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.
20 #include "transaction.h"
21 #include "print-tree.h"
23 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
24 *root
, struct btrfs_path
*path
, int level
);
25 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
26 *root
, struct btrfs_key
*ins_key
,
27 struct btrfs_path
*path
, int data_size
, int extend
);
28 static int push_node_left(struct btrfs_trans_handle
*trans
,
29 struct btrfs_root
*root
, struct extent_buffer
*dst
,
30 struct extent_buffer
*src
);
31 static int balance_node_right(struct btrfs_trans_handle
*trans
,
32 struct btrfs_root
*root
,
33 struct extent_buffer
*dst_buf
,
34 struct extent_buffer
*src_buf
);
35 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
36 struct btrfs_path
*path
, int level
, int slot
);
38 inline void btrfs_init_path(struct btrfs_path
*p
)
40 memset(p
, 0, sizeof(*p
));
43 struct btrfs_path
*btrfs_alloc_path(void)
45 struct btrfs_path
*path
;
46 path
= kmalloc(sizeof(struct btrfs_path
), GFP_NOFS
);
48 btrfs_init_path(path
);
54 void btrfs_free_path(struct btrfs_path
*p
)
56 btrfs_release_path(NULL
, p
);
60 void btrfs_release_path(struct btrfs_root
*root
, struct btrfs_path
*p
)
63 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++) {
66 free_extent_buffer(p
->nodes
[i
]);
68 memset(p
, 0, sizeof(*p
));
71 static void add_root_to_dirty_list(struct btrfs_root
*root
)
73 if (root
->track_dirty
&& list_empty(&root
->dirty_list
)) {
74 list_add(&root
->dirty_list
,
75 &root
->fs_info
->dirty_cowonly_roots
);
79 int btrfs_copy_root(struct btrfs_trans_handle
*trans
,
80 struct btrfs_root
*root
,
81 struct extent_buffer
*buf
,
82 struct extent_buffer
**cow_ret
, u64 new_root_objectid
)
84 struct extent_buffer
*cow
;
88 struct btrfs_key first_key
;
89 struct btrfs_root
*new_root
;
91 new_root
= kmalloc(sizeof(*new_root
), GFP_NOFS
);
95 memcpy(new_root
, root
, sizeof(*new_root
));
96 new_root
->root_key
.objectid
= new_root_objectid
;
98 WARN_ON(root
->ref_cows
&& trans
->transid
!=
99 root
->fs_info
->running_transaction
->transid
);
100 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
102 level
= btrfs_header_level(buf
);
103 nritems
= btrfs_header_nritems(buf
);
106 btrfs_item_key_to_cpu(buf
, &first_key
, 0);
108 btrfs_node_key_to_cpu(buf
, &first_key
, 0);
110 first_key
.objectid
= 0;
112 cow
= __btrfs_alloc_free_block(trans
, new_root
, buf
->len
,
114 trans
->transid
, first_key
.objectid
,
115 level
, buf
->start
, 0);
121 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
122 btrfs_set_header_bytenr(cow
, cow
->start
);
123 btrfs_set_header_generation(cow
, trans
->transid
);
124 btrfs_set_header_owner(cow
, new_root_objectid
);
125 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
127 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
128 ret
= btrfs_inc_ref(trans
, new_root
, buf
);
134 btrfs_mark_buffer_dirty(cow
);
139 int __btrfs_cow_block(struct btrfs_trans_handle
*trans
,
140 struct btrfs_root
*root
,
141 struct extent_buffer
*buf
,
142 struct extent_buffer
*parent
, int parent_slot
,
143 struct extent_buffer
**cow_ret
,
144 u64 search_start
, u64 empty_size
)
147 struct extent_buffer
*cow
;
150 int different_trans
= 0;
152 struct btrfs_key first_key
;
154 if (root
->ref_cows
) {
155 root_gen
= trans
->transid
;
160 WARN_ON(root
->ref_cows
&& trans
->transid
!=
161 root
->fs_info
->running_transaction
->transid
);
162 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
164 level
= btrfs_header_level(buf
);
165 nritems
= btrfs_header_nritems(buf
);
168 btrfs_item_key_to_cpu(buf
, &first_key
, 0);
170 btrfs_node_key_to_cpu(buf
, &first_key
, 0);
172 first_key
.objectid
= 0;
174 cow
= __btrfs_alloc_free_block(trans
, root
, buf
->len
,
175 root
->root_key
.objectid
,
176 root_gen
, first_key
.objectid
, level
,
177 search_start
, empty_size
);
181 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
182 btrfs_set_header_bytenr(cow
, cow
->start
);
183 btrfs_set_header_generation(cow
, trans
->transid
);
184 btrfs_set_header_owner(cow
, root
->root_key
.objectid
);
185 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
187 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
188 if (btrfs_header_generation(buf
) != trans
->transid
) {
190 ret
= btrfs_inc_ref(trans
, root
, buf
);
194 clean_tree_block(trans
, root
, buf
);
197 if (buf
== root
->node
) {
198 root_gen
= btrfs_header_generation(buf
);
200 extent_buffer_get(cow
);
201 if (buf
!= root
->commit_root
) {
202 btrfs_free_extent(trans
, root
, buf
->start
,
203 buf
->len
, root
->root_key
.objectid
,
206 free_extent_buffer(buf
);
207 add_root_to_dirty_list(root
);
209 root_gen
= btrfs_header_generation(parent
);
210 btrfs_set_node_blockptr(parent
, parent_slot
,
212 WARN_ON(trans
->transid
== 0);
213 btrfs_set_node_ptr_generation(parent
, parent_slot
,
215 btrfs_mark_buffer_dirty(parent
);
216 WARN_ON(btrfs_header_generation(parent
) != trans
->transid
);
217 btrfs_free_extent(trans
, root
, buf
->start
, buf
->len
,
218 btrfs_header_owner(parent
), root_gen
,
221 free_extent_buffer(buf
);
222 btrfs_mark_buffer_dirty(cow
);
227 int btrfs_cow_block(struct btrfs_trans_handle
*trans
,
228 struct btrfs_root
*root
, struct extent_buffer
*buf
,
229 struct extent_buffer
*parent
, int parent_slot
,
230 struct extent_buffer
**cow_ret
)
235 if (trans->transaction != root->fs_info->running_transaction) {
236 printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid,
237 root->fs_info->running_transaction->transid);
241 if (trans
->transid
!= root
->fs_info
->generation
) {
242 printk(KERN_CRIT
"trans %llu running %llu\n",
243 (unsigned long long)trans
->transid
,
244 (unsigned long long)root
->fs_info
->generation
);
247 if (btrfs_header_generation(buf
) == trans
->transid
&&
248 !btrfs_header_flag(buf
, BTRFS_HEADER_FLAG_WRITTEN
)) {
253 search_start
= buf
->start
& ~((u64
)(1024 * 1024 * 1024) - 1);
254 ret
= __btrfs_cow_block(trans
, root
, buf
, parent
,
255 parent_slot
, cow_ret
, search_start
, 0);
260 static int close_blocks(u64 blocknr, u64 other, u32 blocksize)
262 if (blocknr < other && other - (blocknr + blocksize) < 32768)
264 if (blocknr > other && blocknr - (other + blocksize) < 32768)
271 * compare two keys in a memcmp fashion
273 int btrfs_comp_keys(struct btrfs_disk_key
*disk
, struct btrfs_key
*k2
)
277 btrfs_disk_key_to_cpu(&k1
, disk
);
279 if (k1
.objectid
> k2
->objectid
)
281 if (k1
.objectid
< k2
->objectid
)
283 if (k1
.type
> k2
->type
)
285 if (k1
.type
< k2
->type
)
287 if (k1
.offset
> k2
->offset
)
289 if (k1
.offset
< k2
->offset
)
296 int btrfs_realloc_node(struct btrfs_trans_handle
*trans
,
297 struct btrfs_root
*root
, struct extent_buffer
*parent
,
298 int start_slot
, int cache_only
, u64
*last_ret
,
299 struct btrfs_key
*progress
)
301 struct extent_buffer
*cur
;
302 struct extent_buffer
*tmp
;
304 u64 search_start
= *last_ret
;
314 int progress_passed
= 0;
315 struct btrfs_disk_key disk_key
;
317 parent_level
= btrfs_header_level(parent
);
318 if (cache_only
&& parent_level
!= 1)
321 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
322 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
323 root
->fs_info
->running_transaction
->transid
);
326 if (trans
->transid
!= root
->fs_info
->generation
) {
327 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
328 root
->fs_info
->generation
);
332 parent_nritems
= btrfs_header_nritems(parent
);
333 blocksize
= btrfs_level_size(root
, parent_level
- 1);
334 end_slot
= parent_nritems
;
336 if (parent_nritems
== 1)
339 for (i
= start_slot
; i
< end_slot
; i
++) {
342 if (!parent
->map_token
) {
343 map_extent_buffer(parent
,
344 btrfs_node_key_ptr_offset(i
),
345 sizeof(struct btrfs_key_ptr
),
346 &parent
->map_token
, &parent
->kaddr
,
347 &parent
->map_start
, &parent
->map_len
,
350 btrfs_node_key(parent
, &disk_key
, i
);
351 if (!progress_passed
&& comp_keys(&disk_key
, progress
) < 0)
355 blocknr
= btrfs_node_blockptr(parent
, i
);
357 last_block
= blocknr
;
360 other
= btrfs_node_blockptr(parent
, i
- 1);
361 close
= close_blocks(blocknr
, other
, blocksize
);
363 if (close
&& i
< end_slot
- 2) {
364 other
= btrfs_node_blockptr(parent
, i
+ 1);
365 close
= close_blocks(blocknr
, other
, blocksize
);
368 last_block
= blocknr
;
371 if (parent
->map_token
) {
372 unmap_extent_buffer(parent
, parent
->map_token
,
374 parent
->map_token
= NULL
;
377 cur
= btrfs_find_tree_block(root
, blocknr
, blocksize
);
379 uptodate
= btrfs_buffer_uptodate(cur
);
382 if (!cur
|| !uptodate
) {
384 free_extent_buffer(cur
);
388 cur
= read_tree_block(root
, blocknr
,
390 } else if (!uptodate
) {
391 btrfs_read_buffer(cur
);
394 if (search_start
== 0)
395 search_start
= last_block
;
397 err
= __btrfs_cow_block(trans
, root
, cur
, parent
, i
,
400 (end_slot
- i
) * blocksize
));
402 free_extent_buffer(cur
);
405 search_start
= tmp
->start
;
406 last_block
= tmp
->start
;
407 *last_ret
= search_start
;
408 if (parent_level
== 1)
409 btrfs_clear_buffer_defrag(tmp
);
410 free_extent_buffer(tmp
);
412 if (parent
->map_token
) {
413 unmap_extent_buffer(parent
, parent
->map_token
,
415 parent
->map_token
= NULL
;
422 * The leaf data grows from end-to-front in the node.
423 * this returns the address of the start of the last item,
424 * which is the stop of the leaf data stack
426 static inline unsigned int leaf_data_end(struct btrfs_root
*root
,
427 struct extent_buffer
*leaf
)
429 u32 nr
= btrfs_header_nritems(leaf
);
431 return BTRFS_LEAF_DATA_SIZE(root
);
432 return btrfs_item_offset_nr(leaf
, nr
- 1);
435 static int check_node(struct btrfs_root
*root
, struct btrfs_path
*path
,
438 struct extent_buffer
*parent
= NULL
;
439 struct extent_buffer
*node
= path
->nodes
[level
];
440 struct btrfs_disk_key parent_key
;
441 struct btrfs_disk_key node_key
;
444 struct btrfs_key cpukey
;
445 u32 nritems
= btrfs_header_nritems(node
);
447 if (path
->nodes
[level
+ 1])
448 parent
= path
->nodes
[level
+ 1];
450 slot
= path
->slots
[level
];
451 BUG_ON(nritems
== 0);
453 parent_slot
= path
->slots
[level
+ 1];
454 btrfs_node_key(parent
, &parent_key
, parent_slot
);
455 btrfs_node_key(node
, &node_key
, 0);
456 BUG_ON(memcmp(&parent_key
, &node_key
,
457 sizeof(struct btrfs_disk_key
)));
458 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
459 btrfs_header_bytenr(node
));
461 BUG_ON(nritems
> BTRFS_NODEPTRS_PER_BLOCK(root
));
463 btrfs_node_key_to_cpu(node
, &cpukey
, slot
- 1);
464 btrfs_node_key(node
, &node_key
, slot
);
465 BUG_ON(btrfs_comp_keys(&node_key
, &cpukey
) <= 0);
467 if (slot
< nritems
- 1) {
468 btrfs_node_key_to_cpu(node
, &cpukey
, slot
+ 1);
469 btrfs_node_key(node
, &node_key
, slot
);
470 BUG_ON(btrfs_comp_keys(&node_key
, &cpukey
) >= 0);
475 static int check_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
,
478 struct extent_buffer
*leaf
= path
->nodes
[level
];
479 struct extent_buffer
*parent
= NULL
;
481 struct btrfs_key cpukey
;
482 struct btrfs_disk_key parent_key
;
483 struct btrfs_disk_key leaf_key
;
484 int slot
= path
->slots
[0];
486 u32 nritems
= btrfs_header_nritems(leaf
);
488 if (path
->nodes
[level
+ 1])
489 parent
= path
->nodes
[level
+ 1];
495 parent_slot
= path
->slots
[level
+ 1];
496 btrfs_node_key(parent
, &parent_key
, parent_slot
);
497 btrfs_item_key(leaf
, &leaf_key
, 0);
499 BUG_ON(memcmp(&parent_key
, &leaf_key
,
500 sizeof(struct btrfs_disk_key
)));
501 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
502 btrfs_header_bytenr(leaf
));
505 for (i
= 0; nritems
> 1 && i
< nritems
- 2; i
++) {
506 btrfs_item_key_to_cpu(leaf
, &cpukey
, i
+ 1);
507 btrfs_item_key(leaf
, &leaf_key
, i
);
508 if (comp_keys(&leaf_key
, &cpukey
) >= 0) {
509 btrfs_print_leaf(root
, leaf
);
510 printk("slot %d offset bad key\n", i
);
513 if (btrfs_item_offset_nr(leaf
, i
) !=
514 btrfs_item_end_nr(leaf
, i
+ 1)) {
515 btrfs_print_leaf(root
, leaf
);
516 printk("slot %d offset bad\n", i
);
520 if (btrfs_item_offset_nr(leaf
, i
) +
521 btrfs_item_size_nr(leaf
, i
) !=
522 BTRFS_LEAF_DATA_SIZE(root
)) {
523 btrfs_print_leaf(root
, leaf
);
524 printk("slot %d first offset bad\n", i
);
530 if (btrfs_item_size_nr(leaf
, nritems
- 1) > 4096) {
531 btrfs_print_leaf(root
, leaf
);
532 printk("slot %d bad size \n", nritems
- 1);
537 if (slot
!= 0 && slot
< nritems
- 1) {
538 btrfs_item_key(leaf
, &leaf_key
, slot
);
539 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
- 1);
540 if (btrfs_comp_keys(&leaf_key
, &cpukey
) <= 0) {
541 btrfs_print_leaf(root
, leaf
);
542 printk("slot %d offset bad key\n", slot
);
545 if (btrfs_item_offset_nr(leaf
, slot
- 1) !=
546 btrfs_item_end_nr(leaf
, slot
)) {
547 btrfs_print_leaf(root
, leaf
);
548 printk("slot %d offset bad\n", slot
);
552 if (slot
< nritems
- 1) {
553 btrfs_item_key(leaf
, &leaf_key
, slot
);
554 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
+ 1);
555 BUG_ON(btrfs_comp_keys(&leaf_key
, &cpukey
) >= 0);
556 if (btrfs_item_offset_nr(leaf
, slot
) !=
557 btrfs_item_end_nr(leaf
, slot
+ 1)) {
558 btrfs_print_leaf(root
, leaf
);
559 printk("slot %d offset bad\n", slot
);
563 BUG_ON(btrfs_item_offset_nr(leaf
, 0) +
564 btrfs_item_size_nr(leaf
, 0) != BTRFS_LEAF_DATA_SIZE(root
));
568 static int noinline
check_block(struct btrfs_root
*root
,
569 struct btrfs_path
*path
, int level
)
573 struct extent_buffer
*buf
= path
->nodes
[level
];
575 if (memcmp_extent_buffer(buf
, root
->fs_info
->fsid
,
576 (unsigned long)btrfs_header_fsid(buf
),
578 printk("warning bad block %Lu\n", buf
->start
);
583 return check_leaf(root
, path
, level
);
584 return check_node(root
, path
, level
);
588 * search for key in the extent_buffer. The items start at offset p,
589 * and they are item_size apart. There are 'max' items in p.
591 * the slot in the array is returned via slot, and it points to
592 * the place where you would insert key if it is not found in
595 * slot may point to max if the key is bigger than all of the keys
597 static int generic_bin_search(struct extent_buffer
*eb
, unsigned long p
,
598 int item_size
, struct btrfs_key
*key
,
605 unsigned long offset
;
606 struct btrfs_disk_key
*tmp
;
609 mid
= (low
+ high
) / 2;
610 offset
= p
+ mid
* item_size
;
612 tmp
= (struct btrfs_disk_key
*)(eb
->data
+ offset
);
613 ret
= btrfs_comp_keys(tmp
, key
);
629 * simple bin_search frontend that does the right thing for
632 static int bin_search(struct extent_buffer
*eb
, struct btrfs_key
*key
,
633 int level
, int *slot
)
636 return generic_bin_search(eb
,
637 offsetof(struct btrfs_leaf
, items
),
638 sizeof(struct btrfs_item
),
639 key
, btrfs_header_nritems(eb
),
642 return generic_bin_search(eb
,
643 offsetof(struct btrfs_node
, ptrs
),
644 sizeof(struct btrfs_key_ptr
),
645 key
, btrfs_header_nritems(eb
),
651 static struct extent_buffer
*read_node_slot(struct btrfs_root
*root
,
652 struct extent_buffer
*parent
, int slot
)
656 if (slot
>= btrfs_header_nritems(parent
))
658 return read_tree_block(root
, btrfs_node_blockptr(parent
, slot
),
659 btrfs_level_size(root
, btrfs_header_level(parent
) - 1));
662 static int balance_level(struct btrfs_trans_handle
*trans
,
663 struct btrfs_root
*root
,
664 struct btrfs_path
*path
, int level
)
666 struct extent_buffer
*right
= NULL
;
667 struct extent_buffer
*mid
;
668 struct extent_buffer
*left
= NULL
;
669 struct extent_buffer
*parent
= NULL
;
673 int orig_slot
= path
->slots
[level
];
674 int err_on_enospc
= 0;
680 mid
= path
->nodes
[level
];
681 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
683 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
685 if (level
< BTRFS_MAX_LEVEL
- 1)
686 parent
= path
->nodes
[level
+ 1];
687 pslot
= path
->slots
[level
+ 1];
690 * deal with the case where there is only one pointer in the root
691 * by promoting the node below to a root
694 struct extent_buffer
*child
;
696 if (btrfs_header_nritems(mid
) != 1)
699 /* promote the child to a root */
700 child
= read_node_slot(root
, mid
, 0);
702 ret
= btrfs_cow_block(trans
, root
, child
, mid
, 0, &child
);
706 add_root_to_dirty_list(root
);
707 path
->nodes
[level
] = NULL
;
708 clean_tree_block(trans
, root
, mid
);
709 wait_on_tree_block_writeback(root
, mid
);
710 /* once for the path */
711 free_extent_buffer(mid
);
712 ret
= btrfs_free_extent(trans
, root
, mid
->start
, mid
->len
,
713 root
->root_key
.objectid
,
714 btrfs_header_generation(mid
), 0, 0, 1);
715 /* once for the root ptr */
716 free_extent_buffer(mid
);
719 if (btrfs_header_nritems(mid
) >
720 BTRFS_NODEPTRS_PER_BLOCK(root
) / 4)
723 if (btrfs_header_nritems(mid
) < 2)
726 left
= read_node_slot(root
, parent
, pslot
- 1);
728 wret
= btrfs_cow_block(trans
, root
, left
,
729 parent
, pslot
- 1, &left
);
735 right
= read_node_slot(root
, parent
, pslot
+ 1);
737 wret
= btrfs_cow_block(trans
, root
, right
,
738 parent
, pslot
+ 1, &right
);
745 /* first, try to make some room in the middle buffer */
747 orig_slot
+= btrfs_header_nritems(left
);
748 wret
= push_node_left(trans
, root
, left
, mid
);
751 if (btrfs_header_nritems(mid
) < 2)
756 * then try to empty the right most buffer into the middle
759 wret
= push_node_left(trans
, root
, mid
, right
);
760 if (wret
< 0 && wret
!= -ENOSPC
)
762 if (btrfs_header_nritems(right
) == 0) {
763 u64 bytenr
= right
->start
;
764 u64 generation
= btrfs_header_generation(parent
);
765 u32 blocksize
= right
->len
;
767 clean_tree_block(trans
, root
, right
);
768 wait_on_tree_block_writeback(root
, right
);
769 free_extent_buffer(right
);
771 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
+
775 wret
= btrfs_free_extent(trans
, root
, bytenr
,
777 btrfs_header_owner(parent
),
778 generation
, 0, 0, 1);
782 struct btrfs_disk_key right_key
;
783 btrfs_node_key(right
, &right_key
, 0);
784 btrfs_set_node_key(parent
, &right_key
, pslot
+ 1);
785 btrfs_mark_buffer_dirty(parent
);
788 if (btrfs_header_nritems(mid
) == 1) {
790 * we're not allowed to leave a node with one item in the
791 * tree during a delete. A deletion from lower in the tree
792 * could try to delete the only pointer in this node.
793 * So, pull some keys from the left.
794 * There has to be a left pointer at this point because
795 * otherwise we would have pulled some pointers from the
799 wret
= balance_node_right(trans
, root
, mid
, left
);
806 if (btrfs_header_nritems(mid
) == 0) {
807 /* we've managed to empty the middle node, drop it */
808 u64 root_gen
= btrfs_header_generation(parent
);
809 u64 bytenr
= mid
->start
;
810 u32 blocksize
= mid
->len
;
811 clean_tree_block(trans
, root
, mid
);
812 wait_on_tree_block_writeback(root
, mid
);
813 free_extent_buffer(mid
);
815 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
);
818 wret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
,
819 btrfs_header_owner(parent
),
824 /* update the parent key to reflect our changes */
825 struct btrfs_disk_key mid_key
;
826 btrfs_node_key(mid
, &mid_key
, 0);
827 btrfs_set_node_key(parent
, &mid_key
, pslot
);
828 btrfs_mark_buffer_dirty(parent
);
831 /* update the path */
833 if (btrfs_header_nritems(left
) > orig_slot
) {
834 extent_buffer_get(left
);
835 path
->nodes
[level
] = left
;
836 path
->slots
[level
+ 1] -= 1;
837 path
->slots
[level
] = orig_slot
;
839 free_extent_buffer(mid
);
841 orig_slot
-= btrfs_header_nritems(left
);
842 path
->slots
[level
] = orig_slot
;
845 /* double check we haven't messed things up */
846 check_block(root
, path
, level
);
848 btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]))
852 free_extent_buffer(right
);
854 free_extent_buffer(left
);
858 /* returns zero if the push worked, non-zero otherwise */
859 static int noinline
push_nodes_for_insert(struct btrfs_trans_handle
*trans
,
860 struct btrfs_root
*root
,
861 struct btrfs_path
*path
, int level
)
863 struct extent_buffer
*right
= NULL
;
864 struct extent_buffer
*mid
;
865 struct extent_buffer
*left
= NULL
;
866 struct extent_buffer
*parent
= NULL
;
870 int orig_slot
= path
->slots
[level
];
876 mid
= path
->nodes
[level
];
877 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
878 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
880 if (level
< BTRFS_MAX_LEVEL
- 1)
881 parent
= path
->nodes
[level
+ 1];
882 pslot
= path
->slots
[level
+ 1];
887 left
= read_node_slot(root
, parent
, pslot
- 1);
889 /* first, try to make some room in the middle buffer */
892 left_nr
= btrfs_header_nritems(left
);
893 if (left_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
896 ret
= btrfs_cow_block(trans
, root
, left
, parent
,
901 wret
= push_node_left(trans
, root
,
908 struct btrfs_disk_key disk_key
;
909 orig_slot
+= left_nr
;
910 btrfs_node_key(mid
, &disk_key
, 0);
911 btrfs_set_node_key(parent
, &disk_key
, pslot
);
912 btrfs_mark_buffer_dirty(parent
);
913 if (btrfs_header_nritems(left
) > orig_slot
) {
914 path
->nodes
[level
] = left
;
915 path
->slots
[level
+ 1] -= 1;
916 path
->slots
[level
] = orig_slot
;
917 free_extent_buffer(mid
);
920 btrfs_header_nritems(left
);
921 path
->slots
[level
] = orig_slot
;
922 free_extent_buffer(left
);
926 free_extent_buffer(left
);
928 right
= read_node_slot(root
, parent
, pslot
+ 1);
931 * then try to empty the right most buffer into the middle
935 right_nr
= btrfs_header_nritems(right
);
936 if (right_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
939 ret
= btrfs_cow_block(trans
, root
, right
,
945 wret
= balance_node_right(trans
, root
,
952 struct btrfs_disk_key disk_key
;
954 btrfs_node_key(right
, &disk_key
, 0);
955 btrfs_set_node_key(parent
, &disk_key
, pslot
+ 1);
956 btrfs_mark_buffer_dirty(parent
);
958 if (btrfs_header_nritems(mid
) <= orig_slot
) {
959 path
->nodes
[level
] = right
;
960 path
->slots
[level
+ 1] += 1;
961 path
->slots
[level
] = orig_slot
-
962 btrfs_header_nritems(mid
);
963 free_extent_buffer(mid
);
965 free_extent_buffer(right
);
969 free_extent_buffer(right
);
975 * readahead one full node of leaves
977 static void reada_for_search(struct btrfs_root
*root
, struct btrfs_path
*path
,
978 int level
, int slot
, u64 objectid
)
980 struct extent_buffer
*node
;
981 struct btrfs_disk_key disk_key
;
987 int direction
= path
->reada
;
988 struct extent_buffer
*eb
;
996 if (!path
->nodes
[level
])
999 node
= path
->nodes
[level
];
1000 search
= btrfs_node_blockptr(node
, slot
);
1001 blocksize
= btrfs_level_size(root
, level
- 1);
1002 eb
= btrfs_find_tree_block(root
, search
, blocksize
);
1004 free_extent_buffer(eb
);
1008 highest_read
= search
;
1009 lowest_read
= search
;
1011 nritems
= btrfs_header_nritems(node
);
1014 if (direction
< 0) {
1018 } else if (direction
> 0) {
1023 if (path
->reada
< 0 && objectid
) {
1024 btrfs_node_key(node
, &disk_key
, nr
);
1025 if (btrfs_disk_key_objectid(&disk_key
) != objectid
)
1028 search
= btrfs_node_blockptr(node
, nr
);
1029 if ((search
>= lowest_read
&& search
<= highest_read
) ||
1030 (search
< lowest_read
&& lowest_read
- search
<= 32768) ||
1031 (search
> highest_read
&& search
- highest_read
<= 32768)) {
1032 readahead_tree_block(root
, search
, blocksize
);
1036 if (path
->reada
< 2 && (nread
> (256 * 1024) || nscan
> 32))
1038 if(nread
> (1024 * 1024) || nscan
> 128)
1041 if (search
< lowest_read
)
1042 lowest_read
= search
;
1043 if (search
> highest_read
)
1044 highest_read
= search
;
1049 * look for key in the tree. path is filled in with nodes along the way
1050 * if key is found, we return zero and you can find the item in the leaf
1051 * level of the path (level 0)
1053 * If the key isn't found, the path points to the slot where it should
1054 * be inserted, and 1 is returned. If there are other errors during the
1055 * search a negative error number is returned.
1057 * if ins_len > 0, nodes and leaves will be split as we walk down the
1058 * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
1061 int btrfs_search_slot(struct btrfs_trans_handle
*trans
, struct btrfs_root
1062 *root
, struct btrfs_key
*key
, struct btrfs_path
*p
, int
1065 struct extent_buffer
*b
;
1071 int should_reada
= p
->reada
;
1072 u8 lowest_level
= 0;
1074 lowest_level
= p
->lowest_level
;
1075 WARN_ON(lowest_level
&& ins_len
);
1076 WARN_ON(p
->nodes
[0] != NULL
);
1078 WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
1082 extent_buffer_get(b
);
1084 level
= btrfs_header_level(b
);
1087 wret
= btrfs_cow_block(trans
, root
, b
,
1088 p
->nodes
[level
+ 1],
1089 p
->slots
[level
+ 1],
1092 free_extent_buffer(b
);
1096 BUG_ON(!cow
&& ins_len
);
1097 if (level
!= btrfs_header_level(b
))
1099 level
= btrfs_header_level(b
);
1100 p
->nodes
[level
] = b
;
1101 ret
= check_block(root
, p
, level
);
1104 ret
= bin_search(b
, key
, level
, &slot
);
1106 if (ret
&& slot
> 0)
1108 p
->slots
[level
] = slot
;
1109 if (ins_len
> 0 && btrfs_header_nritems(b
) >=
1110 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
1111 int sret
= split_node(trans
, root
, p
, level
);
1115 b
= p
->nodes
[level
];
1116 slot
= p
->slots
[level
];
1117 } else if (ins_len
< 0) {
1118 int sret
= balance_level(trans
, root
, p
,
1122 b
= p
->nodes
[level
];
1124 btrfs_release_path(NULL
, p
);
1127 slot
= p
->slots
[level
];
1128 BUG_ON(btrfs_header_nritems(b
) == 1);
1130 /* this is only true while dropping a snapshot */
1131 if (level
== lowest_level
)
1133 bytenr
= btrfs_node_blockptr(b
, slot
);
1134 ptr_gen
= btrfs_node_ptr_generation(b
, slot
);
1136 reada_for_search(root
, p
, level
, slot
,
1138 b
= read_tree_block(root
, bytenr
,
1139 btrfs_level_size(root
, level
- 1));
1140 if (ptr_gen
!= btrfs_header_generation(b
)) {
1141 printk("block %llu bad gen wanted %llu "
1143 (unsigned long long)b
->start
,
1144 (unsigned long long)ptr_gen
,
1145 (unsigned long long)btrfs_header_generation(b
));
1148 p
->slots
[level
] = slot
;
1149 if (ins_len
> 0 && btrfs_leaf_free_space(root
, b
) <
1150 sizeof(struct btrfs_item
) + ins_len
) {
1151 int sret
= split_leaf(trans
, root
, key
,
1152 p
, ins_len
, ret
== 0);
1164 * adjust the pointers going up the tree, starting at level
1165 * making sure the right key of each node is points to 'key'.
1166 * This is used after shifting pointers to the left, so it stops
1167 * fixing up pointers when a given leaf/node is not in slot 0 of the
1170 * If this fails to write a tree block, it returns -1, but continues
1171 * fixing up the blocks in ram so the tree is consistent.
1173 static int fixup_low_keys(struct btrfs_trans_handle
*trans
,
1174 struct btrfs_root
*root
, struct btrfs_path
*path
,
1175 struct btrfs_disk_key
*key
, int level
)
1179 struct extent_buffer
*t
;
1181 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1182 int tslot
= path
->slots
[i
];
1183 if (!path
->nodes
[i
])
1186 btrfs_set_node_key(t
, key
, tslot
);
1187 btrfs_mark_buffer_dirty(path
->nodes
[i
]);
1195 * try to push data from one node into the next node left in the
1198 * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
1199 * error, and > 0 if there was no room in the left hand block.
1201 static int push_node_left(struct btrfs_trans_handle
*trans
,
1202 struct btrfs_root
*root
, struct extent_buffer
*dst
,
1203 struct extent_buffer
*src
)
1210 src_nritems
= btrfs_header_nritems(src
);
1211 dst_nritems
= btrfs_header_nritems(dst
);
1212 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1213 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1214 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1216 if (push_items
<= 0) {
1220 if (src_nritems
< push_items
)
1221 push_items
= src_nritems
;
1223 copy_extent_buffer(dst
, src
,
1224 btrfs_node_key_ptr_offset(dst_nritems
),
1225 btrfs_node_key_ptr_offset(0),
1226 push_items
* sizeof(struct btrfs_key_ptr
));
1228 if (push_items
< src_nritems
) {
1229 memmove_extent_buffer(src
, btrfs_node_key_ptr_offset(0),
1230 btrfs_node_key_ptr_offset(push_items
),
1231 (src_nritems
- push_items
) *
1232 sizeof(struct btrfs_key_ptr
));
1234 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1235 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1236 btrfs_mark_buffer_dirty(src
);
1237 btrfs_mark_buffer_dirty(dst
);
1242 * try to push data from one node into the next node right in the
1245 * returns 0 if some ptrs were pushed, < 0 if there was some horrible
1246 * error, and > 0 if there was no room in the right hand block.
1248 * this will only push up to 1/2 the contents of the left node over
1250 static int balance_node_right(struct btrfs_trans_handle
*trans
,
1251 struct btrfs_root
*root
,
1252 struct extent_buffer
*dst
,
1253 struct extent_buffer
*src
)
1261 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1262 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1264 src_nritems
= btrfs_header_nritems(src
);
1265 dst_nritems
= btrfs_header_nritems(dst
);
1266 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1267 if (push_items
<= 0)
1270 max_push
= src_nritems
/ 2 + 1;
1271 /* don't try to empty the node */
1272 if (max_push
>= src_nritems
)
1275 if (max_push
< push_items
)
1276 push_items
= max_push
;
1278 memmove_extent_buffer(dst
, btrfs_node_key_ptr_offset(push_items
),
1279 btrfs_node_key_ptr_offset(0),
1281 sizeof(struct btrfs_key_ptr
));
1283 copy_extent_buffer(dst
, src
,
1284 btrfs_node_key_ptr_offset(0),
1285 btrfs_node_key_ptr_offset(src_nritems
- push_items
),
1286 push_items
* sizeof(struct btrfs_key_ptr
));
1288 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1289 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1291 btrfs_mark_buffer_dirty(src
);
1292 btrfs_mark_buffer_dirty(dst
);
1297 * helper function to insert a new root level in the tree.
1298 * A new node is allocated, and a single item is inserted to
1299 * point to the existing root
1301 * returns zero on success or < 0 on failure.
1303 static int noinline
insert_new_root(struct btrfs_trans_handle
*trans
,
1304 struct btrfs_root
*root
,
1305 struct btrfs_path
*path
, int level
)
1309 struct extent_buffer
*lower
;
1310 struct extent_buffer
*c
;
1311 struct btrfs_disk_key lower_key
;
1313 BUG_ON(path
->nodes
[level
]);
1314 BUG_ON(path
->nodes
[level
-1] != root
->node
);
1317 root_gen
= trans
->transid
;
1321 lower
= path
->nodes
[level
-1];
1323 btrfs_item_key(lower
, &lower_key
, 0);
1325 btrfs_node_key(lower
, &lower_key
, 0);
1327 c
= __btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1328 root
->root_key
.objectid
,
1329 root_gen
, lower_key
.objectid
, level
,
1330 root
->node
->start
, 0);
1333 memset_extent_buffer(c
, 0, 0, root
->nodesize
);
1334 btrfs_set_header_nritems(c
, 1);
1335 btrfs_set_header_level(c
, level
);
1336 btrfs_set_header_bytenr(c
, c
->start
);
1337 btrfs_set_header_generation(c
, trans
->transid
);
1338 btrfs_set_header_owner(c
, root
->root_key
.objectid
);
1340 write_extent_buffer(c
, root
->fs_info
->fsid
,
1341 (unsigned long)btrfs_header_fsid(c
),
1344 write_extent_buffer(c
, root
->fs_info
->chunk_tree_uuid
,
1345 (unsigned long)btrfs_header_chunk_tree_uuid(c
),
1348 btrfs_set_node_key(c
, &lower_key
, 0);
1349 btrfs_set_node_blockptr(c
, 0, lower
->start
);
1350 lower_gen
= btrfs_header_generation(lower
);
1351 WARN_ON(lower_gen
== 0);
1353 btrfs_set_node_ptr_generation(c
, 0, lower_gen
);
1355 btrfs_mark_buffer_dirty(c
);
1357 /* the super has an extra ref to root->node */
1358 free_extent_buffer(root
->node
);
1360 add_root_to_dirty_list(root
);
1361 extent_buffer_get(c
);
1362 path
->nodes
[level
] = c
;
1363 path
->slots
[level
] = 0;
1365 if (root
->ref_cows
&& lower_gen
!= trans
->transid
) {
1366 struct btrfs_path
*back_path
= btrfs_alloc_path();
1368 ret
= btrfs_insert_extent_backref(trans
,
1369 root
->fs_info
->extent_root
,
1371 root
->root_key
.objectid
,
1372 trans
->transid
, 0, 0);
1374 btrfs_free_path(back_path
);
1380 * worker function to insert a single pointer in a node.
1381 * the node should have enough room for the pointer already
1383 * slot and level indicate where you want the key to go, and
1384 * blocknr is the block the key points to.
1386 * returns zero on success and < 0 on any error
1388 static int insert_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
1389 *root
, struct btrfs_path
*path
, struct btrfs_disk_key
1390 *key
, u64 bytenr
, int slot
, int level
)
1392 struct extent_buffer
*lower
;
1395 BUG_ON(!path
->nodes
[level
]);
1396 lower
= path
->nodes
[level
];
1397 nritems
= btrfs_header_nritems(lower
);
1400 if (nritems
== BTRFS_NODEPTRS_PER_BLOCK(root
))
1402 if (slot
!= nritems
) {
1403 memmove_extent_buffer(lower
,
1404 btrfs_node_key_ptr_offset(slot
+ 1),
1405 btrfs_node_key_ptr_offset(slot
),
1406 (nritems
- slot
) * sizeof(struct btrfs_key_ptr
));
1408 btrfs_set_node_key(lower
, key
, slot
);
1409 btrfs_set_node_blockptr(lower
, slot
, bytenr
);
1410 WARN_ON(trans
->transid
== 0);
1411 btrfs_set_node_ptr_generation(lower
, slot
, trans
->transid
);
1412 btrfs_set_header_nritems(lower
, nritems
+ 1);
1413 btrfs_mark_buffer_dirty(lower
);
1418 * split the node at the specified level in path in two.
1419 * The path is corrected to point to the appropriate node after the split
1421 * Before splitting this tries to make some room in the node by pushing
1422 * left and right, if either one works, it returns right away.
1424 * returns 0 on success and < 0 on failure
1426 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
1427 *root
, struct btrfs_path
*path
, int level
)
1430 struct extent_buffer
*c
;
1431 struct extent_buffer
*split
;
1432 struct btrfs_disk_key disk_key
;
1438 c
= path
->nodes
[level
];
1439 WARN_ON(btrfs_header_generation(c
) != trans
->transid
);
1440 if (c
== root
->node
) {
1441 /* trying to split the root, lets make a new one */
1442 ret
= insert_new_root(trans
, root
, path
, level
+ 1);
1446 ret
= push_nodes_for_insert(trans
, root
, path
, level
);
1447 c
= path
->nodes
[level
];
1448 if (!ret
&& btrfs_header_nritems(c
) <
1449 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1)
1455 c_nritems
= btrfs_header_nritems(c
);
1457 root_gen
= trans
->transid
;
1461 btrfs_node_key(c
, &disk_key
, 0);
1462 split
= __btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1463 root
->root_key
.objectid
,
1465 btrfs_disk_key_objectid(&disk_key
),
1466 level
, c
->start
, 0);
1468 return PTR_ERR(split
);
1470 btrfs_set_header_flags(split
, btrfs_header_flags(c
));
1471 btrfs_set_header_level(split
, btrfs_header_level(c
));
1472 btrfs_set_header_bytenr(split
, split
->start
);
1473 btrfs_set_header_generation(split
, trans
->transid
);
1474 btrfs_set_header_owner(split
, root
->root_key
.objectid
);
1475 btrfs_set_header_flags(split
, 0);
1476 write_extent_buffer(split
, root
->fs_info
->fsid
,
1477 (unsigned long)btrfs_header_fsid(split
),
1479 write_extent_buffer(split
, root
->fs_info
->chunk_tree_uuid
,
1480 (unsigned long)btrfs_header_chunk_tree_uuid(split
),
1483 mid
= (c_nritems
+ 1) / 2;
1485 copy_extent_buffer(split
, c
,
1486 btrfs_node_key_ptr_offset(0),
1487 btrfs_node_key_ptr_offset(mid
),
1488 (c_nritems
- mid
) * sizeof(struct btrfs_key_ptr
));
1489 btrfs_set_header_nritems(split
, c_nritems
- mid
);
1490 btrfs_set_header_nritems(c
, mid
);
1493 btrfs_mark_buffer_dirty(c
);
1494 btrfs_mark_buffer_dirty(split
);
1496 btrfs_node_key(split
, &disk_key
, 0);
1497 wret
= insert_ptr(trans
, root
, path
, &disk_key
, split
->start
,
1498 path
->slots
[level
+ 1] + 1,
1503 if (path
->slots
[level
] >= mid
) {
1504 path
->slots
[level
] -= mid
;
1505 free_extent_buffer(c
);
1506 path
->nodes
[level
] = split
;
1507 path
->slots
[level
+ 1] += 1;
1509 free_extent_buffer(split
);
1515 * how many bytes are required to store the items in a leaf. start
1516 * and nr indicate which items in the leaf to check. This totals up the
1517 * space used both by the item structs and the item data
1519 static int leaf_space_used(struct extent_buffer
*l
, int start
, int nr
)
1522 int nritems
= btrfs_header_nritems(l
);
1523 int end
= min(nritems
, start
+ nr
) - 1;
1527 data_len
= btrfs_item_end_nr(l
, start
);
1528 data_len
= data_len
- btrfs_item_offset_nr(l
, end
);
1529 data_len
+= sizeof(struct btrfs_item
) * nr
;
1530 WARN_ON(data_len
< 0);
1535 * The space between the end of the leaf items and
1536 * the start of the leaf data. IOW, how much room
1537 * the leaf has left for both items and data
1539 int btrfs_leaf_free_space(struct btrfs_root
*root
, struct extent_buffer
*leaf
)
1541 int nritems
= btrfs_header_nritems(leaf
);
1543 ret
= BTRFS_LEAF_DATA_SIZE(root
) - leaf_space_used(leaf
, 0, nritems
);
1545 printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
1546 ret
, (unsigned long) BTRFS_LEAF_DATA_SIZE(root
),
1547 leaf_space_used(leaf
, 0, nritems
), nritems
);
1553 * push some data in the path leaf to the right, trying to free up at
1554 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1556 * returns 1 if the push failed because the other node didn't have enough
1557 * room, 0 if everything worked out and < 0 if there were major errors.
1559 static int push_leaf_right(struct btrfs_trans_handle
*trans
, struct btrfs_root
1560 *root
, struct btrfs_path
*path
, int data_size
,
1563 struct extent_buffer
*left
= path
->nodes
[0];
1564 struct extent_buffer
*right
;
1565 struct extent_buffer
*upper
;
1566 struct btrfs_disk_key disk_key
;
1572 struct btrfs_item
*item
;
1580 slot
= path
->slots
[1];
1581 if (!path
->nodes
[1]) {
1584 upper
= path
->nodes
[1];
1585 if (slot
>= btrfs_header_nritems(upper
) - 1)
1588 right
= read_tree_block(root
, btrfs_node_blockptr(upper
, slot
+ 1),
1590 free_space
= btrfs_leaf_free_space(root
, right
);
1591 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1592 free_extent_buffer(right
);
1596 /* cow and double check */
1597 ret
= btrfs_cow_block(trans
, root
, right
, upper
,
1600 free_extent_buffer(right
);
1603 free_space
= btrfs_leaf_free_space(root
, right
);
1604 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1605 free_extent_buffer(right
);
1609 left_nritems
= btrfs_header_nritems(left
);
1610 if (left_nritems
== 0) {
1611 free_extent_buffer(right
);
1620 i
= left_nritems
- 1;
1622 item
= btrfs_item_nr(left
, i
);
1624 if (path
->slots
[0] == i
)
1625 push_space
+= data_size
+ sizeof(*item
);
1627 this_item_size
= btrfs_item_size(left
, item
);
1628 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1631 push_space
+= this_item_size
+ sizeof(*item
);
1637 if (push_items
== 0) {
1638 free_extent_buffer(right
);
1642 if (!empty
&& push_items
== left_nritems
)
1645 /* push left to right */
1646 right_nritems
= btrfs_header_nritems(right
);
1648 push_space
= btrfs_item_end_nr(left
, left_nritems
- push_items
);
1649 push_space
-= leaf_data_end(root
, left
);
1651 /* make room in the right data area */
1652 data_end
= leaf_data_end(root
, right
);
1653 memmove_extent_buffer(right
,
1654 btrfs_leaf_data(right
) + data_end
- push_space
,
1655 btrfs_leaf_data(right
) + data_end
,
1656 BTRFS_LEAF_DATA_SIZE(root
) - data_end
);
1658 /* copy from the left data area */
1659 copy_extent_buffer(right
, left
, btrfs_leaf_data(right
) +
1660 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1661 btrfs_leaf_data(left
) + leaf_data_end(root
, left
),
1664 memmove_extent_buffer(right
, btrfs_item_nr_offset(push_items
),
1665 btrfs_item_nr_offset(0),
1666 right_nritems
* sizeof(struct btrfs_item
));
1668 /* copy the items from left to right */
1669 copy_extent_buffer(right
, left
, btrfs_item_nr_offset(0),
1670 btrfs_item_nr_offset(left_nritems
- push_items
),
1671 push_items
* sizeof(struct btrfs_item
));
1673 /* update the item pointers */
1674 right_nritems
+= push_items
;
1675 btrfs_set_header_nritems(right
, right_nritems
);
1676 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1677 for (i
= 0; i
< right_nritems
; i
++) {
1678 item
= btrfs_item_nr(right
, i
);
1679 push_space
-= btrfs_item_size(right
, item
);
1680 btrfs_set_item_offset(right
, item
, push_space
);
1683 left_nritems
-= push_items
;
1684 btrfs_set_header_nritems(left
, left_nritems
);
1687 btrfs_mark_buffer_dirty(left
);
1688 btrfs_mark_buffer_dirty(right
);
1690 btrfs_item_key(right
, &disk_key
, 0);
1691 btrfs_set_node_key(upper
, &disk_key
, slot
+ 1);
1692 btrfs_mark_buffer_dirty(upper
);
1694 /* then fixup the leaf pointer in the path */
1695 if (path
->slots
[0] >= left_nritems
) {
1696 path
->slots
[0] -= left_nritems
;
1697 free_extent_buffer(path
->nodes
[0]);
1698 path
->nodes
[0] = right
;
1699 path
->slots
[1] += 1;
1701 free_extent_buffer(right
);
1706 * push some data in the path leaf to the left, trying to free up at
1707 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1709 static int push_leaf_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1710 *root
, struct btrfs_path
*path
, int data_size
,
1713 struct btrfs_disk_key disk_key
;
1714 struct extent_buffer
*right
= path
->nodes
[0];
1715 struct extent_buffer
*left
;
1721 struct btrfs_item
*item
;
1722 u32 old_left_nritems
;
1728 u32 old_left_item_size
;
1730 slot
= path
->slots
[1];
1733 if (!path
->nodes
[1])
1736 right_nritems
= btrfs_header_nritems(right
);
1737 if (right_nritems
== 0) {
1741 left
= read_tree_block(root
, btrfs_node_blockptr(path
->nodes
[1],
1742 slot
- 1), root
->leafsize
);
1743 free_space
= btrfs_leaf_free_space(root
, left
);
1744 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1745 free_extent_buffer(left
);
1749 /* cow and double check */
1750 ret
= btrfs_cow_block(trans
, root
, left
,
1751 path
->nodes
[1], slot
- 1, &left
);
1753 /* we hit -ENOSPC, but it isn't fatal here */
1754 free_extent_buffer(left
);
1758 free_space
= btrfs_leaf_free_space(root
, left
);
1759 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1760 free_extent_buffer(left
);
1767 nr
= right_nritems
- 1;
1769 for (i
= 0; i
< nr
; i
++) {
1770 item
= btrfs_item_nr(right
, i
);
1772 if (path
->slots
[0] == i
)
1773 push_space
+= data_size
+ sizeof(*item
);
1775 this_item_size
= btrfs_item_size(right
, item
);
1776 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1780 push_space
+= this_item_size
+ sizeof(*item
);
1783 if (push_items
== 0) {
1784 free_extent_buffer(left
);
1787 if (!empty
&& push_items
== btrfs_header_nritems(right
))
1790 /* push data from right to left */
1791 copy_extent_buffer(left
, right
,
1792 btrfs_item_nr_offset(btrfs_header_nritems(left
)),
1793 btrfs_item_nr_offset(0),
1794 push_items
* sizeof(struct btrfs_item
));
1796 push_space
= BTRFS_LEAF_DATA_SIZE(root
) -
1797 btrfs_item_offset_nr(right
, push_items
-1);
1799 copy_extent_buffer(left
, right
, btrfs_leaf_data(left
) +
1800 leaf_data_end(root
, left
) - push_space
,
1801 btrfs_leaf_data(right
) +
1802 btrfs_item_offset_nr(right
, push_items
- 1),
1804 old_left_nritems
= btrfs_header_nritems(left
);
1805 BUG_ON(old_left_nritems
< 0);
1807 old_left_item_size
= btrfs_item_offset_nr(left
, old_left_nritems
- 1);
1808 for (i
= old_left_nritems
; i
< old_left_nritems
+ push_items
; i
++) {
1811 item
= btrfs_item_nr(left
, i
);
1812 ioff
= btrfs_item_offset(left
, item
);
1813 btrfs_set_item_offset(left
, item
,
1814 ioff
- (BTRFS_LEAF_DATA_SIZE(root
) - old_left_item_size
));
1816 btrfs_set_header_nritems(left
, old_left_nritems
+ push_items
);
1818 /* fixup right node */
1819 if (push_items
> right_nritems
) {
1820 printk("push items %d nr %u\n", push_items
, right_nritems
);
1824 if (push_items
< right_nritems
) {
1825 push_space
= btrfs_item_offset_nr(right
, push_items
- 1) -
1826 leaf_data_end(root
, right
);
1827 memmove_extent_buffer(right
, btrfs_leaf_data(right
) +
1828 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1829 btrfs_leaf_data(right
) +
1830 leaf_data_end(root
, right
), push_space
);
1832 memmove_extent_buffer(right
, btrfs_item_nr_offset(0),
1833 btrfs_item_nr_offset(push_items
),
1834 (btrfs_header_nritems(right
) - push_items
) *
1835 sizeof(struct btrfs_item
));
1837 right_nritems
-= push_items
;
1838 btrfs_set_header_nritems(right
, right_nritems
);
1839 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1840 for (i
= 0; i
< right_nritems
; i
++) {
1841 item
= btrfs_item_nr(right
, i
);
1842 push_space
= push_space
- btrfs_item_size(right
, item
);
1843 btrfs_set_item_offset(right
, item
, push_space
);
1846 btrfs_mark_buffer_dirty(left
);
1848 btrfs_mark_buffer_dirty(right
);
1850 btrfs_item_key(right
, &disk_key
, 0);
1851 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1855 /* then fixup the leaf pointer in the path */
1856 if (path
->slots
[0] < push_items
) {
1857 path
->slots
[0] += old_left_nritems
;
1858 free_extent_buffer(path
->nodes
[0]);
1859 path
->nodes
[0] = left
;
1860 path
->slots
[1] -= 1;
1862 free_extent_buffer(left
);
1863 path
->slots
[0] -= push_items
;
1865 BUG_ON(path
->slots
[0] < 0);
1870 * split the path's leaf in two, making sure there is at least data_size
1871 * available for the resulting leaf level of the path.
1873 * returns 0 if all went well and < 0 on failure.
1875 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
1876 *root
, struct btrfs_key
*ins_key
,
1877 struct btrfs_path
*path
, int data_size
, int extend
)
1880 struct extent_buffer
*l
;
1884 struct extent_buffer
*right
;
1885 int space_needed
= data_size
+ sizeof(struct btrfs_item
);
1892 int num_doubles
= 0;
1893 struct btrfs_disk_key disk_key
;
1896 space_needed
= data_size
;
1899 root_gen
= trans
->transid
;
1903 /* first try to make some room by pushing left and right */
1904 if (ins_key
->type
!= BTRFS_DIR_ITEM_KEY
) {
1905 wret
= push_leaf_right(trans
, root
, path
, data_size
, 0);
1910 wret
= push_leaf_left(trans
, root
, path
, data_size
, 0);
1916 /* did the pushes work? */
1917 if (btrfs_leaf_free_space(root
, l
) >= space_needed
)
1921 if (!path
->nodes
[1]) {
1922 ret
= insert_new_root(trans
, root
, path
, 1);
1929 slot
= path
->slots
[0];
1930 nritems
= btrfs_header_nritems(l
);
1931 mid
= (nritems
+ 1)/ 2;
1933 btrfs_item_key(l
, &disk_key
, 0);
1935 right
= __btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
1936 root
->root_key
.objectid
,
1937 root_gen
, disk_key
.objectid
, 0,
1939 if (IS_ERR(right
)) {
1941 return PTR_ERR(right
);
1944 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
1945 btrfs_set_header_bytenr(right
, right
->start
);
1946 btrfs_set_header_generation(right
, trans
->transid
);
1947 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
1948 btrfs_set_header_level(right
, 0);
1949 write_extent_buffer(right
, root
->fs_info
->fsid
,
1950 (unsigned long)btrfs_header_fsid(right
),
1953 write_extent_buffer(right
, root
->fs_info
->chunk_tree_uuid
,
1954 (unsigned long)btrfs_header_chunk_tree_uuid(right
),
1958 leaf_space_used(l
, mid
, nritems
- mid
) + space_needed
>
1959 BTRFS_LEAF_DATA_SIZE(root
)) {
1960 if (slot
>= nritems
) {
1961 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1962 btrfs_set_header_nritems(right
, 0);
1963 wret
= insert_ptr(trans
, root
, path
,
1964 &disk_key
, right
->start
,
1965 path
->slots
[1] + 1, 1);
1968 free_extent_buffer(path
->nodes
[0]);
1969 path
->nodes
[0] = right
;
1971 path
->slots
[1] += 1;
1975 if (mid
!= nritems
&&
1976 leaf_space_used(l
, mid
, nritems
- mid
) +
1977 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
1982 if (leaf_space_used(l
, 0, mid
+ 1) + space_needed
>
1983 BTRFS_LEAF_DATA_SIZE(root
)) {
1984 if (!extend
&& slot
== 0) {
1985 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
1986 btrfs_set_header_nritems(right
, 0);
1987 wret
= insert_ptr(trans
, root
, path
,
1993 free_extent_buffer(path
->nodes
[0]);
1994 path
->nodes
[0] = right
;
1996 if (path
->slots
[1] == 0) {
1997 wret
= fixup_low_keys(trans
, root
,
1998 path
, &disk_key
, 1);
2003 } else if (extend
&& slot
== 0) {
2007 if (mid
!= nritems
&&
2008 leaf_space_used(l
, mid
, nritems
- mid
) +
2009 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2015 nritems
= nritems
- mid
;
2016 btrfs_set_header_nritems(right
, nritems
);
2017 data_copy_size
= btrfs_item_end_nr(l
, mid
) - leaf_data_end(root
, l
);
2019 copy_extent_buffer(right
, l
, btrfs_item_nr_offset(0),
2020 btrfs_item_nr_offset(mid
),
2021 nritems
* sizeof(struct btrfs_item
));
2023 copy_extent_buffer(right
, l
,
2024 btrfs_leaf_data(right
) + BTRFS_LEAF_DATA_SIZE(root
) -
2025 data_copy_size
, btrfs_leaf_data(l
) +
2026 leaf_data_end(root
, l
), data_copy_size
);
2028 rt_data_off
= BTRFS_LEAF_DATA_SIZE(root
) -
2029 btrfs_item_end_nr(l
, mid
);
2031 for (i
= 0; i
< nritems
; i
++) {
2032 struct btrfs_item
*item
= btrfs_item_nr(right
, i
);
2033 u32 ioff
= btrfs_item_offset(right
, item
);
2034 btrfs_set_item_offset(right
, item
, ioff
+ rt_data_off
);
2037 btrfs_set_header_nritems(l
, mid
);
2039 btrfs_item_key(right
, &disk_key
, 0);
2040 wret
= insert_ptr(trans
, root
, path
, &disk_key
, right
->start
,
2041 path
->slots
[1] + 1, 1);
2045 btrfs_mark_buffer_dirty(right
);
2046 btrfs_mark_buffer_dirty(l
);
2047 BUG_ON(path
->slots
[0] != slot
);
2050 free_extent_buffer(path
->nodes
[0]);
2051 path
->nodes
[0] = right
;
2052 path
->slots
[0] -= mid
;
2053 path
->slots
[1] += 1;
2055 free_extent_buffer(right
);
2057 BUG_ON(path
->slots
[0] < 0);
2060 BUG_ON(num_doubles
!= 0);
2067 int btrfs_truncate_item(struct btrfs_trans_handle
*trans
,
2068 struct btrfs_root
*root
,
2069 struct btrfs_path
*path
,
2070 u32 new_size
, int from_end
)
2075 struct extent_buffer
*leaf
;
2076 struct btrfs_item
*item
;
2078 unsigned int data_end
;
2079 unsigned int old_data_start
;
2080 unsigned int old_size
;
2081 unsigned int size_diff
;
2084 slot_orig
= path
->slots
[0];
2085 leaf
= path
->nodes
[0];
2086 slot
= path
->slots
[0];
2088 old_size
= btrfs_item_size_nr(leaf
, slot
);
2089 if (old_size
== new_size
)
2092 nritems
= btrfs_header_nritems(leaf
);
2093 data_end
= leaf_data_end(root
, leaf
);
2095 old_data_start
= btrfs_item_offset_nr(leaf
, slot
);
2097 size_diff
= old_size
- new_size
;
2100 BUG_ON(slot
>= nritems
);
2103 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2105 /* first correct the data pointers */
2106 for (i
= slot
; i
< nritems
; i
++) {
2108 item
= btrfs_item_nr(leaf
, i
);
2109 ioff
= btrfs_item_offset(leaf
, item
);
2110 btrfs_set_item_offset(leaf
, item
, ioff
+ size_diff
);
2113 /* shift the data */
2115 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2116 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2117 data_end
, old_data_start
+ new_size
- data_end
);
2119 struct btrfs_disk_key disk_key
;
2122 btrfs_item_key(leaf
, &disk_key
, slot
);
2124 if (btrfs_disk_key_type(&disk_key
) == BTRFS_EXTENT_DATA_KEY
) {
2126 struct btrfs_file_extent_item
*fi
;
2128 fi
= btrfs_item_ptr(leaf
, slot
,
2129 struct btrfs_file_extent_item
);
2130 fi
= (struct btrfs_file_extent_item
*)(
2131 (unsigned long)fi
- size_diff
);
2133 if (btrfs_file_extent_type(leaf
, fi
) ==
2134 BTRFS_FILE_EXTENT_INLINE
) {
2135 ptr
= btrfs_item_ptr_offset(leaf
, slot
);
2136 memmove_extent_buffer(leaf
, ptr
,
2138 offsetof(struct btrfs_file_extent_item
,
2143 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2144 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2145 data_end
, old_data_start
- data_end
);
2147 offset
= btrfs_disk_key_offset(&disk_key
);
2148 btrfs_set_disk_key_offset(&disk_key
, offset
+ size_diff
);
2149 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2151 fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2154 item
= btrfs_item_nr(leaf
, slot
);
2155 btrfs_set_item_size(leaf
, item
, new_size
);
2156 btrfs_mark_buffer_dirty(leaf
);
2159 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2160 btrfs_print_leaf(root
, leaf
);
2166 int btrfs_extend_item(struct btrfs_trans_handle
*trans
,
2167 struct btrfs_root
*root
, struct btrfs_path
*path
,
2173 struct extent_buffer
*leaf
;
2174 struct btrfs_item
*item
;
2176 unsigned int data_end
;
2177 unsigned int old_data
;
2178 unsigned int old_size
;
2181 slot_orig
= path
->slots
[0];
2182 leaf
= path
->nodes
[0];
2184 nritems
= btrfs_header_nritems(leaf
);
2185 data_end
= leaf_data_end(root
, leaf
);
2187 if (btrfs_leaf_free_space(root
, leaf
) < data_size
) {
2188 btrfs_print_leaf(root
, leaf
);
2191 slot
= path
->slots
[0];
2192 old_data
= btrfs_item_end_nr(leaf
, slot
);
2195 if (slot
>= nritems
) {
2196 btrfs_print_leaf(root
, leaf
);
2197 printk("slot %d too large, nritems %d\n", slot
, nritems
);
2202 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2204 /* first correct the data pointers */
2205 for (i
= slot
; i
< nritems
; i
++) {
2207 item
= btrfs_item_nr(leaf
, i
);
2208 ioff
= btrfs_item_offset(leaf
, item
);
2209 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2212 /* shift the data */
2213 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2214 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2215 data_end
, old_data
- data_end
);
2217 data_end
= old_data
;
2218 old_size
= btrfs_item_size_nr(leaf
, slot
);
2219 item
= btrfs_item_nr(leaf
, slot
);
2220 btrfs_set_item_size(leaf
, item
, old_size
+ data_size
);
2221 btrfs_mark_buffer_dirty(leaf
);
2224 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2225 btrfs_print_leaf(root
, leaf
);
2232 * Given a key and some data, insert an item into the tree.
2233 * This does all the path init required, making room in the tree if needed.
2235 int btrfs_insert_empty_items(struct btrfs_trans_handle
*trans
,
2236 struct btrfs_root
*root
,
2237 struct btrfs_path
*path
,
2238 struct btrfs_key
*cpu_key
, u32
*data_size
,
2241 struct extent_buffer
*leaf
;
2242 struct btrfs_item
*item
;
2250 unsigned int data_end
;
2251 struct btrfs_disk_key disk_key
;
2253 for (i
= 0; i
< nr
; i
++) {
2254 total_data
+= data_size
[i
];
2257 /* create a root if there isn't one */
2261 total_size
= total_data
+ (nr
- 1) * sizeof(struct btrfs_item
);
2262 ret
= btrfs_search_slot(trans
, root
, cpu_key
, path
, total_size
, 1);
2269 slot_orig
= path
->slots
[0];
2270 leaf
= path
->nodes
[0];
2272 nritems
= btrfs_header_nritems(leaf
);
2273 data_end
= leaf_data_end(root
, leaf
);
2275 if (btrfs_leaf_free_space(root
, leaf
) <
2276 sizeof(struct btrfs_item
) + total_size
) {
2277 btrfs_print_leaf(root
, leaf
);
2278 printk("not enough freespace need %u have %d\n",
2279 total_size
, btrfs_leaf_free_space(root
, leaf
));
2283 slot
= path
->slots
[0];
2286 if (slot
!= nritems
) {
2288 unsigned int old_data
= btrfs_item_end_nr(leaf
, slot
);
2290 if (old_data
< data_end
) {
2291 btrfs_print_leaf(root
, leaf
);
2292 printk("slot %d old_data %d data_end %d\n",
2293 slot
, old_data
, data_end
);
2297 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2299 /* first correct the data pointers */
2300 for (i
= slot
; i
< nritems
; i
++) {
2303 item
= btrfs_item_nr(leaf
, i
);
2304 ioff
= btrfs_item_offset(leaf
, item
);
2305 btrfs_set_item_offset(leaf
, item
, ioff
- total_data
);
2308 /* shift the items */
2309 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ nr
),
2310 btrfs_item_nr_offset(slot
),
2311 (nritems
- slot
) * sizeof(struct btrfs_item
));
2313 /* shift the data */
2314 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2315 data_end
- total_data
, btrfs_leaf_data(leaf
) +
2316 data_end
, old_data
- data_end
);
2317 data_end
= old_data
;
2320 /* setup the item for the new data */
2321 for (i
= 0; i
< nr
; i
++) {
2322 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
+ i
);
2323 btrfs_set_item_key(leaf
, &disk_key
, slot
+ i
);
2324 item
= btrfs_item_nr(leaf
, slot
+ i
);
2325 btrfs_set_item_offset(leaf
, item
, data_end
- data_size
[i
]);
2326 data_end
-= data_size
[i
];
2327 btrfs_set_item_size(leaf
, item
, data_size
[i
]);
2329 btrfs_set_header_nritems(leaf
, nritems
+ nr
);
2330 btrfs_mark_buffer_dirty(leaf
);
2334 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
);
2335 ret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2338 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2339 btrfs_print_leaf(root
, leaf
);
2348 * Given a key and some data, insert an item into the tree.
2349 * This does all the path init required, making room in the tree if needed.
2351 int btrfs_insert_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
2352 *root
, struct btrfs_key
*cpu_key
, void *data
, u32
2356 struct btrfs_path
*path
;
2357 struct extent_buffer
*leaf
;
2360 path
= btrfs_alloc_path();
2362 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
2364 leaf
= path
->nodes
[0];
2365 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2366 write_extent_buffer(leaf
, data
, ptr
, data_size
);
2367 btrfs_mark_buffer_dirty(leaf
);
2369 btrfs_free_path(path
);
2374 * delete the pointer from a given node.
2376 * If the delete empties a node, the node is removed from the tree,
2377 * continuing all the way the root if required. The root is converted into
2378 * a leaf if all the nodes are emptied.
2380 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2381 struct btrfs_path
*path
, int level
, int slot
)
2383 struct extent_buffer
*parent
= path
->nodes
[level
];
2388 nritems
= btrfs_header_nritems(parent
);
2389 if (slot
!= nritems
-1) {
2390 memmove_extent_buffer(parent
,
2391 btrfs_node_key_ptr_offset(slot
),
2392 btrfs_node_key_ptr_offset(slot
+ 1),
2393 sizeof(struct btrfs_key_ptr
) *
2394 (nritems
- slot
- 1));
2397 btrfs_set_header_nritems(parent
, nritems
);
2398 if (nritems
== 0 && parent
== root
->node
) {
2399 BUG_ON(btrfs_header_level(root
->node
) != 1);
2400 /* just turn the root into a leaf and break */
2401 btrfs_set_header_level(root
->node
, 0);
2402 } else if (slot
== 0) {
2403 struct btrfs_disk_key disk_key
;
2405 btrfs_node_key(parent
, &disk_key
, 0);
2406 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, level
+ 1);
2410 btrfs_mark_buffer_dirty(parent
);
2415 * delete the item at the leaf level in path. If that empties
2416 * the leaf, remove it from the tree
2418 int btrfs_del_items(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2419 struct btrfs_path
*path
, int slot
, int nr
)
2421 struct extent_buffer
*leaf
;
2422 struct btrfs_item
*item
;
2430 leaf
= path
->nodes
[0];
2431 last_off
= btrfs_item_offset_nr(leaf
, slot
+ nr
- 1);
2433 for (i
= 0; i
< nr
; i
++)
2434 dsize
+= btrfs_item_size_nr(leaf
, slot
+ i
);
2436 nritems
= btrfs_header_nritems(leaf
);
2438 if (slot
+ nr
!= nritems
) {
2440 int data_end
= leaf_data_end(root
, leaf
);
2442 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2444 btrfs_leaf_data(leaf
) + data_end
,
2445 last_off
- data_end
);
2447 for (i
= slot
+ nr
; i
< nritems
; i
++) {
2450 item
= btrfs_item_nr(leaf
, i
);
2451 ioff
= btrfs_item_offset(leaf
, item
);
2452 btrfs_set_item_offset(leaf
, item
, ioff
+ dsize
);
2455 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
),
2456 btrfs_item_nr_offset(slot
+ nr
),
2457 sizeof(struct btrfs_item
) *
2458 (nritems
- slot
- nr
));
2460 btrfs_set_header_nritems(leaf
, nritems
- nr
);
2463 /* delete the leaf if we've emptied it */
2465 if (leaf
== root
->node
) {
2466 btrfs_set_header_level(leaf
, 0);
2468 u64 root_gen
= btrfs_header_generation(path
->nodes
[1]);
2469 clean_tree_block(trans
, root
, leaf
);
2470 wait_on_tree_block_writeback(root
, leaf
);
2471 wret
= del_ptr(trans
, root
, path
, 1, path
->slots
[1]);
2474 wret
= btrfs_free_extent(trans
, root
,
2475 leaf
->start
, leaf
->len
,
2476 btrfs_header_owner(path
->nodes
[1]),
2482 int used
= leaf_space_used(leaf
, 0, nritems
);
2484 struct btrfs_disk_key disk_key
;
2486 btrfs_item_key(leaf
, &disk_key
, 0);
2487 wret
= fixup_low_keys(trans
, root
, path
,
2493 /* delete the leaf if it is mostly empty */
2494 if (used
< BTRFS_LEAF_DATA_SIZE(root
) / 4) {
2495 /* push_leaf_left fixes the path.
2496 * make sure the path still points to our leaf
2497 * for possible call to del_ptr below
2499 slot
= path
->slots
[1];
2500 extent_buffer_get(leaf
);
2502 wret
= push_leaf_left(trans
, root
, path
, 1, 1);
2503 if (wret
< 0 && wret
!= -ENOSPC
)
2506 if (path
->nodes
[0] == leaf
&&
2507 btrfs_header_nritems(leaf
)) {
2508 wret
= push_leaf_right(trans
, root
, path
, 1, 1);
2509 if (wret
< 0 && wret
!= -ENOSPC
)
2513 if (btrfs_header_nritems(leaf
) == 0) {
2515 u64 bytenr
= leaf
->start
;
2516 u32 blocksize
= leaf
->len
;
2518 root_gen
= btrfs_header_generation(
2521 clean_tree_block(trans
, root
, leaf
);
2522 wait_on_tree_block_writeback(root
, leaf
);
2524 wret
= del_ptr(trans
, root
, path
, 1, slot
);
2528 free_extent_buffer(leaf
);
2529 wret
= btrfs_free_extent(trans
, root
, bytenr
,
2531 btrfs_header_owner(path
->nodes
[1]),
2536 btrfs_mark_buffer_dirty(leaf
);
2537 free_extent_buffer(leaf
);
2540 btrfs_mark_buffer_dirty(leaf
);
2547 * walk up the tree as far as required to find the previous leaf.
2548 * returns 0 if it found something or 1 if there are no lesser leaves.
2549 * returns < 0 on io errors.
2551 int btrfs_prev_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2556 struct extent_buffer
*c
;
2557 struct extent_buffer
*next
= NULL
;
2559 while(level
< BTRFS_MAX_LEVEL
) {
2560 if (!path
->nodes
[level
])
2563 slot
= path
->slots
[level
];
2564 c
= path
->nodes
[level
];
2567 if (level
== BTRFS_MAX_LEVEL
)
2573 bytenr
= btrfs_node_blockptr(c
, slot
);
2575 free_extent_buffer(next
);
2577 next
= read_tree_block(root
, bytenr
,
2578 btrfs_level_size(root
, level
- 1));
2581 path
->slots
[level
] = slot
;
2584 c
= path
->nodes
[level
];
2585 free_extent_buffer(c
);
2586 slot
= btrfs_header_nritems(next
);
2589 path
->nodes
[level
] = next
;
2590 path
->slots
[level
] = slot
;
2593 next
= read_tree_block(root
, btrfs_node_blockptr(next
, slot
),
2594 btrfs_level_size(root
, level
- 1));
2600 * walk up the tree as far as required to find the next leaf.
2601 * returns 0 if it found something or 1 if there are no greater leaves.
2602 * returns < 0 on io errors.
2604 int btrfs_next_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2609 struct extent_buffer
*c
;
2610 struct extent_buffer
*next
= NULL
;
2612 while(level
< BTRFS_MAX_LEVEL
) {
2613 if (!path
->nodes
[level
])
2616 slot
= path
->slots
[level
] + 1;
2617 c
= path
->nodes
[level
];
2618 if (slot
>= btrfs_header_nritems(c
)) {
2620 if (level
== BTRFS_MAX_LEVEL
)
2625 bytenr
= btrfs_node_blockptr(c
, slot
);
2627 free_extent_buffer(next
);
2630 reada_for_search(root
, path
, level
, slot
, 0);
2632 next
= read_tree_block(root
, bytenr
,
2633 btrfs_level_size(root
, level
-1));
2636 path
->slots
[level
] = slot
;
2639 c
= path
->nodes
[level
];
2640 free_extent_buffer(c
);
2641 path
->nodes
[level
] = next
;
2642 path
->slots
[level
] = 0;
2646 reada_for_search(root
, path
, level
, 0, 0);
2647 next
= read_tree_block(root
, btrfs_node_blockptr(next
, 0),
2648 btrfs_level_size(root
, level
- 1));
2653 int btrfs_previous_item(struct btrfs_root
*root
,
2654 struct btrfs_path
*path
, u64 min_objectid
,
2657 struct btrfs_key found_key
;
2658 struct extent_buffer
*leaf
;
2662 if (path
->slots
[0] == 0) {
2663 ret
= btrfs_prev_leaf(root
, path
);
2669 leaf
= path
->nodes
[0];
2670 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
2671 if (found_key
.type
== type
)