2 * Copyright (C) 2011 STRATO. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
23 #include "transaction.h"
24 #include "delayed-ref.h"
27 struct extent_inode_elem
{
30 struct extent_inode_elem
*next
;
33 static int check_extent_in_eb(struct btrfs_key
*key
, struct extent_buffer
*eb
,
34 struct btrfs_file_extent_item
*fi
,
36 struct extent_inode_elem
**eie
)
40 struct extent_inode_elem
*e
;
42 data_offset
= btrfs_file_extent_offset(eb
, fi
);
43 data_len
= btrfs_file_extent_num_bytes(eb
, fi
);
45 if (extent_item_pos
< data_offset
||
46 extent_item_pos
>= data_offset
+ data_len
)
49 e
= kmalloc(sizeof(*e
), GFP_NOFS
);
54 e
->inum
= key
->objectid
;
55 e
->offset
= key
->offset
+ (extent_item_pos
- data_offset
);
61 static int find_extent_in_eb(struct extent_buffer
*eb
, u64 wanted_disk_byte
,
63 struct extent_inode_elem
**eie
)
67 struct btrfs_file_extent_item
*fi
;
74 * from the shared data ref, we only have the leaf but we need
75 * the key. thus, we must look into all items and see that we
76 * find one (some) with a reference to our extent item.
78 nritems
= btrfs_header_nritems(eb
);
79 for (slot
= 0; slot
< nritems
; ++slot
) {
80 btrfs_item_key_to_cpu(eb
, &key
, slot
);
81 if (key
.type
!= BTRFS_EXTENT_DATA_KEY
)
83 fi
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
84 extent_type
= btrfs_file_extent_type(eb
, fi
);
85 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
)
87 /* don't skip BTRFS_FILE_EXTENT_PREALLOC, we can handle that */
88 disk_byte
= btrfs_file_extent_disk_bytenr(eb
, fi
);
89 if (disk_byte
!= wanted_disk_byte
)
92 ret
= check_extent_in_eb(&key
, eb
, fi
, extent_item_pos
, eie
);
101 * this structure records all encountered refs on the way up to the root
103 struct __prelim_ref
{
104 struct list_head list
;
106 struct btrfs_key key_for_search
;
109 struct extent_inode_elem
*inode_list
;
111 u64 wanted_disk_byte
;
115 * the rules for all callers of this function are:
116 * - obtaining the parent is the goal
117 * - if you add a key, you must know that it is a correct key
118 * - if you cannot add the parent or a correct key, then we will look into the
119 * block later to set a correct key
123 * backref type | shared | indirect | shared | indirect
124 * information | tree | tree | data | data
125 * --------------------+--------+----------+--------+----------
126 * parent logical | y | - | - | -
127 * key to resolve | - | y | y | y
128 * tree block logical | - | - | - | -
129 * root for resolving | y | y | y | y
131 * - column 1: we've the parent -> done
132 * - column 2, 3, 4: we use the key to find the parent
134 * on disk refs (inline or keyed)
135 * ==============================
136 * backref type | shared | indirect | shared | indirect
137 * information | tree | tree | data | data
138 * --------------------+--------+----------+--------+----------
139 * parent logical | y | - | y | -
140 * key to resolve | - | - | - | y
141 * tree block logical | y | y | y | y
142 * root for resolving | - | y | y | y
144 * - column 1, 3: we've the parent -> done
145 * - column 2: we take the first key from the block to find the parent
146 * (see __add_missing_keys)
147 * - column 4: we use the key to find the parent
149 * additional information that's available but not required to find the parent
150 * block might help in merging entries to gain some speed.
153 static int __add_prelim_ref(struct list_head
*head
, u64 root_id
,
154 struct btrfs_key
*key
, int level
,
155 u64 parent
, u64 wanted_disk_byte
, int count
)
157 struct __prelim_ref
*ref
;
159 /* in case we're adding delayed refs, we're holding the refs spinlock */
160 ref
= kmalloc(sizeof(*ref
), GFP_ATOMIC
);
164 ref
->root_id
= root_id
;
166 ref
->key_for_search
= *key
;
168 memset(&ref
->key_for_search
, 0, sizeof(ref
->key_for_search
));
170 ref
->inode_list
= NULL
;
173 ref
->parent
= parent
;
174 ref
->wanted_disk_byte
= wanted_disk_byte
;
175 list_add_tail(&ref
->list
, head
);
180 static int add_all_parents(struct btrfs_root
*root
, struct btrfs_path
*path
,
181 struct ulist
*parents
, int level
,
182 struct btrfs_key
*key_for_search
, u64 time_seq
,
183 u64 wanted_disk_byte
,
184 const u64
*extent_item_pos
)
188 struct extent_buffer
*eb
;
189 struct btrfs_key key
;
190 struct btrfs_file_extent_item
*fi
;
191 struct extent_inode_elem
*eie
= NULL
;
195 eb
= path
->nodes
[level
];
196 ret
= ulist_add(parents
, eb
->start
, 0, GFP_NOFS
);
203 * We normally enter this function with the path already pointing to
204 * the first item to check. But sometimes, we may enter it with
205 * slot==nritems. In that case, go to the next leaf before we continue.
207 if (path
->slots
[0] >= btrfs_header_nritems(path
->nodes
[0]))
208 ret
= btrfs_next_old_leaf(root
, path
, time_seq
);
212 slot
= path
->slots
[0];
214 btrfs_item_key_to_cpu(eb
, &key
, slot
);
216 if (key
.objectid
!= key_for_search
->objectid
||
217 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
220 fi
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
221 disk_byte
= btrfs_file_extent_disk_bytenr(eb
, fi
);
223 if (disk_byte
== wanted_disk_byte
) {
225 if (extent_item_pos
) {
226 ret
= check_extent_in_eb(&key
, eb
, fi
,
233 ret
= ulist_add(parents
, eb
->start
,
234 (unsigned long)eie
, GFP_NOFS
);
237 if (!extent_item_pos
) {
238 ret
= btrfs_next_old_leaf(root
, path
,
244 ret
= btrfs_next_old_item(root
, path
, time_seq
);
253 * resolve an indirect backref in the form (root_id, key, level)
254 * to a logical address
256 static int __resolve_indirect_ref(struct btrfs_fs_info
*fs_info
,
257 int search_commit_root
,
259 struct __prelim_ref
*ref
,
260 struct ulist
*parents
,
261 const u64
*extent_item_pos
)
263 struct btrfs_path
*path
;
264 struct btrfs_root
*root
;
265 struct btrfs_key root_key
;
266 struct extent_buffer
*eb
;
269 int level
= ref
->level
;
271 path
= btrfs_alloc_path();
274 path
->search_commit_root
= !!search_commit_root
;
276 root_key
.objectid
= ref
->root_id
;
277 root_key
.type
= BTRFS_ROOT_ITEM_KEY
;
278 root_key
.offset
= (u64
)-1;
279 root
= btrfs_read_fs_root_no_name(fs_info
, &root_key
);
286 root_level
= btrfs_header_level(root
->node
);
289 if (root_level
+ 1 == level
)
292 path
->lowest_level
= level
;
293 ret
= btrfs_search_old_slot(root
, &ref
->key_for_search
, path
, time_seq
);
294 pr_debug("search slot in root %llu (level %d, ref count %d) returned "
295 "%d for key (%llu %u %llu)\n",
296 (unsigned long long)ref
->root_id
, level
, ref
->count
, ret
,
297 (unsigned long long)ref
->key_for_search
.objectid
,
298 ref
->key_for_search
.type
,
299 (unsigned long long)ref
->key_for_search
.offset
);
303 eb
= path
->nodes
[level
];
310 ret
= add_all_parents(root
, path
, parents
, level
, &ref
->key_for_search
,
311 time_seq
, ref
->wanted_disk_byte
,
314 btrfs_free_path(path
);
319 * resolve all indirect backrefs from the list
321 static int __resolve_indirect_refs(struct btrfs_fs_info
*fs_info
,
322 int search_commit_root
, u64 time_seq
,
323 struct list_head
*head
,
324 const u64
*extent_item_pos
)
328 struct __prelim_ref
*ref
;
329 struct __prelim_ref
*ref_safe
;
330 struct __prelim_ref
*new_ref
;
331 struct ulist
*parents
;
332 struct ulist_node
*node
;
333 struct ulist_iterator uiter
;
335 parents
= ulist_alloc(GFP_NOFS
);
340 * _safe allows us to insert directly after the current item without
341 * iterating over the newly inserted items.
342 * we're also allowed to re-assign ref during iteration.
344 list_for_each_entry_safe(ref
, ref_safe
, head
, list
) {
345 if (ref
->parent
) /* already direct */
349 err
= __resolve_indirect_ref(fs_info
, search_commit_root
,
350 time_seq
, ref
, parents
,
358 /* we put the first parent into the ref at hand */
359 ULIST_ITER_INIT(&uiter
);
360 node
= ulist_next(parents
, &uiter
);
361 ref
->parent
= node
? node
->val
: 0;
363 node
? (struct extent_inode_elem
*)node
->aux
: 0;
365 /* additional parents require new refs being added here */
366 while ((node
= ulist_next(parents
, &uiter
))) {
367 new_ref
= kmalloc(sizeof(*new_ref
), GFP_NOFS
);
372 memcpy(new_ref
, ref
, sizeof(*ref
));
373 new_ref
->parent
= node
->val
;
374 new_ref
->inode_list
=
375 (struct extent_inode_elem
*)node
->aux
;
376 list_add(&new_ref
->list
, &ref
->list
);
378 ulist_reinit(parents
);
385 static inline int ref_for_same_block(struct __prelim_ref
*ref1
,
386 struct __prelim_ref
*ref2
)
388 if (ref1
->level
!= ref2
->level
)
390 if (ref1
->root_id
!= ref2
->root_id
)
392 if (ref1
->key_for_search
.type
!= ref2
->key_for_search
.type
)
394 if (ref1
->key_for_search
.objectid
!= ref2
->key_for_search
.objectid
)
396 if (ref1
->key_for_search
.offset
!= ref2
->key_for_search
.offset
)
398 if (ref1
->parent
!= ref2
->parent
)
405 * read tree blocks and add keys where required.
407 static int __add_missing_keys(struct btrfs_fs_info
*fs_info
,
408 struct list_head
*head
)
410 struct list_head
*pos
;
411 struct extent_buffer
*eb
;
413 list_for_each(pos
, head
) {
414 struct __prelim_ref
*ref
;
415 ref
= list_entry(pos
, struct __prelim_ref
, list
);
419 if (ref
->key_for_search
.type
)
421 BUG_ON(!ref
->wanted_disk_byte
);
422 eb
= read_tree_block(fs_info
->tree_root
, ref
->wanted_disk_byte
,
423 fs_info
->tree_root
->leafsize
, 0);
425 btrfs_tree_read_lock(eb
);
426 if (btrfs_header_level(eb
) == 0)
427 btrfs_item_key_to_cpu(eb
, &ref
->key_for_search
, 0);
429 btrfs_node_key_to_cpu(eb
, &ref
->key_for_search
, 0);
430 btrfs_tree_read_unlock(eb
);
431 free_extent_buffer(eb
);
437 * merge two lists of backrefs and adjust counts accordingly
439 * mode = 1: merge identical keys, if key is set
440 * FIXME: if we add more keys in __add_prelim_ref, we can merge more here.
441 * additionally, we could even add a key range for the blocks we
442 * looked into to merge even more (-> replace unresolved refs by those
444 * mode = 2: merge identical parents
446 static int __merge_refs(struct list_head
*head
, int mode
)
448 struct list_head
*pos1
;
450 list_for_each(pos1
, head
) {
451 struct list_head
*n2
;
452 struct list_head
*pos2
;
453 struct __prelim_ref
*ref1
;
455 ref1
= list_entry(pos1
, struct __prelim_ref
, list
);
457 for (pos2
= pos1
->next
, n2
= pos2
->next
; pos2
!= head
;
458 pos2
= n2
, n2
= pos2
->next
) {
459 struct __prelim_ref
*ref2
;
460 struct __prelim_ref
*xchg
;
462 ref2
= list_entry(pos2
, struct __prelim_ref
, list
);
465 if (!ref_for_same_block(ref1
, ref2
))
467 if (!ref1
->parent
&& ref2
->parent
) {
472 ref1
->count
+= ref2
->count
;
474 if (ref1
->parent
!= ref2
->parent
)
476 ref1
->count
+= ref2
->count
;
478 list_del(&ref2
->list
);
487 * add all currently queued delayed refs from this head whose seq nr is
488 * smaller or equal that seq to the list
490 static int __add_delayed_refs(struct btrfs_delayed_ref_head
*head
, u64 seq
,
491 struct list_head
*prefs
)
493 struct btrfs_delayed_extent_op
*extent_op
= head
->extent_op
;
494 struct rb_node
*n
= &head
->node
.rb_node
;
495 struct btrfs_key key
;
496 struct btrfs_key op_key
= {0};
500 if (extent_op
&& extent_op
->update_key
)
501 btrfs_disk_key_to_cpu(&op_key
, &extent_op
->key
);
503 while ((n
= rb_prev(n
))) {
504 struct btrfs_delayed_ref_node
*node
;
505 node
= rb_entry(n
, struct btrfs_delayed_ref_node
,
507 if (node
->bytenr
!= head
->node
.bytenr
)
509 WARN_ON(node
->is_head
);
514 switch (node
->action
) {
515 case BTRFS_ADD_DELAYED_EXTENT
:
516 case BTRFS_UPDATE_DELAYED_HEAD
:
519 case BTRFS_ADD_DELAYED_REF
:
522 case BTRFS_DROP_DELAYED_REF
:
528 switch (node
->type
) {
529 case BTRFS_TREE_BLOCK_REF_KEY
: {
530 struct btrfs_delayed_tree_ref
*ref
;
532 ref
= btrfs_delayed_node_to_tree_ref(node
);
533 ret
= __add_prelim_ref(prefs
, ref
->root
, &op_key
,
534 ref
->level
+ 1, 0, node
->bytenr
,
535 node
->ref_mod
* sgn
);
538 case BTRFS_SHARED_BLOCK_REF_KEY
: {
539 struct btrfs_delayed_tree_ref
*ref
;
541 ref
= btrfs_delayed_node_to_tree_ref(node
);
542 ret
= __add_prelim_ref(prefs
, ref
->root
, NULL
,
543 ref
->level
+ 1, ref
->parent
,
545 node
->ref_mod
* sgn
);
548 case BTRFS_EXTENT_DATA_REF_KEY
: {
549 struct btrfs_delayed_data_ref
*ref
;
550 ref
= btrfs_delayed_node_to_data_ref(node
);
552 key
.objectid
= ref
->objectid
;
553 key
.type
= BTRFS_EXTENT_DATA_KEY
;
554 key
.offset
= ref
->offset
;
555 ret
= __add_prelim_ref(prefs
, ref
->root
, &key
, 0, 0,
557 node
->ref_mod
* sgn
);
560 case BTRFS_SHARED_DATA_REF_KEY
: {
561 struct btrfs_delayed_data_ref
*ref
;
563 ref
= btrfs_delayed_node_to_data_ref(node
);
565 key
.objectid
= ref
->objectid
;
566 key
.type
= BTRFS_EXTENT_DATA_KEY
;
567 key
.offset
= ref
->offset
;
568 ret
= __add_prelim_ref(prefs
, ref
->root
, &key
, 0,
569 ref
->parent
, node
->bytenr
,
570 node
->ref_mod
* sgn
);
583 * add all inline backrefs for bytenr to the list
585 static int __add_inline_refs(struct btrfs_fs_info
*fs_info
,
586 struct btrfs_path
*path
, u64 bytenr
,
587 int *info_level
, struct list_head
*prefs
)
591 struct extent_buffer
*leaf
;
592 struct btrfs_key key
;
595 struct btrfs_extent_item
*ei
;
600 * enumerate all inline refs
602 leaf
= path
->nodes
[0];
603 slot
= path
->slots
[0];
605 item_size
= btrfs_item_size_nr(leaf
, slot
);
606 BUG_ON(item_size
< sizeof(*ei
));
608 ei
= btrfs_item_ptr(leaf
, slot
, struct btrfs_extent_item
);
609 flags
= btrfs_extent_flags(leaf
, ei
);
611 ptr
= (unsigned long)(ei
+ 1);
612 end
= (unsigned long)ei
+ item_size
;
614 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
615 struct btrfs_tree_block_info
*info
;
617 info
= (struct btrfs_tree_block_info
*)ptr
;
618 *info_level
= btrfs_tree_block_level(leaf
, info
);
619 ptr
+= sizeof(struct btrfs_tree_block_info
);
622 BUG_ON(!(flags
& BTRFS_EXTENT_FLAG_DATA
));
626 struct btrfs_extent_inline_ref
*iref
;
630 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
631 type
= btrfs_extent_inline_ref_type(leaf
, iref
);
632 offset
= btrfs_extent_inline_ref_offset(leaf
, iref
);
635 case BTRFS_SHARED_BLOCK_REF_KEY
:
636 ret
= __add_prelim_ref(prefs
, 0, NULL
,
637 *info_level
+ 1, offset
,
640 case BTRFS_SHARED_DATA_REF_KEY
: {
641 struct btrfs_shared_data_ref
*sdref
;
644 sdref
= (struct btrfs_shared_data_ref
*)(iref
+ 1);
645 count
= btrfs_shared_data_ref_count(leaf
, sdref
);
646 ret
= __add_prelim_ref(prefs
, 0, NULL
, 0, offset
,
650 case BTRFS_TREE_BLOCK_REF_KEY
:
651 ret
= __add_prelim_ref(prefs
, offset
, NULL
,
655 case BTRFS_EXTENT_DATA_REF_KEY
: {
656 struct btrfs_extent_data_ref
*dref
;
660 dref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
661 count
= btrfs_extent_data_ref_count(leaf
, dref
);
662 key
.objectid
= btrfs_extent_data_ref_objectid(leaf
,
664 key
.type
= BTRFS_EXTENT_DATA_KEY
;
665 key
.offset
= btrfs_extent_data_ref_offset(leaf
, dref
);
666 root
= btrfs_extent_data_ref_root(leaf
, dref
);
667 ret
= __add_prelim_ref(prefs
, root
, &key
, 0, 0,
675 ptr
+= btrfs_extent_inline_ref_size(type
);
682 * add all non-inline backrefs for bytenr to the list
684 static int __add_keyed_refs(struct btrfs_fs_info
*fs_info
,
685 struct btrfs_path
*path
, u64 bytenr
,
686 int info_level
, struct list_head
*prefs
)
688 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
691 struct extent_buffer
*leaf
;
692 struct btrfs_key key
;
695 ret
= btrfs_next_item(extent_root
, path
);
703 slot
= path
->slots
[0];
704 leaf
= path
->nodes
[0];
705 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
707 if (key
.objectid
!= bytenr
)
709 if (key
.type
< BTRFS_TREE_BLOCK_REF_KEY
)
711 if (key
.type
> BTRFS_SHARED_DATA_REF_KEY
)
715 case BTRFS_SHARED_BLOCK_REF_KEY
:
716 ret
= __add_prelim_ref(prefs
, 0, NULL
,
717 info_level
+ 1, key
.offset
,
720 case BTRFS_SHARED_DATA_REF_KEY
: {
721 struct btrfs_shared_data_ref
*sdref
;
724 sdref
= btrfs_item_ptr(leaf
, slot
,
725 struct btrfs_shared_data_ref
);
726 count
= btrfs_shared_data_ref_count(leaf
, sdref
);
727 ret
= __add_prelim_ref(prefs
, 0, NULL
, 0, key
.offset
,
731 case BTRFS_TREE_BLOCK_REF_KEY
:
732 ret
= __add_prelim_ref(prefs
, key
.offset
, NULL
,
736 case BTRFS_EXTENT_DATA_REF_KEY
: {
737 struct btrfs_extent_data_ref
*dref
;
741 dref
= btrfs_item_ptr(leaf
, slot
,
742 struct btrfs_extent_data_ref
);
743 count
= btrfs_extent_data_ref_count(leaf
, dref
);
744 key
.objectid
= btrfs_extent_data_ref_objectid(leaf
,
746 key
.type
= BTRFS_EXTENT_DATA_KEY
;
747 key
.offset
= btrfs_extent_data_ref_offset(leaf
, dref
);
748 root
= btrfs_extent_data_ref_root(leaf
, dref
);
749 ret
= __add_prelim_ref(prefs
, root
, &key
, 0, 0,
763 * this adds all existing backrefs (inline backrefs, backrefs and delayed
764 * refs) for the given bytenr to the refs list, merges duplicates and resolves
765 * indirect refs to their parent bytenr.
766 * When roots are found, they're added to the roots list
768 * FIXME some caching might speed things up
770 static int find_parent_nodes(struct btrfs_trans_handle
*trans
,
771 struct btrfs_fs_info
*fs_info
, u64 bytenr
,
772 u64 delayed_ref_seq
, u64 time_seq
,
773 struct ulist
*refs
, struct ulist
*roots
,
774 const u64
*extent_item_pos
)
776 struct btrfs_key key
;
777 struct btrfs_path
*path
;
778 struct btrfs_delayed_ref_root
*delayed_refs
= NULL
;
779 struct btrfs_delayed_ref_head
*head
;
782 int search_commit_root
= (trans
== BTRFS_BACKREF_SEARCH_COMMIT_ROOT
);
783 struct list_head prefs_delayed
;
784 struct list_head prefs
;
785 struct __prelim_ref
*ref
;
787 INIT_LIST_HEAD(&prefs
);
788 INIT_LIST_HEAD(&prefs_delayed
);
790 key
.objectid
= bytenr
;
791 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
792 key
.offset
= (u64
)-1;
794 path
= btrfs_alloc_path();
797 path
->search_commit_root
= !!search_commit_root
;
800 * grab both a lock on the path and a lock on the delayed ref head.
801 * We need both to get a consistent picture of how the refs look
802 * at a specified point in time
807 ret
= btrfs_search_slot(trans
, fs_info
->extent_root
, &key
, path
, 0, 0);
812 if (trans
!= BTRFS_BACKREF_SEARCH_COMMIT_ROOT
) {
814 * look if there are updates for this ref queued and lock the
817 delayed_refs
= &trans
->transaction
->delayed_refs
;
818 spin_lock(&delayed_refs
->lock
);
819 head
= btrfs_find_delayed_ref_head(trans
, bytenr
);
821 if (!mutex_trylock(&head
->mutex
)) {
822 atomic_inc(&head
->node
.refs
);
823 spin_unlock(&delayed_refs
->lock
);
825 btrfs_release_path(path
);
828 * Mutex was contended, block until it's
829 * released and try again
831 mutex_lock(&head
->mutex
);
832 mutex_unlock(&head
->mutex
);
833 btrfs_put_delayed_ref(&head
->node
);
836 ret
= __add_delayed_refs(head
, delayed_ref_seq
,
839 spin_unlock(&delayed_refs
->lock
);
843 spin_unlock(&delayed_refs
->lock
);
846 if (path
->slots
[0]) {
847 struct extent_buffer
*leaf
;
851 leaf
= path
->nodes
[0];
852 slot
= path
->slots
[0];
853 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
854 if (key
.objectid
== bytenr
&&
855 key
.type
== BTRFS_EXTENT_ITEM_KEY
) {
856 ret
= __add_inline_refs(fs_info
, path
, bytenr
,
857 &info_level
, &prefs
);
860 ret
= __add_keyed_refs(fs_info
, path
, bytenr
,
866 btrfs_release_path(path
);
868 list_splice_init(&prefs_delayed
, &prefs
);
870 ret
= __add_missing_keys(fs_info
, &prefs
);
874 ret
= __merge_refs(&prefs
, 1);
878 ret
= __resolve_indirect_refs(fs_info
, search_commit_root
, time_seq
,
879 &prefs
, extent_item_pos
);
883 ret
= __merge_refs(&prefs
, 2);
887 while (!list_empty(&prefs
)) {
888 ref
= list_first_entry(&prefs
, struct __prelim_ref
, list
);
889 list_del(&ref
->list
);
892 if (ref
->count
&& ref
->root_id
&& ref
->parent
== 0) {
893 /* no parent == root of tree */
894 ret
= ulist_add(roots
, ref
->root_id
, 0, GFP_NOFS
);
897 if (ref
->count
&& ref
->parent
) {
898 struct extent_inode_elem
*eie
= NULL
;
899 if (extent_item_pos
&& !ref
->inode_list
) {
901 struct extent_buffer
*eb
;
902 bsz
= btrfs_level_size(fs_info
->extent_root
,
904 eb
= read_tree_block(fs_info
->extent_root
,
905 ref
->parent
, bsz
, 0);
907 ret
= find_extent_in_eb(eb
, bytenr
,
908 *extent_item_pos
, &eie
);
909 ref
->inode_list
= eie
;
910 free_extent_buffer(eb
);
912 ret
= ulist_add_merge(refs
, ref
->parent
,
913 (unsigned long)ref
->inode_list
,
914 (unsigned long *)&eie
, GFP_NOFS
);
915 if (!ret
&& extent_item_pos
) {
917 * we've recorded that parent, so we must extend
918 * its inode list here
923 eie
->next
= ref
->inode_list
;
932 mutex_unlock(&head
->mutex
);
933 btrfs_free_path(path
);
934 while (!list_empty(&prefs
)) {
935 ref
= list_first_entry(&prefs
, struct __prelim_ref
, list
);
936 list_del(&ref
->list
);
939 while (!list_empty(&prefs_delayed
)) {
940 ref
= list_first_entry(&prefs_delayed
, struct __prelim_ref
,
942 list_del(&ref
->list
);
949 static void free_leaf_list(struct ulist
*blocks
)
951 struct ulist_node
*node
= NULL
;
952 struct extent_inode_elem
*eie
;
953 struct extent_inode_elem
*eie_next
;
954 struct ulist_iterator uiter
;
956 ULIST_ITER_INIT(&uiter
);
957 while ((node
= ulist_next(blocks
, &uiter
))) {
960 eie
= (struct extent_inode_elem
*)node
->aux
;
961 for (; eie
; eie
= eie_next
) {
962 eie_next
= eie
->next
;
972 * Finds all leafs with a reference to the specified combination of bytenr and
973 * offset. key_list_head will point to a list of corresponding keys (caller must
974 * free each list element). The leafs will be stored in the leafs ulist, which
975 * must be freed with ulist_free.
977 * returns 0 on success, <0 on error
979 static int btrfs_find_all_leafs(struct btrfs_trans_handle
*trans
,
980 struct btrfs_fs_info
*fs_info
, u64 bytenr
,
981 u64 delayed_ref_seq
, u64 time_seq
,
982 struct ulist
**leafs
,
983 const u64
*extent_item_pos
)
988 tmp
= ulist_alloc(GFP_NOFS
);
991 *leafs
= ulist_alloc(GFP_NOFS
);
997 ret
= find_parent_nodes(trans
, fs_info
, bytenr
, delayed_ref_seq
,
998 time_seq
, *leafs
, tmp
, extent_item_pos
);
1001 if (ret
< 0 && ret
!= -ENOENT
) {
1002 free_leaf_list(*leafs
);
1010 * walk all backrefs for a given extent to find all roots that reference this
1011 * extent. Walking a backref means finding all extents that reference this
1012 * extent and in turn walk the backrefs of those, too. Naturally this is a
1013 * recursive process, but here it is implemented in an iterative fashion: We
1014 * find all referencing extents for the extent in question and put them on a
1015 * list. In turn, we find all referencing extents for those, further appending
1016 * to the list. The way we iterate the list allows adding more elements after
1017 * the current while iterating. The process stops when we reach the end of the
1018 * list. Found roots are added to the roots list.
1020 * returns 0 on success, < 0 on error.
1022 int btrfs_find_all_roots(struct btrfs_trans_handle
*trans
,
1023 struct btrfs_fs_info
*fs_info
, u64 bytenr
,
1024 u64 delayed_ref_seq
, u64 time_seq
,
1025 struct ulist
**roots
)
1028 struct ulist_node
*node
= NULL
;
1029 struct ulist_iterator uiter
;
1032 tmp
= ulist_alloc(GFP_NOFS
);
1035 *roots
= ulist_alloc(GFP_NOFS
);
1041 ULIST_ITER_INIT(&uiter
);
1043 ret
= find_parent_nodes(trans
, fs_info
, bytenr
, delayed_ref_seq
,
1044 time_seq
, tmp
, *roots
, NULL
);
1045 if (ret
< 0 && ret
!= -ENOENT
) {
1050 node
= ulist_next(tmp
, &uiter
);
1061 static int __inode_info(u64 inum
, u64 ioff
, u8 key_type
,
1062 struct btrfs_root
*fs_root
, struct btrfs_path
*path
,
1063 struct btrfs_key
*found_key
)
1066 struct btrfs_key key
;
1067 struct extent_buffer
*eb
;
1069 key
.type
= key_type
;
1070 key
.objectid
= inum
;
1073 ret
= btrfs_search_slot(NULL
, fs_root
, &key
, path
, 0, 0);
1077 eb
= path
->nodes
[0];
1078 if (ret
&& path
->slots
[0] >= btrfs_header_nritems(eb
)) {
1079 ret
= btrfs_next_leaf(fs_root
, path
);
1082 eb
= path
->nodes
[0];
1085 btrfs_item_key_to_cpu(eb
, found_key
, path
->slots
[0]);
1086 if (found_key
->type
!= key
.type
|| found_key
->objectid
!= key
.objectid
)
1093 * this makes the path point to (inum INODE_ITEM ioff)
1095 int inode_item_info(u64 inum
, u64 ioff
, struct btrfs_root
*fs_root
,
1096 struct btrfs_path
*path
)
1098 struct btrfs_key key
;
1099 return __inode_info(inum
, ioff
, BTRFS_INODE_ITEM_KEY
, fs_root
, path
,
1103 static int inode_ref_info(u64 inum
, u64 ioff
, struct btrfs_root
*fs_root
,
1104 struct btrfs_path
*path
,
1105 struct btrfs_key
*found_key
)
1107 return __inode_info(inum
, ioff
, BTRFS_INODE_REF_KEY
, fs_root
, path
,
1112 * this iterates to turn a btrfs_inode_ref into a full filesystem path. elements
1113 * of the path are separated by '/' and the path is guaranteed to be
1114 * 0-terminated. the path is only given within the current file system.
1115 * Therefore, it never starts with a '/'. the caller is responsible to provide
1116 * "size" bytes in "dest". the dest buffer will be filled backwards. finally,
1117 * the start point of the resulting string is returned. this pointer is within
1119 * in case the path buffer would overflow, the pointer is decremented further
1120 * as if output was written to the buffer, though no more output is actually
1121 * generated. that way, the caller can determine how much space would be
1122 * required for the path to fit into the buffer. in that case, the returned
1123 * value will be smaller than dest. callers must check this!
1125 static char *iref_to_path(struct btrfs_root
*fs_root
, struct btrfs_path
*path
,
1126 struct btrfs_inode_ref
*iref
,
1127 struct extent_buffer
*eb_in
, u64 parent
,
1128 char *dest
, u32 size
)
1134 s64 bytes_left
= size
- 1;
1135 struct extent_buffer
*eb
= eb_in
;
1136 struct btrfs_key found_key
;
1137 int leave_spinning
= path
->leave_spinning
;
1139 if (bytes_left
>= 0)
1140 dest
[bytes_left
] = '\0';
1142 path
->leave_spinning
= 1;
1144 len
= btrfs_inode_ref_name_len(eb
, iref
);
1146 if (bytes_left
>= 0)
1147 read_extent_buffer(eb
, dest
+ bytes_left
,
1148 (unsigned long)(iref
+ 1), len
);
1150 btrfs_tree_read_unlock_blocking(eb
);
1151 free_extent_buffer(eb
);
1153 ret
= inode_ref_info(parent
, 0, fs_root
, path
, &found_key
);
1158 next_inum
= found_key
.offset
;
1160 /* regular exit ahead */
1161 if (parent
== next_inum
)
1164 slot
= path
->slots
[0];
1165 eb
= path
->nodes
[0];
1166 /* make sure we can use eb after releasing the path */
1168 atomic_inc(&eb
->refs
);
1169 btrfs_tree_read_lock(eb
);
1170 btrfs_set_lock_blocking_rw(eb
, BTRFS_READ_LOCK
);
1172 btrfs_release_path(path
);
1174 iref
= btrfs_item_ptr(eb
, slot
, struct btrfs_inode_ref
);
1177 if (bytes_left
>= 0)
1178 dest
[bytes_left
] = '/';
1181 btrfs_release_path(path
);
1182 path
->leave_spinning
= leave_spinning
;
1185 return ERR_PTR(ret
);
1187 return dest
+ bytes_left
;
1191 * this makes the path point to (logical EXTENT_ITEM *)
1192 * returns BTRFS_EXTENT_FLAG_DATA for data, BTRFS_EXTENT_FLAG_TREE_BLOCK for
1193 * tree blocks and <0 on error.
1195 int extent_from_logical(struct btrfs_fs_info
*fs_info
, u64 logical
,
1196 struct btrfs_path
*path
, struct btrfs_key
*found_key
)
1201 struct extent_buffer
*eb
;
1202 struct btrfs_extent_item
*ei
;
1203 struct btrfs_key key
;
1205 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
1206 key
.objectid
= logical
;
1207 key
.offset
= (u64
)-1;
1209 ret
= btrfs_search_slot(NULL
, fs_info
->extent_root
, &key
, path
, 0, 0);
1212 ret
= btrfs_previous_item(fs_info
->extent_root
, path
,
1213 0, BTRFS_EXTENT_ITEM_KEY
);
1217 btrfs_item_key_to_cpu(path
->nodes
[0], found_key
, path
->slots
[0]);
1218 if (found_key
->type
!= BTRFS_EXTENT_ITEM_KEY
||
1219 found_key
->objectid
> logical
||
1220 found_key
->objectid
+ found_key
->offset
<= logical
) {
1221 pr_debug("logical %llu is not within any extent\n",
1222 (unsigned long long)logical
);
1226 eb
= path
->nodes
[0];
1227 item_size
= btrfs_item_size_nr(eb
, path
->slots
[0]);
1228 BUG_ON(item_size
< sizeof(*ei
));
1230 ei
= btrfs_item_ptr(eb
, path
->slots
[0], struct btrfs_extent_item
);
1231 flags
= btrfs_extent_flags(eb
, ei
);
1233 pr_debug("logical %llu is at position %llu within the extent (%llu "
1234 "EXTENT_ITEM %llu) flags %#llx size %u\n",
1235 (unsigned long long)logical
,
1236 (unsigned long long)(logical
- found_key
->objectid
),
1237 (unsigned long long)found_key
->objectid
,
1238 (unsigned long long)found_key
->offset
,
1239 (unsigned long long)flags
, item_size
);
1240 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
)
1241 return BTRFS_EXTENT_FLAG_TREE_BLOCK
;
1242 if (flags
& BTRFS_EXTENT_FLAG_DATA
)
1243 return BTRFS_EXTENT_FLAG_DATA
;
1249 * helper function to iterate extent inline refs. ptr must point to a 0 value
1250 * for the first call and may be modified. it is used to track state.
1251 * if more refs exist, 0 is returned and the next call to
1252 * __get_extent_inline_ref must pass the modified ptr parameter to get the
1253 * next ref. after the last ref was processed, 1 is returned.
1254 * returns <0 on error
1256 static int __get_extent_inline_ref(unsigned long *ptr
, struct extent_buffer
*eb
,
1257 struct btrfs_extent_item
*ei
, u32 item_size
,
1258 struct btrfs_extent_inline_ref
**out_eiref
,
1263 struct btrfs_tree_block_info
*info
;
1267 flags
= btrfs_extent_flags(eb
, ei
);
1268 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
1269 info
= (struct btrfs_tree_block_info
*)(ei
+ 1);
1271 (struct btrfs_extent_inline_ref
*)(info
+ 1);
1273 *out_eiref
= (struct btrfs_extent_inline_ref
*)(ei
+ 1);
1275 *ptr
= (unsigned long)*out_eiref
;
1276 if ((void *)*ptr
>= (void *)ei
+ item_size
)
1280 end
= (unsigned long)ei
+ item_size
;
1281 *out_eiref
= (struct btrfs_extent_inline_ref
*)*ptr
;
1282 *out_type
= btrfs_extent_inline_ref_type(eb
, *out_eiref
);
1284 *ptr
+= btrfs_extent_inline_ref_size(*out_type
);
1285 WARN_ON(*ptr
> end
);
1287 return 1; /* last */
1293 * reads the tree block backref for an extent. tree level and root are returned
1294 * through out_level and out_root. ptr must point to a 0 value for the first
1295 * call and may be modified (see __get_extent_inline_ref comment).
1296 * returns 0 if data was provided, 1 if there was no more data to provide or
1299 int tree_backref_for_extent(unsigned long *ptr
, struct extent_buffer
*eb
,
1300 struct btrfs_extent_item
*ei
, u32 item_size
,
1301 u64
*out_root
, u8
*out_level
)
1305 struct btrfs_tree_block_info
*info
;
1306 struct btrfs_extent_inline_ref
*eiref
;
1308 if (*ptr
== (unsigned long)-1)
1312 ret
= __get_extent_inline_ref(ptr
, eb
, ei
, item_size
,
1317 if (type
== BTRFS_TREE_BLOCK_REF_KEY
||
1318 type
== BTRFS_SHARED_BLOCK_REF_KEY
)
1325 /* we can treat both ref types equally here */
1326 info
= (struct btrfs_tree_block_info
*)(ei
+ 1);
1327 *out_root
= btrfs_extent_inline_ref_offset(eb
, eiref
);
1328 *out_level
= btrfs_tree_block_level(eb
, info
);
1331 *ptr
= (unsigned long)-1;
1336 static int iterate_leaf_refs(struct extent_inode_elem
*inode_list
,
1337 u64 root
, u64 extent_item_objectid
,
1338 iterate_extent_inodes_t
*iterate
, void *ctx
)
1340 struct extent_inode_elem
*eie
;
1343 for (eie
= inode_list
; eie
; eie
= eie
->next
) {
1344 pr_debug("ref for %llu resolved, key (%llu EXTEND_DATA %llu), "
1345 "root %llu\n", extent_item_objectid
,
1346 eie
->inum
, eie
->offset
, root
);
1347 ret
= iterate(eie
->inum
, eie
->offset
, root
, ctx
);
1349 pr_debug("stopping iteration for %llu due to ret=%d\n",
1350 extent_item_objectid
, ret
);
1359 * calls iterate() for every inode that references the extent identified by
1360 * the given parameters.
1361 * when the iterator function returns a non-zero value, iteration stops.
1363 int iterate_extent_inodes(struct btrfs_fs_info
*fs_info
,
1364 u64 extent_item_objectid
, u64 extent_item_pos
,
1365 int search_commit_root
,
1366 iterate_extent_inodes_t
*iterate
, void *ctx
)
1369 struct list_head data_refs
= LIST_HEAD_INIT(data_refs
);
1370 struct list_head shared_refs
= LIST_HEAD_INIT(shared_refs
);
1371 struct btrfs_trans_handle
*trans
;
1372 struct ulist
*refs
= NULL
;
1373 struct ulist
*roots
= NULL
;
1374 struct ulist_node
*ref_node
= NULL
;
1375 struct ulist_node
*root_node
= NULL
;
1376 struct seq_list seq_elem
= {};
1377 struct seq_list tree_mod_seq_elem
= {};
1378 struct ulist_iterator ref_uiter
;
1379 struct ulist_iterator root_uiter
;
1380 struct btrfs_delayed_ref_root
*delayed_refs
= NULL
;
1382 pr_debug("resolving all inodes for extent %llu\n",
1383 extent_item_objectid
);
1385 if (search_commit_root
) {
1386 trans
= BTRFS_BACKREF_SEARCH_COMMIT_ROOT
;
1388 trans
= btrfs_join_transaction(fs_info
->extent_root
);
1390 return PTR_ERR(trans
);
1392 delayed_refs
= &trans
->transaction
->delayed_refs
;
1393 spin_lock(&delayed_refs
->lock
);
1394 btrfs_get_delayed_seq(delayed_refs
, &seq_elem
);
1395 spin_unlock(&delayed_refs
->lock
);
1396 btrfs_get_tree_mod_seq(fs_info
, &tree_mod_seq_elem
);
1399 ret
= btrfs_find_all_leafs(trans
, fs_info
, extent_item_objectid
,
1400 seq_elem
.seq
, tree_mod_seq_elem
.seq
, &refs
,
1405 ULIST_ITER_INIT(&ref_uiter
);
1406 while (!ret
&& (ref_node
= ulist_next(refs
, &ref_uiter
))) {
1407 ret
= btrfs_find_all_roots(trans
, fs_info
, ref_node
->val
,
1409 tree_mod_seq_elem
.seq
, &roots
);
1412 ULIST_ITER_INIT(&root_uiter
);
1413 while (!ret
&& (root_node
= ulist_next(roots
, &root_uiter
))) {
1414 pr_debug("root %llu references leaf %llu, data list "
1415 "%#lx\n", root_node
->val
, ref_node
->val
,
1417 ret
= iterate_leaf_refs(
1418 (struct extent_inode_elem
*)ref_node
->aux
,
1419 root_node
->val
, extent_item_objectid
,
1426 free_leaf_list(refs
);
1429 if (!search_commit_root
) {
1430 btrfs_put_tree_mod_seq(fs_info
, &tree_mod_seq_elem
);
1431 btrfs_put_delayed_seq(delayed_refs
, &seq_elem
);
1432 btrfs_end_transaction(trans
, fs_info
->extent_root
);
1438 int iterate_inodes_from_logical(u64 logical
, struct btrfs_fs_info
*fs_info
,
1439 struct btrfs_path
*path
,
1440 iterate_extent_inodes_t
*iterate
, void *ctx
)
1443 u64 extent_item_pos
;
1444 struct btrfs_key found_key
;
1445 int search_commit_root
= path
->search_commit_root
;
1447 ret
= extent_from_logical(fs_info
, logical
, path
,
1449 btrfs_release_path(path
);
1450 if (ret
& BTRFS_EXTENT_FLAG_TREE_BLOCK
)
1455 extent_item_pos
= logical
- found_key
.objectid
;
1456 ret
= iterate_extent_inodes(fs_info
, found_key
.objectid
,
1457 extent_item_pos
, search_commit_root
,
1463 static int iterate_irefs(u64 inum
, struct btrfs_root
*fs_root
,
1464 struct btrfs_path
*path
,
1465 iterate_irefs_t
*iterate
, void *ctx
)
1474 struct extent_buffer
*eb
;
1475 struct btrfs_item
*item
;
1476 struct btrfs_inode_ref
*iref
;
1477 struct btrfs_key found_key
;
1480 path
->leave_spinning
= 1;
1481 ret
= inode_ref_info(inum
, parent
? parent
+1 : 0, fs_root
, path
,
1486 ret
= found
? 0 : -ENOENT
;
1491 parent
= found_key
.offset
;
1492 slot
= path
->slots
[0];
1493 eb
= path
->nodes
[0];
1494 /* make sure we can use eb after releasing the path */
1495 atomic_inc(&eb
->refs
);
1496 btrfs_tree_read_lock(eb
);
1497 btrfs_set_lock_blocking_rw(eb
, BTRFS_READ_LOCK
);
1498 btrfs_release_path(path
);
1500 item
= btrfs_item_nr(eb
, slot
);
1501 iref
= btrfs_item_ptr(eb
, slot
, struct btrfs_inode_ref
);
1503 for (cur
= 0; cur
< btrfs_item_size(eb
, item
); cur
+= len
) {
1504 name_len
= btrfs_inode_ref_name_len(eb
, iref
);
1505 /* path must be released before calling iterate()! */
1506 pr_debug("following ref at offset %u for inode %llu in "
1508 (unsigned long long)found_key
.objectid
,
1509 (unsigned long long)fs_root
->objectid
);
1510 ret
= iterate(parent
, iref
, eb
, ctx
);
1513 len
= sizeof(*iref
) + name_len
;
1514 iref
= (struct btrfs_inode_ref
*)((char *)iref
+ len
);
1516 btrfs_tree_read_unlock_blocking(eb
);
1517 free_extent_buffer(eb
);
1520 btrfs_release_path(path
);
1526 * returns 0 if the path could be dumped (probably truncated)
1527 * returns <0 in case of an error
1529 static int inode_to_path(u64 inum
, struct btrfs_inode_ref
*iref
,
1530 struct extent_buffer
*eb
, void *ctx
)
1532 struct inode_fs_paths
*ipath
= ctx
;
1535 int i
= ipath
->fspath
->elem_cnt
;
1536 const int s_ptr
= sizeof(char *);
1539 bytes_left
= ipath
->fspath
->bytes_left
> s_ptr
?
1540 ipath
->fspath
->bytes_left
- s_ptr
: 0;
1542 fspath_min
= (char *)ipath
->fspath
->val
+ (i
+ 1) * s_ptr
;
1543 fspath
= iref_to_path(ipath
->fs_root
, ipath
->btrfs_path
, iref
, eb
,
1544 inum
, fspath_min
, bytes_left
);
1546 return PTR_ERR(fspath
);
1548 if (fspath
> fspath_min
) {
1549 pr_debug("path resolved: %s\n", fspath
);
1550 ipath
->fspath
->val
[i
] = (u64
)(unsigned long)fspath
;
1551 ++ipath
->fspath
->elem_cnt
;
1552 ipath
->fspath
->bytes_left
= fspath
- fspath_min
;
1554 pr_debug("missed path, not enough space. missing bytes: %lu, "
1555 "constructed so far: %s\n",
1556 (unsigned long)(fspath_min
- fspath
), fspath_min
);
1557 ++ipath
->fspath
->elem_missed
;
1558 ipath
->fspath
->bytes_missing
+= fspath_min
- fspath
;
1559 ipath
->fspath
->bytes_left
= 0;
1566 * this dumps all file system paths to the inode into the ipath struct, provided
1567 * is has been created large enough. each path is zero-terminated and accessed
1568 * from ipath->fspath->val[i].
1569 * when it returns, there are ipath->fspath->elem_cnt number of paths available
1570 * in ipath->fspath->val[]. when the allocated space wasn't sufficient, the
1571 * number of missed paths in recored in ipath->fspath->elem_missed, otherwise,
1572 * it's zero. ipath->fspath->bytes_missing holds the number of bytes that would
1573 * have been needed to return all paths.
1575 int paths_from_inode(u64 inum
, struct inode_fs_paths
*ipath
)
1577 return iterate_irefs(inum
, ipath
->fs_root
, ipath
->btrfs_path
,
1578 inode_to_path
, ipath
);
1581 struct btrfs_data_container
*init_data_container(u32 total_bytes
)
1583 struct btrfs_data_container
*data
;
1586 alloc_bytes
= max_t(size_t, total_bytes
, sizeof(*data
));
1587 data
= kmalloc(alloc_bytes
, GFP_NOFS
);
1589 return ERR_PTR(-ENOMEM
);
1591 if (total_bytes
>= sizeof(*data
)) {
1592 data
->bytes_left
= total_bytes
- sizeof(*data
);
1593 data
->bytes_missing
= 0;
1595 data
->bytes_missing
= sizeof(*data
) - total_bytes
;
1596 data
->bytes_left
= 0;
1600 data
->elem_missed
= 0;
1606 * allocates space to return multiple file system paths for an inode.
1607 * total_bytes to allocate are passed, note that space usable for actual path
1608 * information will be total_bytes - sizeof(struct inode_fs_paths).
1609 * the returned pointer must be freed with free_ipath() in the end.
1611 struct inode_fs_paths
*init_ipath(s32 total_bytes
, struct btrfs_root
*fs_root
,
1612 struct btrfs_path
*path
)
1614 struct inode_fs_paths
*ifp
;
1615 struct btrfs_data_container
*fspath
;
1617 fspath
= init_data_container(total_bytes
);
1619 return (void *)fspath
;
1621 ifp
= kmalloc(sizeof(*ifp
), GFP_NOFS
);
1624 return ERR_PTR(-ENOMEM
);
1627 ifp
->btrfs_path
= path
;
1628 ifp
->fspath
= fspath
;
1629 ifp
->fs_root
= fs_root
;
1634 void free_ipath(struct inode_fs_paths
*ipath
)
1638 kfree(ipath
->fspath
);