2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
18 #include <linux/sched.h>
19 #include <linux/pagemap.h>
20 #include <linux/writeback.h>
21 #include <linux/blkdev.h>
22 #include <linux/sort.h>
23 #include <linux/rcupdate.h>
24 #include <linux/kthread.h>
25 #include <linux/slab.h>
26 #include <linux/ratelimit.h>
31 #include "print-tree.h"
32 #include "transaction.h"
35 #include "free-space-cache.h"
37 /* control flags for do_chunk_alloc's force field
38 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
39 * if we really need one.
41 * CHUNK_ALLOC_FORCE means it must try to allocate one
43 * CHUNK_ALLOC_LIMITED means to only try and allocate one
44 * if we have very few chunks already allocated. This is
45 * used as part of the clustering code to help make sure
46 * we have a good pool of storage to cluster in, without
47 * filling the FS with empty chunks
51 CHUNK_ALLOC_NO_FORCE = 0,
52 CHUNK_ALLOC_FORCE = 1,
53 CHUNK_ALLOC_LIMITED = 2,
57 * Control how reservations are dealt with.
59 * RESERVE_FREE - freeing a reservation.
60 * RESERVE_ALLOC - allocating space and we need to update bytes_may_use for
62 * RESERVE_ALLOC_NO_ACCOUNT - allocating space and we should not update
63 * bytes_may_use as the ENOSPC accounting is done elsewhere
68 RESERVE_ALLOC_NO_ACCOUNT = 2,
71 static int update_block_group(struct btrfs_trans_handle *trans,
72 struct btrfs_root *root,
73 u64 bytenr, u64 num_bytes, int alloc);
74 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
75 struct btrfs_root *root,
76 u64 bytenr, u64 num_bytes, u64 parent,
77 u64 root_objectid, u64 owner_objectid,
78 u64 owner_offset, int refs_to_drop,
79 struct btrfs_delayed_extent_op *extra_op);
80 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
81 struct extent_buffer *leaf,
82 struct btrfs_extent_item *ei);
83 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
84 struct btrfs_root *root,
85 u64 parent, u64 root_objectid,
86 u64 flags, u64 owner, u64 offset,
87 struct btrfs_key *ins, int ref_mod);
88 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
89 struct btrfs_root *root,
90 u64 parent, u64 root_objectid,
91 u64 flags, struct btrfs_disk_key *key,
92 int level, struct btrfs_key *ins);
93 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
94 struct btrfs_root *extent_root, u64 alloc_bytes,
95 u64 flags, int force);
96 static int find_next_key(struct btrfs_path *path, int level,
97 struct btrfs_key *key);
98 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
99 int dump_block_groups);
100 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
101 u64 num_bytes, int reserve);
104 block_group_cache_done(struct btrfs_block_group_cache *cache)
107 return cache->cached == BTRFS_CACHE_FINISHED;
110 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
112 return (cache->flags & bits) == bits;
115 static void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
117 atomic_inc(&cache->count);
120 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
122 if (atomic_dec_and_test(&cache->count)) {
123 WARN_ON(cache->pinned > 0);
124 WARN_ON(cache->reserved > 0);
125 kfree(cache->free_space_ctl);
131 * this adds the block group to the fs_info rb tree for the block group
134 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
135 struct btrfs_block_group_cache *block_group)
138 struct rb_node *parent = NULL;
139 struct btrfs_block_group_cache *cache;
141 spin_lock(&info->block_group_cache_lock);
142 p = &info->block_group_cache_tree.rb_node;
146 cache = rb_entry(parent, struct btrfs_block_group_cache,
148 if (block_group->key.objectid < cache->key.objectid) {
150 } else if (block_group->key.objectid > cache->key.objectid) {
153 spin_unlock(&info->block_group_cache_lock);
158 rb_link_node(&block_group->cache_node, parent, p);
159 rb_insert_color(&block_group->cache_node,
160 &info->block_group_cache_tree);
161 spin_unlock(&info->block_group_cache_lock);
167 * This will return the block group at or after bytenr if contains is 0, else
168 * it will return the block group that contains the bytenr
170 static struct btrfs_block_group_cache *
171 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
174 struct btrfs_block_group_cache *cache, *ret = NULL;
178 spin_lock(&info->block_group_cache_lock);
179 n = info->block_group_cache_tree.rb_node;
182 cache = rb_entry(n, struct btrfs_block_group_cache,
184 end = cache->key.objectid + cache->key.offset - 1;
185 start = cache->key.objectid;
187 if (bytenr < start) {
188 if (!contains && (!ret || start < ret->key.objectid))
191 } else if (bytenr > start) {
192 if (contains && bytenr <= end) {
203 btrfs_get_block_group(ret);
204 spin_unlock(&info->block_group_cache_lock);
209 static int add_excluded_extent(struct btrfs_root *root,
210 u64 start, u64 num_bytes)
212 u64 end = start + num_bytes - 1;
213 set_extent_bits(&root->fs_info->freed_extents[0],
214 start, end, EXTENT_UPTODATE, GFP_NOFS);
215 set_extent_bits(&root->fs_info->freed_extents[1],
216 start, end, EXTENT_UPTODATE, GFP_NOFS);
220 static void free_excluded_extents(struct btrfs_root *root,
221 struct btrfs_block_group_cache *cache)
225 start = cache->key.objectid;
226 end = start + cache->key.offset - 1;
228 clear_extent_bits(&root->fs_info->freed_extents[0],
229 start, end, EXTENT_UPTODATE, GFP_NOFS);
230 clear_extent_bits(&root->fs_info->freed_extents[1],
231 start, end, EXTENT_UPTODATE, GFP_NOFS);
234 static int exclude_super_stripes(struct btrfs_root *root,
235 struct btrfs_block_group_cache *cache)
242 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
243 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
244 cache->bytes_super += stripe_len;
245 ret = add_excluded_extent(root, cache->key.objectid,
250 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
251 bytenr = btrfs_sb_offset(i);
252 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
253 cache->key.objectid, bytenr,
254 0, &logical, &nr, &stripe_len);
258 cache->bytes_super += stripe_len;
259 ret = add_excluded_extent(root, logical[nr],
269 static struct btrfs_caching_control *
270 get_caching_control(struct btrfs_block_group_cache *cache)
272 struct btrfs_caching_control *ctl;
274 spin_lock(&cache->lock);
275 if (cache->cached != BTRFS_CACHE_STARTED) {
276 spin_unlock(&cache->lock);
280 /* We're loading it the fast way, so we don't have a caching_ctl. */
281 if (!cache->caching_ctl) {
282 spin_unlock(&cache->lock);
286 ctl = cache->caching_ctl;
287 atomic_inc(&ctl->count);
288 spin_unlock(&cache->lock);
292 static void put_caching_control(struct btrfs_caching_control *ctl)
294 if (atomic_dec_and_test(&ctl->count))
299 * this is only called by cache_block_group, since we could have freed extents
300 * we need to check the pinned_extents for any extents that can't be used yet
301 * since their free space will be released as soon as the transaction commits.
303 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
304 struct btrfs_fs_info *info, u64 start, u64 end)
306 u64 extent_start, extent_end, size, total_added = 0;
309 while (start < end) {
310 ret = find_first_extent_bit(info->pinned_extents, start,
311 &extent_start, &extent_end,
312 EXTENT_DIRTY | EXTENT_UPTODATE);
316 if (extent_start <= start) {
317 start = extent_end + 1;
318 } else if (extent_start > start && extent_start < end) {
319 size = extent_start - start;
321 ret = btrfs_add_free_space(block_group, start,
324 start = extent_end + 1;
333 ret = btrfs_add_free_space(block_group, start, size);
340 static noinline void caching_thread(struct btrfs_work *work)
342 struct btrfs_block_group_cache *block_group;
343 struct btrfs_fs_info *fs_info;
344 struct btrfs_caching_control *caching_ctl;
345 struct btrfs_root *extent_root;
346 struct btrfs_path *path;
347 struct extent_buffer *leaf;
348 struct btrfs_key key;
354 caching_ctl = container_of(work, struct btrfs_caching_control, work);
355 block_group = caching_ctl->block_group;
356 fs_info = block_group->fs_info;
357 extent_root = fs_info->extent_root;
359 path = btrfs_alloc_path();
363 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
366 * We don't want to deadlock with somebody trying to allocate a new
367 * extent for the extent root while also trying to search the extent
368 * root to add free space. So we skip locking and search the commit
369 * root, since its read-only
371 path->skip_locking = 1;
372 path->search_commit_root = 1;
377 key.type = BTRFS_EXTENT_ITEM_KEY;
379 mutex_lock(&caching_ctl->mutex);
380 /* need to make sure the commit_root doesn't disappear */
381 down_read(&fs_info->extent_commit_sem);
383 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
387 leaf = path->nodes[0];
388 nritems = btrfs_header_nritems(leaf);
391 if (btrfs_fs_closing(fs_info) > 1) {
396 if (path->slots[0] < nritems) {
397 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
399 ret = find_next_key(path, 0, &key);
403 if (need_resched() ||
404 btrfs_next_leaf(extent_root, path)) {
405 caching_ctl->progress = last;
406 btrfs_release_path(path);
407 up_read(&fs_info->extent_commit_sem);
408 mutex_unlock(&caching_ctl->mutex);
412 leaf = path->nodes[0];
413 nritems = btrfs_header_nritems(leaf);
417 if (key.objectid < block_group->key.objectid) {
422 if (key.objectid >= block_group->key.objectid +
423 block_group->key.offset)
426 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
427 total_found += add_new_free_space(block_group,
430 last = key.objectid + key.offset;
432 if (total_found > (1024 * 1024 * 2)) {
434 wake_up(&caching_ctl->wait);
441 total_found += add_new_free_space(block_group, fs_info, last,
442 block_group->key.objectid +
443 block_group->key.offset);
444 caching_ctl->progress = (u64)-1;
446 spin_lock(&block_group->lock);
447 block_group->caching_ctl = NULL;
448 block_group->cached = BTRFS_CACHE_FINISHED;
449 spin_unlock(&block_group->lock);
452 btrfs_free_path(path);
453 up_read(&fs_info->extent_commit_sem);
455 free_excluded_extents(extent_root, block_group);
457 mutex_unlock(&caching_ctl->mutex);
459 wake_up(&caching_ctl->wait);
461 put_caching_control(caching_ctl);
462 btrfs_put_block_group(block_group);
465 static int cache_block_group(struct btrfs_block_group_cache *cache,
466 struct btrfs_trans_handle *trans,
467 struct btrfs_root *root,
470 struct btrfs_fs_info *fs_info = cache->fs_info;
471 struct btrfs_caching_control *caching_ctl;
475 if (cache->cached != BTRFS_CACHE_NO)
479 * We can't do the read from on-disk cache during a commit since we need
480 * to have the normal tree locking. Also if we are currently trying to
481 * allocate blocks for the tree root we can't do the fast caching since
482 * we likely hold important locks.
484 if (trans && (!trans->transaction->in_commit) &&
485 (root && root != root->fs_info->tree_root) &&
486 btrfs_test_opt(root, SPACE_CACHE)) {
487 spin_lock(&cache->lock);
488 if (cache->cached != BTRFS_CACHE_NO) {
489 spin_unlock(&cache->lock);
492 cache->cached = BTRFS_CACHE_STARTED;
493 spin_unlock(&cache->lock);
495 ret = load_free_space_cache(fs_info, cache);
497 spin_lock(&cache->lock);
499 cache->cached = BTRFS_CACHE_FINISHED;
500 cache->last_byte_to_unpin = (u64)-1;
502 cache->cached = BTRFS_CACHE_NO;
504 spin_unlock(&cache->lock);
506 free_excluded_extents(fs_info->extent_root, cache);
514 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
515 BUG_ON(!caching_ctl);
517 INIT_LIST_HEAD(&caching_ctl->list);
518 mutex_init(&caching_ctl->mutex);
519 init_waitqueue_head(&caching_ctl->wait);
520 caching_ctl->block_group = cache;
521 caching_ctl->progress = cache->key.objectid;
522 /* one for caching kthread, one for caching block group list */
523 atomic_set(&caching_ctl->count, 2);
524 caching_ctl->work.func = caching_thread;
526 spin_lock(&cache->lock);
527 if (cache->cached != BTRFS_CACHE_NO) {
528 spin_unlock(&cache->lock);
532 cache->caching_ctl = caching_ctl;
533 cache->cached = BTRFS_CACHE_STARTED;
534 spin_unlock(&cache->lock);
536 down_write(&fs_info->extent_commit_sem);
537 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
538 up_write(&fs_info->extent_commit_sem);
540 btrfs_get_block_group(cache);
542 btrfs_queue_worker(&fs_info->caching_workers, &caching_ctl->work);
548 * return the block group that starts at or after bytenr
550 static struct btrfs_block_group_cache *
551 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
553 struct btrfs_block_group_cache *cache;
555 cache = block_group_cache_tree_search(info, bytenr, 0);
561 * return the block group that contains the given bytenr
563 struct btrfs_block_group_cache *btrfs_lookup_block_group(
564 struct btrfs_fs_info *info,
567 struct btrfs_block_group_cache *cache;
569 cache = block_group_cache_tree_search(info, bytenr, 1);
574 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
577 struct list_head *head = &info->space_info;
578 struct btrfs_space_info *found;
580 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
581 BTRFS_BLOCK_GROUP_METADATA;
584 list_for_each_entry_rcu(found, head, list) {
585 if (found->flags & flags) {
595 * after adding space to the filesystem, we need to clear the full flags
596 * on all the space infos.
598 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
600 struct list_head *head = &info->space_info;
601 struct btrfs_space_info *found;
604 list_for_each_entry_rcu(found, head, list)
609 static u64 div_factor(u64 num, int factor)
618 static u64 div_factor_fine(u64 num, int factor)
627 u64 btrfs_find_block_group(struct btrfs_root *root,
628 u64 search_start, u64 search_hint, int owner)
630 struct btrfs_block_group_cache *cache;
632 u64 last = max(search_hint, search_start);
639 cache = btrfs_lookup_first_block_group(root->fs_info, last);
643 spin_lock(&cache->lock);
644 last = cache->key.objectid + cache->key.offset;
645 used = btrfs_block_group_used(&cache->item);
647 if ((full_search || !cache->ro) &&
648 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
649 if (used + cache->pinned + cache->reserved <
650 div_factor(cache->key.offset, factor)) {
651 group_start = cache->key.objectid;
652 spin_unlock(&cache->lock);
653 btrfs_put_block_group(cache);
657 spin_unlock(&cache->lock);
658 btrfs_put_block_group(cache);
666 if (!full_search && factor < 10) {
676 /* simple helper to search for an existing extent at a given offset */
677 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
680 struct btrfs_key key;
681 struct btrfs_path *path;
683 path = btrfs_alloc_path();
687 key.objectid = start;
689 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
690 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
692 btrfs_free_path(path);
697 * helper function to lookup reference count and flags of extent.
699 * the head node for delayed ref is used to store the sum of all the
700 * reference count modifications queued up in the rbtree. the head
701 * node may also store the extent flags to set. This way you can check
702 * to see what the reference count and extent flags would be if all of
703 * the delayed refs are not processed.
705 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
706 struct btrfs_root *root, u64 bytenr,
707 u64 num_bytes, u64 *refs, u64 *flags)
709 struct btrfs_delayed_ref_head *head;
710 struct btrfs_delayed_ref_root *delayed_refs;
711 struct btrfs_path *path;
712 struct btrfs_extent_item *ei;
713 struct extent_buffer *leaf;
714 struct btrfs_key key;
720 path = btrfs_alloc_path();
724 key.objectid = bytenr;
725 key.type = BTRFS_EXTENT_ITEM_KEY;
726 key.offset = num_bytes;
728 path->skip_locking = 1;
729 path->search_commit_root = 1;
732 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
738 leaf = path->nodes[0];
739 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
740 if (item_size >= sizeof(*ei)) {
741 ei = btrfs_item_ptr(leaf, path->slots[0],
742 struct btrfs_extent_item);
743 num_refs = btrfs_extent_refs(leaf, ei);
744 extent_flags = btrfs_extent_flags(leaf, ei);
746 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
747 struct btrfs_extent_item_v0 *ei0;
748 BUG_ON(item_size != sizeof(*ei0));
749 ei0 = btrfs_item_ptr(leaf, path->slots[0],
750 struct btrfs_extent_item_v0);
751 num_refs = btrfs_extent_refs_v0(leaf, ei0);
752 /* FIXME: this isn't correct for data */
753 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
758 BUG_ON(num_refs == 0);
768 delayed_refs = &trans->transaction->delayed_refs;
769 spin_lock(&delayed_refs->lock);
770 head = btrfs_find_delayed_ref_head(trans, bytenr);
772 if (!mutex_trylock(&head->mutex)) {
773 atomic_inc(&head->node.refs);
774 spin_unlock(&delayed_refs->lock);
776 btrfs_release_path(path);
779 * Mutex was contended, block until it's released and try
782 mutex_lock(&head->mutex);
783 mutex_unlock(&head->mutex);
784 btrfs_put_delayed_ref(&head->node);
787 if (head->extent_op && head->extent_op->update_flags)
788 extent_flags |= head->extent_op->flags_to_set;
790 BUG_ON(num_refs == 0);
792 num_refs += head->node.ref_mod;
793 mutex_unlock(&head->mutex);
795 spin_unlock(&delayed_refs->lock);
797 WARN_ON(num_refs == 0);
801 *flags = extent_flags;
803 btrfs_free_path(path);
808 * Back reference rules. Back refs have three main goals:
810 * 1) differentiate between all holders of references to an extent so that
811 * when a reference is dropped we can make sure it was a valid reference
812 * before freeing the extent.
814 * 2) Provide enough information to quickly find the holders of an extent
815 * if we notice a given block is corrupted or bad.
817 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
818 * maintenance. This is actually the same as #2, but with a slightly
819 * different use case.
821 * There are two kinds of back refs. The implicit back refs is optimized
822 * for pointers in non-shared tree blocks. For a given pointer in a block,
823 * back refs of this kind provide information about the block's owner tree
824 * and the pointer's key. These information allow us to find the block by
825 * b-tree searching. The full back refs is for pointers in tree blocks not
826 * referenced by their owner trees. The location of tree block is recorded
827 * in the back refs. Actually the full back refs is generic, and can be
828 * used in all cases the implicit back refs is used. The major shortcoming
829 * of the full back refs is its overhead. Every time a tree block gets
830 * COWed, we have to update back refs entry for all pointers in it.
832 * For a newly allocated tree block, we use implicit back refs for
833 * pointers in it. This means most tree related operations only involve
834 * implicit back refs. For a tree block created in old transaction, the
835 * only way to drop a reference to it is COW it. So we can detect the
836 * event that tree block loses its owner tree's reference and do the
837 * back refs conversion.
839 * When a tree block is COW'd through a tree, there are four cases:
841 * The reference count of the block is one and the tree is the block's
842 * owner tree. Nothing to do in this case.
844 * The reference count of the block is one and the tree is not the
845 * block's owner tree. In this case, full back refs is used for pointers
846 * in the block. Remove these full back refs, add implicit back refs for
847 * every pointers in the new block.
849 * The reference count of the block is greater than one and the tree is
850 * the block's owner tree. In this case, implicit back refs is used for
851 * pointers in the block. Add full back refs for every pointers in the
852 * block, increase lower level extents' reference counts. The original
853 * implicit back refs are entailed to the new block.
855 * The reference count of the block is greater than one and the tree is
856 * not the block's owner tree. Add implicit back refs for every pointer in
857 * the new block, increase lower level extents' reference count.
859 * Back Reference Key composing:
861 * The key objectid corresponds to the first byte in the extent,
862 * The key type is used to differentiate between types of back refs.
863 * There are different meanings of the key offset for different types
866 * File extents can be referenced by:
868 * - multiple snapshots, subvolumes, or different generations in one subvol
869 * - different files inside a single subvolume
870 * - different offsets inside a file (bookend extents in file.c)
872 * The extent ref structure for the implicit back refs has fields for:
874 * - Objectid of the subvolume root
875 * - objectid of the file holding the reference
876 * - original offset in the file
877 * - how many bookend extents
879 * The key offset for the implicit back refs is hash of the first
882 * The extent ref structure for the full back refs has field for:
884 * - number of pointers in the tree leaf
886 * The key offset for the implicit back refs is the first byte of
889 * When a file extent is allocated, The implicit back refs is used.
890 * the fields are filled in:
892 * (root_key.objectid, inode objectid, offset in file, 1)
894 * When a file extent is removed file truncation, we find the
895 * corresponding implicit back refs and check the following fields:
897 * (btrfs_header_owner(leaf), inode objectid, offset in file)
899 * Btree extents can be referenced by:
901 * - Different subvolumes
903 * Both the implicit back refs and the full back refs for tree blocks
904 * only consist of key. The key offset for the implicit back refs is
905 * objectid of block's owner tree. The key offset for the full back refs
906 * is the first byte of parent block.
908 * When implicit back refs is used, information about the lowest key and
909 * level of the tree block are required. These information are stored in
910 * tree block info structure.
913 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
914 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
915 struct btrfs_root *root,
916 struct btrfs_path *path,
917 u64 owner, u32 extra_size)
919 struct btrfs_extent_item *item;
920 struct btrfs_extent_item_v0 *ei0;
921 struct btrfs_extent_ref_v0 *ref0;
922 struct btrfs_tree_block_info *bi;
923 struct extent_buffer *leaf;
924 struct btrfs_key key;
925 struct btrfs_key found_key;
926 u32 new_size = sizeof(*item);
930 leaf = path->nodes[0];
931 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
933 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
934 ei0 = btrfs_item_ptr(leaf, path->slots[0],
935 struct btrfs_extent_item_v0);
936 refs = btrfs_extent_refs_v0(leaf, ei0);
938 if (owner == (u64)-1) {
940 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
941 ret = btrfs_next_leaf(root, path);
945 leaf = path->nodes[0];
947 btrfs_item_key_to_cpu(leaf, &found_key,
949 BUG_ON(key.objectid != found_key.objectid);
950 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
954 ref0 = btrfs_item_ptr(leaf, path->slots[0],
955 struct btrfs_extent_ref_v0);
956 owner = btrfs_ref_objectid_v0(leaf, ref0);
960 btrfs_release_path(path);
962 if (owner < BTRFS_FIRST_FREE_OBJECTID)
963 new_size += sizeof(*bi);
965 new_size -= sizeof(*ei0);
966 ret = btrfs_search_slot(trans, root, &key, path,
967 new_size + extra_size, 1);
972 ret = btrfs_extend_item(trans, root, path, new_size);
974 leaf = path->nodes[0];
975 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
976 btrfs_set_extent_refs(leaf, item, refs);
977 /* FIXME: get real generation */
978 btrfs_set_extent_generation(leaf, item, 0);
979 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
980 btrfs_set_extent_flags(leaf, item,
981 BTRFS_EXTENT_FLAG_TREE_BLOCK |
982 BTRFS_BLOCK_FLAG_FULL_BACKREF);
983 bi = (struct btrfs_tree_block_info *)(item + 1);
984 /* FIXME: get first key of the block */
985 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
986 btrfs_set_tree_block_level(leaf, bi, (int)owner);
988 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
990 btrfs_mark_buffer_dirty(leaf);
995 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
997 u32 high_crc = ~(u32)0;
998 u32 low_crc = ~(u32)0;
1001 lenum = cpu_to_le64(root_objectid);
1002 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
1003 lenum = cpu_to_le64(owner);
1004 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1005 lenum = cpu_to_le64(offset);
1006 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1008 return ((u64)high_crc << 31) ^ (u64)low_crc;
1011 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1012 struct btrfs_extent_data_ref *ref)
1014 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1015 btrfs_extent_data_ref_objectid(leaf, ref),
1016 btrfs_extent_data_ref_offset(leaf, ref));
1019 static int match_extent_data_ref(struct extent_buffer *leaf,
1020 struct btrfs_extent_data_ref *ref,
1021 u64 root_objectid, u64 owner, u64 offset)
1023 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1024 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1025 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1030 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1031 struct btrfs_root *root,
1032 struct btrfs_path *path,
1033 u64 bytenr, u64 parent,
1035 u64 owner, u64 offset)
1037 struct btrfs_key key;
1038 struct btrfs_extent_data_ref *ref;
1039 struct extent_buffer *leaf;
1045 key.objectid = bytenr;
1047 key.type = BTRFS_SHARED_DATA_REF_KEY;
1048 key.offset = parent;
1050 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1051 key.offset = hash_extent_data_ref(root_objectid,
1056 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1065 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1066 key.type = BTRFS_EXTENT_REF_V0_KEY;
1067 btrfs_release_path(path);
1068 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1079 leaf = path->nodes[0];
1080 nritems = btrfs_header_nritems(leaf);
1082 if (path->slots[0] >= nritems) {
1083 ret = btrfs_next_leaf(root, path);
1089 leaf = path->nodes[0];
1090 nritems = btrfs_header_nritems(leaf);
1094 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1095 if (key.objectid != bytenr ||
1096 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1099 ref = btrfs_item_ptr(leaf, path->slots[0],
1100 struct btrfs_extent_data_ref);
1102 if (match_extent_data_ref(leaf, ref, root_objectid,
1105 btrfs_release_path(path);
1117 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1118 struct btrfs_root *root,
1119 struct btrfs_path *path,
1120 u64 bytenr, u64 parent,
1121 u64 root_objectid, u64 owner,
1122 u64 offset, int refs_to_add)
1124 struct btrfs_key key;
1125 struct extent_buffer *leaf;
1130 key.objectid = bytenr;
1132 key.type = BTRFS_SHARED_DATA_REF_KEY;
1133 key.offset = parent;
1134 size = sizeof(struct btrfs_shared_data_ref);
1136 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1137 key.offset = hash_extent_data_ref(root_objectid,
1139 size = sizeof(struct btrfs_extent_data_ref);
1142 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1143 if (ret && ret != -EEXIST)
1146 leaf = path->nodes[0];
1148 struct btrfs_shared_data_ref *ref;
1149 ref = btrfs_item_ptr(leaf, path->slots[0],
1150 struct btrfs_shared_data_ref);
1152 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1154 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1155 num_refs += refs_to_add;
1156 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1159 struct btrfs_extent_data_ref *ref;
1160 while (ret == -EEXIST) {
1161 ref = btrfs_item_ptr(leaf, path->slots[0],
1162 struct btrfs_extent_data_ref);
1163 if (match_extent_data_ref(leaf, ref, root_objectid,
1166 btrfs_release_path(path);
1168 ret = btrfs_insert_empty_item(trans, root, path, &key,
1170 if (ret && ret != -EEXIST)
1173 leaf = path->nodes[0];
1175 ref = btrfs_item_ptr(leaf, path->slots[0],
1176 struct btrfs_extent_data_ref);
1178 btrfs_set_extent_data_ref_root(leaf, ref,
1180 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1181 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1182 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1184 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1185 num_refs += refs_to_add;
1186 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1189 btrfs_mark_buffer_dirty(leaf);
1192 btrfs_release_path(path);
1196 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1197 struct btrfs_root *root,
1198 struct btrfs_path *path,
1201 struct btrfs_key key;
1202 struct btrfs_extent_data_ref *ref1 = NULL;
1203 struct btrfs_shared_data_ref *ref2 = NULL;
1204 struct extent_buffer *leaf;
1208 leaf = path->nodes[0];
1209 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1211 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1212 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1213 struct btrfs_extent_data_ref);
1214 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1215 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1216 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1217 struct btrfs_shared_data_ref);
1218 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1219 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1220 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1221 struct btrfs_extent_ref_v0 *ref0;
1222 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1223 struct btrfs_extent_ref_v0);
1224 num_refs = btrfs_ref_count_v0(leaf, ref0);
1230 BUG_ON(num_refs < refs_to_drop);
1231 num_refs -= refs_to_drop;
1233 if (num_refs == 0) {
1234 ret = btrfs_del_item(trans, root, path);
1236 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1237 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1238 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1239 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1240 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1242 struct btrfs_extent_ref_v0 *ref0;
1243 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1244 struct btrfs_extent_ref_v0);
1245 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1248 btrfs_mark_buffer_dirty(leaf);
1253 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1254 struct btrfs_path *path,
1255 struct btrfs_extent_inline_ref *iref)
1257 struct btrfs_key key;
1258 struct extent_buffer *leaf;
1259 struct btrfs_extent_data_ref *ref1;
1260 struct btrfs_shared_data_ref *ref2;
1263 leaf = path->nodes[0];
1264 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1266 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1267 BTRFS_EXTENT_DATA_REF_KEY) {
1268 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1269 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1271 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1272 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1274 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1275 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1276 struct btrfs_extent_data_ref);
1277 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1278 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1279 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1280 struct btrfs_shared_data_ref);
1281 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1282 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1283 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1284 struct btrfs_extent_ref_v0 *ref0;
1285 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1286 struct btrfs_extent_ref_v0);
1287 num_refs = btrfs_ref_count_v0(leaf, ref0);
1295 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1296 struct btrfs_root *root,
1297 struct btrfs_path *path,
1298 u64 bytenr, u64 parent,
1301 struct btrfs_key key;
1304 key.objectid = bytenr;
1306 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1307 key.offset = parent;
1309 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1310 key.offset = root_objectid;
1313 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1316 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1317 if (ret == -ENOENT && parent) {
1318 btrfs_release_path(path);
1319 key.type = BTRFS_EXTENT_REF_V0_KEY;
1320 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1328 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1329 struct btrfs_root *root,
1330 struct btrfs_path *path,
1331 u64 bytenr, u64 parent,
1334 struct btrfs_key key;
1337 key.objectid = bytenr;
1339 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1340 key.offset = parent;
1342 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1343 key.offset = root_objectid;
1346 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1347 btrfs_release_path(path);
1351 static inline int extent_ref_type(u64 parent, u64 owner)
1354 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1356 type = BTRFS_SHARED_BLOCK_REF_KEY;
1358 type = BTRFS_TREE_BLOCK_REF_KEY;
1361 type = BTRFS_SHARED_DATA_REF_KEY;
1363 type = BTRFS_EXTENT_DATA_REF_KEY;
1368 static int find_next_key(struct btrfs_path *path, int level,
1369 struct btrfs_key *key)
1372 for (; level < BTRFS_MAX_LEVEL; level++) {
1373 if (!path->nodes[level])
1375 if (path->slots[level] + 1 >=
1376 btrfs_header_nritems(path->nodes[level]))
1379 btrfs_item_key_to_cpu(path->nodes[level], key,
1380 path->slots[level] + 1);
1382 btrfs_node_key_to_cpu(path->nodes[level], key,
1383 path->slots[level] + 1);
1390 * look for inline back ref. if back ref is found, *ref_ret is set
1391 * to the address of inline back ref, and 0 is returned.
1393 * if back ref isn't found, *ref_ret is set to the address where it
1394 * should be inserted, and -ENOENT is returned.
1396 * if insert is true and there are too many inline back refs, the path
1397 * points to the extent item, and -EAGAIN is returned.
1399 * NOTE: inline back refs are ordered in the same way that back ref
1400 * items in the tree are ordered.
1402 static noinline_for_stack
1403 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1404 struct btrfs_root *root,
1405 struct btrfs_path *path,
1406 struct btrfs_extent_inline_ref **ref_ret,
1407 u64 bytenr, u64 num_bytes,
1408 u64 parent, u64 root_objectid,
1409 u64 owner, u64 offset, int insert)
1411 struct btrfs_key key;
1412 struct extent_buffer *leaf;
1413 struct btrfs_extent_item *ei;
1414 struct btrfs_extent_inline_ref *iref;
1425 key.objectid = bytenr;
1426 key.type = BTRFS_EXTENT_ITEM_KEY;
1427 key.offset = num_bytes;
1429 want = extent_ref_type(parent, owner);
1431 extra_size = btrfs_extent_inline_ref_size(want);
1432 path->keep_locks = 1;
1435 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1442 leaf = path->nodes[0];
1443 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1444 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1445 if (item_size < sizeof(*ei)) {
1450 ret = convert_extent_item_v0(trans, root, path, owner,
1456 leaf = path->nodes[0];
1457 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1460 BUG_ON(item_size < sizeof(*ei));
1462 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1463 flags = btrfs_extent_flags(leaf, ei);
1465 ptr = (unsigned long)(ei + 1);
1466 end = (unsigned long)ei + item_size;
1468 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1469 ptr += sizeof(struct btrfs_tree_block_info);
1472 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1481 iref = (struct btrfs_extent_inline_ref *)ptr;
1482 type = btrfs_extent_inline_ref_type(leaf, iref);
1486 ptr += btrfs_extent_inline_ref_size(type);
1490 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1491 struct btrfs_extent_data_ref *dref;
1492 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1493 if (match_extent_data_ref(leaf, dref, root_objectid,
1498 if (hash_extent_data_ref_item(leaf, dref) <
1499 hash_extent_data_ref(root_objectid, owner, offset))
1503 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1505 if (parent == ref_offset) {
1509 if (ref_offset < parent)
1512 if (root_objectid == ref_offset) {
1516 if (ref_offset < root_objectid)
1520 ptr += btrfs_extent_inline_ref_size(type);
1522 if (err == -ENOENT && insert) {
1523 if (item_size + extra_size >=
1524 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1529 * To add new inline back ref, we have to make sure
1530 * there is no corresponding back ref item.
1531 * For simplicity, we just do not add new inline back
1532 * ref if there is any kind of item for this block
1534 if (find_next_key(path, 0, &key) == 0 &&
1535 key.objectid == bytenr &&
1536 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1541 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1544 path->keep_locks = 0;
1545 btrfs_unlock_up_safe(path, 1);
1551 * helper to add new inline back ref
1553 static noinline_for_stack
1554 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1555 struct btrfs_root *root,
1556 struct btrfs_path *path,
1557 struct btrfs_extent_inline_ref *iref,
1558 u64 parent, u64 root_objectid,
1559 u64 owner, u64 offset, int refs_to_add,
1560 struct btrfs_delayed_extent_op *extent_op)
1562 struct extent_buffer *leaf;
1563 struct btrfs_extent_item *ei;
1566 unsigned long item_offset;
1572 leaf = path->nodes[0];
1573 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1574 item_offset = (unsigned long)iref - (unsigned long)ei;
1576 type = extent_ref_type(parent, owner);
1577 size = btrfs_extent_inline_ref_size(type);
1579 ret = btrfs_extend_item(trans, root, path, size);
1581 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1582 refs = btrfs_extent_refs(leaf, ei);
1583 refs += refs_to_add;
1584 btrfs_set_extent_refs(leaf, ei, refs);
1586 __run_delayed_extent_op(extent_op, leaf, ei);
1588 ptr = (unsigned long)ei + item_offset;
1589 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1590 if (ptr < end - size)
1591 memmove_extent_buffer(leaf, ptr + size, ptr,
1594 iref = (struct btrfs_extent_inline_ref *)ptr;
1595 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1596 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1597 struct btrfs_extent_data_ref *dref;
1598 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1599 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1600 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1601 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1602 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1603 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1604 struct btrfs_shared_data_ref *sref;
1605 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1606 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1607 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1608 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1609 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1611 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1613 btrfs_mark_buffer_dirty(leaf);
1617 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1618 struct btrfs_root *root,
1619 struct btrfs_path *path,
1620 struct btrfs_extent_inline_ref **ref_ret,
1621 u64 bytenr, u64 num_bytes, u64 parent,
1622 u64 root_objectid, u64 owner, u64 offset)
1626 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1627 bytenr, num_bytes, parent,
1628 root_objectid, owner, offset, 0);
1632 btrfs_release_path(path);
1635 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1636 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1639 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1640 root_objectid, owner, offset);
1646 * helper to update/remove inline back ref
1648 static noinline_for_stack
1649 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1650 struct btrfs_root *root,
1651 struct btrfs_path *path,
1652 struct btrfs_extent_inline_ref *iref,
1654 struct btrfs_delayed_extent_op *extent_op)
1656 struct extent_buffer *leaf;
1657 struct btrfs_extent_item *ei;
1658 struct btrfs_extent_data_ref *dref = NULL;
1659 struct btrfs_shared_data_ref *sref = NULL;
1668 leaf = path->nodes[0];
1669 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1670 refs = btrfs_extent_refs(leaf, ei);
1671 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1672 refs += refs_to_mod;
1673 btrfs_set_extent_refs(leaf, ei, refs);
1675 __run_delayed_extent_op(extent_op, leaf, ei);
1677 type = btrfs_extent_inline_ref_type(leaf, iref);
1679 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1680 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1681 refs = btrfs_extent_data_ref_count(leaf, dref);
1682 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1683 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1684 refs = btrfs_shared_data_ref_count(leaf, sref);
1687 BUG_ON(refs_to_mod != -1);
1690 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1691 refs += refs_to_mod;
1694 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1695 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1697 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1699 size = btrfs_extent_inline_ref_size(type);
1700 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1701 ptr = (unsigned long)iref;
1702 end = (unsigned long)ei + item_size;
1703 if (ptr + size < end)
1704 memmove_extent_buffer(leaf, ptr, ptr + size,
1707 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1709 btrfs_mark_buffer_dirty(leaf);
1713 static noinline_for_stack
1714 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1715 struct btrfs_root *root,
1716 struct btrfs_path *path,
1717 u64 bytenr, u64 num_bytes, u64 parent,
1718 u64 root_objectid, u64 owner,
1719 u64 offset, int refs_to_add,
1720 struct btrfs_delayed_extent_op *extent_op)
1722 struct btrfs_extent_inline_ref *iref;
1725 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1726 bytenr, num_bytes, parent,
1727 root_objectid, owner, offset, 1);
1729 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1730 ret = update_inline_extent_backref(trans, root, path, iref,
1731 refs_to_add, extent_op);
1732 } else if (ret == -ENOENT) {
1733 ret = setup_inline_extent_backref(trans, root, path, iref,
1734 parent, root_objectid,
1735 owner, offset, refs_to_add,
1741 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1742 struct btrfs_root *root,
1743 struct btrfs_path *path,
1744 u64 bytenr, u64 parent, u64 root_objectid,
1745 u64 owner, u64 offset, int refs_to_add)
1748 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1749 BUG_ON(refs_to_add != 1);
1750 ret = insert_tree_block_ref(trans, root, path, bytenr,
1751 parent, root_objectid);
1753 ret = insert_extent_data_ref(trans, root, path, bytenr,
1754 parent, root_objectid,
1755 owner, offset, refs_to_add);
1760 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1761 struct btrfs_root *root,
1762 struct btrfs_path *path,
1763 struct btrfs_extent_inline_ref *iref,
1764 int refs_to_drop, int is_data)
1768 BUG_ON(!is_data && refs_to_drop != 1);
1770 ret = update_inline_extent_backref(trans, root, path, iref,
1771 -refs_to_drop, NULL);
1772 } else if (is_data) {
1773 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1775 ret = btrfs_del_item(trans, root, path);
1780 static int btrfs_issue_discard(struct block_device *bdev,
1783 return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0);
1786 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1787 u64 num_bytes, u64 *actual_bytes)
1790 u64 discarded_bytes = 0;
1791 struct btrfs_multi_bio *multi = NULL;
1794 /* Tell the block device(s) that the sectors can be discarded */
1795 ret = btrfs_map_block(&root->fs_info->mapping_tree, REQ_DISCARD,
1796 bytenr, &num_bytes, &multi, 0);
1798 struct btrfs_bio_stripe *stripe = multi->stripes;
1802 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1803 if (!stripe->dev->can_discard)
1806 ret = btrfs_issue_discard(stripe->dev->bdev,
1810 discarded_bytes += stripe->length;
1811 else if (ret != -EOPNOTSUPP)
1815 * Just in case we get back EOPNOTSUPP for some reason,
1816 * just ignore the return value so we don't screw up
1817 * people calling discard_extent.
1825 *actual_bytes = discarded_bytes;
1831 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1832 struct btrfs_root *root,
1833 u64 bytenr, u64 num_bytes, u64 parent,
1834 u64 root_objectid, u64 owner, u64 offset)
1837 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1838 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1840 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1841 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1842 parent, root_objectid, (int)owner,
1843 BTRFS_ADD_DELAYED_REF, NULL);
1845 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1846 parent, root_objectid, owner, offset,
1847 BTRFS_ADD_DELAYED_REF, NULL);
1852 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1853 struct btrfs_root *root,
1854 u64 bytenr, u64 num_bytes,
1855 u64 parent, u64 root_objectid,
1856 u64 owner, u64 offset, int refs_to_add,
1857 struct btrfs_delayed_extent_op *extent_op)
1859 struct btrfs_path *path;
1860 struct extent_buffer *leaf;
1861 struct btrfs_extent_item *item;
1866 path = btrfs_alloc_path();
1871 path->leave_spinning = 1;
1872 /* this will setup the path even if it fails to insert the back ref */
1873 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1874 path, bytenr, num_bytes, parent,
1875 root_objectid, owner, offset,
1876 refs_to_add, extent_op);
1880 if (ret != -EAGAIN) {
1885 leaf = path->nodes[0];
1886 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1887 refs = btrfs_extent_refs(leaf, item);
1888 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1890 __run_delayed_extent_op(extent_op, leaf, item);
1892 btrfs_mark_buffer_dirty(leaf);
1893 btrfs_release_path(path);
1896 path->leave_spinning = 1;
1898 /* now insert the actual backref */
1899 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1900 path, bytenr, parent, root_objectid,
1901 owner, offset, refs_to_add);
1904 btrfs_free_path(path);
1908 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1909 struct btrfs_root *root,
1910 struct btrfs_delayed_ref_node *node,
1911 struct btrfs_delayed_extent_op *extent_op,
1912 int insert_reserved)
1915 struct btrfs_delayed_data_ref *ref;
1916 struct btrfs_key ins;
1921 ins.objectid = node->bytenr;
1922 ins.offset = node->num_bytes;
1923 ins.type = BTRFS_EXTENT_ITEM_KEY;
1925 ref = btrfs_delayed_node_to_data_ref(node);
1926 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1927 parent = ref->parent;
1929 ref_root = ref->root;
1931 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1933 BUG_ON(extent_op->update_key);
1934 flags |= extent_op->flags_to_set;
1936 ret = alloc_reserved_file_extent(trans, root,
1937 parent, ref_root, flags,
1938 ref->objectid, ref->offset,
1939 &ins, node->ref_mod);
1940 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1941 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1942 node->num_bytes, parent,
1943 ref_root, ref->objectid,
1944 ref->offset, node->ref_mod,
1946 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1947 ret = __btrfs_free_extent(trans, root, node->bytenr,
1948 node->num_bytes, parent,
1949 ref_root, ref->objectid,
1950 ref->offset, node->ref_mod,
1958 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1959 struct extent_buffer *leaf,
1960 struct btrfs_extent_item *ei)
1962 u64 flags = btrfs_extent_flags(leaf, ei);
1963 if (extent_op->update_flags) {
1964 flags |= extent_op->flags_to_set;
1965 btrfs_set_extent_flags(leaf, ei, flags);
1968 if (extent_op->update_key) {
1969 struct btrfs_tree_block_info *bi;
1970 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1971 bi = (struct btrfs_tree_block_info *)(ei + 1);
1972 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1976 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1977 struct btrfs_root *root,
1978 struct btrfs_delayed_ref_node *node,
1979 struct btrfs_delayed_extent_op *extent_op)
1981 struct btrfs_key key;
1982 struct btrfs_path *path;
1983 struct btrfs_extent_item *ei;
1984 struct extent_buffer *leaf;
1989 path = btrfs_alloc_path();
1993 key.objectid = node->bytenr;
1994 key.type = BTRFS_EXTENT_ITEM_KEY;
1995 key.offset = node->num_bytes;
1998 path->leave_spinning = 1;
1999 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
2010 leaf = path->nodes[0];
2011 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2012 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2013 if (item_size < sizeof(*ei)) {
2014 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
2020 leaf = path->nodes[0];
2021 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2024 BUG_ON(item_size < sizeof(*ei));
2025 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2026 __run_delayed_extent_op(extent_op, leaf, ei);
2028 btrfs_mark_buffer_dirty(leaf);
2030 btrfs_free_path(path);
2034 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2035 struct btrfs_root *root,
2036 struct btrfs_delayed_ref_node *node,
2037 struct btrfs_delayed_extent_op *extent_op,
2038 int insert_reserved)
2041 struct btrfs_delayed_tree_ref *ref;
2042 struct btrfs_key ins;
2046 ins.objectid = node->bytenr;
2047 ins.offset = node->num_bytes;
2048 ins.type = BTRFS_EXTENT_ITEM_KEY;
2050 ref = btrfs_delayed_node_to_tree_ref(node);
2051 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2052 parent = ref->parent;
2054 ref_root = ref->root;
2056 BUG_ON(node->ref_mod != 1);
2057 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2058 BUG_ON(!extent_op || !extent_op->update_flags ||
2059 !extent_op->update_key);
2060 ret = alloc_reserved_tree_block(trans, root,
2062 extent_op->flags_to_set,
2065 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2066 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2067 node->num_bytes, parent, ref_root,
2068 ref->level, 0, 1, extent_op);
2069 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2070 ret = __btrfs_free_extent(trans, root, node->bytenr,
2071 node->num_bytes, parent, ref_root,
2072 ref->level, 0, 1, extent_op);
2079 /* helper function to actually process a single delayed ref entry */
2080 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2081 struct btrfs_root *root,
2082 struct btrfs_delayed_ref_node *node,
2083 struct btrfs_delayed_extent_op *extent_op,
2084 int insert_reserved)
2087 if (btrfs_delayed_ref_is_head(node)) {
2088 struct btrfs_delayed_ref_head *head;
2090 * we've hit the end of the chain and we were supposed
2091 * to insert this extent into the tree. But, it got
2092 * deleted before we ever needed to insert it, so all
2093 * we have to do is clean up the accounting
2096 head = btrfs_delayed_node_to_head(node);
2097 if (insert_reserved) {
2098 btrfs_pin_extent(root, node->bytenr,
2099 node->num_bytes, 1);
2100 if (head->is_data) {
2101 ret = btrfs_del_csums(trans, root,
2107 mutex_unlock(&head->mutex);
2111 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2112 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2113 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2115 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2116 node->type == BTRFS_SHARED_DATA_REF_KEY)
2117 ret = run_delayed_data_ref(trans, root, node, extent_op,
2124 static noinline struct btrfs_delayed_ref_node *
2125 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2127 struct rb_node *node;
2128 struct btrfs_delayed_ref_node *ref;
2129 int action = BTRFS_ADD_DELAYED_REF;
2132 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2133 * this prevents ref count from going down to zero when
2134 * there still are pending delayed ref.
2136 node = rb_prev(&head->node.rb_node);
2140 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2142 if (ref->bytenr != head->node.bytenr)
2144 if (ref->action == action)
2146 node = rb_prev(node);
2148 if (action == BTRFS_ADD_DELAYED_REF) {
2149 action = BTRFS_DROP_DELAYED_REF;
2155 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2156 struct btrfs_root *root,
2157 struct list_head *cluster)
2159 struct btrfs_delayed_ref_root *delayed_refs;
2160 struct btrfs_delayed_ref_node *ref;
2161 struct btrfs_delayed_ref_head *locked_ref = NULL;
2162 struct btrfs_delayed_extent_op *extent_op;
2165 int must_insert_reserved = 0;
2167 delayed_refs = &trans->transaction->delayed_refs;
2170 /* pick a new head ref from the cluster list */
2171 if (list_empty(cluster))
2174 locked_ref = list_entry(cluster->next,
2175 struct btrfs_delayed_ref_head, cluster);
2177 /* grab the lock that says we are going to process
2178 * all the refs for this head */
2179 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2182 * we may have dropped the spin lock to get the head
2183 * mutex lock, and that might have given someone else
2184 * time to free the head. If that's true, it has been
2185 * removed from our list and we can move on.
2187 if (ret == -EAGAIN) {
2195 * record the must insert reserved flag before we
2196 * drop the spin lock.
2198 must_insert_reserved = locked_ref->must_insert_reserved;
2199 locked_ref->must_insert_reserved = 0;
2201 extent_op = locked_ref->extent_op;
2202 locked_ref->extent_op = NULL;
2205 * locked_ref is the head node, so we have to go one
2206 * node back for any delayed ref updates
2208 ref = select_delayed_ref(locked_ref);
2210 /* All delayed refs have been processed, Go ahead
2211 * and send the head node to run_one_delayed_ref,
2212 * so that any accounting fixes can happen
2214 ref = &locked_ref->node;
2216 if (extent_op && must_insert_reserved) {
2222 spin_unlock(&delayed_refs->lock);
2224 ret = run_delayed_extent_op(trans, root,
2230 spin_lock(&delayed_refs->lock);
2234 list_del_init(&locked_ref->cluster);
2239 rb_erase(&ref->rb_node, &delayed_refs->root);
2240 delayed_refs->num_entries--;
2242 spin_unlock(&delayed_refs->lock);
2244 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2245 must_insert_reserved);
2248 btrfs_put_delayed_ref(ref);
2253 spin_lock(&delayed_refs->lock);
2259 * this starts processing the delayed reference count updates and
2260 * extent insertions we have queued up so far. count can be
2261 * 0, which means to process everything in the tree at the start
2262 * of the run (but not newly added entries), or it can be some target
2263 * number you'd like to process.
2265 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2266 struct btrfs_root *root, unsigned long count)
2268 struct rb_node *node;
2269 struct btrfs_delayed_ref_root *delayed_refs;
2270 struct btrfs_delayed_ref_node *ref;
2271 struct list_head cluster;
2273 int run_all = count == (unsigned long)-1;
2276 if (root == root->fs_info->extent_root)
2277 root = root->fs_info->tree_root;
2279 delayed_refs = &trans->transaction->delayed_refs;
2280 INIT_LIST_HEAD(&cluster);
2282 spin_lock(&delayed_refs->lock);
2284 count = delayed_refs->num_entries * 2;
2288 if (!(run_all || run_most) &&
2289 delayed_refs->num_heads_ready < 64)
2293 * go find something we can process in the rbtree. We start at
2294 * the beginning of the tree, and then build a cluster
2295 * of refs to process starting at the first one we are able to
2298 ret = btrfs_find_ref_cluster(trans, &cluster,
2299 delayed_refs->run_delayed_start);
2303 ret = run_clustered_refs(trans, root, &cluster);
2306 count -= min_t(unsigned long, ret, count);
2313 node = rb_first(&delayed_refs->root);
2316 count = (unsigned long)-1;
2319 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2321 if (btrfs_delayed_ref_is_head(ref)) {
2322 struct btrfs_delayed_ref_head *head;
2324 head = btrfs_delayed_node_to_head(ref);
2325 atomic_inc(&ref->refs);
2327 spin_unlock(&delayed_refs->lock);
2329 * Mutex was contended, block until it's
2330 * released and try again
2332 mutex_lock(&head->mutex);
2333 mutex_unlock(&head->mutex);
2335 btrfs_put_delayed_ref(ref);
2339 node = rb_next(node);
2341 spin_unlock(&delayed_refs->lock);
2342 schedule_timeout(1);
2346 spin_unlock(&delayed_refs->lock);
2350 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2351 struct btrfs_root *root,
2352 u64 bytenr, u64 num_bytes, u64 flags,
2355 struct btrfs_delayed_extent_op *extent_op;
2358 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2362 extent_op->flags_to_set = flags;
2363 extent_op->update_flags = 1;
2364 extent_op->update_key = 0;
2365 extent_op->is_data = is_data ? 1 : 0;
2367 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2373 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2374 struct btrfs_root *root,
2375 struct btrfs_path *path,
2376 u64 objectid, u64 offset, u64 bytenr)
2378 struct btrfs_delayed_ref_head *head;
2379 struct btrfs_delayed_ref_node *ref;
2380 struct btrfs_delayed_data_ref *data_ref;
2381 struct btrfs_delayed_ref_root *delayed_refs;
2382 struct rb_node *node;
2386 delayed_refs = &trans->transaction->delayed_refs;
2387 spin_lock(&delayed_refs->lock);
2388 head = btrfs_find_delayed_ref_head(trans, bytenr);
2392 if (!mutex_trylock(&head->mutex)) {
2393 atomic_inc(&head->node.refs);
2394 spin_unlock(&delayed_refs->lock);
2396 btrfs_release_path(path);
2399 * Mutex was contended, block until it's released and let
2402 mutex_lock(&head->mutex);
2403 mutex_unlock(&head->mutex);
2404 btrfs_put_delayed_ref(&head->node);
2408 node = rb_prev(&head->node.rb_node);
2412 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2414 if (ref->bytenr != bytenr)
2418 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2421 data_ref = btrfs_delayed_node_to_data_ref(ref);
2423 node = rb_prev(node);
2425 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2426 if (ref->bytenr == bytenr)
2430 if (data_ref->root != root->root_key.objectid ||
2431 data_ref->objectid != objectid || data_ref->offset != offset)
2436 mutex_unlock(&head->mutex);
2438 spin_unlock(&delayed_refs->lock);
2442 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2443 struct btrfs_root *root,
2444 struct btrfs_path *path,
2445 u64 objectid, u64 offset, u64 bytenr)
2447 struct btrfs_root *extent_root = root->fs_info->extent_root;
2448 struct extent_buffer *leaf;
2449 struct btrfs_extent_data_ref *ref;
2450 struct btrfs_extent_inline_ref *iref;
2451 struct btrfs_extent_item *ei;
2452 struct btrfs_key key;
2456 key.objectid = bytenr;
2457 key.offset = (u64)-1;
2458 key.type = BTRFS_EXTENT_ITEM_KEY;
2460 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2466 if (path->slots[0] == 0)
2470 leaf = path->nodes[0];
2471 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2473 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2477 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2478 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2479 if (item_size < sizeof(*ei)) {
2480 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2484 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2486 if (item_size != sizeof(*ei) +
2487 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2490 if (btrfs_extent_generation(leaf, ei) <=
2491 btrfs_root_last_snapshot(&root->root_item))
2494 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2495 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2496 BTRFS_EXTENT_DATA_REF_KEY)
2499 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2500 if (btrfs_extent_refs(leaf, ei) !=
2501 btrfs_extent_data_ref_count(leaf, ref) ||
2502 btrfs_extent_data_ref_root(leaf, ref) !=
2503 root->root_key.objectid ||
2504 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2505 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2513 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2514 struct btrfs_root *root,
2515 u64 objectid, u64 offset, u64 bytenr)
2517 struct btrfs_path *path;
2521 path = btrfs_alloc_path();
2526 ret = check_committed_ref(trans, root, path, objectid,
2528 if (ret && ret != -ENOENT)
2531 ret2 = check_delayed_ref(trans, root, path, objectid,
2533 } while (ret2 == -EAGAIN);
2535 if (ret2 && ret2 != -ENOENT) {
2540 if (ret != -ENOENT || ret2 != -ENOENT)
2543 btrfs_free_path(path);
2544 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2549 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2550 struct btrfs_root *root,
2551 struct extent_buffer *buf,
2552 int full_backref, int inc)
2559 struct btrfs_key key;
2560 struct btrfs_file_extent_item *fi;
2564 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2565 u64, u64, u64, u64, u64, u64);
2567 ref_root = btrfs_header_owner(buf);
2568 nritems = btrfs_header_nritems(buf);
2569 level = btrfs_header_level(buf);
2571 if (!root->ref_cows && level == 0)
2575 process_func = btrfs_inc_extent_ref;
2577 process_func = btrfs_free_extent;
2580 parent = buf->start;
2584 for (i = 0; i < nritems; i++) {
2586 btrfs_item_key_to_cpu(buf, &key, i);
2587 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2589 fi = btrfs_item_ptr(buf, i,
2590 struct btrfs_file_extent_item);
2591 if (btrfs_file_extent_type(buf, fi) ==
2592 BTRFS_FILE_EXTENT_INLINE)
2594 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2598 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2599 key.offset -= btrfs_file_extent_offset(buf, fi);
2600 ret = process_func(trans, root, bytenr, num_bytes,
2601 parent, ref_root, key.objectid,
2606 bytenr = btrfs_node_blockptr(buf, i);
2607 num_bytes = btrfs_level_size(root, level - 1);
2608 ret = process_func(trans, root, bytenr, num_bytes,
2609 parent, ref_root, level - 1, 0);
2620 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2621 struct extent_buffer *buf, int full_backref)
2623 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2626 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2627 struct extent_buffer *buf, int full_backref)
2629 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2632 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2633 struct btrfs_root *root,
2634 struct btrfs_path *path,
2635 struct btrfs_block_group_cache *cache)
2638 struct btrfs_root *extent_root = root->fs_info->extent_root;
2640 struct extent_buffer *leaf;
2642 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2647 leaf = path->nodes[0];
2648 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2649 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2650 btrfs_mark_buffer_dirty(leaf);
2651 btrfs_release_path(path);
2659 static struct btrfs_block_group_cache *
2660 next_block_group(struct btrfs_root *root,
2661 struct btrfs_block_group_cache *cache)
2663 struct rb_node *node;
2664 spin_lock(&root->fs_info->block_group_cache_lock);
2665 node = rb_next(&cache->cache_node);
2666 btrfs_put_block_group(cache);
2668 cache = rb_entry(node, struct btrfs_block_group_cache,
2670 btrfs_get_block_group(cache);
2673 spin_unlock(&root->fs_info->block_group_cache_lock);
2677 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2678 struct btrfs_trans_handle *trans,
2679 struct btrfs_path *path)
2681 struct btrfs_root *root = block_group->fs_info->tree_root;
2682 struct inode *inode = NULL;
2684 int dcs = BTRFS_DC_ERROR;
2690 * If this block group is smaller than 100 megs don't bother caching the
2693 if (block_group->key.offset < (100 * 1024 * 1024)) {
2694 spin_lock(&block_group->lock);
2695 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2696 spin_unlock(&block_group->lock);
2701 inode = lookup_free_space_inode(root, block_group, path);
2702 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2703 ret = PTR_ERR(inode);
2704 btrfs_release_path(path);
2708 if (IS_ERR(inode)) {
2712 if (block_group->ro)
2715 ret = create_free_space_inode(root, trans, block_group, path);
2721 /* We've already setup this transaction, go ahead and exit */
2722 if (block_group->cache_generation == trans->transid &&
2723 i_size_read(inode)) {
2724 dcs = BTRFS_DC_SETUP;
2729 * We want to set the generation to 0, that way if anything goes wrong
2730 * from here on out we know not to trust this cache when we load up next
2733 BTRFS_I(inode)->generation = 0;
2734 ret = btrfs_update_inode(trans, root, inode);
2737 if (i_size_read(inode) > 0) {
2738 ret = btrfs_truncate_free_space_cache(root, trans, path,
2744 spin_lock(&block_group->lock);
2745 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2746 /* We're not cached, don't bother trying to write stuff out */
2747 dcs = BTRFS_DC_WRITTEN;
2748 spin_unlock(&block_group->lock);
2751 spin_unlock(&block_group->lock);
2753 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2758 * Just to make absolutely sure we have enough space, we're going to
2759 * preallocate 12 pages worth of space for each block group. In
2760 * practice we ought to use at most 8, but we need extra space so we can
2761 * add our header and have a terminator between the extents and the
2765 num_pages *= PAGE_CACHE_SIZE;
2767 ret = btrfs_check_data_free_space(inode, num_pages);
2771 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2772 num_pages, num_pages,
2775 dcs = BTRFS_DC_SETUP;
2776 btrfs_free_reserved_data_space(inode, num_pages);
2781 btrfs_release_path(path);
2783 spin_lock(&block_group->lock);
2785 block_group->cache_generation = trans->transid;
2786 block_group->disk_cache_state = dcs;
2787 spin_unlock(&block_group->lock);
2792 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2793 struct btrfs_root *root)
2795 struct btrfs_block_group_cache *cache;
2797 struct btrfs_path *path;
2800 path = btrfs_alloc_path();
2806 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2808 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2810 cache = next_block_group(root, cache);
2818 err = cache_save_setup(cache, trans, path);
2819 last = cache->key.objectid + cache->key.offset;
2820 btrfs_put_block_group(cache);
2825 err = btrfs_run_delayed_refs(trans, root,
2830 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2832 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2833 btrfs_put_block_group(cache);
2839 cache = next_block_group(root, cache);
2848 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2849 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2851 last = cache->key.objectid + cache->key.offset;
2853 err = write_one_cache_group(trans, root, path, cache);
2855 btrfs_put_block_group(cache);
2860 * I don't think this is needed since we're just marking our
2861 * preallocated extent as written, but just in case it can't
2865 err = btrfs_run_delayed_refs(trans, root,
2870 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2873 * Really this shouldn't happen, but it could if we
2874 * couldn't write the entire preallocated extent and
2875 * splitting the extent resulted in a new block.
2878 btrfs_put_block_group(cache);
2881 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2883 cache = next_block_group(root, cache);
2892 btrfs_write_out_cache(root, trans, cache, path);
2895 * If we didn't have an error then the cache state is still
2896 * NEED_WRITE, so we can set it to WRITTEN.
2898 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2899 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2900 last = cache->key.objectid + cache->key.offset;
2901 btrfs_put_block_group(cache);
2904 btrfs_free_path(path);
2908 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2910 struct btrfs_block_group_cache *block_group;
2913 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2914 if (!block_group || block_group->ro)
2917 btrfs_put_block_group(block_group);
2921 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2922 u64 total_bytes, u64 bytes_used,
2923 struct btrfs_space_info **space_info)
2925 struct btrfs_space_info *found;
2929 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2930 BTRFS_BLOCK_GROUP_RAID10))
2935 found = __find_space_info(info, flags);
2937 spin_lock(&found->lock);
2938 found->total_bytes += total_bytes;
2939 found->disk_total += total_bytes * factor;
2940 found->bytes_used += bytes_used;
2941 found->disk_used += bytes_used * factor;
2943 spin_unlock(&found->lock);
2944 *space_info = found;
2947 found = kzalloc(sizeof(*found), GFP_NOFS);
2951 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
2952 INIT_LIST_HEAD(&found->block_groups[i]);
2953 init_rwsem(&found->groups_sem);
2954 spin_lock_init(&found->lock);
2955 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
2956 BTRFS_BLOCK_GROUP_SYSTEM |
2957 BTRFS_BLOCK_GROUP_METADATA);
2958 found->total_bytes = total_bytes;
2959 found->disk_total = total_bytes * factor;
2960 found->bytes_used = bytes_used;
2961 found->disk_used = bytes_used * factor;
2962 found->bytes_pinned = 0;
2963 found->bytes_reserved = 0;
2964 found->bytes_readonly = 0;
2965 found->bytes_may_use = 0;
2967 found->force_alloc = CHUNK_ALLOC_NO_FORCE;
2968 found->chunk_alloc = 0;
2970 init_waitqueue_head(&found->wait);
2971 *space_info = found;
2972 list_add_rcu(&found->list, &info->space_info);
2976 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
2978 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
2979 BTRFS_BLOCK_GROUP_RAID1 |
2980 BTRFS_BLOCK_GROUP_RAID10 |
2981 BTRFS_BLOCK_GROUP_DUP);
2983 if (flags & BTRFS_BLOCK_GROUP_DATA)
2984 fs_info->avail_data_alloc_bits |= extra_flags;
2985 if (flags & BTRFS_BLOCK_GROUP_METADATA)
2986 fs_info->avail_metadata_alloc_bits |= extra_flags;
2987 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
2988 fs_info->avail_system_alloc_bits |= extra_flags;
2992 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
2995 * we add in the count of missing devices because we want
2996 * to make sure that any RAID levels on a degraded FS
2997 * continue to be honored.
2999 u64 num_devices = root->fs_info->fs_devices->rw_devices +
3000 root->fs_info->fs_devices->missing_devices;
3002 if (num_devices == 1)
3003 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3004 if (num_devices < 4)
3005 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3007 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3008 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3009 BTRFS_BLOCK_GROUP_RAID10))) {
3010 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3013 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3014 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3015 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3018 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3019 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3020 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3021 (flags & BTRFS_BLOCK_GROUP_DUP)))
3022 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3026 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3028 if (flags & BTRFS_BLOCK_GROUP_DATA)
3029 flags |= root->fs_info->avail_data_alloc_bits &
3030 root->fs_info->data_alloc_profile;
3031 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3032 flags |= root->fs_info->avail_system_alloc_bits &
3033 root->fs_info->system_alloc_profile;
3034 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3035 flags |= root->fs_info->avail_metadata_alloc_bits &
3036 root->fs_info->metadata_alloc_profile;
3037 return btrfs_reduce_alloc_profile(root, flags);
3040 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3045 flags = BTRFS_BLOCK_GROUP_DATA;
3046 else if (root == root->fs_info->chunk_root)
3047 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3049 flags = BTRFS_BLOCK_GROUP_METADATA;
3051 return get_alloc_profile(root, flags);
3054 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3056 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3057 BTRFS_BLOCK_GROUP_DATA);
3061 * This will check the space that the inode allocates from to make sure we have
3062 * enough space for bytes.
3064 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3066 struct btrfs_space_info *data_sinfo;
3067 struct btrfs_root *root = BTRFS_I(inode)->root;
3069 int ret = 0, committed = 0, alloc_chunk = 1;
3071 /* make sure bytes are sectorsize aligned */
3072 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3074 if (root == root->fs_info->tree_root ||
3075 BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID) {
3080 data_sinfo = BTRFS_I(inode)->space_info;
3085 /* make sure we have enough space to handle the data first */
3086 spin_lock(&data_sinfo->lock);
3087 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3088 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3089 data_sinfo->bytes_may_use;
3091 if (used + bytes > data_sinfo->total_bytes) {
3092 struct btrfs_trans_handle *trans;
3095 * if we don't have enough free bytes in this space then we need
3096 * to alloc a new chunk.
3098 if (!data_sinfo->full && alloc_chunk) {
3101 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
3102 spin_unlock(&data_sinfo->lock);
3104 alloc_target = btrfs_get_alloc_profile(root, 1);
3105 trans = btrfs_join_transaction(root);
3107 return PTR_ERR(trans);
3109 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3110 bytes + 2 * 1024 * 1024,
3112 CHUNK_ALLOC_NO_FORCE);
3113 btrfs_end_transaction(trans, root);
3122 btrfs_set_inode_space_info(root, inode);
3123 data_sinfo = BTRFS_I(inode)->space_info;
3129 * If we have less pinned bytes than we want to allocate then
3130 * don't bother committing the transaction, it won't help us.
3132 if (data_sinfo->bytes_pinned < bytes)
3134 spin_unlock(&data_sinfo->lock);
3136 /* commit the current transaction and try again */
3139 !atomic_read(&root->fs_info->open_ioctl_trans)) {
3141 trans = btrfs_join_transaction(root);
3143 return PTR_ERR(trans);
3144 ret = btrfs_commit_transaction(trans, root);
3152 data_sinfo->bytes_may_use += bytes;
3153 spin_unlock(&data_sinfo->lock);
3159 * Called if we need to clear a data reservation for this inode.
3161 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3163 struct btrfs_root *root = BTRFS_I(inode)->root;
3164 struct btrfs_space_info *data_sinfo;
3166 /* make sure bytes are sectorsize aligned */
3167 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3169 data_sinfo = BTRFS_I(inode)->space_info;
3170 spin_lock(&data_sinfo->lock);
3171 data_sinfo->bytes_may_use -= bytes;
3172 spin_unlock(&data_sinfo->lock);
3175 static void force_metadata_allocation(struct btrfs_fs_info *info)
3177 struct list_head *head = &info->space_info;
3178 struct btrfs_space_info *found;
3181 list_for_each_entry_rcu(found, head, list) {
3182 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3183 found->force_alloc = CHUNK_ALLOC_FORCE;
3188 static int should_alloc_chunk(struct btrfs_root *root,
3189 struct btrfs_space_info *sinfo, u64 alloc_bytes,
3192 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3193 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3194 u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
3197 if (force == CHUNK_ALLOC_FORCE)
3201 * We need to take into account the global rsv because for all intents
3202 * and purposes it's used space. Don't worry about locking the
3203 * global_rsv, it doesn't change except when the transaction commits.
3205 num_allocated += global_rsv->size;
3208 * in limited mode, we want to have some free space up to
3209 * about 1% of the FS size.
3211 if (force == CHUNK_ALLOC_LIMITED) {
3212 thresh = btrfs_super_total_bytes(root->fs_info->super_copy);
3213 thresh = max_t(u64, 64 * 1024 * 1024,
3214 div_factor_fine(thresh, 1));
3216 if (num_bytes - num_allocated < thresh)
3221 * we have two similar checks here, one based on percentage
3222 * and once based on a hard number of 256MB. The idea
3223 * is that if we have a good amount of free
3224 * room, don't allocate a chunk. A good mount is
3225 * less than 80% utilized of the chunks we have allocated,
3226 * or more than 256MB free
3228 if (num_allocated + alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3231 if (num_allocated + alloc_bytes < div_factor(num_bytes, 8))
3234 thresh = btrfs_super_total_bytes(root->fs_info->super_copy);
3236 /* 256MB or 5% of the FS */
3237 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3239 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3244 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3245 struct btrfs_root *extent_root, u64 alloc_bytes,
3246 u64 flags, int force)
3248 struct btrfs_space_info *space_info;
3249 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3250 int wait_for_alloc = 0;
3253 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3255 space_info = __find_space_info(extent_root->fs_info, flags);
3257 ret = update_space_info(extent_root->fs_info, flags,
3261 BUG_ON(!space_info);
3264 spin_lock(&space_info->lock);
3265 if (space_info->force_alloc)
3266 force = space_info->force_alloc;
3267 if (space_info->full) {
3268 spin_unlock(&space_info->lock);
3272 if (!should_alloc_chunk(extent_root, space_info, alloc_bytes, force)) {
3273 spin_unlock(&space_info->lock);
3275 } else if (space_info->chunk_alloc) {
3278 space_info->chunk_alloc = 1;
3281 spin_unlock(&space_info->lock);
3283 mutex_lock(&fs_info->chunk_mutex);
3286 * The chunk_mutex is held throughout the entirety of a chunk
3287 * allocation, so once we've acquired the chunk_mutex we know that the
3288 * other guy is done and we need to recheck and see if we should
3291 if (wait_for_alloc) {
3292 mutex_unlock(&fs_info->chunk_mutex);
3298 * If we have mixed data/metadata chunks we want to make sure we keep
3299 * allocating mixed chunks instead of individual chunks.
3301 if (btrfs_mixed_space_info(space_info))
3302 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3305 * if we're doing a data chunk, go ahead and make sure that
3306 * we keep a reasonable number of metadata chunks allocated in the
3309 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3310 fs_info->data_chunk_allocations++;
3311 if (!(fs_info->data_chunk_allocations %
3312 fs_info->metadata_ratio))
3313 force_metadata_allocation(fs_info);
3316 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3317 if (ret < 0 && ret != -ENOSPC)
3320 spin_lock(&space_info->lock);
3322 space_info->full = 1;
3326 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3327 space_info->chunk_alloc = 0;
3328 spin_unlock(&space_info->lock);
3330 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3335 * shrink metadata reservation for delalloc
3337 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3338 struct btrfs_root *root, u64 to_reclaim,
3341 struct btrfs_block_rsv *block_rsv;
3342 struct btrfs_space_info *space_info;
3347 unsigned long nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3349 unsigned long progress;
3351 block_rsv = &root->fs_info->delalloc_block_rsv;
3352 space_info = block_rsv->space_info;
3355 reserved = space_info->bytes_may_use;
3356 progress = space_info->reservation_progress;
3362 if (root->fs_info->delalloc_bytes == 0) {
3365 btrfs_wait_ordered_extents(root, 0, 0);
3369 max_reclaim = min(reserved, to_reclaim);
3370 nr_pages = max_t(unsigned long, nr_pages,
3371 max_reclaim >> PAGE_CACHE_SHIFT);
3372 while (loops < 1024) {
3373 /* have the flusher threads jump in and do some IO */
3375 nr_pages = min_t(unsigned long, nr_pages,
3376 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3377 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3379 spin_lock(&space_info->lock);
3380 if (reserved > space_info->bytes_may_use)
3381 reclaimed += reserved - space_info->bytes_may_use;
3382 reserved = space_info->bytes_may_use;
3383 spin_unlock(&space_info->lock);
3387 if (reserved == 0 || reclaimed >= max_reclaim)
3390 if (trans && trans->transaction->blocked)
3393 if (wait_ordered && !trans) {
3394 btrfs_wait_ordered_extents(root, 0, 0);
3396 time_left = schedule_timeout_interruptible(1);
3398 /* We were interrupted, exit */
3403 /* we've kicked the IO a few times, if anything has been freed,
3404 * exit. There is no sense in looping here for a long time
3405 * when we really need to commit the transaction, or there are
3406 * just too many writers without enough free space
3411 if (progress != space_info->reservation_progress)
3417 return reclaimed >= to_reclaim;
3421 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
3422 * @root - the root we're allocating for
3423 * @block_rsv - the block_rsv we're allocating for
3424 * @orig_bytes - the number of bytes we want
3425 * @flush - wether or not we can flush to make our reservation
3427 * This will reserve orgi_bytes number of bytes from the space info associated
3428 * with the block_rsv. If there is not enough space it will make an attempt to
3429 * flush out space to make room. It will do this by flushing delalloc if
3430 * possible or committing the transaction. If flush is 0 then no attempts to
3431 * regain reservations will be made and this will fail if there is not enough
3434 static int reserve_metadata_bytes(struct btrfs_root *root,
3435 struct btrfs_block_rsv *block_rsv,
3436 u64 orig_bytes, int flush)
3438 struct btrfs_space_info *space_info = block_rsv->space_info;
3439 struct btrfs_trans_handle *trans;
3441 u64 num_bytes = orig_bytes;
3444 bool committed = false;
3445 bool flushing = false;
3446 bool wait_ordered = false;
3448 trans = (struct btrfs_trans_handle *)current->journal_info;
3451 spin_lock(&space_info->lock);
3453 * We only want to wait if somebody other than us is flushing and we are
3454 * actually alloed to flush.
3456 while (flush && !flushing && space_info->flush) {
3457 spin_unlock(&space_info->lock);
3459 * If we have a trans handle we can't wait because the flusher
3460 * may have to commit the transaction, which would mean we would
3461 * deadlock since we are waiting for the flusher to finish, but
3462 * hold the current transaction open.
3466 ret = wait_event_interruptible(space_info->wait,
3467 !space_info->flush);
3468 /* Must have been interrupted, return */
3472 spin_lock(&space_info->lock);
3476 used = space_info->bytes_used + space_info->bytes_reserved +
3477 space_info->bytes_pinned + space_info->bytes_readonly +
3478 space_info->bytes_may_use;
3481 * The idea here is that we've not already over-reserved the block group
3482 * then we can go ahead and save our reservation first and then start
3483 * flushing if we need to. Otherwise if we've already overcommitted
3484 * lets start flushing stuff first and then come back and try to make
3487 if (used <= space_info->total_bytes) {
3488 if (used + orig_bytes <= space_info->total_bytes) {
3489 space_info->bytes_may_use += orig_bytes;
3493 * Ok set num_bytes to orig_bytes since we aren't
3494 * overocmmitted, this way we only try and reclaim what
3497 num_bytes = orig_bytes;
3501 * Ok we're over committed, set num_bytes to the overcommitted
3502 * amount plus the amount of bytes that we need for this
3505 wait_ordered = true;
3506 num_bytes = used - space_info->total_bytes +
3507 (orig_bytes * (retries + 1));
3511 u64 profile = btrfs_get_alloc_profile(root, 0);
3515 * If we have a lot of space that's pinned, don't bother doing
3516 * the overcommit dance yet and just commit the transaction.
3518 avail = (space_info->total_bytes - space_info->bytes_used) * 8;
3520 if (space_info->bytes_pinned >= avail && flush && !trans &&
3522 space_info->flush = 1;
3524 spin_unlock(&space_info->lock);
3528 spin_lock(&root->fs_info->free_chunk_lock);
3529 avail = root->fs_info->free_chunk_space;
3532 * If we have dup, raid1 or raid10 then only half of the free
3533 * space is actually useable.
3535 if (profile & (BTRFS_BLOCK_GROUP_DUP |
3536 BTRFS_BLOCK_GROUP_RAID1 |
3537 BTRFS_BLOCK_GROUP_RAID10))
3541 * If we aren't flushing don't let us overcommit too much, say
3542 * 1/8th of the space. If we can flush, let it overcommit up to
3549 spin_unlock(&root->fs_info->free_chunk_lock);
3551 if (used + num_bytes < space_info->total_bytes + avail) {
3552 space_info->bytes_may_use += orig_bytes;
3555 wait_ordered = true;
3560 * Couldn't make our reservation, save our place so while we're trying
3561 * to reclaim space we can actually use it instead of somebody else
3562 * stealing it from us.
3566 space_info->flush = 1;
3569 spin_unlock(&space_info->lock);
3575 * We do synchronous shrinking since we don't actually unreserve
3576 * metadata until after the IO is completed.
3578 ret = shrink_delalloc(trans, root, num_bytes, wait_ordered);
3585 * So if we were overcommitted it's possible that somebody else flushed
3586 * out enough space and we simply didn't have enough space to reclaim,
3587 * so go back around and try again.
3590 wait_ordered = true;
3604 trans = btrfs_join_transaction(root);
3607 ret = btrfs_commit_transaction(trans, root);
3616 spin_lock(&space_info->lock);
3617 space_info->flush = 0;
3618 wake_up_all(&space_info->wait);
3619 spin_unlock(&space_info->lock);
3624 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3625 struct btrfs_root *root)
3627 struct btrfs_block_rsv *block_rsv = NULL;
3629 if (root->ref_cows || root == root->fs_info->csum_root)
3630 block_rsv = trans->block_rsv;
3633 block_rsv = root->block_rsv;
3636 block_rsv = &root->fs_info->empty_block_rsv;
3641 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3645 spin_lock(&block_rsv->lock);
3646 if (block_rsv->reserved >= num_bytes) {
3647 block_rsv->reserved -= num_bytes;
3648 if (block_rsv->reserved < block_rsv->size)
3649 block_rsv->full = 0;
3652 spin_unlock(&block_rsv->lock);
3656 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3657 u64 num_bytes, int update_size)
3659 spin_lock(&block_rsv->lock);
3660 block_rsv->reserved += num_bytes;
3662 block_rsv->size += num_bytes;
3663 else if (block_rsv->reserved >= block_rsv->size)
3664 block_rsv->full = 1;
3665 spin_unlock(&block_rsv->lock);
3668 static void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3669 struct btrfs_block_rsv *dest, u64 num_bytes)
3671 struct btrfs_space_info *space_info = block_rsv->space_info;
3673 spin_lock(&block_rsv->lock);
3674 if (num_bytes == (u64)-1)
3675 num_bytes = block_rsv->size;
3676 block_rsv->size -= num_bytes;
3677 if (block_rsv->reserved >= block_rsv->size) {
3678 num_bytes = block_rsv->reserved - block_rsv->size;
3679 block_rsv->reserved = block_rsv->size;
3680 block_rsv->full = 1;
3684 spin_unlock(&block_rsv->lock);
3686 if (num_bytes > 0) {
3688 spin_lock(&dest->lock);
3692 bytes_to_add = dest->size - dest->reserved;
3693 bytes_to_add = min(num_bytes, bytes_to_add);
3694 dest->reserved += bytes_to_add;
3695 if (dest->reserved >= dest->size)
3697 num_bytes -= bytes_to_add;
3699 spin_unlock(&dest->lock);
3702 spin_lock(&space_info->lock);
3703 space_info->bytes_may_use -= num_bytes;
3704 space_info->reservation_progress++;
3705 spin_unlock(&space_info->lock);
3710 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3711 struct btrfs_block_rsv *dst, u64 num_bytes)
3715 ret = block_rsv_use_bytes(src, num_bytes);
3719 block_rsv_add_bytes(dst, num_bytes, 1);
3723 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3725 memset(rsv, 0, sizeof(*rsv));
3726 spin_lock_init(&rsv->lock);
3729 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3731 struct btrfs_block_rsv *block_rsv;
3732 struct btrfs_fs_info *fs_info = root->fs_info;
3734 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3738 btrfs_init_block_rsv(block_rsv);
3739 block_rsv->space_info = __find_space_info(fs_info,
3740 BTRFS_BLOCK_GROUP_METADATA);
3744 void btrfs_free_block_rsv(struct btrfs_root *root,
3745 struct btrfs_block_rsv *rsv)
3747 btrfs_block_rsv_release(root, rsv, (u64)-1);
3751 int btrfs_block_rsv_add(struct btrfs_root *root,
3752 struct btrfs_block_rsv *block_rsv,
3760 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, 1);
3762 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3769 int btrfs_block_rsv_check(struct btrfs_root *root,
3770 struct btrfs_block_rsv *block_rsv, int min_factor)
3778 spin_lock(&block_rsv->lock);
3779 num_bytes = div_factor(block_rsv->size, min_factor);
3780 if (block_rsv->reserved >= num_bytes)
3782 spin_unlock(&block_rsv->lock);
3787 int btrfs_block_rsv_refill(struct btrfs_root *root,
3788 struct btrfs_block_rsv *block_rsv,
3797 spin_lock(&block_rsv->lock);
3798 num_bytes = min_reserved;
3799 if (block_rsv->reserved >= num_bytes)
3802 num_bytes -= block_rsv->reserved;
3803 spin_unlock(&block_rsv->lock);
3808 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, 1);
3810 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3817 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3818 struct btrfs_block_rsv *dst_rsv,
3821 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3824 void btrfs_block_rsv_release(struct btrfs_root *root,
3825 struct btrfs_block_rsv *block_rsv,
3828 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3829 if (global_rsv->full || global_rsv == block_rsv ||
3830 block_rsv->space_info != global_rsv->space_info)
3832 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3836 * helper to calculate size of global block reservation.
3837 * the desired value is sum of space used by extent tree,
3838 * checksum tree and root tree
3840 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3842 struct btrfs_space_info *sinfo;
3846 int csum_size = btrfs_super_csum_size(fs_info->super_copy);
3848 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3849 spin_lock(&sinfo->lock);
3850 data_used = sinfo->bytes_used;
3851 spin_unlock(&sinfo->lock);
3853 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3854 spin_lock(&sinfo->lock);
3855 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3857 meta_used = sinfo->bytes_used;
3858 spin_unlock(&sinfo->lock);
3860 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3862 num_bytes += div64_u64(data_used + meta_used, 50);
3864 if (num_bytes * 3 > meta_used)
3865 num_bytes = div64_u64(meta_used, 3);
3867 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3870 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3872 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3873 struct btrfs_space_info *sinfo = block_rsv->space_info;
3876 num_bytes = calc_global_metadata_size(fs_info);
3878 spin_lock(&block_rsv->lock);
3879 spin_lock(&sinfo->lock);
3881 block_rsv->size = num_bytes;
3883 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3884 sinfo->bytes_reserved + sinfo->bytes_readonly +
3885 sinfo->bytes_may_use;
3887 if (sinfo->total_bytes > num_bytes) {
3888 num_bytes = sinfo->total_bytes - num_bytes;
3889 block_rsv->reserved += num_bytes;
3890 sinfo->bytes_may_use += num_bytes;
3893 if (block_rsv->reserved >= block_rsv->size) {
3894 num_bytes = block_rsv->reserved - block_rsv->size;
3895 sinfo->bytes_may_use -= num_bytes;
3896 sinfo->reservation_progress++;
3897 block_rsv->reserved = block_rsv->size;
3898 block_rsv->full = 1;
3901 spin_unlock(&sinfo->lock);
3902 spin_unlock(&block_rsv->lock);
3905 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3907 struct btrfs_space_info *space_info;
3909 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3910 fs_info->chunk_block_rsv.space_info = space_info;
3912 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3913 fs_info->global_block_rsv.space_info = space_info;
3914 fs_info->delalloc_block_rsv.space_info = space_info;
3915 fs_info->trans_block_rsv.space_info = space_info;
3916 fs_info->empty_block_rsv.space_info = space_info;
3918 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3919 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3920 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3921 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3922 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3924 update_global_block_rsv(fs_info);
3927 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3929 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3930 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3931 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3932 WARN_ON(fs_info->trans_block_rsv.size > 0);
3933 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3934 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3935 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3938 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3939 struct btrfs_root *root)
3941 if (!trans->bytes_reserved)
3944 btrfs_block_rsv_release(root, trans->block_rsv, trans->bytes_reserved);
3945 trans->bytes_reserved = 0;
3948 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3949 struct inode *inode)
3951 struct btrfs_root *root = BTRFS_I(inode)->root;
3952 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3953 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3956 * We need to hold space in order to delete our orphan item once we've
3957 * added it, so this takes the reservation so we can release it later
3958 * when we are truly done with the orphan item.
3960 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
3961 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3964 void btrfs_orphan_release_metadata(struct inode *inode)
3966 struct btrfs_root *root = BTRFS_I(inode)->root;
3967 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
3968 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3971 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3972 struct btrfs_pending_snapshot *pending)
3974 struct btrfs_root *root = pending->root;
3975 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3976 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3978 * two for root back/forward refs, two for directory entries
3979 * and one for root of the snapshot.
3981 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 5);
3982 dst_rsv->space_info = src_rsv->space_info;
3983 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3987 * drop_outstanding_extent - drop an outstanding extent
3988 * @inode: the inode we're dropping the extent for
3990 * This is called when we are freeing up an outstanding extent, either called
3991 * after an error or after an extent is written. This will return the number of
3992 * reserved extents that need to be freed. This must be called with
3993 * BTRFS_I(inode)->lock held.
3995 static unsigned drop_outstanding_extent(struct inode *inode)
3997 unsigned dropped_extents = 0;
3999 BUG_ON(!BTRFS_I(inode)->outstanding_extents);
4000 BTRFS_I(inode)->outstanding_extents--;
4003 * If we have more or the same amount of outsanding extents than we have
4004 * reserved then we need to leave the reserved extents count alone.
4006 if (BTRFS_I(inode)->outstanding_extents >=
4007 BTRFS_I(inode)->reserved_extents)
4010 dropped_extents = BTRFS_I(inode)->reserved_extents -
4011 BTRFS_I(inode)->outstanding_extents;
4012 BTRFS_I(inode)->reserved_extents -= dropped_extents;
4013 return dropped_extents;
4017 * calc_csum_metadata_size - return the amount of metada space that must be
4018 * reserved/free'd for the given bytes.
4019 * @inode: the inode we're manipulating
4020 * @num_bytes: the number of bytes in question
4021 * @reserve: 1 if we are reserving space, 0 if we are freeing space
4023 * This adjusts the number of csum_bytes in the inode and then returns the
4024 * correct amount of metadata that must either be reserved or freed. We
4025 * calculate how many checksums we can fit into one leaf and then divide the
4026 * number of bytes that will need to be checksumed by this value to figure out
4027 * how many checksums will be required. If we are adding bytes then the number
4028 * may go up and we will return the number of additional bytes that must be
4029 * reserved. If it is going down we will return the number of bytes that must
4032 * This must be called with BTRFS_I(inode)->lock held.
4034 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes,
4037 struct btrfs_root *root = BTRFS_I(inode)->root;
4039 int num_csums_per_leaf;
4043 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM &&
4044 BTRFS_I(inode)->csum_bytes == 0)
4047 old_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
4049 BTRFS_I(inode)->csum_bytes += num_bytes;
4051 BTRFS_I(inode)->csum_bytes -= num_bytes;
4052 csum_size = BTRFS_LEAF_DATA_SIZE(root) - sizeof(struct btrfs_item);
4053 num_csums_per_leaf = (int)div64_u64(csum_size,
4054 sizeof(struct btrfs_csum_item) +
4055 sizeof(struct btrfs_disk_key));
4056 num_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
4057 num_csums = num_csums + num_csums_per_leaf - 1;
4058 num_csums = num_csums / num_csums_per_leaf;
4060 old_csums = old_csums + num_csums_per_leaf - 1;
4061 old_csums = old_csums / num_csums_per_leaf;
4063 /* No change, no need to reserve more */
4064 if (old_csums == num_csums)
4068 return btrfs_calc_trans_metadata_size(root,
4069 num_csums - old_csums);
4071 return btrfs_calc_trans_metadata_size(root, old_csums - num_csums);
4074 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
4076 struct btrfs_root *root = BTRFS_I(inode)->root;
4077 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
4079 unsigned nr_extents = 0;
4083 if (btrfs_is_free_space_inode(root, inode))
4086 if (flush && btrfs_transaction_in_commit(root->fs_info))
4087 schedule_timeout(1);
4089 num_bytes = ALIGN(num_bytes, root->sectorsize);
4091 spin_lock(&BTRFS_I(inode)->lock);
4092 BTRFS_I(inode)->outstanding_extents++;
4094 if (BTRFS_I(inode)->outstanding_extents >
4095 BTRFS_I(inode)->reserved_extents) {
4096 nr_extents = BTRFS_I(inode)->outstanding_extents -
4097 BTRFS_I(inode)->reserved_extents;
4098 BTRFS_I(inode)->reserved_extents += nr_extents;
4100 to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
4102 to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
4103 spin_unlock(&BTRFS_I(inode)->lock);
4105 ret = reserve_metadata_bytes(root, block_rsv, to_reserve, flush);
4110 spin_lock(&BTRFS_I(inode)->lock);
4111 dropped = drop_outstanding_extent(inode);
4112 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
4113 spin_unlock(&BTRFS_I(inode)->lock);
4114 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4117 * Somebody could have come in and twiddled with the
4118 * reservation, so if we have to free more than we would have
4119 * reserved from this reservation go ahead and release those
4122 to_free -= to_reserve;
4124 btrfs_block_rsv_release(root, block_rsv, to_free);
4128 block_rsv_add_bytes(block_rsv, to_reserve, 1);
4134 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
4135 * @inode: the inode to release the reservation for
4136 * @num_bytes: the number of bytes we're releasing
4138 * This will release the metadata reservation for an inode. This can be called
4139 * once we complete IO for a given set of bytes to release their metadata
4142 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4144 struct btrfs_root *root = BTRFS_I(inode)->root;
4148 num_bytes = ALIGN(num_bytes, root->sectorsize);
4149 spin_lock(&BTRFS_I(inode)->lock);
4150 dropped = drop_outstanding_extent(inode);
4152 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
4153 spin_unlock(&BTRFS_I(inode)->lock);
4155 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4157 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4162 * btrfs_delalloc_reserve_space - reserve data and metadata space for delalloc
4163 * @inode: inode we're writing to
4164 * @num_bytes: the number of bytes we want to allocate
4166 * This will do the following things
4168 * o reserve space in the data space info for num_bytes
4169 * o reserve space in the metadata space info based on number of outstanding
4170 * extents and how much csums will be needed
4171 * o add to the inodes ->delalloc_bytes
4172 * o add it to the fs_info's delalloc inodes list.
4174 * This will return 0 for success and -ENOSPC if there is no space left.
4176 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4180 ret = btrfs_check_data_free_space(inode, num_bytes);
4184 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4186 btrfs_free_reserved_data_space(inode, num_bytes);
4194 * btrfs_delalloc_release_space - release data and metadata space for delalloc
4195 * @inode: inode we're releasing space for
4196 * @num_bytes: the number of bytes we want to free up
4198 * This must be matched with a call to btrfs_delalloc_reserve_space. This is
4199 * called in the case that we don't need the metadata AND data reservations
4200 * anymore. So if there is an error or we insert an inline extent.
4202 * This function will release the metadata space that was not used and will
4203 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
4204 * list if there are no delalloc bytes left.
4206 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4208 btrfs_delalloc_release_metadata(inode, num_bytes);
4209 btrfs_free_reserved_data_space(inode, num_bytes);
4212 static int update_block_group(struct btrfs_trans_handle *trans,
4213 struct btrfs_root *root,
4214 u64 bytenr, u64 num_bytes, int alloc)
4216 struct btrfs_block_group_cache *cache = NULL;
4217 struct btrfs_fs_info *info = root->fs_info;
4218 u64 total = num_bytes;
4223 /* block accounting for super block */
4224 spin_lock(&info->delalloc_lock);
4225 old_val = btrfs_super_bytes_used(info->super_copy);
4227 old_val += num_bytes;
4229 old_val -= num_bytes;
4230 btrfs_set_super_bytes_used(info->super_copy, old_val);
4231 spin_unlock(&info->delalloc_lock);
4234 cache = btrfs_lookup_block_group(info, bytenr);
4237 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4238 BTRFS_BLOCK_GROUP_RAID1 |
4239 BTRFS_BLOCK_GROUP_RAID10))
4244 * If this block group has free space cache written out, we
4245 * need to make sure to load it if we are removing space. This
4246 * is because we need the unpinning stage to actually add the
4247 * space back to the block group, otherwise we will leak space.
4249 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4250 cache_block_group(cache, trans, NULL, 1);
4252 byte_in_group = bytenr - cache->key.objectid;
4253 WARN_ON(byte_in_group > cache->key.offset);
4255 spin_lock(&cache->space_info->lock);
4256 spin_lock(&cache->lock);
4258 if (btrfs_test_opt(root, SPACE_CACHE) &&
4259 cache->disk_cache_state < BTRFS_DC_CLEAR)
4260 cache->disk_cache_state = BTRFS_DC_CLEAR;
4263 old_val = btrfs_block_group_used(&cache->item);
4264 num_bytes = min(total, cache->key.offset - byte_in_group);
4266 old_val += num_bytes;
4267 btrfs_set_block_group_used(&cache->item, old_val);
4268 cache->reserved -= num_bytes;
4269 cache->space_info->bytes_reserved -= num_bytes;
4270 cache->space_info->bytes_used += num_bytes;
4271 cache->space_info->disk_used += num_bytes * factor;
4272 spin_unlock(&cache->lock);
4273 spin_unlock(&cache->space_info->lock);
4275 old_val -= num_bytes;
4276 btrfs_set_block_group_used(&cache->item, old_val);
4277 cache->pinned += num_bytes;
4278 cache->space_info->bytes_pinned += num_bytes;
4279 cache->space_info->bytes_used -= num_bytes;
4280 cache->space_info->disk_used -= num_bytes * factor;
4281 spin_unlock(&cache->lock);
4282 spin_unlock(&cache->space_info->lock);
4284 set_extent_dirty(info->pinned_extents,
4285 bytenr, bytenr + num_bytes - 1,
4286 GFP_NOFS | __GFP_NOFAIL);
4288 btrfs_put_block_group(cache);
4290 bytenr += num_bytes;
4295 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4297 struct btrfs_block_group_cache *cache;
4300 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4304 bytenr = cache->key.objectid;
4305 btrfs_put_block_group(cache);
4310 static int pin_down_extent(struct btrfs_root *root,
4311 struct btrfs_block_group_cache *cache,
4312 u64 bytenr, u64 num_bytes, int reserved)
4314 spin_lock(&cache->space_info->lock);
4315 spin_lock(&cache->lock);
4316 cache->pinned += num_bytes;
4317 cache->space_info->bytes_pinned += num_bytes;
4319 cache->reserved -= num_bytes;
4320 cache->space_info->bytes_reserved -= num_bytes;
4322 spin_unlock(&cache->lock);
4323 spin_unlock(&cache->space_info->lock);
4325 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4326 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4331 * this function must be called within transaction
4333 int btrfs_pin_extent(struct btrfs_root *root,
4334 u64 bytenr, u64 num_bytes, int reserved)
4336 struct btrfs_block_group_cache *cache;
4338 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4341 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4343 btrfs_put_block_group(cache);
4348 * this function must be called within transaction
4350 int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans,
4351 struct btrfs_root *root,
4352 u64 bytenr, u64 num_bytes)
4354 struct btrfs_block_group_cache *cache;
4356 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4360 * pull in the free space cache (if any) so that our pin
4361 * removes the free space from the cache. We have load_only set
4362 * to one because the slow code to read in the free extents does check
4363 * the pinned extents.
4365 cache_block_group(cache, trans, root, 1);
4367 pin_down_extent(root, cache, bytenr, num_bytes, 0);
4369 /* remove us from the free space cache (if we're there at all) */
4370 btrfs_remove_free_space(cache, bytenr, num_bytes);
4371 btrfs_put_block_group(cache);
4376 * btrfs_update_reserved_bytes - update the block_group and space info counters
4377 * @cache: The cache we are manipulating
4378 * @num_bytes: The number of bytes in question
4379 * @reserve: One of the reservation enums
4381 * This is called by the allocator when it reserves space, or by somebody who is
4382 * freeing space that was never actually used on disk. For example if you
4383 * reserve some space for a new leaf in transaction A and before transaction A
4384 * commits you free that leaf, you call this with reserve set to 0 in order to
4385 * clear the reservation.
4387 * Metadata reservations should be called with RESERVE_ALLOC so we do the proper
4388 * ENOSPC accounting. For data we handle the reservation through clearing the
4389 * delalloc bits in the io_tree. We have to do this since we could end up
4390 * allocating less disk space for the amount of data we have reserved in the
4391 * case of compression.
4393 * If this is a reservation and the block group has become read only we cannot
4394 * make the reservation and return -EAGAIN, otherwise this function always
4397 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
4398 u64 num_bytes, int reserve)
4400 struct btrfs_space_info *space_info = cache->space_info;
4402 spin_lock(&space_info->lock);
4403 spin_lock(&cache->lock);
4404 if (reserve != RESERVE_FREE) {
4408 cache->reserved += num_bytes;
4409 space_info->bytes_reserved += num_bytes;
4410 if (reserve == RESERVE_ALLOC) {
4411 BUG_ON(space_info->bytes_may_use < num_bytes);
4412 space_info->bytes_may_use -= num_bytes;
4417 space_info->bytes_readonly += num_bytes;
4418 cache->reserved -= num_bytes;
4419 space_info->bytes_reserved -= num_bytes;
4420 space_info->reservation_progress++;
4422 spin_unlock(&cache->lock);
4423 spin_unlock(&space_info->lock);
4427 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4428 struct btrfs_root *root)
4430 struct btrfs_fs_info *fs_info = root->fs_info;
4431 struct btrfs_caching_control *next;
4432 struct btrfs_caching_control *caching_ctl;
4433 struct btrfs_block_group_cache *cache;
4435 down_write(&fs_info->extent_commit_sem);
4437 list_for_each_entry_safe(caching_ctl, next,
4438 &fs_info->caching_block_groups, list) {
4439 cache = caching_ctl->block_group;
4440 if (block_group_cache_done(cache)) {
4441 cache->last_byte_to_unpin = (u64)-1;
4442 list_del_init(&caching_ctl->list);
4443 put_caching_control(caching_ctl);
4445 cache->last_byte_to_unpin = caching_ctl->progress;
4449 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4450 fs_info->pinned_extents = &fs_info->freed_extents[1];
4452 fs_info->pinned_extents = &fs_info->freed_extents[0];
4454 up_write(&fs_info->extent_commit_sem);
4456 update_global_block_rsv(fs_info);
4460 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4462 struct btrfs_fs_info *fs_info = root->fs_info;
4463 struct btrfs_block_group_cache *cache = NULL;
4466 while (start <= end) {
4468 start >= cache->key.objectid + cache->key.offset) {
4470 btrfs_put_block_group(cache);
4471 cache = btrfs_lookup_block_group(fs_info, start);
4475 len = cache->key.objectid + cache->key.offset - start;
4476 len = min(len, end + 1 - start);
4478 if (start < cache->last_byte_to_unpin) {
4479 len = min(len, cache->last_byte_to_unpin - start);
4480 btrfs_add_free_space(cache, start, len);
4485 spin_lock(&cache->space_info->lock);
4486 spin_lock(&cache->lock);
4487 cache->pinned -= len;
4488 cache->space_info->bytes_pinned -= len;
4490 cache->space_info->bytes_readonly += len;
4491 spin_unlock(&cache->lock);
4492 spin_unlock(&cache->space_info->lock);
4496 btrfs_put_block_group(cache);
4500 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4501 struct btrfs_root *root)
4503 struct btrfs_fs_info *fs_info = root->fs_info;
4504 struct extent_io_tree *unpin;
4509 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4510 unpin = &fs_info->freed_extents[1];
4512 unpin = &fs_info->freed_extents[0];
4515 ret = find_first_extent_bit(unpin, 0, &start, &end,
4520 if (btrfs_test_opt(root, DISCARD))
4521 ret = btrfs_discard_extent(root, start,
4522 end + 1 - start, NULL);
4524 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4525 unpin_extent_range(root, start, end);
4532 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4533 struct btrfs_root *root,
4534 u64 bytenr, u64 num_bytes, u64 parent,
4535 u64 root_objectid, u64 owner_objectid,
4536 u64 owner_offset, int refs_to_drop,
4537 struct btrfs_delayed_extent_op *extent_op)
4539 struct btrfs_key key;
4540 struct btrfs_path *path;
4541 struct btrfs_fs_info *info = root->fs_info;
4542 struct btrfs_root *extent_root = info->extent_root;
4543 struct extent_buffer *leaf;
4544 struct btrfs_extent_item *ei;
4545 struct btrfs_extent_inline_ref *iref;
4548 int extent_slot = 0;
4549 int found_extent = 0;
4554 path = btrfs_alloc_path();
4559 path->leave_spinning = 1;
4561 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4562 BUG_ON(!is_data && refs_to_drop != 1);
4564 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4565 bytenr, num_bytes, parent,
4566 root_objectid, owner_objectid,
4569 extent_slot = path->slots[0];
4570 while (extent_slot >= 0) {
4571 btrfs_item_key_to_cpu(path->nodes[0], &key,
4573 if (key.objectid != bytenr)
4575 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4576 key.offset == num_bytes) {
4580 if (path->slots[0] - extent_slot > 5)
4584 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4585 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4586 if (found_extent && item_size < sizeof(*ei))
4589 if (!found_extent) {
4591 ret = remove_extent_backref(trans, extent_root, path,
4595 btrfs_release_path(path);
4596 path->leave_spinning = 1;
4598 key.objectid = bytenr;
4599 key.type = BTRFS_EXTENT_ITEM_KEY;
4600 key.offset = num_bytes;
4602 ret = btrfs_search_slot(trans, extent_root,
4605 printk(KERN_ERR "umm, got %d back from search"
4606 ", was looking for %llu\n", ret,
4607 (unsigned long long)bytenr);
4609 btrfs_print_leaf(extent_root,
4613 extent_slot = path->slots[0];
4616 btrfs_print_leaf(extent_root, path->nodes[0]);
4618 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4619 "parent %llu root %llu owner %llu offset %llu\n",
4620 (unsigned long long)bytenr,
4621 (unsigned long long)parent,
4622 (unsigned long long)root_objectid,
4623 (unsigned long long)owner_objectid,
4624 (unsigned long long)owner_offset);
4627 leaf = path->nodes[0];
4628 item_size = btrfs_item_size_nr(leaf, extent_slot);
4629 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4630 if (item_size < sizeof(*ei)) {
4631 BUG_ON(found_extent || extent_slot != path->slots[0]);
4632 ret = convert_extent_item_v0(trans, extent_root, path,
4636 btrfs_release_path(path);
4637 path->leave_spinning = 1;
4639 key.objectid = bytenr;
4640 key.type = BTRFS_EXTENT_ITEM_KEY;
4641 key.offset = num_bytes;
4643 ret = btrfs_search_slot(trans, extent_root, &key, path,
4646 printk(KERN_ERR "umm, got %d back from search"
4647 ", was looking for %llu\n", ret,
4648 (unsigned long long)bytenr);
4649 btrfs_print_leaf(extent_root, path->nodes[0]);
4652 extent_slot = path->slots[0];
4653 leaf = path->nodes[0];
4654 item_size = btrfs_item_size_nr(leaf, extent_slot);
4657 BUG_ON(item_size < sizeof(*ei));
4658 ei = btrfs_item_ptr(leaf, extent_slot,
4659 struct btrfs_extent_item);
4660 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4661 struct btrfs_tree_block_info *bi;
4662 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4663 bi = (struct btrfs_tree_block_info *)(ei + 1);
4664 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4667 refs = btrfs_extent_refs(leaf, ei);
4668 BUG_ON(refs < refs_to_drop);
4669 refs -= refs_to_drop;
4673 __run_delayed_extent_op(extent_op, leaf, ei);
4675 * In the case of inline back ref, reference count will
4676 * be updated by remove_extent_backref
4679 BUG_ON(!found_extent);
4681 btrfs_set_extent_refs(leaf, ei, refs);
4682 btrfs_mark_buffer_dirty(leaf);
4685 ret = remove_extent_backref(trans, extent_root, path,
4692 BUG_ON(is_data && refs_to_drop !=
4693 extent_data_ref_count(root, path, iref));
4695 BUG_ON(path->slots[0] != extent_slot);
4697 BUG_ON(path->slots[0] != extent_slot + 1);
4698 path->slots[0] = extent_slot;
4703 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4706 btrfs_release_path(path);
4709 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4712 invalidate_mapping_pages(info->btree_inode->i_mapping,
4713 bytenr >> PAGE_CACHE_SHIFT,
4714 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4717 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4720 btrfs_free_path(path);
4725 * when we free an block, it is possible (and likely) that we free the last
4726 * delayed ref for that extent as well. This searches the delayed ref tree for
4727 * a given extent, and if there are no other delayed refs to be processed, it
4728 * removes it from the tree.
4730 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4731 struct btrfs_root *root, u64 bytenr)
4733 struct btrfs_delayed_ref_head *head;
4734 struct btrfs_delayed_ref_root *delayed_refs;
4735 struct btrfs_delayed_ref_node *ref;
4736 struct rb_node *node;
4739 delayed_refs = &trans->transaction->delayed_refs;
4740 spin_lock(&delayed_refs->lock);
4741 head = btrfs_find_delayed_ref_head(trans, bytenr);
4745 node = rb_prev(&head->node.rb_node);
4749 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4751 /* there are still entries for this ref, we can't drop it */
4752 if (ref->bytenr == bytenr)
4755 if (head->extent_op) {
4756 if (!head->must_insert_reserved)
4758 kfree(head->extent_op);
4759 head->extent_op = NULL;
4763 * waiting for the lock here would deadlock. If someone else has it
4764 * locked they are already in the process of dropping it anyway
4766 if (!mutex_trylock(&head->mutex))
4770 * at this point we have a head with no other entries. Go
4771 * ahead and process it.
4773 head->node.in_tree = 0;
4774 rb_erase(&head->node.rb_node, &delayed_refs->root);
4776 delayed_refs->num_entries--;
4779 * we don't take a ref on the node because we're removing it from the
4780 * tree, so we just steal the ref the tree was holding.
4782 delayed_refs->num_heads--;
4783 if (list_empty(&head->cluster))
4784 delayed_refs->num_heads_ready--;
4786 list_del_init(&head->cluster);
4787 spin_unlock(&delayed_refs->lock);
4789 BUG_ON(head->extent_op);
4790 if (head->must_insert_reserved)
4793 mutex_unlock(&head->mutex);
4794 btrfs_put_delayed_ref(&head->node);
4797 spin_unlock(&delayed_refs->lock);
4801 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4802 struct btrfs_root *root,
4803 struct extent_buffer *buf,
4804 u64 parent, int last_ref)
4806 struct btrfs_block_group_cache *cache = NULL;
4809 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4810 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4811 parent, root->root_key.objectid,
4812 btrfs_header_level(buf),
4813 BTRFS_DROP_DELAYED_REF, NULL);
4820 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4822 if (btrfs_header_generation(buf) == trans->transid) {
4823 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4824 ret = check_ref_cleanup(trans, root, buf->start);
4829 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4830 pin_down_extent(root, cache, buf->start, buf->len, 1);
4834 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4836 btrfs_add_free_space(cache, buf->start, buf->len);
4837 btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE);
4841 * Deleting the buffer, clear the corrupt flag since it doesn't matter
4844 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
4845 btrfs_put_block_group(cache);
4848 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4849 struct btrfs_root *root,
4850 u64 bytenr, u64 num_bytes, u64 parent,
4851 u64 root_objectid, u64 owner, u64 offset)
4856 * tree log blocks never actually go into the extent allocation
4857 * tree, just update pinning info and exit early.
4859 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4860 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4861 /* unlocks the pinned mutex */
4862 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4864 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4865 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4866 parent, root_objectid, (int)owner,
4867 BTRFS_DROP_DELAYED_REF, NULL);
4870 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4871 parent, root_objectid, owner,
4872 offset, BTRFS_DROP_DELAYED_REF, NULL);
4878 static u64 stripe_align(struct btrfs_root *root, u64 val)
4880 u64 mask = ((u64)root->stripesize - 1);
4881 u64 ret = (val + mask) & ~mask;
4886 * when we wait for progress in the block group caching, its because
4887 * our allocation attempt failed at least once. So, we must sleep
4888 * and let some progress happen before we try again.
4890 * This function will sleep at least once waiting for new free space to
4891 * show up, and then it will check the block group free space numbers
4892 * for our min num_bytes. Another option is to have it go ahead
4893 * and look in the rbtree for a free extent of a given size, but this
4897 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4900 struct btrfs_caching_control *caching_ctl;
4903 caching_ctl = get_caching_control(cache);
4907 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4908 (cache->free_space_ctl->free_space >= num_bytes));
4910 put_caching_control(caching_ctl);
4915 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4917 struct btrfs_caching_control *caching_ctl;
4920 caching_ctl = get_caching_control(cache);
4924 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4926 put_caching_control(caching_ctl);
4930 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4933 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4935 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4937 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4939 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4946 enum btrfs_loop_type {
4947 LOOP_FIND_IDEAL = 0,
4948 LOOP_CACHING_NOWAIT = 1,
4949 LOOP_CACHING_WAIT = 2,
4950 LOOP_ALLOC_CHUNK = 3,
4951 LOOP_NO_EMPTY_SIZE = 4,
4955 * walks the btree of allocated extents and find a hole of a given size.
4956 * The key ins is changed to record the hole:
4957 * ins->objectid == block start
4958 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4959 * ins->offset == number of blocks
4960 * Any available blocks before search_start are skipped.
4962 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4963 struct btrfs_root *orig_root,
4964 u64 num_bytes, u64 empty_size,
4965 u64 search_start, u64 search_end,
4966 u64 hint_byte, struct btrfs_key *ins,
4970 struct btrfs_root *root = orig_root->fs_info->extent_root;
4971 struct btrfs_free_cluster *last_ptr = NULL;
4972 struct btrfs_block_group_cache *block_group = NULL;
4973 int empty_cluster = 2 * 1024 * 1024;
4974 int allowed_chunk_alloc = 0;
4975 int done_chunk_alloc = 0;
4976 struct btrfs_space_info *space_info;
4977 int last_ptr_loop = 0;
4980 int alloc_type = (data & BTRFS_BLOCK_GROUP_DATA) ?
4981 RESERVE_ALLOC_NO_ACCOUNT : RESERVE_ALLOC;
4982 bool found_uncached_bg = false;
4983 bool failed_cluster_refill = false;
4984 bool failed_alloc = false;
4985 bool use_cluster = true;
4986 bool have_caching_bg = false;
4987 u64 ideal_cache_percent = 0;
4988 u64 ideal_cache_offset = 0;
4990 WARN_ON(num_bytes < root->sectorsize);
4991 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4995 space_info = __find_space_info(root->fs_info, data);
4997 printk(KERN_ERR "No space info for %llu\n", data);
5002 * If the space info is for both data and metadata it means we have a
5003 * small filesystem and we can't use the clustering stuff.
5005 if (btrfs_mixed_space_info(space_info))
5006 use_cluster = false;
5008 if (orig_root->ref_cows || empty_size)
5009 allowed_chunk_alloc = 1;
5011 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
5012 last_ptr = &root->fs_info->meta_alloc_cluster;
5013 if (!btrfs_test_opt(root, SSD))
5014 empty_cluster = 64 * 1024;
5017 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
5018 btrfs_test_opt(root, SSD)) {
5019 last_ptr = &root->fs_info->data_alloc_cluster;
5023 spin_lock(&last_ptr->lock);
5024 if (last_ptr->block_group)
5025 hint_byte = last_ptr->window_start;
5026 spin_unlock(&last_ptr->lock);
5029 search_start = max(search_start, first_logical_byte(root, 0));
5030 search_start = max(search_start, hint_byte);
5035 if (search_start == hint_byte) {
5037 block_group = btrfs_lookup_block_group(root->fs_info,
5040 * we don't want to use the block group if it doesn't match our
5041 * allocation bits, or if its not cached.
5043 * However if we are re-searching with an ideal block group
5044 * picked out then we don't care that the block group is cached.
5046 if (block_group && block_group_bits(block_group, data) &&
5047 (block_group->cached != BTRFS_CACHE_NO ||
5048 search_start == ideal_cache_offset)) {
5049 down_read(&space_info->groups_sem);
5050 if (list_empty(&block_group->list) ||
5053 * someone is removing this block group,
5054 * we can't jump into the have_block_group
5055 * target because our list pointers are not
5058 btrfs_put_block_group(block_group);
5059 up_read(&space_info->groups_sem);
5061 index = get_block_group_index(block_group);
5062 goto have_block_group;
5064 } else if (block_group) {
5065 btrfs_put_block_group(block_group);
5069 have_caching_bg = false;
5070 down_read(&space_info->groups_sem);
5071 list_for_each_entry(block_group, &space_info->block_groups[index],
5076 btrfs_get_block_group(block_group);
5077 search_start = block_group->key.objectid;
5080 * this can happen if we end up cycling through all the
5081 * raid types, but we want to make sure we only allocate
5082 * for the proper type.
5084 if (!block_group_bits(block_group, data)) {
5085 u64 extra = BTRFS_BLOCK_GROUP_DUP |
5086 BTRFS_BLOCK_GROUP_RAID1 |
5087 BTRFS_BLOCK_GROUP_RAID10;
5090 * if they asked for extra copies and this block group
5091 * doesn't provide them, bail. This does allow us to
5092 * fill raid0 from raid1.
5094 if ((data & extra) && !(block_group->flags & extra))
5099 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
5102 ret = cache_block_group(block_group, trans,
5104 if (block_group->cached == BTRFS_CACHE_FINISHED)
5105 goto have_block_group;
5107 free_percent = btrfs_block_group_used(&block_group->item);
5108 free_percent *= 100;
5109 free_percent = div64_u64(free_percent,
5110 block_group->key.offset);
5111 free_percent = 100 - free_percent;
5112 if (free_percent > ideal_cache_percent &&
5113 likely(!block_group->ro)) {
5114 ideal_cache_offset = block_group->key.objectid;
5115 ideal_cache_percent = free_percent;
5119 * The caching workers are limited to 2 threads, so we
5120 * can queue as much work as we care to.
5122 if (loop > LOOP_FIND_IDEAL) {
5123 ret = cache_block_group(block_group, trans,
5127 found_uncached_bg = true;
5130 * If loop is set for cached only, try the next block
5133 if (loop == LOOP_FIND_IDEAL)
5137 cached = block_group_cache_done(block_group);
5138 if (unlikely(!cached))
5139 found_uncached_bg = true;
5141 if (unlikely(block_group->ro))
5144 spin_lock(&block_group->free_space_ctl->tree_lock);
5146 block_group->free_space_ctl->free_space <
5147 num_bytes + empty_size) {
5148 spin_unlock(&block_group->free_space_ctl->tree_lock);
5151 spin_unlock(&block_group->free_space_ctl->tree_lock);
5154 * Ok we want to try and use the cluster allocator, so lets look
5155 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
5156 * have tried the cluster allocator plenty of times at this
5157 * point and not have found anything, so we are likely way too
5158 * fragmented for the clustering stuff to find anything, so lets
5159 * just skip it and let the allocator find whatever block it can
5162 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
5164 * the refill lock keeps out other
5165 * people trying to start a new cluster
5167 spin_lock(&last_ptr->refill_lock);
5168 if (last_ptr->block_group &&
5169 (last_ptr->block_group->ro ||
5170 !block_group_bits(last_ptr->block_group, data))) {
5172 goto refill_cluster;
5175 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5176 num_bytes, search_start);
5178 /* we have a block, we're done */
5179 spin_unlock(&last_ptr->refill_lock);
5183 spin_lock(&last_ptr->lock);
5185 * whoops, this cluster doesn't actually point to
5186 * this block group. Get a ref on the block
5187 * group is does point to and try again
5189 if (!last_ptr_loop && last_ptr->block_group &&
5190 last_ptr->block_group != block_group &&
5192 get_block_group_index(last_ptr->block_group)) {
5194 btrfs_put_block_group(block_group);
5195 block_group = last_ptr->block_group;
5196 btrfs_get_block_group(block_group);
5197 spin_unlock(&last_ptr->lock);
5198 spin_unlock(&last_ptr->refill_lock);
5201 search_start = block_group->key.objectid;
5203 * we know this block group is properly
5204 * in the list because
5205 * btrfs_remove_block_group, drops the
5206 * cluster before it removes the block
5207 * group from the list
5209 goto have_block_group;
5211 spin_unlock(&last_ptr->lock);
5214 * this cluster didn't work out, free it and
5217 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5221 /* allocate a cluster in this block group */
5222 ret = btrfs_find_space_cluster(trans, root,
5223 block_group, last_ptr,
5225 empty_cluster + empty_size);
5228 * now pull our allocation out of this
5231 offset = btrfs_alloc_from_cluster(block_group,
5232 last_ptr, num_bytes,
5235 /* we found one, proceed */
5236 spin_unlock(&last_ptr->refill_lock);
5239 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5240 && !failed_cluster_refill) {
5241 spin_unlock(&last_ptr->refill_lock);
5243 failed_cluster_refill = true;
5244 wait_block_group_cache_progress(block_group,
5245 num_bytes + empty_cluster + empty_size);
5246 goto have_block_group;
5250 * at this point we either didn't find a cluster
5251 * or we weren't able to allocate a block from our
5252 * cluster. Free the cluster we've been trying
5253 * to use, and go to the next block group
5255 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5256 spin_unlock(&last_ptr->refill_lock);
5260 offset = btrfs_find_space_for_alloc(block_group, search_start,
5261 num_bytes, empty_size);
5263 * If we didn't find a chunk, and we haven't failed on this
5264 * block group before, and this block group is in the middle of
5265 * caching and we are ok with waiting, then go ahead and wait
5266 * for progress to be made, and set failed_alloc to true.
5268 * If failed_alloc is true then we've already waited on this
5269 * block group once and should move on to the next block group.
5271 if (!offset && !failed_alloc && !cached &&
5272 loop > LOOP_CACHING_NOWAIT) {
5273 wait_block_group_cache_progress(block_group,
5274 num_bytes + empty_size);
5275 failed_alloc = true;
5276 goto have_block_group;
5277 } else if (!offset) {
5279 have_caching_bg = true;
5283 search_start = stripe_align(root, offset);
5284 /* move on to the next group */
5285 if (search_start + num_bytes >= search_end) {
5286 btrfs_add_free_space(block_group, offset, num_bytes);
5290 /* move on to the next group */
5291 if (search_start + num_bytes >
5292 block_group->key.objectid + block_group->key.offset) {
5293 btrfs_add_free_space(block_group, offset, num_bytes);
5297 ins->objectid = search_start;
5298 ins->offset = num_bytes;
5300 if (offset < search_start)
5301 btrfs_add_free_space(block_group, offset,
5302 search_start - offset);
5303 BUG_ON(offset > search_start);
5305 ret = btrfs_update_reserved_bytes(block_group, num_bytes,
5307 if (ret == -EAGAIN) {
5308 btrfs_add_free_space(block_group, offset, num_bytes);
5312 /* we are all good, lets return */
5313 ins->objectid = search_start;
5314 ins->offset = num_bytes;
5316 if (offset < search_start)
5317 btrfs_add_free_space(block_group, offset,
5318 search_start - offset);
5319 BUG_ON(offset > search_start);
5320 btrfs_put_block_group(block_group);
5323 failed_cluster_refill = false;
5324 failed_alloc = false;
5325 BUG_ON(index != get_block_group_index(block_group));
5326 btrfs_put_block_group(block_group);
5328 up_read(&space_info->groups_sem);
5330 if (!ins->objectid && loop >= LOOP_CACHING_WAIT && have_caching_bg)
5333 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5336 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5337 * for them to make caching progress. Also
5338 * determine the best possible bg to cache
5339 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5340 * caching kthreads as we move along
5341 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5342 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5343 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5346 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE) {
5348 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5349 found_uncached_bg = false;
5351 if (!ideal_cache_percent)
5355 * 1 of the following 2 things have happened so far
5357 * 1) We found an ideal block group for caching that
5358 * is mostly full and will cache quickly, so we might
5359 * as well wait for it.
5361 * 2) We searched for cached only and we didn't find
5362 * anything, and we didn't start any caching kthreads
5363 * either, so chances are we will loop through and
5364 * start a couple caching kthreads, and then come back
5365 * around and just wait for them. This will be slower
5366 * because we will have 2 caching kthreads reading at
5367 * the same time when we could have just started one
5368 * and waited for it to get far enough to give us an
5369 * allocation, so go ahead and go to the wait caching
5372 loop = LOOP_CACHING_WAIT;
5373 search_start = ideal_cache_offset;
5374 ideal_cache_percent = 0;
5376 } else if (loop == LOOP_FIND_IDEAL) {
5378 * Didn't find a uncached bg, wait on anything we find
5381 loop = LOOP_CACHING_WAIT;
5387 if (loop == LOOP_ALLOC_CHUNK) {
5388 if (allowed_chunk_alloc) {
5389 ret = do_chunk_alloc(trans, root, num_bytes +
5390 2 * 1024 * 1024, data,
5391 CHUNK_ALLOC_LIMITED);
5392 allowed_chunk_alloc = 0;
5394 done_chunk_alloc = 1;
5395 } else if (!done_chunk_alloc &&
5396 space_info->force_alloc ==
5397 CHUNK_ALLOC_NO_FORCE) {
5398 space_info->force_alloc = CHUNK_ALLOC_LIMITED;
5402 * We didn't allocate a chunk, go ahead and drop the
5403 * empty size and loop again.
5405 if (!done_chunk_alloc)
5406 loop = LOOP_NO_EMPTY_SIZE;
5409 if (loop == LOOP_NO_EMPTY_SIZE) {
5415 } else if (!ins->objectid) {
5417 } else if (ins->objectid) {
5424 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5425 int dump_block_groups)
5427 struct btrfs_block_group_cache *cache;
5430 spin_lock(&info->lock);
5431 printk(KERN_INFO "space_info %llu has %llu free, is %sfull\n",
5432 (unsigned long long)info->flags,
5433 (unsigned long long)(info->total_bytes - info->bytes_used -
5434 info->bytes_pinned - info->bytes_reserved -
5435 info->bytes_readonly),
5436 (info->full) ? "" : "not ");
5437 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5438 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5439 (unsigned long long)info->total_bytes,
5440 (unsigned long long)info->bytes_used,
5441 (unsigned long long)info->bytes_pinned,
5442 (unsigned long long)info->bytes_reserved,
5443 (unsigned long long)info->bytes_may_use,
5444 (unsigned long long)info->bytes_readonly);
5445 spin_unlock(&info->lock);
5447 if (!dump_block_groups)
5450 down_read(&info->groups_sem);
5452 list_for_each_entry(cache, &info->block_groups[index], list) {
5453 spin_lock(&cache->lock);
5454 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5455 "%llu pinned %llu reserved\n",
5456 (unsigned long long)cache->key.objectid,
5457 (unsigned long long)cache->key.offset,
5458 (unsigned long long)btrfs_block_group_used(&cache->item),
5459 (unsigned long long)cache->pinned,
5460 (unsigned long long)cache->reserved);
5461 btrfs_dump_free_space(cache, bytes);
5462 spin_unlock(&cache->lock);
5464 if (++index < BTRFS_NR_RAID_TYPES)
5466 up_read(&info->groups_sem);
5469 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5470 struct btrfs_root *root,
5471 u64 num_bytes, u64 min_alloc_size,
5472 u64 empty_size, u64 hint_byte,
5473 u64 search_end, struct btrfs_key *ins,
5477 u64 search_start = 0;
5479 data = btrfs_get_alloc_profile(root, data);
5482 * the only place that sets empty_size is btrfs_realloc_node, which
5483 * is not called recursively on allocations
5485 if (empty_size || root->ref_cows)
5486 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5487 num_bytes + 2 * 1024 * 1024, data,
5488 CHUNK_ALLOC_NO_FORCE);
5490 WARN_ON(num_bytes < root->sectorsize);
5491 ret = find_free_extent(trans, root, num_bytes, empty_size,
5492 search_start, search_end, hint_byte,
5495 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5496 num_bytes = num_bytes >> 1;
5497 num_bytes = num_bytes & ~(root->sectorsize - 1);
5498 num_bytes = max(num_bytes, min_alloc_size);
5499 do_chunk_alloc(trans, root->fs_info->extent_root,
5500 num_bytes, data, CHUNK_ALLOC_FORCE);
5503 if (ret == -ENOSPC && btrfs_test_opt(root, ENOSPC_DEBUG)) {
5504 struct btrfs_space_info *sinfo;
5506 sinfo = __find_space_info(root->fs_info, data);
5507 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5508 "wanted %llu\n", (unsigned long long)data,
5509 (unsigned long long)num_bytes);
5510 dump_space_info(sinfo, num_bytes, 1);
5513 trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
5518 static int __btrfs_free_reserved_extent(struct btrfs_root *root,
5519 u64 start, u64 len, int pin)
5521 struct btrfs_block_group_cache *cache;
5524 cache = btrfs_lookup_block_group(root->fs_info, start);
5526 printk(KERN_ERR "Unable to find block group for %llu\n",
5527 (unsigned long long)start);
5531 if (btrfs_test_opt(root, DISCARD))
5532 ret = btrfs_discard_extent(root, start, len, NULL);
5535 pin_down_extent(root, cache, start, len, 1);
5537 btrfs_add_free_space(cache, start, len);
5538 btrfs_update_reserved_bytes(cache, len, RESERVE_FREE);
5540 btrfs_put_block_group(cache);
5542 trace_btrfs_reserved_extent_free(root, start, len);
5547 int btrfs_free_reserved_extent(struct btrfs_root *root,
5550 return __btrfs_free_reserved_extent(root, start, len, 0);
5553 int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
5556 return __btrfs_free_reserved_extent(root, start, len, 1);
5559 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5560 struct btrfs_root *root,
5561 u64 parent, u64 root_objectid,
5562 u64 flags, u64 owner, u64 offset,
5563 struct btrfs_key *ins, int ref_mod)
5566 struct btrfs_fs_info *fs_info = root->fs_info;
5567 struct btrfs_extent_item *extent_item;
5568 struct btrfs_extent_inline_ref *iref;
5569 struct btrfs_path *path;
5570 struct extent_buffer *leaf;
5575 type = BTRFS_SHARED_DATA_REF_KEY;
5577 type = BTRFS_EXTENT_DATA_REF_KEY;
5579 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5581 path = btrfs_alloc_path();
5585 path->leave_spinning = 1;
5586 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5590 leaf = path->nodes[0];
5591 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5592 struct btrfs_extent_item);
5593 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5594 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5595 btrfs_set_extent_flags(leaf, extent_item,
5596 flags | BTRFS_EXTENT_FLAG_DATA);
5598 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5599 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5601 struct btrfs_shared_data_ref *ref;
5602 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5603 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5604 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5606 struct btrfs_extent_data_ref *ref;
5607 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5608 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5609 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5610 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5611 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5614 btrfs_mark_buffer_dirty(path->nodes[0]);
5615 btrfs_free_path(path);
5617 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5619 printk(KERN_ERR "btrfs update block group failed for %llu "
5620 "%llu\n", (unsigned long long)ins->objectid,
5621 (unsigned long long)ins->offset);
5627 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5628 struct btrfs_root *root,
5629 u64 parent, u64 root_objectid,
5630 u64 flags, struct btrfs_disk_key *key,
5631 int level, struct btrfs_key *ins)
5634 struct btrfs_fs_info *fs_info = root->fs_info;
5635 struct btrfs_extent_item *extent_item;
5636 struct btrfs_tree_block_info *block_info;
5637 struct btrfs_extent_inline_ref *iref;
5638 struct btrfs_path *path;
5639 struct extent_buffer *leaf;
5640 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5642 path = btrfs_alloc_path();
5646 path->leave_spinning = 1;
5647 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5651 leaf = path->nodes[0];
5652 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5653 struct btrfs_extent_item);
5654 btrfs_set_extent_refs(leaf, extent_item, 1);
5655 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5656 btrfs_set_extent_flags(leaf, extent_item,
5657 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5658 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5660 btrfs_set_tree_block_key(leaf, block_info, key);
5661 btrfs_set_tree_block_level(leaf, block_info, level);
5663 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5665 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5666 btrfs_set_extent_inline_ref_type(leaf, iref,
5667 BTRFS_SHARED_BLOCK_REF_KEY);
5668 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5670 btrfs_set_extent_inline_ref_type(leaf, iref,
5671 BTRFS_TREE_BLOCK_REF_KEY);
5672 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5675 btrfs_mark_buffer_dirty(leaf);
5676 btrfs_free_path(path);
5678 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5680 printk(KERN_ERR "btrfs update block group failed for %llu "
5681 "%llu\n", (unsigned long long)ins->objectid,
5682 (unsigned long long)ins->offset);
5688 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5689 struct btrfs_root *root,
5690 u64 root_objectid, u64 owner,
5691 u64 offset, struct btrfs_key *ins)
5695 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5697 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5698 0, root_objectid, owner, offset,
5699 BTRFS_ADD_DELAYED_EXTENT, NULL);
5704 * this is used by the tree logging recovery code. It records that
5705 * an extent has been allocated and makes sure to clear the free
5706 * space cache bits as well
5708 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5709 struct btrfs_root *root,
5710 u64 root_objectid, u64 owner, u64 offset,
5711 struct btrfs_key *ins)
5714 struct btrfs_block_group_cache *block_group;
5715 struct btrfs_caching_control *caching_ctl;
5716 u64 start = ins->objectid;
5717 u64 num_bytes = ins->offset;
5719 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5720 cache_block_group(block_group, trans, NULL, 0);
5721 caching_ctl = get_caching_control(block_group);
5724 BUG_ON(!block_group_cache_done(block_group));
5725 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5728 mutex_lock(&caching_ctl->mutex);
5730 if (start >= caching_ctl->progress) {
5731 ret = add_excluded_extent(root, start, num_bytes);
5733 } else if (start + num_bytes <= caching_ctl->progress) {
5734 ret = btrfs_remove_free_space(block_group,
5738 num_bytes = caching_ctl->progress - start;
5739 ret = btrfs_remove_free_space(block_group,
5743 start = caching_ctl->progress;
5744 num_bytes = ins->objectid + ins->offset -
5745 caching_ctl->progress;
5746 ret = add_excluded_extent(root, start, num_bytes);
5750 mutex_unlock(&caching_ctl->mutex);
5751 put_caching_control(caching_ctl);
5754 ret = btrfs_update_reserved_bytes(block_group, ins->offset,
5755 RESERVE_ALLOC_NO_ACCOUNT);
5757 btrfs_put_block_group(block_group);
5758 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5759 0, owner, offset, ins, 1);
5763 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5764 struct btrfs_root *root,
5765 u64 bytenr, u32 blocksize,
5768 struct extent_buffer *buf;
5770 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5772 return ERR_PTR(-ENOMEM);
5773 btrfs_set_header_generation(buf, trans->transid);
5774 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
5775 btrfs_tree_lock(buf);
5776 clean_tree_block(trans, root, buf);
5778 btrfs_set_lock_blocking(buf);
5779 btrfs_set_buffer_uptodate(buf);
5781 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5783 * we allow two log transactions at a time, use different
5784 * EXENT bit to differentiate dirty pages.
5786 if (root->log_transid % 2 == 0)
5787 set_extent_dirty(&root->dirty_log_pages, buf->start,
5788 buf->start + buf->len - 1, GFP_NOFS);
5790 set_extent_new(&root->dirty_log_pages, buf->start,
5791 buf->start + buf->len - 1, GFP_NOFS);
5793 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5794 buf->start + buf->len - 1, GFP_NOFS);
5796 trans->blocks_used++;
5797 /* this returns a buffer locked for blocking */
5801 static struct btrfs_block_rsv *
5802 use_block_rsv(struct btrfs_trans_handle *trans,
5803 struct btrfs_root *root, u32 blocksize)
5805 struct btrfs_block_rsv *block_rsv;
5806 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
5809 block_rsv = get_block_rsv(trans, root);
5811 if (block_rsv->size == 0) {
5812 ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
5814 * If we couldn't reserve metadata bytes try and use some from
5815 * the global reserve.
5817 if (ret && block_rsv != global_rsv) {
5818 ret = block_rsv_use_bytes(global_rsv, blocksize);
5821 return ERR_PTR(ret);
5823 return ERR_PTR(ret);
5828 ret = block_rsv_use_bytes(block_rsv, blocksize);
5832 static DEFINE_RATELIMIT_STATE(_rs,
5833 DEFAULT_RATELIMIT_INTERVAL,
5834 /*DEFAULT_RATELIMIT_BURST*/ 2);
5835 if (__ratelimit(&_rs)) {
5836 printk(KERN_DEBUG "btrfs: block rsv returned %d\n", ret);
5839 ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
5842 } else if (ret && block_rsv != global_rsv) {
5843 ret = block_rsv_use_bytes(global_rsv, blocksize);
5849 return ERR_PTR(-ENOSPC);
5852 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5854 block_rsv_add_bytes(block_rsv, blocksize, 0);
5855 block_rsv_release_bytes(block_rsv, NULL, 0);
5859 * finds a free extent and does all the dirty work required for allocation
5860 * returns the key for the extent through ins, and a tree buffer for
5861 * the first block of the extent through buf.
5863 * returns the tree buffer or NULL.
5865 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5866 struct btrfs_root *root, u32 blocksize,
5867 u64 parent, u64 root_objectid,
5868 struct btrfs_disk_key *key, int level,
5869 u64 hint, u64 empty_size)
5871 struct btrfs_key ins;
5872 struct btrfs_block_rsv *block_rsv;
5873 struct extent_buffer *buf;
5878 block_rsv = use_block_rsv(trans, root, blocksize);
5879 if (IS_ERR(block_rsv))
5880 return ERR_CAST(block_rsv);
5882 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5883 empty_size, hint, (u64)-1, &ins, 0);
5885 unuse_block_rsv(block_rsv, blocksize);
5886 return ERR_PTR(ret);
5889 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5891 BUG_ON(IS_ERR(buf));
5893 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5895 parent = ins.objectid;
5896 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5900 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5901 struct btrfs_delayed_extent_op *extent_op;
5902 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5905 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5907 memset(&extent_op->key, 0, sizeof(extent_op->key));
5908 extent_op->flags_to_set = flags;
5909 extent_op->update_key = 1;
5910 extent_op->update_flags = 1;
5911 extent_op->is_data = 0;
5913 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5914 ins.offset, parent, root_objectid,
5915 level, BTRFS_ADD_DELAYED_EXTENT,
5922 struct walk_control {
5923 u64 refs[BTRFS_MAX_LEVEL];
5924 u64 flags[BTRFS_MAX_LEVEL];
5925 struct btrfs_key update_progress;
5935 #define DROP_REFERENCE 1
5936 #define UPDATE_BACKREF 2
5938 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5939 struct btrfs_root *root,
5940 struct walk_control *wc,
5941 struct btrfs_path *path)
5949 struct btrfs_key key;
5950 struct extent_buffer *eb;
5955 if (path->slots[wc->level] < wc->reada_slot) {
5956 wc->reada_count = wc->reada_count * 2 / 3;
5957 wc->reada_count = max(wc->reada_count, 2);
5959 wc->reada_count = wc->reada_count * 3 / 2;
5960 wc->reada_count = min_t(int, wc->reada_count,
5961 BTRFS_NODEPTRS_PER_BLOCK(root));
5964 eb = path->nodes[wc->level];
5965 nritems = btrfs_header_nritems(eb);
5966 blocksize = btrfs_level_size(root, wc->level - 1);
5968 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5969 if (nread >= wc->reada_count)
5973 bytenr = btrfs_node_blockptr(eb, slot);
5974 generation = btrfs_node_ptr_generation(eb, slot);
5976 if (slot == path->slots[wc->level])
5979 if (wc->stage == UPDATE_BACKREF &&
5980 generation <= root->root_key.offset)
5983 /* We don't lock the tree block, it's OK to be racy here */
5984 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5989 if (wc->stage == DROP_REFERENCE) {
5993 if (wc->level == 1 &&
5994 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5996 if (!wc->update_ref ||
5997 generation <= root->root_key.offset)
5999 btrfs_node_key_to_cpu(eb, &key, slot);
6000 ret = btrfs_comp_cpu_keys(&key,
6001 &wc->update_progress);
6005 if (wc->level == 1 &&
6006 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6010 ret = readahead_tree_block(root, bytenr, blocksize,
6016 wc->reada_slot = slot;
6020 * hepler to process tree block while walking down the tree.
6022 * when wc->stage == UPDATE_BACKREF, this function updates
6023 * back refs for pointers in the block.
6025 * NOTE: return value 1 means we should stop walking down.
6027 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
6028 struct btrfs_root *root,
6029 struct btrfs_path *path,
6030 struct walk_control *wc, int lookup_info)
6032 int level = wc->level;
6033 struct extent_buffer *eb = path->nodes[level];
6034 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6037 if (wc->stage == UPDATE_BACKREF &&
6038 btrfs_header_owner(eb) != root->root_key.objectid)
6042 * when reference count of tree block is 1, it won't increase
6043 * again. once full backref flag is set, we never clear it.
6046 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
6047 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
6048 BUG_ON(!path->locks[level]);
6049 ret = btrfs_lookup_extent_info(trans, root,
6054 BUG_ON(wc->refs[level] == 0);
6057 if (wc->stage == DROP_REFERENCE) {
6058 if (wc->refs[level] > 1)
6061 if (path->locks[level] && !wc->keep_locks) {
6062 btrfs_tree_unlock_rw(eb, path->locks[level]);
6063 path->locks[level] = 0;
6068 /* wc->stage == UPDATE_BACKREF */
6069 if (!(wc->flags[level] & flag)) {
6070 BUG_ON(!path->locks[level]);
6071 ret = btrfs_inc_ref(trans, root, eb, 1);
6073 ret = btrfs_dec_ref(trans, root, eb, 0);
6075 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
6078 wc->flags[level] |= flag;
6082 * the block is shared by multiple trees, so it's not good to
6083 * keep the tree lock
6085 if (path->locks[level] && level > 0) {
6086 btrfs_tree_unlock_rw(eb, path->locks[level]);
6087 path->locks[level] = 0;
6093 * hepler to process tree block pointer.
6095 * when wc->stage == DROP_REFERENCE, this function checks
6096 * reference count of the block pointed to. if the block
6097 * is shared and we need update back refs for the subtree
6098 * rooted at the block, this function changes wc->stage to
6099 * UPDATE_BACKREF. if the block is shared and there is no
6100 * need to update back, this function drops the reference
6103 * NOTE: return value 1 means we should stop walking down.
6105 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
6106 struct btrfs_root *root,
6107 struct btrfs_path *path,
6108 struct walk_control *wc, int *lookup_info)
6114 struct btrfs_key key;
6115 struct extent_buffer *next;
6116 int level = wc->level;
6120 generation = btrfs_node_ptr_generation(path->nodes[level],
6121 path->slots[level]);
6123 * if the lower level block was created before the snapshot
6124 * was created, we know there is no need to update back refs
6127 if (wc->stage == UPDATE_BACKREF &&
6128 generation <= root->root_key.offset) {
6133 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
6134 blocksize = btrfs_level_size(root, level - 1);
6136 next = btrfs_find_tree_block(root, bytenr, blocksize);
6138 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
6143 btrfs_tree_lock(next);
6144 btrfs_set_lock_blocking(next);
6146 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6147 &wc->refs[level - 1],
6148 &wc->flags[level - 1]);
6150 BUG_ON(wc->refs[level - 1] == 0);
6153 if (wc->stage == DROP_REFERENCE) {
6154 if (wc->refs[level - 1] > 1) {
6156 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6159 if (!wc->update_ref ||
6160 generation <= root->root_key.offset)
6163 btrfs_node_key_to_cpu(path->nodes[level], &key,
6164 path->slots[level]);
6165 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
6169 wc->stage = UPDATE_BACKREF;
6170 wc->shared_level = level - 1;
6174 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6178 if (!btrfs_buffer_uptodate(next, generation)) {
6179 btrfs_tree_unlock(next);
6180 free_extent_buffer(next);
6186 if (reada && level == 1)
6187 reada_walk_down(trans, root, wc, path);
6188 next = read_tree_block(root, bytenr, blocksize, generation);
6191 btrfs_tree_lock(next);
6192 btrfs_set_lock_blocking(next);
6196 BUG_ON(level != btrfs_header_level(next));
6197 path->nodes[level] = next;
6198 path->slots[level] = 0;
6199 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6205 wc->refs[level - 1] = 0;
6206 wc->flags[level - 1] = 0;
6207 if (wc->stage == DROP_REFERENCE) {
6208 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6209 parent = path->nodes[level]->start;
6211 BUG_ON(root->root_key.objectid !=
6212 btrfs_header_owner(path->nodes[level]));
6216 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
6217 root->root_key.objectid, level - 1, 0);
6220 btrfs_tree_unlock(next);
6221 free_extent_buffer(next);
6227 * hepler to process tree block while walking up the tree.
6229 * when wc->stage == DROP_REFERENCE, this function drops
6230 * reference count on the block.
6232 * when wc->stage == UPDATE_BACKREF, this function changes
6233 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6234 * to UPDATE_BACKREF previously while processing the block.
6236 * NOTE: return value 1 means we should stop walking up.
6238 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6239 struct btrfs_root *root,
6240 struct btrfs_path *path,
6241 struct walk_control *wc)
6244 int level = wc->level;
6245 struct extent_buffer *eb = path->nodes[level];
6248 if (wc->stage == UPDATE_BACKREF) {
6249 BUG_ON(wc->shared_level < level);
6250 if (level < wc->shared_level)
6253 ret = find_next_key(path, level + 1, &wc->update_progress);
6257 wc->stage = DROP_REFERENCE;
6258 wc->shared_level = -1;
6259 path->slots[level] = 0;
6262 * check reference count again if the block isn't locked.
6263 * we should start walking down the tree again if reference
6266 if (!path->locks[level]) {
6268 btrfs_tree_lock(eb);
6269 btrfs_set_lock_blocking(eb);
6270 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6272 ret = btrfs_lookup_extent_info(trans, root,
6277 BUG_ON(wc->refs[level] == 0);
6278 if (wc->refs[level] == 1) {
6279 btrfs_tree_unlock_rw(eb, path->locks[level]);
6285 /* wc->stage == DROP_REFERENCE */
6286 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6288 if (wc->refs[level] == 1) {
6290 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6291 ret = btrfs_dec_ref(trans, root, eb, 1);
6293 ret = btrfs_dec_ref(trans, root, eb, 0);
6296 /* make block locked assertion in clean_tree_block happy */
6297 if (!path->locks[level] &&
6298 btrfs_header_generation(eb) == trans->transid) {
6299 btrfs_tree_lock(eb);
6300 btrfs_set_lock_blocking(eb);
6301 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6303 clean_tree_block(trans, root, eb);
6306 if (eb == root->node) {
6307 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6310 BUG_ON(root->root_key.objectid !=
6311 btrfs_header_owner(eb));
6313 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6314 parent = path->nodes[level + 1]->start;
6316 BUG_ON(root->root_key.objectid !=
6317 btrfs_header_owner(path->nodes[level + 1]));
6320 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6322 wc->refs[level] = 0;
6323 wc->flags[level] = 0;
6327 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6328 struct btrfs_root *root,
6329 struct btrfs_path *path,
6330 struct walk_control *wc)
6332 int level = wc->level;
6333 int lookup_info = 1;
6336 while (level >= 0) {
6337 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6344 if (path->slots[level] >=
6345 btrfs_header_nritems(path->nodes[level]))
6348 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6350 path->slots[level]++;
6359 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6360 struct btrfs_root *root,
6361 struct btrfs_path *path,
6362 struct walk_control *wc, int max_level)
6364 int level = wc->level;
6367 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6368 while (level < max_level && path->nodes[level]) {
6370 if (path->slots[level] + 1 <
6371 btrfs_header_nritems(path->nodes[level])) {
6372 path->slots[level]++;
6375 ret = walk_up_proc(trans, root, path, wc);
6379 if (path->locks[level]) {
6380 btrfs_tree_unlock_rw(path->nodes[level],
6381 path->locks[level]);
6382 path->locks[level] = 0;
6384 free_extent_buffer(path->nodes[level]);
6385 path->nodes[level] = NULL;
6393 * drop a subvolume tree.
6395 * this function traverses the tree freeing any blocks that only
6396 * referenced by the tree.
6398 * when a shared tree block is found. this function decreases its
6399 * reference count by one. if update_ref is true, this function
6400 * also make sure backrefs for the shared block and all lower level
6401 * blocks are properly updated.
6403 void btrfs_drop_snapshot(struct btrfs_root *root,
6404 struct btrfs_block_rsv *block_rsv, int update_ref)
6406 struct btrfs_path *path;
6407 struct btrfs_trans_handle *trans;
6408 struct btrfs_root *tree_root = root->fs_info->tree_root;
6409 struct btrfs_root_item *root_item = &root->root_item;
6410 struct walk_control *wc;
6411 struct btrfs_key key;
6416 path = btrfs_alloc_path();
6422 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6424 btrfs_free_path(path);
6429 trans = btrfs_start_transaction(tree_root, 0);
6430 BUG_ON(IS_ERR(trans));
6433 trans->block_rsv = block_rsv;
6435 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6436 level = btrfs_header_level(root->node);
6437 path->nodes[level] = btrfs_lock_root_node(root);
6438 btrfs_set_lock_blocking(path->nodes[level]);
6439 path->slots[level] = 0;
6440 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6441 memset(&wc->update_progress, 0,
6442 sizeof(wc->update_progress));
6444 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6445 memcpy(&wc->update_progress, &key,
6446 sizeof(wc->update_progress));
6448 level = root_item->drop_level;
6450 path->lowest_level = level;
6451 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6452 path->lowest_level = 0;
6460 * unlock our path, this is safe because only this
6461 * function is allowed to delete this snapshot
6463 btrfs_unlock_up_safe(path, 0);
6465 level = btrfs_header_level(root->node);
6467 btrfs_tree_lock(path->nodes[level]);
6468 btrfs_set_lock_blocking(path->nodes[level]);
6470 ret = btrfs_lookup_extent_info(trans, root,
6471 path->nodes[level]->start,
6472 path->nodes[level]->len,
6476 BUG_ON(wc->refs[level] == 0);
6478 if (level == root_item->drop_level)
6481 btrfs_tree_unlock(path->nodes[level]);
6482 WARN_ON(wc->refs[level] != 1);
6488 wc->shared_level = -1;
6489 wc->stage = DROP_REFERENCE;
6490 wc->update_ref = update_ref;
6492 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6495 ret = walk_down_tree(trans, root, path, wc);
6501 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6508 BUG_ON(wc->stage != DROP_REFERENCE);
6512 if (wc->stage == DROP_REFERENCE) {
6514 btrfs_node_key(path->nodes[level],
6515 &root_item->drop_progress,
6516 path->slots[level]);
6517 root_item->drop_level = level;
6520 BUG_ON(wc->level == 0);
6521 if (btrfs_should_end_transaction(trans, tree_root)) {
6522 ret = btrfs_update_root(trans, tree_root,
6527 btrfs_end_transaction_throttle(trans, tree_root);
6528 trans = btrfs_start_transaction(tree_root, 0);
6529 BUG_ON(IS_ERR(trans));
6531 trans->block_rsv = block_rsv;
6534 btrfs_release_path(path);
6537 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6540 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6541 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6545 /* if we fail to delete the orphan item this time
6546 * around, it'll get picked up the next time.
6548 * The most common failure here is just -ENOENT.
6550 btrfs_del_orphan_item(trans, tree_root,
6551 root->root_key.objectid);
6555 if (root->in_radix) {
6556 btrfs_free_fs_root(tree_root->fs_info, root);
6558 free_extent_buffer(root->node);
6559 free_extent_buffer(root->commit_root);
6563 btrfs_end_transaction_throttle(trans, tree_root);
6565 btrfs_free_path(path);
6568 btrfs_std_error(root->fs_info, err);
6573 * drop subtree rooted at tree block 'node'.
6575 * NOTE: this function will unlock and release tree block 'node'
6577 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6578 struct btrfs_root *root,
6579 struct extent_buffer *node,
6580 struct extent_buffer *parent)
6582 struct btrfs_path *path;
6583 struct walk_control *wc;
6589 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6591 path = btrfs_alloc_path();
6595 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6597 btrfs_free_path(path);
6601 btrfs_assert_tree_locked(parent);
6602 parent_level = btrfs_header_level(parent);
6603 extent_buffer_get(parent);
6604 path->nodes[parent_level] = parent;
6605 path->slots[parent_level] = btrfs_header_nritems(parent);
6607 btrfs_assert_tree_locked(node);
6608 level = btrfs_header_level(node);
6609 path->nodes[level] = node;
6610 path->slots[level] = 0;
6611 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6613 wc->refs[parent_level] = 1;
6614 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6616 wc->shared_level = -1;
6617 wc->stage = DROP_REFERENCE;
6620 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6623 wret = walk_down_tree(trans, root, path, wc);
6629 wret = walk_up_tree(trans, root, path, wc, parent_level);
6637 btrfs_free_path(path);
6641 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
6644 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
6645 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
6648 * we add in the count of missing devices because we want
6649 * to make sure that any RAID levels on a degraded FS
6650 * continue to be honored.
6652 num_devices = root->fs_info->fs_devices->rw_devices +
6653 root->fs_info->fs_devices->missing_devices;
6655 if (num_devices == 1) {
6656 stripped |= BTRFS_BLOCK_GROUP_DUP;
6657 stripped = flags & ~stripped;
6659 /* turn raid0 into single device chunks */
6660 if (flags & BTRFS_BLOCK_GROUP_RAID0)
6663 /* turn mirroring into duplication */
6664 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
6665 BTRFS_BLOCK_GROUP_RAID10))
6666 return stripped | BTRFS_BLOCK_GROUP_DUP;
6669 /* they already had raid on here, just return */
6670 if (flags & stripped)
6673 stripped |= BTRFS_BLOCK_GROUP_DUP;
6674 stripped = flags & ~stripped;
6676 /* switch duplicated blocks with raid1 */
6677 if (flags & BTRFS_BLOCK_GROUP_DUP)
6678 return stripped | BTRFS_BLOCK_GROUP_RAID1;
6680 /* turn single device chunks into raid0 */
6681 return stripped | BTRFS_BLOCK_GROUP_RAID0;
6686 static int set_block_group_ro(struct btrfs_block_group_cache *cache, int force)
6688 struct btrfs_space_info *sinfo = cache->space_info;
6690 u64 min_allocable_bytes;
6695 * We need some metadata space and system metadata space for
6696 * allocating chunks in some corner cases until we force to set
6697 * it to be readonly.
6700 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
6702 min_allocable_bytes = 1 * 1024 * 1024;
6704 min_allocable_bytes = 0;
6706 spin_lock(&sinfo->lock);
6707 spin_lock(&cache->lock);
6714 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
6715 cache->bytes_super - btrfs_block_group_used(&cache->item);
6717 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
6718 sinfo->bytes_may_use + sinfo->bytes_readonly + num_bytes +
6719 min_allocable_bytes <= sinfo->total_bytes) {
6720 sinfo->bytes_readonly += num_bytes;
6725 spin_unlock(&cache->lock);
6726 spin_unlock(&sinfo->lock);
6730 int btrfs_set_block_group_ro(struct btrfs_root *root,
6731 struct btrfs_block_group_cache *cache)
6734 struct btrfs_trans_handle *trans;
6740 trans = btrfs_join_transaction(root);
6741 BUG_ON(IS_ERR(trans));
6743 alloc_flags = update_block_group_flags(root, cache->flags);
6744 if (alloc_flags != cache->flags)
6745 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6748 ret = set_block_group_ro(cache, 0);
6751 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
6752 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6756 ret = set_block_group_ro(cache, 0);
6758 btrfs_end_transaction(trans, root);
6762 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
6763 struct btrfs_root *root, u64 type)
6765 u64 alloc_flags = get_alloc_profile(root, type);
6766 return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6771 * helper to account the unused space of all the readonly block group in the
6772 * list. takes mirrors into account.
6774 static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
6776 struct btrfs_block_group_cache *block_group;
6780 list_for_each_entry(block_group, groups_list, list) {
6781 spin_lock(&block_group->lock);
6783 if (!block_group->ro) {
6784 spin_unlock(&block_group->lock);
6788 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
6789 BTRFS_BLOCK_GROUP_RAID10 |
6790 BTRFS_BLOCK_GROUP_DUP))
6795 free_bytes += (block_group->key.offset -
6796 btrfs_block_group_used(&block_group->item)) *
6799 spin_unlock(&block_group->lock);
6806 * helper to account the unused space of all the readonly block group in the
6807 * space_info. takes mirrors into account.
6809 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
6814 spin_lock(&sinfo->lock);
6816 for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
6817 if (!list_empty(&sinfo->block_groups[i]))
6818 free_bytes += __btrfs_get_ro_block_group_free_space(
6819 &sinfo->block_groups[i]);
6821 spin_unlock(&sinfo->lock);
6826 int btrfs_set_block_group_rw(struct btrfs_root *root,
6827 struct btrfs_block_group_cache *cache)
6829 struct btrfs_space_info *sinfo = cache->space_info;
6834 spin_lock(&sinfo->lock);
6835 spin_lock(&cache->lock);
6836 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
6837 cache->bytes_super - btrfs_block_group_used(&cache->item);
6838 sinfo->bytes_readonly -= num_bytes;
6840 spin_unlock(&cache->lock);
6841 spin_unlock(&sinfo->lock);
6846 * checks to see if its even possible to relocate this block group.
6848 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
6849 * ok to go ahead and try.
6851 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
6853 struct btrfs_block_group_cache *block_group;
6854 struct btrfs_space_info *space_info;
6855 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6856 struct btrfs_device *device;
6864 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
6866 /* odd, couldn't find the block group, leave it alone */
6870 min_free = btrfs_block_group_used(&block_group->item);
6872 /* no bytes used, we're good */
6876 space_info = block_group->space_info;
6877 spin_lock(&space_info->lock);
6879 full = space_info->full;
6882 * if this is the last block group we have in this space, we can't
6883 * relocate it unless we're able to allocate a new chunk below.
6885 * Otherwise, we need to make sure we have room in the space to handle
6886 * all of the extents from this block group. If we can, we're good
6888 if ((space_info->total_bytes != block_group->key.offset) &&
6889 (space_info->bytes_used + space_info->bytes_reserved +
6890 space_info->bytes_pinned + space_info->bytes_readonly +
6891 min_free < space_info->total_bytes)) {
6892 spin_unlock(&space_info->lock);
6895 spin_unlock(&space_info->lock);
6898 * ok we don't have enough space, but maybe we have free space on our
6899 * devices to allocate new chunks for relocation, so loop through our
6900 * alloc devices and guess if we have enough space. However, if we
6901 * were marked as full, then we know there aren't enough chunks, and we
6916 index = get_block_group_index(block_group);
6921 } else if (index == 1) {
6923 } else if (index == 2) {
6926 } else if (index == 3) {
6927 dev_min = fs_devices->rw_devices;
6928 do_div(min_free, dev_min);
6931 mutex_lock(&root->fs_info->chunk_mutex);
6932 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
6936 * check to make sure we can actually find a chunk with enough
6937 * space to fit our block group in.
6939 if (device->total_bytes > device->bytes_used + min_free) {
6940 ret = find_free_dev_extent(NULL, device, min_free,
6945 if (dev_nr >= dev_min)
6951 mutex_unlock(&root->fs_info->chunk_mutex);
6953 btrfs_put_block_group(block_group);
6957 static int find_first_block_group(struct btrfs_root *root,
6958 struct btrfs_path *path, struct btrfs_key *key)
6961 struct btrfs_key found_key;
6962 struct extent_buffer *leaf;
6965 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
6970 slot = path->slots[0];
6971 leaf = path->nodes[0];
6972 if (slot >= btrfs_header_nritems(leaf)) {
6973 ret = btrfs_next_leaf(root, path);
6980 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6982 if (found_key.objectid >= key->objectid &&
6983 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
6993 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
6995 struct btrfs_block_group_cache *block_group;
6999 struct inode *inode;
7001 block_group = btrfs_lookup_first_block_group(info, last);
7002 while (block_group) {
7003 spin_lock(&block_group->lock);
7004 if (block_group->iref)
7006 spin_unlock(&block_group->lock);
7007 block_group = next_block_group(info->tree_root,
7017 inode = block_group->inode;
7018 block_group->iref = 0;
7019 block_group->inode = NULL;
7020 spin_unlock(&block_group->lock);
7022 last = block_group->key.objectid + block_group->key.offset;
7023 btrfs_put_block_group(block_group);
7027 int btrfs_free_block_groups(struct btrfs_fs_info *info)
7029 struct btrfs_block_group_cache *block_group;
7030 struct btrfs_space_info *space_info;
7031 struct btrfs_caching_control *caching_ctl;
7034 down_write(&info->extent_commit_sem);
7035 while (!list_empty(&info->caching_block_groups)) {
7036 caching_ctl = list_entry(info->caching_block_groups.next,
7037 struct btrfs_caching_control, list);
7038 list_del(&caching_ctl->list);
7039 put_caching_control(caching_ctl);
7041 up_write(&info->extent_commit_sem);
7043 spin_lock(&info->block_group_cache_lock);
7044 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
7045 block_group = rb_entry(n, struct btrfs_block_group_cache,
7047 rb_erase(&block_group->cache_node,
7048 &info->block_group_cache_tree);
7049 spin_unlock(&info->block_group_cache_lock);
7051 down_write(&block_group->space_info->groups_sem);
7052 list_del(&block_group->list);
7053 up_write(&block_group->space_info->groups_sem);
7055 if (block_group->cached == BTRFS_CACHE_STARTED)
7056 wait_block_group_cache_done(block_group);
7059 * We haven't cached this block group, which means we could
7060 * possibly have excluded extents on this block group.
7062 if (block_group->cached == BTRFS_CACHE_NO)
7063 free_excluded_extents(info->extent_root, block_group);
7065 btrfs_remove_free_space_cache(block_group);
7066 btrfs_put_block_group(block_group);
7068 spin_lock(&info->block_group_cache_lock);
7070 spin_unlock(&info->block_group_cache_lock);
7072 /* now that all the block groups are freed, go through and
7073 * free all the space_info structs. This is only called during
7074 * the final stages of unmount, and so we know nobody is
7075 * using them. We call synchronize_rcu() once before we start,
7076 * just to be on the safe side.
7080 release_global_block_rsv(info);
7082 while(!list_empty(&info->space_info)) {
7083 space_info = list_entry(info->space_info.next,
7084 struct btrfs_space_info,
7086 if (space_info->bytes_pinned > 0 ||
7087 space_info->bytes_reserved > 0 ||
7088 space_info->bytes_may_use > 0) {
7090 dump_space_info(space_info, 0, 0);
7092 list_del(&space_info->list);
7098 static void __link_block_group(struct btrfs_space_info *space_info,
7099 struct btrfs_block_group_cache *cache)
7101 int index = get_block_group_index(cache);
7103 down_write(&space_info->groups_sem);
7104 list_add_tail(&cache->list, &space_info->block_groups[index]);
7105 up_write(&space_info->groups_sem);
7108 int btrfs_read_block_groups(struct btrfs_root *root)
7110 struct btrfs_path *path;
7112 struct btrfs_block_group_cache *cache;
7113 struct btrfs_fs_info *info = root->fs_info;
7114 struct btrfs_space_info *space_info;
7115 struct btrfs_key key;
7116 struct btrfs_key found_key;
7117 struct extent_buffer *leaf;
7121 root = info->extent_root;
7124 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
7125 path = btrfs_alloc_path();
7130 cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
7131 if (btrfs_test_opt(root, SPACE_CACHE) &&
7132 btrfs_super_generation(root->fs_info->super_copy) != cache_gen)
7134 if (btrfs_test_opt(root, CLEAR_CACHE))
7138 ret = find_first_block_group(root, path, &key);
7143 leaf = path->nodes[0];
7144 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
7145 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7150 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7152 if (!cache->free_space_ctl) {
7158 atomic_set(&cache->count, 1);
7159 spin_lock_init(&cache->lock);
7160 cache->fs_info = info;
7161 INIT_LIST_HEAD(&cache->list);
7162 INIT_LIST_HEAD(&cache->cluster_list);
7165 cache->disk_cache_state = BTRFS_DC_CLEAR;
7167 read_extent_buffer(leaf, &cache->item,
7168 btrfs_item_ptr_offset(leaf, path->slots[0]),
7169 sizeof(cache->item));
7170 memcpy(&cache->key, &found_key, sizeof(found_key));
7172 key.objectid = found_key.objectid + found_key.offset;
7173 btrfs_release_path(path);
7174 cache->flags = btrfs_block_group_flags(&cache->item);
7175 cache->sectorsize = root->sectorsize;
7177 btrfs_init_free_space_ctl(cache);
7180 * We need to exclude the super stripes now so that the space
7181 * info has super bytes accounted for, otherwise we'll think
7182 * we have more space than we actually do.
7184 exclude_super_stripes(root, cache);
7187 * check for two cases, either we are full, and therefore
7188 * don't need to bother with the caching work since we won't
7189 * find any space, or we are empty, and we can just add all
7190 * the space in and be done with it. This saves us _alot_ of
7191 * time, particularly in the full case.
7193 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
7194 cache->last_byte_to_unpin = (u64)-1;
7195 cache->cached = BTRFS_CACHE_FINISHED;
7196 free_excluded_extents(root, cache);
7197 } else if (btrfs_block_group_used(&cache->item) == 0) {
7198 cache->last_byte_to_unpin = (u64)-1;
7199 cache->cached = BTRFS_CACHE_FINISHED;
7200 add_new_free_space(cache, root->fs_info,
7202 found_key.objectid +
7204 free_excluded_extents(root, cache);
7207 ret = update_space_info(info, cache->flags, found_key.offset,
7208 btrfs_block_group_used(&cache->item),
7211 cache->space_info = space_info;
7212 spin_lock(&cache->space_info->lock);
7213 cache->space_info->bytes_readonly += cache->bytes_super;
7214 spin_unlock(&cache->space_info->lock);
7216 __link_block_group(space_info, cache);
7218 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7221 set_avail_alloc_bits(root->fs_info, cache->flags);
7222 if (btrfs_chunk_readonly(root, cache->key.objectid))
7223 set_block_group_ro(cache, 1);
7226 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
7227 if (!(get_alloc_profile(root, space_info->flags) &
7228 (BTRFS_BLOCK_GROUP_RAID10 |
7229 BTRFS_BLOCK_GROUP_RAID1 |
7230 BTRFS_BLOCK_GROUP_DUP)))
7233 * avoid allocating from un-mirrored block group if there are
7234 * mirrored block groups.
7236 list_for_each_entry(cache, &space_info->block_groups[3], list)
7237 set_block_group_ro(cache, 1);
7238 list_for_each_entry(cache, &space_info->block_groups[4], list)
7239 set_block_group_ro(cache, 1);
7242 init_global_block_rsv(info);
7245 btrfs_free_path(path);
7249 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7250 struct btrfs_root *root, u64 bytes_used,
7251 u64 type, u64 chunk_objectid, u64 chunk_offset,
7255 struct btrfs_root *extent_root;
7256 struct btrfs_block_group_cache *cache;
7258 extent_root = root->fs_info->extent_root;
7260 root->fs_info->last_trans_log_full_commit = trans->transid;
7262 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7265 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7267 if (!cache->free_space_ctl) {
7272 cache->key.objectid = chunk_offset;
7273 cache->key.offset = size;
7274 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7275 cache->sectorsize = root->sectorsize;
7276 cache->fs_info = root->fs_info;
7278 atomic_set(&cache->count, 1);
7279 spin_lock_init(&cache->lock);
7280 INIT_LIST_HEAD(&cache->list);
7281 INIT_LIST_HEAD(&cache->cluster_list);
7283 btrfs_init_free_space_ctl(cache);
7285 btrfs_set_block_group_used(&cache->item, bytes_used);
7286 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7287 cache->flags = type;
7288 btrfs_set_block_group_flags(&cache->item, type);
7290 cache->last_byte_to_unpin = (u64)-1;
7291 cache->cached = BTRFS_CACHE_FINISHED;
7292 exclude_super_stripes(root, cache);
7294 add_new_free_space(cache, root->fs_info, chunk_offset,
7295 chunk_offset + size);
7297 free_excluded_extents(root, cache);
7299 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7300 &cache->space_info);
7303 spin_lock(&cache->space_info->lock);
7304 cache->space_info->bytes_readonly += cache->bytes_super;
7305 spin_unlock(&cache->space_info->lock);
7307 __link_block_group(cache->space_info, cache);
7309 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7312 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
7313 sizeof(cache->item));
7316 set_avail_alloc_bits(extent_root->fs_info, type);
7321 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7322 struct btrfs_root *root, u64 group_start)
7324 struct btrfs_path *path;
7325 struct btrfs_block_group_cache *block_group;
7326 struct btrfs_free_cluster *cluster;
7327 struct btrfs_root *tree_root = root->fs_info->tree_root;
7328 struct btrfs_key key;
7329 struct inode *inode;
7333 root = root->fs_info->extent_root;
7335 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7336 BUG_ON(!block_group);
7337 BUG_ON(!block_group->ro);
7340 * Free the reserved super bytes from this block group before
7343 free_excluded_extents(root, block_group);
7345 memcpy(&key, &block_group->key, sizeof(key));
7346 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
7347 BTRFS_BLOCK_GROUP_RAID1 |
7348 BTRFS_BLOCK_GROUP_RAID10))
7353 /* make sure this block group isn't part of an allocation cluster */
7354 cluster = &root->fs_info->data_alloc_cluster;
7355 spin_lock(&cluster->refill_lock);
7356 btrfs_return_cluster_to_free_space(block_group, cluster);
7357 spin_unlock(&cluster->refill_lock);
7360 * make sure this block group isn't part of a metadata
7361 * allocation cluster
7363 cluster = &root->fs_info->meta_alloc_cluster;
7364 spin_lock(&cluster->refill_lock);
7365 btrfs_return_cluster_to_free_space(block_group, cluster);
7366 spin_unlock(&cluster->refill_lock);
7368 path = btrfs_alloc_path();
7374 inode = lookup_free_space_inode(tree_root, block_group, path);
7375 if (!IS_ERR(inode)) {
7376 ret = btrfs_orphan_add(trans, inode);
7379 /* One for the block groups ref */
7380 spin_lock(&block_group->lock);
7381 if (block_group->iref) {
7382 block_group->iref = 0;
7383 block_group->inode = NULL;
7384 spin_unlock(&block_group->lock);
7387 spin_unlock(&block_group->lock);
7389 /* One for our lookup ref */
7390 btrfs_add_delayed_iput(inode);
7393 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
7394 key.offset = block_group->key.objectid;
7397 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
7401 btrfs_release_path(path);
7403 ret = btrfs_del_item(trans, tree_root, path);
7406 btrfs_release_path(path);
7409 spin_lock(&root->fs_info->block_group_cache_lock);
7410 rb_erase(&block_group->cache_node,
7411 &root->fs_info->block_group_cache_tree);
7412 spin_unlock(&root->fs_info->block_group_cache_lock);
7414 down_write(&block_group->space_info->groups_sem);
7416 * we must use list_del_init so people can check to see if they
7417 * are still on the list after taking the semaphore
7419 list_del_init(&block_group->list);
7420 up_write(&block_group->space_info->groups_sem);
7422 if (block_group->cached == BTRFS_CACHE_STARTED)
7423 wait_block_group_cache_done(block_group);
7425 btrfs_remove_free_space_cache(block_group);
7427 spin_lock(&block_group->space_info->lock);
7428 block_group->space_info->total_bytes -= block_group->key.offset;
7429 block_group->space_info->bytes_readonly -= block_group->key.offset;
7430 block_group->space_info->disk_total -= block_group->key.offset * factor;
7431 spin_unlock(&block_group->space_info->lock);
7433 memcpy(&key, &block_group->key, sizeof(key));
7435 btrfs_clear_space_info_full(root->fs_info);
7437 btrfs_put_block_group(block_group);
7438 btrfs_put_block_group(block_group);
7440 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
7446 ret = btrfs_del_item(trans, root, path);
7448 btrfs_free_path(path);
7452 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
7454 struct btrfs_space_info *space_info;
7455 struct btrfs_super_block *disk_super;
7461 disk_super = fs_info->super_copy;
7462 if (!btrfs_super_root(disk_super))
7465 features = btrfs_super_incompat_flags(disk_super);
7466 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
7469 flags = BTRFS_BLOCK_GROUP_SYSTEM;
7470 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7475 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
7476 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7478 flags = BTRFS_BLOCK_GROUP_METADATA;
7479 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7483 flags = BTRFS_BLOCK_GROUP_DATA;
7484 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7490 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
7492 return unpin_extent_range(root, start, end);
7495 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
7496 u64 num_bytes, u64 *actual_bytes)
7498 return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
7501 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
7503 struct btrfs_fs_info *fs_info = root->fs_info;
7504 struct btrfs_block_group_cache *cache = NULL;
7511 cache = btrfs_lookup_block_group(fs_info, range->start);
7514 if (cache->key.objectid >= (range->start + range->len)) {
7515 btrfs_put_block_group(cache);
7519 start = max(range->start, cache->key.objectid);
7520 end = min(range->start + range->len,
7521 cache->key.objectid + cache->key.offset);
7523 if (end - start >= range->minlen) {
7524 if (!block_group_cache_done(cache)) {
7525 ret = cache_block_group(cache, NULL, root, 0);
7527 wait_block_group_cache_done(cache);
7529 ret = btrfs_trim_block_group(cache,
7535 trimmed += group_trimmed;
7537 btrfs_put_block_group(cache);
7542 cache = next_block_group(fs_info->tree_root, cache);
7545 range->len = trimmed;