2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
18 #include <linux/sched.h>
19 #include <linux/pagemap.h>
20 #include <linux/writeback.h>
21 #include <linux/blkdev.h>
22 #include <linux/sort.h>
23 #include <linux/rcupdate.h>
24 #include <linux/kthread.h>
25 #include <linux/slab.h>
30 #include "print-tree.h"
31 #include "transaction.h"
34 #include "free-space-cache.h"
36 static int update_block_group(struct btrfs_trans_handle *trans,
37 struct btrfs_root *root,
38 u64 bytenr, u64 num_bytes, int alloc);
39 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
40 u64 num_bytes, int reserve, int sinfo);
41 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
42 struct btrfs_root *root,
43 u64 bytenr, u64 num_bytes, u64 parent,
44 u64 root_objectid, u64 owner_objectid,
45 u64 owner_offset, int refs_to_drop,
46 struct btrfs_delayed_extent_op *extra_op);
47 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
48 struct extent_buffer *leaf,
49 struct btrfs_extent_item *ei);
50 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
51 struct btrfs_root *root,
52 u64 parent, u64 root_objectid,
53 u64 flags, u64 owner, u64 offset,
54 struct btrfs_key *ins, int ref_mod);
55 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
56 struct btrfs_root *root,
57 u64 parent, u64 root_objectid,
58 u64 flags, struct btrfs_disk_key *key,
59 int level, struct btrfs_key *ins);
60 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
61 struct btrfs_root *extent_root, u64 alloc_bytes,
62 u64 flags, int force);
63 static int find_next_key(struct btrfs_path *path, int level,
64 struct btrfs_key *key);
65 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
66 int dump_block_groups);
69 block_group_cache_done(struct btrfs_block_group_cache *cache)
72 return cache->cached == BTRFS_CACHE_FINISHED;
75 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
77 return (cache->flags & bits) == bits;
80 void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
82 atomic_inc(&cache->count);
85 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
87 if (atomic_dec_and_test(&cache->count)) {
88 WARN_ON(cache->pinned > 0);
89 WARN_ON(cache->reserved > 0);
90 WARN_ON(cache->reserved_pinned > 0);
96 * this adds the block group to the fs_info rb tree for the block group
99 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
100 struct btrfs_block_group_cache *block_group)
103 struct rb_node *parent = NULL;
104 struct btrfs_block_group_cache *cache;
106 spin_lock(&info->block_group_cache_lock);
107 p = &info->block_group_cache_tree.rb_node;
111 cache = rb_entry(parent, struct btrfs_block_group_cache,
113 if (block_group->key.objectid < cache->key.objectid) {
115 } else if (block_group->key.objectid > cache->key.objectid) {
118 spin_unlock(&info->block_group_cache_lock);
123 rb_link_node(&block_group->cache_node, parent, p);
124 rb_insert_color(&block_group->cache_node,
125 &info->block_group_cache_tree);
126 spin_unlock(&info->block_group_cache_lock);
132 * This will return the block group at or after bytenr if contains is 0, else
133 * it will return the block group that contains the bytenr
135 static struct btrfs_block_group_cache *
136 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
139 struct btrfs_block_group_cache *cache, *ret = NULL;
143 spin_lock(&info->block_group_cache_lock);
144 n = info->block_group_cache_tree.rb_node;
147 cache = rb_entry(n, struct btrfs_block_group_cache,
149 end = cache->key.objectid + cache->key.offset - 1;
150 start = cache->key.objectid;
152 if (bytenr < start) {
153 if (!contains && (!ret || start < ret->key.objectid))
156 } else if (bytenr > start) {
157 if (contains && bytenr <= end) {
168 btrfs_get_block_group(ret);
169 spin_unlock(&info->block_group_cache_lock);
174 static int add_excluded_extent(struct btrfs_root *root,
175 u64 start, u64 num_bytes)
177 u64 end = start + num_bytes - 1;
178 set_extent_bits(&root->fs_info->freed_extents[0],
179 start, end, EXTENT_UPTODATE, GFP_NOFS);
180 set_extent_bits(&root->fs_info->freed_extents[1],
181 start, end, EXTENT_UPTODATE, GFP_NOFS);
185 static void free_excluded_extents(struct btrfs_root *root,
186 struct btrfs_block_group_cache *cache)
190 start = cache->key.objectid;
191 end = start + cache->key.offset - 1;
193 clear_extent_bits(&root->fs_info->freed_extents[0],
194 start, end, EXTENT_UPTODATE, GFP_NOFS);
195 clear_extent_bits(&root->fs_info->freed_extents[1],
196 start, end, EXTENT_UPTODATE, GFP_NOFS);
199 static int exclude_super_stripes(struct btrfs_root *root,
200 struct btrfs_block_group_cache *cache)
207 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
208 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
209 cache->bytes_super += stripe_len;
210 ret = add_excluded_extent(root, cache->key.objectid,
215 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
216 bytenr = btrfs_sb_offset(i);
217 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
218 cache->key.objectid, bytenr,
219 0, &logical, &nr, &stripe_len);
223 cache->bytes_super += stripe_len;
224 ret = add_excluded_extent(root, logical[nr],
234 static struct btrfs_caching_control *
235 get_caching_control(struct btrfs_block_group_cache *cache)
237 struct btrfs_caching_control *ctl;
239 spin_lock(&cache->lock);
240 if (cache->cached != BTRFS_CACHE_STARTED) {
241 spin_unlock(&cache->lock);
245 /* We're loading it the fast way, so we don't have a caching_ctl. */
246 if (!cache->caching_ctl) {
247 spin_unlock(&cache->lock);
251 ctl = cache->caching_ctl;
252 atomic_inc(&ctl->count);
253 spin_unlock(&cache->lock);
257 static void put_caching_control(struct btrfs_caching_control *ctl)
259 if (atomic_dec_and_test(&ctl->count))
264 * this is only called by cache_block_group, since we could have freed extents
265 * we need to check the pinned_extents for any extents that can't be used yet
266 * since their free space will be released as soon as the transaction commits.
268 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
269 struct btrfs_fs_info *info, u64 start, u64 end)
271 u64 extent_start, extent_end, size, total_added = 0;
274 while (start < end) {
275 ret = find_first_extent_bit(info->pinned_extents, start,
276 &extent_start, &extent_end,
277 EXTENT_DIRTY | EXTENT_UPTODATE);
281 if (extent_start <= start) {
282 start = extent_end + 1;
283 } else if (extent_start > start && extent_start < end) {
284 size = extent_start - start;
286 ret = btrfs_add_free_space(block_group, start,
289 start = extent_end + 1;
298 ret = btrfs_add_free_space(block_group, start, size);
305 static int caching_kthread(void *data)
307 struct btrfs_block_group_cache *block_group = data;
308 struct btrfs_fs_info *fs_info = block_group->fs_info;
309 struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
310 struct btrfs_root *extent_root = fs_info->extent_root;
311 struct btrfs_path *path;
312 struct extent_buffer *leaf;
313 struct btrfs_key key;
319 path = btrfs_alloc_path();
323 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
326 * We don't want to deadlock with somebody trying to allocate a new
327 * extent for the extent root while also trying to search the extent
328 * root to add free space. So we skip locking and search the commit
329 * root, since its read-only
331 path->skip_locking = 1;
332 path->search_commit_root = 1;
337 key.type = BTRFS_EXTENT_ITEM_KEY;
339 mutex_lock(&caching_ctl->mutex);
340 /* need to make sure the commit_root doesn't disappear */
341 down_read(&fs_info->extent_commit_sem);
343 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
347 leaf = path->nodes[0];
348 nritems = btrfs_header_nritems(leaf);
352 if (fs_info->closing > 1) {
357 if (path->slots[0] < nritems) {
358 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
360 ret = find_next_key(path, 0, &key);
364 caching_ctl->progress = last;
365 btrfs_release_path(extent_root, path);
366 up_read(&fs_info->extent_commit_sem);
367 mutex_unlock(&caching_ctl->mutex);
368 if (btrfs_transaction_in_commit(fs_info))
375 if (key.objectid < block_group->key.objectid) {
380 if (key.objectid >= block_group->key.objectid +
381 block_group->key.offset)
384 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
385 total_found += add_new_free_space(block_group,
388 last = key.objectid + key.offset;
390 if (total_found > (1024 * 1024 * 2)) {
392 wake_up(&caching_ctl->wait);
399 total_found += add_new_free_space(block_group, fs_info, last,
400 block_group->key.objectid +
401 block_group->key.offset);
402 caching_ctl->progress = (u64)-1;
404 spin_lock(&block_group->lock);
405 block_group->caching_ctl = NULL;
406 block_group->cached = BTRFS_CACHE_FINISHED;
407 spin_unlock(&block_group->lock);
410 btrfs_free_path(path);
411 up_read(&fs_info->extent_commit_sem);
413 free_excluded_extents(extent_root, block_group);
415 mutex_unlock(&caching_ctl->mutex);
416 wake_up(&caching_ctl->wait);
418 put_caching_control(caching_ctl);
419 atomic_dec(&block_group->space_info->caching_threads);
420 btrfs_put_block_group(block_group);
425 static int cache_block_group(struct btrfs_block_group_cache *cache,
426 struct btrfs_trans_handle *trans,
427 struct btrfs_root *root,
430 struct btrfs_fs_info *fs_info = cache->fs_info;
431 struct btrfs_caching_control *caching_ctl;
432 struct task_struct *tsk;
436 if (cache->cached != BTRFS_CACHE_NO)
440 * We can't do the read from on-disk cache during a commit since we need
441 * to have the normal tree locking. Also if we are currently trying to
442 * allocate blocks for the tree root we can't do the fast caching since
443 * we likely hold important locks.
445 if (!trans->transaction->in_commit &&
446 (root && root != root->fs_info->tree_root)) {
447 spin_lock(&cache->lock);
448 if (cache->cached != BTRFS_CACHE_NO) {
449 spin_unlock(&cache->lock);
452 cache->cached = BTRFS_CACHE_STARTED;
453 spin_unlock(&cache->lock);
455 ret = load_free_space_cache(fs_info, cache);
457 spin_lock(&cache->lock);
459 cache->cached = BTRFS_CACHE_FINISHED;
460 cache->last_byte_to_unpin = (u64)-1;
462 cache->cached = BTRFS_CACHE_NO;
464 spin_unlock(&cache->lock);
466 free_excluded_extents(fs_info->extent_root, cache);
474 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
475 BUG_ON(!caching_ctl);
477 INIT_LIST_HEAD(&caching_ctl->list);
478 mutex_init(&caching_ctl->mutex);
479 init_waitqueue_head(&caching_ctl->wait);
480 caching_ctl->block_group = cache;
481 caching_ctl->progress = cache->key.objectid;
482 /* one for caching kthread, one for caching block group list */
483 atomic_set(&caching_ctl->count, 2);
485 spin_lock(&cache->lock);
486 if (cache->cached != BTRFS_CACHE_NO) {
487 spin_unlock(&cache->lock);
491 cache->caching_ctl = caching_ctl;
492 cache->cached = BTRFS_CACHE_STARTED;
493 spin_unlock(&cache->lock);
495 down_write(&fs_info->extent_commit_sem);
496 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
497 up_write(&fs_info->extent_commit_sem);
499 atomic_inc(&cache->space_info->caching_threads);
500 btrfs_get_block_group(cache);
502 tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
503 cache->key.objectid);
506 printk(KERN_ERR "error running thread %d\n", ret);
514 * return the block group that starts at or after bytenr
516 static struct btrfs_block_group_cache *
517 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
519 struct btrfs_block_group_cache *cache;
521 cache = block_group_cache_tree_search(info, bytenr, 0);
527 * return the block group that contains the given bytenr
529 struct btrfs_block_group_cache *btrfs_lookup_block_group(
530 struct btrfs_fs_info *info,
533 struct btrfs_block_group_cache *cache;
535 cache = block_group_cache_tree_search(info, bytenr, 1);
540 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
543 struct list_head *head = &info->space_info;
544 struct btrfs_space_info *found;
546 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
547 BTRFS_BLOCK_GROUP_METADATA;
550 list_for_each_entry_rcu(found, head, list) {
551 if (found->flags & flags) {
561 * after adding space to the filesystem, we need to clear the full flags
562 * on all the space infos.
564 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
566 struct list_head *head = &info->space_info;
567 struct btrfs_space_info *found;
570 list_for_each_entry_rcu(found, head, list)
575 static u64 div_factor(u64 num, int factor)
584 static u64 div_factor_fine(u64 num, int factor)
593 u64 btrfs_find_block_group(struct btrfs_root *root,
594 u64 search_start, u64 search_hint, int owner)
596 struct btrfs_block_group_cache *cache;
598 u64 last = max(search_hint, search_start);
605 cache = btrfs_lookup_first_block_group(root->fs_info, last);
609 spin_lock(&cache->lock);
610 last = cache->key.objectid + cache->key.offset;
611 used = btrfs_block_group_used(&cache->item);
613 if ((full_search || !cache->ro) &&
614 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
615 if (used + cache->pinned + cache->reserved <
616 div_factor(cache->key.offset, factor)) {
617 group_start = cache->key.objectid;
618 spin_unlock(&cache->lock);
619 btrfs_put_block_group(cache);
623 spin_unlock(&cache->lock);
624 btrfs_put_block_group(cache);
632 if (!full_search && factor < 10) {
642 /* simple helper to search for an existing extent at a given offset */
643 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
646 struct btrfs_key key;
647 struct btrfs_path *path;
649 path = btrfs_alloc_path();
651 key.objectid = start;
653 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
654 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
656 btrfs_free_path(path);
661 * helper function to lookup reference count and flags of extent.
663 * the head node for delayed ref is used to store the sum of all the
664 * reference count modifications queued up in the rbtree. the head
665 * node may also store the extent flags to set. This way you can check
666 * to see what the reference count and extent flags would be if all of
667 * the delayed refs are not processed.
669 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
670 struct btrfs_root *root, u64 bytenr,
671 u64 num_bytes, u64 *refs, u64 *flags)
673 struct btrfs_delayed_ref_head *head;
674 struct btrfs_delayed_ref_root *delayed_refs;
675 struct btrfs_path *path;
676 struct btrfs_extent_item *ei;
677 struct extent_buffer *leaf;
678 struct btrfs_key key;
684 path = btrfs_alloc_path();
688 key.objectid = bytenr;
689 key.type = BTRFS_EXTENT_ITEM_KEY;
690 key.offset = num_bytes;
692 path->skip_locking = 1;
693 path->search_commit_root = 1;
696 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
702 leaf = path->nodes[0];
703 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
704 if (item_size >= sizeof(*ei)) {
705 ei = btrfs_item_ptr(leaf, path->slots[0],
706 struct btrfs_extent_item);
707 num_refs = btrfs_extent_refs(leaf, ei);
708 extent_flags = btrfs_extent_flags(leaf, ei);
710 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
711 struct btrfs_extent_item_v0 *ei0;
712 BUG_ON(item_size != sizeof(*ei0));
713 ei0 = btrfs_item_ptr(leaf, path->slots[0],
714 struct btrfs_extent_item_v0);
715 num_refs = btrfs_extent_refs_v0(leaf, ei0);
716 /* FIXME: this isn't correct for data */
717 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
722 BUG_ON(num_refs == 0);
732 delayed_refs = &trans->transaction->delayed_refs;
733 spin_lock(&delayed_refs->lock);
734 head = btrfs_find_delayed_ref_head(trans, bytenr);
736 if (!mutex_trylock(&head->mutex)) {
737 atomic_inc(&head->node.refs);
738 spin_unlock(&delayed_refs->lock);
740 btrfs_release_path(root->fs_info->extent_root, path);
742 mutex_lock(&head->mutex);
743 mutex_unlock(&head->mutex);
744 btrfs_put_delayed_ref(&head->node);
747 if (head->extent_op && head->extent_op->update_flags)
748 extent_flags |= head->extent_op->flags_to_set;
750 BUG_ON(num_refs == 0);
752 num_refs += head->node.ref_mod;
753 mutex_unlock(&head->mutex);
755 spin_unlock(&delayed_refs->lock);
757 WARN_ON(num_refs == 0);
761 *flags = extent_flags;
763 btrfs_free_path(path);
768 * Back reference rules. Back refs have three main goals:
770 * 1) differentiate between all holders of references to an extent so that
771 * when a reference is dropped we can make sure it was a valid reference
772 * before freeing the extent.
774 * 2) Provide enough information to quickly find the holders of an extent
775 * if we notice a given block is corrupted or bad.
777 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
778 * maintenance. This is actually the same as #2, but with a slightly
779 * different use case.
781 * There are two kinds of back refs. The implicit back refs is optimized
782 * for pointers in non-shared tree blocks. For a given pointer in a block,
783 * back refs of this kind provide information about the block's owner tree
784 * and the pointer's key. These information allow us to find the block by
785 * b-tree searching. The full back refs is for pointers in tree blocks not
786 * referenced by their owner trees. The location of tree block is recorded
787 * in the back refs. Actually the full back refs is generic, and can be
788 * used in all cases the implicit back refs is used. The major shortcoming
789 * of the full back refs is its overhead. Every time a tree block gets
790 * COWed, we have to update back refs entry for all pointers in it.
792 * For a newly allocated tree block, we use implicit back refs for
793 * pointers in it. This means most tree related operations only involve
794 * implicit back refs. For a tree block created in old transaction, the
795 * only way to drop a reference to it is COW it. So we can detect the
796 * event that tree block loses its owner tree's reference and do the
797 * back refs conversion.
799 * When a tree block is COW'd through a tree, there are four cases:
801 * The reference count of the block is one and the tree is the block's
802 * owner tree. Nothing to do in this case.
804 * The reference count of the block is one and the tree is not the
805 * block's owner tree. In this case, full back refs is used for pointers
806 * in the block. Remove these full back refs, add implicit back refs for
807 * every pointers in the new block.
809 * The reference count of the block is greater than one and the tree is
810 * the block's owner tree. In this case, implicit back refs is used for
811 * pointers in the block. Add full back refs for every pointers in the
812 * block, increase lower level extents' reference counts. The original
813 * implicit back refs are entailed to the new block.
815 * The reference count of the block is greater than one and the tree is
816 * not the block's owner tree. Add implicit back refs for every pointer in
817 * the new block, increase lower level extents' reference count.
819 * Back Reference Key composing:
821 * The key objectid corresponds to the first byte in the extent,
822 * The key type is used to differentiate between types of back refs.
823 * There are different meanings of the key offset for different types
826 * File extents can be referenced by:
828 * - multiple snapshots, subvolumes, or different generations in one subvol
829 * - different files inside a single subvolume
830 * - different offsets inside a file (bookend extents in file.c)
832 * The extent ref structure for the implicit back refs has fields for:
834 * - Objectid of the subvolume root
835 * - objectid of the file holding the reference
836 * - original offset in the file
837 * - how many bookend extents
839 * The key offset for the implicit back refs is hash of the first
842 * The extent ref structure for the full back refs has field for:
844 * - number of pointers in the tree leaf
846 * The key offset for the implicit back refs is the first byte of
849 * When a file extent is allocated, The implicit back refs is used.
850 * the fields are filled in:
852 * (root_key.objectid, inode objectid, offset in file, 1)
854 * When a file extent is removed file truncation, we find the
855 * corresponding implicit back refs and check the following fields:
857 * (btrfs_header_owner(leaf), inode objectid, offset in file)
859 * Btree extents can be referenced by:
861 * - Different subvolumes
863 * Both the implicit back refs and the full back refs for tree blocks
864 * only consist of key. The key offset for the implicit back refs is
865 * objectid of block's owner tree. The key offset for the full back refs
866 * is the first byte of parent block.
868 * When implicit back refs is used, information about the lowest key and
869 * level of the tree block are required. These information are stored in
870 * tree block info structure.
873 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
874 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
875 struct btrfs_root *root,
876 struct btrfs_path *path,
877 u64 owner, u32 extra_size)
879 struct btrfs_extent_item *item;
880 struct btrfs_extent_item_v0 *ei0;
881 struct btrfs_extent_ref_v0 *ref0;
882 struct btrfs_tree_block_info *bi;
883 struct extent_buffer *leaf;
884 struct btrfs_key key;
885 struct btrfs_key found_key;
886 u32 new_size = sizeof(*item);
890 leaf = path->nodes[0];
891 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
893 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
894 ei0 = btrfs_item_ptr(leaf, path->slots[0],
895 struct btrfs_extent_item_v0);
896 refs = btrfs_extent_refs_v0(leaf, ei0);
898 if (owner == (u64)-1) {
900 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
901 ret = btrfs_next_leaf(root, path);
905 leaf = path->nodes[0];
907 btrfs_item_key_to_cpu(leaf, &found_key,
909 BUG_ON(key.objectid != found_key.objectid);
910 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
914 ref0 = btrfs_item_ptr(leaf, path->slots[0],
915 struct btrfs_extent_ref_v0);
916 owner = btrfs_ref_objectid_v0(leaf, ref0);
920 btrfs_release_path(root, path);
922 if (owner < BTRFS_FIRST_FREE_OBJECTID)
923 new_size += sizeof(*bi);
925 new_size -= sizeof(*ei0);
926 ret = btrfs_search_slot(trans, root, &key, path,
927 new_size + extra_size, 1);
932 ret = btrfs_extend_item(trans, root, path, new_size);
935 leaf = path->nodes[0];
936 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
937 btrfs_set_extent_refs(leaf, item, refs);
938 /* FIXME: get real generation */
939 btrfs_set_extent_generation(leaf, item, 0);
940 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
941 btrfs_set_extent_flags(leaf, item,
942 BTRFS_EXTENT_FLAG_TREE_BLOCK |
943 BTRFS_BLOCK_FLAG_FULL_BACKREF);
944 bi = (struct btrfs_tree_block_info *)(item + 1);
945 /* FIXME: get first key of the block */
946 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
947 btrfs_set_tree_block_level(leaf, bi, (int)owner);
949 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
951 btrfs_mark_buffer_dirty(leaf);
956 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
958 u32 high_crc = ~(u32)0;
959 u32 low_crc = ~(u32)0;
962 lenum = cpu_to_le64(root_objectid);
963 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
964 lenum = cpu_to_le64(owner);
965 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
966 lenum = cpu_to_le64(offset);
967 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
969 return ((u64)high_crc << 31) ^ (u64)low_crc;
972 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
973 struct btrfs_extent_data_ref *ref)
975 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
976 btrfs_extent_data_ref_objectid(leaf, ref),
977 btrfs_extent_data_ref_offset(leaf, ref));
980 static int match_extent_data_ref(struct extent_buffer *leaf,
981 struct btrfs_extent_data_ref *ref,
982 u64 root_objectid, u64 owner, u64 offset)
984 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
985 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
986 btrfs_extent_data_ref_offset(leaf, ref) != offset)
991 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
992 struct btrfs_root *root,
993 struct btrfs_path *path,
994 u64 bytenr, u64 parent,
996 u64 owner, u64 offset)
998 struct btrfs_key key;
999 struct btrfs_extent_data_ref *ref;
1000 struct extent_buffer *leaf;
1006 key.objectid = bytenr;
1008 key.type = BTRFS_SHARED_DATA_REF_KEY;
1009 key.offset = parent;
1011 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1012 key.offset = hash_extent_data_ref(root_objectid,
1017 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1026 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1027 key.type = BTRFS_EXTENT_REF_V0_KEY;
1028 btrfs_release_path(root, path);
1029 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1040 leaf = path->nodes[0];
1041 nritems = btrfs_header_nritems(leaf);
1043 if (path->slots[0] >= nritems) {
1044 ret = btrfs_next_leaf(root, path);
1050 leaf = path->nodes[0];
1051 nritems = btrfs_header_nritems(leaf);
1055 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1056 if (key.objectid != bytenr ||
1057 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1060 ref = btrfs_item_ptr(leaf, path->slots[0],
1061 struct btrfs_extent_data_ref);
1063 if (match_extent_data_ref(leaf, ref, root_objectid,
1066 btrfs_release_path(root, path);
1078 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1079 struct btrfs_root *root,
1080 struct btrfs_path *path,
1081 u64 bytenr, u64 parent,
1082 u64 root_objectid, u64 owner,
1083 u64 offset, int refs_to_add)
1085 struct btrfs_key key;
1086 struct extent_buffer *leaf;
1091 key.objectid = bytenr;
1093 key.type = BTRFS_SHARED_DATA_REF_KEY;
1094 key.offset = parent;
1095 size = sizeof(struct btrfs_shared_data_ref);
1097 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1098 key.offset = hash_extent_data_ref(root_objectid,
1100 size = sizeof(struct btrfs_extent_data_ref);
1103 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1104 if (ret && ret != -EEXIST)
1107 leaf = path->nodes[0];
1109 struct btrfs_shared_data_ref *ref;
1110 ref = btrfs_item_ptr(leaf, path->slots[0],
1111 struct btrfs_shared_data_ref);
1113 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1115 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1116 num_refs += refs_to_add;
1117 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1120 struct btrfs_extent_data_ref *ref;
1121 while (ret == -EEXIST) {
1122 ref = btrfs_item_ptr(leaf, path->slots[0],
1123 struct btrfs_extent_data_ref);
1124 if (match_extent_data_ref(leaf, ref, root_objectid,
1127 btrfs_release_path(root, path);
1129 ret = btrfs_insert_empty_item(trans, root, path, &key,
1131 if (ret && ret != -EEXIST)
1134 leaf = path->nodes[0];
1136 ref = btrfs_item_ptr(leaf, path->slots[0],
1137 struct btrfs_extent_data_ref);
1139 btrfs_set_extent_data_ref_root(leaf, ref,
1141 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1142 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1143 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1145 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1146 num_refs += refs_to_add;
1147 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1150 btrfs_mark_buffer_dirty(leaf);
1153 btrfs_release_path(root, path);
1157 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1158 struct btrfs_root *root,
1159 struct btrfs_path *path,
1162 struct btrfs_key key;
1163 struct btrfs_extent_data_ref *ref1 = NULL;
1164 struct btrfs_shared_data_ref *ref2 = NULL;
1165 struct extent_buffer *leaf;
1169 leaf = path->nodes[0];
1170 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1172 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1173 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1174 struct btrfs_extent_data_ref);
1175 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1176 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1177 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1178 struct btrfs_shared_data_ref);
1179 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1180 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1181 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1182 struct btrfs_extent_ref_v0 *ref0;
1183 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1184 struct btrfs_extent_ref_v0);
1185 num_refs = btrfs_ref_count_v0(leaf, ref0);
1191 BUG_ON(num_refs < refs_to_drop);
1192 num_refs -= refs_to_drop;
1194 if (num_refs == 0) {
1195 ret = btrfs_del_item(trans, root, path);
1197 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1198 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1199 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1200 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1201 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1203 struct btrfs_extent_ref_v0 *ref0;
1204 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1205 struct btrfs_extent_ref_v0);
1206 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1209 btrfs_mark_buffer_dirty(leaf);
1214 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1215 struct btrfs_path *path,
1216 struct btrfs_extent_inline_ref *iref)
1218 struct btrfs_key key;
1219 struct extent_buffer *leaf;
1220 struct btrfs_extent_data_ref *ref1;
1221 struct btrfs_shared_data_ref *ref2;
1224 leaf = path->nodes[0];
1225 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1227 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1228 BTRFS_EXTENT_DATA_REF_KEY) {
1229 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1230 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1232 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1233 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1235 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1236 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1237 struct btrfs_extent_data_ref);
1238 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1239 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1240 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1241 struct btrfs_shared_data_ref);
1242 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1243 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1244 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1245 struct btrfs_extent_ref_v0 *ref0;
1246 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1247 struct btrfs_extent_ref_v0);
1248 num_refs = btrfs_ref_count_v0(leaf, ref0);
1256 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1257 struct btrfs_root *root,
1258 struct btrfs_path *path,
1259 u64 bytenr, u64 parent,
1262 struct btrfs_key key;
1265 key.objectid = bytenr;
1267 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1268 key.offset = parent;
1270 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1271 key.offset = root_objectid;
1274 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1277 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1278 if (ret == -ENOENT && parent) {
1279 btrfs_release_path(root, path);
1280 key.type = BTRFS_EXTENT_REF_V0_KEY;
1281 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1289 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1290 struct btrfs_root *root,
1291 struct btrfs_path *path,
1292 u64 bytenr, u64 parent,
1295 struct btrfs_key key;
1298 key.objectid = bytenr;
1300 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1301 key.offset = parent;
1303 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1304 key.offset = root_objectid;
1307 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1308 btrfs_release_path(root, path);
1312 static inline int extent_ref_type(u64 parent, u64 owner)
1315 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1317 type = BTRFS_SHARED_BLOCK_REF_KEY;
1319 type = BTRFS_TREE_BLOCK_REF_KEY;
1322 type = BTRFS_SHARED_DATA_REF_KEY;
1324 type = BTRFS_EXTENT_DATA_REF_KEY;
1329 static int find_next_key(struct btrfs_path *path, int level,
1330 struct btrfs_key *key)
1333 for (; level < BTRFS_MAX_LEVEL; level++) {
1334 if (!path->nodes[level])
1336 if (path->slots[level] + 1 >=
1337 btrfs_header_nritems(path->nodes[level]))
1340 btrfs_item_key_to_cpu(path->nodes[level], key,
1341 path->slots[level] + 1);
1343 btrfs_node_key_to_cpu(path->nodes[level], key,
1344 path->slots[level] + 1);
1351 * look for inline back ref. if back ref is found, *ref_ret is set
1352 * to the address of inline back ref, and 0 is returned.
1354 * if back ref isn't found, *ref_ret is set to the address where it
1355 * should be inserted, and -ENOENT is returned.
1357 * if insert is true and there are too many inline back refs, the path
1358 * points to the extent item, and -EAGAIN is returned.
1360 * NOTE: inline back refs are ordered in the same way that back ref
1361 * items in the tree are ordered.
1363 static noinline_for_stack
1364 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1365 struct btrfs_root *root,
1366 struct btrfs_path *path,
1367 struct btrfs_extent_inline_ref **ref_ret,
1368 u64 bytenr, u64 num_bytes,
1369 u64 parent, u64 root_objectid,
1370 u64 owner, u64 offset, int insert)
1372 struct btrfs_key key;
1373 struct extent_buffer *leaf;
1374 struct btrfs_extent_item *ei;
1375 struct btrfs_extent_inline_ref *iref;
1386 key.objectid = bytenr;
1387 key.type = BTRFS_EXTENT_ITEM_KEY;
1388 key.offset = num_bytes;
1390 want = extent_ref_type(parent, owner);
1392 extra_size = btrfs_extent_inline_ref_size(want);
1393 path->keep_locks = 1;
1396 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1403 leaf = path->nodes[0];
1404 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1405 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1406 if (item_size < sizeof(*ei)) {
1411 ret = convert_extent_item_v0(trans, root, path, owner,
1417 leaf = path->nodes[0];
1418 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1421 BUG_ON(item_size < sizeof(*ei));
1423 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1424 flags = btrfs_extent_flags(leaf, ei);
1426 ptr = (unsigned long)(ei + 1);
1427 end = (unsigned long)ei + item_size;
1429 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1430 ptr += sizeof(struct btrfs_tree_block_info);
1433 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1442 iref = (struct btrfs_extent_inline_ref *)ptr;
1443 type = btrfs_extent_inline_ref_type(leaf, iref);
1447 ptr += btrfs_extent_inline_ref_size(type);
1451 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1452 struct btrfs_extent_data_ref *dref;
1453 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1454 if (match_extent_data_ref(leaf, dref, root_objectid,
1459 if (hash_extent_data_ref_item(leaf, dref) <
1460 hash_extent_data_ref(root_objectid, owner, offset))
1464 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1466 if (parent == ref_offset) {
1470 if (ref_offset < parent)
1473 if (root_objectid == ref_offset) {
1477 if (ref_offset < root_objectid)
1481 ptr += btrfs_extent_inline_ref_size(type);
1483 if (err == -ENOENT && insert) {
1484 if (item_size + extra_size >=
1485 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1490 * To add new inline back ref, we have to make sure
1491 * there is no corresponding back ref item.
1492 * For simplicity, we just do not add new inline back
1493 * ref if there is any kind of item for this block
1495 if (find_next_key(path, 0, &key) == 0 &&
1496 key.objectid == bytenr &&
1497 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1502 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1505 path->keep_locks = 0;
1506 btrfs_unlock_up_safe(path, 1);
1512 * helper to add new inline back ref
1514 static noinline_for_stack
1515 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1516 struct btrfs_root *root,
1517 struct btrfs_path *path,
1518 struct btrfs_extent_inline_ref *iref,
1519 u64 parent, u64 root_objectid,
1520 u64 owner, u64 offset, int refs_to_add,
1521 struct btrfs_delayed_extent_op *extent_op)
1523 struct extent_buffer *leaf;
1524 struct btrfs_extent_item *ei;
1527 unsigned long item_offset;
1533 leaf = path->nodes[0];
1534 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1535 item_offset = (unsigned long)iref - (unsigned long)ei;
1537 type = extent_ref_type(parent, owner);
1538 size = btrfs_extent_inline_ref_size(type);
1540 ret = btrfs_extend_item(trans, root, path, size);
1543 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1544 refs = btrfs_extent_refs(leaf, ei);
1545 refs += refs_to_add;
1546 btrfs_set_extent_refs(leaf, ei, refs);
1548 __run_delayed_extent_op(extent_op, leaf, ei);
1550 ptr = (unsigned long)ei + item_offset;
1551 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1552 if (ptr < end - size)
1553 memmove_extent_buffer(leaf, ptr + size, ptr,
1556 iref = (struct btrfs_extent_inline_ref *)ptr;
1557 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1558 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1559 struct btrfs_extent_data_ref *dref;
1560 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1561 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1562 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1563 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1564 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1565 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1566 struct btrfs_shared_data_ref *sref;
1567 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1568 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1569 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1570 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1571 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1573 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1575 btrfs_mark_buffer_dirty(leaf);
1579 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1580 struct btrfs_root *root,
1581 struct btrfs_path *path,
1582 struct btrfs_extent_inline_ref **ref_ret,
1583 u64 bytenr, u64 num_bytes, u64 parent,
1584 u64 root_objectid, u64 owner, u64 offset)
1588 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1589 bytenr, num_bytes, parent,
1590 root_objectid, owner, offset, 0);
1594 btrfs_release_path(root, path);
1597 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1598 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1601 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1602 root_objectid, owner, offset);
1608 * helper to update/remove inline back ref
1610 static noinline_for_stack
1611 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1612 struct btrfs_root *root,
1613 struct btrfs_path *path,
1614 struct btrfs_extent_inline_ref *iref,
1616 struct btrfs_delayed_extent_op *extent_op)
1618 struct extent_buffer *leaf;
1619 struct btrfs_extent_item *ei;
1620 struct btrfs_extent_data_ref *dref = NULL;
1621 struct btrfs_shared_data_ref *sref = NULL;
1630 leaf = path->nodes[0];
1631 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1632 refs = btrfs_extent_refs(leaf, ei);
1633 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1634 refs += refs_to_mod;
1635 btrfs_set_extent_refs(leaf, ei, refs);
1637 __run_delayed_extent_op(extent_op, leaf, ei);
1639 type = btrfs_extent_inline_ref_type(leaf, iref);
1641 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1642 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1643 refs = btrfs_extent_data_ref_count(leaf, dref);
1644 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1645 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1646 refs = btrfs_shared_data_ref_count(leaf, sref);
1649 BUG_ON(refs_to_mod != -1);
1652 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1653 refs += refs_to_mod;
1656 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1657 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1659 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1661 size = btrfs_extent_inline_ref_size(type);
1662 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1663 ptr = (unsigned long)iref;
1664 end = (unsigned long)ei + item_size;
1665 if (ptr + size < end)
1666 memmove_extent_buffer(leaf, ptr, ptr + size,
1669 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1672 btrfs_mark_buffer_dirty(leaf);
1676 static noinline_for_stack
1677 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1678 struct btrfs_root *root,
1679 struct btrfs_path *path,
1680 u64 bytenr, u64 num_bytes, u64 parent,
1681 u64 root_objectid, u64 owner,
1682 u64 offset, int refs_to_add,
1683 struct btrfs_delayed_extent_op *extent_op)
1685 struct btrfs_extent_inline_ref *iref;
1688 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1689 bytenr, num_bytes, parent,
1690 root_objectid, owner, offset, 1);
1692 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1693 ret = update_inline_extent_backref(trans, root, path, iref,
1694 refs_to_add, extent_op);
1695 } else if (ret == -ENOENT) {
1696 ret = setup_inline_extent_backref(trans, root, path, iref,
1697 parent, root_objectid,
1698 owner, offset, refs_to_add,
1704 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1705 struct btrfs_root *root,
1706 struct btrfs_path *path,
1707 u64 bytenr, u64 parent, u64 root_objectid,
1708 u64 owner, u64 offset, int refs_to_add)
1711 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1712 BUG_ON(refs_to_add != 1);
1713 ret = insert_tree_block_ref(trans, root, path, bytenr,
1714 parent, root_objectid);
1716 ret = insert_extent_data_ref(trans, root, path, bytenr,
1717 parent, root_objectid,
1718 owner, offset, refs_to_add);
1723 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1724 struct btrfs_root *root,
1725 struct btrfs_path *path,
1726 struct btrfs_extent_inline_ref *iref,
1727 int refs_to_drop, int is_data)
1731 BUG_ON(!is_data && refs_to_drop != 1);
1733 ret = update_inline_extent_backref(trans, root, path, iref,
1734 -refs_to_drop, NULL);
1735 } else if (is_data) {
1736 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1738 ret = btrfs_del_item(trans, root, path);
1743 static void btrfs_issue_discard(struct block_device *bdev,
1746 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL, 0);
1749 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1753 u64 map_length = num_bytes;
1754 struct btrfs_multi_bio *multi = NULL;
1756 if (!btrfs_test_opt(root, DISCARD))
1759 /* Tell the block device(s) that the sectors can be discarded */
1760 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1761 bytenr, &map_length, &multi, 0);
1763 struct btrfs_bio_stripe *stripe = multi->stripes;
1766 if (map_length > num_bytes)
1767 map_length = num_bytes;
1769 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1770 btrfs_issue_discard(stripe->dev->bdev,
1780 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1781 struct btrfs_root *root,
1782 u64 bytenr, u64 num_bytes, u64 parent,
1783 u64 root_objectid, u64 owner, u64 offset)
1786 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1787 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1789 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1790 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1791 parent, root_objectid, (int)owner,
1792 BTRFS_ADD_DELAYED_REF, NULL);
1794 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1795 parent, root_objectid, owner, offset,
1796 BTRFS_ADD_DELAYED_REF, NULL);
1801 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1802 struct btrfs_root *root,
1803 u64 bytenr, u64 num_bytes,
1804 u64 parent, u64 root_objectid,
1805 u64 owner, u64 offset, int refs_to_add,
1806 struct btrfs_delayed_extent_op *extent_op)
1808 struct btrfs_path *path;
1809 struct extent_buffer *leaf;
1810 struct btrfs_extent_item *item;
1815 path = btrfs_alloc_path();
1820 path->leave_spinning = 1;
1821 /* this will setup the path even if it fails to insert the back ref */
1822 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1823 path, bytenr, num_bytes, parent,
1824 root_objectid, owner, offset,
1825 refs_to_add, extent_op);
1829 if (ret != -EAGAIN) {
1834 leaf = path->nodes[0];
1835 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1836 refs = btrfs_extent_refs(leaf, item);
1837 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1839 __run_delayed_extent_op(extent_op, leaf, item);
1841 btrfs_mark_buffer_dirty(leaf);
1842 btrfs_release_path(root->fs_info->extent_root, path);
1845 path->leave_spinning = 1;
1847 /* now insert the actual backref */
1848 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1849 path, bytenr, parent, root_objectid,
1850 owner, offset, refs_to_add);
1853 btrfs_free_path(path);
1857 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1858 struct btrfs_root *root,
1859 struct btrfs_delayed_ref_node *node,
1860 struct btrfs_delayed_extent_op *extent_op,
1861 int insert_reserved)
1864 struct btrfs_delayed_data_ref *ref;
1865 struct btrfs_key ins;
1870 ins.objectid = node->bytenr;
1871 ins.offset = node->num_bytes;
1872 ins.type = BTRFS_EXTENT_ITEM_KEY;
1874 ref = btrfs_delayed_node_to_data_ref(node);
1875 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1876 parent = ref->parent;
1878 ref_root = ref->root;
1880 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1882 BUG_ON(extent_op->update_key);
1883 flags |= extent_op->flags_to_set;
1885 ret = alloc_reserved_file_extent(trans, root,
1886 parent, ref_root, flags,
1887 ref->objectid, ref->offset,
1888 &ins, node->ref_mod);
1889 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1890 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1891 node->num_bytes, parent,
1892 ref_root, ref->objectid,
1893 ref->offset, node->ref_mod,
1895 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1896 ret = __btrfs_free_extent(trans, root, node->bytenr,
1897 node->num_bytes, parent,
1898 ref_root, ref->objectid,
1899 ref->offset, node->ref_mod,
1907 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1908 struct extent_buffer *leaf,
1909 struct btrfs_extent_item *ei)
1911 u64 flags = btrfs_extent_flags(leaf, ei);
1912 if (extent_op->update_flags) {
1913 flags |= extent_op->flags_to_set;
1914 btrfs_set_extent_flags(leaf, ei, flags);
1917 if (extent_op->update_key) {
1918 struct btrfs_tree_block_info *bi;
1919 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1920 bi = (struct btrfs_tree_block_info *)(ei + 1);
1921 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1925 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1926 struct btrfs_root *root,
1927 struct btrfs_delayed_ref_node *node,
1928 struct btrfs_delayed_extent_op *extent_op)
1930 struct btrfs_key key;
1931 struct btrfs_path *path;
1932 struct btrfs_extent_item *ei;
1933 struct extent_buffer *leaf;
1938 path = btrfs_alloc_path();
1942 key.objectid = node->bytenr;
1943 key.type = BTRFS_EXTENT_ITEM_KEY;
1944 key.offset = node->num_bytes;
1947 path->leave_spinning = 1;
1948 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1959 leaf = path->nodes[0];
1960 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1961 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1962 if (item_size < sizeof(*ei)) {
1963 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1969 leaf = path->nodes[0];
1970 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1973 BUG_ON(item_size < sizeof(*ei));
1974 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1975 __run_delayed_extent_op(extent_op, leaf, ei);
1977 btrfs_mark_buffer_dirty(leaf);
1979 btrfs_free_path(path);
1983 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1984 struct btrfs_root *root,
1985 struct btrfs_delayed_ref_node *node,
1986 struct btrfs_delayed_extent_op *extent_op,
1987 int insert_reserved)
1990 struct btrfs_delayed_tree_ref *ref;
1991 struct btrfs_key ins;
1995 ins.objectid = node->bytenr;
1996 ins.offset = node->num_bytes;
1997 ins.type = BTRFS_EXTENT_ITEM_KEY;
1999 ref = btrfs_delayed_node_to_tree_ref(node);
2000 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2001 parent = ref->parent;
2003 ref_root = ref->root;
2005 BUG_ON(node->ref_mod != 1);
2006 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2007 BUG_ON(!extent_op || !extent_op->update_flags ||
2008 !extent_op->update_key);
2009 ret = alloc_reserved_tree_block(trans, root,
2011 extent_op->flags_to_set,
2014 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2015 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2016 node->num_bytes, parent, ref_root,
2017 ref->level, 0, 1, extent_op);
2018 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2019 ret = __btrfs_free_extent(trans, root, node->bytenr,
2020 node->num_bytes, parent, ref_root,
2021 ref->level, 0, 1, extent_op);
2028 /* helper function to actually process a single delayed ref entry */
2029 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2030 struct btrfs_root *root,
2031 struct btrfs_delayed_ref_node *node,
2032 struct btrfs_delayed_extent_op *extent_op,
2033 int insert_reserved)
2036 if (btrfs_delayed_ref_is_head(node)) {
2037 struct btrfs_delayed_ref_head *head;
2039 * we've hit the end of the chain and we were supposed
2040 * to insert this extent into the tree. But, it got
2041 * deleted before we ever needed to insert it, so all
2042 * we have to do is clean up the accounting
2045 head = btrfs_delayed_node_to_head(node);
2046 if (insert_reserved) {
2047 btrfs_pin_extent(root, node->bytenr,
2048 node->num_bytes, 1);
2049 if (head->is_data) {
2050 ret = btrfs_del_csums(trans, root,
2056 mutex_unlock(&head->mutex);
2060 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2061 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2062 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2064 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2065 node->type == BTRFS_SHARED_DATA_REF_KEY)
2066 ret = run_delayed_data_ref(trans, root, node, extent_op,
2073 static noinline struct btrfs_delayed_ref_node *
2074 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2076 struct rb_node *node;
2077 struct btrfs_delayed_ref_node *ref;
2078 int action = BTRFS_ADD_DELAYED_REF;
2081 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2082 * this prevents ref count from going down to zero when
2083 * there still are pending delayed ref.
2085 node = rb_prev(&head->node.rb_node);
2089 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2091 if (ref->bytenr != head->node.bytenr)
2093 if (ref->action == action)
2095 node = rb_prev(node);
2097 if (action == BTRFS_ADD_DELAYED_REF) {
2098 action = BTRFS_DROP_DELAYED_REF;
2104 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2105 struct btrfs_root *root,
2106 struct list_head *cluster)
2108 struct btrfs_delayed_ref_root *delayed_refs;
2109 struct btrfs_delayed_ref_node *ref;
2110 struct btrfs_delayed_ref_head *locked_ref = NULL;
2111 struct btrfs_delayed_extent_op *extent_op;
2114 int must_insert_reserved = 0;
2116 delayed_refs = &trans->transaction->delayed_refs;
2119 /* pick a new head ref from the cluster list */
2120 if (list_empty(cluster))
2123 locked_ref = list_entry(cluster->next,
2124 struct btrfs_delayed_ref_head, cluster);
2126 /* grab the lock that says we are going to process
2127 * all the refs for this head */
2128 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2131 * we may have dropped the spin lock to get the head
2132 * mutex lock, and that might have given someone else
2133 * time to free the head. If that's true, it has been
2134 * removed from our list and we can move on.
2136 if (ret == -EAGAIN) {
2144 * record the must insert reserved flag before we
2145 * drop the spin lock.
2147 must_insert_reserved = locked_ref->must_insert_reserved;
2148 locked_ref->must_insert_reserved = 0;
2150 extent_op = locked_ref->extent_op;
2151 locked_ref->extent_op = NULL;
2154 * locked_ref is the head node, so we have to go one
2155 * node back for any delayed ref updates
2157 ref = select_delayed_ref(locked_ref);
2159 /* All delayed refs have been processed, Go ahead
2160 * and send the head node to run_one_delayed_ref,
2161 * so that any accounting fixes can happen
2163 ref = &locked_ref->node;
2165 if (extent_op && must_insert_reserved) {
2171 spin_unlock(&delayed_refs->lock);
2173 ret = run_delayed_extent_op(trans, root,
2179 spin_lock(&delayed_refs->lock);
2183 list_del_init(&locked_ref->cluster);
2188 rb_erase(&ref->rb_node, &delayed_refs->root);
2189 delayed_refs->num_entries--;
2191 spin_unlock(&delayed_refs->lock);
2193 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2194 must_insert_reserved);
2197 btrfs_put_delayed_ref(ref);
2202 spin_lock(&delayed_refs->lock);
2208 * this starts processing the delayed reference count updates and
2209 * extent insertions we have queued up so far. count can be
2210 * 0, which means to process everything in the tree at the start
2211 * of the run (but not newly added entries), or it can be some target
2212 * number you'd like to process.
2214 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2215 struct btrfs_root *root, unsigned long count)
2217 struct rb_node *node;
2218 struct btrfs_delayed_ref_root *delayed_refs;
2219 struct btrfs_delayed_ref_node *ref;
2220 struct list_head cluster;
2222 int run_all = count == (unsigned long)-1;
2225 if (root == root->fs_info->extent_root)
2226 root = root->fs_info->tree_root;
2228 delayed_refs = &trans->transaction->delayed_refs;
2229 INIT_LIST_HEAD(&cluster);
2231 spin_lock(&delayed_refs->lock);
2233 count = delayed_refs->num_entries * 2;
2237 if (!(run_all || run_most) &&
2238 delayed_refs->num_heads_ready < 64)
2242 * go find something we can process in the rbtree. We start at
2243 * the beginning of the tree, and then build a cluster
2244 * of refs to process starting at the first one we are able to
2247 ret = btrfs_find_ref_cluster(trans, &cluster,
2248 delayed_refs->run_delayed_start);
2252 ret = run_clustered_refs(trans, root, &cluster);
2255 count -= min_t(unsigned long, ret, count);
2262 node = rb_first(&delayed_refs->root);
2265 count = (unsigned long)-1;
2268 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2270 if (btrfs_delayed_ref_is_head(ref)) {
2271 struct btrfs_delayed_ref_head *head;
2273 head = btrfs_delayed_node_to_head(ref);
2274 atomic_inc(&ref->refs);
2276 spin_unlock(&delayed_refs->lock);
2277 mutex_lock(&head->mutex);
2278 mutex_unlock(&head->mutex);
2280 btrfs_put_delayed_ref(ref);
2284 node = rb_next(node);
2286 spin_unlock(&delayed_refs->lock);
2287 schedule_timeout(1);
2291 spin_unlock(&delayed_refs->lock);
2295 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2296 struct btrfs_root *root,
2297 u64 bytenr, u64 num_bytes, u64 flags,
2300 struct btrfs_delayed_extent_op *extent_op;
2303 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2307 extent_op->flags_to_set = flags;
2308 extent_op->update_flags = 1;
2309 extent_op->update_key = 0;
2310 extent_op->is_data = is_data ? 1 : 0;
2312 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2318 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2319 struct btrfs_root *root,
2320 struct btrfs_path *path,
2321 u64 objectid, u64 offset, u64 bytenr)
2323 struct btrfs_delayed_ref_head *head;
2324 struct btrfs_delayed_ref_node *ref;
2325 struct btrfs_delayed_data_ref *data_ref;
2326 struct btrfs_delayed_ref_root *delayed_refs;
2327 struct rb_node *node;
2331 delayed_refs = &trans->transaction->delayed_refs;
2332 spin_lock(&delayed_refs->lock);
2333 head = btrfs_find_delayed_ref_head(trans, bytenr);
2337 if (!mutex_trylock(&head->mutex)) {
2338 atomic_inc(&head->node.refs);
2339 spin_unlock(&delayed_refs->lock);
2341 btrfs_release_path(root->fs_info->extent_root, path);
2343 mutex_lock(&head->mutex);
2344 mutex_unlock(&head->mutex);
2345 btrfs_put_delayed_ref(&head->node);
2349 node = rb_prev(&head->node.rb_node);
2353 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2355 if (ref->bytenr != bytenr)
2359 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2362 data_ref = btrfs_delayed_node_to_data_ref(ref);
2364 node = rb_prev(node);
2366 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2367 if (ref->bytenr == bytenr)
2371 if (data_ref->root != root->root_key.objectid ||
2372 data_ref->objectid != objectid || data_ref->offset != offset)
2377 mutex_unlock(&head->mutex);
2379 spin_unlock(&delayed_refs->lock);
2383 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2384 struct btrfs_root *root,
2385 struct btrfs_path *path,
2386 u64 objectid, u64 offset, u64 bytenr)
2388 struct btrfs_root *extent_root = root->fs_info->extent_root;
2389 struct extent_buffer *leaf;
2390 struct btrfs_extent_data_ref *ref;
2391 struct btrfs_extent_inline_ref *iref;
2392 struct btrfs_extent_item *ei;
2393 struct btrfs_key key;
2397 key.objectid = bytenr;
2398 key.offset = (u64)-1;
2399 key.type = BTRFS_EXTENT_ITEM_KEY;
2401 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2407 if (path->slots[0] == 0)
2411 leaf = path->nodes[0];
2412 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2414 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2418 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2419 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2420 if (item_size < sizeof(*ei)) {
2421 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2425 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2427 if (item_size != sizeof(*ei) +
2428 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2431 if (btrfs_extent_generation(leaf, ei) <=
2432 btrfs_root_last_snapshot(&root->root_item))
2435 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2436 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2437 BTRFS_EXTENT_DATA_REF_KEY)
2440 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2441 if (btrfs_extent_refs(leaf, ei) !=
2442 btrfs_extent_data_ref_count(leaf, ref) ||
2443 btrfs_extent_data_ref_root(leaf, ref) !=
2444 root->root_key.objectid ||
2445 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2446 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2454 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2455 struct btrfs_root *root,
2456 u64 objectid, u64 offset, u64 bytenr)
2458 struct btrfs_path *path;
2462 path = btrfs_alloc_path();
2467 ret = check_committed_ref(trans, root, path, objectid,
2469 if (ret && ret != -ENOENT)
2472 ret2 = check_delayed_ref(trans, root, path, objectid,
2474 } while (ret2 == -EAGAIN);
2476 if (ret2 && ret2 != -ENOENT) {
2481 if (ret != -ENOENT || ret2 != -ENOENT)
2484 btrfs_free_path(path);
2485 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2491 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2492 struct extent_buffer *buf, u32 nr_extents)
2494 struct btrfs_key key;
2495 struct btrfs_file_extent_item *fi;
2503 if (!root->ref_cows)
2506 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2508 root_gen = root->root_key.offset;
2511 root_gen = trans->transid - 1;
2514 level = btrfs_header_level(buf);
2515 nritems = btrfs_header_nritems(buf);
2518 struct btrfs_leaf_ref *ref;
2519 struct btrfs_extent_info *info;
2521 ref = btrfs_alloc_leaf_ref(root, nr_extents);
2527 ref->root_gen = root_gen;
2528 ref->bytenr = buf->start;
2529 ref->owner = btrfs_header_owner(buf);
2530 ref->generation = btrfs_header_generation(buf);
2531 ref->nritems = nr_extents;
2532 info = ref->extents;
2534 for (i = 0; nr_extents > 0 && i < nritems; i++) {
2536 btrfs_item_key_to_cpu(buf, &key, i);
2537 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2539 fi = btrfs_item_ptr(buf, i,
2540 struct btrfs_file_extent_item);
2541 if (btrfs_file_extent_type(buf, fi) ==
2542 BTRFS_FILE_EXTENT_INLINE)
2544 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2545 if (disk_bytenr == 0)
2548 info->bytenr = disk_bytenr;
2550 btrfs_file_extent_disk_num_bytes(buf, fi);
2551 info->objectid = key.objectid;
2552 info->offset = key.offset;
2556 ret = btrfs_add_leaf_ref(root, ref, shared);
2557 if (ret == -EEXIST && shared) {
2558 struct btrfs_leaf_ref *old;
2559 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2561 btrfs_remove_leaf_ref(root, old);
2562 btrfs_free_leaf_ref(root, old);
2563 ret = btrfs_add_leaf_ref(root, ref, shared);
2566 btrfs_free_leaf_ref(root, ref);
2572 /* when a block goes through cow, we update the reference counts of
2573 * everything that block points to. The internal pointers of the block
2574 * can be in just about any order, and it is likely to have clusters of
2575 * things that are close together and clusters of things that are not.
2577 * To help reduce the seeks that come with updating all of these reference
2578 * counts, sort them by byte number before actual updates are done.
2580 * struct refsort is used to match byte number to slot in the btree block.
2581 * we sort based on the byte number and then use the slot to actually
2584 * struct refsort is smaller than strcut btrfs_item and smaller than
2585 * struct btrfs_key_ptr. Since we're currently limited to the page size
2586 * for a btree block, there's no way for a kmalloc of refsorts for a
2587 * single node to be bigger than a page.
2595 * for passing into sort()
2597 static int refsort_cmp(const void *a_void, const void *b_void)
2599 const struct refsort *a = a_void;
2600 const struct refsort *b = b_void;
2602 if (a->bytenr < b->bytenr)
2604 if (a->bytenr > b->bytenr)
2610 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2611 struct btrfs_root *root,
2612 struct extent_buffer *buf,
2613 int full_backref, int inc)
2620 struct btrfs_key key;
2621 struct btrfs_file_extent_item *fi;
2625 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2626 u64, u64, u64, u64, u64, u64);
2628 ref_root = btrfs_header_owner(buf);
2629 nritems = btrfs_header_nritems(buf);
2630 level = btrfs_header_level(buf);
2632 if (!root->ref_cows && level == 0)
2636 process_func = btrfs_inc_extent_ref;
2638 process_func = btrfs_free_extent;
2641 parent = buf->start;
2645 for (i = 0; i < nritems; i++) {
2647 btrfs_item_key_to_cpu(buf, &key, i);
2648 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2650 fi = btrfs_item_ptr(buf, i,
2651 struct btrfs_file_extent_item);
2652 if (btrfs_file_extent_type(buf, fi) ==
2653 BTRFS_FILE_EXTENT_INLINE)
2655 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2659 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2660 key.offset -= btrfs_file_extent_offset(buf, fi);
2661 ret = process_func(trans, root, bytenr, num_bytes,
2662 parent, ref_root, key.objectid,
2667 bytenr = btrfs_node_blockptr(buf, i);
2668 num_bytes = btrfs_level_size(root, level - 1);
2669 ret = process_func(trans, root, bytenr, num_bytes,
2670 parent, ref_root, level - 1, 0);
2681 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2682 struct extent_buffer *buf, int full_backref)
2684 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2687 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2688 struct extent_buffer *buf, int full_backref)
2690 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2693 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2694 struct btrfs_root *root,
2695 struct btrfs_path *path,
2696 struct btrfs_block_group_cache *cache)
2699 struct btrfs_root *extent_root = root->fs_info->extent_root;
2701 struct extent_buffer *leaf;
2703 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2708 leaf = path->nodes[0];
2709 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2710 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2711 btrfs_mark_buffer_dirty(leaf);
2712 btrfs_release_path(extent_root, path);
2720 static struct btrfs_block_group_cache *
2721 next_block_group(struct btrfs_root *root,
2722 struct btrfs_block_group_cache *cache)
2724 struct rb_node *node;
2725 spin_lock(&root->fs_info->block_group_cache_lock);
2726 node = rb_next(&cache->cache_node);
2727 btrfs_put_block_group(cache);
2729 cache = rb_entry(node, struct btrfs_block_group_cache,
2731 btrfs_get_block_group(cache);
2734 spin_unlock(&root->fs_info->block_group_cache_lock);
2738 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2739 struct btrfs_trans_handle *trans,
2740 struct btrfs_path *path)
2742 struct btrfs_root *root = block_group->fs_info->tree_root;
2743 struct inode *inode = NULL;
2745 int dcs = BTRFS_DC_ERROR;
2751 * If this block group is smaller than 100 megs don't bother caching the
2754 if (block_group->key.offset < (100 * 1024 * 1024)) {
2755 spin_lock(&block_group->lock);
2756 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2757 spin_unlock(&block_group->lock);
2762 inode = lookup_free_space_inode(root, block_group, path);
2763 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2764 ret = PTR_ERR(inode);
2765 btrfs_release_path(root, path);
2769 if (IS_ERR(inode)) {
2773 if (block_group->ro)
2776 ret = create_free_space_inode(root, trans, block_group, path);
2783 * We want to set the generation to 0, that way if anything goes wrong
2784 * from here on out we know not to trust this cache when we load up next
2787 BTRFS_I(inode)->generation = 0;
2788 ret = btrfs_update_inode(trans, root, inode);
2791 if (i_size_read(inode) > 0) {
2792 ret = btrfs_truncate_free_space_cache(root, trans, path,
2798 spin_lock(&block_group->lock);
2799 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2800 /* We're not cached, don't bother trying to write stuff out */
2801 dcs = BTRFS_DC_WRITTEN;
2802 spin_unlock(&block_group->lock);
2805 spin_unlock(&block_group->lock);
2807 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2812 * Just to make absolutely sure we have enough space, we're going to
2813 * preallocate 12 pages worth of space for each block group. In
2814 * practice we ought to use at most 8, but we need extra space so we can
2815 * add our header and have a terminator between the extents and the
2819 num_pages *= PAGE_CACHE_SIZE;
2821 ret = btrfs_check_data_free_space(inode, num_pages);
2825 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2826 num_pages, num_pages,
2829 dcs = BTRFS_DC_SETUP;
2830 btrfs_free_reserved_data_space(inode, num_pages);
2834 btrfs_release_path(root, path);
2836 spin_lock(&block_group->lock);
2837 block_group->disk_cache_state = dcs;
2838 spin_unlock(&block_group->lock);
2843 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2844 struct btrfs_root *root)
2846 struct btrfs_block_group_cache *cache;
2848 struct btrfs_path *path;
2851 path = btrfs_alloc_path();
2857 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2859 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2861 cache = next_block_group(root, cache);
2869 err = cache_save_setup(cache, trans, path);
2870 last = cache->key.objectid + cache->key.offset;
2871 btrfs_put_block_group(cache);
2876 err = btrfs_run_delayed_refs(trans, root,
2881 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2883 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2884 btrfs_put_block_group(cache);
2890 cache = next_block_group(root, cache);
2899 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2900 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2902 last = cache->key.objectid + cache->key.offset;
2904 err = write_one_cache_group(trans, root, path, cache);
2906 btrfs_put_block_group(cache);
2911 * I don't think this is needed since we're just marking our
2912 * preallocated extent as written, but just in case it can't
2916 err = btrfs_run_delayed_refs(trans, root,
2921 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2924 * Really this shouldn't happen, but it could if we
2925 * couldn't write the entire preallocated extent and
2926 * splitting the extent resulted in a new block.
2929 btrfs_put_block_group(cache);
2932 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2934 cache = next_block_group(root, cache);
2943 btrfs_write_out_cache(root, trans, cache, path);
2946 * If we didn't have an error then the cache state is still
2947 * NEED_WRITE, so we can set it to WRITTEN.
2949 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2950 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2951 last = cache->key.objectid + cache->key.offset;
2952 btrfs_put_block_group(cache);
2955 btrfs_free_path(path);
2959 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2961 struct btrfs_block_group_cache *block_group;
2964 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2965 if (!block_group || block_group->ro)
2968 btrfs_put_block_group(block_group);
2972 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2973 u64 total_bytes, u64 bytes_used,
2974 struct btrfs_space_info **space_info)
2976 struct btrfs_space_info *found;
2980 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2981 BTRFS_BLOCK_GROUP_RAID10))
2986 found = __find_space_info(info, flags);
2988 spin_lock(&found->lock);
2989 found->total_bytes += total_bytes;
2990 found->disk_total += total_bytes * factor;
2991 found->bytes_used += bytes_used;
2992 found->disk_used += bytes_used * factor;
2994 spin_unlock(&found->lock);
2995 *space_info = found;
2998 found = kzalloc(sizeof(*found), GFP_NOFS);
3002 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3003 INIT_LIST_HEAD(&found->block_groups[i]);
3004 init_rwsem(&found->groups_sem);
3005 spin_lock_init(&found->lock);
3006 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
3007 BTRFS_BLOCK_GROUP_SYSTEM |
3008 BTRFS_BLOCK_GROUP_METADATA);
3009 found->total_bytes = total_bytes;
3010 found->disk_total = total_bytes * factor;
3011 found->bytes_used = bytes_used;
3012 found->disk_used = bytes_used * factor;
3013 found->bytes_pinned = 0;
3014 found->bytes_reserved = 0;
3015 found->bytes_readonly = 0;
3016 found->bytes_may_use = 0;
3018 found->force_alloc = 0;
3019 *space_info = found;
3020 list_add_rcu(&found->list, &info->space_info);
3021 atomic_set(&found->caching_threads, 0);
3025 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3027 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
3028 BTRFS_BLOCK_GROUP_RAID1 |
3029 BTRFS_BLOCK_GROUP_RAID10 |
3030 BTRFS_BLOCK_GROUP_DUP);
3032 if (flags & BTRFS_BLOCK_GROUP_DATA)
3033 fs_info->avail_data_alloc_bits |= extra_flags;
3034 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3035 fs_info->avail_metadata_alloc_bits |= extra_flags;
3036 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3037 fs_info->avail_system_alloc_bits |= extra_flags;
3041 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3044 * we add in the count of missing devices because we want
3045 * to make sure that any RAID levels on a degraded FS
3046 * continue to be honored.
3048 u64 num_devices = root->fs_info->fs_devices->rw_devices +
3049 root->fs_info->fs_devices->missing_devices;
3051 if (num_devices == 1)
3052 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3053 if (num_devices < 4)
3054 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3056 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3057 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3058 BTRFS_BLOCK_GROUP_RAID10))) {
3059 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3062 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3063 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3064 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3067 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3068 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3069 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3070 (flags & BTRFS_BLOCK_GROUP_DUP)))
3071 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3075 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3077 if (flags & BTRFS_BLOCK_GROUP_DATA)
3078 flags |= root->fs_info->avail_data_alloc_bits &
3079 root->fs_info->data_alloc_profile;
3080 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3081 flags |= root->fs_info->avail_system_alloc_bits &
3082 root->fs_info->system_alloc_profile;
3083 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3084 flags |= root->fs_info->avail_metadata_alloc_bits &
3085 root->fs_info->metadata_alloc_profile;
3086 return btrfs_reduce_alloc_profile(root, flags);
3089 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3094 flags = BTRFS_BLOCK_GROUP_DATA;
3095 else if (root == root->fs_info->chunk_root)
3096 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3098 flags = BTRFS_BLOCK_GROUP_METADATA;
3100 return get_alloc_profile(root, flags);
3103 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3105 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3106 BTRFS_BLOCK_GROUP_DATA);
3110 * This will check the space that the inode allocates from to make sure we have
3111 * enough space for bytes.
3113 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3115 struct btrfs_space_info *data_sinfo;
3116 struct btrfs_root *root = BTRFS_I(inode)->root;
3118 int ret = 0, committed = 0, alloc_chunk = 1;
3120 /* make sure bytes are sectorsize aligned */
3121 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3123 if (root == root->fs_info->tree_root) {
3128 data_sinfo = BTRFS_I(inode)->space_info;
3133 /* make sure we have enough space to handle the data first */
3134 spin_lock(&data_sinfo->lock);
3135 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3136 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3137 data_sinfo->bytes_may_use;
3139 if (used + bytes > data_sinfo->total_bytes) {
3140 struct btrfs_trans_handle *trans;
3143 * if we don't have enough free bytes in this space then we need
3144 * to alloc a new chunk.
3146 if (!data_sinfo->full && alloc_chunk) {
3149 data_sinfo->force_alloc = 1;
3150 spin_unlock(&data_sinfo->lock);
3152 alloc_target = btrfs_get_alloc_profile(root, 1);
3153 trans = btrfs_join_transaction(root, 1);
3155 return PTR_ERR(trans);
3157 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3158 bytes + 2 * 1024 * 1024,
3160 btrfs_end_transaction(trans, root);
3169 btrfs_set_inode_space_info(root, inode);
3170 data_sinfo = BTRFS_I(inode)->space_info;
3174 spin_unlock(&data_sinfo->lock);
3176 /* commit the current transaction and try again */
3178 if (!committed && !root->fs_info->open_ioctl_trans) {
3180 trans = btrfs_join_transaction(root, 1);
3182 return PTR_ERR(trans);
3183 ret = btrfs_commit_transaction(trans, root);
3189 #if 0 /* I hope we never need this code again, just in case */
3190 printk(KERN_ERR "no space left, need %llu, %llu bytes_used, "
3191 "%llu bytes_reserved, " "%llu bytes_pinned, "
3192 "%llu bytes_readonly, %llu may use %llu total\n",
3193 (unsigned long long)bytes,
3194 (unsigned long long)data_sinfo->bytes_used,
3195 (unsigned long long)data_sinfo->bytes_reserved,
3196 (unsigned long long)data_sinfo->bytes_pinned,
3197 (unsigned long long)data_sinfo->bytes_readonly,
3198 (unsigned long long)data_sinfo->bytes_may_use,
3199 (unsigned long long)data_sinfo->total_bytes);
3203 data_sinfo->bytes_may_use += bytes;
3204 BTRFS_I(inode)->reserved_bytes += bytes;
3205 spin_unlock(&data_sinfo->lock);
3211 * called when we are clearing an delalloc extent from the
3212 * inode's io_tree or there was an error for whatever reason
3213 * after calling btrfs_check_data_free_space
3215 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3217 struct btrfs_root *root = BTRFS_I(inode)->root;
3218 struct btrfs_space_info *data_sinfo;
3220 /* make sure bytes are sectorsize aligned */
3221 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3223 data_sinfo = BTRFS_I(inode)->space_info;
3224 spin_lock(&data_sinfo->lock);
3225 data_sinfo->bytes_may_use -= bytes;
3226 BTRFS_I(inode)->reserved_bytes -= bytes;
3227 spin_unlock(&data_sinfo->lock);
3230 static void force_metadata_allocation(struct btrfs_fs_info *info)
3232 struct list_head *head = &info->space_info;
3233 struct btrfs_space_info *found;
3236 list_for_each_entry_rcu(found, head, list) {
3237 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3238 found->force_alloc = 1;
3243 static int should_alloc_chunk(struct btrfs_root *root,
3244 struct btrfs_space_info *sinfo, u64 alloc_bytes)
3246 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3249 if (sinfo->bytes_used + sinfo->bytes_reserved +
3250 alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3253 if (sinfo->bytes_used + sinfo->bytes_reserved +
3254 alloc_bytes < div_factor(num_bytes, 8))
3257 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3258 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3260 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3266 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3267 struct btrfs_root *extent_root, u64 alloc_bytes,
3268 u64 flags, int force)
3270 struct btrfs_space_info *space_info;
3271 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3274 mutex_lock(&fs_info->chunk_mutex);
3276 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3278 space_info = __find_space_info(extent_root->fs_info, flags);
3280 ret = update_space_info(extent_root->fs_info, flags,
3284 BUG_ON(!space_info);
3286 spin_lock(&space_info->lock);
3287 if (space_info->force_alloc)
3289 if (space_info->full) {
3290 spin_unlock(&space_info->lock);
3294 if (!force && !should_alloc_chunk(extent_root, space_info,
3296 spin_unlock(&space_info->lock);
3299 spin_unlock(&space_info->lock);
3302 * If we have mixed data/metadata chunks we want to make sure we keep
3303 * allocating mixed chunks instead of individual chunks.
3305 if (btrfs_mixed_space_info(space_info))
3306 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3309 * if we're doing a data chunk, go ahead and make sure that
3310 * we keep a reasonable number of metadata chunks allocated in the
3313 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3314 fs_info->data_chunk_allocations++;
3315 if (!(fs_info->data_chunk_allocations %
3316 fs_info->metadata_ratio))
3317 force_metadata_allocation(fs_info);
3320 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3321 spin_lock(&space_info->lock);
3323 space_info->full = 1;
3326 space_info->force_alloc = 0;
3327 spin_unlock(&space_info->lock);
3329 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3334 * shrink metadata reservation for delalloc
3336 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3337 struct btrfs_root *root, u64 to_reclaim, int sync)
3339 struct btrfs_block_rsv *block_rsv;
3340 struct btrfs_space_info *space_info;
3345 int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3347 unsigned long progress;
3349 block_rsv = &root->fs_info->delalloc_block_rsv;
3350 space_info = block_rsv->space_info;
3353 reserved = space_info->bytes_reserved;
3354 progress = space_info->reservation_progress;
3359 max_reclaim = min(reserved, to_reclaim);
3361 while (loops < 1024) {
3362 /* have the flusher threads jump in and do some IO */
3364 nr_pages = min_t(unsigned long, nr_pages,
3365 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3366 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3368 spin_lock(&space_info->lock);
3369 if (reserved > space_info->bytes_reserved)
3370 reclaimed += reserved - space_info->bytes_reserved;
3371 reserved = space_info->bytes_reserved;
3372 spin_unlock(&space_info->lock);
3376 if (reserved == 0 || reclaimed >= max_reclaim)
3379 if (trans && trans->transaction->blocked)
3382 time_left = schedule_timeout_interruptible(1);
3384 /* We were interrupted, exit */
3388 /* we've kicked the IO a few times, if anything has been freed,
3389 * exit. There is no sense in looping here for a long time
3390 * when we really need to commit the transaction, or there are
3391 * just too many writers without enough free space
3396 if (progress != space_info->reservation_progress)
3401 return reclaimed >= to_reclaim;
3405 * Retries tells us how many times we've called reserve_metadata_bytes. The
3406 * idea is if this is the first call (retries == 0) then we will add to our
3407 * reserved count if we can't make the allocation in order to hold our place
3408 * while we go and try and free up space. That way for retries > 1 we don't try
3409 * and add space, we just check to see if the amount of unused space is >= the
3410 * total space, meaning that our reservation is valid.
3412 * However if we don't intend to retry this reservation, pass -1 as retries so
3413 * that it short circuits this logic.
3415 static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
3416 struct btrfs_root *root,
3417 struct btrfs_block_rsv *block_rsv,
3418 u64 orig_bytes, int flush)
3420 struct btrfs_space_info *space_info = block_rsv->space_info;
3422 u64 num_bytes = orig_bytes;
3425 bool reserved = false;
3426 bool committed = false;
3433 spin_lock(&space_info->lock);
3434 unused = space_info->bytes_used + space_info->bytes_reserved +
3435 space_info->bytes_pinned + space_info->bytes_readonly +
3436 space_info->bytes_may_use;
3439 * The idea here is that we've not already over-reserved the block group
3440 * then we can go ahead and save our reservation first and then start
3441 * flushing if we need to. Otherwise if we've already overcommitted
3442 * lets start flushing stuff first and then come back and try to make
3445 if (unused <= space_info->total_bytes) {
3446 unused = space_info->total_bytes - unused;
3447 if (unused >= num_bytes) {
3449 space_info->bytes_reserved += orig_bytes;
3453 * Ok set num_bytes to orig_bytes since we aren't
3454 * overocmmitted, this way we only try and reclaim what
3457 num_bytes = orig_bytes;
3461 * Ok we're over committed, set num_bytes to the overcommitted
3462 * amount plus the amount of bytes that we need for this
3465 num_bytes = unused - space_info->total_bytes +
3466 (orig_bytes * (retries + 1));
3470 * Couldn't make our reservation, save our place so while we're trying
3471 * to reclaim space we can actually use it instead of somebody else
3472 * stealing it from us.
3474 if (ret && !reserved) {
3475 space_info->bytes_reserved += orig_bytes;
3479 spin_unlock(&space_info->lock);
3488 * We do synchronous shrinking since we don't actually unreserve
3489 * metadata until after the IO is completed.
3491 ret = shrink_delalloc(trans, root, num_bytes, 1);
3498 * So if we were overcommitted it's possible that somebody else flushed
3499 * out enough space and we simply didn't have enough space to reclaim,
3500 * so go back around and try again.
3507 spin_lock(&space_info->lock);
3509 * Not enough space to be reclaimed, don't bother committing the
3512 if (space_info->bytes_pinned < orig_bytes)
3514 spin_unlock(&space_info->lock);
3519 if (trans || committed)
3523 trans = btrfs_join_transaction(root, 1);
3526 ret = btrfs_commit_transaction(trans, root);
3535 spin_lock(&space_info->lock);
3536 space_info->bytes_reserved -= orig_bytes;
3537 spin_unlock(&space_info->lock);
3543 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3544 struct btrfs_root *root)
3546 struct btrfs_block_rsv *block_rsv;
3548 block_rsv = trans->block_rsv;
3550 block_rsv = root->block_rsv;
3553 block_rsv = &root->fs_info->empty_block_rsv;
3558 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3562 spin_lock(&block_rsv->lock);
3563 if (block_rsv->reserved >= num_bytes) {
3564 block_rsv->reserved -= num_bytes;
3565 if (block_rsv->reserved < block_rsv->size)
3566 block_rsv->full = 0;
3569 spin_unlock(&block_rsv->lock);
3573 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3574 u64 num_bytes, int update_size)
3576 spin_lock(&block_rsv->lock);
3577 block_rsv->reserved += num_bytes;
3579 block_rsv->size += num_bytes;
3580 else if (block_rsv->reserved >= block_rsv->size)
3581 block_rsv->full = 1;
3582 spin_unlock(&block_rsv->lock);
3585 void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3586 struct btrfs_block_rsv *dest, u64 num_bytes)
3588 struct btrfs_space_info *space_info = block_rsv->space_info;
3590 spin_lock(&block_rsv->lock);
3591 if (num_bytes == (u64)-1)
3592 num_bytes = block_rsv->size;
3593 block_rsv->size -= num_bytes;
3594 if (block_rsv->reserved >= block_rsv->size) {
3595 num_bytes = block_rsv->reserved - block_rsv->size;
3596 block_rsv->reserved = block_rsv->size;
3597 block_rsv->full = 1;
3601 spin_unlock(&block_rsv->lock);
3603 if (num_bytes > 0) {
3605 spin_lock(&dest->lock);
3609 bytes_to_add = dest->size - dest->reserved;
3610 bytes_to_add = min(num_bytes, bytes_to_add);
3611 dest->reserved += bytes_to_add;
3612 if (dest->reserved >= dest->size)
3614 num_bytes -= bytes_to_add;
3616 spin_unlock(&dest->lock);
3619 spin_lock(&space_info->lock);
3620 space_info->bytes_reserved -= num_bytes;
3621 space_info->reservation_progress++;
3622 spin_unlock(&space_info->lock);
3627 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3628 struct btrfs_block_rsv *dst, u64 num_bytes)
3632 ret = block_rsv_use_bytes(src, num_bytes);
3636 block_rsv_add_bytes(dst, num_bytes, 1);
3640 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3642 memset(rsv, 0, sizeof(*rsv));
3643 spin_lock_init(&rsv->lock);
3644 atomic_set(&rsv->usage, 1);
3646 INIT_LIST_HEAD(&rsv->list);
3649 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3651 struct btrfs_block_rsv *block_rsv;
3652 struct btrfs_fs_info *fs_info = root->fs_info;
3654 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3658 btrfs_init_block_rsv(block_rsv);
3659 block_rsv->space_info = __find_space_info(fs_info,
3660 BTRFS_BLOCK_GROUP_METADATA);
3664 void btrfs_free_block_rsv(struct btrfs_root *root,
3665 struct btrfs_block_rsv *rsv)
3667 if (rsv && atomic_dec_and_test(&rsv->usage)) {
3668 btrfs_block_rsv_release(root, rsv, (u64)-1);
3675 * make the block_rsv struct be able to capture freed space.
3676 * the captured space will re-add to the the block_rsv struct
3677 * after transaction commit
3679 void btrfs_add_durable_block_rsv(struct btrfs_fs_info *fs_info,
3680 struct btrfs_block_rsv *block_rsv)
3682 block_rsv->durable = 1;
3683 mutex_lock(&fs_info->durable_block_rsv_mutex);
3684 list_add_tail(&block_rsv->list, &fs_info->durable_block_rsv_list);
3685 mutex_unlock(&fs_info->durable_block_rsv_mutex);
3688 int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
3689 struct btrfs_root *root,
3690 struct btrfs_block_rsv *block_rsv,
3698 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
3700 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3707 int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
3708 struct btrfs_root *root,
3709 struct btrfs_block_rsv *block_rsv,
3710 u64 min_reserved, int min_factor)
3713 int commit_trans = 0;
3719 spin_lock(&block_rsv->lock);
3721 num_bytes = div_factor(block_rsv->size, min_factor);
3722 if (min_reserved > num_bytes)
3723 num_bytes = min_reserved;
3725 if (block_rsv->reserved >= num_bytes) {
3728 num_bytes -= block_rsv->reserved;
3729 if (block_rsv->durable &&
3730 block_rsv->freed[0] + block_rsv->freed[1] >= num_bytes)
3733 spin_unlock(&block_rsv->lock);
3737 if (block_rsv->refill_used) {
3738 ret = reserve_metadata_bytes(trans, root, block_rsv,
3741 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3750 trans = btrfs_join_transaction(root, 1);
3751 BUG_ON(IS_ERR(trans));
3752 ret = btrfs_commit_transaction(trans, root);
3759 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3760 struct btrfs_block_rsv *dst_rsv,
3763 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3766 void btrfs_block_rsv_release(struct btrfs_root *root,
3767 struct btrfs_block_rsv *block_rsv,
3770 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3771 if (global_rsv->full || global_rsv == block_rsv ||
3772 block_rsv->space_info != global_rsv->space_info)
3774 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3778 * helper to calculate size of global block reservation.
3779 * the desired value is sum of space used by extent tree,
3780 * checksum tree and root tree
3782 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3784 struct btrfs_space_info *sinfo;
3788 int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
3791 * per tree used space accounting can be inaccuracy, so we
3794 spin_lock(&fs_info->extent_root->accounting_lock);
3795 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item);
3796 spin_unlock(&fs_info->extent_root->accounting_lock);
3798 spin_lock(&fs_info->csum_root->accounting_lock);
3799 num_bytes += btrfs_root_used(&fs_info->csum_root->root_item);
3800 spin_unlock(&fs_info->csum_root->accounting_lock);
3802 spin_lock(&fs_info->tree_root->accounting_lock);
3803 num_bytes += btrfs_root_used(&fs_info->tree_root->root_item);
3804 spin_unlock(&fs_info->tree_root->accounting_lock);
3806 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3807 spin_lock(&sinfo->lock);
3808 data_used = sinfo->bytes_used;
3809 spin_unlock(&sinfo->lock);
3811 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3812 spin_lock(&sinfo->lock);
3813 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3815 meta_used = sinfo->bytes_used;
3816 spin_unlock(&sinfo->lock);
3818 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3820 num_bytes += div64_u64(data_used + meta_used, 50);
3822 if (num_bytes * 3 > meta_used)
3823 num_bytes = div64_u64(meta_used, 3);
3825 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3828 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3830 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3831 struct btrfs_space_info *sinfo = block_rsv->space_info;
3834 num_bytes = calc_global_metadata_size(fs_info);
3836 spin_lock(&block_rsv->lock);
3837 spin_lock(&sinfo->lock);
3839 block_rsv->size = num_bytes;
3841 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3842 sinfo->bytes_reserved + sinfo->bytes_readonly +
3843 sinfo->bytes_may_use;
3845 if (sinfo->total_bytes > num_bytes) {
3846 num_bytes = sinfo->total_bytes - num_bytes;
3847 block_rsv->reserved += num_bytes;
3848 sinfo->bytes_reserved += num_bytes;
3851 if (block_rsv->reserved >= block_rsv->size) {
3852 num_bytes = block_rsv->reserved - block_rsv->size;
3853 sinfo->bytes_reserved -= num_bytes;
3854 sinfo->reservation_progress++;
3855 block_rsv->reserved = block_rsv->size;
3856 block_rsv->full = 1;
3859 printk(KERN_INFO"global block rsv size %llu reserved %llu\n",
3860 block_rsv->size, block_rsv->reserved);
3862 spin_unlock(&sinfo->lock);
3863 spin_unlock(&block_rsv->lock);
3866 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3868 struct btrfs_space_info *space_info;
3870 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3871 fs_info->chunk_block_rsv.space_info = space_info;
3872 fs_info->chunk_block_rsv.priority = 10;
3874 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3875 fs_info->global_block_rsv.space_info = space_info;
3876 fs_info->global_block_rsv.priority = 10;
3877 fs_info->global_block_rsv.refill_used = 1;
3878 fs_info->delalloc_block_rsv.space_info = space_info;
3879 fs_info->trans_block_rsv.space_info = space_info;
3880 fs_info->empty_block_rsv.space_info = space_info;
3881 fs_info->empty_block_rsv.priority = 10;
3883 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3884 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3885 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3886 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3887 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3889 btrfs_add_durable_block_rsv(fs_info, &fs_info->global_block_rsv);
3891 btrfs_add_durable_block_rsv(fs_info, &fs_info->delalloc_block_rsv);
3893 update_global_block_rsv(fs_info);
3896 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3898 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3899 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3900 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3901 WARN_ON(fs_info->trans_block_rsv.size > 0);
3902 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3903 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3904 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3907 static u64 calc_trans_metadata_size(struct btrfs_root *root, int num_items)
3909 return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3913 int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans,
3914 struct btrfs_root *root,
3920 if (num_items == 0 || root->fs_info->chunk_root == root)
3923 num_bytes = calc_trans_metadata_size(root, num_items);
3924 ret = btrfs_block_rsv_add(trans, root, &root->fs_info->trans_block_rsv,
3927 trans->bytes_reserved += num_bytes;
3928 trans->block_rsv = &root->fs_info->trans_block_rsv;
3933 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3934 struct btrfs_root *root)
3936 if (!trans->bytes_reserved)
3939 BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv);
3940 btrfs_block_rsv_release(root, trans->block_rsv,
3941 trans->bytes_reserved);
3942 trans->bytes_reserved = 0;
3945 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3946 struct inode *inode)
3948 struct btrfs_root *root = BTRFS_I(inode)->root;
3949 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3950 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3953 * one for deleting orphan item, one for updating inode and
3954 * two for calling btrfs_truncate_inode_items.
3956 * btrfs_truncate_inode_items is a delete operation, it frees
3957 * more space than it uses in most cases. So two units of
3958 * metadata space should be enough for calling it many times.
3959 * If all of the metadata space is used, we can commit
3960 * transaction and use space it freed.
3962 u64 num_bytes = calc_trans_metadata_size(root, 4);
3963 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3966 void btrfs_orphan_release_metadata(struct inode *inode)
3968 struct btrfs_root *root = BTRFS_I(inode)->root;
3969 u64 num_bytes = calc_trans_metadata_size(root, 4);
3970 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3973 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3974 struct btrfs_pending_snapshot *pending)
3976 struct btrfs_root *root = pending->root;
3977 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3978 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3980 * two for root back/forward refs, two for directory entries
3981 * and one for root of the snapshot.
3983 u64 num_bytes = calc_trans_metadata_size(root, 5);
3984 dst_rsv->space_info = src_rsv->space_info;
3985 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3988 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
3990 return num_bytes >>= 3;
3993 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
3995 struct btrfs_root *root = BTRFS_I(inode)->root;
3996 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
3999 int reserved_extents;
4002 if (btrfs_transaction_in_commit(root->fs_info))
4003 schedule_timeout(1);
4005 num_bytes = ALIGN(num_bytes, root->sectorsize);
4007 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
4008 reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents);
4010 if (nr_extents > reserved_extents) {
4011 nr_extents -= reserved_extents;
4012 to_reserve = calc_trans_metadata_size(root, nr_extents);
4018 to_reserve += calc_csum_metadata_size(inode, num_bytes);
4019 ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
4023 atomic_add(nr_extents, &BTRFS_I(inode)->reserved_extents);
4024 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
4026 block_rsv_add_bytes(block_rsv, to_reserve, 1);
4028 if (block_rsv->size > 512 * 1024 * 1024)
4029 shrink_delalloc(NULL, root, to_reserve, 0);
4034 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4036 struct btrfs_root *root = BTRFS_I(inode)->root;
4039 int reserved_extents;
4041 num_bytes = ALIGN(num_bytes, root->sectorsize);
4042 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
4043 WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents) < 0);
4045 reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents);
4049 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
4050 if (nr_extents >= reserved_extents) {
4054 old = reserved_extents;
4055 nr_extents = reserved_extents - nr_extents;
4056 new = reserved_extents - nr_extents;
4057 old = atomic_cmpxchg(&BTRFS_I(inode)->reserved_extents,
4058 reserved_extents, new);
4059 if (likely(old == reserved_extents))
4061 reserved_extents = old;
4064 to_free = calc_csum_metadata_size(inode, num_bytes);
4066 to_free += calc_trans_metadata_size(root, nr_extents);
4068 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4072 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4076 ret = btrfs_check_data_free_space(inode, num_bytes);
4080 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4082 btrfs_free_reserved_data_space(inode, num_bytes);
4089 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4091 btrfs_delalloc_release_metadata(inode, num_bytes);
4092 btrfs_free_reserved_data_space(inode, num_bytes);
4095 static int update_block_group(struct btrfs_trans_handle *trans,
4096 struct btrfs_root *root,
4097 u64 bytenr, u64 num_bytes, int alloc)
4099 struct btrfs_block_group_cache *cache = NULL;
4100 struct btrfs_fs_info *info = root->fs_info;
4101 u64 total = num_bytes;
4106 /* block accounting for super block */
4107 spin_lock(&info->delalloc_lock);
4108 old_val = btrfs_super_bytes_used(&info->super_copy);
4110 old_val += num_bytes;
4112 old_val -= num_bytes;
4113 btrfs_set_super_bytes_used(&info->super_copy, old_val);
4114 spin_unlock(&info->delalloc_lock);
4117 cache = btrfs_lookup_block_group(info, bytenr);
4120 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4121 BTRFS_BLOCK_GROUP_RAID1 |
4122 BTRFS_BLOCK_GROUP_RAID10))
4127 * If this block group has free space cache written out, we
4128 * need to make sure to load it if we are removing space. This
4129 * is because we need the unpinning stage to actually add the
4130 * space back to the block group, otherwise we will leak space.
4132 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4133 cache_block_group(cache, trans, NULL, 1);
4135 byte_in_group = bytenr - cache->key.objectid;
4136 WARN_ON(byte_in_group > cache->key.offset);
4138 spin_lock(&cache->space_info->lock);
4139 spin_lock(&cache->lock);
4141 if (btrfs_super_cache_generation(&info->super_copy) != 0 &&
4142 cache->disk_cache_state < BTRFS_DC_CLEAR)
4143 cache->disk_cache_state = BTRFS_DC_CLEAR;
4146 old_val = btrfs_block_group_used(&cache->item);
4147 num_bytes = min(total, cache->key.offset - byte_in_group);
4149 old_val += num_bytes;
4150 btrfs_set_block_group_used(&cache->item, old_val);
4151 cache->reserved -= num_bytes;
4152 cache->space_info->bytes_reserved -= num_bytes;
4153 cache->space_info->reservation_progress++;
4154 cache->space_info->bytes_used += num_bytes;
4155 cache->space_info->disk_used += num_bytes * factor;
4156 spin_unlock(&cache->lock);
4157 spin_unlock(&cache->space_info->lock);
4159 old_val -= num_bytes;
4160 btrfs_set_block_group_used(&cache->item, old_val);
4161 cache->pinned += num_bytes;
4162 cache->space_info->bytes_pinned += num_bytes;
4163 cache->space_info->bytes_used -= num_bytes;
4164 cache->space_info->disk_used -= num_bytes * factor;
4165 spin_unlock(&cache->lock);
4166 spin_unlock(&cache->space_info->lock);
4168 set_extent_dirty(info->pinned_extents,
4169 bytenr, bytenr + num_bytes - 1,
4170 GFP_NOFS | __GFP_NOFAIL);
4172 btrfs_put_block_group(cache);
4174 bytenr += num_bytes;
4179 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4181 struct btrfs_block_group_cache *cache;
4184 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4188 bytenr = cache->key.objectid;
4189 btrfs_put_block_group(cache);
4194 static int pin_down_extent(struct btrfs_root *root,
4195 struct btrfs_block_group_cache *cache,
4196 u64 bytenr, u64 num_bytes, int reserved)
4198 spin_lock(&cache->space_info->lock);
4199 spin_lock(&cache->lock);
4200 cache->pinned += num_bytes;
4201 cache->space_info->bytes_pinned += num_bytes;
4203 cache->reserved -= num_bytes;
4204 cache->space_info->bytes_reserved -= num_bytes;
4205 cache->space_info->reservation_progress++;
4207 spin_unlock(&cache->lock);
4208 spin_unlock(&cache->space_info->lock);
4210 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4211 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4216 * this function must be called within transaction
4218 int btrfs_pin_extent(struct btrfs_root *root,
4219 u64 bytenr, u64 num_bytes, int reserved)
4221 struct btrfs_block_group_cache *cache;
4223 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4226 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4228 btrfs_put_block_group(cache);
4233 * update size of reserved extents. this function may return -EAGAIN
4234 * if 'reserve' is true or 'sinfo' is false.
4236 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
4237 u64 num_bytes, int reserve, int sinfo)
4241 struct btrfs_space_info *space_info = cache->space_info;
4242 spin_lock(&space_info->lock);
4243 spin_lock(&cache->lock);
4248 cache->reserved += num_bytes;
4249 space_info->bytes_reserved += num_bytes;
4253 space_info->bytes_readonly += num_bytes;
4254 cache->reserved -= num_bytes;
4255 space_info->bytes_reserved -= num_bytes;
4256 space_info->reservation_progress++;
4258 spin_unlock(&cache->lock);
4259 spin_unlock(&space_info->lock);
4261 spin_lock(&cache->lock);
4266 cache->reserved += num_bytes;
4268 cache->reserved -= num_bytes;
4270 spin_unlock(&cache->lock);
4275 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4276 struct btrfs_root *root)
4278 struct btrfs_fs_info *fs_info = root->fs_info;
4279 struct btrfs_caching_control *next;
4280 struct btrfs_caching_control *caching_ctl;
4281 struct btrfs_block_group_cache *cache;
4283 down_write(&fs_info->extent_commit_sem);
4285 list_for_each_entry_safe(caching_ctl, next,
4286 &fs_info->caching_block_groups, list) {
4287 cache = caching_ctl->block_group;
4288 if (block_group_cache_done(cache)) {
4289 cache->last_byte_to_unpin = (u64)-1;
4290 list_del_init(&caching_ctl->list);
4291 put_caching_control(caching_ctl);
4293 cache->last_byte_to_unpin = caching_ctl->progress;
4297 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4298 fs_info->pinned_extents = &fs_info->freed_extents[1];
4300 fs_info->pinned_extents = &fs_info->freed_extents[0];
4302 up_write(&fs_info->extent_commit_sem);
4304 update_global_block_rsv(fs_info);
4308 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4310 struct btrfs_fs_info *fs_info = root->fs_info;
4311 struct btrfs_block_group_cache *cache = NULL;
4314 while (start <= end) {
4316 start >= cache->key.objectid + cache->key.offset) {
4318 btrfs_put_block_group(cache);
4319 cache = btrfs_lookup_block_group(fs_info, start);
4323 len = cache->key.objectid + cache->key.offset - start;
4324 len = min(len, end + 1 - start);
4326 if (start < cache->last_byte_to_unpin) {
4327 len = min(len, cache->last_byte_to_unpin - start);
4328 btrfs_add_free_space(cache, start, len);
4333 spin_lock(&cache->space_info->lock);
4334 spin_lock(&cache->lock);
4335 cache->pinned -= len;
4336 cache->space_info->bytes_pinned -= len;
4338 cache->space_info->bytes_readonly += len;
4339 } else if (cache->reserved_pinned > 0) {
4340 len = min(len, cache->reserved_pinned);
4341 cache->reserved_pinned -= len;
4342 cache->space_info->bytes_reserved += len;
4344 spin_unlock(&cache->lock);
4345 spin_unlock(&cache->space_info->lock);
4349 btrfs_put_block_group(cache);
4353 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4354 struct btrfs_root *root)
4356 struct btrfs_fs_info *fs_info = root->fs_info;
4357 struct extent_io_tree *unpin;
4358 struct btrfs_block_rsv *block_rsv;
4359 struct btrfs_block_rsv *next_rsv;
4365 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4366 unpin = &fs_info->freed_extents[1];
4368 unpin = &fs_info->freed_extents[0];
4371 ret = find_first_extent_bit(unpin, 0, &start, &end,
4376 ret = btrfs_discard_extent(root, start, end + 1 - start);
4378 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4379 unpin_extent_range(root, start, end);
4383 mutex_lock(&fs_info->durable_block_rsv_mutex);
4384 list_for_each_entry_safe(block_rsv, next_rsv,
4385 &fs_info->durable_block_rsv_list, list) {
4387 idx = trans->transid & 0x1;
4388 if (block_rsv->freed[idx] > 0) {
4389 block_rsv_add_bytes(block_rsv,
4390 block_rsv->freed[idx], 0);
4391 block_rsv->freed[idx] = 0;
4393 if (atomic_read(&block_rsv->usage) == 0) {
4394 btrfs_block_rsv_release(root, block_rsv, (u64)-1);
4396 if (block_rsv->freed[0] == 0 &&
4397 block_rsv->freed[1] == 0) {
4398 list_del_init(&block_rsv->list);
4402 btrfs_block_rsv_release(root, block_rsv, 0);
4405 mutex_unlock(&fs_info->durable_block_rsv_mutex);
4410 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4411 struct btrfs_root *root,
4412 u64 bytenr, u64 num_bytes, u64 parent,
4413 u64 root_objectid, u64 owner_objectid,
4414 u64 owner_offset, int refs_to_drop,
4415 struct btrfs_delayed_extent_op *extent_op)
4417 struct btrfs_key key;
4418 struct btrfs_path *path;
4419 struct btrfs_fs_info *info = root->fs_info;
4420 struct btrfs_root *extent_root = info->extent_root;
4421 struct extent_buffer *leaf;
4422 struct btrfs_extent_item *ei;
4423 struct btrfs_extent_inline_ref *iref;
4426 int extent_slot = 0;
4427 int found_extent = 0;
4432 path = btrfs_alloc_path();
4437 path->leave_spinning = 1;
4439 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4440 BUG_ON(!is_data && refs_to_drop != 1);
4442 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4443 bytenr, num_bytes, parent,
4444 root_objectid, owner_objectid,
4447 extent_slot = path->slots[0];
4448 while (extent_slot >= 0) {
4449 btrfs_item_key_to_cpu(path->nodes[0], &key,
4451 if (key.objectid != bytenr)
4453 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4454 key.offset == num_bytes) {
4458 if (path->slots[0] - extent_slot > 5)
4462 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4463 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4464 if (found_extent && item_size < sizeof(*ei))
4467 if (!found_extent) {
4469 ret = remove_extent_backref(trans, extent_root, path,
4473 btrfs_release_path(extent_root, path);
4474 path->leave_spinning = 1;
4476 key.objectid = bytenr;
4477 key.type = BTRFS_EXTENT_ITEM_KEY;
4478 key.offset = num_bytes;
4480 ret = btrfs_search_slot(trans, extent_root,
4483 printk(KERN_ERR "umm, got %d back from search"
4484 ", was looking for %llu\n", ret,
4485 (unsigned long long)bytenr);
4486 btrfs_print_leaf(extent_root, path->nodes[0]);
4489 extent_slot = path->slots[0];
4492 btrfs_print_leaf(extent_root, path->nodes[0]);
4494 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4495 "parent %llu root %llu owner %llu offset %llu\n",
4496 (unsigned long long)bytenr,
4497 (unsigned long long)parent,
4498 (unsigned long long)root_objectid,
4499 (unsigned long long)owner_objectid,
4500 (unsigned long long)owner_offset);
4503 leaf = path->nodes[0];
4504 item_size = btrfs_item_size_nr(leaf, extent_slot);
4505 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4506 if (item_size < sizeof(*ei)) {
4507 BUG_ON(found_extent || extent_slot != path->slots[0]);
4508 ret = convert_extent_item_v0(trans, extent_root, path,
4512 btrfs_release_path(extent_root, path);
4513 path->leave_spinning = 1;
4515 key.objectid = bytenr;
4516 key.type = BTRFS_EXTENT_ITEM_KEY;
4517 key.offset = num_bytes;
4519 ret = btrfs_search_slot(trans, extent_root, &key, path,
4522 printk(KERN_ERR "umm, got %d back from search"
4523 ", was looking for %llu\n", ret,
4524 (unsigned long long)bytenr);
4525 btrfs_print_leaf(extent_root, path->nodes[0]);
4528 extent_slot = path->slots[0];
4529 leaf = path->nodes[0];
4530 item_size = btrfs_item_size_nr(leaf, extent_slot);
4533 BUG_ON(item_size < sizeof(*ei));
4534 ei = btrfs_item_ptr(leaf, extent_slot,
4535 struct btrfs_extent_item);
4536 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4537 struct btrfs_tree_block_info *bi;
4538 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4539 bi = (struct btrfs_tree_block_info *)(ei + 1);
4540 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4543 refs = btrfs_extent_refs(leaf, ei);
4544 BUG_ON(refs < refs_to_drop);
4545 refs -= refs_to_drop;
4549 __run_delayed_extent_op(extent_op, leaf, ei);
4551 * In the case of inline back ref, reference count will
4552 * be updated by remove_extent_backref
4555 BUG_ON(!found_extent);
4557 btrfs_set_extent_refs(leaf, ei, refs);
4558 btrfs_mark_buffer_dirty(leaf);
4561 ret = remove_extent_backref(trans, extent_root, path,
4568 BUG_ON(is_data && refs_to_drop !=
4569 extent_data_ref_count(root, path, iref));
4571 BUG_ON(path->slots[0] != extent_slot);
4573 BUG_ON(path->slots[0] != extent_slot + 1);
4574 path->slots[0] = extent_slot;
4579 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4582 btrfs_release_path(extent_root, path);
4585 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4588 invalidate_mapping_pages(info->btree_inode->i_mapping,
4589 bytenr >> PAGE_CACHE_SHIFT,
4590 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4593 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4596 btrfs_free_path(path);
4601 * when we free an block, it is possible (and likely) that we free the last
4602 * delayed ref for that extent as well. This searches the delayed ref tree for
4603 * a given extent, and if there are no other delayed refs to be processed, it
4604 * removes it from the tree.
4606 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4607 struct btrfs_root *root, u64 bytenr)
4609 struct btrfs_delayed_ref_head *head;
4610 struct btrfs_delayed_ref_root *delayed_refs;
4611 struct btrfs_delayed_ref_node *ref;
4612 struct rb_node *node;
4615 delayed_refs = &trans->transaction->delayed_refs;
4616 spin_lock(&delayed_refs->lock);
4617 head = btrfs_find_delayed_ref_head(trans, bytenr);
4621 node = rb_prev(&head->node.rb_node);
4625 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4627 /* there are still entries for this ref, we can't drop it */
4628 if (ref->bytenr == bytenr)
4631 if (head->extent_op) {
4632 if (!head->must_insert_reserved)
4634 kfree(head->extent_op);
4635 head->extent_op = NULL;
4639 * waiting for the lock here would deadlock. If someone else has it
4640 * locked they are already in the process of dropping it anyway
4642 if (!mutex_trylock(&head->mutex))
4646 * at this point we have a head with no other entries. Go
4647 * ahead and process it.
4649 head->node.in_tree = 0;
4650 rb_erase(&head->node.rb_node, &delayed_refs->root);
4652 delayed_refs->num_entries--;
4655 * we don't take a ref on the node because we're removing it from the
4656 * tree, so we just steal the ref the tree was holding.
4658 delayed_refs->num_heads--;
4659 if (list_empty(&head->cluster))
4660 delayed_refs->num_heads_ready--;
4662 list_del_init(&head->cluster);
4663 spin_unlock(&delayed_refs->lock);
4665 BUG_ON(head->extent_op);
4666 if (head->must_insert_reserved)
4669 mutex_unlock(&head->mutex);
4670 btrfs_put_delayed_ref(&head->node);
4673 spin_unlock(&delayed_refs->lock);
4677 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4678 struct btrfs_root *root,
4679 struct extent_buffer *buf,
4680 u64 parent, int last_ref)
4682 struct btrfs_block_rsv *block_rsv;
4683 struct btrfs_block_group_cache *cache = NULL;
4686 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4687 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4688 parent, root->root_key.objectid,
4689 btrfs_header_level(buf),
4690 BTRFS_DROP_DELAYED_REF, NULL);
4697 block_rsv = get_block_rsv(trans, root);
4698 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4699 if (block_rsv->space_info != cache->space_info)
4702 if (btrfs_header_generation(buf) == trans->transid) {
4703 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4704 ret = check_ref_cleanup(trans, root, buf->start);
4709 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4710 pin_down_extent(root, cache, buf->start, buf->len, 1);
4714 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4716 btrfs_add_free_space(cache, buf->start, buf->len);
4717 ret = update_reserved_bytes(cache, buf->len, 0, 0);
4718 if (ret == -EAGAIN) {
4719 /* block group became read-only */
4720 update_reserved_bytes(cache, buf->len, 0, 1);
4725 spin_lock(&block_rsv->lock);
4726 if (block_rsv->reserved < block_rsv->size) {
4727 block_rsv->reserved += buf->len;
4730 spin_unlock(&block_rsv->lock);
4733 spin_lock(&cache->space_info->lock);
4734 cache->space_info->bytes_reserved -= buf->len;
4735 cache->space_info->reservation_progress++;
4736 spin_unlock(&cache->space_info->lock);
4741 if (block_rsv->durable && !cache->ro) {
4743 spin_lock(&cache->lock);
4745 cache->reserved_pinned += buf->len;
4748 spin_unlock(&cache->lock);
4751 spin_lock(&block_rsv->lock);
4752 block_rsv->freed[trans->transid & 0x1] += buf->len;
4753 spin_unlock(&block_rsv->lock);
4758 * Deleting the buffer, clear the corrupt flag since it doesn't matter
4761 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
4762 btrfs_put_block_group(cache);
4765 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4766 struct btrfs_root *root,
4767 u64 bytenr, u64 num_bytes, u64 parent,
4768 u64 root_objectid, u64 owner, u64 offset)
4773 * tree log blocks never actually go into the extent allocation
4774 * tree, just update pinning info and exit early.
4776 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4777 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4778 /* unlocks the pinned mutex */
4779 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4781 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4782 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4783 parent, root_objectid, (int)owner,
4784 BTRFS_DROP_DELAYED_REF, NULL);
4787 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4788 parent, root_objectid, owner,
4789 offset, BTRFS_DROP_DELAYED_REF, NULL);
4795 static u64 stripe_align(struct btrfs_root *root, u64 val)
4797 u64 mask = ((u64)root->stripesize - 1);
4798 u64 ret = (val + mask) & ~mask;
4803 * when we wait for progress in the block group caching, its because
4804 * our allocation attempt failed at least once. So, we must sleep
4805 * and let some progress happen before we try again.
4807 * This function will sleep at least once waiting for new free space to
4808 * show up, and then it will check the block group free space numbers
4809 * for our min num_bytes. Another option is to have it go ahead
4810 * and look in the rbtree for a free extent of a given size, but this
4814 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4817 struct btrfs_caching_control *caching_ctl;
4820 caching_ctl = get_caching_control(cache);
4824 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4825 (cache->free_space >= num_bytes));
4827 put_caching_control(caching_ctl);
4832 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4834 struct btrfs_caching_control *caching_ctl;
4837 caching_ctl = get_caching_control(cache);
4841 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4843 put_caching_control(caching_ctl);
4847 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4850 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4852 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4854 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4856 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4863 enum btrfs_loop_type {
4864 LOOP_FIND_IDEAL = 0,
4865 LOOP_CACHING_NOWAIT = 1,
4866 LOOP_CACHING_WAIT = 2,
4867 LOOP_ALLOC_CHUNK = 3,
4868 LOOP_NO_EMPTY_SIZE = 4,
4872 * walks the btree of allocated extents and find a hole of a given size.
4873 * The key ins is changed to record the hole:
4874 * ins->objectid == block start
4875 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4876 * ins->offset == number of blocks
4877 * Any available blocks before search_start are skipped.
4879 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4880 struct btrfs_root *orig_root,
4881 u64 num_bytes, u64 empty_size,
4882 u64 search_start, u64 search_end,
4883 u64 hint_byte, struct btrfs_key *ins,
4887 struct btrfs_root *root = orig_root->fs_info->extent_root;
4888 struct btrfs_free_cluster *last_ptr = NULL;
4889 struct btrfs_block_group_cache *block_group = NULL;
4890 int empty_cluster = 2 * 1024 * 1024;
4891 int allowed_chunk_alloc = 0;
4892 int done_chunk_alloc = 0;
4893 struct btrfs_space_info *space_info;
4894 int last_ptr_loop = 0;
4897 bool found_uncached_bg = false;
4898 bool failed_cluster_refill = false;
4899 bool failed_alloc = false;
4900 bool use_cluster = true;
4901 u64 ideal_cache_percent = 0;
4902 u64 ideal_cache_offset = 0;
4904 WARN_ON(num_bytes < root->sectorsize);
4905 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4909 space_info = __find_space_info(root->fs_info, data);
4911 printk(KERN_ERR "No space info for %d\n", data);
4916 * If the space info is for both data and metadata it means we have a
4917 * small filesystem and we can't use the clustering stuff.
4919 if (btrfs_mixed_space_info(space_info))
4920 use_cluster = false;
4922 if (orig_root->ref_cows || empty_size)
4923 allowed_chunk_alloc = 1;
4925 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
4926 last_ptr = &root->fs_info->meta_alloc_cluster;
4927 if (!btrfs_test_opt(root, SSD))
4928 empty_cluster = 64 * 1024;
4931 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
4932 btrfs_test_opt(root, SSD)) {
4933 last_ptr = &root->fs_info->data_alloc_cluster;
4937 spin_lock(&last_ptr->lock);
4938 if (last_ptr->block_group)
4939 hint_byte = last_ptr->window_start;
4940 spin_unlock(&last_ptr->lock);
4943 search_start = max(search_start, first_logical_byte(root, 0));
4944 search_start = max(search_start, hint_byte);
4949 if (search_start == hint_byte) {
4951 block_group = btrfs_lookup_block_group(root->fs_info,
4954 * we don't want to use the block group if it doesn't match our
4955 * allocation bits, or if its not cached.
4957 * However if we are re-searching with an ideal block group
4958 * picked out then we don't care that the block group is cached.
4960 if (block_group && block_group_bits(block_group, data) &&
4961 (block_group->cached != BTRFS_CACHE_NO ||
4962 search_start == ideal_cache_offset)) {
4963 down_read(&space_info->groups_sem);
4964 if (list_empty(&block_group->list) ||
4967 * someone is removing this block group,
4968 * we can't jump into the have_block_group
4969 * target because our list pointers are not
4972 btrfs_put_block_group(block_group);
4973 up_read(&space_info->groups_sem);
4975 index = get_block_group_index(block_group);
4976 goto have_block_group;
4978 } else if (block_group) {
4979 btrfs_put_block_group(block_group);
4983 down_read(&space_info->groups_sem);
4984 list_for_each_entry(block_group, &space_info->block_groups[index],
4989 btrfs_get_block_group(block_group);
4990 search_start = block_group->key.objectid;
4993 * this can happen if we end up cycling through all the
4994 * raid types, but we want to make sure we only allocate
4995 * for the proper type.
4997 if (!block_group_bits(block_group, data)) {
4998 u64 extra = BTRFS_BLOCK_GROUP_DUP |
4999 BTRFS_BLOCK_GROUP_RAID1 |
5000 BTRFS_BLOCK_GROUP_RAID10;
5003 * if they asked for extra copies and this block group
5004 * doesn't provide them, bail. This does allow us to
5005 * fill raid0 from raid1.
5007 if ((data & extra) && !(block_group->flags & extra))
5012 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
5015 ret = cache_block_group(block_group, trans,
5017 if (block_group->cached == BTRFS_CACHE_FINISHED)
5018 goto have_block_group;
5020 free_percent = btrfs_block_group_used(&block_group->item);
5021 free_percent *= 100;
5022 free_percent = div64_u64(free_percent,
5023 block_group->key.offset);
5024 free_percent = 100 - free_percent;
5025 if (free_percent > ideal_cache_percent &&
5026 likely(!block_group->ro)) {
5027 ideal_cache_offset = block_group->key.objectid;
5028 ideal_cache_percent = free_percent;
5032 * We only want to start kthread caching if we are at
5033 * the point where we will wait for caching to make
5034 * progress, or if our ideal search is over and we've
5035 * found somebody to start caching.
5037 if (loop > LOOP_CACHING_NOWAIT ||
5038 (loop > LOOP_FIND_IDEAL &&
5039 atomic_read(&space_info->caching_threads) < 2)) {
5040 ret = cache_block_group(block_group, trans,
5044 found_uncached_bg = true;
5047 * If loop is set for cached only, try the next block
5050 if (loop == LOOP_FIND_IDEAL)
5054 cached = block_group_cache_done(block_group);
5055 if (unlikely(!cached))
5056 found_uncached_bg = true;
5058 if (unlikely(block_group->ro))
5062 * Ok we want to try and use the cluster allocator, so lets look
5063 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
5064 * have tried the cluster allocator plenty of times at this
5065 * point and not have found anything, so we are likely way too
5066 * fragmented for the clustering stuff to find anything, so lets
5067 * just skip it and let the allocator find whatever block it can
5070 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
5072 * the refill lock keeps out other
5073 * people trying to start a new cluster
5075 spin_lock(&last_ptr->refill_lock);
5076 if (last_ptr->block_group &&
5077 (last_ptr->block_group->ro ||
5078 !block_group_bits(last_ptr->block_group, data))) {
5080 goto refill_cluster;
5083 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5084 num_bytes, search_start);
5086 /* we have a block, we're done */
5087 spin_unlock(&last_ptr->refill_lock);
5091 spin_lock(&last_ptr->lock);
5093 * whoops, this cluster doesn't actually point to
5094 * this block group. Get a ref on the block
5095 * group is does point to and try again
5097 if (!last_ptr_loop && last_ptr->block_group &&
5098 last_ptr->block_group != block_group) {
5100 btrfs_put_block_group(block_group);
5101 block_group = last_ptr->block_group;
5102 btrfs_get_block_group(block_group);
5103 spin_unlock(&last_ptr->lock);
5104 spin_unlock(&last_ptr->refill_lock);
5107 search_start = block_group->key.objectid;
5109 * we know this block group is properly
5110 * in the list because
5111 * btrfs_remove_block_group, drops the
5112 * cluster before it removes the block
5113 * group from the list
5115 goto have_block_group;
5117 spin_unlock(&last_ptr->lock);
5120 * this cluster didn't work out, free it and
5123 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5127 /* allocate a cluster in this block group */
5128 ret = btrfs_find_space_cluster(trans, root,
5129 block_group, last_ptr,
5131 empty_cluster + empty_size);
5134 * now pull our allocation out of this
5137 offset = btrfs_alloc_from_cluster(block_group,
5138 last_ptr, num_bytes,
5141 /* we found one, proceed */
5142 spin_unlock(&last_ptr->refill_lock);
5145 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5146 && !failed_cluster_refill) {
5147 spin_unlock(&last_ptr->refill_lock);
5149 failed_cluster_refill = true;
5150 wait_block_group_cache_progress(block_group,
5151 num_bytes + empty_cluster + empty_size);
5152 goto have_block_group;
5156 * at this point we either didn't find a cluster
5157 * or we weren't able to allocate a block from our
5158 * cluster. Free the cluster we've been trying
5159 * to use, and go to the next block group
5161 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5162 spin_unlock(&last_ptr->refill_lock);
5166 offset = btrfs_find_space_for_alloc(block_group, search_start,
5167 num_bytes, empty_size);
5169 * If we didn't find a chunk, and we haven't failed on this
5170 * block group before, and this block group is in the middle of
5171 * caching and we are ok with waiting, then go ahead and wait
5172 * for progress to be made, and set failed_alloc to true.
5174 * If failed_alloc is true then we've already waited on this
5175 * block group once and should move on to the next block group.
5177 if (!offset && !failed_alloc && !cached &&
5178 loop > LOOP_CACHING_NOWAIT) {
5179 wait_block_group_cache_progress(block_group,
5180 num_bytes + empty_size);
5181 failed_alloc = true;
5182 goto have_block_group;
5183 } else if (!offset) {
5187 search_start = stripe_align(root, offset);
5188 /* move on to the next group */
5189 if (search_start + num_bytes >= search_end) {
5190 btrfs_add_free_space(block_group, offset, num_bytes);
5194 /* move on to the next group */
5195 if (search_start + num_bytes >
5196 block_group->key.objectid + block_group->key.offset) {
5197 btrfs_add_free_space(block_group, offset, num_bytes);
5201 ins->objectid = search_start;
5202 ins->offset = num_bytes;
5204 if (offset < search_start)
5205 btrfs_add_free_space(block_group, offset,
5206 search_start - offset);
5207 BUG_ON(offset > search_start);
5209 ret = update_reserved_bytes(block_group, num_bytes, 1,
5210 (data & BTRFS_BLOCK_GROUP_DATA));
5211 if (ret == -EAGAIN) {
5212 btrfs_add_free_space(block_group, offset, num_bytes);
5216 /* we are all good, lets return */
5217 ins->objectid = search_start;
5218 ins->offset = num_bytes;
5220 if (offset < search_start)
5221 btrfs_add_free_space(block_group, offset,
5222 search_start - offset);
5223 BUG_ON(offset > search_start);
5226 failed_cluster_refill = false;
5227 failed_alloc = false;
5228 BUG_ON(index != get_block_group_index(block_group));
5229 btrfs_put_block_group(block_group);
5231 up_read(&space_info->groups_sem);
5233 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5236 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5237 * for them to make caching progress. Also
5238 * determine the best possible bg to cache
5239 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5240 * caching kthreads as we move along
5241 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5242 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5243 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5246 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE &&
5247 (found_uncached_bg || empty_size || empty_cluster ||
5248 allowed_chunk_alloc)) {
5250 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5251 found_uncached_bg = false;
5253 if (!ideal_cache_percent &&
5254 atomic_read(&space_info->caching_threads))
5258 * 1 of the following 2 things have happened so far
5260 * 1) We found an ideal block group for caching that
5261 * is mostly full and will cache quickly, so we might
5262 * as well wait for it.
5264 * 2) We searched for cached only and we didn't find
5265 * anything, and we didn't start any caching kthreads
5266 * either, so chances are we will loop through and
5267 * start a couple caching kthreads, and then come back
5268 * around and just wait for them. This will be slower
5269 * because we will have 2 caching kthreads reading at
5270 * the same time when we could have just started one
5271 * and waited for it to get far enough to give us an
5272 * allocation, so go ahead and go to the wait caching
5275 loop = LOOP_CACHING_WAIT;
5276 search_start = ideal_cache_offset;
5277 ideal_cache_percent = 0;
5279 } else if (loop == LOOP_FIND_IDEAL) {
5281 * Didn't find a uncached bg, wait on anything we find
5284 loop = LOOP_CACHING_WAIT;
5288 if (loop < LOOP_CACHING_WAIT) {
5293 if (loop == LOOP_ALLOC_CHUNK) {
5298 if (allowed_chunk_alloc) {
5299 ret = do_chunk_alloc(trans, root, num_bytes +
5300 2 * 1024 * 1024, data, 1);
5301 allowed_chunk_alloc = 0;
5302 done_chunk_alloc = 1;
5303 } else if (!done_chunk_alloc) {
5304 space_info->force_alloc = 1;
5307 if (loop < LOOP_NO_EMPTY_SIZE) {
5312 } else if (!ins->objectid) {
5316 /* we found what we needed */
5317 if (ins->objectid) {
5318 if (!(data & BTRFS_BLOCK_GROUP_DATA))
5319 trans->block_group = block_group->key.objectid;
5321 btrfs_put_block_group(block_group);
5328 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5329 int dump_block_groups)
5331 struct btrfs_block_group_cache *cache;
5334 spin_lock(&info->lock);
5335 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
5336 (unsigned long long)(info->total_bytes - info->bytes_used -
5337 info->bytes_pinned - info->bytes_reserved -
5338 info->bytes_readonly),
5339 (info->full) ? "" : "not ");
5340 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5341 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5342 (unsigned long long)info->total_bytes,
5343 (unsigned long long)info->bytes_used,
5344 (unsigned long long)info->bytes_pinned,
5345 (unsigned long long)info->bytes_reserved,
5346 (unsigned long long)info->bytes_may_use,
5347 (unsigned long long)info->bytes_readonly);
5348 spin_unlock(&info->lock);
5350 if (!dump_block_groups)
5353 down_read(&info->groups_sem);
5355 list_for_each_entry(cache, &info->block_groups[index], list) {
5356 spin_lock(&cache->lock);
5357 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5358 "%llu pinned %llu reserved\n",
5359 (unsigned long long)cache->key.objectid,
5360 (unsigned long long)cache->key.offset,
5361 (unsigned long long)btrfs_block_group_used(&cache->item),
5362 (unsigned long long)cache->pinned,
5363 (unsigned long long)cache->reserved);
5364 btrfs_dump_free_space(cache, bytes);
5365 spin_unlock(&cache->lock);
5367 if (++index < BTRFS_NR_RAID_TYPES)
5369 up_read(&info->groups_sem);
5372 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5373 struct btrfs_root *root,
5374 u64 num_bytes, u64 min_alloc_size,
5375 u64 empty_size, u64 hint_byte,
5376 u64 search_end, struct btrfs_key *ins,
5380 u64 search_start = 0;
5382 data = btrfs_get_alloc_profile(root, data);
5385 * the only place that sets empty_size is btrfs_realloc_node, which
5386 * is not called recursively on allocations
5388 if (empty_size || root->ref_cows)
5389 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5390 num_bytes + 2 * 1024 * 1024, data, 0);
5392 WARN_ON(num_bytes < root->sectorsize);
5393 ret = find_free_extent(trans, root, num_bytes, empty_size,
5394 search_start, search_end, hint_byte,
5397 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5398 num_bytes = num_bytes >> 1;
5399 num_bytes = num_bytes & ~(root->sectorsize - 1);
5400 num_bytes = max(num_bytes, min_alloc_size);
5401 do_chunk_alloc(trans, root->fs_info->extent_root,
5402 num_bytes, data, 1);
5405 if (ret == -ENOSPC && btrfs_test_opt(root, ENOSPC_DEBUG)) {
5406 struct btrfs_space_info *sinfo;
5408 sinfo = __find_space_info(root->fs_info, data);
5409 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5410 "wanted %llu\n", (unsigned long long)data,
5411 (unsigned long long)num_bytes);
5412 dump_space_info(sinfo, num_bytes, 1);
5415 trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
5420 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
5422 struct btrfs_block_group_cache *cache;
5425 cache = btrfs_lookup_block_group(root->fs_info, start);
5427 printk(KERN_ERR "Unable to find block group for %llu\n",
5428 (unsigned long long)start);
5432 ret = btrfs_discard_extent(root, start, len);
5434 btrfs_add_free_space(cache, start, len);
5435 update_reserved_bytes(cache, len, 0, 1);
5436 btrfs_put_block_group(cache);
5438 trace_btrfs_reserved_extent_free(root, start, len);
5443 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5444 struct btrfs_root *root,
5445 u64 parent, u64 root_objectid,
5446 u64 flags, u64 owner, u64 offset,
5447 struct btrfs_key *ins, int ref_mod)
5450 struct btrfs_fs_info *fs_info = root->fs_info;
5451 struct btrfs_extent_item *extent_item;
5452 struct btrfs_extent_inline_ref *iref;
5453 struct btrfs_path *path;
5454 struct extent_buffer *leaf;
5459 type = BTRFS_SHARED_DATA_REF_KEY;
5461 type = BTRFS_EXTENT_DATA_REF_KEY;
5463 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5465 path = btrfs_alloc_path();
5468 path->leave_spinning = 1;
5469 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5473 leaf = path->nodes[0];
5474 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5475 struct btrfs_extent_item);
5476 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5477 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5478 btrfs_set_extent_flags(leaf, extent_item,
5479 flags | BTRFS_EXTENT_FLAG_DATA);
5481 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5482 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5484 struct btrfs_shared_data_ref *ref;
5485 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5486 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5487 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5489 struct btrfs_extent_data_ref *ref;
5490 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5491 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5492 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5493 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5494 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5497 btrfs_mark_buffer_dirty(path->nodes[0]);
5498 btrfs_free_path(path);
5500 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5502 printk(KERN_ERR "btrfs update block group failed for %llu "
5503 "%llu\n", (unsigned long long)ins->objectid,
5504 (unsigned long long)ins->offset);
5510 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5511 struct btrfs_root *root,
5512 u64 parent, u64 root_objectid,
5513 u64 flags, struct btrfs_disk_key *key,
5514 int level, struct btrfs_key *ins)
5517 struct btrfs_fs_info *fs_info = root->fs_info;
5518 struct btrfs_extent_item *extent_item;
5519 struct btrfs_tree_block_info *block_info;
5520 struct btrfs_extent_inline_ref *iref;
5521 struct btrfs_path *path;
5522 struct extent_buffer *leaf;
5523 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5525 path = btrfs_alloc_path();
5528 path->leave_spinning = 1;
5529 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5533 leaf = path->nodes[0];
5534 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5535 struct btrfs_extent_item);
5536 btrfs_set_extent_refs(leaf, extent_item, 1);
5537 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5538 btrfs_set_extent_flags(leaf, extent_item,
5539 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5540 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5542 btrfs_set_tree_block_key(leaf, block_info, key);
5543 btrfs_set_tree_block_level(leaf, block_info, level);
5545 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5547 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5548 btrfs_set_extent_inline_ref_type(leaf, iref,
5549 BTRFS_SHARED_BLOCK_REF_KEY);
5550 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5552 btrfs_set_extent_inline_ref_type(leaf, iref,
5553 BTRFS_TREE_BLOCK_REF_KEY);
5554 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5557 btrfs_mark_buffer_dirty(leaf);
5558 btrfs_free_path(path);
5560 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5562 printk(KERN_ERR "btrfs update block group failed for %llu "
5563 "%llu\n", (unsigned long long)ins->objectid,
5564 (unsigned long long)ins->offset);
5570 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5571 struct btrfs_root *root,
5572 u64 root_objectid, u64 owner,
5573 u64 offset, struct btrfs_key *ins)
5577 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5579 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5580 0, root_objectid, owner, offset,
5581 BTRFS_ADD_DELAYED_EXTENT, NULL);
5586 * this is used by the tree logging recovery code. It records that
5587 * an extent has been allocated and makes sure to clear the free
5588 * space cache bits as well
5590 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5591 struct btrfs_root *root,
5592 u64 root_objectid, u64 owner, u64 offset,
5593 struct btrfs_key *ins)
5596 struct btrfs_block_group_cache *block_group;
5597 struct btrfs_caching_control *caching_ctl;
5598 u64 start = ins->objectid;
5599 u64 num_bytes = ins->offset;
5601 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5602 cache_block_group(block_group, trans, NULL, 0);
5603 caching_ctl = get_caching_control(block_group);
5606 BUG_ON(!block_group_cache_done(block_group));
5607 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5610 mutex_lock(&caching_ctl->mutex);
5612 if (start >= caching_ctl->progress) {
5613 ret = add_excluded_extent(root, start, num_bytes);
5615 } else if (start + num_bytes <= caching_ctl->progress) {
5616 ret = btrfs_remove_free_space(block_group,
5620 num_bytes = caching_ctl->progress - start;
5621 ret = btrfs_remove_free_space(block_group,
5625 start = caching_ctl->progress;
5626 num_bytes = ins->objectid + ins->offset -
5627 caching_ctl->progress;
5628 ret = add_excluded_extent(root, start, num_bytes);
5632 mutex_unlock(&caching_ctl->mutex);
5633 put_caching_control(caching_ctl);
5636 ret = update_reserved_bytes(block_group, ins->offset, 1, 1);
5638 btrfs_put_block_group(block_group);
5639 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5640 0, owner, offset, ins, 1);
5644 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5645 struct btrfs_root *root,
5646 u64 bytenr, u32 blocksize,
5649 struct extent_buffer *buf;
5651 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5653 return ERR_PTR(-ENOMEM);
5654 btrfs_set_header_generation(buf, trans->transid);
5655 btrfs_set_buffer_lockdep_class(buf, level);
5656 btrfs_tree_lock(buf);
5657 clean_tree_block(trans, root, buf);
5659 btrfs_set_lock_blocking(buf);
5660 btrfs_set_buffer_uptodate(buf);
5662 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5664 * we allow two log transactions at a time, use different
5665 * EXENT bit to differentiate dirty pages.
5667 if (root->log_transid % 2 == 0)
5668 set_extent_dirty(&root->dirty_log_pages, buf->start,
5669 buf->start + buf->len - 1, GFP_NOFS);
5671 set_extent_new(&root->dirty_log_pages, buf->start,
5672 buf->start + buf->len - 1, GFP_NOFS);
5674 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5675 buf->start + buf->len - 1, GFP_NOFS);
5677 trans->blocks_used++;
5678 /* this returns a buffer locked for blocking */
5682 static struct btrfs_block_rsv *
5683 use_block_rsv(struct btrfs_trans_handle *trans,
5684 struct btrfs_root *root, u32 blocksize)
5686 struct btrfs_block_rsv *block_rsv;
5687 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
5690 block_rsv = get_block_rsv(trans, root);
5692 if (block_rsv->size == 0) {
5693 ret = reserve_metadata_bytes(trans, root, block_rsv,
5696 * If we couldn't reserve metadata bytes try and use some from
5697 * the global reserve.
5699 if (ret && block_rsv != global_rsv) {
5700 ret = block_rsv_use_bytes(global_rsv, blocksize);
5703 return ERR_PTR(ret);
5705 return ERR_PTR(ret);
5710 ret = block_rsv_use_bytes(block_rsv, blocksize);
5715 ret = reserve_metadata_bytes(trans, root, block_rsv, blocksize,
5718 spin_lock(&block_rsv->lock);
5719 block_rsv->size += blocksize;
5720 spin_unlock(&block_rsv->lock);
5722 } else if (ret && block_rsv != global_rsv) {
5723 ret = block_rsv_use_bytes(global_rsv, blocksize);
5729 return ERR_PTR(-ENOSPC);
5732 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5734 block_rsv_add_bytes(block_rsv, blocksize, 0);
5735 block_rsv_release_bytes(block_rsv, NULL, 0);
5739 * finds a free extent and does all the dirty work required for allocation
5740 * returns the key for the extent through ins, and a tree buffer for
5741 * the first block of the extent through buf.
5743 * returns the tree buffer or NULL.
5745 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5746 struct btrfs_root *root, u32 blocksize,
5747 u64 parent, u64 root_objectid,
5748 struct btrfs_disk_key *key, int level,
5749 u64 hint, u64 empty_size)
5751 struct btrfs_key ins;
5752 struct btrfs_block_rsv *block_rsv;
5753 struct extent_buffer *buf;
5758 block_rsv = use_block_rsv(trans, root, blocksize);
5759 if (IS_ERR(block_rsv))
5760 return ERR_CAST(block_rsv);
5762 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5763 empty_size, hint, (u64)-1, &ins, 0);
5765 unuse_block_rsv(block_rsv, blocksize);
5766 return ERR_PTR(ret);
5769 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5771 BUG_ON(IS_ERR(buf));
5773 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5775 parent = ins.objectid;
5776 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5780 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5781 struct btrfs_delayed_extent_op *extent_op;
5782 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5785 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5787 memset(&extent_op->key, 0, sizeof(extent_op->key));
5788 extent_op->flags_to_set = flags;
5789 extent_op->update_key = 1;
5790 extent_op->update_flags = 1;
5791 extent_op->is_data = 0;
5793 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5794 ins.offset, parent, root_objectid,
5795 level, BTRFS_ADD_DELAYED_EXTENT,
5802 struct walk_control {
5803 u64 refs[BTRFS_MAX_LEVEL];
5804 u64 flags[BTRFS_MAX_LEVEL];
5805 struct btrfs_key update_progress;
5815 #define DROP_REFERENCE 1
5816 #define UPDATE_BACKREF 2
5818 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5819 struct btrfs_root *root,
5820 struct walk_control *wc,
5821 struct btrfs_path *path)
5829 struct btrfs_key key;
5830 struct extent_buffer *eb;
5835 if (path->slots[wc->level] < wc->reada_slot) {
5836 wc->reada_count = wc->reada_count * 2 / 3;
5837 wc->reada_count = max(wc->reada_count, 2);
5839 wc->reada_count = wc->reada_count * 3 / 2;
5840 wc->reada_count = min_t(int, wc->reada_count,
5841 BTRFS_NODEPTRS_PER_BLOCK(root));
5844 eb = path->nodes[wc->level];
5845 nritems = btrfs_header_nritems(eb);
5846 blocksize = btrfs_level_size(root, wc->level - 1);
5848 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5849 if (nread >= wc->reada_count)
5853 bytenr = btrfs_node_blockptr(eb, slot);
5854 generation = btrfs_node_ptr_generation(eb, slot);
5856 if (slot == path->slots[wc->level])
5859 if (wc->stage == UPDATE_BACKREF &&
5860 generation <= root->root_key.offset)
5863 /* We don't lock the tree block, it's OK to be racy here */
5864 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5869 if (wc->stage == DROP_REFERENCE) {
5873 if (wc->level == 1 &&
5874 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5876 if (!wc->update_ref ||
5877 generation <= root->root_key.offset)
5879 btrfs_node_key_to_cpu(eb, &key, slot);
5880 ret = btrfs_comp_cpu_keys(&key,
5881 &wc->update_progress);
5885 if (wc->level == 1 &&
5886 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5890 ret = readahead_tree_block(root, bytenr, blocksize,
5896 wc->reada_slot = slot;
5900 * hepler to process tree block while walking down the tree.
5902 * when wc->stage == UPDATE_BACKREF, this function updates
5903 * back refs for pointers in the block.
5905 * NOTE: return value 1 means we should stop walking down.
5907 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5908 struct btrfs_root *root,
5909 struct btrfs_path *path,
5910 struct walk_control *wc, int lookup_info)
5912 int level = wc->level;
5913 struct extent_buffer *eb = path->nodes[level];
5914 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5917 if (wc->stage == UPDATE_BACKREF &&
5918 btrfs_header_owner(eb) != root->root_key.objectid)
5922 * when reference count of tree block is 1, it won't increase
5923 * again. once full backref flag is set, we never clear it.
5926 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5927 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5928 BUG_ON(!path->locks[level]);
5929 ret = btrfs_lookup_extent_info(trans, root,
5934 BUG_ON(wc->refs[level] == 0);
5937 if (wc->stage == DROP_REFERENCE) {
5938 if (wc->refs[level] > 1)
5941 if (path->locks[level] && !wc->keep_locks) {
5942 btrfs_tree_unlock(eb);
5943 path->locks[level] = 0;
5948 /* wc->stage == UPDATE_BACKREF */
5949 if (!(wc->flags[level] & flag)) {
5950 BUG_ON(!path->locks[level]);
5951 ret = btrfs_inc_ref(trans, root, eb, 1);
5953 ret = btrfs_dec_ref(trans, root, eb, 0);
5955 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5958 wc->flags[level] |= flag;
5962 * the block is shared by multiple trees, so it's not good to
5963 * keep the tree lock
5965 if (path->locks[level] && level > 0) {
5966 btrfs_tree_unlock(eb);
5967 path->locks[level] = 0;
5973 * hepler to process tree block pointer.
5975 * when wc->stage == DROP_REFERENCE, this function checks
5976 * reference count of the block pointed to. if the block
5977 * is shared and we need update back refs for the subtree
5978 * rooted at the block, this function changes wc->stage to
5979 * UPDATE_BACKREF. if the block is shared and there is no
5980 * need to update back, this function drops the reference
5983 * NOTE: return value 1 means we should stop walking down.
5985 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5986 struct btrfs_root *root,
5987 struct btrfs_path *path,
5988 struct walk_control *wc, int *lookup_info)
5994 struct btrfs_key key;
5995 struct extent_buffer *next;
5996 int level = wc->level;
6000 generation = btrfs_node_ptr_generation(path->nodes[level],
6001 path->slots[level]);
6003 * if the lower level block was created before the snapshot
6004 * was created, we know there is no need to update back refs
6007 if (wc->stage == UPDATE_BACKREF &&
6008 generation <= root->root_key.offset) {
6013 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
6014 blocksize = btrfs_level_size(root, level - 1);
6016 next = btrfs_find_tree_block(root, bytenr, blocksize);
6018 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
6023 btrfs_tree_lock(next);
6024 btrfs_set_lock_blocking(next);
6026 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6027 &wc->refs[level - 1],
6028 &wc->flags[level - 1]);
6030 BUG_ON(wc->refs[level - 1] == 0);
6033 if (wc->stage == DROP_REFERENCE) {
6034 if (wc->refs[level - 1] > 1) {
6036 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6039 if (!wc->update_ref ||
6040 generation <= root->root_key.offset)
6043 btrfs_node_key_to_cpu(path->nodes[level], &key,
6044 path->slots[level]);
6045 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
6049 wc->stage = UPDATE_BACKREF;
6050 wc->shared_level = level - 1;
6054 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6058 if (!btrfs_buffer_uptodate(next, generation)) {
6059 btrfs_tree_unlock(next);
6060 free_extent_buffer(next);
6066 if (reada && level == 1)
6067 reada_walk_down(trans, root, wc, path);
6068 next = read_tree_block(root, bytenr, blocksize, generation);
6069 btrfs_tree_lock(next);
6070 btrfs_set_lock_blocking(next);
6074 BUG_ON(level != btrfs_header_level(next));
6075 path->nodes[level] = next;
6076 path->slots[level] = 0;
6077 path->locks[level] = 1;
6083 wc->refs[level - 1] = 0;
6084 wc->flags[level - 1] = 0;
6085 if (wc->stage == DROP_REFERENCE) {
6086 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6087 parent = path->nodes[level]->start;
6089 BUG_ON(root->root_key.objectid !=
6090 btrfs_header_owner(path->nodes[level]));
6094 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
6095 root->root_key.objectid, level - 1, 0);
6098 btrfs_tree_unlock(next);
6099 free_extent_buffer(next);
6105 * hepler to process tree block while walking up the tree.
6107 * when wc->stage == DROP_REFERENCE, this function drops
6108 * reference count on the block.
6110 * when wc->stage == UPDATE_BACKREF, this function changes
6111 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6112 * to UPDATE_BACKREF previously while processing the block.
6114 * NOTE: return value 1 means we should stop walking up.
6116 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6117 struct btrfs_root *root,
6118 struct btrfs_path *path,
6119 struct walk_control *wc)
6122 int level = wc->level;
6123 struct extent_buffer *eb = path->nodes[level];
6126 if (wc->stage == UPDATE_BACKREF) {
6127 BUG_ON(wc->shared_level < level);
6128 if (level < wc->shared_level)
6131 ret = find_next_key(path, level + 1, &wc->update_progress);
6135 wc->stage = DROP_REFERENCE;
6136 wc->shared_level = -1;
6137 path->slots[level] = 0;
6140 * check reference count again if the block isn't locked.
6141 * we should start walking down the tree again if reference
6144 if (!path->locks[level]) {
6146 btrfs_tree_lock(eb);
6147 btrfs_set_lock_blocking(eb);
6148 path->locks[level] = 1;
6150 ret = btrfs_lookup_extent_info(trans, root,
6155 BUG_ON(wc->refs[level] == 0);
6156 if (wc->refs[level] == 1) {
6157 btrfs_tree_unlock(eb);
6158 path->locks[level] = 0;
6164 /* wc->stage == DROP_REFERENCE */
6165 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6167 if (wc->refs[level] == 1) {
6169 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6170 ret = btrfs_dec_ref(trans, root, eb, 1);
6172 ret = btrfs_dec_ref(trans, root, eb, 0);
6175 /* make block locked assertion in clean_tree_block happy */
6176 if (!path->locks[level] &&
6177 btrfs_header_generation(eb) == trans->transid) {
6178 btrfs_tree_lock(eb);
6179 btrfs_set_lock_blocking(eb);
6180 path->locks[level] = 1;
6182 clean_tree_block(trans, root, eb);
6185 if (eb == root->node) {
6186 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6189 BUG_ON(root->root_key.objectid !=
6190 btrfs_header_owner(eb));
6192 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6193 parent = path->nodes[level + 1]->start;
6195 BUG_ON(root->root_key.objectid !=
6196 btrfs_header_owner(path->nodes[level + 1]));
6199 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6201 wc->refs[level] = 0;
6202 wc->flags[level] = 0;
6206 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6207 struct btrfs_root *root,
6208 struct btrfs_path *path,
6209 struct walk_control *wc)
6211 int level = wc->level;
6212 int lookup_info = 1;
6215 while (level >= 0) {
6216 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6223 if (path->slots[level] >=
6224 btrfs_header_nritems(path->nodes[level]))
6227 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6229 path->slots[level]++;
6238 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6239 struct btrfs_root *root,
6240 struct btrfs_path *path,
6241 struct walk_control *wc, int max_level)
6243 int level = wc->level;
6246 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6247 while (level < max_level && path->nodes[level]) {
6249 if (path->slots[level] + 1 <
6250 btrfs_header_nritems(path->nodes[level])) {
6251 path->slots[level]++;
6254 ret = walk_up_proc(trans, root, path, wc);
6258 if (path->locks[level]) {
6259 btrfs_tree_unlock(path->nodes[level]);
6260 path->locks[level] = 0;
6262 free_extent_buffer(path->nodes[level]);
6263 path->nodes[level] = NULL;
6271 * drop a subvolume tree.
6273 * this function traverses the tree freeing any blocks that only
6274 * referenced by the tree.
6276 * when a shared tree block is found. this function decreases its
6277 * reference count by one. if update_ref is true, this function
6278 * also make sure backrefs for the shared block and all lower level
6279 * blocks are properly updated.
6281 int btrfs_drop_snapshot(struct btrfs_root *root,
6282 struct btrfs_block_rsv *block_rsv, int update_ref)
6284 struct btrfs_path *path;
6285 struct btrfs_trans_handle *trans;
6286 struct btrfs_root *tree_root = root->fs_info->tree_root;
6287 struct btrfs_root_item *root_item = &root->root_item;
6288 struct walk_control *wc;
6289 struct btrfs_key key;
6294 path = btrfs_alloc_path();
6297 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6300 trans = btrfs_start_transaction(tree_root, 0);
6301 BUG_ON(IS_ERR(trans));
6304 trans->block_rsv = block_rsv;
6306 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6307 level = btrfs_header_level(root->node);
6308 path->nodes[level] = btrfs_lock_root_node(root);
6309 btrfs_set_lock_blocking(path->nodes[level]);
6310 path->slots[level] = 0;
6311 path->locks[level] = 1;
6312 memset(&wc->update_progress, 0,
6313 sizeof(wc->update_progress));
6315 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6316 memcpy(&wc->update_progress, &key,
6317 sizeof(wc->update_progress));
6319 level = root_item->drop_level;
6321 path->lowest_level = level;
6322 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6323 path->lowest_level = 0;
6331 * unlock our path, this is safe because only this
6332 * function is allowed to delete this snapshot
6334 btrfs_unlock_up_safe(path, 0);
6336 level = btrfs_header_level(root->node);
6338 btrfs_tree_lock(path->nodes[level]);
6339 btrfs_set_lock_blocking(path->nodes[level]);
6341 ret = btrfs_lookup_extent_info(trans, root,
6342 path->nodes[level]->start,
6343 path->nodes[level]->len,
6347 BUG_ON(wc->refs[level] == 0);
6349 if (level == root_item->drop_level)
6352 btrfs_tree_unlock(path->nodes[level]);
6353 WARN_ON(wc->refs[level] != 1);
6359 wc->shared_level = -1;
6360 wc->stage = DROP_REFERENCE;
6361 wc->update_ref = update_ref;
6363 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6366 ret = walk_down_tree(trans, root, path, wc);
6372 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6379 BUG_ON(wc->stage != DROP_REFERENCE);
6383 if (wc->stage == DROP_REFERENCE) {
6385 btrfs_node_key(path->nodes[level],
6386 &root_item->drop_progress,
6387 path->slots[level]);
6388 root_item->drop_level = level;
6391 BUG_ON(wc->level == 0);
6392 if (btrfs_should_end_transaction(trans, tree_root)) {
6393 ret = btrfs_update_root(trans, tree_root,
6398 btrfs_end_transaction_throttle(trans, tree_root);
6399 trans = btrfs_start_transaction(tree_root, 0);
6400 BUG_ON(IS_ERR(trans));
6402 trans->block_rsv = block_rsv;
6405 btrfs_release_path(root, path);
6408 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6411 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6412 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6416 /* if we fail to delete the orphan item this time
6417 * around, it'll get picked up the next time.
6419 * The most common failure here is just -ENOENT.
6421 btrfs_del_orphan_item(trans, tree_root,
6422 root->root_key.objectid);
6426 if (root->in_radix) {
6427 btrfs_free_fs_root(tree_root->fs_info, root);
6429 free_extent_buffer(root->node);
6430 free_extent_buffer(root->commit_root);
6434 btrfs_end_transaction_throttle(trans, tree_root);
6436 btrfs_free_path(path);
6441 * drop subtree rooted at tree block 'node'.
6443 * NOTE: this function will unlock and release tree block 'node'
6445 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6446 struct btrfs_root *root,
6447 struct extent_buffer *node,
6448 struct extent_buffer *parent)
6450 struct btrfs_path *path;
6451 struct walk_control *wc;
6457 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6459 path = btrfs_alloc_path();
6462 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6465 btrfs_assert_tree_locked(parent);
6466 parent_level = btrfs_header_level(parent);
6467 extent_buffer_get(parent);
6468 path->nodes[parent_level] = parent;
6469 path->slots[parent_level] = btrfs_header_nritems(parent);
6471 btrfs_assert_tree_locked(node);
6472 level = btrfs_header_level(node);
6473 path->nodes[level] = node;
6474 path->slots[level] = 0;
6475 path->locks[level] = 1;
6477 wc->refs[parent_level] = 1;
6478 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6480 wc->shared_level = -1;
6481 wc->stage = DROP_REFERENCE;
6484 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6487 wret = walk_down_tree(trans, root, path, wc);
6493 wret = walk_up_tree(trans, root, path, wc, parent_level);
6501 btrfs_free_path(path);
6506 static unsigned long calc_ra(unsigned long start, unsigned long last,
6509 return min(last, start + nr - 1);
6512 static noinline int relocate_inode_pages(struct inode *inode, u64 start,
6517 unsigned long first_index;
6518 unsigned long last_index;
6521 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6522 struct file_ra_state *ra;
6523 struct btrfs_ordered_extent *ordered;
6524 unsigned int total_read = 0;
6525 unsigned int total_dirty = 0;
6528 ra = kzalloc(sizeof(*ra), GFP_NOFS);
6532 mutex_lock(&inode->i_mutex);
6533 first_index = start >> PAGE_CACHE_SHIFT;
6534 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
6536 /* make sure the dirty trick played by the caller work */
6537 ret = invalidate_inode_pages2_range(inode->i_mapping,
6538 first_index, last_index);
6542 file_ra_state_init(ra, inode->i_mapping);
6544 for (i = first_index ; i <= last_index; i++) {
6545 if (total_read % ra->ra_pages == 0) {
6546 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
6547 calc_ra(i, last_index, ra->ra_pages));
6551 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
6553 page = grab_cache_page(inode->i_mapping, i);
6558 if (!PageUptodate(page)) {
6559 btrfs_readpage(NULL, page);
6561 if (!PageUptodate(page)) {
6563 page_cache_release(page);
6568 wait_on_page_writeback(page);
6570 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
6571 page_end = page_start + PAGE_CACHE_SIZE - 1;
6572 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
6574 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6576 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6578 page_cache_release(page);
6579 btrfs_start_ordered_extent(inode, ordered, 1);
6580 btrfs_put_ordered_extent(ordered);
6583 set_page_extent_mapped(page);
6585 if (i == first_index)
6586 set_extent_bits(io_tree, page_start, page_end,
6587 EXTENT_BOUNDARY, GFP_NOFS);
6588 btrfs_set_extent_delalloc(inode, page_start, page_end);
6590 set_page_dirty(page);
6593 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6595 page_cache_release(page);
6600 mutex_unlock(&inode->i_mutex);
6601 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
6605 static noinline int relocate_data_extent(struct inode *reloc_inode,
6606 struct btrfs_key *extent_key,
6609 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6610 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
6611 struct extent_map *em;
6612 u64 start = extent_key->objectid - offset;
6613 u64 end = start + extent_key->offset - 1;
6615 em = alloc_extent_map(GFP_NOFS);
6619 em->len = extent_key->offset;
6620 em->block_len = extent_key->offset;
6621 em->block_start = extent_key->objectid;
6622 em->bdev = root->fs_info->fs_devices->latest_bdev;
6623 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6625 /* setup extent map to cheat btrfs_readpage */
6626 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6629 write_lock(&em_tree->lock);
6630 ret = add_extent_mapping(em_tree, em);
6631 write_unlock(&em_tree->lock);
6632 if (ret != -EEXIST) {
6633 free_extent_map(em);
6636 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
6638 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6640 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
6643 struct btrfs_ref_path {
6645 u64 nodes[BTRFS_MAX_LEVEL];
6647 u64 root_generation;
6654 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
6655 u64 new_nodes[BTRFS_MAX_LEVEL];
6658 struct disk_extent {
6669 static int is_cowonly_root(u64 root_objectid)
6671 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
6672 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
6673 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
6674 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
6675 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
6676 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
6681 static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
6682 struct btrfs_root *extent_root,
6683 struct btrfs_ref_path *ref_path,
6686 struct extent_buffer *leaf;
6687 struct btrfs_path *path;
6688 struct btrfs_extent_ref *ref;
6689 struct btrfs_key key;
6690 struct btrfs_key found_key;
6696 path = btrfs_alloc_path();
6701 ref_path->lowest_level = -1;
6702 ref_path->current_level = -1;
6703 ref_path->shared_level = -1;
6707 level = ref_path->current_level - 1;
6708 while (level >= -1) {
6710 if (level < ref_path->lowest_level)
6714 bytenr = ref_path->nodes[level];
6716 bytenr = ref_path->extent_start;
6717 BUG_ON(bytenr == 0);
6719 parent = ref_path->nodes[level + 1];
6720 ref_path->nodes[level + 1] = 0;
6721 ref_path->current_level = level;
6722 BUG_ON(parent == 0);
6724 key.objectid = bytenr;
6725 key.offset = parent + 1;
6726 key.type = BTRFS_EXTENT_REF_KEY;
6728 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6733 leaf = path->nodes[0];
6734 nritems = btrfs_header_nritems(leaf);
6735 if (path->slots[0] >= nritems) {
6736 ret = btrfs_next_leaf(extent_root, path);
6741 leaf = path->nodes[0];
6744 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6745 if (found_key.objectid == bytenr &&
6746 found_key.type == BTRFS_EXTENT_REF_KEY) {
6747 if (level < ref_path->shared_level)
6748 ref_path->shared_level = level;
6753 btrfs_release_path(extent_root, path);
6756 /* reached lowest level */
6760 level = ref_path->current_level;
6761 while (level < BTRFS_MAX_LEVEL - 1) {
6765 bytenr = ref_path->nodes[level];
6767 bytenr = ref_path->extent_start;
6769 BUG_ON(bytenr == 0);
6771 key.objectid = bytenr;
6773 key.type = BTRFS_EXTENT_REF_KEY;
6775 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6779 leaf = path->nodes[0];
6780 nritems = btrfs_header_nritems(leaf);
6781 if (path->slots[0] >= nritems) {
6782 ret = btrfs_next_leaf(extent_root, path);
6786 /* the extent was freed by someone */
6787 if (ref_path->lowest_level == level)
6789 btrfs_release_path(extent_root, path);
6792 leaf = path->nodes[0];
6795 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6796 if (found_key.objectid != bytenr ||
6797 found_key.type != BTRFS_EXTENT_REF_KEY) {
6798 /* the extent was freed by someone */
6799 if (ref_path->lowest_level == level) {
6803 btrfs_release_path(extent_root, path);
6807 ref = btrfs_item_ptr(leaf, path->slots[0],
6808 struct btrfs_extent_ref);
6809 ref_objectid = btrfs_ref_objectid(leaf, ref);
6810 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
6812 level = (int)ref_objectid;
6813 BUG_ON(level >= BTRFS_MAX_LEVEL);
6814 ref_path->lowest_level = level;
6815 ref_path->current_level = level;
6816 ref_path->nodes[level] = bytenr;
6818 WARN_ON(ref_objectid != level);
6821 WARN_ON(level != -1);
6825 if (ref_path->lowest_level == level) {
6826 ref_path->owner_objectid = ref_objectid;
6827 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
6831 * the block is tree root or the block isn't in reference
6834 if (found_key.objectid == found_key.offset ||
6835 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
6836 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6837 ref_path->root_generation =
6838 btrfs_ref_generation(leaf, ref);
6840 /* special reference from the tree log */
6841 ref_path->nodes[0] = found_key.offset;
6842 ref_path->current_level = 0;
6849 BUG_ON(ref_path->nodes[level] != 0);
6850 ref_path->nodes[level] = found_key.offset;
6851 ref_path->current_level = level;
6854 * the reference was created in the running transaction,
6855 * no need to continue walking up.
6857 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
6858 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6859 ref_path->root_generation =
6860 btrfs_ref_generation(leaf, ref);
6865 btrfs_release_path(extent_root, path);
6868 /* reached max tree level, but no tree root found. */
6871 btrfs_free_path(path);
6875 static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
6876 struct btrfs_root *extent_root,
6877 struct btrfs_ref_path *ref_path,
6880 memset(ref_path, 0, sizeof(*ref_path));
6881 ref_path->extent_start = extent_start;
6883 return __next_ref_path(trans, extent_root, ref_path, 1);
6886 static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
6887 struct btrfs_root *extent_root,
6888 struct btrfs_ref_path *ref_path)
6890 return __next_ref_path(trans, extent_root, ref_path, 0);
6893 static noinline int get_new_locations(struct inode *reloc_inode,
6894 struct btrfs_key *extent_key,
6895 u64 offset, int no_fragment,
6896 struct disk_extent **extents,
6899 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6900 struct btrfs_path *path;
6901 struct btrfs_file_extent_item *fi;
6902 struct extent_buffer *leaf;
6903 struct disk_extent *exts = *extents;
6904 struct btrfs_key found_key;
6909 int max = *nr_extents;
6912 WARN_ON(!no_fragment && *extents);
6915 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
6920 path = btrfs_alloc_path();
6923 cur_pos = extent_key->objectid - offset;
6924 last_byte = extent_key->objectid + extent_key->offset;
6925 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
6935 leaf = path->nodes[0];
6936 nritems = btrfs_header_nritems(leaf);
6937 if (path->slots[0] >= nritems) {
6938 ret = btrfs_next_leaf(root, path);
6943 leaf = path->nodes[0];
6946 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6947 if (found_key.offset != cur_pos ||
6948 found_key.type != BTRFS_EXTENT_DATA_KEY ||
6949 found_key.objectid != reloc_inode->i_ino)
6952 fi = btrfs_item_ptr(leaf, path->slots[0],
6953 struct btrfs_file_extent_item);
6954 if (btrfs_file_extent_type(leaf, fi) !=
6955 BTRFS_FILE_EXTENT_REG ||
6956 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6960 struct disk_extent *old = exts;
6962 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
6963 memcpy(exts, old, sizeof(*exts) * nr);
6964 if (old != *extents)
6968 exts[nr].disk_bytenr =
6969 btrfs_file_extent_disk_bytenr(leaf, fi);
6970 exts[nr].disk_num_bytes =
6971 btrfs_file_extent_disk_num_bytes(leaf, fi);
6972 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
6973 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6974 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6975 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
6976 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
6977 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
6979 BUG_ON(exts[nr].offset > 0);
6980 BUG_ON(exts[nr].compression || exts[nr].encryption);
6981 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
6983 cur_pos += exts[nr].num_bytes;
6986 if (cur_pos + offset >= last_byte)
6996 BUG_ON(cur_pos + offset > last_byte);
6997 if (cur_pos + offset < last_byte) {
7003 btrfs_free_path(path);
7005 if (exts != *extents)
7014 static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
7015 struct btrfs_root *root,
7016 struct btrfs_path *path,
7017 struct btrfs_key *extent_key,
7018 struct btrfs_key *leaf_key,
7019 struct btrfs_ref_path *ref_path,
7020 struct disk_extent *new_extents,
7023 struct extent_buffer *leaf;
7024 struct btrfs_file_extent_item *fi;
7025 struct inode *inode = NULL;
7026 struct btrfs_key key;
7031 u64 search_end = (u64)-1;
7034 int extent_locked = 0;
7038 memcpy(&key, leaf_key, sizeof(key));
7039 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
7040 if (key.objectid < ref_path->owner_objectid ||
7041 (key.objectid == ref_path->owner_objectid &&
7042 key.type < BTRFS_EXTENT_DATA_KEY)) {
7043 key.objectid = ref_path->owner_objectid;
7044 key.type = BTRFS_EXTENT_DATA_KEY;
7050 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
7054 leaf = path->nodes[0];
7055 nritems = btrfs_header_nritems(leaf);
7057 if (extent_locked && ret > 0) {
7059 * the file extent item was modified by someone
7060 * before the extent got locked.
7062 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7063 lock_end, GFP_NOFS);
7067 if (path->slots[0] >= nritems) {
7068 if (++nr_scaned > 2)
7071 BUG_ON(extent_locked);
7072 ret = btrfs_next_leaf(root, path);
7077 leaf = path->nodes[0];
7078 nritems = btrfs_header_nritems(leaf);
7081 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
7083 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
7084 if ((key.objectid > ref_path->owner_objectid) ||
7085 (key.objectid == ref_path->owner_objectid &&
7086 key.type > BTRFS_EXTENT_DATA_KEY) ||
7087 key.offset >= search_end)
7091 if (inode && key.objectid != inode->i_ino) {
7092 BUG_ON(extent_locked);
7093 btrfs_release_path(root, path);
7094 mutex_unlock(&inode->i_mutex);
7100 if (key.type != BTRFS_EXTENT_DATA_KEY) {
7105 fi = btrfs_item_ptr(leaf, path->slots[0],
7106 struct btrfs_file_extent_item);
7107 extent_type = btrfs_file_extent_type(leaf, fi);
7108 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
7109 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
7110 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
7111 extent_key->objectid)) {
7117 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7118 ext_offset = btrfs_file_extent_offset(leaf, fi);
7120 if (search_end == (u64)-1) {
7121 search_end = key.offset - ext_offset +
7122 btrfs_file_extent_ram_bytes(leaf, fi);
7125 if (!extent_locked) {
7126 lock_start = key.offset;
7127 lock_end = lock_start + num_bytes - 1;
7129 if (lock_start > key.offset ||
7130 lock_end + 1 < key.offset + num_bytes) {
7131 unlock_extent(&BTRFS_I(inode)->io_tree,
7132 lock_start, lock_end, GFP_NOFS);
7138 btrfs_release_path(root, path);
7140 inode = btrfs_iget_locked(root->fs_info->sb,
7141 key.objectid, root);
7142 if (inode->i_state & I_NEW) {
7143 BTRFS_I(inode)->root = root;
7144 BTRFS_I(inode)->location.objectid =
7146 BTRFS_I(inode)->location.type =
7147 BTRFS_INODE_ITEM_KEY;
7148 BTRFS_I(inode)->location.offset = 0;
7149 btrfs_read_locked_inode(inode);
7150 unlock_new_inode(inode);
7153 * some code call btrfs_commit_transaction while
7154 * holding the i_mutex, so we can't use mutex_lock
7157 if (is_bad_inode(inode) ||
7158 !mutex_trylock(&inode->i_mutex)) {
7161 key.offset = (u64)-1;
7166 if (!extent_locked) {
7167 struct btrfs_ordered_extent *ordered;
7169 btrfs_release_path(root, path);
7171 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7172 lock_end, GFP_NOFS);
7173 ordered = btrfs_lookup_first_ordered_extent(inode,
7176 ordered->file_offset <= lock_end &&
7177 ordered->file_offset + ordered->len > lock_start) {
7178 unlock_extent(&BTRFS_I(inode)->io_tree,
7179 lock_start, lock_end, GFP_NOFS);
7180 btrfs_start_ordered_extent(inode, ordered, 1);
7181 btrfs_put_ordered_extent(ordered);
7182 key.offset += num_bytes;
7186 btrfs_put_ordered_extent(ordered);
7192 if (nr_extents == 1) {
7193 /* update extent pointer in place */
7194 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7195 new_extents[0].disk_bytenr);
7196 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7197 new_extents[0].disk_num_bytes);
7198 btrfs_mark_buffer_dirty(leaf);
7200 btrfs_drop_extent_cache(inode, key.offset,
7201 key.offset + num_bytes - 1, 0);
7203 ret = btrfs_inc_extent_ref(trans, root,
7204 new_extents[0].disk_bytenr,
7205 new_extents[0].disk_num_bytes,
7207 root->root_key.objectid,
7212 ret = btrfs_free_extent(trans, root,
7213 extent_key->objectid,
7216 btrfs_header_owner(leaf),
7217 btrfs_header_generation(leaf),
7221 btrfs_release_path(root, path);
7222 key.offset += num_bytes;
7230 * drop old extent pointer at first, then insert the
7231 * new pointers one bye one
7233 btrfs_release_path(root, path);
7234 ret = btrfs_drop_extents(trans, root, inode, key.offset,
7235 key.offset + num_bytes,
7236 key.offset, &alloc_hint);
7239 for (i = 0; i < nr_extents; i++) {
7240 if (ext_offset >= new_extents[i].num_bytes) {
7241 ext_offset -= new_extents[i].num_bytes;
7244 extent_len = min(new_extents[i].num_bytes -
7245 ext_offset, num_bytes);
7247 ret = btrfs_insert_empty_item(trans, root,
7252 leaf = path->nodes[0];
7253 fi = btrfs_item_ptr(leaf, path->slots[0],
7254 struct btrfs_file_extent_item);
7255 btrfs_set_file_extent_generation(leaf, fi,
7257 btrfs_set_file_extent_type(leaf, fi,
7258 BTRFS_FILE_EXTENT_REG);
7259 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7260 new_extents[i].disk_bytenr);
7261 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7262 new_extents[i].disk_num_bytes);
7263 btrfs_set_file_extent_ram_bytes(leaf, fi,
7264 new_extents[i].ram_bytes);
7266 btrfs_set_file_extent_compression(leaf, fi,
7267 new_extents[i].compression);
7268 btrfs_set_file_extent_encryption(leaf, fi,
7269 new_extents[i].encryption);
7270 btrfs_set_file_extent_other_encoding(leaf, fi,
7271 new_extents[i].other_encoding);
7273 btrfs_set_file_extent_num_bytes(leaf, fi,
7275 ext_offset += new_extents[i].offset;
7276 btrfs_set_file_extent_offset(leaf, fi,
7278 btrfs_mark_buffer_dirty(leaf);
7280 btrfs_drop_extent_cache(inode, key.offset,
7281 key.offset + extent_len - 1, 0);
7283 ret = btrfs_inc_extent_ref(trans, root,
7284 new_extents[i].disk_bytenr,
7285 new_extents[i].disk_num_bytes,
7287 root->root_key.objectid,
7288 trans->transid, key.objectid);
7290 btrfs_release_path(root, path);
7292 inode_add_bytes(inode, extent_len);
7295 num_bytes -= extent_len;
7296 key.offset += extent_len;
7301 BUG_ON(i >= nr_extents);
7305 if (extent_locked) {
7306 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7307 lock_end, GFP_NOFS);
7311 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
7312 key.offset >= search_end)
7319 btrfs_release_path(root, path);
7321 mutex_unlock(&inode->i_mutex);
7322 if (extent_locked) {
7323 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7324 lock_end, GFP_NOFS);
7331 int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
7332 struct btrfs_root *root,
7333 struct extent_buffer *buf, u64 orig_start)
7338 BUG_ON(btrfs_header_generation(buf) != trans->transid);
7339 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
7341 level = btrfs_header_level(buf);
7343 struct btrfs_leaf_ref *ref;
7344 struct btrfs_leaf_ref *orig_ref;
7346 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
7350 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
7352 btrfs_free_leaf_ref(root, orig_ref);
7356 ref->nritems = orig_ref->nritems;
7357 memcpy(ref->extents, orig_ref->extents,
7358 sizeof(ref->extents[0]) * ref->nritems);
7360 btrfs_free_leaf_ref(root, orig_ref);
7362 ref->root_gen = trans->transid;
7363 ref->bytenr = buf->start;
7364 ref->owner = btrfs_header_owner(buf);
7365 ref->generation = btrfs_header_generation(buf);
7367 ret = btrfs_add_leaf_ref(root, ref, 0);
7369 btrfs_free_leaf_ref(root, ref);
7374 static noinline int invalidate_extent_cache(struct btrfs_root *root,
7375 struct extent_buffer *leaf,
7376 struct btrfs_block_group_cache *group,
7377 struct btrfs_root *target_root)
7379 struct btrfs_key key;
7380 struct inode *inode = NULL;
7381 struct btrfs_file_extent_item *fi;
7382 struct extent_state *cached_state = NULL;
7384 u64 skip_objectid = 0;
7388 nritems = btrfs_header_nritems(leaf);
7389 for (i = 0; i < nritems; i++) {
7390 btrfs_item_key_to_cpu(leaf, &key, i);
7391 if (key.objectid == skip_objectid ||
7392 key.type != BTRFS_EXTENT_DATA_KEY)
7394 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7395 if (btrfs_file_extent_type(leaf, fi) ==
7396 BTRFS_FILE_EXTENT_INLINE)
7398 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
7400 if (!inode || inode->i_ino != key.objectid) {
7402 inode = btrfs_ilookup(target_root->fs_info->sb,
7403 key.objectid, target_root, 1);
7406 skip_objectid = key.objectid;
7409 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7411 lock_extent_bits(&BTRFS_I(inode)->io_tree, key.offset,
7412 key.offset + num_bytes - 1, 0, &cached_state,
7414 btrfs_drop_extent_cache(inode, key.offset,
7415 key.offset + num_bytes - 1, 1);
7416 unlock_extent_cached(&BTRFS_I(inode)->io_tree, key.offset,
7417 key.offset + num_bytes - 1, &cached_state,
7425 static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
7426 struct btrfs_root *root,
7427 struct extent_buffer *leaf,
7428 struct btrfs_block_group_cache *group,
7429 struct inode *reloc_inode)
7431 struct btrfs_key key;
7432 struct btrfs_key extent_key;
7433 struct btrfs_file_extent_item *fi;
7434 struct btrfs_leaf_ref *ref;
7435 struct disk_extent *new_extent;
7444 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
7445 BUG_ON(!new_extent);
7447 ref = btrfs_lookup_leaf_ref(root, leaf->start);
7451 nritems = btrfs_header_nritems(leaf);
7452 for (i = 0; i < nritems; i++) {
7453 btrfs_item_key_to_cpu(leaf, &key, i);
7454 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
7456 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7457 if (btrfs_file_extent_type(leaf, fi) ==
7458 BTRFS_FILE_EXTENT_INLINE)
7460 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
7461 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
7466 if (bytenr >= group->key.objectid + group->key.offset ||
7467 bytenr + num_bytes <= group->key.objectid)
7470 extent_key.objectid = bytenr;
7471 extent_key.offset = num_bytes;
7472 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
7474 ret = get_new_locations(reloc_inode, &extent_key,
7475 group->key.objectid, 1,
7476 &new_extent, &nr_extent);
7481 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
7482 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
7483 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
7484 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
7486 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7487 new_extent->disk_bytenr);
7488 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7489 new_extent->disk_num_bytes);
7490 btrfs_mark_buffer_dirty(leaf);
7492 ret = btrfs_inc_extent_ref(trans, root,
7493 new_extent->disk_bytenr,
7494 new_extent->disk_num_bytes,
7496 root->root_key.objectid,
7497 trans->transid, key.objectid);
7500 ret = btrfs_free_extent(trans, root,
7501 bytenr, num_bytes, leaf->start,
7502 btrfs_header_owner(leaf),
7503 btrfs_header_generation(leaf),
7509 BUG_ON(ext_index + 1 != ref->nritems);
7510 btrfs_free_leaf_ref(root, ref);
7514 int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
7515 struct btrfs_root *root)
7517 struct btrfs_root *reloc_root;
7520 if (root->reloc_root) {
7521 reloc_root = root->reloc_root;
7522 root->reloc_root = NULL;
7523 list_add(&reloc_root->dead_list,
7524 &root->fs_info->dead_reloc_roots);
7526 btrfs_set_root_bytenr(&reloc_root->root_item,
7527 reloc_root->node->start);
7528 btrfs_set_root_level(&root->root_item,
7529 btrfs_header_level(reloc_root->node));
7530 memset(&reloc_root->root_item.drop_progress, 0,
7531 sizeof(struct btrfs_disk_key));
7532 reloc_root->root_item.drop_level = 0;
7534 ret = btrfs_update_root(trans, root->fs_info->tree_root,
7535 &reloc_root->root_key,
7536 &reloc_root->root_item);
7542 int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
7544 struct btrfs_trans_handle *trans;
7545 struct btrfs_root *reloc_root;
7546 struct btrfs_root *prev_root = NULL;
7547 struct list_head dead_roots;
7551 INIT_LIST_HEAD(&dead_roots);
7552 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
7554 while (!list_empty(&dead_roots)) {
7555 reloc_root = list_entry(dead_roots.prev,
7556 struct btrfs_root, dead_list);
7557 list_del_init(&reloc_root->dead_list);
7559 BUG_ON(reloc_root->commit_root != NULL);
7561 trans = btrfs_join_transaction(root, 1);
7562 BUG_ON(IS_ERR(trans));
7564 mutex_lock(&root->fs_info->drop_mutex);
7565 ret = btrfs_drop_snapshot(trans, reloc_root);
7568 mutex_unlock(&root->fs_info->drop_mutex);
7570 nr = trans->blocks_used;
7571 ret = btrfs_end_transaction(trans, root);
7573 btrfs_btree_balance_dirty(root, nr);
7576 free_extent_buffer(reloc_root->node);
7578 ret = btrfs_del_root(trans, root->fs_info->tree_root,
7579 &reloc_root->root_key);
7581 mutex_unlock(&root->fs_info->drop_mutex);
7583 nr = trans->blocks_used;
7584 ret = btrfs_end_transaction(trans, root);
7586 btrfs_btree_balance_dirty(root, nr);
7589 prev_root = reloc_root;
7592 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
7598 int btrfs_add_dead_reloc_root(struct btrfs_root *root)
7600 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
7604 int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
7606 struct btrfs_root *reloc_root;
7607 struct btrfs_trans_handle *trans;
7608 struct btrfs_key location;
7612 mutex_lock(&root->fs_info->tree_reloc_mutex);
7613 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
7615 found = !list_empty(&root->fs_info->dead_reloc_roots);
7616 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7619 trans = btrfs_start_transaction(root, 1);
7620 BUG_ON(IS_ERR(trans));
7621 ret = btrfs_commit_transaction(trans, root);
7625 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
7626 location.offset = (u64)-1;
7627 location.type = BTRFS_ROOT_ITEM_KEY;
7629 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
7630 BUG_ON(!reloc_root);
7631 ret = btrfs_orphan_cleanup(reloc_root);
7636 static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
7637 struct btrfs_root *root)
7639 struct btrfs_root *reloc_root;
7640 struct extent_buffer *eb;
7641 struct btrfs_root_item *root_item;
7642 struct btrfs_key root_key;
7645 BUG_ON(!root->ref_cows);
7646 if (root->reloc_root)
7649 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
7652 ret = btrfs_copy_root(trans, root, root->commit_root,
7653 &eb, BTRFS_TREE_RELOC_OBJECTID);
7656 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
7657 root_key.offset = root->root_key.objectid;
7658 root_key.type = BTRFS_ROOT_ITEM_KEY;
7660 memcpy(root_item, &root->root_item, sizeof(root_item));
7661 btrfs_set_root_refs(root_item, 0);
7662 btrfs_set_root_bytenr(root_item, eb->start);
7663 btrfs_set_root_level(root_item, btrfs_header_level(eb));
7664 btrfs_set_root_generation(root_item, trans->transid);
7666 btrfs_tree_unlock(eb);
7667 free_extent_buffer(eb);
7669 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
7670 &root_key, root_item);
7674 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
7676 BUG_ON(!reloc_root);
7677 reloc_root->last_trans = trans->transid;
7678 reloc_root->commit_root = NULL;
7679 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
7681 root->reloc_root = reloc_root;
7686 * Core function of space balance.
7688 * The idea is using reloc trees to relocate tree blocks in reference
7689 * counted roots. There is one reloc tree for each subvol, and all
7690 * reloc trees share same root key objectid. Reloc trees are snapshots
7691 * of the latest committed roots of subvols (root->commit_root).
7693 * To relocate a tree block referenced by a subvol, there are two steps.
7694 * COW the block through subvol's reloc tree, then update block pointer
7695 * in the subvol to point to the new block. Since all reloc trees share
7696 * same root key objectid, doing special handing for tree blocks owned
7697 * by them is easy. Once a tree block has been COWed in one reloc tree,
7698 * we can use the resulting new block directly when the same block is
7699 * required to COW again through other reloc trees. By this way, relocated
7700 * tree blocks are shared between reloc trees, so they are also shared
7703 static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
7704 struct btrfs_root *root,
7705 struct btrfs_path *path,
7706 struct btrfs_key *first_key,
7707 struct btrfs_ref_path *ref_path,
7708 struct btrfs_block_group_cache *group,
7709 struct inode *reloc_inode)
7711 struct btrfs_root *reloc_root;
7712 struct extent_buffer *eb = NULL;
7713 struct btrfs_key *keys;
7717 int lowest_level = 0;
7720 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
7721 lowest_level = ref_path->owner_objectid;
7723 if (!root->ref_cows) {
7724 path->lowest_level = lowest_level;
7725 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
7727 path->lowest_level = 0;
7728 btrfs_release_path(root, path);
7732 mutex_lock(&root->fs_info->tree_reloc_mutex);
7733 ret = init_reloc_tree(trans, root);
7735 reloc_root = root->reloc_root;
7737 shared_level = ref_path->shared_level;
7738 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
7740 keys = ref_path->node_keys;
7741 nodes = ref_path->new_nodes;
7742 memset(&keys[shared_level + 1], 0,
7743 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
7744 memset(&nodes[shared_level + 1], 0,
7745 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
7747 if (nodes[lowest_level] == 0) {
7748 path->lowest_level = lowest_level;
7749 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7752 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
7753 eb = path->nodes[level];
7754 if (!eb || eb == reloc_root->node)
7756 nodes[level] = eb->start;
7758 btrfs_item_key_to_cpu(eb, &keys[level], 0);
7760 btrfs_node_key_to_cpu(eb, &keys[level], 0);
7763 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7764 eb = path->nodes[0];
7765 ret = replace_extents_in_leaf(trans, reloc_root, eb,
7766 group, reloc_inode);
7769 btrfs_release_path(reloc_root, path);
7771 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
7777 * replace tree blocks in the fs tree with tree blocks in
7780 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
7783 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7784 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7787 extent_buffer_get(path->nodes[0]);
7788 eb = path->nodes[0];
7789 btrfs_release_path(reloc_root, path);
7790 ret = invalidate_extent_cache(reloc_root, eb, group, root);
7792 free_extent_buffer(eb);
7795 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7796 path->lowest_level = 0;
7800 static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
7801 struct btrfs_root *root,
7802 struct btrfs_path *path,
7803 struct btrfs_key *first_key,
7804 struct btrfs_ref_path *ref_path)
7808 ret = relocate_one_path(trans, root, path, first_key,
7809 ref_path, NULL, NULL);
7815 static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
7816 struct btrfs_root *extent_root,
7817 struct btrfs_path *path,
7818 struct btrfs_key *extent_key)
7822 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
7825 ret = btrfs_del_item(trans, extent_root, path);
7827 btrfs_release_path(extent_root, path);
7831 static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
7832 struct btrfs_ref_path *ref_path)
7834 struct btrfs_key root_key;
7836 root_key.objectid = ref_path->root_objectid;
7837 root_key.type = BTRFS_ROOT_ITEM_KEY;
7838 if (is_cowonly_root(ref_path->root_objectid))
7839 root_key.offset = 0;
7841 root_key.offset = (u64)-1;
7843 return btrfs_read_fs_root_no_name(fs_info, &root_key);
7846 static noinline int relocate_one_extent(struct btrfs_root *extent_root,
7847 struct btrfs_path *path,
7848 struct btrfs_key *extent_key,
7849 struct btrfs_block_group_cache *group,
7850 struct inode *reloc_inode, int pass)
7852 struct btrfs_trans_handle *trans;
7853 struct btrfs_root *found_root;
7854 struct btrfs_ref_path *ref_path = NULL;
7855 struct disk_extent *new_extents = NULL;
7860 struct btrfs_key first_key;
7864 trans = btrfs_start_transaction(extent_root, 1);
7865 BUG_ON(IS_ERR(trans));
7867 if (extent_key->objectid == 0) {
7868 ret = del_extent_zero(trans, extent_root, path, extent_key);
7872 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
7878 for (loops = 0; ; loops++) {
7880 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
7881 extent_key->objectid);
7883 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
7890 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
7891 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
7894 found_root = read_ref_root(extent_root->fs_info, ref_path);
7895 BUG_ON(!found_root);
7897 * for reference counted tree, only process reference paths
7898 * rooted at the latest committed root.
7900 if (found_root->ref_cows &&
7901 ref_path->root_generation != found_root->root_key.offset)
7904 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7907 * copy data extents to new locations
7909 u64 group_start = group->key.objectid;
7910 ret = relocate_data_extent(reloc_inode,
7919 level = ref_path->owner_objectid;
7922 if (prev_block != ref_path->nodes[level]) {
7923 struct extent_buffer *eb;
7924 u64 block_start = ref_path->nodes[level];
7925 u64 block_size = btrfs_level_size(found_root, level);
7927 eb = read_tree_block(found_root, block_start,
7929 btrfs_tree_lock(eb);
7930 BUG_ON(level != btrfs_header_level(eb));
7933 btrfs_item_key_to_cpu(eb, &first_key, 0);
7935 btrfs_node_key_to_cpu(eb, &first_key, 0);
7937 btrfs_tree_unlock(eb);
7938 free_extent_buffer(eb);
7939 prev_block = block_start;
7942 mutex_lock(&extent_root->fs_info->trans_mutex);
7943 btrfs_record_root_in_trans(found_root);
7944 mutex_unlock(&extent_root->fs_info->trans_mutex);
7945 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7947 * try to update data extent references while
7948 * keeping metadata shared between snapshots.
7951 ret = relocate_one_path(trans, found_root,
7952 path, &first_key, ref_path,
7953 group, reloc_inode);
7959 * use fallback method to process the remaining
7963 u64 group_start = group->key.objectid;
7964 new_extents = kmalloc(sizeof(*new_extents),
7967 ret = get_new_locations(reloc_inode,
7975 ret = replace_one_extent(trans, found_root,
7977 &first_key, ref_path,
7978 new_extents, nr_extents);
7980 ret = relocate_tree_block(trans, found_root, path,
7981 &first_key, ref_path);
7988 btrfs_end_transaction(trans, extent_root);
7995 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
7998 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
7999 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
8002 * we add in the count of missing devices because we want
8003 * to make sure that any RAID levels on a degraded FS
8004 * continue to be honored.
8006 num_devices = root->fs_info->fs_devices->rw_devices +
8007 root->fs_info->fs_devices->missing_devices;
8009 if (num_devices == 1) {
8010 stripped |= BTRFS_BLOCK_GROUP_DUP;
8011 stripped = flags & ~stripped;
8013 /* turn raid0 into single device chunks */
8014 if (flags & BTRFS_BLOCK_GROUP_RAID0)
8017 /* turn mirroring into duplication */
8018 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
8019 BTRFS_BLOCK_GROUP_RAID10))
8020 return stripped | BTRFS_BLOCK_GROUP_DUP;
8023 /* they already had raid on here, just return */
8024 if (flags & stripped)
8027 stripped |= BTRFS_BLOCK_GROUP_DUP;
8028 stripped = flags & ~stripped;
8030 /* switch duplicated blocks with raid1 */
8031 if (flags & BTRFS_BLOCK_GROUP_DUP)
8032 return stripped | BTRFS_BLOCK_GROUP_RAID1;
8034 /* turn single device chunks into raid0 */
8035 return stripped | BTRFS_BLOCK_GROUP_RAID0;
8040 static int set_block_group_ro(struct btrfs_block_group_cache *cache)
8042 struct btrfs_space_info *sinfo = cache->space_info;
8049 spin_lock(&sinfo->lock);
8050 spin_lock(&cache->lock);
8051 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
8052 cache->bytes_super - btrfs_block_group_used(&cache->item);
8054 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
8055 sinfo->bytes_may_use + sinfo->bytes_readonly +
8056 cache->reserved_pinned + num_bytes <= sinfo->total_bytes) {
8057 sinfo->bytes_readonly += num_bytes;
8058 sinfo->bytes_reserved += cache->reserved_pinned;
8059 cache->reserved_pinned = 0;
8064 spin_unlock(&cache->lock);
8065 spin_unlock(&sinfo->lock);
8069 int btrfs_set_block_group_ro(struct btrfs_root *root,
8070 struct btrfs_block_group_cache *cache)
8073 struct btrfs_trans_handle *trans;
8079 trans = btrfs_join_transaction(root, 1);
8080 BUG_ON(IS_ERR(trans));
8082 alloc_flags = update_block_group_flags(root, cache->flags);
8083 if (alloc_flags != cache->flags)
8084 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
8086 ret = set_block_group_ro(cache);
8089 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
8090 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
8093 ret = set_block_group_ro(cache);
8095 btrfs_end_transaction(trans, root);
8099 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
8100 struct btrfs_root *root, u64 type)
8102 u64 alloc_flags = get_alloc_profile(root, type);
8103 return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
8107 * helper to account the unused space of all the readonly block group in the
8108 * list. takes mirrors into account.
8110 static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
8112 struct btrfs_block_group_cache *block_group;
8116 list_for_each_entry(block_group, groups_list, list) {
8117 spin_lock(&block_group->lock);
8119 if (!block_group->ro) {
8120 spin_unlock(&block_group->lock);
8124 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
8125 BTRFS_BLOCK_GROUP_RAID10 |
8126 BTRFS_BLOCK_GROUP_DUP))
8131 free_bytes += (block_group->key.offset -
8132 btrfs_block_group_used(&block_group->item)) *
8135 spin_unlock(&block_group->lock);
8142 * helper to account the unused space of all the readonly block group in the
8143 * space_info. takes mirrors into account.
8145 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
8150 spin_lock(&sinfo->lock);
8152 for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
8153 if (!list_empty(&sinfo->block_groups[i]))
8154 free_bytes += __btrfs_get_ro_block_group_free_space(
8155 &sinfo->block_groups[i]);
8157 spin_unlock(&sinfo->lock);
8162 int btrfs_set_block_group_rw(struct btrfs_root *root,
8163 struct btrfs_block_group_cache *cache)
8165 struct btrfs_space_info *sinfo = cache->space_info;
8170 spin_lock(&sinfo->lock);
8171 spin_lock(&cache->lock);
8172 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
8173 cache->bytes_super - btrfs_block_group_used(&cache->item);
8174 sinfo->bytes_readonly -= num_bytes;
8176 spin_unlock(&cache->lock);
8177 spin_unlock(&sinfo->lock);
8182 * checks to see if its even possible to relocate this block group.
8184 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
8185 * ok to go ahead and try.
8187 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
8189 struct btrfs_block_group_cache *block_group;
8190 struct btrfs_space_info *space_info;
8191 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
8192 struct btrfs_device *device;
8196 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
8198 /* odd, couldn't find the block group, leave it alone */
8202 /* no bytes used, we're good */
8203 if (!btrfs_block_group_used(&block_group->item))
8206 space_info = block_group->space_info;
8207 spin_lock(&space_info->lock);
8209 full = space_info->full;
8212 * if this is the last block group we have in this space, we can't
8213 * relocate it unless we're able to allocate a new chunk below.
8215 * Otherwise, we need to make sure we have room in the space to handle
8216 * all of the extents from this block group. If we can, we're good
8218 if ((space_info->total_bytes != block_group->key.offset) &&
8219 (space_info->bytes_used + space_info->bytes_reserved +
8220 space_info->bytes_pinned + space_info->bytes_readonly +
8221 btrfs_block_group_used(&block_group->item) <
8222 space_info->total_bytes)) {
8223 spin_unlock(&space_info->lock);
8226 spin_unlock(&space_info->lock);
8229 * ok we don't have enough space, but maybe we have free space on our
8230 * devices to allocate new chunks for relocation, so loop through our
8231 * alloc devices and guess if we have enough space. However, if we
8232 * were marked as full, then we know there aren't enough chunks, and we
8239 mutex_lock(&root->fs_info->chunk_mutex);
8240 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
8241 u64 min_free = btrfs_block_group_used(&block_group->item);
8245 * check to make sure we can actually find a chunk with enough
8246 * space to fit our block group in.
8248 if (device->total_bytes > device->bytes_used + min_free) {
8249 ret = find_free_dev_extent(NULL, device, min_free,
8256 mutex_unlock(&root->fs_info->chunk_mutex);
8258 btrfs_put_block_group(block_group);
8262 static int find_first_block_group(struct btrfs_root *root,
8263 struct btrfs_path *path, struct btrfs_key *key)
8266 struct btrfs_key found_key;
8267 struct extent_buffer *leaf;
8270 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
8275 slot = path->slots[0];
8276 leaf = path->nodes[0];
8277 if (slot >= btrfs_header_nritems(leaf)) {
8278 ret = btrfs_next_leaf(root, path);
8285 btrfs_item_key_to_cpu(leaf, &found_key, slot);
8287 if (found_key.objectid >= key->objectid &&
8288 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
8298 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
8300 struct btrfs_block_group_cache *block_group;
8304 struct inode *inode;
8306 block_group = btrfs_lookup_first_block_group(info, last);
8307 while (block_group) {
8308 spin_lock(&block_group->lock);
8309 if (block_group->iref)
8311 spin_unlock(&block_group->lock);
8312 block_group = next_block_group(info->tree_root,
8322 inode = block_group->inode;
8323 block_group->iref = 0;
8324 block_group->inode = NULL;
8325 spin_unlock(&block_group->lock);
8327 last = block_group->key.objectid + block_group->key.offset;
8328 btrfs_put_block_group(block_group);
8332 int btrfs_free_block_groups(struct btrfs_fs_info *info)
8334 struct btrfs_block_group_cache *block_group;
8335 struct btrfs_space_info *space_info;
8336 struct btrfs_caching_control *caching_ctl;
8339 down_write(&info->extent_commit_sem);
8340 while (!list_empty(&info->caching_block_groups)) {
8341 caching_ctl = list_entry(info->caching_block_groups.next,
8342 struct btrfs_caching_control, list);
8343 list_del(&caching_ctl->list);
8344 put_caching_control(caching_ctl);
8346 up_write(&info->extent_commit_sem);
8348 spin_lock(&info->block_group_cache_lock);
8349 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
8350 block_group = rb_entry(n, struct btrfs_block_group_cache,
8352 rb_erase(&block_group->cache_node,
8353 &info->block_group_cache_tree);
8354 spin_unlock(&info->block_group_cache_lock);
8356 down_write(&block_group->space_info->groups_sem);
8357 list_del(&block_group->list);
8358 up_write(&block_group->space_info->groups_sem);
8360 if (block_group->cached == BTRFS_CACHE_STARTED)
8361 wait_block_group_cache_done(block_group);
8364 * We haven't cached this block group, which means we could
8365 * possibly have excluded extents on this block group.
8367 if (block_group->cached == BTRFS_CACHE_NO)
8368 free_excluded_extents(info->extent_root, block_group);
8370 btrfs_remove_free_space_cache(block_group);
8371 btrfs_put_block_group(block_group);
8373 spin_lock(&info->block_group_cache_lock);
8375 spin_unlock(&info->block_group_cache_lock);
8377 /* now that all the block groups are freed, go through and
8378 * free all the space_info structs. This is only called during
8379 * the final stages of unmount, and so we know nobody is
8380 * using them. We call synchronize_rcu() once before we start,
8381 * just to be on the safe side.
8385 release_global_block_rsv(info);
8387 while(!list_empty(&info->space_info)) {
8388 space_info = list_entry(info->space_info.next,
8389 struct btrfs_space_info,
8391 if (space_info->bytes_pinned > 0 ||
8392 space_info->bytes_reserved > 0) {
8394 dump_space_info(space_info, 0, 0);
8396 list_del(&space_info->list);
8402 static void __link_block_group(struct btrfs_space_info *space_info,
8403 struct btrfs_block_group_cache *cache)
8405 int index = get_block_group_index(cache);
8407 down_write(&space_info->groups_sem);
8408 list_add_tail(&cache->list, &space_info->block_groups[index]);
8409 up_write(&space_info->groups_sem);
8412 int btrfs_read_block_groups(struct btrfs_root *root)
8414 struct btrfs_path *path;
8416 struct btrfs_block_group_cache *cache;
8417 struct btrfs_fs_info *info = root->fs_info;
8418 struct btrfs_space_info *space_info;
8419 struct btrfs_key key;
8420 struct btrfs_key found_key;
8421 struct extent_buffer *leaf;
8425 root = info->extent_root;
8428 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
8429 path = btrfs_alloc_path();
8433 cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy);
8434 if (cache_gen != 0 &&
8435 btrfs_super_generation(&root->fs_info->super_copy) != cache_gen)
8437 if (btrfs_test_opt(root, CLEAR_CACHE))
8439 if (!btrfs_test_opt(root, SPACE_CACHE) && cache_gen)
8440 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
8443 ret = find_first_block_group(root, path, &key);
8448 leaf = path->nodes[0];
8449 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
8450 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8456 atomic_set(&cache->count, 1);
8457 spin_lock_init(&cache->lock);
8458 spin_lock_init(&cache->tree_lock);
8459 cache->fs_info = info;
8460 INIT_LIST_HEAD(&cache->list);
8461 INIT_LIST_HEAD(&cache->cluster_list);
8464 cache->disk_cache_state = BTRFS_DC_CLEAR;
8467 * we only want to have 32k of ram per block group for keeping
8468 * track of free space, and if we pass 1/2 of that we want to
8469 * start converting things over to using bitmaps
8471 cache->extents_thresh = ((1024 * 32) / 2) /
8472 sizeof(struct btrfs_free_space);
8474 read_extent_buffer(leaf, &cache->item,
8475 btrfs_item_ptr_offset(leaf, path->slots[0]),
8476 sizeof(cache->item));
8477 memcpy(&cache->key, &found_key, sizeof(found_key));
8479 key.objectid = found_key.objectid + found_key.offset;
8480 btrfs_release_path(root, path);
8481 cache->flags = btrfs_block_group_flags(&cache->item);
8482 cache->sectorsize = root->sectorsize;
8485 * We need to exclude the super stripes now so that the space
8486 * info has super bytes accounted for, otherwise we'll think
8487 * we have more space than we actually do.
8489 exclude_super_stripes(root, cache);
8492 * check for two cases, either we are full, and therefore
8493 * don't need to bother with the caching work since we won't
8494 * find any space, or we are empty, and we can just add all
8495 * the space in and be done with it. This saves us _alot_ of
8496 * time, particularly in the full case.
8498 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
8499 cache->last_byte_to_unpin = (u64)-1;
8500 cache->cached = BTRFS_CACHE_FINISHED;
8501 free_excluded_extents(root, cache);
8502 } else if (btrfs_block_group_used(&cache->item) == 0) {
8503 cache->last_byte_to_unpin = (u64)-1;
8504 cache->cached = BTRFS_CACHE_FINISHED;
8505 add_new_free_space(cache, root->fs_info,
8507 found_key.objectid +
8509 free_excluded_extents(root, cache);
8512 ret = update_space_info(info, cache->flags, found_key.offset,
8513 btrfs_block_group_used(&cache->item),
8516 cache->space_info = space_info;
8517 spin_lock(&cache->space_info->lock);
8518 cache->space_info->bytes_readonly += cache->bytes_super;
8519 spin_unlock(&cache->space_info->lock);
8521 __link_block_group(space_info, cache);
8523 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8526 set_avail_alloc_bits(root->fs_info, cache->flags);
8527 if (btrfs_chunk_readonly(root, cache->key.objectid))
8528 set_block_group_ro(cache);
8531 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
8532 if (!(get_alloc_profile(root, space_info->flags) &
8533 (BTRFS_BLOCK_GROUP_RAID10 |
8534 BTRFS_BLOCK_GROUP_RAID1 |
8535 BTRFS_BLOCK_GROUP_DUP)))
8538 * avoid allocating from un-mirrored block group if there are
8539 * mirrored block groups.
8541 list_for_each_entry(cache, &space_info->block_groups[3], list)
8542 set_block_group_ro(cache);
8543 list_for_each_entry(cache, &space_info->block_groups[4], list)
8544 set_block_group_ro(cache);
8547 init_global_block_rsv(info);
8550 btrfs_free_path(path);
8554 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
8555 struct btrfs_root *root, u64 bytes_used,
8556 u64 type, u64 chunk_objectid, u64 chunk_offset,
8560 struct btrfs_root *extent_root;
8561 struct btrfs_block_group_cache *cache;
8563 extent_root = root->fs_info->extent_root;
8565 root->fs_info->last_trans_log_full_commit = trans->transid;
8567 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8571 cache->key.objectid = chunk_offset;
8572 cache->key.offset = size;
8573 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
8574 cache->sectorsize = root->sectorsize;
8575 cache->fs_info = root->fs_info;
8578 * we only want to have 32k of ram per block group for keeping track
8579 * of free space, and if we pass 1/2 of that we want to start
8580 * converting things over to using bitmaps
8582 cache->extents_thresh = ((1024 * 32) / 2) /
8583 sizeof(struct btrfs_free_space);
8584 atomic_set(&cache->count, 1);
8585 spin_lock_init(&cache->lock);
8586 spin_lock_init(&cache->tree_lock);
8587 INIT_LIST_HEAD(&cache->list);
8588 INIT_LIST_HEAD(&cache->cluster_list);
8590 btrfs_set_block_group_used(&cache->item, bytes_used);
8591 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
8592 cache->flags = type;
8593 btrfs_set_block_group_flags(&cache->item, type);
8595 cache->last_byte_to_unpin = (u64)-1;
8596 cache->cached = BTRFS_CACHE_FINISHED;
8597 exclude_super_stripes(root, cache);
8599 add_new_free_space(cache, root->fs_info, chunk_offset,
8600 chunk_offset + size);
8602 free_excluded_extents(root, cache);
8604 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
8605 &cache->space_info);
8608 spin_lock(&cache->space_info->lock);
8609 cache->space_info->bytes_readonly += cache->bytes_super;
8610 spin_unlock(&cache->space_info->lock);
8612 __link_block_group(cache->space_info, cache);
8614 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8617 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
8618 sizeof(cache->item));
8621 set_avail_alloc_bits(extent_root->fs_info, type);
8626 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
8627 struct btrfs_root *root, u64 group_start)
8629 struct btrfs_path *path;
8630 struct btrfs_block_group_cache *block_group;
8631 struct btrfs_free_cluster *cluster;
8632 struct btrfs_root *tree_root = root->fs_info->tree_root;
8633 struct btrfs_key key;
8634 struct inode *inode;
8638 root = root->fs_info->extent_root;
8640 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
8641 BUG_ON(!block_group);
8642 BUG_ON(!block_group->ro);
8644 memcpy(&key, &block_group->key, sizeof(key));
8645 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
8646 BTRFS_BLOCK_GROUP_RAID1 |
8647 BTRFS_BLOCK_GROUP_RAID10))
8652 /* make sure this block group isn't part of an allocation cluster */
8653 cluster = &root->fs_info->data_alloc_cluster;
8654 spin_lock(&cluster->refill_lock);
8655 btrfs_return_cluster_to_free_space(block_group, cluster);
8656 spin_unlock(&cluster->refill_lock);
8659 * make sure this block group isn't part of a metadata
8660 * allocation cluster
8662 cluster = &root->fs_info->meta_alloc_cluster;
8663 spin_lock(&cluster->refill_lock);
8664 btrfs_return_cluster_to_free_space(block_group, cluster);
8665 spin_unlock(&cluster->refill_lock);
8667 path = btrfs_alloc_path();
8670 inode = lookup_free_space_inode(root, block_group, path);
8671 if (!IS_ERR(inode)) {
8672 btrfs_orphan_add(trans, inode);
8674 /* One for the block groups ref */
8675 spin_lock(&block_group->lock);
8676 if (block_group->iref) {
8677 block_group->iref = 0;
8678 block_group->inode = NULL;
8679 spin_unlock(&block_group->lock);
8682 spin_unlock(&block_group->lock);
8684 /* One for our lookup ref */
8688 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
8689 key.offset = block_group->key.objectid;
8692 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
8696 btrfs_release_path(tree_root, path);
8698 ret = btrfs_del_item(trans, tree_root, path);
8701 btrfs_release_path(tree_root, path);
8704 spin_lock(&root->fs_info->block_group_cache_lock);
8705 rb_erase(&block_group->cache_node,
8706 &root->fs_info->block_group_cache_tree);
8707 spin_unlock(&root->fs_info->block_group_cache_lock);
8709 down_write(&block_group->space_info->groups_sem);
8711 * we must use list_del_init so people can check to see if they
8712 * are still on the list after taking the semaphore
8714 list_del_init(&block_group->list);
8715 up_write(&block_group->space_info->groups_sem);
8717 if (block_group->cached == BTRFS_CACHE_STARTED)
8718 wait_block_group_cache_done(block_group);
8720 btrfs_remove_free_space_cache(block_group);
8722 spin_lock(&block_group->space_info->lock);
8723 block_group->space_info->total_bytes -= block_group->key.offset;
8724 block_group->space_info->bytes_readonly -= block_group->key.offset;
8725 block_group->space_info->disk_total -= block_group->key.offset * factor;
8726 spin_unlock(&block_group->space_info->lock);
8728 memcpy(&key, &block_group->key, sizeof(key));
8730 btrfs_clear_space_info_full(root->fs_info);
8732 btrfs_put_block_group(block_group);
8733 btrfs_put_block_group(block_group);
8735 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8741 ret = btrfs_del_item(trans, root, path);
8743 btrfs_free_path(path);
8747 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
8749 return unpin_extent_range(root, start, end);
8752 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
8755 return btrfs_discard_extent(root, bytenr, num_bytes);