2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
18 #include <linux/sched.h>
19 #include <linux/pagemap.h>
20 #include <linux/writeback.h>
21 #include <linux/blkdev.h>
22 #include <linux/sort.h>
23 #include <linux/rcupdate.h>
24 #include <linux/kthread.h>
25 #include <linux/slab.h>
26 #include <linux/ratelimit.h>
31 #include "print-tree.h"
32 #include "transaction.h"
35 #include "free-space-cache.h"
38 #undef SCRAMBLE_DELAYED_REFS
41 * control flags for do_chunk_alloc's force field
42 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
43 * if we really need one.
45 * CHUNK_ALLOC_LIMITED means to only try and allocate one
46 * if we have very few chunks already allocated. This is
47 * used as part of the clustering code to help make sure
48 * we have a good pool of storage to cluster in, without
49 * filling the FS with empty chunks
51 * CHUNK_ALLOC_FORCE means it must try to allocate one
55 CHUNK_ALLOC_NO_FORCE = 0,
56 CHUNK_ALLOC_LIMITED = 1,
57 CHUNK_ALLOC_FORCE = 2,
61 * Control how reservations are dealt with.
63 * RESERVE_FREE - freeing a reservation.
64 * RESERVE_ALLOC - allocating space and we need to update bytes_may_use for
66 * RESERVE_ALLOC_NO_ACCOUNT - allocating space and we should not update
67 * bytes_may_use as the ENOSPC accounting is done elsewhere
72 RESERVE_ALLOC_NO_ACCOUNT = 2,
75 static int update_block_group(struct btrfs_trans_handle *trans,
76 struct btrfs_root *root,
77 u64 bytenr, u64 num_bytes, int alloc);
78 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
79 struct btrfs_root *root,
80 u64 bytenr, u64 num_bytes, u64 parent,
81 u64 root_objectid, u64 owner_objectid,
82 u64 owner_offset, int refs_to_drop,
83 struct btrfs_delayed_extent_op *extra_op);
84 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
85 struct extent_buffer *leaf,
86 struct btrfs_extent_item *ei);
87 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
88 struct btrfs_root *root,
89 u64 parent, u64 root_objectid,
90 u64 flags, u64 owner, u64 offset,
91 struct btrfs_key *ins, int ref_mod);
92 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
93 struct btrfs_root *root,
94 u64 parent, u64 root_objectid,
95 u64 flags, struct btrfs_disk_key *key,
96 int level, struct btrfs_key *ins);
97 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
98 struct btrfs_root *extent_root, u64 flags,
100 static int find_next_key(struct btrfs_path *path, int level,
101 struct btrfs_key *key);
102 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
103 int dump_block_groups);
104 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
105 u64 num_bytes, int reserve);
108 block_group_cache_done(struct btrfs_block_group_cache *cache)
111 return cache->cached == BTRFS_CACHE_FINISHED;
114 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
116 return (cache->flags & bits) == bits;
119 static void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
121 atomic_inc(&cache->count);
124 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
126 if (atomic_dec_and_test(&cache->count)) {
127 WARN_ON(cache->pinned > 0);
128 WARN_ON(cache->reserved > 0);
129 kfree(cache->free_space_ctl);
135 * this adds the block group to the fs_info rb tree for the block group
138 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
139 struct btrfs_block_group_cache *block_group)
142 struct rb_node *parent = NULL;
143 struct btrfs_block_group_cache *cache;
145 spin_lock(&info->block_group_cache_lock);
146 p = &info->block_group_cache_tree.rb_node;
150 cache = rb_entry(parent, struct btrfs_block_group_cache,
152 if (block_group->key.objectid < cache->key.objectid) {
154 } else if (block_group->key.objectid > cache->key.objectid) {
157 spin_unlock(&info->block_group_cache_lock);
162 rb_link_node(&block_group->cache_node, parent, p);
163 rb_insert_color(&block_group->cache_node,
164 &info->block_group_cache_tree);
165 spin_unlock(&info->block_group_cache_lock);
171 * This will return the block group at or after bytenr if contains is 0, else
172 * it will return the block group that contains the bytenr
174 static struct btrfs_block_group_cache *
175 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
178 struct btrfs_block_group_cache *cache, *ret = NULL;
182 spin_lock(&info->block_group_cache_lock);
183 n = info->block_group_cache_tree.rb_node;
186 cache = rb_entry(n, struct btrfs_block_group_cache,
188 end = cache->key.objectid + cache->key.offset - 1;
189 start = cache->key.objectid;
191 if (bytenr < start) {
192 if (!contains && (!ret || start < ret->key.objectid))
195 } else if (bytenr > start) {
196 if (contains && bytenr <= end) {
207 btrfs_get_block_group(ret);
208 spin_unlock(&info->block_group_cache_lock);
213 static int add_excluded_extent(struct btrfs_root *root,
214 u64 start, u64 num_bytes)
216 u64 end = start + num_bytes - 1;
217 set_extent_bits(&root->fs_info->freed_extents[0],
218 start, end, EXTENT_UPTODATE, GFP_NOFS);
219 set_extent_bits(&root->fs_info->freed_extents[1],
220 start, end, EXTENT_UPTODATE, GFP_NOFS);
224 static void free_excluded_extents(struct btrfs_root *root,
225 struct btrfs_block_group_cache *cache)
229 start = cache->key.objectid;
230 end = start + cache->key.offset - 1;
232 clear_extent_bits(&root->fs_info->freed_extents[0],
233 start, end, EXTENT_UPTODATE, GFP_NOFS);
234 clear_extent_bits(&root->fs_info->freed_extents[1],
235 start, end, EXTENT_UPTODATE, GFP_NOFS);
238 static int exclude_super_stripes(struct btrfs_root *root,
239 struct btrfs_block_group_cache *cache)
246 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
247 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
248 cache->bytes_super += stripe_len;
249 ret = add_excluded_extent(root, cache->key.objectid,
251 BUG_ON(ret); /* -ENOMEM */
254 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
255 bytenr = btrfs_sb_offset(i);
256 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
257 cache->key.objectid, bytenr,
258 0, &logical, &nr, &stripe_len);
259 BUG_ON(ret); /* -ENOMEM */
262 cache->bytes_super += stripe_len;
263 ret = add_excluded_extent(root, logical[nr],
265 BUG_ON(ret); /* -ENOMEM */
273 static struct btrfs_caching_control *
274 get_caching_control(struct btrfs_block_group_cache *cache)
276 struct btrfs_caching_control *ctl;
278 spin_lock(&cache->lock);
279 if (cache->cached != BTRFS_CACHE_STARTED) {
280 spin_unlock(&cache->lock);
284 /* We're loading it the fast way, so we don't have a caching_ctl. */
285 if (!cache->caching_ctl) {
286 spin_unlock(&cache->lock);
290 ctl = cache->caching_ctl;
291 atomic_inc(&ctl->count);
292 spin_unlock(&cache->lock);
296 static void put_caching_control(struct btrfs_caching_control *ctl)
298 if (atomic_dec_and_test(&ctl->count))
303 * this is only called by cache_block_group, since we could have freed extents
304 * we need to check the pinned_extents for any extents that can't be used yet
305 * since their free space will be released as soon as the transaction commits.
307 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
308 struct btrfs_fs_info *info, u64 start, u64 end)
310 u64 extent_start, extent_end, size, total_added = 0;
313 while (start < end) {
314 ret = find_first_extent_bit(info->pinned_extents, start,
315 &extent_start, &extent_end,
316 EXTENT_DIRTY | EXTENT_UPTODATE,
321 if (extent_start <= start) {
322 start = extent_end + 1;
323 } else if (extent_start > start && extent_start < end) {
324 size = extent_start - start;
326 ret = btrfs_add_free_space(block_group, start,
328 BUG_ON(ret); /* -ENOMEM or logic error */
329 start = extent_end + 1;
338 ret = btrfs_add_free_space(block_group, start, size);
339 BUG_ON(ret); /* -ENOMEM or logic error */
345 static noinline void caching_thread(struct btrfs_work *work)
347 struct btrfs_block_group_cache *block_group;
348 struct btrfs_fs_info *fs_info;
349 struct btrfs_caching_control *caching_ctl;
350 struct btrfs_root *extent_root;
351 struct btrfs_path *path;
352 struct extent_buffer *leaf;
353 struct btrfs_key key;
359 caching_ctl = container_of(work, struct btrfs_caching_control, work);
360 block_group = caching_ctl->block_group;
361 fs_info = block_group->fs_info;
362 extent_root = fs_info->extent_root;
364 path = btrfs_alloc_path();
368 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
371 * We don't want to deadlock with somebody trying to allocate a new
372 * extent for the extent root while also trying to search the extent
373 * root to add free space. So we skip locking and search the commit
374 * root, since its read-only
376 path->skip_locking = 1;
377 path->search_commit_root = 1;
382 key.type = BTRFS_EXTENT_ITEM_KEY;
384 mutex_lock(&caching_ctl->mutex);
385 /* need to make sure the commit_root doesn't disappear */
386 down_read(&fs_info->extent_commit_sem);
388 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
392 leaf = path->nodes[0];
393 nritems = btrfs_header_nritems(leaf);
396 if (btrfs_fs_closing(fs_info) > 1) {
401 if (path->slots[0] < nritems) {
402 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
404 ret = find_next_key(path, 0, &key);
408 if (need_resched() ||
409 btrfs_next_leaf(extent_root, path)) {
410 caching_ctl->progress = last;
411 btrfs_release_path(path);
412 up_read(&fs_info->extent_commit_sem);
413 mutex_unlock(&caching_ctl->mutex);
417 leaf = path->nodes[0];
418 nritems = btrfs_header_nritems(leaf);
422 if (key.objectid < block_group->key.objectid) {
427 if (key.objectid >= block_group->key.objectid +
428 block_group->key.offset)
431 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
432 total_found += add_new_free_space(block_group,
435 last = key.objectid + key.offset;
437 if (total_found > (1024 * 1024 * 2)) {
439 wake_up(&caching_ctl->wait);
446 total_found += add_new_free_space(block_group, fs_info, last,
447 block_group->key.objectid +
448 block_group->key.offset);
449 caching_ctl->progress = (u64)-1;
451 spin_lock(&block_group->lock);
452 block_group->caching_ctl = NULL;
453 block_group->cached = BTRFS_CACHE_FINISHED;
454 spin_unlock(&block_group->lock);
457 btrfs_free_path(path);
458 up_read(&fs_info->extent_commit_sem);
460 free_excluded_extents(extent_root, block_group);
462 mutex_unlock(&caching_ctl->mutex);
464 wake_up(&caching_ctl->wait);
466 put_caching_control(caching_ctl);
467 btrfs_put_block_group(block_group);
470 static int cache_block_group(struct btrfs_block_group_cache *cache,
471 struct btrfs_trans_handle *trans,
472 struct btrfs_root *root,
476 struct btrfs_fs_info *fs_info = cache->fs_info;
477 struct btrfs_caching_control *caching_ctl;
480 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
484 INIT_LIST_HEAD(&caching_ctl->list);
485 mutex_init(&caching_ctl->mutex);
486 init_waitqueue_head(&caching_ctl->wait);
487 caching_ctl->block_group = cache;
488 caching_ctl->progress = cache->key.objectid;
489 atomic_set(&caching_ctl->count, 1);
490 caching_ctl->work.func = caching_thread;
492 spin_lock(&cache->lock);
494 * This should be a rare occasion, but this could happen I think in the
495 * case where one thread starts to load the space cache info, and then
496 * some other thread starts a transaction commit which tries to do an
497 * allocation while the other thread is still loading the space cache
498 * info. The previous loop should have kept us from choosing this block
499 * group, but if we've moved to the state where we will wait on caching
500 * block groups we need to first check if we're doing a fast load here,
501 * so we can wait for it to finish, otherwise we could end up allocating
502 * from a block group who's cache gets evicted for one reason or
505 while (cache->cached == BTRFS_CACHE_FAST) {
506 struct btrfs_caching_control *ctl;
508 ctl = cache->caching_ctl;
509 atomic_inc(&ctl->count);
510 prepare_to_wait(&ctl->wait, &wait, TASK_UNINTERRUPTIBLE);
511 spin_unlock(&cache->lock);
515 finish_wait(&ctl->wait, &wait);
516 put_caching_control(ctl);
517 spin_lock(&cache->lock);
520 if (cache->cached != BTRFS_CACHE_NO) {
521 spin_unlock(&cache->lock);
525 WARN_ON(cache->caching_ctl);
526 cache->caching_ctl = caching_ctl;
527 cache->cached = BTRFS_CACHE_FAST;
528 spin_unlock(&cache->lock);
531 * We can't do the read from on-disk cache during a commit since we need
532 * to have the normal tree locking. Also if we are currently trying to
533 * allocate blocks for the tree root we can't do the fast caching since
534 * we likely hold important locks.
536 if (fs_info->mount_opt & BTRFS_MOUNT_SPACE_CACHE) {
537 ret = load_free_space_cache(fs_info, cache);
539 spin_lock(&cache->lock);
541 cache->caching_ctl = NULL;
542 cache->cached = BTRFS_CACHE_FINISHED;
543 cache->last_byte_to_unpin = (u64)-1;
545 if (load_cache_only) {
546 cache->caching_ctl = NULL;
547 cache->cached = BTRFS_CACHE_NO;
549 cache->cached = BTRFS_CACHE_STARTED;
552 spin_unlock(&cache->lock);
553 wake_up(&caching_ctl->wait);
555 put_caching_control(caching_ctl);
556 free_excluded_extents(fs_info->extent_root, cache);
561 * We are not going to do the fast caching, set cached to the
562 * appropriate value and wakeup any waiters.
564 spin_lock(&cache->lock);
565 if (load_cache_only) {
566 cache->caching_ctl = NULL;
567 cache->cached = BTRFS_CACHE_NO;
569 cache->cached = BTRFS_CACHE_STARTED;
571 spin_unlock(&cache->lock);
572 wake_up(&caching_ctl->wait);
575 if (load_cache_only) {
576 put_caching_control(caching_ctl);
580 down_write(&fs_info->extent_commit_sem);
581 atomic_inc(&caching_ctl->count);
582 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
583 up_write(&fs_info->extent_commit_sem);
585 btrfs_get_block_group(cache);
587 btrfs_queue_worker(&fs_info->caching_workers, &caching_ctl->work);
593 * return the block group that starts at or after bytenr
595 static struct btrfs_block_group_cache *
596 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
598 struct btrfs_block_group_cache *cache;
600 cache = block_group_cache_tree_search(info, bytenr, 0);
606 * return the block group that contains the given bytenr
608 struct btrfs_block_group_cache *btrfs_lookup_block_group(
609 struct btrfs_fs_info *info,
612 struct btrfs_block_group_cache *cache;
614 cache = block_group_cache_tree_search(info, bytenr, 1);
619 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
622 struct list_head *head = &info->space_info;
623 struct btrfs_space_info *found;
625 flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
628 list_for_each_entry_rcu(found, head, list) {
629 if (found->flags & flags) {
639 * after adding space to the filesystem, we need to clear the full flags
640 * on all the space infos.
642 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
644 struct list_head *head = &info->space_info;
645 struct btrfs_space_info *found;
648 list_for_each_entry_rcu(found, head, list)
653 u64 btrfs_find_block_group(struct btrfs_root *root,
654 u64 search_start, u64 search_hint, int owner)
656 struct btrfs_block_group_cache *cache;
658 u64 last = max(search_hint, search_start);
665 cache = btrfs_lookup_first_block_group(root->fs_info, last);
669 spin_lock(&cache->lock);
670 last = cache->key.objectid + cache->key.offset;
671 used = btrfs_block_group_used(&cache->item);
673 if ((full_search || !cache->ro) &&
674 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
675 if (used + cache->pinned + cache->reserved <
676 div_factor(cache->key.offset, factor)) {
677 group_start = cache->key.objectid;
678 spin_unlock(&cache->lock);
679 btrfs_put_block_group(cache);
683 spin_unlock(&cache->lock);
684 btrfs_put_block_group(cache);
692 if (!full_search && factor < 10) {
702 /* simple helper to search for an existing extent at a given offset */
703 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
706 struct btrfs_key key;
707 struct btrfs_path *path;
709 path = btrfs_alloc_path();
713 key.objectid = start;
715 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
716 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
718 btrfs_free_path(path);
723 * helper function to lookup reference count and flags of extent.
725 * the head node for delayed ref is used to store the sum of all the
726 * reference count modifications queued up in the rbtree. the head
727 * node may also store the extent flags to set. This way you can check
728 * to see what the reference count and extent flags would be if all of
729 * the delayed refs are not processed.
731 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
732 struct btrfs_root *root, u64 bytenr,
733 u64 num_bytes, u64 *refs, u64 *flags)
735 struct btrfs_delayed_ref_head *head;
736 struct btrfs_delayed_ref_root *delayed_refs;
737 struct btrfs_path *path;
738 struct btrfs_extent_item *ei;
739 struct extent_buffer *leaf;
740 struct btrfs_key key;
746 path = btrfs_alloc_path();
750 key.objectid = bytenr;
751 key.type = BTRFS_EXTENT_ITEM_KEY;
752 key.offset = num_bytes;
754 path->skip_locking = 1;
755 path->search_commit_root = 1;
758 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
764 leaf = path->nodes[0];
765 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
766 if (item_size >= sizeof(*ei)) {
767 ei = btrfs_item_ptr(leaf, path->slots[0],
768 struct btrfs_extent_item);
769 num_refs = btrfs_extent_refs(leaf, ei);
770 extent_flags = btrfs_extent_flags(leaf, ei);
772 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
773 struct btrfs_extent_item_v0 *ei0;
774 BUG_ON(item_size != sizeof(*ei0));
775 ei0 = btrfs_item_ptr(leaf, path->slots[0],
776 struct btrfs_extent_item_v0);
777 num_refs = btrfs_extent_refs_v0(leaf, ei0);
778 /* FIXME: this isn't correct for data */
779 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
784 BUG_ON(num_refs == 0);
794 delayed_refs = &trans->transaction->delayed_refs;
795 spin_lock(&delayed_refs->lock);
796 head = btrfs_find_delayed_ref_head(trans, bytenr);
798 if (!mutex_trylock(&head->mutex)) {
799 atomic_inc(&head->node.refs);
800 spin_unlock(&delayed_refs->lock);
802 btrfs_release_path(path);
805 * Mutex was contended, block until it's released and try
808 mutex_lock(&head->mutex);
809 mutex_unlock(&head->mutex);
810 btrfs_put_delayed_ref(&head->node);
813 if (head->extent_op && head->extent_op->update_flags)
814 extent_flags |= head->extent_op->flags_to_set;
816 BUG_ON(num_refs == 0);
818 num_refs += head->node.ref_mod;
819 mutex_unlock(&head->mutex);
821 spin_unlock(&delayed_refs->lock);
823 WARN_ON(num_refs == 0);
827 *flags = extent_flags;
829 btrfs_free_path(path);
834 * Back reference rules. Back refs have three main goals:
836 * 1) differentiate between all holders of references to an extent so that
837 * when a reference is dropped we can make sure it was a valid reference
838 * before freeing the extent.
840 * 2) Provide enough information to quickly find the holders of an extent
841 * if we notice a given block is corrupted or bad.
843 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
844 * maintenance. This is actually the same as #2, but with a slightly
845 * different use case.
847 * There are two kinds of back refs. The implicit back refs is optimized
848 * for pointers in non-shared tree blocks. For a given pointer in a block,
849 * back refs of this kind provide information about the block's owner tree
850 * and the pointer's key. These information allow us to find the block by
851 * b-tree searching. The full back refs is for pointers in tree blocks not
852 * referenced by their owner trees. The location of tree block is recorded
853 * in the back refs. Actually the full back refs is generic, and can be
854 * used in all cases the implicit back refs is used. The major shortcoming
855 * of the full back refs is its overhead. Every time a tree block gets
856 * COWed, we have to update back refs entry for all pointers in it.
858 * For a newly allocated tree block, we use implicit back refs for
859 * pointers in it. This means most tree related operations only involve
860 * implicit back refs. For a tree block created in old transaction, the
861 * only way to drop a reference to it is COW it. So we can detect the
862 * event that tree block loses its owner tree's reference and do the
863 * back refs conversion.
865 * When a tree block is COW'd through a tree, there are four cases:
867 * The reference count of the block is one and the tree is the block's
868 * owner tree. Nothing to do in this case.
870 * The reference count of the block is one and the tree is not the
871 * block's owner tree. In this case, full back refs is used for pointers
872 * in the block. Remove these full back refs, add implicit back refs for
873 * every pointers in the new block.
875 * The reference count of the block is greater than one and the tree is
876 * the block's owner tree. In this case, implicit back refs is used for
877 * pointers in the block. Add full back refs for every pointers in the
878 * block, increase lower level extents' reference counts. The original
879 * implicit back refs are entailed to the new block.
881 * The reference count of the block is greater than one and the tree is
882 * not the block's owner tree. Add implicit back refs for every pointer in
883 * the new block, increase lower level extents' reference count.
885 * Back Reference Key composing:
887 * The key objectid corresponds to the first byte in the extent,
888 * The key type is used to differentiate between types of back refs.
889 * There are different meanings of the key offset for different types
892 * File extents can be referenced by:
894 * - multiple snapshots, subvolumes, or different generations in one subvol
895 * - different files inside a single subvolume
896 * - different offsets inside a file (bookend extents in file.c)
898 * The extent ref structure for the implicit back refs has fields for:
900 * - Objectid of the subvolume root
901 * - objectid of the file holding the reference
902 * - original offset in the file
903 * - how many bookend extents
905 * The key offset for the implicit back refs is hash of the first
908 * The extent ref structure for the full back refs has field for:
910 * - number of pointers in the tree leaf
912 * The key offset for the implicit back refs is the first byte of
915 * When a file extent is allocated, The implicit back refs is used.
916 * the fields are filled in:
918 * (root_key.objectid, inode objectid, offset in file, 1)
920 * When a file extent is removed file truncation, we find the
921 * corresponding implicit back refs and check the following fields:
923 * (btrfs_header_owner(leaf), inode objectid, offset in file)
925 * Btree extents can be referenced by:
927 * - Different subvolumes
929 * Both the implicit back refs and the full back refs for tree blocks
930 * only consist of key. The key offset for the implicit back refs is
931 * objectid of block's owner tree. The key offset for the full back refs
932 * is the first byte of parent block.
934 * When implicit back refs is used, information about the lowest key and
935 * level of the tree block are required. These information are stored in
936 * tree block info structure.
939 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
940 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
941 struct btrfs_root *root,
942 struct btrfs_path *path,
943 u64 owner, u32 extra_size)
945 struct btrfs_extent_item *item;
946 struct btrfs_extent_item_v0 *ei0;
947 struct btrfs_extent_ref_v0 *ref0;
948 struct btrfs_tree_block_info *bi;
949 struct extent_buffer *leaf;
950 struct btrfs_key key;
951 struct btrfs_key found_key;
952 u32 new_size = sizeof(*item);
956 leaf = path->nodes[0];
957 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
959 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
960 ei0 = btrfs_item_ptr(leaf, path->slots[0],
961 struct btrfs_extent_item_v0);
962 refs = btrfs_extent_refs_v0(leaf, ei0);
964 if (owner == (u64)-1) {
966 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
967 ret = btrfs_next_leaf(root, path);
970 BUG_ON(ret > 0); /* Corruption */
971 leaf = path->nodes[0];
973 btrfs_item_key_to_cpu(leaf, &found_key,
975 BUG_ON(key.objectid != found_key.objectid);
976 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
980 ref0 = btrfs_item_ptr(leaf, path->slots[0],
981 struct btrfs_extent_ref_v0);
982 owner = btrfs_ref_objectid_v0(leaf, ref0);
986 btrfs_release_path(path);
988 if (owner < BTRFS_FIRST_FREE_OBJECTID)
989 new_size += sizeof(*bi);
991 new_size -= sizeof(*ei0);
992 ret = btrfs_search_slot(trans, root, &key, path,
993 new_size + extra_size, 1);
996 BUG_ON(ret); /* Corruption */
998 btrfs_extend_item(trans, root, path, new_size);
1000 leaf = path->nodes[0];
1001 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1002 btrfs_set_extent_refs(leaf, item, refs);
1003 /* FIXME: get real generation */
1004 btrfs_set_extent_generation(leaf, item, 0);
1005 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1006 btrfs_set_extent_flags(leaf, item,
1007 BTRFS_EXTENT_FLAG_TREE_BLOCK |
1008 BTRFS_BLOCK_FLAG_FULL_BACKREF);
1009 bi = (struct btrfs_tree_block_info *)(item + 1);
1010 /* FIXME: get first key of the block */
1011 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
1012 btrfs_set_tree_block_level(leaf, bi, (int)owner);
1014 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
1016 btrfs_mark_buffer_dirty(leaf);
1021 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
1023 u32 high_crc = ~(u32)0;
1024 u32 low_crc = ~(u32)0;
1027 lenum = cpu_to_le64(root_objectid);
1028 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
1029 lenum = cpu_to_le64(owner);
1030 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1031 lenum = cpu_to_le64(offset);
1032 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1034 return ((u64)high_crc << 31) ^ (u64)low_crc;
1037 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1038 struct btrfs_extent_data_ref *ref)
1040 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1041 btrfs_extent_data_ref_objectid(leaf, ref),
1042 btrfs_extent_data_ref_offset(leaf, ref));
1045 static int match_extent_data_ref(struct extent_buffer *leaf,
1046 struct btrfs_extent_data_ref *ref,
1047 u64 root_objectid, u64 owner, u64 offset)
1049 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1050 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1051 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1056 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1057 struct btrfs_root *root,
1058 struct btrfs_path *path,
1059 u64 bytenr, u64 parent,
1061 u64 owner, u64 offset)
1063 struct btrfs_key key;
1064 struct btrfs_extent_data_ref *ref;
1065 struct extent_buffer *leaf;
1071 key.objectid = bytenr;
1073 key.type = BTRFS_SHARED_DATA_REF_KEY;
1074 key.offset = parent;
1076 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1077 key.offset = hash_extent_data_ref(root_objectid,
1082 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1091 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1092 key.type = BTRFS_EXTENT_REF_V0_KEY;
1093 btrfs_release_path(path);
1094 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1105 leaf = path->nodes[0];
1106 nritems = btrfs_header_nritems(leaf);
1108 if (path->slots[0] >= nritems) {
1109 ret = btrfs_next_leaf(root, path);
1115 leaf = path->nodes[0];
1116 nritems = btrfs_header_nritems(leaf);
1120 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1121 if (key.objectid != bytenr ||
1122 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1125 ref = btrfs_item_ptr(leaf, path->slots[0],
1126 struct btrfs_extent_data_ref);
1128 if (match_extent_data_ref(leaf, ref, root_objectid,
1131 btrfs_release_path(path);
1143 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1144 struct btrfs_root *root,
1145 struct btrfs_path *path,
1146 u64 bytenr, u64 parent,
1147 u64 root_objectid, u64 owner,
1148 u64 offset, int refs_to_add)
1150 struct btrfs_key key;
1151 struct extent_buffer *leaf;
1156 key.objectid = bytenr;
1158 key.type = BTRFS_SHARED_DATA_REF_KEY;
1159 key.offset = parent;
1160 size = sizeof(struct btrfs_shared_data_ref);
1162 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1163 key.offset = hash_extent_data_ref(root_objectid,
1165 size = sizeof(struct btrfs_extent_data_ref);
1168 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1169 if (ret && ret != -EEXIST)
1172 leaf = path->nodes[0];
1174 struct btrfs_shared_data_ref *ref;
1175 ref = btrfs_item_ptr(leaf, path->slots[0],
1176 struct btrfs_shared_data_ref);
1178 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1180 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1181 num_refs += refs_to_add;
1182 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1185 struct btrfs_extent_data_ref *ref;
1186 while (ret == -EEXIST) {
1187 ref = btrfs_item_ptr(leaf, path->slots[0],
1188 struct btrfs_extent_data_ref);
1189 if (match_extent_data_ref(leaf, ref, root_objectid,
1192 btrfs_release_path(path);
1194 ret = btrfs_insert_empty_item(trans, root, path, &key,
1196 if (ret && ret != -EEXIST)
1199 leaf = path->nodes[0];
1201 ref = btrfs_item_ptr(leaf, path->slots[0],
1202 struct btrfs_extent_data_ref);
1204 btrfs_set_extent_data_ref_root(leaf, ref,
1206 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1207 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1208 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1210 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1211 num_refs += refs_to_add;
1212 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1215 btrfs_mark_buffer_dirty(leaf);
1218 btrfs_release_path(path);
1222 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1223 struct btrfs_root *root,
1224 struct btrfs_path *path,
1227 struct btrfs_key key;
1228 struct btrfs_extent_data_ref *ref1 = NULL;
1229 struct btrfs_shared_data_ref *ref2 = NULL;
1230 struct extent_buffer *leaf;
1234 leaf = path->nodes[0];
1235 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1237 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1238 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1239 struct btrfs_extent_data_ref);
1240 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1241 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1242 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1243 struct btrfs_shared_data_ref);
1244 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1245 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1246 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1247 struct btrfs_extent_ref_v0 *ref0;
1248 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1249 struct btrfs_extent_ref_v0);
1250 num_refs = btrfs_ref_count_v0(leaf, ref0);
1256 BUG_ON(num_refs < refs_to_drop);
1257 num_refs -= refs_to_drop;
1259 if (num_refs == 0) {
1260 ret = btrfs_del_item(trans, root, path);
1262 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1263 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1264 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1265 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1266 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1268 struct btrfs_extent_ref_v0 *ref0;
1269 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1270 struct btrfs_extent_ref_v0);
1271 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1274 btrfs_mark_buffer_dirty(leaf);
1279 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1280 struct btrfs_path *path,
1281 struct btrfs_extent_inline_ref *iref)
1283 struct btrfs_key key;
1284 struct extent_buffer *leaf;
1285 struct btrfs_extent_data_ref *ref1;
1286 struct btrfs_shared_data_ref *ref2;
1289 leaf = path->nodes[0];
1290 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1292 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1293 BTRFS_EXTENT_DATA_REF_KEY) {
1294 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1295 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1297 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1298 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1300 } else 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 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1309 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1310 struct btrfs_extent_ref_v0 *ref0;
1311 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1312 struct btrfs_extent_ref_v0);
1313 num_refs = btrfs_ref_count_v0(leaf, ref0);
1321 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1322 struct btrfs_root *root,
1323 struct btrfs_path *path,
1324 u64 bytenr, u64 parent,
1327 struct btrfs_key key;
1330 key.objectid = bytenr;
1332 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1333 key.offset = parent;
1335 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1336 key.offset = root_objectid;
1339 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1342 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1343 if (ret == -ENOENT && parent) {
1344 btrfs_release_path(path);
1345 key.type = BTRFS_EXTENT_REF_V0_KEY;
1346 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1354 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1355 struct btrfs_root *root,
1356 struct btrfs_path *path,
1357 u64 bytenr, u64 parent,
1360 struct btrfs_key key;
1363 key.objectid = bytenr;
1365 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1366 key.offset = parent;
1368 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1369 key.offset = root_objectid;
1372 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1373 btrfs_release_path(path);
1377 static inline int extent_ref_type(u64 parent, u64 owner)
1380 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1382 type = BTRFS_SHARED_BLOCK_REF_KEY;
1384 type = BTRFS_TREE_BLOCK_REF_KEY;
1387 type = BTRFS_SHARED_DATA_REF_KEY;
1389 type = BTRFS_EXTENT_DATA_REF_KEY;
1394 static int find_next_key(struct btrfs_path *path, int level,
1395 struct btrfs_key *key)
1398 for (; level < BTRFS_MAX_LEVEL; level++) {
1399 if (!path->nodes[level])
1401 if (path->slots[level] + 1 >=
1402 btrfs_header_nritems(path->nodes[level]))
1405 btrfs_item_key_to_cpu(path->nodes[level], key,
1406 path->slots[level] + 1);
1408 btrfs_node_key_to_cpu(path->nodes[level], key,
1409 path->slots[level] + 1);
1416 * look for inline back ref. if back ref is found, *ref_ret is set
1417 * to the address of inline back ref, and 0 is returned.
1419 * if back ref isn't found, *ref_ret is set to the address where it
1420 * should be inserted, and -ENOENT is returned.
1422 * if insert is true and there are too many inline back refs, the path
1423 * points to the extent item, and -EAGAIN is returned.
1425 * NOTE: inline back refs are ordered in the same way that back ref
1426 * items in the tree are ordered.
1428 static noinline_for_stack
1429 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1430 struct btrfs_root *root,
1431 struct btrfs_path *path,
1432 struct btrfs_extent_inline_ref **ref_ret,
1433 u64 bytenr, u64 num_bytes,
1434 u64 parent, u64 root_objectid,
1435 u64 owner, u64 offset, int insert)
1437 struct btrfs_key key;
1438 struct extent_buffer *leaf;
1439 struct btrfs_extent_item *ei;
1440 struct btrfs_extent_inline_ref *iref;
1451 key.objectid = bytenr;
1452 key.type = BTRFS_EXTENT_ITEM_KEY;
1453 key.offset = num_bytes;
1455 want = extent_ref_type(parent, owner);
1457 extra_size = btrfs_extent_inline_ref_size(want);
1458 path->keep_locks = 1;
1461 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1466 if (ret && !insert) {
1470 BUG_ON(ret); /* Corruption */
1472 leaf = path->nodes[0];
1473 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1474 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1475 if (item_size < sizeof(*ei)) {
1480 ret = convert_extent_item_v0(trans, root, path, owner,
1486 leaf = path->nodes[0];
1487 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1490 BUG_ON(item_size < sizeof(*ei));
1492 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1493 flags = btrfs_extent_flags(leaf, ei);
1495 ptr = (unsigned long)(ei + 1);
1496 end = (unsigned long)ei + item_size;
1498 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1499 ptr += sizeof(struct btrfs_tree_block_info);
1502 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1511 iref = (struct btrfs_extent_inline_ref *)ptr;
1512 type = btrfs_extent_inline_ref_type(leaf, iref);
1516 ptr += btrfs_extent_inline_ref_size(type);
1520 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1521 struct btrfs_extent_data_ref *dref;
1522 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1523 if (match_extent_data_ref(leaf, dref, root_objectid,
1528 if (hash_extent_data_ref_item(leaf, dref) <
1529 hash_extent_data_ref(root_objectid, owner, offset))
1533 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1535 if (parent == ref_offset) {
1539 if (ref_offset < parent)
1542 if (root_objectid == ref_offset) {
1546 if (ref_offset < root_objectid)
1550 ptr += btrfs_extent_inline_ref_size(type);
1552 if (err == -ENOENT && insert) {
1553 if (item_size + extra_size >=
1554 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1559 * To add new inline back ref, we have to make sure
1560 * there is no corresponding back ref item.
1561 * For simplicity, we just do not add new inline back
1562 * ref if there is any kind of item for this block
1564 if (find_next_key(path, 0, &key) == 0 &&
1565 key.objectid == bytenr &&
1566 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1571 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1574 path->keep_locks = 0;
1575 btrfs_unlock_up_safe(path, 1);
1581 * helper to add new inline back ref
1583 static noinline_for_stack
1584 void setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1585 struct btrfs_root *root,
1586 struct btrfs_path *path,
1587 struct btrfs_extent_inline_ref *iref,
1588 u64 parent, u64 root_objectid,
1589 u64 owner, u64 offset, int refs_to_add,
1590 struct btrfs_delayed_extent_op *extent_op)
1592 struct extent_buffer *leaf;
1593 struct btrfs_extent_item *ei;
1596 unsigned long item_offset;
1601 leaf = path->nodes[0];
1602 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1603 item_offset = (unsigned long)iref - (unsigned long)ei;
1605 type = extent_ref_type(parent, owner);
1606 size = btrfs_extent_inline_ref_size(type);
1608 btrfs_extend_item(trans, root, path, size);
1610 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1611 refs = btrfs_extent_refs(leaf, ei);
1612 refs += refs_to_add;
1613 btrfs_set_extent_refs(leaf, ei, refs);
1615 __run_delayed_extent_op(extent_op, leaf, ei);
1617 ptr = (unsigned long)ei + item_offset;
1618 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1619 if (ptr < end - size)
1620 memmove_extent_buffer(leaf, ptr + size, ptr,
1623 iref = (struct btrfs_extent_inline_ref *)ptr;
1624 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1625 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1626 struct btrfs_extent_data_ref *dref;
1627 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1628 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1629 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1630 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1631 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1632 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1633 struct btrfs_shared_data_ref *sref;
1634 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1635 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1636 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1637 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1638 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1640 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1642 btrfs_mark_buffer_dirty(leaf);
1645 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1646 struct btrfs_root *root,
1647 struct btrfs_path *path,
1648 struct btrfs_extent_inline_ref **ref_ret,
1649 u64 bytenr, u64 num_bytes, u64 parent,
1650 u64 root_objectid, u64 owner, u64 offset)
1654 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1655 bytenr, num_bytes, parent,
1656 root_objectid, owner, offset, 0);
1660 btrfs_release_path(path);
1663 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1664 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1667 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1668 root_objectid, owner, offset);
1674 * helper to update/remove inline back ref
1676 static noinline_for_stack
1677 void update_inline_extent_backref(struct btrfs_trans_handle *trans,
1678 struct btrfs_root *root,
1679 struct btrfs_path *path,
1680 struct btrfs_extent_inline_ref *iref,
1682 struct btrfs_delayed_extent_op *extent_op)
1684 struct extent_buffer *leaf;
1685 struct btrfs_extent_item *ei;
1686 struct btrfs_extent_data_ref *dref = NULL;
1687 struct btrfs_shared_data_ref *sref = NULL;
1695 leaf = path->nodes[0];
1696 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1697 refs = btrfs_extent_refs(leaf, ei);
1698 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1699 refs += refs_to_mod;
1700 btrfs_set_extent_refs(leaf, ei, refs);
1702 __run_delayed_extent_op(extent_op, leaf, ei);
1704 type = btrfs_extent_inline_ref_type(leaf, iref);
1706 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1707 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1708 refs = btrfs_extent_data_ref_count(leaf, dref);
1709 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1710 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1711 refs = btrfs_shared_data_ref_count(leaf, sref);
1714 BUG_ON(refs_to_mod != -1);
1717 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1718 refs += refs_to_mod;
1721 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1722 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1724 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1726 size = btrfs_extent_inline_ref_size(type);
1727 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1728 ptr = (unsigned long)iref;
1729 end = (unsigned long)ei + item_size;
1730 if (ptr + size < end)
1731 memmove_extent_buffer(leaf, ptr, ptr + size,
1734 btrfs_truncate_item(trans, root, path, item_size, 1);
1736 btrfs_mark_buffer_dirty(leaf);
1739 static noinline_for_stack
1740 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1741 struct btrfs_root *root,
1742 struct btrfs_path *path,
1743 u64 bytenr, u64 num_bytes, u64 parent,
1744 u64 root_objectid, u64 owner,
1745 u64 offset, int refs_to_add,
1746 struct btrfs_delayed_extent_op *extent_op)
1748 struct btrfs_extent_inline_ref *iref;
1751 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1752 bytenr, num_bytes, parent,
1753 root_objectid, owner, offset, 1);
1755 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1756 update_inline_extent_backref(trans, root, path, iref,
1757 refs_to_add, extent_op);
1758 } else if (ret == -ENOENT) {
1759 setup_inline_extent_backref(trans, root, path, iref, parent,
1760 root_objectid, owner, offset,
1761 refs_to_add, extent_op);
1767 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1768 struct btrfs_root *root,
1769 struct btrfs_path *path,
1770 u64 bytenr, u64 parent, u64 root_objectid,
1771 u64 owner, u64 offset, int refs_to_add)
1774 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1775 BUG_ON(refs_to_add != 1);
1776 ret = insert_tree_block_ref(trans, root, path, bytenr,
1777 parent, root_objectid);
1779 ret = insert_extent_data_ref(trans, root, path, bytenr,
1780 parent, root_objectid,
1781 owner, offset, refs_to_add);
1786 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1787 struct btrfs_root *root,
1788 struct btrfs_path *path,
1789 struct btrfs_extent_inline_ref *iref,
1790 int refs_to_drop, int is_data)
1794 BUG_ON(!is_data && refs_to_drop != 1);
1796 update_inline_extent_backref(trans, root, path, iref,
1797 -refs_to_drop, NULL);
1798 } else if (is_data) {
1799 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1801 ret = btrfs_del_item(trans, root, path);
1806 static int btrfs_issue_discard(struct block_device *bdev,
1809 return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0);
1812 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1813 u64 num_bytes, u64 *actual_bytes)
1816 u64 discarded_bytes = 0;
1817 struct btrfs_bio *bbio = NULL;
1820 /* Tell the block device(s) that the sectors can be discarded */
1821 ret = btrfs_map_block(root->fs_info, REQ_DISCARD,
1822 bytenr, &num_bytes, &bbio, 0);
1823 /* Error condition is -ENOMEM */
1825 struct btrfs_bio_stripe *stripe = bbio->stripes;
1829 for (i = 0; i < bbio->num_stripes; i++, stripe++) {
1830 if (!stripe->dev->can_discard)
1833 ret = btrfs_issue_discard(stripe->dev->bdev,
1837 discarded_bytes += stripe->length;
1838 else if (ret != -EOPNOTSUPP)
1839 break; /* Logic errors or -ENOMEM, or -EIO but I don't know how that could happen JDM */
1842 * Just in case we get back EOPNOTSUPP for some reason,
1843 * just ignore the return value so we don't screw up
1844 * people calling discard_extent.
1852 *actual_bytes = discarded_bytes;
1858 /* Can return -ENOMEM */
1859 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1860 struct btrfs_root *root,
1861 u64 bytenr, u64 num_bytes, u64 parent,
1862 u64 root_objectid, u64 owner, u64 offset, int for_cow)
1865 struct btrfs_fs_info *fs_info = root->fs_info;
1867 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1868 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1870 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1871 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
1873 parent, root_objectid, (int)owner,
1874 BTRFS_ADD_DELAYED_REF, NULL, for_cow);
1876 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
1878 parent, root_objectid, owner, offset,
1879 BTRFS_ADD_DELAYED_REF, NULL, for_cow);
1884 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1885 struct btrfs_root *root,
1886 u64 bytenr, u64 num_bytes,
1887 u64 parent, u64 root_objectid,
1888 u64 owner, u64 offset, int refs_to_add,
1889 struct btrfs_delayed_extent_op *extent_op)
1891 struct btrfs_path *path;
1892 struct extent_buffer *leaf;
1893 struct btrfs_extent_item *item;
1898 path = btrfs_alloc_path();
1903 path->leave_spinning = 1;
1904 /* this will setup the path even if it fails to insert the back ref */
1905 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1906 path, bytenr, num_bytes, parent,
1907 root_objectid, owner, offset,
1908 refs_to_add, extent_op);
1912 if (ret != -EAGAIN) {
1917 leaf = path->nodes[0];
1918 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1919 refs = btrfs_extent_refs(leaf, item);
1920 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1922 __run_delayed_extent_op(extent_op, leaf, item);
1924 btrfs_mark_buffer_dirty(leaf);
1925 btrfs_release_path(path);
1928 path->leave_spinning = 1;
1930 /* now insert the actual backref */
1931 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1932 path, bytenr, parent, root_objectid,
1933 owner, offset, refs_to_add);
1935 btrfs_abort_transaction(trans, root, ret);
1937 btrfs_free_path(path);
1941 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1942 struct btrfs_root *root,
1943 struct btrfs_delayed_ref_node *node,
1944 struct btrfs_delayed_extent_op *extent_op,
1945 int insert_reserved)
1948 struct btrfs_delayed_data_ref *ref;
1949 struct btrfs_key ins;
1954 ins.objectid = node->bytenr;
1955 ins.offset = node->num_bytes;
1956 ins.type = BTRFS_EXTENT_ITEM_KEY;
1958 ref = btrfs_delayed_node_to_data_ref(node);
1959 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1960 parent = ref->parent;
1962 ref_root = ref->root;
1964 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1966 BUG_ON(extent_op->update_key);
1967 flags |= extent_op->flags_to_set;
1969 ret = alloc_reserved_file_extent(trans, root,
1970 parent, ref_root, flags,
1971 ref->objectid, ref->offset,
1972 &ins, node->ref_mod);
1973 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1974 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1975 node->num_bytes, parent,
1976 ref_root, ref->objectid,
1977 ref->offset, node->ref_mod,
1979 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1980 ret = __btrfs_free_extent(trans, root, node->bytenr,
1981 node->num_bytes, parent,
1982 ref_root, ref->objectid,
1983 ref->offset, node->ref_mod,
1991 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1992 struct extent_buffer *leaf,
1993 struct btrfs_extent_item *ei)
1995 u64 flags = btrfs_extent_flags(leaf, ei);
1996 if (extent_op->update_flags) {
1997 flags |= extent_op->flags_to_set;
1998 btrfs_set_extent_flags(leaf, ei, flags);
2001 if (extent_op->update_key) {
2002 struct btrfs_tree_block_info *bi;
2003 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
2004 bi = (struct btrfs_tree_block_info *)(ei + 1);
2005 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
2009 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
2010 struct btrfs_root *root,
2011 struct btrfs_delayed_ref_node *node,
2012 struct btrfs_delayed_extent_op *extent_op)
2014 struct btrfs_key key;
2015 struct btrfs_path *path;
2016 struct btrfs_extent_item *ei;
2017 struct extent_buffer *leaf;
2025 path = btrfs_alloc_path();
2029 key.objectid = node->bytenr;
2030 key.type = BTRFS_EXTENT_ITEM_KEY;
2031 key.offset = node->num_bytes;
2034 path->leave_spinning = 1;
2035 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
2046 leaf = path->nodes[0];
2047 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2048 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2049 if (item_size < sizeof(*ei)) {
2050 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
2056 leaf = path->nodes[0];
2057 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2060 BUG_ON(item_size < sizeof(*ei));
2061 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2062 __run_delayed_extent_op(extent_op, leaf, ei);
2064 btrfs_mark_buffer_dirty(leaf);
2066 btrfs_free_path(path);
2070 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2071 struct btrfs_root *root,
2072 struct btrfs_delayed_ref_node *node,
2073 struct btrfs_delayed_extent_op *extent_op,
2074 int insert_reserved)
2077 struct btrfs_delayed_tree_ref *ref;
2078 struct btrfs_key ins;
2082 ins.objectid = node->bytenr;
2083 ins.offset = node->num_bytes;
2084 ins.type = BTRFS_EXTENT_ITEM_KEY;
2086 ref = btrfs_delayed_node_to_tree_ref(node);
2087 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2088 parent = ref->parent;
2090 ref_root = ref->root;
2092 BUG_ON(node->ref_mod != 1);
2093 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2094 BUG_ON(!extent_op || !extent_op->update_flags ||
2095 !extent_op->update_key);
2096 ret = alloc_reserved_tree_block(trans, root,
2098 extent_op->flags_to_set,
2101 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2102 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2103 node->num_bytes, parent, ref_root,
2104 ref->level, 0, 1, extent_op);
2105 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2106 ret = __btrfs_free_extent(trans, root, node->bytenr,
2107 node->num_bytes, parent, ref_root,
2108 ref->level, 0, 1, extent_op);
2115 /* helper function to actually process a single delayed ref entry */
2116 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2117 struct btrfs_root *root,
2118 struct btrfs_delayed_ref_node *node,
2119 struct btrfs_delayed_extent_op *extent_op,
2120 int insert_reserved)
2127 if (btrfs_delayed_ref_is_head(node)) {
2128 struct btrfs_delayed_ref_head *head;
2130 * we've hit the end of the chain and we were supposed
2131 * to insert this extent into the tree. But, it got
2132 * deleted before we ever needed to insert it, so all
2133 * we have to do is clean up the accounting
2136 head = btrfs_delayed_node_to_head(node);
2137 if (insert_reserved) {
2138 btrfs_pin_extent(root, node->bytenr,
2139 node->num_bytes, 1);
2140 if (head->is_data) {
2141 ret = btrfs_del_csums(trans, root,
2149 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2150 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2151 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2153 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2154 node->type == BTRFS_SHARED_DATA_REF_KEY)
2155 ret = run_delayed_data_ref(trans, root, node, extent_op,
2162 static noinline struct btrfs_delayed_ref_node *
2163 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2165 struct rb_node *node;
2166 struct btrfs_delayed_ref_node *ref;
2167 int action = BTRFS_ADD_DELAYED_REF;
2170 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2171 * this prevents ref count from going down to zero when
2172 * there still are pending delayed ref.
2174 node = rb_prev(&head->node.rb_node);
2178 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2180 if (ref->bytenr != head->node.bytenr)
2182 if (ref->action == action)
2184 node = rb_prev(node);
2186 if (action == BTRFS_ADD_DELAYED_REF) {
2187 action = BTRFS_DROP_DELAYED_REF;
2194 * Returns 0 on success or if called with an already aborted transaction.
2195 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
2197 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2198 struct btrfs_root *root,
2199 struct list_head *cluster)
2201 struct btrfs_delayed_ref_root *delayed_refs;
2202 struct btrfs_delayed_ref_node *ref;
2203 struct btrfs_delayed_ref_head *locked_ref = NULL;
2204 struct btrfs_delayed_extent_op *extent_op;
2205 struct btrfs_fs_info *fs_info = root->fs_info;
2208 int must_insert_reserved = 0;
2210 delayed_refs = &trans->transaction->delayed_refs;
2213 /* pick a new head ref from the cluster list */
2214 if (list_empty(cluster))
2217 locked_ref = list_entry(cluster->next,
2218 struct btrfs_delayed_ref_head, cluster);
2220 /* grab the lock that says we are going to process
2221 * all the refs for this head */
2222 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2225 * we may have dropped the spin lock to get the head
2226 * mutex lock, and that might have given someone else
2227 * time to free the head. If that's true, it has been
2228 * removed from our list and we can move on.
2230 if (ret == -EAGAIN) {
2238 * We need to try and merge add/drops of the same ref since we
2239 * can run into issues with relocate dropping the implicit ref
2240 * and then it being added back again before the drop can
2241 * finish. If we merged anything we need to re-loop so we can
2244 btrfs_merge_delayed_refs(trans, fs_info, delayed_refs,
2248 * locked_ref is the head node, so we have to go one
2249 * node back for any delayed ref updates
2251 ref = select_delayed_ref(locked_ref);
2253 if (ref && ref->seq &&
2254 btrfs_check_delayed_seq(fs_info, delayed_refs, ref->seq)) {
2256 * there are still refs with lower seq numbers in the
2257 * process of being added. Don't run this ref yet.
2259 list_del_init(&locked_ref->cluster);
2260 btrfs_delayed_ref_unlock(locked_ref);
2262 delayed_refs->num_heads_ready++;
2263 spin_unlock(&delayed_refs->lock);
2265 spin_lock(&delayed_refs->lock);
2270 * record the must insert reserved flag before we
2271 * drop the spin lock.
2273 must_insert_reserved = locked_ref->must_insert_reserved;
2274 locked_ref->must_insert_reserved = 0;
2276 extent_op = locked_ref->extent_op;
2277 locked_ref->extent_op = NULL;
2280 /* All delayed refs have been processed, Go ahead
2281 * and send the head node to run_one_delayed_ref,
2282 * so that any accounting fixes can happen
2284 ref = &locked_ref->node;
2286 if (extent_op && must_insert_reserved) {
2287 btrfs_free_delayed_extent_op(extent_op);
2292 spin_unlock(&delayed_refs->lock);
2294 ret = run_delayed_extent_op(trans, root,
2296 btrfs_free_delayed_extent_op(extent_op);
2300 "btrfs: run_delayed_extent_op "
2301 "returned %d\n", ret);
2302 spin_lock(&delayed_refs->lock);
2303 btrfs_delayed_ref_unlock(locked_ref);
2312 rb_erase(&ref->rb_node, &delayed_refs->root);
2313 delayed_refs->num_entries--;
2314 if (!btrfs_delayed_ref_is_head(ref)) {
2316 * when we play the delayed ref, also correct the
2319 switch (ref->action) {
2320 case BTRFS_ADD_DELAYED_REF:
2321 case BTRFS_ADD_DELAYED_EXTENT:
2322 locked_ref->node.ref_mod -= ref->ref_mod;
2324 case BTRFS_DROP_DELAYED_REF:
2325 locked_ref->node.ref_mod += ref->ref_mod;
2331 spin_unlock(&delayed_refs->lock);
2333 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2334 must_insert_reserved);
2336 btrfs_free_delayed_extent_op(extent_op);
2338 btrfs_delayed_ref_unlock(locked_ref);
2339 btrfs_put_delayed_ref(ref);
2341 "btrfs: run_one_delayed_ref returned %d\n", ret);
2342 spin_lock(&delayed_refs->lock);
2347 * If this node is a head, that means all the refs in this head
2348 * have been dealt with, and we will pick the next head to deal
2349 * with, so we must unlock the head and drop it from the cluster
2350 * list before we release it.
2352 if (btrfs_delayed_ref_is_head(ref)) {
2353 list_del_init(&locked_ref->cluster);
2354 btrfs_delayed_ref_unlock(locked_ref);
2357 btrfs_put_delayed_ref(ref);
2361 spin_lock(&delayed_refs->lock);
2366 #ifdef SCRAMBLE_DELAYED_REFS
2368 * Normally delayed refs get processed in ascending bytenr order. This
2369 * correlates in most cases to the order added. To expose dependencies on this
2370 * order, we start to process the tree in the middle instead of the beginning
2372 static u64 find_middle(struct rb_root *root)
2374 struct rb_node *n = root->rb_node;
2375 struct btrfs_delayed_ref_node *entry;
2378 u64 first = 0, last = 0;
2382 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2383 first = entry->bytenr;
2387 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2388 last = entry->bytenr;
2393 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2394 WARN_ON(!entry->in_tree);
2396 middle = entry->bytenr;
2409 int btrfs_delayed_refs_qgroup_accounting(struct btrfs_trans_handle *trans,
2410 struct btrfs_fs_info *fs_info)
2412 struct qgroup_update *qgroup_update;
2415 if (list_empty(&trans->qgroup_ref_list) !=
2416 !trans->delayed_ref_elem.seq) {
2417 /* list without seq or seq without list */
2418 printk(KERN_ERR "btrfs: qgroup accounting update error, list is%s empty, seq is %llu\n",
2419 list_empty(&trans->qgroup_ref_list) ? "" : " not",
2420 trans->delayed_ref_elem.seq);
2424 if (!trans->delayed_ref_elem.seq)
2427 while (!list_empty(&trans->qgroup_ref_list)) {
2428 qgroup_update = list_first_entry(&trans->qgroup_ref_list,
2429 struct qgroup_update, list);
2430 list_del(&qgroup_update->list);
2432 ret = btrfs_qgroup_account_ref(
2433 trans, fs_info, qgroup_update->node,
2434 qgroup_update->extent_op);
2435 kfree(qgroup_update);
2438 btrfs_put_tree_mod_seq(fs_info, &trans->delayed_ref_elem);
2444 * this starts processing the delayed reference count updates and
2445 * extent insertions we have queued up so far. count can be
2446 * 0, which means to process everything in the tree at the start
2447 * of the run (but not newly added entries), or it can be some target
2448 * number you'd like to process.
2450 * Returns 0 on success or if called with an aborted transaction
2451 * Returns <0 on error and aborts the transaction
2453 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2454 struct btrfs_root *root, unsigned long count)
2456 struct rb_node *node;
2457 struct btrfs_delayed_ref_root *delayed_refs;
2458 struct btrfs_delayed_ref_node *ref;
2459 struct list_head cluster;
2462 int run_all = count == (unsigned long)-1;
2466 /* We'll clean this up in btrfs_cleanup_transaction */
2470 if (root == root->fs_info->extent_root)
2471 root = root->fs_info->tree_root;
2473 btrfs_delayed_refs_qgroup_accounting(trans, root->fs_info);
2475 delayed_refs = &trans->transaction->delayed_refs;
2476 INIT_LIST_HEAD(&cluster);
2479 spin_lock(&delayed_refs->lock);
2481 #ifdef SCRAMBLE_DELAYED_REFS
2482 delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
2486 count = delayed_refs->num_entries * 2;
2490 if (!(run_all || run_most) &&
2491 delayed_refs->num_heads_ready < 64)
2495 * go find something we can process in the rbtree. We start at
2496 * the beginning of the tree, and then build a cluster
2497 * of refs to process starting at the first one we are able to
2500 delayed_start = delayed_refs->run_delayed_start;
2501 ret = btrfs_find_ref_cluster(trans, &cluster,
2502 delayed_refs->run_delayed_start);
2506 ret = run_clustered_refs(trans, root, &cluster);
2508 btrfs_release_ref_cluster(&cluster);
2509 spin_unlock(&delayed_refs->lock);
2510 btrfs_abort_transaction(trans, root, ret);
2514 count -= min_t(unsigned long, ret, count);
2519 if (delayed_start >= delayed_refs->run_delayed_start) {
2522 * btrfs_find_ref_cluster looped. let's do one
2523 * more cycle. if we don't run any delayed ref
2524 * during that cycle (because we can't because
2525 * all of them are blocked), bail out.
2530 * no runnable refs left, stop trying
2537 /* refs were run, let's reset staleness detection */
2543 if (!list_empty(&trans->new_bgs)) {
2544 spin_unlock(&delayed_refs->lock);
2545 btrfs_create_pending_block_groups(trans, root);
2546 spin_lock(&delayed_refs->lock);
2549 node = rb_first(&delayed_refs->root);
2552 count = (unsigned long)-1;
2555 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2557 if (btrfs_delayed_ref_is_head(ref)) {
2558 struct btrfs_delayed_ref_head *head;
2560 head = btrfs_delayed_node_to_head(ref);
2561 atomic_inc(&ref->refs);
2563 spin_unlock(&delayed_refs->lock);
2565 * Mutex was contended, block until it's
2566 * released and try again
2568 mutex_lock(&head->mutex);
2569 mutex_unlock(&head->mutex);
2571 btrfs_put_delayed_ref(ref);
2575 node = rb_next(node);
2577 spin_unlock(&delayed_refs->lock);
2578 schedule_timeout(1);
2582 spin_unlock(&delayed_refs->lock);
2583 assert_qgroups_uptodate(trans);
2587 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2588 struct btrfs_root *root,
2589 u64 bytenr, u64 num_bytes, u64 flags,
2592 struct btrfs_delayed_extent_op *extent_op;
2595 extent_op = btrfs_alloc_delayed_extent_op();
2599 extent_op->flags_to_set = flags;
2600 extent_op->update_flags = 1;
2601 extent_op->update_key = 0;
2602 extent_op->is_data = is_data ? 1 : 0;
2604 ret = btrfs_add_delayed_extent_op(root->fs_info, trans, bytenr,
2605 num_bytes, extent_op);
2607 btrfs_free_delayed_extent_op(extent_op);
2611 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2612 struct btrfs_root *root,
2613 struct btrfs_path *path,
2614 u64 objectid, u64 offset, u64 bytenr)
2616 struct btrfs_delayed_ref_head *head;
2617 struct btrfs_delayed_ref_node *ref;
2618 struct btrfs_delayed_data_ref *data_ref;
2619 struct btrfs_delayed_ref_root *delayed_refs;
2620 struct rb_node *node;
2624 delayed_refs = &trans->transaction->delayed_refs;
2625 spin_lock(&delayed_refs->lock);
2626 head = btrfs_find_delayed_ref_head(trans, bytenr);
2630 if (!mutex_trylock(&head->mutex)) {
2631 atomic_inc(&head->node.refs);
2632 spin_unlock(&delayed_refs->lock);
2634 btrfs_release_path(path);
2637 * Mutex was contended, block until it's released and let
2640 mutex_lock(&head->mutex);
2641 mutex_unlock(&head->mutex);
2642 btrfs_put_delayed_ref(&head->node);
2646 node = rb_prev(&head->node.rb_node);
2650 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2652 if (ref->bytenr != bytenr)
2656 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2659 data_ref = btrfs_delayed_node_to_data_ref(ref);
2661 node = rb_prev(node);
2665 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2666 if (ref->bytenr == bytenr && ref->seq == seq)
2670 if (data_ref->root != root->root_key.objectid ||
2671 data_ref->objectid != objectid || data_ref->offset != offset)
2676 mutex_unlock(&head->mutex);
2678 spin_unlock(&delayed_refs->lock);
2682 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2683 struct btrfs_root *root,
2684 struct btrfs_path *path,
2685 u64 objectid, u64 offset, u64 bytenr)
2687 struct btrfs_root *extent_root = root->fs_info->extent_root;
2688 struct extent_buffer *leaf;
2689 struct btrfs_extent_data_ref *ref;
2690 struct btrfs_extent_inline_ref *iref;
2691 struct btrfs_extent_item *ei;
2692 struct btrfs_key key;
2696 key.objectid = bytenr;
2697 key.offset = (u64)-1;
2698 key.type = BTRFS_EXTENT_ITEM_KEY;
2700 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2703 BUG_ON(ret == 0); /* Corruption */
2706 if (path->slots[0] == 0)
2710 leaf = path->nodes[0];
2711 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2713 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2717 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2718 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2719 if (item_size < sizeof(*ei)) {
2720 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2724 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2726 if (item_size != sizeof(*ei) +
2727 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2730 if (btrfs_extent_generation(leaf, ei) <=
2731 btrfs_root_last_snapshot(&root->root_item))
2734 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2735 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2736 BTRFS_EXTENT_DATA_REF_KEY)
2739 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2740 if (btrfs_extent_refs(leaf, ei) !=
2741 btrfs_extent_data_ref_count(leaf, ref) ||
2742 btrfs_extent_data_ref_root(leaf, ref) !=
2743 root->root_key.objectid ||
2744 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2745 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2753 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2754 struct btrfs_root *root,
2755 u64 objectid, u64 offset, u64 bytenr)
2757 struct btrfs_path *path;
2761 path = btrfs_alloc_path();
2766 ret = check_committed_ref(trans, root, path, objectid,
2768 if (ret && ret != -ENOENT)
2771 ret2 = check_delayed_ref(trans, root, path, objectid,
2773 } while (ret2 == -EAGAIN);
2775 if (ret2 && ret2 != -ENOENT) {
2780 if (ret != -ENOENT || ret2 != -ENOENT)
2783 btrfs_free_path(path);
2784 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2789 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2790 struct btrfs_root *root,
2791 struct extent_buffer *buf,
2792 int full_backref, int inc, int for_cow)
2799 struct btrfs_key key;
2800 struct btrfs_file_extent_item *fi;
2804 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2805 u64, u64, u64, u64, u64, u64, int);
2807 ref_root = btrfs_header_owner(buf);
2808 nritems = btrfs_header_nritems(buf);
2809 level = btrfs_header_level(buf);
2811 if (!root->ref_cows && level == 0)
2815 process_func = btrfs_inc_extent_ref;
2817 process_func = btrfs_free_extent;
2820 parent = buf->start;
2824 for (i = 0; i < nritems; i++) {
2826 btrfs_item_key_to_cpu(buf, &key, i);
2827 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2829 fi = btrfs_item_ptr(buf, i,
2830 struct btrfs_file_extent_item);
2831 if (btrfs_file_extent_type(buf, fi) ==
2832 BTRFS_FILE_EXTENT_INLINE)
2834 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2838 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2839 key.offset -= btrfs_file_extent_offset(buf, fi);
2840 ret = process_func(trans, root, bytenr, num_bytes,
2841 parent, ref_root, key.objectid,
2842 key.offset, for_cow);
2846 bytenr = btrfs_node_blockptr(buf, i);
2847 num_bytes = btrfs_level_size(root, level - 1);
2848 ret = process_func(trans, root, bytenr, num_bytes,
2849 parent, ref_root, level - 1, 0,
2860 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2861 struct extent_buffer *buf, int full_backref, int for_cow)
2863 return __btrfs_mod_ref(trans, root, buf, full_backref, 1, for_cow);
2866 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2867 struct extent_buffer *buf, int full_backref, int for_cow)
2869 return __btrfs_mod_ref(trans, root, buf, full_backref, 0, for_cow);
2872 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2873 struct btrfs_root *root,
2874 struct btrfs_path *path,
2875 struct btrfs_block_group_cache *cache)
2878 struct btrfs_root *extent_root = root->fs_info->extent_root;
2880 struct extent_buffer *leaf;
2882 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2885 BUG_ON(ret); /* Corruption */
2887 leaf = path->nodes[0];
2888 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2889 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2890 btrfs_mark_buffer_dirty(leaf);
2891 btrfs_release_path(path);
2894 btrfs_abort_transaction(trans, root, ret);
2901 static struct btrfs_block_group_cache *
2902 next_block_group(struct btrfs_root *root,
2903 struct btrfs_block_group_cache *cache)
2905 struct rb_node *node;
2906 spin_lock(&root->fs_info->block_group_cache_lock);
2907 node = rb_next(&cache->cache_node);
2908 btrfs_put_block_group(cache);
2910 cache = rb_entry(node, struct btrfs_block_group_cache,
2912 btrfs_get_block_group(cache);
2915 spin_unlock(&root->fs_info->block_group_cache_lock);
2919 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2920 struct btrfs_trans_handle *trans,
2921 struct btrfs_path *path)
2923 struct btrfs_root *root = block_group->fs_info->tree_root;
2924 struct inode *inode = NULL;
2926 int dcs = BTRFS_DC_ERROR;
2932 * If this block group is smaller than 100 megs don't bother caching the
2935 if (block_group->key.offset < (100 * 1024 * 1024)) {
2936 spin_lock(&block_group->lock);
2937 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2938 spin_unlock(&block_group->lock);
2943 inode = lookup_free_space_inode(root, block_group, path);
2944 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2945 ret = PTR_ERR(inode);
2946 btrfs_release_path(path);
2950 if (IS_ERR(inode)) {
2954 if (block_group->ro)
2957 ret = create_free_space_inode(root, trans, block_group, path);
2963 /* We've already setup this transaction, go ahead and exit */
2964 if (block_group->cache_generation == trans->transid &&
2965 i_size_read(inode)) {
2966 dcs = BTRFS_DC_SETUP;
2971 * We want to set the generation to 0, that way if anything goes wrong
2972 * from here on out we know not to trust this cache when we load up next
2975 BTRFS_I(inode)->generation = 0;
2976 ret = btrfs_update_inode(trans, root, inode);
2979 if (i_size_read(inode) > 0) {
2980 ret = btrfs_truncate_free_space_cache(root, trans, path,
2986 spin_lock(&block_group->lock);
2987 if (block_group->cached != BTRFS_CACHE_FINISHED ||
2988 !btrfs_test_opt(root, SPACE_CACHE)) {
2990 * don't bother trying to write stuff out _if_
2991 * a) we're not cached,
2992 * b) we're with nospace_cache mount option.
2994 dcs = BTRFS_DC_WRITTEN;
2995 spin_unlock(&block_group->lock);
2998 spin_unlock(&block_group->lock);
3001 * Try to preallocate enough space based on how big the block group is.
3002 * Keep in mind this has to include any pinned space which could end up
3003 * taking up quite a bit since it's not folded into the other space
3006 num_pages = (int)div64_u64(block_group->key.offset, 256 * 1024 * 1024);
3011 num_pages *= PAGE_CACHE_SIZE;
3013 ret = btrfs_check_data_free_space(inode, num_pages);
3017 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
3018 num_pages, num_pages,
3021 dcs = BTRFS_DC_SETUP;
3022 btrfs_free_reserved_data_space(inode, num_pages);
3027 btrfs_release_path(path);
3029 spin_lock(&block_group->lock);
3030 if (!ret && dcs == BTRFS_DC_SETUP)
3031 block_group->cache_generation = trans->transid;
3032 block_group->disk_cache_state = dcs;
3033 spin_unlock(&block_group->lock);
3038 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
3039 struct btrfs_root *root)
3041 struct btrfs_block_group_cache *cache;
3043 struct btrfs_path *path;
3046 path = btrfs_alloc_path();
3052 cache = btrfs_lookup_first_block_group(root->fs_info, last);
3054 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
3056 cache = next_block_group(root, cache);
3064 err = cache_save_setup(cache, trans, path);
3065 last = cache->key.objectid + cache->key.offset;
3066 btrfs_put_block_group(cache);
3071 err = btrfs_run_delayed_refs(trans, root,
3073 if (err) /* File system offline */
3077 cache = btrfs_lookup_first_block_group(root->fs_info, last);
3079 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
3080 btrfs_put_block_group(cache);
3086 cache = next_block_group(root, cache);
3095 if (cache->disk_cache_state == BTRFS_DC_SETUP)
3096 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
3098 last = cache->key.objectid + cache->key.offset;
3100 err = write_one_cache_group(trans, root, path, cache);
3101 if (err) /* File system offline */
3104 btrfs_put_block_group(cache);
3109 * I don't think this is needed since we're just marking our
3110 * preallocated extent as written, but just in case it can't
3114 err = btrfs_run_delayed_refs(trans, root,
3116 if (err) /* File system offline */
3120 cache = btrfs_lookup_first_block_group(root->fs_info, last);
3123 * Really this shouldn't happen, but it could if we
3124 * couldn't write the entire preallocated extent and
3125 * splitting the extent resulted in a new block.
3128 btrfs_put_block_group(cache);
3131 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
3133 cache = next_block_group(root, cache);
3142 err = btrfs_write_out_cache(root, trans, cache, path);
3145 * If we didn't have an error then the cache state is still
3146 * NEED_WRITE, so we can set it to WRITTEN.
3148 if (!err && cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
3149 cache->disk_cache_state = BTRFS_DC_WRITTEN;
3150 last = cache->key.objectid + cache->key.offset;
3151 btrfs_put_block_group(cache);
3155 btrfs_free_path(path);
3159 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
3161 struct btrfs_block_group_cache *block_group;
3164 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
3165 if (!block_group || block_group->ro)
3168 btrfs_put_block_group(block_group);
3172 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
3173 u64 total_bytes, u64 bytes_used,
3174 struct btrfs_space_info **space_info)
3176 struct btrfs_space_info *found;
3180 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3181 BTRFS_BLOCK_GROUP_RAID10))
3186 found = __find_space_info(info, flags);
3188 spin_lock(&found->lock);
3189 found->total_bytes += total_bytes;
3190 found->disk_total += total_bytes * factor;
3191 found->bytes_used += bytes_used;
3192 found->disk_used += bytes_used * factor;
3194 spin_unlock(&found->lock);
3195 *space_info = found;
3198 found = kzalloc(sizeof(*found), GFP_NOFS);
3202 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3203 INIT_LIST_HEAD(&found->block_groups[i]);
3204 init_rwsem(&found->groups_sem);
3205 spin_lock_init(&found->lock);
3206 found->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
3207 found->total_bytes = total_bytes;
3208 found->disk_total = total_bytes * factor;
3209 found->bytes_used = bytes_used;
3210 found->disk_used = bytes_used * factor;
3211 found->bytes_pinned = 0;
3212 found->bytes_reserved = 0;
3213 found->bytes_readonly = 0;
3214 found->bytes_may_use = 0;
3216 found->force_alloc = CHUNK_ALLOC_NO_FORCE;
3217 found->chunk_alloc = 0;
3219 init_waitqueue_head(&found->wait);
3220 *space_info = found;
3221 list_add_rcu(&found->list, &info->space_info);
3222 if (flags & BTRFS_BLOCK_GROUP_DATA)
3223 info->data_sinfo = found;
3227 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3229 u64 extra_flags = chunk_to_extended(flags) &
3230 BTRFS_EXTENDED_PROFILE_MASK;
3232 if (flags & BTRFS_BLOCK_GROUP_DATA)
3233 fs_info->avail_data_alloc_bits |= extra_flags;
3234 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3235 fs_info->avail_metadata_alloc_bits |= extra_flags;
3236 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3237 fs_info->avail_system_alloc_bits |= extra_flags;
3241 * returns target flags in extended format or 0 if restripe for this
3242 * chunk_type is not in progress
3244 * should be called with either volume_mutex or balance_lock held
3246 static u64 get_restripe_target(struct btrfs_fs_info *fs_info, u64 flags)
3248 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3254 if (flags & BTRFS_BLOCK_GROUP_DATA &&
3255 bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3256 target = BTRFS_BLOCK_GROUP_DATA | bctl->data.target;
3257 } else if (flags & BTRFS_BLOCK_GROUP_SYSTEM &&
3258 bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3259 target = BTRFS_BLOCK_GROUP_SYSTEM | bctl->sys.target;
3260 } else if (flags & BTRFS_BLOCK_GROUP_METADATA &&
3261 bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3262 target = BTRFS_BLOCK_GROUP_METADATA | bctl->meta.target;
3269 * @flags: available profiles in extended format (see ctree.h)
3271 * Returns reduced profile in chunk format. If profile changing is in
3272 * progress (either running or paused) picks the target profile (if it's
3273 * already available), otherwise falls back to plain reducing.
3275 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3278 * we add in the count of missing devices because we want
3279 * to make sure that any RAID levels on a degraded FS
3280 * continue to be honored.
3282 u64 num_devices = root->fs_info->fs_devices->rw_devices +
3283 root->fs_info->fs_devices->missing_devices;
3287 * see if restripe for this chunk_type is in progress, if so
3288 * try to reduce to the target profile
3290 spin_lock(&root->fs_info->balance_lock);
3291 target = get_restripe_target(root->fs_info, flags);
3293 /* pick target profile only if it's already available */
3294 if ((flags & target) & BTRFS_EXTENDED_PROFILE_MASK) {
3295 spin_unlock(&root->fs_info->balance_lock);
3296 return extended_to_chunk(target);
3299 spin_unlock(&root->fs_info->balance_lock);
3301 if (num_devices == 1)
3302 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3303 if (num_devices < 4)
3304 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3306 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3307 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3308 BTRFS_BLOCK_GROUP_RAID10))) {
3309 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3312 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3313 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3314 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3317 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3318 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3319 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3320 (flags & BTRFS_BLOCK_GROUP_DUP))) {
3321 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3324 return extended_to_chunk(flags);
3327 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3329 if (flags & BTRFS_BLOCK_GROUP_DATA)
3330 flags |= root->fs_info->avail_data_alloc_bits;
3331 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3332 flags |= root->fs_info->avail_system_alloc_bits;
3333 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3334 flags |= root->fs_info->avail_metadata_alloc_bits;
3336 return btrfs_reduce_alloc_profile(root, flags);
3339 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3344 flags = BTRFS_BLOCK_GROUP_DATA;
3345 else if (root == root->fs_info->chunk_root)
3346 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3348 flags = BTRFS_BLOCK_GROUP_METADATA;
3350 return get_alloc_profile(root, flags);
3354 * This will check the space that the inode allocates from to make sure we have
3355 * enough space for bytes.
3357 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3359 struct btrfs_space_info *data_sinfo;
3360 struct btrfs_root *root = BTRFS_I(inode)->root;
3361 struct btrfs_fs_info *fs_info = root->fs_info;
3363 int ret = 0, committed = 0, alloc_chunk = 1;
3365 /* make sure bytes are sectorsize aligned */
3366 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3368 if (root == root->fs_info->tree_root ||
3369 BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID) {
3374 data_sinfo = fs_info->data_sinfo;
3379 /* make sure we have enough space to handle the data first */
3380 spin_lock(&data_sinfo->lock);
3381 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3382 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3383 data_sinfo->bytes_may_use;
3385 if (used + bytes > data_sinfo->total_bytes) {
3386 struct btrfs_trans_handle *trans;
3389 * if we don't have enough free bytes in this space then we need
3390 * to alloc a new chunk.
3392 if (!data_sinfo->full && alloc_chunk) {
3395 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
3396 spin_unlock(&data_sinfo->lock);
3398 alloc_target = btrfs_get_alloc_profile(root, 1);
3399 trans = btrfs_join_transaction(root);
3401 return PTR_ERR(trans);
3403 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3405 CHUNK_ALLOC_NO_FORCE);
3406 btrfs_end_transaction(trans, root);
3415 data_sinfo = fs_info->data_sinfo;
3421 * If we have less pinned bytes than we want to allocate then
3422 * don't bother committing the transaction, it won't help us.
3424 if (data_sinfo->bytes_pinned < bytes)
3426 spin_unlock(&data_sinfo->lock);
3428 /* commit the current transaction and try again */
3431 !atomic_read(&root->fs_info->open_ioctl_trans)) {
3433 trans = btrfs_join_transaction(root);
3435 return PTR_ERR(trans);
3436 ret = btrfs_commit_transaction(trans, root);
3444 data_sinfo->bytes_may_use += bytes;
3445 trace_btrfs_space_reservation(root->fs_info, "space_info",
3446 data_sinfo->flags, bytes, 1);
3447 spin_unlock(&data_sinfo->lock);
3453 * Called if we need to clear a data reservation for this inode.
3455 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3457 struct btrfs_root *root = BTRFS_I(inode)->root;
3458 struct btrfs_space_info *data_sinfo;
3460 /* make sure bytes are sectorsize aligned */
3461 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3463 data_sinfo = root->fs_info->data_sinfo;
3464 spin_lock(&data_sinfo->lock);
3465 data_sinfo->bytes_may_use -= bytes;
3466 trace_btrfs_space_reservation(root->fs_info, "space_info",
3467 data_sinfo->flags, bytes, 0);
3468 spin_unlock(&data_sinfo->lock);
3471 static void force_metadata_allocation(struct btrfs_fs_info *info)
3473 struct list_head *head = &info->space_info;
3474 struct btrfs_space_info *found;
3477 list_for_each_entry_rcu(found, head, list) {
3478 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3479 found->force_alloc = CHUNK_ALLOC_FORCE;
3484 static int should_alloc_chunk(struct btrfs_root *root,
3485 struct btrfs_space_info *sinfo, int force)
3487 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3488 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3489 u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
3492 if (force == CHUNK_ALLOC_FORCE)
3496 * We need to take into account the global rsv because for all intents
3497 * and purposes it's used space. Don't worry about locking the
3498 * global_rsv, it doesn't change except when the transaction commits.
3500 if (sinfo->flags & BTRFS_BLOCK_GROUP_METADATA)
3501 num_allocated += global_rsv->size;
3504 * in limited mode, we want to have some free space up to
3505 * about 1% of the FS size.
3507 if (force == CHUNK_ALLOC_LIMITED) {
3508 thresh = btrfs_super_total_bytes(root->fs_info->super_copy);
3509 thresh = max_t(u64, 64 * 1024 * 1024,
3510 div_factor_fine(thresh, 1));
3512 if (num_bytes - num_allocated < thresh)
3516 if (num_allocated + 2 * 1024 * 1024 < div_factor(num_bytes, 8))
3521 static u64 get_system_chunk_thresh(struct btrfs_root *root, u64 type)
3525 if (type & BTRFS_BLOCK_GROUP_RAID10 ||
3526 type & BTRFS_BLOCK_GROUP_RAID0)
3527 num_dev = root->fs_info->fs_devices->rw_devices;
3528 else if (type & BTRFS_BLOCK_GROUP_RAID1)
3531 num_dev = 1; /* DUP or single */
3533 /* metadata for updaing devices and chunk tree */
3534 return btrfs_calc_trans_metadata_size(root, num_dev + 1);
3537 static void check_system_chunk(struct btrfs_trans_handle *trans,
3538 struct btrfs_root *root, u64 type)
3540 struct btrfs_space_info *info;
3544 info = __find_space_info(root->fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3545 spin_lock(&info->lock);
3546 left = info->total_bytes - info->bytes_used - info->bytes_pinned -
3547 info->bytes_reserved - info->bytes_readonly;
3548 spin_unlock(&info->lock);
3550 thresh = get_system_chunk_thresh(root, type);
3551 if (left < thresh && btrfs_test_opt(root, ENOSPC_DEBUG)) {
3552 printk(KERN_INFO "left=%llu, need=%llu, flags=%llu\n",
3553 left, thresh, type);
3554 dump_space_info(info, 0, 0);
3557 if (left < thresh) {
3560 flags = btrfs_get_alloc_profile(root->fs_info->chunk_root, 0);
3561 btrfs_alloc_chunk(trans, root, flags);
3565 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3566 struct btrfs_root *extent_root, u64 flags, int force)
3568 struct btrfs_space_info *space_info;
3569 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3570 int wait_for_alloc = 0;
3573 space_info = __find_space_info(extent_root->fs_info, flags);
3575 ret = update_space_info(extent_root->fs_info, flags,
3577 BUG_ON(ret); /* -ENOMEM */
3579 BUG_ON(!space_info); /* Logic error */
3582 spin_lock(&space_info->lock);
3583 if (force < space_info->force_alloc)
3584 force = space_info->force_alloc;
3585 if (space_info->full) {
3586 spin_unlock(&space_info->lock);
3590 if (!should_alloc_chunk(extent_root, space_info, force)) {
3591 spin_unlock(&space_info->lock);
3593 } else if (space_info->chunk_alloc) {
3596 space_info->chunk_alloc = 1;
3599 spin_unlock(&space_info->lock);
3601 mutex_lock(&fs_info->chunk_mutex);
3604 * The chunk_mutex is held throughout the entirety of a chunk
3605 * allocation, so once we've acquired the chunk_mutex we know that the
3606 * other guy is done and we need to recheck and see if we should
3609 if (wait_for_alloc) {
3610 mutex_unlock(&fs_info->chunk_mutex);
3616 * If we have mixed data/metadata chunks we want to make sure we keep
3617 * allocating mixed chunks instead of individual chunks.
3619 if (btrfs_mixed_space_info(space_info))
3620 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3623 * if we're doing a data chunk, go ahead and make sure that
3624 * we keep a reasonable number of metadata chunks allocated in the
3627 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3628 fs_info->data_chunk_allocations++;
3629 if (!(fs_info->data_chunk_allocations %
3630 fs_info->metadata_ratio))
3631 force_metadata_allocation(fs_info);
3635 * Check if we have enough space in SYSTEM chunk because we may need
3636 * to update devices.
3638 check_system_chunk(trans, extent_root, flags);
3640 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3641 if (ret < 0 && ret != -ENOSPC)
3644 spin_lock(&space_info->lock);
3646 space_info->full = 1;
3650 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3651 space_info->chunk_alloc = 0;
3652 spin_unlock(&space_info->lock);
3654 mutex_unlock(&fs_info->chunk_mutex);
3658 static int can_overcommit(struct btrfs_root *root,
3659 struct btrfs_space_info *space_info, u64 bytes,
3660 enum btrfs_reserve_flush_enum flush)
3662 u64 profile = btrfs_get_alloc_profile(root, 0);
3666 used = space_info->bytes_used + space_info->bytes_reserved +
3667 space_info->bytes_pinned + space_info->bytes_readonly +
3668 space_info->bytes_may_use;
3670 spin_lock(&root->fs_info->free_chunk_lock);
3671 avail = root->fs_info->free_chunk_space;
3672 spin_unlock(&root->fs_info->free_chunk_lock);
3675 * If we have dup, raid1 or raid10 then only half of the free
3676 * space is actually useable.
3678 if (profile & (BTRFS_BLOCK_GROUP_DUP |
3679 BTRFS_BLOCK_GROUP_RAID1 |
3680 BTRFS_BLOCK_GROUP_RAID10))
3684 * If we aren't flushing all things, let us overcommit up to
3685 * 1/2th of the space. If we can flush, don't let us overcommit
3686 * too much, let it overcommit up to 1/8 of the space.
3688 if (flush == BTRFS_RESERVE_FLUSH_ALL)
3693 if (used + bytes < space_info->total_bytes + avail)
3698 static inline int writeback_inodes_sb_nr_if_idle_safe(struct super_block *sb,
3699 unsigned long nr_pages,
3700 enum wb_reason reason)
3702 /* the flusher is dealing with the dirty inodes now. */
3703 if (writeback_in_progress(sb->s_bdi))
3706 if (down_read_trylock(&sb->s_umount)) {
3707 writeback_inodes_sb_nr(sb, nr_pages, reason);
3708 up_read(&sb->s_umount);
3715 void btrfs_writeback_inodes_sb_nr(struct btrfs_root *root,
3716 unsigned long nr_pages)
3718 struct super_block *sb = root->fs_info->sb;
3721 /* If we can not start writeback, just sync all the delalloc file. */
3722 started = writeback_inodes_sb_nr_if_idle_safe(sb, nr_pages,
3723 WB_REASON_FS_FREE_SPACE);
3726 * We needn't worry the filesystem going from r/w to r/o though
3727 * we don't acquire ->s_umount mutex, because the filesystem
3728 * should guarantee the delalloc inodes list be empty after
3729 * the filesystem is readonly(all dirty pages are written to
3732 btrfs_start_delalloc_inodes(root, 0);
3733 btrfs_wait_ordered_extents(root, 0);
3738 * shrink metadata reservation for delalloc
3740 static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
3743 struct btrfs_block_rsv *block_rsv;
3744 struct btrfs_space_info *space_info;
3745 struct btrfs_trans_handle *trans;
3749 unsigned long nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3751 enum btrfs_reserve_flush_enum flush;
3753 trans = (struct btrfs_trans_handle *)current->journal_info;
3754 block_rsv = &root->fs_info->delalloc_block_rsv;
3755 space_info = block_rsv->space_info;
3758 delalloc_bytes = root->fs_info->delalloc_bytes;
3759 if (delalloc_bytes == 0) {
3762 btrfs_wait_ordered_extents(root, 0);
3766 while (delalloc_bytes && loops < 3) {
3767 max_reclaim = min(delalloc_bytes, to_reclaim);
3768 nr_pages = max_reclaim >> PAGE_CACHE_SHIFT;
3769 btrfs_writeback_inodes_sb_nr(root, nr_pages);
3771 * We need to wait for the async pages to actually start before
3774 wait_event(root->fs_info->async_submit_wait,
3775 !atomic_read(&root->fs_info->async_delalloc_pages));
3778 flush = BTRFS_RESERVE_FLUSH_ALL;
3780 flush = BTRFS_RESERVE_NO_FLUSH;
3781 spin_lock(&space_info->lock);
3782 if (can_overcommit(root, space_info, orig, flush)) {
3783 spin_unlock(&space_info->lock);
3786 spin_unlock(&space_info->lock);
3789 if (wait_ordered && !trans) {
3790 btrfs_wait_ordered_extents(root, 0);
3792 time_left = schedule_timeout_killable(1);
3797 delalloc_bytes = root->fs_info->delalloc_bytes;
3802 * maybe_commit_transaction - possibly commit the transaction if its ok to
3803 * @root - the root we're allocating for
3804 * @bytes - the number of bytes we want to reserve
3805 * @force - force the commit
3807 * This will check to make sure that committing the transaction will actually
3808 * get us somewhere and then commit the transaction if it does. Otherwise it
3809 * will return -ENOSPC.
3811 static int may_commit_transaction(struct btrfs_root *root,
3812 struct btrfs_space_info *space_info,
3813 u64 bytes, int force)
3815 struct btrfs_block_rsv *delayed_rsv = &root->fs_info->delayed_block_rsv;
3816 struct btrfs_trans_handle *trans;
3818 trans = (struct btrfs_trans_handle *)current->journal_info;
3825 /* See if there is enough pinned space to make this reservation */
3826 spin_lock(&space_info->lock);
3827 if (space_info->bytes_pinned >= bytes) {
3828 spin_unlock(&space_info->lock);
3831 spin_unlock(&space_info->lock);
3834 * See if there is some space in the delayed insertion reservation for
3837 if (space_info != delayed_rsv->space_info)
3840 spin_lock(&space_info->lock);
3841 spin_lock(&delayed_rsv->lock);
3842 if (space_info->bytes_pinned + delayed_rsv->size < bytes) {
3843 spin_unlock(&delayed_rsv->lock);
3844 spin_unlock(&space_info->lock);
3847 spin_unlock(&delayed_rsv->lock);
3848 spin_unlock(&space_info->lock);
3851 trans = btrfs_join_transaction(root);
3855 return btrfs_commit_transaction(trans, root);
3859 FLUSH_DELAYED_ITEMS_NR = 1,
3860 FLUSH_DELAYED_ITEMS = 2,
3862 FLUSH_DELALLOC_WAIT = 4,
3867 static int flush_space(struct btrfs_root *root,
3868 struct btrfs_space_info *space_info, u64 num_bytes,
3869 u64 orig_bytes, int state)
3871 struct btrfs_trans_handle *trans;
3876 case FLUSH_DELAYED_ITEMS_NR:
3877 case FLUSH_DELAYED_ITEMS:
3878 if (state == FLUSH_DELAYED_ITEMS_NR) {
3879 u64 bytes = btrfs_calc_trans_metadata_size(root, 1);
3881 nr = (int)div64_u64(num_bytes, bytes);
3888 trans = btrfs_join_transaction(root);
3889 if (IS_ERR(trans)) {
3890 ret = PTR_ERR(trans);
3893 ret = btrfs_run_delayed_items_nr(trans, root, nr);
3894 btrfs_end_transaction(trans, root);
3896 case FLUSH_DELALLOC:
3897 case FLUSH_DELALLOC_WAIT:
3898 shrink_delalloc(root, num_bytes, orig_bytes,
3899 state == FLUSH_DELALLOC_WAIT);
3902 trans = btrfs_join_transaction(root);
3903 if (IS_ERR(trans)) {
3904 ret = PTR_ERR(trans);
3907 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3908 btrfs_get_alloc_profile(root, 0),
3909 CHUNK_ALLOC_NO_FORCE);
3910 btrfs_end_transaction(trans, root);
3915 ret = may_commit_transaction(root, space_info, orig_bytes, 0);
3925 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
3926 * @root - the root we're allocating for
3927 * @block_rsv - the block_rsv we're allocating for
3928 * @orig_bytes - the number of bytes we want
3929 * @flush - wether or not we can flush to make our reservation
3931 * This will reserve orgi_bytes number of bytes from the space info associated
3932 * with the block_rsv. If there is not enough space it will make an attempt to
3933 * flush out space to make room. It will do this by flushing delalloc if
3934 * possible or committing the transaction. If flush is 0 then no attempts to
3935 * regain reservations will be made and this will fail if there is not enough
3938 static int reserve_metadata_bytes(struct btrfs_root *root,
3939 struct btrfs_block_rsv *block_rsv,
3941 enum btrfs_reserve_flush_enum flush)
3943 struct btrfs_space_info *space_info = block_rsv->space_info;
3945 u64 num_bytes = orig_bytes;
3946 int flush_state = FLUSH_DELAYED_ITEMS_NR;
3948 bool flushing = false;
3952 spin_lock(&space_info->lock);
3954 * We only want to wait if somebody other than us is flushing and we
3955 * are actually allowed to flush all things.
3957 while (flush == BTRFS_RESERVE_FLUSH_ALL && !flushing &&
3958 space_info->flush) {
3959 spin_unlock(&space_info->lock);
3961 * If we have a trans handle we can't wait because the flusher
3962 * may have to commit the transaction, which would mean we would
3963 * deadlock since we are waiting for the flusher to finish, but
3964 * hold the current transaction open.
3966 if (current->journal_info)
3968 ret = wait_event_killable(space_info->wait, !space_info->flush);
3969 /* Must have been killed, return */
3973 spin_lock(&space_info->lock);
3977 used = space_info->bytes_used + space_info->bytes_reserved +
3978 space_info->bytes_pinned + space_info->bytes_readonly +
3979 space_info->bytes_may_use;
3982 * The idea here is that we've not already over-reserved the block group
3983 * then we can go ahead and save our reservation first and then start
3984 * flushing if we need to. Otherwise if we've already overcommitted
3985 * lets start flushing stuff first and then come back and try to make
3988 if (used <= space_info->total_bytes) {
3989 if (used + orig_bytes <= space_info->total_bytes) {
3990 space_info->bytes_may_use += orig_bytes;
3991 trace_btrfs_space_reservation(root->fs_info,
3992 "space_info", space_info->flags, orig_bytes, 1);
3996 * Ok set num_bytes to orig_bytes since we aren't
3997 * overocmmitted, this way we only try and reclaim what
4000 num_bytes = orig_bytes;
4004 * Ok we're over committed, set num_bytes to the overcommitted
4005 * amount plus the amount of bytes that we need for this
4008 num_bytes = used - space_info->total_bytes +
4012 if (ret && can_overcommit(root, space_info, orig_bytes, flush)) {
4013 space_info->bytes_may_use += orig_bytes;
4014 trace_btrfs_space_reservation(root->fs_info, "space_info",
4015 space_info->flags, orig_bytes,
4021 * Couldn't make our reservation, save our place so while we're trying
4022 * to reclaim space we can actually use it instead of somebody else
4023 * stealing it from us.
4025 * We make the other tasks wait for the flush only when we can flush
4028 if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
4030 space_info->flush = 1;
4033 spin_unlock(&space_info->lock);
4035 if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
4038 ret = flush_space(root, space_info, num_bytes, orig_bytes,
4043 * If we are FLUSH_LIMIT, we can not flush delalloc, or the deadlock
4044 * would happen. So skip delalloc flush.
4046 if (flush == BTRFS_RESERVE_FLUSH_LIMIT &&
4047 (flush_state == FLUSH_DELALLOC ||
4048 flush_state == FLUSH_DELALLOC_WAIT))
4049 flush_state = ALLOC_CHUNK;
4053 else if (flush == BTRFS_RESERVE_FLUSH_LIMIT &&
4054 flush_state < COMMIT_TRANS)
4056 else if (flush == BTRFS_RESERVE_FLUSH_ALL &&
4057 flush_state <= COMMIT_TRANS)
4062 spin_lock(&space_info->lock);
4063 space_info->flush = 0;
4064 wake_up_all(&space_info->wait);
4065 spin_unlock(&space_info->lock);
4070 static struct btrfs_block_rsv *get_block_rsv(
4071 const struct btrfs_trans_handle *trans,
4072 const struct btrfs_root *root)
4074 struct btrfs_block_rsv *block_rsv = NULL;
4077 block_rsv = trans->block_rsv;
4079 if (root == root->fs_info->csum_root && trans->adding_csums)
4080 block_rsv = trans->block_rsv;
4083 block_rsv = root->block_rsv;
4086 block_rsv = &root->fs_info->empty_block_rsv;
4091 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
4095 spin_lock(&block_rsv->lock);
4096 if (block_rsv->reserved >= num_bytes) {
4097 block_rsv->reserved -= num_bytes;
4098 if (block_rsv->reserved < block_rsv->size)
4099 block_rsv->full = 0;
4102 spin_unlock(&block_rsv->lock);
4106 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
4107 u64 num_bytes, int update_size)
4109 spin_lock(&block_rsv->lock);
4110 block_rsv->reserved += num_bytes;
4112 block_rsv->size += num_bytes;
4113 else if (block_rsv->reserved >= block_rsv->size)
4114 block_rsv->full = 1;
4115 spin_unlock(&block_rsv->lock);
4118 static void block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
4119 struct btrfs_block_rsv *block_rsv,
4120 struct btrfs_block_rsv *dest, u64 num_bytes)
4122 struct btrfs_space_info *space_info = block_rsv->space_info;
4124 spin_lock(&block_rsv->lock);
4125 if (num_bytes == (u64)-1)
4126 num_bytes = block_rsv->size;
4127 block_rsv->size -= num_bytes;
4128 if (block_rsv->reserved >= block_rsv->size) {
4129 num_bytes = block_rsv->reserved - block_rsv->size;
4130 block_rsv->reserved = block_rsv->size;
4131 block_rsv->full = 1;
4135 spin_unlock(&block_rsv->lock);
4137 if (num_bytes > 0) {
4139 spin_lock(&dest->lock);
4143 bytes_to_add = dest->size - dest->reserved;
4144 bytes_to_add = min(num_bytes, bytes_to_add);
4145 dest->reserved += bytes_to_add;
4146 if (dest->reserved >= dest->size)
4148 num_bytes -= bytes_to_add;
4150 spin_unlock(&dest->lock);
4153 spin_lock(&space_info->lock);
4154 space_info->bytes_may_use -= num_bytes;
4155 trace_btrfs_space_reservation(fs_info, "space_info",
4156 space_info->flags, num_bytes, 0);
4157 space_info->reservation_progress++;
4158 spin_unlock(&space_info->lock);
4163 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
4164 struct btrfs_block_rsv *dst, u64 num_bytes)
4168 ret = block_rsv_use_bytes(src, num_bytes);
4172 block_rsv_add_bytes(dst, num_bytes, 1);
4176 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
4178 memset(rsv, 0, sizeof(*rsv));
4179 spin_lock_init(&rsv->lock);
4183 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root,
4184 unsigned short type)
4186 struct btrfs_block_rsv *block_rsv;
4187 struct btrfs_fs_info *fs_info = root->fs_info;
4189 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
4193 btrfs_init_block_rsv(block_rsv, type);
4194 block_rsv->space_info = __find_space_info(fs_info,
4195 BTRFS_BLOCK_GROUP_METADATA);
4199 void btrfs_free_block_rsv(struct btrfs_root *root,
4200 struct btrfs_block_rsv *rsv)
4204 btrfs_block_rsv_release(root, rsv, (u64)-1);
4208 int btrfs_block_rsv_add(struct btrfs_root *root,
4209 struct btrfs_block_rsv *block_rsv, u64 num_bytes,
4210 enum btrfs_reserve_flush_enum flush)
4217 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
4219 block_rsv_add_bytes(block_rsv, num_bytes, 1);
4226 int btrfs_block_rsv_check(struct btrfs_root *root,
4227 struct btrfs_block_rsv *block_rsv, int min_factor)
4235 spin_lock(&block_rsv->lock);
4236 num_bytes = div_factor(block_rsv->size, min_factor);
4237 if (block_rsv->reserved >= num_bytes)
4239 spin_unlock(&block_rsv->lock);
4244 int btrfs_block_rsv_refill(struct btrfs_root *root,
4245 struct btrfs_block_rsv *block_rsv, u64 min_reserved,
4246 enum btrfs_reserve_flush_enum flush)
4254 spin_lock(&block_rsv->lock);
4255 num_bytes = min_reserved;
4256 if (block_rsv->reserved >= num_bytes)
4259 num_bytes -= block_rsv->reserved;
4260 spin_unlock(&block_rsv->lock);
4265 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
4267 block_rsv_add_bytes(block_rsv, num_bytes, 0);
4274 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
4275 struct btrfs_block_rsv *dst_rsv,
4278 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
4281 void btrfs_block_rsv_release(struct btrfs_root *root,
4282 struct btrfs_block_rsv *block_rsv,
4285 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
4286 if (global_rsv->full || global_rsv == block_rsv ||
4287 block_rsv->space_info != global_rsv->space_info)
4289 block_rsv_release_bytes(root->fs_info, block_rsv, global_rsv,
4294 * helper to calculate size of global block reservation.
4295 * the desired value is sum of space used by extent tree,
4296 * checksum tree and root tree
4298 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
4300 struct btrfs_space_info *sinfo;
4304 int csum_size = btrfs_super_csum_size(fs_info->super_copy);
4306 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
4307 spin_lock(&sinfo->lock);
4308 data_used = sinfo->bytes_used;
4309 spin_unlock(&sinfo->lock);
4311 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4312 spin_lock(&sinfo->lock);
4313 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
4315 meta_used = sinfo->bytes_used;
4316 spin_unlock(&sinfo->lock);
4318 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
4320 num_bytes += div64_u64(data_used + meta_used, 50);
4322 if (num_bytes * 3 > meta_used)
4323 num_bytes = div64_u64(meta_used, 3);
4325 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
4328 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
4330 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4331 struct btrfs_space_info *sinfo = block_rsv->space_info;
4334 num_bytes = calc_global_metadata_size(fs_info);
4336 spin_lock(&sinfo->lock);
4337 spin_lock(&block_rsv->lock);
4339 block_rsv->size = num_bytes;
4341 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
4342 sinfo->bytes_reserved + sinfo->bytes_readonly +
4343 sinfo->bytes_may_use;
4345 if (sinfo->total_bytes > num_bytes) {
4346 num_bytes = sinfo->total_bytes - num_bytes;
4347 block_rsv->reserved += num_bytes;
4348 sinfo->bytes_may_use += num_bytes;
4349 trace_btrfs_space_reservation(fs_info, "space_info",
4350 sinfo->flags, num_bytes, 1);
4353 if (block_rsv->reserved >= block_rsv->size) {
4354 num_bytes = block_rsv->reserved - block_rsv->size;
4355 sinfo->bytes_may_use -= num_bytes;
4356 trace_btrfs_space_reservation(fs_info, "space_info",
4357 sinfo->flags, num_bytes, 0);
4358 sinfo->reservation_progress++;
4359 block_rsv->reserved = block_rsv->size;
4360 block_rsv->full = 1;
4363 spin_unlock(&block_rsv->lock);
4364 spin_unlock(&sinfo->lock);
4367 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
4369 struct btrfs_space_info *space_info;
4371 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4372 fs_info->chunk_block_rsv.space_info = space_info;
4374 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4375 fs_info->global_block_rsv.space_info = space_info;
4376 fs_info->delalloc_block_rsv.space_info = space_info;
4377 fs_info->trans_block_rsv.space_info = space_info;
4378 fs_info->empty_block_rsv.space_info = space_info;
4379 fs_info->delayed_block_rsv.space_info = space_info;
4381 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
4382 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
4383 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
4384 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
4385 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
4387 update_global_block_rsv(fs_info);
4390 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
4392 block_rsv_release_bytes(fs_info, &fs_info->global_block_rsv, NULL,
4394 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
4395 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
4396 WARN_ON(fs_info->trans_block_rsv.size > 0);
4397 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
4398 WARN_ON(fs_info->chunk_block_rsv.size > 0);
4399 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
4400 WARN_ON(fs_info->delayed_block_rsv.size > 0);
4401 WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
4404 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
4405 struct btrfs_root *root)
4407 if (!trans->block_rsv)
4410 if (!trans->bytes_reserved)
4413 trace_btrfs_space_reservation(root->fs_info, "transaction",
4414 trans->transid, trans->bytes_reserved, 0);
4415 btrfs_block_rsv_release(root, trans->block_rsv, trans->bytes_reserved);
4416 trans->bytes_reserved = 0;
4419 /* Can only return 0 or -ENOSPC */
4420 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
4421 struct inode *inode)
4423 struct btrfs_root *root = BTRFS_I(inode)->root;
4424 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
4425 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
4428 * We need to hold space in order to delete our orphan item once we've
4429 * added it, so this takes the reservation so we can release it later
4430 * when we are truly done with the orphan item.
4432 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
4433 trace_btrfs_space_reservation(root->fs_info, "orphan",
4434 btrfs_ino(inode), num_bytes, 1);
4435 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
4438 void btrfs_orphan_release_metadata(struct inode *inode)
4440 struct btrfs_root *root = BTRFS_I(inode)->root;
4441 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
4442 trace_btrfs_space_reservation(root->fs_info, "orphan",
4443 btrfs_ino(inode), num_bytes, 0);
4444 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
4447 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
4448 struct btrfs_pending_snapshot *pending)
4450 struct btrfs_root *root = pending->root;
4451 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
4452 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
4454 * two for root back/forward refs, two for directory entries,
4455 * one for root of the snapshot and one for parent inode.
4457 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 6);
4458 dst_rsv->space_info = src_rsv->space_info;
4459 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
4463 * drop_outstanding_extent - drop an outstanding extent
4464 * @inode: the inode we're dropping the extent for
4466 * This is called when we are freeing up an outstanding extent, either called
4467 * after an error or after an extent is written. This will return the number of
4468 * reserved extents that need to be freed. This must be called with
4469 * BTRFS_I(inode)->lock held.
4471 static unsigned drop_outstanding_extent(struct inode *inode)
4473 unsigned drop_inode_space = 0;
4474 unsigned dropped_extents = 0;
4476 BUG_ON(!BTRFS_I(inode)->outstanding_extents);
4477 BTRFS_I(inode)->outstanding_extents--;
4479 if (BTRFS_I(inode)->outstanding_extents == 0 &&
4480 test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
4481 &BTRFS_I(inode)->runtime_flags))
4482 drop_inode_space = 1;
4485 * If we have more or the same amount of outsanding extents than we have
4486 * reserved then we need to leave the reserved extents count alone.
4488 if (BTRFS_I(inode)->outstanding_extents >=
4489 BTRFS_I(inode)->reserved_extents)
4490 return drop_inode_space;
4492 dropped_extents = BTRFS_I(inode)->reserved_extents -
4493 BTRFS_I(inode)->outstanding_extents;
4494 BTRFS_I(inode)->reserved_extents -= dropped_extents;
4495 return dropped_extents + drop_inode_space;
4499 * calc_csum_metadata_size - return the amount of metada space that must be
4500 * reserved/free'd for the given bytes.
4501 * @inode: the inode we're manipulating
4502 * @num_bytes: the number of bytes in question
4503 * @reserve: 1 if we are reserving space, 0 if we are freeing space
4505 * This adjusts the number of csum_bytes in the inode and then returns the
4506 * correct amount of metadata that must either be reserved or freed. We
4507 * calculate how many checksums we can fit into one leaf and then divide the
4508 * number of bytes that will need to be checksumed by this value to figure out
4509 * how many checksums will be required. If we are adding bytes then the number
4510 * may go up and we will return the number of additional bytes that must be
4511 * reserved. If it is going down we will return the number of bytes that must
4514 * This must be called with BTRFS_I(inode)->lock held.
4516 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes,
4519 struct btrfs_root *root = BTRFS_I(inode)->root;
4521 int num_csums_per_leaf;
4525 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM &&
4526 BTRFS_I(inode)->csum_bytes == 0)
4529 old_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
4531 BTRFS_I(inode)->csum_bytes += num_bytes;
4533 BTRFS_I(inode)->csum_bytes -= num_bytes;
4534 csum_size = BTRFS_LEAF_DATA_SIZE(root) - sizeof(struct btrfs_item);
4535 num_csums_per_leaf = (int)div64_u64(csum_size,
4536 sizeof(struct btrfs_csum_item) +
4537 sizeof(struct btrfs_disk_key));
4538 num_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
4539 num_csums = num_csums + num_csums_per_leaf - 1;
4540 num_csums = num_csums / num_csums_per_leaf;
4542 old_csums = old_csums + num_csums_per_leaf - 1;
4543 old_csums = old_csums / num_csums_per_leaf;
4545 /* No change, no need to reserve more */
4546 if (old_csums == num_csums)
4550 return btrfs_calc_trans_metadata_size(root,
4551 num_csums - old_csums);
4553 return btrfs_calc_trans_metadata_size(root, old_csums - num_csums);
4556 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
4558 struct btrfs_root *root = BTRFS_I(inode)->root;
4559 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
4562 unsigned nr_extents = 0;
4563 int extra_reserve = 0;
4564 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
4566 bool delalloc_lock = true;
4568 /* If we are a free space inode we need to not flush since we will be in
4569 * the middle of a transaction commit. We also don't need the delalloc
4570 * mutex since we won't race with anybody. We need this mostly to make
4571 * lockdep shut its filthy mouth.
4573 if (btrfs_is_free_space_inode(inode)) {
4574 flush = BTRFS_RESERVE_NO_FLUSH;
4575 delalloc_lock = false;
4578 if (flush != BTRFS_RESERVE_NO_FLUSH &&
4579 btrfs_transaction_in_commit(root->fs_info))
4580 schedule_timeout(1);
4583 mutex_lock(&BTRFS_I(inode)->delalloc_mutex);
4585 num_bytes = ALIGN(num_bytes, root->sectorsize);
4587 spin_lock(&BTRFS_I(inode)->lock);
4588 BTRFS_I(inode)->outstanding_extents++;
4590 if (BTRFS_I(inode)->outstanding_extents >
4591 BTRFS_I(inode)->reserved_extents)
4592 nr_extents = BTRFS_I(inode)->outstanding_extents -
4593 BTRFS_I(inode)->reserved_extents;
4596 * Add an item to reserve for updating the inode when we complete the
4599 if (!test_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
4600 &BTRFS_I(inode)->runtime_flags)) {
4605 to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
4606 to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
4607 csum_bytes = BTRFS_I(inode)->csum_bytes;
4608 spin_unlock(&BTRFS_I(inode)->lock);
4610 if (root->fs_info->quota_enabled)
4611 ret = btrfs_qgroup_reserve(root, num_bytes +
4612 nr_extents * root->leafsize);
4615 * ret != 0 here means the qgroup reservation failed, we go straight to
4616 * the shared error handling then.
4619 ret = reserve_metadata_bytes(root, block_rsv,
4626 spin_lock(&BTRFS_I(inode)->lock);
4627 dropped = drop_outstanding_extent(inode);
4629 * If the inodes csum_bytes is the same as the original
4630 * csum_bytes then we know we haven't raced with any free()ers
4631 * so we can just reduce our inodes csum bytes and carry on.
4632 * Otherwise we have to do the normal free thing to account for
4633 * the case that the free side didn't free up its reserve
4634 * because of this outstanding reservation.
4636 if (BTRFS_I(inode)->csum_bytes == csum_bytes)
4637 calc_csum_metadata_size(inode, num_bytes, 0);
4639 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
4640 spin_unlock(&BTRFS_I(inode)->lock);
4642 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4645 btrfs_block_rsv_release(root, block_rsv, to_free);
4646 trace_btrfs_space_reservation(root->fs_info,
4651 if (root->fs_info->quota_enabled) {
4652 btrfs_qgroup_free(root, num_bytes +
4653 nr_extents * root->leafsize);
4656 mutex_unlock(&BTRFS_I(inode)->delalloc_mutex);
4660 spin_lock(&BTRFS_I(inode)->lock);
4661 if (extra_reserve) {
4662 set_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
4663 &BTRFS_I(inode)->runtime_flags);
4666 BTRFS_I(inode)->reserved_extents += nr_extents;
4667 spin_unlock(&BTRFS_I(inode)->lock);
4670 mutex_unlock(&BTRFS_I(inode)->delalloc_mutex);
4673 trace_btrfs_space_reservation(root->fs_info,"delalloc",
4674 btrfs_ino(inode), to_reserve, 1);
4675 block_rsv_add_bytes(block_rsv, to_reserve, 1);
4681 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
4682 * @inode: the inode to release the reservation for
4683 * @num_bytes: the number of bytes we're releasing
4685 * This will release the metadata reservation for an inode. This can be called
4686 * once we complete IO for a given set of bytes to release their metadata
4689 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4691 struct btrfs_root *root = BTRFS_I(inode)->root;
4695 num_bytes = ALIGN(num_bytes, root->sectorsize);
4696 spin_lock(&BTRFS_I(inode)->lock);
4697 dropped = drop_outstanding_extent(inode);
4699 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
4700 spin_unlock(&BTRFS_I(inode)->lock);
4702 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4704 trace_btrfs_space_reservation(root->fs_info, "delalloc",
4705 btrfs_ino(inode), to_free, 0);
4706 if (root->fs_info->quota_enabled) {
4707 btrfs_qgroup_free(root, num_bytes +
4708 dropped * root->leafsize);
4711 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4716 * btrfs_delalloc_reserve_space - reserve data and metadata space for delalloc
4717 * @inode: inode we're writing to
4718 * @num_bytes: the number of bytes we want to allocate
4720 * This will do the following things
4722 * o reserve space in the data space info for num_bytes
4723 * o reserve space in the metadata space info based on number of outstanding
4724 * extents and how much csums will be needed
4725 * o add to the inodes ->delalloc_bytes
4726 * o add it to the fs_info's delalloc inodes list.
4728 * This will return 0 for success and -ENOSPC if there is no space left.
4730 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4734 ret = btrfs_check_data_free_space(inode, num_bytes);
4738 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4740 btrfs_free_reserved_data_space(inode, num_bytes);
4748 * btrfs_delalloc_release_space - release data and metadata space for delalloc
4749 * @inode: inode we're releasing space for
4750 * @num_bytes: the number of bytes we want to free up
4752 * This must be matched with a call to btrfs_delalloc_reserve_space. This is
4753 * called in the case that we don't need the metadata AND data reservations
4754 * anymore. So if there is an error or we insert an inline extent.
4756 * This function will release the metadata space that was not used and will
4757 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
4758 * list if there are no delalloc bytes left.
4760 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4762 btrfs_delalloc_release_metadata(inode, num_bytes);
4763 btrfs_free_reserved_data_space(inode, num_bytes);
4766 static int update_block_group(struct btrfs_trans_handle *trans,
4767 struct btrfs_root *root,
4768 u64 bytenr, u64 num_bytes, int alloc)
4770 struct btrfs_block_group_cache *cache = NULL;
4771 struct btrfs_fs_info *info = root->fs_info;
4772 u64 total = num_bytes;
4777 /* block accounting for super block */
4778 spin_lock(&info->delalloc_lock);
4779 old_val = btrfs_super_bytes_used(info->super_copy);
4781 old_val += num_bytes;
4783 old_val -= num_bytes;
4784 btrfs_set_super_bytes_used(info->super_copy, old_val);
4785 spin_unlock(&info->delalloc_lock);
4788 cache = btrfs_lookup_block_group(info, bytenr);
4791 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4792 BTRFS_BLOCK_GROUP_RAID1 |
4793 BTRFS_BLOCK_GROUP_RAID10))
4798 * If this block group has free space cache written out, we
4799 * need to make sure to load it if we are removing space. This
4800 * is because we need the unpinning stage to actually add the
4801 * space back to the block group, otherwise we will leak space.
4803 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4804 cache_block_group(cache, trans, NULL, 1);
4806 byte_in_group = bytenr - cache->key.objectid;
4807 WARN_ON(byte_in_group > cache->key.offset);
4809 spin_lock(&cache->space_info->lock);
4810 spin_lock(&cache->lock);
4812 if (btrfs_test_opt(root, SPACE_CACHE) &&
4813 cache->disk_cache_state < BTRFS_DC_CLEAR)
4814 cache->disk_cache_state = BTRFS_DC_CLEAR;
4817 old_val = btrfs_block_group_used(&cache->item);
4818 num_bytes = min(total, cache->key.offset - byte_in_group);
4820 old_val += num_bytes;
4821 btrfs_set_block_group_used(&cache->item, old_val);
4822 cache->reserved -= num_bytes;
4823 cache->space_info->bytes_reserved -= num_bytes;
4824 cache->space_info->bytes_used += num_bytes;
4825 cache->space_info->disk_used += num_bytes * factor;
4826 spin_unlock(&cache->lock);
4827 spin_unlock(&cache->space_info->lock);
4829 old_val -= num_bytes;
4830 btrfs_set_block_group_used(&cache->item, old_val);
4831 cache->pinned += num_bytes;
4832 cache->space_info->bytes_pinned += num_bytes;
4833 cache->space_info->bytes_used -= num_bytes;
4834 cache->space_info->disk_used -= num_bytes * factor;
4835 spin_unlock(&cache->lock);
4836 spin_unlock(&cache->space_info->lock);
4838 set_extent_dirty(info->pinned_extents,
4839 bytenr, bytenr + num_bytes - 1,
4840 GFP_NOFS | __GFP_NOFAIL);
4842 btrfs_put_block_group(cache);
4844 bytenr += num_bytes;
4849 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4851 struct btrfs_block_group_cache *cache;
4854 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4858 bytenr = cache->key.objectid;
4859 btrfs_put_block_group(cache);
4864 static int pin_down_extent(struct btrfs_root *root,
4865 struct btrfs_block_group_cache *cache,
4866 u64 bytenr, u64 num_bytes, int reserved)
4868 spin_lock(&cache->space_info->lock);
4869 spin_lock(&cache->lock);
4870 cache->pinned += num_bytes;
4871 cache->space_info->bytes_pinned += num_bytes;
4873 cache->reserved -= num_bytes;
4874 cache->space_info->bytes_reserved -= num_bytes;
4876 spin_unlock(&cache->lock);
4877 spin_unlock(&cache->space_info->lock);
4879 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4880 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4885 * this function must be called within transaction
4887 int btrfs_pin_extent(struct btrfs_root *root,
4888 u64 bytenr, u64 num_bytes, int reserved)
4890 struct btrfs_block_group_cache *cache;
4892 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4893 BUG_ON(!cache); /* Logic error */
4895 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4897 btrfs_put_block_group(cache);
4902 * this function must be called within transaction
4904 int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans,
4905 struct btrfs_root *root,
4906 u64 bytenr, u64 num_bytes)
4908 struct btrfs_block_group_cache *cache;
4910 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4911 BUG_ON(!cache); /* Logic error */
4914 * pull in the free space cache (if any) so that our pin
4915 * removes the free space from the cache. We have load_only set
4916 * to one because the slow code to read in the free extents does check
4917 * the pinned extents.
4919 cache_block_group(cache, trans, root, 1);
4921 pin_down_extent(root, cache, bytenr, num_bytes, 0);
4923 /* remove us from the free space cache (if we're there at all) */
4924 btrfs_remove_free_space(cache, bytenr, num_bytes);
4925 btrfs_put_block_group(cache);
4930 * btrfs_update_reserved_bytes - update the block_group and space info counters
4931 * @cache: The cache we are manipulating
4932 * @num_bytes: The number of bytes in question
4933 * @reserve: One of the reservation enums
4935 * This is called by the allocator when it reserves space, or by somebody who is
4936 * freeing space that was never actually used on disk. For example if you
4937 * reserve some space for a new leaf in transaction A and before transaction A
4938 * commits you free that leaf, you call this with reserve set to 0 in order to
4939 * clear the reservation.
4941 * Metadata reservations should be called with RESERVE_ALLOC so we do the proper
4942 * ENOSPC accounting. For data we handle the reservation through clearing the
4943 * delalloc bits in the io_tree. We have to do this since we could end up
4944 * allocating less disk space for the amount of data we have reserved in the
4945 * case of compression.
4947 * If this is a reservation and the block group has become read only we cannot
4948 * make the reservation and return -EAGAIN, otherwise this function always
4951 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
4952 u64 num_bytes, int reserve)
4954 struct btrfs_space_info *space_info = cache->space_info;
4957 spin_lock(&space_info->lock);
4958 spin_lock(&cache->lock);
4959 if (reserve != RESERVE_FREE) {
4963 cache->reserved += num_bytes;
4964 space_info->bytes_reserved += num_bytes;
4965 if (reserve == RESERVE_ALLOC) {
4966 trace_btrfs_space_reservation(cache->fs_info,
4967 "space_info", space_info->flags,
4969 space_info->bytes_may_use -= num_bytes;
4974 space_info->bytes_readonly += num_bytes;
4975 cache->reserved -= num_bytes;
4976 space_info->bytes_reserved -= num_bytes;
4977 space_info->reservation_progress++;
4979 spin_unlock(&cache->lock);
4980 spin_unlock(&space_info->lock);
4984 void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4985 struct btrfs_root *root)
4987 struct btrfs_fs_info *fs_info = root->fs_info;
4988 struct btrfs_caching_control *next;
4989 struct btrfs_caching_control *caching_ctl;
4990 struct btrfs_block_group_cache *cache;
4992 down_write(&fs_info->extent_commit_sem);
4994 list_for_each_entry_safe(caching_ctl, next,
4995 &fs_info->caching_block_groups, list) {
4996 cache = caching_ctl->block_group;
4997 if (block_group_cache_done(cache)) {
4998 cache->last_byte_to_unpin = (u64)-1;
4999 list_del_init(&caching_ctl->list);
5000 put_caching_control(caching_ctl);
5002 cache->last_byte_to_unpin = caching_ctl->progress;
5006 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
5007 fs_info->pinned_extents = &fs_info->freed_extents[1];
5009 fs_info->pinned_extents = &fs_info->freed_extents[0];
5011 up_write(&fs_info->extent_commit_sem);
5013 update_global_block_rsv(fs_info);
5016 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
5018 struct btrfs_fs_info *fs_info = root->fs_info;
5019 struct btrfs_block_group_cache *cache = NULL;
5020 struct btrfs_space_info *space_info;
5021 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5025 while (start <= end) {
5028 start >= cache->key.objectid + cache->key.offset) {
5030 btrfs_put_block_group(cache);
5031 cache = btrfs_lookup_block_group(fs_info, start);
5032 BUG_ON(!cache); /* Logic error */
5035 len = cache->key.objectid + cache->key.offset - start;
5036 len = min(len, end + 1 - start);
5038 if (start < cache->last_byte_to_unpin) {
5039 len = min(len, cache->last_byte_to_unpin - start);
5040 btrfs_add_free_space(cache, start, len);
5044 space_info = cache->space_info;
5046 spin_lock(&space_info->lock);
5047 spin_lock(&cache->lock);
5048 cache->pinned -= len;
5049 space_info->bytes_pinned -= len;
5051 space_info->bytes_readonly += len;
5054 spin_unlock(&cache->lock);
5055 if (!readonly && global_rsv->space_info == space_info) {
5056 spin_lock(&global_rsv->lock);
5057 if (!global_rsv->full) {
5058 len = min(len, global_rsv->size -
5059 global_rsv->reserved);
5060 global_rsv->reserved += len;
5061 space_info->bytes_may_use += len;
5062 if (global_rsv->reserved >= global_rsv->size)
5063 global_rsv->full = 1;
5065 spin_unlock(&global_rsv->lock);
5067 spin_unlock(&space_info->lock);
5071 btrfs_put_block_group(cache);
5075 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
5076 struct btrfs_root *root)
5078 struct btrfs_fs_info *fs_info = root->fs_info;
5079 struct extent_io_tree *unpin;
5087 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
5088 unpin = &fs_info->freed_extents[1];
5090 unpin = &fs_info->freed_extents[0];
5093 ret = find_first_extent_bit(unpin, 0, &start, &end,
5094 EXTENT_DIRTY, NULL);
5098 if (btrfs_test_opt(root, DISCARD))
5099 ret = btrfs_discard_extent(root, start,
5100 end + 1 - start, NULL);
5102 clear_extent_dirty(unpin, start, end, GFP_NOFS);
5103 unpin_extent_range(root, start, end);
5110 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
5111 struct btrfs_root *root,
5112 u64 bytenr, u64 num_bytes, u64 parent,
5113 u64 root_objectid, u64 owner_objectid,
5114 u64 owner_offset, int refs_to_drop,
5115 struct btrfs_delayed_extent_op *extent_op)
5117 struct btrfs_key key;
5118 struct btrfs_path *path;
5119 struct btrfs_fs_info *info = root->fs_info;
5120 struct btrfs_root *extent_root = info->extent_root;
5121 struct extent_buffer *leaf;
5122 struct btrfs_extent_item *ei;
5123 struct btrfs_extent_inline_ref *iref;
5126 int extent_slot = 0;
5127 int found_extent = 0;
5132 path = btrfs_alloc_path();
5137 path->leave_spinning = 1;
5139 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
5140 BUG_ON(!is_data && refs_to_drop != 1);
5142 ret = lookup_extent_backref(trans, extent_root, path, &iref,
5143 bytenr, num_bytes, parent,
5144 root_objectid, owner_objectid,
5147 extent_slot = path->slots[0];
5148 while (extent_slot >= 0) {
5149 btrfs_item_key_to_cpu(path->nodes[0], &key,
5151 if (key.objectid != bytenr)
5153 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
5154 key.offset == num_bytes) {
5158 if (path->slots[0] - extent_slot > 5)
5162 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
5163 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
5164 if (found_extent && item_size < sizeof(*ei))
5167 if (!found_extent) {
5169 ret = remove_extent_backref(trans, extent_root, path,
5173 btrfs_abort_transaction(trans, extent_root, ret);
5176 btrfs_release_path(path);
5177 path->leave_spinning = 1;
5179 key.objectid = bytenr;
5180 key.type = BTRFS_EXTENT_ITEM_KEY;
5181 key.offset = num_bytes;
5183 ret = btrfs_search_slot(trans, extent_root,
5186 printk(KERN_ERR "umm, got %d back from search"
5187 ", was looking for %llu\n", ret,
5188 (unsigned long long)bytenr);
5190 btrfs_print_leaf(extent_root,
5194 btrfs_abort_transaction(trans, extent_root, ret);
5197 extent_slot = path->slots[0];
5199 } else if (ret == -ENOENT) {
5200 btrfs_print_leaf(extent_root, path->nodes[0]);
5202 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
5203 "parent %llu root %llu owner %llu offset %llu\n",
5204 (unsigned long long)bytenr,
5205 (unsigned long long)parent,
5206 (unsigned long long)root_objectid,
5207 (unsigned long long)owner_objectid,
5208 (unsigned long long)owner_offset);
5210 btrfs_abort_transaction(trans, extent_root, ret);
5214 leaf = path->nodes[0];
5215 item_size = btrfs_item_size_nr(leaf, extent_slot);
5216 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
5217 if (item_size < sizeof(*ei)) {
5218 BUG_ON(found_extent || extent_slot != path->slots[0]);
5219 ret = convert_extent_item_v0(trans, extent_root, path,
5222 btrfs_abort_transaction(trans, extent_root, ret);
5226 btrfs_release_path(path);
5227 path->leave_spinning = 1;
5229 key.objectid = bytenr;
5230 key.type = BTRFS_EXTENT_ITEM_KEY;
5231 key.offset = num_bytes;
5233 ret = btrfs_search_slot(trans, extent_root, &key, path,
5236 printk(KERN_ERR "umm, got %d back from search"
5237 ", was looking for %llu\n", ret,
5238 (unsigned long long)bytenr);
5239 btrfs_print_leaf(extent_root, path->nodes[0]);
5242 btrfs_abort_transaction(trans, extent_root, ret);
5246 extent_slot = path->slots[0];
5247 leaf = path->nodes[0];
5248 item_size = btrfs_item_size_nr(leaf, extent_slot);
5251 BUG_ON(item_size < sizeof(*ei));
5252 ei = btrfs_item_ptr(leaf, extent_slot,
5253 struct btrfs_extent_item);
5254 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
5255 struct btrfs_tree_block_info *bi;
5256 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
5257 bi = (struct btrfs_tree_block_info *)(ei + 1);
5258 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
5261 refs = btrfs_extent_refs(leaf, ei);
5262 BUG_ON(refs < refs_to_drop);
5263 refs -= refs_to_drop;
5267 __run_delayed_extent_op(extent_op, leaf, ei);
5269 * In the case of inline back ref, reference count will
5270 * be updated by remove_extent_backref
5273 BUG_ON(!found_extent);
5275 btrfs_set_extent_refs(leaf, ei, refs);
5276 btrfs_mark_buffer_dirty(leaf);
5279 ret = remove_extent_backref(trans, extent_root, path,
5283 btrfs_abort_transaction(trans, extent_root, ret);
5289 BUG_ON(is_data && refs_to_drop !=
5290 extent_data_ref_count(root, path, iref));
5292 BUG_ON(path->slots[0] != extent_slot);
5294 BUG_ON(path->slots[0] != extent_slot + 1);
5295 path->slots[0] = extent_slot;
5300 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
5303 btrfs_abort_transaction(trans, extent_root, ret);
5306 btrfs_release_path(path);
5309 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
5311 btrfs_abort_transaction(trans, extent_root, ret);
5316 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
5318 btrfs_abort_transaction(trans, extent_root, ret);
5323 btrfs_free_path(path);
5328 * when we free an block, it is possible (and likely) that we free the last
5329 * delayed ref for that extent as well. This searches the delayed ref tree for
5330 * a given extent, and if there are no other delayed refs to be processed, it
5331 * removes it from the tree.
5333 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
5334 struct btrfs_root *root, u64 bytenr)
5336 struct btrfs_delayed_ref_head *head;
5337 struct btrfs_delayed_ref_root *delayed_refs;
5338 struct btrfs_delayed_ref_node *ref;
5339 struct rb_node *node;
5342 delayed_refs = &trans->transaction->delayed_refs;
5343 spin_lock(&delayed_refs->lock);
5344 head = btrfs_find_delayed_ref_head(trans, bytenr);
5348 node = rb_prev(&head->node.rb_node);
5352 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
5354 /* there are still entries for this ref, we can't drop it */
5355 if (ref->bytenr == bytenr)
5358 if (head->extent_op) {
5359 if (!head->must_insert_reserved)
5361 btrfs_free_delayed_extent_op(head->extent_op);
5362 head->extent_op = NULL;
5366 * waiting for the lock here would deadlock. If someone else has it
5367 * locked they are already in the process of dropping it anyway
5369 if (!mutex_trylock(&head->mutex))
5373 * at this point we have a head with no other entries. Go
5374 * ahead and process it.
5376 head->node.in_tree = 0;
5377 rb_erase(&head->node.rb_node, &delayed_refs->root);
5379 delayed_refs->num_entries--;
5382 * we don't take a ref on the node because we're removing it from the
5383 * tree, so we just steal the ref the tree was holding.
5385 delayed_refs->num_heads--;
5386 if (list_empty(&head->cluster))
5387 delayed_refs->num_heads_ready--;
5389 list_del_init(&head->cluster);
5390 spin_unlock(&delayed_refs->lock);
5392 BUG_ON(head->extent_op);
5393 if (head->must_insert_reserved)
5396 mutex_unlock(&head->mutex);
5397 btrfs_put_delayed_ref(&head->node);
5400 spin_unlock(&delayed_refs->lock);
5404 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
5405 struct btrfs_root *root,
5406 struct extent_buffer *buf,
5407 u64 parent, int last_ref)
5409 struct btrfs_block_group_cache *cache = NULL;
5412 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
5413 ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
5414 buf->start, buf->len,
5415 parent, root->root_key.objectid,
5416 btrfs_header_level(buf),
5417 BTRFS_DROP_DELAYED_REF, NULL, 0);
5418 BUG_ON(ret); /* -ENOMEM */
5424 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
5426 if (btrfs_header_generation(buf) == trans->transid) {
5427 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
5428 ret = check_ref_cleanup(trans, root, buf->start);
5433 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
5434 pin_down_extent(root, cache, buf->start, buf->len, 1);
5438 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
5440 btrfs_add_free_space(cache, buf->start, buf->len);
5441 btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE);
5445 * Deleting the buffer, clear the corrupt flag since it doesn't matter
5448 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
5449 btrfs_put_block_group(cache);
5452 /* Can return -ENOMEM */
5453 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root,
5454 u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
5455 u64 owner, u64 offset, int for_cow)
5458 struct btrfs_fs_info *fs_info = root->fs_info;
5461 * tree log blocks never actually go into the extent allocation
5462 * tree, just update pinning info and exit early.
5464 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
5465 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
5466 /* unlocks the pinned mutex */
5467 btrfs_pin_extent(root, bytenr, num_bytes, 1);
5469 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
5470 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
5472 parent, root_objectid, (int)owner,
5473 BTRFS_DROP_DELAYED_REF, NULL, for_cow);
5475 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
5477 parent, root_objectid, owner,
5478 offset, BTRFS_DROP_DELAYED_REF,
5484 static u64 stripe_align(struct btrfs_root *root, u64 val)
5486 u64 mask = ((u64)root->stripesize - 1);
5487 u64 ret = (val + mask) & ~mask;
5492 * when we wait for progress in the block group caching, its because
5493 * our allocation attempt failed at least once. So, we must sleep
5494 * and let some progress happen before we try again.
5496 * This function will sleep at least once waiting for new free space to
5497 * show up, and then it will check the block group free space numbers
5498 * for our min num_bytes. Another option is to have it go ahead
5499 * and look in the rbtree for a free extent of a given size, but this
5503 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
5506 struct btrfs_caching_control *caching_ctl;
5509 caching_ctl = get_caching_control(cache);
5513 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
5514 (cache->free_space_ctl->free_space >= num_bytes));
5516 put_caching_control(caching_ctl);
5521 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
5523 struct btrfs_caching_control *caching_ctl;
5526 caching_ctl = get_caching_control(cache);
5530 wait_event(caching_ctl->wait, block_group_cache_done(cache));
5532 put_caching_control(caching_ctl);
5536 int __get_raid_index(u64 flags)
5540 if (flags & BTRFS_BLOCK_GROUP_RAID10)
5542 else if (flags & BTRFS_BLOCK_GROUP_RAID1)
5544 else if (flags & BTRFS_BLOCK_GROUP_DUP)
5546 else if (flags & BTRFS_BLOCK_GROUP_RAID0)
5554 static int get_block_group_index(struct btrfs_block_group_cache *cache)
5556 return __get_raid_index(cache->flags);
5559 enum btrfs_loop_type {
5560 LOOP_CACHING_NOWAIT = 0,
5561 LOOP_CACHING_WAIT = 1,
5562 LOOP_ALLOC_CHUNK = 2,
5563 LOOP_NO_EMPTY_SIZE = 3,
5567 * walks the btree of allocated extents and find a hole of a given size.
5568 * The key ins is changed to record the hole:
5569 * ins->objectid == block start
5570 * ins->flags = BTRFS_EXTENT_ITEM_KEY
5571 * ins->offset == number of blocks
5572 * Any available blocks before search_start are skipped.
5574 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
5575 struct btrfs_root *orig_root,
5576 u64 num_bytes, u64 empty_size,
5577 u64 hint_byte, struct btrfs_key *ins,
5581 struct btrfs_root *root = orig_root->fs_info->extent_root;
5582 struct btrfs_free_cluster *last_ptr = NULL;
5583 struct btrfs_block_group_cache *block_group = NULL;
5584 struct btrfs_block_group_cache *used_block_group;
5585 u64 search_start = 0;
5586 int empty_cluster = 2 * 1024 * 1024;
5587 struct btrfs_space_info *space_info;
5589 int index = __get_raid_index(data);
5590 int alloc_type = (data & BTRFS_BLOCK_GROUP_DATA) ?
5591 RESERVE_ALLOC_NO_ACCOUNT : RESERVE_ALLOC;
5592 bool found_uncached_bg = false;
5593 bool failed_cluster_refill = false;
5594 bool failed_alloc = false;
5595 bool use_cluster = true;
5596 bool have_caching_bg = false;
5598 WARN_ON(num_bytes < root->sectorsize);
5599 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
5603 trace_find_free_extent(orig_root, num_bytes, empty_size, data);
5605 space_info = __find_space_info(root->fs_info, data);
5607 printk(KERN_ERR "No space info for %llu\n", data);
5612 * If the space info is for both data and metadata it means we have a
5613 * small filesystem and we can't use the clustering stuff.
5615 if (btrfs_mixed_space_info(space_info))
5616 use_cluster = false;
5618 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
5619 last_ptr = &root->fs_info->meta_alloc_cluster;
5620 if (!btrfs_test_opt(root, SSD))
5621 empty_cluster = 64 * 1024;
5624 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
5625 btrfs_test_opt(root, SSD)) {
5626 last_ptr = &root->fs_info->data_alloc_cluster;
5630 spin_lock(&last_ptr->lock);
5631 if (last_ptr->block_group)
5632 hint_byte = last_ptr->window_start;
5633 spin_unlock(&last_ptr->lock);
5636 search_start = max(search_start, first_logical_byte(root, 0));
5637 search_start = max(search_start, hint_byte);
5642 if (search_start == hint_byte) {
5643 block_group = btrfs_lookup_block_group(root->fs_info,
5645 used_block_group = block_group;
5647 * we don't want to use the block group if it doesn't match our
5648 * allocation bits, or if its not cached.
5650 * However if we are re-searching with an ideal block group
5651 * picked out then we don't care that the block group is cached.
5653 if (block_group && block_group_bits(block_group, data) &&
5654 block_group->cached != BTRFS_CACHE_NO) {
5655 down_read(&space_info->groups_sem);
5656 if (list_empty(&block_group->list) ||
5659 * someone is removing this block group,
5660 * we can't jump into the have_block_group
5661 * target because our list pointers are not
5664 btrfs_put_block_group(block_group);
5665 up_read(&space_info->groups_sem);
5667 index = get_block_group_index(block_group);
5668 goto have_block_group;
5670 } else if (block_group) {
5671 btrfs_put_block_group(block_group);
5675 have_caching_bg = false;
5676 down_read(&space_info->groups_sem);
5677 list_for_each_entry(block_group, &space_info->block_groups[index],
5682 used_block_group = block_group;
5683 btrfs_get_block_group(block_group);
5684 search_start = block_group->key.objectid;
5687 * this can happen if we end up cycling through all the
5688 * raid types, but we want to make sure we only allocate
5689 * for the proper type.
5691 if (!block_group_bits(block_group, data)) {
5692 u64 extra = BTRFS_BLOCK_GROUP_DUP |
5693 BTRFS_BLOCK_GROUP_RAID1 |
5694 BTRFS_BLOCK_GROUP_RAID10;
5697 * if they asked for extra copies and this block group
5698 * doesn't provide them, bail. This does allow us to
5699 * fill raid0 from raid1.
5701 if ((data & extra) && !(block_group->flags & extra))
5706 cached = block_group_cache_done(block_group);
5707 if (unlikely(!cached)) {
5708 found_uncached_bg = true;
5709 ret = cache_block_group(block_group, trans,
5715 if (unlikely(block_group->ro))
5719 * Ok we want to try and use the cluster allocator, so
5724 * the refill lock keeps out other
5725 * people trying to start a new cluster
5727 spin_lock(&last_ptr->refill_lock);
5728 used_block_group = last_ptr->block_group;
5729 if (used_block_group != block_group &&
5730 (!used_block_group ||
5731 used_block_group->ro ||
5732 !block_group_bits(used_block_group, data))) {
5733 used_block_group = block_group;
5734 goto refill_cluster;
5737 if (used_block_group != block_group)
5738 btrfs_get_block_group(used_block_group);
5740 offset = btrfs_alloc_from_cluster(used_block_group,
5741 last_ptr, num_bytes, used_block_group->key.objectid);
5743 /* we have a block, we're done */
5744 spin_unlock(&last_ptr->refill_lock);
5745 trace_btrfs_reserve_extent_cluster(root,
5746 block_group, search_start, num_bytes);
5750 WARN_ON(last_ptr->block_group != used_block_group);
5751 if (used_block_group != block_group) {
5752 btrfs_put_block_group(used_block_group);
5753 used_block_group = block_group;
5756 BUG_ON(used_block_group != block_group);
5757 /* If we are on LOOP_NO_EMPTY_SIZE, we can't
5758 * set up a new clusters, so lets just skip it
5759 * and let the allocator find whatever block
5760 * it can find. If we reach this point, we
5761 * will have tried the cluster allocator
5762 * plenty of times and not have found
5763 * anything, so we are likely way too
5764 * fragmented for the clustering stuff to find
5767 * However, if the cluster is taken from the
5768 * current block group, release the cluster
5769 * first, so that we stand a better chance of
5770 * succeeding in the unclustered
5772 if (loop >= LOOP_NO_EMPTY_SIZE &&
5773 last_ptr->block_group != block_group) {
5774 spin_unlock(&last_ptr->refill_lock);
5775 goto unclustered_alloc;
5779 * this cluster didn't work out, free it and
5782 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5784 if (loop >= LOOP_NO_EMPTY_SIZE) {
5785 spin_unlock(&last_ptr->refill_lock);
5786 goto unclustered_alloc;
5789 /* allocate a cluster in this block group */
5790 ret = btrfs_find_space_cluster(trans, root,
5791 block_group, last_ptr,
5792 search_start, num_bytes,
5793 empty_cluster + empty_size);
5796 * now pull our allocation out of this
5799 offset = btrfs_alloc_from_cluster(block_group,
5800 last_ptr, num_bytes,
5803 /* we found one, proceed */
5804 spin_unlock(&last_ptr->refill_lock);
5805 trace_btrfs_reserve_extent_cluster(root,
5806 block_group, search_start,
5810 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5811 && !failed_cluster_refill) {
5812 spin_unlock(&last_ptr->refill_lock);
5814 failed_cluster_refill = true;
5815 wait_block_group_cache_progress(block_group,
5816 num_bytes + empty_cluster + empty_size);
5817 goto have_block_group;
5821 * at this point we either didn't find a cluster
5822 * or we weren't able to allocate a block from our
5823 * cluster. Free the cluster we've been trying
5824 * to use, and go to the next block group
5826 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5827 spin_unlock(&last_ptr->refill_lock);
5832 spin_lock(&block_group->free_space_ctl->tree_lock);
5834 block_group->free_space_ctl->free_space <
5835 num_bytes + empty_cluster + empty_size) {
5836 spin_unlock(&block_group->free_space_ctl->tree_lock);
5839 spin_unlock(&block_group->free_space_ctl->tree_lock);
5841 offset = btrfs_find_space_for_alloc(block_group, search_start,
5842 num_bytes, empty_size);
5844 * If we didn't find a chunk, and we haven't failed on this
5845 * block group before, and this block group is in the middle of
5846 * caching and we are ok with waiting, then go ahead and wait
5847 * for progress to be made, and set failed_alloc to true.
5849 * If failed_alloc is true then we've already waited on this
5850 * block group once and should move on to the next block group.
5852 if (!offset && !failed_alloc && !cached &&
5853 loop > LOOP_CACHING_NOWAIT) {
5854 wait_block_group_cache_progress(block_group,
5855 num_bytes + empty_size);
5856 failed_alloc = true;
5857 goto have_block_group;
5858 } else if (!offset) {
5860 have_caching_bg = true;
5864 search_start = stripe_align(root, offset);
5866 /* move on to the next group */
5867 if (search_start + num_bytes >
5868 used_block_group->key.objectid + used_block_group->key.offset) {
5869 btrfs_add_free_space(used_block_group, offset, num_bytes);
5873 if (offset < search_start)
5874 btrfs_add_free_space(used_block_group, offset,
5875 search_start - offset);
5876 BUG_ON(offset > search_start);
5878 ret = btrfs_update_reserved_bytes(used_block_group, num_bytes,
5880 if (ret == -EAGAIN) {
5881 btrfs_add_free_space(used_block_group, offset, num_bytes);
5885 /* we are all good, lets return */
5886 ins->objectid = search_start;
5887 ins->offset = num_bytes;
5889 trace_btrfs_reserve_extent(orig_root, block_group,
5890 search_start, num_bytes);
5891 if (used_block_group != block_group)
5892 btrfs_put_block_group(used_block_group);
5893 btrfs_put_block_group(block_group);
5896 failed_cluster_refill = false;
5897 failed_alloc = false;
5898 BUG_ON(index != get_block_group_index(block_group));
5899 if (used_block_group != block_group)
5900 btrfs_put_block_group(used_block_group);
5901 btrfs_put_block_group(block_group);
5903 up_read(&space_info->groups_sem);
5905 if (!ins->objectid && loop >= LOOP_CACHING_WAIT && have_caching_bg)
5908 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5912 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5913 * caching kthreads as we move along
5914 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5915 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5916 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5919 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE) {
5922 if (loop == LOOP_ALLOC_CHUNK) {
5923 ret = do_chunk_alloc(trans, root, data,
5926 * Do not bail out on ENOSPC since we
5927 * can do more things.
5929 if (ret < 0 && ret != -ENOSPC) {
5930 btrfs_abort_transaction(trans,
5936 if (loop == LOOP_NO_EMPTY_SIZE) {
5942 } else if (!ins->objectid) {
5944 } else if (ins->objectid) {
5952 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5953 int dump_block_groups)
5955 struct btrfs_block_group_cache *cache;
5958 spin_lock(&info->lock);
5959 printk(KERN_INFO "space_info %llu has %llu free, is %sfull\n",
5960 (unsigned long long)info->flags,
5961 (unsigned long long)(info->total_bytes - info->bytes_used -
5962 info->bytes_pinned - info->bytes_reserved -
5963 info->bytes_readonly),
5964 (info->full) ? "" : "not ");
5965 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5966 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5967 (unsigned long long)info->total_bytes,
5968 (unsigned long long)info->bytes_used,
5969 (unsigned long long)info->bytes_pinned,
5970 (unsigned long long)info->bytes_reserved,
5971 (unsigned long long)info->bytes_may_use,
5972 (unsigned long long)info->bytes_readonly);
5973 spin_unlock(&info->lock);
5975 if (!dump_block_groups)
5978 down_read(&info->groups_sem);
5980 list_for_each_entry(cache, &info->block_groups[index], list) {
5981 spin_lock(&cache->lock);
5982 printk(KERN_INFO "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s\n",
5983 (unsigned long long)cache->key.objectid,
5984 (unsigned long long)cache->key.offset,
5985 (unsigned long long)btrfs_block_group_used(&cache->item),
5986 (unsigned long long)cache->pinned,
5987 (unsigned long long)cache->reserved,
5988 cache->ro ? "[readonly]" : "");
5989 btrfs_dump_free_space(cache, bytes);
5990 spin_unlock(&cache->lock);
5992 if (++index < BTRFS_NR_RAID_TYPES)
5994 up_read(&info->groups_sem);
5997 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5998 struct btrfs_root *root,
5999 u64 num_bytes, u64 min_alloc_size,
6000 u64 empty_size, u64 hint_byte,
6001 struct btrfs_key *ins, u64 data)
6003 bool final_tried = false;
6006 data = btrfs_get_alloc_profile(root, data);
6008 WARN_ON(num_bytes < root->sectorsize);
6009 ret = find_free_extent(trans, root, num_bytes, empty_size,
6010 hint_byte, ins, data);
6012 if (ret == -ENOSPC) {
6014 num_bytes = num_bytes >> 1;
6015 num_bytes = num_bytes & ~(root->sectorsize - 1);
6016 num_bytes = max(num_bytes, min_alloc_size);
6017 if (num_bytes == min_alloc_size)
6020 } else if (btrfs_test_opt(root, ENOSPC_DEBUG)) {
6021 struct btrfs_space_info *sinfo;
6023 sinfo = __find_space_info(root->fs_info, data);
6024 printk(KERN_ERR "btrfs allocation failed flags %llu, "
6025 "wanted %llu\n", (unsigned long long)data,
6026 (unsigned long long)num_bytes);
6028 dump_space_info(sinfo, num_bytes, 1);
6032 trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
6037 static int __btrfs_free_reserved_extent(struct btrfs_root *root,
6038 u64 start, u64 len, int pin)
6040 struct btrfs_block_group_cache *cache;
6043 cache = btrfs_lookup_block_group(root->fs_info, start);
6045 printk(KERN_ERR "Unable to find block group for %llu\n",
6046 (unsigned long long)start);
6050 if (btrfs_test_opt(root, DISCARD))
6051 ret = btrfs_discard_extent(root, start, len, NULL);
6054 pin_down_extent(root, cache, start, len, 1);
6056 btrfs_add_free_space(cache, start, len);
6057 btrfs_update_reserved_bytes(cache, len, RESERVE_FREE);
6059 btrfs_put_block_group(cache);
6061 trace_btrfs_reserved_extent_free(root, start, len);
6066 int btrfs_free_reserved_extent(struct btrfs_root *root,
6069 return __btrfs_free_reserved_extent(root, start, len, 0);
6072 int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
6075 return __btrfs_free_reserved_extent(root, start, len, 1);
6078 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
6079 struct btrfs_root *root,
6080 u64 parent, u64 root_objectid,
6081 u64 flags, u64 owner, u64 offset,
6082 struct btrfs_key *ins, int ref_mod)
6085 struct btrfs_fs_info *fs_info = root->fs_info;
6086 struct btrfs_extent_item *extent_item;
6087 struct btrfs_extent_inline_ref *iref;
6088 struct btrfs_path *path;
6089 struct extent_buffer *leaf;
6094 type = BTRFS_SHARED_DATA_REF_KEY;
6096 type = BTRFS_EXTENT_DATA_REF_KEY;
6098 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
6100 path = btrfs_alloc_path();
6104 path->leave_spinning = 1;
6105 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
6108 btrfs_free_path(path);
6112 leaf = path->nodes[0];
6113 extent_item = btrfs_item_ptr(leaf, path->slots[0],
6114 struct btrfs_extent_item);
6115 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
6116 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
6117 btrfs_set_extent_flags(leaf, extent_item,
6118 flags | BTRFS_EXTENT_FLAG_DATA);
6120 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
6121 btrfs_set_extent_inline_ref_type(leaf, iref, type);
6123 struct btrfs_shared_data_ref *ref;
6124 ref = (struct btrfs_shared_data_ref *)(iref + 1);
6125 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
6126 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
6128 struct btrfs_extent_data_ref *ref;
6129 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
6130 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
6131 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
6132 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
6133 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
6136 btrfs_mark_buffer_dirty(path->nodes[0]);
6137 btrfs_free_path(path);
6139 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
6140 if (ret) { /* -ENOENT, logic error */
6141 printk(KERN_ERR "btrfs update block group failed for %llu "
6142 "%llu\n", (unsigned long long)ins->objectid,
6143 (unsigned long long)ins->offset);
6149 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
6150 struct btrfs_root *root,
6151 u64 parent, u64 root_objectid,
6152 u64 flags, struct btrfs_disk_key *key,
6153 int level, struct btrfs_key *ins)
6156 struct btrfs_fs_info *fs_info = root->fs_info;
6157 struct btrfs_extent_item *extent_item;
6158 struct btrfs_tree_block_info *block_info;
6159 struct btrfs_extent_inline_ref *iref;
6160 struct btrfs_path *path;
6161 struct extent_buffer *leaf;
6162 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
6164 path = btrfs_alloc_path();
6168 path->leave_spinning = 1;
6169 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
6172 btrfs_free_path(path);
6176 leaf = path->nodes[0];
6177 extent_item = btrfs_item_ptr(leaf, path->slots[0],
6178 struct btrfs_extent_item);
6179 btrfs_set_extent_refs(leaf, extent_item, 1);
6180 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
6181 btrfs_set_extent_flags(leaf, extent_item,
6182 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
6183 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
6185 btrfs_set_tree_block_key(leaf, block_info, key);
6186 btrfs_set_tree_block_level(leaf, block_info, level);
6188 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
6190 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
6191 btrfs_set_extent_inline_ref_type(leaf, iref,
6192 BTRFS_SHARED_BLOCK_REF_KEY);
6193 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
6195 btrfs_set_extent_inline_ref_type(leaf, iref,
6196 BTRFS_TREE_BLOCK_REF_KEY);
6197 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
6200 btrfs_mark_buffer_dirty(leaf);
6201 btrfs_free_path(path);
6203 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
6204 if (ret) { /* -ENOENT, logic error */
6205 printk(KERN_ERR "btrfs update block group failed for %llu "
6206 "%llu\n", (unsigned long long)ins->objectid,
6207 (unsigned long long)ins->offset);
6213 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
6214 struct btrfs_root *root,
6215 u64 root_objectid, u64 owner,
6216 u64 offset, struct btrfs_key *ins)
6220 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
6222 ret = btrfs_add_delayed_data_ref(root->fs_info, trans, ins->objectid,
6224 root_objectid, owner, offset,
6225 BTRFS_ADD_DELAYED_EXTENT, NULL, 0);
6230 * this is used by the tree logging recovery code. It records that
6231 * an extent has been allocated and makes sure to clear the free
6232 * space cache bits as well
6234 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
6235 struct btrfs_root *root,
6236 u64 root_objectid, u64 owner, u64 offset,
6237 struct btrfs_key *ins)
6240 struct btrfs_block_group_cache *block_group;
6241 struct btrfs_caching_control *caching_ctl;
6242 u64 start = ins->objectid;
6243 u64 num_bytes = ins->offset;
6245 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
6246 cache_block_group(block_group, trans, NULL, 0);
6247 caching_ctl = get_caching_control(block_group);
6250 BUG_ON(!block_group_cache_done(block_group));
6251 ret = btrfs_remove_free_space(block_group, start, num_bytes);
6252 BUG_ON(ret); /* -ENOMEM */
6254 mutex_lock(&caching_ctl->mutex);
6256 if (start >= caching_ctl->progress) {
6257 ret = add_excluded_extent(root, start, num_bytes);
6258 BUG_ON(ret); /* -ENOMEM */
6259 } else if (start + num_bytes <= caching_ctl->progress) {
6260 ret = btrfs_remove_free_space(block_group,
6262 BUG_ON(ret); /* -ENOMEM */
6264 num_bytes = caching_ctl->progress - start;
6265 ret = btrfs_remove_free_space(block_group,
6267 BUG_ON(ret); /* -ENOMEM */
6269 start = caching_ctl->progress;
6270 num_bytes = ins->objectid + ins->offset -
6271 caching_ctl->progress;
6272 ret = add_excluded_extent(root, start, num_bytes);
6273 BUG_ON(ret); /* -ENOMEM */
6276 mutex_unlock(&caching_ctl->mutex);
6277 put_caching_control(caching_ctl);
6280 ret = btrfs_update_reserved_bytes(block_group, ins->offset,
6281 RESERVE_ALLOC_NO_ACCOUNT);
6282 BUG_ON(ret); /* logic error */
6283 btrfs_put_block_group(block_group);
6284 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
6285 0, owner, offset, ins, 1);
6289 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
6290 struct btrfs_root *root,
6291 u64 bytenr, u32 blocksize,
6294 struct extent_buffer *buf;
6296 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
6298 return ERR_PTR(-ENOMEM);
6299 btrfs_set_header_generation(buf, trans->transid);
6300 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
6301 btrfs_tree_lock(buf);
6302 clean_tree_block(trans, root, buf);
6303 clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
6305 btrfs_set_lock_blocking(buf);
6306 btrfs_set_buffer_uptodate(buf);
6308 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
6310 * we allow two log transactions at a time, use different
6311 * EXENT bit to differentiate dirty pages.
6313 if (root->log_transid % 2 == 0)
6314 set_extent_dirty(&root->dirty_log_pages, buf->start,
6315 buf->start + buf->len - 1, GFP_NOFS);
6317 set_extent_new(&root->dirty_log_pages, buf->start,
6318 buf->start + buf->len - 1, GFP_NOFS);
6320 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
6321 buf->start + buf->len - 1, GFP_NOFS);
6323 trans->blocks_used++;
6324 /* this returns a buffer locked for blocking */
6328 static struct btrfs_block_rsv *
6329 use_block_rsv(struct btrfs_trans_handle *trans,
6330 struct btrfs_root *root, u32 blocksize)
6332 struct btrfs_block_rsv *block_rsv;
6333 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
6336 block_rsv = get_block_rsv(trans, root);
6338 if (block_rsv->size == 0) {
6339 ret = reserve_metadata_bytes(root, block_rsv, blocksize,
6340 BTRFS_RESERVE_NO_FLUSH);
6342 * If we couldn't reserve metadata bytes try and use some from
6343 * the global reserve.
6345 if (ret && block_rsv != global_rsv) {
6346 ret = block_rsv_use_bytes(global_rsv, blocksize);
6349 return ERR_PTR(ret);
6351 return ERR_PTR(ret);
6356 ret = block_rsv_use_bytes(block_rsv, blocksize);
6359 if (ret && !block_rsv->failfast) {
6360 static DEFINE_RATELIMIT_STATE(_rs,
6361 DEFAULT_RATELIMIT_INTERVAL,
6362 /*DEFAULT_RATELIMIT_BURST*/ 2);
6363 if (__ratelimit(&_rs))
6364 WARN(1, KERN_DEBUG "btrfs: block rsv returned %d\n",
6366 ret = reserve_metadata_bytes(root, block_rsv, blocksize,
6367 BTRFS_RESERVE_NO_FLUSH);
6370 } else if (ret && block_rsv != global_rsv) {
6371 ret = block_rsv_use_bytes(global_rsv, blocksize);
6377 return ERR_PTR(-ENOSPC);
6380 static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
6381 struct btrfs_block_rsv *block_rsv, u32 blocksize)
6383 block_rsv_add_bytes(block_rsv, blocksize, 0);
6384 block_rsv_release_bytes(fs_info, block_rsv, NULL, 0);
6388 * finds a free extent and does all the dirty work required for allocation
6389 * returns the key for the extent through ins, and a tree buffer for
6390 * the first block of the extent through buf.
6392 * returns the tree buffer or NULL.
6394 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
6395 struct btrfs_root *root, u32 blocksize,
6396 u64 parent, u64 root_objectid,
6397 struct btrfs_disk_key *key, int level,
6398 u64 hint, u64 empty_size)
6400 struct btrfs_key ins;
6401 struct btrfs_block_rsv *block_rsv;
6402 struct extent_buffer *buf;
6407 block_rsv = use_block_rsv(trans, root, blocksize);
6408 if (IS_ERR(block_rsv))
6409 return ERR_CAST(block_rsv);
6411 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
6412 empty_size, hint, &ins, 0);
6414 unuse_block_rsv(root->fs_info, block_rsv, blocksize);
6415 return ERR_PTR(ret);
6418 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
6420 BUG_ON(IS_ERR(buf)); /* -ENOMEM */
6422 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
6424 parent = ins.objectid;
6425 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
6429 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
6430 struct btrfs_delayed_extent_op *extent_op;
6431 extent_op = btrfs_alloc_delayed_extent_op();
6432 BUG_ON(!extent_op); /* -ENOMEM */
6434 memcpy(&extent_op->key, key, sizeof(extent_op->key));
6436 memset(&extent_op->key, 0, sizeof(extent_op->key));
6437 extent_op->flags_to_set = flags;
6438 extent_op->update_key = 1;
6439 extent_op->update_flags = 1;
6440 extent_op->is_data = 0;
6442 ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
6444 ins.offset, parent, root_objectid,
6445 level, BTRFS_ADD_DELAYED_EXTENT,
6447 BUG_ON(ret); /* -ENOMEM */
6452 struct walk_control {
6453 u64 refs[BTRFS_MAX_LEVEL];
6454 u64 flags[BTRFS_MAX_LEVEL];
6455 struct btrfs_key update_progress;
6466 #define DROP_REFERENCE 1
6467 #define UPDATE_BACKREF 2
6469 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
6470 struct btrfs_root *root,
6471 struct walk_control *wc,
6472 struct btrfs_path *path)
6480 struct btrfs_key key;
6481 struct extent_buffer *eb;
6486 if (path->slots[wc->level] < wc->reada_slot) {
6487 wc->reada_count = wc->reada_count * 2 / 3;
6488 wc->reada_count = max(wc->reada_count, 2);
6490 wc->reada_count = wc->reada_count * 3 / 2;
6491 wc->reada_count = min_t(int, wc->reada_count,
6492 BTRFS_NODEPTRS_PER_BLOCK(root));
6495 eb = path->nodes[wc->level];
6496 nritems = btrfs_header_nritems(eb);
6497 blocksize = btrfs_level_size(root, wc->level - 1);
6499 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
6500 if (nread >= wc->reada_count)
6504 bytenr = btrfs_node_blockptr(eb, slot);
6505 generation = btrfs_node_ptr_generation(eb, slot);
6507 if (slot == path->slots[wc->level])
6510 if (wc->stage == UPDATE_BACKREF &&
6511 generation <= root->root_key.offset)
6514 /* We don't lock the tree block, it's OK to be racy here */
6515 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6517 /* We don't care about errors in readahead. */
6522 if (wc->stage == DROP_REFERENCE) {
6526 if (wc->level == 1 &&
6527 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6529 if (!wc->update_ref ||
6530 generation <= root->root_key.offset)
6532 btrfs_node_key_to_cpu(eb, &key, slot);
6533 ret = btrfs_comp_cpu_keys(&key,
6534 &wc->update_progress);
6538 if (wc->level == 1 &&
6539 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6543 ret = readahead_tree_block(root, bytenr, blocksize,
6549 wc->reada_slot = slot;
6553 * hepler to process tree block while walking down the tree.
6555 * when wc->stage == UPDATE_BACKREF, this function updates
6556 * back refs for pointers in the block.
6558 * NOTE: return value 1 means we should stop walking down.
6560 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
6561 struct btrfs_root *root,
6562 struct btrfs_path *path,
6563 struct walk_control *wc, int lookup_info)
6565 int level = wc->level;
6566 struct extent_buffer *eb = path->nodes[level];
6567 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6570 if (wc->stage == UPDATE_BACKREF &&
6571 btrfs_header_owner(eb) != root->root_key.objectid)
6575 * when reference count of tree block is 1, it won't increase
6576 * again. once full backref flag is set, we never clear it.
6579 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
6580 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
6581 BUG_ON(!path->locks[level]);
6582 ret = btrfs_lookup_extent_info(trans, root,
6586 BUG_ON(ret == -ENOMEM);
6589 BUG_ON(wc->refs[level] == 0);
6592 if (wc->stage == DROP_REFERENCE) {
6593 if (wc->refs[level] > 1)
6596 if (path->locks[level] && !wc->keep_locks) {
6597 btrfs_tree_unlock_rw(eb, path->locks[level]);
6598 path->locks[level] = 0;
6603 /* wc->stage == UPDATE_BACKREF */
6604 if (!(wc->flags[level] & flag)) {
6605 BUG_ON(!path->locks[level]);
6606 ret = btrfs_inc_ref(trans, root, eb, 1, wc->for_reloc);
6607 BUG_ON(ret); /* -ENOMEM */
6608 ret = btrfs_dec_ref(trans, root, eb, 0, wc->for_reloc);
6609 BUG_ON(ret); /* -ENOMEM */
6610 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
6612 BUG_ON(ret); /* -ENOMEM */
6613 wc->flags[level] |= flag;
6617 * the block is shared by multiple trees, so it's not good to
6618 * keep the tree lock
6620 if (path->locks[level] && level > 0) {
6621 btrfs_tree_unlock_rw(eb, path->locks[level]);
6622 path->locks[level] = 0;
6628 * hepler to process tree block pointer.
6630 * when wc->stage == DROP_REFERENCE, this function checks
6631 * reference count of the block pointed to. if the block
6632 * is shared and we need update back refs for the subtree
6633 * rooted at the block, this function changes wc->stage to
6634 * UPDATE_BACKREF. if the block is shared and there is no
6635 * need to update back, this function drops the reference
6638 * NOTE: return value 1 means we should stop walking down.
6640 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
6641 struct btrfs_root *root,
6642 struct btrfs_path *path,
6643 struct walk_control *wc, int *lookup_info)
6649 struct btrfs_key key;
6650 struct extent_buffer *next;
6651 int level = wc->level;
6655 generation = btrfs_node_ptr_generation(path->nodes[level],
6656 path->slots[level]);
6658 * if the lower level block was created before the snapshot
6659 * was created, we know there is no need to update back refs
6662 if (wc->stage == UPDATE_BACKREF &&
6663 generation <= root->root_key.offset) {
6668 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
6669 blocksize = btrfs_level_size(root, level - 1);
6671 next = btrfs_find_tree_block(root, bytenr, blocksize);
6673 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
6678 btrfs_tree_lock(next);
6679 btrfs_set_lock_blocking(next);
6681 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6682 &wc->refs[level - 1],
6683 &wc->flags[level - 1]);
6685 btrfs_tree_unlock(next);
6689 BUG_ON(wc->refs[level - 1] == 0);
6692 if (wc->stage == DROP_REFERENCE) {
6693 if (wc->refs[level - 1] > 1) {
6695 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6698 if (!wc->update_ref ||
6699 generation <= root->root_key.offset)
6702 btrfs_node_key_to_cpu(path->nodes[level], &key,
6703 path->slots[level]);
6704 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
6708 wc->stage = UPDATE_BACKREF;
6709 wc->shared_level = level - 1;
6713 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6717 if (!btrfs_buffer_uptodate(next, generation, 0)) {
6718 btrfs_tree_unlock(next);
6719 free_extent_buffer(next);
6725 if (reada && level == 1)
6726 reada_walk_down(trans, root, wc, path);
6727 next = read_tree_block(root, bytenr, blocksize, generation);
6730 btrfs_tree_lock(next);
6731 btrfs_set_lock_blocking(next);
6735 BUG_ON(level != btrfs_header_level(next));
6736 path->nodes[level] = next;
6737 path->slots[level] = 0;
6738 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6744 wc->refs[level - 1] = 0;
6745 wc->flags[level - 1] = 0;
6746 if (wc->stage == DROP_REFERENCE) {
6747 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6748 parent = path->nodes[level]->start;
6750 BUG_ON(root->root_key.objectid !=
6751 btrfs_header_owner(path->nodes[level]));
6755 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
6756 root->root_key.objectid, level - 1, 0, 0);
6757 BUG_ON(ret); /* -ENOMEM */
6759 btrfs_tree_unlock(next);
6760 free_extent_buffer(next);
6766 * hepler to process tree block while walking up the tree.
6768 * when wc->stage == DROP_REFERENCE, this function drops
6769 * reference count on the block.
6771 * when wc->stage == UPDATE_BACKREF, this function changes
6772 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6773 * to UPDATE_BACKREF previously while processing the block.
6775 * NOTE: return value 1 means we should stop walking up.
6777 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6778 struct btrfs_root *root,
6779 struct btrfs_path *path,
6780 struct walk_control *wc)
6783 int level = wc->level;
6784 struct extent_buffer *eb = path->nodes[level];
6787 if (wc->stage == UPDATE_BACKREF) {
6788 BUG_ON(wc->shared_level < level);
6789 if (level < wc->shared_level)
6792 ret = find_next_key(path, level + 1, &wc->update_progress);
6796 wc->stage = DROP_REFERENCE;
6797 wc->shared_level = -1;
6798 path->slots[level] = 0;
6801 * check reference count again if the block isn't locked.
6802 * we should start walking down the tree again if reference
6805 if (!path->locks[level]) {
6807 btrfs_tree_lock(eb);
6808 btrfs_set_lock_blocking(eb);
6809 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6811 ret = btrfs_lookup_extent_info(trans, root,
6816 btrfs_tree_unlock_rw(eb, path->locks[level]);
6817 path->locks[level] = 0;
6820 BUG_ON(wc->refs[level] == 0);
6821 if (wc->refs[level] == 1) {
6822 btrfs_tree_unlock_rw(eb, path->locks[level]);
6823 path->locks[level] = 0;
6829 /* wc->stage == DROP_REFERENCE */
6830 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6832 if (wc->refs[level] == 1) {
6834 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6835 ret = btrfs_dec_ref(trans, root, eb, 1,
6838 ret = btrfs_dec_ref(trans, root, eb, 0,
6840 BUG_ON(ret); /* -ENOMEM */
6842 /* make block locked assertion in clean_tree_block happy */
6843 if (!path->locks[level] &&
6844 btrfs_header_generation(eb) == trans->transid) {
6845 btrfs_tree_lock(eb);
6846 btrfs_set_lock_blocking(eb);
6847 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6849 clean_tree_block(trans, root, eb);
6852 if (eb == root->node) {
6853 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6856 BUG_ON(root->root_key.objectid !=
6857 btrfs_header_owner(eb));
6859 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6860 parent = path->nodes[level + 1]->start;
6862 BUG_ON(root->root_key.objectid !=
6863 btrfs_header_owner(path->nodes[level + 1]));
6866 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6868 wc->refs[level] = 0;
6869 wc->flags[level] = 0;
6873 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6874 struct btrfs_root *root,
6875 struct btrfs_path *path,
6876 struct walk_control *wc)
6878 int level = wc->level;
6879 int lookup_info = 1;
6882 while (level >= 0) {
6883 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6890 if (path->slots[level] >=
6891 btrfs_header_nritems(path->nodes[level]))
6894 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6896 path->slots[level]++;
6905 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6906 struct btrfs_root *root,
6907 struct btrfs_path *path,
6908 struct walk_control *wc, int max_level)
6910 int level = wc->level;
6913 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6914 while (level < max_level && path->nodes[level]) {
6916 if (path->slots[level] + 1 <
6917 btrfs_header_nritems(path->nodes[level])) {
6918 path->slots[level]++;
6921 ret = walk_up_proc(trans, root, path, wc);
6925 if (path->locks[level]) {
6926 btrfs_tree_unlock_rw(path->nodes[level],
6927 path->locks[level]);
6928 path->locks[level] = 0;
6930 free_extent_buffer(path->nodes[level]);
6931 path->nodes[level] = NULL;
6939 * drop a subvolume tree.
6941 * this function traverses the tree freeing any blocks that only
6942 * referenced by the tree.
6944 * when a shared tree block is found. this function decreases its
6945 * reference count by one. if update_ref is true, this function
6946 * also make sure backrefs for the shared block and all lower level
6947 * blocks are properly updated.
6949 int btrfs_drop_snapshot(struct btrfs_root *root,
6950 struct btrfs_block_rsv *block_rsv, int update_ref,
6953 struct btrfs_path *path;
6954 struct btrfs_trans_handle *trans;
6955 struct btrfs_root *tree_root = root->fs_info->tree_root;
6956 struct btrfs_root_item *root_item = &root->root_item;
6957 struct walk_control *wc;
6958 struct btrfs_key key;
6963 path = btrfs_alloc_path();
6969 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6971 btrfs_free_path(path);
6976 trans = btrfs_start_transaction(tree_root, 0);
6977 if (IS_ERR(trans)) {
6978 err = PTR_ERR(trans);
6983 trans->block_rsv = block_rsv;
6985 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6986 level = btrfs_header_level(root->node);
6987 path->nodes[level] = btrfs_lock_root_node(root);
6988 btrfs_set_lock_blocking(path->nodes[level]);
6989 path->slots[level] = 0;
6990 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6991 memset(&wc->update_progress, 0,
6992 sizeof(wc->update_progress));
6994 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6995 memcpy(&wc->update_progress, &key,
6996 sizeof(wc->update_progress));
6998 level = root_item->drop_level;
7000 path->lowest_level = level;
7001 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
7002 path->lowest_level = 0;
7010 * unlock our path, this is safe because only this
7011 * function is allowed to delete this snapshot
7013 btrfs_unlock_up_safe(path, 0);
7015 level = btrfs_header_level(root->node);
7017 btrfs_tree_lock(path->nodes[level]);
7018 btrfs_set_lock_blocking(path->nodes[level]);
7020 ret = btrfs_lookup_extent_info(trans, root,
7021 path->nodes[level]->start,
7022 path->nodes[level]->len,
7029 BUG_ON(wc->refs[level] == 0);
7031 if (level == root_item->drop_level)
7034 btrfs_tree_unlock(path->nodes[level]);
7035 WARN_ON(wc->refs[level] != 1);
7041 wc->shared_level = -1;
7042 wc->stage = DROP_REFERENCE;
7043 wc->update_ref = update_ref;
7045 wc->for_reloc = for_reloc;
7046 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
7049 ret = walk_down_tree(trans, root, path, wc);
7055 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
7062 BUG_ON(wc->stage != DROP_REFERENCE);
7066 if (wc->stage == DROP_REFERENCE) {
7068 btrfs_node_key(path->nodes[level],
7069 &root_item->drop_progress,
7070 path->slots[level]);
7071 root_item->drop_level = level;
7074 BUG_ON(wc->level == 0);
7075 if (btrfs_should_end_transaction(trans, tree_root)) {
7076 ret = btrfs_update_root(trans, tree_root,
7080 btrfs_abort_transaction(trans, tree_root, ret);
7085 btrfs_end_transaction_throttle(trans, tree_root);
7086 trans = btrfs_start_transaction(tree_root, 0);
7087 if (IS_ERR(trans)) {
7088 err = PTR_ERR(trans);
7092 trans->block_rsv = block_rsv;
7095 btrfs_release_path(path);
7099 ret = btrfs_del_root(trans, tree_root, &root->root_key);
7101 btrfs_abort_transaction(trans, tree_root, ret);
7105 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
7106 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
7109 btrfs_abort_transaction(trans, tree_root, ret);
7112 } else if (ret > 0) {
7113 /* if we fail to delete the orphan item this time
7114 * around, it'll get picked up the next time.
7116 * The most common failure here is just -ENOENT.
7118 btrfs_del_orphan_item(trans, tree_root,
7119 root->root_key.objectid);
7123 if (root->in_radix) {
7124 btrfs_free_fs_root(tree_root->fs_info, root);
7126 free_extent_buffer(root->node);
7127 free_extent_buffer(root->commit_root);
7131 btrfs_end_transaction_throttle(trans, tree_root);
7134 btrfs_free_path(path);
7137 btrfs_std_error(root->fs_info, err);
7142 * drop subtree rooted at tree block 'node'.
7144 * NOTE: this function will unlock and release tree block 'node'
7145 * only used by relocation code
7147 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
7148 struct btrfs_root *root,
7149 struct extent_buffer *node,
7150 struct extent_buffer *parent)
7152 struct btrfs_path *path;
7153 struct walk_control *wc;
7159 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
7161 path = btrfs_alloc_path();
7165 wc = kzalloc(sizeof(*wc), GFP_NOFS);
7167 btrfs_free_path(path);
7171 btrfs_assert_tree_locked(parent);
7172 parent_level = btrfs_header_level(parent);
7173 extent_buffer_get(parent);
7174 path->nodes[parent_level] = parent;
7175 path->slots[parent_level] = btrfs_header_nritems(parent);
7177 btrfs_assert_tree_locked(node);
7178 level = btrfs_header_level(node);
7179 path->nodes[level] = node;
7180 path->slots[level] = 0;
7181 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
7183 wc->refs[parent_level] = 1;
7184 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
7186 wc->shared_level = -1;
7187 wc->stage = DROP_REFERENCE;
7191 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
7194 wret = walk_down_tree(trans, root, path, wc);
7200 wret = walk_up_tree(trans, root, path, wc, parent_level);
7208 btrfs_free_path(path);
7212 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
7218 * if restripe for this chunk_type is on pick target profile and
7219 * return, otherwise do the usual balance
7221 stripped = get_restripe_target(root->fs_info, flags);
7223 return extended_to_chunk(stripped);
7226 * we add in the count of missing devices because we want
7227 * to make sure that any RAID levels on a degraded FS
7228 * continue to be honored.
7230 num_devices = root->fs_info->fs_devices->rw_devices +
7231 root->fs_info->fs_devices->missing_devices;
7233 stripped = BTRFS_BLOCK_GROUP_RAID0 |
7234 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
7236 if (num_devices == 1) {
7237 stripped |= BTRFS_BLOCK_GROUP_DUP;
7238 stripped = flags & ~stripped;
7240 /* turn raid0 into single device chunks */
7241 if (flags & BTRFS_BLOCK_GROUP_RAID0)
7244 /* turn mirroring into duplication */
7245 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
7246 BTRFS_BLOCK_GROUP_RAID10))
7247 return stripped | BTRFS_BLOCK_GROUP_DUP;
7249 /* they already had raid on here, just return */
7250 if (flags & stripped)
7253 stripped |= BTRFS_BLOCK_GROUP_DUP;
7254 stripped = flags & ~stripped;
7256 /* switch duplicated blocks with raid1 */
7257 if (flags & BTRFS_BLOCK_GROUP_DUP)
7258 return stripped | BTRFS_BLOCK_GROUP_RAID1;
7260 /* this is drive concat, leave it alone */
7266 static int set_block_group_ro(struct btrfs_block_group_cache *cache, int force)
7268 struct btrfs_space_info *sinfo = cache->space_info;
7270 u64 min_allocable_bytes;
7275 * We need some metadata space and system metadata space for
7276 * allocating chunks in some corner cases until we force to set
7277 * it to be readonly.
7280 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
7282 min_allocable_bytes = 1 * 1024 * 1024;
7284 min_allocable_bytes = 0;
7286 spin_lock(&sinfo->lock);
7287 spin_lock(&cache->lock);
7294 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7295 cache->bytes_super - btrfs_block_group_used(&cache->item);
7297 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
7298 sinfo->bytes_may_use + sinfo->bytes_readonly + num_bytes +
7299 min_allocable_bytes <= sinfo->total_bytes) {
7300 sinfo->bytes_readonly += num_bytes;
7305 spin_unlock(&cache->lock);
7306 spin_unlock(&sinfo->lock);
7310 int btrfs_set_block_group_ro(struct btrfs_root *root,
7311 struct btrfs_block_group_cache *cache)
7314 struct btrfs_trans_handle *trans;
7320 trans = btrfs_join_transaction(root);
7322 return PTR_ERR(trans);
7324 alloc_flags = update_block_group_flags(root, cache->flags);
7325 if (alloc_flags != cache->flags) {
7326 ret = do_chunk_alloc(trans, root, alloc_flags,
7332 ret = set_block_group_ro(cache, 0);
7335 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
7336 ret = do_chunk_alloc(trans, root, alloc_flags,
7340 ret = set_block_group_ro(cache, 0);
7342 btrfs_end_transaction(trans, root);
7346 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
7347 struct btrfs_root *root, u64 type)
7349 u64 alloc_flags = get_alloc_profile(root, type);
7350 return do_chunk_alloc(trans, root, alloc_flags,
7355 * helper to account the unused space of all the readonly block group in the
7356 * list. takes mirrors into account.
7358 static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
7360 struct btrfs_block_group_cache *block_group;
7364 list_for_each_entry(block_group, groups_list, list) {
7365 spin_lock(&block_group->lock);
7367 if (!block_group->ro) {
7368 spin_unlock(&block_group->lock);
7372 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
7373 BTRFS_BLOCK_GROUP_RAID10 |
7374 BTRFS_BLOCK_GROUP_DUP))
7379 free_bytes += (block_group->key.offset -
7380 btrfs_block_group_used(&block_group->item)) *
7383 spin_unlock(&block_group->lock);
7390 * helper to account the unused space of all the readonly block group in the
7391 * space_info. takes mirrors into account.
7393 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
7398 spin_lock(&sinfo->lock);
7400 for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
7401 if (!list_empty(&sinfo->block_groups[i]))
7402 free_bytes += __btrfs_get_ro_block_group_free_space(
7403 &sinfo->block_groups[i]);
7405 spin_unlock(&sinfo->lock);
7410 void btrfs_set_block_group_rw(struct btrfs_root *root,
7411 struct btrfs_block_group_cache *cache)
7413 struct btrfs_space_info *sinfo = cache->space_info;
7418 spin_lock(&sinfo->lock);
7419 spin_lock(&cache->lock);
7420 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7421 cache->bytes_super - btrfs_block_group_used(&cache->item);
7422 sinfo->bytes_readonly -= num_bytes;
7424 spin_unlock(&cache->lock);
7425 spin_unlock(&sinfo->lock);
7429 * checks to see if its even possible to relocate this block group.
7431 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
7432 * ok to go ahead and try.
7434 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
7436 struct btrfs_block_group_cache *block_group;
7437 struct btrfs_space_info *space_info;
7438 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
7439 struct btrfs_device *device;
7448 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
7450 /* odd, couldn't find the block group, leave it alone */
7454 min_free = btrfs_block_group_used(&block_group->item);
7456 /* no bytes used, we're good */
7460 space_info = block_group->space_info;
7461 spin_lock(&space_info->lock);
7463 full = space_info->full;
7466 * if this is the last block group we have in this space, we can't
7467 * relocate it unless we're able to allocate a new chunk below.
7469 * Otherwise, we need to make sure we have room in the space to handle
7470 * all of the extents from this block group. If we can, we're good
7472 if ((space_info->total_bytes != block_group->key.offset) &&
7473 (space_info->bytes_used + space_info->bytes_reserved +
7474 space_info->bytes_pinned + space_info->bytes_readonly +
7475 min_free < space_info->total_bytes)) {
7476 spin_unlock(&space_info->lock);
7479 spin_unlock(&space_info->lock);
7482 * ok we don't have enough space, but maybe we have free space on our
7483 * devices to allocate new chunks for relocation, so loop through our
7484 * alloc devices and guess if we have enough space. if this block
7485 * group is going to be restriped, run checks against the target
7486 * profile instead of the current one.
7498 target = get_restripe_target(root->fs_info, block_group->flags);
7500 index = __get_raid_index(extended_to_chunk(target));
7503 * this is just a balance, so if we were marked as full
7504 * we know there is no space for a new chunk
7509 index = get_block_group_index(block_group);
7516 } else if (index == 1) {
7518 } else if (index == 2) {
7521 } else if (index == 3) {
7522 dev_min = fs_devices->rw_devices;
7523 do_div(min_free, dev_min);
7526 mutex_lock(&root->fs_info->chunk_mutex);
7527 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
7531 * check to make sure we can actually find a chunk with enough
7532 * space to fit our block group in.
7534 if (device->total_bytes > device->bytes_used + min_free &&
7535 !device->is_tgtdev_for_dev_replace) {
7536 ret = find_free_dev_extent(device, min_free,
7541 if (dev_nr >= dev_min)
7547 mutex_unlock(&root->fs_info->chunk_mutex);
7549 btrfs_put_block_group(block_group);
7553 static int find_first_block_group(struct btrfs_root *root,
7554 struct btrfs_path *path, struct btrfs_key *key)
7557 struct btrfs_key found_key;
7558 struct extent_buffer *leaf;
7561 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
7566 slot = path->slots[0];
7567 leaf = path->nodes[0];
7568 if (slot >= btrfs_header_nritems(leaf)) {
7569 ret = btrfs_next_leaf(root, path);
7576 btrfs_item_key_to_cpu(leaf, &found_key, slot);
7578 if (found_key.objectid >= key->objectid &&
7579 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
7589 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
7591 struct btrfs_block_group_cache *block_group;
7595 struct inode *inode;
7597 block_group = btrfs_lookup_first_block_group(info, last);
7598 while (block_group) {
7599 spin_lock(&block_group->lock);
7600 if (block_group->iref)
7602 spin_unlock(&block_group->lock);
7603 block_group = next_block_group(info->tree_root,
7613 inode = block_group->inode;
7614 block_group->iref = 0;
7615 block_group->inode = NULL;
7616 spin_unlock(&block_group->lock);
7618 last = block_group->key.objectid + block_group->key.offset;
7619 btrfs_put_block_group(block_group);
7623 int btrfs_free_block_groups(struct btrfs_fs_info *info)
7625 struct btrfs_block_group_cache *block_group;
7626 struct btrfs_space_info *space_info;
7627 struct btrfs_caching_control *caching_ctl;
7630 down_write(&info->extent_commit_sem);
7631 while (!list_empty(&info->caching_block_groups)) {
7632 caching_ctl = list_entry(info->caching_block_groups.next,
7633 struct btrfs_caching_control, list);
7634 list_del(&caching_ctl->list);
7635 put_caching_control(caching_ctl);
7637 up_write(&info->extent_commit_sem);
7639 spin_lock(&info->block_group_cache_lock);
7640 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
7641 block_group = rb_entry(n, struct btrfs_block_group_cache,
7643 rb_erase(&block_group->cache_node,
7644 &info->block_group_cache_tree);
7645 spin_unlock(&info->block_group_cache_lock);
7647 down_write(&block_group->space_info->groups_sem);
7648 list_del(&block_group->list);
7649 up_write(&block_group->space_info->groups_sem);
7651 if (block_group->cached == BTRFS_CACHE_STARTED)
7652 wait_block_group_cache_done(block_group);
7655 * We haven't cached this block group, which means we could
7656 * possibly have excluded extents on this block group.
7658 if (block_group->cached == BTRFS_CACHE_NO)
7659 free_excluded_extents(info->extent_root, block_group);
7661 btrfs_remove_free_space_cache(block_group);
7662 btrfs_put_block_group(block_group);
7664 spin_lock(&info->block_group_cache_lock);
7666 spin_unlock(&info->block_group_cache_lock);
7668 /* now that all the block groups are freed, go through and
7669 * free all the space_info structs. This is only called during
7670 * the final stages of unmount, and so we know nobody is
7671 * using them. We call synchronize_rcu() once before we start,
7672 * just to be on the safe side.
7676 release_global_block_rsv(info);
7678 while(!list_empty(&info->space_info)) {
7679 space_info = list_entry(info->space_info.next,
7680 struct btrfs_space_info,
7682 if (space_info->bytes_pinned > 0 ||
7683 space_info->bytes_reserved > 0 ||
7684 space_info->bytes_may_use > 0) {
7686 dump_space_info(space_info, 0, 0);
7688 list_del(&space_info->list);
7694 static void __link_block_group(struct btrfs_space_info *space_info,
7695 struct btrfs_block_group_cache *cache)
7697 int index = get_block_group_index(cache);
7699 down_write(&space_info->groups_sem);
7700 list_add_tail(&cache->list, &space_info->block_groups[index]);
7701 up_write(&space_info->groups_sem);
7704 int btrfs_read_block_groups(struct btrfs_root *root)
7706 struct btrfs_path *path;
7708 struct btrfs_block_group_cache *cache;
7709 struct btrfs_fs_info *info = root->fs_info;
7710 struct btrfs_space_info *space_info;
7711 struct btrfs_key key;
7712 struct btrfs_key found_key;
7713 struct extent_buffer *leaf;
7717 root = info->extent_root;
7720 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
7721 path = btrfs_alloc_path();
7726 cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
7727 if (btrfs_test_opt(root, SPACE_CACHE) &&
7728 btrfs_super_generation(root->fs_info->super_copy) != cache_gen)
7730 if (btrfs_test_opt(root, CLEAR_CACHE))
7734 ret = find_first_block_group(root, path, &key);
7739 leaf = path->nodes[0];
7740 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
7741 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7746 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7748 if (!cache->free_space_ctl) {
7754 atomic_set(&cache->count, 1);
7755 spin_lock_init(&cache->lock);
7756 cache->fs_info = info;
7757 INIT_LIST_HEAD(&cache->list);
7758 INIT_LIST_HEAD(&cache->cluster_list);
7762 * When we mount with old space cache, we need to
7763 * set BTRFS_DC_CLEAR and set dirty flag.
7765 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
7766 * truncate the old free space cache inode and
7768 * b) Setting 'dirty flag' makes sure that we flush
7769 * the new space cache info onto disk.
7771 cache->disk_cache_state = BTRFS_DC_CLEAR;
7772 if (btrfs_test_opt(root, SPACE_CACHE))
7776 read_extent_buffer(leaf, &cache->item,
7777 btrfs_item_ptr_offset(leaf, path->slots[0]),
7778 sizeof(cache->item));
7779 memcpy(&cache->key, &found_key, sizeof(found_key));
7781 key.objectid = found_key.objectid + found_key.offset;
7782 btrfs_release_path(path);
7783 cache->flags = btrfs_block_group_flags(&cache->item);
7784 cache->sectorsize = root->sectorsize;
7786 btrfs_init_free_space_ctl(cache);
7789 * We need to exclude the super stripes now so that the space
7790 * info has super bytes accounted for, otherwise we'll think
7791 * we have more space than we actually do.
7793 exclude_super_stripes(root, cache);
7796 * check for two cases, either we are full, and therefore
7797 * don't need to bother with the caching work since we won't
7798 * find any space, or we are empty, and we can just add all
7799 * the space in and be done with it. This saves us _alot_ of
7800 * time, particularly in the full case.
7802 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
7803 cache->last_byte_to_unpin = (u64)-1;
7804 cache->cached = BTRFS_CACHE_FINISHED;
7805 free_excluded_extents(root, cache);
7806 } else if (btrfs_block_group_used(&cache->item) == 0) {
7807 cache->last_byte_to_unpin = (u64)-1;
7808 cache->cached = BTRFS_CACHE_FINISHED;
7809 add_new_free_space(cache, root->fs_info,
7811 found_key.objectid +
7813 free_excluded_extents(root, cache);
7816 ret = update_space_info(info, cache->flags, found_key.offset,
7817 btrfs_block_group_used(&cache->item),
7819 BUG_ON(ret); /* -ENOMEM */
7820 cache->space_info = space_info;
7821 spin_lock(&cache->space_info->lock);
7822 cache->space_info->bytes_readonly += cache->bytes_super;
7823 spin_unlock(&cache->space_info->lock);
7825 __link_block_group(space_info, cache);
7827 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7828 BUG_ON(ret); /* Logic error */
7830 set_avail_alloc_bits(root->fs_info, cache->flags);
7831 if (btrfs_chunk_readonly(root, cache->key.objectid))
7832 set_block_group_ro(cache, 1);
7835 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
7836 if (!(get_alloc_profile(root, space_info->flags) &
7837 (BTRFS_BLOCK_GROUP_RAID10 |
7838 BTRFS_BLOCK_GROUP_RAID1 |
7839 BTRFS_BLOCK_GROUP_DUP)))
7842 * avoid allocating from un-mirrored block group if there are
7843 * mirrored block groups.
7845 list_for_each_entry(cache, &space_info->block_groups[3], list)
7846 set_block_group_ro(cache, 1);
7847 list_for_each_entry(cache, &space_info->block_groups[4], list)
7848 set_block_group_ro(cache, 1);
7851 init_global_block_rsv(info);
7854 btrfs_free_path(path);
7858 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans,
7859 struct btrfs_root *root)
7861 struct btrfs_block_group_cache *block_group, *tmp;
7862 struct btrfs_root *extent_root = root->fs_info->extent_root;
7863 struct btrfs_block_group_item item;
7864 struct btrfs_key key;
7867 list_for_each_entry_safe(block_group, tmp, &trans->new_bgs,
7869 list_del_init(&block_group->new_bg_list);
7874 spin_lock(&block_group->lock);
7875 memcpy(&item, &block_group->item, sizeof(item));
7876 memcpy(&key, &block_group->key, sizeof(key));
7877 spin_unlock(&block_group->lock);
7879 ret = btrfs_insert_item(trans, extent_root, &key, &item,
7882 btrfs_abort_transaction(trans, extent_root, ret);
7886 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7887 struct btrfs_root *root, u64 bytes_used,
7888 u64 type, u64 chunk_objectid, u64 chunk_offset,
7892 struct btrfs_root *extent_root;
7893 struct btrfs_block_group_cache *cache;
7895 extent_root = root->fs_info->extent_root;
7897 root->fs_info->last_trans_log_full_commit = trans->transid;
7899 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7902 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7904 if (!cache->free_space_ctl) {
7909 cache->key.objectid = chunk_offset;
7910 cache->key.offset = size;
7911 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7912 cache->sectorsize = root->sectorsize;
7913 cache->fs_info = root->fs_info;
7915 atomic_set(&cache->count, 1);
7916 spin_lock_init(&cache->lock);
7917 INIT_LIST_HEAD(&cache->list);
7918 INIT_LIST_HEAD(&cache->cluster_list);
7919 INIT_LIST_HEAD(&cache->new_bg_list);
7921 btrfs_init_free_space_ctl(cache);
7923 btrfs_set_block_group_used(&cache->item, bytes_used);
7924 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7925 cache->flags = type;
7926 btrfs_set_block_group_flags(&cache->item, type);
7928 cache->last_byte_to_unpin = (u64)-1;
7929 cache->cached = BTRFS_CACHE_FINISHED;
7930 exclude_super_stripes(root, cache);
7932 add_new_free_space(cache, root->fs_info, chunk_offset,
7933 chunk_offset + size);
7935 free_excluded_extents(root, cache);
7937 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7938 &cache->space_info);
7939 BUG_ON(ret); /* -ENOMEM */
7940 update_global_block_rsv(root->fs_info);
7942 spin_lock(&cache->space_info->lock);
7943 cache->space_info->bytes_readonly += cache->bytes_super;
7944 spin_unlock(&cache->space_info->lock);
7946 __link_block_group(cache->space_info, cache);
7948 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7949 BUG_ON(ret); /* Logic error */
7951 list_add_tail(&cache->new_bg_list, &trans->new_bgs);
7953 set_avail_alloc_bits(extent_root->fs_info, type);
7958 static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
7960 u64 extra_flags = chunk_to_extended(flags) &
7961 BTRFS_EXTENDED_PROFILE_MASK;
7963 if (flags & BTRFS_BLOCK_GROUP_DATA)
7964 fs_info->avail_data_alloc_bits &= ~extra_flags;
7965 if (flags & BTRFS_BLOCK_GROUP_METADATA)
7966 fs_info->avail_metadata_alloc_bits &= ~extra_flags;
7967 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
7968 fs_info->avail_system_alloc_bits &= ~extra_flags;
7971 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7972 struct btrfs_root *root, u64 group_start)
7974 struct btrfs_path *path;
7975 struct btrfs_block_group_cache *block_group;
7976 struct btrfs_free_cluster *cluster;
7977 struct btrfs_root *tree_root = root->fs_info->tree_root;
7978 struct btrfs_key key;
7979 struct inode *inode;
7984 root = root->fs_info->extent_root;
7986 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7987 BUG_ON(!block_group);
7988 BUG_ON(!block_group->ro);
7991 * Free the reserved super bytes from this block group before
7994 free_excluded_extents(root, block_group);
7996 memcpy(&key, &block_group->key, sizeof(key));
7997 index = get_block_group_index(block_group);
7998 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
7999 BTRFS_BLOCK_GROUP_RAID1 |
8000 BTRFS_BLOCK_GROUP_RAID10))
8005 /* make sure this block group isn't part of an allocation cluster */
8006 cluster = &root->fs_info->data_alloc_cluster;
8007 spin_lock(&cluster->refill_lock);
8008 btrfs_return_cluster_to_free_space(block_group, cluster);
8009 spin_unlock(&cluster->refill_lock);
8012 * make sure this block group isn't part of a metadata
8013 * allocation cluster
8015 cluster = &root->fs_info->meta_alloc_cluster;
8016 spin_lock(&cluster->refill_lock);
8017 btrfs_return_cluster_to_free_space(block_group, cluster);
8018 spin_unlock(&cluster->refill_lock);
8020 path = btrfs_alloc_path();
8026 inode = lookup_free_space_inode(tree_root, block_group, path);
8027 if (!IS_ERR(inode)) {
8028 ret = btrfs_orphan_add(trans, inode);
8030 btrfs_add_delayed_iput(inode);
8034 /* One for the block groups ref */
8035 spin_lock(&block_group->lock);
8036 if (block_group->iref) {
8037 block_group->iref = 0;
8038 block_group->inode = NULL;
8039 spin_unlock(&block_group->lock);
8042 spin_unlock(&block_group->lock);
8044 /* One for our lookup ref */
8045 btrfs_add_delayed_iput(inode);
8048 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
8049 key.offset = block_group->key.objectid;
8052 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
8056 btrfs_release_path(path);
8058 ret = btrfs_del_item(trans, tree_root, path);
8061 btrfs_release_path(path);
8064 spin_lock(&root->fs_info->block_group_cache_lock);
8065 rb_erase(&block_group->cache_node,
8066 &root->fs_info->block_group_cache_tree);
8067 spin_unlock(&root->fs_info->block_group_cache_lock);
8069 down_write(&block_group->space_info->groups_sem);
8071 * we must use list_del_init so people can check to see if they
8072 * are still on the list after taking the semaphore
8074 list_del_init(&block_group->list);
8075 if (list_empty(&block_group->space_info->block_groups[index]))
8076 clear_avail_alloc_bits(root->fs_info, block_group->flags);
8077 up_write(&block_group->space_info->groups_sem);
8079 if (block_group->cached == BTRFS_CACHE_STARTED)
8080 wait_block_group_cache_done(block_group);
8082 btrfs_remove_free_space_cache(block_group);
8084 spin_lock(&block_group->space_info->lock);
8085 block_group->space_info->total_bytes -= block_group->key.offset;
8086 block_group->space_info->bytes_readonly -= block_group->key.offset;
8087 block_group->space_info->disk_total -= block_group->key.offset * factor;
8088 spin_unlock(&block_group->space_info->lock);
8090 memcpy(&key, &block_group->key, sizeof(key));
8092 btrfs_clear_space_info_full(root->fs_info);
8094 btrfs_put_block_group(block_group);
8095 btrfs_put_block_group(block_group);
8097 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8103 ret = btrfs_del_item(trans, root, path);
8105 btrfs_free_path(path);
8109 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
8111 struct btrfs_space_info *space_info;
8112 struct btrfs_super_block *disk_super;
8118 disk_super = fs_info->super_copy;
8119 if (!btrfs_super_root(disk_super))
8122 features = btrfs_super_incompat_flags(disk_super);
8123 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
8126 flags = BTRFS_BLOCK_GROUP_SYSTEM;
8127 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
8132 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
8133 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
8135 flags = BTRFS_BLOCK_GROUP_METADATA;
8136 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
8140 flags = BTRFS_BLOCK_GROUP_DATA;
8141 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
8147 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
8149 return unpin_extent_range(root, start, end);
8152 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
8153 u64 num_bytes, u64 *actual_bytes)
8155 return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
8158 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
8160 struct btrfs_fs_info *fs_info = root->fs_info;
8161 struct btrfs_block_group_cache *cache = NULL;
8166 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
8170 * try to trim all FS space, our block group may start from non-zero.
8172 if (range->len == total_bytes)
8173 cache = btrfs_lookup_first_block_group(fs_info, range->start);
8175 cache = btrfs_lookup_block_group(fs_info, range->start);
8178 if (cache->key.objectid >= (range->start + range->len)) {
8179 btrfs_put_block_group(cache);
8183 start = max(range->start, cache->key.objectid);
8184 end = min(range->start + range->len,
8185 cache->key.objectid + cache->key.offset);
8187 if (end - start >= range->minlen) {
8188 if (!block_group_cache_done(cache)) {
8189 ret = cache_block_group(cache, NULL, root, 0);
8191 wait_block_group_cache_done(cache);
8193 ret = btrfs_trim_block_group(cache,
8199 trimmed += group_trimmed;
8201 btrfs_put_block_group(cache);
8206 cache = next_block_group(fs_info->tree_root, cache);
8209 range->len = trimmed;