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>
30 #include "print-tree.h"
31 #include "transaction.h"
34 #include "free-space-cache.h"
36 /* control flags for do_chunk_alloc's force field
37 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
38 * if we really need one.
40 * CHUNK_ALLOC_FORCE means it must try to allocate one
42 * CHUNK_ALLOC_LIMITED means to only try and allocate one
43 * if we have very few chunks already allocated. This is
44 * used as part of the clustering code to help make sure
45 * we have a good pool of storage to cluster in, without
46 * filling the FS with empty chunks
50 CHUNK_ALLOC_NO_FORCE = 0,
51 CHUNK_ALLOC_FORCE = 1,
52 CHUNK_ALLOC_LIMITED = 2,
55 static int update_block_group(struct btrfs_trans_handle *trans,
56 struct btrfs_root *root,
57 u64 bytenr, u64 num_bytes, int alloc);
58 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
59 struct btrfs_root *root,
60 u64 bytenr, u64 num_bytes, u64 parent,
61 u64 root_objectid, u64 owner_objectid,
62 u64 owner_offset, int refs_to_drop,
63 struct btrfs_delayed_extent_op *extra_op);
64 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
65 struct extent_buffer *leaf,
66 struct btrfs_extent_item *ei);
67 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
68 struct btrfs_root *root,
69 u64 parent, u64 root_objectid,
70 u64 flags, u64 owner, u64 offset,
71 struct btrfs_key *ins, int ref_mod);
72 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
73 struct btrfs_root *root,
74 u64 parent, u64 root_objectid,
75 u64 flags, struct btrfs_disk_key *key,
76 int level, struct btrfs_key *ins);
77 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
78 struct btrfs_root *extent_root, u64 alloc_bytes,
79 u64 flags, int force);
80 static int find_next_key(struct btrfs_path *path, int level,
81 struct btrfs_key *key);
82 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
83 int dump_block_groups);
86 block_group_cache_done(struct btrfs_block_group_cache *cache)
89 return cache->cached == BTRFS_CACHE_FINISHED;
92 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
94 return (cache->flags & bits) == bits;
97 static void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
99 atomic_inc(&cache->count);
102 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
104 if (atomic_dec_and_test(&cache->count)) {
105 WARN_ON(cache->pinned > 0);
106 WARN_ON(cache->reserved > 0);
107 WARN_ON(cache->reserved_pinned > 0);
108 kfree(cache->free_space_ctl);
114 * this adds the block group to the fs_info rb tree for the block group
117 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
118 struct btrfs_block_group_cache *block_group)
121 struct rb_node *parent = NULL;
122 struct btrfs_block_group_cache *cache;
124 spin_lock(&info->block_group_cache_lock);
125 p = &info->block_group_cache_tree.rb_node;
129 cache = rb_entry(parent, struct btrfs_block_group_cache,
131 if (block_group->key.objectid < cache->key.objectid) {
133 } else if (block_group->key.objectid > cache->key.objectid) {
136 spin_unlock(&info->block_group_cache_lock);
141 rb_link_node(&block_group->cache_node, parent, p);
142 rb_insert_color(&block_group->cache_node,
143 &info->block_group_cache_tree);
144 spin_unlock(&info->block_group_cache_lock);
150 * This will return the block group at or after bytenr if contains is 0, else
151 * it will return the block group that contains the bytenr
153 static struct btrfs_block_group_cache *
154 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
157 struct btrfs_block_group_cache *cache, *ret = NULL;
161 spin_lock(&info->block_group_cache_lock);
162 n = info->block_group_cache_tree.rb_node;
165 cache = rb_entry(n, struct btrfs_block_group_cache,
167 end = cache->key.objectid + cache->key.offset - 1;
168 start = cache->key.objectid;
170 if (bytenr < start) {
171 if (!contains && (!ret || start < ret->key.objectid))
174 } else if (bytenr > start) {
175 if (contains && bytenr <= end) {
186 btrfs_get_block_group(ret);
187 spin_unlock(&info->block_group_cache_lock);
192 static int add_excluded_extent(struct btrfs_root *root,
193 u64 start, u64 num_bytes)
195 u64 end = start + num_bytes - 1;
196 set_extent_bits(&root->fs_info->freed_extents[0],
197 start, end, EXTENT_UPTODATE, GFP_NOFS);
198 set_extent_bits(&root->fs_info->freed_extents[1],
199 start, end, EXTENT_UPTODATE, GFP_NOFS);
203 static void free_excluded_extents(struct btrfs_root *root,
204 struct btrfs_block_group_cache *cache)
208 start = cache->key.objectid;
209 end = start + cache->key.offset - 1;
211 clear_extent_bits(&root->fs_info->freed_extents[0],
212 start, end, EXTENT_UPTODATE, GFP_NOFS);
213 clear_extent_bits(&root->fs_info->freed_extents[1],
214 start, end, EXTENT_UPTODATE, GFP_NOFS);
217 static int exclude_super_stripes(struct btrfs_root *root,
218 struct btrfs_block_group_cache *cache)
225 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
226 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
227 cache->bytes_super += stripe_len;
228 ret = add_excluded_extent(root, cache->key.objectid,
233 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
234 bytenr = btrfs_sb_offset(i);
235 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
236 cache->key.objectid, bytenr,
237 0, &logical, &nr, &stripe_len);
241 cache->bytes_super += stripe_len;
242 ret = add_excluded_extent(root, logical[nr],
252 static struct btrfs_caching_control *
253 get_caching_control(struct btrfs_block_group_cache *cache)
255 struct btrfs_caching_control *ctl;
257 spin_lock(&cache->lock);
258 if (cache->cached != BTRFS_CACHE_STARTED) {
259 spin_unlock(&cache->lock);
263 /* We're loading it the fast way, so we don't have a caching_ctl. */
264 if (!cache->caching_ctl) {
265 spin_unlock(&cache->lock);
269 ctl = cache->caching_ctl;
270 atomic_inc(&ctl->count);
271 spin_unlock(&cache->lock);
275 static void put_caching_control(struct btrfs_caching_control *ctl)
277 if (atomic_dec_and_test(&ctl->count))
282 * this is only called by cache_block_group, since we could have freed extents
283 * we need to check the pinned_extents for any extents that can't be used yet
284 * since their free space will be released as soon as the transaction commits.
286 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
287 struct btrfs_fs_info *info, u64 start, u64 end)
289 u64 extent_start, extent_end, size, total_added = 0;
292 while (start < end) {
293 ret = find_first_extent_bit(info->pinned_extents, start,
294 &extent_start, &extent_end,
295 EXTENT_DIRTY | EXTENT_UPTODATE);
299 if (extent_start <= start) {
300 start = extent_end + 1;
301 } else if (extent_start > start && extent_start < end) {
302 size = extent_start - start;
304 ret = btrfs_add_free_space(block_group, start,
307 start = extent_end + 1;
316 ret = btrfs_add_free_space(block_group, start, size);
323 static noinline void caching_thread(struct btrfs_work *work)
325 struct btrfs_block_group_cache *block_group;
326 struct btrfs_fs_info *fs_info;
327 struct btrfs_caching_control *caching_ctl;
328 struct btrfs_root *extent_root;
329 struct btrfs_path *path;
330 struct extent_buffer *leaf;
331 struct btrfs_key key;
337 caching_ctl = container_of(work, struct btrfs_caching_control, work);
338 block_group = caching_ctl->block_group;
339 fs_info = block_group->fs_info;
340 extent_root = fs_info->extent_root;
342 path = btrfs_alloc_path();
346 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
349 * We don't want to deadlock with somebody trying to allocate a new
350 * extent for the extent root while also trying to search the extent
351 * root to add free space. So we skip locking and search the commit
352 * root, since its read-only
354 path->skip_locking = 1;
355 path->search_commit_root = 1;
360 key.type = BTRFS_EXTENT_ITEM_KEY;
362 mutex_lock(&caching_ctl->mutex);
363 /* need to make sure the commit_root doesn't disappear */
364 down_read(&fs_info->extent_commit_sem);
366 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
370 leaf = path->nodes[0];
371 nritems = btrfs_header_nritems(leaf);
374 if (btrfs_fs_closing(fs_info) > 1) {
379 if (path->slots[0] < nritems) {
380 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
382 ret = find_next_key(path, 0, &key);
386 if (need_resched() ||
387 btrfs_next_leaf(extent_root, path)) {
388 caching_ctl->progress = last;
389 btrfs_release_path(path);
390 up_read(&fs_info->extent_commit_sem);
391 mutex_unlock(&caching_ctl->mutex);
395 leaf = path->nodes[0];
396 nritems = btrfs_header_nritems(leaf);
400 if (key.objectid < block_group->key.objectid) {
405 if (key.objectid >= block_group->key.objectid +
406 block_group->key.offset)
409 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
410 total_found += add_new_free_space(block_group,
413 last = key.objectid + key.offset;
415 if (total_found > (1024 * 1024 * 2)) {
417 wake_up(&caching_ctl->wait);
424 total_found += add_new_free_space(block_group, fs_info, last,
425 block_group->key.objectid +
426 block_group->key.offset);
427 caching_ctl->progress = (u64)-1;
429 spin_lock(&block_group->lock);
430 block_group->caching_ctl = NULL;
431 block_group->cached = BTRFS_CACHE_FINISHED;
432 spin_unlock(&block_group->lock);
435 btrfs_free_path(path);
436 up_read(&fs_info->extent_commit_sem);
438 free_excluded_extents(extent_root, block_group);
440 mutex_unlock(&caching_ctl->mutex);
442 wake_up(&caching_ctl->wait);
444 put_caching_control(caching_ctl);
445 btrfs_put_block_group(block_group);
448 static int cache_block_group(struct btrfs_block_group_cache *cache,
449 struct btrfs_trans_handle *trans,
450 struct btrfs_root *root,
453 struct btrfs_fs_info *fs_info = cache->fs_info;
454 struct btrfs_caching_control *caching_ctl;
458 if (cache->cached != BTRFS_CACHE_NO)
462 * We can't do the read from on-disk cache during a commit since we need
463 * to have the normal tree locking. Also if we are currently trying to
464 * allocate blocks for the tree root we can't do the fast caching since
465 * we likely hold important locks.
467 if (trans && (!trans->transaction->in_commit) &&
468 (root && root != root->fs_info->tree_root)) {
469 spin_lock(&cache->lock);
470 if (cache->cached != BTRFS_CACHE_NO) {
471 spin_unlock(&cache->lock);
474 cache->cached = BTRFS_CACHE_STARTED;
475 spin_unlock(&cache->lock);
477 ret = load_free_space_cache(fs_info, cache);
479 spin_lock(&cache->lock);
481 cache->cached = BTRFS_CACHE_FINISHED;
482 cache->last_byte_to_unpin = (u64)-1;
484 cache->cached = BTRFS_CACHE_NO;
486 spin_unlock(&cache->lock);
488 free_excluded_extents(fs_info->extent_root, cache);
496 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
497 BUG_ON(!caching_ctl);
499 INIT_LIST_HEAD(&caching_ctl->list);
500 mutex_init(&caching_ctl->mutex);
501 init_waitqueue_head(&caching_ctl->wait);
502 caching_ctl->block_group = cache;
503 caching_ctl->progress = cache->key.objectid;
504 /* one for caching kthread, one for caching block group list */
505 atomic_set(&caching_ctl->count, 2);
506 caching_ctl->work.func = caching_thread;
508 spin_lock(&cache->lock);
509 if (cache->cached != BTRFS_CACHE_NO) {
510 spin_unlock(&cache->lock);
514 cache->caching_ctl = caching_ctl;
515 cache->cached = BTRFS_CACHE_STARTED;
516 spin_unlock(&cache->lock);
518 down_write(&fs_info->extent_commit_sem);
519 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
520 up_write(&fs_info->extent_commit_sem);
522 btrfs_get_block_group(cache);
524 btrfs_queue_worker(&fs_info->caching_workers, &caching_ctl->work);
530 * return the block group that starts at or after bytenr
532 static struct btrfs_block_group_cache *
533 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
535 struct btrfs_block_group_cache *cache;
537 cache = block_group_cache_tree_search(info, bytenr, 0);
543 * return the block group that contains the given bytenr
545 struct btrfs_block_group_cache *btrfs_lookup_block_group(
546 struct btrfs_fs_info *info,
549 struct btrfs_block_group_cache *cache;
551 cache = block_group_cache_tree_search(info, bytenr, 1);
556 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
559 struct list_head *head = &info->space_info;
560 struct btrfs_space_info *found;
562 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
563 BTRFS_BLOCK_GROUP_METADATA;
566 list_for_each_entry_rcu(found, head, list) {
567 if (found->flags & flags) {
577 * after adding space to the filesystem, we need to clear the full flags
578 * on all the space infos.
580 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
582 struct list_head *head = &info->space_info;
583 struct btrfs_space_info *found;
586 list_for_each_entry_rcu(found, head, list)
591 static u64 div_factor(u64 num, int factor)
600 static u64 div_factor_fine(u64 num, int factor)
609 u64 btrfs_find_block_group(struct btrfs_root *root,
610 u64 search_start, u64 search_hint, int owner)
612 struct btrfs_block_group_cache *cache;
614 u64 last = max(search_hint, search_start);
621 cache = btrfs_lookup_first_block_group(root->fs_info, last);
625 spin_lock(&cache->lock);
626 last = cache->key.objectid + cache->key.offset;
627 used = btrfs_block_group_used(&cache->item);
629 if ((full_search || !cache->ro) &&
630 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
631 if (used + cache->pinned + cache->reserved <
632 div_factor(cache->key.offset, factor)) {
633 group_start = cache->key.objectid;
634 spin_unlock(&cache->lock);
635 btrfs_put_block_group(cache);
639 spin_unlock(&cache->lock);
640 btrfs_put_block_group(cache);
648 if (!full_search && factor < 10) {
658 /* simple helper to search for an existing extent at a given offset */
659 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
662 struct btrfs_key key;
663 struct btrfs_path *path;
665 path = btrfs_alloc_path();
669 key.objectid = start;
671 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
672 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
674 btrfs_free_path(path);
679 * helper function to lookup reference count and flags of extent.
681 * the head node for delayed ref is used to store the sum of all the
682 * reference count modifications queued up in the rbtree. the head
683 * node may also store the extent flags to set. This way you can check
684 * to see what the reference count and extent flags would be if all of
685 * the delayed refs are not processed.
687 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
688 struct btrfs_root *root, u64 bytenr,
689 u64 num_bytes, u64 *refs, u64 *flags)
691 struct btrfs_delayed_ref_head *head;
692 struct btrfs_delayed_ref_root *delayed_refs;
693 struct btrfs_path *path;
694 struct btrfs_extent_item *ei;
695 struct extent_buffer *leaf;
696 struct btrfs_key key;
702 path = btrfs_alloc_path();
706 key.objectid = bytenr;
707 key.type = BTRFS_EXTENT_ITEM_KEY;
708 key.offset = num_bytes;
710 path->skip_locking = 1;
711 path->search_commit_root = 1;
714 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
720 leaf = path->nodes[0];
721 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
722 if (item_size >= sizeof(*ei)) {
723 ei = btrfs_item_ptr(leaf, path->slots[0],
724 struct btrfs_extent_item);
725 num_refs = btrfs_extent_refs(leaf, ei);
726 extent_flags = btrfs_extent_flags(leaf, ei);
728 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
729 struct btrfs_extent_item_v0 *ei0;
730 BUG_ON(item_size != sizeof(*ei0));
731 ei0 = btrfs_item_ptr(leaf, path->slots[0],
732 struct btrfs_extent_item_v0);
733 num_refs = btrfs_extent_refs_v0(leaf, ei0);
734 /* FIXME: this isn't correct for data */
735 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
740 BUG_ON(num_refs == 0);
750 delayed_refs = &trans->transaction->delayed_refs;
751 spin_lock(&delayed_refs->lock);
752 head = btrfs_find_delayed_ref_head(trans, bytenr);
754 if (!mutex_trylock(&head->mutex)) {
755 atomic_inc(&head->node.refs);
756 spin_unlock(&delayed_refs->lock);
758 btrfs_release_path(path);
761 * Mutex was contended, block until it's released and try
764 mutex_lock(&head->mutex);
765 mutex_unlock(&head->mutex);
766 btrfs_put_delayed_ref(&head->node);
769 if (head->extent_op && head->extent_op->update_flags)
770 extent_flags |= head->extent_op->flags_to_set;
772 BUG_ON(num_refs == 0);
774 num_refs += head->node.ref_mod;
775 mutex_unlock(&head->mutex);
777 spin_unlock(&delayed_refs->lock);
779 WARN_ON(num_refs == 0);
783 *flags = extent_flags;
785 btrfs_free_path(path);
790 * Back reference rules. Back refs have three main goals:
792 * 1) differentiate between all holders of references to an extent so that
793 * when a reference is dropped we can make sure it was a valid reference
794 * before freeing the extent.
796 * 2) Provide enough information to quickly find the holders of an extent
797 * if we notice a given block is corrupted or bad.
799 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
800 * maintenance. This is actually the same as #2, but with a slightly
801 * different use case.
803 * There are two kinds of back refs. The implicit back refs is optimized
804 * for pointers in non-shared tree blocks. For a given pointer in a block,
805 * back refs of this kind provide information about the block's owner tree
806 * and the pointer's key. These information allow us to find the block by
807 * b-tree searching. The full back refs is for pointers in tree blocks not
808 * referenced by their owner trees. The location of tree block is recorded
809 * in the back refs. Actually the full back refs is generic, and can be
810 * used in all cases the implicit back refs is used. The major shortcoming
811 * of the full back refs is its overhead. Every time a tree block gets
812 * COWed, we have to update back refs entry for all pointers in it.
814 * For a newly allocated tree block, we use implicit back refs for
815 * pointers in it. This means most tree related operations only involve
816 * implicit back refs. For a tree block created in old transaction, the
817 * only way to drop a reference to it is COW it. So we can detect the
818 * event that tree block loses its owner tree's reference and do the
819 * back refs conversion.
821 * When a tree block is COW'd through a tree, there are four cases:
823 * The reference count of the block is one and the tree is the block's
824 * owner tree. Nothing to do in this case.
826 * The reference count of the block is one and the tree is not the
827 * block's owner tree. In this case, full back refs is used for pointers
828 * in the block. Remove these full back refs, add implicit back refs for
829 * every pointers in the new block.
831 * The reference count of the block is greater than one and the tree is
832 * the block's owner tree. In this case, implicit back refs is used for
833 * pointers in the block. Add full back refs for every pointers in the
834 * block, increase lower level extents' reference counts. The original
835 * implicit back refs are entailed to the new block.
837 * The reference count of the block is greater than one and the tree is
838 * not the block's owner tree. Add implicit back refs for every pointer in
839 * the new block, increase lower level extents' reference count.
841 * Back Reference Key composing:
843 * The key objectid corresponds to the first byte in the extent,
844 * The key type is used to differentiate between types of back refs.
845 * There are different meanings of the key offset for different types
848 * File extents can be referenced by:
850 * - multiple snapshots, subvolumes, or different generations in one subvol
851 * - different files inside a single subvolume
852 * - different offsets inside a file (bookend extents in file.c)
854 * The extent ref structure for the implicit back refs has fields for:
856 * - Objectid of the subvolume root
857 * - objectid of the file holding the reference
858 * - original offset in the file
859 * - how many bookend extents
861 * The key offset for the implicit back refs is hash of the first
864 * The extent ref structure for the full back refs has field for:
866 * - number of pointers in the tree leaf
868 * The key offset for the implicit back refs is the first byte of
871 * When a file extent is allocated, The implicit back refs is used.
872 * the fields are filled in:
874 * (root_key.objectid, inode objectid, offset in file, 1)
876 * When a file extent is removed file truncation, we find the
877 * corresponding implicit back refs and check the following fields:
879 * (btrfs_header_owner(leaf), inode objectid, offset in file)
881 * Btree extents can be referenced by:
883 * - Different subvolumes
885 * Both the implicit back refs and the full back refs for tree blocks
886 * only consist of key. The key offset for the implicit back refs is
887 * objectid of block's owner tree. The key offset for the full back refs
888 * is the first byte of parent block.
890 * When implicit back refs is used, information about the lowest key and
891 * level of the tree block are required. These information are stored in
892 * tree block info structure.
895 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
896 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
897 struct btrfs_root *root,
898 struct btrfs_path *path,
899 u64 owner, u32 extra_size)
901 struct btrfs_extent_item *item;
902 struct btrfs_extent_item_v0 *ei0;
903 struct btrfs_extent_ref_v0 *ref0;
904 struct btrfs_tree_block_info *bi;
905 struct extent_buffer *leaf;
906 struct btrfs_key key;
907 struct btrfs_key found_key;
908 u32 new_size = sizeof(*item);
912 leaf = path->nodes[0];
913 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
915 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
916 ei0 = btrfs_item_ptr(leaf, path->slots[0],
917 struct btrfs_extent_item_v0);
918 refs = btrfs_extent_refs_v0(leaf, ei0);
920 if (owner == (u64)-1) {
922 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
923 ret = btrfs_next_leaf(root, path);
927 leaf = path->nodes[0];
929 btrfs_item_key_to_cpu(leaf, &found_key,
931 BUG_ON(key.objectid != found_key.objectid);
932 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
936 ref0 = btrfs_item_ptr(leaf, path->slots[0],
937 struct btrfs_extent_ref_v0);
938 owner = btrfs_ref_objectid_v0(leaf, ref0);
942 btrfs_release_path(path);
944 if (owner < BTRFS_FIRST_FREE_OBJECTID)
945 new_size += sizeof(*bi);
947 new_size -= sizeof(*ei0);
948 ret = btrfs_search_slot(trans, root, &key, path,
949 new_size + extra_size, 1);
954 ret = btrfs_extend_item(trans, root, path, new_size);
956 leaf = path->nodes[0];
957 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
958 btrfs_set_extent_refs(leaf, item, refs);
959 /* FIXME: get real generation */
960 btrfs_set_extent_generation(leaf, item, 0);
961 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
962 btrfs_set_extent_flags(leaf, item,
963 BTRFS_EXTENT_FLAG_TREE_BLOCK |
964 BTRFS_BLOCK_FLAG_FULL_BACKREF);
965 bi = (struct btrfs_tree_block_info *)(item + 1);
966 /* FIXME: get first key of the block */
967 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
968 btrfs_set_tree_block_level(leaf, bi, (int)owner);
970 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
972 btrfs_mark_buffer_dirty(leaf);
977 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
979 u32 high_crc = ~(u32)0;
980 u32 low_crc = ~(u32)0;
983 lenum = cpu_to_le64(root_objectid);
984 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
985 lenum = cpu_to_le64(owner);
986 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
987 lenum = cpu_to_le64(offset);
988 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
990 return ((u64)high_crc << 31) ^ (u64)low_crc;
993 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
994 struct btrfs_extent_data_ref *ref)
996 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
997 btrfs_extent_data_ref_objectid(leaf, ref),
998 btrfs_extent_data_ref_offset(leaf, ref));
1001 static int match_extent_data_ref(struct extent_buffer *leaf,
1002 struct btrfs_extent_data_ref *ref,
1003 u64 root_objectid, u64 owner, u64 offset)
1005 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1006 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1007 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1012 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1013 struct btrfs_root *root,
1014 struct btrfs_path *path,
1015 u64 bytenr, u64 parent,
1017 u64 owner, u64 offset)
1019 struct btrfs_key key;
1020 struct btrfs_extent_data_ref *ref;
1021 struct extent_buffer *leaf;
1027 key.objectid = bytenr;
1029 key.type = BTRFS_SHARED_DATA_REF_KEY;
1030 key.offset = parent;
1032 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1033 key.offset = hash_extent_data_ref(root_objectid,
1038 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1047 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1048 key.type = BTRFS_EXTENT_REF_V0_KEY;
1049 btrfs_release_path(path);
1050 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1061 leaf = path->nodes[0];
1062 nritems = btrfs_header_nritems(leaf);
1064 if (path->slots[0] >= nritems) {
1065 ret = btrfs_next_leaf(root, path);
1071 leaf = path->nodes[0];
1072 nritems = btrfs_header_nritems(leaf);
1076 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1077 if (key.objectid != bytenr ||
1078 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1081 ref = btrfs_item_ptr(leaf, path->slots[0],
1082 struct btrfs_extent_data_ref);
1084 if (match_extent_data_ref(leaf, ref, root_objectid,
1087 btrfs_release_path(path);
1099 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1100 struct btrfs_root *root,
1101 struct btrfs_path *path,
1102 u64 bytenr, u64 parent,
1103 u64 root_objectid, u64 owner,
1104 u64 offset, int refs_to_add)
1106 struct btrfs_key key;
1107 struct extent_buffer *leaf;
1112 key.objectid = bytenr;
1114 key.type = BTRFS_SHARED_DATA_REF_KEY;
1115 key.offset = parent;
1116 size = sizeof(struct btrfs_shared_data_ref);
1118 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1119 key.offset = hash_extent_data_ref(root_objectid,
1121 size = sizeof(struct btrfs_extent_data_ref);
1124 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1125 if (ret && ret != -EEXIST)
1128 leaf = path->nodes[0];
1130 struct btrfs_shared_data_ref *ref;
1131 ref = btrfs_item_ptr(leaf, path->slots[0],
1132 struct btrfs_shared_data_ref);
1134 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1136 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1137 num_refs += refs_to_add;
1138 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1141 struct btrfs_extent_data_ref *ref;
1142 while (ret == -EEXIST) {
1143 ref = btrfs_item_ptr(leaf, path->slots[0],
1144 struct btrfs_extent_data_ref);
1145 if (match_extent_data_ref(leaf, ref, root_objectid,
1148 btrfs_release_path(path);
1150 ret = btrfs_insert_empty_item(trans, root, path, &key,
1152 if (ret && ret != -EEXIST)
1155 leaf = path->nodes[0];
1157 ref = btrfs_item_ptr(leaf, path->slots[0],
1158 struct btrfs_extent_data_ref);
1160 btrfs_set_extent_data_ref_root(leaf, ref,
1162 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1163 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1164 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1166 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1167 num_refs += refs_to_add;
1168 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1171 btrfs_mark_buffer_dirty(leaf);
1174 btrfs_release_path(path);
1178 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1179 struct btrfs_root *root,
1180 struct btrfs_path *path,
1183 struct btrfs_key key;
1184 struct btrfs_extent_data_ref *ref1 = NULL;
1185 struct btrfs_shared_data_ref *ref2 = NULL;
1186 struct extent_buffer *leaf;
1190 leaf = path->nodes[0];
1191 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1193 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1194 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1195 struct btrfs_extent_data_ref);
1196 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1197 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1198 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1199 struct btrfs_shared_data_ref);
1200 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1201 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1202 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1203 struct btrfs_extent_ref_v0 *ref0;
1204 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1205 struct btrfs_extent_ref_v0);
1206 num_refs = btrfs_ref_count_v0(leaf, ref0);
1212 BUG_ON(num_refs < refs_to_drop);
1213 num_refs -= refs_to_drop;
1215 if (num_refs == 0) {
1216 ret = btrfs_del_item(trans, root, path);
1218 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1219 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1220 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1221 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1222 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1224 struct btrfs_extent_ref_v0 *ref0;
1225 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1226 struct btrfs_extent_ref_v0);
1227 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1230 btrfs_mark_buffer_dirty(leaf);
1235 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1236 struct btrfs_path *path,
1237 struct btrfs_extent_inline_ref *iref)
1239 struct btrfs_key key;
1240 struct extent_buffer *leaf;
1241 struct btrfs_extent_data_ref *ref1;
1242 struct btrfs_shared_data_ref *ref2;
1245 leaf = path->nodes[0];
1246 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1248 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1249 BTRFS_EXTENT_DATA_REF_KEY) {
1250 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1251 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1253 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1254 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1256 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1257 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1258 struct btrfs_extent_data_ref);
1259 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1260 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1261 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1262 struct btrfs_shared_data_ref);
1263 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1264 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1265 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1266 struct btrfs_extent_ref_v0 *ref0;
1267 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1268 struct btrfs_extent_ref_v0);
1269 num_refs = btrfs_ref_count_v0(leaf, ref0);
1277 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1278 struct btrfs_root *root,
1279 struct btrfs_path *path,
1280 u64 bytenr, u64 parent,
1283 struct btrfs_key key;
1286 key.objectid = bytenr;
1288 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1289 key.offset = parent;
1291 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1292 key.offset = root_objectid;
1295 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1298 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1299 if (ret == -ENOENT && parent) {
1300 btrfs_release_path(path);
1301 key.type = BTRFS_EXTENT_REF_V0_KEY;
1302 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1310 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1311 struct btrfs_root *root,
1312 struct btrfs_path *path,
1313 u64 bytenr, u64 parent,
1316 struct btrfs_key key;
1319 key.objectid = bytenr;
1321 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1322 key.offset = parent;
1324 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1325 key.offset = root_objectid;
1328 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1329 btrfs_release_path(path);
1333 static inline int extent_ref_type(u64 parent, u64 owner)
1336 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1338 type = BTRFS_SHARED_BLOCK_REF_KEY;
1340 type = BTRFS_TREE_BLOCK_REF_KEY;
1343 type = BTRFS_SHARED_DATA_REF_KEY;
1345 type = BTRFS_EXTENT_DATA_REF_KEY;
1350 static int find_next_key(struct btrfs_path *path, int level,
1351 struct btrfs_key *key)
1354 for (; level < BTRFS_MAX_LEVEL; level++) {
1355 if (!path->nodes[level])
1357 if (path->slots[level] + 1 >=
1358 btrfs_header_nritems(path->nodes[level]))
1361 btrfs_item_key_to_cpu(path->nodes[level], key,
1362 path->slots[level] + 1);
1364 btrfs_node_key_to_cpu(path->nodes[level], key,
1365 path->slots[level] + 1);
1372 * look for inline back ref. if back ref is found, *ref_ret is set
1373 * to the address of inline back ref, and 0 is returned.
1375 * if back ref isn't found, *ref_ret is set to the address where it
1376 * should be inserted, and -ENOENT is returned.
1378 * if insert is true and there are too many inline back refs, the path
1379 * points to the extent item, and -EAGAIN is returned.
1381 * NOTE: inline back refs are ordered in the same way that back ref
1382 * items in the tree are ordered.
1384 static noinline_for_stack
1385 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1386 struct btrfs_root *root,
1387 struct btrfs_path *path,
1388 struct btrfs_extent_inline_ref **ref_ret,
1389 u64 bytenr, u64 num_bytes,
1390 u64 parent, u64 root_objectid,
1391 u64 owner, u64 offset, int insert)
1393 struct btrfs_key key;
1394 struct extent_buffer *leaf;
1395 struct btrfs_extent_item *ei;
1396 struct btrfs_extent_inline_ref *iref;
1407 key.objectid = bytenr;
1408 key.type = BTRFS_EXTENT_ITEM_KEY;
1409 key.offset = num_bytes;
1411 want = extent_ref_type(parent, owner);
1413 extra_size = btrfs_extent_inline_ref_size(want);
1414 path->keep_locks = 1;
1417 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1424 leaf = path->nodes[0];
1425 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1426 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1427 if (item_size < sizeof(*ei)) {
1432 ret = convert_extent_item_v0(trans, root, path, owner,
1438 leaf = path->nodes[0];
1439 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1442 BUG_ON(item_size < sizeof(*ei));
1444 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1445 flags = btrfs_extent_flags(leaf, ei);
1447 ptr = (unsigned long)(ei + 1);
1448 end = (unsigned long)ei + item_size;
1450 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1451 ptr += sizeof(struct btrfs_tree_block_info);
1454 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1463 iref = (struct btrfs_extent_inline_ref *)ptr;
1464 type = btrfs_extent_inline_ref_type(leaf, iref);
1468 ptr += btrfs_extent_inline_ref_size(type);
1472 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1473 struct btrfs_extent_data_ref *dref;
1474 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1475 if (match_extent_data_ref(leaf, dref, root_objectid,
1480 if (hash_extent_data_ref_item(leaf, dref) <
1481 hash_extent_data_ref(root_objectid, owner, offset))
1485 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1487 if (parent == ref_offset) {
1491 if (ref_offset < parent)
1494 if (root_objectid == ref_offset) {
1498 if (ref_offset < root_objectid)
1502 ptr += btrfs_extent_inline_ref_size(type);
1504 if (err == -ENOENT && insert) {
1505 if (item_size + extra_size >=
1506 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1511 * To add new inline back ref, we have to make sure
1512 * there is no corresponding back ref item.
1513 * For simplicity, we just do not add new inline back
1514 * ref if there is any kind of item for this block
1516 if (find_next_key(path, 0, &key) == 0 &&
1517 key.objectid == bytenr &&
1518 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1523 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1526 path->keep_locks = 0;
1527 btrfs_unlock_up_safe(path, 1);
1533 * helper to add new inline back ref
1535 static noinline_for_stack
1536 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1537 struct btrfs_root *root,
1538 struct btrfs_path *path,
1539 struct btrfs_extent_inline_ref *iref,
1540 u64 parent, u64 root_objectid,
1541 u64 owner, u64 offset, int refs_to_add,
1542 struct btrfs_delayed_extent_op *extent_op)
1544 struct extent_buffer *leaf;
1545 struct btrfs_extent_item *ei;
1548 unsigned long item_offset;
1554 leaf = path->nodes[0];
1555 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1556 item_offset = (unsigned long)iref - (unsigned long)ei;
1558 type = extent_ref_type(parent, owner);
1559 size = btrfs_extent_inline_ref_size(type);
1561 ret = btrfs_extend_item(trans, root, path, size);
1563 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1564 refs = btrfs_extent_refs(leaf, ei);
1565 refs += refs_to_add;
1566 btrfs_set_extent_refs(leaf, ei, refs);
1568 __run_delayed_extent_op(extent_op, leaf, ei);
1570 ptr = (unsigned long)ei + item_offset;
1571 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1572 if (ptr < end - size)
1573 memmove_extent_buffer(leaf, ptr + size, ptr,
1576 iref = (struct btrfs_extent_inline_ref *)ptr;
1577 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1578 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1579 struct btrfs_extent_data_ref *dref;
1580 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1581 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1582 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1583 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1584 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1585 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1586 struct btrfs_shared_data_ref *sref;
1587 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1588 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1589 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1590 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1591 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1593 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1595 btrfs_mark_buffer_dirty(leaf);
1599 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1600 struct btrfs_root *root,
1601 struct btrfs_path *path,
1602 struct btrfs_extent_inline_ref **ref_ret,
1603 u64 bytenr, u64 num_bytes, u64 parent,
1604 u64 root_objectid, u64 owner, u64 offset)
1608 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1609 bytenr, num_bytes, parent,
1610 root_objectid, owner, offset, 0);
1614 btrfs_release_path(path);
1617 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1618 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1621 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1622 root_objectid, owner, offset);
1628 * helper to update/remove inline back ref
1630 static noinline_for_stack
1631 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1632 struct btrfs_root *root,
1633 struct btrfs_path *path,
1634 struct btrfs_extent_inline_ref *iref,
1636 struct btrfs_delayed_extent_op *extent_op)
1638 struct extent_buffer *leaf;
1639 struct btrfs_extent_item *ei;
1640 struct btrfs_extent_data_ref *dref = NULL;
1641 struct btrfs_shared_data_ref *sref = NULL;
1650 leaf = path->nodes[0];
1651 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1652 refs = btrfs_extent_refs(leaf, ei);
1653 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1654 refs += refs_to_mod;
1655 btrfs_set_extent_refs(leaf, ei, refs);
1657 __run_delayed_extent_op(extent_op, leaf, ei);
1659 type = btrfs_extent_inline_ref_type(leaf, iref);
1661 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1662 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1663 refs = btrfs_extent_data_ref_count(leaf, dref);
1664 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1665 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1666 refs = btrfs_shared_data_ref_count(leaf, sref);
1669 BUG_ON(refs_to_mod != -1);
1672 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1673 refs += refs_to_mod;
1676 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1677 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1679 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1681 size = btrfs_extent_inline_ref_size(type);
1682 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1683 ptr = (unsigned long)iref;
1684 end = (unsigned long)ei + item_size;
1685 if (ptr + size < end)
1686 memmove_extent_buffer(leaf, ptr, ptr + size,
1689 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1691 btrfs_mark_buffer_dirty(leaf);
1695 static noinline_for_stack
1696 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1697 struct btrfs_root *root,
1698 struct btrfs_path *path,
1699 u64 bytenr, u64 num_bytes, u64 parent,
1700 u64 root_objectid, u64 owner,
1701 u64 offset, int refs_to_add,
1702 struct btrfs_delayed_extent_op *extent_op)
1704 struct btrfs_extent_inline_ref *iref;
1707 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1708 bytenr, num_bytes, parent,
1709 root_objectid, owner, offset, 1);
1711 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1712 ret = update_inline_extent_backref(trans, root, path, iref,
1713 refs_to_add, extent_op);
1714 } else if (ret == -ENOENT) {
1715 ret = setup_inline_extent_backref(trans, root, path, iref,
1716 parent, root_objectid,
1717 owner, offset, refs_to_add,
1723 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1724 struct btrfs_root *root,
1725 struct btrfs_path *path,
1726 u64 bytenr, u64 parent, u64 root_objectid,
1727 u64 owner, u64 offset, int refs_to_add)
1730 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1731 BUG_ON(refs_to_add != 1);
1732 ret = insert_tree_block_ref(trans, root, path, bytenr,
1733 parent, root_objectid);
1735 ret = insert_extent_data_ref(trans, root, path, bytenr,
1736 parent, root_objectid,
1737 owner, offset, refs_to_add);
1742 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1743 struct btrfs_root *root,
1744 struct btrfs_path *path,
1745 struct btrfs_extent_inline_ref *iref,
1746 int refs_to_drop, int is_data)
1750 BUG_ON(!is_data && refs_to_drop != 1);
1752 ret = update_inline_extent_backref(trans, root, path, iref,
1753 -refs_to_drop, NULL);
1754 } else if (is_data) {
1755 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1757 ret = btrfs_del_item(trans, root, path);
1762 static int btrfs_issue_discard(struct block_device *bdev,
1765 return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0);
1768 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1769 u64 num_bytes, u64 *actual_bytes)
1772 u64 discarded_bytes = 0;
1773 struct btrfs_multi_bio *multi = NULL;
1776 /* Tell the block device(s) that the sectors can be discarded */
1777 ret = btrfs_map_block(&root->fs_info->mapping_tree, REQ_DISCARD,
1778 bytenr, &num_bytes, &multi, 0);
1780 struct btrfs_bio_stripe *stripe = multi->stripes;
1784 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1785 ret = btrfs_issue_discard(stripe->dev->bdev,
1789 discarded_bytes += stripe->length;
1790 else if (ret != -EOPNOTSUPP)
1795 if (discarded_bytes && ret == -EOPNOTSUPP)
1799 *actual_bytes = discarded_bytes;
1805 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1806 struct btrfs_root *root,
1807 u64 bytenr, u64 num_bytes, u64 parent,
1808 u64 root_objectid, u64 owner, u64 offset)
1811 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1812 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1814 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1815 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1816 parent, root_objectid, (int)owner,
1817 BTRFS_ADD_DELAYED_REF, NULL);
1819 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1820 parent, root_objectid, owner, offset,
1821 BTRFS_ADD_DELAYED_REF, NULL);
1826 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1827 struct btrfs_root *root,
1828 u64 bytenr, u64 num_bytes,
1829 u64 parent, u64 root_objectid,
1830 u64 owner, u64 offset, int refs_to_add,
1831 struct btrfs_delayed_extent_op *extent_op)
1833 struct btrfs_path *path;
1834 struct extent_buffer *leaf;
1835 struct btrfs_extent_item *item;
1840 path = btrfs_alloc_path();
1845 path->leave_spinning = 1;
1846 /* this will setup the path even if it fails to insert the back ref */
1847 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1848 path, bytenr, num_bytes, parent,
1849 root_objectid, owner, offset,
1850 refs_to_add, extent_op);
1854 if (ret != -EAGAIN) {
1859 leaf = path->nodes[0];
1860 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1861 refs = btrfs_extent_refs(leaf, item);
1862 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1864 __run_delayed_extent_op(extent_op, leaf, item);
1866 btrfs_mark_buffer_dirty(leaf);
1867 btrfs_release_path(path);
1870 path->leave_spinning = 1;
1872 /* now insert the actual backref */
1873 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1874 path, bytenr, parent, root_objectid,
1875 owner, offset, refs_to_add);
1878 btrfs_free_path(path);
1882 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1883 struct btrfs_root *root,
1884 struct btrfs_delayed_ref_node *node,
1885 struct btrfs_delayed_extent_op *extent_op,
1886 int insert_reserved)
1889 struct btrfs_delayed_data_ref *ref;
1890 struct btrfs_key ins;
1895 ins.objectid = node->bytenr;
1896 ins.offset = node->num_bytes;
1897 ins.type = BTRFS_EXTENT_ITEM_KEY;
1899 ref = btrfs_delayed_node_to_data_ref(node);
1900 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1901 parent = ref->parent;
1903 ref_root = ref->root;
1905 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1907 BUG_ON(extent_op->update_key);
1908 flags |= extent_op->flags_to_set;
1910 ret = alloc_reserved_file_extent(trans, root,
1911 parent, ref_root, flags,
1912 ref->objectid, ref->offset,
1913 &ins, node->ref_mod);
1914 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1915 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1916 node->num_bytes, parent,
1917 ref_root, ref->objectid,
1918 ref->offset, node->ref_mod,
1920 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1921 ret = __btrfs_free_extent(trans, root, node->bytenr,
1922 node->num_bytes, parent,
1923 ref_root, ref->objectid,
1924 ref->offset, node->ref_mod,
1932 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1933 struct extent_buffer *leaf,
1934 struct btrfs_extent_item *ei)
1936 u64 flags = btrfs_extent_flags(leaf, ei);
1937 if (extent_op->update_flags) {
1938 flags |= extent_op->flags_to_set;
1939 btrfs_set_extent_flags(leaf, ei, flags);
1942 if (extent_op->update_key) {
1943 struct btrfs_tree_block_info *bi;
1944 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1945 bi = (struct btrfs_tree_block_info *)(ei + 1);
1946 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1950 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1951 struct btrfs_root *root,
1952 struct btrfs_delayed_ref_node *node,
1953 struct btrfs_delayed_extent_op *extent_op)
1955 struct btrfs_key key;
1956 struct btrfs_path *path;
1957 struct btrfs_extent_item *ei;
1958 struct extent_buffer *leaf;
1963 path = btrfs_alloc_path();
1967 key.objectid = node->bytenr;
1968 key.type = BTRFS_EXTENT_ITEM_KEY;
1969 key.offset = node->num_bytes;
1972 path->leave_spinning = 1;
1973 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1984 leaf = path->nodes[0];
1985 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1986 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1987 if (item_size < sizeof(*ei)) {
1988 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1994 leaf = path->nodes[0];
1995 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1998 BUG_ON(item_size < sizeof(*ei));
1999 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2000 __run_delayed_extent_op(extent_op, leaf, ei);
2002 btrfs_mark_buffer_dirty(leaf);
2004 btrfs_free_path(path);
2008 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2009 struct btrfs_root *root,
2010 struct btrfs_delayed_ref_node *node,
2011 struct btrfs_delayed_extent_op *extent_op,
2012 int insert_reserved)
2015 struct btrfs_delayed_tree_ref *ref;
2016 struct btrfs_key ins;
2020 ins.objectid = node->bytenr;
2021 ins.offset = node->num_bytes;
2022 ins.type = BTRFS_EXTENT_ITEM_KEY;
2024 ref = btrfs_delayed_node_to_tree_ref(node);
2025 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2026 parent = ref->parent;
2028 ref_root = ref->root;
2030 BUG_ON(node->ref_mod != 1);
2031 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2032 BUG_ON(!extent_op || !extent_op->update_flags ||
2033 !extent_op->update_key);
2034 ret = alloc_reserved_tree_block(trans, root,
2036 extent_op->flags_to_set,
2039 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2040 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2041 node->num_bytes, parent, ref_root,
2042 ref->level, 0, 1, extent_op);
2043 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2044 ret = __btrfs_free_extent(trans, root, node->bytenr,
2045 node->num_bytes, parent, ref_root,
2046 ref->level, 0, 1, extent_op);
2053 /* helper function to actually process a single delayed ref entry */
2054 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2055 struct btrfs_root *root,
2056 struct btrfs_delayed_ref_node *node,
2057 struct btrfs_delayed_extent_op *extent_op,
2058 int insert_reserved)
2061 if (btrfs_delayed_ref_is_head(node)) {
2062 struct btrfs_delayed_ref_head *head;
2064 * we've hit the end of the chain and we were supposed
2065 * to insert this extent into the tree. But, it got
2066 * deleted before we ever needed to insert it, so all
2067 * we have to do is clean up the accounting
2070 head = btrfs_delayed_node_to_head(node);
2071 if (insert_reserved) {
2072 btrfs_pin_extent(root, node->bytenr,
2073 node->num_bytes, 1);
2074 if (head->is_data) {
2075 ret = btrfs_del_csums(trans, root,
2081 mutex_unlock(&head->mutex);
2085 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2086 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2087 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2089 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2090 node->type == BTRFS_SHARED_DATA_REF_KEY)
2091 ret = run_delayed_data_ref(trans, root, node, extent_op,
2098 static noinline struct btrfs_delayed_ref_node *
2099 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2101 struct rb_node *node;
2102 struct btrfs_delayed_ref_node *ref;
2103 int action = BTRFS_ADD_DELAYED_REF;
2106 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2107 * this prevents ref count from going down to zero when
2108 * there still are pending delayed ref.
2110 node = rb_prev(&head->node.rb_node);
2114 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2116 if (ref->bytenr != head->node.bytenr)
2118 if (ref->action == action)
2120 node = rb_prev(node);
2122 if (action == BTRFS_ADD_DELAYED_REF) {
2123 action = BTRFS_DROP_DELAYED_REF;
2129 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2130 struct btrfs_root *root,
2131 struct list_head *cluster)
2133 struct btrfs_delayed_ref_root *delayed_refs;
2134 struct btrfs_delayed_ref_node *ref;
2135 struct btrfs_delayed_ref_head *locked_ref = NULL;
2136 struct btrfs_delayed_extent_op *extent_op;
2139 int must_insert_reserved = 0;
2141 delayed_refs = &trans->transaction->delayed_refs;
2144 /* pick a new head ref from the cluster list */
2145 if (list_empty(cluster))
2148 locked_ref = list_entry(cluster->next,
2149 struct btrfs_delayed_ref_head, cluster);
2151 /* grab the lock that says we are going to process
2152 * all the refs for this head */
2153 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2156 * we may have dropped the spin lock to get the head
2157 * mutex lock, and that might have given someone else
2158 * time to free the head. If that's true, it has been
2159 * removed from our list and we can move on.
2161 if (ret == -EAGAIN) {
2169 * record the must insert reserved flag before we
2170 * drop the spin lock.
2172 must_insert_reserved = locked_ref->must_insert_reserved;
2173 locked_ref->must_insert_reserved = 0;
2175 extent_op = locked_ref->extent_op;
2176 locked_ref->extent_op = NULL;
2179 * locked_ref is the head node, so we have to go one
2180 * node back for any delayed ref updates
2182 ref = select_delayed_ref(locked_ref);
2184 /* All delayed refs have been processed, Go ahead
2185 * and send the head node to run_one_delayed_ref,
2186 * so that any accounting fixes can happen
2188 ref = &locked_ref->node;
2190 if (extent_op && must_insert_reserved) {
2196 spin_unlock(&delayed_refs->lock);
2198 ret = run_delayed_extent_op(trans, root,
2204 spin_lock(&delayed_refs->lock);
2208 list_del_init(&locked_ref->cluster);
2213 rb_erase(&ref->rb_node, &delayed_refs->root);
2214 delayed_refs->num_entries--;
2216 spin_unlock(&delayed_refs->lock);
2218 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2219 must_insert_reserved);
2222 btrfs_put_delayed_ref(ref);
2227 spin_lock(&delayed_refs->lock);
2233 * this starts processing the delayed reference count updates and
2234 * extent insertions we have queued up so far. count can be
2235 * 0, which means to process everything in the tree at the start
2236 * of the run (but not newly added entries), or it can be some target
2237 * number you'd like to process.
2239 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2240 struct btrfs_root *root, unsigned long count)
2242 struct rb_node *node;
2243 struct btrfs_delayed_ref_root *delayed_refs;
2244 struct btrfs_delayed_ref_node *ref;
2245 struct list_head cluster;
2247 int run_all = count == (unsigned long)-1;
2250 if (root == root->fs_info->extent_root)
2251 root = root->fs_info->tree_root;
2253 delayed_refs = &trans->transaction->delayed_refs;
2254 INIT_LIST_HEAD(&cluster);
2256 spin_lock(&delayed_refs->lock);
2258 count = delayed_refs->num_entries * 2;
2262 if (!(run_all || run_most) &&
2263 delayed_refs->num_heads_ready < 64)
2267 * go find something we can process in the rbtree. We start at
2268 * the beginning of the tree, and then build a cluster
2269 * of refs to process starting at the first one we are able to
2272 ret = btrfs_find_ref_cluster(trans, &cluster,
2273 delayed_refs->run_delayed_start);
2277 ret = run_clustered_refs(trans, root, &cluster);
2280 count -= min_t(unsigned long, ret, count);
2287 node = rb_first(&delayed_refs->root);
2290 count = (unsigned long)-1;
2293 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2295 if (btrfs_delayed_ref_is_head(ref)) {
2296 struct btrfs_delayed_ref_head *head;
2298 head = btrfs_delayed_node_to_head(ref);
2299 atomic_inc(&ref->refs);
2301 spin_unlock(&delayed_refs->lock);
2303 * Mutex was contended, block until it's
2304 * released and try again
2306 mutex_lock(&head->mutex);
2307 mutex_unlock(&head->mutex);
2309 btrfs_put_delayed_ref(ref);
2313 node = rb_next(node);
2315 spin_unlock(&delayed_refs->lock);
2316 schedule_timeout(1);
2320 spin_unlock(&delayed_refs->lock);
2324 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2325 struct btrfs_root *root,
2326 u64 bytenr, u64 num_bytes, u64 flags,
2329 struct btrfs_delayed_extent_op *extent_op;
2332 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2336 extent_op->flags_to_set = flags;
2337 extent_op->update_flags = 1;
2338 extent_op->update_key = 0;
2339 extent_op->is_data = is_data ? 1 : 0;
2341 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2347 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2348 struct btrfs_root *root,
2349 struct btrfs_path *path,
2350 u64 objectid, u64 offset, u64 bytenr)
2352 struct btrfs_delayed_ref_head *head;
2353 struct btrfs_delayed_ref_node *ref;
2354 struct btrfs_delayed_data_ref *data_ref;
2355 struct btrfs_delayed_ref_root *delayed_refs;
2356 struct rb_node *node;
2360 delayed_refs = &trans->transaction->delayed_refs;
2361 spin_lock(&delayed_refs->lock);
2362 head = btrfs_find_delayed_ref_head(trans, bytenr);
2366 if (!mutex_trylock(&head->mutex)) {
2367 atomic_inc(&head->node.refs);
2368 spin_unlock(&delayed_refs->lock);
2370 btrfs_release_path(path);
2373 * Mutex was contended, block until it's released and let
2376 mutex_lock(&head->mutex);
2377 mutex_unlock(&head->mutex);
2378 btrfs_put_delayed_ref(&head->node);
2382 node = rb_prev(&head->node.rb_node);
2386 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2388 if (ref->bytenr != bytenr)
2392 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2395 data_ref = btrfs_delayed_node_to_data_ref(ref);
2397 node = rb_prev(node);
2399 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2400 if (ref->bytenr == bytenr)
2404 if (data_ref->root != root->root_key.objectid ||
2405 data_ref->objectid != objectid || data_ref->offset != offset)
2410 mutex_unlock(&head->mutex);
2412 spin_unlock(&delayed_refs->lock);
2416 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2417 struct btrfs_root *root,
2418 struct btrfs_path *path,
2419 u64 objectid, u64 offset, u64 bytenr)
2421 struct btrfs_root *extent_root = root->fs_info->extent_root;
2422 struct extent_buffer *leaf;
2423 struct btrfs_extent_data_ref *ref;
2424 struct btrfs_extent_inline_ref *iref;
2425 struct btrfs_extent_item *ei;
2426 struct btrfs_key key;
2430 key.objectid = bytenr;
2431 key.offset = (u64)-1;
2432 key.type = BTRFS_EXTENT_ITEM_KEY;
2434 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2440 if (path->slots[0] == 0)
2444 leaf = path->nodes[0];
2445 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2447 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2451 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2452 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2453 if (item_size < sizeof(*ei)) {
2454 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2458 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2460 if (item_size != sizeof(*ei) +
2461 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2464 if (btrfs_extent_generation(leaf, ei) <=
2465 btrfs_root_last_snapshot(&root->root_item))
2468 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2469 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2470 BTRFS_EXTENT_DATA_REF_KEY)
2473 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2474 if (btrfs_extent_refs(leaf, ei) !=
2475 btrfs_extent_data_ref_count(leaf, ref) ||
2476 btrfs_extent_data_ref_root(leaf, ref) !=
2477 root->root_key.objectid ||
2478 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2479 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2487 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2488 struct btrfs_root *root,
2489 u64 objectid, u64 offset, u64 bytenr)
2491 struct btrfs_path *path;
2495 path = btrfs_alloc_path();
2500 ret = check_committed_ref(trans, root, path, objectid,
2502 if (ret && ret != -ENOENT)
2505 ret2 = check_delayed_ref(trans, root, path, objectid,
2507 } while (ret2 == -EAGAIN);
2509 if (ret2 && ret2 != -ENOENT) {
2514 if (ret != -ENOENT || ret2 != -ENOENT)
2517 btrfs_free_path(path);
2518 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2523 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2524 struct btrfs_root *root,
2525 struct extent_buffer *buf,
2526 int full_backref, int inc)
2533 struct btrfs_key key;
2534 struct btrfs_file_extent_item *fi;
2538 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2539 u64, u64, u64, u64, u64, u64);
2541 ref_root = btrfs_header_owner(buf);
2542 nritems = btrfs_header_nritems(buf);
2543 level = btrfs_header_level(buf);
2545 if (!root->ref_cows && level == 0)
2549 process_func = btrfs_inc_extent_ref;
2551 process_func = btrfs_free_extent;
2554 parent = buf->start;
2558 for (i = 0; i < nritems; i++) {
2560 btrfs_item_key_to_cpu(buf, &key, i);
2561 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2563 fi = btrfs_item_ptr(buf, i,
2564 struct btrfs_file_extent_item);
2565 if (btrfs_file_extent_type(buf, fi) ==
2566 BTRFS_FILE_EXTENT_INLINE)
2568 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2572 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2573 key.offset -= btrfs_file_extent_offset(buf, fi);
2574 ret = process_func(trans, root, bytenr, num_bytes,
2575 parent, ref_root, key.objectid,
2580 bytenr = btrfs_node_blockptr(buf, i);
2581 num_bytes = btrfs_level_size(root, level - 1);
2582 ret = process_func(trans, root, bytenr, num_bytes,
2583 parent, ref_root, level - 1, 0);
2594 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2595 struct extent_buffer *buf, int full_backref)
2597 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2600 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2601 struct extent_buffer *buf, int full_backref)
2603 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2606 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2607 struct btrfs_root *root,
2608 struct btrfs_path *path,
2609 struct btrfs_block_group_cache *cache)
2612 struct btrfs_root *extent_root = root->fs_info->extent_root;
2614 struct extent_buffer *leaf;
2616 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2621 leaf = path->nodes[0];
2622 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2623 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2624 btrfs_mark_buffer_dirty(leaf);
2625 btrfs_release_path(path);
2633 static struct btrfs_block_group_cache *
2634 next_block_group(struct btrfs_root *root,
2635 struct btrfs_block_group_cache *cache)
2637 struct rb_node *node;
2638 spin_lock(&root->fs_info->block_group_cache_lock);
2639 node = rb_next(&cache->cache_node);
2640 btrfs_put_block_group(cache);
2642 cache = rb_entry(node, struct btrfs_block_group_cache,
2644 btrfs_get_block_group(cache);
2647 spin_unlock(&root->fs_info->block_group_cache_lock);
2651 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2652 struct btrfs_trans_handle *trans,
2653 struct btrfs_path *path)
2655 struct btrfs_root *root = block_group->fs_info->tree_root;
2656 struct inode *inode = NULL;
2658 int dcs = BTRFS_DC_ERROR;
2664 * If this block group is smaller than 100 megs don't bother caching the
2667 if (block_group->key.offset < (100 * 1024 * 1024)) {
2668 spin_lock(&block_group->lock);
2669 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2670 spin_unlock(&block_group->lock);
2675 inode = lookup_free_space_inode(root, block_group, path);
2676 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2677 ret = PTR_ERR(inode);
2678 btrfs_release_path(path);
2682 if (IS_ERR(inode)) {
2686 if (block_group->ro)
2689 ret = create_free_space_inode(root, trans, block_group, path);
2696 * We want to set the generation to 0, that way if anything goes wrong
2697 * from here on out we know not to trust this cache when we load up next
2700 BTRFS_I(inode)->generation = 0;
2701 ret = btrfs_update_inode(trans, root, inode);
2704 if (i_size_read(inode) > 0) {
2705 ret = btrfs_truncate_free_space_cache(root, trans, path,
2711 spin_lock(&block_group->lock);
2712 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2713 /* We're not cached, don't bother trying to write stuff out */
2714 dcs = BTRFS_DC_WRITTEN;
2715 spin_unlock(&block_group->lock);
2718 spin_unlock(&block_group->lock);
2720 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2725 * Just to make absolutely sure we have enough space, we're going to
2726 * preallocate 12 pages worth of space for each block group. In
2727 * practice we ought to use at most 8, but we need extra space so we can
2728 * add our header and have a terminator between the extents and the
2732 num_pages *= PAGE_CACHE_SIZE;
2734 ret = btrfs_check_data_free_space(inode, num_pages);
2738 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2739 num_pages, num_pages,
2742 dcs = BTRFS_DC_SETUP;
2743 btrfs_free_reserved_data_space(inode, num_pages);
2747 btrfs_release_path(path);
2749 spin_lock(&block_group->lock);
2750 block_group->disk_cache_state = dcs;
2751 spin_unlock(&block_group->lock);
2756 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2757 struct btrfs_root *root)
2759 struct btrfs_block_group_cache *cache;
2761 struct btrfs_path *path;
2764 path = btrfs_alloc_path();
2770 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2772 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2774 cache = next_block_group(root, cache);
2782 err = cache_save_setup(cache, trans, path);
2783 last = cache->key.objectid + cache->key.offset;
2784 btrfs_put_block_group(cache);
2789 err = btrfs_run_delayed_refs(trans, root,
2794 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2796 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2797 btrfs_put_block_group(cache);
2803 cache = next_block_group(root, cache);
2812 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2813 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2815 last = cache->key.objectid + cache->key.offset;
2817 err = write_one_cache_group(trans, root, path, cache);
2819 btrfs_put_block_group(cache);
2824 * I don't think this is needed since we're just marking our
2825 * preallocated extent as written, but just in case it can't
2829 err = btrfs_run_delayed_refs(trans, root,
2834 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2837 * Really this shouldn't happen, but it could if we
2838 * couldn't write the entire preallocated extent and
2839 * splitting the extent resulted in a new block.
2842 btrfs_put_block_group(cache);
2845 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2847 cache = next_block_group(root, cache);
2856 btrfs_write_out_cache(root, trans, cache, path);
2859 * If we didn't have an error then the cache state is still
2860 * NEED_WRITE, so we can set it to WRITTEN.
2862 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2863 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2864 last = cache->key.objectid + cache->key.offset;
2865 btrfs_put_block_group(cache);
2868 btrfs_free_path(path);
2872 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2874 struct btrfs_block_group_cache *block_group;
2877 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2878 if (!block_group || block_group->ro)
2881 btrfs_put_block_group(block_group);
2885 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2886 u64 total_bytes, u64 bytes_used,
2887 struct btrfs_space_info **space_info)
2889 struct btrfs_space_info *found;
2893 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2894 BTRFS_BLOCK_GROUP_RAID10))
2899 found = __find_space_info(info, flags);
2901 spin_lock(&found->lock);
2902 found->total_bytes += total_bytes;
2903 found->disk_total += total_bytes * factor;
2904 found->bytes_used += bytes_used;
2905 found->disk_used += bytes_used * factor;
2907 spin_unlock(&found->lock);
2908 *space_info = found;
2911 found = kzalloc(sizeof(*found), GFP_NOFS);
2915 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
2916 INIT_LIST_HEAD(&found->block_groups[i]);
2917 init_rwsem(&found->groups_sem);
2918 spin_lock_init(&found->lock);
2919 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
2920 BTRFS_BLOCK_GROUP_SYSTEM |
2921 BTRFS_BLOCK_GROUP_METADATA);
2922 found->total_bytes = total_bytes;
2923 found->disk_total = total_bytes * factor;
2924 found->bytes_used = bytes_used;
2925 found->disk_used = bytes_used * factor;
2926 found->bytes_pinned = 0;
2927 found->bytes_reserved = 0;
2928 found->bytes_readonly = 0;
2929 found->bytes_may_use = 0;
2931 found->force_alloc = CHUNK_ALLOC_NO_FORCE;
2932 found->chunk_alloc = 0;
2934 init_waitqueue_head(&found->wait);
2935 *space_info = found;
2936 list_add_rcu(&found->list, &info->space_info);
2940 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
2942 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
2943 BTRFS_BLOCK_GROUP_RAID1 |
2944 BTRFS_BLOCK_GROUP_RAID10 |
2945 BTRFS_BLOCK_GROUP_DUP);
2947 if (flags & BTRFS_BLOCK_GROUP_DATA)
2948 fs_info->avail_data_alloc_bits |= extra_flags;
2949 if (flags & BTRFS_BLOCK_GROUP_METADATA)
2950 fs_info->avail_metadata_alloc_bits |= extra_flags;
2951 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
2952 fs_info->avail_system_alloc_bits |= extra_flags;
2956 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
2959 * we add in the count of missing devices because we want
2960 * to make sure that any RAID levels on a degraded FS
2961 * continue to be honored.
2963 u64 num_devices = root->fs_info->fs_devices->rw_devices +
2964 root->fs_info->fs_devices->missing_devices;
2966 if (num_devices == 1)
2967 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
2968 if (num_devices < 4)
2969 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
2971 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
2972 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
2973 BTRFS_BLOCK_GROUP_RAID10))) {
2974 flags &= ~BTRFS_BLOCK_GROUP_DUP;
2977 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
2978 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
2979 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
2982 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
2983 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
2984 (flags & BTRFS_BLOCK_GROUP_RAID10) |
2985 (flags & BTRFS_BLOCK_GROUP_DUP)))
2986 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
2990 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
2992 if (flags & BTRFS_BLOCK_GROUP_DATA)
2993 flags |= root->fs_info->avail_data_alloc_bits &
2994 root->fs_info->data_alloc_profile;
2995 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
2996 flags |= root->fs_info->avail_system_alloc_bits &
2997 root->fs_info->system_alloc_profile;
2998 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
2999 flags |= root->fs_info->avail_metadata_alloc_bits &
3000 root->fs_info->metadata_alloc_profile;
3001 return btrfs_reduce_alloc_profile(root, flags);
3004 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3009 flags = BTRFS_BLOCK_GROUP_DATA;
3010 else if (root == root->fs_info->chunk_root)
3011 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3013 flags = BTRFS_BLOCK_GROUP_METADATA;
3015 return get_alloc_profile(root, flags);
3018 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3020 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3021 BTRFS_BLOCK_GROUP_DATA);
3025 * This will check the space that the inode allocates from to make sure we have
3026 * enough space for bytes.
3028 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3030 struct btrfs_space_info *data_sinfo;
3031 struct btrfs_root *root = BTRFS_I(inode)->root;
3033 int ret = 0, committed = 0, alloc_chunk = 1;
3035 /* make sure bytes are sectorsize aligned */
3036 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3038 if (root == root->fs_info->tree_root ||
3039 BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID) {
3044 data_sinfo = BTRFS_I(inode)->space_info;
3049 /* make sure we have enough space to handle the data first */
3050 spin_lock(&data_sinfo->lock);
3051 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3052 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3053 data_sinfo->bytes_may_use;
3055 if (used + bytes > data_sinfo->total_bytes) {
3056 struct btrfs_trans_handle *trans;
3059 * if we don't have enough free bytes in this space then we need
3060 * to alloc a new chunk.
3062 if (!data_sinfo->full && alloc_chunk) {
3065 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
3066 spin_unlock(&data_sinfo->lock);
3068 alloc_target = btrfs_get_alloc_profile(root, 1);
3069 trans = btrfs_join_transaction(root);
3071 return PTR_ERR(trans);
3073 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3074 bytes + 2 * 1024 * 1024,
3076 CHUNK_ALLOC_NO_FORCE);
3077 btrfs_end_transaction(trans, root);
3086 btrfs_set_inode_space_info(root, inode);
3087 data_sinfo = BTRFS_I(inode)->space_info;
3093 * If we have less pinned bytes than we want to allocate then
3094 * don't bother committing the transaction, it won't help us.
3096 if (data_sinfo->bytes_pinned < bytes)
3098 spin_unlock(&data_sinfo->lock);
3100 /* commit the current transaction and try again */
3103 !atomic_read(&root->fs_info->open_ioctl_trans)) {
3105 trans = btrfs_join_transaction(root);
3107 return PTR_ERR(trans);
3108 ret = btrfs_commit_transaction(trans, root);
3116 data_sinfo->bytes_may_use += bytes;
3117 BTRFS_I(inode)->reserved_bytes += bytes;
3118 spin_unlock(&data_sinfo->lock);
3124 * called when we are clearing an delalloc extent from the
3125 * inode's io_tree or there was an error for whatever reason
3126 * after calling btrfs_check_data_free_space
3128 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3130 struct btrfs_root *root = BTRFS_I(inode)->root;
3131 struct btrfs_space_info *data_sinfo;
3133 /* make sure bytes are sectorsize aligned */
3134 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3136 data_sinfo = BTRFS_I(inode)->space_info;
3137 spin_lock(&data_sinfo->lock);
3138 data_sinfo->bytes_may_use -= bytes;
3139 BTRFS_I(inode)->reserved_bytes -= bytes;
3140 spin_unlock(&data_sinfo->lock);
3143 static void force_metadata_allocation(struct btrfs_fs_info *info)
3145 struct list_head *head = &info->space_info;
3146 struct btrfs_space_info *found;
3149 list_for_each_entry_rcu(found, head, list) {
3150 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3151 found->force_alloc = CHUNK_ALLOC_FORCE;
3156 static int should_alloc_chunk(struct btrfs_root *root,
3157 struct btrfs_space_info *sinfo, u64 alloc_bytes,
3160 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3161 u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
3164 if (force == CHUNK_ALLOC_FORCE)
3168 * in limited mode, we want to have some free space up to
3169 * about 1% of the FS size.
3171 if (force == CHUNK_ALLOC_LIMITED) {
3172 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3173 thresh = max_t(u64, 64 * 1024 * 1024,
3174 div_factor_fine(thresh, 1));
3176 if (num_bytes - num_allocated < thresh)
3181 * we have two similar checks here, one based on percentage
3182 * and once based on a hard number of 256MB. The idea
3183 * is that if we have a good amount of free
3184 * room, don't allocate a chunk. A good mount is
3185 * less than 80% utilized of the chunks we have allocated,
3186 * or more than 256MB free
3188 if (num_allocated + alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3191 if (num_allocated + alloc_bytes < div_factor(num_bytes, 8))
3194 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3196 /* 256MB or 5% of the FS */
3197 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3199 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3204 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3205 struct btrfs_root *extent_root, u64 alloc_bytes,
3206 u64 flags, int force)
3208 struct btrfs_space_info *space_info;
3209 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3210 int wait_for_alloc = 0;
3213 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3215 space_info = __find_space_info(extent_root->fs_info, flags);
3217 ret = update_space_info(extent_root->fs_info, flags,
3221 BUG_ON(!space_info);
3224 spin_lock(&space_info->lock);
3225 if (space_info->force_alloc)
3226 force = space_info->force_alloc;
3227 if (space_info->full) {
3228 spin_unlock(&space_info->lock);
3232 if (!should_alloc_chunk(extent_root, space_info, alloc_bytes, force)) {
3233 spin_unlock(&space_info->lock);
3235 } else if (space_info->chunk_alloc) {
3238 space_info->chunk_alloc = 1;
3241 spin_unlock(&space_info->lock);
3243 mutex_lock(&fs_info->chunk_mutex);
3246 * The chunk_mutex is held throughout the entirety of a chunk
3247 * allocation, so once we've acquired the chunk_mutex we know that the
3248 * other guy is done and we need to recheck and see if we should
3251 if (wait_for_alloc) {
3252 mutex_unlock(&fs_info->chunk_mutex);
3258 * If we have mixed data/metadata chunks we want to make sure we keep
3259 * allocating mixed chunks instead of individual chunks.
3261 if (btrfs_mixed_space_info(space_info))
3262 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3265 * if we're doing a data chunk, go ahead and make sure that
3266 * we keep a reasonable number of metadata chunks allocated in the
3269 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3270 fs_info->data_chunk_allocations++;
3271 if (!(fs_info->data_chunk_allocations %
3272 fs_info->metadata_ratio))
3273 force_metadata_allocation(fs_info);
3276 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3277 if (ret < 0 && ret != -ENOSPC)
3280 spin_lock(&space_info->lock);
3282 space_info->full = 1;
3286 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3287 space_info->chunk_alloc = 0;
3288 spin_unlock(&space_info->lock);
3290 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3295 * shrink metadata reservation for delalloc
3297 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3298 struct btrfs_root *root, u64 to_reclaim, int sync)
3300 struct btrfs_block_rsv *block_rsv;
3301 struct btrfs_space_info *space_info;
3306 int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3308 unsigned long progress;
3310 block_rsv = &root->fs_info->delalloc_block_rsv;
3311 space_info = block_rsv->space_info;
3314 reserved = space_info->bytes_reserved;
3315 progress = space_info->reservation_progress;
3321 if (root->fs_info->delalloc_bytes == 0) {
3324 btrfs_wait_ordered_extents(root, 0, 0);
3328 max_reclaim = min(reserved, to_reclaim);
3330 while (loops < 1024) {
3331 /* have the flusher threads jump in and do some IO */
3333 nr_pages = min_t(unsigned long, nr_pages,
3334 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3335 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3337 spin_lock(&space_info->lock);
3338 if (reserved > space_info->bytes_reserved)
3339 reclaimed += reserved - space_info->bytes_reserved;
3340 reserved = space_info->bytes_reserved;
3341 spin_unlock(&space_info->lock);
3345 if (reserved == 0 || reclaimed >= max_reclaim)
3348 if (trans && trans->transaction->blocked)
3351 time_left = schedule_timeout_interruptible(1);
3353 /* We were interrupted, exit */
3357 /* we've kicked the IO a few times, if anything has been freed,
3358 * exit. There is no sense in looping here for a long time
3359 * when we really need to commit the transaction, or there are
3360 * just too many writers without enough free space
3365 if (progress != space_info->reservation_progress)
3370 if (reclaimed >= to_reclaim && !trans)
3371 btrfs_wait_ordered_extents(root, 0, 0);
3372 return reclaimed >= to_reclaim;
3376 * Retries tells us how many times we've called reserve_metadata_bytes. The
3377 * idea is if this is the first call (retries == 0) then we will add to our
3378 * reserved count if we can't make the allocation in order to hold our place
3379 * while we go and try and free up space. That way for retries > 1 we don't try
3380 * and add space, we just check to see if the amount of unused space is >= the
3381 * total space, meaning that our reservation is valid.
3383 * However if we don't intend to retry this reservation, pass -1 as retries so
3384 * that it short circuits this logic.
3386 static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
3387 struct btrfs_root *root,
3388 struct btrfs_block_rsv *block_rsv,
3389 u64 orig_bytes, int flush)
3391 struct btrfs_space_info *space_info = block_rsv->space_info;
3393 u64 num_bytes = orig_bytes;
3396 bool committed = false;
3397 bool flushing = false;
3401 spin_lock(&space_info->lock);
3403 * We only want to wait if somebody other than us is flushing and we are
3404 * actually alloed to flush.
3406 while (flush && !flushing && space_info->flush) {
3407 spin_unlock(&space_info->lock);
3409 * If we have a trans handle we can't wait because the flusher
3410 * may have to commit the transaction, which would mean we would
3411 * deadlock since we are waiting for the flusher to finish, but
3412 * hold the current transaction open.
3416 ret = wait_event_interruptible(space_info->wait,
3417 !space_info->flush);
3418 /* Must have been interrupted, return */
3422 spin_lock(&space_info->lock);
3426 unused = space_info->bytes_used + space_info->bytes_reserved +
3427 space_info->bytes_pinned + space_info->bytes_readonly +
3428 space_info->bytes_may_use;
3431 * The idea here is that we've not already over-reserved the block group
3432 * then we can go ahead and save our reservation first and then start
3433 * flushing if we need to. Otherwise if we've already overcommitted
3434 * lets start flushing stuff first and then come back and try to make
3437 if (unused <= space_info->total_bytes) {
3438 unused = space_info->total_bytes - unused;
3439 if (unused >= num_bytes) {
3440 space_info->bytes_reserved += orig_bytes;
3444 * Ok set num_bytes to orig_bytes since we aren't
3445 * overocmmitted, this way we only try and reclaim what
3448 num_bytes = orig_bytes;
3452 * Ok we're over committed, set num_bytes to the overcommitted
3453 * amount plus the amount of bytes that we need for this
3456 num_bytes = unused - space_info->total_bytes +
3457 (orig_bytes * (retries + 1));
3461 * Couldn't make our reservation, save our place so while we're trying
3462 * to reclaim space we can actually use it instead of somebody else
3463 * stealing it from us.
3467 space_info->flush = 1;
3470 spin_unlock(&space_info->lock);
3476 * We do synchronous shrinking since we don't actually unreserve
3477 * metadata until after the IO is completed.
3479 ret = shrink_delalloc(trans, root, num_bytes, 1);
3486 * So if we were overcommitted it's possible that somebody else flushed
3487 * out enough space and we simply didn't have enough space to reclaim,
3488 * so go back around and try again.
3496 * Not enough space to be reclaimed, don't bother committing the
3499 spin_lock(&space_info->lock);
3500 if (space_info->bytes_pinned < orig_bytes)
3502 spin_unlock(&space_info->lock);
3514 trans = btrfs_join_transaction(root);
3517 ret = btrfs_commit_transaction(trans, root);
3526 spin_lock(&space_info->lock);
3527 space_info->flush = 0;
3528 wake_up_all(&space_info->wait);
3529 spin_unlock(&space_info->lock);
3534 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3535 struct btrfs_root *root)
3537 struct btrfs_block_rsv *block_rsv;
3539 block_rsv = trans->block_rsv;
3541 block_rsv = root->block_rsv;
3544 block_rsv = &root->fs_info->empty_block_rsv;
3549 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3553 spin_lock(&block_rsv->lock);
3554 if (block_rsv->reserved >= num_bytes) {
3555 block_rsv->reserved -= num_bytes;
3556 if (block_rsv->reserved < block_rsv->size)
3557 block_rsv->full = 0;
3560 spin_unlock(&block_rsv->lock);
3564 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3565 u64 num_bytes, int update_size)
3567 spin_lock(&block_rsv->lock);
3568 block_rsv->reserved += num_bytes;
3570 block_rsv->size += num_bytes;
3571 else if (block_rsv->reserved >= block_rsv->size)
3572 block_rsv->full = 1;
3573 spin_unlock(&block_rsv->lock);
3576 static void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3577 struct btrfs_block_rsv *dest, u64 num_bytes)
3579 struct btrfs_space_info *space_info = block_rsv->space_info;
3581 spin_lock(&block_rsv->lock);
3582 if (num_bytes == (u64)-1)
3583 num_bytes = block_rsv->size;
3584 block_rsv->size -= num_bytes;
3585 if (block_rsv->reserved >= block_rsv->size) {
3586 num_bytes = block_rsv->reserved - block_rsv->size;
3587 block_rsv->reserved = block_rsv->size;
3588 block_rsv->full = 1;
3592 spin_unlock(&block_rsv->lock);
3594 if (num_bytes > 0) {
3596 spin_lock(&dest->lock);
3600 bytes_to_add = dest->size - dest->reserved;
3601 bytes_to_add = min(num_bytes, bytes_to_add);
3602 dest->reserved += bytes_to_add;
3603 if (dest->reserved >= dest->size)
3605 num_bytes -= bytes_to_add;
3607 spin_unlock(&dest->lock);
3610 spin_lock(&space_info->lock);
3611 space_info->bytes_reserved -= num_bytes;
3612 space_info->reservation_progress++;
3613 spin_unlock(&space_info->lock);
3618 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3619 struct btrfs_block_rsv *dst, u64 num_bytes)
3623 ret = block_rsv_use_bytes(src, num_bytes);
3627 block_rsv_add_bytes(dst, num_bytes, 1);
3631 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3633 memset(rsv, 0, sizeof(*rsv));
3634 spin_lock_init(&rsv->lock);
3635 atomic_set(&rsv->usage, 1);
3637 INIT_LIST_HEAD(&rsv->list);
3640 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3642 struct btrfs_block_rsv *block_rsv;
3643 struct btrfs_fs_info *fs_info = root->fs_info;
3645 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3649 btrfs_init_block_rsv(block_rsv);
3650 block_rsv->space_info = __find_space_info(fs_info,
3651 BTRFS_BLOCK_GROUP_METADATA);
3655 void btrfs_free_block_rsv(struct btrfs_root *root,
3656 struct btrfs_block_rsv *rsv)
3658 if (rsv && atomic_dec_and_test(&rsv->usage)) {
3659 btrfs_block_rsv_release(root, rsv, (u64)-1);
3666 * make the block_rsv struct be able to capture freed space.
3667 * the captured space will re-add to the the block_rsv struct
3668 * after transaction commit
3670 void btrfs_add_durable_block_rsv(struct btrfs_fs_info *fs_info,
3671 struct btrfs_block_rsv *block_rsv)
3673 block_rsv->durable = 1;
3674 mutex_lock(&fs_info->durable_block_rsv_mutex);
3675 list_add_tail(&block_rsv->list, &fs_info->durable_block_rsv_list);
3676 mutex_unlock(&fs_info->durable_block_rsv_mutex);
3679 int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
3680 struct btrfs_root *root,
3681 struct btrfs_block_rsv *block_rsv,
3689 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
3691 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3698 int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
3699 struct btrfs_root *root,
3700 struct btrfs_block_rsv *block_rsv,
3701 u64 min_reserved, int min_factor)
3704 int commit_trans = 0;
3710 spin_lock(&block_rsv->lock);
3712 num_bytes = div_factor(block_rsv->size, min_factor);
3713 if (min_reserved > num_bytes)
3714 num_bytes = min_reserved;
3716 if (block_rsv->reserved >= num_bytes) {
3719 num_bytes -= block_rsv->reserved;
3720 if (block_rsv->durable &&
3721 block_rsv->freed[0] + block_rsv->freed[1] >= num_bytes)
3724 spin_unlock(&block_rsv->lock);
3728 if (block_rsv->refill_used) {
3729 ret = reserve_metadata_bytes(trans, root, block_rsv,
3732 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3740 trans = btrfs_join_transaction(root);
3741 BUG_ON(IS_ERR(trans));
3742 ret = btrfs_commit_transaction(trans, root);
3749 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3750 struct btrfs_block_rsv *dst_rsv,
3753 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3756 void btrfs_block_rsv_release(struct btrfs_root *root,
3757 struct btrfs_block_rsv *block_rsv,
3760 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3761 if (global_rsv->full || global_rsv == block_rsv ||
3762 block_rsv->space_info != global_rsv->space_info)
3764 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3768 * helper to calculate size of global block reservation.
3769 * the desired value is sum of space used by extent tree,
3770 * checksum tree and root tree
3772 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3774 struct btrfs_space_info *sinfo;
3778 int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
3780 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3781 spin_lock(&sinfo->lock);
3782 data_used = sinfo->bytes_used;
3783 spin_unlock(&sinfo->lock);
3785 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3786 spin_lock(&sinfo->lock);
3787 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3789 meta_used = sinfo->bytes_used;
3790 spin_unlock(&sinfo->lock);
3792 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3794 num_bytes += div64_u64(data_used + meta_used, 50);
3796 if (num_bytes * 3 > meta_used)
3797 num_bytes = div64_u64(meta_used, 3);
3799 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3802 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3804 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3805 struct btrfs_space_info *sinfo = block_rsv->space_info;
3808 num_bytes = calc_global_metadata_size(fs_info);
3810 spin_lock(&block_rsv->lock);
3811 spin_lock(&sinfo->lock);
3813 block_rsv->size = num_bytes;
3815 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3816 sinfo->bytes_reserved + sinfo->bytes_readonly +
3817 sinfo->bytes_may_use;
3819 if (sinfo->total_bytes > num_bytes) {
3820 num_bytes = sinfo->total_bytes - num_bytes;
3821 block_rsv->reserved += num_bytes;
3822 sinfo->bytes_reserved += num_bytes;
3825 if (block_rsv->reserved >= block_rsv->size) {
3826 num_bytes = block_rsv->reserved - block_rsv->size;
3827 sinfo->bytes_reserved -= num_bytes;
3828 sinfo->reservation_progress++;
3829 block_rsv->reserved = block_rsv->size;
3830 block_rsv->full = 1;
3833 spin_unlock(&sinfo->lock);
3834 spin_unlock(&block_rsv->lock);
3837 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3839 struct btrfs_space_info *space_info;
3841 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3842 fs_info->chunk_block_rsv.space_info = space_info;
3843 fs_info->chunk_block_rsv.priority = 10;
3845 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3846 fs_info->global_block_rsv.space_info = space_info;
3847 fs_info->global_block_rsv.priority = 10;
3848 fs_info->global_block_rsv.refill_used = 1;
3849 fs_info->delalloc_block_rsv.space_info = space_info;
3850 fs_info->trans_block_rsv.space_info = space_info;
3851 fs_info->empty_block_rsv.space_info = space_info;
3852 fs_info->empty_block_rsv.priority = 10;
3854 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3855 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3856 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3857 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3858 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3860 btrfs_add_durable_block_rsv(fs_info, &fs_info->global_block_rsv);
3862 btrfs_add_durable_block_rsv(fs_info, &fs_info->delalloc_block_rsv);
3864 update_global_block_rsv(fs_info);
3867 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3869 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3870 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3871 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3872 WARN_ON(fs_info->trans_block_rsv.size > 0);
3873 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3874 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3875 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3878 int btrfs_truncate_reserve_metadata(struct btrfs_trans_handle *trans,
3879 struct btrfs_root *root,
3880 struct btrfs_block_rsv *rsv)
3882 struct btrfs_block_rsv *trans_rsv = &root->fs_info->trans_block_rsv;
3887 * Truncate should be freeing data, but give us 2 items just in case it
3888 * needs to use some space. We may want to be smarter about this in the
3891 num_bytes = btrfs_calc_trans_metadata_size(root, 2);
3893 /* We already have enough bytes, just return */
3894 if (rsv->reserved >= num_bytes)
3897 num_bytes -= rsv->reserved;
3900 * You should have reserved enough space before hand to do this, so this
3903 ret = block_rsv_migrate_bytes(trans_rsv, rsv, num_bytes);
3909 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3910 struct btrfs_root *root)
3912 if (!trans->bytes_reserved)
3915 BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv);
3916 btrfs_block_rsv_release(root, trans->block_rsv,
3917 trans->bytes_reserved);
3918 trans->bytes_reserved = 0;
3921 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3922 struct inode *inode)
3924 struct btrfs_root *root = BTRFS_I(inode)->root;
3925 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3926 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3929 * We need to hold space in order to delete our orphan item once we've
3930 * added it, so this takes the reservation so we can release it later
3931 * when we are truly done with the orphan item.
3933 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
3934 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3937 void btrfs_orphan_release_metadata(struct inode *inode)
3939 struct btrfs_root *root = BTRFS_I(inode)->root;
3940 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
3941 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3944 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3945 struct btrfs_pending_snapshot *pending)
3947 struct btrfs_root *root = pending->root;
3948 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3949 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3951 * two for root back/forward refs, two for directory entries
3952 * and one for root of the snapshot.
3954 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 5);
3955 dst_rsv->space_info = src_rsv->space_info;
3956 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3959 static unsigned drop_outstanding_extent(struct inode *inode)
3961 unsigned dropped_extents = 0;
3963 spin_lock(&BTRFS_I(inode)->lock);
3964 BUG_ON(!BTRFS_I(inode)->outstanding_extents);
3965 BTRFS_I(inode)->outstanding_extents--;
3968 * If we have more or the same amount of outsanding extents than we have
3969 * reserved then we need to leave the reserved extents count alone.
3971 if (BTRFS_I(inode)->outstanding_extents >=
3972 BTRFS_I(inode)->reserved_extents)
3975 dropped_extents = BTRFS_I(inode)->reserved_extents -
3976 BTRFS_I(inode)->outstanding_extents;
3977 BTRFS_I(inode)->reserved_extents -= dropped_extents;
3979 spin_unlock(&BTRFS_I(inode)->lock);
3980 return dropped_extents;
3983 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
3985 return num_bytes >>= 3;
3988 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
3990 struct btrfs_root *root = BTRFS_I(inode)->root;
3991 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
3993 unsigned nr_extents = 0;
3996 if (btrfs_transaction_in_commit(root->fs_info))
3997 schedule_timeout(1);
3999 num_bytes = ALIGN(num_bytes, root->sectorsize);
4001 spin_lock(&BTRFS_I(inode)->lock);
4002 BTRFS_I(inode)->outstanding_extents++;
4004 if (BTRFS_I(inode)->outstanding_extents >
4005 BTRFS_I(inode)->reserved_extents) {
4006 nr_extents = BTRFS_I(inode)->outstanding_extents -
4007 BTRFS_I(inode)->reserved_extents;
4008 BTRFS_I(inode)->reserved_extents += nr_extents;
4010 to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
4012 spin_unlock(&BTRFS_I(inode)->lock);
4014 to_reserve += calc_csum_metadata_size(inode, num_bytes);
4015 ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
4019 * We don't need the return value since our reservation failed,
4020 * we just need to clean up our counter.
4022 dropped = drop_outstanding_extent(inode);
4023 WARN_ON(dropped > 1);
4027 block_rsv_add_bytes(block_rsv, to_reserve, 1);
4032 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4034 struct btrfs_root *root = BTRFS_I(inode)->root;
4038 num_bytes = ALIGN(num_bytes, root->sectorsize);
4039 dropped = drop_outstanding_extent(inode);
4041 to_free = calc_csum_metadata_size(inode, num_bytes);
4043 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4045 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4049 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4053 ret = btrfs_check_data_free_space(inode, num_bytes);
4057 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4059 btrfs_free_reserved_data_space(inode, num_bytes);
4066 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4068 btrfs_delalloc_release_metadata(inode, num_bytes);
4069 btrfs_free_reserved_data_space(inode, num_bytes);
4072 static int update_block_group(struct btrfs_trans_handle *trans,
4073 struct btrfs_root *root,
4074 u64 bytenr, u64 num_bytes, int alloc)
4076 struct btrfs_block_group_cache *cache = NULL;
4077 struct btrfs_fs_info *info = root->fs_info;
4078 u64 total = num_bytes;
4083 /* block accounting for super block */
4084 spin_lock(&info->delalloc_lock);
4085 old_val = btrfs_super_bytes_used(&info->super_copy);
4087 old_val += num_bytes;
4089 old_val -= num_bytes;
4090 btrfs_set_super_bytes_used(&info->super_copy, old_val);
4091 spin_unlock(&info->delalloc_lock);
4094 cache = btrfs_lookup_block_group(info, bytenr);
4097 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4098 BTRFS_BLOCK_GROUP_RAID1 |
4099 BTRFS_BLOCK_GROUP_RAID10))
4104 * If this block group has free space cache written out, we
4105 * need to make sure to load it if we are removing space. This
4106 * is because we need the unpinning stage to actually add the
4107 * space back to the block group, otherwise we will leak space.
4109 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4110 cache_block_group(cache, trans, NULL, 1);
4112 byte_in_group = bytenr - cache->key.objectid;
4113 WARN_ON(byte_in_group > cache->key.offset);
4115 spin_lock(&cache->space_info->lock);
4116 spin_lock(&cache->lock);
4118 if (btrfs_super_cache_generation(&info->super_copy) != 0 &&
4119 cache->disk_cache_state < BTRFS_DC_CLEAR)
4120 cache->disk_cache_state = BTRFS_DC_CLEAR;
4123 old_val = btrfs_block_group_used(&cache->item);
4124 num_bytes = min(total, cache->key.offset - byte_in_group);
4126 old_val += num_bytes;
4127 btrfs_set_block_group_used(&cache->item, old_val);
4128 cache->reserved -= num_bytes;
4129 cache->space_info->bytes_reserved -= num_bytes;
4130 cache->space_info->reservation_progress++;
4131 cache->space_info->bytes_used += num_bytes;
4132 cache->space_info->disk_used += num_bytes * factor;
4133 spin_unlock(&cache->lock);
4134 spin_unlock(&cache->space_info->lock);
4136 old_val -= num_bytes;
4137 btrfs_set_block_group_used(&cache->item, old_val);
4138 cache->pinned += num_bytes;
4139 cache->space_info->bytes_pinned += num_bytes;
4140 cache->space_info->bytes_used -= num_bytes;
4141 cache->space_info->disk_used -= num_bytes * factor;
4142 spin_unlock(&cache->lock);
4143 spin_unlock(&cache->space_info->lock);
4145 set_extent_dirty(info->pinned_extents,
4146 bytenr, bytenr + num_bytes - 1,
4147 GFP_NOFS | __GFP_NOFAIL);
4149 btrfs_put_block_group(cache);
4151 bytenr += num_bytes;
4156 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4158 struct btrfs_block_group_cache *cache;
4161 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4165 bytenr = cache->key.objectid;
4166 btrfs_put_block_group(cache);
4171 static int pin_down_extent(struct btrfs_root *root,
4172 struct btrfs_block_group_cache *cache,
4173 u64 bytenr, u64 num_bytes, int reserved)
4175 spin_lock(&cache->space_info->lock);
4176 spin_lock(&cache->lock);
4177 cache->pinned += num_bytes;
4178 cache->space_info->bytes_pinned += num_bytes;
4180 cache->reserved -= num_bytes;
4181 cache->space_info->bytes_reserved -= num_bytes;
4182 cache->space_info->reservation_progress++;
4184 spin_unlock(&cache->lock);
4185 spin_unlock(&cache->space_info->lock);
4187 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4188 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4193 * this function must be called within transaction
4195 int btrfs_pin_extent(struct btrfs_root *root,
4196 u64 bytenr, u64 num_bytes, int reserved)
4198 struct btrfs_block_group_cache *cache;
4200 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4203 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4205 btrfs_put_block_group(cache);
4210 * update size of reserved extents. this function may return -EAGAIN
4211 * if 'reserve' is true or 'sinfo' is false.
4213 int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
4214 u64 num_bytes, int reserve, int sinfo)
4218 struct btrfs_space_info *space_info = cache->space_info;
4219 spin_lock(&space_info->lock);
4220 spin_lock(&cache->lock);
4225 cache->reserved += num_bytes;
4226 space_info->bytes_reserved += num_bytes;
4230 space_info->bytes_readonly += num_bytes;
4231 cache->reserved -= num_bytes;
4232 space_info->bytes_reserved -= num_bytes;
4233 space_info->reservation_progress++;
4235 spin_unlock(&cache->lock);
4236 spin_unlock(&space_info->lock);
4238 spin_lock(&cache->lock);
4243 cache->reserved += num_bytes;
4245 cache->reserved -= num_bytes;
4247 spin_unlock(&cache->lock);
4252 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4253 struct btrfs_root *root)
4255 struct btrfs_fs_info *fs_info = root->fs_info;
4256 struct btrfs_caching_control *next;
4257 struct btrfs_caching_control *caching_ctl;
4258 struct btrfs_block_group_cache *cache;
4260 down_write(&fs_info->extent_commit_sem);
4262 list_for_each_entry_safe(caching_ctl, next,
4263 &fs_info->caching_block_groups, list) {
4264 cache = caching_ctl->block_group;
4265 if (block_group_cache_done(cache)) {
4266 cache->last_byte_to_unpin = (u64)-1;
4267 list_del_init(&caching_ctl->list);
4268 put_caching_control(caching_ctl);
4270 cache->last_byte_to_unpin = caching_ctl->progress;
4274 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4275 fs_info->pinned_extents = &fs_info->freed_extents[1];
4277 fs_info->pinned_extents = &fs_info->freed_extents[0];
4279 up_write(&fs_info->extent_commit_sem);
4281 update_global_block_rsv(fs_info);
4285 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4287 struct btrfs_fs_info *fs_info = root->fs_info;
4288 struct btrfs_block_group_cache *cache = NULL;
4291 while (start <= end) {
4293 start >= cache->key.objectid + cache->key.offset) {
4295 btrfs_put_block_group(cache);
4296 cache = btrfs_lookup_block_group(fs_info, start);
4300 len = cache->key.objectid + cache->key.offset - start;
4301 len = min(len, end + 1 - start);
4303 if (start < cache->last_byte_to_unpin) {
4304 len = min(len, cache->last_byte_to_unpin - start);
4305 btrfs_add_free_space(cache, start, len);
4310 spin_lock(&cache->space_info->lock);
4311 spin_lock(&cache->lock);
4312 cache->pinned -= len;
4313 cache->space_info->bytes_pinned -= len;
4315 cache->space_info->bytes_readonly += len;
4316 } else if (cache->reserved_pinned > 0) {
4317 len = min(len, cache->reserved_pinned);
4318 cache->reserved_pinned -= len;
4319 cache->space_info->bytes_reserved += len;
4321 spin_unlock(&cache->lock);
4322 spin_unlock(&cache->space_info->lock);
4326 btrfs_put_block_group(cache);
4330 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4331 struct btrfs_root *root)
4333 struct btrfs_fs_info *fs_info = root->fs_info;
4334 struct extent_io_tree *unpin;
4335 struct btrfs_block_rsv *block_rsv;
4336 struct btrfs_block_rsv *next_rsv;
4342 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4343 unpin = &fs_info->freed_extents[1];
4345 unpin = &fs_info->freed_extents[0];
4348 ret = find_first_extent_bit(unpin, 0, &start, &end,
4353 if (btrfs_test_opt(root, DISCARD))
4354 ret = btrfs_discard_extent(root, start,
4355 end + 1 - start, NULL);
4357 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4358 unpin_extent_range(root, start, end);
4362 mutex_lock(&fs_info->durable_block_rsv_mutex);
4363 list_for_each_entry_safe(block_rsv, next_rsv,
4364 &fs_info->durable_block_rsv_list, list) {
4366 idx = trans->transid & 0x1;
4367 if (block_rsv->freed[idx] > 0) {
4368 block_rsv_add_bytes(block_rsv,
4369 block_rsv->freed[idx], 0);
4370 block_rsv->freed[idx] = 0;
4372 if (atomic_read(&block_rsv->usage) == 0) {
4373 btrfs_block_rsv_release(root, block_rsv, (u64)-1);
4375 if (block_rsv->freed[0] == 0 &&
4376 block_rsv->freed[1] == 0) {
4377 list_del_init(&block_rsv->list);
4381 btrfs_block_rsv_release(root, block_rsv, 0);
4384 mutex_unlock(&fs_info->durable_block_rsv_mutex);
4389 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4390 struct btrfs_root *root,
4391 u64 bytenr, u64 num_bytes, u64 parent,
4392 u64 root_objectid, u64 owner_objectid,
4393 u64 owner_offset, int refs_to_drop,
4394 struct btrfs_delayed_extent_op *extent_op)
4396 struct btrfs_key key;
4397 struct btrfs_path *path;
4398 struct btrfs_fs_info *info = root->fs_info;
4399 struct btrfs_root *extent_root = info->extent_root;
4400 struct extent_buffer *leaf;
4401 struct btrfs_extent_item *ei;
4402 struct btrfs_extent_inline_ref *iref;
4405 int extent_slot = 0;
4406 int found_extent = 0;
4411 path = btrfs_alloc_path();
4416 path->leave_spinning = 1;
4418 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4419 BUG_ON(!is_data && refs_to_drop != 1);
4421 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4422 bytenr, num_bytes, parent,
4423 root_objectid, owner_objectid,
4426 extent_slot = path->slots[0];
4427 while (extent_slot >= 0) {
4428 btrfs_item_key_to_cpu(path->nodes[0], &key,
4430 if (key.objectid != bytenr)
4432 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4433 key.offset == num_bytes) {
4437 if (path->slots[0] - extent_slot > 5)
4441 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4442 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4443 if (found_extent && item_size < sizeof(*ei))
4446 if (!found_extent) {
4448 ret = remove_extent_backref(trans, extent_root, path,
4452 btrfs_release_path(path);
4453 path->leave_spinning = 1;
4455 key.objectid = bytenr;
4456 key.type = BTRFS_EXTENT_ITEM_KEY;
4457 key.offset = num_bytes;
4459 ret = btrfs_search_slot(trans, extent_root,
4462 printk(KERN_ERR "umm, got %d back from search"
4463 ", was looking for %llu\n", ret,
4464 (unsigned long long)bytenr);
4466 btrfs_print_leaf(extent_root,
4470 extent_slot = path->slots[0];
4473 btrfs_print_leaf(extent_root, path->nodes[0]);
4475 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4476 "parent %llu root %llu owner %llu offset %llu\n",
4477 (unsigned long long)bytenr,
4478 (unsigned long long)parent,
4479 (unsigned long long)root_objectid,
4480 (unsigned long long)owner_objectid,
4481 (unsigned long long)owner_offset);
4484 leaf = path->nodes[0];
4485 item_size = btrfs_item_size_nr(leaf, extent_slot);
4486 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4487 if (item_size < sizeof(*ei)) {
4488 BUG_ON(found_extent || extent_slot != path->slots[0]);
4489 ret = convert_extent_item_v0(trans, extent_root, path,
4493 btrfs_release_path(path);
4494 path->leave_spinning = 1;
4496 key.objectid = bytenr;
4497 key.type = BTRFS_EXTENT_ITEM_KEY;
4498 key.offset = num_bytes;
4500 ret = btrfs_search_slot(trans, extent_root, &key, path,
4503 printk(KERN_ERR "umm, got %d back from search"
4504 ", was looking for %llu\n", ret,
4505 (unsigned long long)bytenr);
4506 btrfs_print_leaf(extent_root, path->nodes[0]);
4509 extent_slot = path->slots[0];
4510 leaf = path->nodes[0];
4511 item_size = btrfs_item_size_nr(leaf, extent_slot);
4514 BUG_ON(item_size < sizeof(*ei));
4515 ei = btrfs_item_ptr(leaf, extent_slot,
4516 struct btrfs_extent_item);
4517 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4518 struct btrfs_tree_block_info *bi;
4519 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4520 bi = (struct btrfs_tree_block_info *)(ei + 1);
4521 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4524 refs = btrfs_extent_refs(leaf, ei);
4525 BUG_ON(refs < refs_to_drop);
4526 refs -= refs_to_drop;
4530 __run_delayed_extent_op(extent_op, leaf, ei);
4532 * In the case of inline back ref, reference count will
4533 * be updated by remove_extent_backref
4536 BUG_ON(!found_extent);
4538 btrfs_set_extent_refs(leaf, ei, refs);
4539 btrfs_mark_buffer_dirty(leaf);
4542 ret = remove_extent_backref(trans, extent_root, path,
4549 BUG_ON(is_data && refs_to_drop !=
4550 extent_data_ref_count(root, path, iref));
4552 BUG_ON(path->slots[0] != extent_slot);
4554 BUG_ON(path->slots[0] != extent_slot + 1);
4555 path->slots[0] = extent_slot;
4560 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4563 btrfs_release_path(path);
4566 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4569 invalidate_mapping_pages(info->btree_inode->i_mapping,
4570 bytenr >> PAGE_CACHE_SHIFT,
4571 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4574 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4577 btrfs_free_path(path);
4582 * when we free an block, it is possible (and likely) that we free the last
4583 * delayed ref for that extent as well. This searches the delayed ref tree for
4584 * a given extent, and if there are no other delayed refs to be processed, it
4585 * removes it from the tree.
4587 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4588 struct btrfs_root *root, u64 bytenr)
4590 struct btrfs_delayed_ref_head *head;
4591 struct btrfs_delayed_ref_root *delayed_refs;
4592 struct btrfs_delayed_ref_node *ref;
4593 struct rb_node *node;
4596 delayed_refs = &trans->transaction->delayed_refs;
4597 spin_lock(&delayed_refs->lock);
4598 head = btrfs_find_delayed_ref_head(trans, bytenr);
4602 node = rb_prev(&head->node.rb_node);
4606 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4608 /* there are still entries for this ref, we can't drop it */
4609 if (ref->bytenr == bytenr)
4612 if (head->extent_op) {
4613 if (!head->must_insert_reserved)
4615 kfree(head->extent_op);
4616 head->extent_op = NULL;
4620 * waiting for the lock here would deadlock. If someone else has it
4621 * locked they are already in the process of dropping it anyway
4623 if (!mutex_trylock(&head->mutex))
4627 * at this point we have a head with no other entries. Go
4628 * ahead and process it.
4630 head->node.in_tree = 0;
4631 rb_erase(&head->node.rb_node, &delayed_refs->root);
4633 delayed_refs->num_entries--;
4636 * we don't take a ref on the node because we're removing it from the
4637 * tree, so we just steal the ref the tree was holding.
4639 delayed_refs->num_heads--;
4640 if (list_empty(&head->cluster))
4641 delayed_refs->num_heads_ready--;
4643 list_del_init(&head->cluster);
4644 spin_unlock(&delayed_refs->lock);
4646 BUG_ON(head->extent_op);
4647 if (head->must_insert_reserved)
4650 mutex_unlock(&head->mutex);
4651 btrfs_put_delayed_ref(&head->node);
4654 spin_unlock(&delayed_refs->lock);
4658 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4659 struct btrfs_root *root,
4660 struct extent_buffer *buf,
4661 u64 parent, int last_ref)
4663 struct btrfs_block_rsv *block_rsv;
4664 struct btrfs_block_group_cache *cache = NULL;
4667 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4668 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4669 parent, root->root_key.objectid,
4670 btrfs_header_level(buf),
4671 BTRFS_DROP_DELAYED_REF, NULL);
4678 block_rsv = get_block_rsv(trans, root);
4679 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4680 if (block_rsv->space_info != cache->space_info)
4683 if (btrfs_header_generation(buf) == trans->transid) {
4684 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4685 ret = check_ref_cleanup(trans, root, buf->start);
4690 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4691 pin_down_extent(root, cache, buf->start, buf->len, 1);
4695 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4697 btrfs_add_free_space(cache, buf->start, buf->len);
4698 ret = btrfs_update_reserved_bytes(cache, buf->len, 0, 0);
4699 if (ret == -EAGAIN) {
4700 /* block group became read-only */
4701 btrfs_update_reserved_bytes(cache, buf->len, 0, 1);
4706 spin_lock(&block_rsv->lock);
4707 if (block_rsv->reserved < block_rsv->size) {
4708 block_rsv->reserved += buf->len;
4711 spin_unlock(&block_rsv->lock);
4714 spin_lock(&cache->space_info->lock);
4715 cache->space_info->bytes_reserved -= buf->len;
4716 cache->space_info->reservation_progress++;
4717 spin_unlock(&cache->space_info->lock);
4722 if (block_rsv->durable && !cache->ro) {
4724 spin_lock(&cache->lock);
4726 cache->reserved_pinned += buf->len;
4729 spin_unlock(&cache->lock);
4732 spin_lock(&block_rsv->lock);
4733 block_rsv->freed[trans->transid & 0x1] += buf->len;
4734 spin_unlock(&block_rsv->lock);
4739 * Deleting the buffer, clear the corrupt flag since it doesn't matter
4742 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
4743 btrfs_put_block_group(cache);
4746 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4747 struct btrfs_root *root,
4748 u64 bytenr, u64 num_bytes, u64 parent,
4749 u64 root_objectid, u64 owner, u64 offset)
4754 * tree log blocks never actually go into the extent allocation
4755 * tree, just update pinning info and exit early.
4757 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4758 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4759 /* unlocks the pinned mutex */
4760 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4762 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4763 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4764 parent, root_objectid, (int)owner,
4765 BTRFS_DROP_DELAYED_REF, NULL);
4768 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4769 parent, root_objectid, owner,
4770 offset, BTRFS_DROP_DELAYED_REF, NULL);
4776 static u64 stripe_align(struct btrfs_root *root, u64 val)
4778 u64 mask = ((u64)root->stripesize - 1);
4779 u64 ret = (val + mask) & ~mask;
4784 * when we wait for progress in the block group caching, its because
4785 * our allocation attempt failed at least once. So, we must sleep
4786 * and let some progress happen before we try again.
4788 * This function will sleep at least once waiting for new free space to
4789 * show up, and then it will check the block group free space numbers
4790 * for our min num_bytes. Another option is to have it go ahead
4791 * and look in the rbtree for a free extent of a given size, but this
4795 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4798 struct btrfs_caching_control *caching_ctl;
4801 caching_ctl = get_caching_control(cache);
4805 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4806 (cache->free_space_ctl->free_space >= num_bytes));
4808 put_caching_control(caching_ctl);
4813 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4815 struct btrfs_caching_control *caching_ctl;
4818 caching_ctl = get_caching_control(cache);
4822 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4824 put_caching_control(caching_ctl);
4828 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4831 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4833 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4835 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4837 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4844 enum btrfs_loop_type {
4845 LOOP_FIND_IDEAL = 0,
4846 LOOP_CACHING_NOWAIT = 1,
4847 LOOP_CACHING_WAIT = 2,
4848 LOOP_ALLOC_CHUNK = 3,
4849 LOOP_NO_EMPTY_SIZE = 4,
4853 * walks the btree of allocated extents and find a hole of a given size.
4854 * The key ins is changed to record the hole:
4855 * ins->objectid == block start
4856 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4857 * ins->offset == number of blocks
4858 * Any available blocks before search_start are skipped.
4860 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4861 struct btrfs_root *orig_root,
4862 u64 num_bytes, u64 empty_size,
4863 u64 search_start, u64 search_end,
4864 u64 hint_byte, struct btrfs_key *ins,
4868 struct btrfs_root *root = orig_root->fs_info->extent_root;
4869 struct btrfs_free_cluster *last_ptr = NULL;
4870 struct btrfs_block_group_cache *block_group = NULL;
4871 int empty_cluster = 2 * 1024 * 1024;
4872 int allowed_chunk_alloc = 0;
4873 int done_chunk_alloc = 0;
4874 struct btrfs_space_info *space_info;
4875 int last_ptr_loop = 0;
4878 bool found_uncached_bg = false;
4879 bool failed_cluster_refill = false;
4880 bool failed_alloc = false;
4881 bool use_cluster = true;
4882 u64 ideal_cache_percent = 0;
4883 u64 ideal_cache_offset = 0;
4885 WARN_ON(num_bytes < root->sectorsize);
4886 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4890 space_info = __find_space_info(root->fs_info, data);
4892 printk(KERN_ERR "No space info for %llu\n", data);
4897 * If the space info is for both data and metadata it means we have a
4898 * small filesystem and we can't use the clustering stuff.
4900 if (btrfs_mixed_space_info(space_info))
4901 use_cluster = false;
4903 if (orig_root->ref_cows || empty_size)
4904 allowed_chunk_alloc = 1;
4906 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
4907 last_ptr = &root->fs_info->meta_alloc_cluster;
4908 if (!btrfs_test_opt(root, SSD))
4909 empty_cluster = 64 * 1024;
4912 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
4913 btrfs_test_opt(root, SSD)) {
4914 last_ptr = &root->fs_info->data_alloc_cluster;
4918 spin_lock(&last_ptr->lock);
4919 if (last_ptr->block_group)
4920 hint_byte = last_ptr->window_start;
4921 spin_unlock(&last_ptr->lock);
4924 search_start = max(search_start, first_logical_byte(root, 0));
4925 search_start = max(search_start, hint_byte);
4930 if (search_start == hint_byte) {
4932 block_group = btrfs_lookup_block_group(root->fs_info,
4935 * we don't want to use the block group if it doesn't match our
4936 * allocation bits, or if its not cached.
4938 * However if we are re-searching with an ideal block group
4939 * picked out then we don't care that the block group is cached.
4941 if (block_group && block_group_bits(block_group, data) &&
4942 (block_group->cached != BTRFS_CACHE_NO ||
4943 search_start == ideal_cache_offset)) {
4944 down_read(&space_info->groups_sem);
4945 if (list_empty(&block_group->list) ||
4948 * someone is removing this block group,
4949 * we can't jump into the have_block_group
4950 * target because our list pointers are not
4953 btrfs_put_block_group(block_group);
4954 up_read(&space_info->groups_sem);
4956 index = get_block_group_index(block_group);
4957 goto have_block_group;
4959 } else if (block_group) {
4960 btrfs_put_block_group(block_group);
4964 down_read(&space_info->groups_sem);
4965 list_for_each_entry(block_group, &space_info->block_groups[index],
4970 btrfs_get_block_group(block_group);
4971 search_start = block_group->key.objectid;
4974 * this can happen if we end up cycling through all the
4975 * raid types, but we want to make sure we only allocate
4976 * for the proper type.
4978 if (!block_group_bits(block_group, data)) {
4979 u64 extra = BTRFS_BLOCK_GROUP_DUP |
4980 BTRFS_BLOCK_GROUP_RAID1 |
4981 BTRFS_BLOCK_GROUP_RAID10;
4984 * if they asked for extra copies and this block group
4985 * doesn't provide them, bail. This does allow us to
4986 * fill raid0 from raid1.
4988 if ((data & extra) && !(block_group->flags & extra))
4993 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
4996 ret = cache_block_group(block_group, trans,
4998 if (block_group->cached == BTRFS_CACHE_FINISHED)
4999 goto have_block_group;
5001 free_percent = btrfs_block_group_used(&block_group->item);
5002 free_percent *= 100;
5003 free_percent = div64_u64(free_percent,
5004 block_group->key.offset);
5005 free_percent = 100 - free_percent;
5006 if (free_percent > ideal_cache_percent &&
5007 likely(!block_group->ro)) {
5008 ideal_cache_offset = block_group->key.objectid;
5009 ideal_cache_percent = free_percent;
5013 * The caching workers are limited to 2 threads, so we
5014 * can queue as much work as we care to.
5016 if (loop > LOOP_FIND_IDEAL) {
5017 ret = cache_block_group(block_group, trans,
5021 found_uncached_bg = true;
5024 * If loop is set for cached only, try the next block
5027 if (loop == LOOP_FIND_IDEAL)
5031 cached = block_group_cache_done(block_group);
5032 if (unlikely(!cached))
5033 found_uncached_bg = true;
5035 if (unlikely(block_group->ro))
5038 spin_lock(&block_group->free_space_ctl->tree_lock);
5040 block_group->free_space_ctl->free_space <
5041 num_bytes + empty_size) {
5042 spin_unlock(&block_group->free_space_ctl->tree_lock);
5045 spin_unlock(&block_group->free_space_ctl->tree_lock);
5048 * Ok we want to try and use the cluster allocator, so lets look
5049 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
5050 * have tried the cluster allocator plenty of times at this
5051 * point and not have found anything, so we are likely way too
5052 * fragmented for the clustering stuff to find anything, so lets
5053 * just skip it and let the allocator find whatever block it can
5056 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
5058 * the refill lock keeps out other
5059 * people trying to start a new cluster
5061 spin_lock(&last_ptr->refill_lock);
5062 if (last_ptr->block_group &&
5063 (last_ptr->block_group->ro ||
5064 !block_group_bits(last_ptr->block_group, data))) {
5066 goto refill_cluster;
5069 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5070 num_bytes, search_start);
5072 /* we have a block, we're done */
5073 spin_unlock(&last_ptr->refill_lock);
5077 spin_lock(&last_ptr->lock);
5079 * whoops, this cluster doesn't actually point to
5080 * this block group. Get a ref on the block
5081 * group is does point to and try again
5083 if (!last_ptr_loop && last_ptr->block_group &&
5084 last_ptr->block_group != block_group &&
5086 get_block_group_index(last_ptr->block_group)) {
5088 btrfs_put_block_group(block_group);
5089 block_group = last_ptr->block_group;
5090 btrfs_get_block_group(block_group);
5091 spin_unlock(&last_ptr->lock);
5092 spin_unlock(&last_ptr->refill_lock);
5095 search_start = block_group->key.objectid;
5097 * we know this block group is properly
5098 * in the list because
5099 * btrfs_remove_block_group, drops the
5100 * cluster before it removes the block
5101 * group from the list
5103 goto have_block_group;
5105 spin_unlock(&last_ptr->lock);
5108 * this cluster didn't work out, free it and
5111 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5115 /* allocate a cluster in this block group */
5116 ret = btrfs_find_space_cluster(trans, root,
5117 block_group, last_ptr,
5119 empty_cluster + empty_size);
5122 * now pull our allocation out of this
5125 offset = btrfs_alloc_from_cluster(block_group,
5126 last_ptr, num_bytes,
5129 /* we found one, proceed */
5130 spin_unlock(&last_ptr->refill_lock);
5133 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5134 && !failed_cluster_refill) {
5135 spin_unlock(&last_ptr->refill_lock);
5137 failed_cluster_refill = true;
5138 wait_block_group_cache_progress(block_group,
5139 num_bytes + empty_cluster + empty_size);
5140 goto have_block_group;
5144 * at this point we either didn't find a cluster
5145 * or we weren't able to allocate a block from our
5146 * cluster. Free the cluster we've been trying
5147 * to use, and go to the next block group
5149 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5150 spin_unlock(&last_ptr->refill_lock);
5154 offset = btrfs_find_space_for_alloc(block_group, search_start,
5155 num_bytes, empty_size);
5157 * If we didn't find a chunk, and we haven't failed on this
5158 * block group before, and this block group is in the middle of
5159 * caching and we are ok with waiting, then go ahead and wait
5160 * for progress to be made, and set failed_alloc to true.
5162 * If failed_alloc is true then we've already waited on this
5163 * block group once and should move on to the next block group.
5165 if (!offset && !failed_alloc && !cached &&
5166 loop > LOOP_CACHING_NOWAIT) {
5167 wait_block_group_cache_progress(block_group,
5168 num_bytes + empty_size);
5169 failed_alloc = true;
5170 goto have_block_group;
5171 } else if (!offset) {
5175 search_start = stripe_align(root, offset);
5176 /* move on to the next group */
5177 if (search_start + num_bytes >= search_end) {
5178 btrfs_add_free_space(block_group, offset, num_bytes);
5182 /* move on to the next group */
5183 if (search_start + num_bytes >
5184 block_group->key.objectid + block_group->key.offset) {
5185 btrfs_add_free_space(block_group, offset, num_bytes);
5189 ins->objectid = search_start;
5190 ins->offset = num_bytes;
5192 if (offset < search_start)
5193 btrfs_add_free_space(block_group, offset,
5194 search_start - offset);
5195 BUG_ON(offset > search_start);
5197 ret = btrfs_update_reserved_bytes(block_group, num_bytes, 1,
5198 (data & BTRFS_BLOCK_GROUP_DATA));
5199 if (ret == -EAGAIN) {
5200 btrfs_add_free_space(block_group, offset, num_bytes);
5204 /* we are all good, lets return */
5205 ins->objectid = search_start;
5206 ins->offset = num_bytes;
5208 if (offset < search_start)
5209 btrfs_add_free_space(block_group, offset,
5210 search_start - offset);
5211 BUG_ON(offset > search_start);
5212 btrfs_put_block_group(block_group);
5215 failed_cluster_refill = false;
5216 failed_alloc = false;
5217 BUG_ON(index != get_block_group_index(block_group));
5218 btrfs_put_block_group(block_group);
5220 up_read(&space_info->groups_sem);
5222 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5225 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5226 * for them to make caching progress. Also
5227 * determine the best possible bg to cache
5228 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5229 * caching kthreads as we move along
5230 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5231 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5232 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5235 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE) {
5237 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5238 found_uncached_bg = false;
5240 if (!ideal_cache_percent)
5244 * 1 of the following 2 things have happened so far
5246 * 1) We found an ideal block group for caching that
5247 * is mostly full and will cache quickly, so we might
5248 * as well wait for it.
5250 * 2) We searched for cached only and we didn't find
5251 * anything, and we didn't start any caching kthreads
5252 * either, so chances are we will loop through and
5253 * start a couple caching kthreads, and then come back
5254 * around and just wait for them. This will be slower
5255 * because we will have 2 caching kthreads reading at
5256 * the same time when we could have just started one
5257 * and waited for it to get far enough to give us an
5258 * allocation, so go ahead and go to the wait caching
5261 loop = LOOP_CACHING_WAIT;
5262 search_start = ideal_cache_offset;
5263 ideal_cache_percent = 0;
5265 } else if (loop == LOOP_FIND_IDEAL) {
5267 * Didn't find a uncached bg, wait on anything we find
5270 loop = LOOP_CACHING_WAIT;
5276 if (loop == LOOP_ALLOC_CHUNK) {
5277 if (allowed_chunk_alloc) {
5278 ret = do_chunk_alloc(trans, root, num_bytes +
5279 2 * 1024 * 1024, data,
5280 CHUNK_ALLOC_LIMITED);
5281 allowed_chunk_alloc = 0;
5283 done_chunk_alloc = 1;
5284 } else if (!done_chunk_alloc &&
5285 space_info->force_alloc ==
5286 CHUNK_ALLOC_NO_FORCE) {
5287 space_info->force_alloc = CHUNK_ALLOC_LIMITED;
5291 * We didn't allocate a chunk, go ahead and drop the
5292 * empty size and loop again.
5294 if (!done_chunk_alloc)
5295 loop = LOOP_NO_EMPTY_SIZE;
5298 if (loop == LOOP_NO_EMPTY_SIZE) {
5304 } else if (!ins->objectid) {
5306 } else if (ins->objectid) {
5313 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5314 int dump_block_groups)
5316 struct btrfs_block_group_cache *cache;
5319 spin_lock(&info->lock);
5320 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
5321 (unsigned long long)(info->total_bytes - info->bytes_used -
5322 info->bytes_pinned - info->bytes_reserved -
5323 info->bytes_readonly),
5324 (info->full) ? "" : "not ");
5325 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5326 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5327 (unsigned long long)info->total_bytes,
5328 (unsigned long long)info->bytes_used,
5329 (unsigned long long)info->bytes_pinned,
5330 (unsigned long long)info->bytes_reserved,
5331 (unsigned long long)info->bytes_may_use,
5332 (unsigned long long)info->bytes_readonly);
5333 spin_unlock(&info->lock);
5335 if (!dump_block_groups)
5338 down_read(&info->groups_sem);
5340 list_for_each_entry(cache, &info->block_groups[index], list) {
5341 spin_lock(&cache->lock);
5342 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5343 "%llu pinned %llu reserved\n",
5344 (unsigned long long)cache->key.objectid,
5345 (unsigned long long)cache->key.offset,
5346 (unsigned long long)btrfs_block_group_used(&cache->item),
5347 (unsigned long long)cache->pinned,
5348 (unsigned long long)cache->reserved);
5349 btrfs_dump_free_space(cache, bytes);
5350 spin_unlock(&cache->lock);
5352 if (++index < BTRFS_NR_RAID_TYPES)
5354 up_read(&info->groups_sem);
5357 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5358 struct btrfs_root *root,
5359 u64 num_bytes, u64 min_alloc_size,
5360 u64 empty_size, u64 hint_byte,
5361 u64 search_end, struct btrfs_key *ins,
5365 u64 search_start = 0;
5367 data = btrfs_get_alloc_profile(root, data);
5370 * the only place that sets empty_size is btrfs_realloc_node, which
5371 * is not called recursively on allocations
5373 if (empty_size || root->ref_cows)
5374 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5375 num_bytes + 2 * 1024 * 1024, data,
5376 CHUNK_ALLOC_NO_FORCE);
5378 WARN_ON(num_bytes < root->sectorsize);
5379 ret = find_free_extent(trans, root, num_bytes, empty_size,
5380 search_start, search_end, hint_byte,
5383 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5384 num_bytes = num_bytes >> 1;
5385 num_bytes = num_bytes & ~(root->sectorsize - 1);
5386 num_bytes = max(num_bytes, min_alloc_size);
5387 do_chunk_alloc(trans, root->fs_info->extent_root,
5388 num_bytes, data, CHUNK_ALLOC_FORCE);
5391 if (ret == -ENOSPC && btrfs_test_opt(root, ENOSPC_DEBUG)) {
5392 struct btrfs_space_info *sinfo;
5394 sinfo = __find_space_info(root->fs_info, data);
5395 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5396 "wanted %llu\n", (unsigned long long)data,
5397 (unsigned long long)num_bytes);
5398 dump_space_info(sinfo, num_bytes, 1);
5401 trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
5406 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
5408 struct btrfs_block_group_cache *cache;
5411 cache = btrfs_lookup_block_group(root->fs_info, start);
5413 printk(KERN_ERR "Unable to find block group for %llu\n",
5414 (unsigned long long)start);
5418 if (btrfs_test_opt(root, DISCARD))
5419 ret = btrfs_discard_extent(root, start, len, NULL);
5421 btrfs_add_free_space(cache, start, len);
5422 btrfs_update_reserved_bytes(cache, len, 0, 1);
5423 btrfs_put_block_group(cache);
5425 trace_btrfs_reserved_extent_free(root, start, len);
5430 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5431 struct btrfs_root *root,
5432 u64 parent, u64 root_objectid,
5433 u64 flags, u64 owner, u64 offset,
5434 struct btrfs_key *ins, int ref_mod)
5437 struct btrfs_fs_info *fs_info = root->fs_info;
5438 struct btrfs_extent_item *extent_item;
5439 struct btrfs_extent_inline_ref *iref;
5440 struct btrfs_path *path;
5441 struct extent_buffer *leaf;
5446 type = BTRFS_SHARED_DATA_REF_KEY;
5448 type = BTRFS_EXTENT_DATA_REF_KEY;
5450 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5452 path = btrfs_alloc_path();
5456 path->leave_spinning = 1;
5457 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5461 leaf = path->nodes[0];
5462 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5463 struct btrfs_extent_item);
5464 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5465 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5466 btrfs_set_extent_flags(leaf, extent_item,
5467 flags | BTRFS_EXTENT_FLAG_DATA);
5469 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5470 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5472 struct btrfs_shared_data_ref *ref;
5473 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5474 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5475 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5477 struct btrfs_extent_data_ref *ref;
5478 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5479 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5480 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5481 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5482 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5485 btrfs_mark_buffer_dirty(path->nodes[0]);
5486 btrfs_free_path(path);
5488 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5490 printk(KERN_ERR "btrfs update block group failed for %llu "
5491 "%llu\n", (unsigned long long)ins->objectid,
5492 (unsigned long long)ins->offset);
5498 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5499 struct btrfs_root *root,
5500 u64 parent, u64 root_objectid,
5501 u64 flags, struct btrfs_disk_key *key,
5502 int level, struct btrfs_key *ins)
5505 struct btrfs_fs_info *fs_info = root->fs_info;
5506 struct btrfs_extent_item *extent_item;
5507 struct btrfs_tree_block_info *block_info;
5508 struct btrfs_extent_inline_ref *iref;
5509 struct btrfs_path *path;
5510 struct extent_buffer *leaf;
5511 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5513 path = btrfs_alloc_path();
5517 path->leave_spinning = 1;
5518 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5522 leaf = path->nodes[0];
5523 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5524 struct btrfs_extent_item);
5525 btrfs_set_extent_refs(leaf, extent_item, 1);
5526 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5527 btrfs_set_extent_flags(leaf, extent_item,
5528 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5529 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5531 btrfs_set_tree_block_key(leaf, block_info, key);
5532 btrfs_set_tree_block_level(leaf, block_info, level);
5534 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5536 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5537 btrfs_set_extent_inline_ref_type(leaf, iref,
5538 BTRFS_SHARED_BLOCK_REF_KEY);
5539 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5541 btrfs_set_extent_inline_ref_type(leaf, iref,
5542 BTRFS_TREE_BLOCK_REF_KEY);
5543 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5546 btrfs_mark_buffer_dirty(leaf);
5547 btrfs_free_path(path);
5549 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5551 printk(KERN_ERR "btrfs update block group failed for %llu "
5552 "%llu\n", (unsigned long long)ins->objectid,
5553 (unsigned long long)ins->offset);
5559 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5560 struct btrfs_root *root,
5561 u64 root_objectid, u64 owner,
5562 u64 offset, struct btrfs_key *ins)
5566 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5568 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5569 0, root_objectid, owner, offset,
5570 BTRFS_ADD_DELAYED_EXTENT, NULL);
5575 * this is used by the tree logging recovery code. It records that
5576 * an extent has been allocated and makes sure to clear the free
5577 * space cache bits as well
5579 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5580 struct btrfs_root *root,
5581 u64 root_objectid, u64 owner, u64 offset,
5582 struct btrfs_key *ins)
5585 struct btrfs_block_group_cache *block_group;
5586 struct btrfs_caching_control *caching_ctl;
5587 u64 start = ins->objectid;
5588 u64 num_bytes = ins->offset;
5590 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5591 cache_block_group(block_group, trans, NULL, 0);
5592 caching_ctl = get_caching_control(block_group);
5595 BUG_ON(!block_group_cache_done(block_group));
5596 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5599 mutex_lock(&caching_ctl->mutex);
5601 if (start >= caching_ctl->progress) {
5602 ret = add_excluded_extent(root, start, num_bytes);
5604 } else if (start + num_bytes <= caching_ctl->progress) {
5605 ret = btrfs_remove_free_space(block_group,
5609 num_bytes = caching_ctl->progress - start;
5610 ret = btrfs_remove_free_space(block_group,
5614 start = caching_ctl->progress;
5615 num_bytes = ins->objectid + ins->offset -
5616 caching_ctl->progress;
5617 ret = add_excluded_extent(root, start, num_bytes);
5621 mutex_unlock(&caching_ctl->mutex);
5622 put_caching_control(caching_ctl);
5625 ret = btrfs_update_reserved_bytes(block_group, ins->offset, 1, 1);
5627 btrfs_put_block_group(block_group);
5628 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5629 0, owner, offset, ins, 1);
5633 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5634 struct btrfs_root *root,
5635 u64 bytenr, u32 blocksize,
5638 struct extent_buffer *buf;
5640 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5642 return ERR_PTR(-ENOMEM);
5643 btrfs_set_header_generation(buf, trans->transid);
5644 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
5645 btrfs_tree_lock(buf);
5646 clean_tree_block(trans, root, buf);
5648 btrfs_set_lock_blocking(buf);
5649 btrfs_set_buffer_uptodate(buf);
5651 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5653 * we allow two log transactions at a time, use different
5654 * EXENT bit to differentiate dirty pages.
5656 if (root->log_transid % 2 == 0)
5657 set_extent_dirty(&root->dirty_log_pages, buf->start,
5658 buf->start + buf->len - 1, GFP_NOFS);
5660 set_extent_new(&root->dirty_log_pages, buf->start,
5661 buf->start + buf->len - 1, GFP_NOFS);
5663 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5664 buf->start + buf->len - 1, GFP_NOFS);
5666 trans->blocks_used++;
5667 /* this returns a buffer locked for blocking */
5671 static struct btrfs_block_rsv *
5672 use_block_rsv(struct btrfs_trans_handle *trans,
5673 struct btrfs_root *root, u32 blocksize)
5675 struct btrfs_block_rsv *block_rsv;
5676 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
5679 block_rsv = get_block_rsv(trans, root);
5681 if (block_rsv->size == 0) {
5682 ret = reserve_metadata_bytes(trans, root, block_rsv,
5685 * If we couldn't reserve metadata bytes try and use some from
5686 * the global reserve.
5688 if (ret && block_rsv != global_rsv) {
5689 ret = block_rsv_use_bytes(global_rsv, blocksize);
5692 return ERR_PTR(ret);
5694 return ERR_PTR(ret);
5699 ret = block_rsv_use_bytes(block_rsv, blocksize);
5704 ret = reserve_metadata_bytes(trans, root, block_rsv, blocksize,
5707 spin_lock(&block_rsv->lock);
5708 block_rsv->size += blocksize;
5709 spin_unlock(&block_rsv->lock);
5711 } else if (ret && block_rsv != global_rsv) {
5712 ret = block_rsv_use_bytes(global_rsv, blocksize);
5718 return ERR_PTR(-ENOSPC);
5721 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5723 block_rsv_add_bytes(block_rsv, blocksize, 0);
5724 block_rsv_release_bytes(block_rsv, NULL, 0);
5728 * finds a free extent and does all the dirty work required for allocation
5729 * returns the key for the extent through ins, and a tree buffer for
5730 * the first block of the extent through buf.
5732 * returns the tree buffer or NULL.
5734 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5735 struct btrfs_root *root, u32 blocksize,
5736 u64 parent, u64 root_objectid,
5737 struct btrfs_disk_key *key, int level,
5738 u64 hint, u64 empty_size)
5740 struct btrfs_key ins;
5741 struct btrfs_block_rsv *block_rsv;
5742 struct extent_buffer *buf;
5747 block_rsv = use_block_rsv(trans, root, blocksize);
5748 if (IS_ERR(block_rsv))
5749 return ERR_CAST(block_rsv);
5751 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5752 empty_size, hint, (u64)-1, &ins, 0);
5754 unuse_block_rsv(block_rsv, blocksize);
5755 return ERR_PTR(ret);
5758 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5760 BUG_ON(IS_ERR(buf));
5762 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5764 parent = ins.objectid;
5765 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5769 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5770 struct btrfs_delayed_extent_op *extent_op;
5771 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5774 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5776 memset(&extent_op->key, 0, sizeof(extent_op->key));
5777 extent_op->flags_to_set = flags;
5778 extent_op->update_key = 1;
5779 extent_op->update_flags = 1;
5780 extent_op->is_data = 0;
5782 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5783 ins.offset, parent, root_objectid,
5784 level, BTRFS_ADD_DELAYED_EXTENT,
5791 struct walk_control {
5792 u64 refs[BTRFS_MAX_LEVEL];
5793 u64 flags[BTRFS_MAX_LEVEL];
5794 struct btrfs_key update_progress;
5804 #define DROP_REFERENCE 1
5805 #define UPDATE_BACKREF 2
5807 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5808 struct btrfs_root *root,
5809 struct walk_control *wc,
5810 struct btrfs_path *path)
5818 struct btrfs_key key;
5819 struct extent_buffer *eb;
5824 if (path->slots[wc->level] < wc->reada_slot) {
5825 wc->reada_count = wc->reada_count * 2 / 3;
5826 wc->reada_count = max(wc->reada_count, 2);
5828 wc->reada_count = wc->reada_count * 3 / 2;
5829 wc->reada_count = min_t(int, wc->reada_count,
5830 BTRFS_NODEPTRS_PER_BLOCK(root));
5833 eb = path->nodes[wc->level];
5834 nritems = btrfs_header_nritems(eb);
5835 blocksize = btrfs_level_size(root, wc->level - 1);
5837 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5838 if (nread >= wc->reada_count)
5842 bytenr = btrfs_node_blockptr(eb, slot);
5843 generation = btrfs_node_ptr_generation(eb, slot);
5845 if (slot == path->slots[wc->level])
5848 if (wc->stage == UPDATE_BACKREF &&
5849 generation <= root->root_key.offset)
5852 /* We don't lock the tree block, it's OK to be racy here */
5853 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5858 if (wc->stage == DROP_REFERENCE) {
5862 if (wc->level == 1 &&
5863 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5865 if (!wc->update_ref ||
5866 generation <= root->root_key.offset)
5868 btrfs_node_key_to_cpu(eb, &key, slot);
5869 ret = btrfs_comp_cpu_keys(&key,
5870 &wc->update_progress);
5874 if (wc->level == 1 &&
5875 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5879 ret = readahead_tree_block(root, bytenr, blocksize,
5885 wc->reada_slot = slot;
5889 * hepler to process tree block while walking down the tree.
5891 * when wc->stage == UPDATE_BACKREF, this function updates
5892 * back refs for pointers in the block.
5894 * NOTE: return value 1 means we should stop walking down.
5896 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5897 struct btrfs_root *root,
5898 struct btrfs_path *path,
5899 struct walk_control *wc, int lookup_info)
5901 int level = wc->level;
5902 struct extent_buffer *eb = path->nodes[level];
5903 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5906 if (wc->stage == UPDATE_BACKREF &&
5907 btrfs_header_owner(eb) != root->root_key.objectid)
5911 * when reference count of tree block is 1, it won't increase
5912 * again. once full backref flag is set, we never clear it.
5915 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5916 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5917 BUG_ON(!path->locks[level]);
5918 ret = btrfs_lookup_extent_info(trans, root,
5923 BUG_ON(wc->refs[level] == 0);
5926 if (wc->stage == DROP_REFERENCE) {
5927 if (wc->refs[level] > 1)
5930 if (path->locks[level] && !wc->keep_locks) {
5931 btrfs_tree_unlock_rw(eb, path->locks[level]);
5932 path->locks[level] = 0;
5937 /* wc->stage == UPDATE_BACKREF */
5938 if (!(wc->flags[level] & flag)) {
5939 BUG_ON(!path->locks[level]);
5940 ret = btrfs_inc_ref(trans, root, eb, 1);
5942 ret = btrfs_dec_ref(trans, root, eb, 0);
5944 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5947 wc->flags[level] |= flag;
5951 * the block is shared by multiple trees, so it's not good to
5952 * keep the tree lock
5954 if (path->locks[level] && level > 0) {
5955 btrfs_tree_unlock_rw(eb, path->locks[level]);
5956 path->locks[level] = 0;
5962 * hepler to process tree block pointer.
5964 * when wc->stage == DROP_REFERENCE, this function checks
5965 * reference count of the block pointed to. if the block
5966 * is shared and we need update back refs for the subtree
5967 * rooted at the block, this function changes wc->stage to
5968 * UPDATE_BACKREF. if the block is shared and there is no
5969 * need to update back, this function drops the reference
5972 * NOTE: return value 1 means we should stop walking down.
5974 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5975 struct btrfs_root *root,
5976 struct btrfs_path *path,
5977 struct walk_control *wc, int *lookup_info)
5983 struct btrfs_key key;
5984 struct extent_buffer *next;
5985 int level = wc->level;
5989 generation = btrfs_node_ptr_generation(path->nodes[level],
5990 path->slots[level]);
5992 * if the lower level block was created before the snapshot
5993 * was created, we know there is no need to update back refs
5996 if (wc->stage == UPDATE_BACKREF &&
5997 generation <= root->root_key.offset) {
6002 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
6003 blocksize = btrfs_level_size(root, level - 1);
6005 next = btrfs_find_tree_block(root, bytenr, blocksize);
6007 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
6012 btrfs_tree_lock(next);
6013 btrfs_set_lock_blocking(next);
6015 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6016 &wc->refs[level - 1],
6017 &wc->flags[level - 1]);
6019 BUG_ON(wc->refs[level - 1] == 0);
6022 if (wc->stage == DROP_REFERENCE) {
6023 if (wc->refs[level - 1] > 1) {
6025 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6028 if (!wc->update_ref ||
6029 generation <= root->root_key.offset)
6032 btrfs_node_key_to_cpu(path->nodes[level], &key,
6033 path->slots[level]);
6034 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
6038 wc->stage = UPDATE_BACKREF;
6039 wc->shared_level = level - 1;
6043 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6047 if (!btrfs_buffer_uptodate(next, generation)) {
6048 btrfs_tree_unlock(next);
6049 free_extent_buffer(next);
6055 if (reada && level == 1)
6056 reada_walk_down(trans, root, wc, path);
6057 next = read_tree_block(root, bytenr, blocksize, generation);
6060 btrfs_tree_lock(next);
6061 btrfs_set_lock_blocking(next);
6065 BUG_ON(level != btrfs_header_level(next));
6066 path->nodes[level] = next;
6067 path->slots[level] = 0;
6068 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6074 wc->refs[level - 1] = 0;
6075 wc->flags[level - 1] = 0;
6076 if (wc->stage == DROP_REFERENCE) {
6077 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6078 parent = path->nodes[level]->start;
6080 BUG_ON(root->root_key.objectid !=
6081 btrfs_header_owner(path->nodes[level]));
6085 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
6086 root->root_key.objectid, level - 1, 0);
6089 btrfs_tree_unlock(next);
6090 free_extent_buffer(next);
6096 * hepler to process tree block while walking up the tree.
6098 * when wc->stage == DROP_REFERENCE, this function drops
6099 * reference count on the block.
6101 * when wc->stage == UPDATE_BACKREF, this function changes
6102 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6103 * to UPDATE_BACKREF previously while processing the block.
6105 * NOTE: return value 1 means we should stop walking up.
6107 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6108 struct btrfs_root *root,
6109 struct btrfs_path *path,
6110 struct walk_control *wc)
6113 int level = wc->level;
6114 struct extent_buffer *eb = path->nodes[level];
6117 if (wc->stage == UPDATE_BACKREF) {
6118 BUG_ON(wc->shared_level < level);
6119 if (level < wc->shared_level)
6122 ret = find_next_key(path, level + 1, &wc->update_progress);
6126 wc->stage = DROP_REFERENCE;
6127 wc->shared_level = -1;
6128 path->slots[level] = 0;
6131 * check reference count again if the block isn't locked.
6132 * we should start walking down the tree again if reference
6135 if (!path->locks[level]) {
6137 btrfs_tree_lock(eb);
6138 btrfs_set_lock_blocking(eb);
6139 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6141 ret = btrfs_lookup_extent_info(trans, root,
6146 BUG_ON(wc->refs[level] == 0);
6147 if (wc->refs[level] == 1) {
6148 btrfs_tree_unlock_rw(eb, path->locks[level]);
6154 /* wc->stage == DROP_REFERENCE */
6155 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6157 if (wc->refs[level] == 1) {
6159 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6160 ret = btrfs_dec_ref(trans, root, eb, 1);
6162 ret = btrfs_dec_ref(trans, root, eb, 0);
6165 /* make block locked assertion in clean_tree_block happy */
6166 if (!path->locks[level] &&
6167 btrfs_header_generation(eb) == trans->transid) {
6168 btrfs_tree_lock(eb);
6169 btrfs_set_lock_blocking(eb);
6170 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6172 clean_tree_block(trans, root, eb);
6175 if (eb == root->node) {
6176 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6179 BUG_ON(root->root_key.objectid !=
6180 btrfs_header_owner(eb));
6182 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6183 parent = path->nodes[level + 1]->start;
6185 BUG_ON(root->root_key.objectid !=
6186 btrfs_header_owner(path->nodes[level + 1]));
6189 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6191 wc->refs[level] = 0;
6192 wc->flags[level] = 0;
6196 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6197 struct btrfs_root *root,
6198 struct btrfs_path *path,
6199 struct walk_control *wc)
6201 int level = wc->level;
6202 int lookup_info = 1;
6205 while (level >= 0) {
6206 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6213 if (path->slots[level] >=
6214 btrfs_header_nritems(path->nodes[level]))
6217 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6219 path->slots[level]++;
6228 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6229 struct btrfs_root *root,
6230 struct btrfs_path *path,
6231 struct walk_control *wc, int max_level)
6233 int level = wc->level;
6236 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6237 while (level < max_level && path->nodes[level]) {
6239 if (path->slots[level] + 1 <
6240 btrfs_header_nritems(path->nodes[level])) {
6241 path->slots[level]++;
6244 ret = walk_up_proc(trans, root, path, wc);
6248 if (path->locks[level]) {
6249 btrfs_tree_unlock_rw(path->nodes[level],
6250 path->locks[level]);
6251 path->locks[level] = 0;
6253 free_extent_buffer(path->nodes[level]);
6254 path->nodes[level] = NULL;
6262 * drop a subvolume tree.
6264 * this function traverses the tree freeing any blocks that only
6265 * referenced by the tree.
6267 * when a shared tree block is found. this function decreases its
6268 * reference count by one. if update_ref is true, this function
6269 * also make sure backrefs for the shared block and all lower level
6270 * blocks are properly updated.
6272 int btrfs_drop_snapshot(struct btrfs_root *root,
6273 struct btrfs_block_rsv *block_rsv, int update_ref)
6275 struct btrfs_path *path;
6276 struct btrfs_trans_handle *trans;
6277 struct btrfs_root *tree_root = root->fs_info->tree_root;
6278 struct btrfs_root_item *root_item = &root->root_item;
6279 struct walk_control *wc;
6280 struct btrfs_key key;
6285 path = btrfs_alloc_path();
6289 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6291 btrfs_free_path(path);
6295 trans = btrfs_start_transaction(tree_root, 0);
6296 BUG_ON(IS_ERR(trans));
6299 trans->block_rsv = block_rsv;
6301 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6302 level = btrfs_header_level(root->node);
6303 path->nodes[level] = btrfs_lock_root_node(root);
6304 btrfs_set_lock_blocking(path->nodes[level]);
6305 path->slots[level] = 0;
6306 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6307 memset(&wc->update_progress, 0,
6308 sizeof(wc->update_progress));
6310 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6311 memcpy(&wc->update_progress, &key,
6312 sizeof(wc->update_progress));
6314 level = root_item->drop_level;
6316 path->lowest_level = level;
6317 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6318 path->lowest_level = 0;
6326 * unlock our path, this is safe because only this
6327 * function is allowed to delete this snapshot
6329 btrfs_unlock_up_safe(path, 0);
6331 level = btrfs_header_level(root->node);
6333 btrfs_tree_lock(path->nodes[level]);
6334 btrfs_set_lock_blocking(path->nodes[level]);
6336 ret = btrfs_lookup_extent_info(trans, root,
6337 path->nodes[level]->start,
6338 path->nodes[level]->len,
6342 BUG_ON(wc->refs[level] == 0);
6344 if (level == root_item->drop_level)
6347 btrfs_tree_unlock(path->nodes[level]);
6348 WARN_ON(wc->refs[level] != 1);
6354 wc->shared_level = -1;
6355 wc->stage = DROP_REFERENCE;
6356 wc->update_ref = update_ref;
6358 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6361 ret = walk_down_tree(trans, root, path, wc);
6367 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6374 BUG_ON(wc->stage != DROP_REFERENCE);
6378 if (wc->stage == DROP_REFERENCE) {
6380 btrfs_node_key(path->nodes[level],
6381 &root_item->drop_progress,
6382 path->slots[level]);
6383 root_item->drop_level = level;
6386 BUG_ON(wc->level == 0);
6387 if (btrfs_should_end_transaction(trans, tree_root)) {
6388 ret = btrfs_update_root(trans, tree_root,
6393 btrfs_end_transaction_throttle(trans, tree_root);
6394 trans = btrfs_start_transaction(tree_root, 0);
6395 BUG_ON(IS_ERR(trans));
6397 trans->block_rsv = block_rsv;
6400 btrfs_release_path(path);
6403 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6406 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6407 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6411 /* if we fail to delete the orphan item this time
6412 * around, it'll get picked up the next time.
6414 * The most common failure here is just -ENOENT.
6416 btrfs_del_orphan_item(trans, tree_root,
6417 root->root_key.objectid);
6421 if (root->in_radix) {
6422 btrfs_free_fs_root(tree_root->fs_info, root);
6424 free_extent_buffer(root->node);
6425 free_extent_buffer(root->commit_root);
6429 btrfs_end_transaction_throttle(trans, tree_root);
6431 btrfs_free_path(path);
6436 * drop subtree rooted at tree block 'node'.
6438 * NOTE: this function will unlock and release tree block 'node'
6440 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6441 struct btrfs_root *root,
6442 struct extent_buffer *node,
6443 struct extent_buffer *parent)
6445 struct btrfs_path *path;
6446 struct walk_control *wc;
6452 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6454 path = btrfs_alloc_path();
6458 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6460 btrfs_free_path(path);
6464 btrfs_assert_tree_locked(parent);
6465 parent_level = btrfs_header_level(parent);
6466 extent_buffer_get(parent);
6467 path->nodes[parent_level] = parent;
6468 path->slots[parent_level] = btrfs_header_nritems(parent);
6470 btrfs_assert_tree_locked(node);
6471 level = btrfs_header_level(node);
6472 path->nodes[level] = node;
6473 path->slots[level] = 0;
6474 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6476 wc->refs[parent_level] = 1;
6477 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6479 wc->shared_level = -1;
6480 wc->stage = DROP_REFERENCE;
6483 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6486 wret = walk_down_tree(trans, root, path, wc);
6492 wret = walk_up_tree(trans, root, path, wc, parent_level);
6500 btrfs_free_path(path);
6504 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
6507 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
6508 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
6511 * we add in the count of missing devices because we want
6512 * to make sure that any RAID levels on a degraded FS
6513 * continue to be honored.
6515 num_devices = root->fs_info->fs_devices->rw_devices +
6516 root->fs_info->fs_devices->missing_devices;
6518 if (num_devices == 1) {
6519 stripped |= BTRFS_BLOCK_GROUP_DUP;
6520 stripped = flags & ~stripped;
6522 /* turn raid0 into single device chunks */
6523 if (flags & BTRFS_BLOCK_GROUP_RAID0)
6526 /* turn mirroring into duplication */
6527 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
6528 BTRFS_BLOCK_GROUP_RAID10))
6529 return stripped | BTRFS_BLOCK_GROUP_DUP;
6532 /* they already had raid on here, just return */
6533 if (flags & stripped)
6536 stripped |= BTRFS_BLOCK_GROUP_DUP;
6537 stripped = flags & ~stripped;
6539 /* switch duplicated blocks with raid1 */
6540 if (flags & BTRFS_BLOCK_GROUP_DUP)
6541 return stripped | BTRFS_BLOCK_GROUP_RAID1;
6543 /* turn single device chunks into raid0 */
6544 return stripped | BTRFS_BLOCK_GROUP_RAID0;
6549 static int set_block_group_ro(struct btrfs_block_group_cache *cache, int force)
6551 struct btrfs_space_info *sinfo = cache->space_info;
6553 u64 min_allocable_bytes;
6558 * We need some metadata space and system metadata space for
6559 * allocating chunks in some corner cases until we force to set
6560 * it to be readonly.
6563 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
6565 min_allocable_bytes = 1 * 1024 * 1024;
6567 min_allocable_bytes = 0;
6569 spin_lock(&sinfo->lock);
6570 spin_lock(&cache->lock);
6577 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
6578 cache->bytes_super - btrfs_block_group_used(&cache->item);
6580 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
6581 sinfo->bytes_may_use + sinfo->bytes_readonly +
6582 cache->reserved_pinned + num_bytes + min_allocable_bytes <=
6583 sinfo->total_bytes) {
6584 sinfo->bytes_readonly += num_bytes;
6585 sinfo->bytes_reserved += cache->reserved_pinned;
6586 cache->reserved_pinned = 0;
6591 spin_unlock(&cache->lock);
6592 spin_unlock(&sinfo->lock);
6596 int btrfs_set_block_group_ro(struct btrfs_root *root,
6597 struct btrfs_block_group_cache *cache)
6600 struct btrfs_trans_handle *trans;
6606 trans = btrfs_join_transaction(root);
6607 BUG_ON(IS_ERR(trans));
6609 alloc_flags = update_block_group_flags(root, cache->flags);
6610 if (alloc_flags != cache->flags)
6611 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6614 ret = set_block_group_ro(cache, 0);
6617 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
6618 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6622 ret = set_block_group_ro(cache, 0);
6624 btrfs_end_transaction(trans, root);
6628 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
6629 struct btrfs_root *root, u64 type)
6631 u64 alloc_flags = get_alloc_profile(root, type);
6632 return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6637 * helper to account the unused space of all the readonly block group in the
6638 * list. takes mirrors into account.
6640 static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
6642 struct btrfs_block_group_cache *block_group;
6646 list_for_each_entry(block_group, groups_list, list) {
6647 spin_lock(&block_group->lock);
6649 if (!block_group->ro) {
6650 spin_unlock(&block_group->lock);
6654 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
6655 BTRFS_BLOCK_GROUP_RAID10 |
6656 BTRFS_BLOCK_GROUP_DUP))
6661 free_bytes += (block_group->key.offset -
6662 btrfs_block_group_used(&block_group->item)) *
6665 spin_unlock(&block_group->lock);
6672 * helper to account the unused space of all the readonly block group in the
6673 * space_info. takes mirrors into account.
6675 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
6680 spin_lock(&sinfo->lock);
6682 for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
6683 if (!list_empty(&sinfo->block_groups[i]))
6684 free_bytes += __btrfs_get_ro_block_group_free_space(
6685 &sinfo->block_groups[i]);
6687 spin_unlock(&sinfo->lock);
6692 int btrfs_set_block_group_rw(struct btrfs_root *root,
6693 struct btrfs_block_group_cache *cache)
6695 struct btrfs_space_info *sinfo = cache->space_info;
6700 spin_lock(&sinfo->lock);
6701 spin_lock(&cache->lock);
6702 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
6703 cache->bytes_super - btrfs_block_group_used(&cache->item);
6704 sinfo->bytes_readonly -= num_bytes;
6706 spin_unlock(&cache->lock);
6707 spin_unlock(&sinfo->lock);
6712 * checks to see if its even possible to relocate this block group.
6714 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
6715 * ok to go ahead and try.
6717 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
6719 struct btrfs_block_group_cache *block_group;
6720 struct btrfs_space_info *space_info;
6721 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6722 struct btrfs_device *device;
6726 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
6728 /* odd, couldn't find the block group, leave it alone */
6732 /* no bytes used, we're good */
6733 if (!btrfs_block_group_used(&block_group->item))
6736 space_info = block_group->space_info;
6737 spin_lock(&space_info->lock);
6739 full = space_info->full;
6742 * if this is the last block group we have in this space, we can't
6743 * relocate it unless we're able to allocate a new chunk below.
6745 * Otherwise, we need to make sure we have room in the space to handle
6746 * all of the extents from this block group. If we can, we're good
6748 if ((space_info->total_bytes != block_group->key.offset) &&
6749 (space_info->bytes_used + space_info->bytes_reserved +
6750 space_info->bytes_pinned + space_info->bytes_readonly +
6751 btrfs_block_group_used(&block_group->item) <
6752 space_info->total_bytes)) {
6753 spin_unlock(&space_info->lock);
6756 spin_unlock(&space_info->lock);
6759 * ok we don't have enough space, but maybe we have free space on our
6760 * devices to allocate new chunks for relocation, so loop through our
6761 * alloc devices and guess if we have enough space. However, if we
6762 * were marked as full, then we know there aren't enough chunks, and we
6769 mutex_lock(&root->fs_info->chunk_mutex);
6770 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
6771 u64 min_free = btrfs_block_group_used(&block_group->item);
6775 * check to make sure we can actually find a chunk with enough
6776 * space to fit our block group in.
6778 if (device->total_bytes > device->bytes_used + min_free) {
6779 ret = find_free_dev_extent(NULL, device, min_free,
6786 mutex_unlock(&root->fs_info->chunk_mutex);
6788 btrfs_put_block_group(block_group);
6792 static int find_first_block_group(struct btrfs_root *root,
6793 struct btrfs_path *path, struct btrfs_key *key)
6796 struct btrfs_key found_key;
6797 struct extent_buffer *leaf;
6800 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
6805 slot = path->slots[0];
6806 leaf = path->nodes[0];
6807 if (slot >= btrfs_header_nritems(leaf)) {
6808 ret = btrfs_next_leaf(root, path);
6815 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6817 if (found_key.objectid >= key->objectid &&
6818 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
6828 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
6830 struct btrfs_block_group_cache *block_group;
6834 struct inode *inode;
6836 block_group = btrfs_lookup_first_block_group(info, last);
6837 while (block_group) {
6838 spin_lock(&block_group->lock);
6839 if (block_group->iref)
6841 spin_unlock(&block_group->lock);
6842 block_group = next_block_group(info->tree_root,
6852 inode = block_group->inode;
6853 block_group->iref = 0;
6854 block_group->inode = NULL;
6855 spin_unlock(&block_group->lock);
6857 last = block_group->key.objectid + block_group->key.offset;
6858 btrfs_put_block_group(block_group);
6862 int btrfs_free_block_groups(struct btrfs_fs_info *info)
6864 struct btrfs_block_group_cache *block_group;
6865 struct btrfs_space_info *space_info;
6866 struct btrfs_caching_control *caching_ctl;
6869 down_write(&info->extent_commit_sem);
6870 while (!list_empty(&info->caching_block_groups)) {
6871 caching_ctl = list_entry(info->caching_block_groups.next,
6872 struct btrfs_caching_control, list);
6873 list_del(&caching_ctl->list);
6874 put_caching_control(caching_ctl);
6876 up_write(&info->extent_commit_sem);
6878 spin_lock(&info->block_group_cache_lock);
6879 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
6880 block_group = rb_entry(n, struct btrfs_block_group_cache,
6882 rb_erase(&block_group->cache_node,
6883 &info->block_group_cache_tree);
6884 spin_unlock(&info->block_group_cache_lock);
6886 down_write(&block_group->space_info->groups_sem);
6887 list_del(&block_group->list);
6888 up_write(&block_group->space_info->groups_sem);
6890 if (block_group->cached == BTRFS_CACHE_STARTED)
6891 wait_block_group_cache_done(block_group);
6894 * We haven't cached this block group, which means we could
6895 * possibly have excluded extents on this block group.
6897 if (block_group->cached == BTRFS_CACHE_NO)
6898 free_excluded_extents(info->extent_root, block_group);
6900 btrfs_remove_free_space_cache(block_group);
6901 btrfs_put_block_group(block_group);
6903 spin_lock(&info->block_group_cache_lock);
6905 spin_unlock(&info->block_group_cache_lock);
6907 /* now that all the block groups are freed, go through and
6908 * free all the space_info structs. This is only called during
6909 * the final stages of unmount, and so we know nobody is
6910 * using them. We call synchronize_rcu() once before we start,
6911 * just to be on the safe side.
6915 release_global_block_rsv(info);
6917 while(!list_empty(&info->space_info)) {
6918 space_info = list_entry(info->space_info.next,
6919 struct btrfs_space_info,
6921 if (space_info->bytes_pinned > 0 ||
6922 space_info->bytes_reserved > 0) {
6924 dump_space_info(space_info, 0, 0);
6926 list_del(&space_info->list);
6932 static void __link_block_group(struct btrfs_space_info *space_info,
6933 struct btrfs_block_group_cache *cache)
6935 int index = get_block_group_index(cache);
6937 down_write(&space_info->groups_sem);
6938 list_add_tail(&cache->list, &space_info->block_groups[index]);
6939 up_write(&space_info->groups_sem);
6942 int btrfs_read_block_groups(struct btrfs_root *root)
6944 struct btrfs_path *path;
6946 struct btrfs_block_group_cache *cache;
6947 struct btrfs_fs_info *info = root->fs_info;
6948 struct btrfs_space_info *space_info;
6949 struct btrfs_key key;
6950 struct btrfs_key found_key;
6951 struct extent_buffer *leaf;
6955 root = info->extent_root;
6958 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
6959 path = btrfs_alloc_path();
6964 cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy);
6965 if (cache_gen != 0 &&
6966 btrfs_super_generation(&root->fs_info->super_copy) != cache_gen)
6968 if (btrfs_test_opt(root, CLEAR_CACHE))
6970 if (!btrfs_test_opt(root, SPACE_CACHE) && cache_gen)
6971 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
6974 ret = find_first_block_group(root, path, &key);
6979 leaf = path->nodes[0];
6980 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6981 cache = kzalloc(sizeof(*cache), GFP_NOFS);
6986 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
6988 if (!cache->free_space_ctl) {
6994 atomic_set(&cache->count, 1);
6995 spin_lock_init(&cache->lock);
6996 cache->fs_info = info;
6997 INIT_LIST_HEAD(&cache->list);
6998 INIT_LIST_HEAD(&cache->cluster_list);
7001 cache->disk_cache_state = BTRFS_DC_CLEAR;
7003 read_extent_buffer(leaf, &cache->item,
7004 btrfs_item_ptr_offset(leaf, path->slots[0]),
7005 sizeof(cache->item));
7006 memcpy(&cache->key, &found_key, sizeof(found_key));
7008 key.objectid = found_key.objectid + found_key.offset;
7009 btrfs_release_path(path);
7010 cache->flags = btrfs_block_group_flags(&cache->item);
7011 cache->sectorsize = root->sectorsize;
7013 btrfs_init_free_space_ctl(cache);
7016 * We need to exclude the super stripes now so that the space
7017 * info has super bytes accounted for, otherwise we'll think
7018 * we have more space than we actually do.
7020 exclude_super_stripes(root, cache);
7023 * check for two cases, either we are full, and therefore
7024 * don't need to bother with the caching work since we won't
7025 * find any space, or we are empty, and we can just add all
7026 * the space in and be done with it. This saves us _alot_ of
7027 * time, particularly in the full case.
7029 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
7030 cache->last_byte_to_unpin = (u64)-1;
7031 cache->cached = BTRFS_CACHE_FINISHED;
7032 free_excluded_extents(root, cache);
7033 } else if (btrfs_block_group_used(&cache->item) == 0) {
7034 cache->last_byte_to_unpin = (u64)-1;
7035 cache->cached = BTRFS_CACHE_FINISHED;
7036 add_new_free_space(cache, root->fs_info,
7038 found_key.objectid +
7040 free_excluded_extents(root, cache);
7043 ret = update_space_info(info, cache->flags, found_key.offset,
7044 btrfs_block_group_used(&cache->item),
7047 cache->space_info = space_info;
7048 spin_lock(&cache->space_info->lock);
7049 cache->space_info->bytes_readonly += cache->bytes_super;
7050 spin_unlock(&cache->space_info->lock);
7052 __link_block_group(space_info, cache);
7054 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7057 set_avail_alloc_bits(root->fs_info, cache->flags);
7058 if (btrfs_chunk_readonly(root, cache->key.objectid))
7059 set_block_group_ro(cache, 1);
7062 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
7063 if (!(get_alloc_profile(root, space_info->flags) &
7064 (BTRFS_BLOCK_GROUP_RAID10 |
7065 BTRFS_BLOCK_GROUP_RAID1 |
7066 BTRFS_BLOCK_GROUP_DUP)))
7069 * avoid allocating from un-mirrored block group if there are
7070 * mirrored block groups.
7072 list_for_each_entry(cache, &space_info->block_groups[3], list)
7073 set_block_group_ro(cache, 1);
7074 list_for_each_entry(cache, &space_info->block_groups[4], list)
7075 set_block_group_ro(cache, 1);
7078 init_global_block_rsv(info);
7081 btrfs_free_path(path);
7085 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7086 struct btrfs_root *root, u64 bytes_used,
7087 u64 type, u64 chunk_objectid, u64 chunk_offset,
7091 struct btrfs_root *extent_root;
7092 struct btrfs_block_group_cache *cache;
7094 extent_root = root->fs_info->extent_root;
7096 root->fs_info->last_trans_log_full_commit = trans->transid;
7098 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7101 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7103 if (!cache->free_space_ctl) {
7108 cache->key.objectid = chunk_offset;
7109 cache->key.offset = size;
7110 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7111 cache->sectorsize = root->sectorsize;
7112 cache->fs_info = root->fs_info;
7114 atomic_set(&cache->count, 1);
7115 spin_lock_init(&cache->lock);
7116 INIT_LIST_HEAD(&cache->list);
7117 INIT_LIST_HEAD(&cache->cluster_list);
7119 btrfs_init_free_space_ctl(cache);
7121 btrfs_set_block_group_used(&cache->item, bytes_used);
7122 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7123 cache->flags = type;
7124 btrfs_set_block_group_flags(&cache->item, type);
7126 cache->last_byte_to_unpin = (u64)-1;
7127 cache->cached = BTRFS_CACHE_FINISHED;
7128 exclude_super_stripes(root, cache);
7130 add_new_free_space(cache, root->fs_info, chunk_offset,
7131 chunk_offset + size);
7133 free_excluded_extents(root, cache);
7135 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7136 &cache->space_info);
7139 spin_lock(&cache->space_info->lock);
7140 cache->space_info->bytes_readonly += cache->bytes_super;
7141 spin_unlock(&cache->space_info->lock);
7143 __link_block_group(cache->space_info, cache);
7145 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7148 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
7149 sizeof(cache->item));
7152 set_avail_alloc_bits(extent_root->fs_info, type);
7157 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7158 struct btrfs_root *root, u64 group_start)
7160 struct btrfs_path *path;
7161 struct btrfs_block_group_cache *block_group;
7162 struct btrfs_free_cluster *cluster;
7163 struct btrfs_root *tree_root = root->fs_info->tree_root;
7164 struct btrfs_key key;
7165 struct inode *inode;
7169 root = root->fs_info->extent_root;
7171 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7172 BUG_ON(!block_group);
7173 BUG_ON(!block_group->ro);
7176 * Free the reserved super bytes from this block group before
7179 free_excluded_extents(root, block_group);
7181 memcpy(&key, &block_group->key, sizeof(key));
7182 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
7183 BTRFS_BLOCK_GROUP_RAID1 |
7184 BTRFS_BLOCK_GROUP_RAID10))
7189 /* make sure this block group isn't part of an allocation cluster */
7190 cluster = &root->fs_info->data_alloc_cluster;
7191 spin_lock(&cluster->refill_lock);
7192 btrfs_return_cluster_to_free_space(block_group, cluster);
7193 spin_unlock(&cluster->refill_lock);
7196 * make sure this block group isn't part of a metadata
7197 * allocation cluster
7199 cluster = &root->fs_info->meta_alloc_cluster;
7200 spin_lock(&cluster->refill_lock);
7201 btrfs_return_cluster_to_free_space(block_group, cluster);
7202 spin_unlock(&cluster->refill_lock);
7204 path = btrfs_alloc_path();
7210 inode = lookup_free_space_inode(root, block_group, path);
7211 if (!IS_ERR(inode)) {
7212 ret = btrfs_orphan_add(trans, inode);
7215 /* One for the block groups ref */
7216 spin_lock(&block_group->lock);
7217 if (block_group->iref) {
7218 block_group->iref = 0;
7219 block_group->inode = NULL;
7220 spin_unlock(&block_group->lock);
7223 spin_unlock(&block_group->lock);
7225 /* One for our lookup ref */
7229 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
7230 key.offset = block_group->key.objectid;
7233 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
7237 btrfs_release_path(path);
7239 ret = btrfs_del_item(trans, tree_root, path);
7242 btrfs_release_path(path);
7245 spin_lock(&root->fs_info->block_group_cache_lock);
7246 rb_erase(&block_group->cache_node,
7247 &root->fs_info->block_group_cache_tree);
7248 spin_unlock(&root->fs_info->block_group_cache_lock);
7250 down_write(&block_group->space_info->groups_sem);
7252 * we must use list_del_init so people can check to see if they
7253 * are still on the list after taking the semaphore
7255 list_del_init(&block_group->list);
7256 up_write(&block_group->space_info->groups_sem);
7258 if (block_group->cached == BTRFS_CACHE_STARTED)
7259 wait_block_group_cache_done(block_group);
7261 btrfs_remove_free_space_cache(block_group);
7263 spin_lock(&block_group->space_info->lock);
7264 block_group->space_info->total_bytes -= block_group->key.offset;
7265 block_group->space_info->bytes_readonly -= block_group->key.offset;
7266 block_group->space_info->disk_total -= block_group->key.offset * factor;
7267 spin_unlock(&block_group->space_info->lock);
7269 memcpy(&key, &block_group->key, sizeof(key));
7271 btrfs_clear_space_info_full(root->fs_info);
7273 btrfs_put_block_group(block_group);
7274 btrfs_put_block_group(block_group);
7276 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
7282 ret = btrfs_del_item(trans, root, path);
7284 btrfs_free_path(path);
7288 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
7290 struct btrfs_space_info *space_info;
7291 struct btrfs_super_block *disk_super;
7297 disk_super = &fs_info->super_copy;
7298 if (!btrfs_super_root(disk_super))
7301 features = btrfs_super_incompat_flags(disk_super);
7302 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
7305 flags = BTRFS_BLOCK_GROUP_SYSTEM;
7306 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7311 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
7312 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7314 flags = BTRFS_BLOCK_GROUP_METADATA;
7315 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7319 flags = BTRFS_BLOCK_GROUP_DATA;
7320 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7326 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
7328 return unpin_extent_range(root, start, end);
7331 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
7332 u64 num_bytes, u64 *actual_bytes)
7334 return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
7337 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
7339 struct btrfs_fs_info *fs_info = root->fs_info;
7340 struct btrfs_block_group_cache *cache = NULL;
7347 cache = btrfs_lookup_block_group(fs_info, range->start);
7350 if (cache->key.objectid >= (range->start + range->len)) {
7351 btrfs_put_block_group(cache);
7355 start = max(range->start, cache->key.objectid);
7356 end = min(range->start + range->len,
7357 cache->key.objectid + cache->key.offset);
7359 if (end - start >= range->minlen) {
7360 if (!block_group_cache_done(cache)) {
7361 ret = cache_block_group(cache, NULL, root, 0);
7363 wait_block_group_cache_done(cache);
7365 ret = btrfs_trim_block_group(cache,
7371 trimmed += group_trimmed;
7373 btrfs_put_block_group(cache);
7378 cache = next_block_group(fs_info->tree_root, cache);
7381 range->len = trimmed;