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>
26 #include "print-tree.h"
27 #include "transaction.h"
30 #include "ref-cache.h"
32 #define BLOCK_GROUP_DATA EXTENT_WRITEBACK
33 #define BLOCK_GROUP_METADATA EXTENT_UPTODATE
34 #define BLOCK_GROUP_SYSTEM EXTENT_NEW
36 #define BLOCK_GROUP_DIRTY EXTENT_DIRTY
38 static int finish_current_insert(struct btrfs_trans_handle *trans, struct
39 btrfs_root *extent_root);
40 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
41 btrfs_root *extent_root);
42 static struct btrfs_block_group_cache *
43 __btrfs_find_block_group(struct btrfs_root *root,
44 struct btrfs_block_group_cache *hint,
45 u64 search_start, int data, int owner);
47 void maybe_lock_mutex(struct btrfs_root *root)
49 if (root != root->fs_info->extent_root &&
50 root != root->fs_info->chunk_root &&
51 root != root->fs_info->dev_root) {
52 mutex_lock(&root->fs_info->alloc_mutex);
56 void maybe_unlock_mutex(struct btrfs_root *root)
58 if (root != root->fs_info->extent_root &&
59 root != root->fs_info->chunk_root &&
60 root != root->fs_info->dev_root) {
61 mutex_unlock(&root->fs_info->alloc_mutex);
65 static int cache_block_group(struct btrfs_root *root,
66 struct btrfs_block_group_cache *block_group)
68 struct btrfs_path *path;
71 struct extent_buffer *leaf;
72 struct extent_io_tree *free_space_cache;
82 root = root->fs_info->extent_root;
83 free_space_cache = &root->fs_info->free_space_cache;
85 if (block_group->cached)
88 path = btrfs_alloc_path();
94 * we get into deadlocks with paths held by callers of this function.
95 * since the alloc_mutex is protecting things right now, just
96 * skip the locking here
98 path->skip_locking = 1;
99 first_free = block_group->key.objectid;
100 key.objectid = block_group->key.objectid;
102 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
103 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
106 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
110 leaf = path->nodes[0];
111 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
112 if (key.objectid + key.offset > first_free)
113 first_free = key.objectid + key.offset;
116 leaf = path->nodes[0];
117 slot = path->slots[0];
118 if (slot >= btrfs_header_nritems(leaf)) {
119 ret = btrfs_next_leaf(root, path);
128 btrfs_item_key_to_cpu(leaf, &key, slot);
129 if (key.objectid < block_group->key.objectid) {
132 if (key.objectid >= block_group->key.objectid +
133 block_group->key.offset) {
137 if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
142 if (key.objectid > last) {
143 hole_size = key.objectid - last;
144 set_extent_dirty(free_space_cache, last,
145 last + hole_size - 1,
148 last = key.objectid + key.offset;
156 if (block_group->key.objectid +
157 block_group->key.offset > last) {
158 hole_size = block_group->key.objectid +
159 block_group->key.offset - last;
160 set_extent_dirty(free_space_cache, last,
161 last + hole_size - 1, GFP_NOFS);
163 block_group->cached = 1;
165 btrfs_free_path(path);
169 struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct
173 struct extent_io_tree *block_group_cache;
174 struct btrfs_block_group_cache *block_group = NULL;
180 bytenr = max_t(u64, bytenr,
181 BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
182 block_group_cache = &info->block_group_cache;
183 ret = find_first_extent_bit(block_group_cache,
184 bytenr, &start, &end,
185 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
190 ret = get_state_private(block_group_cache, start, &ptr);
194 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
198 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
202 struct extent_io_tree *block_group_cache;
203 struct btrfs_block_group_cache *block_group = NULL;
209 bytenr = max_t(u64, bytenr,
210 BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
211 block_group_cache = &info->block_group_cache;
212 ret = find_first_extent_bit(block_group_cache,
213 bytenr, &start, &end,
214 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
219 ret = get_state_private(block_group_cache, start, &ptr);
223 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
224 if (block_group->key.objectid <= bytenr && bytenr <
225 block_group->key.objectid + block_group->key.offset)
230 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
232 return (cache->flags & bits) == bits;
235 static int noinline find_search_start(struct btrfs_root *root,
236 struct btrfs_block_group_cache **cache_ret,
237 u64 *start_ret, u64 num, int data)
240 struct btrfs_block_group_cache *cache = *cache_ret;
241 struct extent_io_tree *free_space_cache;
242 struct extent_state *state;
247 u64 search_start = *start_ret;
250 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
251 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
252 free_space_cache = &root->fs_info->free_space_cache;
258 ret = cache_block_group(root, cache);
263 last = max(search_start, cache->key.objectid);
264 if (!block_group_bits(cache, data) || cache->ro)
267 spin_lock_irq(&free_space_cache->lock);
268 state = find_first_extent_bit_state(free_space_cache, last, EXTENT_DIRTY);
273 spin_unlock_irq(&free_space_cache->lock);
277 start = max(last, state->start);
278 last = state->end + 1;
279 if (last - start < num) {
281 state = extent_state_next(state);
282 } while(state && !(state->state & EXTENT_DIRTY));
285 spin_unlock_irq(&free_space_cache->lock);
289 if (start + num > cache->key.objectid + cache->key.offset)
291 if (!block_group_bits(cache, data)) {
292 printk("block group bits don't match %Lu %d\n", cache->flags, data);
298 cache = btrfs_lookup_block_group(root->fs_info, search_start);
300 printk("Unable to find block group for %Lu\n", search_start);
306 last = cache->key.objectid + cache->key.offset;
308 cache = btrfs_lookup_first_block_group(root->fs_info, last);
309 if (!cache || cache->key.objectid >= total_fs_bytes) {
318 if (cache_miss && !cache->cached) {
319 cache_block_group(root, cache);
321 cache = btrfs_lookup_first_block_group(root->fs_info, last);
324 cache = btrfs_find_block_group(root, cache, last, data, 0);
331 static u64 div_factor(u64 num, int factor)
340 static int block_group_state_bits(u64 flags)
343 if (flags & BTRFS_BLOCK_GROUP_DATA)
344 bits |= BLOCK_GROUP_DATA;
345 if (flags & BTRFS_BLOCK_GROUP_METADATA)
346 bits |= BLOCK_GROUP_METADATA;
347 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
348 bits |= BLOCK_GROUP_SYSTEM;
352 static struct btrfs_block_group_cache *
353 __btrfs_find_block_group(struct btrfs_root *root,
354 struct btrfs_block_group_cache *hint,
355 u64 search_start, int data, int owner)
357 struct btrfs_block_group_cache *cache;
358 struct extent_io_tree *block_group_cache;
359 struct btrfs_block_group_cache *found_group = NULL;
360 struct btrfs_fs_info *info = root->fs_info;
373 block_group_cache = &info->block_group_cache;
375 if (data & BTRFS_BLOCK_GROUP_METADATA)
378 bit = block_group_state_bits(data);
381 struct btrfs_block_group_cache *shint;
382 shint = btrfs_lookup_first_block_group(info, search_start);
383 if (shint && block_group_bits(shint, data) && !shint->ro) {
384 spin_lock(&shint->lock);
385 used = btrfs_block_group_used(&shint->item);
386 if (used + shint->pinned <
387 div_factor(shint->key.offset, factor)) {
388 spin_unlock(&shint->lock);
391 spin_unlock(&shint->lock);
394 if (hint && !hint->ro && block_group_bits(hint, data)) {
395 spin_lock(&hint->lock);
396 used = btrfs_block_group_used(&hint->item);
397 if (used + hint->pinned <
398 div_factor(hint->key.offset, factor)) {
399 spin_unlock(&hint->lock);
402 spin_unlock(&hint->lock);
403 last = hint->key.objectid + hint->key.offset;
406 last = max(hint->key.objectid, search_start);
412 ret = find_first_extent_bit(block_group_cache, last,
417 ret = get_state_private(block_group_cache, start, &ptr);
423 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
424 spin_lock(&cache->lock);
425 last = cache->key.objectid + cache->key.offset;
426 used = btrfs_block_group_used(&cache->item);
428 if (!cache->ro && block_group_bits(cache, data)) {
429 free_check = div_factor(cache->key.offset, factor);
430 if (used + cache->pinned < free_check) {
432 spin_unlock(&cache->lock);
436 spin_unlock(&cache->lock);
444 if (!full_search && factor < 10) {
454 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
455 struct btrfs_block_group_cache
456 *hint, u64 search_start,
460 struct btrfs_block_group_cache *ret;
461 ret = __btrfs_find_block_group(root, hint, search_start, data, owner);
464 static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation,
465 u64 owner, u64 owner_offset)
467 u32 high_crc = ~(u32)0;
468 u32 low_crc = ~(u32)0;
470 lenum = cpu_to_le64(root_objectid);
471 high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
472 lenum = cpu_to_le64(ref_generation);
473 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
474 if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
475 lenum = cpu_to_le64(owner);
476 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
477 lenum = cpu_to_le64(owner_offset);
478 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
480 return ((u64)high_crc << 32) | (u64)low_crc;
483 static int match_extent_ref(struct extent_buffer *leaf,
484 struct btrfs_extent_ref *disk_ref,
485 struct btrfs_extent_ref *cpu_ref)
490 if (cpu_ref->objectid)
491 len = sizeof(*cpu_ref);
493 len = 2 * sizeof(u64);
494 ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref,
499 /* simple helper to search for an existing extent at a given offset */
500 int btrfs_lookup_extent(struct btrfs_root *root, struct btrfs_path *path,
504 struct btrfs_key key;
506 maybe_lock_mutex(root);
507 key.objectid = start;
509 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
510 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
512 maybe_unlock_mutex(root);
516 static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans,
517 struct btrfs_root *root,
518 struct btrfs_path *path, u64 bytenr,
520 u64 ref_generation, u64 owner,
521 u64 owner_offset, int del)
524 struct btrfs_key key;
525 struct btrfs_key found_key;
526 struct btrfs_extent_ref ref;
527 struct extent_buffer *leaf;
528 struct btrfs_extent_ref *disk_ref;
532 btrfs_set_stack_ref_root(&ref, root_objectid);
533 btrfs_set_stack_ref_generation(&ref, ref_generation);
534 btrfs_set_stack_ref_objectid(&ref, owner);
535 btrfs_set_stack_ref_offset(&ref, owner_offset);
537 hash = hash_extent_ref(root_objectid, ref_generation, owner,
540 key.objectid = bytenr;
541 key.type = BTRFS_EXTENT_REF_KEY;
544 ret = btrfs_search_slot(trans, root, &key, path,
548 leaf = path->nodes[0];
550 u32 nritems = btrfs_header_nritems(leaf);
551 if (path->slots[0] >= nritems) {
552 ret2 = btrfs_next_leaf(root, path);
555 leaf = path->nodes[0];
557 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
558 if (found_key.objectid != bytenr ||
559 found_key.type != BTRFS_EXTENT_REF_KEY)
561 key.offset = found_key.offset;
563 btrfs_release_path(root, path);
567 disk_ref = btrfs_item_ptr(path->nodes[0],
569 struct btrfs_extent_ref);
570 if (match_extent_ref(path->nodes[0], disk_ref, &ref)) {
574 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
575 key.offset = found_key.offset + 1;
576 btrfs_release_path(root, path);
583 * Back reference rules. Back refs have three main goals:
585 * 1) differentiate between all holders of references to an extent so that
586 * when a reference is dropped we can make sure it was a valid reference
587 * before freeing the extent.
589 * 2) Provide enough information to quickly find the holders of an extent
590 * if we notice a given block is corrupted or bad.
592 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
593 * maintenance. This is actually the same as #2, but with a slightly
594 * different use case.
596 * File extents can be referenced by:
598 * - multiple snapshots, subvolumes, or different generations in one subvol
599 * - different files inside a single subvolume (in theory, not implemented yet)
600 * - different offsets inside a file (bookend extents in file.c)
602 * The extent ref structure has fields for:
604 * - Objectid of the subvolume root
605 * - Generation number of the tree holding the reference
606 * - objectid of the file holding the reference
607 * - offset in the file corresponding to the key holding the reference
609 * When a file extent is allocated the fields are filled in:
610 * (root_key.objectid, trans->transid, inode objectid, offset in file)
612 * When a leaf is cow'd new references are added for every file extent found
613 * in the leaf. It looks the same as the create case, but trans->transid
614 * will be different when the block is cow'd.
616 * (root_key.objectid, trans->transid, inode objectid, offset in file)
618 * When a file extent is removed either during snapshot deletion or file
619 * truncation, the corresponding back reference is found
622 * (btrfs_header_owner(leaf), btrfs_header_generation(leaf),
623 * inode objectid, offset in file)
625 * Btree extents can be referenced by:
627 * - Different subvolumes
628 * - Different generations of the same subvolume
630 * Storing sufficient information for a full reverse mapping of a btree
631 * block would require storing the lowest key of the block in the backref,
632 * and it would require updating that lowest key either before write out or
633 * every time it changed. Instead, the objectid of the lowest key is stored
634 * along with the level of the tree block. This provides a hint
635 * about where in the btree the block can be found. Searches through the
636 * btree only need to look for a pointer to that block, so they stop one
637 * level higher than the level recorded in the backref.
639 * Some btrees do not do reference counting on their extents. These
640 * include the extent tree and the tree of tree roots. Backrefs for these
641 * trees always have a generation of zero.
643 * When a tree block is created, back references are inserted:
645 * (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid)
647 * When a tree block is cow'd in a reference counted root,
648 * new back references are added for all the blocks it points to.
649 * These are of the form (trans->transid will have increased since creation):
651 * (root->root_key.objectid, trans->transid, level, lowest_key_objectid)
653 * Because the lowest_key_objectid and the level are just hints
654 * they are not used when backrefs are deleted. When a backref is deleted:
656 * if backref was for a tree root:
657 * root_objectid = root->root_key.objectid
659 * root_objectid = btrfs_header_owner(parent)
661 * (root_objectid, btrfs_header_generation(parent) or zero, 0, 0)
663 * Back Reference Key hashing:
665 * Back references have four fields, each 64 bits long. Unfortunately,
666 * This is hashed into a single 64 bit number and placed into the key offset.
667 * The key objectid corresponds to the first byte in the extent, and the
668 * key type is set to BTRFS_EXTENT_REF_KEY
670 int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans,
671 struct btrfs_root *root,
672 struct btrfs_path *path, u64 bytenr,
673 u64 root_objectid, u64 ref_generation,
674 u64 owner, u64 owner_offset)
677 struct btrfs_key key;
678 struct btrfs_extent_ref ref;
679 struct btrfs_extent_ref *disk_ref;
682 btrfs_set_stack_ref_root(&ref, root_objectid);
683 btrfs_set_stack_ref_generation(&ref, ref_generation);
684 btrfs_set_stack_ref_objectid(&ref, owner);
685 btrfs_set_stack_ref_offset(&ref, owner_offset);
687 hash = hash_extent_ref(root_objectid, ref_generation, owner,
690 key.objectid = bytenr;
691 key.type = BTRFS_EXTENT_REF_KEY;
693 ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref));
694 while (ret == -EEXIST) {
695 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
696 struct btrfs_extent_ref);
697 if (match_extent_ref(path->nodes[0], disk_ref, &ref))
700 btrfs_release_path(root, path);
701 ret = btrfs_insert_empty_item(trans, root, path, &key,
706 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
707 struct btrfs_extent_ref);
708 write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref,
710 btrfs_mark_buffer_dirty(path->nodes[0]);
712 btrfs_release_path(root, path);
716 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
717 struct btrfs_root *root,
718 u64 bytenr, u64 num_bytes,
719 u64 root_objectid, u64 ref_generation,
720 u64 owner, u64 owner_offset)
722 struct btrfs_path *path;
724 struct btrfs_key key;
725 struct extent_buffer *l;
726 struct btrfs_extent_item *item;
729 WARN_ON(num_bytes < root->sectorsize);
730 path = btrfs_alloc_path();
735 key.objectid = bytenr;
736 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
737 key.offset = num_bytes;
738 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
747 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
748 refs = btrfs_extent_refs(l, item);
749 btrfs_set_extent_refs(l, item, refs + 1);
750 btrfs_mark_buffer_dirty(path->nodes[0]);
752 btrfs_release_path(root->fs_info->extent_root, path);
755 ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root,
756 path, bytenr, root_objectid,
757 ref_generation, owner, owner_offset);
759 finish_current_insert(trans, root->fs_info->extent_root);
760 del_pending_extents(trans, root->fs_info->extent_root);
762 btrfs_free_path(path);
766 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
767 struct btrfs_root *root,
768 u64 bytenr, u64 num_bytes,
769 u64 root_objectid, u64 ref_generation,
770 u64 owner, u64 owner_offset)
774 mutex_lock(&root->fs_info->alloc_mutex);
775 ret = __btrfs_inc_extent_ref(trans, root, bytenr, num_bytes,
776 root_objectid, ref_generation,
777 owner, owner_offset);
778 mutex_unlock(&root->fs_info->alloc_mutex);
782 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
783 struct btrfs_root *root)
785 finish_current_insert(trans, root->fs_info->extent_root);
786 del_pending_extents(trans, root->fs_info->extent_root);
790 static int lookup_extent_ref(struct btrfs_trans_handle *trans,
791 struct btrfs_root *root, u64 bytenr,
792 u64 num_bytes, u32 *refs)
794 struct btrfs_path *path;
796 struct btrfs_key key;
797 struct extent_buffer *l;
798 struct btrfs_extent_item *item;
800 WARN_ON(num_bytes < root->sectorsize);
801 path = btrfs_alloc_path();
803 key.objectid = bytenr;
804 key.offset = num_bytes;
805 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
806 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
811 btrfs_print_leaf(root, path->nodes[0]);
812 printk("failed to find block number %Lu\n", bytenr);
816 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
817 *refs = btrfs_extent_refs(l, item);
819 btrfs_free_path(path);
824 static int get_reference_status(struct btrfs_root *root, u64 bytenr,
825 u64 parent_gen, u64 ref_objectid,
826 u64 *min_generation, u32 *ref_count)
828 struct btrfs_root *extent_root = root->fs_info->extent_root;
829 struct btrfs_path *path;
830 struct extent_buffer *leaf;
831 struct btrfs_extent_ref *ref_item;
832 struct btrfs_key key;
833 struct btrfs_key found_key;
834 u64 root_objectid = root->root_key.objectid;
839 key.objectid = bytenr;
841 key.type = BTRFS_EXTENT_ITEM_KEY;
843 path = btrfs_alloc_path();
844 mutex_lock(&root->fs_info->alloc_mutex);
845 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
850 leaf = path->nodes[0];
851 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
853 if (found_key.objectid != bytenr ||
854 found_key.type != BTRFS_EXTENT_ITEM_KEY) {
860 *min_generation = (u64)-1;
863 leaf = path->nodes[0];
864 nritems = btrfs_header_nritems(leaf);
865 if (path->slots[0] >= nritems) {
866 ret = btrfs_next_leaf(extent_root, path);
873 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
874 if (found_key.objectid != bytenr)
877 if (found_key.type != BTRFS_EXTENT_REF_KEY) {
882 ref_item = btrfs_item_ptr(leaf, path->slots[0],
883 struct btrfs_extent_ref);
884 ref_generation = btrfs_ref_generation(leaf, ref_item);
886 * For (parent_gen > 0 && parent_gen > ref_gen):
888 * we reach here through the oldest root, therefore
889 * all other reference from same snapshot should have
890 * a larger generation.
892 if ((root_objectid != btrfs_ref_root(leaf, ref_item)) ||
893 (parent_gen > 0 && parent_gen > ref_generation) ||
894 (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID &&
895 ref_objectid != btrfs_ref_objectid(leaf, ref_item))) {
902 if (*min_generation > ref_generation)
903 *min_generation = ref_generation;
909 mutex_unlock(&root->fs_info->alloc_mutex);
910 btrfs_free_path(path);
914 int btrfs_cross_ref_exists(struct btrfs_trans_handle *trans,
915 struct btrfs_root *root,
916 struct btrfs_key *key, u64 bytenr)
918 struct btrfs_root *old_root;
919 struct btrfs_path *path = NULL;
920 struct extent_buffer *eb;
921 struct btrfs_file_extent_item *item;
929 BUG_ON(trans == NULL);
930 BUG_ON(key->type != BTRFS_EXTENT_DATA_KEY);
931 ret = get_reference_status(root, bytenr, 0, key->objectid,
932 &min_generation, &ref_count);
939 old_root = root->dirty_root->root;
940 ref_generation = old_root->root_key.offset;
942 /* all references are created in running transaction */
943 if (min_generation > ref_generation) {
948 path = btrfs_alloc_path();
954 path->skip_locking = 1;
955 /* if no item found, the extent is referenced by other snapshot */
956 ret = btrfs_search_slot(NULL, old_root, key, path, 0, 0);
961 item = btrfs_item_ptr(eb, path->slots[0],
962 struct btrfs_file_extent_item);
963 if (btrfs_file_extent_type(eb, item) != BTRFS_FILE_EXTENT_REG ||
964 btrfs_file_extent_disk_bytenr(eb, item) != bytenr) {
969 for (level = BTRFS_MAX_LEVEL - 1; level >= -1; level--) {
971 eb = path->nodes[level];
974 extent_start = eb->start;
976 extent_start = bytenr;
978 ret = get_reference_status(root, extent_start, ref_generation,
979 0, &min_generation, &ref_count);
983 if (ref_count != 1) {
988 ref_generation = btrfs_header_generation(eb);
993 btrfs_free_path(path);
997 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
998 struct extent_buffer *buf, int cache_ref)
1002 struct btrfs_key key;
1003 struct btrfs_file_extent_item *fi;
1008 int nr_file_extents = 0;
1010 if (!root->ref_cows)
1013 level = btrfs_header_level(buf);
1014 nritems = btrfs_header_nritems(buf);
1015 for (i = 0; i < nritems; i++) {
1019 btrfs_item_key_to_cpu(buf, &key, i);
1020 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
1022 fi = btrfs_item_ptr(buf, i,
1023 struct btrfs_file_extent_item);
1024 if (btrfs_file_extent_type(buf, fi) ==
1025 BTRFS_FILE_EXTENT_INLINE)
1027 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
1028 if (disk_bytenr == 0)
1031 if (buf != root->commit_root)
1034 mutex_lock(&root->fs_info->alloc_mutex);
1035 ret = __btrfs_inc_extent_ref(trans, root, disk_bytenr,
1036 btrfs_file_extent_disk_num_bytes(buf, fi),
1037 root->root_key.objectid, trans->transid,
1038 key.objectid, key.offset);
1039 mutex_unlock(&root->fs_info->alloc_mutex);
1046 bytenr = btrfs_node_blockptr(buf, i);
1047 btrfs_node_key_to_cpu(buf, &key, i);
1049 mutex_lock(&root->fs_info->alloc_mutex);
1050 ret = __btrfs_inc_extent_ref(trans, root, bytenr,
1051 btrfs_level_size(root, level - 1),
1052 root->root_key.objectid,
1054 level - 1, key.objectid);
1055 mutex_unlock(&root->fs_info->alloc_mutex);
1063 /* cache orignal leaf block's references */
1064 if (level == 0 && cache_ref && buf != root->commit_root) {
1065 struct btrfs_leaf_ref *ref;
1066 struct btrfs_extent_info *info;
1068 ref = btrfs_alloc_leaf_ref(root, nr_file_extents);
1074 ref->root_gen = root->root_key.offset;
1075 ref->bytenr = buf->start;
1076 ref->owner = btrfs_header_owner(buf);
1077 ref->generation = btrfs_header_generation(buf);
1078 ref->nritems = nr_file_extents;
1079 info = ref->extents;
1081 for (i = 0; nr_file_extents > 0 && i < nritems; i++) {
1083 btrfs_item_key_to_cpu(buf, &key, i);
1084 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
1086 fi = btrfs_item_ptr(buf, i,
1087 struct btrfs_file_extent_item);
1088 if (btrfs_file_extent_type(buf, fi) ==
1089 BTRFS_FILE_EXTENT_INLINE)
1091 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
1092 if (disk_bytenr == 0)
1095 info->bytenr = disk_bytenr;
1097 btrfs_file_extent_disk_num_bytes(buf, fi);
1098 info->objectid = key.objectid;
1099 info->offset = key.offset;
1103 BUG_ON(!root->ref_tree);
1104 ret = btrfs_add_leaf_ref(root, ref);
1106 btrfs_free_leaf_ref(root, ref);
1113 for (i =0; i < faili; i++) {
1116 btrfs_item_key_to_cpu(buf, &key, i);
1117 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
1119 fi = btrfs_item_ptr(buf, i,
1120 struct btrfs_file_extent_item);
1121 if (btrfs_file_extent_type(buf, fi) ==
1122 BTRFS_FILE_EXTENT_INLINE)
1124 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
1125 if (disk_bytenr == 0)
1127 err = btrfs_free_extent(trans, root, disk_bytenr,
1128 btrfs_file_extent_disk_num_bytes(buf,
1132 bytenr = btrfs_node_blockptr(buf, i);
1133 err = btrfs_free_extent(trans, root, bytenr,
1134 btrfs_level_size(root, level - 1), 0);
1142 static int write_one_cache_group(struct btrfs_trans_handle *trans,
1143 struct btrfs_root *root,
1144 struct btrfs_path *path,
1145 struct btrfs_block_group_cache *cache)
1149 struct btrfs_root *extent_root = root->fs_info->extent_root;
1151 struct extent_buffer *leaf;
1153 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
1158 leaf = path->nodes[0];
1159 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
1160 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
1161 btrfs_mark_buffer_dirty(leaf);
1162 btrfs_release_path(extent_root, path);
1164 finish_current_insert(trans, extent_root);
1165 pending_ret = del_pending_extents(trans, extent_root);
1174 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
1175 struct btrfs_root *root)
1177 struct extent_io_tree *block_group_cache;
1178 struct btrfs_block_group_cache *cache;
1182 struct btrfs_path *path;
1188 block_group_cache = &root->fs_info->block_group_cache;
1189 path = btrfs_alloc_path();
1193 mutex_lock(&root->fs_info->alloc_mutex);
1195 ret = find_first_extent_bit(block_group_cache, last,
1196 &start, &end, BLOCK_GROUP_DIRTY);
1201 ret = get_state_private(block_group_cache, start, &ptr);
1204 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
1205 err = write_one_cache_group(trans, root,
1208 * if we fail to write the cache group, we want
1209 * to keep it marked dirty in hopes that a later
1216 clear_extent_bits(block_group_cache, start, end,
1217 BLOCK_GROUP_DIRTY, GFP_NOFS);
1219 btrfs_free_path(path);
1220 mutex_unlock(&root->fs_info->alloc_mutex);
1224 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
1227 struct list_head *head = &info->space_info;
1228 struct list_head *cur;
1229 struct btrfs_space_info *found;
1230 list_for_each(cur, head) {
1231 found = list_entry(cur, struct btrfs_space_info, list);
1232 if (found->flags == flags)
1239 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
1240 u64 total_bytes, u64 bytes_used,
1241 struct btrfs_space_info **space_info)
1243 struct btrfs_space_info *found;
1245 found = __find_space_info(info, flags);
1247 found->total_bytes += total_bytes;
1248 found->bytes_used += bytes_used;
1250 *space_info = found;
1253 found = kmalloc(sizeof(*found), GFP_NOFS);
1257 list_add(&found->list, &info->space_info);
1258 found->flags = flags;
1259 found->total_bytes = total_bytes;
1260 found->bytes_used = bytes_used;
1261 found->bytes_pinned = 0;
1263 found->force_alloc = 0;
1264 *space_info = found;
1268 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
1270 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
1271 BTRFS_BLOCK_GROUP_RAID1 |
1272 BTRFS_BLOCK_GROUP_RAID10 |
1273 BTRFS_BLOCK_GROUP_DUP);
1275 if (flags & BTRFS_BLOCK_GROUP_DATA)
1276 fs_info->avail_data_alloc_bits |= extra_flags;
1277 if (flags & BTRFS_BLOCK_GROUP_METADATA)
1278 fs_info->avail_metadata_alloc_bits |= extra_flags;
1279 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
1280 fs_info->avail_system_alloc_bits |= extra_flags;
1284 static u64 reduce_alloc_profile(struct btrfs_root *root, u64 flags)
1286 u64 num_devices = root->fs_info->fs_devices->num_devices;
1288 if (num_devices == 1)
1289 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
1290 if (num_devices < 4)
1291 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
1293 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
1294 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
1295 BTRFS_BLOCK_GROUP_RAID10))) {
1296 flags &= ~BTRFS_BLOCK_GROUP_DUP;
1299 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
1300 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
1301 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
1304 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
1305 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
1306 (flags & BTRFS_BLOCK_GROUP_RAID10) |
1307 (flags & BTRFS_BLOCK_GROUP_DUP)))
1308 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
1312 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
1313 struct btrfs_root *extent_root, u64 alloc_bytes,
1314 u64 flags, int force)
1316 struct btrfs_space_info *space_info;
1322 flags = reduce_alloc_profile(extent_root, flags);
1324 space_info = __find_space_info(extent_root->fs_info, flags);
1326 ret = update_space_info(extent_root->fs_info, flags,
1330 BUG_ON(!space_info);
1332 if (space_info->force_alloc) {
1334 space_info->force_alloc = 0;
1336 if (space_info->full)
1339 thresh = div_factor(space_info->total_bytes, 6);
1341 (space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
1345 mutex_lock(&extent_root->fs_info->chunk_mutex);
1346 ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
1347 if (ret == -ENOSPC) {
1348 printk("space info full %Lu\n", flags);
1349 space_info->full = 1;
1354 ret = btrfs_make_block_group(trans, extent_root, 0, flags,
1355 BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
1358 mutex_unlock(&extent_root->fs_info->chunk_mutex);
1363 static int update_block_group(struct btrfs_trans_handle *trans,
1364 struct btrfs_root *root,
1365 u64 bytenr, u64 num_bytes, int alloc,
1368 struct btrfs_block_group_cache *cache;
1369 struct btrfs_fs_info *info = root->fs_info;
1370 u64 total = num_bytes;
1376 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1378 cache = btrfs_lookup_block_group(info, bytenr);
1382 byte_in_group = bytenr - cache->key.objectid;
1383 WARN_ON(byte_in_group > cache->key.offset);
1384 start = cache->key.objectid;
1385 end = start + cache->key.offset - 1;
1386 set_extent_bits(&info->block_group_cache, start, end,
1387 BLOCK_GROUP_DIRTY, GFP_NOFS);
1389 spin_lock(&cache->lock);
1390 old_val = btrfs_block_group_used(&cache->item);
1391 num_bytes = min(total, cache->key.offset - byte_in_group);
1393 old_val += num_bytes;
1394 cache->space_info->bytes_used += num_bytes;
1395 btrfs_set_block_group_used(&cache->item, old_val);
1396 spin_unlock(&cache->lock);
1398 old_val -= num_bytes;
1399 cache->space_info->bytes_used -= num_bytes;
1400 btrfs_set_block_group_used(&cache->item, old_val);
1401 spin_unlock(&cache->lock);
1403 set_extent_dirty(&info->free_space_cache,
1404 bytenr, bytenr + num_bytes - 1,
1409 bytenr += num_bytes;
1414 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
1419 ret = find_first_extent_bit(&root->fs_info->block_group_cache,
1420 search_start, &start, &end,
1421 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
1422 BLOCK_GROUP_SYSTEM);
1429 int btrfs_update_pinned_extents(struct btrfs_root *root,
1430 u64 bytenr, u64 num, int pin)
1433 struct btrfs_block_group_cache *cache;
1434 struct btrfs_fs_info *fs_info = root->fs_info;
1436 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1438 set_extent_dirty(&fs_info->pinned_extents,
1439 bytenr, bytenr + num - 1, GFP_NOFS);
1441 clear_extent_dirty(&fs_info->pinned_extents,
1442 bytenr, bytenr + num - 1, GFP_NOFS);
1445 cache = btrfs_lookup_block_group(fs_info, bytenr);
1447 u64 first = first_logical_byte(root, bytenr);
1448 WARN_ON(first < bytenr);
1449 len = min(first - bytenr, num);
1451 len = min(num, cache->key.offset -
1452 (bytenr - cache->key.objectid));
1456 spin_lock(&cache->lock);
1457 cache->pinned += len;
1458 cache->space_info->bytes_pinned += len;
1459 spin_unlock(&cache->lock);
1461 fs_info->total_pinned += len;
1464 spin_lock(&cache->lock);
1465 cache->pinned -= len;
1466 cache->space_info->bytes_pinned -= len;
1467 spin_unlock(&cache->lock);
1469 fs_info->total_pinned -= len;
1477 int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
1482 struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
1486 ret = find_first_extent_bit(pinned_extents, last,
1487 &start, &end, EXTENT_DIRTY);
1490 set_extent_dirty(copy, start, end, GFP_NOFS);
1496 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
1497 struct btrfs_root *root,
1498 struct extent_io_tree *unpin)
1503 struct extent_io_tree *free_space_cache;
1504 free_space_cache = &root->fs_info->free_space_cache;
1506 mutex_lock(&root->fs_info->alloc_mutex);
1508 ret = find_first_extent_bit(unpin, 0, &start, &end,
1512 btrfs_update_pinned_extents(root, start, end + 1 - start, 0);
1513 clear_extent_dirty(unpin, start, end, GFP_NOFS);
1514 set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
1515 if (need_resched()) {
1516 mutex_unlock(&root->fs_info->alloc_mutex);
1518 mutex_lock(&root->fs_info->alloc_mutex);
1521 mutex_unlock(&root->fs_info->alloc_mutex);
1525 static int finish_current_insert(struct btrfs_trans_handle *trans,
1526 struct btrfs_root *extent_root)
1530 struct btrfs_fs_info *info = extent_root->fs_info;
1531 struct extent_buffer *eb;
1532 struct btrfs_path *path;
1533 struct btrfs_key ins;
1534 struct btrfs_disk_key first;
1535 struct btrfs_extent_item extent_item;
1540 WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
1541 btrfs_set_stack_extent_refs(&extent_item, 1);
1542 btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
1543 path = btrfs_alloc_path();
1546 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
1547 &end, EXTENT_LOCKED);
1551 ins.objectid = start;
1552 ins.offset = end + 1 - start;
1553 err = btrfs_insert_item(trans, extent_root, &ins,
1554 &extent_item, sizeof(extent_item));
1555 clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
1558 eb = btrfs_find_create_tree_block(extent_root, ins.objectid,
1561 if (!btrfs_buffer_uptodate(eb, trans->transid))
1562 btrfs_read_buffer(eb, trans->transid);
1564 btrfs_tree_lock(eb);
1565 level = btrfs_header_level(eb);
1567 btrfs_item_key(eb, &first, 0);
1569 btrfs_node_key(eb, &first, 0);
1571 btrfs_tree_unlock(eb);
1572 free_extent_buffer(eb);
1574 * the first key is just a hint, so the race we've created
1575 * against reading it is fine
1577 err = btrfs_insert_extent_backref(trans, extent_root, path,
1578 start, extent_root->root_key.objectid,
1580 btrfs_disk_key_objectid(&first));
1582 if (need_resched()) {
1583 mutex_unlock(&extent_root->fs_info->alloc_mutex);
1585 mutex_lock(&extent_root->fs_info->alloc_mutex);
1588 btrfs_free_path(path);
1592 static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
1593 int is_data, int pending)
1597 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1599 struct extent_buffer *buf;
1604 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
1606 /* we can reuse a block if it hasn't been written
1607 * and it is from this transaction. We can't
1608 * reuse anything from the tree log root because
1609 * it has tiny sub-transactions.
1611 if (btrfs_buffer_uptodate(buf, 0) &&
1612 btrfs_try_tree_lock(buf)) {
1614 root->fs_info->running_transaction->transid;
1615 u64 header_transid =
1616 btrfs_header_generation(buf);
1617 if (btrfs_header_owner(buf) !=
1618 BTRFS_TREE_LOG_OBJECTID &&
1619 header_transid == transid &&
1620 !btrfs_header_flag(buf,
1621 BTRFS_HEADER_FLAG_WRITTEN)) {
1622 clean_tree_block(NULL, root, buf);
1623 btrfs_tree_unlock(buf);
1624 free_extent_buffer(buf);
1627 btrfs_tree_unlock(buf);
1629 free_extent_buffer(buf);
1632 btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
1634 set_extent_bits(&root->fs_info->pending_del,
1635 bytenr, bytenr + num_bytes - 1,
1636 EXTENT_LOCKED, GFP_NOFS);
1643 * remove an extent from the root, returns 0 on success
1645 static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
1646 *root, u64 bytenr, u64 num_bytes,
1647 u64 root_objectid, u64 ref_generation,
1648 u64 owner_objectid, u64 owner_offset, int pin,
1651 struct btrfs_path *path;
1652 struct btrfs_key key;
1653 struct btrfs_fs_info *info = root->fs_info;
1654 struct btrfs_root *extent_root = info->extent_root;
1655 struct extent_buffer *leaf;
1657 int extent_slot = 0;
1658 int found_extent = 0;
1660 struct btrfs_extent_item *ei;
1663 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1664 key.objectid = bytenr;
1665 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
1666 key.offset = num_bytes;
1667 path = btrfs_alloc_path();
1672 ret = lookup_extent_backref(trans, extent_root, path,
1673 bytenr, root_objectid,
1675 owner_objectid, owner_offset, 1);
1677 struct btrfs_key found_key;
1678 extent_slot = path->slots[0];
1679 while(extent_slot > 0) {
1681 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1683 if (found_key.objectid != bytenr)
1685 if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
1686 found_key.offset == num_bytes) {
1690 if (path->slots[0] - extent_slot > 5)
1694 ret = btrfs_del_item(trans, extent_root, path);
1696 btrfs_print_leaf(extent_root, path->nodes[0]);
1698 printk("Unable to find ref byte nr %Lu root %Lu "
1699 " gen %Lu owner %Lu offset %Lu\n", bytenr,
1700 root_objectid, ref_generation, owner_objectid,
1703 if (!found_extent) {
1704 btrfs_release_path(extent_root, path);
1705 ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
1709 extent_slot = path->slots[0];
1712 leaf = path->nodes[0];
1713 ei = btrfs_item_ptr(leaf, extent_slot,
1714 struct btrfs_extent_item);
1715 refs = btrfs_extent_refs(leaf, ei);
1718 btrfs_set_extent_refs(leaf, ei, refs);
1720 btrfs_mark_buffer_dirty(leaf);
1722 if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) {
1723 /* if the back ref and the extent are next to each other
1724 * they get deleted below in one shot
1726 path->slots[0] = extent_slot;
1728 } else if (found_extent) {
1729 /* otherwise delete the extent back ref */
1730 ret = btrfs_del_item(trans, extent_root, path);
1732 /* if refs are 0, we need to setup the path for deletion */
1734 btrfs_release_path(extent_root, path);
1735 ret = btrfs_search_slot(trans, extent_root, &key, path,
1746 #ifdef BIO_RW_DISCARD
1747 u64 map_length = num_bytes;
1748 struct btrfs_multi_bio *multi = NULL;
1752 ret = pin_down_bytes(root, bytenr, num_bytes,
1753 owner_objectid >= BTRFS_FIRST_FREE_OBJECTID, 0);
1759 /* block accounting for super block */
1760 spin_lock_irq(&info->delalloc_lock);
1761 super_used = btrfs_super_bytes_used(&info->super_copy);
1762 btrfs_set_super_bytes_used(&info->super_copy,
1763 super_used - num_bytes);
1764 spin_unlock_irq(&info->delalloc_lock);
1766 /* block accounting for root item */
1767 root_used = btrfs_root_used(&root->root_item);
1768 btrfs_set_root_used(&root->root_item,
1769 root_used - num_bytes);
1770 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
1775 ret = update_block_group(trans, root, bytenr, num_bytes, 0,
1779 #ifdef BIO_RW_DISCARD
1780 /* Tell the block device(s) that the sectors can be discarded */
1781 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1782 bytenr, &map_length, &multi, 0);
1784 struct btrfs_bio_stripe *stripe = multi->stripes;
1787 if (map_length > num_bytes)
1788 map_length = num_bytes;
1790 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1791 blkdev_issue_discard(stripe->dev->bdev,
1792 stripe->physical >> 9,
1799 btrfs_free_path(path);
1800 finish_current_insert(trans, extent_root);
1805 * find all the blocks marked as pending in the radix tree and remove
1806 * them from the extent map
1808 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
1809 btrfs_root *extent_root)
1815 struct extent_io_tree *pending_del;
1816 struct extent_io_tree *pinned_extents;
1818 WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
1819 pending_del = &extent_root->fs_info->pending_del;
1820 pinned_extents = &extent_root->fs_info->pinned_extents;
1823 ret = find_first_extent_bit(pending_del, 0, &start, &end,
1827 clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
1829 if (!test_range_bit(&extent_root->fs_info->extent_ins,
1830 start, end, EXTENT_LOCKED, 0)) {
1831 btrfs_update_pinned_extents(extent_root, start,
1832 end + 1 - start, 1);
1833 ret = __free_extent(trans, extent_root,
1834 start, end + 1 - start,
1835 extent_root->root_key.objectid,
1838 clear_extent_bits(&extent_root->fs_info->extent_ins,
1839 start, end, EXTENT_LOCKED, GFP_NOFS);
1844 if (need_resched()) {
1845 mutex_unlock(&extent_root->fs_info->alloc_mutex);
1847 mutex_lock(&extent_root->fs_info->alloc_mutex);
1854 * remove an extent from the root, returns 0 on success
1856 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
1857 struct btrfs_root *root, u64 bytenr,
1858 u64 num_bytes, u64 root_objectid,
1859 u64 ref_generation, u64 owner_objectid,
1860 u64 owner_offset, int pin)
1862 struct btrfs_root *extent_root = root->fs_info->extent_root;
1866 WARN_ON(num_bytes < root->sectorsize);
1867 if (!root->ref_cows)
1870 if (root == extent_root) {
1871 pin_down_bytes(root, bytenr, num_bytes, 0, 1);
1874 /* if metadata always pin */
1875 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
1876 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
1877 /* btrfs_free_reserved_extent */
1878 set_extent_dirty(&root->fs_info->free_space_cache,
1879 bytenr, bytenr + num_bytes - 1, GFP_NOFS);
1885 /* if data pin when any transaction has committed this */
1886 if (ref_generation != trans->transid)
1889 ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid,
1890 ref_generation, owner_objectid, owner_offset,
1893 finish_current_insert(trans, root->fs_info->extent_root);
1894 pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
1895 return ret ? ret : pending_ret;
1898 int btrfs_free_extent(struct btrfs_trans_handle *trans,
1899 struct btrfs_root *root, u64 bytenr,
1900 u64 num_bytes, u64 root_objectid,
1901 u64 ref_generation, u64 owner_objectid,
1902 u64 owner_offset, int pin)
1906 maybe_lock_mutex(root);
1907 ret = __btrfs_free_extent(trans, root, bytenr, num_bytes,
1908 root_objectid, ref_generation,
1909 owner_objectid, owner_offset, pin);
1910 maybe_unlock_mutex(root);
1914 static u64 stripe_align(struct btrfs_root *root, u64 val)
1916 u64 mask = ((u64)root->stripesize - 1);
1917 u64 ret = (val + mask) & ~mask;
1922 * walks the btree of allocated extents and find a hole of a given size.
1923 * The key ins is changed to record the hole:
1924 * ins->objectid == block start
1925 * ins->flags = BTRFS_EXTENT_ITEM_KEY
1926 * ins->offset == number of blocks
1927 * Any available blocks before search_start are skipped.
1929 static int noinline find_free_extent(struct btrfs_trans_handle *trans,
1930 struct btrfs_root *orig_root,
1931 u64 num_bytes, u64 empty_size,
1932 u64 search_start, u64 search_end,
1933 u64 hint_byte, struct btrfs_key *ins,
1934 u64 exclude_start, u64 exclude_nr,
1938 u64 orig_search_start;
1939 struct btrfs_root * root = orig_root->fs_info->extent_root;
1940 struct btrfs_fs_info *info = root->fs_info;
1941 u64 total_needed = num_bytes;
1942 u64 *last_ptr = NULL;
1943 struct btrfs_block_group_cache *block_group;
1946 int chunk_alloc_done = 0;
1947 int empty_cluster = 2 * 1024 * 1024;
1948 int allowed_chunk_alloc = 0;
1950 WARN_ON(num_bytes < root->sectorsize);
1951 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
1953 if (orig_root->ref_cows || empty_size)
1954 allowed_chunk_alloc = 1;
1956 if (data & BTRFS_BLOCK_GROUP_METADATA) {
1957 last_ptr = &root->fs_info->last_alloc;
1958 empty_cluster = 256 * 1024;
1961 if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
1962 last_ptr = &root->fs_info->last_data_alloc;
1964 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
1965 last_ptr = &root->fs_info->last_log_alloc;
1966 if (!last_ptr == 0 && root->fs_info->last_alloc) {
1967 *last_ptr = root->fs_info->last_alloc + empty_cluster;
1973 hint_byte = *last_ptr;
1975 empty_size += empty_cluster;
1979 search_start = max(search_start, first_logical_byte(root, 0));
1980 orig_search_start = search_start;
1982 if (search_end == (u64)-1)
1983 search_end = btrfs_super_total_bytes(&info->super_copy);
1986 block_group = btrfs_lookup_first_block_group(info, hint_byte);
1988 hint_byte = search_start;
1989 block_group = btrfs_find_block_group(root, block_group,
1990 hint_byte, data, 1);
1991 if (last_ptr && *last_ptr == 0 && block_group)
1992 hint_byte = block_group->key.objectid;
1994 block_group = btrfs_find_block_group(root,
1996 search_start, data, 1);
1998 search_start = max(search_start, hint_byte);
2000 total_needed += empty_size;
2004 block_group = btrfs_lookup_first_block_group(info,
2007 block_group = btrfs_lookup_first_block_group(info,
2010 if (full_scan && !chunk_alloc_done) {
2011 if (allowed_chunk_alloc) {
2012 do_chunk_alloc(trans, root,
2013 num_bytes + 2 * 1024 * 1024, data, 1);
2014 allowed_chunk_alloc = 0;
2015 } else if (block_group && block_group_bits(block_group, data)) {
2016 block_group->space_info->force_alloc = 1;
2018 chunk_alloc_done = 1;
2020 ret = find_search_start(root, &block_group, &search_start,
2021 total_needed, data);
2022 if (ret == -ENOSPC && last_ptr && *last_ptr) {
2024 block_group = btrfs_lookup_first_block_group(info,
2026 search_start = orig_search_start;
2027 ret = find_search_start(root, &block_group, &search_start,
2028 total_needed, data);
2035 if (last_ptr && *last_ptr && search_start != *last_ptr) {
2038 empty_size += empty_cluster;
2039 total_needed += empty_size;
2041 block_group = btrfs_lookup_first_block_group(info,
2043 search_start = orig_search_start;
2044 ret = find_search_start(root, &block_group,
2045 &search_start, total_needed, data);
2052 search_start = stripe_align(root, search_start);
2053 ins->objectid = search_start;
2054 ins->offset = num_bytes;
2056 if (ins->objectid + num_bytes >= search_end)
2059 if (ins->objectid + num_bytes >
2060 block_group->key.objectid + block_group->key.offset) {
2061 search_start = block_group->key.objectid +
2062 block_group->key.offset;
2066 if (test_range_bit(&info->extent_ins, ins->objectid,
2067 ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
2068 search_start = ins->objectid + num_bytes;
2072 if (test_range_bit(&info->pinned_extents, ins->objectid,
2073 ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
2074 search_start = ins->objectid + num_bytes;
2078 if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
2079 ins->objectid < exclude_start + exclude_nr)) {
2080 search_start = exclude_start + exclude_nr;
2084 if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
2085 block_group = btrfs_lookup_block_group(info, ins->objectid);
2087 trans->block_group = block_group;
2089 ins->offset = num_bytes;
2091 *last_ptr = ins->objectid + ins->offset;
2093 btrfs_super_total_bytes(&root->fs_info->super_copy)) {
2100 if (search_start + num_bytes >= search_end) {
2102 search_start = orig_search_start;
2109 total_needed -= empty_size;
2114 block_group = btrfs_lookup_first_block_group(info, search_start);
2116 block_group = btrfs_find_block_group(root, block_group,
2117 search_start, data, 0);
2124 static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
2125 struct btrfs_root *root,
2126 u64 num_bytes, u64 min_alloc_size,
2127 u64 empty_size, u64 hint_byte,
2128 u64 search_end, struct btrfs_key *ins,
2132 u64 search_start = 0;
2134 struct btrfs_fs_info *info = root->fs_info;
2137 alloc_profile = info->avail_data_alloc_bits &
2138 info->data_alloc_profile;
2139 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
2140 } else if (root == root->fs_info->chunk_root) {
2141 alloc_profile = info->avail_system_alloc_bits &
2142 info->system_alloc_profile;
2143 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
2145 alloc_profile = info->avail_metadata_alloc_bits &
2146 info->metadata_alloc_profile;
2147 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
2150 data = reduce_alloc_profile(root, data);
2152 * the only place that sets empty_size is btrfs_realloc_node, which
2153 * is not called recursively on allocations
2155 if (empty_size || root->ref_cows) {
2156 if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
2157 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2159 BTRFS_BLOCK_GROUP_METADATA |
2160 (info->metadata_alloc_profile &
2161 info->avail_metadata_alloc_bits), 0);
2164 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2165 num_bytes + 2 * 1024 * 1024, data, 0);
2169 WARN_ON(num_bytes < root->sectorsize);
2170 ret = find_free_extent(trans, root, num_bytes, empty_size,
2171 search_start, search_end, hint_byte, ins,
2172 trans->alloc_exclude_start,
2173 trans->alloc_exclude_nr, data);
2175 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
2176 num_bytes = num_bytes >> 1;
2177 num_bytes = max(num_bytes, min_alloc_size);
2178 do_chunk_alloc(trans, root->fs_info->extent_root,
2179 num_bytes, data, 1);
2183 printk("allocation failed flags %Lu\n", data);
2186 clear_extent_dirty(&root->fs_info->free_space_cache,
2187 ins->objectid, ins->objectid + ins->offset - 1,
2192 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
2194 maybe_lock_mutex(root);
2195 set_extent_dirty(&root->fs_info->free_space_cache,
2196 start, start + len - 1, GFP_NOFS);
2197 maybe_unlock_mutex(root);
2201 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
2202 struct btrfs_root *root,
2203 u64 num_bytes, u64 min_alloc_size,
2204 u64 empty_size, u64 hint_byte,
2205 u64 search_end, struct btrfs_key *ins,
2209 maybe_lock_mutex(root);
2210 ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size,
2211 empty_size, hint_byte, search_end, ins,
2213 maybe_unlock_mutex(root);
2217 static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
2218 struct btrfs_root *root,
2219 u64 root_objectid, u64 ref_generation,
2220 u64 owner, u64 owner_offset,
2221 struct btrfs_key *ins)
2227 u64 num_bytes = ins->offset;
2229 struct btrfs_fs_info *info = root->fs_info;
2230 struct btrfs_root *extent_root = info->extent_root;
2231 struct btrfs_extent_item *extent_item;
2232 struct btrfs_extent_ref *ref;
2233 struct btrfs_path *path;
2234 struct btrfs_key keys[2];
2236 /* block accounting for super block */
2237 spin_lock_irq(&info->delalloc_lock);
2238 super_used = btrfs_super_bytes_used(&info->super_copy);
2239 btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes);
2240 spin_unlock_irq(&info->delalloc_lock);
2242 /* block accounting for root item */
2243 root_used = btrfs_root_used(&root->root_item);
2244 btrfs_set_root_used(&root->root_item, root_used + num_bytes);
2246 if (root == extent_root) {
2247 set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
2248 ins->objectid + ins->offset - 1,
2249 EXTENT_LOCKED, GFP_NOFS);
2253 memcpy(&keys[0], ins, sizeof(*ins));
2254 keys[1].offset = hash_extent_ref(root_objectid, ref_generation,
2255 owner, owner_offset);
2256 keys[1].objectid = ins->objectid;
2257 keys[1].type = BTRFS_EXTENT_REF_KEY;
2258 sizes[0] = sizeof(*extent_item);
2259 sizes[1] = sizeof(*ref);
2261 path = btrfs_alloc_path();
2264 ret = btrfs_insert_empty_items(trans, extent_root, path, keys,
2268 extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2269 struct btrfs_extent_item);
2270 btrfs_set_extent_refs(path->nodes[0], extent_item, 1);
2271 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
2272 struct btrfs_extent_ref);
2274 btrfs_set_ref_root(path->nodes[0], ref, root_objectid);
2275 btrfs_set_ref_generation(path->nodes[0], ref, ref_generation);
2276 btrfs_set_ref_objectid(path->nodes[0], ref, owner);
2277 btrfs_set_ref_offset(path->nodes[0], ref, owner_offset);
2279 btrfs_mark_buffer_dirty(path->nodes[0]);
2281 trans->alloc_exclude_start = 0;
2282 trans->alloc_exclude_nr = 0;
2283 btrfs_free_path(path);
2284 finish_current_insert(trans, extent_root);
2285 pending_ret = del_pending_extents(trans, extent_root);
2295 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0);
2297 printk("update block group failed for %Lu %Lu\n",
2298 ins->objectid, ins->offset);
2305 int btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
2306 struct btrfs_root *root,
2307 u64 root_objectid, u64 ref_generation,
2308 u64 owner, u64 owner_offset,
2309 struct btrfs_key *ins)
2312 maybe_lock_mutex(root);
2313 ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid,
2314 ref_generation, owner,
2316 maybe_unlock_mutex(root);
2321 * this is used by the tree logging recovery code. It records that
2322 * an extent has been allocated and makes sure to clear the free
2323 * space cache bits as well
2325 int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans,
2326 struct btrfs_root *root,
2327 u64 root_objectid, u64 ref_generation,
2328 u64 owner, u64 owner_offset,
2329 struct btrfs_key *ins)
2332 struct btrfs_block_group_cache *block_group;
2334 maybe_lock_mutex(root);
2335 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
2336 cache_block_group(root, block_group);
2338 clear_extent_dirty(&root->fs_info->free_space_cache,
2339 ins->objectid, ins->objectid + ins->offset - 1,
2341 ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid,
2342 ref_generation, owner,
2344 maybe_unlock_mutex(root);
2349 * finds a free extent and does all the dirty work required for allocation
2350 * returns the key for the extent through ins, and a tree buffer for
2351 * the first block of the extent through buf.
2353 * returns 0 if everything worked, non-zero otherwise.
2355 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
2356 struct btrfs_root *root,
2357 u64 num_bytes, u64 min_alloc_size,
2358 u64 root_objectid, u64 ref_generation,
2359 u64 owner, u64 owner_offset,
2360 u64 empty_size, u64 hint_byte,
2361 u64 search_end, struct btrfs_key *ins, u64 data)
2365 maybe_lock_mutex(root);
2367 ret = __btrfs_reserve_extent(trans, root, num_bytes,
2368 min_alloc_size, empty_size, hint_byte,
2369 search_end, ins, data);
2371 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
2372 ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid,
2373 ref_generation, owner,
2378 maybe_unlock_mutex(root);
2382 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
2383 struct btrfs_root *root,
2384 u64 bytenr, u32 blocksize)
2386 struct extent_buffer *buf;
2388 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
2390 return ERR_PTR(-ENOMEM);
2391 btrfs_set_header_generation(buf, trans->transid);
2392 btrfs_tree_lock(buf);
2393 clean_tree_block(trans, root, buf);
2394 btrfs_set_buffer_uptodate(buf);
2395 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
2396 buf->start + buf->len - 1, GFP_NOFS);
2397 trans->blocks_used++;
2402 * helper function to allocate a block for a given tree
2403 * returns the tree buffer or NULL.
2405 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
2406 struct btrfs_root *root,
2415 struct btrfs_key ins;
2417 struct extent_buffer *buf;
2419 ret = btrfs_alloc_extent(trans, root, blocksize, blocksize,
2420 root_objectid, ref_generation,
2421 level, first_objectid, empty_size, hint,
2425 return ERR_PTR(ret);
2428 buf = btrfs_init_new_buffer(trans, root, ins.objectid, blocksize);
2432 int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
2433 struct btrfs_root *root, struct extent_buffer *leaf)
2436 u64 leaf_generation;
2437 struct btrfs_key key;
2438 struct btrfs_file_extent_item *fi;
2443 BUG_ON(!btrfs_is_leaf(leaf));
2444 nritems = btrfs_header_nritems(leaf);
2445 leaf_owner = btrfs_header_owner(leaf);
2446 leaf_generation = btrfs_header_generation(leaf);
2448 for (i = 0; i < nritems; i++) {
2452 btrfs_item_key_to_cpu(leaf, &key, i);
2453 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2455 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
2456 if (btrfs_file_extent_type(leaf, fi) ==
2457 BTRFS_FILE_EXTENT_INLINE)
2460 * FIXME make sure to insert a trans record that
2461 * repeats the snapshot del on crash
2463 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
2464 if (disk_bytenr == 0)
2467 mutex_lock(&root->fs_info->alloc_mutex);
2468 ret = __btrfs_free_extent(trans, root, disk_bytenr,
2469 btrfs_file_extent_disk_num_bytes(leaf, fi),
2470 leaf_owner, leaf_generation,
2471 key.objectid, key.offset, 0);
2472 mutex_unlock(&root->fs_info->alloc_mutex);
2474 atomic_inc(&root->fs_info->throttle_gen);
2475 wake_up(&root->fs_info->transaction_throttle);
2483 static int noinline cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
2484 struct btrfs_root *root,
2485 struct btrfs_leaf_ref *ref)
2489 struct btrfs_extent_info *info = ref->extents;
2491 for (i = 0; i < ref->nritems; i++) {
2492 mutex_lock(&root->fs_info->alloc_mutex);
2493 ret = __btrfs_free_extent(trans, root,
2494 info->bytenr, info->num_bytes,
2495 ref->owner, ref->generation,
2496 info->objectid, info->offset, 0);
2497 mutex_unlock(&root->fs_info->alloc_mutex);
2499 atomic_inc(&root->fs_info->throttle_gen);
2500 wake_up(&root->fs_info->transaction_throttle);
2510 int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len,
2515 ret = lookup_extent_ref(NULL, root, start, len, refs);
2518 #if 0 // some debugging code in case we see problems here
2519 /* if the refs count is one, it won't get increased again. But
2520 * if the ref count is > 1, someone may be decreasing it at
2521 * the same time we are.
2524 struct extent_buffer *eb = NULL;
2525 eb = btrfs_find_create_tree_block(root, start, len);
2527 btrfs_tree_lock(eb);
2529 mutex_lock(&root->fs_info->alloc_mutex);
2530 ret = lookup_extent_ref(NULL, root, start, len, refs);
2532 mutex_unlock(&root->fs_info->alloc_mutex);
2535 btrfs_tree_unlock(eb);
2536 free_extent_buffer(eb);
2539 printk("block %llu went down to one during drop_snap\n",
2540 (unsigned long long)start);
2551 * helper function for drop_snapshot, this walks down the tree dropping ref
2552 * counts as it goes.
2554 static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
2555 struct btrfs_root *root,
2556 struct btrfs_path *path, int *level)
2562 struct extent_buffer *next;
2563 struct extent_buffer *cur;
2564 struct extent_buffer *parent;
2565 struct btrfs_leaf_ref *ref;
2570 WARN_ON(*level < 0);
2571 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2572 ret = drop_snap_lookup_refcount(root, path->nodes[*level]->start,
2573 path->nodes[*level]->len, &refs);
2579 * walk down to the last node level and free all the leaves
2581 while(*level >= 0) {
2582 WARN_ON(*level < 0);
2583 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2584 cur = path->nodes[*level];
2586 if (btrfs_header_level(cur) != *level)
2589 if (path->slots[*level] >=
2590 btrfs_header_nritems(cur))
2593 ret = btrfs_drop_leaf_ref(trans, root, cur);
2597 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
2598 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
2599 blocksize = btrfs_level_size(root, *level - 1);
2601 ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs);
2604 parent = path->nodes[*level];
2605 root_owner = btrfs_header_owner(parent);
2606 root_gen = btrfs_header_generation(parent);
2607 path->slots[*level]++;
2609 mutex_lock(&root->fs_info->alloc_mutex);
2610 ret = __btrfs_free_extent(trans, root, bytenr,
2611 blocksize, root_owner,
2614 mutex_unlock(&root->fs_info->alloc_mutex);
2616 atomic_inc(&root->fs_info->throttle_gen);
2617 wake_up(&root->fs_info->transaction_throttle);
2623 * at this point, we have a single ref, and since the
2624 * only place referencing this extent is a dead root
2625 * the reference count should never go higher.
2626 * So, we don't need to check it again
2629 struct btrfs_key key;
2630 btrfs_node_key_to_cpu(cur, &key, path->slots[*level]);
2631 ref = btrfs_lookup_leaf_ref(root, bytenr);
2633 ret = cache_drop_leaf_ref(trans, root, ref);
2635 btrfs_remove_leaf_ref(root, ref);
2636 btrfs_free_leaf_ref(root, ref);
2640 if (printk_ratelimit())
2641 printk("leaf ref miss for bytenr %llu\n",
2642 (unsigned long long)bytenr);
2644 next = btrfs_find_tree_block(root, bytenr, blocksize);
2645 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
2646 free_extent_buffer(next);
2648 next = read_tree_block(root, bytenr, blocksize,
2653 * this is a debugging check and can go away
2654 * the ref should never go all the way down to 1
2657 ret = lookup_extent_ref(NULL, root, bytenr, blocksize,
2663 WARN_ON(*level <= 0);
2664 if (path->nodes[*level-1])
2665 free_extent_buffer(path->nodes[*level-1]);
2666 path->nodes[*level-1] = next;
2667 *level = btrfs_header_level(next);
2668 path->slots[*level] = 0;
2672 WARN_ON(*level < 0);
2673 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2675 if (path->nodes[*level] == root->node) {
2676 parent = path->nodes[*level];
2677 bytenr = path->nodes[*level]->start;
2679 parent = path->nodes[*level + 1];
2680 bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]);
2683 blocksize = btrfs_level_size(root, *level);
2684 root_owner = btrfs_header_owner(parent);
2685 root_gen = btrfs_header_generation(parent);
2687 mutex_lock(&root->fs_info->alloc_mutex);
2688 ret = __btrfs_free_extent(trans, root, bytenr, blocksize,
2689 root_owner, root_gen, 0, 0, 1);
2690 free_extent_buffer(path->nodes[*level]);
2691 path->nodes[*level] = NULL;
2694 mutex_unlock(&root->fs_info->alloc_mutex);
2701 * helper for dropping snapshots. This walks back up the tree in the path
2702 * to find the first node higher up where we haven't yet gone through
2705 static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
2706 struct btrfs_root *root,
2707 struct btrfs_path *path, int *level)
2711 struct btrfs_root_item *root_item = &root->root_item;
2716 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
2717 slot = path->slots[i];
2718 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
2719 struct extent_buffer *node;
2720 struct btrfs_disk_key disk_key;
2721 node = path->nodes[i];
2724 WARN_ON(*level == 0);
2725 btrfs_node_key(node, &disk_key, path->slots[i]);
2726 memcpy(&root_item->drop_progress,
2727 &disk_key, sizeof(disk_key));
2728 root_item->drop_level = i;
2731 if (path->nodes[*level] == root->node) {
2732 root_owner = root->root_key.objectid;
2734 btrfs_header_generation(path->nodes[*level]);
2736 struct extent_buffer *node;
2737 node = path->nodes[*level + 1];
2738 root_owner = btrfs_header_owner(node);
2739 root_gen = btrfs_header_generation(node);
2741 ret = btrfs_free_extent(trans, root,
2742 path->nodes[*level]->start,
2743 path->nodes[*level]->len,
2744 root_owner, root_gen, 0, 0, 1);
2746 free_extent_buffer(path->nodes[*level]);
2747 path->nodes[*level] = NULL;
2755 * drop the reference count on the tree rooted at 'snap'. This traverses
2756 * the tree freeing any blocks that have a ref count of zero after being
2759 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
2765 struct btrfs_path *path;
2768 struct btrfs_root_item *root_item = &root->root_item;
2770 WARN_ON(!mutex_is_locked(&root->fs_info->drop_mutex));
2771 path = btrfs_alloc_path();
2774 level = btrfs_header_level(root->node);
2776 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
2777 path->nodes[level] = root->node;
2778 extent_buffer_get(root->node);
2779 path->slots[level] = 0;
2781 struct btrfs_key key;
2782 struct btrfs_disk_key found_key;
2783 struct extent_buffer *node;
2785 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
2786 level = root_item->drop_level;
2787 path->lowest_level = level;
2788 wret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2793 node = path->nodes[level];
2794 btrfs_node_key(node, &found_key, path->slots[level]);
2795 WARN_ON(memcmp(&found_key, &root_item->drop_progress,
2796 sizeof(found_key)));
2798 * unlock our path, this is safe because only this
2799 * function is allowed to delete this snapshot
2801 for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
2802 if (path->nodes[i] && path->locks[i]) {
2804 btrfs_tree_unlock(path->nodes[i]);
2809 wret = walk_down_tree(trans, root, path, &level);
2815 wret = walk_up_tree(trans, root, path, &level);
2820 if (trans->transaction->in_commit) {
2824 atomic_inc(&root->fs_info->throttle_gen);
2825 wake_up(&root->fs_info->transaction_throttle);
2827 for (i = 0; i <= orig_level; i++) {
2828 if (path->nodes[i]) {
2829 free_extent_buffer(path->nodes[i]);
2830 path->nodes[i] = NULL;
2834 btrfs_free_path(path);
2838 int btrfs_free_block_groups(struct btrfs_fs_info *info)
2845 mutex_lock(&info->alloc_mutex);
2847 ret = find_first_extent_bit(&info->block_group_cache, 0,
2848 &start, &end, (unsigned int)-1);
2851 ret = get_state_private(&info->block_group_cache, start, &ptr);
2853 kfree((void *)(unsigned long)ptr);
2854 clear_extent_bits(&info->block_group_cache, start,
2855 end, (unsigned int)-1, GFP_NOFS);
2858 ret = find_first_extent_bit(&info->free_space_cache, 0,
2859 &start, &end, EXTENT_DIRTY);
2862 clear_extent_dirty(&info->free_space_cache, start,
2865 mutex_unlock(&info->alloc_mutex);
2869 static unsigned long calc_ra(unsigned long start, unsigned long last,
2872 return min(last, start + nr - 1);
2875 static int noinline relocate_inode_pages(struct inode *inode, u64 start,
2880 unsigned long last_index;
2883 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2884 struct file_ra_state *ra;
2885 unsigned long total_read = 0;
2886 unsigned long ra_pages;
2887 struct btrfs_ordered_extent *ordered;
2888 struct btrfs_trans_handle *trans;
2890 ra = kzalloc(sizeof(*ra), GFP_NOFS);
2892 mutex_lock(&inode->i_mutex);
2893 i = start >> PAGE_CACHE_SHIFT;
2894 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
2896 ra_pages = BTRFS_I(inode)->root->fs_info->bdi.ra_pages;
2898 file_ra_state_init(ra, inode->i_mapping);
2900 for (; i <= last_index; i++) {
2901 if (total_read % ra_pages == 0) {
2902 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
2903 calc_ra(i, last_index, ra_pages));
2907 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
2908 goto truncate_racing;
2909 page = grab_cache_page(inode->i_mapping, i);
2913 if (!PageUptodate(page)) {
2914 btrfs_readpage(NULL, page);
2916 if (!PageUptodate(page)) {
2918 page_cache_release(page);
2922 wait_on_page_writeback(page);
2924 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2925 page_end = page_start + PAGE_CACHE_SIZE - 1;
2926 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
2928 ordered = btrfs_lookup_ordered_extent(inode, page_start);
2930 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2932 page_cache_release(page);
2933 btrfs_start_ordered_extent(inode, ordered, 1);
2934 btrfs_put_ordered_extent(ordered);
2937 set_page_extent_mapped(page);
2940 * make sure page_mkwrite is called for this page if userland
2941 * wants to change it from mmap
2943 clear_page_dirty_for_io(page);
2945 btrfs_set_extent_delalloc(inode, page_start, page_end);
2946 set_page_dirty(page);
2948 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2950 page_cache_release(page);
2954 /* we have to start the IO in order to get the ordered extents
2955 * instantiated. This allows the relocation to code to wait
2956 * for all the ordered extents to hit the disk.
2958 * Otherwise, it would constantly loop over the same extents
2959 * because the old ones don't get deleted until the IO is
2962 btrfs_fdatawrite_range(inode->i_mapping, start, start + len - 1,
2965 trans = btrfs_start_transaction(BTRFS_I(inode)->root, 1);
2967 btrfs_end_transaction(trans, BTRFS_I(inode)->root);
2968 mark_inode_dirty(inode);
2970 mutex_unlock(&inode->i_mutex);
2974 vmtruncate(inode, inode->i_size);
2975 balance_dirty_pages_ratelimited_nr(inode->i_mapping,
2981 * The back references tell us which tree holds a ref on a block,
2982 * but it is possible for the tree root field in the reference to
2983 * reflect the original root before a snapshot was made. In this
2984 * case we should search through all the children of a given root
2985 * to find potential holders of references on a block.
2987 * Instead, we do something a little less fancy and just search
2988 * all the roots for a given key/block combination.
2990 static int find_root_for_ref(struct btrfs_root *root,
2991 struct btrfs_path *path,
2992 struct btrfs_key *key0,
2995 struct btrfs_root **found_root,
2998 struct btrfs_key root_location;
2999 struct btrfs_root *cur_root = *found_root;
3000 struct btrfs_file_extent_item *file_extent;
3001 u64 root_search_start = BTRFS_FS_TREE_OBJECTID;
3005 root_location.offset = (u64)-1;
3006 root_location.type = BTRFS_ROOT_ITEM_KEY;
3007 path->lowest_level = level;
3010 ret = btrfs_search_slot(NULL, cur_root, key0, path, 0, 0);
3012 if (ret == 0 && file_key) {
3013 struct extent_buffer *leaf = path->nodes[0];
3014 file_extent = btrfs_item_ptr(leaf, path->slots[0],
3015 struct btrfs_file_extent_item);
3016 if (btrfs_file_extent_type(leaf, file_extent) ==
3017 BTRFS_FILE_EXTENT_REG) {
3019 btrfs_file_extent_disk_bytenr(leaf,
3022 } else if (!file_key) {
3023 if (path->nodes[level])
3024 found_bytenr = path->nodes[level]->start;
3027 btrfs_release_path(cur_root, path);
3029 if (found_bytenr == bytenr) {
3030 *found_root = cur_root;
3034 ret = btrfs_search_root(root->fs_info->tree_root,
3035 root_search_start, &root_search_start);
3039 root_location.objectid = root_search_start;
3040 cur_root = btrfs_read_fs_root_no_name(root->fs_info,
3048 path->lowest_level = 0;
3053 * note, this releases the path
3055 static int noinline relocate_one_reference(struct btrfs_root *extent_root,
3056 struct btrfs_path *path,
3057 struct btrfs_key *extent_key,
3058 u64 *last_file_objectid,
3059 u64 *last_file_offset,
3060 u64 *last_file_root,
3063 struct inode *inode;
3064 struct btrfs_root *found_root;
3065 struct btrfs_key root_location;
3066 struct btrfs_key found_key;
3067 struct btrfs_extent_ref *ref;
3075 WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
3077 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
3078 struct btrfs_extent_ref);
3079 ref_root = btrfs_ref_root(path->nodes[0], ref);
3080 ref_gen = btrfs_ref_generation(path->nodes[0], ref);
3081 ref_objectid = btrfs_ref_objectid(path->nodes[0], ref);
3082 ref_offset = btrfs_ref_offset(path->nodes[0], ref);
3083 btrfs_release_path(extent_root, path);
3085 root_location.objectid = ref_root;
3087 root_location.offset = 0;
3089 root_location.offset = (u64)-1;
3090 root_location.type = BTRFS_ROOT_ITEM_KEY;
3092 found_root = btrfs_read_fs_root_no_name(extent_root->fs_info,
3094 BUG_ON(!found_root);
3095 mutex_unlock(&extent_root->fs_info->alloc_mutex);
3097 if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
3098 found_key.objectid = ref_objectid;
3099 found_key.type = BTRFS_EXTENT_DATA_KEY;
3100 found_key.offset = ref_offset;
3103 if (last_extent == extent_key->objectid &&
3104 *last_file_objectid == ref_objectid &&
3105 *last_file_offset == ref_offset &&
3106 *last_file_root == ref_root)
3109 ret = find_root_for_ref(extent_root, path, &found_key,
3110 level, 1, &found_root,
3111 extent_key->objectid);
3116 if (last_extent == extent_key->objectid &&
3117 *last_file_objectid == ref_objectid &&
3118 *last_file_offset == ref_offset &&
3119 *last_file_root == ref_root)
3122 inode = btrfs_iget_locked(extent_root->fs_info->sb,
3123 ref_objectid, found_root);
3124 if (inode->i_state & I_NEW) {
3125 /* the inode and parent dir are two different roots */
3126 BTRFS_I(inode)->root = found_root;
3127 BTRFS_I(inode)->location.objectid = ref_objectid;
3128 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
3129 BTRFS_I(inode)->location.offset = 0;
3130 btrfs_read_locked_inode(inode);
3131 unlock_new_inode(inode);
3134 /* this can happen if the reference is not against
3135 * the latest version of the tree root
3137 if (is_bad_inode(inode))
3140 *last_file_objectid = inode->i_ino;
3141 *last_file_root = found_root->root_key.objectid;
3142 *last_file_offset = ref_offset;
3144 relocate_inode_pages(inode, ref_offset, extent_key->offset);
3147 struct btrfs_trans_handle *trans;
3148 struct extent_buffer *eb;
3151 eb = read_tree_block(found_root, extent_key->objectid,
3152 extent_key->offset, 0);
3153 btrfs_tree_lock(eb);
3154 level = btrfs_header_level(eb);
3157 btrfs_item_key_to_cpu(eb, &found_key, 0);
3159 btrfs_node_key_to_cpu(eb, &found_key, 0);
3161 btrfs_tree_unlock(eb);
3162 free_extent_buffer(eb);
3164 ret = find_root_for_ref(extent_root, path, &found_key,
3165 level, 0, &found_root,
3166 extent_key->objectid);
3172 * right here almost anything could happen to our key,
3173 * but that's ok. The cow below will either relocate it
3174 * or someone else will have relocated it. Either way,
3175 * it is in a different spot than it was before and
3179 trans = btrfs_start_transaction(found_root, 1);
3181 if (found_root == extent_root->fs_info->extent_root ||
3182 found_root == extent_root->fs_info->chunk_root ||
3183 found_root == extent_root->fs_info->dev_root) {
3185 mutex_lock(&extent_root->fs_info->alloc_mutex);
3188 path->lowest_level = level;
3190 ret = btrfs_search_slot(trans, found_root, &found_key, path,
3192 path->lowest_level = 0;
3193 btrfs_release_path(found_root, path);
3195 if (found_root == found_root->fs_info->extent_root)
3196 btrfs_extent_post_op(trans, found_root);
3198 mutex_unlock(&extent_root->fs_info->alloc_mutex);
3200 btrfs_end_transaction(trans, found_root);
3204 mutex_lock(&extent_root->fs_info->alloc_mutex);
3208 static int noinline del_extent_zero(struct btrfs_root *extent_root,
3209 struct btrfs_path *path,
3210 struct btrfs_key *extent_key)
3213 struct btrfs_trans_handle *trans;
3215 trans = btrfs_start_transaction(extent_root, 1);
3216 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
3223 ret = btrfs_del_item(trans, extent_root, path);
3225 btrfs_end_transaction(trans, extent_root);
3229 static int noinline relocate_one_extent(struct btrfs_root *extent_root,
3230 struct btrfs_path *path,
3231 struct btrfs_key *extent_key)
3233 struct btrfs_key key;
3234 struct btrfs_key found_key;
3235 struct extent_buffer *leaf;
3236 u64 last_file_objectid = 0;
3237 u64 last_file_root = 0;
3238 u64 last_file_offset = (u64)-1;
3239 u64 last_extent = 0;
3244 if (extent_key->objectid == 0) {
3245 ret = del_extent_zero(extent_root, path, extent_key);
3248 key.objectid = extent_key->objectid;
3249 key.type = BTRFS_EXTENT_REF_KEY;
3253 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
3259 leaf = path->nodes[0];
3260 nritems = btrfs_header_nritems(leaf);
3261 if (path->slots[0] == nritems) {
3262 ret = btrfs_next_leaf(extent_root, path);
3269 leaf = path->nodes[0];
3272 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3273 if (found_key.objectid != extent_key->objectid) {
3277 if (found_key.type != BTRFS_EXTENT_REF_KEY) {
3281 key.offset = found_key.offset + 1;
3282 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
3284 ret = relocate_one_reference(extent_root, path, extent_key,
3285 &last_file_objectid,
3287 &last_file_root, last_extent);
3290 last_extent = extent_key->objectid;
3294 btrfs_release_path(extent_root, path);
3298 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
3301 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
3302 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
3304 num_devices = root->fs_info->fs_devices->num_devices;
3305 if (num_devices == 1) {
3306 stripped |= BTRFS_BLOCK_GROUP_DUP;
3307 stripped = flags & ~stripped;
3309 /* turn raid0 into single device chunks */
3310 if (flags & BTRFS_BLOCK_GROUP_RAID0)
3313 /* turn mirroring into duplication */
3314 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3315 BTRFS_BLOCK_GROUP_RAID10))
3316 return stripped | BTRFS_BLOCK_GROUP_DUP;
3319 /* they already had raid on here, just return */
3320 if (flags & stripped)
3323 stripped |= BTRFS_BLOCK_GROUP_DUP;
3324 stripped = flags & ~stripped;
3326 /* switch duplicated blocks with raid1 */
3327 if (flags & BTRFS_BLOCK_GROUP_DUP)
3328 return stripped | BTRFS_BLOCK_GROUP_RAID1;
3330 /* turn single device chunks into raid0 */
3331 return stripped | BTRFS_BLOCK_GROUP_RAID0;
3336 int __alloc_chunk_for_shrink(struct btrfs_root *root,
3337 struct btrfs_block_group_cache *shrink_block_group,
3340 struct btrfs_trans_handle *trans;
3341 u64 new_alloc_flags;
3344 spin_lock(&shrink_block_group->lock);
3345 if (btrfs_block_group_used(&shrink_block_group->item) > 0) {
3346 spin_unlock(&shrink_block_group->lock);
3347 mutex_unlock(&root->fs_info->alloc_mutex);
3349 trans = btrfs_start_transaction(root, 1);
3350 mutex_lock(&root->fs_info->alloc_mutex);
3351 spin_lock(&shrink_block_group->lock);
3353 new_alloc_flags = update_block_group_flags(root,
3354 shrink_block_group->flags);
3355 if (new_alloc_flags != shrink_block_group->flags) {
3357 btrfs_block_group_used(&shrink_block_group->item);
3359 calc = shrink_block_group->key.offset;
3361 spin_unlock(&shrink_block_group->lock);
3363 do_chunk_alloc(trans, root->fs_info->extent_root,
3364 calc + 2 * 1024 * 1024, new_alloc_flags, force);
3366 mutex_unlock(&root->fs_info->alloc_mutex);
3367 btrfs_end_transaction(trans, root);
3368 mutex_lock(&root->fs_info->alloc_mutex);
3370 spin_unlock(&shrink_block_group->lock);
3374 int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start)
3376 struct btrfs_trans_handle *trans;
3377 struct btrfs_root *tree_root = root->fs_info->tree_root;
3378 struct btrfs_path *path;
3381 u64 shrink_last_byte;
3382 struct btrfs_block_group_cache *shrink_block_group;
3383 struct btrfs_fs_info *info = root->fs_info;
3384 struct btrfs_key key;
3385 struct btrfs_key found_key;
3386 struct extent_buffer *leaf;
3391 mutex_lock(&root->fs_info->alloc_mutex);
3392 shrink_block_group = btrfs_lookup_block_group(root->fs_info,
3394 BUG_ON(!shrink_block_group);
3396 shrink_last_byte = shrink_block_group->key.objectid +
3397 shrink_block_group->key.offset;
3399 shrink_block_group->space_info->total_bytes -=
3400 shrink_block_group->key.offset;
3401 path = btrfs_alloc_path();
3402 root = root->fs_info->extent_root;
3405 printk("btrfs relocating block group %llu flags %llu\n",
3406 (unsigned long long)shrink_start,
3407 (unsigned long long)shrink_block_group->flags);
3409 __alloc_chunk_for_shrink(root, shrink_block_group, 1);
3413 shrink_block_group->ro = 1;
3417 key.objectid = shrink_start;
3420 cur_byte = key.objectid;
3422 mutex_unlock(&root->fs_info->alloc_mutex);
3424 btrfs_start_delalloc_inodes(root);
3425 btrfs_wait_ordered_extents(tree_root, 0);
3427 mutex_lock(&root->fs_info->alloc_mutex);
3429 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3433 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
3438 leaf = path->nodes[0];
3439 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3440 if (found_key.objectid + found_key.offset > shrink_start &&
3441 found_key.objectid < shrink_last_byte) {
3442 cur_byte = found_key.objectid;
3443 key.objectid = cur_byte;
3446 btrfs_release_path(root, path);
3449 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3454 leaf = path->nodes[0];
3455 nritems = btrfs_header_nritems(leaf);
3456 if (path->slots[0] >= nritems) {
3457 ret = btrfs_next_leaf(root, path);
3464 leaf = path->nodes[0];
3465 nritems = btrfs_header_nritems(leaf);
3468 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3470 if (found_key.objectid >= shrink_last_byte)
3473 if (progress && need_resched()) {
3474 memcpy(&key, &found_key, sizeof(key));
3476 btrfs_release_path(root, path);
3477 btrfs_search_slot(NULL, root, &key, path, 0, 0);
3483 if (btrfs_key_type(&found_key) != BTRFS_EXTENT_ITEM_KEY ||
3484 found_key.objectid + found_key.offset <= cur_byte) {
3485 memcpy(&key, &found_key, sizeof(key));
3492 cur_byte = found_key.objectid + found_key.offset;
3493 key.objectid = cur_byte;
3494 btrfs_release_path(root, path);
3495 ret = relocate_one_extent(root, path, &found_key);
3496 __alloc_chunk_for_shrink(root, shrink_block_group, 0);
3499 btrfs_release_path(root, path);
3501 if (total_found > 0) {
3502 printk("btrfs relocate found %llu last extent was %llu\n",
3503 (unsigned long long)total_found,
3504 (unsigned long long)found_key.objectid);
3505 mutex_unlock(&root->fs_info->alloc_mutex);
3506 trans = btrfs_start_transaction(tree_root, 1);
3507 btrfs_commit_transaction(trans, tree_root);
3509 btrfs_clean_old_snapshots(tree_root);
3511 btrfs_start_delalloc_inodes(root);
3512 btrfs_wait_ordered_extents(tree_root, 0);
3514 trans = btrfs_start_transaction(tree_root, 1);
3515 btrfs_commit_transaction(trans, tree_root);
3516 mutex_lock(&root->fs_info->alloc_mutex);
3521 * we've freed all the extents, now remove the block
3522 * group item from the tree
3524 mutex_unlock(&root->fs_info->alloc_mutex);
3526 trans = btrfs_start_transaction(root, 1);
3528 mutex_lock(&root->fs_info->alloc_mutex);
3529 memcpy(&key, &shrink_block_group->key, sizeof(key));
3531 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3535 btrfs_end_transaction(trans, root);
3539 clear_extent_bits(&info->block_group_cache, key.objectid,
3540 key.objectid + key.offset - 1,
3541 (unsigned int)-1, GFP_NOFS);
3544 clear_extent_bits(&info->free_space_cache,
3545 key.objectid, key.objectid + key.offset - 1,
3546 (unsigned int)-1, GFP_NOFS);
3549 memset(shrink_block_group, 0, sizeof(*shrink_block_group));
3550 kfree(shrink_block_group);
3553 btrfs_del_item(trans, root, path);
3554 btrfs_release_path(root, path);
3555 mutex_unlock(&root->fs_info->alloc_mutex);
3556 btrfs_commit_transaction(trans, root);
3558 mutex_lock(&root->fs_info->alloc_mutex);
3560 /* the code to unpin extents might set a few bits in the free
3561 * space cache for this range again
3563 clear_extent_bits(&info->free_space_cache,
3564 key.objectid, key.objectid + key.offset - 1,
3565 (unsigned int)-1, GFP_NOFS);
3567 btrfs_free_path(path);
3568 mutex_unlock(&root->fs_info->alloc_mutex);
3572 int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
3573 struct btrfs_key *key)
3576 struct btrfs_key found_key;
3577 struct extent_buffer *leaf;
3580 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
3585 slot = path->slots[0];
3586 leaf = path->nodes[0];
3587 if (slot >= btrfs_header_nritems(leaf)) {
3588 ret = btrfs_next_leaf(root, path);
3595 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3597 if (found_key.objectid >= key->objectid &&
3598 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
3609 int btrfs_read_block_groups(struct btrfs_root *root)
3611 struct btrfs_path *path;
3614 struct btrfs_block_group_cache *cache;
3615 struct btrfs_fs_info *info = root->fs_info;
3616 struct btrfs_space_info *space_info;
3617 struct extent_io_tree *block_group_cache;
3618 struct btrfs_key key;
3619 struct btrfs_key found_key;
3620 struct extent_buffer *leaf;
3622 block_group_cache = &info->block_group_cache;
3623 root = info->extent_root;
3626 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3627 path = btrfs_alloc_path();
3631 mutex_lock(&root->fs_info->alloc_mutex);
3633 ret = find_first_block_group(root, path, &key);
3641 leaf = path->nodes[0];
3642 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3643 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3649 spin_lock_init(&cache->lock);
3650 read_extent_buffer(leaf, &cache->item,
3651 btrfs_item_ptr_offset(leaf, path->slots[0]),
3652 sizeof(cache->item));
3653 memcpy(&cache->key, &found_key, sizeof(found_key));
3655 key.objectid = found_key.objectid + found_key.offset;
3656 btrfs_release_path(root, path);
3657 cache->flags = btrfs_block_group_flags(&cache->item);
3659 if (cache->flags & BTRFS_BLOCK_GROUP_DATA) {
3660 bit = BLOCK_GROUP_DATA;
3661 } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
3662 bit = BLOCK_GROUP_SYSTEM;
3663 } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) {
3664 bit = BLOCK_GROUP_METADATA;
3666 set_avail_alloc_bits(info, cache->flags);
3668 ret = update_space_info(info, cache->flags, found_key.offset,
3669 btrfs_block_group_used(&cache->item),
3672 cache->space_info = space_info;
3674 /* use EXTENT_LOCKED to prevent merging */
3675 set_extent_bits(block_group_cache, found_key.objectid,
3676 found_key.objectid + found_key.offset - 1,
3677 EXTENT_LOCKED, GFP_NOFS);
3678 set_state_private(block_group_cache, found_key.objectid,
3679 (unsigned long)cache);
3680 set_extent_bits(block_group_cache, found_key.objectid,
3681 found_key.objectid + found_key.offset - 1,
3682 bit | EXTENT_LOCKED, GFP_NOFS);
3684 btrfs_super_total_bytes(&info->super_copy))
3689 btrfs_free_path(path);
3690 mutex_unlock(&root->fs_info->alloc_mutex);
3694 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
3695 struct btrfs_root *root, u64 bytes_used,
3696 u64 type, u64 chunk_objectid, u64 chunk_offset,
3701 struct btrfs_root *extent_root;
3702 struct btrfs_block_group_cache *cache;
3703 struct extent_io_tree *block_group_cache;
3705 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
3706 extent_root = root->fs_info->extent_root;
3707 block_group_cache = &root->fs_info->block_group_cache;
3709 root->fs_info->last_trans_new_blockgroup = trans->transid;
3711 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3713 cache->key.objectid = chunk_offset;
3714 cache->key.offset = size;
3715 spin_lock_init(&cache->lock);
3716 btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3718 btrfs_set_block_group_used(&cache->item, bytes_used);
3719 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
3720 cache->flags = type;
3721 btrfs_set_block_group_flags(&cache->item, type);
3723 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
3724 &cache->space_info);
3727 bit = block_group_state_bits(type);
3728 set_extent_bits(block_group_cache, chunk_offset,
3729 chunk_offset + size - 1,
3730 EXTENT_LOCKED, GFP_NOFS);
3731 set_state_private(block_group_cache, chunk_offset,
3732 (unsigned long)cache);
3733 set_extent_bits(block_group_cache, chunk_offset,
3734 chunk_offset + size - 1,
3735 bit | EXTENT_LOCKED, GFP_NOFS);
3737 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
3738 sizeof(cache->item));
3741 finish_current_insert(trans, extent_root);
3742 ret = del_pending_extents(trans, extent_root);
3744 set_avail_alloc_bits(extent_root->fs_info, type);