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 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
92 btrfs_set_header_bytenr(cow
, cow
->start
);
93 btrfs_set_header_generation(cow
, trans
->transid
);
94 btrfs_set_header_owner(cow
, root
->root_key
.objectid
);
96 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
97 if (btrfs_header_generation(buf
) != trans
->transid
) {
99 ret
= btrfs_inc_ref(trans
, root
, buf
);
103 clean_tree_block(trans
, root
, buf
);
106 if (buf
== root
->node
) {
108 extent_buffer_get(cow
);
109 if (buf
!= root
->commit_root
) {
110 btrfs_free_extent(trans
, root
, buf
->start
,
113 free_extent_buffer(buf
);
115 btrfs_set_node_blockptr(parent
, parent_slot
,
117 btrfs_mark_buffer_dirty(parent
);
118 WARN_ON(btrfs_header_generation(parent
) != trans
->transid
);
119 btrfs_free_extent(trans
, root
, buf
->start
, buf
->len
, 1);
121 free_extent_buffer(buf
);
122 btrfs_mark_buffer_dirty(cow
);
127 int btrfs_cow_block(struct btrfs_trans_handle
*trans
,
128 struct btrfs_root
*root
, struct extent_buffer
*buf
,
129 struct extent_buffer
*parent
, int parent_slot
,
130 struct extent_buffer
**cow_ret
)
134 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
135 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
136 root
->fs_info
->running_transaction
->transid
);
139 if (trans
->transid
!= root
->fs_info
->generation
) {
140 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
141 root
->fs_info
->generation
);
144 if (btrfs_header_generation(buf
) == trans
->transid
) {
149 search_start
= buf
->start
& ~((u64
)BTRFS_BLOCK_GROUP_SIZE
- 1);
150 ret
= __btrfs_cow_block(trans
, root
, buf
, parent
,
151 parent_slot
, cow_ret
, search_start
, 0);
155 static int close_blocks(u64 blocknr
, u64 other
, u32 blocksize
)
157 if (blocknr
< other
&& other
- (blocknr
+ blocksize
) < 32768)
159 if (blocknr
> other
&& blocknr
- (other
+ blocksize
) < 32768)
164 static int should_defrag_leaf(struct extent_buffer
*leaf
)
166 struct btrfs_key key
;
169 if (btrfs_buffer_defrag(leaf
))
172 nritems
= btrfs_header_nritems(leaf
);
176 btrfs_item_key_to_cpu(leaf
, &key
, 0);
177 if (key
.type
== BTRFS_DIR_ITEM_KEY
)
181 btrfs_item_key_to_cpu(leaf
, &key
, nritems
- 1);
182 if (key
.type
== BTRFS_DIR_ITEM_KEY
)
185 btrfs_item_key_to_cpu(leaf
, &key
, nritems
/ 2);
186 if (key
.type
== BTRFS_DIR_ITEM_KEY
)
192 int btrfs_realloc_node(struct btrfs_trans_handle
*trans
,
193 struct btrfs_root
*root
, struct extent_buffer
*parent
,
194 int cache_only
, u64
*last_ret
)
196 struct extent_buffer
*cur
;
197 struct extent_buffer
*tmp
;
199 u64 search_start
= *last_ret
;
211 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
212 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
213 root
->fs_info
->running_transaction
->transid
);
216 if (trans
->transid
!= root
->fs_info
->generation
) {
217 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
218 root
->fs_info
->generation
);
221 if (btrfs_buffer_defrag_done(parent
))
224 parent_nritems
= btrfs_header_nritems(parent
);
225 parent_level
= btrfs_header_level(parent
);
226 blocksize
= btrfs_level_size(root
, parent_level
- 1);
229 end_slot
= parent_nritems
;
231 if (parent_nritems
== 1)
234 for (i
= start_slot
; i
< end_slot
; i
++) {
236 blocknr
= btrfs_node_blockptr(parent
, i
);
238 last_block
= blocknr
;
240 other
= btrfs_node_blockptr(parent
, i
- 1);
241 close
= close_blocks(blocknr
, other
, blocksize
);
243 if (close
&& i
< end_slot
- 1) {
244 other
= btrfs_node_blockptr(parent
, i
+ 1);
245 close
= close_blocks(blocknr
, other
, blocksize
);
248 last_block
= blocknr
;
252 cur
= btrfs_find_tree_block(root
, blocknr
, blocksize
);
254 uptodate
= btrfs_buffer_uptodate(cur
);
257 if (!cur
|| !uptodate
||
258 (parent_level
!= 1 && !btrfs_buffer_defrag(cur
)) ||
259 (parent_level
== 1 && !should_defrag_leaf(cur
))) {
261 free_extent_buffer(cur
);
265 cur
= read_tree_block(root
, blocknr
,
267 } else if (!uptodate
) {
268 btrfs_read_buffer(cur
);
271 if (search_start
== 0)
272 search_start
= last_block
;
274 err
= __btrfs_cow_block(trans
, root
, cur
, parent
, i
,
277 (end_slot
- i
) * blocksize
));
279 free_extent_buffer(cur
);
282 search_start
= tmp
->start
;
283 *last_ret
= search_start
;
284 if (parent_level
== 1)
285 btrfs_clear_buffer_defrag(tmp
);
286 btrfs_set_buffer_defrag_done(tmp
);
287 free_extent_buffer(tmp
);
293 * The leaf data grows from end-to-front in the node.
294 * this returns the address of the start of the last item,
295 * which is the stop of the leaf data stack
297 static inline unsigned int leaf_data_end(struct btrfs_root
*root
,
298 struct extent_buffer
*leaf
)
300 u32 nr
= btrfs_header_nritems(leaf
);
302 return BTRFS_LEAF_DATA_SIZE(root
);
303 return btrfs_item_offset_nr(leaf
, nr
- 1);
307 * compare two keys in a memcmp fashion
309 static int comp_keys(struct btrfs_disk_key
*disk
, struct btrfs_key
*k2
)
313 btrfs_disk_key_to_cpu(&k1
, disk
);
315 if (k1
.objectid
> k2
->objectid
)
317 if (k1
.objectid
< k2
->objectid
)
319 if (k1
.type
> k2
->type
)
321 if (k1
.type
< k2
->type
)
323 if (k1
.offset
> k2
->offset
)
325 if (k1
.offset
< k2
->offset
)
330 static int check_node(struct btrfs_root
*root
, struct btrfs_path
*path
,
333 struct extent_buffer
*parent
= NULL
;
334 struct extent_buffer
*node
= path
->nodes
[level
];
335 struct btrfs_disk_key parent_key
;
336 struct btrfs_disk_key node_key
;
339 struct btrfs_key cpukey
;
340 u32 nritems
= btrfs_header_nritems(node
);
342 if (path
->nodes
[level
+ 1])
343 parent
= path
->nodes
[level
+ 1];
345 slot
= path
->slots
[level
];
346 BUG_ON(nritems
== 0);
348 parent_slot
= path
->slots
[level
+ 1];
349 btrfs_node_key(parent
, &parent_key
, parent_slot
);
350 btrfs_node_key(node
, &node_key
, 0);
351 BUG_ON(memcmp(&parent_key
, &node_key
,
352 sizeof(struct btrfs_disk_key
)));
353 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
354 btrfs_header_bytenr(node
));
356 BUG_ON(nritems
> BTRFS_NODEPTRS_PER_BLOCK(root
));
358 btrfs_node_key_to_cpu(node
, &cpukey
, slot
- 1);
359 btrfs_node_key(node
, &node_key
, slot
);
360 BUG_ON(comp_keys(&node_key
, &cpukey
) <= 0);
362 if (slot
< nritems
- 1) {
363 btrfs_node_key_to_cpu(node
, &cpukey
, slot
+ 1);
364 btrfs_node_key(node
, &node_key
, slot
);
365 BUG_ON(comp_keys(&node_key
, &cpukey
) >= 0);
370 static int check_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
,
373 struct extent_buffer
*leaf
= path
->nodes
[level
];
374 struct extent_buffer
*parent
= NULL
;
376 struct btrfs_key cpukey
;
377 struct btrfs_disk_key parent_key
;
378 struct btrfs_disk_key leaf_key
;
379 int slot
= path
->slots
[0];
381 u32 nritems
= btrfs_header_nritems(leaf
);
383 if (path
->nodes
[level
+ 1])
384 parent
= path
->nodes
[level
+ 1];
390 parent_slot
= path
->slots
[level
+ 1];
391 btrfs_node_key(parent
, &parent_key
, parent_slot
);
392 btrfs_item_key(leaf
, &leaf_key
, 0);
394 BUG_ON(memcmp(&parent_key
, &leaf_key
,
395 sizeof(struct btrfs_disk_key
)));
396 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
397 btrfs_header_bytenr(leaf
));
400 for (i
= 0; nritems
> 1 && i
< nritems
- 2; i
++) {
401 btrfs_item_key_to_cpu(leaf
, &cpukey
, i
+ 1);
402 btrfs_item_key(leaf
, &leaf_key
, i
);
403 if (comp_keys(&leaf_key
, &cpukey
) >= 0) {
404 btrfs_print_leaf(root
, leaf
);
405 printk("slot %d offset bad key\n", i
);
408 if (btrfs_item_offset_nr(leaf
, i
) !=
409 btrfs_item_end_nr(leaf
, i
+ 1)) {
410 btrfs_print_leaf(root
, leaf
);
411 printk("slot %d offset bad\n", i
);
415 if (btrfs_item_offset_nr(leaf
, i
) +
416 btrfs_item_size_nr(leaf
, i
) !=
417 BTRFS_LEAF_DATA_SIZE(root
)) {
418 btrfs_print_leaf(root
, leaf
);
419 printk("slot %d first offset bad\n", i
);
425 if (btrfs_item_size_nr(leaf
, nritems
- 1) > 4096) {
426 btrfs_print_leaf(root
, leaf
);
427 printk("slot %d bad size \n", nritems
- 1);
432 if (slot
!= 0 && slot
< nritems
- 1) {
433 btrfs_item_key(leaf
, &leaf_key
, slot
);
434 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
- 1);
435 if (comp_keys(&leaf_key
, &cpukey
) <= 0) {
436 btrfs_print_leaf(root
, leaf
);
437 printk("slot %d offset bad key\n", slot
);
440 if (btrfs_item_offset_nr(leaf
, slot
- 1) !=
441 btrfs_item_end_nr(leaf
, slot
)) {
442 btrfs_print_leaf(root
, leaf
);
443 printk("slot %d offset bad\n", slot
);
447 if (slot
< nritems
- 1) {
448 btrfs_item_key(leaf
, &leaf_key
, slot
);
449 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
+ 1);
450 BUG_ON(comp_keys(&leaf_key
, &cpukey
) >= 0);
451 if (btrfs_item_offset_nr(leaf
, slot
) !=
452 btrfs_item_end_nr(leaf
, slot
+ 1)) {
453 btrfs_print_leaf(root
, leaf
);
454 printk("slot %d offset bad\n", slot
);
458 BUG_ON(btrfs_item_offset_nr(leaf
, 0) +
459 btrfs_item_size_nr(leaf
, 0) != BTRFS_LEAF_DATA_SIZE(root
));
463 static int check_block(struct btrfs_root
*root
, struct btrfs_path
*path
,
467 struct extent_buffer
*buf
= path
->nodes
[level
];
469 if (memcmp_extent_buffer(buf
, root
->fs_info
->fsid
,
470 (unsigned long)btrfs_header_fsid(buf
),
472 printk("warning bad block %Lu\n", buf
->start
);
477 return check_leaf(root
, path
, level
);
478 return check_node(root
, path
, level
);
482 * search for key in the extent_buffer. The items start at offset p,
483 * and they are item_size apart. There are 'max' items in p.
485 * the slot in the array is returned via slot, and it points to
486 * the place where you would insert key if it is not found in
489 * slot may point to max if the key is bigger than all of the keys
491 static int generic_bin_search(struct extent_buffer
*eb
, unsigned long p
,
492 int item_size
, struct btrfs_key
*key
,
499 struct btrfs_disk_key
*tmp
= NULL
;
500 struct btrfs_disk_key unaligned
;
501 unsigned long offset
;
502 char *map_token
= NULL
;
504 unsigned long map_start
= 0;
505 unsigned long map_len
= 0;
509 mid
= (low
+ high
) / 2;
510 offset
= p
+ mid
* item_size
;
512 if (!map_token
|| offset
< map_start
||
513 (offset
+ sizeof(struct btrfs_disk_key
)) >
514 map_start
+ map_len
) {
516 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
519 err
= map_extent_buffer(eb
, offset
,
520 sizeof(struct btrfs_disk_key
),
522 &map_start
, &map_len
, KM_USER0
);
525 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
528 read_extent_buffer(eb
, &unaligned
,
529 offset
, sizeof(unaligned
));
534 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
537 ret
= comp_keys(tmp
, key
);
546 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
552 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
557 * simple bin_search frontend that does the right thing for
560 static int bin_search(struct extent_buffer
*eb
, struct btrfs_key
*key
,
561 int level
, int *slot
)
564 return generic_bin_search(eb
,
565 offsetof(struct btrfs_leaf
, items
),
566 sizeof(struct btrfs_item
),
567 key
, btrfs_header_nritems(eb
),
570 return generic_bin_search(eb
,
571 offsetof(struct btrfs_node
, ptrs
),
572 sizeof(struct btrfs_key_ptr
),
573 key
, btrfs_header_nritems(eb
),
579 static struct extent_buffer
*read_node_slot(struct btrfs_root
*root
,
580 struct extent_buffer
*parent
, int slot
)
584 if (slot
>= btrfs_header_nritems(parent
))
586 return read_tree_block(root
, btrfs_node_blockptr(parent
, slot
),
587 btrfs_level_size(root
, btrfs_header_level(parent
) - 1));
590 static int balance_level(struct btrfs_trans_handle
*trans
, struct btrfs_root
591 *root
, struct btrfs_path
*path
, int level
)
593 struct extent_buffer
*right
= NULL
;
594 struct extent_buffer
*mid
;
595 struct extent_buffer
*left
= NULL
;
596 struct extent_buffer
*parent
= NULL
;
600 int orig_slot
= path
->slots
[level
];
601 int err_on_enospc
= 0;
607 mid
= path
->nodes
[level
];
608 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
610 if (level
< BTRFS_MAX_LEVEL
- 1)
611 parent
= path
->nodes
[level
+ 1];
612 pslot
= path
->slots
[level
+ 1];
615 * deal with the case where there is only one pointer in the root
616 * by promoting the node below to a root
619 struct extent_buffer
*child
;
621 if (btrfs_header_nritems(mid
) != 1)
624 /* promote the child to a root */
625 child
= read_node_slot(root
, mid
, 0);
628 path
->nodes
[level
] = NULL
;
629 clean_tree_block(trans
, root
, mid
);
630 wait_on_tree_block_writeback(root
, mid
);
631 /* once for the path */
632 free_extent_buffer(mid
);
633 ret
= btrfs_free_extent(trans
, root
, mid
->start
, mid
->len
, 1);
634 /* once for the root ptr */
635 free_extent_buffer(mid
);
638 if (btrfs_header_nritems(mid
) >
639 BTRFS_NODEPTRS_PER_BLOCK(root
) / 4)
642 if (btrfs_header_nritems(mid
) < 2)
645 left
= read_node_slot(root
, parent
, pslot
- 1);
647 wret
= btrfs_cow_block(trans
, root
, left
,
648 parent
, pslot
- 1, &left
);
654 right
= read_node_slot(root
, parent
, pslot
+ 1);
656 wret
= btrfs_cow_block(trans
, root
, right
,
657 parent
, pslot
+ 1, &right
);
664 /* first, try to make some room in the middle buffer */
666 orig_slot
+= btrfs_header_nritems(left
);
667 wret
= push_node_left(trans
, root
, left
, mid
);
670 if (btrfs_header_nritems(mid
) < 2)
675 * then try to empty the right most buffer into the middle
678 wret
= push_node_left(trans
, root
, mid
, right
);
679 if (wret
< 0 && wret
!= -ENOSPC
)
681 if (btrfs_header_nritems(right
) == 0) {
682 u64 bytenr
= right
->start
;
683 u32 blocksize
= right
->len
;
685 clean_tree_block(trans
, root
, right
);
686 wait_on_tree_block_writeback(root
, right
);
687 free_extent_buffer(right
);
689 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
+
693 wret
= btrfs_free_extent(trans
, root
, bytenr
,
698 struct btrfs_disk_key right_key
;
699 btrfs_node_key(right
, &right_key
, 0);
700 btrfs_set_node_key(parent
, &right_key
, pslot
+ 1);
701 btrfs_mark_buffer_dirty(parent
);
704 if (btrfs_header_nritems(mid
) == 1) {
706 * we're not allowed to leave a node with one item in the
707 * tree during a delete. A deletion from lower in the tree
708 * could try to delete the only pointer in this node.
709 * So, pull some keys from the left.
710 * There has to be a left pointer at this point because
711 * otherwise we would have pulled some pointers from the
715 wret
= balance_node_right(trans
, root
, mid
, left
);
722 if (btrfs_header_nritems(mid
) == 0) {
723 /* we've managed to empty the middle node, drop it */
724 u64 bytenr
= mid
->start
;
725 u32 blocksize
= mid
->len
;
726 clean_tree_block(trans
, root
, mid
);
727 wait_on_tree_block_writeback(root
, mid
);
728 free_extent_buffer(mid
);
730 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
);
733 wret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
, 1);
737 /* update the parent key to reflect our changes */
738 struct btrfs_disk_key mid_key
;
739 btrfs_node_key(mid
, &mid_key
, 0);
740 btrfs_set_node_key(parent
, &mid_key
, pslot
);
741 btrfs_mark_buffer_dirty(parent
);
744 /* update the path */
746 if (btrfs_header_nritems(left
) > orig_slot
) {
747 extent_buffer_get(left
);
748 path
->nodes
[level
] = left
;
749 path
->slots
[level
+ 1] -= 1;
750 path
->slots
[level
] = orig_slot
;
752 free_extent_buffer(mid
);
754 orig_slot
-= btrfs_header_nritems(left
);
755 path
->slots
[level
] = orig_slot
;
758 /* double check we haven't messed things up */
759 check_block(root
, path
, level
);
761 btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]))
765 free_extent_buffer(right
);
767 free_extent_buffer(left
);
771 /* returns zero if the push worked, non-zero otherwise */
772 static int push_nodes_for_insert(struct btrfs_trans_handle
*trans
,
773 struct btrfs_root
*root
,
774 struct btrfs_path
*path
, int level
)
776 struct extent_buffer
*right
= NULL
;
777 struct extent_buffer
*mid
;
778 struct extent_buffer
*left
= NULL
;
779 struct extent_buffer
*parent
= NULL
;
783 int orig_slot
= path
->slots
[level
];
789 mid
= path
->nodes
[level
];
790 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
792 if (level
< BTRFS_MAX_LEVEL
- 1)
793 parent
= path
->nodes
[level
+ 1];
794 pslot
= path
->slots
[level
+ 1];
799 left
= read_node_slot(root
, parent
, pslot
- 1);
801 /* first, try to make some room in the middle buffer */
804 left_nr
= btrfs_header_nritems(left
);
805 if (left_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
808 ret
= btrfs_cow_block(trans
, root
, left
, parent
,
813 wret
= push_node_left(trans
, root
,
820 struct btrfs_disk_key disk_key
;
821 orig_slot
+= left_nr
;
822 btrfs_node_key(mid
, &disk_key
, 0);
823 btrfs_set_node_key(parent
, &disk_key
, pslot
);
824 btrfs_mark_buffer_dirty(parent
);
825 if (btrfs_header_nritems(left
) > orig_slot
) {
826 path
->nodes
[level
] = left
;
827 path
->slots
[level
+ 1] -= 1;
828 path
->slots
[level
] = orig_slot
;
829 free_extent_buffer(mid
);
832 btrfs_header_nritems(left
);
833 path
->slots
[level
] = orig_slot
;
834 free_extent_buffer(left
);
838 free_extent_buffer(left
);
840 right
= read_node_slot(root
, parent
, pslot
+ 1);
843 * then try to empty the right most buffer into the middle
847 right_nr
= btrfs_header_nritems(right
);
848 if (right_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
851 ret
= btrfs_cow_block(trans
, root
, right
,
857 wret
= balance_node_right(trans
, root
,
864 struct btrfs_disk_key disk_key
;
866 btrfs_node_key(right
, &disk_key
, 0);
867 btrfs_set_node_key(parent
, &disk_key
, pslot
+ 1);
868 btrfs_mark_buffer_dirty(parent
);
870 if (btrfs_header_nritems(mid
) <= orig_slot
) {
871 path
->nodes
[level
] = right
;
872 path
->slots
[level
+ 1] += 1;
873 path
->slots
[level
] = orig_slot
-
874 btrfs_header_nritems(mid
);
875 free_extent_buffer(mid
);
877 free_extent_buffer(right
);
881 free_extent_buffer(right
);
887 * readahead one full node of leaves
889 static void reada_for_search(struct btrfs_root
*root
, struct btrfs_path
*path
,
892 struct extent_buffer
*node
;
898 int direction
= path
->reada
;
899 struct extent_buffer
*eb
;
907 if (!path
->nodes
[level
])
910 node
= path
->nodes
[level
];
911 search
= btrfs_node_blockptr(node
, slot
);
912 blocksize
= btrfs_level_size(root
, level
- 1);
913 eb
= btrfs_find_tree_block(root
, search
, blocksize
);
915 free_extent_buffer(eb
);
919 highest_read
= search
;
920 lowest_read
= search
;
922 nritems
= btrfs_header_nritems(node
);
929 } else if (direction
> 0) {
934 search
= btrfs_node_blockptr(node
, nr
);
935 if ((search
>= lowest_read
&& search
<= highest_read
) ||
936 (search
< lowest_read
&& lowest_read
- search
<= 32768) ||
937 (search
> highest_read
&& search
- highest_read
<= 32768)) {
938 readahead_tree_block(root
, search
, blocksize
);
942 if (path
->reada
< 2 && (nread
> (256 * 1024) || nscan
> 32))
944 if(nread
> (1024 * 1024) || nscan
> 128)
947 if (search
< lowest_read
)
948 lowest_read
= search
;
949 if (search
> highest_read
)
950 highest_read
= search
;
954 * look for key in the tree. path is filled in with nodes along the way
955 * if key is found, we return zero and you can find the item in the leaf
956 * level of the path (level 0)
958 * If the key isn't found, the path points to the slot where it should
959 * be inserted, and 1 is returned. If there are other errors during the
960 * search a negative error number is returned.
962 * if ins_len > 0, nodes and leaves will be split as we walk down the
963 * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
966 int btrfs_search_slot(struct btrfs_trans_handle
*trans
, struct btrfs_root
967 *root
, struct btrfs_key
*key
, struct btrfs_path
*p
, int
970 struct extent_buffer
*b
;
975 int should_reada
= p
->reada
;
978 lowest_level
= p
->lowest_level
;
979 WARN_ON(lowest_level
&& ins_len
);
980 WARN_ON(p
->nodes
[0] != NULL
);
981 WARN_ON(!mutex_is_locked(&root
->fs_info
->fs_mutex
));
984 extent_buffer_get(b
);
986 level
= btrfs_header_level(b
);
989 wret
= btrfs_cow_block(trans
, root
, b
,
994 free_extent_buffer(b
);
998 BUG_ON(!cow
&& ins_len
);
999 if (level
!= btrfs_header_level(b
))
1001 level
= btrfs_header_level(b
);
1002 p
->nodes
[level
] = b
;
1003 ret
= check_block(root
, p
, level
);
1006 ret
= bin_search(b
, key
, level
, &slot
);
1008 if (ret
&& slot
> 0)
1010 p
->slots
[level
] = slot
;
1011 if (ins_len
> 0 && btrfs_header_nritems(b
) >=
1012 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
1013 int sret
= split_node(trans
, root
, p
, level
);
1017 b
= p
->nodes
[level
];
1018 slot
= p
->slots
[level
];
1019 } else if (ins_len
< 0) {
1020 int sret
= balance_level(trans
, root
, p
,
1024 b
= p
->nodes
[level
];
1026 btrfs_release_path(NULL
, p
);
1029 slot
= p
->slots
[level
];
1030 BUG_ON(btrfs_header_nritems(b
) == 1);
1032 /* this is only true while dropping a snapshot */
1033 if (level
== lowest_level
)
1035 bytenr
= btrfs_node_blockptr(b
, slot
);
1037 reada_for_search(root
, p
, level
, slot
);
1038 b
= read_tree_block(root
, bytenr
,
1039 btrfs_level_size(root
, level
- 1));
1041 p
->slots
[level
] = slot
;
1042 if (ins_len
> 0 && btrfs_leaf_free_space(root
, b
) <
1043 sizeof(struct btrfs_item
) + ins_len
) {
1044 int sret
= split_leaf(trans
, root
, key
,
1057 * adjust the pointers going up the tree, starting at level
1058 * making sure the right key of each node is points to 'key'.
1059 * This is used after shifting pointers to the left, so it stops
1060 * fixing up pointers when a given leaf/node is not in slot 0 of the
1063 * If this fails to write a tree block, it returns -1, but continues
1064 * fixing up the blocks in ram so the tree is consistent.
1066 static int fixup_low_keys(struct btrfs_trans_handle
*trans
,
1067 struct btrfs_root
*root
, struct btrfs_path
*path
,
1068 struct btrfs_disk_key
*key
, int level
)
1072 struct extent_buffer
*t
;
1074 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1075 int tslot
= path
->slots
[i
];
1076 if (!path
->nodes
[i
])
1079 btrfs_set_node_key(t
, key
, tslot
);
1080 btrfs_mark_buffer_dirty(path
->nodes
[i
]);
1088 * try to push data from one node into the next node left in the
1091 * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
1092 * error, and > 0 if there was no room in the left hand block.
1094 static int push_node_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1095 *root
, struct extent_buffer
*dst
,
1096 struct extent_buffer
*src
)
1103 src_nritems
= btrfs_header_nritems(src
);
1104 dst_nritems
= btrfs_header_nritems(dst
);
1105 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1107 if (push_items
<= 0) {
1111 if (src_nritems
< push_items
)
1112 push_items
= src_nritems
;
1114 copy_extent_buffer(dst
, src
,
1115 btrfs_node_key_ptr_offset(dst_nritems
),
1116 btrfs_node_key_ptr_offset(0),
1117 push_items
* sizeof(struct btrfs_key_ptr
));
1119 if (push_items
< src_nritems
) {
1120 memmove_extent_buffer(src
, btrfs_node_key_ptr_offset(0),
1121 btrfs_node_key_ptr_offset(push_items
),
1122 (src_nritems
- push_items
) *
1123 sizeof(struct btrfs_key_ptr
));
1125 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1126 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1127 btrfs_mark_buffer_dirty(src
);
1128 btrfs_mark_buffer_dirty(dst
);
1133 * try to push data from one node into the next node right in the
1136 * returns 0 if some ptrs were pushed, < 0 if there was some horrible
1137 * error, and > 0 if there was no room in the right hand block.
1139 * this will only push up to 1/2 the contents of the left node over
1141 static int balance_node_right(struct btrfs_trans_handle
*trans
,
1142 struct btrfs_root
*root
,
1143 struct extent_buffer
*dst
,
1144 struct extent_buffer
*src
)
1152 src_nritems
= btrfs_header_nritems(src
);
1153 dst_nritems
= btrfs_header_nritems(dst
);
1154 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1155 if (push_items
<= 0)
1158 max_push
= src_nritems
/ 2 + 1;
1159 /* don't try to empty the node */
1160 if (max_push
>= src_nritems
)
1163 if (max_push
< push_items
)
1164 push_items
= max_push
;
1166 memmove_extent_buffer(dst
, btrfs_node_key_ptr_offset(push_items
),
1167 btrfs_node_key_ptr_offset(0),
1169 sizeof(struct btrfs_key_ptr
));
1171 copy_extent_buffer(dst
, src
,
1172 btrfs_node_key_ptr_offset(0),
1173 btrfs_node_key_ptr_offset(src_nritems
- push_items
),
1174 push_items
* sizeof(struct btrfs_key_ptr
));
1176 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1177 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1179 btrfs_mark_buffer_dirty(src
);
1180 btrfs_mark_buffer_dirty(dst
);
1185 * helper function to insert a new root level in the tree.
1186 * A new node is allocated, and a single item is inserted to
1187 * point to the existing root
1189 * returns zero on success or < 0 on failure.
1191 static int insert_new_root(struct btrfs_trans_handle
*trans
,
1192 struct btrfs_root
*root
,
1193 struct btrfs_path
*path
, int level
)
1195 struct extent_buffer
*lower
;
1196 struct extent_buffer
*c
;
1197 struct btrfs_disk_key lower_key
;
1199 BUG_ON(path
->nodes
[level
]);
1200 BUG_ON(path
->nodes
[level
-1] != root
->node
);
1202 c
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1203 root
->node
->start
, 0);
1206 memset_extent_buffer(c
, 0, 0, root
->nodesize
);
1207 btrfs_set_header_nritems(c
, 1);
1208 btrfs_set_header_level(c
, level
);
1209 btrfs_set_header_bytenr(c
, c
->start
);
1210 btrfs_set_header_generation(c
, trans
->transid
);
1211 btrfs_set_header_owner(c
, root
->root_key
.objectid
);
1212 lower
= path
->nodes
[level
-1];
1214 write_extent_buffer(c
, root
->fs_info
->fsid
,
1215 (unsigned long)btrfs_header_fsid(c
),
1218 btrfs_item_key(lower
, &lower_key
, 0);
1220 btrfs_node_key(lower
, &lower_key
, 0);
1221 btrfs_set_node_key(c
, &lower_key
, 0);
1222 btrfs_set_node_blockptr(c
, 0, lower
->start
);
1224 btrfs_mark_buffer_dirty(c
);
1226 /* the super has an extra ref to root->node */
1227 free_extent_buffer(root
->node
);
1229 extent_buffer_get(c
);
1230 path
->nodes
[level
] = c
;
1231 path
->slots
[level
] = 0;
1236 * worker function to insert a single pointer in a node.
1237 * the node should have enough room for the pointer already
1239 * slot and level indicate where you want the key to go, and
1240 * blocknr is the block the key points to.
1242 * returns zero on success and < 0 on any error
1244 static int insert_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
1245 *root
, struct btrfs_path
*path
, struct btrfs_disk_key
1246 *key
, u64 bytenr
, int slot
, int level
)
1248 struct extent_buffer
*lower
;
1251 BUG_ON(!path
->nodes
[level
]);
1252 lower
= path
->nodes
[level
];
1253 nritems
= btrfs_header_nritems(lower
);
1256 if (nritems
== BTRFS_NODEPTRS_PER_BLOCK(root
))
1258 if (slot
!= nritems
) {
1259 memmove_extent_buffer(lower
,
1260 btrfs_node_key_ptr_offset(slot
+ 1),
1261 btrfs_node_key_ptr_offset(slot
),
1262 (nritems
- slot
) * sizeof(struct btrfs_key_ptr
));
1264 btrfs_set_node_key(lower
, key
, slot
);
1265 btrfs_set_node_blockptr(lower
, slot
, bytenr
);
1266 btrfs_set_header_nritems(lower
, nritems
+ 1);
1267 btrfs_mark_buffer_dirty(lower
);
1272 * split the node at the specified level in path in two.
1273 * The path is corrected to point to the appropriate node after the split
1275 * Before splitting this tries to make some room in the node by pushing
1276 * left and right, if either one works, it returns right away.
1278 * returns 0 on success and < 0 on failure
1280 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
1281 *root
, struct btrfs_path
*path
, int level
)
1283 struct extent_buffer
*c
;
1284 struct extent_buffer
*split
;
1285 struct btrfs_disk_key disk_key
;
1291 c
= path
->nodes
[level
];
1292 if (c
== root
->node
) {
1293 /* trying to split the root, lets make a new one */
1294 ret
= insert_new_root(trans
, root
, path
, level
+ 1);
1298 ret
= push_nodes_for_insert(trans
, root
, path
, level
);
1299 c
= path
->nodes
[level
];
1300 if (!ret
&& btrfs_header_nritems(c
) <
1301 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1)
1307 c_nritems
= btrfs_header_nritems(c
);
1308 split
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1311 return PTR_ERR(split
);
1313 btrfs_set_header_flags(split
, btrfs_header_flags(c
));
1314 btrfs_set_header_level(split
, btrfs_header_level(c
));
1315 btrfs_set_header_bytenr(split
, split
->start
);
1316 btrfs_set_header_generation(split
, trans
->transid
);
1317 btrfs_set_header_owner(split
, root
->root_key
.objectid
);
1318 write_extent_buffer(split
, root
->fs_info
->fsid
,
1319 (unsigned long)btrfs_header_fsid(split
),
1322 mid
= (c_nritems
+ 1) / 2;
1324 copy_extent_buffer(split
, c
,
1325 btrfs_node_key_ptr_offset(0),
1326 btrfs_node_key_ptr_offset(mid
),
1327 (c_nritems
- mid
) * sizeof(struct btrfs_key_ptr
));
1328 btrfs_set_header_nritems(split
, c_nritems
- mid
);
1329 btrfs_set_header_nritems(c
, mid
);
1332 btrfs_mark_buffer_dirty(c
);
1333 btrfs_mark_buffer_dirty(split
);
1335 btrfs_node_key(split
, &disk_key
, 0);
1336 wret
= insert_ptr(trans
, root
, path
, &disk_key
, split
->start
,
1337 path
->slots
[level
+ 1] + 1,
1342 if (path
->slots
[level
] >= mid
) {
1343 path
->slots
[level
] -= mid
;
1344 free_extent_buffer(c
);
1345 path
->nodes
[level
] = split
;
1346 path
->slots
[level
+ 1] += 1;
1348 free_extent_buffer(split
);
1354 * how many bytes are required to store the items in a leaf. start
1355 * and nr indicate which items in the leaf to check. This totals up the
1356 * space used both by the item structs and the item data
1358 static int leaf_space_used(struct extent_buffer
*l
, int start
, int nr
)
1361 int nritems
= btrfs_header_nritems(l
);
1362 int end
= min(nritems
, start
+ nr
) - 1;
1366 data_len
= btrfs_item_end_nr(l
, start
);
1367 data_len
= data_len
- btrfs_item_offset_nr(l
, end
);
1368 data_len
+= sizeof(struct btrfs_item
) * nr
;
1369 WARN_ON(data_len
< 0);
1374 * The space between the end of the leaf items and
1375 * the start of the leaf data. IOW, how much room
1376 * the leaf has left for both items and data
1378 int btrfs_leaf_free_space(struct btrfs_root
*root
, struct extent_buffer
*leaf
)
1380 int nritems
= btrfs_header_nritems(leaf
);
1382 ret
= BTRFS_LEAF_DATA_SIZE(root
) - leaf_space_used(leaf
, 0, nritems
);
1384 printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
1385 ret
, BTRFS_LEAF_DATA_SIZE(root
),
1386 leaf_space_used(leaf
, 0, nritems
), nritems
);
1392 * push some data in the path leaf to the right, trying to free up at
1393 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1395 * returns 1 if the push failed because the other node didn't have enough
1396 * room, 0 if everything worked out and < 0 if there were major errors.
1398 static int push_leaf_right(struct btrfs_trans_handle
*trans
, struct btrfs_root
1399 *root
, struct btrfs_path
*path
, int data_size
)
1401 struct extent_buffer
*left
= path
->nodes
[0];
1402 struct extent_buffer
*right
;
1403 struct extent_buffer
*upper
;
1404 struct btrfs_disk_key disk_key
;
1410 struct btrfs_item
*item
;
1417 slot
= path
->slots
[1];
1418 if (!path
->nodes
[1]) {
1421 upper
= path
->nodes
[1];
1422 if (slot
>= btrfs_header_nritems(upper
) - 1)
1425 right
= read_tree_block(root
, btrfs_node_blockptr(upper
, slot
+ 1),
1427 free_space
= btrfs_leaf_free_space(root
, right
);
1428 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1429 free_extent_buffer(right
);
1433 /* cow and double check */
1434 ret
= btrfs_cow_block(trans
, root
, right
, upper
,
1437 free_extent_buffer(right
);
1440 free_space
= btrfs_leaf_free_space(root
, right
);
1441 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1442 free_extent_buffer(right
);
1446 left_nritems
= btrfs_header_nritems(left
);
1447 if (left_nritems
== 0) {
1448 free_extent_buffer(right
);
1452 for (i
= left_nritems
- 1; i
>= 1; i
--) {
1453 item
= btrfs_item_nr(left
, i
);
1455 if (path
->slots
[0] == i
)
1456 push_space
+= data_size
+ sizeof(*item
);
1458 if (!left
->map_token
) {
1459 map_extent_buffer(left
, (unsigned long)item
,
1460 sizeof(struct btrfs_item
),
1461 &left
->map_token
, &left
->kaddr
,
1462 &left
->map_start
, &left
->map_len
,
1466 this_item_size
= btrfs_item_size(left
, item
);
1467 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1470 push_space
+= this_item_size
+ sizeof(*item
);
1472 if (left
->map_token
) {
1473 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1474 left
->map_token
= NULL
;
1477 if (push_items
== 0) {
1478 free_extent_buffer(right
);
1482 if (push_items
== left_nritems
)
1485 /* push left to right */
1486 right_nritems
= btrfs_header_nritems(right
);
1487 push_space
= btrfs_item_end_nr(left
, left_nritems
- push_items
);
1488 push_space
-= leaf_data_end(root
, left
);
1490 /* make room in the right data area */
1491 data_end
= leaf_data_end(root
, right
);
1492 memmove_extent_buffer(right
,
1493 btrfs_leaf_data(right
) + data_end
- push_space
,
1494 btrfs_leaf_data(right
) + data_end
,
1495 BTRFS_LEAF_DATA_SIZE(root
) - data_end
);
1497 /* copy from the left data area */
1498 copy_extent_buffer(right
, left
, btrfs_leaf_data(right
) +
1499 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1500 btrfs_leaf_data(left
) + leaf_data_end(root
, left
),
1503 memmove_extent_buffer(right
, btrfs_item_nr_offset(push_items
),
1504 btrfs_item_nr_offset(0),
1505 right_nritems
* sizeof(struct btrfs_item
));
1507 /* copy the items from left to right */
1508 copy_extent_buffer(right
, left
, btrfs_item_nr_offset(0),
1509 btrfs_item_nr_offset(left_nritems
- push_items
),
1510 push_items
* sizeof(struct btrfs_item
));
1512 /* update the item pointers */
1513 right_nritems
+= push_items
;
1514 btrfs_set_header_nritems(right
, right_nritems
);
1515 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1517 for (i
= 0; i
< right_nritems
; i
++) {
1518 item
= btrfs_item_nr(right
, i
);
1519 if (!right
->map_token
) {
1520 map_extent_buffer(right
, (unsigned long)item
,
1521 sizeof(struct btrfs_item
),
1522 &right
->map_token
, &right
->kaddr
,
1523 &right
->map_start
, &right
->map_len
,
1526 push_space
-= btrfs_item_size(right
, item
);
1527 btrfs_set_item_offset(right
, item
, push_space
);
1530 if (right
->map_token
) {
1531 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1532 right
->map_token
= NULL
;
1534 left_nritems
-= push_items
;
1535 btrfs_set_header_nritems(left
, left_nritems
);
1537 btrfs_mark_buffer_dirty(left
);
1538 btrfs_mark_buffer_dirty(right
);
1540 btrfs_item_key(right
, &disk_key
, 0);
1541 btrfs_set_node_key(upper
, &disk_key
, slot
+ 1);
1542 btrfs_mark_buffer_dirty(upper
);
1544 /* then fixup the leaf pointer in the path */
1545 if (path
->slots
[0] >= left_nritems
) {
1546 path
->slots
[0] -= left_nritems
;
1547 free_extent_buffer(path
->nodes
[0]);
1548 path
->nodes
[0] = right
;
1549 path
->slots
[1] += 1;
1551 free_extent_buffer(right
);
1556 * push some data in the path leaf to the left, trying to free up at
1557 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1559 static int push_leaf_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1560 *root
, struct btrfs_path
*path
, int data_size
)
1562 struct btrfs_disk_key disk_key
;
1563 struct extent_buffer
*right
= path
->nodes
[0];
1564 struct extent_buffer
*left
;
1570 struct btrfs_item
*item
;
1571 u32 old_left_nritems
;
1576 u32 old_left_item_size
;
1578 slot
= path
->slots
[1];
1581 if (!path
->nodes
[1])
1584 left
= read_tree_block(root
, btrfs_node_blockptr(path
->nodes
[1],
1585 slot
- 1), root
->leafsize
);
1586 free_space
= btrfs_leaf_free_space(root
, left
);
1587 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1588 free_extent_buffer(left
);
1592 /* cow and double check */
1593 ret
= btrfs_cow_block(trans
, root
, left
,
1594 path
->nodes
[1], slot
- 1, &left
);
1596 /* we hit -ENOSPC, but it isn't fatal here */
1597 free_extent_buffer(left
);
1600 free_space
= btrfs_leaf_free_space(root
, left
);
1601 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1602 free_extent_buffer(left
);
1606 right_nritems
= btrfs_header_nritems(right
);
1607 if (right_nritems
== 0) {
1608 free_extent_buffer(left
);
1612 for (i
= 0; i
< right_nritems
- 1; i
++) {
1613 item
= btrfs_item_nr(right
, i
);
1614 if (!right
->map_token
) {
1615 map_extent_buffer(right
, (unsigned long)item
,
1616 sizeof(struct btrfs_item
),
1617 &right
->map_token
, &right
->kaddr
,
1618 &right
->map_start
, &right
->map_len
,
1622 if (path
->slots
[0] == i
)
1623 push_space
+= data_size
+ sizeof(*item
);
1625 this_item_size
= btrfs_item_size(right
, item
);
1626 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1630 push_space
+= this_item_size
+ sizeof(*item
);
1633 if (right
->map_token
) {
1634 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1635 right
->map_token
= NULL
;
1638 if (push_items
== 0) {
1639 free_extent_buffer(left
);
1642 if (push_items
== btrfs_header_nritems(right
))
1645 /* push data from right to left */
1646 copy_extent_buffer(left
, right
,
1647 btrfs_item_nr_offset(btrfs_header_nritems(left
)),
1648 btrfs_item_nr_offset(0),
1649 push_items
* sizeof(struct btrfs_item
));
1651 push_space
= BTRFS_LEAF_DATA_SIZE(root
) -
1652 btrfs_item_offset_nr(right
, push_items
-1);
1654 copy_extent_buffer(left
, right
, btrfs_leaf_data(left
) +
1655 leaf_data_end(root
, left
) - push_space
,
1656 btrfs_leaf_data(right
) +
1657 btrfs_item_offset_nr(right
, push_items
- 1),
1659 old_left_nritems
= btrfs_header_nritems(left
);
1660 BUG_ON(old_left_nritems
< 0);
1662 old_left_item_size
= btrfs_item_offset_nr(left
, old_left_nritems
- 1);
1663 for (i
= old_left_nritems
; i
< old_left_nritems
+ push_items
; i
++) {
1666 item
= btrfs_item_nr(left
, i
);
1667 if (!left
->map_token
) {
1668 map_extent_buffer(left
, (unsigned long)item
,
1669 sizeof(struct btrfs_item
),
1670 &left
->map_token
, &left
->kaddr
,
1671 &left
->map_start
, &left
->map_len
,
1675 ioff
= btrfs_item_offset(left
, item
);
1676 btrfs_set_item_offset(left
, item
,
1677 ioff
- (BTRFS_LEAF_DATA_SIZE(root
) - old_left_item_size
));
1679 btrfs_set_header_nritems(left
, old_left_nritems
+ push_items
);
1680 if (left
->map_token
) {
1681 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1682 left
->map_token
= NULL
;
1685 /* fixup right node */
1686 push_space
= btrfs_item_offset_nr(right
, push_items
- 1) -
1687 leaf_data_end(root
, right
);
1688 memmove_extent_buffer(right
, btrfs_leaf_data(right
) +
1689 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1690 btrfs_leaf_data(right
) +
1691 leaf_data_end(root
, right
), push_space
);
1693 memmove_extent_buffer(right
, btrfs_item_nr_offset(0),
1694 btrfs_item_nr_offset(push_items
),
1695 (btrfs_header_nritems(right
) - push_items
) *
1696 sizeof(struct btrfs_item
));
1698 right_nritems
= btrfs_header_nritems(right
) - push_items
;
1699 btrfs_set_header_nritems(right
, right_nritems
);
1700 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1702 for (i
= 0; i
< right_nritems
; i
++) {
1703 item
= btrfs_item_nr(right
, i
);
1705 if (!right
->map_token
) {
1706 map_extent_buffer(right
, (unsigned long)item
,
1707 sizeof(struct btrfs_item
),
1708 &right
->map_token
, &right
->kaddr
,
1709 &right
->map_start
, &right
->map_len
,
1713 push_space
= push_space
- btrfs_item_size(right
, item
);
1714 btrfs_set_item_offset(right
, item
, push_space
);
1716 if (right
->map_token
) {
1717 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1718 right
->map_token
= NULL
;
1721 btrfs_mark_buffer_dirty(left
);
1722 btrfs_mark_buffer_dirty(right
);
1724 btrfs_item_key(right
, &disk_key
, 0);
1725 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1729 /* then fixup the leaf pointer in the path */
1730 if (path
->slots
[0] < push_items
) {
1731 path
->slots
[0] += old_left_nritems
;
1732 free_extent_buffer(path
->nodes
[0]);
1733 path
->nodes
[0] = left
;
1734 path
->slots
[1] -= 1;
1736 free_extent_buffer(left
);
1737 path
->slots
[0] -= push_items
;
1739 BUG_ON(path
->slots
[0] < 0);
1744 * split the path's leaf in two, making sure there is at least data_size
1745 * available for the resulting leaf level of the path.
1747 * returns 0 if all went well and < 0 on failure.
1749 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
1750 *root
, struct btrfs_key
*ins_key
,
1751 struct btrfs_path
*path
, int data_size
)
1753 struct extent_buffer
*l
;
1757 struct extent_buffer
*right
;
1758 int space_needed
= data_size
+ sizeof(struct btrfs_item
);
1764 int double_split
= 0;
1765 struct btrfs_disk_key disk_key
;
1767 /* first try to make some room by pushing left and right */
1768 wret
= push_leaf_left(trans
, root
, path
, data_size
);
1772 wret
= push_leaf_right(trans
, root
, path
, data_size
);
1778 /* did the pushes work? */
1779 if (btrfs_leaf_free_space(root
, l
) >=
1780 sizeof(struct btrfs_item
) + data_size
)
1783 if (!path
->nodes
[1]) {
1784 ret
= insert_new_root(trans
, root
, path
, 1);
1788 slot
= path
->slots
[0];
1789 nritems
= btrfs_header_nritems(l
);
1790 mid
= (nritems
+ 1)/ 2;
1792 right
= btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
1795 return PTR_ERR(right
);
1797 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
1798 btrfs_set_header_bytenr(right
, right
->start
);
1799 btrfs_set_header_generation(right
, trans
->transid
);
1800 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
1801 btrfs_set_header_level(right
, 0);
1802 write_extent_buffer(right
, root
->fs_info
->fsid
,
1803 (unsigned long)btrfs_header_fsid(right
),
1808 leaf_space_used(l
, mid
, nritems
- mid
) + space_needed
>
1809 BTRFS_LEAF_DATA_SIZE(root
)) {
1810 if (slot
>= nritems
) {
1811 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1812 btrfs_set_header_nritems(right
, 0);
1813 wret
= insert_ptr(trans
, root
, path
,
1814 &disk_key
, right
->start
,
1815 path
->slots
[1] + 1, 1);
1818 free_extent_buffer(path
->nodes
[0]);
1819 path
->nodes
[0] = right
;
1821 path
->slots
[1] += 1;
1828 if (leaf_space_used(l
, 0, mid
+ 1) + space_needed
>
1829 BTRFS_LEAF_DATA_SIZE(root
)) {
1831 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1832 btrfs_set_header_nritems(right
, 0);
1833 wret
= insert_ptr(trans
, root
, path
,
1839 free_extent_buffer(path
->nodes
[0]);
1840 path
->nodes
[0] = right
;
1842 if (path
->slots
[1] == 0) {
1843 wret
= fixup_low_keys(trans
, root
,
1844 path
, &disk_key
, 1);
1854 nritems
= nritems
- mid
;
1855 btrfs_set_header_nritems(right
, nritems
);
1856 data_copy_size
= btrfs_item_end_nr(l
, mid
) - leaf_data_end(root
, l
);
1858 copy_extent_buffer(right
, l
, btrfs_item_nr_offset(0),
1859 btrfs_item_nr_offset(mid
),
1860 nritems
* sizeof(struct btrfs_item
));
1862 copy_extent_buffer(right
, l
,
1863 btrfs_leaf_data(right
) + BTRFS_LEAF_DATA_SIZE(root
) -
1864 data_copy_size
, btrfs_leaf_data(l
) +
1865 leaf_data_end(root
, l
), data_copy_size
);
1867 rt_data_off
= BTRFS_LEAF_DATA_SIZE(root
) -
1868 btrfs_item_end_nr(l
, mid
);
1870 for (i
= 0; i
< nritems
; i
++) {
1871 struct btrfs_item
*item
= btrfs_item_nr(right
, i
);
1874 if (!right
->map_token
) {
1875 map_extent_buffer(right
, (unsigned long)item
,
1876 sizeof(struct btrfs_item
),
1877 &right
->map_token
, &right
->kaddr
,
1878 &right
->map_start
, &right
->map_len
,
1882 ioff
= btrfs_item_offset(right
, item
);
1883 btrfs_set_item_offset(right
, item
, ioff
+ rt_data_off
);
1886 if (right
->map_token
) {
1887 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1888 right
->map_token
= NULL
;
1891 btrfs_set_header_nritems(l
, mid
);
1893 btrfs_item_key(right
, &disk_key
, 0);
1894 wret
= insert_ptr(trans
, root
, path
, &disk_key
, right
->start
,
1895 path
->slots
[1] + 1, 1);
1899 btrfs_mark_buffer_dirty(right
);
1900 btrfs_mark_buffer_dirty(l
);
1901 BUG_ON(path
->slots
[0] != slot
);
1904 free_extent_buffer(path
->nodes
[0]);
1905 path
->nodes
[0] = right
;
1906 path
->slots
[0] -= mid
;
1907 path
->slots
[1] += 1;
1909 free_extent_buffer(right
);
1911 BUG_ON(path
->slots
[0] < 0);
1916 right
= btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
1919 return PTR_ERR(right
);
1921 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
1922 btrfs_set_header_bytenr(right
, right
->start
);
1923 btrfs_set_header_generation(right
, trans
->transid
);
1924 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
1925 btrfs_set_header_level(right
, 0);
1926 write_extent_buffer(right
, root
->fs_info
->fsid
,
1927 (unsigned long)btrfs_header_fsid(right
),
1930 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1931 btrfs_set_header_nritems(right
, 0);
1932 wret
= insert_ptr(trans
, root
, path
,
1933 &disk_key
, right
->start
,
1937 if (path
->slots
[1] == 0) {
1938 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1942 free_extent_buffer(path
->nodes
[0]);
1943 path
->nodes
[0] = right
;
1948 int btrfs_truncate_item(struct btrfs_trans_handle
*trans
,
1949 struct btrfs_root
*root
,
1950 struct btrfs_path
*path
,
1956 struct extent_buffer
*leaf
;
1957 struct btrfs_item
*item
;
1959 unsigned int data_end
;
1960 unsigned int old_data_start
;
1961 unsigned int old_size
;
1962 unsigned int size_diff
;
1965 slot_orig
= path
->slots
[0];
1966 leaf
= path
->nodes
[0];
1968 nritems
= btrfs_header_nritems(leaf
);
1969 data_end
= leaf_data_end(root
, leaf
);
1971 slot
= path
->slots
[0];
1972 old_data_start
= btrfs_item_offset_nr(leaf
, slot
);
1973 old_size
= btrfs_item_size_nr(leaf
, slot
);
1974 BUG_ON(old_size
<= new_size
);
1975 size_diff
= old_size
- new_size
;
1978 BUG_ON(slot
>= nritems
);
1981 * item0..itemN ... dataN.offset..dataN.size .. data0.size
1983 /* first correct the data pointers */
1984 for (i
= slot
; i
< nritems
; i
++) {
1986 item
= btrfs_item_nr(leaf
, i
);
1988 if (!leaf
->map_token
) {
1989 map_extent_buffer(leaf
, (unsigned long)item
,
1990 sizeof(struct btrfs_item
),
1991 &leaf
->map_token
, &leaf
->kaddr
,
1992 &leaf
->map_start
, &leaf
->map_len
,
1996 ioff
= btrfs_item_offset(leaf
, item
);
1997 btrfs_set_item_offset(leaf
, item
, ioff
+ size_diff
);
2000 if (leaf
->map_token
) {
2001 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2002 leaf
->map_token
= NULL
;
2005 /* shift the data */
2006 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2007 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2008 data_end
, old_data_start
+ new_size
- data_end
);
2010 item
= btrfs_item_nr(leaf
, slot
);
2011 btrfs_set_item_size(leaf
, item
, new_size
);
2012 btrfs_mark_buffer_dirty(leaf
);
2015 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2016 btrfs_print_leaf(root
, leaf
);
2022 int btrfs_extend_item(struct btrfs_trans_handle
*trans
,
2023 struct btrfs_root
*root
, struct btrfs_path
*path
,
2029 struct extent_buffer
*leaf
;
2030 struct btrfs_item
*item
;
2032 unsigned int data_end
;
2033 unsigned int old_data
;
2034 unsigned int old_size
;
2037 slot_orig
= path
->slots
[0];
2038 leaf
= path
->nodes
[0];
2040 nritems
= btrfs_header_nritems(leaf
);
2041 data_end
= leaf_data_end(root
, leaf
);
2043 if (btrfs_leaf_free_space(root
, leaf
) < data_size
) {
2044 btrfs_print_leaf(root
, leaf
);
2047 slot
= path
->slots
[0];
2048 old_data
= btrfs_item_end_nr(leaf
, slot
);
2051 BUG_ON(slot
>= nritems
);
2054 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2056 /* first correct the data pointers */
2057 for (i
= slot
; i
< nritems
; i
++) {
2059 item
= btrfs_item_nr(leaf
, i
);
2061 if (!leaf
->map_token
) {
2062 map_extent_buffer(leaf
, (unsigned long)item
,
2063 sizeof(struct btrfs_item
),
2064 &leaf
->map_token
, &leaf
->kaddr
,
2065 &leaf
->map_start
, &leaf
->map_len
,
2068 ioff
= btrfs_item_offset(leaf
, item
);
2069 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2072 if (leaf
->map_token
) {
2073 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2074 leaf
->map_token
= NULL
;
2077 /* shift the data */
2078 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2079 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2080 data_end
, old_data
- data_end
);
2082 data_end
= old_data
;
2083 old_size
= btrfs_item_size_nr(leaf
, slot
);
2084 item
= btrfs_item_nr(leaf
, slot
);
2085 btrfs_set_item_size(leaf
, item
, old_size
+ data_size
);
2086 btrfs_mark_buffer_dirty(leaf
);
2089 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2090 btrfs_print_leaf(root
, leaf
);
2097 * Given a key and some data, insert an item into the tree.
2098 * This does all the path init required, making room in the tree if needed.
2100 int btrfs_insert_empty_item(struct btrfs_trans_handle
*trans
,
2101 struct btrfs_root
*root
,
2102 struct btrfs_path
*path
,
2103 struct btrfs_key
*cpu_key
, u32 data_size
)
2105 struct extent_buffer
*leaf
;
2106 struct btrfs_item
*item
;
2111 unsigned int data_end
;
2112 struct btrfs_disk_key disk_key
;
2114 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
);
2116 /* create a root if there isn't one */
2120 ret
= btrfs_search_slot(trans
, root
, cpu_key
, path
, data_size
, 1);
2127 slot_orig
= path
->slots
[0];
2128 leaf
= path
->nodes
[0];
2130 nritems
= btrfs_header_nritems(leaf
);
2131 data_end
= leaf_data_end(root
, leaf
);
2133 if (btrfs_leaf_free_space(root
, leaf
) <
2134 sizeof(struct btrfs_item
) + data_size
) {
2138 slot
= path
->slots
[0];
2141 if (slot
!= nritems
) {
2143 unsigned int old_data
= btrfs_item_end_nr(leaf
, slot
);
2145 if (old_data
< data_end
) {
2146 btrfs_print_leaf(root
, leaf
);
2147 printk("slot %d old_data %d data_end %d\n",
2148 slot
, old_data
, data_end
);
2152 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2154 /* first correct the data pointers */
2155 WARN_ON(leaf
->map_token
);
2156 for (i
= slot
; i
< nritems
; i
++) {
2159 item
= btrfs_item_nr(leaf
, i
);
2160 if (!leaf
->map_token
) {
2161 map_extent_buffer(leaf
, (unsigned long)item
,
2162 sizeof(struct btrfs_item
),
2163 &leaf
->map_token
, &leaf
->kaddr
,
2164 &leaf
->map_start
, &leaf
->map_len
,
2168 ioff
= btrfs_item_offset(leaf
, item
);
2169 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2171 if (leaf
->map_token
) {
2172 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2173 leaf
->map_token
= NULL
;
2176 /* shift the items */
2177 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ 1),
2178 btrfs_item_nr_offset(slot
),
2179 (nritems
- slot
) * sizeof(struct btrfs_item
));
2181 /* shift the data */
2182 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2183 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2184 data_end
, old_data
- data_end
);
2185 data_end
= old_data
;
2188 /* setup the item for the new data */
2189 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2190 item
= btrfs_item_nr(leaf
, slot
);
2191 btrfs_set_item_offset(leaf
, item
, data_end
- data_size
);
2192 btrfs_set_item_size(leaf
, item
, data_size
);
2193 btrfs_set_header_nritems(leaf
, nritems
+ 1);
2194 btrfs_mark_buffer_dirty(leaf
);
2198 ret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2200 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2201 btrfs_print_leaf(root
, leaf
);
2209 * Given a key and some data, insert an item into the tree.
2210 * This does all the path init required, making room in the tree if needed.
2212 int btrfs_insert_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
2213 *root
, struct btrfs_key
*cpu_key
, void *data
, u32
2217 struct btrfs_path
*path
;
2218 struct extent_buffer
*leaf
;
2221 path
= btrfs_alloc_path();
2223 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
2225 leaf
= path
->nodes
[0];
2226 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2227 write_extent_buffer(leaf
, data
, ptr
, data_size
);
2228 btrfs_mark_buffer_dirty(leaf
);
2230 btrfs_free_path(path
);
2235 * delete the pointer from a given node.
2237 * If the delete empties a node, the node is removed from the tree,
2238 * continuing all the way the root if required. The root is converted into
2239 * a leaf if all the nodes are emptied.
2241 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2242 struct btrfs_path
*path
, int level
, int slot
)
2244 struct extent_buffer
*parent
= path
->nodes
[level
];
2249 nritems
= btrfs_header_nritems(parent
);
2250 if (slot
!= nritems
-1) {
2251 memmove_extent_buffer(parent
,
2252 btrfs_node_key_ptr_offset(slot
),
2253 btrfs_node_key_ptr_offset(slot
+ 1),
2254 sizeof(struct btrfs_key_ptr
) *
2255 (nritems
- slot
- 1));
2258 btrfs_set_header_nritems(parent
, nritems
);
2259 if (nritems
== 0 && parent
== root
->node
) {
2260 BUG_ON(btrfs_header_level(root
->node
) != 1);
2261 /* just turn the root into a leaf and break */
2262 btrfs_set_header_level(root
->node
, 0);
2263 } else if (slot
== 0) {
2264 struct btrfs_disk_key disk_key
;
2266 btrfs_node_key(parent
, &disk_key
, 0);
2267 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, level
+ 1);
2271 btrfs_mark_buffer_dirty(parent
);
2276 * delete the item at the leaf level in path. If that empties
2277 * the leaf, remove it from the tree
2279 int btrfs_del_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2280 struct btrfs_path
*path
)
2283 struct extent_buffer
*leaf
;
2284 struct btrfs_item
*item
;
2291 leaf
= path
->nodes
[0];
2292 slot
= path
->slots
[0];
2293 doff
= btrfs_item_offset_nr(leaf
, slot
);
2294 dsize
= btrfs_item_size_nr(leaf
, slot
);
2295 nritems
= btrfs_header_nritems(leaf
);
2297 if (slot
!= nritems
- 1) {
2299 int data_end
= leaf_data_end(root
, leaf
);
2301 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2303 btrfs_leaf_data(leaf
) + data_end
,
2306 for (i
= slot
+ 1; i
< nritems
; i
++) {
2309 item
= btrfs_item_nr(leaf
, i
);
2310 if (!leaf
->map_token
) {
2311 map_extent_buffer(leaf
, (unsigned long)item
,
2312 sizeof(struct btrfs_item
),
2313 &leaf
->map_token
, &leaf
->kaddr
,
2314 &leaf
->map_start
, &leaf
->map_len
,
2317 ioff
= btrfs_item_offset(leaf
, item
);
2318 btrfs_set_item_offset(leaf
, item
, ioff
+ dsize
);
2321 if (leaf
->map_token
) {
2322 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2323 leaf
->map_token
= NULL
;
2326 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
),
2327 btrfs_item_nr_offset(slot
+ 1),
2328 sizeof(struct btrfs_item
) *
2329 (nritems
- slot
- 1));
2331 btrfs_set_header_nritems(leaf
, nritems
- 1);
2334 /* delete the leaf if we've emptied it */
2336 if (leaf
== root
->node
) {
2337 btrfs_set_header_level(leaf
, 0);
2339 clean_tree_block(trans
, root
, leaf
);
2340 wait_on_tree_block_writeback(root
, leaf
);
2341 wret
= del_ptr(trans
, root
, path
, 1, path
->slots
[1]);
2344 wret
= btrfs_free_extent(trans
, root
,
2345 leaf
->start
, leaf
->len
, 1);
2350 int used
= leaf_space_used(leaf
, 0, nritems
);
2352 struct btrfs_disk_key disk_key
;
2354 btrfs_item_key(leaf
, &disk_key
, 0);
2355 wret
= fixup_low_keys(trans
, root
, path
,
2361 /* delete the leaf if it is mostly empty */
2362 if (used
< BTRFS_LEAF_DATA_SIZE(root
) / 3) {
2363 /* push_leaf_left fixes the path.
2364 * make sure the path still points to our leaf
2365 * for possible call to del_ptr below
2367 slot
= path
->slots
[1];
2368 extent_buffer_get(leaf
);
2370 wret
= push_leaf_left(trans
, root
, path
, 1);
2371 if (wret
< 0 && wret
!= -ENOSPC
)
2374 if (path
->nodes
[0] == leaf
&&
2375 btrfs_header_nritems(leaf
)) {
2376 wret
= push_leaf_right(trans
, root
, path
, 1);
2377 if (wret
< 0 && wret
!= -ENOSPC
)
2381 if (btrfs_header_nritems(leaf
) == 0) {
2382 u64 bytenr
= leaf
->start
;
2383 u32 blocksize
= leaf
->len
;
2385 clean_tree_block(trans
, root
, leaf
);
2386 wait_on_tree_block_writeback(root
, leaf
);
2388 wret
= del_ptr(trans
, root
, path
, 1, slot
);
2392 free_extent_buffer(leaf
);
2393 wret
= btrfs_free_extent(trans
, root
, bytenr
,
2398 btrfs_mark_buffer_dirty(leaf
);
2399 free_extent_buffer(leaf
);
2402 btrfs_mark_buffer_dirty(leaf
);
2409 * walk up the tree as far as required to find the next leaf.
2410 * returns 0 if it found something or 1 if there are no greater leaves.
2411 * returns < 0 on io errors.
2413 int btrfs_next_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2418 struct extent_buffer
*c
;
2419 struct extent_buffer
*next
= NULL
;
2421 while(level
< BTRFS_MAX_LEVEL
) {
2422 if (!path
->nodes
[level
])
2425 slot
= path
->slots
[level
] + 1;
2426 c
= path
->nodes
[level
];
2427 if (slot
>= btrfs_header_nritems(c
)) {
2432 bytenr
= btrfs_node_blockptr(c
, slot
);
2434 free_extent_buffer(next
);
2437 reada_for_search(root
, path
, level
, slot
);
2439 next
= read_tree_block(root
, bytenr
,
2440 btrfs_level_size(root
, level
-1));
2443 path
->slots
[level
] = slot
;
2446 c
= path
->nodes
[level
];
2447 free_extent_buffer(c
);
2448 path
->nodes
[level
] = next
;
2449 path
->slots
[level
] = 0;
2453 reada_for_search(root
, path
, level
, 0);
2454 next
= read_tree_block(root
, btrfs_node_blockptr(next
, 0),
2455 btrfs_level_size(root
, level
- 1));