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
, int empty
);
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
;
87 struct btrfs_root
*new_root
;
89 new_root
= kmalloc(sizeof(*new_root
), GFP_NOFS
);
93 memcpy(new_root
, root
, sizeof(*new_root
));
94 new_root
->root_key
.objectid
= new_root_objectid
;
96 WARN_ON(root
->ref_cows
&& trans
->transid
!=
97 root
->fs_info
->running_transaction
->transid
);
98 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
100 level
= btrfs_header_level(buf
);
101 cow
= btrfs_alloc_free_block(trans
, new_root
, buf
->len
, 0,
102 new_root_objectid
, trans
->transid
,
103 level
, buf
->start
, 0);
109 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
110 btrfs_set_header_bytenr(cow
, cow
->start
);
111 btrfs_set_header_generation(cow
, trans
->transid
);
112 btrfs_set_header_owner(cow
, new_root_objectid
);
113 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
115 write_extent_buffer(cow
, root
->fs_info
->fsid
,
116 (unsigned long)btrfs_header_fsid(cow
),
119 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
120 ret
= btrfs_inc_ref(trans
, new_root
, buf
, cow
, NULL
);
126 btrfs_mark_buffer_dirty(cow
);
131 int __btrfs_cow_block(struct btrfs_trans_handle
*trans
,
132 struct btrfs_root
*root
,
133 struct extent_buffer
*buf
,
134 struct extent_buffer
*parent
, int parent_slot
,
135 struct extent_buffer
**cow_ret
,
136 u64 search_start
, u64 empty_size
)
139 struct extent_buffer
*cow
;
142 int different_trans
= 0;
145 WARN_ON(root
->ref_cows
&& trans
->transid
!=
146 root
->fs_info
->running_transaction
->transid
);
147 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
150 parent_start
= parent
->start
;
154 level
= btrfs_header_level(buf
);
155 nritems
= btrfs_header_nritems(buf
);
156 cow
= btrfs_alloc_free_block(trans
, root
, buf
->len
, parent_start
,
157 root
->root_key
.objectid
, trans
->transid
,
158 level
, search_start
, empty_size
);
162 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
163 btrfs_set_header_bytenr(cow
, cow
->start
);
164 btrfs_set_header_generation(cow
, trans
->transid
);
165 btrfs_set_header_owner(cow
, root
->root_key
.objectid
);
166 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
168 write_extent_buffer(cow
, root
->fs_info
->fsid
,
169 (unsigned long)btrfs_header_fsid(cow
),
172 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
173 if (btrfs_header_generation(buf
) != trans
->transid
) {
175 ret
= btrfs_inc_ref(trans
, root
, buf
, cow
, NULL
);
179 ret
= btrfs_update_ref(trans
, root
, buf
, cow
, 0, nritems
);
182 clean_tree_block(trans
, root
, buf
);
185 if (buf
== root
->node
) {
187 extent_buffer_get(cow
);
188 if (buf
!= root
->commit_root
) {
189 btrfs_free_extent(trans
, root
, buf
->start
,
190 buf
->len
, buf
->start
,
191 root
->root_key
.objectid
,
192 btrfs_header_generation(buf
),
195 free_extent_buffer(buf
);
196 add_root_to_dirty_list(root
);
198 btrfs_set_node_blockptr(parent
, parent_slot
,
200 WARN_ON(trans
->transid
== 0);
201 btrfs_set_node_ptr_generation(parent
, parent_slot
,
203 btrfs_mark_buffer_dirty(parent
);
204 WARN_ON(btrfs_header_generation(parent
) != trans
->transid
);
205 btrfs_free_extent(trans
, root
, buf
->start
, buf
->len
,
206 parent_start
, btrfs_header_owner(parent
),
207 btrfs_header_generation(parent
), level
, 1);
209 free_extent_buffer(buf
);
210 btrfs_mark_buffer_dirty(cow
);
215 int btrfs_cow_block(struct btrfs_trans_handle
*trans
,
216 struct btrfs_root
*root
, struct extent_buffer
*buf
,
217 struct extent_buffer
*parent
, int parent_slot
,
218 struct extent_buffer
**cow_ret
)
223 if (trans->transaction != root->fs_info->running_transaction) {
224 printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid,
225 root->fs_info->running_transaction->transid);
229 if (trans
->transid
!= root
->fs_info
->generation
) {
230 printk(KERN_CRIT
"trans %llu running %llu\n",
231 (unsigned long long)trans
->transid
,
232 (unsigned long long)root
->fs_info
->generation
);
235 if (btrfs_header_generation(buf
) == trans
->transid
&&
236 !btrfs_header_flag(buf
, BTRFS_HEADER_FLAG_WRITTEN
)) {
241 search_start
= buf
->start
& ~((u64
)(1024 * 1024 * 1024) - 1);
242 ret
= __btrfs_cow_block(trans
, root
, buf
, parent
,
243 parent_slot
, cow_ret
, search_start
, 0);
248 static int close_blocks(u64 blocknr, u64 other, u32 blocksize)
250 if (blocknr < other && other - (blocknr + blocksize) < 32768)
252 if (blocknr > other && blocknr - (other + blocksize) < 32768)
259 * compare two keys in a memcmp fashion
261 int btrfs_comp_keys(struct btrfs_disk_key
*disk
, struct btrfs_key
*k2
)
265 btrfs_disk_key_to_cpu(&k1
, disk
);
267 if (k1
.objectid
> k2
->objectid
)
269 if (k1
.objectid
< k2
->objectid
)
271 if (k1
.type
> k2
->type
)
273 if (k1
.type
< k2
->type
)
275 if (k1
.offset
> k2
->offset
)
277 if (k1
.offset
< k2
->offset
)
284 int btrfs_realloc_node(struct btrfs_trans_handle
*trans
,
285 struct btrfs_root
*root
, struct extent_buffer
*parent
,
286 int start_slot
, int cache_only
, u64
*last_ret
,
287 struct btrfs_key
*progress
)
289 struct extent_buffer
*cur
;
290 struct extent_buffer
*tmp
;
293 u64 search_start
= *last_ret
;
303 int progress_passed
= 0;
304 struct btrfs_disk_key disk_key
;
306 parent_level
= btrfs_header_level(parent
);
307 if (cache_only
&& parent_level
!= 1)
310 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
311 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
312 root
->fs_info
->running_transaction
->transid
);
315 if (trans
->transid
!= root
->fs_info
->generation
) {
316 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
317 root
->fs_info
->generation
);
321 parent_nritems
= btrfs_header_nritems(parent
);
322 blocksize
= btrfs_level_size(root
, parent_level
- 1);
323 end_slot
= parent_nritems
;
325 if (parent_nritems
== 1)
328 for (i
= start_slot
; i
< end_slot
; i
++) {
331 if (!parent
->map_token
) {
332 map_extent_buffer(parent
,
333 btrfs_node_key_ptr_offset(i
),
334 sizeof(struct btrfs_key_ptr
),
335 &parent
->map_token
, &parent
->kaddr
,
336 &parent
->map_start
, &parent
->map_len
,
339 btrfs_node_key(parent
, &disk_key
, i
);
340 if (!progress_passed
&& comp_keys(&disk_key
, progress
) < 0)
344 blocknr
= btrfs_node_blockptr(parent
, i
);
345 gen
= btrfs_node_ptr_generation(parent
, i
);
347 last_block
= blocknr
;
350 other
= btrfs_node_blockptr(parent
, i
- 1);
351 close
= close_blocks(blocknr
, other
, blocksize
);
353 if (close
&& i
< end_slot
- 2) {
354 other
= btrfs_node_blockptr(parent
, i
+ 1);
355 close
= close_blocks(blocknr
, other
, blocksize
);
358 last_block
= blocknr
;
361 if (parent
->map_token
) {
362 unmap_extent_buffer(parent
, parent
->map_token
,
364 parent
->map_token
= NULL
;
367 cur
= btrfs_find_tree_block(root
, blocknr
, blocksize
);
369 uptodate
= btrfs_buffer_uptodate(cur
, gen
);
372 if (!cur
|| !uptodate
) {
374 free_extent_buffer(cur
);
378 cur
= read_tree_block(root
, blocknr
,
380 } else if (!uptodate
) {
381 btrfs_read_buffer(cur
, gen
);
384 if (search_start
== 0)
385 search_start
= last_block
;
387 err
= __btrfs_cow_block(trans
, root
, cur
, parent
, i
,
390 (end_slot
- i
) * blocksize
));
392 free_extent_buffer(cur
);
395 search_start
= tmp
->start
;
396 last_block
= tmp
->start
;
397 *last_ret
= search_start
;
398 if (parent_level
== 1)
399 btrfs_clear_buffer_defrag(tmp
);
400 free_extent_buffer(tmp
);
402 if (parent
->map_token
) {
403 unmap_extent_buffer(parent
, parent
->map_token
,
405 parent
->map_token
= NULL
;
412 * The leaf data grows from end-to-front in the node.
413 * this returns the address of the start of the last item,
414 * which is the stop of the leaf data stack
416 static inline unsigned int leaf_data_end(struct btrfs_root
*root
,
417 struct extent_buffer
*leaf
)
419 u32 nr
= btrfs_header_nritems(leaf
);
421 return BTRFS_LEAF_DATA_SIZE(root
);
422 return btrfs_item_offset_nr(leaf
, nr
- 1);
425 static int check_node(struct btrfs_root
*root
, struct btrfs_path
*path
,
428 struct extent_buffer
*parent
= NULL
;
429 struct extent_buffer
*node
= path
->nodes
[level
];
430 struct btrfs_disk_key parent_key
;
431 struct btrfs_disk_key node_key
;
434 struct btrfs_key cpukey
;
435 u32 nritems
= btrfs_header_nritems(node
);
437 if (path
->nodes
[level
+ 1])
438 parent
= path
->nodes
[level
+ 1];
440 slot
= path
->slots
[level
];
441 BUG_ON(nritems
== 0);
443 parent_slot
= path
->slots
[level
+ 1];
444 btrfs_node_key(parent
, &parent_key
, parent_slot
);
445 btrfs_node_key(node
, &node_key
, 0);
446 BUG_ON(memcmp(&parent_key
, &node_key
,
447 sizeof(struct btrfs_disk_key
)));
448 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
449 btrfs_header_bytenr(node
));
451 BUG_ON(nritems
> BTRFS_NODEPTRS_PER_BLOCK(root
));
453 btrfs_node_key_to_cpu(node
, &cpukey
, slot
- 1);
454 btrfs_node_key(node
, &node_key
, slot
);
455 BUG_ON(btrfs_comp_keys(&node_key
, &cpukey
) <= 0);
457 if (slot
< nritems
- 1) {
458 btrfs_node_key_to_cpu(node
, &cpukey
, slot
+ 1);
459 btrfs_node_key(node
, &node_key
, slot
);
460 BUG_ON(btrfs_comp_keys(&node_key
, &cpukey
) >= 0);
465 static int check_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
,
468 struct extent_buffer
*leaf
= path
->nodes
[level
];
469 struct extent_buffer
*parent
= NULL
;
471 struct btrfs_key cpukey
;
472 struct btrfs_disk_key parent_key
;
473 struct btrfs_disk_key leaf_key
;
474 int slot
= path
->slots
[0];
476 u32 nritems
= btrfs_header_nritems(leaf
);
478 if (path
->nodes
[level
+ 1])
479 parent
= path
->nodes
[level
+ 1];
485 parent_slot
= path
->slots
[level
+ 1];
486 btrfs_node_key(parent
, &parent_key
, parent_slot
);
487 btrfs_item_key(leaf
, &leaf_key
, 0);
489 BUG_ON(memcmp(&parent_key
, &leaf_key
,
490 sizeof(struct btrfs_disk_key
)));
491 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
492 btrfs_header_bytenr(leaf
));
495 for (i
= 0; nritems
> 1 && i
< nritems
- 2; i
++) {
496 btrfs_item_key_to_cpu(leaf
, &cpukey
, i
+ 1);
497 btrfs_item_key(leaf
, &leaf_key
, i
);
498 if (comp_keys(&leaf_key
, &cpukey
) >= 0) {
499 btrfs_print_leaf(root
, leaf
);
500 printk("slot %d offset bad key\n", i
);
503 if (btrfs_item_offset_nr(leaf
, i
) !=
504 btrfs_item_end_nr(leaf
, i
+ 1)) {
505 btrfs_print_leaf(root
, leaf
);
506 printk("slot %d offset bad\n", i
);
510 if (btrfs_item_offset_nr(leaf
, i
) +
511 btrfs_item_size_nr(leaf
, i
) !=
512 BTRFS_LEAF_DATA_SIZE(root
)) {
513 btrfs_print_leaf(root
, leaf
);
514 printk("slot %d first offset bad\n", i
);
520 if (btrfs_item_size_nr(leaf
, nritems
- 1) > 4096) {
521 btrfs_print_leaf(root
, leaf
);
522 printk("slot %d bad size \n", nritems
- 1);
527 if (slot
!= 0 && slot
< nritems
- 1) {
528 btrfs_item_key(leaf
, &leaf_key
, slot
);
529 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
- 1);
530 if (btrfs_comp_keys(&leaf_key
, &cpukey
) <= 0) {
531 btrfs_print_leaf(root
, leaf
);
532 printk("slot %d offset bad key\n", slot
);
535 if (btrfs_item_offset_nr(leaf
, slot
- 1) !=
536 btrfs_item_end_nr(leaf
, slot
)) {
537 btrfs_print_leaf(root
, leaf
);
538 printk("slot %d offset bad\n", slot
);
542 if (slot
< nritems
- 1) {
543 btrfs_item_key(leaf
, &leaf_key
, slot
);
544 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
+ 1);
545 BUG_ON(btrfs_comp_keys(&leaf_key
, &cpukey
) >= 0);
546 if (btrfs_item_offset_nr(leaf
, slot
) !=
547 btrfs_item_end_nr(leaf
, slot
+ 1)) {
548 btrfs_print_leaf(root
, leaf
);
549 printk("slot %d offset bad\n", slot
);
553 BUG_ON(btrfs_item_offset_nr(leaf
, 0) +
554 btrfs_item_size_nr(leaf
, 0) != BTRFS_LEAF_DATA_SIZE(root
));
558 static int noinline
check_block(struct btrfs_root
*root
,
559 struct btrfs_path
*path
, int level
)
563 struct extent_buffer
*buf
= path
->nodes
[level
];
565 if (memcmp_extent_buffer(buf
, root
->fs_info
->fsid
,
566 (unsigned long)btrfs_header_fsid(buf
),
568 printk("warning bad block %Lu\n", buf
->start
);
573 return check_leaf(root
, path
, level
);
574 return check_node(root
, path
, level
);
578 * search for key in the extent_buffer. The items start at offset p,
579 * and they are item_size apart. There are 'max' items in p.
581 * the slot in the array is returned via slot, and it points to
582 * the place where you would insert key if it is not found in
585 * slot may point to max if the key is bigger than all of the keys
587 static int generic_bin_search(struct extent_buffer
*eb
, unsigned long p
,
588 int item_size
, struct btrfs_key
*key
,
595 unsigned long offset
;
596 struct btrfs_disk_key
*tmp
;
599 mid
= (low
+ high
) / 2;
600 offset
= p
+ mid
* item_size
;
602 tmp
= (struct btrfs_disk_key
*)(eb
->data
+ offset
);
603 ret
= btrfs_comp_keys(tmp
, key
);
619 * simple bin_search frontend that does the right thing for
622 static int bin_search(struct extent_buffer
*eb
, struct btrfs_key
*key
,
623 int level
, int *slot
)
626 return generic_bin_search(eb
,
627 offsetof(struct btrfs_leaf
, items
),
628 sizeof(struct btrfs_item
),
629 key
, btrfs_header_nritems(eb
),
632 return generic_bin_search(eb
,
633 offsetof(struct btrfs_node
, ptrs
),
634 sizeof(struct btrfs_key_ptr
),
635 key
, btrfs_header_nritems(eb
),
641 static struct extent_buffer
*read_node_slot(struct btrfs_root
*root
,
642 struct extent_buffer
*parent
, int slot
)
644 int level
= btrfs_header_level(parent
);
647 if (slot
>= btrfs_header_nritems(parent
))
652 return read_tree_block(root
, btrfs_node_blockptr(parent
, slot
),
653 btrfs_level_size(root
, level
- 1),
654 btrfs_node_ptr_generation(parent
, slot
));
657 static int balance_level(struct btrfs_trans_handle
*trans
,
658 struct btrfs_root
*root
,
659 struct btrfs_path
*path
, int level
)
661 struct extent_buffer
*right
= NULL
;
662 struct extent_buffer
*mid
;
663 struct extent_buffer
*left
= NULL
;
664 struct extent_buffer
*parent
= NULL
;
668 int orig_slot
= path
->slots
[level
];
669 int err_on_enospc
= 0;
675 mid
= path
->nodes
[level
];
676 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
678 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
680 if (level
< BTRFS_MAX_LEVEL
- 1)
681 parent
= path
->nodes
[level
+ 1];
682 pslot
= path
->slots
[level
+ 1];
685 * deal with the case where there is only one pointer in the root
686 * by promoting the node below to a root
689 struct extent_buffer
*child
;
691 if (btrfs_header_nritems(mid
) != 1)
694 /* promote the child to a root */
695 child
= read_node_slot(root
, mid
, 0);
697 ret
= btrfs_cow_block(trans
, root
, child
, mid
, 0, &child
);
702 ret
= btrfs_update_extent_ref(trans
, root
, child
->start
,
703 mid
->start
, child
->start
,
704 root
->root_key
.objectid
,
705 trans
->transid
, level
- 1);
708 add_root_to_dirty_list(root
);
709 path
->nodes
[level
] = NULL
;
710 clean_tree_block(trans
, root
, mid
);
711 wait_on_tree_block_writeback(root
, mid
);
712 /* once for the path */
713 free_extent_buffer(mid
);
714 ret
= btrfs_free_extent(trans
, root
, mid
->start
, mid
->len
,
715 mid
->start
, root
->root_key
.objectid
,
716 btrfs_header_generation(mid
),
718 /* once for the root ptr */
719 free_extent_buffer(mid
);
722 if (btrfs_header_nritems(mid
) >
723 BTRFS_NODEPTRS_PER_BLOCK(root
) / 4)
726 if (btrfs_header_nritems(mid
) < 2)
729 left
= read_node_slot(root
, parent
, pslot
- 1);
731 wret
= btrfs_cow_block(trans
, root
, left
,
732 parent
, pslot
- 1, &left
);
738 right
= read_node_slot(root
, parent
, pslot
+ 1);
740 wret
= btrfs_cow_block(trans
, root
, right
,
741 parent
, pslot
+ 1, &right
);
748 /* first, try to make some room in the middle buffer */
750 orig_slot
+= btrfs_header_nritems(left
);
751 wret
= push_node_left(trans
, root
, left
, mid
, 1);
754 if (btrfs_header_nritems(mid
) < 2)
759 * then try to empty the right most buffer into the middle
762 wret
= push_node_left(trans
, root
, mid
, right
, 1);
763 if (wret
< 0 && wret
!= -ENOSPC
)
765 if (btrfs_header_nritems(right
) == 0) {
766 u64 bytenr
= right
->start
;
767 u64 generation
= btrfs_header_generation(parent
);
768 u32 blocksize
= right
->len
;
770 clean_tree_block(trans
, root
, right
);
771 wait_on_tree_block_writeback(root
, right
);
772 free_extent_buffer(right
);
774 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
+
778 wret
= btrfs_free_extent(trans
, root
, bytenr
,
779 blocksize
, parent
->start
,
780 btrfs_header_owner(parent
),
781 generation
, level
, 1);
785 struct btrfs_disk_key right_key
;
786 btrfs_node_key(right
, &right_key
, 0);
787 btrfs_set_node_key(parent
, &right_key
, pslot
+ 1);
788 btrfs_mark_buffer_dirty(parent
);
791 if (btrfs_header_nritems(mid
) == 1) {
793 * we're not allowed to leave a node with one item in the
794 * tree during a delete. A deletion from lower in the tree
795 * could try to delete the only pointer in this node.
796 * So, pull some keys from the left.
797 * There has to be a left pointer at this point because
798 * otherwise we would have pulled some pointers from the
802 wret
= balance_node_right(trans
, root
, mid
, left
);
808 wret
= push_node_left(trans
, root
, left
, mid
, 1);
814 if (btrfs_header_nritems(mid
) == 0) {
815 /* we've managed to empty the middle node, drop it */
816 u64 root_gen
= btrfs_header_generation(parent
);
817 u64 bytenr
= mid
->start
;
818 u32 blocksize
= mid
->len
;
819 clean_tree_block(trans
, root
, mid
);
820 wait_on_tree_block_writeback(root
, mid
);
821 free_extent_buffer(mid
);
823 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
);
826 wret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
,
828 btrfs_header_owner(parent
),
833 /* update the parent key to reflect our changes */
834 struct btrfs_disk_key mid_key
;
835 btrfs_node_key(mid
, &mid_key
, 0);
836 btrfs_set_node_key(parent
, &mid_key
, pslot
);
837 btrfs_mark_buffer_dirty(parent
);
840 /* update the path */
842 if (btrfs_header_nritems(left
) > orig_slot
) {
843 extent_buffer_get(left
);
844 path
->nodes
[level
] = left
;
845 path
->slots
[level
+ 1] -= 1;
846 path
->slots
[level
] = orig_slot
;
848 free_extent_buffer(mid
);
850 orig_slot
-= btrfs_header_nritems(left
);
851 path
->slots
[level
] = orig_slot
;
854 /* double check we haven't messed things up */
855 check_block(root
, path
, level
);
857 btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]))
861 free_extent_buffer(right
);
863 free_extent_buffer(left
);
867 /* returns zero if the push worked, non-zero otherwise */
868 static int noinline
push_nodes_for_insert(struct btrfs_trans_handle
*trans
,
869 struct btrfs_root
*root
,
870 struct btrfs_path
*path
, int level
)
872 struct extent_buffer
*right
= NULL
;
873 struct extent_buffer
*mid
;
874 struct extent_buffer
*left
= NULL
;
875 struct extent_buffer
*parent
= NULL
;
879 int orig_slot
= path
->slots
[level
];
885 mid
= path
->nodes
[level
];
886 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
887 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
889 if (level
< BTRFS_MAX_LEVEL
- 1)
890 parent
= path
->nodes
[level
+ 1];
891 pslot
= path
->slots
[level
+ 1];
896 left
= read_node_slot(root
, parent
, pslot
- 1);
898 /* first, try to make some room in the middle buffer */
901 left_nr
= btrfs_header_nritems(left
);
902 if (left_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
905 ret
= btrfs_cow_block(trans
, root
, left
, parent
,
910 wret
= push_node_left(trans
, root
,
917 struct btrfs_disk_key disk_key
;
918 orig_slot
+= left_nr
;
919 btrfs_node_key(mid
, &disk_key
, 0);
920 btrfs_set_node_key(parent
, &disk_key
, pslot
);
921 btrfs_mark_buffer_dirty(parent
);
922 if (btrfs_header_nritems(left
) > orig_slot
) {
923 path
->nodes
[level
] = left
;
924 path
->slots
[level
+ 1] -= 1;
925 path
->slots
[level
] = orig_slot
;
926 free_extent_buffer(mid
);
929 btrfs_header_nritems(left
);
930 path
->slots
[level
] = orig_slot
;
931 free_extent_buffer(left
);
935 free_extent_buffer(left
);
937 right
= read_node_slot(root
, parent
, pslot
+ 1);
940 * then try to empty the right most buffer into the middle
944 right_nr
= btrfs_header_nritems(right
);
945 if (right_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
948 ret
= btrfs_cow_block(trans
, root
, right
,
954 wret
= balance_node_right(trans
, root
,
961 struct btrfs_disk_key disk_key
;
963 btrfs_node_key(right
, &disk_key
, 0);
964 btrfs_set_node_key(parent
, &disk_key
, pslot
+ 1);
965 btrfs_mark_buffer_dirty(parent
);
967 if (btrfs_header_nritems(mid
) <= orig_slot
) {
968 path
->nodes
[level
] = right
;
969 path
->slots
[level
+ 1] += 1;
970 path
->slots
[level
] = orig_slot
-
971 btrfs_header_nritems(mid
);
972 free_extent_buffer(mid
);
974 free_extent_buffer(right
);
978 free_extent_buffer(right
);
984 * readahead one full node of leaves
986 static void reada_for_search(struct btrfs_root
*root
, struct btrfs_path
*path
,
987 int level
, int slot
, u64 objectid
)
989 struct extent_buffer
*node
;
990 struct btrfs_disk_key disk_key
;
996 int direction
= path
->reada
;
997 struct extent_buffer
*eb
;
1005 if (!path
->nodes
[level
])
1008 node
= path
->nodes
[level
];
1009 search
= btrfs_node_blockptr(node
, slot
);
1010 blocksize
= btrfs_level_size(root
, level
- 1);
1011 eb
= btrfs_find_tree_block(root
, search
, blocksize
);
1013 free_extent_buffer(eb
);
1017 highest_read
= search
;
1018 lowest_read
= search
;
1020 nritems
= btrfs_header_nritems(node
);
1023 if (direction
< 0) {
1027 } else if (direction
> 0) {
1032 if (path
->reada
< 0 && objectid
) {
1033 btrfs_node_key(node
, &disk_key
, nr
);
1034 if (btrfs_disk_key_objectid(&disk_key
) != objectid
)
1037 search
= btrfs_node_blockptr(node
, nr
);
1038 if ((search
>= lowest_read
&& search
<= highest_read
) ||
1039 (search
< lowest_read
&& lowest_read
- search
<= 32768) ||
1040 (search
> highest_read
&& search
- highest_read
<= 32768)) {
1041 readahead_tree_block(root
, search
, blocksize
,
1042 btrfs_node_ptr_generation(node
, nr
));
1046 if (path
->reada
< 2 && (nread
> (256 * 1024) || nscan
> 32))
1048 if(nread
> (1024 * 1024) || nscan
> 128)
1051 if (search
< lowest_read
)
1052 lowest_read
= search
;
1053 if (search
> highest_read
)
1054 highest_read
= search
;
1059 * look for key in the tree. path is filled in with nodes along the way
1060 * if key is found, we return zero and you can find the item in the leaf
1061 * level of the path (level 0)
1063 * If the key isn't found, the path points to the slot where it should
1064 * be inserted, and 1 is returned. If there are other errors during the
1065 * search a negative error number is returned.
1067 * if ins_len > 0, nodes and leaves will be split as we walk down the
1068 * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
1071 int btrfs_search_slot(struct btrfs_trans_handle
*trans
, struct btrfs_root
1072 *root
, struct btrfs_key
*key
, struct btrfs_path
*p
, int
1075 struct extent_buffer
*b
;
1079 int should_reada
= p
->reada
;
1080 u8 lowest_level
= 0;
1082 lowest_level
= p
->lowest_level
;
1083 WARN_ON(lowest_level
&& ins_len
);
1084 WARN_ON(p
->nodes
[0] != NULL
);
1086 WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
1090 extent_buffer_get(b
);
1092 level
= btrfs_header_level(b
);
1095 wret
= btrfs_cow_block(trans
, root
, b
,
1096 p
->nodes
[level
+ 1],
1097 p
->slots
[level
+ 1],
1100 free_extent_buffer(b
);
1104 BUG_ON(!cow
&& ins_len
);
1105 if (level
!= btrfs_header_level(b
))
1107 level
= btrfs_header_level(b
);
1108 p
->nodes
[level
] = b
;
1109 ret
= check_block(root
, p
, level
);
1112 ret
= bin_search(b
, key
, level
, &slot
);
1114 if (ret
&& slot
> 0)
1116 p
->slots
[level
] = slot
;
1117 if ((p
->search_for_split
|| ins_len
> 0) &&
1118 btrfs_header_nritems(b
) >=
1119 BTRFS_NODEPTRS_PER_BLOCK(root
) - 3) {
1120 int sret
= split_node(trans
, root
, p
, level
);
1124 b
= p
->nodes
[level
];
1125 slot
= p
->slots
[level
];
1126 } else if (ins_len
< 0) {
1127 int sret
= balance_level(trans
, root
, p
,
1131 b
= p
->nodes
[level
];
1133 btrfs_release_path(NULL
, p
);
1136 slot
= p
->slots
[level
];
1137 BUG_ON(btrfs_header_nritems(b
) == 1);
1139 /* this is only true while dropping a snapshot */
1140 if (level
== lowest_level
)
1144 reada_for_search(root
, p
, level
, slot
,
1147 b
= read_node_slot(root
, b
, slot
);
1149 p
->slots
[level
] = slot
;
1150 if (ins_len
> 0 && btrfs_leaf_free_space(root
, b
) <
1151 sizeof(struct btrfs_item
) + ins_len
) {
1152 int sret
= split_leaf(trans
, root
, key
,
1153 p
, ins_len
, ret
== 0);
1165 * adjust the pointers going up the tree, starting at level
1166 * making sure the right key of each node is points to 'key'.
1167 * This is used after shifting pointers to the left, so it stops
1168 * fixing up pointers when a given leaf/node is not in slot 0 of the
1171 * If this fails to write a tree block, it returns -1, but continues
1172 * fixing up the blocks in ram so the tree is consistent.
1174 static int fixup_low_keys(struct btrfs_trans_handle
*trans
,
1175 struct btrfs_root
*root
, struct btrfs_path
*path
,
1176 struct btrfs_disk_key
*key
, int level
)
1180 struct extent_buffer
*t
;
1182 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1183 int tslot
= path
->slots
[i
];
1184 if (!path
->nodes
[i
])
1187 btrfs_set_node_key(t
, key
, tslot
);
1188 btrfs_mark_buffer_dirty(path
->nodes
[i
]);
1198 * This function isn't completely safe. It's the caller's responsibility
1199 * that the new key won't break the order
1201 int btrfs_set_item_key_safe(struct btrfs_trans_handle
*trans
,
1202 struct btrfs_root
*root
, struct btrfs_path
*path
,
1203 struct btrfs_key
*new_key
)
1205 struct btrfs_disk_key disk_key
;
1206 struct extent_buffer
*eb
;
1209 eb
= path
->nodes
[0];
1210 slot
= path
->slots
[0];
1212 btrfs_item_key(eb
, &disk_key
, slot
- 1);
1213 if (btrfs_comp_keys(&disk_key
, new_key
) >= 0)
1216 if (slot
< btrfs_header_nritems(eb
) - 1) {
1217 btrfs_item_key(eb
, &disk_key
, slot
+ 1);
1218 if (btrfs_comp_keys(&disk_key
, new_key
) <= 0)
1222 btrfs_cpu_key_to_disk(&disk_key
, new_key
);
1223 btrfs_set_item_key(eb
, &disk_key
, slot
);
1224 btrfs_mark_buffer_dirty(eb
);
1226 fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1231 * try to push data from one node into the next node left in the
1234 * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
1235 * error, and > 0 if there was no room in the left hand block.
1237 static int push_node_left(struct btrfs_trans_handle
*trans
,
1238 struct btrfs_root
*root
, struct extent_buffer
*dst
,
1239 struct extent_buffer
*src
, int empty
)
1246 src_nritems
= btrfs_header_nritems(src
);
1247 dst_nritems
= btrfs_header_nritems(dst
);
1248 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1249 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1250 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1252 if (!empty
&& src_nritems
<= 8)
1255 if (push_items
<= 0) {
1260 push_items
= min(src_nritems
, push_items
);
1261 if (push_items
< src_nritems
) {
1262 /* leave at least 8 pointers in the node if
1263 * we aren't going to empty it
1265 if (src_nritems
- push_items
< 8) {
1266 if (push_items
<= 8)
1272 push_items
= min(src_nritems
- 8, push_items
);
1274 copy_extent_buffer(dst
, src
,
1275 btrfs_node_key_ptr_offset(dst_nritems
),
1276 btrfs_node_key_ptr_offset(0),
1277 push_items
* sizeof(struct btrfs_key_ptr
));
1279 if (push_items
< src_nritems
) {
1280 memmove_extent_buffer(src
, btrfs_node_key_ptr_offset(0),
1281 btrfs_node_key_ptr_offset(push_items
),
1282 (src_nritems
- push_items
) *
1283 sizeof(struct btrfs_key_ptr
));
1285 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1286 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1287 btrfs_mark_buffer_dirty(src
);
1288 btrfs_mark_buffer_dirty(dst
);
1290 ret
= btrfs_update_ref(trans
, root
, src
, dst
, dst_nritems
, push_items
);
1296 * try to push data from one node into the next node right in the
1299 * returns 0 if some ptrs were pushed, < 0 if there was some horrible
1300 * error, and > 0 if there was no room in the right hand block.
1302 * this will only push up to 1/2 the contents of the left node over
1304 static int balance_node_right(struct btrfs_trans_handle
*trans
,
1305 struct btrfs_root
*root
,
1306 struct extent_buffer
*dst
,
1307 struct extent_buffer
*src
)
1315 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1316 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1318 src_nritems
= btrfs_header_nritems(src
);
1319 dst_nritems
= btrfs_header_nritems(dst
);
1320 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1321 if (push_items
<= 0) {
1325 if (src_nritems
< 4) {
1329 max_push
= src_nritems
/ 2 + 1;
1330 /* don't try to empty the node */
1331 if (max_push
>= src_nritems
) {
1335 if (max_push
< push_items
)
1336 push_items
= max_push
;
1338 memmove_extent_buffer(dst
, btrfs_node_key_ptr_offset(push_items
),
1339 btrfs_node_key_ptr_offset(0),
1341 sizeof(struct btrfs_key_ptr
));
1343 copy_extent_buffer(dst
, src
,
1344 btrfs_node_key_ptr_offset(0),
1345 btrfs_node_key_ptr_offset(src_nritems
- push_items
),
1346 push_items
* sizeof(struct btrfs_key_ptr
));
1348 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1349 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1351 btrfs_mark_buffer_dirty(src
);
1352 btrfs_mark_buffer_dirty(dst
);
1354 ret
= btrfs_update_ref(trans
, root
, src
, dst
, 0, push_items
);
1360 * helper function to insert a new root level in the tree.
1361 * A new node is allocated, and a single item is inserted to
1362 * point to the existing root
1364 * returns zero on success or < 0 on failure.
1366 static int noinline
insert_new_root(struct btrfs_trans_handle
*trans
,
1367 struct btrfs_root
*root
,
1368 struct btrfs_path
*path
, int level
)
1371 struct extent_buffer
*lower
;
1372 struct extent_buffer
*c
;
1373 struct extent_buffer
*old
;
1374 struct btrfs_disk_key lower_key
;
1377 BUG_ON(path
->nodes
[level
]);
1378 BUG_ON(path
->nodes
[level
-1] != root
->node
);
1380 lower
= path
->nodes
[level
-1];
1382 btrfs_item_key(lower
, &lower_key
, 0);
1384 btrfs_node_key(lower
, &lower_key
, 0);
1386 c
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
, 0,
1387 root
->root_key
.objectid
,
1388 trans
->transid
, level
,
1389 root
->node
->start
, 0);
1393 memset_extent_buffer(c
, 0, 0, root
->nodesize
);
1394 btrfs_set_header_nritems(c
, 1);
1395 btrfs_set_header_level(c
, level
);
1396 btrfs_set_header_bytenr(c
, c
->start
);
1397 btrfs_set_header_generation(c
, trans
->transid
);
1398 btrfs_set_header_owner(c
, root
->root_key
.objectid
);
1400 write_extent_buffer(c
, root
->fs_info
->fsid
,
1401 (unsigned long)btrfs_header_fsid(c
),
1404 write_extent_buffer(c
, root
->fs_info
->chunk_tree_uuid
,
1405 (unsigned long)btrfs_header_chunk_tree_uuid(c
),
1408 btrfs_set_node_key(c
, &lower_key
, 0);
1409 btrfs_set_node_blockptr(c
, 0, lower
->start
);
1410 lower_gen
= btrfs_header_generation(lower
);
1411 WARN_ON(lower_gen
!= trans
->transid
);
1413 btrfs_set_node_ptr_generation(c
, 0, lower_gen
);
1415 btrfs_mark_buffer_dirty(c
);
1420 ret
= btrfs_update_extent_ref(trans
, root
, lower
->start
,
1421 lower
->start
, c
->start
,
1422 root
->root_key
.objectid
,
1423 trans
->transid
, level
- 1);
1426 /* the super has an extra ref to root->node */
1427 free_extent_buffer(old
);
1429 add_root_to_dirty_list(root
);
1430 extent_buffer_get(c
);
1431 path
->nodes
[level
] = c
;
1432 path
->slots
[level
] = 0;
1437 * worker function to insert a single pointer in a node.
1438 * the node should have enough room for the pointer already
1440 * slot and level indicate where you want the key to go, and
1441 * blocknr is the block the key points to.
1443 * returns zero on success and < 0 on any error
1445 static int insert_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
1446 *root
, struct btrfs_path
*path
, struct btrfs_disk_key
1447 *key
, u64 bytenr
, int slot
, int level
)
1449 struct extent_buffer
*lower
;
1452 BUG_ON(!path
->nodes
[level
]);
1453 lower
= path
->nodes
[level
];
1454 nritems
= btrfs_header_nritems(lower
);
1457 if (nritems
== BTRFS_NODEPTRS_PER_BLOCK(root
))
1459 if (slot
!= nritems
) {
1460 memmove_extent_buffer(lower
,
1461 btrfs_node_key_ptr_offset(slot
+ 1),
1462 btrfs_node_key_ptr_offset(slot
),
1463 (nritems
- slot
) * sizeof(struct btrfs_key_ptr
));
1465 btrfs_set_node_key(lower
, key
, slot
);
1466 btrfs_set_node_blockptr(lower
, slot
, bytenr
);
1467 WARN_ON(trans
->transid
== 0);
1468 btrfs_set_node_ptr_generation(lower
, slot
, trans
->transid
);
1469 btrfs_set_header_nritems(lower
, nritems
+ 1);
1470 btrfs_mark_buffer_dirty(lower
);
1475 * split the node at the specified level in path in two.
1476 * The path is corrected to point to the appropriate node after the split
1478 * Before splitting this tries to make some room in the node by pushing
1479 * left and right, if either one works, it returns right away.
1481 * returns 0 on success and < 0 on failure
1483 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
1484 *root
, struct btrfs_path
*path
, int level
)
1486 struct extent_buffer
*c
;
1487 struct extent_buffer
*split
;
1488 struct btrfs_disk_key disk_key
;
1494 c
= path
->nodes
[level
];
1495 WARN_ON(btrfs_header_generation(c
) != trans
->transid
);
1496 if (c
== root
->node
) {
1497 /* trying to split the root, lets make a new one */
1498 ret
= insert_new_root(trans
, root
, path
, level
+ 1);
1502 ret
= push_nodes_for_insert(trans
, root
, path
, level
);
1503 c
= path
->nodes
[level
];
1504 if (!ret
&& btrfs_header_nritems(c
) <
1505 BTRFS_NODEPTRS_PER_BLOCK(root
) - 3)
1511 c_nritems
= btrfs_header_nritems(c
);
1513 btrfs_node_key(c
, &disk_key
, 0);
1514 split
= btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1515 path
->nodes
[level
+ 1]->start
,
1516 root
->root_key
.objectid
,
1517 trans
->transid
, level
, c
->start
, 0);
1519 return PTR_ERR(split
);
1521 btrfs_set_header_flags(split
, btrfs_header_flags(c
));
1522 btrfs_set_header_level(split
, btrfs_header_level(c
));
1523 btrfs_set_header_bytenr(split
, split
->start
);
1524 btrfs_set_header_generation(split
, trans
->transid
);
1525 btrfs_set_header_owner(split
, root
->root_key
.objectid
);
1526 btrfs_set_header_flags(split
, 0);
1527 write_extent_buffer(split
, root
->fs_info
->fsid
,
1528 (unsigned long)btrfs_header_fsid(split
),
1530 write_extent_buffer(split
, root
->fs_info
->chunk_tree_uuid
,
1531 (unsigned long)btrfs_header_chunk_tree_uuid(split
),
1534 mid
= (c_nritems
+ 1) / 2;
1536 copy_extent_buffer(split
, c
,
1537 btrfs_node_key_ptr_offset(0),
1538 btrfs_node_key_ptr_offset(mid
),
1539 (c_nritems
- mid
) * sizeof(struct btrfs_key_ptr
));
1540 btrfs_set_header_nritems(split
, c_nritems
- mid
);
1541 btrfs_set_header_nritems(c
, mid
);
1544 btrfs_mark_buffer_dirty(c
);
1545 btrfs_mark_buffer_dirty(split
);
1547 btrfs_node_key(split
, &disk_key
, 0);
1548 wret
= insert_ptr(trans
, root
, path
, &disk_key
, split
->start
,
1549 path
->slots
[level
+ 1] + 1,
1554 ret
= btrfs_update_ref(trans
, root
, c
, split
, 0, c_nritems
- mid
);
1557 if (path
->slots
[level
] >= mid
) {
1558 path
->slots
[level
] -= mid
;
1559 free_extent_buffer(c
);
1560 path
->nodes
[level
] = split
;
1561 path
->slots
[level
+ 1] += 1;
1563 free_extent_buffer(split
);
1569 * how many bytes are required to store the items in a leaf. start
1570 * and nr indicate which items in the leaf to check. This totals up the
1571 * space used both by the item structs and the item data
1573 static int leaf_space_used(struct extent_buffer
*l
, int start
, int nr
)
1576 int nritems
= btrfs_header_nritems(l
);
1577 int end
= min(nritems
, start
+ nr
) - 1;
1581 data_len
= btrfs_item_end_nr(l
, start
);
1582 data_len
= data_len
- btrfs_item_offset_nr(l
, end
);
1583 data_len
+= sizeof(struct btrfs_item
) * nr
;
1584 WARN_ON(data_len
< 0);
1589 * The space between the end of the leaf items and
1590 * the start of the leaf data. IOW, how much room
1591 * the leaf has left for both items and data
1593 int btrfs_leaf_free_space(struct btrfs_root
*root
, struct extent_buffer
*leaf
)
1595 int nritems
= btrfs_header_nritems(leaf
);
1597 ret
= BTRFS_LEAF_DATA_SIZE(root
) - leaf_space_used(leaf
, 0, nritems
);
1599 printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
1600 ret
, (unsigned long) BTRFS_LEAF_DATA_SIZE(root
),
1601 leaf_space_used(leaf
, 0, nritems
), nritems
);
1607 * push some data in the path leaf to the right, trying to free up at
1608 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1610 * returns 1 if the push failed because the other node didn't have enough
1611 * room, 0 if everything worked out and < 0 if there were major errors.
1613 static int push_leaf_right(struct btrfs_trans_handle
*trans
, struct btrfs_root
1614 *root
, struct btrfs_path
*path
, int data_size
,
1617 struct extent_buffer
*left
= path
->nodes
[0];
1618 struct extent_buffer
*right
;
1619 struct extent_buffer
*upper
;
1620 struct btrfs_disk_key disk_key
;
1626 struct btrfs_item
*item
;
1634 slot
= path
->slots
[1];
1635 if (!path
->nodes
[1]) {
1638 upper
= path
->nodes
[1];
1639 if (slot
>= btrfs_header_nritems(upper
) - 1)
1642 right
= read_node_slot(root
, upper
, slot
+ 1);
1643 free_space
= btrfs_leaf_free_space(root
, right
);
1644 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1645 free_extent_buffer(right
);
1649 /* cow and double check */
1650 ret
= btrfs_cow_block(trans
, root
, right
, upper
,
1653 free_extent_buffer(right
);
1656 free_space
= btrfs_leaf_free_space(root
, right
);
1657 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1658 free_extent_buffer(right
);
1662 left_nritems
= btrfs_header_nritems(left
);
1663 if (left_nritems
== 0) {
1664 free_extent_buffer(right
);
1673 i
= left_nritems
- 1;
1675 item
= btrfs_item_nr(left
, i
);
1677 if (path
->slots
[0] == i
)
1678 push_space
+= data_size
+ sizeof(*item
);
1680 this_item_size
= btrfs_item_size(left
, item
);
1681 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1684 push_space
+= this_item_size
+ sizeof(*item
);
1690 if (push_items
== 0) {
1691 free_extent_buffer(right
);
1695 if (!empty
&& push_items
== left_nritems
)
1698 /* push left to right */
1699 right_nritems
= btrfs_header_nritems(right
);
1701 push_space
= btrfs_item_end_nr(left
, left_nritems
- push_items
);
1702 push_space
-= leaf_data_end(root
, left
);
1704 /* make room in the right data area */
1705 data_end
= leaf_data_end(root
, right
);
1706 memmove_extent_buffer(right
,
1707 btrfs_leaf_data(right
) + data_end
- push_space
,
1708 btrfs_leaf_data(right
) + data_end
,
1709 BTRFS_LEAF_DATA_SIZE(root
) - data_end
);
1711 /* copy from the left data area */
1712 copy_extent_buffer(right
, left
, btrfs_leaf_data(right
) +
1713 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1714 btrfs_leaf_data(left
) + leaf_data_end(root
, left
),
1717 memmove_extent_buffer(right
, btrfs_item_nr_offset(push_items
),
1718 btrfs_item_nr_offset(0),
1719 right_nritems
* sizeof(struct btrfs_item
));
1721 /* copy the items from left to right */
1722 copy_extent_buffer(right
, left
, btrfs_item_nr_offset(0),
1723 btrfs_item_nr_offset(left_nritems
- push_items
),
1724 push_items
* sizeof(struct btrfs_item
));
1726 /* update the item pointers */
1727 right_nritems
+= push_items
;
1728 btrfs_set_header_nritems(right
, right_nritems
);
1729 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1730 for (i
= 0; i
< right_nritems
; i
++) {
1731 item
= btrfs_item_nr(right
, i
);
1732 push_space
-= btrfs_item_size(right
, item
);
1733 btrfs_set_item_offset(right
, item
, push_space
);
1736 left_nritems
-= push_items
;
1737 btrfs_set_header_nritems(left
, left_nritems
);
1740 btrfs_mark_buffer_dirty(left
);
1741 btrfs_mark_buffer_dirty(right
);
1743 btrfs_item_key(right
, &disk_key
, 0);
1744 btrfs_set_node_key(upper
, &disk_key
, slot
+ 1);
1745 btrfs_mark_buffer_dirty(upper
);
1747 ret
= btrfs_update_ref(trans
, root
, left
, right
, 0, push_items
);
1750 /* then fixup the leaf pointer in the path */
1751 if (path
->slots
[0] >= left_nritems
) {
1752 path
->slots
[0] -= left_nritems
;
1753 free_extent_buffer(path
->nodes
[0]);
1754 path
->nodes
[0] = right
;
1755 path
->slots
[1] += 1;
1757 free_extent_buffer(right
);
1762 * push some data in the path leaf to the left, trying to free up at
1763 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1765 static int push_leaf_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1766 *root
, struct btrfs_path
*path
, int data_size
,
1769 struct btrfs_disk_key disk_key
;
1770 struct extent_buffer
*right
= path
->nodes
[0];
1771 struct extent_buffer
*left
;
1777 struct btrfs_item
*item
;
1778 u32 old_left_nritems
;
1784 u32 old_left_item_size
;
1786 slot
= path
->slots
[1];
1789 if (!path
->nodes
[1])
1792 right_nritems
= btrfs_header_nritems(right
);
1793 if (right_nritems
== 0) {
1797 left
= read_node_slot(root
, path
->nodes
[1], slot
- 1);
1798 free_space
= btrfs_leaf_free_space(root
, left
);
1799 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1800 free_extent_buffer(left
);
1804 /* cow and double check */
1805 ret
= btrfs_cow_block(trans
, root
, left
,
1806 path
->nodes
[1], slot
- 1, &left
);
1808 /* we hit -ENOSPC, but it isn't fatal here */
1809 free_extent_buffer(left
);
1813 free_space
= btrfs_leaf_free_space(root
, left
);
1814 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1815 free_extent_buffer(left
);
1822 nr
= right_nritems
- 1;
1824 for (i
= 0; i
< nr
; i
++) {
1825 item
= btrfs_item_nr(right
, i
);
1827 if (path
->slots
[0] == i
)
1828 push_space
+= data_size
+ sizeof(*item
);
1830 this_item_size
= btrfs_item_size(right
, item
);
1831 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1835 push_space
+= this_item_size
+ sizeof(*item
);
1838 if (push_items
== 0) {
1839 free_extent_buffer(left
);
1842 if (!empty
&& push_items
== btrfs_header_nritems(right
))
1845 /* push data from right to left */
1846 copy_extent_buffer(left
, right
,
1847 btrfs_item_nr_offset(btrfs_header_nritems(left
)),
1848 btrfs_item_nr_offset(0),
1849 push_items
* sizeof(struct btrfs_item
));
1851 push_space
= BTRFS_LEAF_DATA_SIZE(root
) -
1852 btrfs_item_offset_nr(right
, push_items
-1);
1854 copy_extent_buffer(left
, right
, btrfs_leaf_data(left
) +
1855 leaf_data_end(root
, left
) - push_space
,
1856 btrfs_leaf_data(right
) +
1857 btrfs_item_offset_nr(right
, push_items
- 1),
1859 old_left_nritems
= btrfs_header_nritems(left
);
1860 BUG_ON(old_left_nritems
< 0);
1862 old_left_item_size
= btrfs_item_offset_nr(left
, old_left_nritems
- 1);
1863 for (i
= old_left_nritems
; i
< old_left_nritems
+ push_items
; i
++) {
1866 item
= btrfs_item_nr(left
, i
);
1867 ioff
= btrfs_item_offset(left
, item
);
1868 btrfs_set_item_offset(left
, item
,
1869 ioff
- (BTRFS_LEAF_DATA_SIZE(root
) - old_left_item_size
));
1871 btrfs_set_header_nritems(left
, old_left_nritems
+ push_items
);
1873 /* fixup right node */
1874 if (push_items
> right_nritems
) {
1875 printk("push items %d nr %u\n", push_items
, right_nritems
);
1879 if (push_items
< right_nritems
) {
1880 push_space
= btrfs_item_offset_nr(right
, push_items
- 1) -
1881 leaf_data_end(root
, right
);
1882 memmove_extent_buffer(right
, btrfs_leaf_data(right
) +
1883 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1884 btrfs_leaf_data(right
) +
1885 leaf_data_end(root
, right
), push_space
);
1887 memmove_extent_buffer(right
, btrfs_item_nr_offset(0),
1888 btrfs_item_nr_offset(push_items
),
1889 (btrfs_header_nritems(right
) - push_items
) *
1890 sizeof(struct btrfs_item
));
1892 right_nritems
-= push_items
;
1893 btrfs_set_header_nritems(right
, right_nritems
);
1894 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1895 for (i
= 0; i
< right_nritems
; i
++) {
1896 item
= btrfs_item_nr(right
, i
);
1897 push_space
= push_space
- btrfs_item_size(right
, item
);
1898 btrfs_set_item_offset(right
, item
, push_space
);
1901 btrfs_mark_buffer_dirty(left
);
1903 btrfs_mark_buffer_dirty(right
);
1905 btrfs_item_key(right
, &disk_key
, 0);
1906 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1910 ret
= btrfs_update_ref(trans
, root
, right
, left
,
1911 old_left_nritems
, push_items
);
1914 /* then fixup the leaf pointer in the path */
1915 if (path
->slots
[0] < push_items
) {
1916 path
->slots
[0] += old_left_nritems
;
1917 free_extent_buffer(path
->nodes
[0]);
1918 path
->nodes
[0] = left
;
1919 path
->slots
[1] -= 1;
1921 free_extent_buffer(left
);
1922 path
->slots
[0] -= push_items
;
1924 BUG_ON(path
->slots
[0] < 0);
1929 * split the path's leaf in two, making sure there is at least data_size
1930 * available for the resulting leaf level of the path.
1932 * returns 0 if all went well and < 0 on failure.
1934 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
1935 *root
, struct btrfs_key
*ins_key
,
1936 struct btrfs_path
*path
, int data_size
, int extend
)
1938 struct extent_buffer
*l
;
1942 struct extent_buffer
*right
;
1943 int space_needed
= data_size
+ sizeof(struct btrfs_item
);
1950 int num_doubles
= 0;
1951 struct btrfs_disk_key disk_key
;
1953 if (extend
&& data_size
)
1954 space_needed
= data_size
;
1956 /* first try to make some room by pushing left and right */
1957 if (data_size
&& ins_key
->type
!= BTRFS_DIR_ITEM_KEY
) {
1958 wret
= push_leaf_right(trans
, root
, path
, data_size
, 0);
1963 wret
= push_leaf_left(trans
, root
, path
, data_size
, 0);
1969 /* did the pushes work? */
1970 if (btrfs_leaf_free_space(root
, l
) >= space_needed
)
1974 if (!path
->nodes
[1]) {
1975 ret
= insert_new_root(trans
, root
, path
, 1);
1982 slot
= path
->slots
[0];
1983 nritems
= btrfs_header_nritems(l
);
1984 mid
= (nritems
+ 1)/ 2;
1986 right
= btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
1987 path
->nodes
[1]->start
,
1988 root
->root_key
.objectid
,
1989 trans
->transid
, 0, l
->start
, 0);
1990 if (IS_ERR(right
)) {
1992 return PTR_ERR(right
);
1995 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
1996 btrfs_set_header_bytenr(right
, right
->start
);
1997 btrfs_set_header_generation(right
, trans
->transid
);
1998 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
1999 btrfs_set_header_level(right
, 0);
2000 write_extent_buffer(right
, root
->fs_info
->fsid
,
2001 (unsigned long)btrfs_header_fsid(right
),
2004 write_extent_buffer(right
, root
->fs_info
->chunk_tree_uuid
,
2005 (unsigned long)btrfs_header_chunk_tree_uuid(right
),
2009 leaf_space_used(l
, mid
, nritems
- mid
) + space_needed
>
2010 BTRFS_LEAF_DATA_SIZE(root
)) {
2011 if (slot
>= nritems
) {
2012 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2013 btrfs_set_header_nritems(right
, 0);
2014 wret
= insert_ptr(trans
, root
, path
,
2015 &disk_key
, right
->start
,
2016 path
->slots
[1] + 1, 1);
2019 free_extent_buffer(path
->nodes
[0]);
2020 path
->nodes
[0] = right
;
2022 path
->slots
[1] += 1;
2026 if (mid
!= nritems
&&
2027 leaf_space_used(l
, mid
, nritems
- mid
) +
2028 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2033 if (leaf_space_used(l
, 0, mid
+ 1) + space_needed
>
2034 BTRFS_LEAF_DATA_SIZE(root
)) {
2035 if (!extend
&& data_size
&& slot
== 0) {
2036 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2037 btrfs_set_header_nritems(right
, 0);
2038 wret
= insert_ptr(trans
, root
, path
,
2044 free_extent_buffer(path
->nodes
[0]);
2045 path
->nodes
[0] = right
;
2047 if (path
->slots
[1] == 0) {
2048 wret
= fixup_low_keys(trans
, root
,
2049 path
, &disk_key
, 1);
2054 } else if ((extend
|| !data_size
) && slot
== 0) {
2058 if (mid
!= nritems
&&
2059 leaf_space_used(l
, mid
, nritems
- mid
) +
2060 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2066 nritems
= nritems
- mid
;
2067 btrfs_set_header_nritems(right
, nritems
);
2068 data_copy_size
= btrfs_item_end_nr(l
, mid
) - leaf_data_end(root
, l
);
2070 copy_extent_buffer(right
, l
, btrfs_item_nr_offset(0),
2071 btrfs_item_nr_offset(mid
),
2072 nritems
* sizeof(struct btrfs_item
));
2074 copy_extent_buffer(right
, l
,
2075 btrfs_leaf_data(right
) + BTRFS_LEAF_DATA_SIZE(root
) -
2076 data_copy_size
, btrfs_leaf_data(l
) +
2077 leaf_data_end(root
, l
), data_copy_size
);
2079 rt_data_off
= BTRFS_LEAF_DATA_SIZE(root
) -
2080 btrfs_item_end_nr(l
, mid
);
2082 for (i
= 0; i
< nritems
; i
++) {
2083 struct btrfs_item
*item
= btrfs_item_nr(right
, i
);
2084 u32 ioff
= btrfs_item_offset(right
, item
);
2085 btrfs_set_item_offset(right
, item
, ioff
+ rt_data_off
);
2088 btrfs_set_header_nritems(l
, mid
);
2090 btrfs_item_key(right
, &disk_key
, 0);
2091 wret
= insert_ptr(trans
, root
, path
, &disk_key
, right
->start
,
2092 path
->slots
[1] + 1, 1);
2096 btrfs_mark_buffer_dirty(right
);
2097 btrfs_mark_buffer_dirty(l
);
2098 BUG_ON(path
->slots
[0] != slot
);
2100 ret
= btrfs_update_ref(trans
, root
, l
, right
, 0, nritems
);
2104 free_extent_buffer(path
->nodes
[0]);
2105 path
->nodes
[0] = right
;
2106 path
->slots
[0] -= mid
;
2107 path
->slots
[1] += 1;
2109 free_extent_buffer(right
);
2111 BUG_ON(path
->slots
[0] < 0);
2114 BUG_ON(num_doubles
!= 0);
2122 * This function splits a single item into two items,
2123 * giving 'new_key' to the new item and splitting the
2124 * old one at split_offset (from the start of the item).
2126 * The path may be released by this operation. After
2127 * the split, the path is pointing to the old item. The
2128 * new item is going to be in the same node as the old one.
2130 * Note, the item being split must be smaller enough to live alone on
2131 * a tree block with room for one extra struct btrfs_item
2133 * This allows us to split the item in place, keeping a lock on the
2134 * leaf the entire time.
2136 int btrfs_split_item(struct btrfs_trans_handle
*trans
,
2137 struct btrfs_root
*root
,
2138 struct btrfs_path
*path
,
2139 struct btrfs_key
*new_key
,
2140 unsigned long split_offset
)
2143 struct extent_buffer
*leaf
;
2144 struct btrfs_key orig_key
;
2145 struct btrfs_item
*item
;
2146 struct btrfs_item
*new_item
;
2151 struct btrfs_disk_key disk_key
;
2154 leaf
= path
->nodes
[0];
2155 btrfs_item_key_to_cpu(leaf
, &orig_key
, path
->slots
[0]);
2156 if (btrfs_leaf_free_space(root
, leaf
) >= sizeof(struct btrfs_item
))
2159 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
2160 btrfs_release_path(root
, path
);
2162 path
->search_for_split
= 1;
2164 ret
= btrfs_search_slot(trans
, root
, &orig_key
, path
, 0, 1);
2165 path
->search_for_split
= 0;
2167 /* if our item isn't there or got smaller, return now */
2168 if (ret
!= 0 || item_size
!= btrfs_item_size_nr(path
->nodes
[0],
2173 ret
= split_leaf(trans
, root
, &orig_key
, path
, 0, 0);
2176 BUG_ON(btrfs_leaf_free_space(root
, leaf
) < sizeof(struct btrfs_item
));
2177 leaf
= path
->nodes
[0];
2180 item
= btrfs_item_nr(leaf
, path
->slots
[0]);
2181 orig_offset
= btrfs_item_offset(leaf
, item
);
2182 item_size
= btrfs_item_size(leaf
, item
);
2185 buf
= kmalloc(item_size
, GFP_NOFS
);
2186 read_extent_buffer(leaf
, buf
, btrfs_item_ptr_offset(leaf
,
2187 path
->slots
[0]), item_size
);
2188 slot
= path
->slots
[0] + 1;
2189 leaf
= path
->nodes
[0];
2191 nritems
= btrfs_header_nritems(leaf
);
2193 if (slot
!= nritems
) {
2194 /* shift the items */
2195 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ 1),
2196 btrfs_item_nr_offset(slot
),
2197 (nritems
- slot
) * sizeof(struct btrfs_item
));
2201 btrfs_cpu_key_to_disk(&disk_key
, new_key
);
2202 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2204 new_item
= btrfs_item_nr(leaf
, slot
);
2206 btrfs_set_item_offset(leaf
, new_item
, orig_offset
);
2207 btrfs_set_item_size(leaf
, new_item
, item_size
- split_offset
);
2209 btrfs_set_item_offset(leaf
, item
,
2210 orig_offset
+ item_size
- split_offset
);
2211 btrfs_set_item_size(leaf
, item
, split_offset
);
2213 btrfs_set_header_nritems(leaf
, nritems
+ 1);
2215 /* write the data for the start of the original item */
2216 write_extent_buffer(leaf
, buf
,
2217 btrfs_item_ptr_offset(leaf
, path
->slots
[0]),
2220 /* write the data for the new item */
2221 write_extent_buffer(leaf
, buf
+ split_offset
,
2222 btrfs_item_ptr_offset(leaf
, slot
),
2223 item_size
- split_offset
);
2224 btrfs_mark_buffer_dirty(leaf
);
2227 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2228 btrfs_print_leaf(root
, leaf
);
2235 int btrfs_truncate_item(struct btrfs_trans_handle
*trans
,
2236 struct btrfs_root
*root
,
2237 struct btrfs_path
*path
,
2238 u32 new_size
, int from_end
)
2243 struct extent_buffer
*leaf
;
2244 struct btrfs_item
*item
;
2246 unsigned int data_end
;
2247 unsigned int old_data_start
;
2248 unsigned int old_size
;
2249 unsigned int size_diff
;
2252 slot_orig
= path
->slots
[0];
2253 leaf
= path
->nodes
[0];
2254 slot
= path
->slots
[0];
2256 old_size
= btrfs_item_size_nr(leaf
, slot
);
2257 if (old_size
== new_size
)
2260 nritems
= btrfs_header_nritems(leaf
);
2261 data_end
= leaf_data_end(root
, leaf
);
2263 old_data_start
= btrfs_item_offset_nr(leaf
, slot
);
2265 size_diff
= old_size
- new_size
;
2268 BUG_ON(slot
>= nritems
);
2271 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2273 /* first correct the data pointers */
2274 for (i
= slot
; i
< nritems
; i
++) {
2276 item
= btrfs_item_nr(leaf
, i
);
2277 ioff
= btrfs_item_offset(leaf
, item
);
2278 btrfs_set_item_offset(leaf
, item
, ioff
+ size_diff
);
2281 /* shift the data */
2283 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2284 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2285 data_end
, old_data_start
+ new_size
- data_end
);
2287 struct btrfs_disk_key disk_key
;
2290 btrfs_item_key(leaf
, &disk_key
, slot
);
2292 if (btrfs_disk_key_type(&disk_key
) == BTRFS_EXTENT_DATA_KEY
) {
2294 struct btrfs_file_extent_item
*fi
;
2296 fi
= btrfs_item_ptr(leaf
, slot
,
2297 struct btrfs_file_extent_item
);
2298 fi
= (struct btrfs_file_extent_item
*)(
2299 (unsigned long)fi
- size_diff
);
2301 if (btrfs_file_extent_type(leaf
, fi
) ==
2302 BTRFS_FILE_EXTENT_INLINE
) {
2303 ptr
= btrfs_item_ptr_offset(leaf
, slot
);
2304 memmove_extent_buffer(leaf
, ptr
,
2306 offsetof(struct btrfs_file_extent_item
,
2311 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2312 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2313 data_end
, old_data_start
- data_end
);
2315 offset
= btrfs_disk_key_offset(&disk_key
);
2316 btrfs_set_disk_key_offset(&disk_key
, offset
+ size_diff
);
2317 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2319 fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2322 item
= btrfs_item_nr(leaf
, slot
);
2323 btrfs_set_item_size(leaf
, item
, new_size
);
2324 btrfs_mark_buffer_dirty(leaf
);
2327 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2328 btrfs_print_leaf(root
, leaf
);
2334 int btrfs_extend_item(struct btrfs_trans_handle
*trans
,
2335 struct btrfs_root
*root
, struct btrfs_path
*path
,
2341 struct extent_buffer
*leaf
;
2342 struct btrfs_item
*item
;
2344 unsigned int data_end
;
2345 unsigned int old_data
;
2346 unsigned int old_size
;
2349 slot_orig
= path
->slots
[0];
2350 leaf
= path
->nodes
[0];
2352 nritems
= btrfs_header_nritems(leaf
);
2353 data_end
= leaf_data_end(root
, leaf
);
2355 if (btrfs_leaf_free_space(root
, leaf
) < data_size
) {
2356 btrfs_print_leaf(root
, leaf
);
2359 slot
= path
->slots
[0];
2360 old_data
= btrfs_item_end_nr(leaf
, slot
);
2363 if (slot
>= nritems
) {
2364 btrfs_print_leaf(root
, leaf
);
2365 printk("slot %d too large, nritems %d\n", slot
, nritems
);
2370 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2372 /* first correct the data pointers */
2373 for (i
= slot
; i
< nritems
; i
++) {
2375 item
= btrfs_item_nr(leaf
, i
);
2376 ioff
= btrfs_item_offset(leaf
, item
);
2377 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2380 /* shift the data */
2381 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2382 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2383 data_end
, old_data
- data_end
);
2385 data_end
= old_data
;
2386 old_size
= btrfs_item_size_nr(leaf
, slot
);
2387 item
= btrfs_item_nr(leaf
, slot
);
2388 btrfs_set_item_size(leaf
, item
, old_size
+ data_size
);
2389 btrfs_mark_buffer_dirty(leaf
);
2392 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2393 btrfs_print_leaf(root
, leaf
);
2400 * Given a key and some data, insert an item into the tree.
2401 * This does all the path init required, making room in the tree if needed.
2403 int btrfs_insert_empty_items(struct btrfs_trans_handle
*trans
,
2404 struct btrfs_root
*root
,
2405 struct btrfs_path
*path
,
2406 struct btrfs_key
*cpu_key
, u32
*data_size
,
2409 struct extent_buffer
*leaf
;
2410 struct btrfs_item
*item
;
2418 unsigned int data_end
;
2419 struct btrfs_disk_key disk_key
;
2421 for (i
= 0; i
< nr
; i
++) {
2422 total_data
+= data_size
[i
];
2425 /* create a root if there isn't one */
2429 total_size
= total_data
+ (nr
- 1) * sizeof(struct btrfs_item
);
2430 ret
= btrfs_search_slot(trans
, root
, cpu_key
, path
, total_size
, 1);
2437 slot_orig
= path
->slots
[0];
2438 leaf
= path
->nodes
[0];
2440 nritems
= btrfs_header_nritems(leaf
);
2441 data_end
= leaf_data_end(root
, leaf
);
2443 if (btrfs_leaf_free_space(root
, leaf
) <
2444 sizeof(struct btrfs_item
) + total_size
) {
2445 btrfs_print_leaf(root
, leaf
);
2446 printk("not enough freespace need %u have %d\n",
2447 total_size
, btrfs_leaf_free_space(root
, leaf
));
2451 slot
= path
->slots
[0];
2454 if (slot
!= nritems
) {
2456 unsigned int old_data
= btrfs_item_end_nr(leaf
, slot
);
2458 if (old_data
< data_end
) {
2459 btrfs_print_leaf(root
, leaf
);
2460 printk("slot %d old_data %d data_end %d\n",
2461 slot
, old_data
, data_end
);
2465 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2467 /* first correct the data pointers */
2468 for (i
= slot
; i
< nritems
; i
++) {
2471 item
= btrfs_item_nr(leaf
, i
);
2472 ioff
= btrfs_item_offset(leaf
, item
);
2473 btrfs_set_item_offset(leaf
, item
, ioff
- total_data
);
2476 /* shift the items */
2477 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ nr
),
2478 btrfs_item_nr_offset(slot
),
2479 (nritems
- slot
) * sizeof(struct btrfs_item
));
2481 /* shift the data */
2482 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2483 data_end
- total_data
, btrfs_leaf_data(leaf
) +
2484 data_end
, old_data
- data_end
);
2485 data_end
= old_data
;
2488 /* setup the item for the new data */
2489 for (i
= 0; i
< nr
; i
++) {
2490 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
+ i
);
2491 btrfs_set_item_key(leaf
, &disk_key
, slot
+ i
);
2492 item
= btrfs_item_nr(leaf
, slot
+ i
);
2493 btrfs_set_item_offset(leaf
, item
, data_end
- data_size
[i
]);
2494 data_end
-= data_size
[i
];
2495 btrfs_set_item_size(leaf
, item
, data_size
[i
]);
2497 btrfs_set_header_nritems(leaf
, nritems
+ nr
);
2498 btrfs_mark_buffer_dirty(leaf
);
2502 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
);
2503 ret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2506 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2507 btrfs_print_leaf(root
, leaf
);
2516 * Given a key and some data, insert an item into the tree.
2517 * This does all the path init required, making room in the tree if needed.
2519 int btrfs_insert_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
2520 *root
, struct btrfs_key
*cpu_key
, void *data
, u32
2524 struct btrfs_path
*path
;
2525 struct extent_buffer
*leaf
;
2528 path
= btrfs_alloc_path();
2530 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
2532 leaf
= path
->nodes
[0];
2533 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2534 write_extent_buffer(leaf
, data
, ptr
, data_size
);
2535 btrfs_mark_buffer_dirty(leaf
);
2537 btrfs_free_path(path
);
2542 * delete the pointer from a given node.
2544 * If the delete empties a node, the node is removed from the tree,
2545 * continuing all the way the root if required. The root is converted into
2546 * a leaf if all the nodes are emptied.
2548 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2549 struct btrfs_path
*path
, int level
, int slot
)
2551 struct extent_buffer
*parent
= path
->nodes
[level
];
2556 nritems
= btrfs_header_nritems(parent
);
2557 if (slot
!= nritems
-1) {
2558 memmove_extent_buffer(parent
,
2559 btrfs_node_key_ptr_offset(slot
),
2560 btrfs_node_key_ptr_offset(slot
+ 1),
2561 sizeof(struct btrfs_key_ptr
) *
2562 (nritems
- slot
- 1));
2565 btrfs_set_header_nritems(parent
, nritems
);
2566 if (nritems
== 0 && parent
== root
->node
) {
2567 BUG_ON(btrfs_header_level(root
->node
) != 1);
2568 /* just turn the root into a leaf and break */
2569 btrfs_set_header_level(root
->node
, 0);
2570 } else if (slot
== 0) {
2571 struct btrfs_disk_key disk_key
;
2573 btrfs_node_key(parent
, &disk_key
, 0);
2574 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, level
+ 1);
2578 btrfs_mark_buffer_dirty(parent
);
2583 * delete the item at the leaf level in path. If that empties
2584 * the leaf, remove it from the tree
2586 int btrfs_del_items(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2587 struct btrfs_path
*path
, int slot
, int nr
)
2589 struct extent_buffer
*leaf
;
2590 struct btrfs_item
*item
;
2598 leaf
= path
->nodes
[0];
2599 last_off
= btrfs_item_offset_nr(leaf
, slot
+ nr
- 1);
2601 for (i
= 0; i
< nr
; i
++)
2602 dsize
+= btrfs_item_size_nr(leaf
, slot
+ i
);
2604 nritems
= btrfs_header_nritems(leaf
);
2606 if (slot
+ nr
!= nritems
) {
2608 int data_end
= leaf_data_end(root
, leaf
);
2610 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2612 btrfs_leaf_data(leaf
) + data_end
,
2613 last_off
- data_end
);
2615 for (i
= slot
+ nr
; i
< nritems
; i
++) {
2618 item
= btrfs_item_nr(leaf
, i
);
2619 ioff
= btrfs_item_offset(leaf
, item
);
2620 btrfs_set_item_offset(leaf
, item
, ioff
+ dsize
);
2623 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
),
2624 btrfs_item_nr_offset(slot
+ nr
),
2625 sizeof(struct btrfs_item
) *
2626 (nritems
- slot
- nr
));
2628 btrfs_set_header_nritems(leaf
, nritems
- nr
);
2631 /* delete the leaf if we've emptied it */
2633 if (leaf
== root
->node
) {
2634 btrfs_set_header_level(leaf
, 0);
2636 u64 root_gen
= btrfs_header_generation(path
->nodes
[1]);
2637 clean_tree_block(trans
, root
, leaf
);
2638 wait_on_tree_block_writeback(root
, leaf
);
2639 wret
= del_ptr(trans
, root
, path
, 1, path
->slots
[1]);
2642 wret
= btrfs_free_extent(trans
, root
,
2643 leaf
->start
, leaf
->len
,
2644 path
->nodes
[1]->start
,
2645 btrfs_header_owner(path
->nodes
[1]),
2651 int used
= leaf_space_used(leaf
, 0, nritems
);
2653 struct btrfs_disk_key disk_key
;
2655 btrfs_item_key(leaf
, &disk_key
, 0);
2656 wret
= fixup_low_keys(trans
, root
, path
,
2662 /* delete the leaf if it is mostly empty */
2663 if (used
< BTRFS_LEAF_DATA_SIZE(root
) / 4) {
2664 /* push_leaf_left fixes the path.
2665 * make sure the path still points to our leaf
2666 * for possible call to del_ptr below
2668 slot
= path
->slots
[1];
2669 extent_buffer_get(leaf
);
2671 wret
= push_leaf_left(trans
, root
, path
, 1, 1);
2672 if (wret
< 0 && wret
!= -ENOSPC
)
2675 if (path
->nodes
[0] == leaf
&&
2676 btrfs_header_nritems(leaf
)) {
2677 wret
= push_leaf_right(trans
, root
, path
, 1, 1);
2678 if (wret
< 0 && wret
!= -ENOSPC
)
2682 if (btrfs_header_nritems(leaf
) == 0) {
2684 u64 bytenr
= leaf
->start
;
2685 u32 blocksize
= leaf
->len
;
2687 root_gen
= btrfs_header_generation(
2690 clean_tree_block(trans
, root
, leaf
);
2691 wait_on_tree_block_writeback(root
, leaf
);
2693 wret
= del_ptr(trans
, root
, path
, 1, slot
);
2697 free_extent_buffer(leaf
);
2698 wret
= btrfs_free_extent(trans
, root
, bytenr
,
2699 blocksize
, path
->nodes
[1]->start
,
2700 btrfs_header_owner(path
->nodes
[1]),
2705 btrfs_mark_buffer_dirty(leaf
);
2706 free_extent_buffer(leaf
);
2709 btrfs_mark_buffer_dirty(leaf
);
2716 * walk up the tree as far as required to find the previous leaf.
2717 * returns 0 if it found something or 1 if there are no lesser leaves.
2718 * returns < 0 on io errors.
2720 int btrfs_prev_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2724 struct extent_buffer
*c
;
2725 struct extent_buffer
*next
= NULL
;
2727 while(level
< BTRFS_MAX_LEVEL
) {
2728 if (!path
->nodes
[level
])
2731 slot
= path
->slots
[level
];
2732 c
= path
->nodes
[level
];
2735 if (level
== BTRFS_MAX_LEVEL
)
2742 free_extent_buffer(next
);
2744 next
= read_node_slot(root
, c
, slot
);
2747 path
->slots
[level
] = slot
;
2750 c
= path
->nodes
[level
];
2751 free_extent_buffer(c
);
2752 slot
= btrfs_header_nritems(next
);
2755 path
->nodes
[level
] = next
;
2756 path
->slots
[level
] = slot
;
2759 next
= read_node_slot(root
, next
, slot
);
2765 * walk up the tree as far as required to find the next leaf.
2766 * returns 0 if it found something or 1 if there are no greater leaves.
2767 * returns < 0 on io errors.
2769 int btrfs_next_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2773 struct extent_buffer
*c
;
2774 struct extent_buffer
*next
= NULL
;
2776 while(level
< BTRFS_MAX_LEVEL
) {
2777 if (!path
->nodes
[level
])
2780 slot
= path
->slots
[level
] + 1;
2781 c
= path
->nodes
[level
];
2782 if (slot
>= btrfs_header_nritems(c
)) {
2784 if (level
== BTRFS_MAX_LEVEL
)
2790 free_extent_buffer(next
);
2793 reada_for_search(root
, path
, level
, slot
, 0);
2795 next
= read_node_slot(root
, c
, slot
);
2798 path
->slots
[level
] = slot
;
2801 c
= path
->nodes
[level
];
2802 free_extent_buffer(c
);
2803 path
->nodes
[level
] = next
;
2804 path
->slots
[level
] = 0;
2808 reada_for_search(root
, path
, level
, 0, 0);
2809 next
= read_node_slot(root
, next
, 0);
2814 int btrfs_previous_item(struct btrfs_root
*root
,
2815 struct btrfs_path
*path
, u64 min_objectid
,
2818 struct btrfs_key found_key
;
2819 struct extent_buffer
*leaf
;
2823 if (path
->slots
[0] == 0) {
2824 ret
= btrfs_prev_leaf(root
, path
);
2830 leaf
= path
->nodes
[0];
2831 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
2832 if (found_key
.type
== type
)