2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/sched.h>
22 #include "transaction.h"
23 #include "print-tree.h"
26 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
27 *root
, struct btrfs_path
*path
, int level
);
28 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
29 *root
, struct btrfs_key
*ins_key
,
30 struct btrfs_path
*path
, int data_size
, int extend
);
31 static int push_node_left(struct btrfs_trans_handle
*trans
,
32 struct btrfs_root
*root
, struct extent_buffer
*dst
,
33 struct extent_buffer
*src
, int empty
);
34 static int balance_node_right(struct btrfs_trans_handle
*trans
,
35 struct btrfs_root
*root
,
36 struct extent_buffer
*dst_buf
,
37 struct extent_buffer
*src_buf
);
38 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
39 struct btrfs_path
*path
, int level
, int slot
);
41 inline void btrfs_init_path(struct btrfs_path
*p
)
43 memset(p
, 0, sizeof(*p
));
46 struct btrfs_path
*btrfs_alloc_path(void)
48 struct btrfs_path
*path
;
49 path
= kmem_cache_alloc(btrfs_path_cachep
, GFP_NOFS
);
51 btrfs_init_path(path
);
57 void btrfs_free_path(struct btrfs_path
*p
)
59 btrfs_release_path(NULL
, p
);
60 kmem_cache_free(btrfs_path_cachep
, p
);
63 void btrfs_release_path(struct btrfs_root
*root
, struct btrfs_path
*p
)
67 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++) {
72 btrfs_tree_unlock(p
->nodes
[i
]);
75 free_extent_buffer(p
->nodes
[i
]);
80 struct extent_buffer
*btrfs_root_node(struct btrfs_root
*root
)
82 struct extent_buffer
*eb
;
83 spin_lock(&root
->node_lock
);
85 extent_buffer_get(eb
);
86 spin_unlock(&root
->node_lock
);
90 struct extent_buffer
*btrfs_lock_root_node(struct btrfs_root
*root
)
92 struct extent_buffer
*eb
;
95 eb
= btrfs_root_node(root
);
98 spin_lock(&root
->node_lock
);
99 if (eb
== root
->node
) {
100 spin_unlock(&root
->node_lock
);
103 spin_unlock(&root
->node_lock
);
105 btrfs_tree_unlock(eb
);
106 free_extent_buffer(eb
);
111 static void add_root_to_dirty_list(struct btrfs_root
*root
)
113 if (root
->track_dirty
&& list_empty(&root
->dirty_list
)) {
114 list_add(&root
->dirty_list
,
115 &root
->fs_info
->dirty_cowonly_roots
);
119 int btrfs_copy_root(struct btrfs_trans_handle
*trans
,
120 struct btrfs_root
*root
,
121 struct extent_buffer
*buf
,
122 struct extent_buffer
**cow_ret
, u64 new_root_objectid
)
124 struct extent_buffer
*cow
;
128 struct btrfs_key first_key
;
129 struct btrfs_root
*new_root
;
131 new_root
= kmalloc(sizeof(*new_root
), GFP_NOFS
);
135 memcpy(new_root
, root
, sizeof(*new_root
));
136 new_root
->root_key
.objectid
= new_root_objectid
;
138 WARN_ON(root
->ref_cows
&& trans
->transid
!=
139 root
->fs_info
->running_transaction
->transid
);
140 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
142 level
= btrfs_header_level(buf
);
143 nritems
= btrfs_header_nritems(buf
);
146 btrfs_item_key_to_cpu(buf
, &first_key
, 0);
148 btrfs_node_key_to_cpu(buf
, &first_key
, 0);
150 first_key
.objectid
= 0;
152 cow
= btrfs_alloc_free_block(trans
, new_root
, buf
->len
,
154 trans
->transid
, first_key
.objectid
,
155 level
, buf
->start
, 0);
161 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
162 btrfs_set_header_bytenr(cow
, cow
->start
);
163 btrfs_set_header_generation(cow
, trans
->transid
);
164 btrfs_set_header_owner(cow
, new_root_objectid
);
165 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
167 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
168 ret
= btrfs_inc_ref(trans
, new_root
, buf
, 0);
174 btrfs_mark_buffer_dirty(cow
);
179 int __btrfs_cow_block(struct btrfs_trans_handle
*trans
,
180 struct btrfs_root
*root
,
181 struct extent_buffer
*buf
,
182 struct extent_buffer
*parent
, int parent_slot
,
183 struct extent_buffer
**cow_ret
,
184 u64 search_start
, u64 empty_size
)
187 struct extent_buffer
*cow
;
190 int different_trans
= 0;
193 struct btrfs_key first_key
;
198 WARN_ON(!btrfs_tree_locked(buf
));
200 if (root
->ref_cows
) {
201 root_gen
= trans
->transid
;
205 WARN_ON(root
->ref_cows
&& trans
->transid
!=
206 root
->fs_info
->running_transaction
->transid
);
207 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
209 level
= btrfs_header_level(buf
);
210 nritems
= btrfs_header_nritems(buf
);
213 btrfs_item_key_to_cpu(buf
, &first_key
, 0);
215 btrfs_node_key_to_cpu(buf
, &first_key
, 0);
217 first_key
.objectid
= 0;
219 cow
= btrfs_alloc_free_block(trans
, root
, buf
->len
,
220 root
->root_key
.objectid
,
221 root_gen
, first_key
.objectid
, level
,
222 search_start
, empty_size
);
226 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
227 btrfs_set_header_bytenr(cow
, cow
->start
);
228 btrfs_set_header_generation(cow
, trans
->transid
);
229 btrfs_set_header_owner(cow
, root
->root_key
.objectid
);
230 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
232 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
233 if (btrfs_header_generation(buf
) != trans
->transid
) {
235 ret
= btrfs_inc_ref(trans
, root
, buf
, 1);
239 clean_tree_block(trans
, root
, buf
);
242 if (buf
== root
->node
) {
243 WARN_ON(parent
&& parent
!= buf
);
244 root_gen
= btrfs_header_generation(buf
);
246 spin_lock(&root
->node_lock
);
248 extent_buffer_get(cow
);
249 spin_unlock(&root
->node_lock
);
251 if (buf
!= root
->commit_root
) {
252 btrfs_free_extent(trans
, root
, buf
->start
,
253 buf
->len
, root
->root_key
.objectid
,
256 free_extent_buffer(buf
);
257 add_root_to_dirty_list(root
);
259 root_gen
= btrfs_header_generation(parent
);
260 btrfs_set_node_blockptr(parent
, parent_slot
,
262 WARN_ON(trans
->transid
== 0);
263 btrfs_set_node_ptr_generation(parent
, parent_slot
,
265 btrfs_mark_buffer_dirty(parent
);
266 WARN_ON(btrfs_header_generation(parent
) != trans
->transid
);
267 btrfs_free_extent(trans
, root
, buf
->start
, buf
->len
,
268 btrfs_header_owner(parent
), root_gen
,
272 btrfs_tree_unlock(buf
);
273 free_extent_buffer(buf
);
274 btrfs_mark_buffer_dirty(cow
);
279 int btrfs_cow_block(struct btrfs_trans_handle
*trans
,
280 struct btrfs_root
*root
, struct extent_buffer
*buf
,
281 struct extent_buffer
*parent
, int parent_slot
,
282 struct extent_buffer
**cow_ret
)
288 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
289 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
290 root
->fs_info
->running_transaction
->transid
);
293 if (trans
->transid
!= root
->fs_info
->generation
) {
294 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
295 root
->fs_info
->generation
);
299 header_trans
= btrfs_header_generation(buf
);
300 spin_lock(&root
->fs_info
->hash_lock
);
301 if (header_trans
== trans
->transid
&&
302 !btrfs_header_flag(buf
, BTRFS_HEADER_FLAG_WRITTEN
)) {
304 spin_unlock(&root
->fs_info
->hash_lock
);
307 spin_unlock(&root
->fs_info
->hash_lock
);
308 search_start
= buf
->start
& ~((u64
)(1024 * 1024 * 1024) - 1);
309 ret
= __btrfs_cow_block(trans
, root
, buf
, parent
,
310 parent_slot
, cow_ret
, search_start
, 0);
314 static int close_blocks(u64 blocknr
, u64 other
, u32 blocksize
)
316 if (blocknr
< other
&& other
- (blocknr
+ blocksize
) < 32768)
318 if (blocknr
> other
&& blocknr
- (other
+ blocksize
) < 32768)
324 * compare two keys in a memcmp fashion
326 static int comp_keys(struct btrfs_disk_key
*disk
, struct btrfs_key
*k2
)
330 btrfs_disk_key_to_cpu(&k1
, disk
);
332 if (k1
.objectid
> k2
->objectid
)
334 if (k1
.objectid
< k2
->objectid
)
336 if (k1
.type
> k2
->type
)
338 if (k1
.type
< k2
->type
)
340 if (k1
.offset
> k2
->offset
)
342 if (k1
.offset
< k2
->offset
)
348 int btrfs_realloc_node(struct btrfs_trans_handle
*trans
,
349 struct btrfs_root
*root
, struct extent_buffer
*parent
,
350 int start_slot
, int cache_only
, u64
*last_ret
,
351 struct btrfs_key
*progress
)
353 struct extent_buffer
*cur
;
356 u64 search_start
= *last_ret
;
366 int progress_passed
= 0;
367 struct btrfs_disk_key disk_key
;
369 parent_level
= btrfs_header_level(parent
);
370 if (cache_only
&& parent_level
!= 1)
373 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
374 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
375 root
->fs_info
->running_transaction
->transid
);
378 if (trans
->transid
!= root
->fs_info
->generation
) {
379 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
380 root
->fs_info
->generation
);
384 parent_nritems
= btrfs_header_nritems(parent
);
385 blocksize
= btrfs_level_size(root
, parent_level
- 1);
386 end_slot
= parent_nritems
;
388 if (parent_nritems
== 1)
391 for (i
= start_slot
; i
< end_slot
; i
++) {
394 if (!parent
->map_token
) {
395 map_extent_buffer(parent
,
396 btrfs_node_key_ptr_offset(i
),
397 sizeof(struct btrfs_key_ptr
),
398 &parent
->map_token
, &parent
->kaddr
,
399 &parent
->map_start
, &parent
->map_len
,
402 btrfs_node_key(parent
, &disk_key
, i
);
403 if (!progress_passed
&& comp_keys(&disk_key
, progress
) < 0)
407 blocknr
= btrfs_node_blockptr(parent
, i
);
408 gen
= btrfs_node_ptr_generation(parent
, i
);
410 last_block
= blocknr
;
413 other
= btrfs_node_blockptr(parent
, i
- 1);
414 close
= close_blocks(blocknr
, other
, blocksize
);
416 if (!close
&& i
< end_slot
- 2) {
417 other
= btrfs_node_blockptr(parent
, i
+ 1);
418 close
= close_blocks(blocknr
, other
, blocksize
);
421 last_block
= blocknr
;
424 if (parent
->map_token
) {
425 unmap_extent_buffer(parent
, parent
->map_token
,
427 parent
->map_token
= NULL
;
430 cur
= btrfs_find_tree_block(root
, blocknr
, blocksize
);
432 uptodate
= btrfs_buffer_uptodate(cur
, gen
);
435 if (!cur
|| !uptodate
) {
437 free_extent_buffer(cur
);
441 cur
= read_tree_block(root
, blocknr
,
443 } else if (!uptodate
) {
444 btrfs_read_buffer(cur
, gen
);
447 if (search_start
== 0)
448 search_start
= last_block
;
450 btrfs_tree_lock(cur
);
451 err
= __btrfs_cow_block(trans
, root
, cur
, parent
, i
,
454 (end_slot
- i
) * blocksize
));
456 btrfs_tree_unlock(cur
);
457 free_extent_buffer(cur
);
460 search_start
= cur
->start
;
461 last_block
= cur
->start
;
462 *last_ret
= search_start
;
463 btrfs_tree_unlock(cur
);
464 free_extent_buffer(cur
);
466 if (parent
->map_token
) {
467 unmap_extent_buffer(parent
, parent
->map_token
,
469 parent
->map_token
= NULL
;
475 * The leaf data grows from end-to-front in the node.
476 * this returns the address of the start of the last item,
477 * which is the stop of the leaf data stack
479 static inline unsigned int leaf_data_end(struct btrfs_root
*root
,
480 struct extent_buffer
*leaf
)
482 u32 nr
= btrfs_header_nritems(leaf
);
484 return BTRFS_LEAF_DATA_SIZE(root
);
485 return btrfs_item_offset_nr(leaf
, nr
- 1);
488 static int check_node(struct btrfs_root
*root
, struct btrfs_path
*path
,
491 struct extent_buffer
*parent
= NULL
;
492 struct extent_buffer
*node
= path
->nodes
[level
];
493 struct btrfs_disk_key parent_key
;
494 struct btrfs_disk_key node_key
;
497 struct btrfs_key cpukey
;
498 u32 nritems
= btrfs_header_nritems(node
);
500 if (path
->nodes
[level
+ 1])
501 parent
= path
->nodes
[level
+ 1];
503 slot
= path
->slots
[level
];
504 BUG_ON(nritems
== 0);
506 parent_slot
= path
->slots
[level
+ 1];
507 btrfs_node_key(parent
, &parent_key
, parent_slot
);
508 btrfs_node_key(node
, &node_key
, 0);
509 BUG_ON(memcmp(&parent_key
, &node_key
,
510 sizeof(struct btrfs_disk_key
)));
511 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
512 btrfs_header_bytenr(node
));
514 BUG_ON(nritems
> BTRFS_NODEPTRS_PER_BLOCK(root
));
516 btrfs_node_key_to_cpu(node
, &cpukey
, slot
- 1);
517 btrfs_node_key(node
, &node_key
, slot
);
518 BUG_ON(comp_keys(&node_key
, &cpukey
) <= 0);
520 if (slot
< nritems
- 1) {
521 btrfs_node_key_to_cpu(node
, &cpukey
, slot
+ 1);
522 btrfs_node_key(node
, &node_key
, slot
);
523 BUG_ON(comp_keys(&node_key
, &cpukey
) >= 0);
528 static int check_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
,
531 struct extent_buffer
*leaf
= path
->nodes
[level
];
532 struct extent_buffer
*parent
= NULL
;
534 struct btrfs_key cpukey
;
535 struct btrfs_disk_key parent_key
;
536 struct btrfs_disk_key leaf_key
;
537 int slot
= path
->slots
[0];
539 u32 nritems
= btrfs_header_nritems(leaf
);
541 if (path
->nodes
[level
+ 1])
542 parent
= path
->nodes
[level
+ 1];
548 parent_slot
= path
->slots
[level
+ 1];
549 btrfs_node_key(parent
, &parent_key
, parent_slot
);
550 btrfs_item_key(leaf
, &leaf_key
, 0);
552 BUG_ON(memcmp(&parent_key
, &leaf_key
,
553 sizeof(struct btrfs_disk_key
)));
554 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
555 btrfs_header_bytenr(leaf
));
558 for (i
= 0; nritems
> 1 && i
< nritems
- 2; i
++) {
559 btrfs_item_key_to_cpu(leaf
, &cpukey
, i
+ 1);
560 btrfs_item_key(leaf
, &leaf_key
, i
);
561 if (comp_keys(&leaf_key
, &cpukey
) >= 0) {
562 btrfs_print_leaf(root
, leaf
);
563 printk("slot %d offset bad key\n", i
);
566 if (btrfs_item_offset_nr(leaf
, i
) !=
567 btrfs_item_end_nr(leaf
, i
+ 1)) {
568 btrfs_print_leaf(root
, leaf
);
569 printk("slot %d offset bad\n", i
);
573 if (btrfs_item_offset_nr(leaf
, i
) +
574 btrfs_item_size_nr(leaf
, i
) !=
575 BTRFS_LEAF_DATA_SIZE(root
)) {
576 btrfs_print_leaf(root
, leaf
);
577 printk("slot %d first offset bad\n", i
);
583 if (btrfs_item_size_nr(leaf
, nritems
- 1) > 4096) {
584 btrfs_print_leaf(root
, leaf
);
585 printk("slot %d bad size \n", nritems
- 1);
590 if (slot
!= 0 && slot
< nritems
- 1) {
591 btrfs_item_key(leaf
, &leaf_key
, slot
);
592 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
- 1);
593 if (comp_keys(&leaf_key
, &cpukey
) <= 0) {
594 btrfs_print_leaf(root
, leaf
);
595 printk("slot %d offset bad key\n", slot
);
598 if (btrfs_item_offset_nr(leaf
, slot
- 1) !=
599 btrfs_item_end_nr(leaf
, slot
)) {
600 btrfs_print_leaf(root
, leaf
);
601 printk("slot %d offset bad\n", slot
);
605 if (slot
< nritems
- 1) {
606 btrfs_item_key(leaf
, &leaf_key
, slot
);
607 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
+ 1);
608 BUG_ON(comp_keys(&leaf_key
, &cpukey
) >= 0);
609 if (btrfs_item_offset_nr(leaf
, slot
) !=
610 btrfs_item_end_nr(leaf
, slot
+ 1)) {
611 btrfs_print_leaf(root
, leaf
);
612 printk("slot %d offset bad\n", slot
);
616 BUG_ON(btrfs_item_offset_nr(leaf
, 0) +
617 btrfs_item_size_nr(leaf
, 0) != BTRFS_LEAF_DATA_SIZE(root
));
621 static int noinline
check_block(struct btrfs_root
*root
,
622 struct btrfs_path
*path
, int level
)
626 if (btrfs_header_level(path
->nodes
[level
]) != level
)
627 printk("warning: bad level %Lu wanted %d found %d\n",
628 path
->nodes
[level
]->start
, level
,
629 btrfs_header_level(path
->nodes
[level
]));
630 found_start
= btrfs_header_bytenr(path
->nodes
[level
]);
631 if (found_start
!= path
->nodes
[level
]->start
) {
632 printk("warning: bad bytentr %Lu found %Lu\n",
633 path
->nodes
[level
]->start
, found_start
);
636 struct extent_buffer
*buf
= path
->nodes
[level
];
638 if (memcmp_extent_buffer(buf
, root
->fs_info
->fsid
,
639 (unsigned long)btrfs_header_fsid(buf
),
641 printk("warning bad block %Lu\n", buf
->start
);
646 return check_leaf(root
, path
, level
);
647 return check_node(root
, path
, level
);
651 * search for key in the extent_buffer. The items start at offset p,
652 * and they are item_size apart. There are 'max' items in p.
654 * the slot in the array is returned via slot, and it points to
655 * the place where you would insert key if it is not found in
658 * slot may point to max if the key is bigger than all of the keys
660 static int generic_bin_search(struct extent_buffer
*eb
, unsigned long p
,
661 int item_size
, struct btrfs_key
*key
,
668 struct btrfs_disk_key
*tmp
= NULL
;
669 struct btrfs_disk_key unaligned
;
670 unsigned long offset
;
671 char *map_token
= NULL
;
673 unsigned long map_start
= 0;
674 unsigned long map_len
= 0;
678 mid
= (low
+ high
) / 2;
679 offset
= p
+ mid
* item_size
;
681 if (!map_token
|| offset
< map_start
||
682 (offset
+ sizeof(struct btrfs_disk_key
)) >
683 map_start
+ map_len
) {
685 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
688 err
= map_extent_buffer(eb
, offset
,
689 sizeof(struct btrfs_disk_key
),
691 &map_start
, &map_len
, KM_USER0
);
694 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
697 read_extent_buffer(eb
, &unaligned
,
698 offset
, sizeof(unaligned
));
703 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
706 ret
= comp_keys(tmp
, key
);
715 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
721 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
726 * simple bin_search frontend that does the right thing for
729 static int bin_search(struct extent_buffer
*eb
, struct btrfs_key
*key
,
730 int level
, int *slot
)
733 return generic_bin_search(eb
,
734 offsetof(struct btrfs_leaf
, items
),
735 sizeof(struct btrfs_item
),
736 key
, btrfs_header_nritems(eb
),
739 return generic_bin_search(eb
,
740 offsetof(struct btrfs_node
, ptrs
),
741 sizeof(struct btrfs_key_ptr
),
742 key
, btrfs_header_nritems(eb
),
748 static struct extent_buffer
*read_node_slot(struct btrfs_root
*root
,
749 struct extent_buffer
*parent
, int slot
)
751 int level
= btrfs_header_level(parent
);
754 if (slot
>= btrfs_header_nritems(parent
))
759 return read_tree_block(root
, btrfs_node_blockptr(parent
, slot
),
760 btrfs_level_size(root
, level
- 1),
761 btrfs_node_ptr_generation(parent
, slot
));
764 static int balance_level(struct btrfs_trans_handle
*trans
,
765 struct btrfs_root
*root
,
766 struct btrfs_path
*path
, int level
)
768 struct extent_buffer
*right
= NULL
;
769 struct extent_buffer
*mid
;
770 struct extent_buffer
*left
= NULL
;
771 struct extent_buffer
*parent
= NULL
;
775 int orig_slot
= path
->slots
[level
];
776 int err_on_enospc
= 0;
782 mid
= path
->nodes
[level
];
783 WARN_ON(!path
->locks
[level
]);
784 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
786 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
788 if (level
< BTRFS_MAX_LEVEL
- 1)
789 parent
= path
->nodes
[level
+ 1];
790 pslot
= path
->slots
[level
+ 1];
793 * deal with the case where there is only one pointer in the root
794 * by promoting the node below to a root
797 struct extent_buffer
*child
;
799 if (btrfs_header_nritems(mid
) != 1)
802 /* promote the child to a root */
803 child
= read_node_slot(root
, mid
, 0);
804 btrfs_tree_lock(child
);
806 ret
= btrfs_cow_block(trans
, root
, child
, mid
, 0, &child
);
809 spin_lock(&root
->node_lock
);
811 spin_unlock(&root
->node_lock
);
813 add_root_to_dirty_list(root
);
814 btrfs_tree_unlock(child
);
815 path
->locks
[level
] = 0;
816 path
->nodes
[level
] = NULL
;
817 clean_tree_block(trans
, root
, mid
);
818 btrfs_tree_unlock(mid
);
819 /* once for the path */
820 free_extent_buffer(mid
);
821 ret
= btrfs_free_extent(trans
, root
, mid
->start
, mid
->len
,
822 root
->root_key
.objectid
,
823 btrfs_header_generation(mid
), 0, 0, 1);
824 /* once for the root ptr */
825 free_extent_buffer(mid
);
828 if (btrfs_header_nritems(mid
) >
829 BTRFS_NODEPTRS_PER_BLOCK(root
) / 4)
832 if (btrfs_header_nritems(mid
) < 2)
835 left
= read_node_slot(root
, parent
, pslot
- 1);
837 btrfs_tree_lock(left
);
838 wret
= btrfs_cow_block(trans
, root
, left
,
839 parent
, pslot
- 1, &left
);
845 right
= read_node_slot(root
, parent
, pslot
+ 1);
847 btrfs_tree_lock(right
);
848 wret
= btrfs_cow_block(trans
, root
, right
,
849 parent
, pslot
+ 1, &right
);
856 /* first, try to make some room in the middle buffer */
858 orig_slot
+= btrfs_header_nritems(left
);
859 wret
= push_node_left(trans
, root
, left
, mid
, 1);
862 if (btrfs_header_nritems(mid
) < 2)
867 * then try to empty the right most buffer into the middle
870 wret
= push_node_left(trans
, root
, mid
, right
, 1);
871 if (wret
< 0 && wret
!= -ENOSPC
)
873 if (btrfs_header_nritems(right
) == 0) {
874 u64 bytenr
= right
->start
;
875 u64 generation
= btrfs_header_generation(parent
);
876 u32 blocksize
= right
->len
;
878 clean_tree_block(trans
, root
, right
);
879 btrfs_tree_unlock(right
);
880 free_extent_buffer(right
);
882 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
+
886 wret
= btrfs_free_extent(trans
, root
, bytenr
,
888 btrfs_header_owner(parent
),
889 generation
, 0, 0, 1);
893 struct btrfs_disk_key right_key
;
894 btrfs_node_key(right
, &right_key
, 0);
895 btrfs_set_node_key(parent
, &right_key
, pslot
+ 1);
896 btrfs_mark_buffer_dirty(parent
);
899 if (btrfs_header_nritems(mid
) == 1) {
901 * we're not allowed to leave a node with one item in the
902 * tree during a delete. A deletion from lower in the tree
903 * could try to delete the only pointer in this node.
904 * So, pull some keys from the left.
905 * There has to be a left pointer at this point because
906 * otherwise we would have pulled some pointers from the
910 wret
= balance_node_right(trans
, root
, mid
, left
);
916 wret
= push_node_left(trans
, root
, left
, mid
, 1);
922 if (btrfs_header_nritems(mid
) == 0) {
923 /* we've managed to empty the middle node, drop it */
924 u64 root_gen
= btrfs_header_generation(parent
);
925 u64 bytenr
= mid
->start
;
926 u32 blocksize
= mid
->len
;
928 clean_tree_block(trans
, root
, mid
);
929 btrfs_tree_unlock(mid
);
930 free_extent_buffer(mid
);
932 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
);
935 wret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
,
936 btrfs_header_owner(parent
),
941 /* update the parent key to reflect our changes */
942 struct btrfs_disk_key mid_key
;
943 btrfs_node_key(mid
, &mid_key
, 0);
944 btrfs_set_node_key(parent
, &mid_key
, pslot
);
945 btrfs_mark_buffer_dirty(parent
);
948 /* update the path */
950 if (btrfs_header_nritems(left
) > orig_slot
) {
951 extent_buffer_get(left
);
952 /* left was locked after cow */
953 path
->nodes
[level
] = left
;
954 path
->slots
[level
+ 1] -= 1;
955 path
->slots
[level
] = orig_slot
;
957 btrfs_tree_unlock(mid
);
958 free_extent_buffer(mid
);
961 orig_slot
-= btrfs_header_nritems(left
);
962 path
->slots
[level
] = orig_slot
;
965 /* double check we haven't messed things up */
966 check_block(root
, path
, level
);
968 btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]))
972 btrfs_tree_unlock(right
);
973 free_extent_buffer(right
);
976 if (path
->nodes
[level
] != left
)
977 btrfs_tree_unlock(left
);
978 free_extent_buffer(left
);
983 /* returns zero if the push worked, non-zero otherwise */
984 static int noinline
push_nodes_for_insert(struct btrfs_trans_handle
*trans
,
985 struct btrfs_root
*root
,
986 struct btrfs_path
*path
, int level
)
988 struct extent_buffer
*right
= NULL
;
989 struct extent_buffer
*mid
;
990 struct extent_buffer
*left
= NULL
;
991 struct extent_buffer
*parent
= NULL
;
995 int orig_slot
= path
->slots
[level
];
1001 mid
= path
->nodes
[level
];
1002 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
1003 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
1005 if (level
< BTRFS_MAX_LEVEL
- 1)
1006 parent
= path
->nodes
[level
+ 1];
1007 pslot
= path
->slots
[level
+ 1];
1012 left
= read_node_slot(root
, parent
, pslot
- 1);
1014 /* first, try to make some room in the middle buffer */
1018 btrfs_tree_lock(left
);
1019 left_nr
= btrfs_header_nritems(left
);
1020 if (left_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
1023 ret
= btrfs_cow_block(trans
, root
, left
, parent
,
1028 wret
= push_node_left(trans
, root
,
1035 struct btrfs_disk_key disk_key
;
1036 orig_slot
+= left_nr
;
1037 btrfs_node_key(mid
, &disk_key
, 0);
1038 btrfs_set_node_key(parent
, &disk_key
, pslot
);
1039 btrfs_mark_buffer_dirty(parent
);
1040 if (btrfs_header_nritems(left
) > orig_slot
) {
1041 path
->nodes
[level
] = left
;
1042 path
->slots
[level
+ 1] -= 1;
1043 path
->slots
[level
] = orig_slot
;
1044 btrfs_tree_unlock(mid
);
1045 free_extent_buffer(mid
);
1048 btrfs_header_nritems(left
);
1049 path
->slots
[level
] = orig_slot
;
1050 btrfs_tree_unlock(left
);
1051 free_extent_buffer(left
);
1055 btrfs_tree_unlock(left
);
1056 free_extent_buffer(left
);
1058 right
= read_node_slot(root
, parent
, pslot
+ 1);
1061 * then try to empty the right most buffer into the middle
1065 btrfs_tree_lock(right
);
1066 right_nr
= btrfs_header_nritems(right
);
1067 if (right_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
1070 ret
= btrfs_cow_block(trans
, root
, right
,
1076 wret
= balance_node_right(trans
, root
,
1083 struct btrfs_disk_key disk_key
;
1085 btrfs_node_key(right
, &disk_key
, 0);
1086 btrfs_set_node_key(parent
, &disk_key
, pslot
+ 1);
1087 btrfs_mark_buffer_dirty(parent
);
1089 if (btrfs_header_nritems(mid
) <= orig_slot
) {
1090 path
->nodes
[level
] = right
;
1091 path
->slots
[level
+ 1] += 1;
1092 path
->slots
[level
] = orig_slot
-
1093 btrfs_header_nritems(mid
);
1094 btrfs_tree_unlock(mid
);
1095 free_extent_buffer(mid
);
1097 btrfs_tree_unlock(right
);
1098 free_extent_buffer(right
);
1102 btrfs_tree_unlock(right
);
1103 free_extent_buffer(right
);
1109 * readahead one full node of leaves
1111 static void reada_for_search(struct btrfs_root
*root
, struct btrfs_path
*path
,
1112 int level
, int slot
, u64 objectid
)
1114 struct extent_buffer
*node
;
1115 struct btrfs_disk_key disk_key
;
1121 int direction
= path
->reada
;
1122 struct extent_buffer
*eb
;
1130 if (!path
->nodes
[level
])
1133 node
= path
->nodes
[level
];
1135 search
= btrfs_node_blockptr(node
, slot
);
1136 blocksize
= btrfs_level_size(root
, level
- 1);
1137 eb
= btrfs_find_tree_block(root
, search
, blocksize
);
1139 free_extent_buffer(eb
);
1143 highest_read
= search
;
1144 lowest_read
= search
;
1146 nritems
= btrfs_header_nritems(node
);
1149 if (direction
< 0) {
1153 } else if (direction
> 0) {
1158 if (path
->reada
< 0 && objectid
) {
1159 btrfs_node_key(node
, &disk_key
, nr
);
1160 if (btrfs_disk_key_objectid(&disk_key
) != objectid
)
1163 search
= btrfs_node_blockptr(node
, nr
);
1164 if ((search
>= lowest_read
&& search
<= highest_read
) ||
1165 (search
< lowest_read
&& lowest_read
- search
<= 32768) ||
1166 (search
> highest_read
&& search
- highest_read
<= 32768)) {
1167 readahead_tree_block(root
, search
, blocksize
,
1168 btrfs_node_ptr_generation(node
, nr
));
1172 if (path
->reada
< 2 && (nread
> (256 * 1024) || nscan
> 32))
1174 if(nread
> (1024 * 1024) || nscan
> 128)
1177 if (search
< lowest_read
)
1178 lowest_read
= search
;
1179 if (search
> highest_read
)
1180 highest_read
= search
;
1184 static void unlock_up(struct btrfs_path
*path
, int level
, int lowest_unlock
)
1187 int skip_level
= level
;
1189 struct extent_buffer
*t
;
1191 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1192 if (!path
->nodes
[i
])
1194 if (!path
->locks
[i
])
1196 if (!no_skips
&& path
->slots
[i
] == 0) {
1200 if (!no_skips
&& path
->keep_locks
) {
1203 nritems
= btrfs_header_nritems(t
);
1204 if (nritems
< 1 || path
->slots
[i
] >= nritems
- 1) {
1209 if (skip_level
< i
&& i
>= lowest_unlock
)
1213 if (i
>= lowest_unlock
&& i
> skip_level
&& path
->locks
[i
]) {
1214 btrfs_tree_unlock(t
);
1221 * look for key in the tree. path is filled in with nodes along the way
1222 * if key is found, we return zero and you can find the item in the leaf
1223 * level of the path (level 0)
1225 * If the key isn't found, the path points to the slot where it should
1226 * be inserted, and 1 is returned. If there are other errors during the
1227 * search a negative error number is returned.
1229 * if ins_len > 0, nodes and leaves will be split as we walk down the
1230 * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
1233 int btrfs_search_slot(struct btrfs_trans_handle
*trans
, struct btrfs_root
1234 *root
, struct btrfs_key
*key
, struct btrfs_path
*p
, int
1237 struct extent_buffer
*b
;
1238 struct extent_buffer
*tmp
;
1242 int should_reada
= p
->reada
;
1243 int lowest_unlock
= 1;
1245 u8 lowest_level
= 0;
1249 lowest_level
= p
->lowest_level
;
1250 WARN_ON(lowest_level
&& ins_len
);
1251 WARN_ON(p
->nodes
[0] != NULL
);
1252 WARN_ON(cow
&& root
== root
->fs_info
->extent_root
&&
1253 !mutex_is_locked(&root
->fs_info
->alloc_mutex
));
1257 if (p
->skip_locking
)
1258 b
= btrfs_root_node(root
);
1260 b
= btrfs_lock_root_node(root
);
1263 level
= btrfs_header_level(b
);
1266 wret
= btrfs_cow_block(trans
, root
, b
,
1267 p
->nodes
[level
+ 1],
1268 p
->slots
[level
+ 1],
1271 free_extent_buffer(b
);
1275 BUG_ON(!cow
&& ins_len
);
1276 if (level
!= btrfs_header_level(b
))
1278 level
= btrfs_header_level(b
);
1279 p
->nodes
[level
] = b
;
1280 if (!p
->skip_locking
)
1281 p
->locks
[level
] = 1;
1282 ret
= check_block(root
, p
, level
);
1286 ret
= bin_search(b
, key
, level
, &slot
);
1288 if (ret
&& slot
> 0)
1290 p
->slots
[level
] = slot
;
1291 if (ins_len
> 0 && btrfs_header_nritems(b
) >=
1292 BTRFS_NODEPTRS_PER_BLOCK(root
) - 3) {
1293 int sret
= split_node(trans
, root
, p
, level
);
1297 b
= p
->nodes
[level
];
1298 slot
= p
->slots
[level
];
1299 } else if (ins_len
< 0) {
1300 int sret
= balance_level(trans
, root
, p
,
1304 b
= p
->nodes
[level
];
1306 btrfs_release_path(NULL
, p
);
1309 slot
= p
->slots
[level
];
1310 BUG_ON(btrfs_header_nritems(b
) == 1);
1312 unlock_up(p
, level
, lowest_unlock
);
1314 /* this is only true while dropping a snapshot */
1315 if (level
== lowest_level
) {
1319 blocknr
= btrfs_node_blockptr(b
, slot
);
1320 gen
= btrfs_node_ptr_generation(b
, slot
);
1321 blocksize
= btrfs_level_size(root
, level
- 1);
1323 tmp
= btrfs_find_tree_block(root
, blocknr
, blocksize
);
1324 if (tmp
&& btrfs_buffer_uptodate(tmp
, gen
)) {
1328 * reduce lock contention at high levels
1329 * of the btree by dropping locks before
1333 btrfs_release_path(NULL
, p
);
1335 free_extent_buffer(tmp
);
1337 reada_for_search(root
, p
,
1341 tmp
= read_tree_block(root
, blocknr
,
1344 free_extent_buffer(tmp
);
1348 free_extent_buffer(tmp
);
1350 reada_for_search(root
, p
,
1353 b
= read_node_slot(root
, b
, slot
);
1356 if (!p
->skip_locking
)
1359 p
->slots
[level
] = slot
;
1360 if (ins_len
> 0 && btrfs_leaf_free_space(root
, b
) <
1361 sizeof(struct btrfs_item
) + ins_len
) {
1362 int sret
= split_leaf(trans
, root
, key
,
1363 p
, ins_len
, ret
== 0);
1368 unlock_up(p
, level
, lowest_unlock
);
1376 * adjust the pointers going up the tree, starting at level
1377 * making sure the right key of each node is points to 'key'.
1378 * This is used after shifting pointers to the left, so it stops
1379 * fixing up pointers when a given leaf/node is not in slot 0 of the
1382 * If this fails to write a tree block, it returns -1, but continues
1383 * fixing up the blocks in ram so the tree is consistent.
1385 static int fixup_low_keys(struct btrfs_trans_handle
*trans
,
1386 struct btrfs_root
*root
, struct btrfs_path
*path
,
1387 struct btrfs_disk_key
*key
, int level
)
1391 struct extent_buffer
*t
;
1393 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1394 int tslot
= path
->slots
[i
];
1395 if (!path
->nodes
[i
])
1398 btrfs_set_node_key(t
, key
, tslot
);
1399 btrfs_mark_buffer_dirty(path
->nodes
[i
]);
1407 * try to push data from one node into the next node left in the
1410 * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
1411 * error, and > 0 if there was no room in the left hand block.
1413 static int push_node_left(struct btrfs_trans_handle
*trans
,
1414 struct btrfs_root
*root
, struct extent_buffer
*dst
,
1415 struct extent_buffer
*src
, int empty
)
1422 src_nritems
= btrfs_header_nritems(src
);
1423 dst_nritems
= btrfs_header_nritems(dst
);
1424 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1425 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1426 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1428 if (!empty
&& src_nritems
<= 8)
1431 if (push_items
<= 0) {
1436 push_items
= min(src_nritems
, push_items
);
1437 if (push_items
< src_nritems
) {
1438 /* leave at least 8 pointers in the node if
1439 * we aren't going to empty it
1441 if (src_nritems
- push_items
< 8) {
1442 if (push_items
<= 8)
1448 push_items
= min(src_nritems
- 8, push_items
);
1450 copy_extent_buffer(dst
, src
,
1451 btrfs_node_key_ptr_offset(dst_nritems
),
1452 btrfs_node_key_ptr_offset(0),
1453 push_items
* sizeof(struct btrfs_key_ptr
));
1455 if (push_items
< src_nritems
) {
1456 memmove_extent_buffer(src
, btrfs_node_key_ptr_offset(0),
1457 btrfs_node_key_ptr_offset(push_items
),
1458 (src_nritems
- push_items
) *
1459 sizeof(struct btrfs_key_ptr
));
1461 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1462 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1463 btrfs_mark_buffer_dirty(src
);
1464 btrfs_mark_buffer_dirty(dst
);
1469 * try to push data from one node into the next node right in the
1472 * returns 0 if some ptrs were pushed, < 0 if there was some horrible
1473 * error, and > 0 if there was no room in the right hand block.
1475 * this will only push up to 1/2 the contents of the left node over
1477 static int balance_node_right(struct btrfs_trans_handle
*trans
,
1478 struct btrfs_root
*root
,
1479 struct extent_buffer
*dst
,
1480 struct extent_buffer
*src
)
1488 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1489 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1491 src_nritems
= btrfs_header_nritems(src
);
1492 dst_nritems
= btrfs_header_nritems(dst
);
1493 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1494 if (push_items
<= 0) {
1498 if (src_nritems
< 4) {
1502 max_push
= src_nritems
/ 2 + 1;
1503 /* don't try to empty the node */
1504 if (max_push
>= src_nritems
) {
1508 if (max_push
< push_items
)
1509 push_items
= max_push
;
1511 memmove_extent_buffer(dst
, btrfs_node_key_ptr_offset(push_items
),
1512 btrfs_node_key_ptr_offset(0),
1514 sizeof(struct btrfs_key_ptr
));
1516 copy_extent_buffer(dst
, src
,
1517 btrfs_node_key_ptr_offset(0),
1518 btrfs_node_key_ptr_offset(src_nritems
- push_items
),
1519 push_items
* sizeof(struct btrfs_key_ptr
));
1521 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1522 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1524 btrfs_mark_buffer_dirty(src
);
1525 btrfs_mark_buffer_dirty(dst
);
1530 * helper function to insert a new root level in the tree.
1531 * A new node is allocated, and a single item is inserted to
1532 * point to the existing root
1534 * returns zero on success or < 0 on failure.
1536 static int noinline
insert_new_root(struct btrfs_trans_handle
*trans
,
1537 struct btrfs_root
*root
,
1538 struct btrfs_path
*path
, int level
)
1542 struct extent_buffer
*lower
;
1543 struct extent_buffer
*c
;
1544 struct extent_buffer
*old
;
1545 struct btrfs_disk_key lower_key
;
1547 BUG_ON(path
->nodes
[level
]);
1548 BUG_ON(path
->nodes
[level
-1] != root
->node
);
1551 root_gen
= trans
->transid
;
1555 lower
= path
->nodes
[level
-1];
1557 btrfs_item_key(lower
, &lower_key
, 0);
1559 btrfs_node_key(lower
, &lower_key
, 0);
1561 c
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1562 root
->root_key
.objectid
,
1563 root_gen
, lower_key
.objectid
, level
,
1564 root
->node
->start
, 0);
1568 memset_extent_buffer(c
, 0, 0, root
->nodesize
);
1569 btrfs_set_header_nritems(c
, 1);
1570 btrfs_set_header_level(c
, level
);
1571 btrfs_set_header_bytenr(c
, c
->start
);
1572 btrfs_set_header_generation(c
, trans
->transid
);
1573 btrfs_set_header_owner(c
, root
->root_key
.objectid
);
1575 write_extent_buffer(c
, root
->fs_info
->fsid
,
1576 (unsigned long)btrfs_header_fsid(c
),
1579 write_extent_buffer(c
, root
->fs_info
->chunk_tree_uuid
,
1580 (unsigned long)btrfs_header_chunk_tree_uuid(c
),
1583 btrfs_set_node_key(c
, &lower_key
, 0);
1584 btrfs_set_node_blockptr(c
, 0, lower
->start
);
1585 lower_gen
= btrfs_header_generation(lower
);
1586 WARN_ON(lower_gen
== 0);
1588 btrfs_set_node_ptr_generation(c
, 0, lower_gen
);
1590 btrfs_mark_buffer_dirty(c
);
1592 spin_lock(&root
->node_lock
);
1595 spin_unlock(&root
->node_lock
);
1597 /* the super has an extra ref to root->node */
1598 free_extent_buffer(old
);
1600 add_root_to_dirty_list(root
);
1601 extent_buffer_get(c
);
1602 path
->nodes
[level
] = c
;
1603 path
->locks
[level
] = 1;
1604 path
->slots
[level
] = 0;
1606 if (root
->ref_cows
&& lower_gen
!= trans
->transid
) {
1607 struct btrfs_path
*back_path
= btrfs_alloc_path();
1609 mutex_lock(&root
->fs_info
->alloc_mutex
);
1610 ret
= btrfs_insert_extent_backref(trans
,
1611 root
->fs_info
->extent_root
,
1613 root
->root_key
.objectid
,
1614 trans
->transid
, 0, 0);
1616 mutex_unlock(&root
->fs_info
->alloc_mutex
);
1617 btrfs_free_path(back_path
);
1623 * worker function to insert a single pointer in a node.
1624 * the node should have enough room for the pointer already
1626 * slot and level indicate where you want the key to go, and
1627 * blocknr is the block the key points to.
1629 * returns zero on success and < 0 on any error
1631 static int insert_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
1632 *root
, struct btrfs_path
*path
, struct btrfs_disk_key
1633 *key
, u64 bytenr
, int slot
, int level
)
1635 struct extent_buffer
*lower
;
1638 BUG_ON(!path
->nodes
[level
]);
1639 lower
= path
->nodes
[level
];
1640 nritems
= btrfs_header_nritems(lower
);
1643 if (nritems
== BTRFS_NODEPTRS_PER_BLOCK(root
))
1645 if (slot
!= nritems
) {
1646 memmove_extent_buffer(lower
,
1647 btrfs_node_key_ptr_offset(slot
+ 1),
1648 btrfs_node_key_ptr_offset(slot
),
1649 (nritems
- slot
) * sizeof(struct btrfs_key_ptr
));
1651 btrfs_set_node_key(lower
, key
, slot
);
1652 btrfs_set_node_blockptr(lower
, slot
, bytenr
);
1653 WARN_ON(trans
->transid
== 0);
1654 btrfs_set_node_ptr_generation(lower
, slot
, trans
->transid
);
1655 btrfs_set_header_nritems(lower
, nritems
+ 1);
1656 btrfs_mark_buffer_dirty(lower
);
1661 * split the node at the specified level in path in two.
1662 * The path is corrected to point to the appropriate node after the split
1664 * Before splitting this tries to make some room in the node by pushing
1665 * left and right, if either one works, it returns right away.
1667 * returns 0 on success and < 0 on failure
1669 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
1670 *root
, struct btrfs_path
*path
, int level
)
1673 struct extent_buffer
*c
;
1674 struct extent_buffer
*split
;
1675 struct btrfs_disk_key disk_key
;
1681 c
= path
->nodes
[level
];
1682 WARN_ON(btrfs_header_generation(c
) != trans
->transid
);
1683 if (c
== root
->node
) {
1684 /* trying to split the root, lets make a new one */
1685 ret
= insert_new_root(trans
, root
, path
, level
+ 1);
1689 ret
= push_nodes_for_insert(trans
, root
, path
, level
);
1690 c
= path
->nodes
[level
];
1691 if (!ret
&& btrfs_header_nritems(c
) <
1692 BTRFS_NODEPTRS_PER_BLOCK(root
) - 3)
1698 c_nritems
= btrfs_header_nritems(c
);
1700 root_gen
= trans
->transid
;
1704 btrfs_node_key(c
, &disk_key
, 0);
1705 split
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1706 root
->root_key
.objectid
,
1708 btrfs_disk_key_objectid(&disk_key
),
1709 level
, c
->start
, 0);
1711 return PTR_ERR(split
);
1713 btrfs_set_header_flags(split
, btrfs_header_flags(c
));
1714 btrfs_set_header_level(split
, btrfs_header_level(c
));
1715 btrfs_set_header_bytenr(split
, split
->start
);
1716 btrfs_set_header_generation(split
, trans
->transid
);
1717 btrfs_set_header_owner(split
, root
->root_key
.objectid
);
1718 btrfs_set_header_flags(split
, 0);
1719 write_extent_buffer(split
, root
->fs_info
->fsid
,
1720 (unsigned long)btrfs_header_fsid(split
),
1722 write_extent_buffer(split
, root
->fs_info
->chunk_tree_uuid
,
1723 (unsigned long)btrfs_header_chunk_tree_uuid(split
),
1726 mid
= (c_nritems
+ 1) / 2;
1728 copy_extent_buffer(split
, c
,
1729 btrfs_node_key_ptr_offset(0),
1730 btrfs_node_key_ptr_offset(mid
),
1731 (c_nritems
- mid
) * sizeof(struct btrfs_key_ptr
));
1732 btrfs_set_header_nritems(split
, c_nritems
- mid
);
1733 btrfs_set_header_nritems(c
, mid
);
1736 btrfs_mark_buffer_dirty(c
);
1737 btrfs_mark_buffer_dirty(split
);
1739 btrfs_node_key(split
, &disk_key
, 0);
1740 wret
= insert_ptr(trans
, root
, path
, &disk_key
, split
->start
,
1741 path
->slots
[level
+ 1] + 1,
1746 if (path
->slots
[level
] >= mid
) {
1747 path
->slots
[level
] -= mid
;
1748 btrfs_tree_unlock(c
);
1749 free_extent_buffer(c
);
1750 path
->nodes
[level
] = split
;
1751 path
->slots
[level
+ 1] += 1;
1753 btrfs_tree_unlock(split
);
1754 free_extent_buffer(split
);
1760 * how many bytes are required to store the items in a leaf. start
1761 * and nr indicate which items in the leaf to check. This totals up the
1762 * space used both by the item structs and the item data
1764 static int leaf_space_used(struct extent_buffer
*l
, int start
, int nr
)
1767 int nritems
= btrfs_header_nritems(l
);
1768 int end
= min(nritems
, start
+ nr
) - 1;
1772 data_len
= btrfs_item_end_nr(l
, start
);
1773 data_len
= data_len
- btrfs_item_offset_nr(l
, end
);
1774 data_len
+= sizeof(struct btrfs_item
) * nr
;
1775 WARN_ON(data_len
< 0);
1780 * The space between the end of the leaf items and
1781 * the start of the leaf data. IOW, how much room
1782 * the leaf has left for both items and data
1784 int btrfs_leaf_free_space(struct btrfs_root
*root
, struct extent_buffer
*leaf
)
1786 int nritems
= btrfs_header_nritems(leaf
);
1788 ret
= BTRFS_LEAF_DATA_SIZE(root
) - leaf_space_used(leaf
, 0, nritems
);
1790 printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
1791 ret
, (unsigned long) BTRFS_LEAF_DATA_SIZE(root
),
1792 leaf_space_used(leaf
, 0, nritems
), nritems
);
1798 * push some data in the path leaf to the right, trying to free up at
1799 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1801 * returns 1 if the push failed because the other node didn't have enough
1802 * room, 0 if everything worked out and < 0 if there were major errors.
1804 static int push_leaf_right(struct btrfs_trans_handle
*trans
, struct btrfs_root
1805 *root
, struct btrfs_path
*path
, int data_size
,
1808 struct extent_buffer
*left
= path
->nodes
[0];
1809 struct extent_buffer
*right
;
1810 struct extent_buffer
*upper
;
1811 struct btrfs_disk_key disk_key
;
1817 struct btrfs_item
*item
;
1825 slot
= path
->slots
[1];
1826 if (!path
->nodes
[1]) {
1829 upper
= path
->nodes
[1];
1830 if (slot
>= btrfs_header_nritems(upper
) - 1)
1833 WARN_ON(!btrfs_tree_locked(path
->nodes
[1]));
1835 right
= read_node_slot(root
, upper
, slot
+ 1);
1836 btrfs_tree_lock(right
);
1837 free_space
= btrfs_leaf_free_space(root
, right
);
1838 if (free_space
< data_size
+ sizeof(struct btrfs_item
))
1841 /* cow and double check */
1842 ret
= btrfs_cow_block(trans
, root
, right
, upper
,
1847 free_space
= btrfs_leaf_free_space(root
, right
);
1848 if (free_space
< data_size
+ sizeof(struct btrfs_item
))
1851 left_nritems
= btrfs_header_nritems(left
);
1852 if (left_nritems
== 0)
1860 i
= left_nritems
- 1;
1862 item
= btrfs_item_nr(left
, i
);
1864 if (path
->slots
[0] == i
)
1865 push_space
+= data_size
+ sizeof(*item
);
1867 if (!left
->map_token
) {
1868 map_extent_buffer(left
, (unsigned long)item
,
1869 sizeof(struct btrfs_item
),
1870 &left
->map_token
, &left
->kaddr
,
1871 &left
->map_start
, &left
->map_len
,
1875 this_item_size
= btrfs_item_size(left
, item
);
1876 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1879 push_space
+= this_item_size
+ sizeof(*item
);
1884 if (left
->map_token
) {
1885 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1886 left
->map_token
= NULL
;
1889 if (push_items
== 0)
1892 if (!empty
&& push_items
== left_nritems
)
1895 /* push left to right */
1896 right_nritems
= btrfs_header_nritems(right
);
1898 push_space
= btrfs_item_end_nr(left
, left_nritems
- push_items
);
1899 push_space
-= leaf_data_end(root
, left
);
1901 /* make room in the right data area */
1902 data_end
= leaf_data_end(root
, right
);
1903 memmove_extent_buffer(right
,
1904 btrfs_leaf_data(right
) + data_end
- push_space
,
1905 btrfs_leaf_data(right
) + data_end
,
1906 BTRFS_LEAF_DATA_SIZE(root
) - data_end
);
1908 /* copy from the left data area */
1909 copy_extent_buffer(right
, left
, btrfs_leaf_data(right
) +
1910 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1911 btrfs_leaf_data(left
) + leaf_data_end(root
, left
),
1914 memmove_extent_buffer(right
, btrfs_item_nr_offset(push_items
),
1915 btrfs_item_nr_offset(0),
1916 right_nritems
* sizeof(struct btrfs_item
));
1918 /* copy the items from left to right */
1919 copy_extent_buffer(right
, left
, btrfs_item_nr_offset(0),
1920 btrfs_item_nr_offset(left_nritems
- push_items
),
1921 push_items
* sizeof(struct btrfs_item
));
1923 /* update the item pointers */
1924 right_nritems
+= push_items
;
1925 btrfs_set_header_nritems(right
, right_nritems
);
1926 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1927 for (i
= 0; i
< right_nritems
; i
++) {
1928 item
= btrfs_item_nr(right
, i
);
1929 if (!right
->map_token
) {
1930 map_extent_buffer(right
, (unsigned long)item
,
1931 sizeof(struct btrfs_item
),
1932 &right
->map_token
, &right
->kaddr
,
1933 &right
->map_start
, &right
->map_len
,
1936 push_space
-= btrfs_item_size(right
, item
);
1937 btrfs_set_item_offset(right
, item
, push_space
);
1940 if (right
->map_token
) {
1941 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1942 right
->map_token
= NULL
;
1944 left_nritems
-= push_items
;
1945 btrfs_set_header_nritems(left
, left_nritems
);
1948 btrfs_mark_buffer_dirty(left
);
1949 btrfs_mark_buffer_dirty(right
);
1951 btrfs_item_key(right
, &disk_key
, 0);
1952 btrfs_set_node_key(upper
, &disk_key
, slot
+ 1);
1953 btrfs_mark_buffer_dirty(upper
);
1955 /* then fixup the leaf pointer in the path */
1956 if (path
->slots
[0] >= left_nritems
) {
1957 path
->slots
[0] -= left_nritems
;
1958 if (btrfs_header_nritems(path
->nodes
[0]) == 0)
1959 clean_tree_block(trans
, root
, path
->nodes
[0]);
1960 btrfs_tree_unlock(path
->nodes
[0]);
1961 free_extent_buffer(path
->nodes
[0]);
1962 path
->nodes
[0] = right
;
1963 path
->slots
[1] += 1;
1965 btrfs_tree_unlock(right
);
1966 free_extent_buffer(right
);
1971 btrfs_tree_unlock(right
);
1972 free_extent_buffer(right
);
1977 * push some data in the path leaf to the left, trying to free up at
1978 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1980 static int push_leaf_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1981 *root
, struct btrfs_path
*path
, int data_size
,
1984 struct btrfs_disk_key disk_key
;
1985 struct extent_buffer
*right
= path
->nodes
[0];
1986 struct extent_buffer
*left
;
1992 struct btrfs_item
*item
;
1993 u32 old_left_nritems
;
1999 u32 old_left_item_size
;
2001 slot
= path
->slots
[1];
2004 if (!path
->nodes
[1])
2007 right_nritems
= btrfs_header_nritems(right
);
2008 if (right_nritems
== 0) {
2012 WARN_ON(!btrfs_tree_locked(path
->nodes
[1]));
2014 left
= read_node_slot(root
, path
->nodes
[1], slot
- 1);
2015 btrfs_tree_lock(left
);
2016 free_space
= btrfs_leaf_free_space(root
, left
);
2017 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
2022 /* cow and double check */
2023 ret
= btrfs_cow_block(trans
, root
, left
,
2024 path
->nodes
[1], slot
- 1, &left
);
2026 /* we hit -ENOSPC, but it isn't fatal here */
2031 free_space
= btrfs_leaf_free_space(root
, left
);
2032 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
2040 nr
= right_nritems
- 1;
2042 for (i
= 0; i
< nr
; i
++) {
2043 item
= btrfs_item_nr(right
, i
);
2044 if (!right
->map_token
) {
2045 map_extent_buffer(right
, (unsigned long)item
,
2046 sizeof(struct btrfs_item
),
2047 &right
->map_token
, &right
->kaddr
,
2048 &right
->map_start
, &right
->map_len
,
2052 if (path
->slots
[0] == i
)
2053 push_space
+= data_size
+ sizeof(*item
);
2055 this_item_size
= btrfs_item_size(right
, item
);
2056 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
2060 push_space
+= this_item_size
+ sizeof(*item
);
2063 if (right
->map_token
) {
2064 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
2065 right
->map_token
= NULL
;
2068 if (push_items
== 0) {
2072 if (!empty
&& push_items
== btrfs_header_nritems(right
))
2075 /* push data from right to left */
2076 copy_extent_buffer(left
, right
,
2077 btrfs_item_nr_offset(btrfs_header_nritems(left
)),
2078 btrfs_item_nr_offset(0),
2079 push_items
* sizeof(struct btrfs_item
));
2081 push_space
= BTRFS_LEAF_DATA_SIZE(root
) -
2082 btrfs_item_offset_nr(right
, push_items
-1);
2084 copy_extent_buffer(left
, right
, btrfs_leaf_data(left
) +
2085 leaf_data_end(root
, left
) - push_space
,
2086 btrfs_leaf_data(right
) +
2087 btrfs_item_offset_nr(right
, push_items
- 1),
2089 old_left_nritems
= btrfs_header_nritems(left
);
2090 BUG_ON(old_left_nritems
< 0);
2092 old_left_item_size
= btrfs_item_offset_nr(left
, old_left_nritems
- 1);
2093 for (i
= old_left_nritems
; i
< old_left_nritems
+ push_items
; i
++) {
2096 item
= btrfs_item_nr(left
, i
);
2097 if (!left
->map_token
) {
2098 map_extent_buffer(left
, (unsigned long)item
,
2099 sizeof(struct btrfs_item
),
2100 &left
->map_token
, &left
->kaddr
,
2101 &left
->map_start
, &left
->map_len
,
2105 ioff
= btrfs_item_offset(left
, item
);
2106 btrfs_set_item_offset(left
, item
,
2107 ioff
- (BTRFS_LEAF_DATA_SIZE(root
) - old_left_item_size
));
2109 btrfs_set_header_nritems(left
, old_left_nritems
+ push_items
);
2110 if (left
->map_token
) {
2111 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
2112 left
->map_token
= NULL
;
2115 /* fixup right node */
2116 if (push_items
> right_nritems
) {
2117 printk("push items %d nr %u\n", push_items
, right_nritems
);
2121 if (push_items
< right_nritems
) {
2122 push_space
= btrfs_item_offset_nr(right
, push_items
- 1) -
2123 leaf_data_end(root
, right
);
2124 memmove_extent_buffer(right
, btrfs_leaf_data(right
) +
2125 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
2126 btrfs_leaf_data(right
) +
2127 leaf_data_end(root
, right
), push_space
);
2129 memmove_extent_buffer(right
, btrfs_item_nr_offset(0),
2130 btrfs_item_nr_offset(push_items
),
2131 (btrfs_header_nritems(right
) - push_items
) *
2132 sizeof(struct btrfs_item
));
2134 right_nritems
-= push_items
;
2135 btrfs_set_header_nritems(right
, right_nritems
);
2136 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
2137 for (i
= 0; i
< right_nritems
; i
++) {
2138 item
= btrfs_item_nr(right
, i
);
2140 if (!right
->map_token
) {
2141 map_extent_buffer(right
, (unsigned long)item
,
2142 sizeof(struct btrfs_item
),
2143 &right
->map_token
, &right
->kaddr
,
2144 &right
->map_start
, &right
->map_len
,
2148 push_space
= push_space
- btrfs_item_size(right
, item
);
2149 btrfs_set_item_offset(right
, item
, push_space
);
2151 if (right
->map_token
) {
2152 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
2153 right
->map_token
= NULL
;
2156 btrfs_mark_buffer_dirty(left
);
2158 btrfs_mark_buffer_dirty(right
);
2160 btrfs_item_key(right
, &disk_key
, 0);
2161 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2165 /* then fixup the leaf pointer in the path */
2166 if (path
->slots
[0] < push_items
) {
2167 path
->slots
[0] += old_left_nritems
;
2168 if (btrfs_header_nritems(path
->nodes
[0]) == 0)
2169 clean_tree_block(trans
, root
, path
->nodes
[0]);
2170 btrfs_tree_unlock(path
->nodes
[0]);
2171 free_extent_buffer(path
->nodes
[0]);
2172 path
->nodes
[0] = left
;
2173 path
->slots
[1] -= 1;
2175 btrfs_tree_unlock(left
);
2176 free_extent_buffer(left
);
2177 path
->slots
[0] -= push_items
;
2179 BUG_ON(path
->slots
[0] < 0);
2182 btrfs_tree_unlock(left
);
2183 free_extent_buffer(left
);
2188 * split the path's leaf in two, making sure there is at least data_size
2189 * available for the resulting leaf level of the path.
2191 * returns 0 if all went well and < 0 on failure.
2193 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
2194 *root
, struct btrfs_key
*ins_key
,
2195 struct btrfs_path
*path
, int data_size
, int extend
)
2198 struct extent_buffer
*l
;
2202 struct extent_buffer
*right
;
2203 int space_needed
= data_size
+ sizeof(struct btrfs_item
);
2210 int num_doubles
= 0;
2211 struct btrfs_disk_key disk_key
;
2214 space_needed
= data_size
;
2217 root_gen
= trans
->transid
;
2221 /* first try to make some room by pushing left and right */
2222 if (ins_key
->type
!= BTRFS_DIR_ITEM_KEY
) {
2223 wret
= push_leaf_right(trans
, root
, path
, data_size
, 0);
2228 wret
= push_leaf_left(trans
, root
, path
, data_size
, 0);
2234 /* did the pushes work? */
2235 if (btrfs_leaf_free_space(root
, l
) >= space_needed
)
2239 if (!path
->nodes
[1]) {
2240 ret
= insert_new_root(trans
, root
, path
, 1);
2247 slot
= path
->slots
[0];
2248 nritems
= btrfs_header_nritems(l
);
2249 mid
= (nritems
+ 1)/ 2;
2251 btrfs_item_key(l
, &disk_key
, 0);
2253 right
= btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
2254 root
->root_key
.objectid
,
2255 root_gen
, disk_key
.objectid
, 0,
2257 if (IS_ERR(right
)) {
2259 return PTR_ERR(right
);
2262 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
2263 btrfs_set_header_bytenr(right
, right
->start
);
2264 btrfs_set_header_generation(right
, trans
->transid
);
2265 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
2266 btrfs_set_header_level(right
, 0);
2267 write_extent_buffer(right
, root
->fs_info
->fsid
,
2268 (unsigned long)btrfs_header_fsid(right
),
2271 write_extent_buffer(right
, root
->fs_info
->chunk_tree_uuid
,
2272 (unsigned long)btrfs_header_chunk_tree_uuid(right
),
2276 leaf_space_used(l
, mid
, nritems
- mid
) + space_needed
>
2277 BTRFS_LEAF_DATA_SIZE(root
)) {
2278 if (slot
>= nritems
) {
2279 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2280 btrfs_set_header_nritems(right
, 0);
2281 wret
= insert_ptr(trans
, root
, path
,
2282 &disk_key
, right
->start
,
2283 path
->slots
[1] + 1, 1);
2287 btrfs_tree_unlock(path
->nodes
[0]);
2288 free_extent_buffer(path
->nodes
[0]);
2289 path
->nodes
[0] = right
;
2291 path
->slots
[1] += 1;
2292 btrfs_mark_buffer_dirty(right
);
2296 if (mid
!= nritems
&&
2297 leaf_space_used(l
, mid
, nritems
- mid
) +
2298 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2303 if (leaf_space_used(l
, 0, mid
+ 1) + space_needed
>
2304 BTRFS_LEAF_DATA_SIZE(root
)) {
2305 if (!extend
&& slot
== 0) {
2306 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2307 btrfs_set_header_nritems(right
, 0);
2308 wret
= insert_ptr(trans
, root
, path
,
2314 btrfs_tree_unlock(path
->nodes
[0]);
2315 free_extent_buffer(path
->nodes
[0]);
2316 path
->nodes
[0] = right
;
2318 if (path
->slots
[1] == 0) {
2319 wret
= fixup_low_keys(trans
, root
,
2320 path
, &disk_key
, 1);
2324 btrfs_mark_buffer_dirty(right
);
2326 } else if (extend
&& slot
== 0) {
2330 if (mid
!= nritems
&&
2331 leaf_space_used(l
, mid
, nritems
- mid
) +
2332 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2338 nritems
= nritems
- mid
;
2339 btrfs_set_header_nritems(right
, nritems
);
2340 data_copy_size
= btrfs_item_end_nr(l
, mid
) - leaf_data_end(root
, l
);
2342 copy_extent_buffer(right
, l
, btrfs_item_nr_offset(0),
2343 btrfs_item_nr_offset(mid
),
2344 nritems
* sizeof(struct btrfs_item
));
2346 copy_extent_buffer(right
, l
,
2347 btrfs_leaf_data(right
) + BTRFS_LEAF_DATA_SIZE(root
) -
2348 data_copy_size
, btrfs_leaf_data(l
) +
2349 leaf_data_end(root
, l
), data_copy_size
);
2351 rt_data_off
= BTRFS_LEAF_DATA_SIZE(root
) -
2352 btrfs_item_end_nr(l
, mid
);
2354 for (i
= 0; i
< nritems
; i
++) {
2355 struct btrfs_item
*item
= btrfs_item_nr(right
, i
);
2358 if (!right
->map_token
) {
2359 map_extent_buffer(right
, (unsigned long)item
,
2360 sizeof(struct btrfs_item
),
2361 &right
->map_token
, &right
->kaddr
,
2362 &right
->map_start
, &right
->map_len
,
2366 ioff
= btrfs_item_offset(right
, item
);
2367 btrfs_set_item_offset(right
, item
, ioff
+ rt_data_off
);
2370 if (right
->map_token
) {
2371 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
2372 right
->map_token
= NULL
;
2375 btrfs_set_header_nritems(l
, mid
);
2377 btrfs_item_key(right
, &disk_key
, 0);
2378 wret
= insert_ptr(trans
, root
, path
, &disk_key
, right
->start
,
2379 path
->slots
[1] + 1, 1);
2383 btrfs_mark_buffer_dirty(right
);
2384 btrfs_mark_buffer_dirty(l
);
2385 BUG_ON(path
->slots
[0] != slot
);
2388 btrfs_tree_unlock(path
->nodes
[0]);
2389 free_extent_buffer(path
->nodes
[0]);
2390 path
->nodes
[0] = right
;
2391 path
->slots
[0] -= mid
;
2392 path
->slots
[1] += 1;
2394 btrfs_tree_unlock(right
);
2395 free_extent_buffer(right
);
2398 BUG_ON(path
->slots
[0] < 0);
2401 BUG_ON(num_doubles
!= 0);
2408 int btrfs_truncate_item(struct btrfs_trans_handle
*trans
,
2409 struct btrfs_root
*root
,
2410 struct btrfs_path
*path
,
2411 u32 new_size
, int from_end
)
2416 struct extent_buffer
*leaf
;
2417 struct btrfs_item
*item
;
2419 unsigned int data_end
;
2420 unsigned int old_data_start
;
2421 unsigned int old_size
;
2422 unsigned int size_diff
;
2425 slot_orig
= path
->slots
[0];
2426 leaf
= path
->nodes
[0];
2427 slot
= path
->slots
[0];
2429 old_size
= btrfs_item_size_nr(leaf
, slot
);
2430 if (old_size
== new_size
)
2433 nritems
= btrfs_header_nritems(leaf
);
2434 data_end
= leaf_data_end(root
, leaf
);
2436 old_data_start
= btrfs_item_offset_nr(leaf
, slot
);
2438 size_diff
= old_size
- new_size
;
2441 BUG_ON(slot
>= nritems
);
2444 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2446 /* first correct the data pointers */
2447 for (i
= slot
; i
< nritems
; i
++) {
2449 item
= btrfs_item_nr(leaf
, i
);
2451 if (!leaf
->map_token
) {
2452 map_extent_buffer(leaf
, (unsigned long)item
,
2453 sizeof(struct btrfs_item
),
2454 &leaf
->map_token
, &leaf
->kaddr
,
2455 &leaf
->map_start
, &leaf
->map_len
,
2459 ioff
= btrfs_item_offset(leaf
, item
);
2460 btrfs_set_item_offset(leaf
, item
, ioff
+ size_diff
);
2463 if (leaf
->map_token
) {
2464 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2465 leaf
->map_token
= NULL
;
2468 /* shift the data */
2470 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2471 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2472 data_end
, old_data_start
+ new_size
- data_end
);
2474 struct btrfs_disk_key disk_key
;
2477 btrfs_item_key(leaf
, &disk_key
, slot
);
2479 if (btrfs_disk_key_type(&disk_key
) == BTRFS_EXTENT_DATA_KEY
) {
2481 struct btrfs_file_extent_item
*fi
;
2483 fi
= btrfs_item_ptr(leaf
, slot
,
2484 struct btrfs_file_extent_item
);
2485 fi
= (struct btrfs_file_extent_item
*)(
2486 (unsigned long)fi
- size_diff
);
2488 if (btrfs_file_extent_type(leaf
, fi
) ==
2489 BTRFS_FILE_EXTENT_INLINE
) {
2490 ptr
= btrfs_item_ptr_offset(leaf
, slot
);
2491 memmove_extent_buffer(leaf
, ptr
,
2493 offsetof(struct btrfs_file_extent_item
,
2498 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2499 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2500 data_end
, old_data_start
- data_end
);
2502 offset
= btrfs_disk_key_offset(&disk_key
);
2503 btrfs_set_disk_key_offset(&disk_key
, offset
+ size_diff
);
2504 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2506 fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2509 item
= btrfs_item_nr(leaf
, slot
);
2510 btrfs_set_item_size(leaf
, item
, new_size
);
2511 btrfs_mark_buffer_dirty(leaf
);
2514 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2515 btrfs_print_leaf(root
, leaf
);
2521 int btrfs_extend_item(struct btrfs_trans_handle
*trans
,
2522 struct btrfs_root
*root
, struct btrfs_path
*path
,
2528 struct extent_buffer
*leaf
;
2529 struct btrfs_item
*item
;
2531 unsigned int data_end
;
2532 unsigned int old_data
;
2533 unsigned int old_size
;
2536 slot_orig
= path
->slots
[0];
2537 leaf
= path
->nodes
[0];
2539 nritems
= btrfs_header_nritems(leaf
);
2540 data_end
= leaf_data_end(root
, leaf
);
2542 if (btrfs_leaf_free_space(root
, leaf
) < data_size
) {
2543 btrfs_print_leaf(root
, leaf
);
2546 slot
= path
->slots
[0];
2547 old_data
= btrfs_item_end_nr(leaf
, slot
);
2550 if (slot
>= nritems
) {
2551 btrfs_print_leaf(root
, leaf
);
2552 printk("slot %d too large, nritems %d\n", slot
, nritems
);
2557 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2559 /* first correct the data pointers */
2560 for (i
= slot
; i
< nritems
; i
++) {
2562 item
= btrfs_item_nr(leaf
, i
);
2564 if (!leaf
->map_token
) {
2565 map_extent_buffer(leaf
, (unsigned long)item
,
2566 sizeof(struct btrfs_item
),
2567 &leaf
->map_token
, &leaf
->kaddr
,
2568 &leaf
->map_start
, &leaf
->map_len
,
2571 ioff
= btrfs_item_offset(leaf
, item
);
2572 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2575 if (leaf
->map_token
) {
2576 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2577 leaf
->map_token
= NULL
;
2580 /* shift the data */
2581 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2582 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2583 data_end
, old_data
- data_end
);
2585 data_end
= old_data
;
2586 old_size
= btrfs_item_size_nr(leaf
, slot
);
2587 item
= btrfs_item_nr(leaf
, slot
);
2588 btrfs_set_item_size(leaf
, item
, old_size
+ data_size
);
2589 btrfs_mark_buffer_dirty(leaf
);
2592 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2593 btrfs_print_leaf(root
, leaf
);
2600 * Given a key and some data, insert an item into the tree.
2601 * This does all the path init required, making room in the tree if needed.
2603 int btrfs_insert_empty_items(struct btrfs_trans_handle
*trans
,
2604 struct btrfs_root
*root
,
2605 struct btrfs_path
*path
,
2606 struct btrfs_key
*cpu_key
, u32
*data_size
,
2609 struct extent_buffer
*leaf
;
2610 struct btrfs_item
*item
;
2618 unsigned int data_end
;
2619 struct btrfs_disk_key disk_key
;
2621 for (i
= 0; i
< nr
; i
++) {
2622 total_data
+= data_size
[i
];
2625 total_size
= total_data
+ (nr
* sizeof(struct btrfs_item
));
2626 ret
= btrfs_search_slot(trans
, root
, cpu_key
, path
, total_size
, 1);
2633 slot_orig
= path
->slots
[0];
2634 leaf
= path
->nodes
[0];
2636 nritems
= btrfs_header_nritems(leaf
);
2637 data_end
= leaf_data_end(root
, leaf
);
2639 if (btrfs_leaf_free_space(root
, leaf
) <
2640 sizeof(struct btrfs_item
) + total_size
) {
2641 btrfs_print_leaf(root
, leaf
);
2642 printk("not enough freespace need %u have %d\n",
2643 total_size
, btrfs_leaf_free_space(root
, leaf
));
2647 slot
= path
->slots
[0];
2650 if (slot
!= nritems
) {
2652 unsigned int old_data
= btrfs_item_end_nr(leaf
, slot
);
2654 if (old_data
< data_end
) {
2655 btrfs_print_leaf(root
, leaf
);
2656 printk("slot %d old_data %d data_end %d\n",
2657 slot
, old_data
, data_end
);
2661 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2663 /* first correct the data pointers */
2664 WARN_ON(leaf
->map_token
);
2665 for (i
= slot
; i
< nritems
; i
++) {
2668 item
= btrfs_item_nr(leaf
, i
);
2669 if (!leaf
->map_token
) {
2670 map_extent_buffer(leaf
, (unsigned long)item
,
2671 sizeof(struct btrfs_item
),
2672 &leaf
->map_token
, &leaf
->kaddr
,
2673 &leaf
->map_start
, &leaf
->map_len
,
2677 ioff
= btrfs_item_offset(leaf
, item
);
2678 btrfs_set_item_offset(leaf
, item
, ioff
- total_data
);
2680 if (leaf
->map_token
) {
2681 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2682 leaf
->map_token
= NULL
;
2685 /* shift the items */
2686 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ nr
),
2687 btrfs_item_nr_offset(slot
),
2688 (nritems
- slot
) * sizeof(struct btrfs_item
));
2690 /* shift the data */
2691 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2692 data_end
- total_data
, btrfs_leaf_data(leaf
) +
2693 data_end
, old_data
- data_end
);
2694 data_end
= old_data
;
2697 /* setup the item for the new data */
2698 for (i
= 0; i
< nr
; i
++) {
2699 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
+ i
);
2700 btrfs_set_item_key(leaf
, &disk_key
, slot
+ i
);
2701 item
= btrfs_item_nr(leaf
, slot
+ i
);
2702 btrfs_set_item_offset(leaf
, item
, data_end
- data_size
[i
]);
2703 data_end
-= data_size
[i
];
2704 btrfs_set_item_size(leaf
, item
, data_size
[i
]);
2706 btrfs_set_header_nritems(leaf
, nritems
+ nr
);
2707 btrfs_mark_buffer_dirty(leaf
);
2711 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
);
2712 ret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2715 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2716 btrfs_print_leaf(root
, leaf
);
2724 * Given a key and some data, insert an item into the tree.
2725 * This does all the path init required, making room in the tree if needed.
2727 int btrfs_insert_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
2728 *root
, struct btrfs_key
*cpu_key
, void *data
, u32
2732 struct btrfs_path
*path
;
2733 struct extent_buffer
*leaf
;
2736 path
= btrfs_alloc_path();
2738 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
2740 leaf
= path
->nodes
[0];
2741 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2742 write_extent_buffer(leaf
, data
, ptr
, data_size
);
2743 btrfs_mark_buffer_dirty(leaf
);
2745 btrfs_free_path(path
);
2750 * delete the pointer from a given node.
2752 * If the delete empties a node, the node is removed from the tree,
2753 * continuing all the way the root if required. The root is converted into
2754 * a leaf if all the nodes are emptied.
2756 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2757 struct btrfs_path
*path
, int level
, int slot
)
2759 struct extent_buffer
*parent
= path
->nodes
[level
];
2764 nritems
= btrfs_header_nritems(parent
);
2765 if (slot
!= nritems
-1) {
2766 memmove_extent_buffer(parent
,
2767 btrfs_node_key_ptr_offset(slot
),
2768 btrfs_node_key_ptr_offset(slot
+ 1),
2769 sizeof(struct btrfs_key_ptr
) *
2770 (nritems
- slot
- 1));
2773 btrfs_set_header_nritems(parent
, nritems
);
2774 if (nritems
== 0 && parent
== root
->node
) {
2775 BUG_ON(btrfs_header_level(root
->node
) != 1);
2776 /* just turn the root into a leaf and break */
2777 btrfs_set_header_level(root
->node
, 0);
2778 } else if (slot
== 0) {
2779 struct btrfs_disk_key disk_key
;
2781 btrfs_node_key(parent
, &disk_key
, 0);
2782 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, level
+ 1);
2786 btrfs_mark_buffer_dirty(parent
);
2791 * delete the item at the leaf level in path. If that empties
2792 * the leaf, remove it from the tree
2794 int btrfs_del_items(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2795 struct btrfs_path
*path
, int slot
, int nr
)
2797 struct extent_buffer
*leaf
;
2798 struct btrfs_item
*item
;
2806 leaf
= path
->nodes
[0];
2807 last_off
= btrfs_item_offset_nr(leaf
, slot
+ nr
- 1);
2809 for (i
= 0; i
< nr
; i
++)
2810 dsize
+= btrfs_item_size_nr(leaf
, slot
+ i
);
2812 nritems
= btrfs_header_nritems(leaf
);
2814 if (slot
+ nr
!= nritems
) {
2816 int data_end
= leaf_data_end(root
, leaf
);
2818 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2820 btrfs_leaf_data(leaf
) + data_end
,
2821 last_off
- data_end
);
2823 for (i
= slot
+ nr
; i
< nritems
; i
++) {
2826 item
= btrfs_item_nr(leaf
, i
);
2827 if (!leaf
->map_token
) {
2828 map_extent_buffer(leaf
, (unsigned long)item
,
2829 sizeof(struct btrfs_item
),
2830 &leaf
->map_token
, &leaf
->kaddr
,
2831 &leaf
->map_start
, &leaf
->map_len
,
2834 ioff
= btrfs_item_offset(leaf
, item
);
2835 btrfs_set_item_offset(leaf
, item
, ioff
+ dsize
);
2838 if (leaf
->map_token
) {
2839 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2840 leaf
->map_token
= NULL
;
2843 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
),
2844 btrfs_item_nr_offset(slot
+ nr
),
2845 sizeof(struct btrfs_item
) *
2846 (nritems
- slot
- nr
));
2848 btrfs_set_header_nritems(leaf
, nritems
- nr
);
2851 /* delete the leaf if we've emptied it */
2853 if (leaf
== root
->node
) {
2854 btrfs_set_header_level(leaf
, 0);
2856 u64 root_gen
= btrfs_header_generation(path
->nodes
[1]);
2857 wret
= del_ptr(trans
, root
, path
, 1, path
->slots
[1]);
2860 wret
= btrfs_free_extent(trans
, root
,
2861 leaf
->start
, leaf
->len
,
2862 btrfs_header_owner(path
->nodes
[1]),
2868 int used
= leaf_space_used(leaf
, 0, nritems
);
2870 struct btrfs_disk_key disk_key
;
2872 btrfs_item_key(leaf
, &disk_key
, 0);
2873 wret
= fixup_low_keys(trans
, root
, path
,
2879 /* delete the leaf if it is mostly empty */
2880 if (used
< BTRFS_LEAF_DATA_SIZE(root
) / 4) {
2881 /* push_leaf_left fixes the path.
2882 * make sure the path still points to our leaf
2883 * for possible call to del_ptr below
2885 slot
= path
->slots
[1];
2886 extent_buffer_get(leaf
);
2888 wret
= push_leaf_left(trans
, root
, path
, 1, 1);
2889 if (wret
< 0 && wret
!= -ENOSPC
)
2892 if (path
->nodes
[0] == leaf
&&
2893 btrfs_header_nritems(leaf
)) {
2894 wret
= push_leaf_right(trans
, root
, path
, 1, 1);
2895 if (wret
< 0 && wret
!= -ENOSPC
)
2899 if (btrfs_header_nritems(leaf
) == 0) {
2901 u64 bytenr
= leaf
->start
;
2902 u32 blocksize
= leaf
->len
;
2904 root_gen
= btrfs_header_generation(
2907 wret
= del_ptr(trans
, root
, path
, 1, slot
);
2911 free_extent_buffer(leaf
);
2912 wret
= btrfs_free_extent(trans
, root
, bytenr
,
2914 btrfs_header_owner(path
->nodes
[1]),
2919 /* if we're still in the path, make sure
2920 * we're dirty. Otherwise, one of the
2921 * push_leaf functions must have already
2922 * dirtied this buffer
2924 if (path
->nodes
[0] == leaf
)
2925 btrfs_mark_buffer_dirty(leaf
);
2926 free_extent_buffer(leaf
);
2929 btrfs_mark_buffer_dirty(leaf
);
2936 * search the tree again to find a leaf with lesser keys
2937 * returns 0 if it found something or 1 if there are no lesser leaves.
2938 * returns < 0 on io errors.
2940 int btrfs_prev_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2942 struct btrfs_key key
;
2943 struct btrfs_disk_key found_key
;
2946 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, 0);
2950 else if (key
.type
> 0)
2952 else if (key
.objectid
> 0)
2957 btrfs_release_path(root
, path
);
2958 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
2961 btrfs_item_key(path
->nodes
[0], &found_key
, 0);
2962 ret
= comp_keys(&found_key
, &key
);
2969 * A helper function to walk down the tree starting at min_key, and looking
2970 * for nodes or leaves that are either in cache or have a minimum
2971 * transaction id. This is used by the btree defrag code, but could
2972 * also be used to search for blocks that have changed since a given
2975 * This does not cow, but it does stuff the starting key it finds back
2976 * into min_key, so you can call btrfs_search_slot with cow=1 on the
2977 * key and get a writable path.
2979 * This does lock as it descends, and path->keep_locks should be set
2980 * to 1 by the caller.
2982 * This honors path->lowest_level to prevent descent past a given level
2985 * returns zero if something useful was found, < 0 on error and 1 if there
2986 * was nothing in the tree that matched the search criteria.
2988 int btrfs_search_forward(struct btrfs_root
*root
, struct btrfs_key
*min_key
,
2989 struct btrfs_path
*path
, int cache_only
,
2992 struct extent_buffer
*cur
;
2993 struct btrfs_key found_key
;
3001 cur
= btrfs_lock_root_node(root
);
3002 level
= btrfs_header_level(cur
);
3003 path
->nodes
[level
] = cur
;
3004 path
->locks
[level
] = 1;
3006 if (btrfs_header_generation(cur
) < min_trans
) {
3011 nritems
= btrfs_header_nritems(cur
);
3012 level
= btrfs_header_level(cur
);
3013 sret
= bin_search(cur
, min_key
, level
, &slot
);
3015 /* at level = 0, we're done, setup the path and exit */
3018 path
->slots
[level
] = slot
;
3019 btrfs_item_key_to_cpu(cur
, &found_key
, slot
);
3022 if (sret
&& slot
> 0)
3025 * check this node pointer against the cache_only and
3026 * min_trans parameters. If it isn't in cache or is too
3027 * old, skip to the next one.
3029 while(slot
< nritems
) {
3032 struct extent_buffer
*tmp
;
3033 blockptr
= btrfs_node_blockptr(cur
, slot
);
3034 gen
= btrfs_node_ptr_generation(cur
, slot
);
3035 if (gen
< min_trans
) {
3042 tmp
= btrfs_find_tree_block(root
, blockptr
,
3043 btrfs_level_size(root
, level
- 1));
3045 if (tmp
&& btrfs_buffer_uptodate(tmp
, gen
)) {
3046 free_extent_buffer(tmp
);
3050 free_extent_buffer(tmp
);
3054 * we didn't find a candidate key in this node, walk forward
3055 * and find another one
3057 if (slot
>= nritems
) {
3058 ret
= btrfs_find_next_key(root
, path
, min_key
, level
,
3059 cache_only
, min_trans
);
3061 btrfs_release_path(root
, path
);
3067 /* save our key for returning back */
3068 btrfs_node_key_to_cpu(cur
, &found_key
, slot
);
3069 path
->slots
[level
] = slot
;
3070 if (level
== path
->lowest_level
) {
3072 unlock_up(path
, level
, 1);
3075 cur
= read_node_slot(root
, cur
, slot
);
3077 btrfs_tree_lock(cur
);
3078 path
->locks
[level
- 1] = 1;
3079 path
->nodes
[level
- 1] = cur
;
3080 unlock_up(path
, level
, 1);
3084 memcpy(min_key
, &found_key
, sizeof(found_key
));
3089 * this is similar to btrfs_next_leaf, but does not try to preserve
3090 * and fixup the path. It looks for and returns the next key in the
3091 * tree based on the current path and the cache_only and min_trans
3094 * 0 is returned if another key is found, < 0 if there are any errors
3095 * and 1 is returned if there are no higher keys in the tree
3097 * path->keep_locks should be set to 1 on the search made before
3098 * calling this function.
3100 int btrfs_find_next_key(struct btrfs_root
*root
, struct btrfs_path
*path
,
3101 struct btrfs_key
*key
, int lowest_level
,
3102 int cache_only
, u64 min_trans
)
3104 int level
= lowest_level
;
3106 struct extent_buffer
*c
;
3108 while(level
< BTRFS_MAX_LEVEL
) {
3109 if (!path
->nodes
[level
])
3112 slot
= path
->slots
[level
] + 1;
3113 c
= path
->nodes
[level
];
3115 if (slot
>= btrfs_header_nritems(c
)) {
3117 if (level
== BTRFS_MAX_LEVEL
) {
3123 btrfs_item_key_to_cpu(c
, key
, slot
);
3125 u64 blockptr
= btrfs_node_blockptr(c
, slot
);
3126 u64 gen
= btrfs_node_ptr_generation(c
, slot
);
3129 struct extent_buffer
*cur
;
3130 cur
= btrfs_find_tree_block(root
, blockptr
,
3131 btrfs_level_size(root
, level
- 1));
3132 if (!cur
|| !btrfs_buffer_uptodate(cur
, gen
)) {
3135 free_extent_buffer(cur
);
3138 free_extent_buffer(cur
);
3140 if (gen
< min_trans
) {
3144 btrfs_node_key_to_cpu(c
, key
, slot
);
3152 * search the tree again to find a leaf with greater keys
3153 * returns 0 if it found something or 1 if there are no greater leaves.
3154 * returns < 0 on io errors.
3156 int btrfs_next_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
3160 struct extent_buffer
*c
;
3161 struct extent_buffer
*next
= NULL
;
3162 struct btrfs_key key
;
3166 nritems
= btrfs_header_nritems(path
->nodes
[0]);
3171 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, nritems
- 1);
3173 btrfs_release_path(root
, path
);
3174 path
->keep_locks
= 1;
3175 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
3176 path
->keep_locks
= 0;
3181 nritems
= btrfs_header_nritems(path
->nodes
[0]);
3183 * by releasing the path above we dropped all our locks. A balance
3184 * could have added more items next to the key that used to be
3185 * at the very end of the block. So, check again here and
3186 * advance the path if there are now more items available.
3188 if (nritems
> 0 && path
->slots
[0] < nritems
- 1) {
3193 while(level
< BTRFS_MAX_LEVEL
) {
3194 if (!path
->nodes
[level
])
3197 slot
= path
->slots
[level
] + 1;
3198 c
= path
->nodes
[level
];
3199 if (slot
>= btrfs_header_nritems(c
)) {
3201 if (level
== BTRFS_MAX_LEVEL
) {
3208 btrfs_tree_unlock(next
);
3209 free_extent_buffer(next
);
3212 if (level
== 1 && (path
->locks
[1] || path
->skip_locking
) &&
3214 reada_for_search(root
, path
, level
, slot
, 0);
3216 next
= read_node_slot(root
, c
, slot
);
3217 if (!path
->skip_locking
) {
3218 WARN_ON(!btrfs_tree_locked(c
));
3219 btrfs_tree_lock(next
);
3223 path
->slots
[level
] = slot
;
3226 c
= path
->nodes
[level
];
3227 if (path
->locks
[level
])
3228 btrfs_tree_unlock(c
);
3229 free_extent_buffer(c
);
3230 path
->nodes
[level
] = next
;
3231 path
->slots
[level
] = 0;
3232 if (!path
->skip_locking
)
3233 path
->locks
[level
] = 1;
3236 if (level
== 1 && path
->locks
[1] && path
->reada
)
3237 reada_for_search(root
, path
, level
, slot
, 0);
3238 next
= read_node_slot(root
, next
, 0);
3239 if (!path
->skip_locking
) {
3240 WARN_ON(!btrfs_tree_locked(path
->nodes
[level
]));
3241 btrfs_tree_lock(next
);
3245 unlock_up(path
, 0, 1);
3250 * this uses btrfs_prev_leaf to walk backwards in the tree, and keeps
3251 * searching until it gets past min_objectid or finds an item of 'type'
3253 * returns 0 if something is found, 1 if nothing was found and < 0 on error
3255 int btrfs_previous_item(struct btrfs_root
*root
,
3256 struct btrfs_path
*path
, u64 min_objectid
,
3259 struct btrfs_key found_key
;
3260 struct extent_buffer
*leaf
;
3264 if (path
->slots
[0] == 0) {
3265 ret
= btrfs_prev_leaf(root
, path
);
3271 leaf
= path
->nodes
[0];
3272 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
3273 if (found_key
.type
== type
)