
, &fs_info
->pending_raid_kobjs
);
9852 spin_unlock(&fs_info
->pending_raid_kobjs_lock
);
9853 space_info
->block_group_kobjs
[index
] = &rkobj
->kobj
;
9857 static struct btrfs_block_group_cache
*
9858 btrfs_create_block_group_cache(struct btrfs_fs_info
*fs_info
,
9859 u64 start
, u64 size
)
9861 struct btrfs_block_group_cache
*cache
;
9863 cache
= kzalloc(sizeof(*cache
), GFP_NOFS
);
9867 cache
->free_space_ctl
= kzalloc(sizeof(*cache
->free_space_ctl
),
9869 if (!cache
->free_space_ctl
) {
9874 cache
->key
.objectid
= start
;
9875 cache
->key
.offset
= size
;
9876 cache
->key
.type
= BTRFS_BLOCK_GROUP_ITEM_KEY
;
9878 cache
->fs_info
= fs_info
;
9879 cache
->full_stripe_len
= btrfs_full_stripe_len(fs_info
, start
);
9880 set_free_space_tree_thresholds(cache
);
9882 atomic_set(&cache
->count
, 1);
9883 spin_lock_init(&cache
->lock
);
9884 init_rwsem(&cache
->data_rwsem
);
9885 INIT_LIST_HEAD(&cache
->list
);
9886 INIT_LIST_HEAD(&cache
->cluster_list
);
9887 INIT_LIST_HEAD(&cache
->bg_list
);
9888 INIT_LIST_HEAD(&cache
->ro_list
);
9889 INIT_LIST_HEAD(&cache
->dirty_list
);
9890 INIT_LIST_HEAD(&cache
->io_list
);
9891 btrfs_init_free_space_ctl(cache
);
9892 atomic_set(&cache
->trimming
, 0);
9893 mutex_init(&cache
->free_space_lock
);
9894 btrfs_init_full_stripe_locks_tree(&cache
->full_stripe_locks_root
);
9901 * Iterate all chunks and verify that each of them has the corresponding block
9904 static int check_chunk_block_group_mappings(struct btrfs_fs_info
*fs_info
)
9906 struct btrfs_mapping_tree
*map_tree
= &fs_info
->mapping_tree
;
9907 struct extent_map
*em
;
9908 struct btrfs_block_group_cache
*bg
;
9913 read_lock(&map_tree
->map_tree
.lock
);
9915 * lookup_extent_mapping will return the first extent map
9916 * intersecting the range, so setting @len to 1 is enough to
9917 * get the first chunk.
9919 em
= lookup_extent_mapping(&map_tree
->map_tree
, start
, 1);
9920 read_unlock(&map_tree
->map_tree
.lock
);
9924 bg
= btrfs_lookup_block_group(fs_info
, em
->start
);
9927 "chunk start=%llu len=%llu doesn't have corresponding block group",
9928 em
->start
, em
->len
);
9930 free_extent_map(em
);
9933 if (bg
->key
.objectid
!= em
->start
||
9934 bg
->key
.offset
!= em
->len
||
9935 (bg
->flags
& BTRFS_BLOCK_GROUP_TYPE_MASK
) !=
9936 (em
->map_lookup
->type
& BTRFS_BLOCK_GROUP_TYPE_MASK
)) {
9938 "chunk start=%llu len=%llu flags=0x%llx doesn't match block group start=%llu len=%llu flags=0x%llx",
9940 em
->map_lookup
->type
& BTRFS_BLOCK_GROUP_TYPE_MASK
,
9941 bg
->key
.objectid
, bg
->key
.offset
,
9942 bg
->flags
& BTRFS_BLOCK_GROUP_TYPE_MASK
);
9944 free_extent_map(em
);
9945 btrfs_put_block_group(bg
);
9948 start
= em
->start
+ em
->len
;
9949 free_extent_map(em
);
9950 btrfs_put_block_group(bg
);
9955 int btrfs_read_block_groups(struct btrfs_fs_info
*info
)
9957 struct btrfs_path
*path
;
9959 struct btrfs_block_group_cache
*cache
;
9960 struct btrfs_space_info
*space_info
;
9961 struct btrfs_key key
;
9962 struct btrfs_key found_key
;
9963 struct extent_buffer
*leaf
;
9969 feature
= btrfs_super_incompat_flags(info
->super_copy
);
9970 mixed
= !!(feature
& BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS
);
9974 key
.type
= BTRFS_BLOCK_GROUP_ITEM_KEY
;
9975 path
= btrfs_alloc_path();
9978 path
->reada
= READA_FORWARD
;
9980 cache_gen
= btrfs_super_cache_generation(info
->super_copy
);
9981 if (btrfs_test_opt(info
, SPACE_CACHE
) &&
9982 btrfs_super_generation(info
->super_copy
) != cache_gen
)
9984 if (btrfs_test_opt(info
, CLEAR_CACHE
))
9988 ret
= find_first_block_group(info
, path
, &key
);
9994 leaf
= path
->nodes
[0];
9995 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
9997 cache
= btrfs_create_block_group_cache(info
, found_key
.objectid
,
10006 * When we mount with old space cache, we need to
10007 * set BTRFS_DC_CLEAR and set dirty flag.
10009 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
10010 * truncate the old free space cache inode and
10012 * b) Setting 'dirty flag' makes sure that we flush
10013 * the new space cache info onto disk.
10015 if (btrfs_test_opt(info
, SPACE_CACHE
))
10016 cache
->disk_cache_state
= BTRFS_DC_CLEAR
;
10019 read_extent_buffer(leaf
, &cache
->item
,
10020 btrfs_item_ptr_offset(leaf
, path
->slots
[0]),
10021 sizeof(cache
->item
));
10022 cache
->flags
= btrfs_block_group_flags(&cache
->item
);
10024 ((cache
->flags
& BTRFS_BLOCK_GROUP_METADATA
) &&
10025 (cache
->flags
& BTRFS_BLOCK_GROUP_DATA
))) {
10027 "bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups",
10028 cache
->key
.objectid
);
10033 key
.objectid
= found_key
.objectid
+ found_key
.offset
;
10034 btrfs_release_path(path
);
10037 * We need to exclude the super stripes now so that the space
10038 * info has super bytes accounted for, otherwise we'll think
10039 * we have more space than we actually do.
10041 ret
= exclude_super_stripes(cache
);
10044 * We may have excluded something, so call this just in
10047 free_excluded_extents(cache
);
10048 btrfs_put_block_group(cache
);
10053 * check for two cases, either we are full, and therefore
10054 * don't need to bother with the caching work since we won't
10055 * find any space, or we are empty, and we can just add all
10056 * the space in and be done with it. This saves us _alot_ of
10057 * time, particularly in the full case.
10059 if (found_key
.offset
== btrfs_block_group_used(&cache
->item
)) {
10060 cache
->last_byte_to_unpin
= (u64
)-1;
10061 cache
->cached
= BTRFS_CACHE_FINISHED
;
10062 free_excluded_extents(cache
);
10063 } else if (btrfs_block_group_used(&cache
->item
) == 0) {
10064 cache
->last_byte_to_unpin
= (u64
)-1;
10065 cache
->cached
= BTRFS_CACHE_FINISHED
;
10066 add_new_free_space(cache
, found_key
.objectid
,
10067 found_key
.objectid
+
10069 free_excluded_extents(cache
);
10072 ret
= btrfs_add_block_group_cache(info
, cache
);
10074 btrfs_remove_free_space_cache(cache
);
10075 btrfs_put_block_group(cache
);
10079 trace_btrfs_add_block_group(info
, cache
, 0);
10080 update_space_info(info
, cache
->flags
, found_key
.offset
,
10081 btrfs_block_group_used(&cache
->item
),
10082 cache
->bytes_super
, &space_info
);
10084 cache
->space_info
= space_info
;
10086 link_block_group(cache
);
10088 set_avail_alloc_bits(info
, cache
->flags
);
10089 if (btrfs_chunk_readonly(info
, cache
->key
.objectid
)) {
10090 inc_block_group_ro(cache
, 1);
10091 } else if (btrfs_block_group_used(&cache
->item
) == 0) {
10092 ASSERT(list_empty(&cache
->bg_list
));
10093 btrfs_mark_bg_unused(cache
);
10097 list_for_each_entry_rcu(space_info
, &info
->space_info
, list
) {
10098 if (!(get_alloc_profile(info
, space_info
->flags
) &
10099 (BTRFS_BLOCK_GROUP_RAID10
|
10100 BTRFS_BLOCK_GROUP_RAID1
|
10101 BTRFS_BLOCK_GROUP_RAID5
|
10102 BTRFS_BLOCK_GROUP_RAID6
|
10103 BTRFS_BLOCK_GROUP_DUP
)))
10106 * avoid allocating from un-mirrored block group if there are
10107 * mirrored block groups.
10109 list_for_each_entry(cache
,
10110 &space_info
->block_groups
[BTRFS_RAID_RAID0
],
10112 inc_block_group_ro(cache
, 1);
10113 list_for_each_entry(cache
,
10114 &space_info
->block_groups
[BTRFS_RAID_SINGLE
],
10116 inc_block_group_ro(cache
, 1);
10119 btrfs_add_raid_kobjects(info
);
10120 init_global_block_rsv(info
);
10121 ret
= check_chunk_block_group_mappings(info
);
10123 btrfs_free_path(path
);
10127 void btrfs_create_pending_block_groups(struct btrfs_trans_handle
*trans
)
10129 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
10130 struct btrfs_block_group_cache
*block_group
;
10131 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
10132 struct btrfs_block_group_item item
;
10133 struct btrfs_key key
;
10135 bool can_flush_pending_bgs
= trans
->can_flush_pending_bgs
;
10137 trans
->can_flush_pending_bgs
= false;
10138 while (!list_empty(&trans
->new_bgs
)) {
10139 block_group
= list_first_entry(&trans
->new_bgs
,
10140 struct btrfs_block_group_cache
,
10145 spin_lock(&block_group
->lock
);
10146 memcpy(&item
, &block_group
->item
, sizeof(item
));
10147 memcpy(&key
, &block_group
->key
, sizeof(key
));
10148 spin_unlock(&block_group
->lock
);
10150 ret
= btrfs_insert_item(trans
, extent_root
, &key
, &item
,
10153 btrfs_abort_transaction(trans
, ret
);
10154 ret
= btrfs_finish_chunk_alloc(trans
, key
.objectid
, key
.offset
);
10156 btrfs_abort_transaction(trans
, ret
);
10157 add_block_group_free_space(trans
, block_group
);
10158 /* already aborted the transaction if it failed. */
10160 list_del_init(&block_group
->bg_list
);
10162 trans
->can_flush_pending_bgs
= can_flush_pending_bgs
;
10165 int btrfs_make_block_group(struct btrfs_trans_handle
*trans
, u64 bytes_used
,
10166 u64 type
, u64 chunk_offset
, u64 size
)
10168 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
10169 struct btrfs_block_group_cache
*cache
;
10172 btrfs_set_log_full_commit(fs_info
, trans
);
10174 cache
= btrfs_create_block_group_cache(fs_info
, chunk_offset
, size
);
10178 btrfs_set_block_group_used(&cache
->item
, bytes_used
);
10179 btrfs_set_block_group_chunk_objectid(&cache
->item
,
10180 BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
10181 btrfs_set_block_group_flags(&cache
->item
, type
);
10183 cache
->flags
= type
;
10184 cache
->last_byte_to_unpin
= (u64
)-1;
10185 cache
->cached
= BTRFS_CACHE_FINISHED
;
10186 cache
->needs_free_space
= 1;
10187 ret
= exclude_super_stripes(cache
);
10190 * We may have excluded something, so call this just in
10193 free_excluded_extents(cache
);
10194 btrfs_put_block_group(cache
);
10198 add_new_free_space(cache
, chunk_offset
, chunk_offset
+ size
);
10200 free_excluded_extents(cache
);
10202 #ifdef CONFIG_BTRFS_DEBUG
10203 if (btrfs_should_fragment_free_space(cache
)) {
10204 u64 new_bytes_used
= size
- bytes_used
;
10206 bytes_used
+= new_bytes_used
>> 1;
10207 fragment_free_space(cache
);
10211 * Ensure the corresponding space_info object is created and
10212 * assigned to our block group. We want our bg to be added to the rbtree
10213 * with its ->space_info set.
10215 cache
->space_info
= __find_space_info(fs_info
, cache
->flags
);
10216 ASSERT(cache
->space_info
);
10218 ret
= btrfs_add_block_group_cache(fs_info
, cache
);
10220 btrfs_remove_free_space_cache(cache
);
10221 btrfs_put_block_group(cache
);
10226 * Now that our block group has its ->space_info set and is inserted in
10227 * the rbtree, update the space info's counters.
10229 trace_btrfs_add_block_group(fs_info
, cache
, 1);
10230 update_space_info(fs_info
, cache
->flags
, size
, bytes_used
,
10231 cache
->bytes_super
, &cache
->space_info
);
10232 update_global_block_rsv(fs_info
);
10234 link_block_group(cache
);
10236 list_add_tail(&cache
->bg_list
, &trans
->new_bgs
);
10238 set_avail_alloc_bits(fs_info
, type
);
10242 static void clear_avail_alloc_bits(struct btrfs_fs_info
*fs_info
, u64 flags
)
10244 u64 extra_flags
= chunk_to_extended(flags
) &
10245 BTRFS_EXTENDED_PROFILE_MASK
;
10247 write_seqlock(&fs_info
->profiles_lock
);
10248 if (flags
& BTRFS_BLOCK_GROUP_DATA
)
10249 fs_info
->avail_data_alloc_bits
&= ~extra_flags
;
10250 if (flags
& BTRFS_BLOCK_GROUP_METADATA
)
10251 fs_info
->avail_metadata_alloc_bits
&= ~extra_flags
;
10252 if (flags
& BTRFS_BLOCK_GROUP_SYSTEM
)
10253 fs_info
->avail_system_alloc_bits
&= ~extra_flags
;
10254 write_sequnlock(&fs_info
->profiles_lock
);
10257 int btrfs_remove_block_group(struct btrfs_trans_handle
*trans
,
10258 u64 group_start
, struct extent_map
*em
)
10260 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
10261 struct btrfs_root
*root
= fs_info
->extent_root
;
10262 struct btrfs_path
*path
;
10263 struct btrfs_block_group_cache
*block_group
;
10264 struct btrfs_free_cluster
*cluster
;
10265 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
10266 struct btrfs_key key
;
10267 struct inode
*inode
;
10268 struct kobject
*kobj
= NULL
;
10272 struct btrfs_caching_control
*caching_ctl
= NULL
;
10275 block_group
= btrfs_lookup_block_group(fs_info
, group_start
);
10276 BUG_ON(!block_group
);
10277 BUG_ON(!block_group
->ro
);
10279 trace_btrfs_remove_block_group(block_group
);
10281 * Free the reserved super bytes from this block group before
10284 free_excluded_extents(block_group
);
10285 btrfs_free_ref_tree_range(fs_info
, block_group
->key
.objectid
,
10286 block_group
->key
.offset
);
10288 memcpy(&key
, &block_group
->key
, sizeof(key
));
10289 index
= btrfs_bg_flags_to_raid_index(block_group
->flags
);
10290 factor
= btrfs_bg_type_to_factor(block_group
->flags
);
10292 /* make sure this block group isn't part of an allocation cluster */
10293 cluster
= &fs_info
->data_alloc_cluster
;
10294 spin_lock(&cluster
->refill_lock
);
10295 btrfs_return_cluster_to_free_space(block_group
, cluster
);
10296 spin_unlock(&cluster
->refill_lock
);
10299 * make sure this block group isn't part of a metadata
10300 * allocation cluster
10302 cluster
= &fs_info
->meta_alloc_cluster
;
10303 spin_lock(&cluster
->refill_lock
);
10304 btrfs_return_cluster_to_free_space(block_group
, cluster
);
10305 spin_unlock(&cluster
->refill_lock
);
10307 path
= btrfs_alloc_path();
10314 * get the inode first so any iput calls done for the io_list
10315 * aren't the final iput (no unlinks allowed now)
10317 inode
= lookup_free_space_inode(fs_info
, block_group
, path
);
10319 mutex_lock(&trans
->transaction
->cache_write_mutex
);
10321 * make sure our free spache cache IO is done before remove the
10324 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
10325 if (!list_empty(&block_group
->io_list
)) {
10326 list_del_init(&block_group
->io_list
);
10328 WARN_ON(!IS_ERR(inode
) && inode
!= block_group
->io_ctl
.inode
);
10330 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
10331 btrfs_wait_cache_io(trans
, block_group
, path
);
10332 btrfs_put_block_group(block_group
);
10333 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
10336 if (!list_empty(&block_group
->dirty_list
)) {
10337 list_del_init(&block_group
->dirty_list
);
10338 btrfs_put_block_group(block_group
);
10340 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
10341 mutex_unlock(&trans
->transaction
->cache_write_mutex
);
10343 if (!IS_ERR(inode
)) {
10344 ret
= btrfs_orphan_add(trans
, BTRFS_I(inode
));
10346 btrfs_add_delayed_iput(inode
);
10349 clear_nlink(inode
);
10350 /* One for the block groups ref */
10351 spin_lock(&block_group
->lock
);
10352 if (block_group
->iref
) {
10353 block_group
->iref
= 0;
10354 block_group
->inode
= NULL
;
10355 spin_unlock(&block_group
->lock
);
10358 spin_unlock(&block_group
->lock
);
10360 /* One for our lookup ref */
10361 btrfs_add_delayed_iput(inode
);
10364 key
.objectid
= BTRFS_FREE_SPACE_OBJECTID
;
10365 key
.offset
= block_group
->key
.objectid
;
10368 ret
= btrfs_search_slot(trans
, tree_root
, &key
, path
, -1, 1);
10372 btrfs_release_path(path
);
10374 ret
= btrfs_del_item(trans
, tree_root
, path
);
10377 btrfs_release_path(path
);
10380 spin_lock(&fs_info
->block_group_cache_lock
);
10381 rb_erase(&block_group
->cache_node
,
10382 &fs_info
->block_group_cache_tree
);
10383 RB_CLEAR_NODE(&block_group
->cache_node
);
10385 if (fs_info
->first_logical_byte
== block_group
->key
.objectid
)
10386 fs_info
->first_logical_byte
= (u64
)-1;
10387 spin_unlock(&fs_info
->block_group_cache_lock
);
10389 down_write(&block_group
->space_info
->groups_sem
);
10391 * we must use list_del_init so people can check to see if they
10392 * are still on the list after taking the semaphore
10394 list_del_init(&block_group
->list
);
10395 if (list_empty(&block_group
->space_info
->block_groups
[index
])) {
10396 kobj
= block_group
->space_info
->block_group_kobjs
[index
];
10397 block_group
->space_info
->block_group_kobjs
[index
] = NULL
;
10398 clear_avail_alloc_bits(fs_info
, block_group
->flags
);
10400 up_write(&block_group
->space_info
->groups_sem
);
10406 if (block_group
->has_caching_ctl
)
10407 caching_ctl
= get_caching_control(block_group
);
10408 if (block_group
->cached
== BTRFS_CACHE_STARTED
)
10409 wait_block_group_cache_done(block_group
);
10410 if (block_group
->has_caching_ctl
) {
10411 down_write(&fs_info
->commit_root_sem
);
10412 if (!caching_ctl
) {
10413 struct btrfs_caching_control
*ctl
;
10415 list_for_each_entry(ctl
,
10416 &fs_info
->caching_block_groups
, list
)
10417 if (ctl
->block_group
== block_group
) {
10419 refcount_inc(&caching_ctl
->count
);
10424 list_del_init(&caching_ctl
->list
);
10425 up_write(&fs_info
->commit_root_sem
);
10427 /* Once for the caching bgs list and once for us. */
10428 put_caching_control(caching_ctl
);
10429 put_caching_control(caching_ctl
);
10433 spin_lock(&trans
->transaction
->dirty_bgs_lock
);
10434 if (!list_empty(&block_group
->dirty_list
)) {
10437 if (!list_empty(&block_group
->io_list
)) {
10440 spin_unlock(&trans
->transaction
->dirty_bgs_lock
);
10441 btrfs_remove_free_space_cache(block_group
);
10443 spin_lock(&block_group
->space_info
->lock
);
10444 list_del_init(&block_group
->ro_list
);
10446 if (btrfs_test_opt(fs_info
, ENOSPC_DEBUG
)) {
10447 WARN_ON(block_group
->space_info
->total_bytes
10448 < block_group
->key
.offset
);
10449 WARN_ON(block_group
->space_info
->bytes_readonly
10450 < block_group
->key
.offset
);
10451 WARN_ON(block_group
->space_info
->disk_total
10452 < block_group
->key
.offset
* factor
);
10454 block_group
->space_info
->total_bytes
-= block_group
->key
.offset
;
10455 block_group
->space_info
->bytes_readonly
-= block_group
->key
.offset
;
10456 block_group
->space_info
->disk_total
-= block_group
->key
.offset
* factor
;
10458 spin_unlock(&block_group
->space_info
->lock
);
10460 memcpy(&key
, &block_group
->key
, sizeof(key
));
10462 mutex_lock(&fs_info
->chunk_mutex
);
10463 if (!list_empty(&em
->list
)) {
10464 /* We're in the transaction->pending_chunks list. */
10465 free_extent_map(em
);
10467 spin_lock(&block_group
->lock
);
10468 block_group
->removed
= 1;
10470 * At this point trimming can't start on this block group, because we
10471 * removed the block group from the tree fs_info->block_group_cache_tree
10472 * so no one can't find it anymore and even if someone already got this
10473 * block group before we removed it from the rbtree, they have already
10474 * incremented block_group->trimming - if they didn't, they won't find
10475 * any free space entries because we already removed them all when we
10476 * called btrfs_remove_free_space_cache().
10478 * And we must not remove the extent map from the fs_info->mapping_tree
10479 * to prevent the same logical address range and physical device space
10480 * ranges from being reused for a new block group. This is because our
10481 * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is
10482 * completely transactionless, so while it is trimming a range the
10483 * currently running transaction might finish and a new one start,
10484 * allowing for new block groups to be created that can reuse the same
10485 * physical device locations unless we take this special care.
10487 * There may also be an implicit trim operation if the file system
10488 * is mounted with -odiscard. The same protections must remain
10489 * in place until the extents have been discarded completely when
10490 * the transaction commit has completed.
10492 remove_em
= (atomic_read(&block_group
->trimming
) == 0);
10494 * Make sure a trimmer task always sees the em in the pinned_chunks list
10495 * if it sees block_group->removed == 1 (needs to lock block_group->lock
10496 * before checking block_group->removed).
10500 * Our em might be in trans->transaction->pending_chunks which
10501 * is protected by fs_info->chunk_mutex ([lock|unlock]_chunks),
10502 * and so is the fs_info->pinned_chunks list.
10504 * So at this point we must be holding the chunk_mutex to avoid
10505 * any races with chunk allocation (more specifically at
10506 * volumes.c:contains_pending_extent()), to ensure it always
10507 * sees the em, either in the pending_chunks list or in the
10508 * pinned_chunks list.
10510 list_move_tail(&em
->list
, &fs_info
->pinned_chunks
);
10512 spin_unlock(&block_group
->lock
);
10515 struct extent_map_tree
*em_tree
;
10517 em_tree
= &fs_info
->mapping_tree
.map_tree
;
10518 write_lock(&em_tree
->lock
);
10520 * The em might be in the pending_chunks list, so make sure the
10521 * chunk mutex is locked, since remove_extent_mapping() will
10522 * delete us from that list.
10524 remove_extent_mapping(em_tree
, em
);
10525 write_unlock(&em_tree
->lock
);
10526 /* once for the tree */
10527 free_extent_map(em
);
10530 mutex_unlock(&fs_info
->chunk_mutex
);
10532 ret
= remove_block_group_free_space(trans
, block_group
);
10536 btrfs_put_block_group(block_group
);
10537 btrfs_put_block_group(block_group
);
10539 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
10545 ret
= btrfs_del_item(trans
, root
, path
);
10547 btrfs_free_path(path
);
10551 struct btrfs_trans_handle
*
10552 btrfs_start_trans_remove_block_group(struct btrfs_fs_info
*fs_info
,
10553 const u64 chunk_offset
)
10555 struct extent_map_tree
*em_tree
= &fs_info
->mapping_tree
.map_tree
;
10556 struct extent_map
*em
;
10557 struct map_lookup
*map
;
10558 unsigned int num_items
;
10560 read_lock(&em_tree
->lock
);
10561 em
= lookup_extent_mapping(em_tree
, chunk_offset
, 1);
10562 read_unlock(&em_tree
->lock
);
10563 ASSERT(em
&& em
->start
== chunk_offset
);
10566 * We need to reserve 3 + N units from the metadata space info in order
10567 * to remove a block group (done at btrfs_remove_chunk() and at
10568 * btrfs_remove_block_group()), which are used for:
10570 * 1 unit for adding the free space inode's orphan (located in the tree
10572 * 1 unit for deleting the block group item (located in the extent
10574 * 1 unit for deleting the free space item (located in tree of tree
10576 * N units for deleting N device extent items corresponding to each
10577 * stripe (located in the device tree).
10579 * In order to remove a block group we also need to reserve units in the
10580 * system space info in order to update the chunk tree (update one or
10581 * more device items and remove one chunk item), but this is done at
10582 * btrfs_remove_chunk() through a call to check_system_chunk().
10584 map
= em
->map_lookup
;
10585 num_items
= 3 + map
->num_stripes
;
10586 free_extent_map(em
);
10588 return btrfs_start_transaction_fallback_global_rsv(fs_info
->extent_root
,
10593 * Process the unused_bgs list and remove any that don't have any allocated
10594 * space inside of them.
10596 void btrfs_delete_unused_bgs(struct btrfs_fs_info
*fs_info
)
10598 struct btrfs_block_group_cache
*block_group
;
10599 struct btrfs_space_info
*space_info
;
10600 struct btrfs_trans_handle
*trans
;
10603 if (!test_bit(BTRFS_FS_OPEN
, &fs_info
->flags
))
10606 spin_lock(&fs_info
->unused_bgs_lock
);
10607 while (!list_empty(&fs_info
->unused_bgs
)) {
10611 block_group
= list_first_entry(&fs_info
->unused_bgs
,
10612 struct btrfs_block_group_cache
,
10614 list_del_init(&block_group
->bg_list
);
10616 space_info
= block_group
->space_info
;
10618 if (ret
|| btrfs_mixed_space_info(space_info
)) {
10619 btrfs_put_block_group(block_group
);
10622 spin_unlock(&fs_info
->unused_bgs_lock
);
10624 mutex_lock(&fs_info
->delete_unused_bgs_mutex
);
10626 /* Don't want to race with allocators so take the groups_sem */
10627 down_write(&space_info
->groups_sem
);
10628 spin_lock(&block_group
->lock
);
10629 if (block_group
->reserved
|| block_group
->pinned
||
10630 btrfs_block_group_used(&block_group
->item
) ||
10632 list_is_singular(&block_group
->list
)) {
10634 * We want to bail if we made new allocations or have
10635 * outstanding allocations in this block group. We do
10636 * the ro check in case balance is currently acting on
10637 * this block group.
10639 trace_btrfs_skip_unused_block_group(block_group
);
10640 spin_unlock(&block_group
->lock
);
10641 up_write(&space_info
->groups_sem
);
10644 spin_unlock(&block_group
->lock
);
10646 /* We don't want to force the issue, only flip if it's ok. */
10647 ret
= inc_block_group_ro(block_group
, 0);
10648 up_write(&space_info
->groups_sem
);
10655 * Want to do this before we do anything else so we can recover
10656 * properly if we fail to join the transaction.
10658 trans
= btrfs_start_trans_remove_block_group(fs_info
,
10659 block_group
->key
.objectid
);
10660 if (IS_ERR(trans
)) {
10661 btrfs_dec_block_group_ro(block_group
);
10662 ret
= PTR_ERR(trans
);
10667 * We could have pending pinned extents for this block group,
10668 * just delete them, we don't care about them anymore.
10670 start
= block_group
->key
.objectid
;
10671 end
= start
+ block_group
->key
.offset
- 1;
10673 * Hold the unused_bg_unpin_mutex lock to avoid racing with
10674 * btrfs_finish_extent_commit(). If we are at transaction N,
10675 * another task might be running finish_extent_commit() for the
10676 * previous transaction N - 1, and have seen a range belonging
10677 * to the block group in freed_extents[] before we were able to
10678 * clear the whole block group range from freed_extents[]. This
10679 * means that task can lookup for the block group after we
10680 * unpinned it from freed_extents[] and removed it, leading to
10681 * a BUG_ON() at btrfs_unpin_extent_range().
10683 mutex_lock(&fs_info
->unused_bg_unpin_mutex
);
10684 ret
= clear_extent_bits(&fs_info
->freed_extents
[0], start
, end
,
10687 mutex_unlock(&fs_info
->unused_bg_unpin_mutex
);
10688 btrfs_dec_block_group_ro(block_group
);
10691 ret
= clear_extent_bits(&fs_info
->freed_extents
[1], start
, end
,
10694 mutex_unlock(&fs_info
->unused_bg_unpin_mutex
);
10695 btrfs_dec_block_group_ro(block_group
);
10698 mutex_unlock(&fs_info
->unused_bg_unpin_mutex
);
10700 /* Reset pinned so btrfs_put_block_group doesn't complain */
10701 spin_lock(&space_info
->lock
);
10702 spin_lock(&block_group
->lock
);
10704 space_info
->bytes_pinned
-= block_group
->pinned
;
10705 space_info
->bytes_readonly
+= block_group
->pinned
;
10706 percpu_counter_add_batch(&space_info
->total_bytes_pinned
,
10707 -block_group
->pinned
,
10708 BTRFS_TOTAL_BYTES_PINNED_BATCH
);
10709 block_group
->pinned
= 0;
10711 spin_unlock(&block_group
->lock
);
10712 spin_unlock(&space_info
->lock
);
10714 /* DISCARD can flip during remount */
10715 trimming
= btrfs_test_opt(fs_info
, DISCARD
);
10717 /* Implicit trim during transaction commit. */
10719 btrfs_get_block_group_trimming(block_group
);
10722 * Btrfs_remove_chunk will abort the transaction if things go
10725 ret
= btrfs_remove_chunk(trans
, block_group
->key
.objectid
);
10729 btrfs_put_block_group_trimming(block_group
);
10734 * If we're not mounted with -odiscard, we can just forget
10735 * about this block group. Otherwise we'll need to wait
10736 * until transaction commit to do the actual discard.
10739 spin_lock(&fs_info
->unused_bgs_lock
);
10741 * A concurrent scrub might have added us to the list
10742 * fs_info->unused_bgs, so use a list_move operation
10743 * to add the block group to the deleted_bgs list.
10745 list_move(&block_group
->bg_list
,
10746 &trans
->transaction
->deleted_bgs
);
10747 spin_unlock(&fs_info
->unused_bgs_lock
);
10748 btrfs_get_block_group(block_group
);
10751 btrfs_end_transaction(trans
);
10753 mutex_unlock(&fs_info
->delete_unused_bgs_mutex
);
10754 btrfs_put_block_group(block_group
);
10755 spin_lock(&fs_info
->unused_bgs_lock
);
10757 spin_unlock(&fs_info
->unused_bgs_lock
);
10760 int btrfs_init_space_info(struct btrfs_fs_info
*fs_info
)
10762 struct btrfs_super_block
*disk_super
;
10768 disk_super
= fs_info
->super_copy
;
10769 if (!btrfs_super_root(disk_super
))
10772 features
= btrfs_super_incompat_flags(disk_super
);
10773 if (features
& BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS
)
10776 flags
= BTRFS_BLOCK_GROUP_SYSTEM
;
10777 ret
= create_space_info(fs_info
, flags
);
10782 flags
= BTRFS_BLOCK_GROUP_METADATA
| BTRFS_BLOCK_GROUP_DATA
;
10783 ret
= create_space_info(fs_info
, flags
);
10785 flags
= BTRFS_BLOCK_GROUP_METADATA
;
10786 ret
= create_space_info(fs_info
, flags
);
10790 flags
= BTRFS_BLOCK_GROUP_DATA
;
10791 ret
= create_space_info(fs_info
, flags
);
10797 int btrfs_error_unpin_extent_range(struct btrfs_fs_info
*fs_info
,
10798 u64 start
, u64 end
)
10800 return unpin_extent_range(fs_info
, start
, end
, false);
10804 * It used to be that old block groups would be left around forever.
10805 * Iterating over them would be enough to trim unused space. Since we
10806 * now automatically remove them, we also need to iterate over unallocated
10809 * We don't want a transaction for this since the discard may take a
10810 * substantial amount of time. We don't require that a transaction be
10811 * running, but we do need to take a running transaction into account
10812 * to ensure that we're not discarding chunks that were released or
10813 * allocated in the current transaction.
10815 * Holding the chunks lock will prevent other threads from allocating
10816 * or releasing chunks, but it won't prevent a running transaction
10817 * from committing and releasing the memory that the pending chunks
10818 * list head uses. For that, we need to take a reference to the
10819 * transaction and hold the commit root sem. We only need to hold
10820 * it while performing the free space search since we have already
10821 * held back allocations.
10823 static int btrfs_trim_free_extents(struct btrfs_device
*device
,
10824 u64 minlen
, u64
*trimmed
)
10826 u64 start
= 0, len
= 0;
10831 /* Discard not supported = nothing to do. */
10832 if (!blk_queue_discard(bdev_get_queue(device
->bdev
)))
10835 /* Not writeable = nothing to do. */
10836 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE
, &device
->dev_state
))
10839 /* No free space = nothing to do. */
10840 if (device
->total_bytes
<= device
->bytes_used
)
10846 struct btrfs_fs_info
*fs_info
= device
->fs_info
;
10847 struct btrfs_transaction
*trans
;
10850 ret
= mutex_lock_interruptible(&fs_info
->chunk_mutex
);
10854 ret
= down_read_killable(&fs_info
->commit_root_sem
);
10856 mutex_unlock(&fs_info
->chunk_mutex
);
10860 spin_lock(&fs_info
->trans_lock
);
10861 trans
= fs_info
->running_transaction
;
10863 refcount_inc(&trans
->use_count
);
10864 spin_unlock(&fs_info
->trans_lock
);
10867 up_read(&fs_info
->commit_root_sem
);
10869 ret
= find_free_dev_extent_start(trans
, device
, minlen
, start
,
10872 up_read(&fs_info
->commit_root_sem
);
10873 btrfs_put_transaction(trans
);
10877 mutex_unlock(&fs_info
->chunk_mutex
);
10878 if (ret
== -ENOSPC
)
10883 ret
= btrfs_issue_discard(device
->bdev
, start
, len
, &bytes
);
10884 mutex_unlock(&fs_info
->chunk_mutex
);
10892 if (fatal_signal_pending(current
)) {
10893 ret
= -ERESTARTSYS
;
10904 * Trim the whole filesystem by:
10905 * 1) trimming the free space in each block group
10906 * 2) trimming the unallocated space on each device
10908 * This will also continue trimming even if a block group or device encounters
10909 * an error. The return value will be the last error, or 0 if nothing bad
10912 int btrfs_trim_fs(struct btrfs_fs_info
*fs_info
, struct fstrim_range
*range
)
10914 struct btrfs_block_group_cache
*cache
= NULL
;
10915 struct btrfs_device
*device
;
10916 struct list_head
*devices
;
10922 u64 dev_failed
= 0;
10927 cache
= btrfs_lookup_first_block_group(fs_info
, range
->start
);
10928 for (; cache
; cache
= next_block_group(fs_info
, cache
)) {
10929 if (cache
->key
.objectid
>= (range
->start
+ range
->len
)) {
10930 btrfs_put_block_group(cache
);
10934 start
= max(range
->start
, cache
->key
.objectid
);
10935 end
= min(range
->start
+ range
->len
,
10936 cache
->key
.objectid
+ cache
->key
.offset
);
10938 if (end
- start
>= range
->minlen
) {
10939 if (!block_group_cache_done(cache
)) {
10940 ret
= cache_block_group(cache
, 0);
10946 ret
= wait_block_group_cache_done(cache
);
10953 ret
= btrfs_trim_block_group(cache
,
10959 trimmed
+= group_trimmed
;
10969 btrfs_warn(fs_info
,
10970 "failed to trim %llu block group(s), last error %d",
10971 bg_failed
, bg_ret
);
10972 mutex_lock(&fs_info
->fs_devices
->device_list_mutex
);
10973 devices
= &fs_info
->fs_devices
->devices
;
10974 list_for_each_entry(device
, devices
, dev_list
) {
10975 ret
= btrfs_trim_free_extents(device
, range
->minlen
,
10983 trimmed
+= group_trimmed
;
10985 mutex_unlock(&fs_info
->fs_devices
->device_list_mutex
);
10988 btrfs_warn(fs_info
,
10989 "failed to trim %llu device(s), last error %d",
10990 dev_failed
, dev_ret
);
10991 range
->len
= trimmed
;
10998 * btrfs_{start,end}_write_no_snapshotting() are similar to
10999 * mnt_{want,drop}_write(), they are used to prevent some tasks from writing
11000 * data into the page cache through nocow before the subvolume is snapshoted,
11001 * but flush the data into disk after the snapshot creation, or to prevent
11002 * operations while snapshotting is ongoing and that cause the snapshot to be
11003 * inconsistent (writes followed by expanding truncates for example).
11005 void btrfs_end_write_no_snapshotting(struct btrfs_root
*root
)
11007 percpu_counter_dec(&root
->subv_writers
->counter
);
11008 cond_wake_up(&root
->subv_writers
->wait
);
11011 int btrfs_start_write_no_snapshotting(struct btrfs_root
*root
)
11013 if (atomic_read(&root
->will_be_snapshotted
))
11016 percpu_counter_inc(&root
->subv_writers
->counter
);
11018 * Make sure counter is updated before we check for snapshot creation.
11021 if (atomic_read(&root
->will_be_snapshotted
)) {
11022 btrfs_end_write_no_snapshotting(root
);
11028 void btrfs_wait_for_snapshot_creation(struct btrfs_root
*root
)
11033 ret
= btrfs_start_write_no_snapshotting(root
);
11036 wait_var_event(&root
->will_be_snapshotted
,
11037 !atomic_read(&root
->will_be_snapshotted
));
11041 void btrfs_mark_bg_unused(struct btrfs_block_group_cache
*bg
)
11043 struct btrfs_fs_info
*fs_info
= bg
->fs_info
;
11045 spin_lock(&fs_info
->unused_bgs_lock
);
11046 if (list_empty(&bg
->bg_list
)) {
11047 btrfs_get_block_group(bg
);
11048 trace_btrfs_add_unused_block_group(bg
);
11049 list_add_tail(&bg
->bg_list
, &fs_info
->unused_bgs
);
11051 spin_unlock(&fs_info
->unused_bgs_lock
);