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 static int update_block_group(struct btrfs_trans_handle *trans,
37 struct btrfs_root *root,
38 u64 bytenr, u64 num_bytes, int alloc);
39 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
40 u64 num_bytes, int reserve, int sinfo);
41 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
42 struct btrfs_root *root,
43 u64 bytenr, u64 num_bytes, u64 parent,
44 u64 root_objectid, u64 owner_objectid,
45 u64 owner_offset, int refs_to_drop,
46 struct btrfs_delayed_extent_op *extra_op);
47 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
48 struct extent_buffer *leaf,
49 struct btrfs_extent_item *ei);
50 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
51 struct btrfs_root *root,
52 u64 parent, u64 root_objectid,
53 u64 flags, u64 owner, u64 offset,
54 struct btrfs_key *ins, int ref_mod);
55 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
56 struct btrfs_root *root,
57 u64 parent, u64 root_objectid,
58 u64 flags, struct btrfs_disk_key *key,
59 int level, struct btrfs_key *ins);
60 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
61 struct btrfs_root *extent_root, u64 alloc_bytes,
62 u64 flags, int force);
63 static int find_next_key(struct btrfs_path *path, int level,
64 struct btrfs_key *key);
65 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
66 int dump_block_groups);
69 block_group_cache_done(struct btrfs_block_group_cache *cache)
72 return cache->cached == BTRFS_CACHE_FINISHED;
75 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
77 return (cache->flags & bits) == bits;
80 void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
82 atomic_inc(&cache->count);
85 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
87 if (atomic_dec_and_test(&cache->count)) {
88 WARN_ON(cache->pinned > 0);
89 WARN_ON(cache->reserved > 0);
90 WARN_ON(cache->reserved_pinned > 0);
96 * this adds the block group to the fs_info rb tree for the block group
99 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
100 struct btrfs_block_group_cache *block_group)
103 struct rb_node *parent = NULL;
104 struct btrfs_block_group_cache *cache;
106 spin_lock(&info->block_group_cache_lock);
107 p = &info->block_group_cache_tree.rb_node;
111 cache = rb_entry(parent, struct btrfs_block_group_cache,
113 if (block_group->key.objectid < cache->key.objectid) {
115 } else if (block_group->key.objectid > cache->key.objectid) {
118 spin_unlock(&info->block_group_cache_lock);
123 rb_link_node(&block_group->cache_node, parent, p);
124 rb_insert_color(&block_group->cache_node,
125 &info->block_group_cache_tree);
126 spin_unlock(&info->block_group_cache_lock);
132 * This will return the block group at or after bytenr if contains is 0, else
133 * it will return the block group that contains the bytenr
135 static struct btrfs_block_group_cache *
136 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
139 struct btrfs_block_group_cache *cache, *ret = NULL;
143 spin_lock(&info->block_group_cache_lock);
144 n = info->block_group_cache_tree.rb_node;
147 cache = rb_entry(n, struct btrfs_block_group_cache,
149 end = cache->key.objectid + cache->key.offset - 1;
150 start = cache->key.objectid;
152 if (bytenr < start) {
153 if (!contains && (!ret || start < ret->key.objectid))
156 } else if (bytenr > start) {
157 if (contains && bytenr <= end) {
168 btrfs_get_block_group(ret);
169 spin_unlock(&info->block_group_cache_lock);
174 static int add_excluded_extent(struct btrfs_root *root,
175 u64 start, u64 num_bytes)
177 u64 end = start + num_bytes - 1;
178 set_extent_bits(&root->fs_info->freed_extents[0],
179 start, end, EXTENT_UPTODATE, GFP_NOFS);
180 set_extent_bits(&root->fs_info->freed_extents[1],
181 start, end, EXTENT_UPTODATE, GFP_NOFS);
185 static void free_excluded_extents(struct btrfs_root *root,
186 struct btrfs_block_group_cache *cache)
190 start = cache->key.objectid;
191 end = start + cache->key.offset - 1;
193 clear_extent_bits(&root->fs_info->freed_extents[0],
194 start, end, EXTENT_UPTODATE, GFP_NOFS);
195 clear_extent_bits(&root->fs_info->freed_extents[1],
196 start, end, EXTENT_UPTODATE, GFP_NOFS);
199 static int exclude_super_stripes(struct btrfs_root *root,
200 struct btrfs_block_group_cache *cache)
207 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
208 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
209 cache->bytes_super += stripe_len;
210 ret = add_excluded_extent(root, cache->key.objectid,
215 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
216 bytenr = btrfs_sb_offset(i);
217 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
218 cache->key.objectid, bytenr,
219 0, &logical, &nr, &stripe_len);
223 cache->bytes_super += stripe_len;
224 ret = add_excluded_extent(root, logical[nr],
234 static struct btrfs_caching_control *
235 get_caching_control(struct btrfs_block_group_cache *cache)
237 struct btrfs_caching_control *ctl;
239 spin_lock(&cache->lock);
240 if (cache->cached != BTRFS_CACHE_STARTED) {
241 spin_unlock(&cache->lock);
245 /* We're loading it the fast way, so we don't have a caching_ctl. */
246 if (!cache->caching_ctl) {
247 spin_unlock(&cache->lock);
251 ctl = cache->caching_ctl;
252 atomic_inc(&ctl->count);
253 spin_unlock(&cache->lock);
257 static void put_caching_control(struct btrfs_caching_control *ctl)
259 if (atomic_dec_and_test(&ctl->count))
264 * this is only called by cache_block_group, since we could have freed extents
265 * we need to check the pinned_extents for any extents that can't be used yet
266 * since their free space will be released as soon as the transaction commits.
268 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
269 struct btrfs_fs_info *info, u64 start, u64 end)
271 u64 extent_start, extent_end, size, total_added = 0;
274 while (start < end) {
275 ret = find_first_extent_bit(info->pinned_extents, start,
276 &extent_start, &extent_end,
277 EXTENT_DIRTY | EXTENT_UPTODATE);
281 if (extent_start <= start) {
282 start = extent_end + 1;
283 } else if (extent_start > start && extent_start < end) {
284 size = extent_start - start;
286 ret = btrfs_add_free_space(block_group, start,
289 start = extent_end + 1;
298 ret = btrfs_add_free_space(block_group, start, size);
305 static int caching_kthread(void *data)
307 struct btrfs_block_group_cache *block_group = data;
308 struct btrfs_fs_info *fs_info = block_group->fs_info;
309 struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
310 struct btrfs_root *extent_root = fs_info->extent_root;
311 struct btrfs_path *path;
312 struct extent_buffer *leaf;
313 struct btrfs_key key;
319 path = btrfs_alloc_path();
323 exclude_super_stripes(extent_root, block_group);
324 spin_lock(&block_group->space_info->lock);
325 block_group->space_info->bytes_readonly += block_group->bytes_super;
326 spin_unlock(&block_group->space_info->lock);
328 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
331 * We don't want to deadlock with somebody trying to allocate a new
332 * extent for the extent root while also trying to search the extent
333 * root to add free space. So we skip locking and search the commit
334 * root, since its read-only
336 path->skip_locking = 1;
337 path->search_commit_root = 1;
342 key.type = BTRFS_EXTENT_ITEM_KEY;
344 mutex_lock(&caching_ctl->mutex);
345 /* need to make sure the commit_root doesn't disappear */
346 down_read(&fs_info->extent_commit_sem);
348 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
352 leaf = path->nodes[0];
353 nritems = btrfs_header_nritems(leaf);
357 if (fs_info->closing > 1) {
362 if (path->slots[0] < nritems) {
363 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
365 ret = find_next_key(path, 0, &key);
369 caching_ctl->progress = last;
370 btrfs_release_path(extent_root, path);
371 up_read(&fs_info->extent_commit_sem);
372 mutex_unlock(&caching_ctl->mutex);
373 if (btrfs_transaction_in_commit(fs_info))
380 if (key.objectid < block_group->key.objectid) {
385 if (key.objectid >= block_group->key.objectid +
386 block_group->key.offset)
389 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
390 total_found += add_new_free_space(block_group,
393 last = key.objectid + key.offset;
395 if (total_found > (1024 * 1024 * 2)) {
397 wake_up(&caching_ctl->wait);
404 total_found += add_new_free_space(block_group, fs_info, last,
405 block_group->key.objectid +
406 block_group->key.offset);
407 caching_ctl->progress = (u64)-1;
409 spin_lock(&block_group->lock);
410 block_group->caching_ctl = NULL;
411 block_group->cached = BTRFS_CACHE_FINISHED;
412 spin_unlock(&block_group->lock);
415 btrfs_free_path(path);
416 up_read(&fs_info->extent_commit_sem);
418 free_excluded_extents(extent_root, block_group);
420 mutex_unlock(&caching_ctl->mutex);
421 wake_up(&caching_ctl->wait);
423 put_caching_control(caching_ctl);
424 atomic_dec(&block_group->space_info->caching_threads);
425 btrfs_put_block_group(block_group);
430 static int cache_block_group(struct btrfs_block_group_cache *cache,
431 struct btrfs_trans_handle *trans,
434 struct btrfs_fs_info *fs_info = cache->fs_info;
435 struct btrfs_caching_control *caching_ctl;
436 struct task_struct *tsk;
440 if (cache->cached != BTRFS_CACHE_NO)
444 * We can't do the read from on-disk cache during a commit since we need
445 * to have the normal tree locking.
447 if (!trans->transaction->in_commit) {
448 spin_lock(&cache->lock);
449 if (cache->cached != BTRFS_CACHE_NO) {
450 spin_unlock(&cache->lock);
453 cache->cached = BTRFS_CACHE_STARTED;
454 spin_unlock(&cache->lock);
456 ret = load_free_space_cache(fs_info, cache);
458 spin_lock(&cache->lock);
460 cache->cached = BTRFS_CACHE_FINISHED;
461 cache->last_byte_to_unpin = (u64)-1;
463 cache->cached = BTRFS_CACHE_NO;
465 spin_unlock(&cache->lock);
473 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
474 BUG_ON(!caching_ctl);
476 INIT_LIST_HEAD(&caching_ctl->list);
477 mutex_init(&caching_ctl->mutex);
478 init_waitqueue_head(&caching_ctl->wait);
479 caching_ctl->block_group = cache;
480 caching_ctl->progress = cache->key.objectid;
481 /* one for caching kthread, one for caching block group list */
482 atomic_set(&caching_ctl->count, 2);
484 spin_lock(&cache->lock);
485 if (cache->cached != BTRFS_CACHE_NO) {
486 spin_unlock(&cache->lock);
490 cache->caching_ctl = caching_ctl;
491 cache->cached = BTRFS_CACHE_STARTED;
492 spin_unlock(&cache->lock);
494 down_write(&fs_info->extent_commit_sem);
495 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
496 up_write(&fs_info->extent_commit_sem);
498 atomic_inc(&cache->space_info->caching_threads);
499 btrfs_get_block_group(cache);
501 tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
502 cache->key.objectid);
505 printk(KERN_ERR "error running thread %d\n", ret);
513 * return the block group that starts at or after bytenr
515 static struct btrfs_block_group_cache *
516 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
518 struct btrfs_block_group_cache *cache;
520 cache = block_group_cache_tree_search(info, bytenr, 0);
526 * return the block group that contains the given bytenr
528 struct btrfs_block_group_cache *btrfs_lookup_block_group(
529 struct btrfs_fs_info *info,
532 struct btrfs_block_group_cache *cache;
534 cache = block_group_cache_tree_search(info, bytenr, 1);
539 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
542 struct list_head *head = &info->space_info;
543 struct btrfs_space_info *found;
545 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
546 BTRFS_BLOCK_GROUP_METADATA;
549 list_for_each_entry_rcu(found, head, list) {
550 if (found->flags & flags) {
560 * after adding space to the filesystem, we need to clear the full flags
561 * on all the space infos.
563 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
565 struct list_head *head = &info->space_info;
566 struct btrfs_space_info *found;
569 list_for_each_entry_rcu(found, head, list)
574 static u64 div_factor(u64 num, int factor)
583 static u64 div_factor_fine(u64 num, int factor)
592 u64 btrfs_find_block_group(struct btrfs_root *root,
593 u64 search_start, u64 search_hint, int owner)
595 struct btrfs_block_group_cache *cache;
597 u64 last = max(search_hint, search_start);
604 cache = btrfs_lookup_first_block_group(root->fs_info, last);
608 spin_lock(&cache->lock);
609 last = cache->key.objectid + cache->key.offset;
610 used = btrfs_block_group_used(&cache->item);
612 if ((full_search || !cache->ro) &&
613 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
614 if (used + cache->pinned + cache->reserved <
615 div_factor(cache->key.offset, factor)) {
616 group_start = cache->key.objectid;
617 spin_unlock(&cache->lock);
618 btrfs_put_block_group(cache);
622 spin_unlock(&cache->lock);
623 btrfs_put_block_group(cache);
631 if (!full_search && factor < 10) {
641 /* simple helper to search for an existing extent at a given offset */
642 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
645 struct btrfs_key key;
646 struct btrfs_path *path;
648 path = btrfs_alloc_path();
650 key.objectid = start;
652 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
653 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
655 btrfs_free_path(path);
660 * helper function to lookup reference count and flags of extent.
662 * the head node for delayed ref is used to store the sum of all the
663 * reference count modifications queued up in the rbtree. the head
664 * node may also store the extent flags to set. This way you can check
665 * to see what the reference count and extent flags would be if all of
666 * the delayed refs are not processed.
668 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
669 struct btrfs_root *root, u64 bytenr,
670 u64 num_bytes, u64 *refs, u64 *flags)
672 struct btrfs_delayed_ref_head *head;
673 struct btrfs_delayed_ref_root *delayed_refs;
674 struct btrfs_path *path;
675 struct btrfs_extent_item *ei;
676 struct extent_buffer *leaf;
677 struct btrfs_key key;
683 path = btrfs_alloc_path();
687 key.objectid = bytenr;
688 key.type = BTRFS_EXTENT_ITEM_KEY;
689 key.offset = num_bytes;
691 path->skip_locking = 1;
692 path->search_commit_root = 1;
695 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
701 leaf = path->nodes[0];
702 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
703 if (item_size >= sizeof(*ei)) {
704 ei = btrfs_item_ptr(leaf, path->slots[0],
705 struct btrfs_extent_item);
706 num_refs = btrfs_extent_refs(leaf, ei);
707 extent_flags = btrfs_extent_flags(leaf, ei);
709 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
710 struct btrfs_extent_item_v0 *ei0;
711 BUG_ON(item_size != sizeof(*ei0));
712 ei0 = btrfs_item_ptr(leaf, path->slots[0],
713 struct btrfs_extent_item_v0);
714 num_refs = btrfs_extent_refs_v0(leaf, ei0);
715 /* FIXME: this isn't correct for data */
716 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
721 BUG_ON(num_refs == 0);
731 delayed_refs = &trans->transaction->delayed_refs;
732 spin_lock(&delayed_refs->lock);
733 head = btrfs_find_delayed_ref_head(trans, bytenr);
735 if (!mutex_trylock(&head->mutex)) {
736 atomic_inc(&head->node.refs);
737 spin_unlock(&delayed_refs->lock);
739 btrfs_release_path(root->fs_info->extent_root, path);
741 mutex_lock(&head->mutex);
742 mutex_unlock(&head->mutex);
743 btrfs_put_delayed_ref(&head->node);
746 if (head->extent_op && head->extent_op->update_flags)
747 extent_flags |= head->extent_op->flags_to_set;
749 BUG_ON(num_refs == 0);
751 num_refs += head->node.ref_mod;
752 mutex_unlock(&head->mutex);
754 spin_unlock(&delayed_refs->lock);
756 WARN_ON(num_refs == 0);
760 *flags = extent_flags;
762 btrfs_free_path(path);
767 * Back reference rules. Back refs have three main goals:
769 * 1) differentiate between all holders of references to an extent so that
770 * when a reference is dropped we can make sure it was a valid reference
771 * before freeing the extent.
773 * 2) Provide enough information to quickly find the holders of an extent
774 * if we notice a given block is corrupted or bad.
776 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
777 * maintenance. This is actually the same as #2, but with a slightly
778 * different use case.
780 * There are two kinds of back refs. The implicit back refs is optimized
781 * for pointers in non-shared tree blocks. For a given pointer in a block,
782 * back refs of this kind provide information about the block's owner tree
783 * and the pointer's key. These information allow us to find the block by
784 * b-tree searching. The full back refs is for pointers in tree blocks not
785 * referenced by their owner trees. The location of tree block is recorded
786 * in the back refs. Actually the full back refs is generic, and can be
787 * used in all cases the implicit back refs is used. The major shortcoming
788 * of the full back refs is its overhead. Every time a tree block gets
789 * COWed, we have to update back refs entry for all pointers in it.
791 * For a newly allocated tree block, we use implicit back refs for
792 * pointers in it. This means most tree related operations only involve
793 * implicit back refs. For a tree block created in old transaction, the
794 * only way to drop a reference to it is COW it. So we can detect the
795 * event that tree block loses its owner tree's reference and do the
796 * back refs conversion.
798 * When a tree block is COW'd through a tree, there are four cases:
800 * The reference count of the block is one and the tree is the block's
801 * owner tree. Nothing to do in this case.
803 * The reference count of the block is one and the tree is not the
804 * block's owner tree. In this case, full back refs is used for pointers
805 * in the block. Remove these full back refs, add implicit back refs for
806 * every pointers in the new block.
808 * The reference count of the block is greater than one and the tree is
809 * the block's owner tree. In this case, implicit back refs is used for
810 * pointers in the block. Add full back refs for every pointers in the
811 * block, increase lower level extents' reference counts. The original
812 * implicit back refs are entailed to the new block.
814 * The reference count of the block is greater than one and the tree is
815 * not the block's owner tree. Add implicit back refs for every pointer in
816 * the new block, increase lower level extents' reference count.
818 * Back Reference Key composing:
820 * The key objectid corresponds to the first byte in the extent,
821 * The key type is used to differentiate between types of back refs.
822 * There are different meanings of the key offset for different types
825 * File extents can be referenced by:
827 * - multiple snapshots, subvolumes, or different generations in one subvol
828 * - different files inside a single subvolume
829 * - different offsets inside a file (bookend extents in file.c)
831 * The extent ref structure for the implicit back refs has fields for:
833 * - Objectid of the subvolume root
834 * - objectid of the file holding the reference
835 * - original offset in the file
836 * - how many bookend extents
838 * The key offset for the implicit back refs is hash of the first
841 * The extent ref structure for the full back refs has field for:
843 * - number of pointers in the tree leaf
845 * The key offset for the implicit back refs is the first byte of
848 * When a file extent is allocated, The implicit back refs is used.
849 * the fields are filled in:
851 * (root_key.objectid, inode objectid, offset in file, 1)
853 * When a file extent is removed file truncation, we find the
854 * corresponding implicit back refs and check the following fields:
856 * (btrfs_header_owner(leaf), inode objectid, offset in file)
858 * Btree extents can be referenced by:
860 * - Different subvolumes
862 * Both the implicit back refs and the full back refs for tree blocks
863 * only consist of key. The key offset for the implicit back refs is
864 * objectid of block's owner tree. The key offset for the full back refs
865 * is the first byte of parent block.
867 * When implicit back refs is used, information about the lowest key and
868 * level of the tree block are required. These information are stored in
869 * tree block info structure.
872 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
873 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
874 struct btrfs_root *root,
875 struct btrfs_path *path,
876 u64 owner, u32 extra_size)
878 struct btrfs_extent_item *item;
879 struct btrfs_extent_item_v0 *ei0;
880 struct btrfs_extent_ref_v0 *ref0;
881 struct btrfs_tree_block_info *bi;
882 struct extent_buffer *leaf;
883 struct btrfs_key key;
884 struct btrfs_key found_key;
885 u32 new_size = sizeof(*item);
889 leaf = path->nodes[0];
890 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
892 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
893 ei0 = btrfs_item_ptr(leaf, path->slots[0],
894 struct btrfs_extent_item_v0);
895 refs = btrfs_extent_refs_v0(leaf, ei0);
897 if (owner == (u64)-1) {
899 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
900 ret = btrfs_next_leaf(root, path);
904 leaf = path->nodes[0];
906 btrfs_item_key_to_cpu(leaf, &found_key,
908 BUG_ON(key.objectid != found_key.objectid);
909 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
913 ref0 = btrfs_item_ptr(leaf, path->slots[0],
914 struct btrfs_extent_ref_v0);
915 owner = btrfs_ref_objectid_v0(leaf, ref0);
919 btrfs_release_path(root, path);
921 if (owner < BTRFS_FIRST_FREE_OBJECTID)
922 new_size += sizeof(*bi);
924 new_size -= sizeof(*ei0);
925 ret = btrfs_search_slot(trans, root, &key, path,
926 new_size + extra_size, 1);
931 ret = btrfs_extend_item(trans, root, path, new_size);
934 leaf = path->nodes[0];
935 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
936 btrfs_set_extent_refs(leaf, item, refs);
937 /* FIXME: get real generation */
938 btrfs_set_extent_generation(leaf, item, 0);
939 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
940 btrfs_set_extent_flags(leaf, item,
941 BTRFS_EXTENT_FLAG_TREE_BLOCK |
942 BTRFS_BLOCK_FLAG_FULL_BACKREF);
943 bi = (struct btrfs_tree_block_info *)(item + 1);
944 /* FIXME: get first key of the block */
945 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
946 btrfs_set_tree_block_level(leaf, bi, (int)owner);
948 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
950 btrfs_mark_buffer_dirty(leaf);
955 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
957 u32 high_crc = ~(u32)0;
958 u32 low_crc = ~(u32)0;
961 lenum = cpu_to_le64(root_objectid);
962 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
963 lenum = cpu_to_le64(owner);
964 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
965 lenum = cpu_to_le64(offset);
966 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
968 return ((u64)high_crc << 31) ^ (u64)low_crc;
971 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
972 struct btrfs_extent_data_ref *ref)
974 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
975 btrfs_extent_data_ref_objectid(leaf, ref),
976 btrfs_extent_data_ref_offset(leaf, ref));
979 static int match_extent_data_ref(struct extent_buffer *leaf,
980 struct btrfs_extent_data_ref *ref,
981 u64 root_objectid, u64 owner, u64 offset)
983 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
984 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
985 btrfs_extent_data_ref_offset(leaf, ref) != offset)
990 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
991 struct btrfs_root *root,
992 struct btrfs_path *path,
993 u64 bytenr, u64 parent,
995 u64 owner, u64 offset)
997 struct btrfs_key key;
998 struct btrfs_extent_data_ref *ref;
999 struct extent_buffer *leaf;
1005 key.objectid = bytenr;
1007 key.type = BTRFS_SHARED_DATA_REF_KEY;
1008 key.offset = parent;
1010 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1011 key.offset = hash_extent_data_ref(root_objectid,
1016 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1025 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1026 key.type = BTRFS_EXTENT_REF_V0_KEY;
1027 btrfs_release_path(root, path);
1028 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1039 leaf = path->nodes[0];
1040 nritems = btrfs_header_nritems(leaf);
1042 if (path->slots[0] >= nritems) {
1043 ret = btrfs_next_leaf(root, path);
1049 leaf = path->nodes[0];
1050 nritems = btrfs_header_nritems(leaf);
1054 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1055 if (key.objectid != bytenr ||
1056 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1059 ref = btrfs_item_ptr(leaf, path->slots[0],
1060 struct btrfs_extent_data_ref);
1062 if (match_extent_data_ref(leaf, ref, root_objectid,
1065 btrfs_release_path(root, path);
1077 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1078 struct btrfs_root *root,
1079 struct btrfs_path *path,
1080 u64 bytenr, u64 parent,
1081 u64 root_objectid, u64 owner,
1082 u64 offset, int refs_to_add)
1084 struct btrfs_key key;
1085 struct extent_buffer *leaf;
1090 key.objectid = bytenr;
1092 key.type = BTRFS_SHARED_DATA_REF_KEY;
1093 key.offset = parent;
1094 size = sizeof(struct btrfs_shared_data_ref);
1096 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1097 key.offset = hash_extent_data_ref(root_objectid,
1099 size = sizeof(struct btrfs_extent_data_ref);
1102 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1103 if (ret && ret != -EEXIST)
1106 leaf = path->nodes[0];
1108 struct btrfs_shared_data_ref *ref;
1109 ref = btrfs_item_ptr(leaf, path->slots[0],
1110 struct btrfs_shared_data_ref);
1112 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1114 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1115 num_refs += refs_to_add;
1116 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1119 struct btrfs_extent_data_ref *ref;
1120 while (ret == -EEXIST) {
1121 ref = btrfs_item_ptr(leaf, path->slots[0],
1122 struct btrfs_extent_data_ref);
1123 if (match_extent_data_ref(leaf, ref, root_objectid,
1126 btrfs_release_path(root, path);
1128 ret = btrfs_insert_empty_item(trans, root, path, &key,
1130 if (ret && ret != -EEXIST)
1133 leaf = path->nodes[0];
1135 ref = btrfs_item_ptr(leaf, path->slots[0],
1136 struct btrfs_extent_data_ref);
1138 btrfs_set_extent_data_ref_root(leaf, ref,
1140 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1141 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1142 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1144 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1145 num_refs += refs_to_add;
1146 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1149 btrfs_mark_buffer_dirty(leaf);
1152 btrfs_release_path(root, path);
1156 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1157 struct btrfs_root *root,
1158 struct btrfs_path *path,
1161 struct btrfs_key key;
1162 struct btrfs_extent_data_ref *ref1 = NULL;
1163 struct btrfs_shared_data_ref *ref2 = NULL;
1164 struct extent_buffer *leaf;
1168 leaf = path->nodes[0];
1169 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1171 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1172 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1173 struct btrfs_extent_data_ref);
1174 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1175 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1176 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1177 struct btrfs_shared_data_ref);
1178 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1179 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1180 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1181 struct btrfs_extent_ref_v0 *ref0;
1182 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1183 struct btrfs_extent_ref_v0);
1184 num_refs = btrfs_ref_count_v0(leaf, ref0);
1190 BUG_ON(num_refs < refs_to_drop);
1191 num_refs -= refs_to_drop;
1193 if (num_refs == 0) {
1194 ret = btrfs_del_item(trans, root, path);
1196 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1197 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1198 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1199 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1200 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1202 struct btrfs_extent_ref_v0 *ref0;
1203 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1204 struct btrfs_extent_ref_v0);
1205 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1208 btrfs_mark_buffer_dirty(leaf);
1213 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1214 struct btrfs_path *path,
1215 struct btrfs_extent_inline_ref *iref)
1217 struct btrfs_key key;
1218 struct extent_buffer *leaf;
1219 struct btrfs_extent_data_ref *ref1;
1220 struct btrfs_shared_data_ref *ref2;
1223 leaf = path->nodes[0];
1224 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1226 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1227 BTRFS_EXTENT_DATA_REF_KEY) {
1228 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1229 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1231 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1232 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1234 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1235 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1236 struct btrfs_extent_data_ref);
1237 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1238 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1239 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1240 struct btrfs_shared_data_ref);
1241 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1242 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1243 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1244 struct btrfs_extent_ref_v0 *ref0;
1245 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1246 struct btrfs_extent_ref_v0);
1247 num_refs = btrfs_ref_count_v0(leaf, ref0);
1255 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1256 struct btrfs_root *root,
1257 struct btrfs_path *path,
1258 u64 bytenr, u64 parent,
1261 struct btrfs_key key;
1264 key.objectid = bytenr;
1266 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1267 key.offset = parent;
1269 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1270 key.offset = root_objectid;
1273 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1276 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1277 if (ret == -ENOENT && parent) {
1278 btrfs_release_path(root, path);
1279 key.type = BTRFS_EXTENT_REF_V0_KEY;
1280 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1288 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1289 struct btrfs_root *root,
1290 struct btrfs_path *path,
1291 u64 bytenr, u64 parent,
1294 struct btrfs_key key;
1297 key.objectid = bytenr;
1299 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1300 key.offset = parent;
1302 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1303 key.offset = root_objectid;
1306 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1307 btrfs_release_path(root, path);
1311 static inline int extent_ref_type(u64 parent, u64 owner)
1314 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1316 type = BTRFS_SHARED_BLOCK_REF_KEY;
1318 type = BTRFS_TREE_BLOCK_REF_KEY;
1321 type = BTRFS_SHARED_DATA_REF_KEY;
1323 type = BTRFS_EXTENT_DATA_REF_KEY;
1328 static int find_next_key(struct btrfs_path *path, int level,
1329 struct btrfs_key *key)
1332 for (; level < BTRFS_MAX_LEVEL; level++) {
1333 if (!path->nodes[level])
1335 if (path->slots[level] + 1 >=
1336 btrfs_header_nritems(path->nodes[level]))
1339 btrfs_item_key_to_cpu(path->nodes[level], key,
1340 path->slots[level] + 1);
1342 btrfs_node_key_to_cpu(path->nodes[level], key,
1343 path->slots[level] + 1);
1350 * look for inline back ref. if back ref is found, *ref_ret is set
1351 * to the address of inline back ref, and 0 is returned.
1353 * if back ref isn't found, *ref_ret is set to the address where it
1354 * should be inserted, and -ENOENT is returned.
1356 * if insert is true and there are too many inline back refs, the path
1357 * points to the extent item, and -EAGAIN is returned.
1359 * NOTE: inline back refs are ordered in the same way that back ref
1360 * items in the tree are ordered.
1362 static noinline_for_stack
1363 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1364 struct btrfs_root *root,
1365 struct btrfs_path *path,
1366 struct btrfs_extent_inline_ref **ref_ret,
1367 u64 bytenr, u64 num_bytes,
1368 u64 parent, u64 root_objectid,
1369 u64 owner, u64 offset, int insert)
1371 struct btrfs_key key;
1372 struct extent_buffer *leaf;
1373 struct btrfs_extent_item *ei;
1374 struct btrfs_extent_inline_ref *iref;
1385 key.objectid = bytenr;
1386 key.type = BTRFS_EXTENT_ITEM_KEY;
1387 key.offset = num_bytes;
1389 want = extent_ref_type(parent, owner);
1391 extra_size = btrfs_extent_inline_ref_size(want);
1392 path->keep_locks = 1;
1395 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1402 leaf = path->nodes[0];
1403 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1404 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1405 if (item_size < sizeof(*ei)) {
1410 ret = convert_extent_item_v0(trans, root, path, owner,
1416 leaf = path->nodes[0];
1417 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1420 BUG_ON(item_size < sizeof(*ei));
1422 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1423 flags = btrfs_extent_flags(leaf, ei);
1425 ptr = (unsigned long)(ei + 1);
1426 end = (unsigned long)ei + item_size;
1428 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1429 ptr += sizeof(struct btrfs_tree_block_info);
1432 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1441 iref = (struct btrfs_extent_inline_ref *)ptr;
1442 type = btrfs_extent_inline_ref_type(leaf, iref);
1446 ptr += btrfs_extent_inline_ref_size(type);
1450 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1451 struct btrfs_extent_data_ref *dref;
1452 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1453 if (match_extent_data_ref(leaf, dref, root_objectid,
1458 if (hash_extent_data_ref_item(leaf, dref) <
1459 hash_extent_data_ref(root_objectid, owner, offset))
1463 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1465 if (parent == ref_offset) {
1469 if (ref_offset < parent)
1472 if (root_objectid == ref_offset) {
1476 if (ref_offset < root_objectid)
1480 ptr += btrfs_extent_inline_ref_size(type);
1482 if (err == -ENOENT && insert) {
1483 if (item_size + extra_size >=
1484 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1489 * To add new inline back ref, we have to make sure
1490 * there is no corresponding back ref item.
1491 * For simplicity, we just do not add new inline back
1492 * ref if there is any kind of item for this block
1494 if (find_next_key(path, 0, &key) == 0 &&
1495 key.objectid == bytenr &&
1496 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1501 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1504 path->keep_locks = 0;
1505 btrfs_unlock_up_safe(path, 1);
1511 * helper to add new inline back ref
1513 static noinline_for_stack
1514 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1515 struct btrfs_root *root,
1516 struct btrfs_path *path,
1517 struct btrfs_extent_inline_ref *iref,
1518 u64 parent, u64 root_objectid,
1519 u64 owner, u64 offset, int refs_to_add,
1520 struct btrfs_delayed_extent_op *extent_op)
1522 struct extent_buffer *leaf;
1523 struct btrfs_extent_item *ei;
1526 unsigned long item_offset;
1532 leaf = path->nodes[0];
1533 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1534 item_offset = (unsigned long)iref - (unsigned long)ei;
1536 type = extent_ref_type(parent, owner);
1537 size = btrfs_extent_inline_ref_size(type);
1539 ret = btrfs_extend_item(trans, root, path, size);
1542 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1543 refs = btrfs_extent_refs(leaf, ei);
1544 refs += refs_to_add;
1545 btrfs_set_extent_refs(leaf, ei, refs);
1547 __run_delayed_extent_op(extent_op, leaf, ei);
1549 ptr = (unsigned long)ei + item_offset;
1550 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1551 if (ptr < end - size)
1552 memmove_extent_buffer(leaf, ptr + size, ptr,
1555 iref = (struct btrfs_extent_inline_ref *)ptr;
1556 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1557 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1558 struct btrfs_extent_data_ref *dref;
1559 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1560 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1561 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1562 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1563 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1564 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1565 struct btrfs_shared_data_ref *sref;
1566 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1567 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1568 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1569 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1570 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1572 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1574 btrfs_mark_buffer_dirty(leaf);
1578 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1579 struct btrfs_root *root,
1580 struct btrfs_path *path,
1581 struct btrfs_extent_inline_ref **ref_ret,
1582 u64 bytenr, u64 num_bytes, u64 parent,
1583 u64 root_objectid, u64 owner, u64 offset)
1587 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1588 bytenr, num_bytes, parent,
1589 root_objectid, owner, offset, 0);
1593 btrfs_release_path(root, path);
1596 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1597 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1600 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1601 root_objectid, owner, offset);
1607 * helper to update/remove inline back ref
1609 static noinline_for_stack
1610 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1611 struct btrfs_root *root,
1612 struct btrfs_path *path,
1613 struct btrfs_extent_inline_ref *iref,
1615 struct btrfs_delayed_extent_op *extent_op)
1617 struct extent_buffer *leaf;
1618 struct btrfs_extent_item *ei;
1619 struct btrfs_extent_data_ref *dref = NULL;
1620 struct btrfs_shared_data_ref *sref = NULL;
1629 leaf = path->nodes[0];
1630 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1631 refs = btrfs_extent_refs(leaf, ei);
1632 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1633 refs += refs_to_mod;
1634 btrfs_set_extent_refs(leaf, ei, refs);
1636 __run_delayed_extent_op(extent_op, leaf, ei);
1638 type = btrfs_extent_inline_ref_type(leaf, iref);
1640 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1641 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1642 refs = btrfs_extent_data_ref_count(leaf, dref);
1643 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1644 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1645 refs = btrfs_shared_data_ref_count(leaf, sref);
1648 BUG_ON(refs_to_mod != -1);
1651 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1652 refs += refs_to_mod;
1655 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1656 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1658 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1660 size = btrfs_extent_inline_ref_size(type);
1661 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1662 ptr = (unsigned long)iref;
1663 end = (unsigned long)ei + item_size;
1664 if (ptr + size < end)
1665 memmove_extent_buffer(leaf, ptr, ptr + size,
1668 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1671 btrfs_mark_buffer_dirty(leaf);
1675 static noinline_for_stack
1676 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1677 struct btrfs_root *root,
1678 struct btrfs_path *path,
1679 u64 bytenr, u64 num_bytes, u64 parent,
1680 u64 root_objectid, u64 owner,
1681 u64 offset, int refs_to_add,
1682 struct btrfs_delayed_extent_op *extent_op)
1684 struct btrfs_extent_inline_ref *iref;
1687 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1688 bytenr, num_bytes, parent,
1689 root_objectid, owner, offset, 1);
1691 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1692 ret = update_inline_extent_backref(trans, root, path, iref,
1693 refs_to_add, extent_op);
1694 } else if (ret == -ENOENT) {
1695 ret = setup_inline_extent_backref(trans, root, path, iref,
1696 parent, root_objectid,
1697 owner, offset, refs_to_add,
1703 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1704 struct btrfs_root *root,
1705 struct btrfs_path *path,
1706 u64 bytenr, u64 parent, u64 root_objectid,
1707 u64 owner, u64 offset, int refs_to_add)
1710 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1711 BUG_ON(refs_to_add != 1);
1712 ret = insert_tree_block_ref(trans, root, path, bytenr,
1713 parent, root_objectid);
1715 ret = insert_extent_data_ref(trans, root, path, bytenr,
1716 parent, root_objectid,
1717 owner, offset, refs_to_add);
1722 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1723 struct btrfs_root *root,
1724 struct btrfs_path *path,
1725 struct btrfs_extent_inline_ref *iref,
1726 int refs_to_drop, int is_data)
1730 BUG_ON(!is_data && refs_to_drop != 1);
1732 ret = update_inline_extent_backref(trans, root, path, iref,
1733 -refs_to_drop, NULL);
1734 } else if (is_data) {
1735 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1737 ret = btrfs_del_item(trans, root, path);
1742 static void btrfs_issue_discard(struct block_device *bdev,
1745 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL,
1746 BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
1749 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1753 u64 map_length = num_bytes;
1754 struct btrfs_multi_bio *multi = NULL;
1756 if (!btrfs_test_opt(root, DISCARD))
1759 /* Tell the block device(s) that the sectors can be discarded */
1760 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1761 bytenr, &map_length, &multi, 0);
1763 struct btrfs_bio_stripe *stripe = multi->stripes;
1766 if (map_length > num_bytes)
1767 map_length = num_bytes;
1769 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1770 btrfs_issue_discard(stripe->dev->bdev,
1780 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1781 struct btrfs_root *root,
1782 u64 bytenr, u64 num_bytes, u64 parent,
1783 u64 root_objectid, u64 owner, u64 offset)
1786 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1787 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1789 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1790 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1791 parent, root_objectid, (int)owner,
1792 BTRFS_ADD_DELAYED_REF, NULL);
1794 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1795 parent, root_objectid, owner, offset,
1796 BTRFS_ADD_DELAYED_REF, NULL);
1801 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1802 struct btrfs_root *root,
1803 u64 bytenr, u64 num_bytes,
1804 u64 parent, u64 root_objectid,
1805 u64 owner, u64 offset, int refs_to_add,
1806 struct btrfs_delayed_extent_op *extent_op)
1808 struct btrfs_path *path;
1809 struct extent_buffer *leaf;
1810 struct btrfs_extent_item *item;
1815 path = btrfs_alloc_path();
1820 path->leave_spinning = 1;
1821 /* this will setup the path even if it fails to insert the back ref */
1822 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1823 path, bytenr, num_bytes, parent,
1824 root_objectid, owner, offset,
1825 refs_to_add, extent_op);
1829 if (ret != -EAGAIN) {
1834 leaf = path->nodes[0];
1835 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1836 refs = btrfs_extent_refs(leaf, item);
1837 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1839 __run_delayed_extent_op(extent_op, leaf, item);
1841 btrfs_mark_buffer_dirty(leaf);
1842 btrfs_release_path(root->fs_info->extent_root, path);
1845 path->leave_spinning = 1;
1847 /* now insert the actual backref */
1848 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1849 path, bytenr, parent, root_objectid,
1850 owner, offset, refs_to_add);
1853 btrfs_free_path(path);
1857 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1858 struct btrfs_root *root,
1859 struct btrfs_delayed_ref_node *node,
1860 struct btrfs_delayed_extent_op *extent_op,
1861 int insert_reserved)
1864 struct btrfs_delayed_data_ref *ref;
1865 struct btrfs_key ins;
1870 ins.objectid = node->bytenr;
1871 ins.offset = node->num_bytes;
1872 ins.type = BTRFS_EXTENT_ITEM_KEY;
1874 ref = btrfs_delayed_node_to_data_ref(node);
1875 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1876 parent = ref->parent;
1878 ref_root = ref->root;
1880 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1882 BUG_ON(extent_op->update_key);
1883 flags |= extent_op->flags_to_set;
1885 ret = alloc_reserved_file_extent(trans, root,
1886 parent, ref_root, flags,
1887 ref->objectid, ref->offset,
1888 &ins, node->ref_mod);
1889 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1890 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1891 node->num_bytes, parent,
1892 ref_root, ref->objectid,
1893 ref->offset, node->ref_mod,
1895 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1896 ret = __btrfs_free_extent(trans, root, node->bytenr,
1897 node->num_bytes, parent,
1898 ref_root, ref->objectid,
1899 ref->offset, node->ref_mod,
1907 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1908 struct extent_buffer *leaf,
1909 struct btrfs_extent_item *ei)
1911 u64 flags = btrfs_extent_flags(leaf, ei);
1912 if (extent_op->update_flags) {
1913 flags |= extent_op->flags_to_set;
1914 btrfs_set_extent_flags(leaf, ei, flags);
1917 if (extent_op->update_key) {
1918 struct btrfs_tree_block_info *bi;
1919 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1920 bi = (struct btrfs_tree_block_info *)(ei + 1);
1921 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1925 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1926 struct btrfs_root *root,
1927 struct btrfs_delayed_ref_node *node,
1928 struct btrfs_delayed_extent_op *extent_op)
1930 struct btrfs_key key;
1931 struct btrfs_path *path;
1932 struct btrfs_extent_item *ei;
1933 struct extent_buffer *leaf;
1938 path = btrfs_alloc_path();
1942 key.objectid = node->bytenr;
1943 key.type = BTRFS_EXTENT_ITEM_KEY;
1944 key.offset = node->num_bytes;
1947 path->leave_spinning = 1;
1948 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1959 leaf = path->nodes[0];
1960 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1961 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1962 if (item_size < sizeof(*ei)) {
1963 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1969 leaf = path->nodes[0];
1970 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1973 BUG_ON(item_size < sizeof(*ei));
1974 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1975 __run_delayed_extent_op(extent_op, leaf, ei);
1977 btrfs_mark_buffer_dirty(leaf);
1979 btrfs_free_path(path);
1983 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1984 struct btrfs_root *root,
1985 struct btrfs_delayed_ref_node *node,
1986 struct btrfs_delayed_extent_op *extent_op,
1987 int insert_reserved)
1990 struct btrfs_delayed_tree_ref *ref;
1991 struct btrfs_key ins;
1995 ins.objectid = node->bytenr;
1996 ins.offset = node->num_bytes;
1997 ins.type = BTRFS_EXTENT_ITEM_KEY;
1999 ref = btrfs_delayed_node_to_tree_ref(node);
2000 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2001 parent = ref->parent;
2003 ref_root = ref->root;
2005 BUG_ON(node->ref_mod != 1);
2006 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2007 BUG_ON(!extent_op || !extent_op->update_flags ||
2008 !extent_op->update_key);
2009 ret = alloc_reserved_tree_block(trans, root,
2011 extent_op->flags_to_set,
2014 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2015 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2016 node->num_bytes, parent, ref_root,
2017 ref->level, 0, 1, extent_op);
2018 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2019 ret = __btrfs_free_extent(trans, root, node->bytenr,
2020 node->num_bytes, parent, ref_root,
2021 ref->level, 0, 1, extent_op);
2028 /* helper function to actually process a single delayed ref entry */
2029 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2030 struct btrfs_root *root,
2031 struct btrfs_delayed_ref_node *node,
2032 struct btrfs_delayed_extent_op *extent_op,
2033 int insert_reserved)
2036 if (btrfs_delayed_ref_is_head(node)) {
2037 struct btrfs_delayed_ref_head *head;
2039 * we've hit the end of the chain and we were supposed
2040 * to insert this extent into the tree. But, it got
2041 * deleted before we ever needed to insert it, so all
2042 * we have to do is clean up the accounting
2045 head = btrfs_delayed_node_to_head(node);
2046 if (insert_reserved) {
2047 btrfs_pin_extent(root, node->bytenr,
2048 node->num_bytes, 1);
2049 if (head->is_data) {
2050 ret = btrfs_del_csums(trans, root,
2056 mutex_unlock(&head->mutex);
2060 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2061 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2062 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2064 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2065 node->type == BTRFS_SHARED_DATA_REF_KEY)
2066 ret = run_delayed_data_ref(trans, root, node, extent_op,
2073 static noinline struct btrfs_delayed_ref_node *
2074 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2076 struct rb_node *node;
2077 struct btrfs_delayed_ref_node *ref;
2078 int action = BTRFS_ADD_DELAYED_REF;
2081 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2082 * this prevents ref count from going down to zero when
2083 * there still are pending delayed ref.
2085 node = rb_prev(&head->node.rb_node);
2089 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2091 if (ref->bytenr != head->node.bytenr)
2093 if (ref->action == action)
2095 node = rb_prev(node);
2097 if (action == BTRFS_ADD_DELAYED_REF) {
2098 action = BTRFS_DROP_DELAYED_REF;
2104 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2105 struct btrfs_root *root,
2106 struct list_head *cluster)
2108 struct btrfs_delayed_ref_root *delayed_refs;
2109 struct btrfs_delayed_ref_node *ref;
2110 struct btrfs_delayed_ref_head *locked_ref = NULL;
2111 struct btrfs_delayed_extent_op *extent_op;
2114 int must_insert_reserved = 0;
2116 delayed_refs = &trans->transaction->delayed_refs;
2119 /* pick a new head ref from the cluster list */
2120 if (list_empty(cluster))
2123 locked_ref = list_entry(cluster->next,
2124 struct btrfs_delayed_ref_head, cluster);
2126 /* grab the lock that says we are going to process
2127 * all the refs for this head */
2128 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2131 * we may have dropped the spin lock to get the head
2132 * mutex lock, and that might have given someone else
2133 * time to free the head. If that's true, it has been
2134 * removed from our list and we can move on.
2136 if (ret == -EAGAIN) {
2144 * record the must insert reserved flag before we
2145 * drop the spin lock.
2147 must_insert_reserved = locked_ref->must_insert_reserved;
2148 locked_ref->must_insert_reserved = 0;
2150 extent_op = locked_ref->extent_op;
2151 locked_ref->extent_op = NULL;
2154 * locked_ref is the head node, so we have to go one
2155 * node back for any delayed ref updates
2157 ref = select_delayed_ref(locked_ref);
2159 /* All delayed refs have been processed, Go ahead
2160 * and send the head node to run_one_delayed_ref,
2161 * so that any accounting fixes can happen
2163 ref = &locked_ref->node;
2165 if (extent_op && must_insert_reserved) {
2171 spin_unlock(&delayed_refs->lock);
2173 ret = run_delayed_extent_op(trans, root,
2179 spin_lock(&delayed_refs->lock);
2183 list_del_init(&locked_ref->cluster);
2188 rb_erase(&ref->rb_node, &delayed_refs->root);
2189 delayed_refs->num_entries--;
2191 spin_unlock(&delayed_refs->lock);
2193 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2194 must_insert_reserved);
2197 btrfs_put_delayed_ref(ref);
2202 spin_lock(&delayed_refs->lock);
2208 * this starts processing the delayed reference count updates and
2209 * extent insertions we have queued up so far. count can be
2210 * 0, which means to process everything in the tree at the start
2211 * of the run (but not newly added entries), or it can be some target
2212 * number you'd like to process.
2214 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2215 struct btrfs_root *root, unsigned long count)
2217 struct rb_node *node;
2218 struct btrfs_delayed_ref_root *delayed_refs;
2219 struct btrfs_delayed_ref_node *ref;
2220 struct list_head cluster;
2222 int run_all = count == (unsigned long)-1;
2225 if (root == root->fs_info->extent_root)
2226 root = root->fs_info->tree_root;
2228 delayed_refs = &trans->transaction->delayed_refs;
2229 INIT_LIST_HEAD(&cluster);
2231 spin_lock(&delayed_refs->lock);
2233 count = delayed_refs->num_entries * 2;
2237 if (!(run_all || run_most) &&
2238 delayed_refs->num_heads_ready < 64)
2242 * go find something we can process in the rbtree. We start at
2243 * the beginning of the tree, and then build a cluster
2244 * of refs to process starting at the first one we are able to
2247 ret = btrfs_find_ref_cluster(trans, &cluster,
2248 delayed_refs->run_delayed_start);
2252 ret = run_clustered_refs(trans, root, &cluster);
2255 count -= min_t(unsigned long, ret, count);
2262 node = rb_first(&delayed_refs->root);
2265 count = (unsigned long)-1;
2268 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2270 if (btrfs_delayed_ref_is_head(ref)) {
2271 struct btrfs_delayed_ref_head *head;
2273 head = btrfs_delayed_node_to_head(ref);
2274 atomic_inc(&ref->refs);
2276 spin_unlock(&delayed_refs->lock);
2277 mutex_lock(&head->mutex);
2278 mutex_unlock(&head->mutex);
2280 btrfs_put_delayed_ref(ref);
2284 node = rb_next(node);
2286 spin_unlock(&delayed_refs->lock);
2287 schedule_timeout(1);
2291 spin_unlock(&delayed_refs->lock);
2295 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2296 struct btrfs_root *root,
2297 u64 bytenr, u64 num_bytes, u64 flags,
2300 struct btrfs_delayed_extent_op *extent_op;
2303 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2307 extent_op->flags_to_set = flags;
2308 extent_op->update_flags = 1;
2309 extent_op->update_key = 0;
2310 extent_op->is_data = is_data ? 1 : 0;
2312 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2318 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2319 struct btrfs_root *root,
2320 struct btrfs_path *path,
2321 u64 objectid, u64 offset, u64 bytenr)
2323 struct btrfs_delayed_ref_head *head;
2324 struct btrfs_delayed_ref_node *ref;
2325 struct btrfs_delayed_data_ref *data_ref;
2326 struct btrfs_delayed_ref_root *delayed_refs;
2327 struct rb_node *node;
2331 delayed_refs = &trans->transaction->delayed_refs;
2332 spin_lock(&delayed_refs->lock);
2333 head = btrfs_find_delayed_ref_head(trans, bytenr);
2337 if (!mutex_trylock(&head->mutex)) {
2338 atomic_inc(&head->node.refs);
2339 spin_unlock(&delayed_refs->lock);
2341 btrfs_release_path(root->fs_info->extent_root, path);
2343 mutex_lock(&head->mutex);
2344 mutex_unlock(&head->mutex);
2345 btrfs_put_delayed_ref(&head->node);
2349 node = rb_prev(&head->node.rb_node);
2353 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2355 if (ref->bytenr != bytenr)
2359 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2362 data_ref = btrfs_delayed_node_to_data_ref(ref);
2364 node = rb_prev(node);
2366 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2367 if (ref->bytenr == bytenr)
2371 if (data_ref->root != root->root_key.objectid ||
2372 data_ref->objectid != objectid || data_ref->offset != offset)
2377 mutex_unlock(&head->mutex);
2379 spin_unlock(&delayed_refs->lock);
2383 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2384 struct btrfs_root *root,
2385 struct btrfs_path *path,
2386 u64 objectid, u64 offset, u64 bytenr)
2388 struct btrfs_root *extent_root = root->fs_info->extent_root;
2389 struct extent_buffer *leaf;
2390 struct btrfs_extent_data_ref *ref;
2391 struct btrfs_extent_inline_ref *iref;
2392 struct btrfs_extent_item *ei;
2393 struct btrfs_key key;
2397 key.objectid = bytenr;
2398 key.offset = (u64)-1;
2399 key.type = BTRFS_EXTENT_ITEM_KEY;
2401 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2407 if (path->slots[0] == 0)
2411 leaf = path->nodes[0];
2412 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2414 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2418 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2419 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2420 if (item_size < sizeof(*ei)) {
2421 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2425 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2427 if (item_size != sizeof(*ei) +
2428 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2431 if (btrfs_extent_generation(leaf, ei) <=
2432 btrfs_root_last_snapshot(&root->root_item))
2435 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2436 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2437 BTRFS_EXTENT_DATA_REF_KEY)
2440 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2441 if (btrfs_extent_refs(leaf, ei) !=
2442 btrfs_extent_data_ref_count(leaf, ref) ||
2443 btrfs_extent_data_ref_root(leaf, ref) !=
2444 root->root_key.objectid ||
2445 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2446 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2454 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2455 struct btrfs_root *root,
2456 u64 objectid, u64 offset, u64 bytenr)
2458 struct btrfs_path *path;
2462 path = btrfs_alloc_path();
2467 ret = check_committed_ref(trans, root, path, objectid,
2469 if (ret && ret != -ENOENT)
2472 ret2 = check_delayed_ref(trans, root, path, objectid,
2474 } while (ret2 == -EAGAIN);
2476 if (ret2 && ret2 != -ENOENT) {
2481 if (ret != -ENOENT || ret2 != -ENOENT)
2484 btrfs_free_path(path);
2485 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2491 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2492 struct extent_buffer *buf, u32 nr_extents)
2494 struct btrfs_key key;
2495 struct btrfs_file_extent_item *fi;
2503 if (!root->ref_cows)
2506 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2508 root_gen = root->root_key.offset;
2511 root_gen = trans->transid - 1;
2514 level = btrfs_header_level(buf);
2515 nritems = btrfs_header_nritems(buf);
2518 struct btrfs_leaf_ref *ref;
2519 struct btrfs_extent_info *info;
2521 ref = btrfs_alloc_leaf_ref(root, nr_extents);
2527 ref->root_gen = root_gen;
2528 ref->bytenr = buf->start;
2529 ref->owner = btrfs_header_owner(buf);
2530 ref->generation = btrfs_header_generation(buf);
2531 ref->nritems = nr_extents;
2532 info = ref->extents;
2534 for (i = 0; nr_extents > 0 && i < nritems; i++) {
2536 btrfs_item_key_to_cpu(buf, &key, i);
2537 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2539 fi = btrfs_item_ptr(buf, i,
2540 struct btrfs_file_extent_item);
2541 if (btrfs_file_extent_type(buf, fi) ==
2542 BTRFS_FILE_EXTENT_INLINE)
2544 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2545 if (disk_bytenr == 0)
2548 info->bytenr = disk_bytenr;
2550 btrfs_file_extent_disk_num_bytes(buf, fi);
2551 info->objectid = key.objectid;
2552 info->offset = key.offset;
2556 ret = btrfs_add_leaf_ref(root, ref, shared);
2557 if (ret == -EEXIST && shared) {
2558 struct btrfs_leaf_ref *old;
2559 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2561 btrfs_remove_leaf_ref(root, old);
2562 btrfs_free_leaf_ref(root, old);
2563 ret = btrfs_add_leaf_ref(root, ref, shared);
2566 btrfs_free_leaf_ref(root, ref);
2572 /* when a block goes through cow, we update the reference counts of
2573 * everything that block points to. The internal pointers of the block
2574 * can be in just about any order, and it is likely to have clusters of
2575 * things that are close together and clusters of things that are not.
2577 * To help reduce the seeks that come with updating all of these reference
2578 * counts, sort them by byte number before actual updates are done.
2580 * struct refsort is used to match byte number to slot in the btree block.
2581 * we sort based on the byte number and then use the slot to actually
2584 * struct refsort is smaller than strcut btrfs_item and smaller than
2585 * struct btrfs_key_ptr. Since we're currently limited to the page size
2586 * for a btree block, there's no way for a kmalloc of refsorts for a
2587 * single node to be bigger than a page.
2595 * for passing into sort()
2597 static int refsort_cmp(const void *a_void, const void *b_void)
2599 const struct refsort *a = a_void;
2600 const struct refsort *b = b_void;
2602 if (a->bytenr < b->bytenr)
2604 if (a->bytenr > b->bytenr)
2610 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2611 struct btrfs_root *root,
2612 struct extent_buffer *buf,
2613 int full_backref, int inc)
2620 struct btrfs_key key;
2621 struct btrfs_file_extent_item *fi;
2625 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2626 u64, u64, u64, u64, u64, u64);
2628 ref_root = btrfs_header_owner(buf);
2629 nritems = btrfs_header_nritems(buf);
2630 level = btrfs_header_level(buf);
2632 if (!root->ref_cows && level == 0)
2636 process_func = btrfs_inc_extent_ref;
2638 process_func = btrfs_free_extent;
2641 parent = buf->start;
2645 for (i = 0; i < nritems; i++) {
2647 btrfs_item_key_to_cpu(buf, &key, i);
2648 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2650 fi = btrfs_item_ptr(buf, i,
2651 struct btrfs_file_extent_item);
2652 if (btrfs_file_extent_type(buf, fi) ==
2653 BTRFS_FILE_EXTENT_INLINE)
2655 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2659 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2660 key.offset -= btrfs_file_extent_offset(buf, fi);
2661 ret = process_func(trans, root, bytenr, num_bytes,
2662 parent, ref_root, key.objectid,
2667 bytenr = btrfs_node_blockptr(buf, i);
2668 num_bytes = btrfs_level_size(root, level - 1);
2669 ret = process_func(trans, root, bytenr, num_bytes,
2670 parent, ref_root, level - 1, 0);
2681 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2682 struct extent_buffer *buf, int full_backref)
2684 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2687 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2688 struct extent_buffer *buf, int full_backref)
2690 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2693 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2694 struct btrfs_root *root,
2695 struct btrfs_path *path,
2696 struct btrfs_block_group_cache *cache)
2699 struct btrfs_root *extent_root = root->fs_info->extent_root;
2701 struct extent_buffer *leaf;
2703 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2708 leaf = path->nodes[0];
2709 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2710 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2711 btrfs_mark_buffer_dirty(leaf);
2712 btrfs_release_path(extent_root, path);
2720 static struct btrfs_block_group_cache *
2721 next_block_group(struct btrfs_root *root,
2722 struct btrfs_block_group_cache *cache)
2724 struct rb_node *node;
2725 spin_lock(&root->fs_info->block_group_cache_lock);
2726 node = rb_next(&cache->cache_node);
2727 btrfs_put_block_group(cache);
2729 cache = rb_entry(node, struct btrfs_block_group_cache,
2731 btrfs_get_block_group(cache);
2734 spin_unlock(&root->fs_info->block_group_cache_lock);
2738 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2739 struct btrfs_trans_handle *trans,
2740 struct btrfs_path *path)
2742 struct btrfs_root *root = block_group->fs_info->tree_root;
2743 struct inode *inode = NULL;
2745 int dcs = BTRFS_DC_ERROR;
2751 * If this block group is smaller than 100 megs don't bother caching the
2754 if (block_group->key.offset < (100 * 1024 * 1024)) {
2755 spin_lock(&block_group->lock);
2756 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2757 spin_unlock(&block_group->lock);
2762 inode = lookup_free_space_inode(root, block_group, path);
2763 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2764 ret = PTR_ERR(inode);
2765 btrfs_release_path(root, path);
2769 if (IS_ERR(inode)) {
2773 if (block_group->ro)
2776 ret = create_free_space_inode(root, trans, block_group, path);
2783 * We want to set the generation to 0, that way if anything goes wrong
2784 * from here on out we know not to trust this cache when we load up next
2787 BTRFS_I(inode)->generation = 0;
2788 ret = btrfs_update_inode(trans, root, inode);
2791 if (i_size_read(inode) > 0) {
2792 ret = btrfs_truncate_free_space_cache(root, trans, path,
2798 spin_lock(&block_group->lock);
2799 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2800 /* We're not cached, don't bother trying to write stuff out */
2801 dcs = BTRFS_DC_WRITTEN;
2802 spin_unlock(&block_group->lock);
2805 spin_unlock(&block_group->lock);
2807 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2812 * Just to make absolutely sure we have enough space, we're going to
2813 * preallocate 12 pages worth of space for each block group. In
2814 * practice we ought to use at most 8, but we need extra space so we can
2815 * add our header and have a terminator between the extents and the
2819 num_pages *= PAGE_CACHE_SIZE;
2821 ret = btrfs_check_data_free_space(inode, num_pages);
2825 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2826 num_pages, num_pages,
2829 dcs = BTRFS_DC_SETUP;
2830 btrfs_free_reserved_data_space(inode, num_pages);
2834 btrfs_release_path(root, path);
2836 spin_lock(&block_group->lock);
2837 block_group->disk_cache_state = dcs;
2838 spin_unlock(&block_group->lock);
2843 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2844 struct btrfs_root *root)
2846 struct btrfs_block_group_cache *cache;
2848 struct btrfs_path *path;
2851 path = btrfs_alloc_path();
2857 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2859 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2861 cache = next_block_group(root, cache);
2869 err = cache_save_setup(cache, trans, path);
2870 last = cache->key.objectid + cache->key.offset;
2871 btrfs_put_block_group(cache);
2876 err = btrfs_run_delayed_refs(trans, root,
2881 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2883 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2884 btrfs_put_block_group(cache);
2890 cache = next_block_group(root, cache);
2899 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2900 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2902 last = cache->key.objectid + cache->key.offset;
2904 err = write_one_cache_group(trans, root, path, cache);
2906 btrfs_put_block_group(cache);
2911 * I don't think this is needed since we're just marking our
2912 * preallocated extent as written, but just in case it can't
2916 err = btrfs_run_delayed_refs(trans, root,
2921 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2924 * Really this shouldn't happen, but it could if we
2925 * couldn't write the entire preallocated extent and
2926 * splitting the extent resulted in a new block.
2929 btrfs_put_block_group(cache);
2932 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2934 cache = next_block_group(root, cache);
2943 btrfs_write_out_cache(root, trans, cache, path);
2946 * If we didn't have an error then the cache state is still
2947 * NEED_WRITE, so we can set it to WRITTEN.
2949 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2950 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2951 last = cache->key.objectid + cache->key.offset;
2952 btrfs_put_block_group(cache);
2955 btrfs_free_path(path);
2959 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2961 struct btrfs_block_group_cache *block_group;
2964 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2965 if (!block_group || block_group->ro)
2968 btrfs_put_block_group(block_group);
2972 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2973 u64 total_bytes, u64 bytes_used,
2974 struct btrfs_space_info **space_info)
2976 struct btrfs_space_info *found;
2980 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2981 BTRFS_BLOCK_GROUP_RAID10))
2986 found = __find_space_info(info, flags);
2988 spin_lock(&found->lock);
2989 found->total_bytes += total_bytes;
2990 found->disk_total += total_bytes * factor;
2991 found->bytes_used += bytes_used;
2992 found->disk_used += bytes_used * factor;
2994 spin_unlock(&found->lock);
2995 *space_info = found;
2998 found = kzalloc(sizeof(*found), GFP_NOFS);
3002 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3003 INIT_LIST_HEAD(&found->block_groups[i]);
3004 init_rwsem(&found->groups_sem);
3005 spin_lock_init(&found->lock);
3006 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
3007 BTRFS_BLOCK_GROUP_SYSTEM |
3008 BTRFS_BLOCK_GROUP_METADATA);
3009 found->total_bytes = total_bytes;
3010 found->disk_total = total_bytes * factor;
3011 found->bytes_used = bytes_used;
3012 found->disk_used = bytes_used * factor;
3013 found->bytes_pinned = 0;
3014 found->bytes_reserved = 0;
3015 found->bytes_readonly = 0;
3016 found->bytes_may_use = 0;
3018 found->force_alloc = 0;
3019 *space_info = found;
3020 list_add_rcu(&found->list, &info->space_info);
3021 atomic_set(&found->caching_threads, 0);
3025 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3027 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
3028 BTRFS_BLOCK_GROUP_RAID1 |
3029 BTRFS_BLOCK_GROUP_RAID10 |
3030 BTRFS_BLOCK_GROUP_DUP);
3032 if (flags & BTRFS_BLOCK_GROUP_DATA)
3033 fs_info->avail_data_alloc_bits |= extra_flags;
3034 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3035 fs_info->avail_metadata_alloc_bits |= extra_flags;
3036 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3037 fs_info->avail_system_alloc_bits |= extra_flags;
3041 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3043 u64 num_devices = root->fs_info->fs_devices->rw_devices;
3045 if (num_devices == 1)
3046 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3047 if (num_devices < 4)
3048 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3050 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3051 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3052 BTRFS_BLOCK_GROUP_RAID10))) {
3053 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3056 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3057 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3058 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3061 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3062 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3063 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3064 (flags & BTRFS_BLOCK_GROUP_DUP)))
3065 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3069 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3071 if (flags & BTRFS_BLOCK_GROUP_DATA)
3072 flags |= root->fs_info->avail_data_alloc_bits &
3073 root->fs_info->data_alloc_profile;
3074 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3075 flags |= root->fs_info->avail_system_alloc_bits &
3076 root->fs_info->system_alloc_profile;
3077 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3078 flags |= root->fs_info->avail_metadata_alloc_bits &
3079 root->fs_info->metadata_alloc_profile;
3080 return btrfs_reduce_alloc_profile(root, flags);
3083 static u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3088 flags = BTRFS_BLOCK_GROUP_DATA;
3089 else if (root == root->fs_info->chunk_root)
3090 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3092 flags = BTRFS_BLOCK_GROUP_METADATA;
3094 return get_alloc_profile(root, flags);
3097 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3099 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3100 BTRFS_BLOCK_GROUP_DATA);
3104 * This will check the space that the inode allocates from to make sure we have
3105 * enough space for bytes.
3107 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3109 struct btrfs_space_info *data_sinfo;
3110 struct btrfs_root *root = BTRFS_I(inode)->root;
3112 int ret = 0, committed = 0, alloc_chunk = 1;
3114 /* make sure bytes are sectorsize aligned */
3115 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3117 if (root == root->fs_info->tree_root) {
3122 data_sinfo = BTRFS_I(inode)->space_info;
3127 /* make sure we have enough space to handle the data first */
3128 spin_lock(&data_sinfo->lock);
3129 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3130 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3131 data_sinfo->bytes_may_use;
3133 if (used + bytes > data_sinfo->total_bytes) {
3134 struct btrfs_trans_handle *trans;
3137 * if we don't have enough free bytes in this space then we need
3138 * to alloc a new chunk.
3140 if (!data_sinfo->full && alloc_chunk) {
3143 data_sinfo->force_alloc = 1;
3144 spin_unlock(&data_sinfo->lock);
3146 alloc_target = btrfs_get_alloc_profile(root, 1);
3147 trans = btrfs_join_transaction(root, 1);
3149 return PTR_ERR(trans);
3151 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3152 bytes + 2 * 1024 * 1024,
3154 btrfs_end_transaction(trans, root);
3159 btrfs_set_inode_space_info(root, inode);
3160 data_sinfo = BTRFS_I(inode)->space_info;
3164 spin_unlock(&data_sinfo->lock);
3166 /* commit the current transaction and try again */
3167 if (!committed && !root->fs_info->open_ioctl_trans) {
3169 trans = btrfs_join_transaction(root, 1);
3171 return PTR_ERR(trans);
3172 ret = btrfs_commit_transaction(trans, root);
3178 #if 0 /* I hope we never need this code again, just in case */
3179 printk(KERN_ERR "no space left, need %llu, %llu bytes_used, "
3180 "%llu bytes_reserved, " "%llu bytes_pinned, "
3181 "%llu bytes_readonly, %llu may use %llu total\n",
3182 (unsigned long long)bytes,
3183 (unsigned long long)data_sinfo->bytes_used,
3184 (unsigned long long)data_sinfo->bytes_reserved,
3185 (unsigned long long)data_sinfo->bytes_pinned,
3186 (unsigned long long)data_sinfo->bytes_readonly,
3187 (unsigned long long)data_sinfo->bytes_may_use,
3188 (unsigned long long)data_sinfo->total_bytes);
3192 data_sinfo->bytes_may_use += bytes;
3193 BTRFS_I(inode)->reserved_bytes += bytes;
3194 spin_unlock(&data_sinfo->lock);
3200 * called when we are clearing an delalloc extent from the
3201 * inode's io_tree or there was an error for whatever reason
3202 * after calling btrfs_check_data_free_space
3204 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3206 struct btrfs_root *root = BTRFS_I(inode)->root;
3207 struct btrfs_space_info *data_sinfo;
3209 /* make sure bytes are sectorsize aligned */
3210 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3212 data_sinfo = BTRFS_I(inode)->space_info;
3213 spin_lock(&data_sinfo->lock);
3214 data_sinfo->bytes_may_use -= bytes;
3215 BTRFS_I(inode)->reserved_bytes -= bytes;
3216 spin_unlock(&data_sinfo->lock);
3219 static void force_metadata_allocation(struct btrfs_fs_info *info)
3221 struct list_head *head = &info->space_info;
3222 struct btrfs_space_info *found;
3225 list_for_each_entry_rcu(found, head, list) {
3226 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3227 found->force_alloc = 1;
3232 static int should_alloc_chunk(struct btrfs_root *root,
3233 struct btrfs_space_info *sinfo, u64 alloc_bytes)
3235 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3238 if (sinfo->bytes_used + sinfo->bytes_reserved +
3239 alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3242 if (sinfo->bytes_used + sinfo->bytes_reserved +
3243 alloc_bytes < div_factor(num_bytes, 8))
3246 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3247 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3249 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3255 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3256 struct btrfs_root *extent_root, u64 alloc_bytes,
3257 u64 flags, int force)
3259 struct btrfs_space_info *space_info;
3260 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3263 mutex_lock(&fs_info->chunk_mutex);
3265 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3267 space_info = __find_space_info(extent_root->fs_info, flags);
3269 ret = update_space_info(extent_root->fs_info, flags,
3273 BUG_ON(!space_info);
3275 spin_lock(&space_info->lock);
3276 if (space_info->force_alloc)
3278 if (space_info->full) {
3279 spin_unlock(&space_info->lock);
3283 if (!force && !should_alloc_chunk(extent_root, space_info,
3285 spin_unlock(&space_info->lock);
3288 spin_unlock(&space_info->lock);
3291 * If we have mixed data/metadata chunks we want to make sure we keep
3292 * allocating mixed chunks instead of individual chunks.
3294 if (btrfs_mixed_space_info(space_info))
3295 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3298 * if we're doing a data chunk, go ahead and make sure that
3299 * we keep a reasonable number of metadata chunks allocated in the
3302 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3303 fs_info->data_chunk_allocations++;
3304 if (!(fs_info->data_chunk_allocations %
3305 fs_info->metadata_ratio))
3306 force_metadata_allocation(fs_info);
3309 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3310 spin_lock(&space_info->lock);
3312 space_info->full = 1;
3315 space_info->force_alloc = 0;
3316 spin_unlock(&space_info->lock);
3318 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3323 * shrink metadata reservation for delalloc
3325 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3326 struct btrfs_root *root, u64 to_reclaim, int sync)
3328 struct btrfs_block_rsv *block_rsv;
3329 struct btrfs_space_info *space_info;
3334 int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3336 block_rsv = &root->fs_info->delalloc_block_rsv;
3337 space_info = block_rsv->space_info;
3340 reserved = space_info->bytes_reserved;
3345 max_reclaim = min(reserved, to_reclaim);
3348 /* have the flusher threads jump in and do some IO */
3350 nr_pages = min_t(unsigned long, nr_pages,
3351 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3352 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3354 spin_lock(&space_info->lock);
3355 if (reserved > space_info->bytes_reserved)
3356 reclaimed += reserved - space_info->bytes_reserved;
3357 reserved = space_info->bytes_reserved;
3358 spin_unlock(&space_info->lock);
3360 if (reserved == 0 || reclaimed >= max_reclaim)
3363 if (trans && trans->transaction->blocked)
3366 __set_current_state(TASK_INTERRUPTIBLE);
3367 schedule_timeout(pause);
3369 if (pause > HZ / 10)
3373 return reclaimed >= to_reclaim;
3377 * Retries tells us how many times we've called reserve_metadata_bytes. The
3378 * idea is if this is the first call (retries == 0) then we will add to our
3379 * reserved count if we can't make the allocation in order to hold our place
3380 * while we go and try and free up space. That way for retries > 1 we don't try
3381 * and add space, we just check to see if the amount of unused space is >= the
3382 * total space, meaning that our reservation is valid.
3384 * However if we don't intend to retry this reservation, pass -1 as retries so
3385 * that it short circuits this logic.
3387 static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
3388 struct btrfs_root *root,
3389 struct btrfs_block_rsv *block_rsv,
3390 u64 orig_bytes, int flush)
3392 struct btrfs_space_info *space_info = block_rsv->space_info;
3394 u64 num_bytes = orig_bytes;
3397 bool reserved = false;
3398 bool committed = false;
3405 spin_lock(&space_info->lock);
3406 unused = space_info->bytes_used + space_info->bytes_reserved +
3407 space_info->bytes_pinned + space_info->bytes_readonly +
3408 space_info->bytes_may_use;
3411 * The idea here is that we've not already over-reserved the block group
3412 * then we can go ahead and save our reservation first and then start
3413 * flushing if we need to. Otherwise if we've already overcommitted
3414 * lets start flushing stuff first and then come back and try to make
3417 if (unused <= space_info->total_bytes) {
3418 unused = space_info->total_bytes - unused;
3419 if (unused >= num_bytes) {
3421 space_info->bytes_reserved += orig_bytes;
3425 * Ok set num_bytes to orig_bytes since we aren't
3426 * overocmmitted, this way we only try and reclaim what
3429 num_bytes = orig_bytes;
3433 * Ok we're over committed, set num_bytes to the overcommitted
3434 * amount plus the amount of bytes that we need for this
3437 num_bytes = unused - space_info->total_bytes +
3438 (orig_bytes * (retries + 1));
3442 * Couldn't make our reservation, save our place so while we're trying
3443 * to reclaim space we can actually use it instead of somebody else
3444 * stealing it from us.
3446 if (ret && !reserved) {
3447 space_info->bytes_reserved += orig_bytes;
3451 spin_unlock(&space_info->lock);
3460 * We do synchronous shrinking since we don't actually unreserve
3461 * metadata until after the IO is completed.
3463 ret = shrink_delalloc(trans, root, num_bytes, 1);
3470 * So if we were overcommitted it's possible that somebody else flushed
3471 * out enough space and we simply didn't have enough space to reclaim,
3472 * so go back around and try again.
3479 spin_lock(&space_info->lock);
3481 * Not enough space to be reclaimed, don't bother committing the
3484 if (space_info->bytes_pinned < orig_bytes)
3486 spin_unlock(&space_info->lock);
3491 if (trans || committed)
3495 trans = btrfs_join_transaction(root, 1);
3498 ret = btrfs_commit_transaction(trans, root);
3507 spin_lock(&space_info->lock);
3508 space_info->bytes_reserved -= orig_bytes;
3509 spin_unlock(&space_info->lock);
3515 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3516 struct btrfs_root *root)
3518 struct btrfs_block_rsv *block_rsv;
3520 block_rsv = trans->block_rsv;
3522 block_rsv = root->block_rsv;
3525 block_rsv = &root->fs_info->empty_block_rsv;
3530 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3534 spin_lock(&block_rsv->lock);
3535 if (block_rsv->reserved >= num_bytes) {
3536 block_rsv->reserved -= num_bytes;
3537 if (block_rsv->reserved < block_rsv->size)
3538 block_rsv->full = 0;
3541 spin_unlock(&block_rsv->lock);
3545 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3546 u64 num_bytes, int update_size)
3548 spin_lock(&block_rsv->lock);
3549 block_rsv->reserved += num_bytes;
3551 block_rsv->size += num_bytes;
3552 else if (block_rsv->reserved >= block_rsv->size)
3553 block_rsv->full = 1;
3554 spin_unlock(&block_rsv->lock);
3557 void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3558 struct btrfs_block_rsv *dest, u64 num_bytes)
3560 struct btrfs_space_info *space_info = block_rsv->space_info;
3562 spin_lock(&block_rsv->lock);
3563 if (num_bytes == (u64)-1)
3564 num_bytes = block_rsv->size;
3565 block_rsv->size -= num_bytes;
3566 if (block_rsv->reserved >= block_rsv->size) {
3567 num_bytes = block_rsv->reserved - block_rsv->size;
3568 block_rsv->reserved = block_rsv->size;
3569 block_rsv->full = 1;
3573 spin_unlock(&block_rsv->lock);
3575 if (num_bytes > 0) {
3577 block_rsv_add_bytes(dest, num_bytes, 0);
3579 spin_lock(&space_info->lock);
3580 space_info->bytes_reserved -= num_bytes;
3581 spin_unlock(&space_info->lock);
3586 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3587 struct btrfs_block_rsv *dst, u64 num_bytes)
3591 ret = block_rsv_use_bytes(src, num_bytes);
3595 block_rsv_add_bytes(dst, num_bytes, 1);
3599 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3601 memset(rsv, 0, sizeof(*rsv));
3602 spin_lock_init(&rsv->lock);
3603 atomic_set(&rsv->usage, 1);
3605 INIT_LIST_HEAD(&rsv->list);
3608 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3610 struct btrfs_block_rsv *block_rsv;
3611 struct btrfs_fs_info *fs_info = root->fs_info;
3613 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3617 btrfs_init_block_rsv(block_rsv);
3618 block_rsv->space_info = __find_space_info(fs_info,
3619 BTRFS_BLOCK_GROUP_METADATA);
3623 void btrfs_free_block_rsv(struct btrfs_root *root,
3624 struct btrfs_block_rsv *rsv)
3626 if (rsv && atomic_dec_and_test(&rsv->usage)) {
3627 btrfs_block_rsv_release(root, rsv, (u64)-1);
3634 * make the block_rsv struct be able to capture freed space.
3635 * the captured space will re-add to the the block_rsv struct
3636 * after transaction commit
3638 void btrfs_add_durable_block_rsv(struct btrfs_fs_info *fs_info,
3639 struct btrfs_block_rsv *block_rsv)
3641 block_rsv->durable = 1;
3642 mutex_lock(&fs_info->durable_block_rsv_mutex);
3643 list_add_tail(&block_rsv->list, &fs_info->durable_block_rsv_list);
3644 mutex_unlock(&fs_info->durable_block_rsv_mutex);
3647 int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
3648 struct btrfs_root *root,
3649 struct btrfs_block_rsv *block_rsv,
3657 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
3659 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3666 int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
3667 struct btrfs_root *root,
3668 struct btrfs_block_rsv *block_rsv,
3669 u64 min_reserved, int min_factor)
3672 int commit_trans = 0;
3678 spin_lock(&block_rsv->lock);
3680 num_bytes = div_factor(block_rsv->size, min_factor);
3681 if (min_reserved > num_bytes)
3682 num_bytes = min_reserved;
3684 if (block_rsv->reserved >= num_bytes) {
3687 num_bytes -= block_rsv->reserved;
3688 if (block_rsv->durable &&
3689 block_rsv->freed[0] + block_rsv->freed[1] >= num_bytes)
3692 spin_unlock(&block_rsv->lock);
3696 if (block_rsv->refill_used) {
3697 ret = reserve_metadata_bytes(trans, root, block_rsv,
3700 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3709 trans = btrfs_join_transaction(root, 1);
3710 BUG_ON(IS_ERR(trans));
3711 ret = btrfs_commit_transaction(trans, root);
3716 printk(KERN_INFO"block_rsv size %llu reserved %llu freed %llu %llu\n",
3717 block_rsv->size, block_rsv->reserved,
3718 block_rsv->freed[0], block_rsv->freed[1]);
3723 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3724 struct btrfs_block_rsv *dst_rsv,
3727 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3730 void btrfs_block_rsv_release(struct btrfs_root *root,
3731 struct btrfs_block_rsv *block_rsv,
3734 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3735 if (global_rsv->full || global_rsv == block_rsv ||
3736 block_rsv->space_info != global_rsv->space_info)
3738 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3742 * helper to calculate size of global block reservation.
3743 * the desired value is sum of space used by extent tree,
3744 * checksum tree and root tree
3746 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3748 struct btrfs_space_info *sinfo;
3752 int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
3755 * per tree used space accounting can be inaccuracy, so we
3758 spin_lock(&fs_info->extent_root->accounting_lock);
3759 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item);
3760 spin_unlock(&fs_info->extent_root->accounting_lock);
3762 spin_lock(&fs_info->csum_root->accounting_lock);
3763 num_bytes += btrfs_root_used(&fs_info->csum_root->root_item);
3764 spin_unlock(&fs_info->csum_root->accounting_lock);
3766 spin_lock(&fs_info->tree_root->accounting_lock);
3767 num_bytes += btrfs_root_used(&fs_info->tree_root->root_item);
3768 spin_unlock(&fs_info->tree_root->accounting_lock);
3770 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3771 spin_lock(&sinfo->lock);
3772 data_used = sinfo->bytes_used;
3773 spin_unlock(&sinfo->lock);
3775 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3776 spin_lock(&sinfo->lock);
3777 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3779 meta_used = sinfo->bytes_used;
3780 spin_unlock(&sinfo->lock);
3782 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3784 num_bytes += div64_u64(data_used + meta_used, 50);
3786 if (num_bytes * 3 > meta_used)
3787 num_bytes = div64_u64(meta_used, 3);
3789 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3792 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3794 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3795 struct btrfs_space_info *sinfo = block_rsv->space_info;
3798 num_bytes = calc_global_metadata_size(fs_info);
3800 spin_lock(&block_rsv->lock);
3801 spin_lock(&sinfo->lock);
3803 block_rsv->size = num_bytes;
3805 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3806 sinfo->bytes_reserved + sinfo->bytes_readonly +
3807 sinfo->bytes_may_use;
3809 if (sinfo->total_bytes > num_bytes) {
3810 num_bytes = sinfo->total_bytes - num_bytes;
3811 block_rsv->reserved += num_bytes;
3812 sinfo->bytes_reserved += num_bytes;
3815 if (block_rsv->reserved >= block_rsv->size) {
3816 num_bytes = block_rsv->reserved - block_rsv->size;
3817 sinfo->bytes_reserved -= num_bytes;
3818 block_rsv->reserved = block_rsv->size;
3819 block_rsv->full = 1;
3822 printk(KERN_INFO"global block rsv size %llu reserved %llu\n",
3823 block_rsv->size, block_rsv->reserved);
3825 spin_unlock(&sinfo->lock);
3826 spin_unlock(&block_rsv->lock);
3829 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3831 struct btrfs_space_info *space_info;
3833 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3834 fs_info->chunk_block_rsv.space_info = space_info;
3835 fs_info->chunk_block_rsv.priority = 10;
3837 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3838 fs_info->global_block_rsv.space_info = space_info;
3839 fs_info->global_block_rsv.priority = 10;
3840 fs_info->global_block_rsv.refill_used = 1;
3841 fs_info->delalloc_block_rsv.space_info = space_info;
3842 fs_info->trans_block_rsv.space_info = space_info;
3843 fs_info->empty_block_rsv.space_info = space_info;
3844 fs_info->empty_block_rsv.priority = 10;
3846 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3847 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3848 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3849 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3850 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3852 btrfs_add_durable_block_rsv(fs_info, &fs_info->global_block_rsv);
3854 btrfs_add_durable_block_rsv(fs_info, &fs_info->delalloc_block_rsv);
3856 update_global_block_rsv(fs_info);
3859 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3861 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3862 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3863 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3864 WARN_ON(fs_info->trans_block_rsv.size > 0);
3865 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3866 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3867 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3870 static u64 calc_trans_metadata_size(struct btrfs_root *root, int num_items)
3872 return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3876 int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans,
3877 struct btrfs_root *root,
3883 if (num_items == 0 || root->fs_info->chunk_root == root)
3886 num_bytes = calc_trans_metadata_size(root, num_items);
3887 ret = btrfs_block_rsv_add(trans, root, &root->fs_info->trans_block_rsv,
3890 trans->bytes_reserved += num_bytes;
3891 trans->block_rsv = &root->fs_info->trans_block_rsv;
3896 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3897 struct btrfs_root *root)
3899 if (!trans->bytes_reserved)
3902 BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv);
3903 btrfs_block_rsv_release(root, trans->block_rsv,
3904 trans->bytes_reserved);
3905 trans->bytes_reserved = 0;
3908 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3909 struct inode *inode)
3911 struct btrfs_root *root = BTRFS_I(inode)->root;
3912 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3913 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3916 * one for deleting orphan item, one for updating inode and
3917 * two for calling btrfs_truncate_inode_items.
3919 * btrfs_truncate_inode_items is a delete operation, it frees
3920 * more space than it uses in most cases. So two units of
3921 * metadata space should be enough for calling it many times.
3922 * If all of the metadata space is used, we can commit
3923 * transaction and use space it freed.
3925 u64 num_bytes = calc_trans_metadata_size(root, 4);
3926 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3929 void btrfs_orphan_release_metadata(struct inode *inode)
3931 struct btrfs_root *root = BTRFS_I(inode)->root;
3932 u64 num_bytes = calc_trans_metadata_size(root, 4);
3933 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3936 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3937 struct btrfs_pending_snapshot *pending)
3939 struct btrfs_root *root = pending->root;
3940 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3941 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3943 * two for root back/forward refs, two for directory entries
3944 * and one for root of the snapshot.
3946 u64 num_bytes = calc_trans_metadata_size(root, 5);
3947 dst_rsv->space_info = src_rsv->space_info;
3948 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3951 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
3953 return num_bytes >>= 3;
3956 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
3958 struct btrfs_root *root = BTRFS_I(inode)->root;
3959 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
3964 if (btrfs_transaction_in_commit(root->fs_info))
3965 schedule_timeout(1);
3967 num_bytes = ALIGN(num_bytes, root->sectorsize);
3969 spin_lock(&BTRFS_I(inode)->accounting_lock);
3970 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
3971 if (nr_extents > BTRFS_I(inode)->reserved_extents) {
3972 nr_extents -= BTRFS_I(inode)->reserved_extents;
3973 to_reserve = calc_trans_metadata_size(root, nr_extents);
3978 spin_unlock(&BTRFS_I(inode)->accounting_lock);
3980 to_reserve += calc_csum_metadata_size(inode, num_bytes);
3981 ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
3985 spin_lock(&BTRFS_I(inode)->accounting_lock);
3986 BTRFS_I(inode)->reserved_extents += nr_extents;
3987 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
3988 spin_unlock(&BTRFS_I(inode)->accounting_lock);
3990 block_rsv_add_bytes(block_rsv, to_reserve, 1);
3992 if (block_rsv->size > 512 * 1024 * 1024)
3993 shrink_delalloc(NULL, root, to_reserve, 0);
3998 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4000 struct btrfs_root *root = BTRFS_I(inode)->root;
4004 num_bytes = ALIGN(num_bytes, root->sectorsize);
4005 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
4007 spin_lock(&BTRFS_I(inode)->accounting_lock);
4008 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
4009 if (nr_extents < BTRFS_I(inode)->reserved_extents) {
4010 nr_extents = BTRFS_I(inode)->reserved_extents - nr_extents;
4011 BTRFS_I(inode)->reserved_extents -= nr_extents;
4015 spin_unlock(&BTRFS_I(inode)->accounting_lock);
4017 to_free = calc_csum_metadata_size(inode, num_bytes);
4019 to_free += calc_trans_metadata_size(root, nr_extents);
4021 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4025 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4029 ret = btrfs_check_data_free_space(inode, num_bytes);
4033 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4035 btrfs_free_reserved_data_space(inode, num_bytes);
4042 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4044 btrfs_delalloc_release_metadata(inode, num_bytes);
4045 btrfs_free_reserved_data_space(inode, num_bytes);
4048 static int update_block_group(struct btrfs_trans_handle *trans,
4049 struct btrfs_root *root,
4050 u64 bytenr, u64 num_bytes, int alloc)
4052 struct btrfs_block_group_cache *cache = NULL;
4053 struct btrfs_fs_info *info = root->fs_info;
4054 u64 total = num_bytes;
4059 /* block accounting for super block */
4060 spin_lock(&info->delalloc_lock);
4061 old_val = btrfs_super_bytes_used(&info->super_copy);
4063 old_val += num_bytes;
4065 old_val -= num_bytes;
4066 btrfs_set_super_bytes_used(&info->super_copy, old_val);
4067 spin_unlock(&info->delalloc_lock);
4070 cache = btrfs_lookup_block_group(info, bytenr);
4073 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4074 BTRFS_BLOCK_GROUP_RAID1 |
4075 BTRFS_BLOCK_GROUP_RAID10))
4080 * If this block group has free space cache written out, we
4081 * need to make sure to load it if we are removing space. This
4082 * is because we need the unpinning stage to actually add the
4083 * space back to the block group, otherwise we will leak space.
4085 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4086 cache_block_group(cache, trans, 1);
4088 byte_in_group = bytenr - cache->key.objectid;
4089 WARN_ON(byte_in_group > cache->key.offset);
4091 spin_lock(&cache->space_info->lock);
4092 spin_lock(&cache->lock);
4094 if (btrfs_super_cache_generation(&info->super_copy) != 0 &&
4095 cache->disk_cache_state < BTRFS_DC_CLEAR)
4096 cache->disk_cache_state = BTRFS_DC_CLEAR;
4099 old_val = btrfs_block_group_used(&cache->item);
4100 num_bytes = min(total, cache->key.offset - byte_in_group);
4102 old_val += num_bytes;
4103 btrfs_set_block_group_used(&cache->item, old_val);
4104 cache->reserved -= num_bytes;
4105 cache->space_info->bytes_reserved -= num_bytes;
4106 cache->space_info->bytes_used += num_bytes;
4107 cache->space_info->disk_used += num_bytes * factor;
4108 spin_unlock(&cache->lock);
4109 spin_unlock(&cache->space_info->lock);
4111 old_val -= num_bytes;
4112 btrfs_set_block_group_used(&cache->item, old_val);
4113 cache->pinned += num_bytes;
4114 cache->space_info->bytes_pinned += num_bytes;
4115 cache->space_info->bytes_used -= num_bytes;
4116 cache->space_info->disk_used -= num_bytes * factor;
4117 spin_unlock(&cache->lock);
4118 spin_unlock(&cache->space_info->lock);
4120 set_extent_dirty(info->pinned_extents,
4121 bytenr, bytenr + num_bytes - 1,
4122 GFP_NOFS | __GFP_NOFAIL);
4124 btrfs_put_block_group(cache);
4126 bytenr += num_bytes;
4131 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4133 struct btrfs_block_group_cache *cache;
4136 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4140 bytenr = cache->key.objectid;
4141 btrfs_put_block_group(cache);
4146 static int pin_down_extent(struct btrfs_root *root,
4147 struct btrfs_block_group_cache *cache,
4148 u64 bytenr, u64 num_bytes, int reserved)
4150 spin_lock(&cache->space_info->lock);
4151 spin_lock(&cache->lock);
4152 cache->pinned += num_bytes;
4153 cache->space_info->bytes_pinned += num_bytes;
4155 cache->reserved -= num_bytes;
4156 cache->space_info->bytes_reserved -= num_bytes;
4158 spin_unlock(&cache->lock);
4159 spin_unlock(&cache->space_info->lock);
4161 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4162 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4167 * this function must be called within transaction
4169 int btrfs_pin_extent(struct btrfs_root *root,
4170 u64 bytenr, u64 num_bytes, int reserved)
4172 struct btrfs_block_group_cache *cache;
4174 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4177 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4179 btrfs_put_block_group(cache);
4184 * update size of reserved extents. this function may return -EAGAIN
4185 * if 'reserve' is true or 'sinfo' is false.
4187 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
4188 u64 num_bytes, int reserve, int sinfo)
4192 struct btrfs_space_info *space_info = cache->space_info;
4193 spin_lock(&space_info->lock);
4194 spin_lock(&cache->lock);
4199 cache->reserved += num_bytes;
4200 space_info->bytes_reserved += num_bytes;
4204 space_info->bytes_readonly += num_bytes;
4205 cache->reserved -= num_bytes;
4206 space_info->bytes_reserved -= num_bytes;
4208 spin_unlock(&cache->lock);
4209 spin_unlock(&space_info->lock);
4211 spin_lock(&cache->lock);
4216 cache->reserved += num_bytes;
4218 cache->reserved -= num_bytes;
4220 spin_unlock(&cache->lock);
4225 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4226 struct btrfs_root *root)
4228 struct btrfs_fs_info *fs_info = root->fs_info;
4229 struct btrfs_caching_control *next;
4230 struct btrfs_caching_control *caching_ctl;
4231 struct btrfs_block_group_cache *cache;
4233 down_write(&fs_info->extent_commit_sem);
4235 list_for_each_entry_safe(caching_ctl, next,
4236 &fs_info->caching_block_groups, list) {
4237 cache = caching_ctl->block_group;
4238 if (block_group_cache_done(cache)) {
4239 cache->last_byte_to_unpin = (u64)-1;
4240 list_del_init(&caching_ctl->list);
4241 put_caching_control(caching_ctl);
4243 cache->last_byte_to_unpin = caching_ctl->progress;
4247 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4248 fs_info->pinned_extents = &fs_info->freed_extents[1];
4250 fs_info->pinned_extents = &fs_info->freed_extents[0];
4252 up_write(&fs_info->extent_commit_sem);
4254 update_global_block_rsv(fs_info);
4258 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4260 struct btrfs_fs_info *fs_info = root->fs_info;
4261 struct btrfs_block_group_cache *cache = NULL;
4264 while (start <= end) {
4266 start >= cache->key.objectid + cache->key.offset) {
4268 btrfs_put_block_group(cache);
4269 cache = btrfs_lookup_block_group(fs_info, start);
4273 len = cache->key.objectid + cache->key.offset - start;
4274 len = min(len, end + 1 - start);
4276 if (start < cache->last_byte_to_unpin) {
4277 len = min(len, cache->last_byte_to_unpin - start);
4278 btrfs_add_free_space(cache, start, len);
4283 spin_lock(&cache->space_info->lock);
4284 spin_lock(&cache->lock);
4285 cache->pinned -= len;
4286 cache->space_info->bytes_pinned -= len;
4288 cache->space_info->bytes_readonly += len;
4289 } else if (cache->reserved_pinned > 0) {
4290 len = min(len, cache->reserved_pinned);
4291 cache->reserved_pinned -= len;
4292 cache->space_info->bytes_reserved += len;
4294 spin_unlock(&cache->lock);
4295 spin_unlock(&cache->space_info->lock);
4299 btrfs_put_block_group(cache);
4303 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4304 struct btrfs_root *root)
4306 struct btrfs_fs_info *fs_info = root->fs_info;
4307 struct extent_io_tree *unpin;
4308 struct btrfs_block_rsv *block_rsv;
4309 struct btrfs_block_rsv *next_rsv;
4315 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4316 unpin = &fs_info->freed_extents[1];
4318 unpin = &fs_info->freed_extents[0];
4321 ret = find_first_extent_bit(unpin, 0, &start, &end,
4326 ret = btrfs_discard_extent(root, start, end + 1 - start);
4328 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4329 unpin_extent_range(root, start, end);
4333 mutex_lock(&fs_info->durable_block_rsv_mutex);
4334 list_for_each_entry_safe(block_rsv, next_rsv,
4335 &fs_info->durable_block_rsv_list, list) {
4337 idx = trans->transid & 0x1;
4338 if (block_rsv->freed[idx] > 0) {
4339 block_rsv_add_bytes(block_rsv,
4340 block_rsv->freed[idx], 0);
4341 block_rsv->freed[idx] = 0;
4343 if (atomic_read(&block_rsv->usage) == 0) {
4344 btrfs_block_rsv_release(root, block_rsv, (u64)-1);
4346 if (block_rsv->freed[0] == 0 &&
4347 block_rsv->freed[1] == 0) {
4348 list_del_init(&block_rsv->list);
4352 btrfs_block_rsv_release(root, block_rsv, 0);
4355 mutex_unlock(&fs_info->durable_block_rsv_mutex);
4360 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4361 struct btrfs_root *root,
4362 u64 bytenr, u64 num_bytes, u64 parent,
4363 u64 root_objectid, u64 owner_objectid,
4364 u64 owner_offset, int refs_to_drop,
4365 struct btrfs_delayed_extent_op *extent_op)
4367 struct btrfs_key key;
4368 struct btrfs_path *path;
4369 struct btrfs_fs_info *info = root->fs_info;
4370 struct btrfs_root *extent_root = info->extent_root;
4371 struct extent_buffer *leaf;
4372 struct btrfs_extent_item *ei;
4373 struct btrfs_extent_inline_ref *iref;
4376 int extent_slot = 0;
4377 int found_extent = 0;
4382 path = btrfs_alloc_path();
4387 path->leave_spinning = 1;
4389 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4390 BUG_ON(!is_data && refs_to_drop != 1);
4392 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4393 bytenr, num_bytes, parent,
4394 root_objectid, owner_objectid,
4397 extent_slot = path->slots[0];
4398 while (extent_slot >= 0) {
4399 btrfs_item_key_to_cpu(path->nodes[0], &key,
4401 if (key.objectid != bytenr)
4403 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4404 key.offset == num_bytes) {
4408 if (path->slots[0] - extent_slot > 5)
4412 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4413 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4414 if (found_extent && item_size < sizeof(*ei))
4417 if (!found_extent) {
4419 ret = remove_extent_backref(trans, extent_root, path,
4423 btrfs_release_path(extent_root, path);
4424 path->leave_spinning = 1;
4426 key.objectid = bytenr;
4427 key.type = BTRFS_EXTENT_ITEM_KEY;
4428 key.offset = num_bytes;
4430 ret = btrfs_search_slot(trans, extent_root,
4433 printk(KERN_ERR "umm, got %d back from search"
4434 ", was looking for %llu\n", ret,
4435 (unsigned long long)bytenr);
4436 btrfs_print_leaf(extent_root, path->nodes[0]);
4439 extent_slot = path->slots[0];
4442 btrfs_print_leaf(extent_root, path->nodes[0]);
4444 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4445 "parent %llu root %llu owner %llu offset %llu\n",
4446 (unsigned long long)bytenr,
4447 (unsigned long long)parent,
4448 (unsigned long long)root_objectid,
4449 (unsigned long long)owner_objectid,
4450 (unsigned long long)owner_offset);
4453 leaf = path->nodes[0];
4454 item_size = btrfs_item_size_nr(leaf, extent_slot);
4455 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4456 if (item_size < sizeof(*ei)) {
4457 BUG_ON(found_extent || extent_slot != path->slots[0]);
4458 ret = convert_extent_item_v0(trans, extent_root, path,
4462 btrfs_release_path(extent_root, path);
4463 path->leave_spinning = 1;
4465 key.objectid = bytenr;
4466 key.type = BTRFS_EXTENT_ITEM_KEY;
4467 key.offset = num_bytes;
4469 ret = btrfs_search_slot(trans, extent_root, &key, path,
4472 printk(KERN_ERR "umm, got %d back from search"
4473 ", was looking for %llu\n", ret,
4474 (unsigned long long)bytenr);
4475 btrfs_print_leaf(extent_root, path->nodes[0]);
4478 extent_slot = path->slots[0];
4479 leaf = path->nodes[0];
4480 item_size = btrfs_item_size_nr(leaf, extent_slot);
4483 BUG_ON(item_size < sizeof(*ei));
4484 ei = btrfs_item_ptr(leaf, extent_slot,
4485 struct btrfs_extent_item);
4486 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4487 struct btrfs_tree_block_info *bi;
4488 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4489 bi = (struct btrfs_tree_block_info *)(ei + 1);
4490 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4493 refs = btrfs_extent_refs(leaf, ei);
4494 BUG_ON(refs < refs_to_drop);
4495 refs -= refs_to_drop;
4499 __run_delayed_extent_op(extent_op, leaf, ei);
4501 * In the case of inline back ref, reference count will
4502 * be updated by remove_extent_backref
4505 BUG_ON(!found_extent);
4507 btrfs_set_extent_refs(leaf, ei, refs);
4508 btrfs_mark_buffer_dirty(leaf);
4511 ret = remove_extent_backref(trans, extent_root, path,
4518 BUG_ON(is_data && refs_to_drop !=
4519 extent_data_ref_count(root, path, iref));
4521 BUG_ON(path->slots[0] != extent_slot);
4523 BUG_ON(path->slots[0] != extent_slot + 1);
4524 path->slots[0] = extent_slot;
4529 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4532 btrfs_release_path(extent_root, path);
4535 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4538 invalidate_mapping_pages(info->btree_inode->i_mapping,
4539 bytenr >> PAGE_CACHE_SHIFT,
4540 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4543 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4546 btrfs_free_path(path);
4551 * when we free an block, it is possible (and likely) that we free the last
4552 * delayed ref for that extent as well. This searches the delayed ref tree for
4553 * a given extent, and if there are no other delayed refs to be processed, it
4554 * removes it from the tree.
4556 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4557 struct btrfs_root *root, u64 bytenr)
4559 struct btrfs_delayed_ref_head *head;
4560 struct btrfs_delayed_ref_root *delayed_refs;
4561 struct btrfs_delayed_ref_node *ref;
4562 struct rb_node *node;
4565 delayed_refs = &trans->transaction->delayed_refs;
4566 spin_lock(&delayed_refs->lock);
4567 head = btrfs_find_delayed_ref_head(trans, bytenr);
4571 node = rb_prev(&head->node.rb_node);
4575 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4577 /* there are still entries for this ref, we can't drop it */
4578 if (ref->bytenr == bytenr)
4581 if (head->extent_op) {
4582 if (!head->must_insert_reserved)
4584 kfree(head->extent_op);
4585 head->extent_op = NULL;
4589 * waiting for the lock here would deadlock. If someone else has it
4590 * locked they are already in the process of dropping it anyway
4592 if (!mutex_trylock(&head->mutex))
4596 * at this point we have a head with no other entries. Go
4597 * ahead and process it.
4599 head->node.in_tree = 0;
4600 rb_erase(&head->node.rb_node, &delayed_refs->root);
4602 delayed_refs->num_entries--;
4605 * we don't take a ref on the node because we're removing it from the
4606 * tree, so we just steal the ref the tree was holding.
4608 delayed_refs->num_heads--;
4609 if (list_empty(&head->cluster))
4610 delayed_refs->num_heads_ready--;
4612 list_del_init(&head->cluster);
4613 spin_unlock(&delayed_refs->lock);
4615 BUG_ON(head->extent_op);
4616 if (head->must_insert_reserved)
4619 mutex_unlock(&head->mutex);
4620 btrfs_put_delayed_ref(&head->node);
4623 spin_unlock(&delayed_refs->lock);
4627 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4628 struct btrfs_root *root,
4629 struct extent_buffer *buf,
4630 u64 parent, int last_ref)
4632 struct btrfs_block_rsv *block_rsv;
4633 struct btrfs_block_group_cache *cache = NULL;
4636 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4637 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4638 parent, root->root_key.objectid,
4639 btrfs_header_level(buf),
4640 BTRFS_DROP_DELAYED_REF, NULL);
4647 block_rsv = get_block_rsv(trans, root);
4648 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4649 if (block_rsv->space_info != cache->space_info)
4652 if (btrfs_header_generation(buf) == trans->transid) {
4653 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4654 ret = check_ref_cleanup(trans, root, buf->start);
4659 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4660 pin_down_extent(root, cache, buf->start, buf->len, 1);
4664 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4666 btrfs_add_free_space(cache, buf->start, buf->len);
4667 ret = update_reserved_bytes(cache, buf->len, 0, 0);
4668 if (ret == -EAGAIN) {
4669 /* block group became read-only */
4670 update_reserved_bytes(cache, buf->len, 0, 1);
4675 spin_lock(&block_rsv->lock);
4676 if (block_rsv->reserved < block_rsv->size) {
4677 block_rsv->reserved += buf->len;
4680 spin_unlock(&block_rsv->lock);
4683 spin_lock(&cache->space_info->lock);
4684 cache->space_info->bytes_reserved -= buf->len;
4685 spin_unlock(&cache->space_info->lock);
4690 if (block_rsv->durable && !cache->ro) {
4692 spin_lock(&cache->lock);
4694 cache->reserved_pinned += buf->len;
4697 spin_unlock(&cache->lock);
4700 spin_lock(&block_rsv->lock);
4701 block_rsv->freed[trans->transid & 0x1] += buf->len;
4702 spin_unlock(&block_rsv->lock);
4706 btrfs_put_block_group(cache);
4709 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4710 struct btrfs_root *root,
4711 u64 bytenr, u64 num_bytes, u64 parent,
4712 u64 root_objectid, u64 owner, u64 offset)
4717 * tree log blocks never actually go into the extent allocation
4718 * tree, just update pinning info and exit early.
4720 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4721 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4722 /* unlocks the pinned mutex */
4723 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4725 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4726 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4727 parent, root_objectid, (int)owner,
4728 BTRFS_DROP_DELAYED_REF, NULL);
4731 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4732 parent, root_objectid, owner,
4733 offset, BTRFS_DROP_DELAYED_REF, NULL);
4739 static u64 stripe_align(struct btrfs_root *root, u64 val)
4741 u64 mask = ((u64)root->stripesize - 1);
4742 u64 ret = (val + mask) & ~mask;
4747 * when we wait for progress in the block group caching, its because
4748 * our allocation attempt failed at least once. So, we must sleep
4749 * and let some progress happen before we try again.
4751 * This function will sleep at least once waiting for new free space to
4752 * show up, and then it will check the block group free space numbers
4753 * for our min num_bytes. Another option is to have it go ahead
4754 * and look in the rbtree for a free extent of a given size, but this
4758 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4761 struct btrfs_caching_control *caching_ctl;
4764 caching_ctl = get_caching_control(cache);
4768 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4769 (cache->free_space >= num_bytes));
4771 put_caching_control(caching_ctl);
4776 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4778 struct btrfs_caching_control *caching_ctl;
4781 caching_ctl = get_caching_control(cache);
4785 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4787 put_caching_control(caching_ctl);
4791 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4794 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4796 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4798 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4800 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4807 enum btrfs_loop_type {
4808 LOOP_FIND_IDEAL = 0,
4809 LOOP_CACHING_NOWAIT = 1,
4810 LOOP_CACHING_WAIT = 2,
4811 LOOP_ALLOC_CHUNK = 3,
4812 LOOP_NO_EMPTY_SIZE = 4,
4816 * walks the btree of allocated extents and find a hole of a given size.
4817 * The key ins is changed to record the hole:
4818 * ins->objectid == block start
4819 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4820 * ins->offset == number of blocks
4821 * Any available blocks before search_start are skipped.
4823 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4824 struct btrfs_root *orig_root,
4825 u64 num_bytes, u64 empty_size,
4826 u64 search_start, u64 search_end,
4827 u64 hint_byte, struct btrfs_key *ins,
4831 struct btrfs_root *root = orig_root->fs_info->extent_root;
4832 struct btrfs_free_cluster *last_ptr = NULL;
4833 struct btrfs_block_group_cache *block_group = NULL;
4834 int empty_cluster = 2 * 1024 * 1024;
4835 int allowed_chunk_alloc = 0;
4836 int done_chunk_alloc = 0;
4837 struct btrfs_space_info *space_info;
4838 int last_ptr_loop = 0;
4841 bool found_uncached_bg = false;
4842 bool failed_cluster_refill = false;
4843 bool failed_alloc = false;
4844 bool use_cluster = true;
4845 u64 ideal_cache_percent = 0;
4846 u64 ideal_cache_offset = 0;
4848 WARN_ON(num_bytes < root->sectorsize);
4849 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4853 space_info = __find_space_info(root->fs_info, data);
4855 printk(KERN_ERR "No space info for %d\n", data);
4860 * If the space info is for both data and metadata it means we have a
4861 * small filesystem and we can't use the clustering stuff.
4863 if (btrfs_mixed_space_info(space_info))
4864 use_cluster = false;
4866 if (orig_root->ref_cows || empty_size)
4867 allowed_chunk_alloc = 1;
4869 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
4870 last_ptr = &root->fs_info->meta_alloc_cluster;
4871 if (!btrfs_test_opt(root, SSD))
4872 empty_cluster = 64 * 1024;
4875 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
4876 btrfs_test_opt(root, SSD)) {
4877 last_ptr = &root->fs_info->data_alloc_cluster;
4881 spin_lock(&last_ptr->lock);
4882 if (last_ptr->block_group)
4883 hint_byte = last_ptr->window_start;
4884 spin_unlock(&last_ptr->lock);
4887 search_start = max(search_start, first_logical_byte(root, 0));
4888 search_start = max(search_start, hint_byte);
4893 if (search_start == hint_byte) {
4895 block_group = btrfs_lookup_block_group(root->fs_info,
4898 * we don't want to use the block group if it doesn't match our
4899 * allocation bits, or if its not cached.
4901 * However if we are re-searching with an ideal block group
4902 * picked out then we don't care that the block group is cached.
4904 if (block_group && block_group_bits(block_group, data) &&
4905 (block_group->cached != BTRFS_CACHE_NO ||
4906 search_start == ideal_cache_offset)) {
4907 down_read(&space_info->groups_sem);
4908 if (list_empty(&block_group->list) ||
4911 * someone is removing this block group,
4912 * we can't jump into the have_block_group
4913 * target because our list pointers are not
4916 btrfs_put_block_group(block_group);
4917 up_read(&space_info->groups_sem);
4919 index = get_block_group_index(block_group);
4920 goto have_block_group;
4922 } else if (block_group) {
4923 btrfs_put_block_group(block_group);
4927 down_read(&space_info->groups_sem);
4928 list_for_each_entry(block_group, &space_info->block_groups[index],
4933 btrfs_get_block_group(block_group);
4934 search_start = block_group->key.objectid;
4937 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
4940 ret = cache_block_group(block_group, trans, 1);
4941 if (block_group->cached == BTRFS_CACHE_FINISHED)
4942 goto have_block_group;
4944 free_percent = btrfs_block_group_used(&block_group->item);
4945 free_percent *= 100;
4946 free_percent = div64_u64(free_percent,
4947 block_group->key.offset);
4948 free_percent = 100 - free_percent;
4949 if (free_percent > ideal_cache_percent &&
4950 likely(!block_group->ro)) {
4951 ideal_cache_offset = block_group->key.objectid;
4952 ideal_cache_percent = free_percent;
4956 * We only want to start kthread caching if we are at
4957 * the point where we will wait for caching to make
4958 * progress, or if our ideal search is over and we've
4959 * found somebody to start caching.
4961 if (loop > LOOP_CACHING_NOWAIT ||
4962 (loop > LOOP_FIND_IDEAL &&
4963 atomic_read(&space_info->caching_threads) < 2)) {
4964 ret = cache_block_group(block_group, trans, 0);
4967 found_uncached_bg = true;
4970 * If loop is set for cached only, try the next block
4973 if (loop == LOOP_FIND_IDEAL)
4977 cached = block_group_cache_done(block_group);
4978 if (unlikely(!cached))
4979 found_uncached_bg = true;
4981 if (unlikely(block_group->ro))
4985 * Ok we want to try and use the cluster allocator, so lets look
4986 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
4987 * have tried the cluster allocator plenty of times at this
4988 * point and not have found anything, so we are likely way too
4989 * fragmented for the clustering stuff to find anything, so lets
4990 * just skip it and let the allocator find whatever block it can
4993 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
4995 * the refill lock keeps out other
4996 * people trying to start a new cluster
4998 spin_lock(&last_ptr->refill_lock);
4999 if (last_ptr->block_group &&
5000 (last_ptr->block_group->ro ||
5001 !block_group_bits(last_ptr->block_group, data))) {
5003 goto refill_cluster;
5006 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5007 num_bytes, search_start);
5009 /* we have a block, we're done */
5010 spin_unlock(&last_ptr->refill_lock);
5014 spin_lock(&last_ptr->lock);
5016 * whoops, this cluster doesn't actually point to
5017 * this block group. Get a ref on the block
5018 * group is does point to and try again
5020 if (!last_ptr_loop && last_ptr->block_group &&
5021 last_ptr->block_group != block_group) {
5023 btrfs_put_block_group(block_group);
5024 block_group = last_ptr->block_group;
5025 btrfs_get_block_group(block_group);
5026 spin_unlock(&last_ptr->lock);
5027 spin_unlock(&last_ptr->refill_lock);
5030 search_start = block_group->key.objectid;
5032 * we know this block group is properly
5033 * in the list because
5034 * btrfs_remove_block_group, drops the
5035 * cluster before it removes the block
5036 * group from the list
5038 goto have_block_group;
5040 spin_unlock(&last_ptr->lock);
5043 * this cluster didn't work out, free it and
5046 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5050 /* allocate a cluster in this block group */
5051 ret = btrfs_find_space_cluster(trans, root,
5052 block_group, last_ptr,
5054 empty_cluster + empty_size);
5057 * now pull our allocation out of this
5060 offset = btrfs_alloc_from_cluster(block_group,
5061 last_ptr, num_bytes,
5064 /* we found one, proceed */
5065 spin_unlock(&last_ptr->refill_lock);
5068 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5069 && !failed_cluster_refill) {
5070 spin_unlock(&last_ptr->refill_lock);
5072 failed_cluster_refill = true;
5073 wait_block_group_cache_progress(block_group,
5074 num_bytes + empty_cluster + empty_size);
5075 goto have_block_group;
5079 * at this point we either didn't find a cluster
5080 * or we weren't able to allocate a block from our
5081 * cluster. Free the cluster we've been trying
5082 * to use, and go to the next block group
5084 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5085 spin_unlock(&last_ptr->refill_lock);
5089 offset = btrfs_find_space_for_alloc(block_group, search_start,
5090 num_bytes, empty_size);
5092 * If we didn't find a chunk, and we haven't failed on this
5093 * block group before, and this block group is in the middle of
5094 * caching and we are ok with waiting, then go ahead and wait
5095 * for progress to be made, and set failed_alloc to true.
5097 * If failed_alloc is true then we've already waited on this
5098 * block group once and should move on to the next block group.
5100 if (!offset && !failed_alloc && !cached &&
5101 loop > LOOP_CACHING_NOWAIT) {
5102 wait_block_group_cache_progress(block_group,
5103 num_bytes + empty_size);
5104 failed_alloc = true;
5105 goto have_block_group;
5106 } else if (!offset) {
5110 search_start = stripe_align(root, offset);
5111 /* move on to the next group */
5112 if (search_start + num_bytes >= search_end) {
5113 btrfs_add_free_space(block_group, offset, num_bytes);
5117 /* move on to the next group */
5118 if (search_start + num_bytes >
5119 block_group->key.objectid + block_group->key.offset) {
5120 btrfs_add_free_space(block_group, offset, num_bytes);
5124 ins->objectid = search_start;
5125 ins->offset = num_bytes;
5127 if (offset < search_start)
5128 btrfs_add_free_space(block_group, offset,
5129 search_start - offset);
5130 BUG_ON(offset > search_start);
5132 ret = update_reserved_bytes(block_group, num_bytes, 1,
5133 (data & BTRFS_BLOCK_GROUP_DATA));
5134 if (ret == -EAGAIN) {
5135 btrfs_add_free_space(block_group, offset, num_bytes);
5139 /* we are all good, lets return */
5140 ins->objectid = search_start;
5141 ins->offset = num_bytes;
5143 if (offset < search_start)
5144 btrfs_add_free_space(block_group, offset,
5145 search_start - offset);
5146 BUG_ON(offset > search_start);
5149 failed_cluster_refill = false;
5150 failed_alloc = false;
5151 BUG_ON(index != get_block_group_index(block_group));
5152 btrfs_put_block_group(block_group);
5154 up_read(&space_info->groups_sem);
5156 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5159 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5160 * for them to make caching progress. Also
5161 * determine the best possible bg to cache
5162 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5163 * caching kthreads as we move along
5164 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5165 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5166 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5169 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE &&
5170 (found_uncached_bg || empty_size || empty_cluster ||
5171 allowed_chunk_alloc)) {
5173 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5174 found_uncached_bg = false;
5176 if (!ideal_cache_percent &&
5177 atomic_read(&space_info->caching_threads))
5181 * 1 of the following 2 things have happened so far
5183 * 1) We found an ideal block group for caching that
5184 * is mostly full and will cache quickly, so we might
5185 * as well wait for it.
5187 * 2) We searched for cached only and we didn't find
5188 * anything, and we didn't start any caching kthreads
5189 * either, so chances are we will loop through and
5190 * start a couple caching kthreads, and then come back
5191 * around and just wait for them. This will be slower
5192 * because we will have 2 caching kthreads reading at
5193 * the same time when we could have just started one
5194 * and waited for it to get far enough to give us an
5195 * allocation, so go ahead and go to the wait caching
5198 loop = LOOP_CACHING_WAIT;
5199 search_start = ideal_cache_offset;
5200 ideal_cache_percent = 0;
5202 } else if (loop == LOOP_FIND_IDEAL) {
5204 * Didn't find a uncached bg, wait on anything we find
5207 loop = LOOP_CACHING_WAIT;
5211 if (loop < LOOP_CACHING_WAIT) {
5216 if (loop == LOOP_ALLOC_CHUNK) {
5221 if (allowed_chunk_alloc) {
5222 ret = do_chunk_alloc(trans, root, num_bytes +
5223 2 * 1024 * 1024, data, 1);
5224 allowed_chunk_alloc = 0;
5225 done_chunk_alloc = 1;
5226 } else if (!done_chunk_alloc) {
5227 space_info->force_alloc = 1;
5230 if (loop < LOOP_NO_EMPTY_SIZE) {
5235 } else if (!ins->objectid) {
5239 /* we found what we needed */
5240 if (ins->objectid) {
5241 if (!(data & BTRFS_BLOCK_GROUP_DATA))
5242 trans->block_group = block_group->key.objectid;
5244 btrfs_put_block_group(block_group);
5251 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5252 int dump_block_groups)
5254 struct btrfs_block_group_cache *cache;
5257 spin_lock(&info->lock);
5258 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
5259 (unsigned long long)(info->total_bytes - info->bytes_used -
5260 info->bytes_pinned - info->bytes_reserved -
5261 info->bytes_readonly),
5262 (info->full) ? "" : "not ");
5263 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5264 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5265 (unsigned long long)info->total_bytes,
5266 (unsigned long long)info->bytes_used,
5267 (unsigned long long)info->bytes_pinned,
5268 (unsigned long long)info->bytes_reserved,
5269 (unsigned long long)info->bytes_may_use,
5270 (unsigned long long)info->bytes_readonly);
5271 spin_unlock(&info->lock);
5273 if (!dump_block_groups)
5276 down_read(&info->groups_sem);
5278 list_for_each_entry(cache, &info->block_groups[index], list) {
5279 spin_lock(&cache->lock);
5280 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5281 "%llu pinned %llu reserved\n",
5282 (unsigned long long)cache->key.objectid,
5283 (unsigned long long)cache->key.offset,
5284 (unsigned long long)btrfs_block_group_used(&cache->item),
5285 (unsigned long long)cache->pinned,
5286 (unsigned long long)cache->reserved);
5287 btrfs_dump_free_space(cache, bytes);
5288 spin_unlock(&cache->lock);
5290 if (++index < BTRFS_NR_RAID_TYPES)
5292 up_read(&info->groups_sem);
5295 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5296 struct btrfs_root *root,
5297 u64 num_bytes, u64 min_alloc_size,
5298 u64 empty_size, u64 hint_byte,
5299 u64 search_end, struct btrfs_key *ins,
5303 u64 search_start = 0;
5305 data = btrfs_get_alloc_profile(root, data);
5308 * the only place that sets empty_size is btrfs_realloc_node, which
5309 * is not called recursively on allocations
5311 if (empty_size || root->ref_cows)
5312 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5313 num_bytes + 2 * 1024 * 1024, data, 0);
5315 WARN_ON(num_bytes < root->sectorsize);
5316 ret = find_free_extent(trans, root, num_bytes, empty_size,
5317 search_start, search_end, hint_byte,
5320 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5321 num_bytes = num_bytes >> 1;
5322 num_bytes = num_bytes & ~(root->sectorsize - 1);
5323 num_bytes = max(num_bytes, min_alloc_size);
5324 do_chunk_alloc(trans, root->fs_info->extent_root,
5325 num_bytes, data, 1);
5328 if (ret == -ENOSPC) {
5329 struct btrfs_space_info *sinfo;
5331 sinfo = __find_space_info(root->fs_info, data);
5332 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5333 "wanted %llu\n", (unsigned long long)data,
5334 (unsigned long long)num_bytes);
5335 dump_space_info(sinfo, num_bytes, 1);
5341 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
5343 struct btrfs_block_group_cache *cache;
5346 cache = btrfs_lookup_block_group(root->fs_info, start);
5348 printk(KERN_ERR "Unable to find block group for %llu\n",
5349 (unsigned long long)start);
5353 ret = btrfs_discard_extent(root, start, len);
5355 btrfs_add_free_space(cache, start, len);
5356 update_reserved_bytes(cache, len, 0, 1);
5357 btrfs_put_block_group(cache);
5362 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5363 struct btrfs_root *root,
5364 u64 parent, u64 root_objectid,
5365 u64 flags, u64 owner, u64 offset,
5366 struct btrfs_key *ins, int ref_mod)
5369 struct btrfs_fs_info *fs_info = root->fs_info;
5370 struct btrfs_extent_item *extent_item;
5371 struct btrfs_extent_inline_ref *iref;
5372 struct btrfs_path *path;
5373 struct extent_buffer *leaf;
5378 type = BTRFS_SHARED_DATA_REF_KEY;
5380 type = BTRFS_EXTENT_DATA_REF_KEY;
5382 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5384 path = btrfs_alloc_path();
5387 path->leave_spinning = 1;
5388 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5392 leaf = path->nodes[0];
5393 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5394 struct btrfs_extent_item);
5395 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5396 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5397 btrfs_set_extent_flags(leaf, extent_item,
5398 flags | BTRFS_EXTENT_FLAG_DATA);
5400 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5401 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5403 struct btrfs_shared_data_ref *ref;
5404 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5405 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5406 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5408 struct btrfs_extent_data_ref *ref;
5409 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5410 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5411 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5412 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5413 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5416 btrfs_mark_buffer_dirty(path->nodes[0]);
5417 btrfs_free_path(path);
5419 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5421 printk(KERN_ERR "btrfs update block group failed for %llu "
5422 "%llu\n", (unsigned long long)ins->objectid,
5423 (unsigned long long)ins->offset);
5429 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5430 struct btrfs_root *root,
5431 u64 parent, u64 root_objectid,
5432 u64 flags, struct btrfs_disk_key *key,
5433 int level, struct btrfs_key *ins)
5436 struct btrfs_fs_info *fs_info = root->fs_info;
5437 struct btrfs_extent_item *extent_item;
5438 struct btrfs_tree_block_info *block_info;
5439 struct btrfs_extent_inline_ref *iref;
5440 struct btrfs_path *path;
5441 struct extent_buffer *leaf;
5442 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5444 path = btrfs_alloc_path();
5447 path->leave_spinning = 1;
5448 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5452 leaf = path->nodes[0];
5453 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5454 struct btrfs_extent_item);
5455 btrfs_set_extent_refs(leaf, extent_item, 1);
5456 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5457 btrfs_set_extent_flags(leaf, extent_item,
5458 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5459 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5461 btrfs_set_tree_block_key(leaf, block_info, key);
5462 btrfs_set_tree_block_level(leaf, block_info, level);
5464 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5466 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5467 btrfs_set_extent_inline_ref_type(leaf, iref,
5468 BTRFS_SHARED_BLOCK_REF_KEY);
5469 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5471 btrfs_set_extent_inline_ref_type(leaf, iref,
5472 BTRFS_TREE_BLOCK_REF_KEY);
5473 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5476 btrfs_mark_buffer_dirty(leaf);
5477 btrfs_free_path(path);
5479 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5481 printk(KERN_ERR "btrfs update block group failed for %llu "
5482 "%llu\n", (unsigned long long)ins->objectid,
5483 (unsigned long long)ins->offset);
5489 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5490 struct btrfs_root *root,
5491 u64 root_objectid, u64 owner,
5492 u64 offset, struct btrfs_key *ins)
5496 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5498 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5499 0, root_objectid, owner, offset,
5500 BTRFS_ADD_DELAYED_EXTENT, NULL);
5505 * this is used by the tree logging recovery code. It records that
5506 * an extent has been allocated and makes sure to clear the free
5507 * space cache bits as well
5509 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5510 struct btrfs_root *root,
5511 u64 root_objectid, u64 owner, u64 offset,
5512 struct btrfs_key *ins)
5515 struct btrfs_block_group_cache *block_group;
5516 struct btrfs_caching_control *caching_ctl;
5517 u64 start = ins->objectid;
5518 u64 num_bytes = ins->offset;
5520 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5521 cache_block_group(block_group, trans, 0);
5522 caching_ctl = get_caching_control(block_group);
5525 BUG_ON(!block_group_cache_done(block_group));
5526 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5529 mutex_lock(&caching_ctl->mutex);
5531 if (start >= caching_ctl->progress) {
5532 ret = add_excluded_extent(root, start, num_bytes);
5534 } else if (start + num_bytes <= caching_ctl->progress) {
5535 ret = btrfs_remove_free_space(block_group,
5539 num_bytes = caching_ctl->progress - start;
5540 ret = btrfs_remove_free_space(block_group,
5544 start = caching_ctl->progress;
5545 num_bytes = ins->objectid + ins->offset -
5546 caching_ctl->progress;
5547 ret = add_excluded_extent(root, start, num_bytes);
5551 mutex_unlock(&caching_ctl->mutex);
5552 put_caching_control(caching_ctl);
5555 ret = update_reserved_bytes(block_group, ins->offset, 1, 1);
5557 btrfs_put_block_group(block_group);
5558 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5559 0, owner, offset, ins, 1);
5563 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5564 struct btrfs_root *root,
5565 u64 bytenr, u32 blocksize,
5568 struct extent_buffer *buf;
5570 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5572 return ERR_PTR(-ENOMEM);
5573 btrfs_set_header_generation(buf, trans->transid);
5574 btrfs_set_buffer_lockdep_class(buf, level);
5575 btrfs_tree_lock(buf);
5576 clean_tree_block(trans, root, buf);
5578 btrfs_set_lock_blocking(buf);
5579 btrfs_set_buffer_uptodate(buf);
5581 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5583 * we allow two log transactions at a time, use different
5584 * EXENT bit to differentiate dirty pages.
5586 if (root->log_transid % 2 == 0)
5587 set_extent_dirty(&root->dirty_log_pages, buf->start,
5588 buf->start + buf->len - 1, GFP_NOFS);
5590 set_extent_new(&root->dirty_log_pages, buf->start,
5591 buf->start + buf->len - 1, GFP_NOFS);
5593 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5594 buf->start + buf->len - 1, GFP_NOFS);
5596 trans->blocks_used++;
5597 /* this returns a buffer locked for blocking */
5601 static struct btrfs_block_rsv *
5602 use_block_rsv(struct btrfs_trans_handle *trans,
5603 struct btrfs_root *root, u32 blocksize)
5605 struct btrfs_block_rsv *block_rsv;
5608 block_rsv = get_block_rsv(trans, root);
5610 if (block_rsv->size == 0) {
5611 ret = reserve_metadata_bytes(trans, root, block_rsv,
5614 return ERR_PTR(ret);
5618 ret = block_rsv_use_bytes(block_rsv, blocksize);
5622 return ERR_PTR(-ENOSPC);
5625 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5627 block_rsv_add_bytes(block_rsv, blocksize, 0);
5628 block_rsv_release_bytes(block_rsv, NULL, 0);
5632 * finds a free extent and does all the dirty work required for allocation
5633 * returns the key for the extent through ins, and a tree buffer for
5634 * the first block of the extent through buf.
5636 * returns the tree buffer or NULL.
5638 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5639 struct btrfs_root *root, u32 blocksize,
5640 u64 parent, u64 root_objectid,
5641 struct btrfs_disk_key *key, int level,
5642 u64 hint, u64 empty_size)
5644 struct btrfs_key ins;
5645 struct btrfs_block_rsv *block_rsv;
5646 struct extent_buffer *buf;
5651 block_rsv = use_block_rsv(trans, root, blocksize);
5652 if (IS_ERR(block_rsv))
5653 return ERR_CAST(block_rsv);
5655 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5656 empty_size, hint, (u64)-1, &ins, 0);
5658 unuse_block_rsv(block_rsv, blocksize);
5659 return ERR_PTR(ret);
5662 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5664 BUG_ON(IS_ERR(buf));
5666 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5668 parent = ins.objectid;
5669 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5673 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5674 struct btrfs_delayed_extent_op *extent_op;
5675 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5678 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5680 memset(&extent_op->key, 0, sizeof(extent_op->key));
5681 extent_op->flags_to_set = flags;
5682 extent_op->update_key = 1;
5683 extent_op->update_flags = 1;
5684 extent_op->is_data = 0;
5686 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5687 ins.offset, parent, root_objectid,
5688 level, BTRFS_ADD_DELAYED_EXTENT,
5695 struct walk_control {
5696 u64 refs[BTRFS_MAX_LEVEL];
5697 u64 flags[BTRFS_MAX_LEVEL];
5698 struct btrfs_key update_progress;
5708 #define DROP_REFERENCE 1
5709 #define UPDATE_BACKREF 2
5711 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5712 struct btrfs_root *root,
5713 struct walk_control *wc,
5714 struct btrfs_path *path)
5722 struct btrfs_key key;
5723 struct extent_buffer *eb;
5728 if (path->slots[wc->level] < wc->reada_slot) {
5729 wc->reada_count = wc->reada_count * 2 / 3;
5730 wc->reada_count = max(wc->reada_count, 2);
5732 wc->reada_count = wc->reada_count * 3 / 2;
5733 wc->reada_count = min_t(int, wc->reada_count,
5734 BTRFS_NODEPTRS_PER_BLOCK(root));
5737 eb = path->nodes[wc->level];
5738 nritems = btrfs_header_nritems(eb);
5739 blocksize = btrfs_level_size(root, wc->level - 1);
5741 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5742 if (nread >= wc->reada_count)
5746 bytenr = btrfs_node_blockptr(eb, slot);
5747 generation = btrfs_node_ptr_generation(eb, slot);
5749 if (slot == path->slots[wc->level])
5752 if (wc->stage == UPDATE_BACKREF &&
5753 generation <= root->root_key.offset)
5756 /* We don't lock the tree block, it's OK to be racy here */
5757 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5762 if (wc->stage == DROP_REFERENCE) {
5766 if (wc->level == 1 &&
5767 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5769 if (!wc->update_ref ||
5770 generation <= root->root_key.offset)
5772 btrfs_node_key_to_cpu(eb, &key, slot);
5773 ret = btrfs_comp_cpu_keys(&key,
5774 &wc->update_progress);
5778 if (wc->level == 1 &&
5779 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5783 ret = readahead_tree_block(root, bytenr, blocksize,
5789 wc->reada_slot = slot;
5793 * hepler to process tree block while walking down the tree.
5795 * when wc->stage == UPDATE_BACKREF, this function updates
5796 * back refs for pointers in the block.
5798 * NOTE: return value 1 means we should stop walking down.
5800 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5801 struct btrfs_root *root,
5802 struct btrfs_path *path,
5803 struct walk_control *wc, int lookup_info)
5805 int level = wc->level;
5806 struct extent_buffer *eb = path->nodes[level];
5807 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5810 if (wc->stage == UPDATE_BACKREF &&
5811 btrfs_header_owner(eb) != root->root_key.objectid)
5815 * when reference count of tree block is 1, it won't increase
5816 * again. once full backref flag is set, we never clear it.
5819 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5820 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5821 BUG_ON(!path->locks[level]);
5822 ret = btrfs_lookup_extent_info(trans, root,
5827 BUG_ON(wc->refs[level] == 0);
5830 if (wc->stage == DROP_REFERENCE) {
5831 if (wc->refs[level] > 1)
5834 if (path->locks[level] && !wc->keep_locks) {
5835 btrfs_tree_unlock(eb);
5836 path->locks[level] = 0;
5841 /* wc->stage == UPDATE_BACKREF */
5842 if (!(wc->flags[level] & flag)) {
5843 BUG_ON(!path->locks[level]);
5844 ret = btrfs_inc_ref(trans, root, eb, 1);
5846 ret = btrfs_dec_ref(trans, root, eb, 0);
5848 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5851 wc->flags[level] |= flag;
5855 * the block is shared by multiple trees, so it's not good to
5856 * keep the tree lock
5858 if (path->locks[level] && level > 0) {
5859 btrfs_tree_unlock(eb);
5860 path->locks[level] = 0;
5866 * hepler to process tree block pointer.
5868 * when wc->stage == DROP_REFERENCE, this function checks
5869 * reference count of the block pointed to. if the block
5870 * is shared and we need update back refs for the subtree
5871 * rooted at the block, this function changes wc->stage to
5872 * UPDATE_BACKREF. if the block is shared and there is no
5873 * need to update back, this function drops the reference
5876 * NOTE: return value 1 means we should stop walking down.
5878 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5879 struct btrfs_root *root,
5880 struct btrfs_path *path,
5881 struct walk_control *wc, int *lookup_info)
5887 struct btrfs_key key;
5888 struct extent_buffer *next;
5889 int level = wc->level;
5893 generation = btrfs_node_ptr_generation(path->nodes[level],
5894 path->slots[level]);
5896 * if the lower level block was created before the snapshot
5897 * was created, we know there is no need to update back refs
5900 if (wc->stage == UPDATE_BACKREF &&
5901 generation <= root->root_key.offset) {
5906 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
5907 blocksize = btrfs_level_size(root, level - 1);
5909 next = btrfs_find_tree_block(root, bytenr, blocksize);
5911 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
5916 btrfs_tree_lock(next);
5917 btrfs_set_lock_blocking(next);
5919 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5920 &wc->refs[level - 1],
5921 &wc->flags[level - 1]);
5923 BUG_ON(wc->refs[level - 1] == 0);
5926 if (wc->stage == DROP_REFERENCE) {
5927 if (wc->refs[level - 1] > 1) {
5929 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5932 if (!wc->update_ref ||
5933 generation <= root->root_key.offset)
5936 btrfs_node_key_to_cpu(path->nodes[level], &key,
5937 path->slots[level]);
5938 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
5942 wc->stage = UPDATE_BACKREF;
5943 wc->shared_level = level - 1;
5947 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5951 if (!btrfs_buffer_uptodate(next, generation)) {
5952 btrfs_tree_unlock(next);
5953 free_extent_buffer(next);
5959 if (reada && level == 1)
5960 reada_walk_down(trans, root, wc, path);
5961 next = read_tree_block(root, bytenr, blocksize, generation);
5962 btrfs_tree_lock(next);
5963 btrfs_set_lock_blocking(next);
5967 BUG_ON(level != btrfs_header_level(next));
5968 path->nodes[level] = next;
5969 path->slots[level] = 0;
5970 path->locks[level] = 1;
5976 wc->refs[level - 1] = 0;
5977 wc->flags[level - 1] = 0;
5978 if (wc->stage == DROP_REFERENCE) {
5979 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
5980 parent = path->nodes[level]->start;
5982 BUG_ON(root->root_key.objectid !=
5983 btrfs_header_owner(path->nodes[level]));
5987 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
5988 root->root_key.objectid, level - 1, 0);
5991 btrfs_tree_unlock(next);
5992 free_extent_buffer(next);
5998 * hepler to process tree block while walking up the tree.
6000 * when wc->stage == DROP_REFERENCE, this function drops
6001 * reference count on the block.
6003 * when wc->stage == UPDATE_BACKREF, this function changes
6004 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6005 * to UPDATE_BACKREF previously while processing the block.
6007 * NOTE: return value 1 means we should stop walking up.
6009 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6010 struct btrfs_root *root,
6011 struct btrfs_path *path,
6012 struct walk_control *wc)
6015 int level = wc->level;
6016 struct extent_buffer *eb = path->nodes[level];
6019 if (wc->stage == UPDATE_BACKREF) {
6020 BUG_ON(wc->shared_level < level);
6021 if (level < wc->shared_level)
6024 ret = find_next_key(path, level + 1, &wc->update_progress);
6028 wc->stage = DROP_REFERENCE;
6029 wc->shared_level = -1;
6030 path->slots[level] = 0;
6033 * check reference count again if the block isn't locked.
6034 * we should start walking down the tree again if reference
6037 if (!path->locks[level]) {
6039 btrfs_tree_lock(eb);
6040 btrfs_set_lock_blocking(eb);
6041 path->locks[level] = 1;
6043 ret = btrfs_lookup_extent_info(trans, root,
6048 BUG_ON(wc->refs[level] == 0);
6049 if (wc->refs[level] == 1) {
6050 btrfs_tree_unlock(eb);
6051 path->locks[level] = 0;
6057 /* wc->stage == DROP_REFERENCE */
6058 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6060 if (wc->refs[level] == 1) {
6062 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6063 ret = btrfs_dec_ref(trans, root, eb, 1);
6065 ret = btrfs_dec_ref(trans, root, eb, 0);
6068 /* make block locked assertion in clean_tree_block happy */
6069 if (!path->locks[level] &&
6070 btrfs_header_generation(eb) == trans->transid) {
6071 btrfs_tree_lock(eb);
6072 btrfs_set_lock_blocking(eb);
6073 path->locks[level] = 1;
6075 clean_tree_block(trans, root, eb);
6078 if (eb == root->node) {
6079 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6082 BUG_ON(root->root_key.objectid !=
6083 btrfs_header_owner(eb));
6085 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6086 parent = path->nodes[level + 1]->start;
6088 BUG_ON(root->root_key.objectid !=
6089 btrfs_header_owner(path->nodes[level + 1]));
6092 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6094 wc->refs[level] = 0;
6095 wc->flags[level] = 0;
6099 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6100 struct btrfs_root *root,
6101 struct btrfs_path *path,
6102 struct walk_control *wc)
6104 int level = wc->level;
6105 int lookup_info = 1;
6108 while (level >= 0) {
6109 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6116 if (path->slots[level] >=
6117 btrfs_header_nritems(path->nodes[level]))
6120 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6122 path->slots[level]++;
6131 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6132 struct btrfs_root *root,
6133 struct btrfs_path *path,
6134 struct walk_control *wc, int max_level)
6136 int level = wc->level;
6139 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6140 while (level < max_level && path->nodes[level]) {
6142 if (path->slots[level] + 1 <
6143 btrfs_header_nritems(path->nodes[level])) {
6144 path->slots[level]++;
6147 ret = walk_up_proc(trans, root, path, wc);
6151 if (path->locks[level]) {
6152 btrfs_tree_unlock(path->nodes[level]);
6153 path->locks[level] = 0;
6155 free_extent_buffer(path->nodes[level]);
6156 path->nodes[level] = NULL;
6164 * drop a subvolume tree.
6166 * this function traverses the tree freeing any blocks that only
6167 * referenced by the tree.
6169 * when a shared tree block is found. this function decreases its
6170 * reference count by one. if update_ref is true, this function
6171 * also make sure backrefs for the shared block and all lower level
6172 * blocks are properly updated.
6174 int btrfs_drop_snapshot(struct btrfs_root *root,
6175 struct btrfs_block_rsv *block_rsv, int update_ref)
6177 struct btrfs_path *path;
6178 struct btrfs_trans_handle *trans;
6179 struct btrfs_root *tree_root = root->fs_info->tree_root;
6180 struct btrfs_root_item *root_item = &root->root_item;
6181 struct walk_control *wc;
6182 struct btrfs_key key;
6187 path = btrfs_alloc_path();
6190 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6193 trans = btrfs_start_transaction(tree_root, 0);
6195 trans->block_rsv = block_rsv;
6197 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6198 level = btrfs_header_level(root->node);
6199 path->nodes[level] = btrfs_lock_root_node(root);
6200 btrfs_set_lock_blocking(path->nodes[level]);
6201 path->slots[level] = 0;
6202 path->locks[level] = 1;
6203 memset(&wc->update_progress, 0,
6204 sizeof(wc->update_progress));
6206 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6207 memcpy(&wc->update_progress, &key,
6208 sizeof(wc->update_progress));
6210 level = root_item->drop_level;
6212 path->lowest_level = level;
6213 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6214 path->lowest_level = 0;
6222 * unlock our path, this is safe because only this
6223 * function is allowed to delete this snapshot
6225 btrfs_unlock_up_safe(path, 0);
6227 level = btrfs_header_level(root->node);
6229 btrfs_tree_lock(path->nodes[level]);
6230 btrfs_set_lock_blocking(path->nodes[level]);
6232 ret = btrfs_lookup_extent_info(trans, root,
6233 path->nodes[level]->start,
6234 path->nodes[level]->len,
6238 BUG_ON(wc->refs[level] == 0);
6240 if (level == root_item->drop_level)
6243 btrfs_tree_unlock(path->nodes[level]);
6244 WARN_ON(wc->refs[level] != 1);
6250 wc->shared_level = -1;
6251 wc->stage = DROP_REFERENCE;
6252 wc->update_ref = update_ref;
6254 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6257 ret = walk_down_tree(trans, root, path, wc);
6263 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6270 BUG_ON(wc->stage != DROP_REFERENCE);
6274 if (wc->stage == DROP_REFERENCE) {
6276 btrfs_node_key(path->nodes[level],
6277 &root_item->drop_progress,
6278 path->slots[level]);
6279 root_item->drop_level = level;
6282 BUG_ON(wc->level == 0);
6283 if (btrfs_should_end_transaction(trans, tree_root)) {
6284 ret = btrfs_update_root(trans, tree_root,
6289 btrfs_end_transaction_throttle(trans, tree_root);
6290 trans = btrfs_start_transaction(tree_root, 0);
6292 trans->block_rsv = block_rsv;
6295 btrfs_release_path(root, path);
6298 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6301 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6302 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6306 ret = btrfs_del_orphan_item(trans, tree_root,
6307 root->root_key.objectid);
6312 if (root->in_radix) {
6313 btrfs_free_fs_root(tree_root->fs_info, root);
6315 free_extent_buffer(root->node);
6316 free_extent_buffer(root->commit_root);
6320 btrfs_end_transaction_throttle(trans, tree_root);
6322 btrfs_free_path(path);
6327 * drop subtree rooted at tree block 'node'.
6329 * NOTE: this function will unlock and release tree block 'node'
6331 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6332 struct btrfs_root *root,
6333 struct extent_buffer *node,
6334 struct extent_buffer *parent)
6336 struct btrfs_path *path;
6337 struct walk_control *wc;
6343 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6345 path = btrfs_alloc_path();
6348 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6351 btrfs_assert_tree_locked(parent);
6352 parent_level = btrfs_header_level(parent);
6353 extent_buffer_get(parent);
6354 path->nodes[parent_level] = parent;
6355 path->slots[parent_level] = btrfs_header_nritems(parent);
6357 btrfs_assert_tree_locked(node);
6358 level = btrfs_header_level(node);
6359 path->nodes[level] = node;
6360 path->slots[level] = 0;
6361 path->locks[level] = 1;
6363 wc->refs[parent_level] = 1;
6364 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6366 wc->shared_level = -1;
6367 wc->stage = DROP_REFERENCE;
6370 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6373 wret = walk_down_tree(trans, root, path, wc);
6379 wret = walk_up_tree(trans, root, path, wc, parent_level);
6387 btrfs_free_path(path);
6392 static unsigned long calc_ra(unsigned long start, unsigned long last,
6395 return min(last, start + nr - 1);
6398 static noinline int relocate_inode_pages(struct inode *inode, u64 start,
6403 unsigned long first_index;
6404 unsigned long last_index;
6407 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6408 struct file_ra_state *ra;
6409 struct btrfs_ordered_extent *ordered;
6410 unsigned int total_read = 0;
6411 unsigned int total_dirty = 0;
6414 ra = kzalloc(sizeof(*ra), GFP_NOFS);
6416 mutex_lock(&inode->i_mutex);
6417 first_index = start >> PAGE_CACHE_SHIFT;
6418 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
6420 /* make sure the dirty trick played by the caller work */
6421 ret = invalidate_inode_pages2_range(inode->i_mapping,
6422 first_index, last_index);
6426 file_ra_state_init(ra, inode->i_mapping);
6428 for (i = first_index ; i <= last_index; i++) {
6429 if (total_read % ra->ra_pages == 0) {
6430 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
6431 calc_ra(i, last_index, ra->ra_pages));
6435 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
6437 page = grab_cache_page(inode->i_mapping, i);
6442 if (!PageUptodate(page)) {
6443 btrfs_readpage(NULL, page);
6445 if (!PageUptodate(page)) {
6447 page_cache_release(page);
6452 wait_on_page_writeback(page);
6454 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
6455 page_end = page_start + PAGE_CACHE_SIZE - 1;
6456 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
6458 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6460 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6462 page_cache_release(page);
6463 btrfs_start_ordered_extent(inode, ordered, 1);
6464 btrfs_put_ordered_extent(ordered);
6467 set_page_extent_mapped(page);
6469 if (i == first_index)
6470 set_extent_bits(io_tree, page_start, page_end,
6471 EXTENT_BOUNDARY, GFP_NOFS);
6472 btrfs_set_extent_delalloc(inode, page_start, page_end);
6474 set_page_dirty(page);
6477 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6479 page_cache_release(page);
6484 mutex_unlock(&inode->i_mutex);
6485 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
6489 static noinline int relocate_data_extent(struct inode *reloc_inode,
6490 struct btrfs_key *extent_key,
6493 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6494 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
6495 struct extent_map *em;
6496 u64 start = extent_key->objectid - offset;
6497 u64 end = start + extent_key->offset - 1;
6499 em = alloc_extent_map(GFP_NOFS);
6500 BUG_ON(!em || IS_ERR(em));
6503 em->len = extent_key->offset;
6504 em->block_len = extent_key->offset;
6505 em->block_start = extent_key->objectid;
6506 em->bdev = root->fs_info->fs_devices->latest_bdev;
6507 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6509 /* setup extent map to cheat btrfs_readpage */
6510 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6513 write_lock(&em_tree->lock);
6514 ret = add_extent_mapping(em_tree, em);
6515 write_unlock(&em_tree->lock);
6516 if (ret != -EEXIST) {
6517 free_extent_map(em);
6520 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
6522 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6524 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
6527 struct btrfs_ref_path {
6529 u64 nodes[BTRFS_MAX_LEVEL];
6531 u64 root_generation;
6538 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
6539 u64 new_nodes[BTRFS_MAX_LEVEL];
6542 struct disk_extent {
6553 static int is_cowonly_root(u64 root_objectid)
6555 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
6556 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
6557 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
6558 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
6559 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
6560 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
6565 static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
6566 struct btrfs_root *extent_root,
6567 struct btrfs_ref_path *ref_path,
6570 struct extent_buffer *leaf;
6571 struct btrfs_path *path;
6572 struct btrfs_extent_ref *ref;
6573 struct btrfs_key key;
6574 struct btrfs_key found_key;
6580 path = btrfs_alloc_path();
6585 ref_path->lowest_level = -1;
6586 ref_path->current_level = -1;
6587 ref_path->shared_level = -1;
6591 level = ref_path->current_level - 1;
6592 while (level >= -1) {
6594 if (level < ref_path->lowest_level)
6598 bytenr = ref_path->nodes[level];
6600 bytenr = ref_path->extent_start;
6601 BUG_ON(bytenr == 0);
6603 parent = ref_path->nodes[level + 1];
6604 ref_path->nodes[level + 1] = 0;
6605 ref_path->current_level = level;
6606 BUG_ON(parent == 0);
6608 key.objectid = bytenr;
6609 key.offset = parent + 1;
6610 key.type = BTRFS_EXTENT_REF_KEY;
6612 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6617 leaf = path->nodes[0];
6618 nritems = btrfs_header_nritems(leaf);
6619 if (path->slots[0] >= nritems) {
6620 ret = btrfs_next_leaf(extent_root, path);
6625 leaf = path->nodes[0];
6628 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6629 if (found_key.objectid == bytenr &&
6630 found_key.type == BTRFS_EXTENT_REF_KEY) {
6631 if (level < ref_path->shared_level)
6632 ref_path->shared_level = level;
6637 btrfs_release_path(extent_root, path);
6640 /* reached lowest level */
6644 level = ref_path->current_level;
6645 while (level < BTRFS_MAX_LEVEL - 1) {
6649 bytenr = ref_path->nodes[level];
6651 bytenr = ref_path->extent_start;
6653 BUG_ON(bytenr == 0);
6655 key.objectid = bytenr;
6657 key.type = BTRFS_EXTENT_REF_KEY;
6659 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6663 leaf = path->nodes[0];
6664 nritems = btrfs_header_nritems(leaf);
6665 if (path->slots[0] >= nritems) {
6666 ret = btrfs_next_leaf(extent_root, path);
6670 /* the extent was freed by someone */
6671 if (ref_path->lowest_level == level)
6673 btrfs_release_path(extent_root, path);
6676 leaf = path->nodes[0];
6679 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6680 if (found_key.objectid != bytenr ||
6681 found_key.type != BTRFS_EXTENT_REF_KEY) {
6682 /* the extent was freed by someone */
6683 if (ref_path->lowest_level == level) {
6687 btrfs_release_path(extent_root, path);
6691 ref = btrfs_item_ptr(leaf, path->slots[0],
6692 struct btrfs_extent_ref);
6693 ref_objectid = btrfs_ref_objectid(leaf, ref);
6694 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
6696 level = (int)ref_objectid;
6697 BUG_ON(level >= BTRFS_MAX_LEVEL);
6698 ref_path->lowest_level = level;
6699 ref_path->current_level = level;
6700 ref_path->nodes[level] = bytenr;
6702 WARN_ON(ref_objectid != level);
6705 WARN_ON(level != -1);
6709 if (ref_path->lowest_level == level) {
6710 ref_path->owner_objectid = ref_objectid;
6711 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
6715 * the block is tree root or the block isn't in reference
6718 if (found_key.objectid == found_key.offset ||
6719 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
6720 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6721 ref_path->root_generation =
6722 btrfs_ref_generation(leaf, ref);
6724 /* special reference from the tree log */
6725 ref_path->nodes[0] = found_key.offset;
6726 ref_path->current_level = 0;
6733 BUG_ON(ref_path->nodes[level] != 0);
6734 ref_path->nodes[level] = found_key.offset;
6735 ref_path->current_level = level;
6738 * the reference was created in the running transaction,
6739 * no need to continue walking up.
6741 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
6742 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6743 ref_path->root_generation =
6744 btrfs_ref_generation(leaf, ref);
6749 btrfs_release_path(extent_root, path);
6752 /* reached max tree level, but no tree root found. */
6755 btrfs_free_path(path);
6759 static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
6760 struct btrfs_root *extent_root,
6761 struct btrfs_ref_path *ref_path,
6764 memset(ref_path, 0, sizeof(*ref_path));
6765 ref_path->extent_start = extent_start;
6767 return __next_ref_path(trans, extent_root, ref_path, 1);
6770 static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
6771 struct btrfs_root *extent_root,
6772 struct btrfs_ref_path *ref_path)
6774 return __next_ref_path(trans, extent_root, ref_path, 0);
6777 static noinline int get_new_locations(struct inode *reloc_inode,
6778 struct btrfs_key *extent_key,
6779 u64 offset, int no_fragment,
6780 struct disk_extent **extents,
6783 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6784 struct btrfs_path *path;
6785 struct btrfs_file_extent_item *fi;
6786 struct extent_buffer *leaf;
6787 struct disk_extent *exts = *extents;
6788 struct btrfs_key found_key;
6793 int max = *nr_extents;
6796 WARN_ON(!no_fragment && *extents);
6799 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
6804 path = btrfs_alloc_path();
6807 cur_pos = extent_key->objectid - offset;
6808 last_byte = extent_key->objectid + extent_key->offset;
6809 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
6819 leaf = path->nodes[0];
6820 nritems = btrfs_header_nritems(leaf);
6821 if (path->slots[0] >= nritems) {
6822 ret = btrfs_next_leaf(root, path);
6827 leaf = path->nodes[0];
6830 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6831 if (found_key.offset != cur_pos ||
6832 found_key.type != BTRFS_EXTENT_DATA_KEY ||
6833 found_key.objectid != reloc_inode->i_ino)
6836 fi = btrfs_item_ptr(leaf, path->slots[0],
6837 struct btrfs_file_extent_item);
6838 if (btrfs_file_extent_type(leaf, fi) !=
6839 BTRFS_FILE_EXTENT_REG ||
6840 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6844 struct disk_extent *old = exts;
6846 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
6847 memcpy(exts, old, sizeof(*exts) * nr);
6848 if (old != *extents)
6852 exts[nr].disk_bytenr =
6853 btrfs_file_extent_disk_bytenr(leaf, fi);
6854 exts[nr].disk_num_bytes =
6855 btrfs_file_extent_disk_num_bytes(leaf, fi);
6856 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
6857 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6858 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6859 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
6860 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
6861 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
6863 BUG_ON(exts[nr].offset > 0);
6864 BUG_ON(exts[nr].compression || exts[nr].encryption);
6865 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
6867 cur_pos += exts[nr].num_bytes;
6870 if (cur_pos + offset >= last_byte)
6880 BUG_ON(cur_pos + offset > last_byte);
6881 if (cur_pos + offset < last_byte) {
6887 btrfs_free_path(path);
6889 if (exts != *extents)
6898 static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
6899 struct btrfs_root *root,
6900 struct btrfs_path *path,
6901 struct btrfs_key *extent_key,
6902 struct btrfs_key *leaf_key,
6903 struct btrfs_ref_path *ref_path,
6904 struct disk_extent *new_extents,
6907 struct extent_buffer *leaf;
6908 struct btrfs_file_extent_item *fi;
6909 struct inode *inode = NULL;
6910 struct btrfs_key key;
6915 u64 search_end = (u64)-1;
6918 int extent_locked = 0;
6922 memcpy(&key, leaf_key, sizeof(key));
6923 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6924 if (key.objectid < ref_path->owner_objectid ||
6925 (key.objectid == ref_path->owner_objectid &&
6926 key.type < BTRFS_EXTENT_DATA_KEY)) {
6927 key.objectid = ref_path->owner_objectid;
6928 key.type = BTRFS_EXTENT_DATA_KEY;
6934 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
6938 leaf = path->nodes[0];
6939 nritems = btrfs_header_nritems(leaf);
6941 if (extent_locked && ret > 0) {
6943 * the file extent item was modified by someone
6944 * before the extent got locked.
6946 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6947 lock_end, GFP_NOFS);
6951 if (path->slots[0] >= nritems) {
6952 if (++nr_scaned > 2)
6955 BUG_ON(extent_locked);
6956 ret = btrfs_next_leaf(root, path);
6961 leaf = path->nodes[0];
6962 nritems = btrfs_header_nritems(leaf);
6965 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
6967 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6968 if ((key.objectid > ref_path->owner_objectid) ||
6969 (key.objectid == ref_path->owner_objectid &&
6970 key.type > BTRFS_EXTENT_DATA_KEY) ||
6971 key.offset >= search_end)
6975 if (inode && key.objectid != inode->i_ino) {
6976 BUG_ON(extent_locked);
6977 btrfs_release_path(root, path);
6978 mutex_unlock(&inode->i_mutex);
6984 if (key.type != BTRFS_EXTENT_DATA_KEY) {
6989 fi = btrfs_item_ptr(leaf, path->slots[0],
6990 struct btrfs_file_extent_item);
6991 extent_type = btrfs_file_extent_type(leaf, fi);
6992 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
6993 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
6994 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
6995 extent_key->objectid)) {
7001 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7002 ext_offset = btrfs_file_extent_offset(leaf, fi);
7004 if (search_end == (u64)-1) {
7005 search_end = key.offset - ext_offset +
7006 btrfs_file_extent_ram_bytes(leaf, fi);
7009 if (!extent_locked) {
7010 lock_start = key.offset;
7011 lock_end = lock_start + num_bytes - 1;
7013 if (lock_start > key.offset ||
7014 lock_end + 1 < key.offset + num_bytes) {
7015 unlock_extent(&BTRFS_I(inode)->io_tree,
7016 lock_start, lock_end, GFP_NOFS);
7022 btrfs_release_path(root, path);
7024 inode = btrfs_iget_locked(root->fs_info->sb,
7025 key.objectid, root);
7026 if (inode->i_state & I_NEW) {
7027 BTRFS_I(inode)->root = root;
7028 BTRFS_I(inode)->location.objectid =
7030 BTRFS_I(inode)->location.type =
7031 BTRFS_INODE_ITEM_KEY;
7032 BTRFS_I(inode)->location.offset = 0;
7033 btrfs_read_locked_inode(inode);
7034 unlock_new_inode(inode);
7037 * some code call btrfs_commit_transaction while
7038 * holding the i_mutex, so we can't use mutex_lock
7041 if (is_bad_inode(inode) ||
7042 !mutex_trylock(&inode->i_mutex)) {
7045 key.offset = (u64)-1;
7050 if (!extent_locked) {
7051 struct btrfs_ordered_extent *ordered;
7053 btrfs_release_path(root, path);
7055 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7056 lock_end, GFP_NOFS);
7057 ordered = btrfs_lookup_first_ordered_extent(inode,
7060 ordered->file_offset <= lock_end &&
7061 ordered->file_offset + ordered->len > lock_start) {
7062 unlock_extent(&BTRFS_I(inode)->io_tree,
7063 lock_start, lock_end, GFP_NOFS);
7064 btrfs_start_ordered_extent(inode, ordered, 1);
7065 btrfs_put_ordered_extent(ordered);
7066 key.offset += num_bytes;
7070 btrfs_put_ordered_extent(ordered);
7076 if (nr_extents == 1) {
7077 /* update extent pointer in place */
7078 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7079 new_extents[0].disk_bytenr);
7080 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7081 new_extents[0].disk_num_bytes);
7082 btrfs_mark_buffer_dirty(leaf);
7084 btrfs_drop_extent_cache(inode, key.offset,
7085 key.offset + num_bytes - 1, 0);
7087 ret = btrfs_inc_extent_ref(trans, root,
7088 new_extents[0].disk_bytenr,
7089 new_extents[0].disk_num_bytes,
7091 root->root_key.objectid,
7096 ret = btrfs_free_extent(trans, root,
7097 extent_key->objectid,
7100 btrfs_header_owner(leaf),
7101 btrfs_header_generation(leaf),
7105 btrfs_release_path(root, path);
7106 key.offset += num_bytes;
7114 * drop old extent pointer at first, then insert the
7115 * new pointers one bye one
7117 btrfs_release_path(root, path);
7118 ret = btrfs_drop_extents(trans, root, inode, key.offset,
7119 key.offset + num_bytes,
7120 key.offset, &alloc_hint);
7123 for (i = 0; i < nr_extents; i++) {
7124 if (ext_offset >= new_extents[i].num_bytes) {
7125 ext_offset -= new_extents[i].num_bytes;
7128 extent_len = min(new_extents[i].num_bytes -
7129 ext_offset, num_bytes);
7131 ret = btrfs_insert_empty_item(trans, root,
7136 leaf = path->nodes[0];
7137 fi = btrfs_item_ptr(leaf, path->slots[0],
7138 struct btrfs_file_extent_item);
7139 btrfs_set_file_extent_generation(leaf, fi,
7141 btrfs_set_file_extent_type(leaf, fi,
7142 BTRFS_FILE_EXTENT_REG);
7143 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7144 new_extents[i].disk_bytenr);
7145 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7146 new_extents[i].disk_num_bytes);
7147 btrfs_set_file_extent_ram_bytes(leaf, fi,
7148 new_extents[i].ram_bytes);
7150 btrfs_set_file_extent_compression(leaf, fi,
7151 new_extents[i].compression);
7152 btrfs_set_file_extent_encryption(leaf, fi,
7153 new_extents[i].encryption);
7154 btrfs_set_file_extent_other_encoding(leaf, fi,
7155 new_extents[i].other_encoding);
7157 btrfs_set_file_extent_num_bytes(leaf, fi,
7159 ext_offset += new_extents[i].offset;
7160 btrfs_set_file_extent_offset(leaf, fi,
7162 btrfs_mark_buffer_dirty(leaf);
7164 btrfs_drop_extent_cache(inode, key.offset,
7165 key.offset + extent_len - 1, 0);
7167 ret = btrfs_inc_extent_ref(trans, root,
7168 new_extents[i].disk_bytenr,
7169 new_extents[i].disk_num_bytes,
7171 root->root_key.objectid,
7172 trans->transid, key.objectid);
7174 btrfs_release_path(root, path);
7176 inode_add_bytes(inode, extent_len);
7179 num_bytes -= extent_len;
7180 key.offset += extent_len;
7185 BUG_ON(i >= nr_extents);
7189 if (extent_locked) {
7190 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7191 lock_end, GFP_NOFS);
7195 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
7196 key.offset >= search_end)
7203 btrfs_release_path(root, path);
7205 mutex_unlock(&inode->i_mutex);
7206 if (extent_locked) {
7207 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7208 lock_end, GFP_NOFS);
7215 int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
7216 struct btrfs_root *root,
7217 struct extent_buffer *buf, u64 orig_start)
7222 BUG_ON(btrfs_header_generation(buf) != trans->transid);
7223 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
7225 level = btrfs_header_level(buf);
7227 struct btrfs_leaf_ref *ref;
7228 struct btrfs_leaf_ref *orig_ref;
7230 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
7234 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
7236 btrfs_free_leaf_ref(root, orig_ref);
7240 ref->nritems = orig_ref->nritems;
7241 memcpy(ref->extents, orig_ref->extents,
7242 sizeof(ref->extents[0]) * ref->nritems);
7244 btrfs_free_leaf_ref(root, orig_ref);
7246 ref->root_gen = trans->transid;
7247 ref->bytenr = buf->start;
7248 ref->owner = btrfs_header_owner(buf);
7249 ref->generation = btrfs_header_generation(buf);
7251 ret = btrfs_add_leaf_ref(root, ref, 0);
7253 btrfs_free_leaf_ref(root, ref);
7258 static noinline int invalidate_extent_cache(struct btrfs_root *root,
7259 struct extent_buffer *leaf,
7260 struct btrfs_block_group_cache *group,
7261 struct btrfs_root *target_root)
7263 struct btrfs_key key;
7264 struct inode *inode = NULL;
7265 struct btrfs_file_extent_item *fi;
7266 struct extent_state *cached_state = NULL;
7268 u64 skip_objectid = 0;
7272 nritems = btrfs_header_nritems(leaf);
7273 for (i = 0; i < nritems; i++) {
7274 btrfs_item_key_to_cpu(leaf, &key, i);
7275 if (key.objectid == skip_objectid ||
7276 key.type != BTRFS_EXTENT_DATA_KEY)
7278 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7279 if (btrfs_file_extent_type(leaf, fi) ==
7280 BTRFS_FILE_EXTENT_INLINE)
7282 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
7284 if (!inode || inode->i_ino != key.objectid) {
7286 inode = btrfs_ilookup(target_root->fs_info->sb,
7287 key.objectid, target_root, 1);
7290 skip_objectid = key.objectid;
7293 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7295 lock_extent_bits(&BTRFS_I(inode)->io_tree, key.offset,
7296 key.offset + num_bytes - 1, 0, &cached_state,
7298 btrfs_drop_extent_cache(inode, key.offset,
7299 key.offset + num_bytes - 1, 1);
7300 unlock_extent_cached(&BTRFS_I(inode)->io_tree, key.offset,
7301 key.offset + num_bytes - 1, &cached_state,
7309 static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
7310 struct btrfs_root *root,
7311 struct extent_buffer *leaf,
7312 struct btrfs_block_group_cache *group,
7313 struct inode *reloc_inode)
7315 struct btrfs_key key;
7316 struct btrfs_key extent_key;
7317 struct btrfs_file_extent_item *fi;
7318 struct btrfs_leaf_ref *ref;
7319 struct disk_extent *new_extent;
7328 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
7329 BUG_ON(!new_extent);
7331 ref = btrfs_lookup_leaf_ref(root, leaf->start);
7335 nritems = btrfs_header_nritems(leaf);
7336 for (i = 0; i < nritems; i++) {
7337 btrfs_item_key_to_cpu(leaf, &key, i);
7338 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
7340 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7341 if (btrfs_file_extent_type(leaf, fi) ==
7342 BTRFS_FILE_EXTENT_INLINE)
7344 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
7345 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
7350 if (bytenr >= group->key.objectid + group->key.offset ||
7351 bytenr + num_bytes <= group->key.objectid)
7354 extent_key.objectid = bytenr;
7355 extent_key.offset = num_bytes;
7356 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
7358 ret = get_new_locations(reloc_inode, &extent_key,
7359 group->key.objectid, 1,
7360 &new_extent, &nr_extent);
7365 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
7366 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
7367 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
7368 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
7370 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7371 new_extent->disk_bytenr);
7372 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7373 new_extent->disk_num_bytes);
7374 btrfs_mark_buffer_dirty(leaf);
7376 ret = btrfs_inc_extent_ref(trans, root,
7377 new_extent->disk_bytenr,
7378 new_extent->disk_num_bytes,
7380 root->root_key.objectid,
7381 trans->transid, key.objectid);
7384 ret = btrfs_free_extent(trans, root,
7385 bytenr, num_bytes, leaf->start,
7386 btrfs_header_owner(leaf),
7387 btrfs_header_generation(leaf),
7393 BUG_ON(ext_index + 1 != ref->nritems);
7394 btrfs_free_leaf_ref(root, ref);
7398 int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
7399 struct btrfs_root *root)
7401 struct btrfs_root *reloc_root;
7404 if (root->reloc_root) {
7405 reloc_root = root->reloc_root;
7406 root->reloc_root = NULL;
7407 list_add(&reloc_root->dead_list,
7408 &root->fs_info->dead_reloc_roots);
7410 btrfs_set_root_bytenr(&reloc_root->root_item,
7411 reloc_root->node->start);
7412 btrfs_set_root_level(&root->root_item,
7413 btrfs_header_level(reloc_root->node));
7414 memset(&reloc_root->root_item.drop_progress, 0,
7415 sizeof(struct btrfs_disk_key));
7416 reloc_root->root_item.drop_level = 0;
7418 ret = btrfs_update_root(trans, root->fs_info->tree_root,
7419 &reloc_root->root_key,
7420 &reloc_root->root_item);
7426 int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
7428 struct btrfs_trans_handle *trans;
7429 struct btrfs_root *reloc_root;
7430 struct btrfs_root *prev_root = NULL;
7431 struct list_head dead_roots;
7435 INIT_LIST_HEAD(&dead_roots);
7436 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
7438 while (!list_empty(&dead_roots)) {
7439 reloc_root = list_entry(dead_roots.prev,
7440 struct btrfs_root, dead_list);
7441 list_del_init(&reloc_root->dead_list);
7443 BUG_ON(reloc_root->commit_root != NULL);
7445 trans = btrfs_join_transaction(root, 1);
7448 mutex_lock(&root->fs_info->drop_mutex);
7449 ret = btrfs_drop_snapshot(trans, reloc_root);
7452 mutex_unlock(&root->fs_info->drop_mutex);
7454 nr = trans->blocks_used;
7455 ret = btrfs_end_transaction(trans, root);
7457 btrfs_btree_balance_dirty(root, nr);
7460 free_extent_buffer(reloc_root->node);
7462 ret = btrfs_del_root(trans, root->fs_info->tree_root,
7463 &reloc_root->root_key);
7465 mutex_unlock(&root->fs_info->drop_mutex);
7467 nr = trans->blocks_used;
7468 ret = btrfs_end_transaction(trans, root);
7470 btrfs_btree_balance_dirty(root, nr);
7473 prev_root = reloc_root;
7476 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
7482 int btrfs_add_dead_reloc_root(struct btrfs_root *root)
7484 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
7488 int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
7490 struct btrfs_root *reloc_root;
7491 struct btrfs_trans_handle *trans;
7492 struct btrfs_key location;
7496 mutex_lock(&root->fs_info->tree_reloc_mutex);
7497 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
7499 found = !list_empty(&root->fs_info->dead_reloc_roots);
7500 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7503 trans = btrfs_start_transaction(root, 1);
7505 ret = btrfs_commit_transaction(trans, root);
7509 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
7510 location.offset = (u64)-1;
7511 location.type = BTRFS_ROOT_ITEM_KEY;
7513 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
7514 BUG_ON(!reloc_root);
7515 btrfs_orphan_cleanup(reloc_root);
7519 static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
7520 struct btrfs_root *root)
7522 struct btrfs_root *reloc_root;
7523 struct extent_buffer *eb;
7524 struct btrfs_root_item *root_item;
7525 struct btrfs_key root_key;
7528 BUG_ON(!root->ref_cows);
7529 if (root->reloc_root)
7532 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
7535 ret = btrfs_copy_root(trans, root, root->commit_root,
7536 &eb, BTRFS_TREE_RELOC_OBJECTID);
7539 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
7540 root_key.offset = root->root_key.objectid;
7541 root_key.type = BTRFS_ROOT_ITEM_KEY;
7543 memcpy(root_item, &root->root_item, sizeof(root_item));
7544 btrfs_set_root_refs(root_item, 0);
7545 btrfs_set_root_bytenr(root_item, eb->start);
7546 btrfs_set_root_level(root_item, btrfs_header_level(eb));
7547 btrfs_set_root_generation(root_item, trans->transid);
7549 btrfs_tree_unlock(eb);
7550 free_extent_buffer(eb);
7552 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
7553 &root_key, root_item);
7557 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
7559 BUG_ON(!reloc_root);
7560 reloc_root->last_trans = trans->transid;
7561 reloc_root->commit_root = NULL;
7562 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
7564 root->reloc_root = reloc_root;
7569 * Core function of space balance.
7571 * The idea is using reloc trees to relocate tree blocks in reference
7572 * counted roots. There is one reloc tree for each subvol, and all
7573 * reloc trees share same root key objectid. Reloc trees are snapshots
7574 * of the latest committed roots of subvols (root->commit_root).
7576 * To relocate a tree block referenced by a subvol, there are two steps.
7577 * COW the block through subvol's reloc tree, then update block pointer
7578 * in the subvol to point to the new block. Since all reloc trees share
7579 * same root key objectid, doing special handing for tree blocks owned
7580 * by them is easy. Once a tree block has been COWed in one reloc tree,
7581 * we can use the resulting new block directly when the same block is
7582 * required to COW again through other reloc trees. By this way, relocated
7583 * tree blocks are shared between reloc trees, so they are also shared
7586 static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
7587 struct btrfs_root *root,
7588 struct btrfs_path *path,
7589 struct btrfs_key *first_key,
7590 struct btrfs_ref_path *ref_path,
7591 struct btrfs_block_group_cache *group,
7592 struct inode *reloc_inode)
7594 struct btrfs_root *reloc_root;
7595 struct extent_buffer *eb = NULL;
7596 struct btrfs_key *keys;
7600 int lowest_level = 0;
7603 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
7604 lowest_level = ref_path->owner_objectid;
7606 if (!root->ref_cows) {
7607 path->lowest_level = lowest_level;
7608 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
7610 path->lowest_level = 0;
7611 btrfs_release_path(root, path);
7615 mutex_lock(&root->fs_info->tree_reloc_mutex);
7616 ret = init_reloc_tree(trans, root);
7618 reloc_root = root->reloc_root;
7620 shared_level = ref_path->shared_level;
7621 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
7623 keys = ref_path->node_keys;
7624 nodes = ref_path->new_nodes;
7625 memset(&keys[shared_level + 1], 0,
7626 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
7627 memset(&nodes[shared_level + 1], 0,
7628 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
7630 if (nodes[lowest_level] == 0) {
7631 path->lowest_level = lowest_level;
7632 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7635 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
7636 eb = path->nodes[level];
7637 if (!eb || eb == reloc_root->node)
7639 nodes[level] = eb->start;
7641 btrfs_item_key_to_cpu(eb, &keys[level], 0);
7643 btrfs_node_key_to_cpu(eb, &keys[level], 0);
7646 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7647 eb = path->nodes[0];
7648 ret = replace_extents_in_leaf(trans, reloc_root, eb,
7649 group, reloc_inode);
7652 btrfs_release_path(reloc_root, path);
7654 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
7660 * replace tree blocks in the fs tree with tree blocks in
7663 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
7666 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7667 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7670 extent_buffer_get(path->nodes[0]);
7671 eb = path->nodes[0];
7672 btrfs_release_path(reloc_root, path);
7673 ret = invalidate_extent_cache(reloc_root, eb, group, root);
7675 free_extent_buffer(eb);
7678 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7679 path->lowest_level = 0;
7683 static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
7684 struct btrfs_root *root,
7685 struct btrfs_path *path,
7686 struct btrfs_key *first_key,
7687 struct btrfs_ref_path *ref_path)
7691 ret = relocate_one_path(trans, root, path, first_key,
7692 ref_path, NULL, NULL);
7698 static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
7699 struct btrfs_root *extent_root,
7700 struct btrfs_path *path,
7701 struct btrfs_key *extent_key)
7705 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
7708 ret = btrfs_del_item(trans, extent_root, path);
7710 btrfs_release_path(extent_root, path);
7714 static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
7715 struct btrfs_ref_path *ref_path)
7717 struct btrfs_key root_key;
7719 root_key.objectid = ref_path->root_objectid;
7720 root_key.type = BTRFS_ROOT_ITEM_KEY;
7721 if (is_cowonly_root(ref_path->root_objectid))
7722 root_key.offset = 0;
7724 root_key.offset = (u64)-1;
7726 return btrfs_read_fs_root_no_name(fs_info, &root_key);
7729 static noinline int relocate_one_extent(struct btrfs_root *extent_root,
7730 struct btrfs_path *path,
7731 struct btrfs_key *extent_key,
7732 struct btrfs_block_group_cache *group,
7733 struct inode *reloc_inode, int pass)
7735 struct btrfs_trans_handle *trans;
7736 struct btrfs_root *found_root;
7737 struct btrfs_ref_path *ref_path = NULL;
7738 struct disk_extent *new_extents = NULL;
7743 struct btrfs_key first_key;
7747 trans = btrfs_start_transaction(extent_root, 1);
7750 if (extent_key->objectid == 0) {
7751 ret = del_extent_zero(trans, extent_root, path, extent_key);
7755 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
7761 for (loops = 0; ; loops++) {
7763 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
7764 extent_key->objectid);
7766 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
7773 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
7774 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
7777 found_root = read_ref_root(extent_root->fs_info, ref_path);
7778 BUG_ON(!found_root);
7780 * for reference counted tree, only process reference paths
7781 * rooted at the latest committed root.
7783 if (found_root->ref_cows &&
7784 ref_path->root_generation != found_root->root_key.offset)
7787 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7790 * copy data extents to new locations
7792 u64 group_start = group->key.objectid;
7793 ret = relocate_data_extent(reloc_inode,
7802 level = ref_path->owner_objectid;
7805 if (prev_block != ref_path->nodes[level]) {
7806 struct extent_buffer *eb;
7807 u64 block_start = ref_path->nodes[level];
7808 u64 block_size = btrfs_level_size(found_root, level);
7810 eb = read_tree_block(found_root, block_start,
7812 btrfs_tree_lock(eb);
7813 BUG_ON(level != btrfs_header_level(eb));
7816 btrfs_item_key_to_cpu(eb, &first_key, 0);
7818 btrfs_node_key_to_cpu(eb, &first_key, 0);
7820 btrfs_tree_unlock(eb);
7821 free_extent_buffer(eb);
7822 prev_block = block_start;
7825 mutex_lock(&extent_root->fs_info->trans_mutex);
7826 btrfs_record_root_in_trans(found_root);
7827 mutex_unlock(&extent_root->fs_info->trans_mutex);
7828 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7830 * try to update data extent references while
7831 * keeping metadata shared between snapshots.
7834 ret = relocate_one_path(trans, found_root,
7835 path, &first_key, ref_path,
7836 group, reloc_inode);
7842 * use fallback method to process the remaining
7846 u64 group_start = group->key.objectid;
7847 new_extents = kmalloc(sizeof(*new_extents),
7850 ret = get_new_locations(reloc_inode,
7858 ret = replace_one_extent(trans, found_root,
7860 &first_key, ref_path,
7861 new_extents, nr_extents);
7863 ret = relocate_tree_block(trans, found_root, path,
7864 &first_key, ref_path);
7871 btrfs_end_transaction(trans, extent_root);
7878 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
7881 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
7882 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
7884 num_devices = root->fs_info->fs_devices->rw_devices;
7885 if (num_devices == 1) {
7886 stripped |= BTRFS_BLOCK_GROUP_DUP;
7887 stripped = flags & ~stripped;
7889 /* turn raid0 into single device chunks */
7890 if (flags & BTRFS_BLOCK_GROUP_RAID0)
7893 /* turn mirroring into duplication */
7894 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
7895 BTRFS_BLOCK_GROUP_RAID10))
7896 return stripped | BTRFS_BLOCK_GROUP_DUP;
7899 /* they already had raid on here, just return */
7900 if (flags & stripped)
7903 stripped |= BTRFS_BLOCK_GROUP_DUP;
7904 stripped = flags & ~stripped;
7906 /* switch duplicated blocks with raid1 */
7907 if (flags & BTRFS_BLOCK_GROUP_DUP)
7908 return stripped | BTRFS_BLOCK_GROUP_RAID1;
7910 /* turn single device chunks into raid0 */
7911 return stripped | BTRFS_BLOCK_GROUP_RAID0;
7916 static int set_block_group_ro(struct btrfs_block_group_cache *cache)
7918 struct btrfs_space_info *sinfo = cache->space_info;
7925 spin_lock(&sinfo->lock);
7926 spin_lock(&cache->lock);
7927 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7928 cache->bytes_super - btrfs_block_group_used(&cache->item);
7930 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
7931 sinfo->bytes_may_use + sinfo->bytes_readonly +
7932 cache->reserved_pinned + num_bytes < sinfo->total_bytes) {
7933 sinfo->bytes_readonly += num_bytes;
7934 sinfo->bytes_reserved += cache->reserved_pinned;
7935 cache->reserved_pinned = 0;
7939 spin_unlock(&cache->lock);
7940 spin_unlock(&sinfo->lock);
7944 int btrfs_set_block_group_ro(struct btrfs_root *root,
7945 struct btrfs_block_group_cache *cache)
7948 struct btrfs_trans_handle *trans;
7954 trans = btrfs_join_transaction(root, 1);
7955 BUG_ON(IS_ERR(trans));
7957 alloc_flags = update_block_group_flags(root, cache->flags);
7958 if (alloc_flags != cache->flags)
7959 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
7961 ret = set_block_group_ro(cache);
7964 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
7965 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
7968 ret = set_block_group_ro(cache);
7970 btrfs_end_transaction(trans, root);
7974 int btrfs_set_block_group_rw(struct btrfs_root *root,
7975 struct btrfs_block_group_cache *cache)
7977 struct btrfs_space_info *sinfo = cache->space_info;
7982 spin_lock(&sinfo->lock);
7983 spin_lock(&cache->lock);
7984 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7985 cache->bytes_super - btrfs_block_group_used(&cache->item);
7986 sinfo->bytes_readonly -= num_bytes;
7988 spin_unlock(&cache->lock);
7989 spin_unlock(&sinfo->lock);
7994 * checks to see if its even possible to relocate this block group.
7996 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
7997 * ok to go ahead and try.
7999 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
8001 struct btrfs_block_group_cache *block_group;
8002 struct btrfs_space_info *space_info;
8003 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
8004 struct btrfs_device *device;
8008 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
8010 /* odd, couldn't find the block group, leave it alone */
8014 /* no bytes used, we're good */
8015 if (!btrfs_block_group_used(&block_group->item))
8018 space_info = block_group->space_info;
8019 spin_lock(&space_info->lock);
8021 full = space_info->full;
8024 * if this is the last block group we have in this space, we can't
8025 * relocate it unless we're able to allocate a new chunk below.
8027 * Otherwise, we need to make sure we have room in the space to handle
8028 * all of the extents from this block group. If we can, we're good
8030 if ((space_info->total_bytes != block_group->key.offset) &&
8031 (space_info->bytes_used + space_info->bytes_reserved +
8032 space_info->bytes_pinned + space_info->bytes_readonly +
8033 btrfs_block_group_used(&block_group->item) <
8034 space_info->total_bytes)) {
8035 spin_unlock(&space_info->lock);
8038 spin_unlock(&space_info->lock);
8041 * ok we don't have enough space, but maybe we have free space on our
8042 * devices to allocate new chunks for relocation, so loop through our
8043 * alloc devices and guess if we have enough space. However, if we
8044 * were marked as full, then we know there aren't enough chunks, and we
8051 mutex_lock(&root->fs_info->chunk_mutex);
8052 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
8053 u64 min_free = btrfs_block_group_used(&block_group->item);
8054 u64 dev_offset, max_avail;
8057 * check to make sure we can actually find a chunk with enough
8058 * space to fit our block group in.
8060 if (device->total_bytes > device->bytes_used + min_free) {
8061 ret = find_free_dev_extent(NULL, device, min_free,
8062 &dev_offset, &max_avail);
8068 mutex_unlock(&root->fs_info->chunk_mutex);
8070 btrfs_put_block_group(block_group);
8074 static int find_first_block_group(struct btrfs_root *root,
8075 struct btrfs_path *path, struct btrfs_key *key)
8078 struct btrfs_key found_key;
8079 struct extent_buffer *leaf;
8082 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
8087 slot = path->slots[0];
8088 leaf = path->nodes[0];
8089 if (slot >= btrfs_header_nritems(leaf)) {
8090 ret = btrfs_next_leaf(root, path);
8097 btrfs_item_key_to_cpu(leaf, &found_key, slot);
8099 if (found_key.objectid >= key->objectid &&
8100 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
8110 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
8112 struct btrfs_block_group_cache *block_group;
8116 struct inode *inode;
8118 block_group = btrfs_lookup_first_block_group(info, last);
8119 while (block_group) {
8120 spin_lock(&block_group->lock);
8121 if (block_group->iref)
8123 spin_unlock(&block_group->lock);
8124 block_group = next_block_group(info->tree_root,
8134 inode = block_group->inode;
8135 block_group->iref = 0;
8136 block_group->inode = NULL;
8137 spin_unlock(&block_group->lock);
8139 last = block_group->key.objectid + block_group->key.offset;
8140 btrfs_put_block_group(block_group);
8144 int btrfs_free_block_groups(struct btrfs_fs_info *info)
8146 struct btrfs_block_group_cache *block_group;
8147 struct btrfs_space_info *space_info;
8148 struct btrfs_caching_control *caching_ctl;
8151 down_write(&info->extent_commit_sem);
8152 while (!list_empty(&info->caching_block_groups)) {
8153 caching_ctl = list_entry(info->caching_block_groups.next,
8154 struct btrfs_caching_control, list);
8155 list_del(&caching_ctl->list);
8156 put_caching_control(caching_ctl);
8158 up_write(&info->extent_commit_sem);
8160 spin_lock(&info->block_group_cache_lock);
8161 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
8162 block_group = rb_entry(n, struct btrfs_block_group_cache,
8164 rb_erase(&block_group->cache_node,
8165 &info->block_group_cache_tree);
8166 spin_unlock(&info->block_group_cache_lock);
8168 down_write(&block_group->space_info->groups_sem);
8169 list_del(&block_group->list);
8170 up_write(&block_group->space_info->groups_sem);
8172 if (block_group->cached == BTRFS_CACHE_STARTED)
8173 wait_block_group_cache_done(block_group);
8175 btrfs_remove_free_space_cache(block_group);
8176 btrfs_put_block_group(block_group);
8178 spin_lock(&info->block_group_cache_lock);
8180 spin_unlock(&info->block_group_cache_lock);
8182 /* now that all the block groups are freed, go through and
8183 * free all the space_info structs. This is only called during
8184 * the final stages of unmount, and so we know nobody is
8185 * using them. We call synchronize_rcu() once before we start,
8186 * just to be on the safe side.
8190 release_global_block_rsv(info);
8192 while(!list_empty(&info->space_info)) {
8193 space_info = list_entry(info->space_info.next,
8194 struct btrfs_space_info,
8196 if (space_info->bytes_pinned > 0 ||
8197 space_info->bytes_reserved > 0) {
8199 dump_space_info(space_info, 0, 0);
8201 list_del(&space_info->list);
8207 static void __link_block_group(struct btrfs_space_info *space_info,
8208 struct btrfs_block_group_cache *cache)
8210 int index = get_block_group_index(cache);
8212 down_write(&space_info->groups_sem);
8213 list_add_tail(&cache->list, &space_info->block_groups[index]);
8214 up_write(&space_info->groups_sem);
8217 int btrfs_read_block_groups(struct btrfs_root *root)
8219 struct btrfs_path *path;
8221 struct btrfs_block_group_cache *cache;
8222 struct btrfs_fs_info *info = root->fs_info;
8223 struct btrfs_space_info *space_info;
8224 struct btrfs_key key;
8225 struct btrfs_key found_key;
8226 struct extent_buffer *leaf;
8230 root = info->extent_root;
8233 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
8234 path = btrfs_alloc_path();
8238 cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy);
8239 if (cache_gen != 0 &&
8240 btrfs_super_generation(&root->fs_info->super_copy) != cache_gen)
8242 if (btrfs_test_opt(root, CLEAR_CACHE))
8244 if (!btrfs_test_opt(root, SPACE_CACHE) && cache_gen)
8245 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
8248 ret = find_first_block_group(root, path, &key);
8254 leaf = path->nodes[0];
8255 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
8256 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8262 atomic_set(&cache->count, 1);
8263 spin_lock_init(&cache->lock);
8264 spin_lock_init(&cache->tree_lock);
8265 cache->fs_info = info;
8266 INIT_LIST_HEAD(&cache->list);
8267 INIT_LIST_HEAD(&cache->cluster_list);
8270 cache->disk_cache_state = BTRFS_DC_CLEAR;
8273 * we only want to have 32k of ram per block group for keeping
8274 * track of free space, and if we pass 1/2 of that we want to
8275 * start converting things over to using bitmaps
8277 cache->extents_thresh = ((1024 * 32) / 2) /
8278 sizeof(struct btrfs_free_space);
8280 read_extent_buffer(leaf, &cache->item,
8281 btrfs_item_ptr_offset(leaf, path->slots[0]),
8282 sizeof(cache->item));
8283 memcpy(&cache->key, &found_key, sizeof(found_key));
8285 key.objectid = found_key.objectid + found_key.offset;
8286 btrfs_release_path(root, path);
8287 cache->flags = btrfs_block_group_flags(&cache->item);
8288 cache->sectorsize = root->sectorsize;
8291 * check for two cases, either we are full, and therefore
8292 * don't need to bother with the caching work since we won't
8293 * find any space, or we are empty, and we can just add all
8294 * the space in and be done with it. This saves us _alot_ of
8295 * time, particularly in the full case.
8297 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
8298 exclude_super_stripes(root, cache);
8299 cache->last_byte_to_unpin = (u64)-1;
8300 cache->cached = BTRFS_CACHE_FINISHED;
8301 free_excluded_extents(root, cache);
8302 } else if (btrfs_block_group_used(&cache->item) == 0) {
8303 exclude_super_stripes(root, cache);
8304 cache->last_byte_to_unpin = (u64)-1;
8305 cache->cached = BTRFS_CACHE_FINISHED;
8306 add_new_free_space(cache, root->fs_info,
8308 found_key.objectid +
8310 free_excluded_extents(root, cache);
8313 ret = update_space_info(info, cache->flags, found_key.offset,
8314 btrfs_block_group_used(&cache->item),
8317 cache->space_info = space_info;
8318 spin_lock(&cache->space_info->lock);
8319 cache->space_info->bytes_readonly += cache->bytes_super;
8320 spin_unlock(&cache->space_info->lock);
8322 __link_block_group(space_info, cache);
8324 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8327 set_avail_alloc_bits(root->fs_info, cache->flags);
8328 if (btrfs_chunk_readonly(root, cache->key.objectid))
8329 set_block_group_ro(cache);
8332 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
8333 if (!(get_alloc_profile(root, space_info->flags) &
8334 (BTRFS_BLOCK_GROUP_RAID10 |
8335 BTRFS_BLOCK_GROUP_RAID1 |
8336 BTRFS_BLOCK_GROUP_DUP)))
8339 * avoid allocating from un-mirrored block group if there are
8340 * mirrored block groups.
8342 list_for_each_entry(cache, &space_info->block_groups[3], list)
8343 set_block_group_ro(cache);
8344 list_for_each_entry(cache, &space_info->block_groups[4], list)
8345 set_block_group_ro(cache);
8348 init_global_block_rsv(info);
8351 btrfs_free_path(path);
8355 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
8356 struct btrfs_root *root, u64 bytes_used,
8357 u64 type, u64 chunk_objectid, u64 chunk_offset,
8361 struct btrfs_root *extent_root;
8362 struct btrfs_block_group_cache *cache;
8364 extent_root = root->fs_info->extent_root;
8366 root->fs_info->last_trans_log_full_commit = trans->transid;
8368 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8372 cache->key.objectid = chunk_offset;
8373 cache->key.offset = size;
8374 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
8375 cache->sectorsize = root->sectorsize;
8376 cache->fs_info = root->fs_info;
8379 * we only want to have 32k of ram per block group for keeping track
8380 * of free space, and if we pass 1/2 of that we want to start
8381 * converting things over to using bitmaps
8383 cache->extents_thresh = ((1024 * 32) / 2) /
8384 sizeof(struct btrfs_free_space);
8385 atomic_set(&cache->count, 1);
8386 spin_lock_init(&cache->lock);
8387 spin_lock_init(&cache->tree_lock);
8388 INIT_LIST_HEAD(&cache->list);
8389 INIT_LIST_HEAD(&cache->cluster_list);
8391 btrfs_set_block_group_used(&cache->item, bytes_used);
8392 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
8393 cache->flags = type;
8394 btrfs_set_block_group_flags(&cache->item, type);
8396 cache->last_byte_to_unpin = (u64)-1;
8397 cache->cached = BTRFS_CACHE_FINISHED;
8398 exclude_super_stripes(root, cache);
8400 add_new_free_space(cache, root->fs_info, chunk_offset,
8401 chunk_offset + size);
8403 free_excluded_extents(root, cache);
8405 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
8406 &cache->space_info);
8409 spin_lock(&cache->space_info->lock);
8410 cache->space_info->bytes_readonly += cache->bytes_super;
8411 spin_unlock(&cache->space_info->lock);
8413 __link_block_group(cache->space_info, cache);
8415 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8418 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
8419 sizeof(cache->item));
8422 set_avail_alloc_bits(extent_root->fs_info, type);
8427 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
8428 struct btrfs_root *root, u64 group_start)
8430 struct btrfs_path *path;
8431 struct btrfs_block_group_cache *block_group;
8432 struct btrfs_free_cluster *cluster;
8433 struct btrfs_root *tree_root = root->fs_info->tree_root;
8434 struct btrfs_key key;
8435 struct inode *inode;
8439 root = root->fs_info->extent_root;
8441 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
8442 BUG_ON(!block_group);
8443 BUG_ON(!block_group->ro);
8445 memcpy(&key, &block_group->key, sizeof(key));
8446 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
8447 BTRFS_BLOCK_GROUP_RAID1 |
8448 BTRFS_BLOCK_GROUP_RAID10))
8453 /* make sure this block group isn't part of an allocation cluster */
8454 cluster = &root->fs_info->data_alloc_cluster;
8455 spin_lock(&cluster->refill_lock);
8456 btrfs_return_cluster_to_free_space(block_group, cluster);
8457 spin_unlock(&cluster->refill_lock);
8460 * make sure this block group isn't part of a metadata
8461 * allocation cluster
8463 cluster = &root->fs_info->meta_alloc_cluster;
8464 spin_lock(&cluster->refill_lock);
8465 btrfs_return_cluster_to_free_space(block_group, cluster);
8466 spin_unlock(&cluster->refill_lock);
8468 path = btrfs_alloc_path();
8471 inode = lookup_free_space_inode(root, block_group, path);
8472 if (!IS_ERR(inode)) {
8473 btrfs_orphan_add(trans, inode);
8475 /* One for the block groups ref */
8476 spin_lock(&block_group->lock);
8477 if (block_group->iref) {
8478 block_group->iref = 0;
8479 block_group->inode = NULL;
8480 spin_unlock(&block_group->lock);
8483 spin_unlock(&block_group->lock);
8485 /* One for our lookup ref */
8489 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
8490 key.offset = block_group->key.objectid;
8493 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
8497 btrfs_release_path(tree_root, path);
8499 ret = btrfs_del_item(trans, tree_root, path);
8502 btrfs_release_path(tree_root, path);
8505 spin_lock(&root->fs_info->block_group_cache_lock);
8506 rb_erase(&block_group->cache_node,
8507 &root->fs_info->block_group_cache_tree);
8508 spin_unlock(&root->fs_info->block_group_cache_lock);
8510 down_write(&block_group->space_info->groups_sem);
8512 * we must use list_del_init so people can check to see if they
8513 * are still on the list after taking the semaphore
8515 list_del_init(&block_group->list);
8516 up_write(&block_group->space_info->groups_sem);
8518 if (block_group->cached == BTRFS_CACHE_STARTED)
8519 wait_block_group_cache_done(block_group);
8521 btrfs_remove_free_space_cache(block_group);
8523 spin_lock(&block_group->space_info->lock);
8524 block_group->space_info->total_bytes -= block_group->key.offset;
8525 block_group->space_info->bytes_readonly -= block_group->key.offset;
8526 block_group->space_info->disk_total -= block_group->key.offset * factor;
8527 spin_unlock(&block_group->space_info->lock);
8529 memcpy(&key, &block_group->key, sizeof(key));
8531 btrfs_clear_space_info_full(root->fs_info);
8533 btrfs_put_block_group(block_group);
8534 btrfs_put_block_group(block_group);
8536 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8542 ret = btrfs_del_item(trans, root, path);
8544 btrfs_free_path(path);