1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
6 #include <linux/sched.h>
7 #include <linux/sched/signal.h>
8 #include <linux/pagemap.h>
9 #include <linux/writeback.h>
10 #include <linux/blkdev.h>
11 #include <linux/sort.h>
12 #include <linux/rcupdate.h>
13 #include <linux/kthread.h>
14 #include <linux/slab.h>
15 #include <linux/ratelimit.h>
16 #include <linux/percpu_counter.h>
17 #include <linux/lockdep.h>
18 #include <linux/crc32c.h>
22 #include "print-tree.h"
26 #include "free-space-cache.h"
27 #include "free-space-tree.h"
30 #include "ref-verify.h"
31 #include "space-info.h"
32 #include "block-rsv.h"
33 #include "delalloc-space.h"
34 #include "block-group.h"
37 #undef SCRAMBLE_DELAYED_REFS
40 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
41 struct btrfs_delayed_ref_node *node, u64 parent,
42 u64 root_objectid, u64 owner_objectid,
43 u64 owner_offset, int refs_to_drop,
44 struct btrfs_delayed_extent_op *extra_op);
45 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
46 struct extent_buffer *leaf,
47 struct btrfs_extent_item *ei);
48 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
49 u64 parent, u64 root_objectid,
50 u64 flags, u64 owner, u64 offset,
51 struct btrfs_key *ins, int ref_mod);
52 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
53 struct btrfs_delayed_ref_node *node,
54 struct btrfs_delayed_extent_op *extent_op);
55 static int find_next_key(struct btrfs_path *path, int level,
56 struct btrfs_key *key);
58 static int block_group_bits(struct btrfs_block_group *cache, u64 bits)
60 return (cache->flags & bits) == bits;
63 int btrfs_add_excluded_extent(struct btrfs_fs_info *fs_info,
64 u64 start, u64 num_bytes)
66 u64 end = start + num_bytes - 1;
67 set_extent_bits(&fs_info->excluded_extents, start, end,
72 void btrfs_free_excluded_extents(struct btrfs_block_group *cache)
74 struct btrfs_fs_info *fs_info = cache->fs_info;
78 end = start + cache->length - 1;
80 clear_extent_bits(&fs_info->excluded_extents, start, end,
84 static u64 generic_ref_to_space_flags(struct btrfs_ref *ref)
86 if (ref->type == BTRFS_REF_METADATA) {
87 if (ref->tree_ref.root == BTRFS_CHUNK_TREE_OBJECTID)
88 return BTRFS_BLOCK_GROUP_SYSTEM;
90 return BTRFS_BLOCK_GROUP_METADATA;
92 return BTRFS_BLOCK_GROUP_DATA;
95 static void add_pinned_bytes(struct btrfs_fs_info *fs_info,
96 struct btrfs_ref *ref)
98 struct btrfs_space_info *space_info;
99 u64 flags = generic_ref_to_space_flags(ref);
101 space_info = btrfs_find_space_info(fs_info, flags);
103 percpu_counter_add_batch(&space_info->total_bytes_pinned, ref->len,
104 BTRFS_TOTAL_BYTES_PINNED_BATCH);
107 static void sub_pinned_bytes(struct btrfs_fs_info *fs_info,
108 struct btrfs_ref *ref)
110 struct btrfs_space_info *space_info;
111 u64 flags = generic_ref_to_space_flags(ref);
113 space_info = btrfs_find_space_info(fs_info, flags);
115 percpu_counter_add_batch(&space_info->total_bytes_pinned, -ref->len,
116 BTRFS_TOTAL_BYTES_PINNED_BATCH);
119 /* simple helper to search for an existing data extent at a given offset */
120 int btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len)
123 struct btrfs_key key;
124 struct btrfs_path *path;
126 path = btrfs_alloc_path();
130 key.objectid = start;
132 key.type = BTRFS_EXTENT_ITEM_KEY;
133 ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
134 btrfs_free_path(path);
139 * helper function to lookup reference count and flags of a tree block.
141 * the head node for delayed ref is used to store the sum of all the
142 * reference count modifications queued up in the rbtree. the head
143 * node may also store the extent flags to set. This way you can check
144 * to see what the reference count and extent flags would be if all of
145 * the delayed refs are not processed.
147 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
148 struct btrfs_fs_info *fs_info, u64 bytenr,
149 u64 offset, int metadata, u64 *refs, u64 *flags)
151 struct btrfs_delayed_ref_head *head;
152 struct btrfs_delayed_ref_root *delayed_refs;
153 struct btrfs_path *path;
154 struct btrfs_extent_item *ei;
155 struct extent_buffer *leaf;
156 struct btrfs_key key;
163 * If we don't have skinny metadata, don't bother doing anything
166 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
167 offset = fs_info->nodesize;
171 path = btrfs_alloc_path();
176 path->skip_locking = 1;
177 path->search_commit_root = 1;
181 key.objectid = bytenr;
184 key.type = BTRFS_METADATA_ITEM_KEY;
186 key.type = BTRFS_EXTENT_ITEM_KEY;
188 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0);
192 if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) {
193 if (path->slots[0]) {
195 btrfs_item_key_to_cpu(path->nodes[0], &key,
197 if (key.objectid == bytenr &&
198 key.type == BTRFS_EXTENT_ITEM_KEY &&
199 key.offset == fs_info->nodesize)
205 leaf = path->nodes[0];
206 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
207 if (item_size >= sizeof(*ei)) {
208 ei = btrfs_item_ptr(leaf, path->slots[0],
209 struct btrfs_extent_item);
210 num_refs = btrfs_extent_refs(leaf, ei);
211 extent_flags = btrfs_extent_flags(leaf, ei);
214 btrfs_print_v0_err(fs_info);
216 btrfs_abort_transaction(trans, ret);
218 btrfs_handle_fs_error(fs_info, ret, NULL);
223 BUG_ON(num_refs == 0);
233 delayed_refs = &trans->transaction->delayed_refs;
234 spin_lock(&delayed_refs->lock);
235 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
237 if (!mutex_trylock(&head->mutex)) {
238 refcount_inc(&head->refs);
239 spin_unlock(&delayed_refs->lock);
241 btrfs_release_path(path);
244 * Mutex was contended, block until it's released and try
247 mutex_lock(&head->mutex);
248 mutex_unlock(&head->mutex);
249 btrfs_put_delayed_ref_head(head);
252 spin_lock(&head->lock);
253 if (head->extent_op && head->extent_op->update_flags)
254 extent_flags |= head->extent_op->flags_to_set;
256 BUG_ON(num_refs == 0);
258 num_refs += head->ref_mod;
259 spin_unlock(&head->lock);
260 mutex_unlock(&head->mutex);
262 spin_unlock(&delayed_refs->lock);
264 WARN_ON(num_refs == 0);
268 *flags = extent_flags;
270 btrfs_free_path(path);
275 * Back reference rules. Back refs have three main goals:
277 * 1) differentiate between all holders of references to an extent so that
278 * when a reference is dropped we can make sure it was a valid reference
279 * before freeing the extent.
281 * 2) Provide enough information to quickly find the holders of an extent
282 * if we notice a given block is corrupted or bad.
284 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
285 * maintenance. This is actually the same as #2, but with a slightly
286 * different use case.
288 * There are two kinds of back refs. The implicit back refs is optimized
289 * for pointers in non-shared tree blocks. For a given pointer in a block,
290 * back refs of this kind provide information about the block's owner tree
291 * and the pointer's key. These information allow us to find the block by
292 * b-tree searching. The full back refs is for pointers in tree blocks not
293 * referenced by their owner trees. The location of tree block is recorded
294 * in the back refs. Actually the full back refs is generic, and can be
295 * used in all cases the implicit back refs is used. The major shortcoming
296 * of the full back refs is its overhead. Every time a tree block gets
297 * COWed, we have to update back refs entry for all pointers in it.
299 * For a newly allocated tree block, we use implicit back refs for
300 * pointers in it. This means most tree related operations only involve
301 * implicit back refs. For a tree block created in old transaction, the
302 * only way to drop a reference to it is COW it. So we can detect the
303 * event that tree block loses its owner tree's reference and do the
304 * back refs conversion.
306 * When a tree block is COWed through a tree, there are four cases:
308 * The reference count of the block is one and the tree is the block's
309 * owner tree. Nothing to do in this case.
311 * The reference count of the block is one and the tree is not the
312 * block's owner tree. In this case, full back refs is used for pointers
313 * in the block. Remove these full back refs, add implicit back refs for
314 * every pointers in the new block.
316 * The reference count of the block is greater than one and the tree is
317 * the block's owner tree. In this case, implicit back refs is used for
318 * pointers in the block. Add full back refs for every pointers in the
319 * block, increase lower level extents' reference counts. The original
320 * implicit back refs are entailed to the new block.
322 * The reference count of the block is greater than one and the tree is
323 * not the block's owner tree. Add implicit back refs for every pointer in
324 * the new block, increase lower level extents' reference count.
326 * Back Reference Key composing:
328 * The key objectid corresponds to the first byte in the extent,
329 * The key type is used to differentiate between types of back refs.
330 * There are different meanings of the key offset for different types
333 * File extents can be referenced by:
335 * - multiple snapshots, subvolumes, or different generations in one subvol
336 * - different files inside a single subvolume
337 * - different offsets inside a file (bookend extents in file.c)
339 * The extent ref structure for the implicit back refs has fields for:
341 * - Objectid of the subvolume root
342 * - objectid of the file holding the reference
343 * - original offset in the file
344 * - how many bookend extents
346 * The key offset for the implicit back refs is hash of the first
349 * The extent ref structure for the full back refs has field for:
351 * - number of pointers in the tree leaf
353 * The key offset for the implicit back refs is the first byte of
356 * When a file extent is allocated, The implicit back refs is used.
357 * the fields are filled in:
359 * (root_key.objectid, inode objectid, offset in file, 1)
361 * When a file extent is removed file truncation, we find the
362 * corresponding implicit back refs and check the following fields:
364 * (btrfs_header_owner(leaf), inode objectid, offset in file)
366 * Btree extents can be referenced by:
368 * - Different subvolumes
370 * Both the implicit back refs and the full back refs for tree blocks
371 * only consist of key. The key offset for the implicit back refs is
372 * objectid of block's owner tree. The key offset for the full back refs
373 * is the first byte of parent block.
375 * When implicit back refs is used, information about the lowest key and
376 * level of the tree block are required. These information are stored in
377 * tree block info structure.
381 * is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required,
382 * is_data == BTRFS_REF_TYPE_DATA, data type is requiried,
383 * is_data == BTRFS_REF_TYPE_ANY, either type is OK.
385 int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
386 struct btrfs_extent_inline_ref *iref,
387 enum btrfs_inline_ref_type is_data)
389 int type = btrfs_extent_inline_ref_type(eb, iref);
390 u64 offset = btrfs_extent_inline_ref_offset(eb, iref);
392 if (type == BTRFS_TREE_BLOCK_REF_KEY ||
393 type == BTRFS_SHARED_BLOCK_REF_KEY ||
394 type == BTRFS_SHARED_DATA_REF_KEY ||
395 type == BTRFS_EXTENT_DATA_REF_KEY) {
396 if (is_data == BTRFS_REF_TYPE_BLOCK) {
397 if (type == BTRFS_TREE_BLOCK_REF_KEY)
399 if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
402 * Every shared one has parent tree
403 * block, which must be aligned to
407 IS_ALIGNED(offset, eb->fs_info->nodesize))
410 } else if (is_data == BTRFS_REF_TYPE_DATA) {
411 if (type == BTRFS_EXTENT_DATA_REF_KEY)
413 if (type == BTRFS_SHARED_DATA_REF_KEY) {
416 * Every shared one has parent tree
417 * block, which must be aligned to
421 IS_ALIGNED(offset, eb->fs_info->nodesize))
425 ASSERT(is_data == BTRFS_REF_TYPE_ANY);
430 btrfs_print_leaf((struct extent_buffer *)eb);
431 btrfs_err(eb->fs_info, "eb %llu invalid extent inline ref type %d",
435 return BTRFS_REF_TYPE_INVALID;
438 u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
440 u32 high_crc = ~(u32)0;
441 u32 low_crc = ~(u32)0;
444 lenum = cpu_to_le64(root_objectid);
445 high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
446 lenum = cpu_to_le64(owner);
447 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
448 lenum = cpu_to_le64(offset);
449 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
451 return ((u64)high_crc << 31) ^ (u64)low_crc;
454 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
455 struct btrfs_extent_data_ref *ref)
457 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
458 btrfs_extent_data_ref_objectid(leaf, ref),
459 btrfs_extent_data_ref_offset(leaf, ref));
462 static int match_extent_data_ref(struct extent_buffer *leaf,
463 struct btrfs_extent_data_ref *ref,
464 u64 root_objectid, u64 owner, u64 offset)
466 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
467 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
468 btrfs_extent_data_ref_offset(leaf, ref) != offset)
473 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
474 struct btrfs_path *path,
475 u64 bytenr, u64 parent,
477 u64 owner, u64 offset)
479 struct btrfs_root *root = trans->fs_info->extent_root;
480 struct btrfs_key key;
481 struct btrfs_extent_data_ref *ref;
482 struct extent_buffer *leaf;
488 key.objectid = bytenr;
490 key.type = BTRFS_SHARED_DATA_REF_KEY;
493 key.type = BTRFS_EXTENT_DATA_REF_KEY;
494 key.offset = hash_extent_data_ref(root_objectid,
499 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
511 leaf = path->nodes[0];
512 nritems = btrfs_header_nritems(leaf);
514 if (path->slots[0] >= nritems) {
515 ret = btrfs_next_leaf(root, path);
521 leaf = path->nodes[0];
522 nritems = btrfs_header_nritems(leaf);
526 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
527 if (key.objectid != bytenr ||
528 key.type != BTRFS_EXTENT_DATA_REF_KEY)
531 ref = btrfs_item_ptr(leaf, path->slots[0],
532 struct btrfs_extent_data_ref);
534 if (match_extent_data_ref(leaf, ref, root_objectid,
537 btrfs_release_path(path);
549 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
550 struct btrfs_path *path,
551 u64 bytenr, u64 parent,
552 u64 root_objectid, u64 owner,
553 u64 offset, int refs_to_add)
555 struct btrfs_root *root = trans->fs_info->extent_root;
556 struct btrfs_key key;
557 struct extent_buffer *leaf;
562 key.objectid = bytenr;
564 key.type = BTRFS_SHARED_DATA_REF_KEY;
566 size = sizeof(struct btrfs_shared_data_ref);
568 key.type = BTRFS_EXTENT_DATA_REF_KEY;
569 key.offset = hash_extent_data_ref(root_objectid,
571 size = sizeof(struct btrfs_extent_data_ref);
574 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
575 if (ret && ret != -EEXIST)
578 leaf = path->nodes[0];
580 struct btrfs_shared_data_ref *ref;
581 ref = btrfs_item_ptr(leaf, path->slots[0],
582 struct btrfs_shared_data_ref);
584 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
586 num_refs = btrfs_shared_data_ref_count(leaf, ref);
587 num_refs += refs_to_add;
588 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
591 struct btrfs_extent_data_ref *ref;
592 while (ret == -EEXIST) {
593 ref = btrfs_item_ptr(leaf, path->slots[0],
594 struct btrfs_extent_data_ref);
595 if (match_extent_data_ref(leaf, ref, root_objectid,
598 btrfs_release_path(path);
600 ret = btrfs_insert_empty_item(trans, root, path, &key,
602 if (ret && ret != -EEXIST)
605 leaf = path->nodes[0];
607 ref = btrfs_item_ptr(leaf, path->slots[0],
608 struct btrfs_extent_data_ref);
610 btrfs_set_extent_data_ref_root(leaf, ref,
612 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
613 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
614 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
616 num_refs = btrfs_extent_data_ref_count(leaf, ref);
617 num_refs += refs_to_add;
618 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
621 btrfs_mark_buffer_dirty(leaf);
624 btrfs_release_path(path);
628 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
629 struct btrfs_path *path,
630 int refs_to_drop, int *last_ref)
632 struct btrfs_key key;
633 struct btrfs_extent_data_ref *ref1 = NULL;
634 struct btrfs_shared_data_ref *ref2 = NULL;
635 struct extent_buffer *leaf;
639 leaf = path->nodes[0];
640 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
642 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
643 ref1 = btrfs_item_ptr(leaf, path->slots[0],
644 struct btrfs_extent_data_ref);
645 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
646 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
647 ref2 = btrfs_item_ptr(leaf, path->slots[0],
648 struct btrfs_shared_data_ref);
649 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
650 } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) {
651 btrfs_print_v0_err(trans->fs_info);
652 btrfs_abort_transaction(trans, -EINVAL);
658 BUG_ON(num_refs < refs_to_drop);
659 num_refs -= refs_to_drop;
662 ret = btrfs_del_item(trans, trans->fs_info->extent_root, path);
665 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
666 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
667 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
668 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
669 btrfs_mark_buffer_dirty(leaf);
674 static noinline u32 extent_data_ref_count(struct btrfs_path *path,
675 struct btrfs_extent_inline_ref *iref)
677 struct btrfs_key key;
678 struct extent_buffer *leaf;
679 struct btrfs_extent_data_ref *ref1;
680 struct btrfs_shared_data_ref *ref2;
684 leaf = path->nodes[0];
685 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
687 BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY);
690 * If type is invalid, we should have bailed out earlier than
693 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
694 ASSERT(type != BTRFS_REF_TYPE_INVALID);
695 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
696 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
697 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
699 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
700 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
702 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
703 ref1 = btrfs_item_ptr(leaf, path->slots[0],
704 struct btrfs_extent_data_ref);
705 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
706 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
707 ref2 = btrfs_item_ptr(leaf, path->slots[0],
708 struct btrfs_shared_data_ref);
709 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
716 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
717 struct btrfs_path *path,
718 u64 bytenr, u64 parent,
721 struct btrfs_root *root = trans->fs_info->extent_root;
722 struct btrfs_key key;
725 key.objectid = bytenr;
727 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
730 key.type = BTRFS_TREE_BLOCK_REF_KEY;
731 key.offset = root_objectid;
734 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
740 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
741 struct btrfs_path *path,
742 u64 bytenr, u64 parent,
745 struct btrfs_key key;
748 key.objectid = bytenr;
750 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
753 key.type = BTRFS_TREE_BLOCK_REF_KEY;
754 key.offset = root_objectid;
757 ret = btrfs_insert_empty_item(trans, trans->fs_info->extent_root,
759 btrfs_release_path(path);
763 static inline int extent_ref_type(u64 parent, u64 owner)
766 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
768 type = BTRFS_SHARED_BLOCK_REF_KEY;
770 type = BTRFS_TREE_BLOCK_REF_KEY;
773 type = BTRFS_SHARED_DATA_REF_KEY;
775 type = BTRFS_EXTENT_DATA_REF_KEY;
780 static int find_next_key(struct btrfs_path *path, int level,
781 struct btrfs_key *key)
784 for (; level < BTRFS_MAX_LEVEL; level++) {
785 if (!path->nodes[level])
787 if (path->slots[level] + 1 >=
788 btrfs_header_nritems(path->nodes[level]))
791 btrfs_item_key_to_cpu(path->nodes[level], key,
792 path->slots[level] + 1);
794 btrfs_node_key_to_cpu(path->nodes[level], key,
795 path->slots[level] + 1);
802 * look for inline back ref. if back ref is found, *ref_ret is set
803 * to the address of inline back ref, and 0 is returned.
805 * if back ref isn't found, *ref_ret is set to the address where it
806 * should be inserted, and -ENOENT is returned.
808 * if insert is true and there are too many inline back refs, the path
809 * points to the extent item, and -EAGAIN is returned.
811 * NOTE: inline back refs are ordered in the same way that back ref
812 * items in the tree are ordered.
814 static noinline_for_stack
815 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
816 struct btrfs_path *path,
817 struct btrfs_extent_inline_ref **ref_ret,
818 u64 bytenr, u64 num_bytes,
819 u64 parent, u64 root_objectid,
820 u64 owner, u64 offset, int insert)
822 struct btrfs_fs_info *fs_info = trans->fs_info;
823 struct btrfs_root *root = fs_info->extent_root;
824 struct btrfs_key key;
825 struct extent_buffer *leaf;
826 struct btrfs_extent_item *ei;
827 struct btrfs_extent_inline_ref *iref;
837 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
840 key.objectid = bytenr;
841 key.type = BTRFS_EXTENT_ITEM_KEY;
842 key.offset = num_bytes;
844 want = extent_ref_type(parent, owner);
846 extra_size = btrfs_extent_inline_ref_size(want);
847 path->keep_locks = 1;
852 * Owner is our level, so we can just add one to get the level for the
853 * block we are interested in.
855 if (skinny_metadata && owner < BTRFS_FIRST_FREE_OBJECTID) {
856 key.type = BTRFS_METADATA_ITEM_KEY;
861 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
868 * We may be a newly converted file system which still has the old fat
869 * extent entries for metadata, so try and see if we have one of those.
871 if (ret > 0 && skinny_metadata) {
872 skinny_metadata = false;
873 if (path->slots[0]) {
875 btrfs_item_key_to_cpu(path->nodes[0], &key,
877 if (key.objectid == bytenr &&
878 key.type == BTRFS_EXTENT_ITEM_KEY &&
879 key.offset == num_bytes)
883 key.objectid = bytenr;
884 key.type = BTRFS_EXTENT_ITEM_KEY;
885 key.offset = num_bytes;
886 btrfs_release_path(path);
891 if (ret && !insert) {
894 } else if (WARN_ON(ret)) {
899 leaf = path->nodes[0];
900 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
901 if (unlikely(item_size < sizeof(*ei))) {
903 btrfs_print_v0_err(fs_info);
904 btrfs_abort_transaction(trans, err);
908 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
909 flags = btrfs_extent_flags(leaf, ei);
911 ptr = (unsigned long)(ei + 1);
912 end = (unsigned long)ei + item_size;
914 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
915 ptr += sizeof(struct btrfs_tree_block_info);
919 if (owner >= BTRFS_FIRST_FREE_OBJECTID)
920 needed = BTRFS_REF_TYPE_DATA;
922 needed = BTRFS_REF_TYPE_BLOCK;
930 iref = (struct btrfs_extent_inline_ref *)ptr;
931 type = btrfs_get_extent_inline_ref_type(leaf, iref, needed);
932 if (type == BTRFS_REF_TYPE_INVALID) {
940 ptr += btrfs_extent_inline_ref_size(type);
944 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
945 struct btrfs_extent_data_ref *dref;
946 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
947 if (match_extent_data_ref(leaf, dref, root_objectid,
952 if (hash_extent_data_ref_item(leaf, dref) <
953 hash_extent_data_ref(root_objectid, owner, offset))
957 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
959 if (parent == ref_offset) {
963 if (ref_offset < parent)
966 if (root_objectid == ref_offset) {
970 if (ref_offset < root_objectid)
974 ptr += btrfs_extent_inline_ref_size(type);
976 if (err == -ENOENT && insert) {
977 if (item_size + extra_size >=
978 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
983 * To add new inline back ref, we have to make sure
984 * there is no corresponding back ref item.
985 * For simplicity, we just do not add new inline back
986 * ref if there is any kind of item for this block
988 if (find_next_key(path, 0, &key) == 0 &&
989 key.objectid == bytenr &&
990 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
995 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
998 path->keep_locks = 0;
999 btrfs_unlock_up_safe(path, 1);
1005 * helper to add new inline back ref
1007 static noinline_for_stack
1008 void setup_inline_extent_backref(struct btrfs_fs_info *fs_info,
1009 struct btrfs_path *path,
1010 struct btrfs_extent_inline_ref *iref,
1011 u64 parent, u64 root_objectid,
1012 u64 owner, u64 offset, int refs_to_add,
1013 struct btrfs_delayed_extent_op *extent_op)
1015 struct extent_buffer *leaf;
1016 struct btrfs_extent_item *ei;
1019 unsigned long item_offset;
1024 leaf = path->nodes[0];
1025 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1026 item_offset = (unsigned long)iref - (unsigned long)ei;
1028 type = extent_ref_type(parent, owner);
1029 size = btrfs_extent_inline_ref_size(type);
1031 btrfs_extend_item(path, size);
1033 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1034 refs = btrfs_extent_refs(leaf, ei);
1035 refs += refs_to_add;
1036 btrfs_set_extent_refs(leaf, ei, refs);
1038 __run_delayed_extent_op(extent_op, leaf, ei);
1040 ptr = (unsigned long)ei + item_offset;
1041 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1042 if (ptr < end - size)
1043 memmove_extent_buffer(leaf, ptr + size, ptr,
1046 iref = (struct btrfs_extent_inline_ref *)ptr;
1047 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1048 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1049 struct btrfs_extent_data_ref *dref;
1050 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1051 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1052 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1053 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1054 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1055 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1056 struct btrfs_shared_data_ref *sref;
1057 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1058 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1059 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1060 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1061 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1063 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1065 btrfs_mark_buffer_dirty(leaf);
1068 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1069 struct btrfs_path *path,
1070 struct btrfs_extent_inline_ref **ref_ret,
1071 u64 bytenr, u64 num_bytes, u64 parent,
1072 u64 root_objectid, u64 owner, u64 offset)
1076 ret = lookup_inline_extent_backref(trans, path, ref_ret, bytenr,
1077 num_bytes, parent, root_objectid,
1082 btrfs_release_path(path);
1085 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1086 ret = lookup_tree_block_ref(trans, path, bytenr, parent,
1089 ret = lookup_extent_data_ref(trans, path, bytenr, parent,
1090 root_objectid, owner, offset);
1096 * helper to update/remove inline back ref
1098 static noinline_for_stack
1099 void update_inline_extent_backref(struct btrfs_path *path,
1100 struct btrfs_extent_inline_ref *iref,
1102 struct btrfs_delayed_extent_op *extent_op,
1105 struct extent_buffer *leaf = path->nodes[0];
1106 struct btrfs_extent_item *ei;
1107 struct btrfs_extent_data_ref *dref = NULL;
1108 struct btrfs_shared_data_ref *sref = NULL;
1116 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1117 refs = btrfs_extent_refs(leaf, ei);
1118 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1119 refs += refs_to_mod;
1120 btrfs_set_extent_refs(leaf, ei, refs);
1122 __run_delayed_extent_op(extent_op, leaf, ei);
1125 * If type is invalid, we should have bailed out after
1126 * lookup_inline_extent_backref().
1128 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_ANY);
1129 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1131 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1132 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1133 refs = btrfs_extent_data_ref_count(leaf, dref);
1134 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1135 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1136 refs = btrfs_shared_data_ref_count(leaf, sref);
1139 BUG_ON(refs_to_mod != -1);
1142 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1143 refs += refs_to_mod;
1146 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1147 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1149 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1152 size = btrfs_extent_inline_ref_size(type);
1153 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1154 ptr = (unsigned long)iref;
1155 end = (unsigned long)ei + item_size;
1156 if (ptr + size < end)
1157 memmove_extent_buffer(leaf, ptr, ptr + size,
1160 btrfs_truncate_item(path, item_size, 1);
1162 btrfs_mark_buffer_dirty(leaf);
1165 static noinline_for_stack
1166 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1167 struct btrfs_path *path,
1168 u64 bytenr, u64 num_bytes, u64 parent,
1169 u64 root_objectid, u64 owner,
1170 u64 offset, int refs_to_add,
1171 struct btrfs_delayed_extent_op *extent_op)
1173 struct btrfs_extent_inline_ref *iref;
1176 ret = lookup_inline_extent_backref(trans, path, &iref, bytenr,
1177 num_bytes, parent, root_objectid,
1180 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1181 update_inline_extent_backref(path, iref, refs_to_add,
1183 } else if (ret == -ENOENT) {
1184 setup_inline_extent_backref(trans->fs_info, path, iref, parent,
1185 root_objectid, owner, offset,
1186 refs_to_add, extent_op);
1192 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1193 struct btrfs_path *path,
1194 struct btrfs_extent_inline_ref *iref,
1195 int refs_to_drop, int is_data, int *last_ref)
1199 BUG_ON(!is_data && refs_to_drop != 1);
1201 update_inline_extent_backref(path, iref, -refs_to_drop, NULL,
1203 } else if (is_data) {
1204 ret = remove_extent_data_ref(trans, path, refs_to_drop,
1208 ret = btrfs_del_item(trans, trans->fs_info->extent_root, path);
1213 static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len,
1214 u64 *discarded_bytes)
1217 u64 bytes_left, end;
1218 u64 aligned_start = ALIGN(start, 1 << 9);
1220 if (WARN_ON(start != aligned_start)) {
1221 len -= aligned_start - start;
1222 len = round_down(len, 1 << 9);
1223 start = aligned_start;
1226 *discarded_bytes = 0;
1234 /* Skip any superblocks on this device. */
1235 for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) {
1236 u64 sb_start = btrfs_sb_offset(j);
1237 u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE;
1238 u64 size = sb_start - start;
1240 if (!in_range(sb_start, start, bytes_left) &&
1241 !in_range(sb_end, start, bytes_left) &&
1242 !in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE))
1246 * Superblock spans beginning of range. Adjust start and
1249 if (sb_start <= start) {
1250 start += sb_end - start;
1255 bytes_left = end - start;
1260 ret = blkdev_issue_discard(bdev, start >> 9, size >> 9,
1263 *discarded_bytes += size;
1264 else if (ret != -EOPNOTSUPP)
1273 bytes_left = end - start;
1277 ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9,
1280 *discarded_bytes += bytes_left;
1285 int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
1286 u64 num_bytes, u64 *actual_bytes)
1289 u64 discarded_bytes = 0;
1290 u64 end = bytenr + num_bytes;
1292 struct btrfs_bio *bbio = NULL;
1296 * Avoid races with device replace and make sure our bbio has devices
1297 * associated to its stripes that don't go away while we are discarding.
1299 btrfs_bio_counter_inc_blocked(fs_info);
1301 struct btrfs_bio_stripe *stripe;
1304 num_bytes = end - cur;
1305 /* Tell the block device(s) that the sectors can be discarded */
1306 ret = btrfs_map_block(fs_info, BTRFS_MAP_DISCARD, cur,
1307 &num_bytes, &bbio, 0);
1309 * Error can be -ENOMEM, -ENOENT (no such chunk mapping) or
1310 * -EOPNOTSUPP. For any such error, @num_bytes is not updated,
1311 * thus we can't continue anyway.
1316 stripe = bbio->stripes;
1317 for (i = 0; i < bbio->num_stripes; i++, stripe++) {
1319 struct request_queue *req_q;
1321 if (!stripe->dev->bdev) {
1322 ASSERT(btrfs_test_opt(fs_info, DEGRADED));
1325 req_q = bdev_get_queue(stripe->dev->bdev);
1326 if (!blk_queue_discard(req_q))
1329 ret = btrfs_issue_discard(stripe->dev->bdev,
1334 discarded_bytes += bytes;
1335 } else if (ret != -EOPNOTSUPP) {
1337 * Logic errors or -ENOMEM, or -EIO, but
1338 * unlikely to happen.
1340 * And since there are two loops, explicitly
1341 * go to out to avoid confusion.
1343 btrfs_put_bbio(bbio);
1348 * Just in case we get back EOPNOTSUPP for some reason,
1349 * just ignore the return value so we don't screw up
1350 * people calling discard_extent.
1354 btrfs_put_bbio(bbio);
1358 btrfs_bio_counter_dec(fs_info);
1361 *actual_bytes = discarded_bytes;
1364 if (ret == -EOPNOTSUPP)
1369 /* Can return -ENOMEM */
1370 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1371 struct btrfs_ref *generic_ref)
1373 struct btrfs_fs_info *fs_info = trans->fs_info;
1374 int old_ref_mod, new_ref_mod;
1377 ASSERT(generic_ref->type != BTRFS_REF_NOT_SET &&
1378 generic_ref->action);
1379 BUG_ON(generic_ref->type == BTRFS_REF_METADATA &&
1380 generic_ref->tree_ref.root == BTRFS_TREE_LOG_OBJECTID);
1382 if (generic_ref->type == BTRFS_REF_METADATA)
1383 ret = btrfs_add_delayed_tree_ref(trans, generic_ref,
1384 NULL, &old_ref_mod, &new_ref_mod);
1386 ret = btrfs_add_delayed_data_ref(trans, generic_ref, 0,
1387 &old_ref_mod, &new_ref_mod);
1389 btrfs_ref_tree_mod(fs_info, generic_ref);
1391 if (ret == 0 && old_ref_mod < 0 && new_ref_mod >= 0)
1392 sub_pinned_bytes(fs_info, generic_ref);
1398 * __btrfs_inc_extent_ref - insert backreference for a given extent
1400 * @trans: Handle of transaction
1402 * @node: The delayed ref node used to get the bytenr/length for
1403 * extent whose references are incremented.
1405 * @parent: If this is a shared extent (BTRFS_SHARED_DATA_REF_KEY/
1406 * BTRFS_SHARED_BLOCK_REF_KEY) then it holds the logical
1407 * bytenr of the parent block. Since new extents are always
1408 * created with indirect references, this will only be the case
1409 * when relocating a shared extent. In that case, root_objectid
1410 * will be BTRFS_TREE_RELOC_OBJECTID. Otheriwse, parent must
1413 * @root_objectid: The id of the root where this modification has originated,
1414 * this can be either one of the well-known metadata trees or
1415 * the subvolume id which references this extent.
1417 * @owner: For data extents it is the inode number of the owning file.
1418 * For metadata extents this parameter holds the level in the
1419 * tree of the extent.
1421 * @offset: For metadata extents the offset is ignored and is currently
1422 * always passed as 0. For data extents it is the fileoffset
1423 * this extent belongs to.
1425 * @refs_to_add Number of references to add
1427 * @extent_op Pointer to a structure, holding information necessary when
1428 * updating a tree block's flags
1431 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1432 struct btrfs_delayed_ref_node *node,
1433 u64 parent, u64 root_objectid,
1434 u64 owner, u64 offset, int refs_to_add,
1435 struct btrfs_delayed_extent_op *extent_op)
1437 struct btrfs_path *path;
1438 struct extent_buffer *leaf;
1439 struct btrfs_extent_item *item;
1440 struct btrfs_key key;
1441 u64 bytenr = node->bytenr;
1442 u64 num_bytes = node->num_bytes;
1446 path = btrfs_alloc_path();
1450 path->leave_spinning = 1;
1451 /* this will setup the path even if it fails to insert the back ref */
1452 ret = insert_inline_extent_backref(trans, path, bytenr, num_bytes,
1453 parent, root_objectid, owner,
1454 offset, refs_to_add, extent_op);
1455 if ((ret < 0 && ret != -EAGAIN) || !ret)
1459 * Ok we had -EAGAIN which means we didn't have space to insert and
1460 * inline extent ref, so just update the reference count and add a
1463 leaf = path->nodes[0];
1464 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1465 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1466 refs = btrfs_extent_refs(leaf, item);
1467 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1469 __run_delayed_extent_op(extent_op, leaf, item);
1471 btrfs_mark_buffer_dirty(leaf);
1472 btrfs_release_path(path);
1474 path->leave_spinning = 1;
1475 /* now insert the actual backref */
1476 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1477 BUG_ON(refs_to_add != 1);
1478 ret = insert_tree_block_ref(trans, path, bytenr, parent,
1481 ret = insert_extent_data_ref(trans, path, bytenr, parent,
1482 root_objectid, owner, offset,
1486 btrfs_abort_transaction(trans, ret);
1488 btrfs_free_path(path);
1492 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1493 struct btrfs_delayed_ref_node *node,
1494 struct btrfs_delayed_extent_op *extent_op,
1495 int insert_reserved)
1498 struct btrfs_delayed_data_ref *ref;
1499 struct btrfs_key ins;
1504 ins.objectid = node->bytenr;
1505 ins.offset = node->num_bytes;
1506 ins.type = BTRFS_EXTENT_ITEM_KEY;
1508 ref = btrfs_delayed_node_to_data_ref(node);
1509 trace_run_delayed_data_ref(trans->fs_info, node, ref, node->action);
1511 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1512 parent = ref->parent;
1513 ref_root = ref->root;
1515 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1517 flags |= extent_op->flags_to_set;
1518 ret = alloc_reserved_file_extent(trans, parent, ref_root,
1519 flags, ref->objectid,
1522 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1523 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
1524 ref->objectid, ref->offset,
1525 node->ref_mod, extent_op);
1526 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1527 ret = __btrfs_free_extent(trans, node, parent,
1528 ref_root, ref->objectid,
1529 ref->offset, node->ref_mod,
1537 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1538 struct extent_buffer *leaf,
1539 struct btrfs_extent_item *ei)
1541 u64 flags = btrfs_extent_flags(leaf, ei);
1542 if (extent_op->update_flags) {
1543 flags |= extent_op->flags_to_set;
1544 btrfs_set_extent_flags(leaf, ei, flags);
1547 if (extent_op->update_key) {
1548 struct btrfs_tree_block_info *bi;
1549 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1550 bi = (struct btrfs_tree_block_info *)(ei + 1);
1551 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1555 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1556 struct btrfs_delayed_ref_head *head,
1557 struct btrfs_delayed_extent_op *extent_op)
1559 struct btrfs_fs_info *fs_info = trans->fs_info;
1560 struct btrfs_key key;
1561 struct btrfs_path *path;
1562 struct btrfs_extent_item *ei;
1563 struct extent_buffer *leaf;
1567 int metadata = !extent_op->is_data;
1569 if (TRANS_ABORTED(trans))
1572 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA))
1575 path = btrfs_alloc_path();
1579 key.objectid = head->bytenr;
1582 key.type = BTRFS_METADATA_ITEM_KEY;
1583 key.offset = extent_op->level;
1585 key.type = BTRFS_EXTENT_ITEM_KEY;
1586 key.offset = head->num_bytes;
1590 path->leave_spinning = 1;
1591 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 1);
1598 if (path->slots[0] > 0) {
1600 btrfs_item_key_to_cpu(path->nodes[0], &key,
1602 if (key.objectid == head->bytenr &&
1603 key.type == BTRFS_EXTENT_ITEM_KEY &&
1604 key.offset == head->num_bytes)
1608 btrfs_release_path(path);
1611 key.objectid = head->bytenr;
1612 key.offset = head->num_bytes;
1613 key.type = BTRFS_EXTENT_ITEM_KEY;
1622 leaf = path->nodes[0];
1623 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1625 if (unlikely(item_size < sizeof(*ei))) {
1627 btrfs_print_v0_err(fs_info);
1628 btrfs_abort_transaction(trans, err);
1632 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1633 __run_delayed_extent_op(extent_op, leaf, ei);
1635 btrfs_mark_buffer_dirty(leaf);
1637 btrfs_free_path(path);
1641 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1642 struct btrfs_delayed_ref_node *node,
1643 struct btrfs_delayed_extent_op *extent_op,
1644 int insert_reserved)
1647 struct btrfs_delayed_tree_ref *ref;
1651 ref = btrfs_delayed_node_to_tree_ref(node);
1652 trace_run_delayed_tree_ref(trans->fs_info, node, ref, node->action);
1654 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1655 parent = ref->parent;
1656 ref_root = ref->root;
1658 if (node->ref_mod != 1) {
1659 btrfs_err(trans->fs_info,
1660 "btree block(%llu) has %d references rather than 1: action %d ref_root %llu parent %llu",
1661 node->bytenr, node->ref_mod, node->action, ref_root,
1665 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1666 BUG_ON(!extent_op || !extent_op->update_flags);
1667 ret = alloc_reserved_tree_block(trans, node, extent_op);
1668 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1669 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
1670 ref->level, 0, 1, extent_op);
1671 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1672 ret = __btrfs_free_extent(trans, node, parent, ref_root,
1673 ref->level, 0, 1, extent_op);
1680 /* helper function to actually process a single delayed ref entry */
1681 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
1682 struct btrfs_delayed_ref_node *node,
1683 struct btrfs_delayed_extent_op *extent_op,
1684 int insert_reserved)
1688 if (TRANS_ABORTED(trans)) {
1689 if (insert_reserved)
1690 btrfs_pin_extent(trans, node->bytenr, node->num_bytes, 1);
1694 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
1695 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1696 ret = run_delayed_tree_ref(trans, node, extent_op,
1698 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
1699 node->type == BTRFS_SHARED_DATA_REF_KEY)
1700 ret = run_delayed_data_ref(trans, node, extent_op,
1704 if (ret && insert_reserved)
1705 btrfs_pin_extent(trans, node->bytenr, node->num_bytes, 1);
1709 static inline struct btrfs_delayed_ref_node *
1710 select_delayed_ref(struct btrfs_delayed_ref_head *head)
1712 struct btrfs_delayed_ref_node *ref;
1714 if (RB_EMPTY_ROOT(&head->ref_tree.rb_root))
1718 * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
1719 * This is to prevent a ref count from going down to zero, which deletes
1720 * the extent item from the extent tree, when there still are references
1721 * to add, which would fail because they would not find the extent item.
1723 if (!list_empty(&head->ref_add_list))
1724 return list_first_entry(&head->ref_add_list,
1725 struct btrfs_delayed_ref_node, add_list);
1727 ref = rb_entry(rb_first_cached(&head->ref_tree),
1728 struct btrfs_delayed_ref_node, ref_node);
1729 ASSERT(list_empty(&ref->add_list));
1733 static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
1734 struct btrfs_delayed_ref_head *head)
1736 spin_lock(&delayed_refs->lock);
1737 head->processing = 0;
1738 delayed_refs->num_heads_ready++;
1739 spin_unlock(&delayed_refs->lock);
1740 btrfs_delayed_ref_unlock(head);
1743 static struct btrfs_delayed_extent_op *cleanup_extent_op(
1744 struct btrfs_delayed_ref_head *head)
1746 struct btrfs_delayed_extent_op *extent_op = head->extent_op;
1751 if (head->must_insert_reserved) {
1752 head->extent_op = NULL;
1753 btrfs_free_delayed_extent_op(extent_op);
1759 static int run_and_cleanup_extent_op(struct btrfs_trans_handle *trans,
1760 struct btrfs_delayed_ref_head *head)
1762 struct btrfs_delayed_extent_op *extent_op;
1765 extent_op = cleanup_extent_op(head);
1768 head->extent_op = NULL;
1769 spin_unlock(&head->lock);
1770 ret = run_delayed_extent_op(trans, head, extent_op);
1771 btrfs_free_delayed_extent_op(extent_op);
1772 return ret ? ret : 1;
1775 void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
1776 struct btrfs_delayed_ref_root *delayed_refs,
1777 struct btrfs_delayed_ref_head *head)
1779 int nr_items = 1; /* Dropping this ref head update. */
1781 if (head->total_ref_mod < 0) {
1782 struct btrfs_space_info *space_info;
1786 flags = BTRFS_BLOCK_GROUP_DATA;
1787 else if (head->is_system)
1788 flags = BTRFS_BLOCK_GROUP_SYSTEM;
1790 flags = BTRFS_BLOCK_GROUP_METADATA;
1791 space_info = btrfs_find_space_info(fs_info, flags);
1793 percpu_counter_add_batch(&space_info->total_bytes_pinned,
1795 BTRFS_TOTAL_BYTES_PINNED_BATCH);
1798 * We had csum deletions accounted for in our delayed refs rsv,
1799 * we need to drop the csum leaves for this update from our
1802 if (head->is_data) {
1803 spin_lock(&delayed_refs->lock);
1804 delayed_refs->pending_csums -= head->num_bytes;
1805 spin_unlock(&delayed_refs->lock);
1806 nr_items += btrfs_csum_bytes_to_leaves(fs_info,
1811 btrfs_delayed_refs_rsv_release(fs_info, nr_items);
1814 static int cleanup_ref_head(struct btrfs_trans_handle *trans,
1815 struct btrfs_delayed_ref_head *head)
1818 struct btrfs_fs_info *fs_info = trans->fs_info;
1819 struct btrfs_delayed_ref_root *delayed_refs;
1822 delayed_refs = &trans->transaction->delayed_refs;
1824 ret = run_and_cleanup_extent_op(trans, head);
1826 unselect_delayed_ref_head(delayed_refs, head);
1827 btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);
1834 * Need to drop our head ref lock and re-acquire the delayed ref lock
1835 * and then re-check to make sure nobody got added.
1837 spin_unlock(&head->lock);
1838 spin_lock(&delayed_refs->lock);
1839 spin_lock(&head->lock);
1840 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root) || head->extent_op) {
1841 spin_unlock(&head->lock);
1842 spin_unlock(&delayed_refs->lock);
1845 btrfs_delete_ref_head(delayed_refs, head);
1846 spin_unlock(&head->lock);
1847 spin_unlock(&delayed_refs->lock);
1849 if (head->must_insert_reserved) {
1850 btrfs_pin_extent(trans, head->bytenr, head->num_bytes, 1);
1851 if (head->is_data) {
1852 ret = btrfs_del_csums(trans, fs_info->csum_root,
1853 head->bytenr, head->num_bytes);
1857 btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
1859 trace_run_delayed_ref_head(fs_info, head, 0);
1860 btrfs_delayed_ref_unlock(head);
1861 btrfs_put_delayed_ref_head(head);
1865 static struct btrfs_delayed_ref_head *btrfs_obtain_ref_head(
1866 struct btrfs_trans_handle *trans)
1868 struct btrfs_delayed_ref_root *delayed_refs =
1869 &trans->transaction->delayed_refs;
1870 struct btrfs_delayed_ref_head *head = NULL;
1873 spin_lock(&delayed_refs->lock);
1874 head = btrfs_select_ref_head(delayed_refs);
1876 spin_unlock(&delayed_refs->lock);
1881 * Grab the lock that says we are going to process all the refs for
1884 ret = btrfs_delayed_ref_lock(delayed_refs, head);
1885 spin_unlock(&delayed_refs->lock);
1888 * We may have dropped the spin lock to get the head mutex lock, and
1889 * that might have given someone else time to free the head. If that's
1890 * true, it has been removed from our list and we can move on.
1893 head = ERR_PTR(-EAGAIN);
1898 static int btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle *trans,
1899 struct btrfs_delayed_ref_head *locked_ref,
1900 unsigned long *run_refs)
1902 struct btrfs_fs_info *fs_info = trans->fs_info;
1903 struct btrfs_delayed_ref_root *delayed_refs;
1904 struct btrfs_delayed_extent_op *extent_op;
1905 struct btrfs_delayed_ref_node *ref;
1906 int must_insert_reserved = 0;
1909 delayed_refs = &trans->transaction->delayed_refs;
1911 lockdep_assert_held(&locked_ref->mutex);
1912 lockdep_assert_held(&locked_ref->lock);
1914 while ((ref = select_delayed_ref(locked_ref))) {
1916 btrfs_check_delayed_seq(fs_info, ref->seq)) {
1917 spin_unlock(&locked_ref->lock);
1918 unselect_delayed_ref_head(delayed_refs, locked_ref);
1924 rb_erase_cached(&ref->ref_node, &locked_ref->ref_tree);
1925 RB_CLEAR_NODE(&ref->ref_node);
1926 if (!list_empty(&ref->add_list))
1927 list_del(&ref->add_list);
1929 * When we play the delayed ref, also correct the ref_mod on
1932 switch (ref->action) {
1933 case BTRFS_ADD_DELAYED_REF:
1934 case BTRFS_ADD_DELAYED_EXTENT:
1935 locked_ref->ref_mod -= ref->ref_mod;
1937 case BTRFS_DROP_DELAYED_REF:
1938 locked_ref->ref_mod += ref->ref_mod;
1943 atomic_dec(&delayed_refs->num_entries);
1946 * Record the must_insert_reserved flag before we drop the
1949 must_insert_reserved = locked_ref->must_insert_reserved;
1950 locked_ref->must_insert_reserved = 0;
1952 extent_op = locked_ref->extent_op;
1953 locked_ref->extent_op = NULL;
1954 spin_unlock(&locked_ref->lock);
1956 ret = run_one_delayed_ref(trans, ref, extent_op,
1957 must_insert_reserved);
1959 btrfs_free_delayed_extent_op(extent_op);
1961 unselect_delayed_ref_head(delayed_refs, locked_ref);
1962 btrfs_put_delayed_ref(ref);
1963 btrfs_debug(fs_info, "run_one_delayed_ref returned %d",
1968 btrfs_put_delayed_ref(ref);
1971 spin_lock(&locked_ref->lock);
1972 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
1979 * Returns 0 on success or if called with an already aborted transaction.
1980 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
1982 static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
1985 struct btrfs_fs_info *fs_info = trans->fs_info;
1986 struct btrfs_delayed_ref_root *delayed_refs;
1987 struct btrfs_delayed_ref_head *locked_ref = NULL;
1988 ktime_t start = ktime_get();
1990 unsigned long count = 0;
1991 unsigned long actual_count = 0;
1993 delayed_refs = &trans->transaction->delayed_refs;
1996 locked_ref = btrfs_obtain_ref_head(trans);
1997 if (IS_ERR_OR_NULL(locked_ref)) {
1998 if (PTR_ERR(locked_ref) == -EAGAIN) {
2007 * We need to try and merge add/drops of the same ref since we
2008 * can run into issues with relocate dropping the implicit ref
2009 * and then it being added back again before the drop can
2010 * finish. If we merged anything we need to re-loop so we can
2012 * Or we can get node references of the same type that weren't
2013 * merged when created due to bumps in the tree mod seq, and
2014 * we need to merge them to prevent adding an inline extent
2015 * backref before dropping it (triggering a BUG_ON at
2016 * insert_inline_extent_backref()).
2018 spin_lock(&locked_ref->lock);
2019 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
2021 ret = btrfs_run_delayed_refs_for_head(trans, locked_ref,
2023 if (ret < 0 && ret != -EAGAIN) {
2025 * Error, btrfs_run_delayed_refs_for_head already
2026 * unlocked everything so just bail out
2031 * Success, perform the usual cleanup of a processed
2034 ret = cleanup_ref_head(trans, locked_ref);
2036 /* We dropped our lock, we need to loop. */
2045 * Either success case or btrfs_run_delayed_refs_for_head
2046 * returned -EAGAIN, meaning we need to select another head
2051 } while ((nr != -1 && count < nr) || locked_ref);
2054 * We don't want to include ref heads since we can have empty ref heads
2055 * and those will drastically skew our runtime down since we just do
2056 * accounting, no actual extent tree updates.
2058 if (actual_count > 0) {
2059 u64 runtime = ktime_to_ns(ktime_sub(ktime_get(), start));
2063 * We weigh the current average higher than our current runtime
2064 * to avoid large swings in the average.
2066 spin_lock(&delayed_refs->lock);
2067 avg = fs_info->avg_delayed_ref_runtime * 3 + runtime;
2068 fs_info->avg_delayed_ref_runtime = avg >> 2; /* div by 4 */
2069 spin_unlock(&delayed_refs->lock);
2074 #ifdef SCRAMBLE_DELAYED_REFS
2076 * Normally delayed refs get processed in ascending bytenr order. This
2077 * correlates in most cases to the order added. To expose dependencies on this
2078 * order, we start to process the tree in the middle instead of the beginning
2080 static u64 find_middle(struct rb_root *root)
2082 struct rb_node *n = root->rb_node;
2083 struct btrfs_delayed_ref_node *entry;
2086 u64 first = 0, last = 0;
2090 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2091 first = entry->bytenr;
2095 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2096 last = entry->bytenr;
2101 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2102 WARN_ON(!entry->in_tree);
2104 middle = entry->bytenr;
2118 * Takes the number of bytes to be csumm'ed and figures out how many leaves it
2119 * would require to store the csums for that many bytes.
2121 u64 btrfs_csum_bytes_to_leaves(struct btrfs_fs_info *fs_info, u64 csum_bytes)
2124 u64 num_csums_per_leaf;
2127 csum_size = BTRFS_MAX_ITEM_SIZE(fs_info);
2128 num_csums_per_leaf = div64_u64(csum_size,
2129 (u64)btrfs_super_csum_size(fs_info->super_copy));
2130 num_csums = div64_u64(csum_bytes, fs_info->sectorsize);
2131 num_csums += num_csums_per_leaf - 1;
2132 num_csums = div64_u64(num_csums, num_csums_per_leaf);
2137 * this starts processing the delayed reference count updates and
2138 * extent insertions we have queued up so far. count can be
2139 * 0, which means to process everything in the tree at the start
2140 * of the run (but not newly added entries), or it can be some target
2141 * number you'd like to process.
2143 * Returns 0 on success or if called with an aborted transaction
2144 * Returns <0 on error and aborts the transaction
2146 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2147 unsigned long count)
2149 struct btrfs_fs_info *fs_info = trans->fs_info;
2150 struct rb_node *node;
2151 struct btrfs_delayed_ref_root *delayed_refs;
2152 struct btrfs_delayed_ref_head *head;
2154 int run_all = count == (unsigned long)-1;
2156 /* We'll clean this up in btrfs_cleanup_transaction */
2157 if (TRANS_ABORTED(trans))
2160 if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags))
2163 delayed_refs = &trans->transaction->delayed_refs;
2165 count = atomic_read(&delayed_refs->num_entries) * 2;
2168 #ifdef SCRAMBLE_DELAYED_REFS
2169 delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
2171 ret = __btrfs_run_delayed_refs(trans, count);
2173 btrfs_abort_transaction(trans, ret);
2178 btrfs_create_pending_block_groups(trans);
2180 spin_lock(&delayed_refs->lock);
2181 node = rb_first_cached(&delayed_refs->href_root);
2183 spin_unlock(&delayed_refs->lock);
2186 head = rb_entry(node, struct btrfs_delayed_ref_head,
2188 refcount_inc(&head->refs);
2189 spin_unlock(&delayed_refs->lock);
2191 /* Mutex was contended, block until it's released and retry. */
2192 mutex_lock(&head->mutex);
2193 mutex_unlock(&head->mutex);
2195 btrfs_put_delayed_ref_head(head);
2203 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2204 struct extent_buffer *eb, u64 flags,
2205 int level, int is_data)
2207 struct btrfs_delayed_extent_op *extent_op;
2210 extent_op = btrfs_alloc_delayed_extent_op();
2214 extent_op->flags_to_set = flags;
2215 extent_op->update_flags = true;
2216 extent_op->update_key = false;
2217 extent_op->is_data = is_data ? true : false;
2218 extent_op->level = level;
2220 ret = btrfs_add_delayed_extent_op(trans, eb->start, eb->len, extent_op);
2222 btrfs_free_delayed_extent_op(extent_op);
2226 static noinline int check_delayed_ref(struct btrfs_root *root,
2227 struct btrfs_path *path,
2228 u64 objectid, u64 offset, u64 bytenr)
2230 struct btrfs_delayed_ref_head *head;
2231 struct btrfs_delayed_ref_node *ref;
2232 struct btrfs_delayed_data_ref *data_ref;
2233 struct btrfs_delayed_ref_root *delayed_refs;
2234 struct btrfs_transaction *cur_trans;
2235 struct rb_node *node;
2238 spin_lock(&root->fs_info->trans_lock);
2239 cur_trans = root->fs_info->running_transaction;
2241 refcount_inc(&cur_trans->use_count);
2242 spin_unlock(&root->fs_info->trans_lock);
2246 delayed_refs = &cur_trans->delayed_refs;
2247 spin_lock(&delayed_refs->lock);
2248 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
2250 spin_unlock(&delayed_refs->lock);
2251 btrfs_put_transaction(cur_trans);
2255 if (!mutex_trylock(&head->mutex)) {
2256 refcount_inc(&head->refs);
2257 spin_unlock(&delayed_refs->lock);
2259 btrfs_release_path(path);
2262 * Mutex was contended, block until it's released and let
2265 mutex_lock(&head->mutex);
2266 mutex_unlock(&head->mutex);
2267 btrfs_put_delayed_ref_head(head);
2268 btrfs_put_transaction(cur_trans);
2271 spin_unlock(&delayed_refs->lock);
2273 spin_lock(&head->lock);
2275 * XXX: We should replace this with a proper search function in the
2278 for (node = rb_first_cached(&head->ref_tree); node;
2279 node = rb_next(node)) {
2280 ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
2281 /* If it's a shared ref we know a cross reference exists */
2282 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) {
2287 data_ref = btrfs_delayed_node_to_data_ref(ref);
2290 * If our ref doesn't match the one we're currently looking at
2291 * then we have a cross reference.
2293 if (data_ref->root != root->root_key.objectid ||
2294 data_ref->objectid != objectid ||
2295 data_ref->offset != offset) {
2300 spin_unlock(&head->lock);
2301 mutex_unlock(&head->mutex);
2302 btrfs_put_transaction(cur_trans);
2306 static noinline int check_committed_ref(struct btrfs_root *root,
2307 struct btrfs_path *path,
2308 u64 objectid, u64 offset, u64 bytenr)
2310 struct btrfs_fs_info *fs_info = root->fs_info;
2311 struct btrfs_root *extent_root = fs_info->extent_root;
2312 struct extent_buffer *leaf;
2313 struct btrfs_extent_data_ref *ref;
2314 struct btrfs_extent_inline_ref *iref;
2315 struct btrfs_extent_item *ei;
2316 struct btrfs_key key;
2321 key.objectid = bytenr;
2322 key.offset = (u64)-1;
2323 key.type = BTRFS_EXTENT_ITEM_KEY;
2325 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2328 BUG_ON(ret == 0); /* Corruption */
2331 if (path->slots[0] == 0)
2335 leaf = path->nodes[0];
2336 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2338 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2342 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2343 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2345 /* If extent item has more than 1 inline ref then it's shared */
2346 if (item_size != sizeof(*ei) +
2347 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2350 /* If extent created before last snapshot => it's definitely shared */
2351 if (btrfs_extent_generation(leaf, ei) <=
2352 btrfs_root_last_snapshot(&root->root_item))
2355 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2357 /* If this extent has SHARED_DATA_REF then it's shared */
2358 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
2359 if (type != BTRFS_EXTENT_DATA_REF_KEY)
2362 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2363 if (btrfs_extent_refs(leaf, ei) !=
2364 btrfs_extent_data_ref_count(leaf, ref) ||
2365 btrfs_extent_data_ref_root(leaf, ref) !=
2366 root->root_key.objectid ||
2367 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2368 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2376 int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
2379 struct btrfs_path *path;
2382 path = btrfs_alloc_path();
2387 ret = check_committed_ref(root, path, objectid,
2389 if (ret && ret != -ENOENT)
2392 ret = check_delayed_ref(root, path, objectid, offset, bytenr);
2393 } while (ret == -EAGAIN);
2396 btrfs_free_path(path);
2397 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2402 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2403 struct btrfs_root *root,
2404 struct extent_buffer *buf,
2405 int full_backref, int inc)
2407 struct btrfs_fs_info *fs_info = root->fs_info;
2413 struct btrfs_key key;
2414 struct btrfs_file_extent_item *fi;
2415 struct btrfs_ref generic_ref = { 0 };
2416 bool for_reloc = btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC);
2422 if (btrfs_is_testing(fs_info))
2425 ref_root = btrfs_header_owner(buf);
2426 nritems = btrfs_header_nritems(buf);
2427 level = btrfs_header_level(buf);
2429 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state) && level == 0)
2433 parent = buf->start;
2437 action = BTRFS_ADD_DELAYED_REF;
2439 action = BTRFS_DROP_DELAYED_REF;
2441 for (i = 0; i < nritems; i++) {
2443 btrfs_item_key_to_cpu(buf, &key, i);
2444 if (key.type != BTRFS_EXTENT_DATA_KEY)
2446 fi = btrfs_item_ptr(buf, i,
2447 struct btrfs_file_extent_item);
2448 if (btrfs_file_extent_type(buf, fi) ==
2449 BTRFS_FILE_EXTENT_INLINE)
2451 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2455 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2456 key.offset -= btrfs_file_extent_offset(buf, fi);
2457 btrfs_init_generic_ref(&generic_ref, action, bytenr,
2459 generic_ref.real_root = root->root_key.objectid;
2460 btrfs_init_data_ref(&generic_ref, ref_root, key.objectid,
2462 generic_ref.skip_qgroup = for_reloc;
2464 ret = btrfs_inc_extent_ref(trans, &generic_ref);
2466 ret = btrfs_free_extent(trans, &generic_ref);
2470 bytenr = btrfs_node_blockptr(buf, i);
2471 num_bytes = fs_info->nodesize;
2472 btrfs_init_generic_ref(&generic_ref, action, bytenr,
2474 generic_ref.real_root = root->root_key.objectid;
2475 btrfs_init_tree_ref(&generic_ref, level - 1, ref_root);
2476 generic_ref.skip_qgroup = for_reloc;
2478 ret = btrfs_inc_extent_ref(trans, &generic_ref);
2480 ret = btrfs_free_extent(trans, &generic_ref);
2490 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2491 struct extent_buffer *buf, int full_backref)
2493 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2496 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2497 struct extent_buffer *buf, int full_backref)
2499 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2502 int btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr)
2504 struct btrfs_block_group *block_group;
2507 block_group = btrfs_lookup_block_group(fs_info, bytenr);
2508 if (!block_group || block_group->ro)
2511 btrfs_put_block_group(block_group);
2515 static u64 get_alloc_profile_by_root(struct btrfs_root *root, int data)
2517 struct btrfs_fs_info *fs_info = root->fs_info;
2522 flags = BTRFS_BLOCK_GROUP_DATA;
2523 else if (root == fs_info->chunk_root)
2524 flags = BTRFS_BLOCK_GROUP_SYSTEM;
2526 flags = BTRFS_BLOCK_GROUP_METADATA;
2528 ret = btrfs_get_alloc_profile(fs_info, flags);
2532 static u64 first_logical_byte(struct btrfs_fs_info *fs_info, u64 search_start)
2534 struct btrfs_block_group *cache;
2537 spin_lock(&fs_info->block_group_cache_lock);
2538 bytenr = fs_info->first_logical_byte;
2539 spin_unlock(&fs_info->block_group_cache_lock);
2541 if (bytenr < (u64)-1)
2544 cache = btrfs_lookup_first_block_group(fs_info, search_start);
2548 bytenr = cache->start;
2549 btrfs_put_block_group(cache);
2554 static int pin_down_extent(struct btrfs_trans_handle *trans,
2555 struct btrfs_block_group *cache,
2556 u64 bytenr, u64 num_bytes, int reserved)
2558 struct btrfs_fs_info *fs_info = cache->fs_info;
2560 spin_lock(&cache->space_info->lock);
2561 spin_lock(&cache->lock);
2562 cache->pinned += num_bytes;
2563 btrfs_space_info_update_bytes_pinned(fs_info, cache->space_info,
2566 cache->reserved -= num_bytes;
2567 cache->space_info->bytes_reserved -= num_bytes;
2569 spin_unlock(&cache->lock);
2570 spin_unlock(&cache->space_info->lock);
2572 percpu_counter_add_batch(&cache->space_info->total_bytes_pinned,
2573 num_bytes, BTRFS_TOTAL_BYTES_PINNED_BATCH);
2574 set_extent_dirty(&trans->transaction->pinned_extents, bytenr,
2575 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
2579 int btrfs_pin_extent(struct btrfs_trans_handle *trans,
2580 u64 bytenr, u64 num_bytes, int reserved)
2582 struct btrfs_block_group *cache;
2584 cache = btrfs_lookup_block_group(trans->fs_info, bytenr);
2585 BUG_ON(!cache); /* Logic error */
2587 pin_down_extent(trans, cache, bytenr, num_bytes, reserved);
2589 btrfs_put_block_group(cache);
2594 * this function must be called within transaction
2596 int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans,
2597 u64 bytenr, u64 num_bytes)
2599 struct btrfs_block_group *cache;
2602 btrfs_add_excluded_extent(trans->fs_info, bytenr, num_bytes);
2604 cache = btrfs_lookup_block_group(trans->fs_info, bytenr);
2609 * pull in the free space cache (if any) so that our pin
2610 * removes the free space from the cache. We have load_only set
2611 * to one because the slow code to read in the free extents does check
2612 * the pinned extents.
2614 btrfs_cache_block_group(cache, 1);
2616 pin_down_extent(trans, cache, bytenr, num_bytes, 0);
2618 /* remove us from the free space cache (if we're there at all) */
2619 ret = btrfs_remove_free_space(cache, bytenr, num_bytes);
2620 btrfs_put_block_group(cache);
2624 static int __exclude_logged_extent(struct btrfs_fs_info *fs_info,
2625 u64 start, u64 num_bytes)
2628 struct btrfs_block_group *block_group;
2629 struct btrfs_caching_control *caching_ctl;
2631 block_group = btrfs_lookup_block_group(fs_info, start);
2635 btrfs_cache_block_group(block_group, 0);
2636 caching_ctl = btrfs_get_caching_control(block_group);
2640 BUG_ON(!btrfs_block_group_done(block_group));
2641 ret = btrfs_remove_free_space(block_group, start, num_bytes);
2643 mutex_lock(&caching_ctl->mutex);
2645 if (start >= caching_ctl->progress) {
2646 ret = btrfs_add_excluded_extent(fs_info, start,
2648 } else if (start + num_bytes <= caching_ctl->progress) {
2649 ret = btrfs_remove_free_space(block_group,
2652 num_bytes = caching_ctl->progress - start;
2653 ret = btrfs_remove_free_space(block_group,
2658 num_bytes = (start + num_bytes) -
2659 caching_ctl->progress;
2660 start = caching_ctl->progress;
2661 ret = btrfs_add_excluded_extent(fs_info, start,
2665 mutex_unlock(&caching_ctl->mutex);
2666 btrfs_put_caching_control(caching_ctl);
2668 btrfs_put_block_group(block_group);
2672 int btrfs_exclude_logged_extents(struct extent_buffer *eb)
2674 struct btrfs_fs_info *fs_info = eb->fs_info;
2675 struct btrfs_file_extent_item *item;
2676 struct btrfs_key key;
2681 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS))
2684 for (i = 0; i < btrfs_header_nritems(eb); i++) {
2685 btrfs_item_key_to_cpu(eb, &key, i);
2686 if (key.type != BTRFS_EXTENT_DATA_KEY)
2688 item = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
2689 found_type = btrfs_file_extent_type(eb, item);
2690 if (found_type == BTRFS_FILE_EXTENT_INLINE)
2692 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
2694 key.objectid = btrfs_file_extent_disk_bytenr(eb, item);
2695 key.offset = btrfs_file_extent_disk_num_bytes(eb, item);
2696 ret = __exclude_logged_extent(fs_info, key.objectid, key.offset);
2705 btrfs_inc_block_group_reservations(struct btrfs_block_group *bg)
2707 atomic_inc(&bg->reservations);
2710 void btrfs_prepare_extent_commit(struct btrfs_fs_info *fs_info)
2712 struct btrfs_caching_control *next;
2713 struct btrfs_caching_control *caching_ctl;
2714 struct btrfs_block_group *cache;
2716 down_write(&fs_info->commit_root_sem);
2718 list_for_each_entry_safe(caching_ctl, next,
2719 &fs_info->caching_block_groups, list) {
2720 cache = caching_ctl->block_group;
2721 if (btrfs_block_group_done(cache)) {
2722 cache->last_byte_to_unpin = (u64)-1;
2723 list_del_init(&caching_ctl->list);
2724 btrfs_put_caching_control(caching_ctl);
2726 cache->last_byte_to_unpin = caching_ctl->progress;
2730 up_write(&fs_info->commit_root_sem);
2732 btrfs_update_global_block_rsv(fs_info);
2736 * Returns the free cluster for the given space info and sets empty_cluster to
2737 * what it should be based on the mount options.
2739 static struct btrfs_free_cluster *
2740 fetch_cluster_info(struct btrfs_fs_info *fs_info,
2741 struct btrfs_space_info *space_info, u64 *empty_cluster)
2743 struct btrfs_free_cluster *ret = NULL;
2746 if (btrfs_mixed_space_info(space_info))
2749 if (space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
2750 ret = &fs_info->meta_alloc_cluster;
2751 if (btrfs_test_opt(fs_info, SSD))
2752 *empty_cluster = SZ_2M;
2754 *empty_cluster = SZ_64K;
2755 } else if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) &&
2756 btrfs_test_opt(fs_info, SSD_SPREAD)) {
2757 *empty_cluster = SZ_2M;
2758 ret = &fs_info->data_alloc_cluster;
2764 static int unpin_extent_range(struct btrfs_fs_info *fs_info,
2766 const bool return_free_space)
2768 struct btrfs_block_group *cache = NULL;
2769 struct btrfs_space_info *space_info;
2770 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
2771 struct btrfs_free_cluster *cluster = NULL;
2773 u64 total_unpinned = 0;
2774 u64 empty_cluster = 0;
2777 while (start <= end) {
2780 start >= cache->start + cache->length) {
2782 btrfs_put_block_group(cache);
2784 cache = btrfs_lookup_block_group(fs_info, start);
2785 BUG_ON(!cache); /* Logic error */
2787 cluster = fetch_cluster_info(fs_info,
2790 empty_cluster <<= 1;
2793 len = cache->start + cache->length - start;
2794 len = min(len, end + 1 - start);
2796 if (start < cache->last_byte_to_unpin) {
2797 len = min(len, cache->last_byte_to_unpin - start);
2798 if (return_free_space)
2799 btrfs_add_free_space(cache, start, len);
2803 total_unpinned += len;
2804 space_info = cache->space_info;
2807 * If this space cluster has been marked as fragmented and we've
2808 * unpinned enough in this block group to potentially allow a
2809 * cluster to be created inside of it go ahead and clear the
2812 if (cluster && cluster->fragmented &&
2813 total_unpinned > empty_cluster) {
2814 spin_lock(&cluster->lock);
2815 cluster->fragmented = 0;
2816 spin_unlock(&cluster->lock);
2819 spin_lock(&space_info->lock);
2820 spin_lock(&cache->lock);
2821 cache->pinned -= len;
2822 btrfs_space_info_update_bytes_pinned(fs_info, space_info, -len);
2823 space_info->max_extent_size = 0;
2824 percpu_counter_add_batch(&space_info->total_bytes_pinned,
2825 -len, BTRFS_TOTAL_BYTES_PINNED_BATCH);
2827 space_info->bytes_readonly += len;
2830 spin_unlock(&cache->lock);
2831 if (!readonly && return_free_space &&
2832 global_rsv->space_info == space_info) {
2835 spin_lock(&global_rsv->lock);
2836 if (!global_rsv->full) {
2837 to_add = min(len, global_rsv->size -
2838 global_rsv->reserved);
2839 global_rsv->reserved += to_add;
2840 btrfs_space_info_update_bytes_may_use(fs_info,
2841 space_info, to_add);
2842 if (global_rsv->reserved >= global_rsv->size)
2843 global_rsv->full = 1;
2846 spin_unlock(&global_rsv->lock);
2847 /* Add to any tickets we may have */
2849 btrfs_try_granting_tickets(fs_info,
2852 spin_unlock(&space_info->lock);
2856 btrfs_put_block_group(cache);
2860 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans)
2862 struct btrfs_fs_info *fs_info = trans->fs_info;
2863 struct btrfs_block_group *block_group, *tmp;
2864 struct list_head *deleted_bgs;
2865 struct extent_io_tree *unpin;
2870 unpin = &trans->transaction->pinned_extents;
2872 while (!TRANS_ABORTED(trans)) {
2873 struct extent_state *cached_state = NULL;
2875 mutex_lock(&fs_info->unused_bg_unpin_mutex);
2876 ret = find_first_extent_bit(unpin, 0, &start, &end,
2877 EXTENT_DIRTY, &cached_state);
2879 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
2882 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
2883 clear_extent_bits(&fs_info->excluded_extents, start,
2884 end, EXTENT_UPTODATE);
2886 if (btrfs_test_opt(fs_info, DISCARD_SYNC))
2887 ret = btrfs_discard_extent(fs_info, start,
2888 end + 1 - start, NULL);
2890 clear_extent_dirty(unpin, start, end, &cached_state);
2891 unpin_extent_range(fs_info, start, end, true);
2892 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
2893 free_extent_state(cached_state);
2897 if (btrfs_test_opt(fs_info, DISCARD_ASYNC)) {
2898 btrfs_discard_calc_delay(&fs_info->discard_ctl);
2899 btrfs_discard_schedule_work(&fs_info->discard_ctl, true);
2903 * Transaction is finished. We don't need the lock anymore. We
2904 * do need to clean up the block groups in case of a transaction
2907 deleted_bgs = &trans->transaction->deleted_bgs;
2908 list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) {
2912 if (!TRANS_ABORTED(trans))
2913 ret = btrfs_discard_extent(fs_info,
2915 block_group->length,
2918 list_del_init(&block_group->bg_list);
2919 btrfs_unfreeze_block_group(block_group);
2920 btrfs_put_block_group(block_group);
2923 const char *errstr = btrfs_decode_error(ret);
2925 "discard failed while removing blockgroup: errno=%d %s",
2933 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
2934 struct btrfs_delayed_ref_node *node, u64 parent,
2935 u64 root_objectid, u64 owner_objectid,
2936 u64 owner_offset, int refs_to_drop,
2937 struct btrfs_delayed_extent_op *extent_op)
2939 struct btrfs_fs_info *info = trans->fs_info;
2940 struct btrfs_key key;
2941 struct btrfs_path *path;
2942 struct btrfs_root *extent_root = info->extent_root;
2943 struct extent_buffer *leaf;
2944 struct btrfs_extent_item *ei;
2945 struct btrfs_extent_inline_ref *iref;
2948 int extent_slot = 0;
2949 int found_extent = 0;
2953 u64 bytenr = node->bytenr;
2954 u64 num_bytes = node->num_bytes;
2956 bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA);
2958 path = btrfs_alloc_path();
2962 path->leave_spinning = 1;
2964 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
2965 BUG_ON(!is_data && refs_to_drop != 1);
2968 skinny_metadata = false;
2970 ret = lookup_extent_backref(trans, path, &iref, bytenr, num_bytes,
2971 parent, root_objectid, owner_objectid,
2974 extent_slot = path->slots[0];
2975 while (extent_slot >= 0) {
2976 btrfs_item_key_to_cpu(path->nodes[0], &key,
2978 if (key.objectid != bytenr)
2980 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
2981 key.offset == num_bytes) {
2985 if (key.type == BTRFS_METADATA_ITEM_KEY &&
2986 key.offset == owner_objectid) {
2990 if (path->slots[0] - extent_slot > 5)
2995 if (!found_extent) {
2997 ret = remove_extent_backref(trans, path, NULL,
2999 is_data, &last_ref);
3001 btrfs_abort_transaction(trans, ret);
3004 btrfs_release_path(path);
3005 path->leave_spinning = 1;
3007 key.objectid = bytenr;
3008 key.type = BTRFS_EXTENT_ITEM_KEY;
3009 key.offset = num_bytes;
3011 if (!is_data && skinny_metadata) {
3012 key.type = BTRFS_METADATA_ITEM_KEY;
3013 key.offset = owner_objectid;
3016 ret = btrfs_search_slot(trans, extent_root,
3018 if (ret > 0 && skinny_metadata && path->slots[0]) {
3020 * Couldn't find our skinny metadata item,
3021 * see if we have ye olde extent item.
3024 btrfs_item_key_to_cpu(path->nodes[0], &key,
3026 if (key.objectid == bytenr &&
3027 key.type == BTRFS_EXTENT_ITEM_KEY &&
3028 key.offset == num_bytes)
3032 if (ret > 0 && skinny_metadata) {
3033 skinny_metadata = false;
3034 key.objectid = bytenr;
3035 key.type = BTRFS_EXTENT_ITEM_KEY;
3036 key.offset = num_bytes;
3037 btrfs_release_path(path);
3038 ret = btrfs_search_slot(trans, extent_root,
3044 "umm, got %d back from search, was looking for %llu",
3047 btrfs_print_leaf(path->nodes[0]);
3050 btrfs_abort_transaction(trans, ret);
3053 extent_slot = path->slots[0];
3055 } else if (WARN_ON(ret == -ENOENT)) {
3056 btrfs_print_leaf(path->nodes[0]);
3058 "unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu",
3059 bytenr, parent, root_objectid, owner_objectid,
3061 btrfs_abort_transaction(trans, ret);
3064 btrfs_abort_transaction(trans, ret);
3068 leaf = path->nodes[0];
3069 item_size = btrfs_item_size_nr(leaf, extent_slot);
3070 if (unlikely(item_size < sizeof(*ei))) {
3072 btrfs_print_v0_err(info);
3073 btrfs_abort_transaction(trans, ret);
3076 ei = btrfs_item_ptr(leaf, extent_slot,
3077 struct btrfs_extent_item);
3078 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
3079 key.type == BTRFS_EXTENT_ITEM_KEY) {
3080 struct btrfs_tree_block_info *bi;
3081 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
3082 bi = (struct btrfs_tree_block_info *)(ei + 1);
3083 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
3086 refs = btrfs_extent_refs(leaf, ei);
3087 if (refs < refs_to_drop) {
3089 "trying to drop %d refs but we only have %Lu for bytenr %Lu",
3090 refs_to_drop, refs, bytenr);
3092 btrfs_abort_transaction(trans, ret);
3095 refs -= refs_to_drop;
3099 __run_delayed_extent_op(extent_op, leaf, ei);
3101 * In the case of inline back ref, reference count will
3102 * be updated by remove_extent_backref
3105 BUG_ON(!found_extent);
3107 btrfs_set_extent_refs(leaf, ei, refs);
3108 btrfs_mark_buffer_dirty(leaf);
3111 ret = remove_extent_backref(trans, path, iref,
3112 refs_to_drop, is_data,
3115 btrfs_abort_transaction(trans, ret);
3121 BUG_ON(is_data && refs_to_drop !=
3122 extent_data_ref_count(path, iref));
3124 BUG_ON(path->slots[0] != extent_slot);
3126 BUG_ON(path->slots[0] != extent_slot + 1);
3127 path->slots[0] = extent_slot;
3133 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
3136 btrfs_abort_transaction(trans, ret);
3139 btrfs_release_path(path);
3142 ret = btrfs_del_csums(trans, info->csum_root, bytenr,
3145 btrfs_abort_transaction(trans, ret);
3150 ret = add_to_free_space_tree(trans, bytenr, num_bytes);
3152 btrfs_abort_transaction(trans, ret);
3156 ret = btrfs_update_block_group(trans, bytenr, num_bytes, 0);
3158 btrfs_abort_transaction(trans, ret);
3162 btrfs_release_path(path);
3165 btrfs_free_path(path);
3170 * when we free an block, it is possible (and likely) that we free the last
3171 * delayed ref for that extent as well. This searches the delayed ref tree for
3172 * a given extent, and if there are no other delayed refs to be processed, it
3173 * removes it from the tree.
3175 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
3178 struct btrfs_delayed_ref_head *head;
3179 struct btrfs_delayed_ref_root *delayed_refs;
3182 delayed_refs = &trans->transaction->delayed_refs;
3183 spin_lock(&delayed_refs->lock);
3184 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
3186 goto out_delayed_unlock;
3188 spin_lock(&head->lock);
3189 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root))
3192 if (cleanup_extent_op(head) != NULL)
3196 * waiting for the lock here would deadlock. If someone else has it
3197 * locked they are already in the process of dropping it anyway
3199 if (!mutex_trylock(&head->mutex))
3202 btrfs_delete_ref_head(delayed_refs, head);
3203 head->processing = 0;
3205 spin_unlock(&head->lock);
3206 spin_unlock(&delayed_refs->lock);
3208 BUG_ON(head->extent_op);
3209 if (head->must_insert_reserved)
3212 btrfs_cleanup_ref_head_accounting(trans->fs_info, delayed_refs, head);
3213 mutex_unlock(&head->mutex);
3214 btrfs_put_delayed_ref_head(head);
3217 spin_unlock(&head->lock);
3220 spin_unlock(&delayed_refs->lock);
3224 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
3225 struct btrfs_root *root,
3226 struct extent_buffer *buf,
3227 u64 parent, int last_ref)
3229 struct btrfs_fs_info *fs_info = root->fs_info;
3230 struct btrfs_ref generic_ref = { 0 };
3234 btrfs_init_generic_ref(&generic_ref, BTRFS_DROP_DELAYED_REF,
3235 buf->start, buf->len, parent);
3236 btrfs_init_tree_ref(&generic_ref, btrfs_header_level(buf),
3237 root->root_key.objectid);
3239 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
3240 int old_ref_mod, new_ref_mod;
3242 btrfs_ref_tree_mod(fs_info, &generic_ref);
3243 ret = btrfs_add_delayed_tree_ref(trans, &generic_ref, NULL,
3244 &old_ref_mod, &new_ref_mod);
3245 BUG_ON(ret); /* -ENOMEM */
3246 pin = old_ref_mod >= 0 && new_ref_mod < 0;
3249 if (last_ref && btrfs_header_generation(buf) == trans->transid) {
3250 struct btrfs_block_group *cache;
3252 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
3253 ret = check_ref_cleanup(trans, buf->start);
3259 cache = btrfs_lookup_block_group(fs_info, buf->start);
3261 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
3262 pin_down_extent(trans, cache, buf->start, buf->len, 1);
3263 btrfs_put_block_group(cache);
3267 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
3269 btrfs_add_free_space(cache, buf->start, buf->len);
3270 btrfs_free_reserved_bytes(cache, buf->len, 0);
3271 btrfs_put_block_group(cache);
3272 trace_btrfs_reserved_extent_free(fs_info, buf->start, buf->len);
3276 add_pinned_bytes(fs_info, &generic_ref);
3280 * Deleting the buffer, clear the corrupt flag since it doesn't
3283 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
3287 /* Can return -ENOMEM */
3288 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_ref *ref)
3290 struct btrfs_fs_info *fs_info = trans->fs_info;
3291 int old_ref_mod, new_ref_mod;
3294 if (btrfs_is_testing(fs_info))
3298 * tree log blocks never actually go into the extent allocation
3299 * tree, just update pinning info and exit early.
3301 if ((ref->type == BTRFS_REF_METADATA &&
3302 ref->tree_ref.root == BTRFS_TREE_LOG_OBJECTID) ||
3303 (ref->type == BTRFS_REF_DATA &&
3304 ref->data_ref.ref_root == BTRFS_TREE_LOG_OBJECTID)) {
3305 /* unlocks the pinned mutex */
3306 btrfs_pin_extent(trans, ref->bytenr, ref->len, 1);
3307 old_ref_mod = new_ref_mod = 0;
3309 } else if (ref->type == BTRFS_REF_METADATA) {
3310 ret = btrfs_add_delayed_tree_ref(trans, ref, NULL,
3311 &old_ref_mod, &new_ref_mod);
3313 ret = btrfs_add_delayed_data_ref(trans, ref, 0,
3314 &old_ref_mod, &new_ref_mod);
3317 if (!((ref->type == BTRFS_REF_METADATA &&
3318 ref->tree_ref.root == BTRFS_TREE_LOG_OBJECTID) ||
3319 (ref->type == BTRFS_REF_DATA &&
3320 ref->data_ref.ref_root == BTRFS_TREE_LOG_OBJECTID)))
3321 btrfs_ref_tree_mod(fs_info, ref);
3323 if (ret == 0 && old_ref_mod >= 0 && new_ref_mod < 0)
3324 add_pinned_bytes(fs_info, ref);
3329 enum btrfs_loop_type {
3330 LOOP_CACHING_NOWAIT,
3337 btrfs_lock_block_group(struct btrfs_block_group *cache,
3341 down_read(&cache->data_rwsem);
3344 static inline void btrfs_grab_block_group(struct btrfs_block_group *cache,
3347 btrfs_get_block_group(cache);
3349 down_read(&cache->data_rwsem);
3352 static struct btrfs_block_group *btrfs_lock_cluster(
3353 struct btrfs_block_group *block_group,
3354 struct btrfs_free_cluster *cluster,
3356 __acquires(&cluster->refill_lock)
3358 struct btrfs_block_group *used_bg = NULL;
3360 spin_lock(&cluster->refill_lock);
3362 used_bg = cluster->block_group;
3366 if (used_bg == block_group)
3369 btrfs_get_block_group(used_bg);
3374 if (down_read_trylock(&used_bg->data_rwsem))
3377 spin_unlock(&cluster->refill_lock);
3379 /* We should only have one-level nested. */
3380 down_read_nested(&used_bg->data_rwsem, SINGLE_DEPTH_NESTING);
3382 spin_lock(&cluster->refill_lock);
3383 if (used_bg == cluster->block_group)
3386 up_read(&used_bg->data_rwsem);
3387 btrfs_put_block_group(used_bg);
3392 btrfs_release_block_group(struct btrfs_block_group *cache,
3396 up_read(&cache->data_rwsem);
3397 btrfs_put_block_group(cache);
3400 enum btrfs_extent_allocation_policy {
3401 BTRFS_EXTENT_ALLOC_CLUSTERED,
3405 * Structure used internally for find_free_extent() function. Wraps needed
3408 struct find_free_extent_ctl {
3409 /* Basic allocation info */
3415 /* Where to start the search inside the bg */
3418 /* For clustered allocation */
3420 struct btrfs_free_cluster *last_ptr;
3423 bool have_caching_bg;
3424 bool orig_have_caching_bg;
3426 /* RAID index, converted from flags */
3430 * Current loop number, check find_free_extent_update_loop() for details
3435 * Whether we're refilling a cluster, if true we need to re-search
3436 * current block group but don't try to refill the cluster again.
3438 bool retry_clustered;
3441 * Whether we're updating free space cache, if true we need to re-search
3442 * current block group but don't try updating free space cache again.
3444 bool retry_unclustered;
3446 /* If current block group is cached */
3449 /* Max contiguous hole found */
3450 u64 max_extent_size;
3452 /* Total free space from free space cache, not always contiguous */
3453 u64 total_free_space;
3458 /* Hint where to start looking for an empty space */
3461 /* Allocation policy */
3462 enum btrfs_extent_allocation_policy policy;
3467 * Helper function for find_free_extent().
3469 * Return -ENOENT to inform caller that we need fallback to unclustered mode.
3470 * Return -EAGAIN to inform caller that we need to re-search this block group
3471 * Return >0 to inform caller that we find nothing
3472 * Return 0 means we have found a location and set ffe_ctl->found_offset.
3474 static int find_free_extent_clustered(struct btrfs_block_group *bg,
3475 struct find_free_extent_ctl *ffe_ctl,
3476 struct btrfs_block_group **cluster_bg_ret)
3478 struct btrfs_block_group *cluster_bg;
3479 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
3480 u64 aligned_cluster;
3484 cluster_bg = btrfs_lock_cluster(bg, last_ptr, ffe_ctl->delalloc);
3486 goto refill_cluster;
3487 if (cluster_bg != bg && (cluster_bg->ro ||
3488 !block_group_bits(cluster_bg, ffe_ctl->flags)))
3489 goto release_cluster;
3491 offset = btrfs_alloc_from_cluster(cluster_bg, last_ptr,
3492 ffe_ctl->num_bytes, cluster_bg->start,
3493 &ffe_ctl->max_extent_size);
3495 /* We have a block, we're done */
3496 spin_unlock(&last_ptr->refill_lock);
3497 trace_btrfs_reserve_extent_cluster(cluster_bg,
3498 ffe_ctl->search_start, ffe_ctl->num_bytes);
3499 *cluster_bg_ret = cluster_bg;
3500 ffe_ctl->found_offset = offset;
3503 WARN_ON(last_ptr->block_group != cluster_bg);
3507 * If we are on LOOP_NO_EMPTY_SIZE, we can't set up a new clusters, so
3508 * lets just skip it and let the allocator find whatever block it can
3509 * find. If we reach this point, we will have tried the cluster
3510 * allocator plenty of times and not have found anything, so we are
3511 * likely way too fragmented for the clustering stuff to find anything.
3513 * However, if the cluster is taken from the current block group,
3514 * release the cluster first, so that we stand a better chance of
3515 * succeeding in the unclustered allocation.
3517 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE && cluster_bg != bg) {
3518 spin_unlock(&last_ptr->refill_lock);
3519 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
3523 /* This cluster didn't work out, free it and start over */
3524 btrfs_return_cluster_to_free_space(NULL, last_ptr);
3526 if (cluster_bg != bg)
3527 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
3530 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE) {
3531 spin_unlock(&last_ptr->refill_lock);
3535 aligned_cluster = max_t(u64,
3536 ffe_ctl->empty_cluster + ffe_ctl->empty_size,
3537 bg->full_stripe_len);
3538 ret = btrfs_find_space_cluster(bg, last_ptr, ffe_ctl->search_start,
3539 ffe_ctl->num_bytes, aligned_cluster);
3541 /* Now pull our allocation out of this cluster */
3542 offset = btrfs_alloc_from_cluster(bg, last_ptr,
3543 ffe_ctl->num_bytes, ffe_ctl->search_start,
3544 &ffe_ctl->max_extent_size);
3546 /* We found one, proceed */
3547 spin_unlock(&last_ptr->refill_lock);
3548 trace_btrfs_reserve_extent_cluster(bg,
3549 ffe_ctl->search_start,
3550 ffe_ctl->num_bytes);
3551 ffe_ctl->found_offset = offset;
3554 } else if (!ffe_ctl->cached && ffe_ctl->loop > LOOP_CACHING_NOWAIT &&
3555 !ffe_ctl->retry_clustered) {
3556 spin_unlock(&last_ptr->refill_lock);
3558 ffe_ctl->retry_clustered = true;
3559 btrfs_wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
3560 ffe_ctl->empty_cluster + ffe_ctl->empty_size);
3564 * At this point we either didn't find a cluster or we weren't able to
3565 * allocate a block from our cluster. Free the cluster we've been
3566 * trying to use, and go to the next block group.
3568 btrfs_return_cluster_to_free_space(NULL, last_ptr);
3569 spin_unlock(&last_ptr->refill_lock);
3574 * Return >0 to inform caller that we find nothing
3575 * Return 0 when we found an free extent and set ffe_ctrl->found_offset
3576 * Return -EAGAIN to inform caller that we need to re-search this block group
3578 static int find_free_extent_unclustered(struct btrfs_block_group *bg,
3579 struct find_free_extent_ctl *ffe_ctl)
3581 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
3585 * We are doing an unclustered allocation, set the fragmented flag so
3586 * we don't bother trying to setup a cluster again until we get more
3589 if (unlikely(last_ptr)) {
3590 spin_lock(&last_ptr->lock);
3591 last_ptr->fragmented = 1;
3592 spin_unlock(&last_ptr->lock);
3594 if (ffe_ctl->cached) {
3595 struct btrfs_free_space_ctl *free_space_ctl;
3597 free_space_ctl = bg->free_space_ctl;
3598 spin_lock(&free_space_ctl->tree_lock);
3599 if (free_space_ctl->free_space <
3600 ffe_ctl->num_bytes + ffe_ctl->empty_cluster +
3601 ffe_ctl->empty_size) {
3602 ffe_ctl->total_free_space = max_t(u64,
3603 ffe_ctl->total_free_space,
3604 free_space_ctl->free_space);
3605 spin_unlock(&free_space_ctl->tree_lock);
3608 spin_unlock(&free_space_ctl->tree_lock);
3611 offset = btrfs_find_space_for_alloc(bg, ffe_ctl->search_start,
3612 ffe_ctl->num_bytes, ffe_ctl->empty_size,
3613 &ffe_ctl->max_extent_size);
3616 * If we didn't find a chunk, and we haven't failed on this block group
3617 * before, and this block group is in the middle of caching and we are
3618 * ok with waiting, then go ahead and wait for progress to be made, and
3619 * set @retry_unclustered to true.
3621 * If @retry_unclustered is true then we've already waited on this
3622 * block group once and should move on to the next block group.
3624 if (!offset && !ffe_ctl->retry_unclustered && !ffe_ctl->cached &&
3625 ffe_ctl->loop > LOOP_CACHING_NOWAIT) {
3626 btrfs_wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
3627 ffe_ctl->empty_size);
3628 ffe_ctl->retry_unclustered = true;
3630 } else if (!offset) {
3633 ffe_ctl->found_offset = offset;
3637 static int do_allocation_clustered(struct btrfs_block_group *block_group,
3638 struct find_free_extent_ctl *ffe_ctl,
3639 struct btrfs_block_group **bg_ret)
3643 /* We want to try and use the cluster allocator, so lets look there */
3644 if (ffe_ctl->last_ptr && ffe_ctl->use_cluster) {
3645 ret = find_free_extent_clustered(block_group, ffe_ctl, bg_ret);
3646 if (ret >= 0 || ret == -EAGAIN)
3648 /* ret == -ENOENT case falls through */
3651 return find_free_extent_unclustered(block_group, ffe_ctl);
3654 static int do_allocation(struct btrfs_block_group *block_group,
3655 struct find_free_extent_ctl *ffe_ctl,
3656 struct btrfs_block_group **bg_ret)
3658 switch (ffe_ctl->policy) {
3659 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3660 return do_allocation_clustered(block_group, ffe_ctl, bg_ret);
3666 static void release_block_group(struct btrfs_block_group *block_group,
3667 struct find_free_extent_ctl *ffe_ctl,
3670 switch (ffe_ctl->policy) {
3671 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3672 ffe_ctl->retry_clustered = false;
3673 ffe_ctl->retry_unclustered = false;
3679 BUG_ON(btrfs_bg_flags_to_raid_index(block_group->flags) !=
3681 btrfs_release_block_group(block_group, delalloc);
3684 static void found_extent_clustered(struct find_free_extent_ctl *ffe_ctl,
3685 struct btrfs_key *ins)
3687 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
3689 if (!ffe_ctl->use_cluster && last_ptr) {
3690 spin_lock(&last_ptr->lock);
3691 last_ptr->window_start = ins->objectid;
3692 spin_unlock(&last_ptr->lock);
3696 static void found_extent(struct find_free_extent_ctl *ffe_ctl,
3697 struct btrfs_key *ins)
3699 switch (ffe_ctl->policy) {
3700 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3701 found_extent_clustered(ffe_ctl, ins);
3708 static int chunk_allocation_failed(struct find_free_extent_ctl *ffe_ctl)
3710 switch (ffe_ctl->policy) {
3711 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3713 * If we can't allocate a new chunk we've already looped through
3714 * at least once, move on to the NO_EMPTY_SIZE case.
3716 ffe_ctl->loop = LOOP_NO_EMPTY_SIZE;
3724 * Return >0 means caller needs to re-search for free extent
3725 * Return 0 means we have the needed free extent.
3726 * Return <0 means we failed to locate any free extent.
3728 static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info,
3729 struct btrfs_key *ins,
3730 struct find_free_extent_ctl *ffe_ctl,
3733 struct btrfs_root *root = fs_info->extent_root;
3736 if ((ffe_ctl->loop == LOOP_CACHING_NOWAIT) &&
3737 ffe_ctl->have_caching_bg && !ffe_ctl->orig_have_caching_bg)
3738 ffe_ctl->orig_have_caching_bg = true;
3740 if (!ins->objectid && ffe_ctl->loop >= LOOP_CACHING_WAIT &&
3741 ffe_ctl->have_caching_bg)
3744 if (!ins->objectid && ++(ffe_ctl->index) < BTRFS_NR_RAID_TYPES)
3747 if (ins->objectid) {
3748 found_extent(ffe_ctl, ins);
3753 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
3754 * caching kthreads as we move along
3755 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
3756 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
3757 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
3760 if (ffe_ctl->loop < LOOP_NO_EMPTY_SIZE) {
3762 if (ffe_ctl->loop == LOOP_CACHING_NOWAIT) {
3764 * We want to skip the LOOP_CACHING_WAIT step if we
3765 * don't have any uncached bgs and we've already done a
3766 * full search through.
3768 if (ffe_ctl->orig_have_caching_bg || !full_search)
3769 ffe_ctl->loop = LOOP_CACHING_WAIT;
3771 ffe_ctl->loop = LOOP_ALLOC_CHUNK;
3776 if (ffe_ctl->loop == LOOP_ALLOC_CHUNK) {
3777 struct btrfs_trans_handle *trans;
3780 trans = current->journal_info;
3784 trans = btrfs_join_transaction(root);
3786 if (IS_ERR(trans)) {
3787 ret = PTR_ERR(trans);
3791 ret = btrfs_chunk_alloc(trans, ffe_ctl->flags,
3794 /* Do not bail out on ENOSPC since we can do more. */
3796 ret = chunk_allocation_failed(ffe_ctl);
3798 btrfs_abort_transaction(trans, ret);
3802 btrfs_end_transaction(trans);
3807 if (ffe_ctl->loop == LOOP_NO_EMPTY_SIZE) {
3808 if (ffe_ctl->policy != BTRFS_EXTENT_ALLOC_CLUSTERED)
3812 * Don't loop again if we already have no empty_size and
3815 if (ffe_ctl->empty_size == 0 &&
3816 ffe_ctl->empty_cluster == 0)
3818 ffe_ctl->empty_size = 0;
3819 ffe_ctl->empty_cluster = 0;
3826 static int prepare_allocation_clustered(struct btrfs_fs_info *fs_info,
3827 struct find_free_extent_ctl *ffe_ctl,
3828 struct btrfs_space_info *space_info,
3829 struct btrfs_key *ins)
3832 * If our free space is heavily fragmented we may not be able to make
3833 * big contiguous allocations, so instead of doing the expensive search
3834 * for free space, simply return ENOSPC with our max_extent_size so we
3835 * can go ahead and search for a more manageable chunk.
3837 * If our max_extent_size is large enough for our allocation simply
3838 * disable clustering since we will likely not be able to find enough
3839 * space to create a cluster and induce latency trying.
3841 if (space_info->max_extent_size) {
3842 spin_lock(&space_info->lock);
3843 if (space_info->max_extent_size &&
3844 ffe_ctl->num_bytes > space_info->max_extent_size) {
3845 ins->offset = space_info->max_extent_size;
3846 spin_unlock(&space_info->lock);
3848 } else if (space_info->max_extent_size) {
3849 ffe_ctl->use_cluster = false;
3851 spin_unlock(&space_info->lock);
3854 ffe_ctl->last_ptr = fetch_cluster_info(fs_info, space_info,
3855 &ffe_ctl->empty_cluster);
3856 if (ffe_ctl->last_ptr) {
3857 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
3859 spin_lock(&last_ptr->lock);
3860 if (last_ptr->block_group)
3861 ffe_ctl->hint_byte = last_ptr->window_start;
3862 if (last_ptr->fragmented) {
3864 * We still set window_start so we can keep track of the
3865 * last place we found an allocation to try and save
3868 ffe_ctl->hint_byte = last_ptr->window_start;
3869 ffe_ctl->use_cluster = false;
3871 spin_unlock(&last_ptr->lock);
3877 static int prepare_allocation(struct btrfs_fs_info *fs_info,
3878 struct find_free_extent_ctl *ffe_ctl,
3879 struct btrfs_space_info *space_info,
3880 struct btrfs_key *ins)
3882 switch (ffe_ctl->policy) {
3883 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3884 return prepare_allocation_clustered(fs_info, ffe_ctl,
3892 * walks the btree of allocated extents and find a hole of a given size.
3893 * The key ins is changed to record the hole:
3894 * ins->objectid == start position
3895 * ins->flags = BTRFS_EXTENT_ITEM_KEY
3896 * ins->offset == the size of the hole.
3897 * Any available blocks before search_start are skipped.
3899 * If there is no suitable free space, we will record the max size of
3900 * the free space extent currently.
3902 * The overall logic and call chain:
3904 * find_free_extent()
3905 * |- Iterate through all block groups
3906 * | |- Get a valid block group
3907 * | |- Try to do clustered allocation in that block group
3908 * | |- Try to do unclustered allocation in that block group
3909 * | |- Check if the result is valid
3910 * | | |- If valid, then exit
3911 * | |- Jump to next block group
3913 * |- Push harder to find free extents
3914 * |- If not found, re-iterate all block groups
3916 static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
3917 u64 ram_bytes, u64 num_bytes, u64 empty_size,
3918 u64 hint_byte_orig, struct btrfs_key *ins,
3919 u64 flags, int delalloc)
3922 int cache_block_group_error = 0;
3923 struct btrfs_block_group *block_group = NULL;
3924 struct find_free_extent_ctl ffe_ctl = {0};
3925 struct btrfs_space_info *space_info;
3926 bool full_search = false;
3928 WARN_ON(num_bytes < fs_info->sectorsize);
3930 ffe_ctl.num_bytes = num_bytes;
3931 ffe_ctl.empty_size = empty_size;
3932 ffe_ctl.flags = flags;
3933 ffe_ctl.search_start = 0;
3934 ffe_ctl.delalloc = delalloc;
3935 ffe_ctl.index = btrfs_bg_flags_to_raid_index(flags);
3936 ffe_ctl.have_caching_bg = false;
3937 ffe_ctl.orig_have_caching_bg = false;
3938 ffe_ctl.found_offset = 0;
3939 ffe_ctl.hint_byte = hint_byte_orig;
3940 ffe_ctl.policy = BTRFS_EXTENT_ALLOC_CLUSTERED;
3942 /* For clustered allocation */
3943 ffe_ctl.retry_clustered = false;
3944 ffe_ctl.retry_unclustered = false;
3945 ffe_ctl.last_ptr = NULL;
3946 ffe_ctl.use_cluster = true;
3948 ins->type = BTRFS_EXTENT_ITEM_KEY;
3952 trace_find_free_extent(fs_info, num_bytes, empty_size, flags);
3954 space_info = btrfs_find_space_info(fs_info, flags);
3956 btrfs_err(fs_info, "No space info for %llu", flags);
3960 ret = prepare_allocation(fs_info, &ffe_ctl, space_info, ins);
3964 ffe_ctl.search_start = max(ffe_ctl.search_start,
3965 first_logical_byte(fs_info, 0));
3966 ffe_ctl.search_start = max(ffe_ctl.search_start, ffe_ctl.hint_byte);
3967 if (ffe_ctl.search_start == ffe_ctl.hint_byte) {
3968 block_group = btrfs_lookup_block_group(fs_info,
3969 ffe_ctl.search_start);
3971 * we don't want to use the block group if it doesn't match our
3972 * allocation bits, or if its not cached.
3974 * However if we are re-searching with an ideal block group
3975 * picked out then we don't care that the block group is cached.
3977 if (block_group && block_group_bits(block_group, flags) &&
3978 block_group->cached != BTRFS_CACHE_NO) {
3979 down_read(&space_info->groups_sem);
3980 if (list_empty(&block_group->list) ||
3983 * someone is removing this block group,
3984 * we can't jump into the have_block_group
3985 * target because our list pointers are not
3988 btrfs_put_block_group(block_group);
3989 up_read(&space_info->groups_sem);
3991 ffe_ctl.index = btrfs_bg_flags_to_raid_index(
3992 block_group->flags);
3993 btrfs_lock_block_group(block_group, delalloc);
3994 goto have_block_group;
3996 } else if (block_group) {
3997 btrfs_put_block_group(block_group);
4001 ffe_ctl.have_caching_bg = false;
4002 if (ffe_ctl.index == btrfs_bg_flags_to_raid_index(flags) ||
4005 down_read(&space_info->groups_sem);
4006 list_for_each_entry(block_group,
4007 &space_info->block_groups[ffe_ctl.index], list) {
4008 struct btrfs_block_group *bg_ret;
4010 /* If the block group is read-only, we can skip it entirely. */
4011 if (unlikely(block_group->ro))
4014 btrfs_grab_block_group(block_group, delalloc);
4015 ffe_ctl.search_start = block_group->start;
4018 * this can happen if we end up cycling through all the
4019 * raid types, but we want to make sure we only allocate
4020 * for the proper type.
4022 if (!block_group_bits(block_group, flags)) {
4023 u64 extra = BTRFS_BLOCK_GROUP_DUP |
4024 BTRFS_BLOCK_GROUP_RAID1_MASK |
4025 BTRFS_BLOCK_GROUP_RAID56_MASK |
4026 BTRFS_BLOCK_GROUP_RAID10;
4029 * if they asked for extra copies and this block group
4030 * doesn't provide them, bail. This does allow us to
4031 * fill raid0 from raid1.
4033 if ((flags & extra) && !(block_group->flags & extra))
4037 * This block group has different flags than we want.
4038 * It's possible that we have MIXED_GROUP flag but no
4039 * block group is mixed. Just skip such block group.
4041 btrfs_release_block_group(block_group, delalloc);
4046 ffe_ctl.cached = btrfs_block_group_done(block_group);
4047 if (unlikely(!ffe_ctl.cached)) {
4048 ffe_ctl.have_caching_bg = true;
4049 ret = btrfs_cache_block_group(block_group, 0);
4052 * If we get ENOMEM here or something else we want to
4053 * try other block groups, because it may not be fatal.
4054 * However if we can't find anything else we need to
4055 * save our return here so that we return the actual
4056 * error that caused problems, not ENOSPC.
4059 if (!cache_block_group_error)
4060 cache_block_group_error = ret;
4067 if (unlikely(block_group->cached == BTRFS_CACHE_ERROR))
4071 ret = do_allocation(block_group, &ffe_ctl, &bg_ret);
4073 if (bg_ret && bg_ret != block_group) {
4074 btrfs_release_block_group(block_group, delalloc);
4075 block_group = bg_ret;
4077 } else if (ret == -EAGAIN) {
4078 goto have_block_group;
4079 } else if (ret > 0) {
4084 ffe_ctl.search_start = round_up(ffe_ctl.found_offset,
4085 fs_info->stripesize);
4087 /* move on to the next group */
4088 if (ffe_ctl.search_start + num_bytes >
4089 block_group->start + block_group->length) {
4090 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
4095 if (ffe_ctl.found_offset < ffe_ctl.search_start)
4096 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
4097 ffe_ctl.search_start - ffe_ctl.found_offset);
4099 ret = btrfs_add_reserved_bytes(block_group, ram_bytes,
4100 num_bytes, delalloc);
4101 if (ret == -EAGAIN) {
4102 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
4106 btrfs_inc_block_group_reservations(block_group);
4108 /* we are all good, lets return */
4109 ins->objectid = ffe_ctl.search_start;
4110 ins->offset = num_bytes;
4112 trace_btrfs_reserve_extent(block_group, ffe_ctl.search_start,
4114 btrfs_release_block_group(block_group, delalloc);
4117 release_block_group(block_group, &ffe_ctl, delalloc);
4120 up_read(&space_info->groups_sem);
4122 ret = find_free_extent_update_loop(fs_info, ins, &ffe_ctl, full_search);
4126 if (ret == -ENOSPC && !cache_block_group_error) {
4128 * Use ffe_ctl->total_free_space as fallback if we can't find
4129 * any contiguous hole.
4131 if (!ffe_ctl.max_extent_size)
4132 ffe_ctl.max_extent_size = ffe_ctl.total_free_space;
4133 spin_lock(&space_info->lock);
4134 space_info->max_extent_size = ffe_ctl.max_extent_size;
4135 spin_unlock(&space_info->lock);
4136 ins->offset = ffe_ctl.max_extent_size;
4137 } else if (ret == -ENOSPC) {
4138 ret = cache_block_group_error;
4144 * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
4145 * hole that is at least as big as @num_bytes.
4147 * @root - The root that will contain this extent
4149 * @ram_bytes - The amount of space in ram that @num_bytes take. This
4150 * is used for accounting purposes. This value differs
4151 * from @num_bytes only in the case of compressed extents.
4153 * @num_bytes - Number of bytes to allocate on-disk.
4155 * @min_alloc_size - Indicates the minimum amount of space that the
4156 * allocator should try to satisfy. In some cases
4157 * @num_bytes may be larger than what is required and if
4158 * the filesystem is fragmented then allocation fails.
4159 * However, the presence of @min_alloc_size gives a
4160 * chance to try and satisfy the smaller allocation.
4162 * @empty_size - A hint that you plan on doing more COW. This is the
4163 * size in bytes the allocator should try to find free
4164 * next to the block it returns. This is just a hint and
4165 * may be ignored by the allocator.
4167 * @hint_byte - Hint to the allocator to start searching above the byte
4168 * address passed. It might be ignored.
4170 * @ins - This key is modified to record the found hole. It will
4171 * have the following values:
4172 * ins->objectid == start position
4173 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4174 * ins->offset == the size of the hole.
4176 * @is_data - Boolean flag indicating whether an extent is
4177 * allocated for data (true) or metadata (false)
4179 * @delalloc - Boolean flag indicating whether this allocation is for
4180 * delalloc or not. If 'true' data_rwsem of block groups
4181 * is going to be acquired.
4184 * Returns 0 when an allocation succeeded or < 0 when an error occurred. In
4185 * case -ENOSPC is returned then @ins->offset will contain the size of the
4186 * largest available hole the allocator managed to find.
4188 int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
4189 u64 num_bytes, u64 min_alloc_size,
4190 u64 empty_size, u64 hint_byte,
4191 struct btrfs_key *ins, int is_data, int delalloc)
4193 struct btrfs_fs_info *fs_info = root->fs_info;
4194 bool final_tried = num_bytes == min_alloc_size;
4198 flags = get_alloc_profile_by_root(root, is_data);
4200 WARN_ON(num_bytes < fs_info->sectorsize);
4201 ret = find_free_extent(fs_info, ram_bytes, num_bytes, empty_size,
4202 hint_byte, ins, flags, delalloc);
4203 if (!ret && !is_data) {
4204 btrfs_dec_block_group_reservations(fs_info, ins->objectid);
4205 } else if (ret == -ENOSPC) {
4206 if (!final_tried && ins->offset) {
4207 num_bytes = min(num_bytes >> 1, ins->offset);
4208 num_bytes = round_down(num_bytes,
4209 fs_info->sectorsize);
4210 num_bytes = max(num_bytes, min_alloc_size);
4211 ram_bytes = num_bytes;
4212 if (num_bytes == min_alloc_size)
4215 } else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
4216 struct btrfs_space_info *sinfo;
4218 sinfo = btrfs_find_space_info(fs_info, flags);
4220 "allocation failed flags %llu, wanted %llu",
4223 btrfs_dump_space_info(fs_info, sinfo,
4231 int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
4232 u64 start, u64 len, int delalloc)
4234 struct btrfs_block_group *cache;
4236 cache = btrfs_lookup_block_group(fs_info, start);
4238 btrfs_err(fs_info, "Unable to find block group for %llu",
4243 btrfs_add_free_space(cache, start, len);
4244 btrfs_free_reserved_bytes(cache, len, delalloc);
4245 trace_btrfs_reserved_extent_free(fs_info, start, len);
4247 btrfs_put_block_group(cache);
4251 int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans, u64 start,
4254 struct btrfs_block_group *cache;
4257 cache = btrfs_lookup_block_group(trans->fs_info, start);
4259 btrfs_err(trans->fs_info, "unable to find block group for %llu",
4264 ret = pin_down_extent(trans, cache, start, len, 1);
4265 btrfs_put_block_group(cache);
4269 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4270 u64 parent, u64 root_objectid,
4271 u64 flags, u64 owner, u64 offset,
4272 struct btrfs_key *ins, int ref_mod)
4274 struct btrfs_fs_info *fs_info = trans->fs_info;
4276 struct btrfs_extent_item *extent_item;
4277 struct btrfs_extent_inline_ref *iref;
4278 struct btrfs_path *path;
4279 struct extent_buffer *leaf;
4284 type = BTRFS_SHARED_DATA_REF_KEY;
4286 type = BTRFS_EXTENT_DATA_REF_KEY;
4288 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
4290 path = btrfs_alloc_path();
4294 path->leave_spinning = 1;
4295 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
4298 btrfs_free_path(path);
4302 leaf = path->nodes[0];
4303 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4304 struct btrfs_extent_item);
4305 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
4306 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4307 btrfs_set_extent_flags(leaf, extent_item,
4308 flags | BTRFS_EXTENT_FLAG_DATA);
4310 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
4311 btrfs_set_extent_inline_ref_type(leaf, iref, type);
4313 struct btrfs_shared_data_ref *ref;
4314 ref = (struct btrfs_shared_data_ref *)(iref + 1);
4315 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
4316 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
4318 struct btrfs_extent_data_ref *ref;
4319 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
4320 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
4321 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
4322 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
4323 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
4326 btrfs_mark_buffer_dirty(path->nodes[0]);
4327 btrfs_free_path(path);
4329 ret = remove_from_free_space_tree(trans, ins->objectid, ins->offset);
4333 ret = btrfs_update_block_group(trans, ins->objectid, ins->offset, 1);
4334 if (ret) { /* -ENOENT, logic error */
4335 btrfs_err(fs_info, "update block group failed for %llu %llu",
4336 ins->objectid, ins->offset);
4339 trace_btrfs_reserved_extent_alloc(fs_info, ins->objectid, ins->offset);
4343 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
4344 struct btrfs_delayed_ref_node *node,
4345 struct btrfs_delayed_extent_op *extent_op)
4347 struct btrfs_fs_info *fs_info = trans->fs_info;
4349 struct btrfs_extent_item *extent_item;
4350 struct btrfs_key extent_key;
4351 struct btrfs_tree_block_info *block_info;
4352 struct btrfs_extent_inline_ref *iref;
4353 struct btrfs_path *path;
4354 struct extent_buffer *leaf;
4355 struct btrfs_delayed_tree_ref *ref;
4356 u32 size = sizeof(*extent_item) + sizeof(*iref);
4358 u64 flags = extent_op->flags_to_set;
4359 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
4361 ref = btrfs_delayed_node_to_tree_ref(node);
4363 extent_key.objectid = node->bytenr;
4364 if (skinny_metadata) {
4365 extent_key.offset = ref->level;
4366 extent_key.type = BTRFS_METADATA_ITEM_KEY;
4367 num_bytes = fs_info->nodesize;
4369 extent_key.offset = node->num_bytes;
4370 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
4371 size += sizeof(*block_info);
4372 num_bytes = node->num_bytes;
4375 path = btrfs_alloc_path();
4379 path->leave_spinning = 1;
4380 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
4383 btrfs_free_path(path);
4387 leaf = path->nodes[0];
4388 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4389 struct btrfs_extent_item);
4390 btrfs_set_extent_refs(leaf, extent_item, 1);
4391 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4392 btrfs_set_extent_flags(leaf, extent_item,
4393 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
4395 if (skinny_metadata) {
4396 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
4398 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
4399 btrfs_set_tree_block_key(leaf, block_info, &extent_op->key);
4400 btrfs_set_tree_block_level(leaf, block_info, ref->level);
4401 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
4404 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) {
4405 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
4406 btrfs_set_extent_inline_ref_type(leaf, iref,
4407 BTRFS_SHARED_BLOCK_REF_KEY);
4408 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->parent);
4410 btrfs_set_extent_inline_ref_type(leaf, iref,
4411 BTRFS_TREE_BLOCK_REF_KEY);
4412 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->root);
4415 btrfs_mark_buffer_dirty(leaf);
4416 btrfs_free_path(path);
4418 ret = remove_from_free_space_tree(trans, extent_key.objectid,
4423 ret = btrfs_update_block_group(trans, extent_key.objectid,
4424 fs_info->nodesize, 1);
4425 if (ret) { /* -ENOENT, logic error */
4426 btrfs_err(fs_info, "update block group failed for %llu %llu",
4427 extent_key.objectid, extent_key.offset);
4431 trace_btrfs_reserved_extent_alloc(fs_info, extent_key.objectid,
4436 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4437 struct btrfs_root *root, u64 owner,
4438 u64 offset, u64 ram_bytes,
4439 struct btrfs_key *ins)
4441 struct btrfs_ref generic_ref = { 0 };
4444 BUG_ON(root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
4446 btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
4447 ins->objectid, ins->offset, 0);
4448 btrfs_init_data_ref(&generic_ref, root->root_key.objectid, owner, offset);
4449 btrfs_ref_tree_mod(root->fs_info, &generic_ref);
4450 ret = btrfs_add_delayed_data_ref(trans, &generic_ref,
4451 ram_bytes, NULL, NULL);
4456 * this is used by the tree logging recovery code. It records that
4457 * an extent has been allocated and makes sure to clear the free
4458 * space cache bits as well
4460 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
4461 u64 root_objectid, u64 owner, u64 offset,
4462 struct btrfs_key *ins)
4464 struct btrfs_fs_info *fs_info = trans->fs_info;
4466 struct btrfs_block_group *block_group;
4467 struct btrfs_space_info *space_info;
4470 * Mixed block groups will exclude before processing the log so we only
4471 * need to do the exclude dance if this fs isn't mixed.
4473 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
4474 ret = __exclude_logged_extent(fs_info, ins->objectid,
4480 block_group = btrfs_lookup_block_group(fs_info, ins->objectid);
4484 space_info = block_group->space_info;
4485 spin_lock(&space_info->lock);
4486 spin_lock(&block_group->lock);
4487 space_info->bytes_reserved += ins->offset;
4488 block_group->reserved += ins->offset;
4489 spin_unlock(&block_group->lock);
4490 spin_unlock(&space_info->lock);
4492 ret = alloc_reserved_file_extent(trans, 0, root_objectid, 0, owner,
4495 btrfs_pin_extent(trans, ins->objectid, ins->offset, 1);
4496 btrfs_put_block_group(block_group);
4500 static struct extent_buffer *
4501 btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
4502 u64 bytenr, int level, u64 owner)
4504 struct btrfs_fs_info *fs_info = root->fs_info;
4505 struct extent_buffer *buf;
4507 buf = btrfs_find_create_tree_block(fs_info, bytenr);
4512 * Extra safety check in case the extent tree is corrupted and extent
4513 * allocator chooses to use a tree block which is already used and
4516 if (buf->lock_owner == current->pid) {
4517 btrfs_err_rl(fs_info,
4518 "tree block %llu owner %llu already locked by pid=%d, extent tree corruption detected",
4519 buf->start, btrfs_header_owner(buf), current->pid);
4520 free_extent_buffer(buf);
4521 return ERR_PTR(-EUCLEAN);
4524 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
4525 btrfs_tree_lock(buf);
4526 btrfs_clean_tree_block(buf);
4527 clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
4529 btrfs_set_lock_blocking_write(buf);
4530 set_extent_buffer_uptodate(buf);
4532 memzero_extent_buffer(buf, 0, sizeof(struct btrfs_header));
4533 btrfs_set_header_level(buf, level);
4534 btrfs_set_header_bytenr(buf, buf->start);
4535 btrfs_set_header_generation(buf, trans->transid);
4536 btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV);
4537 btrfs_set_header_owner(buf, owner);
4538 write_extent_buffer_fsid(buf, fs_info->fs_devices->metadata_uuid);
4539 write_extent_buffer_chunk_tree_uuid(buf, fs_info->chunk_tree_uuid);
4540 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
4541 buf->log_index = root->log_transid % 2;
4543 * we allow two log transactions at a time, use different
4544 * EXTENT bit to differentiate dirty pages.
4546 if (buf->log_index == 0)
4547 set_extent_dirty(&root->dirty_log_pages, buf->start,
4548 buf->start + buf->len - 1, GFP_NOFS);
4550 set_extent_new(&root->dirty_log_pages, buf->start,
4551 buf->start + buf->len - 1);
4553 buf->log_index = -1;
4554 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
4555 buf->start + buf->len - 1, GFP_NOFS);
4557 trans->dirty = true;
4558 /* this returns a buffer locked for blocking */
4563 * finds a free extent and does all the dirty work required for allocation
4564 * returns the tree buffer or an ERR_PTR on error.
4566 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
4567 struct btrfs_root *root,
4568 u64 parent, u64 root_objectid,
4569 const struct btrfs_disk_key *key,
4570 int level, u64 hint,
4573 struct btrfs_fs_info *fs_info = root->fs_info;
4574 struct btrfs_key ins;
4575 struct btrfs_block_rsv *block_rsv;
4576 struct extent_buffer *buf;
4577 struct btrfs_delayed_extent_op *extent_op;
4578 struct btrfs_ref generic_ref = { 0 };
4581 u32 blocksize = fs_info->nodesize;
4582 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
4584 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4585 if (btrfs_is_testing(fs_info)) {
4586 buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr,
4587 level, root_objectid);
4589 root->alloc_bytenr += blocksize;
4594 block_rsv = btrfs_use_block_rsv(trans, root, blocksize);
4595 if (IS_ERR(block_rsv))
4596 return ERR_CAST(block_rsv);
4598 ret = btrfs_reserve_extent(root, blocksize, blocksize, blocksize,
4599 empty_size, hint, &ins, 0, 0);
4603 buf = btrfs_init_new_buffer(trans, root, ins.objectid, level,
4607 goto out_free_reserved;
4610 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
4612 parent = ins.objectid;
4613 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
4617 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
4618 extent_op = btrfs_alloc_delayed_extent_op();
4624 memcpy(&extent_op->key, key, sizeof(extent_op->key));
4626 memset(&extent_op->key, 0, sizeof(extent_op->key));
4627 extent_op->flags_to_set = flags;
4628 extent_op->update_key = skinny_metadata ? false : true;
4629 extent_op->update_flags = true;
4630 extent_op->is_data = false;
4631 extent_op->level = level;
4633 btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
4634 ins.objectid, ins.offset, parent);
4635 generic_ref.real_root = root->root_key.objectid;
4636 btrfs_init_tree_ref(&generic_ref, level, root_objectid);
4637 btrfs_ref_tree_mod(fs_info, &generic_ref);
4638 ret = btrfs_add_delayed_tree_ref(trans, &generic_ref,
4639 extent_op, NULL, NULL);
4641 goto out_free_delayed;
4646 btrfs_free_delayed_extent_op(extent_op);
4648 free_extent_buffer(buf);
4650 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0);
4652 btrfs_unuse_block_rsv(fs_info, block_rsv, blocksize);
4653 return ERR_PTR(ret);
4656 struct walk_control {
4657 u64 refs[BTRFS_MAX_LEVEL];
4658 u64 flags[BTRFS_MAX_LEVEL];
4659 struct btrfs_key update_progress;
4660 struct btrfs_key drop_progress;
4672 #define DROP_REFERENCE 1
4673 #define UPDATE_BACKREF 2
4675 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
4676 struct btrfs_root *root,
4677 struct walk_control *wc,
4678 struct btrfs_path *path)
4680 struct btrfs_fs_info *fs_info = root->fs_info;
4686 struct btrfs_key key;
4687 struct extent_buffer *eb;
4692 if (path->slots[wc->level] < wc->reada_slot) {
4693 wc->reada_count = wc->reada_count * 2 / 3;
4694 wc->reada_count = max(wc->reada_count, 2);
4696 wc->reada_count = wc->reada_count * 3 / 2;
4697 wc->reada_count = min_t(int, wc->reada_count,
4698 BTRFS_NODEPTRS_PER_BLOCK(fs_info));
4701 eb = path->nodes[wc->level];
4702 nritems = btrfs_header_nritems(eb);
4704 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
4705 if (nread >= wc->reada_count)
4709 bytenr = btrfs_node_blockptr(eb, slot);
4710 generation = btrfs_node_ptr_generation(eb, slot);
4712 if (slot == path->slots[wc->level])
4715 if (wc->stage == UPDATE_BACKREF &&
4716 generation <= root->root_key.offset)
4719 /* We don't lock the tree block, it's OK to be racy here */
4720 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr,
4721 wc->level - 1, 1, &refs,
4723 /* We don't care about errors in readahead. */
4728 if (wc->stage == DROP_REFERENCE) {
4732 if (wc->level == 1 &&
4733 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
4735 if (!wc->update_ref ||
4736 generation <= root->root_key.offset)
4738 btrfs_node_key_to_cpu(eb, &key, slot);
4739 ret = btrfs_comp_cpu_keys(&key,
4740 &wc->update_progress);
4744 if (wc->level == 1 &&
4745 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
4749 readahead_tree_block(fs_info, bytenr);
4752 wc->reada_slot = slot;
4756 * helper to process tree block while walking down the tree.
4758 * when wc->stage == UPDATE_BACKREF, this function updates
4759 * back refs for pointers in the block.
4761 * NOTE: return value 1 means we should stop walking down.
4763 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
4764 struct btrfs_root *root,
4765 struct btrfs_path *path,
4766 struct walk_control *wc, int lookup_info)
4768 struct btrfs_fs_info *fs_info = root->fs_info;
4769 int level = wc->level;
4770 struct extent_buffer *eb = path->nodes[level];
4771 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
4774 if (wc->stage == UPDATE_BACKREF &&
4775 btrfs_header_owner(eb) != root->root_key.objectid)
4779 * when reference count of tree block is 1, it won't increase
4780 * again. once full backref flag is set, we never clear it.
4783 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
4784 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
4785 BUG_ON(!path->locks[level]);
4786 ret = btrfs_lookup_extent_info(trans, fs_info,
4787 eb->start, level, 1,
4790 BUG_ON(ret == -ENOMEM);
4793 BUG_ON(wc->refs[level] == 0);
4796 if (wc->stage == DROP_REFERENCE) {
4797 if (wc->refs[level] > 1)
4800 if (path->locks[level] && !wc->keep_locks) {
4801 btrfs_tree_unlock_rw(eb, path->locks[level]);
4802 path->locks[level] = 0;
4807 /* wc->stage == UPDATE_BACKREF */
4808 if (!(wc->flags[level] & flag)) {
4809 BUG_ON(!path->locks[level]);
4810 ret = btrfs_inc_ref(trans, root, eb, 1);
4811 BUG_ON(ret); /* -ENOMEM */
4812 ret = btrfs_dec_ref(trans, root, eb, 0);
4813 BUG_ON(ret); /* -ENOMEM */
4814 ret = btrfs_set_disk_extent_flags(trans, eb, flag,
4815 btrfs_header_level(eb), 0);
4816 BUG_ON(ret); /* -ENOMEM */
4817 wc->flags[level] |= flag;
4821 * the block is shared by multiple trees, so it's not good to
4822 * keep the tree lock
4824 if (path->locks[level] && level > 0) {
4825 btrfs_tree_unlock_rw(eb, path->locks[level]);
4826 path->locks[level] = 0;
4832 * This is used to verify a ref exists for this root to deal with a bug where we
4833 * would have a drop_progress key that hadn't been updated properly.
4835 static int check_ref_exists(struct btrfs_trans_handle *trans,
4836 struct btrfs_root *root, u64 bytenr, u64 parent,
4839 struct btrfs_path *path;
4840 struct btrfs_extent_inline_ref *iref;
4843 path = btrfs_alloc_path();
4847 ret = lookup_extent_backref(trans, path, &iref, bytenr,
4848 root->fs_info->nodesize, parent,
4849 root->root_key.objectid, level, 0);
4850 btrfs_free_path(path);
4859 * helper to process tree block pointer.
4861 * when wc->stage == DROP_REFERENCE, this function checks
4862 * reference count of the block pointed to. if the block
4863 * is shared and we need update back refs for the subtree
4864 * rooted at the block, this function changes wc->stage to
4865 * UPDATE_BACKREF. if the block is shared and there is no
4866 * need to update back, this function drops the reference
4869 * NOTE: return value 1 means we should stop walking down.
4871 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
4872 struct btrfs_root *root,
4873 struct btrfs_path *path,
4874 struct walk_control *wc, int *lookup_info)
4876 struct btrfs_fs_info *fs_info = root->fs_info;
4880 struct btrfs_key key;
4881 struct btrfs_key first_key;
4882 struct btrfs_ref ref = { 0 };
4883 struct extent_buffer *next;
4884 int level = wc->level;
4887 bool need_account = false;
4889 generation = btrfs_node_ptr_generation(path->nodes[level],
4890 path->slots[level]);
4892 * if the lower level block was created before the snapshot
4893 * was created, we know there is no need to update back refs
4896 if (wc->stage == UPDATE_BACKREF &&
4897 generation <= root->root_key.offset) {
4902 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
4903 btrfs_node_key_to_cpu(path->nodes[level], &first_key,
4904 path->slots[level]);
4906 next = find_extent_buffer(fs_info, bytenr);
4908 next = btrfs_find_create_tree_block(fs_info, bytenr);
4910 return PTR_ERR(next);
4912 btrfs_set_buffer_lockdep_class(root->root_key.objectid, next,
4916 btrfs_tree_lock(next);
4917 btrfs_set_lock_blocking_write(next);
4919 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr, level - 1, 1,
4920 &wc->refs[level - 1],
4921 &wc->flags[level - 1]);
4925 if (unlikely(wc->refs[level - 1] == 0)) {
4926 btrfs_err(fs_info, "Missing references.");
4932 if (wc->stage == DROP_REFERENCE) {
4933 if (wc->refs[level - 1] > 1) {
4934 need_account = true;
4936 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
4939 if (!wc->update_ref ||
4940 generation <= root->root_key.offset)
4943 btrfs_node_key_to_cpu(path->nodes[level], &key,
4944 path->slots[level]);
4945 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
4949 wc->stage = UPDATE_BACKREF;
4950 wc->shared_level = level - 1;
4954 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
4958 if (!btrfs_buffer_uptodate(next, generation, 0)) {
4959 btrfs_tree_unlock(next);
4960 free_extent_buffer(next);
4966 if (reada && level == 1)
4967 reada_walk_down(trans, root, wc, path);
4968 next = read_tree_block(fs_info, bytenr, generation, level - 1,
4971 return PTR_ERR(next);
4972 } else if (!extent_buffer_uptodate(next)) {
4973 free_extent_buffer(next);
4976 btrfs_tree_lock(next);
4977 btrfs_set_lock_blocking_write(next);
4981 ASSERT(level == btrfs_header_level(next));
4982 if (level != btrfs_header_level(next)) {
4983 btrfs_err(root->fs_info, "mismatched level");
4987 path->nodes[level] = next;
4988 path->slots[level] = 0;
4989 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
4995 wc->refs[level - 1] = 0;
4996 wc->flags[level - 1] = 0;
4997 if (wc->stage == DROP_REFERENCE) {
4998 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
4999 parent = path->nodes[level]->start;
5001 ASSERT(root->root_key.objectid ==
5002 btrfs_header_owner(path->nodes[level]));
5003 if (root->root_key.objectid !=
5004 btrfs_header_owner(path->nodes[level])) {
5005 btrfs_err(root->fs_info,
5006 "mismatched block owner");
5014 * If we had a drop_progress we need to verify the refs are set
5015 * as expected. If we find our ref then we know that from here
5016 * on out everything should be correct, and we can clear the
5019 if (wc->restarted) {
5020 ret = check_ref_exists(trans, root, bytenr, parent,
5031 * Reloc tree doesn't contribute to qgroup numbers, and we have
5032 * already accounted them at merge time (replace_path),
5033 * thus we could skip expensive subtree trace here.
5035 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
5037 ret = btrfs_qgroup_trace_subtree(trans, next,
5038 generation, level - 1);
5040 btrfs_err_rl(fs_info,
5041 "Error %d accounting shared subtree. Quota is out of sync, rescan required.",
5047 * We need to update the next key in our walk control so we can
5048 * update the drop_progress key accordingly. We don't care if
5049 * find_next_key doesn't find a key because that means we're at
5050 * the end and are going to clean up now.
5052 wc->drop_level = level;
5053 find_next_key(path, level, &wc->drop_progress);
5055 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
5056 fs_info->nodesize, parent);
5057 btrfs_init_tree_ref(&ref, level - 1, root->root_key.objectid);
5058 ret = btrfs_free_extent(trans, &ref);
5067 btrfs_tree_unlock(next);
5068 free_extent_buffer(next);
5074 * helper to process tree block while walking up the tree.
5076 * when wc->stage == DROP_REFERENCE, this function drops
5077 * reference count on the block.
5079 * when wc->stage == UPDATE_BACKREF, this function changes
5080 * wc->stage back to DROP_REFERENCE if we changed wc->stage
5081 * to UPDATE_BACKREF previously while processing the block.
5083 * NOTE: return value 1 means we should stop walking up.
5085 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
5086 struct btrfs_root *root,
5087 struct btrfs_path *path,
5088 struct walk_control *wc)
5090 struct btrfs_fs_info *fs_info = root->fs_info;
5092 int level = wc->level;
5093 struct extent_buffer *eb = path->nodes[level];
5096 if (wc->stage == UPDATE_BACKREF) {
5097 BUG_ON(wc->shared_level < level);
5098 if (level < wc->shared_level)
5101 ret = find_next_key(path, level + 1, &wc->update_progress);
5105 wc->stage = DROP_REFERENCE;
5106 wc->shared_level = -1;
5107 path->slots[level] = 0;
5110 * check reference count again if the block isn't locked.
5111 * we should start walking down the tree again if reference
5114 if (!path->locks[level]) {
5116 btrfs_tree_lock(eb);
5117 btrfs_set_lock_blocking_write(eb);
5118 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
5120 ret = btrfs_lookup_extent_info(trans, fs_info,
5121 eb->start, level, 1,
5125 btrfs_tree_unlock_rw(eb, path->locks[level]);
5126 path->locks[level] = 0;
5129 BUG_ON(wc->refs[level] == 0);
5130 if (wc->refs[level] == 1) {
5131 btrfs_tree_unlock_rw(eb, path->locks[level]);
5132 path->locks[level] = 0;
5138 /* wc->stage == DROP_REFERENCE */
5139 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
5141 if (wc->refs[level] == 1) {
5143 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5144 ret = btrfs_dec_ref(trans, root, eb, 1);
5146 ret = btrfs_dec_ref(trans, root, eb, 0);
5147 BUG_ON(ret); /* -ENOMEM */
5148 if (is_fstree(root->root_key.objectid)) {
5149 ret = btrfs_qgroup_trace_leaf_items(trans, eb);
5151 btrfs_err_rl(fs_info,
5152 "error %d accounting leaf items, quota is out of sync, rescan required",
5157 /* make block locked assertion in btrfs_clean_tree_block happy */
5158 if (!path->locks[level] &&
5159 btrfs_header_generation(eb) == trans->transid) {
5160 btrfs_tree_lock(eb);
5161 btrfs_set_lock_blocking_write(eb);
5162 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
5164 btrfs_clean_tree_block(eb);
5167 if (eb == root->node) {
5168 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5170 else if (root->root_key.objectid != btrfs_header_owner(eb))
5171 goto owner_mismatch;
5173 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5174 parent = path->nodes[level + 1]->start;
5175 else if (root->root_key.objectid !=
5176 btrfs_header_owner(path->nodes[level + 1]))
5177 goto owner_mismatch;
5180 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
5182 wc->refs[level] = 0;
5183 wc->flags[level] = 0;
5187 btrfs_err_rl(fs_info, "unexpected tree owner, have %llu expect %llu",
5188 btrfs_header_owner(eb), root->root_key.objectid);
5192 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
5193 struct btrfs_root *root,
5194 struct btrfs_path *path,
5195 struct walk_control *wc)
5197 int level = wc->level;
5198 int lookup_info = 1;
5201 while (level >= 0) {
5202 ret = walk_down_proc(trans, root, path, wc, lookup_info);
5209 if (path->slots[level] >=
5210 btrfs_header_nritems(path->nodes[level]))
5213 ret = do_walk_down(trans, root, path, wc, &lookup_info);
5215 path->slots[level]++;
5224 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
5225 struct btrfs_root *root,
5226 struct btrfs_path *path,
5227 struct walk_control *wc, int max_level)
5229 int level = wc->level;
5232 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
5233 while (level < max_level && path->nodes[level]) {
5235 if (path->slots[level] + 1 <
5236 btrfs_header_nritems(path->nodes[level])) {
5237 path->slots[level]++;
5240 ret = walk_up_proc(trans, root, path, wc);
5246 if (path->locks[level]) {
5247 btrfs_tree_unlock_rw(path->nodes[level],
5248 path->locks[level]);
5249 path->locks[level] = 0;
5251 free_extent_buffer(path->nodes[level]);
5252 path->nodes[level] = NULL;
5260 * drop a subvolume tree.
5262 * this function traverses the tree freeing any blocks that only
5263 * referenced by the tree.
5265 * when a shared tree block is found. this function decreases its
5266 * reference count by one. if update_ref is true, this function
5267 * also make sure backrefs for the shared block and all lower level
5268 * blocks are properly updated.
5270 * If called with for_reloc == 0, may exit early with -EAGAIN
5272 int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
5274 struct btrfs_fs_info *fs_info = root->fs_info;
5275 struct btrfs_path *path;
5276 struct btrfs_trans_handle *trans;
5277 struct btrfs_root *tree_root = fs_info->tree_root;
5278 struct btrfs_root_item *root_item = &root->root_item;
5279 struct walk_control *wc;
5280 struct btrfs_key key;
5284 bool root_dropped = false;
5286 btrfs_debug(fs_info, "Drop subvolume %llu", root->root_key.objectid);
5288 path = btrfs_alloc_path();
5294 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5296 btrfs_free_path(path);
5301 trans = btrfs_start_transaction(tree_root, 0);
5302 if (IS_ERR(trans)) {
5303 err = PTR_ERR(trans);
5307 err = btrfs_run_delayed_items(trans);
5312 * This will help us catch people modifying the fs tree while we're
5313 * dropping it. It is unsafe to mess with the fs tree while it's being
5314 * dropped as we unlock the root node and parent nodes as we walk down
5315 * the tree, assuming nothing will change. If something does change
5316 * then we'll have stale information and drop references to blocks we've
5319 set_bit(BTRFS_ROOT_DELETING, &root->state);
5320 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
5321 level = btrfs_header_level(root->node);
5322 path->nodes[level] = btrfs_lock_root_node(root);
5323 btrfs_set_lock_blocking_write(path->nodes[level]);
5324 path->slots[level] = 0;
5325 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
5326 memset(&wc->update_progress, 0,
5327 sizeof(wc->update_progress));
5329 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
5330 memcpy(&wc->update_progress, &key,
5331 sizeof(wc->update_progress));
5333 level = root_item->drop_level;
5335 path->lowest_level = level;
5336 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5337 path->lowest_level = 0;
5345 * unlock our path, this is safe because only this
5346 * function is allowed to delete this snapshot
5348 btrfs_unlock_up_safe(path, 0);
5350 level = btrfs_header_level(root->node);
5352 btrfs_tree_lock(path->nodes[level]);
5353 btrfs_set_lock_blocking_write(path->nodes[level]);
5354 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
5356 ret = btrfs_lookup_extent_info(trans, fs_info,
5357 path->nodes[level]->start,
5358 level, 1, &wc->refs[level],
5364 BUG_ON(wc->refs[level] == 0);
5366 if (level == root_item->drop_level)
5369 btrfs_tree_unlock(path->nodes[level]);
5370 path->locks[level] = 0;
5371 WARN_ON(wc->refs[level] != 1);
5376 wc->restarted = test_bit(BTRFS_ROOT_DEAD_TREE, &root->state);
5378 wc->shared_level = -1;
5379 wc->stage = DROP_REFERENCE;
5380 wc->update_ref = update_ref;
5382 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
5386 ret = walk_down_tree(trans, root, path, wc);
5392 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
5399 BUG_ON(wc->stage != DROP_REFERENCE);
5403 if (wc->stage == DROP_REFERENCE) {
5404 wc->drop_level = wc->level;
5405 btrfs_node_key_to_cpu(path->nodes[wc->drop_level],
5407 path->slots[wc->drop_level]);
5409 btrfs_cpu_key_to_disk(&root_item->drop_progress,
5410 &wc->drop_progress);
5411 root_item->drop_level = wc->drop_level;
5413 BUG_ON(wc->level == 0);
5414 if (btrfs_should_end_transaction(trans) ||
5415 (!for_reloc && btrfs_need_cleaner_sleep(fs_info))) {
5416 ret = btrfs_update_root(trans, tree_root,
5420 btrfs_abort_transaction(trans, ret);
5425 btrfs_end_transaction_throttle(trans);
5426 if (!for_reloc && btrfs_need_cleaner_sleep(fs_info)) {
5427 btrfs_debug(fs_info,
5428 "drop snapshot early exit");
5433 trans = btrfs_start_transaction(tree_root, 0);
5434 if (IS_ERR(trans)) {
5435 err = PTR_ERR(trans);
5440 btrfs_release_path(path);
5444 ret = btrfs_del_root(trans, &root->root_key);
5446 btrfs_abort_transaction(trans, ret);
5451 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
5452 ret = btrfs_find_root(tree_root, &root->root_key, path,
5455 btrfs_abort_transaction(trans, ret);
5458 } else if (ret > 0) {
5459 /* if we fail to delete the orphan item this time
5460 * around, it'll get picked up the next time.
5462 * The most common failure here is just -ENOENT.
5464 btrfs_del_orphan_item(trans, tree_root,
5465 root->root_key.objectid);
5469 if (test_bit(BTRFS_ROOT_IN_RADIX, &root->state))
5470 btrfs_add_dropped_root(trans, root);
5472 btrfs_put_root(root);
5473 root_dropped = true;
5475 btrfs_end_transaction_throttle(trans);
5478 btrfs_free_path(path);
5481 * So if we need to stop dropping the snapshot for whatever reason we
5482 * need to make sure to add it back to the dead root list so that we
5483 * keep trying to do the work later. This also cleans up roots if we
5484 * don't have it in the radix (like when we recover after a power fail
5485 * or unmount) so we don't leak memory.
5487 if (!for_reloc && !root_dropped)
5488 btrfs_add_dead_root(root);
5493 * drop subtree rooted at tree block 'node'.
5495 * NOTE: this function will unlock and release tree block 'node'
5496 * only used by relocation code
5498 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
5499 struct btrfs_root *root,
5500 struct extent_buffer *node,
5501 struct extent_buffer *parent)
5503 struct btrfs_fs_info *fs_info = root->fs_info;
5504 struct btrfs_path *path;
5505 struct walk_control *wc;
5511 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
5513 path = btrfs_alloc_path();
5517 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5519 btrfs_free_path(path);
5523 btrfs_assert_tree_locked(parent);
5524 parent_level = btrfs_header_level(parent);
5525 atomic_inc(&parent->refs);
5526 path->nodes[parent_level] = parent;
5527 path->slots[parent_level] = btrfs_header_nritems(parent);
5529 btrfs_assert_tree_locked(node);
5530 level = btrfs_header_level(node);
5531 path->nodes[level] = node;
5532 path->slots[level] = 0;
5533 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
5535 wc->refs[parent_level] = 1;
5536 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5538 wc->shared_level = -1;
5539 wc->stage = DROP_REFERENCE;
5542 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
5545 wret = walk_down_tree(trans, root, path, wc);
5551 wret = walk_up_tree(trans, root, path, wc, parent_level);
5559 btrfs_free_path(path);
5564 * helper to account the unused space of all the readonly block group in the
5565 * space_info. takes mirrors into account.
5567 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
5569 struct btrfs_block_group *block_group;
5573 /* It's df, we don't care if it's racy */
5574 if (list_empty(&sinfo->ro_bgs))
5577 spin_lock(&sinfo->lock);
5578 list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) {
5579 spin_lock(&block_group->lock);
5581 if (!block_group->ro) {
5582 spin_unlock(&block_group->lock);
5586 factor = btrfs_bg_type_to_factor(block_group->flags);
5587 free_bytes += (block_group->length -
5588 block_group->used) * factor;
5590 spin_unlock(&block_group->lock);
5592 spin_unlock(&sinfo->lock);
5597 int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
5600 return unpin_extent_range(fs_info, start, end, false);
5604 * It used to be that old block groups would be left around forever.
5605 * Iterating over them would be enough to trim unused space. Since we
5606 * now automatically remove them, we also need to iterate over unallocated
5609 * We don't want a transaction for this since the discard may take a
5610 * substantial amount of time. We don't require that a transaction be
5611 * running, but we do need to take a running transaction into account
5612 * to ensure that we're not discarding chunks that were released or
5613 * allocated in the current transaction.
5615 * Holding the chunks lock will prevent other threads from allocating
5616 * or releasing chunks, but it won't prevent a running transaction
5617 * from committing and releasing the memory that the pending chunks
5618 * list head uses. For that, we need to take a reference to the
5619 * transaction and hold the commit root sem. We only need to hold
5620 * it while performing the free space search since we have already
5621 * held back allocations.
5623 static int btrfs_trim_free_extents(struct btrfs_device *device, u64 *trimmed)
5625 u64 start = SZ_1M, len = 0, end = 0;
5630 /* Discard not supported = nothing to do. */
5631 if (!blk_queue_discard(bdev_get_queue(device->bdev)))
5634 /* Not writable = nothing to do. */
5635 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
5638 /* No free space = nothing to do. */
5639 if (device->total_bytes <= device->bytes_used)
5645 struct btrfs_fs_info *fs_info = device->fs_info;
5648 ret = mutex_lock_interruptible(&fs_info->chunk_mutex);
5652 find_first_clear_extent_bit(&device->alloc_state, start,
5654 CHUNK_TRIMMED | CHUNK_ALLOCATED);
5656 /* Ensure we skip the reserved area in the first 1M */
5657 start = max_t(u64, start, SZ_1M);
5660 * If find_first_clear_extent_bit find a range that spans the
5661 * end of the device it will set end to -1, in this case it's up
5662 * to the caller to trim the value to the size of the device.
5664 end = min(end, device->total_bytes - 1);
5666 len = end - start + 1;
5668 /* We didn't find any extents */
5670 mutex_unlock(&fs_info->chunk_mutex);
5675 ret = btrfs_issue_discard(device->bdev, start, len,
5678 set_extent_bits(&device->alloc_state, start,
5681 mutex_unlock(&fs_info->chunk_mutex);
5689 if (fatal_signal_pending(current)) {
5701 * Trim the whole filesystem by:
5702 * 1) trimming the free space in each block group
5703 * 2) trimming the unallocated space on each device
5705 * This will also continue trimming even if a block group or device encounters
5706 * an error. The return value will be the last error, or 0 if nothing bad
5709 int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range)
5711 struct btrfs_block_group *cache = NULL;
5712 struct btrfs_device *device;
5713 struct list_head *devices;
5715 u64 range_end = U64_MAX;
5726 * Check range overflow if range->len is set.
5727 * The default range->len is U64_MAX.
5729 if (range->len != U64_MAX &&
5730 check_add_overflow(range->start, range->len, &range_end))
5733 cache = btrfs_lookup_first_block_group(fs_info, range->start);
5734 for (; cache; cache = btrfs_next_block_group(cache)) {
5735 if (cache->start >= range_end) {
5736 btrfs_put_block_group(cache);
5740 start = max(range->start, cache->start);
5741 end = min(range_end, cache->start + cache->length);
5743 if (end - start >= range->minlen) {
5744 if (!btrfs_block_group_done(cache)) {
5745 ret = btrfs_cache_block_group(cache, 0);
5751 ret = btrfs_wait_block_group_cache_done(cache);
5758 ret = btrfs_trim_block_group(cache,
5764 trimmed += group_trimmed;
5775 "failed to trim %llu block group(s), last error %d",
5777 mutex_lock(&fs_info->fs_devices->device_list_mutex);
5778 devices = &fs_info->fs_devices->devices;
5779 list_for_each_entry(device, devices, dev_list) {
5780 ret = btrfs_trim_free_extents(device, &group_trimmed);
5787 trimmed += group_trimmed;
5789 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
5793 "failed to trim %llu device(s), last error %d",
5794 dev_failed, dev_ret);
5795 range->len = trimmed;