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/highmem.h>
22 #include "transaction.h"
23 #include "print-tree.h"
25 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
26 *root
, struct btrfs_path
*path
, int level
);
27 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
28 *root
, struct btrfs_key
*ins_key
,
29 struct btrfs_path
*path
, int data_size
);
30 static int push_node_left(struct btrfs_trans_handle
*trans
,
31 struct btrfs_root
*root
, struct extent_buffer
*dst
,
32 struct extent_buffer
*src
);
33 static int balance_node_right(struct btrfs_trans_handle
*trans
,
34 struct btrfs_root
*root
,
35 struct extent_buffer
*dst_buf
,
36 struct extent_buffer
*src_buf
);
37 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
38 struct btrfs_path
*path
, int level
, int slot
);
40 inline void btrfs_init_path(struct btrfs_path
*p
)
42 memset(p
, 0, sizeof(*p
));
45 struct btrfs_path
*btrfs_alloc_path(void)
47 struct btrfs_path
*path
;
48 path
= kmem_cache_alloc(btrfs_path_cachep
, GFP_NOFS
);
50 btrfs_init_path(path
);
56 void btrfs_free_path(struct btrfs_path
*p
)
58 btrfs_release_path(NULL
, p
);
59 kmem_cache_free(btrfs_path_cachep
, p
);
62 void btrfs_release_path(struct btrfs_root
*root
, struct btrfs_path
*p
)
65 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++) {
68 free_extent_buffer(p
->nodes
[i
]);
70 memset(p
, 0, sizeof(*p
));
73 static int __btrfs_cow_block(struct btrfs_trans_handle
*trans
,
74 struct btrfs_root
*root
,
75 struct extent_buffer
*buf
,
76 struct extent_buffer
*parent
, int parent_slot
,
77 struct extent_buffer
**cow_ret
,
78 u64 search_start
, u64 empty_size
)
80 struct extent_buffer
*cow
;
82 int different_trans
= 0;
84 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
86 cow
= btrfs_alloc_free_block(trans
, root
, buf
->len
,
87 search_start
, empty_size
);
91 cow
->alloc_addr
= (unsigned long)__builtin_return_address(0);
93 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
94 btrfs_set_header_bytenr(cow
, cow
->start
);
95 btrfs_set_header_generation(cow
, trans
->transid
);
96 btrfs_set_header_owner(cow
, root
->root_key
.objectid
);
98 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
99 if (btrfs_header_generation(buf
) != trans
->transid
) {
101 ret
= btrfs_inc_ref(trans
, root
, buf
);
105 clean_tree_block(trans
, root
, buf
);
108 if (buf
== root
->node
) {
110 extent_buffer_get(cow
);
111 if (buf
!= root
->commit_root
) {
112 btrfs_free_extent(trans
, root
, buf
->start
,
115 free_extent_buffer(buf
);
117 btrfs_set_node_blockptr(parent
, parent_slot
,
119 btrfs_mark_buffer_dirty(parent
);
120 WARN_ON(btrfs_header_generation(parent
) != trans
->transid
);
121 btrfs_free_extent(trans
, root
, buf
->start
, buf
->len
, 1);
123 free_extent_buffer(buf
);
124 btrfs_mark_buffer_dirty(cow
);
129 int btrfs_cow_block(struct btrfs_trans_handle
*trans
,
130 struct btrfs_root
*root
, struct extent_buffer
*buf
,
131 struct extent_buffer
*parent
, int parent_slot
,
132 struct extent_buffer
**cow_ret
)
136 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
137 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
138 root
->fs_info
->running_transaction
->transid
);
141 if (trans
->transid
!= root
->fs_info
->generation
) {
142 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
143 root
->fs_info
->generation
);
146 if (btrfs_header_generation(buf
) == trans
->transid
) {
151 search_start
= buf
->start
& ~((u64
)BTRFS_BLOCK_GROUP_SIZE
- 1);
152 ret
= __btrfs_cow_block(trans
, root
, buf
, parent
,
153 parent_slot
, cow_ret
, search_start
, 0);
154 (*cow_ret
)->alloc_addr
= (unsigned long)__builtin_return_address(0);
159 static int close_blocks(u64 blocknr
, u64 other
)
161 if (blocknr
< other
&& other
- blocknr
< 8)
163 if (blocknr
> other
&& blocknr
- other
< 8)
168 static int should_defrag_leaf(struct extent_buffer
*eb
)
171 struct btrfs_leaf
*leaf
= btrfs_buffer_leaf(eb
);
172 struct btrfs_disk_key
*key
;
175 if (buffer_defrag(bh
))
178 nritems
= btrfs_header_nritems(&leaf
->header
);
182 key
= &leaf
->items
[0].key
;
183 if (btrfs_disk_key_type(key
) == BTRFS_DIR_ITEM_KEY
)
186 key
= &leaf
->items
[nritems
-1].key
;
187 if (btrfs_disk_key_type(key
) == BTRFS_DIR_ITEM_KEY
)
190 key
= &leaf
->items
[nritems
/2].key
;
191 if (btrfs_disk_key_type(key
) == BTRFS_DIR_ITEM_KEY
)
198 int btrfs_realloc_node(struct btrfs_trans_handle
*trans
,
199 struct btrfs_root
*root
, struct extent_buffer
*parent
,
200 int cache_only
, u64
*last_ret
)
204 struct btrfs_node
*parent_node
;
205 struct extent_buffer
*cur_eb
;
206 struct extent_buffer
*tmp_eb
;
208 u64 search_start
= *last_ret
;
218 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
219 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
220 root
->fs_info
->running_transaction
->transid
);
223 if (trans
->transid
!= root
->fs_info
->generation
) {
224 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
225 root
->fs_info
->generation
);
228 if (buffer_defrag_done(parent
))
231 parent_node
= btrfs_buffer_node(parent
);
232 parent_nritems
= btrfs_header_nritems(&parent_node
->header
);
233 parent_level
= btrfs_header_level(&parent_node
->header
);
236 end_slot
= parent_nritems
;
238 if (parent_nritems
== 1)
241 for (i
= start_slot
; i
< end_slot
; i
++) {
243 blocknr
= btrfs_node_blockptr(parent_node
, i
);
245 last_block
= blocknr
;
247 other
= btrfs_node_blockptr(parent_node
, i
- 1);
248 close
= close_blocks(blocknr
, other
);
250 if (close
&& i
< end_slot
- 1) {
251 other
= btrfs_node_blockptr(parent_node
, i
+ 1);
252 close
= close_blocks(blocknr
, other
);
255 last_block
= blocknr
;
259 cur_bh
= btrfs_find_tree_block(root
, blocknr
);
260 if (!cur_bh
|| !buffer_uptodate(cur_bh
) ||
261 buffer_locked(cur_bh
) ||
262 (parent_level
!= 1 && !buffer_defrag(cur_bh
)) ||
263 (parent_level
== 1 && !should_defrag_leaf(cur_bh
))) {
268 if (!cur_bh
|| !buffer_uptodate(cur_bh
) ||
269 buffer_locked(cur_bh
)) {
271 cur_bh
= read_tree_block(root
, blocknr
);
274 if (search_start
== 0)
275 search_start
= last_block
& ~((u64
)65535);
277 err
= __btrfs_cow_block(trans
, root
, cur_bh
, parent
, i
,
278 &tmp_bh
, search_start
,
279 min(8, end_slot
- i
));
284 search_start
= bh_blocknr(tmp_bh
);
285 *last_ret
= search_start
;
286 if (parent_level
== 1)
287 clear_buffer_defrag(tmp_bh
);
288 set_buffer_defrag_done(tmp_bh
);
296 * The leaf data grows from end-to-front in the node.
297 * this returns the address of the start of the last item,
298 * which is the stop of the leaf data stack
300 static inline unsigned int leaf_data_end(struct btrfs_root
*root
,
301 struct extent_buffer
*leaf
)
303 u32 nr
= btrfs_header_nritems(leaf
);
305 return BTRFS_LEAF_DATA_SIZE(root
);
306 return btrfs_item_offset_nr(leaf
, nr
- 1);
310 * compare two keys in a memcmp fashion
312 static int comp_keys(struct btrfs_disk_key
*disk
, struct btrfs_key
*k2
)
316 btrfs_disk_key_to_cpu(&k1
, disk
);
318 if (k1
.objectid
> k2
->objectid
)
320 if (k1
.objectid
< k2
->objectid
)
322 if (k1
.type
> k2
->type
)
324 if (k1
.type
< k2
->type
)
326 if (k1
.offset
> k2
->offset
)
328 if (k1
.offset
< k2
->offset
)
333 static int check_node(struct btrfs_root
*root
, struct btrfs_path
*path
,
336 struct extent_buffer
*parent
= NULL
;
337 struct extent_buffer
*node
= path
->nodes
[level
];
338 struct btrfs_disk_key parent_key
;
339 struct btrfs_disk_key node_key
;
342 struct btrfs_key cpukey
;
343 u32 nritems
= btrfs_header_nritems(node
);
345 if (path
->nodes
[level
+ 1])
346 parent
= path
->nodes
[level
+ 1];
348 slot
= path
->slots
[level
];
349 BUG_ON(nritems
== 0);
351 parent_slot
= path
->slots
[level
+ 1];
352 btrfs_node_key(parent
, &parent_key
, parent_slot
);
353 btrfs_node_key(node
, &node_key
, 0);
354 BUG_ON(memcmp(&parent_key
, &node_key
,
355 sizeof(struct btrfs_disk_key
)));
356 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
357 btrfs_header_bytenr(node
));
359 BUG_ON(nritems
> BTRFS_NODEPTRS_PER_BLOCK(root
));
361 btrfs_node_key_to_cpu(node
, &cpukey
, slot
- 1);
362 btrfs_node_key(node
, &node_key
, slot
);
363 BUG_ON(comp_keys(&node_key
, &cpukey
) <= 0);
365 if (slot
< nritems
- 1) {
366 btrfs_node_key_to_cpu(node
, &cpukey
, slot
+ 1);
367 btrfs_node_key(node
, &node_key
, slot
);
368 BUG_ON(comp_keys(&node_key
, &cpukey
) >= 0);
373 static int check_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
,
376 struct extent_buffer
*leaf
= path
->nodes
[level
];
377 struct extent_buffer
*parent
= NULL
;
379 struct btrfs_key cpukey
;
380 struct btrfs_disk_key parent_key
;
381 struct btrfs_disk_key leaf_key
;
382 int slot
= path
->slots
[0];
384 u32 nritems
= btrfs_header_nritems(leaf
);
386 if (path
->nodes
[level
+ 1])
387 parent
= path
->nodes
[level
+ 1];
393 parent_slot
= path
->slots
[level
+ 1];
394 btrfs_node_key(parent
, &parent_key
, parent_slot
);
395 btrfs_item_key(leaf
, &leaf_key
, 0);
397 BUG_ON(memcmp(&parent_key
, &leaf_key
,
398 sizeof(struct btrfs_disk_key
)));
399 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
400 btrfs_header_bytenr(leaf
));
403 for (i
= 0; nritems
> 1 && i
< nritems
- 2; i
++) {
404 btrfs_item_key_to_cpu(leaf
, &cpukey
, i
+ 1);
405 btrfs_item_key(leaf
, &leaf_key
, i
);
406 if (comp_keys(&leaf_key
, &cpukey
) >= 0) {
407 btrfs_print_leaf(root
, leaf
);
408 printk("slot %d offset bad key\n", i
);
411 if (btrfs_item_offset_nr(leaf
, i
) !=
412 btrfs_item_end_nr(leaf
, i
+ 1)) {
413 btrfs_print_leaf(root
, leaf
);
414 printk("slot %d offset bad\n", i
);
418 if (btrfs_item_offset_nr(leaf
, i
) +
419 btrfs_item_size_nr(leaf
, i
) !=
420 BTRFS_LEAF_DATA_SIZE(root
)) {
421 btrfs_print_leaf(root
, leaf
);
422 printk("slot %d first offset bad\n", i
);
428 if (btrfs_item_size_nr(leaf
, nritems
- 1) > 4096) {
429 btrfs_print_leaf(root
, leaf
);
430 printk("slot %d bad size \n", nritems
- 1);
435 if (slot
!= 0 && slot
< nritems
- 1) {
436 btrfs_item_key(leaf
, &leaf_key
, slot
);
437 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
- 1);
438 if (comp_keys(&leaf_key
, &cpukey
) <= 0) {
439 btrfs_print_leaf(root
, leaf
);
440 printk("slot %d offset bad key\n", slot
);
443 if (btrfs_item_offset_nr(leaf
, slot
- 1) !=
444 btrfs_item_end_nr(leaf
, slot
)) {
445 btrfs_print_leaf(root
, leaf
);
446 printk("slot %d offset bad\n", slot
);
450 if (slot
< nritems
- 1) {
451 btrfs_item_key(leaf
, &leaf_key
, slot
);
452 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
+ 1);
453 BUG_ON(comp_keys(&leaf_key
, &cpukey
) >= 0);
454 if (btrfs_item_offset_nr(leaf
, slot
) !=
455 btrfs_item_end_nr(leaf
, slot
+ 1)) {
456 btrfs_print_leaf(root
, leaf
);
457 printk("slot %d offset bad\n", slot
);
461 BUG_ON(btrfs_item_offset_nr(leaf
, 0) +
462 btrfs_item_size_nr(leaf
, 0) != BTRFS_LEAF_DATA_SIZE(root
));
466 static int check_block(struct btrfs_root
*root
, struct btrfs_path
*path
,
470 struct extent_buffer
*buf
= path
->nodes
[level
];
472 if (memcmp_extent_buffer(buf
, root
->fs_info
->fsid
,
473 (unsigned long)btrfs_header_fsid(buf
),
475 printk("warning bad block %Lu\n", buf
->start
);
480 return check_leaf(root
, path
, level
);
481 return check_node(root
, path
, level
);
485 * search for key in the extent_buffer. The items start at offset p,
486 * and they are item_size apart. There are 'max' items in p.
488 * the slot in the array is returned via slot, and it points to
489 * the place where you would insert key if it is not found in
492 * slot may point to max if the key is bigger than all of the keys
494 static int generic_bin_search(struct extent_buffer
*eb
, unsigned long p
,
495 int item_size
, struct btrfs_key
*key
,
502 struct btrfs_disk_key
*tmp
= NULL
;
503 struct btrfs_disk_key unaligned
;
504 unsigned long offset
;
505 char *map_token
= NULL
;
507 unsigned long map_start
= 0;
508 unsigned long map_len
= 0;
512 mid
= (low
+ high
) / 2;
513 offset
= p
+ mid
* item_size
;
515 if (!map_token
|| offset
< map_start
||
516 (offset
+ sizeof(struct btrfs_disk_key
)) >
517 map_start
+ map_len
) {
519 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
522 err
= map_extent_buffer(eb
, offset
,
523 sizeof(struct btrfs_disk_key
),
525 &map_start
, &map_len
, KM_USER0
);
528 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
531 read_extent_buffer(eb
, &unaligned
,
532 offset
, sizeof(unaligned
));
537 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
540 ret
= comp_keys(tmp
, key
);
549 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
555 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
560 * simple bin_search frontend that does the right thing for
563 static int bin_search(struct extent_buffer
*eb
, struct btrfs_key
*key
,
564 int level
, int *slot
)
567 return generic_bin_search(eb
,
568 offsetof(struct btrfs_leaf
, items
),
569 sizeof(struct btrfs_item
),
570 key
, btrfs_header_nritems(eb
),
573 return generic_bin_search(eb
,
574 offsetof(struct btrfs_node
, ptrs
),
575 sizeof(struct btrfs_key_ptr
),
576 key
, btrfs_header_nritems(eb
),
582 static struct extent_buffer
*read_node_slot(struct btrfs_root
*root
,
583 struct extent_buffer
*parent
, int slot
)
587 if (slot
>= btrfs_header_nritems(parent
))
589 return read_tree_block(root
, btrfs_node_blockptr(parent
, slot
),
590 btrfs_level_size(root
, btrfs_header_level(parent
) - 1));
593 static int balance_level(struct btrfs_trans_handle
*trans
, struct btrfs_root
594 *root
, struct btrfs_path
*path
, int level
)
596 struct extent_buffer
*right
= NULL
;
597 struct extent_buffer
*mid
;
598 struct extent_buffer
*left
= NULL
;
599 struct extent_buffer
*parent
= NULL
;
603 int orig_slot
= path
->slots
[level
];
604 int err_on_enospc
= 0;
610 mid
= path
->nodes
[level
];
611 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
613 if (level
< BTRFS_MAX_LEVEL
- 1)
614 parent
= path
->nodes
[level
+ 1];
615 pslot
= path
->slots
[level
+ 1];
618 * deal with the case where there is only one pointer in the root
619 * by promoting the node below to a root
622 struct extent_buffer
*child
;
624 if (btrfs_header_nritems(mid
) != 1)
627 /* promote the child to a root */
628 child
= read_node_slot(root
, mid
, 0);
631 path
->nodes
[level
] = NULL
;
632 clean_tree_block(trans
, root
, mid
);
633 wait_on_tree_block_writeback(root
, mid
);
634 /* once for the path */
635 free_extent_buffer(mid
);
636 ret
= btrfs_free_extent(trans
, root
, mid
->start
, mid
->len
, 1);
637 /* once for the root ptr */
638 free_extent_buffer(mid
);
641 if (btrfs_header_nritems(mid
) >
642 BTRFS_NODEPTRS_PER_BLOCK(root
) / 4)
645 if (btrfs_header_nritems(mid
) < 2)
648 left
= read_node_slot(root
, parent
, pslot
- 1);
650 wret
= btrfs_cow_block(trans
, root
, left
,
651 parent
, pslot
- 1, &left
);
657 right
= read_node_slot(root
, parent
, pslot
+ 1);
659 wret
= btrfs_cow_block(trans
, root
, right
,
660 parent
, pslot
+ 1, &right
);
667 /* first, try to make some room in the middle buffer */
669 orig_slot
+= btrfs_header_nritems(left
);
670 wret
= push_node_left(trans
, root
, left
, mid
);
673 if (btrfs_header_nritems(mid
) < 2)
678 * then try to empty the right most buffer into the middle
681 wret
= push_node_left(trans
, root
, mid
, right
);
682 if (wret
< 0 && wret
!= -ENOSPC
)
684 if (btrfs_header_nritems(right
) == 0) {
685 u64 bytenr
= right
->start
;
686 u32 blocksize
= right
->len
;
688 clean_tree_block(trans
, root
, right
);
689 wait_on_tree_block_writeback(root
, right
);
690 free_extent_buffer(right
);
692 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
+
696 wret
= btrfs_free_extent(trans
, root
, bytenr
,
701 struct btrfs_disk_key right_key
;
702 btrfs_node_key(right
, &right_key
, 0);
703 btrfs_set_node_key(parent
, &right_key
, pslot
+ 1);
704 btrfs_mark_buffer_dirty(parent
);
707 if (btrfs_header_nritems(mid
) == 1) {
709 * we're not allowed to leave a node with one item in the
710 * tree during a delete. A deletion from lower in the tree
711 * could try to delete the only pointer in this node.
712 * So, pull some keys from the left.
713 * There has to be a left pointer at this point because
714 * otherwise we would have pulled some pointers from the
718 wret
= balance_node_right(trans
, root
, mid
, left
);
725 if (btrfs_header_nritems(mid
) == 0) {
726 /* we've managed to empty the middle node, drop it */
727 u64 bytenr
= mid
->start
;
728 u32 blocksize
= mid
->len
;
729 clean_tree_block(trans
, root
, mid
);
730 wait_on_tree_block_writeback(root
, mid
);
731 free_extent_buffer(mid
);
733 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
);
736 wret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
, 1);
740 /* update the parent key to reflect our changes */
741 struct btrfs_disk_key mid_key
;
742 btrfs_node_key(mid
, &mid_key
, 0);
743 btrfs_set_node_key(parent
, &mid_key
, pslot
);
744 btrfs_mark_buffer_dirty(parent
);
747 /* update the path */
749 if (btrfs_header_nritems(left
) > orig_slot
) {
750 extent_buffer_get(left
);
751 path
->nodes
[level
] = left
;
752 path
->slots
[level
+ 1] -= 1;
753 path
->slots
[level
] = orig_slot
;
755 free_extent_buffer(mid
);
757 orig_slot
-= btrfs_header_nritems(left
);
758 path
->slots
[level
] = orig_slot
;
761 /* double check we haven't messed things up */
762 check_block(root
, path
, level
);
764 btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]))
768 free_extent_buffer(right
);
770 free_extent_buffer(left
);
774 /* returns zero if the push worked, non-zero otherwise */
775 static int push_nodes_for_insert(struct btrfs_trans_handle
*trans
,
776 struct btrfs_root
*root
,
777 struct btrfs_path
*path
, int level
)
779 struct extent_buffer
*right
= NULL
;
780 struct extent_buffer
*mid
;
781 struct extent_buffer
*left
= NULL
;
782 struct extent_buffer
*parent
= NULL
;
786 int orig_slot
= path
->slots
[level
];
792 mid
= path
->nodes
[level
];
793 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
795 if (level
< BTRFS_MAX_LEVEL
- 1)
796 parent
= path
->nodes
[level
+ 1];
797 pslot
= path
->slots
[level
+ 1];
802 left
= read_node_slot(root
, parent
, pslot
- 1);
804 /* first, try to make some room in the middle buffer */
807 left_nr
= btrfs_header_nritems(left
);
808 if (left_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
811 ret
= btrfs_cow_block(trans
, root
, left
, parent
,
816 wret
= push_node_left(trans
, root
,
823 struct btrfs_disk_key disk_key
;
824 orig_slot
+= left_nr
;
825 btrfs_node_key(mid
, &disk_key
, 0);
826 btrfs_set_node_key(parent
, &disk_key
, pslot
);
827 btrfs_mark_buffer_dirty(parent
);
828 if (btrfs_header_nritems(left
) > orig_slot
) {
829 path
->nodes
[level
] = left
;
830 path
->slots
[level
+ 1] -= 1;
831 path
->slots
[level
] = orig_slot
;
832 free_extent_buffer(mid
);
835 btrfs_header_nritems(left
);
836 path
->slots
[level
] = orig_slot
;
837 free_extent_buffer(left
);
841 free_extent_buffer(left
);
843 right
= read_node_slot(root
, parent
, pslot
+ 1);
846 * then try to empty the right most buffer into the middle
850 right_nr
= btrfs_header_nritems(right
);
851 if (right_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
854 ret
= btrfs_cow_block(trans
, root
, right
,
860 wret
= balance_node_right(trans
, root
,
867 struct btrfs_disk_key disk_key
;
869 btrfs_node_key(right
, &disk_key
, 0);
870 btrfs_set_node_key(parent
, &disk_key
, pslot
+ 1);
871 btrfs_mark_buffer_dirty(parent
);
873 if (btrfs_header_nritems(mid
) <= orig_slot
) {
874 path
->nodes
[level
] = right
;
875 path
->slots
[level
+ 1] += 1;
876 path
->slots
[level
] = orig_slot
-
877 btrfs_header_nritems(mid
);
878 free_extent_buffer(mid
);
880 free_extent_buffer(right
);
884 free_extent_buffer(right
);
890 * readahead one full node of leaves
892 static void reada_for_search(struct btrfs_root
*root
, struct btrfs_path
*path
,
897 struct extent_buffer
*node
;
905 int direction
= path
->reada
;
907 struct radix_tree_root found
;
908 unsigned long gang
[8];
909 struct extent_buffer
*eb
;
915 if (!path
->nodes
[level
])
918 node
= path
->nodes
[level
];
919 search
= btrfs_node_blockptr(node
, slot
);
920 eb
= btrfs_find_tree_block(root
, search
);
922 free_extent_buffer(eb
);
926 init_bit_radix(&found
);
927 nritems
= btrfs_header_nritems(node
);
928 level
= btrfs_header_level(node
) - 1;
929 for (i
= slot
; i
< nritems
; i
++) {
930 bytenr
= btrfs_node_blockptr(node
, i
);
931 set_radix_bit(&found
, blocknr
);
934 cluster_start
= search
- 4;
935 if (cluster_start
> search
)
938 cluster_start
= search
+ 4;
940 ret
= find_first_radix_bit(&found
, gang
, 0, ARRAY_SIZE(gang
));
943 for (i
= 0; i
< ret
; i
++) {
945 clear_radix_bit(&found
, blocknr
);
946 if (path
->reada
== 1 && nread
> 16)
948 if (close_blocks(cluster_start
, blocknr
)) {
949 readahead_tree_block(root
, blocknr
);
951 cluster_start
= blocknr
;
958 * look for key in the tree. path is filled in with nodes along the way
959 * if key is found, we return zero and you can find the item in the leaf
960 * level of the path (level 0)
962 * If the key isn't found, the path points to the slot where it should
963 * be inserted, and 1 is returned. If there are other errors during the
964 * search a negative error number is returned.
966 * if ins_len > 0, nodes and leaves will be split as we walk down the
967 * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
970 int btrfs_search_slot(struct btrfs_trans_handle
*trans
, struct btrfs_root
971 *root
, struct btrfs_key
*key
, struct btrfs_path
*p
, int
974 struct extent_buffer
*b
;
979 int should_reada
= p
->reada
;
982 lowest_level
= p
->lowest_level
;
983 WARN_ON(lowest_level
&& ins_len
);
984 WARN_ON(p
->nodes
[0] != NULL
);
985 WARN_ON(!mutex_is_locked(&root
->fs_info
->fs_mutex
));
988 extent_buffer_get(b
);
990 level
= btrfs_header_level(b
);
993 wret
= btrfs_cow_block(trans
, root
, b
,
998 free_extent_buffer(b
);
1002 BUG_ON(!cow
&& ins_len
);
1003 if (level
!= btrfs_header_level(b
))
1005 level
= btrfs_header_level(b
);
1006 p
->nodes
[level
] = b
;
1007 ret
= check_block(root
, p
, level
);
1010 ret
= bin_search(b
, key
, level
, &slot
);
1012 if (ret
&& slot
> 0)
1014 p
->slots
[level
] = slot
;
1015 if (ins_len
> 0 && btrfs_header_nritems(b
) >=
1016 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
1017 int sret
= split_node(trans
, root
, p
, level
);
1021 b
= p
->nodes
[level
];
1022 slot
= p
->slots
[level
];
1023 } else if (ins_len
< 0) {
1024 int sret
= balance_level(trans
, root
, p
,
1028 b
= p
->nodes
[level
];
1030 btrfs_release_path(NULL
, p
);
1033 slot
= p
->slots
[level
];
1034 BUG_ON(btrfs_header_nritems(b
) == 1);
1036 /* this is only true while dropping a snapshot */
1037 if (level
== lowest_level
)
1039 bytenr
= btrfs_node_blockptr(b
, slot
);
1041 reada_for_search(root
, p
, level
, slot
);
1042 b
= read_tree_block(root
, bytenr
,
1043 btrfs_level_size(root
, level
- 1));
1045 p
->slots
[level
] = slot
;
1046 if (ins_len
> 0 && btrfs_leaf_free_space(root
, b
) <
1047 sizeof(struct btrfs_item
) + ins_len
) {
1048 int sret
= split_leaf(trans
, root
, key
,
1061 * adjust the pointers going up the tree, starting at level
1062 * making sure the right key of each node is points to 'key'.
1063 * This is used after shifting pointers to the left, so it stops
1064 * fixing up pointers when a given leaf/node is not in slot 0 of the
1067 * If this fails to write a tree block, it returns -1, but continues
1068 * fixing up the blocks in ram so the tree is consistent.
1070 static int fixup_low_keys(struct btrfs_trans_handle
*trans
,
1071 struct btrfs_root
*root
, struct btrfs_path
*path
,
1072 struct btrfs_disk_key
*key
, int level
)
1076 struct extent_buffer
*t
;
1078 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1079 int tslot
= path
->slots
[i
];
1080 if (!path
->nodes
[i
])
1083 btrfs_set_node_key(t
, key
, tslot
);
1084 btrfs_mark_buffer_dirty(path
->nodes
[i
]);
1092 * try to push data from one node into the next node left in the
1095 * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
1096 * error, and > 0 if there was no room in the left hand block.
1098 static int push_node_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1099 *root
, struct extent_buffer
*dst
,
1100 struct extent_buffer
*src
)
1107 src_nritems
= btrfs_header_nritems(src
);
1108 dst_nritems
= btrfs_header_nritems(dst
);
1109 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1111 if (push_items
<= 0) {
1115 if (src_nritems
< push_items
)
1116 push_items
= src_nritems
;
1118 copy_extent_buffer(dst
, src
,
1119 btrfs_node_key_ptr_offset(dst_nritems
),
1120 btrfs_node_key_ptr_offset(0),
1121 push_items
* sizeof(struct btrfs_key_ptr
));
1123 if (push_items
< src_nritems
) {
1124 memmove_extent_buffer(src
, btrfs_node_key_ptr_offset(0),
1125 btrfs_node_key_ptr_offset(push_items
),
1126 (src_nritems
- push_items
) *
1127 sizeof(struct btrfs_key_ptr
));
1129 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1130 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1131 btrfs_mark_buffer_dirty(src
);
1132 btrfs_mark_buffer_dirty(dst
);
1137 * try to push data from one node into the next node right in the
1140 * returns 0 if some ptrs were pushed, < 0 if there was some horrible
1141 * error, and > 0 if there was no room in the right hand block.
1143 * this will only push up to 1/2 the contents of the left node over
1145 static int balance_node_right(struct btrfs_trans_handle
*trans
,
1146 struct btrfs_root
*root
,
1147 struct extent_buffer
*dst
,
1148 struct extent_buffer
*src
)
1156 src_nritems
= btrfs_header_nritems(src
);
1157 dst_nritems
= btrfs_header_nritems(dst
);
1158 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1159 if (push_items
<= 0)
1162 max_push
= src_nritems
/ 2 + 1;
1163 /* don't try to empty the node */
1164 if (max_push
>= src_nritems
)
1167 if (max_push
< push_items
)
1168 push_items
= max_push
;
1170 memmove_extent_buffer(dst
, btrfs_node_key_ptr_offset(push_items
),
1171 btrfs_node_key_ptr_offset(0),
1173 sizeof(struct btrfs_key_ptr
));
1175 copy_extent_buffer(dst
, src
,
1176 btrfs_node_key_ptr_offset(0),
1177 btrfs_node_key_ptr_offset(src_nritems
- push_items
),
1178 push_items
* sizeof(struct btrfs_key_ptr
));
1180 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1181 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1183 btrfs_mark_buffer_dirty(src
);
1184 btrfs_mark_buffer_dirty(dst
);
1189 * helper function to insert a new root level in the tree.
1190 * A new node is allocated, and a single item is inserted to
1191 * point to the existing root
1193 * returns zero on success or < 0 on failure.
1195 static int insert_new_root(struct btrfs_trans_handle
*trans
,
1196 struct btrfs_root
*root
,
1197 struct btrfs_path
*path
, int level
)
1199 struct extent_buffer
*lower
;
1200 struct extent_buffer
*c
;
1201 struct btrfs_disk_key lower_key
;
1203 BUG_ON(path
->nodes
[level
]);
1204 BUG_ON(path
->nodes
[level
-1] != root
->node
);
1206 c
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1207 root
->node
->start
, 0);
1210 memset_extent_buffer(c
, 0, 0, root
->nodesize
);
1211 btrfs_set_header_nritems(c
, 1);
1212 btrfs_set_header_level(c
, level
);
1213 btrfs_set_header_bytenr(c
, c
->start
);
1214 btrfs_set_header_generation(c
, trans
->transid
);
1215 btrfs_set_header_owner(c
, root
->root_key
.objectid
);
1216 lower
= path
->nodes
[level
-1];
1218 write_extent_buffer(c
, root
->fs_info
->fsid
,
1219 (unsigned long)btrfs_header_fsid(c
),
1222 btrfs_item_key(lower
, &lower_key
, 0);
1224 btrfs_node_key(lower
, &lower_key
, 0);
1225 btrfs_set_node_key(c
, &lower_key
, 0);
1226 btrfs_set_node_blockptr(c
, 0, lower
->start
);
1228 btrfs_mark_buffer_dirty(c
);
1230 /* the super has an extra ref to root->node */
1231 free_extent_buffer(root
->node
);
1233 extent_buffer_get(c
);
1234 path
->nodes
[level
] = c
;
1235 path
->slots
[level
] = 0;
1240 * worker function to insert a single pointer in a node.
1241 * the node should have enough room for the pointer already
1243 * slot and level indicate where you want the key to go, and
1244 * blocknr is the block the key points to.
1246 * returns zero on success and < 0 on any error
1248 static int insert_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
1249 *root
, struct btrfs_path
*path
, struct btrfs_disk_key
1250 *key
, u64 bytenr
, int slot
, int level
)
1252 struct extent_buffer
*lower
;
1255 BUG_ON(!path
->nodes
[level
]);
1256 lower
= path
->nodes
[level
];
1257 nritems
= btrfs_header_nritems(lower
);
1260 if (nritems
== BTRFS_NODEPTRS_PER_BLOCK(root
))
1262 if (slot
!= nritems
) {
1263 memmove_extent_buffer(lower
,
1264 btrfs_node_key_ptr_offset(slot
+ 1),
1265 btrfs_node_key_ptr_offset(slot
),
1266 (nritems
- slot
) * sizeof(struct btrfs_key_ptr
));
1268 btrfs_set_node_key(lower
, key
, slot
);
1269 btrfs_set_node_blockptr(lower
, slot
, bytenr
);
1270 btrfs_set_header_nritems(lower
, nritems
+ 1);
1271 btrfs_mark_buffer_dirty(lower
);
1276 * split the node at the specified level in path in two.
1277 * The path is corrected to point to the appropriate node after the split
1279 * Before splitting this tries to make some room in the node by pushing
1280 * left and right, if either one works, it returns right away.
1282 * returns 0 on success and < 0 on failure
1284 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
1285 *root
, struct btrfs_path
*path
, int level
)
1287 struct extent_buffer
*c
;
1288 struct extent_buffer
*split
;
1289 struct btrfs_disk_key disk_key
;
1295 c
= path
->nodes
[level
];
1296 if (c
== root
->node
) {
1297 /* trying to split the root, lets make a new one */
1298 ret
= insert_new_root(trans
, root
, path
, level
+ 1);
1302 ret
= push_nodes_for_insert(trans
, root
, path
, level
);
1303 c
= path
->nodes
[level
];
1304 if (!ret
&& btrfs_header_nritems(c
) <
1305 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1)
1311 c_nritems
= btrfs_header_nritems(c
);
1312 split
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1315 return PTR_ERR(split
);
1317 btrfs_set_header_flags(split
, btrfs_header_flags(c
));
1318 btrfs_set_header_level(split
, btrfs_header_level(c
));
1319 btrfs_set_header_bytenr(split
, split
->start
);
1320 btrfs_set_header_generation(split
, trans
->transid
);
1321 btrfs_set_header_owner(split
, root
->root_key
.objectid
);
1322 write_extent_buffer(split
, root
->fs_info
->fsid
,
1323 (unsigned long)btrfs_header_fsid(split
),
1326 mid
= (c_nritems
+ 1) / 2;
1328 copy_extent_buffer(split
, c
,
1329 btrfs_node_key_ptr_offset(0),
1330 btrfs_node_key_ptr_offset(mid
),
1331 (c_nritems
- mid
) * sizeof(struct btrfs_key_ptr
));
1332 btrfs_set_header_nritems(split
, c_nritems
- mid
);
1333 btrfs_set_header_nritems(c
, mid
);
1336 btrfs_mark_buffer_dirty(c
);
1337 btrfs_mark_buffer_dirty(split
);
1339 btrfs_node_key(split
, &disk_key
, 0);
1340 wret
= insert_ptr(trans
, root
, path
, &disk_key
, split
->start
,
1341 path
->slots
[level
+ 1] + 1,
1346 if (path
->slots
[level
] >= mid
) {
1347 path
->slots
[level
] -= mid
;
1348 free_extent_buffer(c
);
1349 path
->nodes
[level
] = split
;
1350 path
->slots
[level
+ 1] += 1;
1352 free_extent_buffer(split
);
1358 * how many bytes are required to store the items in a leaf. start
1359 * and nr indicate which items in the leaf to check. This totals up the
1360 * space used both by the item structs and the item data
1362 static int leaf_space_used(struct extent_buffer
*l
, int start
, int nr
)
1365 int nritems
= btrfs_header_nritems(l
);
1366 int end
= min(nritems
, start
+ nr
) - 1;
1370 data_len
= btrfs_item_end_nr(l
, start
);
1371 data_len
= data_len
- btrfs_item_offset_nr(l
, end
);
1372 data_len
+= sizeof(struct btrfs_item
) * nr
;
1373 WARN_ON(data_len
< 0);
1378 * The space between the end of the leaf items and
1379 * the start of the leaf data. IOW, how much room
1380 * the leaf has left for both items and data
1382 int btrfs_leaf_free_space(struct btrfs_root
*root
, struct extent_buffer
*leaf
)
1384 int nritems
= btrfs_header_nritems(leaf
);
1386 ret
= BTRFS_LEAF_DATA_SIZE(root
) - leaf_space_used(leaf
, 0, nritems
);
1388 printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
1389 ret
, BTRFS_LEAF_DATA_SIZE(root
),
1390 leaf_space_used(leaf
, 0, nritems
), nritems
);
1396 * push some data in the path leaf to the right, trying to free up at
1397 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1399 * returns 1 if the push failed because the other node didn't have enough
1400 * room, 0 if everything worked out and < 0 if there were major errors.
1402 static int push_leaf_right(struct btrfs_trans_handle
*trans
, struct btrfs_root
1403 *root
, struct btrfs_path
*path
, int data_size
)
1405 struct extent_buffer
*left
= path
->nodes
[0];
1406 struct extent_buffer
*right
;
1407 struct extent_buffer
*upper
;
1408 struct btrfs_disk_key disk_key
;
1414 struct btrfs_item
*item
;
1421 slot
= path
->slots
[1];
1422 if (!path
->nodes
[1]) {
1425 upper
= path
->nodes
[1];
1426 if (slot
>= btrfs_header_nritems(upper
) - 1)
1429 right
= read_tree_block(root
, btrfs_node_blockptr(upper
, slot
+ 1),
1431 free_space
= btrfs_leaf_free_space(root
, right
);
1432 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1433 free_extent_buffer(right
);
1437 /* cow and double check */
1438 ret
= btrfs_cow_block(trans
, root
, right
, upper
,
1441 free_extent_buffer(right
);
1444 free_space
= btrfs_leaf_free_space(root
, right
);
1445 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1446 free_extent_buffer(right
);
1450 left_nritems
= btrfs_header_nritems(left
);
1451 if (left_nritems
== 0) {
1452 free_extent_buffer(right
);
1456 for (i
= left_nritems
- 1; i
>= 1; i
--) {
1457 item
= btrfs_item_nr(left
, i
);
1459 if (path
->slots
[0] == i
)
1460 push_space
+= data_size
+ sizeof(*item
);
1462 if (!left
->map_token
) {
1463 map_extent_buffer(left
, (unsigned long)item
,
1464 sizeof(struct btrfs_item
),
1465 &left
->map_token
, &left
->kaddr
,
1466 &left
->map_start
, &left
->map_len
,
1470 this_item_size
= btrfs_item_size(left
, item
);
1471 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1474 push_space
+= this_item_size
+ sizeof(*item
);
1476 if (left
->map_token
) {
1477 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1478 left
->map_token
= NULL
;
1481 if (push_items
== 0) {
1482 free_extent_buffer(right
);
1486 if (push_items
== left_nritems
)
1489 /* push left to right */
1490 right_nritems
= btrfs_header_nritems(right
);
1491 push_space
= btrfs_item_end_nr(left
, left_nritems
- push_items
);
1492 push_space
-= leaf_data_end(root
, left
);
1494 /* make room in the right data area */
1495 data_end
= leaf_data_end(root
, right
);
1496 memmove_extent_buffer(right
,
1497 btrfs_leaf_data(right
) + data_end
- push_space
,
1498 btrfs_leaf_data(right
) + data_end
,
1499 BTRFS_LEAF_DATA_SIZE(root
) - data_end
);
1501 /* copy from the left data area */
1502 copy_extent_buffer(right
, left
, btrfs_leaf_data(right
) +
1503 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1504 btrfs_leaf_data(left
) + leaf_data_end(root
, left
),
1507 memmove_extent_buffer(right
, btrfs_item_nr_offset(push_items
),
1508 btrfs_item_nr_offset(0),
1509 right_nritems
* sizeof(struct btrfs_item
));
1511 /* copy the items from left to right */
1512 copy_extent_buffer(right
, left
, btrfs_item_nr_offset(0),
1513 btrfs_item_nr_offset(left_nritems
- push_items
),
1514 push_items
* sizeof(struct btrfs_item
));
1516 /* update the item pointers */
1517 right_nritems
+= push_items
;
1518 btrfs_set_header_nritems(right
, right_nritems
);
1519 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1521 for (i
= 0; i
< right_nritems
; i
++) {
1522 item
= btrfs_item_nr(right
, i
);
1523 if (!right
->map_token
) {
1524 map_extent_buffer(right
, (unsigned long)item
,
1525 sizeof(struct btrfs_item
),
1526 &right
->map_token
, &right
->kaddr
,
1527 &right
->map_start
, &right
->map_len
,
1530 push_space
-= btrfs_item_size(right
, item
);
1531 btrfs_set_item_offset(right
, item
, push_space
);
1534 if (right
->map_token
) {
1535 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1536 right
->map_token
= NULL
;
1538 left_nritems
-= push_items
;
1539 btrfs_set_header_nritems(left
, left_nritems
);
1541 btrfs_mark_buffer_dirty(left
);
1542 btrfs_mark_buffer_dirty(right
);
1544 btrfs_item_key(right
, &disk_key
, 0);
1545 btrfs_set_node_key(upper
, &disk_key
, slot
+ 1);
1546 btrfs_mark_buffer_dirty(upper
);
1548 /* then fixup the leaf pointer in the path */
1549 if (path
->slots
[0] >= left_nritems
) {
1550 path
->slots
[0] -= left_nritems
;
1551 free_extent_buffer(path
->nodes
[0]);
1552 path
->nodes
[0] = right
;
1553 path
->slots
[1] += 1;
1555 free_extent_buffer(right
);
1560 * push some data in the path leaf to the left, trying to free up at
1561 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1563 static int push_leaf_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1564 *root
, struct btrfs_path
*path
, int data_size
)
1566 struct btrfs_disk_key disk_key
;
1567 struct extent_buffer
*right
= path
->nodes
[0];
1568 struct extent_buffer
*left
;
1574 struct btrfs_item
*item
;
1575 u32 old_left_nritems
;
1580 u32 old_left_item_size
;
1582 slot
= path
->slots
[1];
1585 if (!path
->nodes
[1])
1588 left
= read_tree_block(root
, btrfs_node_blockptr(path
->nodes
[1],
1589 slot
- 1), root
->leafsize
);
1590 free_space
= btrfs_leaf_free_space(root
, left
);
1591 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1592 free_extent_buffer(left
);
1596 /* cow and double check */
1597 ret
= btrfs_cow_block(trans
, root
, left
,
1598 path
->nodes
[1], slot
- 1, &left
);
1600 /* we hit -ENOSPC, but it isn't fatal here */
1601 free_extent_buffer(left
);
1604 free_space
= btrfs_leaf_free_space(root
, left
);
1605 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1606 free_extent_buffer(left
);
1610 right_nritems
= btrfs_header_nritems(right
);
1611 if (right_nritems
== 0) {
1612 free_extent_buffer(left
);
1616 for (i
= 0; i
< right_nritems
- 1; i
++) {
1617 item
= btrfs_item_nr(right
, i
);
1618 if (!right
->map_token
) {
1619 map_extent_buffer(right
, (unsigned long)item
,
1620 sizeof(struct btrfs_item
),
1621 &right
->map_token
, &right
->kaddr
,
1622 &right
->map_start
, &right
->map_len
,
1626 if (path
->slots
[0] == i
)
1627 push_space
+= data_size
+ sizeof(*item
);
1629 this_item_size
= btrfs_item_size(right
, item
);
1630 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1634 push_space
+= this_item_size
+ sizeof(*item
);
1637 if (right
->map_token
) {
1638 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1639 right
->map_token
= NULL
;
1642 if (push_items
== 0) {
1643 free_extent_buffer(left
);
1646 if (push_items
== btrfs_header_nritems(right
))
1649 /* push data from right to left */
1650 copy_extent_buffer(left
, right
,
1651 btrfs_item_nr_offset(btrfs_header_nritems(left
)),
1652 btrfs_item_nr_offset(0),
1653 push_items
* sizeof(struct btrfs_item
));
1655 push_space
= BTRFS_LEAF_DATA_SIZE(root
) -
1656 btrfs_item_offset_nr(right
, push_items
-1);
1658 copy_extent_buffer(left
, right
, btrfs_leaf_data(left
) +
1659 leaf_data_end(root
, left
) - push_space
,
1660 btrfs_leaf_data(right
) +
1661 btrfs_item_offset_nr(right
, push_items
- 1),
1663 old_left_nritems
= btrfs_header_nritems(left
);
1664 BUG_ON(old_left_nritems
< 0);
1666 old_left_item_size
= btrfs_item_offset_nr(left
, old_left_nritems
- 1);
1667 for (i
= old_left_nritems
; i
< old_left_nritems
+ push_items
; i
++) {
1670 item
= btrfs_item_nr(left
, i
);
1671 if (!left
->map_token
) {
1672 map_extent_buffer(left
, (unsigned long)item
,
1673 sizeof(struct btrfs_item
),
1674 &left
->map_token
, &left
->kaddr
,
1675 &left
->map_start
, &left
->map_len
,
1679 ioff
= btrfs_item_offset(left
, item
);
1680 btrfs_set_item_offset(left
, item
,
1681 ioff
- (BTRFS_LEAF_DATA_SIZE(root
) - old_left_item_size
));
1683 btrfs_set_header_nritems(left
, old_left_nritems
+ push_items
);
1684 if (left
->map_token
) {
1685 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1686 left
->map_token
= NULL
;
1689 /* fixup right node */
1690 push_space
= btrfs_item_offset_nr(right
, push_items
- 1) -
1691 leaf_data_end(root
, right
);
1692 memmove_extent_buffer(right
, btrfs_leaf_data(right
) +
1693 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1694 btrfs_leaf_data(right
) +
1695 leaf_data_end(root
, right
), push_space
);
1697 memmove_extent_buffer(right
, btrfs_item_nr_offset(0),
1698 btrfs_item_nr_offset(push_items
),
1699 (btrfs_header_nritems(right
) - push_items
) *
1700 sizeof(struct btrfs_item
));
1702 right_nritems
= btrfs_header_nritems(right
) - push_items
;
1703 btrfs_set_header_nritems(right
, right_nritems
);
1704 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1706 for (i
= 0; i
< right_nritems
; i
++) {
1707 item
= btrfs_item_nr(right
, i
);
1709 if (!right
->map_token
) {
1710 map_extent_buffer(right
, (unsigned long)item
,
1711 sizeof(struct btrfs_item
),
1712 &right
->map_token
, &right
->kaddr
,
1713 &right
->map_start
, &right
->map_len
,
1717 push_space
= push_space
- btrfs_item_size(right
, item
);
1718 btrfs_set_item_offset(right
, item
, push_space
);
1720 if (right
->map_token
) {
1721 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1722 right
->map_token
= NULL
;
1725 btrfs_mark_buffer_dirty(left
);
1726 btrfs_mark_buffer_dirty(right
);
1728 btrfs_item_key(right
, &disk_key
, 0);
1729 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1733 /* then fixup the leaf pointer in the path */
1734 if (path
->slots
[0] < push_items
) {
1735 path
->slots
[0] += old_left_nritems
;
1736 free_extent_buffer(path
->nodes
[0]);
1737 path
->nodes
[0] = left
;
1738 path
->slots
[1] -= 1;
1740 free_extent_buffer(left
);
1741 path
->slots
[0] -= push_items
;
1743 BUG_ON(path
->slots
[0] < 0);
1748 * split the path's leaf in two, making sure there is at least data_size
1749 * available for the resulting leaf level of the path.
1751 * returns 0 if all went well and < 0 on failure.
1753 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
1754 *root
, struct btrfs_key
*ins_key
,
1755 struct btrfs_path
*path
, int data_size
)
1757 struct extent_buffer
*l
;
1761 struct extent_buffer
*right
;
1762 int space_needed
= data_size
+ sizeof(struct btrfs_item
);
1768 int double_split
= 0;
1769 struct btrfs_disk_key disk_key
;
1771 /* first try to make some room by pushing left and right */
1772 wret
= push_leaf_left(trans
, root
, path
, data_size
);
1776 wret
= push_leaf_right(trans
, root
, path
, data_size
);
1782 /* did the pushes work? */
1783 if (btrfs_leaf_free_space(root
, l
) >=
1784 sizeof(struct btrfs_item
) + data_size
)
1787 if (!path
->nodes
[1]) {
1788 ret
= insert_new_root(trans
, root
, path
, 1);
1792 slot
= path
->slots
[0];
1793 nritems
= btrfs_header_nritems(l
);
1794 mid
= (nritems
+ 1)/ 2;
1796 right
= btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
1799 return PTR_ERR(right
);
1801 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
1802 btrfs_set_header_bytenr(right
, right
->start
);
1803 btrfs_set_header_generation(right
, trans
->transid
);
1804 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
1805 btrfs_set_header_level(right
, 0);
1806 write_extent_buffer(right
, root
->fs_info
->fsid
,
1807 (unsigned long)btrfs_header_fsid(right
),
1812 leaf_space_used(l
, mid
, nritems
- mid
) + space_needed
>
1813 BTRFS_LEAF_DATA_SIZE(root
)) {
1814 if (slot
>= nritems
) {
1815 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1816 btrfs_set_header_nritems(right
, 0);
1817 wret
= insert_ptr(trans
, root
, path
,
1818 &disk_key
, right
->start
,
1819 path
->slots
[1] + 1, 1);
1822 free_extent_buffer(path
->nodes
[0]);
1823 path
->nodes
[0] = right
;
1825 path
->slots
[1] += 1;
1832 if (leaf_space_used(l
, 0, mid
+ 1) + space_needed
>
1833 BTRFS_LEAF_DATA_SIZE(root
)) {
1835 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1836 btrfs_set_header_nritems(right
, 0);
1837 wret
= insert_ptr(trans
, root
, path
,
1843 free_extent_buffer(path
->nodes
[0]);
1844 path
->nodes
[0] = right
;
1846 if (path
->slots
[1] == 0) {
1847 wret
= fixup_low_keys(trans
, root
,
1848 path
, &disk_key
, 1);
1858 nritems
= nritems
- mid
;
1859 btrfs_set_header_nritems(right
, nritems
);
1860 data_copy_size
= btrfs_item_end_nr(l
, mid
) - leaf_data_end(root
, l
);
1862 copy_extent_buffer(right
, l
, btrfs_item_nr_offset(0),
1863 btrfs_item_nr_offset(mid
),
1864 nritems
* sizeof(struct btrfs_item
));
1866 copy_extent_buffer(right
, l
,
1867 btrfs_leaf_data(right
) + BTRFS_LEAF_DATA_SIZE(root
) -
1868 data_copy_size
, btrfs_leaf_data(l
) +
1869 leaf_data_end(root
, l
), data_copy_size
);
1871 rt_data_off
= BTRFS_LEAF_DATA_SIZE(root
) -
1872 btrfs_item_end_nr(l
, mid
);
1874 for (i
= 0; i
< nritems
; i
++) {
1875 struct btrfs_item
*item
= btrfs_item_nr(right
, i
);
1878 if (!right
->map_token
) {
1879 map_extent_buffer(right
, (unsigned long)item
,
1880 sizeof(struct btrfs_item
),
1881 &right
->map_token
, &right
->kaddr
,
1882 &right
->map_start
, &right
->map_len
,
1886 ioff
= btrfs_item_offset(right
, item
);
1887 btrfs_set_item_offset(right
, item
, ioff
+ rt_data_off
);
1890 if (right
->map_token
) {
1891 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1892 right
->map_token
= NULL
;
1895 btrfs_set_header_nritems(l
, mid
);
1897 btrfs_item_key(right
, &disk_key
, 0);
1898 wret
= insert_ptr(trans
, root
, path
, &disk_key
, right
->start
,
1899 path
->slots
[1] + 1, 1);
1903 btrfs_mark_buffer_dirty(right
);
1904 btrfs_mark_buffer_dirty(l
);
1905 BUG_ON(path
->slots
[0] != slot
);
1908 free_extent_buffer(path
->nodes
[0]);
1909 path
->nodes
[0] = right
;
1910 path
->slots
[0] -= mid
;
1911 path
->slots
[1] += 1;
1913 free_extent_buffer(right
);
1915 BUG_ON(path
->slots
[0] < 0);
1920 right
= btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
1923 return PTR_ERR(right
);
1925 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
1926 btrfs_set_header_bytenr(right
, right
->start
);
1927 btrfs_set_header_generation(right
, trans
->transid
);
1928 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
1929 btrfs_set_header_level(right
, 0);
1930 write_extent_buffer(right
, root
->fs_info
->fsid
,
1931 (unsigned long)btrfs_header_fsid(right
),
1934 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1935 btrfs_set_header_nritems(right
, 0);
1936 wret
= insert_ptr(trans
, root
, path
,
1937 &disk_key
, right
->start
,
1941 if (path
->slots
[1] == 0) {
1942 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1946 free_extent_buffer(path
->nodes
[0]);
1947 path
->nodes
[0] = right
;
1952 int btrfs_truncate_item(struct btrfs_trans_handle
*trans
,
1953 struct btrfs_root
*root
,
1954 struct btrfs_path
*path
,
1960 struct extent_buffer
*leaf
;
1961 struct btrfs_item
*item
;
1963 unsigned int data_end
;
1964 unsigned int old_data_start
;
1965 unsigned int old_size
;
1966 unsigned int size_diff
;
1969 slot_orig
= path
->slots
[0];
1970 leaf
= path
->nodes
[0];
1972 nritems
= btrfs_header_nritems(leaf
);
1973 data_end
= leaf_data_end(root
, leaf
);
1975 slot
= path
->slots
[0];
1976 old_data_start
= btrfs_item_offset_nr(leaf
, slot
);
1977 old_size
= btrfs_item_size_nr(leaf
, slot
);
1978 BUG_ON(old_size
<= new_size
);
1979 size_diff
= old_size
- new_size
;
1982 BUG_ON(slot
>= nritems
);
1985 * item0..itemN ... dataN.offset..dataN.size .. data0.size
1987 /* first correct the data pointers */
1988 for (i
= slot
; i
< nritems
; i
++) {
1990 item
= btrfs_item_nr(leaf
, i
);
1992 if (!leaf
->map_token
) {
1993 map_extent_buffer(leaf
, (unsigned long)item
,
1994 sizeof(struct btrfs_item
),
1995 &leaf
->map_token
, &leaf
->kaddr
,
1996 &leaf
->map_start
, &leaf
->map_len
,
2000 ioff
= btrfs_item_offset(leaf
, item
);
2001 btrfs_set_item_offset(leaf
, item
, ioff
+ size_diff
);
2004 if (leaf
->map_token
) {
2005 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2006 leaf
->map_token
= NULL
;
2009 /* shift the data */
2010 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2011 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2012 data_end
, old_data_start
+ new_size
- data_end
);
2014 item
= btrfs_item_nr(leaf
, slot
);
2015 btrfs_set_item_size(leaf
, item
, new_size
);
2016 btrfs_mark_buffer_dirty(leaf
);
2019 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2020 btrfs_print_leaf(root
, leaf
);
2026 int btrfs_extend_item(struct btrfs_trans_handle
*trans
,
2027 struct btrfs_root
*root
, struct btrfs_path
*path
,
2033 struct extent_buffer
*leaf
;
2034 struct btrfs_item
*item
;
2036 unsigned int data_end
;
2037 unsigned int old_data
;
2038 unsigned int old_size
;
2041 slot_orig
= path
->slots
[0];
2042 leaf
= path
->nodes
[0];
2044 nritems
= btrfs_header_nritems(leaf
);
2045 data_end
= leaf_data_end(root
, leaf
);
2047 if (btrfs_leaf_free_space(root
, leaf
) < data_size
) {
2048 btrfs_print_leaf(root
, leaf
);
2051 slot
= path
->slots
[0];
2052 old_data
= btrfs_item_end_nr(leaf
, slot
);
2055 BUG_ON(slot
>= nritems
);
2058 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2060 /* first correct the data pointers */
2061 for (i
= slot
; i
< nritems
; i
++) {
2063 item
= btrfs_item_nr(leaf
, i
);
2065 if (!leaf
->map_token
) {
2066 map_extent_buffer(leaf
, (unsigned long)item
,
2067 sizeof(struct btrfs_item
),
2068 &leaf
->map_token
, &leaf
->kaddr
,
2069 &leaf
->map_start
, &leaf
->map_len
,
2072 ioff
= btrfs_item_offset(leaf
, item
);
2073 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2076 if (leaf
->map_token
) {
2077 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2078 leaf
->map_token
= NULL
;
2081 /* shift the data */
2082 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2083 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2084 data_end
, old_data
- data_end
);
2086 data_end
= old_data
;
2087 old_size
= btrfs_item_size_nr(leaf
, slot
);
2088 item
= btrfs_item_nr(leaf
, slot
);
2089 btrfs_set_item_size(leaf
, item
, old_size
+ data_size
);
2090 btrfs_mark_buffer_dirty(leaf
);
2093 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2094 btrfs_print_leaf(root
, leaf
);
2101 * Given a key and some data, insert an item into the tree.
2102 * This does all the path init required, making room in the tree if needed.
2104 int btrfs_insert_empty_item(struct btrfs_trans_handle
*trans
,
2105 struct btrfs_root
*root
,
2106 struct btrfs_path
*path
,
2107 struct btrfs_key
*cpu_key
, u32 data_size
)
2109 struct extent_buffer
*leaf
;
2110 struct btrfs_item
*item
;
2115 unsigned int data_end
;
2116 struct btrfs_disk_key disk_key
;
2118 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
);
2120 /* create a root if there isn't one */
2124 ret
= btrfs_search_slot(trans
, root
, cpu_key
, path
, data_size
, 1);
2131 slot_orig
= path
->slots
[0];
2132 leaf
= path
->nodes
[0];
2134 nritems
= btrfs_header_nritems(leaf
);
2135 data_end
= leaf_data_end(root
, leaf
);
2137 if (btrfs_leaf_free_space(root
, leaf
) <
2138 sizeof(struct btrfs_item
) + data_size
) {
2142 slot
= path
->slots
[0];
2145 if (slot
!= nritems
) {
2147 unsigned int old_data
= btrfs_item_end_nr(leaf
, slot
);
2149 if (old_data
< data_end
) {
2150 btrfs_print_leaf(root
, leaf
);
2151 printk("slot %d old_data %d data_end %d\n",
2152 slot
, old_data
, data_end
);
2156 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2158 /* first correct the data pointers */
2159 WARN_ON(leaf
->map_token
);
2160 for (i
= slot
; i
< nritems
; i
++) {
2163 item
= btrfs_item_nr(leaf
, i
);
2164 if (!leaf
->map_token
) {
2165 map_extent_buffer(leaf
, (unsigned long)item
,
2166 sizeof(struct btrfs_item
),
2167 &leaf
->map_token
, &leaf
->kaddr
,
2168 &leaf
->map_start
, &leaf
->map_len
,
2172 ioff
= btrfs_item_offset(leaf
, item
);
2173 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2175 if (leaf
->map_token
) {
2176 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2177 leaf
->map_token
= NULL
;
2180 /* shift the items */
2181 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ 1),
2182 btrfs_item_nr_offset(slot
),
2183 (nritems
- slot
) * sizeof(struct btrfs_item
));
2185 /* shift the data */
2186 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2187 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2188 data_end
, old_data
- data_end
);
2189 data_end
= old_data
;
2192 /* setup the item for the new data */
2193 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2194 item
= btrfs_item_nr(leaf
, slot
);
2195 btrfs_set_item_offset(leaf
, item
, data_end
- data_size
);
2196 btrfs_set_item_size(leaf
, item
, data_size
);
2197 btrfs_set_header_nritems(leaf
, nritems
+ 1);
2198 btrfs_mark_buffer_dirty(leaf
);
2202 ret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2204 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2205 btrfs_print_leaf(root
, leaf
);
2213 * Given a key and some data, insert an item into the tree.
2214 * This does all the path init required, making room in the tree if needed.
2216 int btrfs_insert_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
2217 *root
, struct btrfs_key
*cpu_key
, void *data
, u32
2221 struct btrfs_path
*path
;
2222 struct extent_buffer
*leaf
;
2225 path
= btrfs_alloc_path();
2227 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
2229 leaf
= path
->nodes
[0];
2230 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2231 write_extent_buffer(leaf
, data
, ptr
, data_size
);
2232 btrfs_mark_buffer_dirty(leaf
);
2234 btrfs_free_path(path
);
2239 * delete the pointer from a given node.
2241 * If the delete empties a node, the node is removed from the tree,
2242 * continuing all the way the root if required. The root is converted into
2243 * a leaf if all the nodes are emptied.
2245 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2246 struct btrfs_path
*path
, int level
, int slot
)
2248 struct extent_buffer
*parent
= path
->nodes
[level
];
2253 nritems
= btrfs_header_nritems(parent
);
2254 if (slot
!= nritems
-1) {
2255 memmove_extent_buffer(parent
,
2256 btrfs_node_key_ptr_offset(slot
),
2257 btrfs_node_key_ptr_offset(slot
+ 1),
2258 sizeof(struct btrfs_key_ptr
) *
2259 (nritems
- slot
- 1));
2262 btrfs_set_header_nritems(parent
, nritems
);
2263 if (nritems
== 0 && parent
== root
->node
) {
2264 BUG_ON(btrfs_header_level(root
->node
) != 1);
2265 /* just turn the root into a leaf and break */
2266 btrfs_set_header_level(root
->node
, 0);
2267 } else if (slot
== 0) {
2268 struct btrfs_disk_key disk_key
;
2270 btrfs_node_key(parent
, &disk_key
, 0);
2271 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, level
+ 1);
2275 btrfs_mark_buffer_dirty(parent
);
2280 * delete the item at the leaf level in path. If that empties
2281 * the leaf, remove it from the tree
2283 int btrfs_del_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2284 struct btrfs_path
*path
)
2287 struct extent_buffer
*leaf
;
2288 struct btrfs_item
*item
;
2295 leaf
= path
->nodes
[0];
2296 slot
= path
->slots
[0];
2297 doff
= btrfs_item_offset_nr(leaf
, slot
);
2298 dsize
= btrfs_item_size_nr(leaf
, slot
);
2299 nritems
= btrfs_header_nritems(leaf
);
2301 if (slot
!= nritems
- 1) {
2303 int data_end
= leaf_data_end(root
, leaf
);
2305 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2307 btrfs_leaf_data(leaf
) + data_end
,
2310 for (i
= slot
+ 1; i
< nritems
; i
++) {
2313 item
= btrfs_item_nr(leaf
, i
);
2314 if (!leaf
->map_token
) {
2315 map_extent_buffer(leaf
, (unsigned long)item
,
2316 sizeof(struct btrfs_item
),
2317 &leaf
->map_token
, &leaf
->kaddr
,
2318 &leaf
->map_start
, &leaf
->map_len
,
2321 ioff
= btrfs_item_offset(leaf
, item
);
2322 btrfs_set_item_offset(leaf
, item
, ioff
+ dsize
);
2325 if (leaf
->map_token
) {
2326 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2327 leaf
->map_token
= NULL
;
2330 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
),
2331 btrfs_item_nr_offset(slot
+ 1),
2332 sizeof(struct btrfs_item
) *
2333 (nritems
- slot
- 1));
2335 btrfs_set_header_nritems(leaf
, nritems
- 1);
2338 /* delete the leaf if we've emptied it */
2340 if (leaf
== root
->node
) {
2341 btrfs_set_header_level(leaf
, 0);
2343 clean_tree_block(trans
, root
, leaf
);
2344 wait_on_tree_block_writeback(root
, leaf
);
2345 wret
= del_ptr(trans
, root
, path
, 1, path
->slots
[1]);
2348 wret
= btrfs_free_extent(trans
, root
,
2349 leaf
->start
, leaf
->len
, 1);
2354 int used
= leaf_space_used(leaf
, 0, nritems
);
2356 struct btrfs_disk_key disk_key
;
2358 btrfs_item_key(leaf
, &disk_key
, 0);
2359 wret
= fixup_low_keys(trans
, root
, path
,
2365 /* delete the leaf if it is mostly empty */
2366 if (used
< BTRFS_LEAF_DATA_SIZE(root
) / 3) {
2367 /* push_leaf_left fixes the path.
2368 * make sure the path still points to our leaf
2369 * for possible call to del_ptr below
2371 slot
= path
->slots
[1];
2372 extent_buffer_get(leaf
);
2374 wret
= push_leaf_left(trans
, root
, path
, 1);
2375 if (wret
< 0 && wret
!= -ENOSPC
)
2378 if (path
->nodes
[0] == leaf
&&
2379 btrfs_header_nritems(leaf
)) {
2380 wret
= push_leaf_right(trans
, root
, path
, 1);
2381 if (wret
< 0 && wret
!= -ENOSPC
)
2385 if (btrfs_header_nritems(leaf
) == 0) {
2386 u64 bytenr
= leaf
->start
;
2387 u32 blocksize
= leaf
->len
;
2389 clean_tree_block(trans
, root
, leaf
);
2390 wait_on_tree_block_writeback(root
, leaf
);
2392 wret
= del_ptr(trans
, root
, path
, 1, slot
);
2396 free_extent_buffer(leaf
);
2397 wret
= btrfs_free_extent(trans
, root
, bytenr
,
2402 btrfs_mark_buffer_dirty(leaf
);
2403 free_extent_buffer(leaf
);
2406 btrfs_mark_buffer_dirty(leaf
);
2413 * walk up the tree as far as required to find the next leaf.
2414 * returns 0 if it found something or 1 if there are no greater leaves.
2415 * returns < 0 on io errors.
2417 int btrfs_next_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2422 struct extent_buffer
*c
;
2423 struct extent_buffer
*next
= NULL
;
2425 while(level
< BTRFS_MAX_LEVEL
) {
2426 if (!path
->nodes
[level
])
2429 slot
= path
->slots
[level
] + 1;
2430 c
= path
->nodes
[level
];
2431 if (slot
>= btrfs_header_nritems(c
)) {
2436 bytenr
= btrfs_node_blockptr(c
, slot
);
2438 free_extent_buffer(next
);
2441 reada_for_search(root
, path
, level
, slot
);
2443 next
= read_tree_block(root
, bytenr
,
2444 btrfs_level_size(root
, level
-1));
2447 path
->slots
[level
] = slot
;
2450 c
= path
->nodes
[level
];
2451 free_extent_buffer(c
);
2452 path
->nodes
[level
] = next
;
2453 path
->slots
[level
] = 0;
2457 reada_for_search(root
, path
, level
, 0);
2458 next
= read_tree_block(root
, btrfs_node_blockptr(next
, 0),
2459 btrfs_level_size(root
, level
- 1));