2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/sched.h>
22 #include "transaction.h"
23 #include "print-tree.h"
25 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
26 *root
, struct btrfs_path
*path
, int level
);
27 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
28 *root
, struct btrfs_key
*ins_key
,
29 struct btrfs_path
*path
, int data_size
, int extend
);
30 static int push_node_left(struct btrfs_trans_handle
*trans
,
31 struct btrfs_root
*root
, struct extent_buffer
*dst
,
32 struct extent_buffer
*src
);
33 static int balance_node_right(struct btrfs_trans_handle
*trans
,
34 struct btrfs_root
*root
,
35 struct extent_buffer
*dst_buf
,
36 struct extent_buffer
*src_buf
);
37 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
38 struct btrfs_path
*path
, int level
, int slot
);
40 inline void btrfs_init_path(struct btrfs_path
*p
)
42 memset(p
, 0, sizeof(*p
));
45 struct btrfs_path
*btrfs_alloc_path(void)
47 struct btrfs_path
*path
;
48 path
= kmem_cache_alloc(btrfs_path_cachep
, GFP_NOFS
);
50 btrfs_init_path(path
);
56 void btrfs_free_path(struct btrfs_path
*p
)
58 btrfs_release_path(NULL
, p
);
59 kmem_cache_free(btrfs_path_cachep
, p
);
62 void btrfs_release_path(struct btrfs_root
*root
, struct btrfs_path
*p
)
65 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++) {
68 free_extent_buffer(p
->nodes
[i
]);
70 memset(p
, 0, sizeof(*p
));
73 static void add_root_to_dirty_list(struct btrfs_root
*root
)
75 if (root
->track_dirty
&& list_empty(&root
->dirty_list
)) {
76 list_add(&root
->dirty_list
,
77 &root
->fs_info
->dirty_cowonly_roots
);
81 int btrfs_copy_root(struct btrfs_trans_handle
*trans
,
82 struct btrfs_root
*root
,
83 struct extent_buffer
*buf
,
84 struct extent_buffer
**cow_ret
, u64 new_root_objectid
)
86 struct extent_buffer
*cow
;
90 struct btrfs_key first_key
;
91 struct btrfs_root
*new_root
;
93 new_root
= kmalloc(sizeof(*new_root
), GFP_NOFS
);
97 memcpy(new_root
, root
, sizeof(*new_root
));
98 new_root
->root_key
.objectid
= new_root_objectid
;
100 WARN_ON(root
->ref_cows
&& trans
->transid
!=
101 root
->fs_info
->running_transaction
->transid
);
102 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
104 level
= btrfs_header_level(buf
);
105 nritems
= btrfs_header_nritems(buf
);
108 btrfs_item_key_to_cpu(buf
, &first_key
, 0);
110 btrfs_node_key_to_cpu(buf
, &first_key
, 0);
112 first_key
.objectid
= 0;
114 cow
= __btrfs_alloc_free_block(trans
, new_root
, buf
->len
,
116 trans
->transid
, first_key
.objectid
,
117 level
, buf
->start
, 0);
123 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
124 btrfs_set_header_bytenr(cow
, cow
->start
);
125 btrfs_set_header_generation(cow
, trans
->transid
);
126 btrfs_set_header_owner(cow
, new_root_objectid
);
127 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
129 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
130 ret
= btrfs_inc_ref(trans
, new_root
, buf
);
136 btrfs_mark_buffer_dirty(cow
);
141 int __btrfs_cow_block(struct btrfs_trans_handle
*trans
,
142 struct btrfs_root
*root
,
143 struct extent_buffer
*buf
,
144 struct extent_buffer
*parent
, int parent_slot
,
145 struct extent_buffer
**cow_ret
,
146 u64 search_start
, u64 empty_size
)
149 struct extent_buffer
*cow
;
152 int different_trans
= 0;
154 struct btrfs_key first_key
;
156 if (root
->ref_cows
) {
157 root_gen
= trans
->transid
;
162 WARN_ON(root
->ref_cows
&& trans
->transid
!=
163 root
->fs_info
->running_transaction
->transid
);
164 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
166 level
= btrfs_header_level(buf
);
167 nritems
= btrfs_header_nritems(buf
);
170 btrfs_item_key_to_cpu(buf
, &first_key
, 0);
172 btrfs_node_key_to_cpu(buf
, &first_key
, 0);
174 first_key
.objectid
= 0;
176 cow
= __btrfs_alloc_free_block(trans
, root
, buf
->len
,
177 root
->root_key
.objectid
,
178 root_gen
, first_key
.objectid
, level
,
179 search_start
, empty_size
);
183 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
184 btrfs_set_header_bytenr(cow
, cow
->start
);
185 btrfs_set_header_generation(cow
, trans
->transid
);
186 btrfs_set_header_owner(cow
, root
->root_key
.objectid
);
187 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
189 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
190 if (btrfs_header_generation(buf
) != trans
->transid
) {
192 ret
= btrfs_inc_ref(trans
, root
, buf
);
196 clean_tree_block(trans
, root
, buf
);
199 if (buf
== root
->node
) {
200 root_gen
= btrfs_header_generation(buf
);
202 extent_buffer_get(cow
);
203 if (buf
!= root
->commit_root
) {
204 btrfs_free_extent(trans
, root
, buf
->start
,
205 buf
->len
, root
->root_key
.objectid
,
208 free_extent_buffer(buf
);
209 add_root_to_dirty_list(root
);
211 root_gen
= btrfs_header_generation(parent
);
212 btrfs_set_node_blockptr(parent
, parent_slot
,
214 WARN_ON(trans
->transid
== 0);
215 btrfs_set_node_ptr_generation(parent
, parent_slot
,
217 btrfs_mark_buffer_dirty(parent
);
218 WARN_ON(btrfs_header_generation(parent
) != trans
->transid
);
219 btrfs_free_extent(trans
, root
, buf
->start
, buf
->len
,
220 btrfs_header_owner(parent
), root_gen
,
223 free_extent_buffer(buf
);
224 btrfs_mark_buffer_dirty(cow
);
229 int btrfs_cow_block(struct btrfs_trans_handle
*trans
,
230 struct btrfs_root
*root
, struct extent_buffer
*buf
,
231 struct extent_buffer
*parent
, int parent_slot
,
232 struct extent_buffer
**cow_ret
)
238 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
239 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
240 root
->fs_info
->running_transaction
->transid
);
243 if (trans
->transid
!= root
->fs_info
->generation
) {
244 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
245 root
->fs_info
->generation
);
249 header_trans
= btrfs_header_generation(buf
);
250 spin_lock(&root
->fs_info
->hash_lock
);
251 if (header_trans
== trans
->transid
&&
252 !btrfs_header_flag(buf
, BTRFS_HEADER_FLAG_WRITTEN
)) {
254 spin_unlock(&root
->fs_info
->hash_lock
);
257 spin_unlock(&root
->fs_info
->hash_lock
);
258 search_start
= buf
->start
& ~((u64
)(1024 * 1024 * 1024) - 1);
259 ret
= __btrfs_cow_block(trans
, root
, buf
, parent
,
260 parent_slot
, cow_ret
, search_start
, 0);
264 static int close_blocks(u64 blocknr
, u64 other
, u32 blocksize
)
266 if (blocknr
< other
&& other
- (blocknr
+ blocksize
) < 32768)
268 if (blocknr
> other
&& blocknr
- (other
+ blocksize
) < 32768)
274 * compare two keys in a memcmp fashion
276 static int comp_keys(struct btrfs_disk_key
*disk
, struct btrfs_key
*k2
)
280 btrfs_disk_key_to_cpu(&k1
, disk
);
282 if (k1
.objectid
> k2
->objectid
)
284 if (k1
.objectid
< k2
->objectid
)
286 if (k1
.type
> k2
->type
)
288 if (k1
.type
< k2
->type
)
290 if (k1
.offset
> k2
->offset
)
292 if (k1
.offset
< k2
->offset
)
298 int btrfs_realloc_node(struct btrfs_trans_handle
*trans
,
299 struct btrfs_root
*root
, struct extent_buffer
*parent
,
300 int start_slot
, int cache_only
, u64
*last_ret
,
301 struct btrfs_key
*progress
)
303 struct extent_buffer
*cur
;
304 struct extent_buffer
*tmp
;
306 u64 search_start
= *last_ret
;
316 int progress_passed
= 0;
317 struct btrfs_disk_key disk_key
;
319 parent_level
= btrfs_header_level(parent
);
320 if (cache_only
&& parent_level
!= 1)
323 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
324 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
325 root
->fs_info
->running_transaction
->transid
);
328 if (trans
->transid
!= root
->fs_info
->generation
) {
329 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
330 root
->fs_info
->generation
);
334 parent_nritems
= btrfs_header_nritems(parent
);
335 blocksize
= btrfs_level_size(root
, parent_level
- 1);
336 end_slot
= parent_nritems
;
338 if (parent_nritems
== 1)
341 for (i
= start_slot
; i
< end_slot
; i
++) {
344 if (!parent
->map_token
) {
345 map_extent_buffer(parent
,
346 btrfs_node_key_ptr_offset(i
),
347 sizeof(struct btrfs_key_ptr
),
348 &parent
->map_token
, &parent
->kaddr
,
349 &parent
->map_start
, &parent
->map_len
,
352 btrfs_node_key(parent
, &disk_key
, i
);
353 if (!progress_passed
&& comp_keys(&disk_key
, progress
) < 0)
357 blocknr
= btrfs_node_blockptr(parent
, i
);
359 last_block
= blocknr
;
362 other
= btrfs_node_blockptr(parent
, i
- 1);
363 close
= close_blocks(blocknr
, other
, blocksize
);
365 if (close
&& i
< end_slot
- 2) {
366 other
= btrfs_node_blockptr(parent
, i
+ 1);
367 close
= close_blocks(blocknr
, other
, blocksize
);
370 last_block
= blocknr
;
373 if (parent
->map_token
) {
374 unmap_extent_buffer(parent
, parent
->map_token
,
376 parent
->map_token
= NULL
;
379 cur
= btrfs_find_tree_block(root
, blocknr
, blocksize
);
381 uptodate
= btrfs_buffer_uptodate(cur
);
384 if (!cur
|| !uptodate
) {
386 free_extent_buffer(cur
);
390 cur
= read_tree_block(root
, blocknr
,
392 } else if (!uptodate
) {
393 btrfs_read_buffer(cur
);
396 if (search_start
== 0)
397 search_start
= last_block
;
399 err
= __btrfs_cow_block(trans
, root
, cur
, parent
, i
,
402 (end_slot
- i
) * blocksize
));
404 free_extent_buffer(cur
);
407 search_start
= tmp
->start
;
408 last_block
= tmp
->start
;
409 *last_ret
= search_start
;
410 if (parent_level
== 1)
411 btrfs_clear_buffer_defrag(tmp
);
412 free_extent_buffer(tmp
);
414 if (parent
->map_token
) {
415 unmap_extent_buffer(parent
, parent
->map_token
,
417 parent
->map_token
= NULL
;
423 * The leaf data grows from end-to-front in the node.
424 * this returns the address of the start of the last item,
425 * which is the stop of the leaf data stack
427 static inline unsigned int leaf_data_end(struct btrfs_root
*root
,
428 struct extent_buffer
*leaf
)
430 u32 nr
= btrfs_header_nritems(leaf
);
432 return BTRFS_LEAF_DATA_SIZE(root
);
433 return btrfs_item_offset_nr(leaf
, nr
- 1);
436 static int check_node(struct btrfs_root
*root
, struct btrfs_path
*path
,
439 struct extent_buffer
*parent
= NULL
;
440 struct extent_buffer
*node
= path
->nodes
[level
];
441 struct btrfs_disk_key parent_key
;
442 struct btrfs_disk_key node_key
;
445 struct btrfs_key cpukey
;
446 u32 nritems
= btrfs_header_nritems(node
);
448 if (path
->nodes
[level
+ 1])
449 parent
= path
->nodes
[level
+ 1];
451 slot
= path
->slots
[level
];
452 BUG_ON(nritems
== 0);
454 parent_slot
= path
->slots
[level
+ 1];
455 btrfs_node_key(parent
, &parent_key
, parent_slot
);
456 btrfs_node_key(node
, &node_key
, 0);
457 BUG_ON(memcmp(&parent_key
, &node_key
,
458 sizeof(struct btrfs_disk_key
)));
459 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
460 btrfs_header_bytenr(node
));
462 BUG_ON(nritems
> BTRFS_NODEPTRS_PER_BLOCK(root
));
464 btrfs_node_key_to_cpu(node
, &cpukey
, slot
- 1);
465 btrfs_node_key(node
, &node_key
, slot
);
466 BUG_ON(comp_keys(&node_key
, &cpukey
) <= 0);
468 if (slot
< nritems
- 1) {
469 btrfs_node_key_to_cpu(node
, &cpukey
, slot
+ 1);
470 btrfs_node_key(node
, &node_key
, slot
);
471 BUG_ON(comp_keys(&node_key
, &cpukey
) >= 0);
476 static int check_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
,
479 struct extent_buffer
*leaf
= path
->nodes
[level
];
480 struct extent_buffer
*parent
= NULL
;
482 struct btrfs_key cpukey
;
483 struct btrfs_disk_key parent_key
;
484 struct btrfs_disk_key leaf_key
;
485 int slot
= path
->slots
[0];
487 u32 nritems
= btrfs_header_nritems(leaf
);
489 if (path
->nodes
[level
+ 1])
490 parent
= path
->nodes
[level
+ 1];
496 parent_slot
= path
->slots
[level
+ 1];
497 btrfs_node_key(parent
, &parent_key
, parent_slot
);
498 btrfs_item_key(leaf
, &leaf_key
, 0);
500 BUG_ON(memcmp(&parent_key
, &leaf_key
,
501 sizeof(struct btrfs_disk_key
)));
502 BUG_ON(btrfs_node_blockptr(parent
, parent_slot
) !=
503 btrfs_header_bytenr(leaf
));
506 for (i
= 0; nritems
> 1 && i
< nritems
- 2; i
++) {
507 btrfs_item_key_to_cpu(leaf
, &cpukey
, i
+ 1);
508 btrfs_item_key(leaf
, &leaf_key
, i
);
509 if (comp_keys(&leaf_key
, &cpukey
) >= 0) {
510 btrfs_print_leaf(root
, leaf
);
511 printk("slot %d offset bad key\n", i
);
514 if (btrfs_item_offset_nr(leaf
, i
) !=
515 btrfs_item_end_nr(leaf
, i
+ 1)) {
516 btrfs_print_leaf(root
, leaf
);
517 printk("slot %d offset bad\n", i
);
521 if (btrfs_item_offset_nr(leaf
, i
) +
522 btrfs_item_size_nr(leaf
, i
) !=
523 BTRFS_LEAF_DATA_SIZE(root
)) {
524 btrfs_print_leaf(root
, leaf
);
525 printk("slot %d first offset bad\n", i
);
531 if (btrfs_item_size_nr(leaf
, nritems
- 1) > 4096) {
532 btrfs_print_leaf(root
, leaf
);
533 printk("slot %d bad size \n", nritems
- 1);
538 if (slot
!= 0 && slot
< nritems
- 1) {
539 btrfs_item_key(leaf
, &leaf_key
, slot
);
540 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
- 1);
541 if (comp_keys(&leaf_key
, &cpukey
) <= 0) {
542 btrfs_print_leaf(root
, leaf
);
543 printk("slot %d offset bad key\n", slot
);
546 if (btrfs_item_offset_nr(leaf
, slot
- 1) !=
547 btrfs_item_end_nr(leaf
, slot
)) {
548 btrfs_print_leaf(root
, leaf
);
549 printk("slot %d offset bad\n", slot
);
553 if (slot
< nritems
- 1) {
554 btrfs_item_key(leaf
, &leaf_key
, slot
);
555 btrfs_item_key_to_cpu(leaf
, &cpukey
, slot
+ 1);
556 BUG_ON(comp_keys(&leaf_key
, &cpukey
) >= 0);
557 if (btrfs_item_offset_nr(leaf
, slot
) !=
558 btrfs_item_end_nr(leaf
, slot
+ 1)) {
559 btrfs_print_leaf(root
, leaf
);
560 printk("slot %d offset bad\n", slot
);
564 BUG_ON(btrfs_item_offset_nr(leaf
, 0) +
565 btrfs_item_size_nr(leaf
, 0) != BTRFS_LEAF_DATA_SIZE(root
));
569 static int noinline
check_block(struct btrfs_root
*root
,
570 struct btrfs_path
*path
, int level
)
574 struct extent_buffer
*buf
= path
->nodes
[level
];
576 if (memcmp_extent_buffer(buf
, root
->fs_info
->fsid
,
577 (unsigned long)btrfs_header_fsid(buf
),
579 printk("warning bad block %Lu\n", buf
->start
);
584 return check_leaf(root
, path
, level
);
585 return check_node(root
, path
, level
);
589 * search for key in the extent_buffer. The items start at offset p,
590 * and they are item_size apart. There are 'max' items in p.
592 * the slot in the array is returned via slot, and it points to
593 * the place where you would insert key if it is not found in
596 * slot may point to max if the key is bigger than all of the keys
598 static int generic_bin_search(struct extent_buffer
*eb
, unsigned long p
,
599 int item_size
, struct btrfs_key
*key
,
606 struct btrfs_disk_key
*tmp
= NULL
;
607 struct btrfs_disk_key unaligned
;
608 unsigned long offset
;
609 char *map_token
= NULL
;
611 unsigned long map_start
= 0;
612 unsigned long map_len
= 0;
616 mid
= (low
+ high
) / 2;
617 offset
= p
+ mid
* item_size
;
619 if (!map_token
|| offset
< map_start
||
620 (offset
+ sizeof(struct btrfs_disk_key
)) >
621 map_start
+ map_len
) {
623 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
626 err
= map_extent_buffer(eb
, offset
,
627 sizeof(struct btrfs_disk_key
),
629 &map_start
, &map_len
, KM_USER0
);
632 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
635 read_extent_buffer(eb
, &unaligned
,
636 offset
, sizeof(unaligned
));
641 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
644 ret
= comp_keys(tmp
, key
);
653 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
659 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
664 * simple bin_search frontend that does the right thing for
667 static int bin_search(struct extent_buffer
*eb
, struct btrfs_key
*key
,
668 int level
, int *slot
)
671 return generic_bin_search(eb
,
672 offsetof(struct btrfs_leaf
, items
),
673 sizeof(struct btrfs_item
),
674 key
, btrfs_header_nritems(eb
),
677 return generic_bin_search(eb
,
678 offsetof(struct btrfs_node
, ptrs
),
679 sizeof(struct btrfs_key_ptr
),
680 key
, btrfs_header_nritems(eb
),
686 static struct extent_buffer
*read_node_slot(struct btrfs_root
*root
,
687 struct extent_buffer
*parent
, int slot
)
691 if (slot
>= btrfs_header_nritems(parent
))
693 return read_tree_block(root
, btrfs_node_blockptr(parent
, slot
),
694 btrfs_level_size(root
, btrfs_header_level(parent
) - 1));
697 static int balance_level(struct btrfs_trans_handle
*trans
,
698 struct btrfs_root
*root
,
699 struct btrfs_path
*path
, int level
)
701 struct extent_buffer
*right
= NULL
;
702 struct extent_buffer
*mid
;
703 struct extent_buffer
*left
= NULL
;
704 struct extent_buffer
*parent
= NULL
;
708 int orig_slot
= path
->slots
[level
];
709 int err_on_enospc
= 0;
715 mid
= path
->nodes
[level
];
716 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
718 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
720 if (level
< BTRFS_MAX_LEVEL
- 1)
721 parent
= path
->nodes
[level
+ 1];
722 pslot
= path
->slots
[level
+ 1];
725 * deal with the case where there is only one pointer in the root
726 * by promoting the node below to a root
729 struct extent_buffer
*child
;
731 if (btrfs_header_nritems(mid
) != 1)
734 /* promote the child to a root */
735 child
= read_node_slot(root
, mid
, 0);
737 ret
= btrfs_cow_block(trans
, root
, child
, mid
, 0, &child
);
741 add_root_to_dirty_list(root
);
742 path
->nodes
[level
] = NULL
;
743 clean_tree_block(trans
, root
, mid
);
744 wait_on_tree_block_writeback(root
, mid
);
745 /* once for the path */
746 free_extent_buffer(mid
);
747 ret
= btrfs_free_extent(trans
, root
, mid
->start
, mid
->len
,
748 root
->root_key
.objectid
,
749 btrfs_header_generation(mid
), 0, 0, 1);
750 /* once for the root ptr */
751 free_extent_buffer(mid
);
754 if (btrfs_header_nritems(mid
) >
755 BTRFS_NODEPTRS_PER_BLOCK(root
) / 4)
758 if (btrfs_header_nritems(mid
) < 2)
761 left
= read_node_slot(root
, parent
, pslot
- 1);
763 wret
= btrfs_cow_block(trans
, root
, left
,
764 parent
, pslot
- 1, &left
);
770 right
= read_node_slot(root
, parent
, pslot
+ 1);
772 wret
= btrfs_cow_block(trans
, root
, right
,
773 parent
, pslot
+ 1, &right
);
780 /* first, try to make some room in the middle buffer */
782 orig_slot
+= btrfs_header_nritems(left
);
783 wret
= push_node_left(trans
, root
, left
, mid
);
786 if (btrfs_header_nritems(mid
) < 2)
791 * then try to empty the right most buffer into the middle
794 wret
= push_node_left(trans
, root
, mid
, right
);
795 if (wret
< 0 && wret
!= -ENOSPC
)
797 if (btrfs_header_nritems(right
) == 0) {
798 u64 bytenr
= right
->start
;
799 u64 generation
= btrfs_header_generation(parent
);
800 u32 blocksize
= right
->len
;
802 clean_tree_block(trans
, root
, right
);
803 wait_on_tree_block_writeback(root
, right
);
804 free_extent_buffer(right
);
806 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
+
810 wret
= btrfs_free_extent(trans
, root
, bytenr
,
812 btrfs_header_owner(parent
),
813 generation
, 0, 0, 1);
817 struct btrfs_disk_key right_key
;
818 btrfs_node_key(right
, &right_key
, 0);
819 btrfs_set_node_key(parent
, &right_key
, pslot
+ 1);
820 btrfs_mark_buffer_dirty(parent
);
823 if (btrfs_header_nritems(mid
) == 1) {
825 * we're not allowed to leave a node with one item in the
826 * tree during a delete. A deletion from lower in the tree
827 * could try to delete the only pointer in this node.
828 * So, pull some keys from the left.
829 * There has to be a left pointer at this point because
830 * otherwise we would have pulled some pointers from the
834 wret
= balance_node_right(trans
, root
, mid
, left
);
841 if (btrfs_header_nritems(mid
) == 0) {
842 /* we've managed to empty the middle node, drop it */
843 u64 root_gen
= btrfs_header_generation(parent
);
844 u64 bytenr
= mid
->start
;
845 u32 blocksize
= mid
->len
;
846 clean_tree_block(trans
, root
, mid
);
847 wait_on_tree_block_writeback(root
, mid
);
848 free_extent_buffer(mid
);
850 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
);
853 wret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
,
854 btrfs_header_owner(parent
),
859 /* update the parent key to reflect our changes */
860 struct btrfs_disk_key mid_key
;
861 btrfs_node_key(mid
, &mid_key
, 0);
862 btrfs_set_node_key(parent
, &mid_key
, pslot
);
863 btrfs_mark_buffer_dirty(parent
);
866 /* update the path */
868 if (btrfs_header_nritems(left
) > orig_slot
) {
869 extent_buffer_get(left
);
870 path
->nodes
[level
] = left
;
871 path
->slots
[level
+ 1] -= 1;
872 path
->slots
[level
] = orig_slot
;
874 free_extent_buffer(mid
);
876 orig_slot
-= btrfs_header_nritems(left
);
877 path
->slots
[level
] = orig_slot
;
880 /* double check we haven't messed things up */
881 check_block(root
, path
, level
);
883 btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]))
887 free_extent_buffer(right
);
889 free_extent_buffer(left
);
893 /* returns zero if the push worked, non-zero otherwise */
894 static int noinline
push_nodes_for_insert(struct btrfs_trans_handle
*trans
,
895 struct btrfs_root
*root
,
896 struct btrfs_path
*path
, int level
)
898 struct extent_buffer
*right
= NULL
;
899 struct extent_buffer
*mid
;
900 struct extent_buffer
*left
= NULL
;
901 struct extent_buffer
*parent
= NULL
;
905 int orig_slot
= path
->slots
[level
];
911 mid
= path
->nodes
[level
];
912 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
913 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
915 if (level
< BTRFS_MAX_LEVEL
- 1)
916 parent
= path
->nodes
[level
+ 1];
917 pslot
= path
->slots
[level
+ 1];
922 left
= read_node_slot(root
, parent
, pslot
- 1);
924 /* first, try to make some room in the middle buffer */
927 left_nr
= btrfs_header_nritems(left
);
928 if (left_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
931 ret
= btrfs_cow_block(trans
, root
, left
, parent
,
936 wret
= push_node_left(trans
, root
,
943 struct btrfs_disk_key disk_key
;
944 orig_slot
+= left_nr
;
945 btrfs_node_key(mid
, &disk_key
, 0);
946 btrfs_set_node_key(parent
, &disk_key
, pslot
);
947 btrfs_mark_buffer_dirty(parent
);
948 if (btrfs_header_nritems(left
) > orig_slot
) {
949 path
->nodes
[level
] = left
;
950 path
->slots
[level
+ 1] -= 1;
951 path
->slots
[level
] = orig_slot
;
952 free_extent_buffer(mid
);
955 btrfs_header_nritems(left
);
956 path
->slots
[level
] = orig_slot
;
957 free_extent_buffer(left
);
961 free_extent_buffer(left
);
963 right
= read_node_slot(root
, parent
, pslot
+ 1);
966 * then try to empty the right most buffer into the middle
970 right_nr
= btrfs_header_nritems(right
);
971 if (right_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
974 ret
= btrfs_cow_block(trans
, root
, right
,
980 wret
= balance_node_right(trans
, root
,
987 struct btrfs_disk_key disk_key
;
989 btrfs_node_key(right
, &disk_key
, 0);
990 btrfs_set_node_key(parent
, &disk_key
, pslot
+ 1);
991 btrfs_mark_buffer_dirty(parent
);
993 if (btrfs_header_nritems(mid
) <= orig_slot
) {
994 path
->nodes
[level
] = right
;
995 path
->slots
[level
+ 1] += 1;
996 path
->slots
[level
] = orig_slot
-
997 btrfs_header_nritems(mid
);
998 free_extent_buffer(mid
);
1000 free_extent_buffer(right
);
1004 free_extent_buffer(right
);
1010 * readahead one full node of leaves
1012 static void reada_for_search(struct btrfs_root
*root
, struct btrfs_path
*path
,
1013 int level
, int slot
, u64 objectid
)
1015 struct extent_buffer
*node
;
1016 struct btrfs_disk_key disk_key
;
1022 int direction
= path
->reada
;
1023 struct extent_buffer
*eb
;
1031 if (!path
->nodes
[level
])
1034 node
= path
->nodes
[level
];
1035 search
= btrfs_node_blockptr(node
, slot
);
1036 blocksize
= btrfs_level_size(root
, level
- 1);
1037 eb
= btrfs_find_tree_block(root
, search
, blocksize
);
1039 free_extent_buffer(eb
);
1043 highest_read
= search
;
1044 lowest_read
= search
;
1046 nritems
= btrfs_header_nritems(node
);
1049 if (direction
< 0) {
1053 } else if (direction
> 0) {
1058 if (path
->reada
< 0 && objectid
) {
1059 btrfs_node_key(node
, &disk_key
, nr
);
1060 if (btrfs_disk_key_objectid(&disk_key
) != objectid
)
1063 search
= btrfs_node_blockptr(node
, nr
);
1064 if ((search
>= lowest_read
&& search
<= highest_read
) ||
1065 (search
< lowest_read
&& lowest_read
- search
<= 32768) ||
1066 (search
> highest_read
&& search
- highest_read
<= 32768)) {
1067 readahead_tree_block(root
, search
, blocksize
);
1071 if (path
->reada
< 2 && (nread
> (256 * 1024) || nscan
> 32))
1073 if(nread
> (1024 * 1024) || nscan
> 128)
1076 if (search
< lowest_read
)
1077 lowest_read
= search
;
1078 if (search
> highest_read
)
1079 highest_read
= search
;
1083 * look for key in the tree. path is filled in with nodes along the way
1084 * if key is found, we return zero and you can find the item in the leaf
1085 * level of the path (level 0)
1087 * If the key isn't found, the path points to the slot where it should
1088 * be inserted, and 1 is returned. If there are other errors during the
1089 * search a negative error number is returned.
1091 * if ins_len > 0, nodes and leaves will be split as we walk down the
1092 * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
1095 int btrfs_search_slot(struct btrfs_trans_handle
*trans
, struct btrfs_root
1096 *root
, struct btrfs_key
*key
, struct btrfs_path
*p
, int
1099 struct extent_buffer
*b
;
1105 int should_reada
= p
->reada
;
1106 u8 lowest_level
= 0;
1108 lowest_level
= p
->lowest_level
;
1109 WARN_ON(lowest_level
&& ins_len
);
1110 WARN_ON(p
->nodes
[0] != NULL
);
1111 WARN_ON(!mutex_is_locked(&root
->fs_info
->fs_mutex
));
1114 extent_buffer_get(b
);
1116 level
= btrfs_header_level(b
);
1119 wret
= btrfs_cow_block(trans
, root
, b
,
1120 p
->nodes
[level
+ 1],
1121 p
->slots
[level
+ 1],
1124 free_extent_buffer(b
);
1128 BUG_ON(!cow
&& ins_len
);
1129 if (level
!= btrfs_header_level(b
))
1131 level
= btrfs_header_level(b
);
1132 p
->nodes
[level
] = b
;
1133 ret
= check_block(root
, p
, level
);
1136 ret
= bin_search(b
, key
, level
, &slot
);
1138 if (ret
&& slot
> 0)
1140 p
->slots
[level
] = slot
;
1141 if (ins_len
> 0 && btrfs_header_nritems(b
) >=
1142 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
1143 int sret
= split_node(trans
, root
, p
, level
);
1147 b
= p
->nodes
[level
];
1148 slot
= p
->slots
[level
];
1149 } else if (ins_len
< 0) {
1150 int sret
= balance_level(trans
, root
, p
,
1154 b
= p
->nodes
[level
];
1156 btrfs_release_path(NULL
, p
);
1159 slot
= p
->slots
[level
];
1160 BUG_ON(btrfs_header_nritems(b
) == 1);
1162 /* this is only true while dropping a snapshot */
1163 if (level
== lowest_level
)
1165 bytenr
= btrfs_node_blockptr(b
, slot
);
1166 ptr_gen
= btrfs_node_ptr_generation(b
, slot
);
1168 reada_for_search(root
, p
, level
, slot
,
1170 b
= read_tree_block(root
, bytenr
,
1171 btrfs_level_size(root
, level
- 1));
1172 if (ptr_gen
!= btrfs_header_generation(b
)) {
1173 printk("block %llu bad gen wanted %llu "
1175 (unsigned long long)b
->start
,
1176 (unsigned long long)ptr_gen
,
1177 (unsigned long long)btrfs_header_generation(b
));
1180 p
->slots
[level
] = slot
;
1181 if (ins_len
> 0 && btrfs_leaf_free_space(root
, b
) <
1182 sizeof(struct btrfs_item
) + ins_len
) {
1183 int sret
= split_leaf(trans
, root
, key
,
1184 p
, ins_len
, ret
== 0);
1196 * adjust the pointers going up the tree, starting at level
1197 * making sure the right key of each node is points to 'key'.
1198 * This is used after shifting pointers to the left, so it stops
1199 * fixing up pointers when a given leaf/node is not in slot 0 of the
1202 * If this fails to write a tree block, it returns -1, but continues
1203 * fixing up the blocks in ram so the tree is consistent.
1205 static int fixup_low_keys(struct btrfs_trans_handle
*trans
,
1206 struct btrfs_root
*root
, struct btrfs_path
*path
,
1207 struct btrfs_disk_key
*key
, int level
)
1211 struct extent_buffer
*t
;
1213 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1214 int tslot
= path
->slots
[i
];
1215 if (!path
->nodes
[i
])
1218 btrfs_set_node_key(t
, key
, tslot
);
1219 btrfs_mark_buffer_dirty(path
->nodes
[i
]);
1227 * try to push data from one node into the next node left in the
1230 * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
1231 * error, and > 0 if there was no room in the left hand block.
1233 static int push_node_left(struct btrfs_trans_handle
*trans
,
1234 struct btrfs_root
*root
, struct extent_buffer
*dst
,
1235 struct extent_buffer
*src
)
1242 src_nritems
= btrfs_header_nritems(src
);
1243 dst_nritems
= btrfs_header_nritems(dst
);
1244 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1245 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1246 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1248 if (push_items
<= 0) {
1252 if (src_nritems
< push_items
)
1253 push_items
= src_nritems
;
1255 copy_extent_buffer(dst
, src
,
1256 btrfs_node_key_ptr_offset(dst_nritems
),
1257 btrfs_node_key_ptr_offset(0),
1258 push_items
* sizeof(struct btrfs_key_ptr
));
1260 if (push_items
< src_nritems
) {
1261 memmove_extent_buffer(src
, btrfs_node_key_ptr_offset(0),
1262 btrfs_node_key_ptr_offset(push_items
),
1263 (src_nritems
- push_items
) *
1264 sizeof(struct btrfs_key_ptr
));
1266 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1267 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1268 btrfs_mark_buffer_dirty(src
);
1269 btrfs_mark_buffer_dirty(dst
);
1274 * try to push data from one node into the next node right in the
1277 * returns 0 if some ptrs were pushed, < 0 if there was some horrible
1278 * error, and > 0 if there was no room in the right hand block.
1280 * this will only push up to 1/2 the contents of the left node over
1282 static int balance_node_right(struct btrfs_trans_handle
*trans
,
1283 struct btrfs_root
*root
,
1284 struct extent_buffer
*dst
,
1285 struct extent_buffer
*src
)
1293 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1294 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1296 src_nritems
= btrfs_header_nritems(src
);
1297 dst_nritems
= btrfs_header_nritems(dst
);
1298 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1299 if (push_items
<= 0)
1302 max_push
= src_nritems
/ 2 + 1;
1303 /* don't try to empty the node */
1304 if (max_push
>= src_nritems
)
1307 if (max_push
< push_items
)
1308 push_items
= max_push
;
1310 memmove_extent_buffer(dst
, btrfs_node_key_ptr_offset(push_items
),
1311 btrfs_node_key_ptr_offset(0),
1313 sizeof(struct btrfs_key_ptr
));
1315 copy_extent_buffer(dst
, src
,
1316 btrfs_node_key_ptr_offset(0),
1317 btrfs_node_key_ptr_offset(src_nritems
- push_items
),
1318 push_items
* sizeof(struct btrfs_key_ptr
));
1320 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1321 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1323 btrfs_mark_buffer_dirty(src
);
1324 btrfs_mark_buffer_dirty(dst
);
1329 * helper function to insert a new root level in the tree.
1330 * A new node is allocated, and a single item is inserted to
1331 * point to the existing root
1333 * returns zero on success or < 0 on failure.
1335 static int noinline
insert_new_root(struct btrfs_trans_handle
*trans
,
1336 struct btrfs_root
*root
,
1337 struct btrfs_path
*path
, int level
)
1341 struct extent_buffer
*lower
;
1342 struct extent_buffer
*c
;
1343 struct btrfs_disk_key lower_key
;
1345 BUG_ON(path
->nodes
[level
]);
1346 BUG_ON(path
->nodes
[level
-1] != root
->node
);
1349 root_gen
= trans
->transid
;
1353 lower
= path
->nodes
[level
-1];
1355 btrfs_item_key(lower
, &lower_key
, 0);
1357 btrfs_node_key(lower
, &lower_key
, 0);
1359 c
= __btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1360 root
->root_key
.objectid
,
1361 root_gen
, lower_key
.objectid
, level
,
1362 root
->node
->start
, 0);
1365 memset_extent_buffer(c
, 0, 0, root
->nodesize
);
1366 btrfs_set_header_nritems(c
, 1);
1367 btrfs_set_header_level(c
, level
);
1368 btrfs_set_header_bytenr(c
, c
->start
);
1369 btrfs_set_header_generation(c
, trans
->transid
);
1370 btrfs_set_header_owner(c
, root
->root_key
.objectid
);
1372 write_extent_buffer(c
, root
->fs_info
->fsid
,
1373 (unsigned long)btrfs_header_fsid(c
),
1375 btrfs_set_node_key(c
, &lower_key
, 0);
1376 btrfs_set_node_blockptr(c
, 0, lower
->start
);
1377 lower_gen
= btrfs_header_generation(lower
);
1378 WARN_ON(lower_gen
== 0);
1380 btrfs_set_node_ptr_generation(c
, 0, lower_gen
);
1382 btrfs_mark_buffer_dirty(c
);
1384 /* the super has an extra ref to root->node */
1385 free_extent_buffer(root
->node
);
1387 add_root_to_dirty_list(root
);
1388 extent_buffer_get(c
);
1389 path
->nodes
[level
] = c
;
1390 path
->slots
[level
] = 0;
1392 if (root
->ref_cows
&& lower_gen
!= trans
->transid
) {
1393 struct btrfs_path
*back_path
= btrfs_alloc_path();
1395 ret
= btrfs_insert_extent_backref(trans
,
1396 root
->fs_info
->extent_root
,
1398 root
->root_key
.objectid
,
1399 trans
->transid
, 0, 0);
1401 btrfs_free_path(back_path
);
1407 * worker function to insert a single pointer in a node.
1408 * the node should have enough room for the pointer already
1410 * slot and level indicate where you want the key to go, and
1411 * blocknr is the block the key points to.
1413 * returns zero on success and < 0 on any error
1415 static int insert_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
1416 *root
, struct btrfs_path
*path
, struct btrfs_disk_key
1417 *key
, u64 bytenr
, int slot
, int level
)
1419 struct extent_buffer
*lower
;
1422 BUG_ON(!path
->nodes
[level
]);
1423 lower
= path
->nodes
[level
];
1424 nritems
= btrfs_header_nritems(lower
);
1427 if (nritems
== BTRFS_NODEPTRS_PER_BLOCK(root
))
1429 if (slot
!= nritems
) {
1430 memmove_extent_buffer(lower
,
1431 btrfs_node_key_ptr_offset(slot
+ 1),
1432 btrfs_node_key_ptr_offset(slot
),
1433 (nritems
- slot
) * sizeof(struct btrfs_key_ptr
));
1435 btrfs_set_node_key(lower
, key
, slot
);
1436 btrfs_set_node_blockptr(lower
, slot
, bytenr
);
1437 WARN_ON(trans
->transid
== 0);
1438 btrfs_set_node_ptr_generation(lower
, slot
, trans
->transid
);
1439 btrfs_set_header_nritems(lower
, nritems
+ 1);
1440 btrfs_mark_buffer_dirty(lower
);
1445 * split the node at the specified level in path in two.
1446 * The path is corrected to point to the appropriate node after the split
1448 * Before splitting this tries to make some room in the node by pushing
1449 * left and right, if either one works, it returns right away.
1451 * returns 0 on success and < 0 on failure
1453 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
1454 *root
, struct btrfs_path
*path
, int level
)
1457 struct extent_buffer
*c
;
1458 struct extent_buffer
*split
;
1459 struct btrfs_disk_key disk_key
;
1465 c
= path
->nodes
[level
];
1466 WARN_ON(btrfs_header_generation(c
) != trans
->transid
);
1467 if (c
== root
->node
) {
1468 /* trying to split the root, lets make a new one */
1469 ret
= insert_new_root(trans
, root
, path
, level
+ 1);
1473 ret
= push_nodes_for_insert(trans
, root
, path
, level
);
1474 c
= path
->nodes
[level
];
1475 if (!ret
&& btrfs_header_nritems(c
) <
1476 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1)
1482 c_nritems
= btrfs_header_nritems(c
);
1484 root_gen
= trans
->transid
;
1488 btrfs_node_key(c
, &disk_key
, 0);
1489 split
= __btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1490 root
->root_key
.objectid
,
1492 btrfs_disk_key_objectid(&disk_key
),
1493 level
, c
->start
, 0);
1495 return PTR_ERR(split
);
1497 btrfs_set_header_flags(split
, btrfs_header_flags(c
));
1498 btrfs_set_header_level(split
, btrfs_header_level(c
));
1499 btrfs_set_header_bytenr(split
, split
->start
);
1500 btrfs_set_header_generation(split
, trans
->transid
);
1501 btrfs_set_header_owner(split
, root
->root_key
.objectid
);
1502 btrfs_set_header_flags(split
, 0);
1503 write_extent_buffer(split
, root
->fs_info
->fsid
,
1504 (unsigned long)btrfs_header_fsid(split
),
1507 mid
= (c_nritems
+ 1) / 2;
1509 copy_extent_buffer(split
, c
,
1510 btrfs_node_key_ptr_offset(0),
1511 btrfs_node_key_ptr_offset(mid
),
1512 (c_nritems
- mid
) * sizeof(struct btrfs_key_ptr
));
1513 btrfs_set_header_nritems(split
, c_nritems
- mid
);
1514 btrfs_set_header_nritems(c
, mid
);
1517 btrfs_mark_buffer_dirty(c
);
1518 btrfs_mark_buffer_dirty(split
);
1520 btrfs_node_key(split
, &disk_key
, 0);
1521 wret
= insert_ptr(trans
, root
, path
, &disk_key
, split
->start
,
1522 path
->slots
[level
+ 1] + 1,
1527 if (path
->slots
[level
] >= mid
) {
1528 path
->slots
[level
] -= mid
;
1529 free_extent_buffer(c
);
1530 path
->nodes
[level
] = split
;
1531 path
->slots
[level
+ 1] += 1;
1533 free_extent_buffer(split
);
1539 * how many bytes are required to store the items in a leaf. start
1540 * and nr indicate which items in the leaf to check. This totals up the
1541 * space used both by the item structs and the item data
1543 static int leaf_space_used(struct extent_buffer
*l
, int start
, int nr
)
1546 int nritems
= btrfs_header_nritems(l
);
1547 int end
= min(nritems
, start
+ nr
) - 1;
1551 data_len
= btrfs_item_end_nr(l
, start
);
1552 data_len
= data_len
- btrfs_item_offset_nr(l
, end
);
1553 data_len
+= sizeof(struct btrfs_item
) * nr
;
1554 WARN_ON(data_len
< 0);
1559 * The space between the end of the leaf items and
1560 * the start of the leaf data. IOW, how much room
1561 * the leaf has left for both items and data
1563 int btrfs_leaf_free_space(struct btrfs_root
*root
, struct extent_buffer
*leaf
)
1565 int nritems
= btrfs_header_nritems(leaf
);
1567 ret
= BTRFS_LEAF_DATA_SIZE(root
) - leaf_space_used(leaf
, 0, nritems
);
1569 printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
1570 ret
, (unsigned long) BTRFS_LEAF_DATA_SIZE(root
),
1571 leaf_space_used(leaf
, 0, nritems
), nritems
);
1577 * push some data in the path leaf to the right, trying to free up at
1578 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1580 * returns 1 if the push failed because the other node didn't have enough
1581 * room, 0 if everything worked out and < 0 if there were major errors.
1583 static int push_leaf_right(struct btrfs_trans_handle
*trans
, struct btrfs_root
1584 *root
, struct btrfs_path
*path
, int data_size
,
1587 struct extent_buffer
*left
= path
->nodes
[0];
1588 struct extent_buffer
*right
;
1589 struct extent_buffer
*upper
;
1590 struct btrfs_disk_key disk_key
;
1596 struct btrfs_item
*item
;
1604 slot
= path
->slots
[1];
1605 if (!path
->nodes
[1]) {
1608 upper
= path
->nodes
[1];
1609 if (slot
>= btrfs_header_nritems(upper
) - 1)
1612 right
= read_tree_block(root
, btrfs_node_blockptr(upper
, slot
+ 1),
1614 free_space
= btrfs_leaf_free_space(root
, right
);
1615 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1616 free_extent_buffer(right
);
1620 /* cow and double check */
1621 ret
= btrfs_cow_block(trans
, root
, right
, upper
,
1624 free_extent_buffer(right
);
1627 free_space
= btrfs_leaf_free_space(root
, right
);
1628 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1629 free_extent_buffer(right
);
1633 left_nritems
= btrfs_header_nritems(left
);
1634 if (left_nritems
== 0) {
1635 free_extent_buffer(right
);
1644 i
= left_nritems
- 1;
1646 item
= btrfs_item_nr(left
, i
);
1648 if (path
->slots
[0] == i
)
1649 push_space
+= data_size
+ sizeof(*item
);
1651 if (!left
->map_token
) {
1652 map_extent_buffer(left
, (unsigned long)item
,
1653 sizeof(struct btrfs_item
),
1654 &left
->map_token
, &left
->kaddr
,
1655 &left
->map_start
, &left
->map_len
,
1659 this_item_size
= btrfs_item_size(left
, item
);
1660 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1663 push_space
+= this_item_size
+ sizeof(*item
);
1668 if (left
->map_token
) {
1669 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1670 left
->map_token
= NULL
;
1673 if (push_items
== 0) {
1674 free_extent_buffer(right
);
1678 if (!empty
&& push_items
== left_nritems
)
1681 /* push left to right */
1682 right_nritems
= btrfs_header_nritems(right
);
1684 push_space
= btrfs_item_end_nr(left
, left_nritems
- push_items
);
1685 push_space
-= leaf_data_end(root
, left
);
1687 /* make room in the right data area */
1688 data_end
= leaf_data_end(root
, right
);
1689 memmove_extent_buffer(right
,
1690 btrfs_leaf_data(right
) + data_end
- push_space
,
1691 btrfs_leaf_data(right
) + data_end
,
1692 BTRFS_LEAF_DATA_SIZE(root
) - data_end
);
1694 /* copy from the left data area */
1695 copy_extent_buffer(right
, left
, btrfs_leaf_data(right
) +
1696 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1697 btrfs_leaf_data(left
) + leaf_data_end(root
, left
),
1700 memmove_extent_buffer(right
, btrfs_item_nr_offset(push_items
),
1701 btrfs_item_nr_offset(0),
1702 right_nritems
* sizeof(struct btrfs_item
));
1704 /* copy the items from left to right */
1705 copy_extent_buffer(right
, left
, btrfs_item_nr_offset(0),
1706 btrfs_item_nr_offset(left_nritems
- push_items
),
1707 push_items
* sizeof(struct btrfs_item
));
1709 /* update the item pointers */
1710 right_nritems
+= push_items
;
1711 btrfs_set_header_nritems(right
, right_nritems
);
1712 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1713 for (i
= 0; i
< right_nritems
; i
++) {
1714 item
= btrfs_item_nr(right
, i
);
1715 if (!right
->map_token
) {
1716 map_extent_buffer(right
, (unsigned long)item
,
1717 sizeof(struct btrfs_item
),
1718 &right
->map_token
, &right
->kaddr
,
1719 &right
->map_start
, &right
->map_len
,
1722 push_space
-= btrfs_item_size(right
, item
);
1723 btrfs_set_item_offset(right
, item
, push_space
);
1726 if (right
->map_token
) {
1727 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1728 right
->map_token
= NULL
;
1730 left_nritems
-= push_items
;
1731 btrfs_set_header_nritems(left
, left_nritems
);
1734 btrfs_mark_buffer_dirty(left
);
1735 btrfs_mark_buffer_dirty(right
);
1737 btrfs_item_key(right
, &disk_key
, 0);
1738 btrfs_set_node_key(upper
, &disk_key
, slot
+ 1);
1739 btrfs_mark_buffer_dirty(upper
);
1741 /* then fixup the leaf pointer in the path */
1742 if (path
->slots
[0] >= left_nritems
) {
1743 path
->slots
[0] -= left_nritems
;
1744 free_extent_buffer(path
->nodes
[0]);
1745 path
->nodes
[0] = right
;
1746 path
->slots
[1] += 1;
1748 free_extent_buffer(right
);
1753 * push some data in the path leaf to the left, trying to free up at
1754 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1756 static int push_leaf_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1757 *root
, struct btrfs_path
*path
, int data_size
,
1760 struct btrfs_disk_key disk_key
;
1761 struct extent_buffer
*right
= path
->nodes
[0];
1762 struct extent_buffer
*left
;
1768 struct btrfs_item
*item
;
1769 u32 old_left_nritems
;
1775 u32 old_left_item_size
;
1777 slot
= path
->slots
[1];
1780 if (!path
->nodes
[1])
1783 right_nritems
= btrfs_header_nritems(right
);
1784 if (right_nritems
== 0) {
1788 left
= read_tree_block(root
, btrfs_node_blockptr(path
->nodes
[1],
1789 slot
- 1), root
->leafsize
);
1790 free_space
= btrfs_leaf_free_space(root
, left
);
1791 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1792 free_extent_buffer(left
);
1796 /* cow and double check */
1797 ret
= btrfs_cow_block(trans
, root
, left
,
1798 path
->nodes
[1], slot
- 1, &left
);
1800 /* we hit -ENOSPC, but it isn't fatal here */
1801 free_extent_buffer(left
);
1805 free_space
= btrfs_leaf_free_space(root
, left
);
1806 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1807 free_extent_buffer(left
);
1814 nr
= right_nritems
- 1;
1816 for (i
= 0; i
< nr
; i
++) {
1817 item
= btrfs_item_nr(right
, i
);
1818 if (!right
->map_token
) {
1819 map_extent_buffer(right
, (unsigned long)item
,
1820 sizeof(struct btrfs_item
),
1821 &right
->map_token
, &right
->kaddr
,
1822 &right
->map_start
, &right
->map_len
,
1826 if (path
->slots
[0] == i
)
1827 push_space
+= data_size
+ sizeof(*item
);
1829 this_item_size
= btrfs_item_size(right
, item
);
1830 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1834 push_space
+= this_item_size
+ sizeof(*item
);
1837 if (right
->map_token
) {
1838 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1839 right
->map_token
= NULL
;
1842 if (push_items
== 0) {
1843 free_extent_buffer(left
);
1846 if (!empty
&& push_items
== btrfs_header_nritems(right
))
1849 /* push data from right to left */
1850 copy_extent_buffer(left
, right
,
1851 btrfs_item_nr_offset(btrfs_header_nritems(left
)),
1852 btrfs_item_nr_offset(0),
1853 push_items
* sizeof(struct btrfs_item
));
1855 push_space
= BTRFS_LEAF_DATA_SIZE(root
) -
1856 btrfs_item_offset_nr(right
, push_items
-1);
1858 copy_extent_buffer(left
, right
, btrfs_leaf_data(left
) +
1859 leaf_data_end(root
, left
) - push_space
,
1860 btrfs_leaf_data(right
) +
1861 btrfs_item_offset_nr(right
, push_items
- 1),
1863 old_left_nritems
= btrfs_header_nritems(left
);
1864 BUG_ON(old_left_nritems
< 0);
1866 old_left_item_size
= btrfs_item_offset_nr(left
, old_left_nritems
- 1);
1867 for (i
= old_left_nritems
; i
< old_left_nritems
+ push_items
; i
++) {
1870 item
= btrfs_item_nr(left
, i
);
1871 if (!left
->map_token
) {
1872 map_extent_buffer(left
, (unsigned long)item
,
1873 sizeof(struct btrfs_item
),
1874 &left
->map_token
, &left
->kaddr
,
1875 &left
->map_start
, &left
->map_len
,
1879 ioff
= btrfs_item_offset(left
, item
);
1880 btrfs_set_item_offset(left
, item
,
1881 ioff
- (BTRFS_LEAF_DATA_SIZE(root
) - old_left_item_size
));
1883 btrfs_set_header_nritems(left
, old_left_nritems
+ push_items
);
1884 if (left
->map_token
) {
1885 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1886 left
->map_token
= NULL
;
1889 /* fixup right node */
1890 if (push_items
> right_nritems
) {
1891 printk("push items %d nr %u\n", push_items
, right_nritems
);
1895 if (push_items
< right_nritems
) {
1896 push_space
= btrfs_item_offset_nr(right
, push_items
- 1) -
1897 leaf_data_end(root
, right
);
1898 memmove_extent_buffer(right
, btrfs_leaf_data(right
) +
1899 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1900 btrfs_leaf_data(right
) +
1901 leaf_data_end(root
, right
), push_space
);
1903 memmove_extent_buffer(right
, btrfs_item_nr_offset(0),
1904 btrfs_item_nr_offset(push_items
),
1905 (btrfs_header_nritems(right
) - push_items
) *
1906 sizeof(struct btrfs_item
));
1908 right_nritems
-= push_items
;
1909 btrfs_set_header_nritems(right
, right_nritems
);
1910 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1911 for (i
= 0; i
< right_nritems
; i
++) {
1912 item
= btrfs_item_nr(right
, i
);
1914 if (!right
->map_token
) {
1915 map_extent_buffer(right
, (unsigned long)item
,
1916 sizeof(struct btrfs_item
),
1917 &right
->map_token
, &right
->kaddr
,
1918 &right
->map_start
, &right
->map_len
,
1922 push_space
= push_space
- btrfs_item_size(right
, item
);
1923 btrfs_set_item_offset(right
, item
, push_space
);
1925 if (right
->map_token
) {
1926 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1927 right
->map_token
= NULL
;
1930 btrfs_mark_buffer_dirty(left
);
1932 btrfs_mark_buffer_dirty(right
);
1934 btrfs_item_key(right
, &disk_key
, 0);
1935 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1939 /* then fixup the leaf pointer in the path */
1940 if (path
->slots
[0] < push_items
) {
1941 path
->slots
[0] += old_left_nritems
;
1942 free_extent_buffer(path
->nodes
[0]);
1943 path
->nodes
[0] = left
;
1944 path
->slots
[1] -= 1;
1946 free_extent_buffer(left
);
1947 path
->slots
[0] -= push_items
;
1949 BUG_ON(path
->slots
[0] < 0);
1954 * split the path's leaf in two, making sure there is at least data_size
1955 * available for the resulting leaf level of the path.
1957 * returns 0 if all went well and < 0 on failure.
1959 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
1960 *root
, struct btrfs_key
*ins_key
,
1961 struct btrfs_path
*path
, int data_size
, int extend
)
1964 struct extent_buffer
*l
;
1968 struct extent_buffer
*right
;
1969 int space_needed
= data_size
+ sizeof(struct btrfs_item
);
1976 int num_doubles
= 0;
1977 struct btrfs_disk_key disk_key
;
1980 space_needed
= data_size
;
1983 root_gen
= trans
->transid
;
1987 /* first try to make some room by pushing left and right */
1988 if (ins_key
->type
!= BTRFS_DIR_ITEM_KEY
) {
1989 wret
= push_leaf_right(trans
, root
, path
, data_size
, 0);
1994 wret
= push_leaf_left(trans
, root
, path
, data_size
, 0);
2000 /* did the pushes work? */
2001 if (btrfs_leaf_free_space(root
, l
) >= space_needed
)
2005 if (!path
->nodes
[1]) {
2006 ret
= insert_new_root(trans
, root
, path
, 1);
2013 slot
= path
->slots
[0];
2014 nritems
= btrfs_header_nritems(l
);
2015 mid
= (nritems
+ 1)/ 2;
2017 btrfs_item_key(l
, &disk_key
, 0);
2019 right
= __btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
2020 root
->root_key
.objectid
,
2021 root_gen
, disk_key
.objectid
, 0,
2024 return PTR_ERR(right
);
2026 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
2027 btrfs_set_header_bytenr(right
, right
->start
);
2028 btrfs_set_header_generation(right
, trans
->transid
);
2029 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
2030 btrfs_set_header_level(right
, 0);
2031 write_extent_buffer(right
, root
->fs_info
->fsid
,
2032 (unsigned long)btrfs_header_fsid(right
),
2036 leaf_space_used(l
, mid
, nritems
- mid
) + space_needed
>
2037 BTRFS_LEAF_DATA_SIZE(root
)) {
2038 if (slot
>= nritems
) {
2039 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2040 btrfs_set_header_nritems(right
, 0);
2041 wret
= insert_ptr(trans
, root
, path
,
2042 &disk_key
, right
->start
,
2043 path
->slots
[1] + 1, 1);
2046 free_extent_buffer(path
->nodes
[0]);
2047 path
->nodes
[0] = right
;
2049 path
->slots
[1] += 1;
2053 if (mid
!= nritems
&&
2054 leaf_space_used(l
, mid
, nritems
- mid
) +
2055 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2060 if (leaf_space_used(l
, 0, mid
+ 1) + space_needed
>
2061 BTRFS_LEAF_DATA_SIZE(root
)) {
2062 if (!extend
&& slot
== 0) {
2063 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2064 btrfs_set_header_nritems(right
, 0);
2065 wret
= insert_ptr(trans
, root
, path
,
2071 free_extent_buffer(path
->nodes
[0]);
2072 path
->nodes
[0] = right
;
2074 if (path
->slots
[1] == 0) {
2075 wret
= fixup_low_keys(trans
, root
,
2076 path
, &disk_key
, 1);
2081 } else if (extend
&& slot
== 0) {
2085 if (mid
!= nritems
&&
2086 leaf_space_used(l
, mid
, nritems
- mid
) +
2087 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2093 nritems
= nritems
- mid
;
2094 btrfs_set_header_nritems(right
, nritems
);
2095 data_copy_size
= btrfs_item_end_nr(l
, mid
) - leaf_data_end(root
, l
);
2097 copy_extent_buffer(right
, l
, btrfs_item_nr_offset(0),
2098 btrfs_item_nr_offset(mid
),
2099 nritems
* sizeof(struct btrfs_item
));
2101 copy_extent_buffer(right
, l
,
2102 btrfs_leaf_data(right
) + BTRFS_LEAF_DATA_SIZE(root
) -
2103 data_copy_size
, btrfs_leaf_data(l
) +
2104 leaf_data_end(root
, l
), data_copy_size
);
2106 rt_data_off
= BTRFS_LEAF_DATA_SIZE(root
) -
2107 btrfs_item_end_nr(l
, mid
);
2109 for (i
= 0; i
< nritems
; i
++) {
2110 struct btrfs_item
*item
= btrfs_item_nr(right
, i
);
2113 if (!right
->map_token
) {
2114 map_extent_buffer(right
, (unsigned long)item
,
2115 sizeof(struct btrfs_item
),
2116 &right
->map_token
, &right
->kaddr
,
2117 &right
->map_start
, &right
->map_len
,
2121 ioff
= btrfs_item_offset(right
, item
);
2122 btrfs_set_item_offset(right
, item
, ioff
+ rt_data_off
);
2125 if (right
->map_token
) {
2126 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
2127 right
->map_token
= NULL
;
2130 btrfs_set_header_nritems(l
, mid
);
2132 btrfs_item_key(right
, &disk_key
, 0);
2133 wret
= insert_ptr(trans
, root
, path
, &disk_key
, right
->start
,
2134 path
->slots
[1] + 1, 1);
2138 btrfs_mark_buffer_dirty(right
);
2139 btrfs_mark_buffer_dirty(l
);
2140 BUG_ON(path
->slots
[0] != slot
);
2143 free_extent_buffer(path
->nodes
[0]);
2144 path
->nodes
[0] = right
;
2145 path
->slots
[0] -= mid
;
2146 path
->slots
[1] += 1;
2148 free_extent_buffer(right
);
2150 BUG_ON(path
->slots
[0] < 0);
2153 BUG_ON(num_doubles
!= 0);
2160 int btrfs_truncate_item(struct btrfs_trans_handle
*trans
,
2161 struct btrfs_root
*root
,
2162 struct btrfs_path
*path
,
2163 u32 new_size
, int from_end
)
2168 struct extent_buffer
*leaf
;
2169 struct btrfs_item
*item
;
2171 unsigned int data_end
;
2172 unsigned int old_data_start
;
2173 unsigned int old_size
;
2174 unsigned int size_diff
;
2177 slot_orig
= path
->slots
[0];
2178 leaf
= path
->nodes
[0];
2179 slot
= path
->slots
[0];
2181 old_size
= btrfs_item_size_nr(leaf
, slot
);
2182 if (old_size
== new_size
)
2185 nritems
= btrfs_header_nritems(leaf
);
2186 data_end
= leaf_data_end(root
, leaf
);
2188 old_data_start
= btrfs_item_offset_nr(leaf
, slot
);
2190 size_diff
= old_size
- new_size
;
2193 BUG_ON(slot
>= nritems
);
2196 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2198 /* first correct the data pointers */
2199 for (i
= slot
; i
< nritems
; i
++) {
2201 item
= btrfs_item_nr(leaf
, i
);
2203 if (!leaf
->map_token
) {
2204 map_extent_buffer(leaf
, (unsigned long)item
,
2205 sizeof(struct btrfs_item
),
2206 &leaf
->map_token
, &leaf
->kaddr
,
2207 &leaf
->map_start
, &leaf
->map_len
,
2211 ioff
= btrfs_item_offset(leaf
, item
);
2212 btrfs_set_item_offset(leaf
, item
, ioff
+ size_diff
);
2215 if (leaf
->map_token
) {
2216 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2217 leaf
->map_token
= NULL
;
2220 /* shift the data */
2222 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2223 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2224 data_end
, old_data_start
+ new_size
- data_end
);
2226 struct btrfs_disk_key disk_key
;
2229 btrfs_item_key(leaf
, &disk_key
, slot
);
2231 if (btrfs_disk_key_type(&disk_key
) == BTRFS_EXTENT_DATA_KEY
) {
2233 struct btrfs_file_extent_item
*fi
;
2235 fi
= btrfs_item_ptr(leaf
, slot
,
2236 struct btrfs_file_extent_item
);
2237 fi
= (struct btrfs_file_extent_item
*)(
2238 (unsigned long)fi
- size_diff
);
2240 if (btrfs_file_extent_type(leaf
, fi
) ==
2241 BTRFS_FILE_EXTENT_INLINE
) {
2242 ptr
= btrfs_item_ptr_offset(leaf
, slot
);
2243 memmove_extent_buffer(leaf
, ptr
,
2245 offsetof(struct btrfs_file_extent_item
,
2250 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2251 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2252 data_end
, old_data_start
- data_end
);
2254 offset
= btrfs_disk_key_offset(&disk_key
);
2255 btrfs_set_disk_key_offset(&disk_key
, offset
+ size_diff
);
2256 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2258 fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2261 item
= btrfs_item_nr(leaf
, slot
);
2262 btrfs_set_item_size(leaf
, item
, new_size
);
2263 btrfs_mark_buffer_dirty(leaf
);
2266 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2267 btrfs_print_leaf(root
, leaf
);
2273 int btrfs_extend_item(struct btrfs_trans_handle
*trans
,
2274 struct btrfs_root
*root
, struct btrfs_path
*path
,
2280 struct extent_buffer
*leaf
;
2281 struct btrfs_item
*item
;
2283 unsigned int data_end
;
2284 unsigned int old_data
;
2285 unsigned int old_size
;
2288 slot_orig
= path
->slots
[0];
2289 leaf
= path
->nodes
[0];
2291 nritems
= btrfs_header_nritems(leaf
);
2292 data_end
= leaf_data_end(root
, leaf
);
2294 if (btrfs_leaf_free_space(root
, leaf
) < data_size
) {
2295 btrfs_print_leaf(root
, leaf
);
2298 slot
= path
->slots
[0];
2299 old_data
= btrfs_item_end_nr(leaf
, slot
);
2302 if (slot
>= nritems
) {
2303 btrfs_print_leaf(root
, leaf
);
2304 printk("slot %d too large, nritems %d\n", slot
, nritems
);
2309 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2311 /* first correct the data pointers */
2312 for (i
= slot
; i
< nritems
; i
++) {
2314 item
= btrfs_item_nr(leaf
, i
);
2316 if (!leaf
->map_token
) {
2317 map_extent_buffer(leaf
, (unsigned long)item
,
2318 sizeof(struct btrfs_item
),
2319 &leaf
->map_token
, &leaf
->kaddr
,
2320 &leaf
->map_start
, &leaf
->map_len
,
2323 ioff
= btrfs_item_offset(leaf
, item
);
2324 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2327 if (leaf
->map_token
) {
2328 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2329 leaf
->map_token
= NULL
;
2332 /* shift the data */
2333 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2334 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2335 data_end
, old_data
- data_end
);
2337 data_end
= old_data
;
2338 old_size
= btrfs_item_size_nr(leaf
, slot
);
2339 item
= btrfs_item_nr(leaf
, slot
);
2340 btrfs_set_item_size(leaf
, item
, old_size
+ data_size
);
2341 btrfs_mark_buffer_dirty(leaf
);
2344 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2345 btrfs_print_leaf(root
, leaf
);
2352 * Given a key and some data, insert an item into the tree.
2353 * This does all the path init required, making room in the tree if needed.
2355 int btrfs_insert_empty_items(struct btrfs_trans_handle
*trans
,
2356 struct btrfs_root
*root
,
2357 struct btrfs_path
*path
,
2358 struct btrfs_key
*cpu_key
, u32
*data_size
,
2361 struct extent_buffer
*leaf
;
2362 struct btrfs_item
*item
;
2370 unsigned int data_end
;
2371 struct btrfs_disk_key disk_key
;
2373 for (i
= 0; i
< nr
; i
++) {
2374 total_data
+= data_size
[i
];
2377 /* create a root if there isn't one */
2381 total_size
= total_data
+ (nr
- 1) * sizeof(struct btrfs_item
);
2382 ret
= btrfs_search_slot(trans
, root
, cpu_key
, path
, total_size
, 1);
2389 slot_orig
= path
->slots
[0];
2390 leaf
= path
->nodes
[0];
2392 nritems
= btrfs_header_nritems(leaf
);
2393 data_end
= leaf_data_end(root
, leaf
);
2395 if (btrfs_leaf_free_space(root
, leaf
) <
2396 sizeof(struct btrfs_item
) + total_size
) {
2397 btrfs_print_leaf(root
, leaf
);
2398 printk("not enough freespace need %u have %d\n",
2399 total_size
, btrfs_leaf_free_space(root
, leaf
));
2403 slot
= path
->slots
[0];
2406 if (slot
!= nritems
) {
2408 unsigned int old_data
= btrfs_item_end_nr(leaf
, slot
);
2410 if (old_data
< data_end
) {
2411 btrfs_print_leaf(root
, leaf
);
2412 printk("slot %d old_data %d data_end %d\n",
2413 slot
, old_data
, data_end
);
2417 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2419 /* first correct the data pointers */
2420 WARN_ON(leaf
->map_token
);
2421 for (i
= slot
; i
< nritems
; i
++) {
2424 item
= btrfs_item_nr(leaf
, i
);
2425 if (!leaf
->map_token
) {
2426 map_extent_buffer(leaf
, (unsigned long)item
,
2427 sizeof(struct btrfs_item
),
2428 &leaf
->map_token
, &leaf
->kaddr
,
2429 &leaf
->map_start
, &leaf
->map_len
,
2433 ioff
= btrfs_item_offset(leaf
, item
);
2434 btrfs_set_item_offset(leaf
, item
, ioff
- total_data
);
2436 if (leaf
->map_token
) {
2437 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2438 leaf
->map_token
= NULL
;
2441 /* shift the items */
2442 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ nr
),
2443 btrfs_item_nr_offset(slot
),
2444 (nritems
- slot
) * sizeof(struct btrfs_item
));
2446 /* shift the data */
2447 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2448 data_end
- total_data
, btrfs_leaf_data(leaf
) +
2449 data_end
, old_data
- data_end
);
2450 data_end
= old_data
;
2453 /* setup the item for the new data */
2454 for (i
= 0; i
< nr
; i
++) {
2455 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
+ i
);
2456 btrfs_set_item_key(leaf
, &disk_key
, slot
+ i
);
2457 item
= btrfs_item_nr(leaf
, slot
+ i
);
2458 btrfs_set_item_offset(leaf
, item
, data_end
- data_size
[i
]);
2459 data_end
-= data_size
[i
];
2460 btrfs_set_item_size(leaf
, item
, data_size
[i
]);
2462 btrfs_set_header_nritems(leaf
, nritems
+ nr
);
2463 btrfs_mark_buffer_dirty(leaf
);
2467 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
);
2468 ret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2471 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2472 btrfs_print_leaf(root
, leaf
);
2481 * Given a key and some data, insert an item into the tree.
2482 * This does all the path init required, making room in the tree if needed.
2484 int btrfs_insert_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
2485 *root
, struct btrfs_key
*cpu_key
, void *data
, u32
2489 struct btrfs_path
*path
;
2490 struct extent_buffer
*leaf
;
2493 path
= btrfs_alloc_path();
2495 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
2497 leaf
= path
->nodes
[0];
2498 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2499 write_extent_buffer(leaf
, data
, ptr
, data_size
);
2500 btrfs_mark_buffer_dirty(leaf
);
2502 btrfs_free_path(path
);
2507 * delete the pointer from a given node.
2509 * If the delete empties a node, the node is removed from the tree,
2510 * continuing all the way the root if required. The root is converted into
2511 * a leaf if all the nodes are emptied.
2513 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2514 struct btrfs_path
*path
, int level
, int slot
)
2516 struct extent_buffer
*parent
= path
->nodes
[level
];
2521 nritems
= btrfs_header_nritems(parent
);
2522 if (slot
!= nritems
-1) {
2523 memmove_extent_buffer(parent
,
2524 btrfs_node_key_ptr_offset(slot
),
2525 btrfs_node_key_ptr_offset(slot
+ 1),
2526 sizeof(struct btrfs_key_ptr
) *
2527 (nritems
- slot
- 1));
2530 btrfs_set_header_nritems(parent
, nritems
);
2531 if (nritems
== 0 && parent
== root
->node
) {
2532 BUG_ON(btrfs_header_level(root
->node
) != 1);
2533 /* just turn the root into a leaf and break */
2534 btrfs_set_header_level(root
->node
, 0);
2535 } else if (slot
== 0) {
2536 struct btrfs_disk_key disk_key
;
2538 btrfs_node_key(parent
, &disk_key
, 0);
2539 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, level
+ 1);
2543 btrfs_mark_buffer_dirty(parent
);
2548 * delete the item at the leaf level in path. If that empties
2549 * the leaf, remove it from the tree
2551 int btrfs_del_items(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2552 struct btrfs_path
*path
, int slot
, int nr
)
2554 struct extent_buffer
*leaf
;
2555 struct btrfs_item
*item
;
2563 leaf
= path
->nodes
[0];
2564 last_off
= btrfs_item_offset_nr(leaf
, slot
+ nr
- 1);
2566 for (i
= 0; i
< nr
; i
++)
2567 dsize
+= btrfs_item_size_nr(leaf
, slot
+ i
);
2569 nritems
= btrfs_header_nritems(leaf
);
2571 if (slot
+ nr
!= nritems
) {
2573 int data_end
= leaf_data_end(root
, leaf
);
2575 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2577 btrfs_leaf_data(leaf
) + data_end
,
2578 last_off
- data_end
);
2580 for (i
= slot
+ nr
; i
< nritems
; i
++) {
2583 item
= btrfs_item_nr(leaf
, i
);
2584 if (!leaf
->map_token
) {
2585 map_extent_buffer(leaf
, (unsigned long)item
,
2586 sizeof(struct btrfs_item
),
2587 &leaf
->map_token
, &leaf
->kaddr
,
2588 &leaf
->map_start
, &leaf
->map_len
,
2591 ioff
= btrfs_item_offset(leaf
, item
);
2592 btrfs_set_item_offset(leaf
, item
, ioff
+ dsize
);
2595 if (leaf
->map_token
) {
2596 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2597 leaf
->map_token
= NULL
;
2600 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
),
2601 btrfs_item_nr_offset(slot
+ nr
),
2602 sizeof(struct btrfs_item
) *
2603 (nritems
- slot
- nr
));
2605 btrfs_set_header_nritems(leaf
, nritems
- nr
);
2608 /* delete the leaf if we've emptied it */
2610 if (leaf
== root
->node
) {
2611 btrfs_set_header_level(leaf
, 0);
2613 u64 root_gen
= btrfs_header_generation(path
->nodes
[1]);
2614 clean_tree_block(trans
, root
, leaf
);
2615 wait_on_tree_block_writeback(root
, leaf
);
2616 wret
= del_ptr(trans
, root
, path
, 1, path
->slots
[1]);
2619 wret
= btrfs_free_extent(trans
, root
,
2620 leaf
->start
, leaf
->len
,
2621 btrfs_header_owner(path
->nodes
[1]),
2627 int used
= leaf_space_used(leaf
, 0, nritems
);
2629 struct btrfs_disk_key disk_key
;
2631 btrfs_item_key(leaf
, &disk_key
, 0);
2632 wret
= fixup_low_keys(trans
, root
, path
,
2638 /* delete the leaf if it is mostly empty */
2639 if (used
< BTRFS_LEAF_DATA_SIZE(root
) / 4) {
2640 /* push_leaf_left fixes the path.
2641 * make sure the path still points to our leaf
2642 * for possible call to del_ptr below
2644 slot
= path
->slots
[1];
2645 extent_buffer_get(leaf
);
2647 wret
= push_leaf_left(trans
, root
, path
, 1, 1);
2648 if (wret
< 0 && wret
!= -ENOSPC
)
2651 if (path
->nodes
[0] == leaf
&&
2652 btrfs_header_nritems(leaf
)) {
2653 wret
= push_leaf_right(trans
, root
, path
, 1, 1);
2654 if (wret
< 0 && wret
!= -ENOSPC
)
2658 if (btrfs_header_nritems(leaf
) == 0) {
2660 u64 bytenr
= leaf
->start
;
2661 u32 blocksize
= leaf
->len
;
2663 root_gen
= btrfs_header_generation(
2666 clean_tree_block(trans
, root
, leaf
);
2667 wait_on_tree_block_writeback(root
, leaf
);
2669 wret
= del_ptr(trans
, root
, path
, 1, slot
);
2673 free_extent_buffer(leaf
);
2674 wret
= btrfs_free_extent(trans
, root
, bytenr
,
2676 btrfs_header_owner(path
->nodes
[1]),
2681 btrfs_mark_buffer_dirty(leaf
);
2682 free_extent_buffer(leaf
);
2685 btrfs_mark_buffer_dirty(leaf
);
2692 * walk up the tree as far as required to find the previous leaf.
2693 * returns 0 if it found something or 1 if there are no lesser leaves.
2694 * returns < 0 on io errors.
2696 int btrfs_prev_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2701 struct extent_buffer
*c
;
2702 struct extent_buffer
*next
= NULL
;
2704 while(level
< BTRFS_MAX_LEVEL
) {
2705 if (!path
->nodes
[level
])
2708 slot
= path
->slots
[level
];
2709 c
= path
->nodes
[level
];
2712 if (level
== BTRFS_MAX_LEVEL
)
2718 bytenr
= btrfs_node_blockptr(c
, slot
);
2720 free_extent_buffer(next
);
2722 next
= read_tree_block(root
, bytenr
,
2723 btrfs_level_size(root
, level
- 1));
2726 path
->slots
[level
] = slot
;
2729 c
= path
->nodes
[level
];
2730 free_extent_buffer(c
);
2731 slot
= btrfs_header_nritems(next
);
2734 path
->nodes
[level
] = next
;
2735 path
->slots
[level
] = slot
;
2738 next
= read_tree_block(root
, btrfs_node_blockptr(next
, slot
),
2739 btrfs_level_size(root
, level
- 1));
2745 * walk up the tree as far as required to find the next leaf.
2746 * returns 0 if it found something or 1 if there are no greater leaves.
2747 * returns < 0 on io errors.
2749 int btrfs_next_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2754 struct extent_buffer
*c
;
2755 struct extent_buffer
*next
= NULL
;
2757 while(level
< BTRFS_MAX_LEVEL
) {
2758 if (!path
->nodes
[level
])
2761 slot
= path
->slots
[level
] + 1;
2762 c
= path
->nodes
[level
];
2763 if (slot
>= btrfs_header_nritems(c
)) {
2765 if (level
== BTRFS_MAX_LEVEL
)
2770 bytenr
= btrfs_node_blockptr(c
, slot
);
2772 free_extent_buffer(next
);
2775 reada_for_search(root
, path
, level
, slot
, 0);
2777 next
= read_tree_block(root
, bytenr
,
2778 btrfs_level_size(root
, level
-1));
2781 path
->slots
[level
] = slot
;
2784 c
= path
->nodes
[level
];
2785 free_extent_buffer(c
);
2786 path
->nodes
[level
] = next
;
2787 path
->slots
[level
] = 0;
2791 reada_for_search(root
, path
, level
, 0, 0);
2792 next
= read_tree_block(root
, btrfs_node_blockptr(next
, 0),
2793 btrfs_level_size(root
, level
- 1));
2798 int btrfs_previous_item(struct btrfs_root
*root
,
2799 struct btrfs_path
*path
, u64 min_objectid
,
2802 struct btrfs_key found_key
;
2803 struct extent_buffer
*leaf
;
2807 if (path
->slots
[0] == 0) {
2808 ret
= btrfs_prev_leaf(root
, path
);
2814 leaf
= path
->nodes
[0];
2815 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
2816 if (found_key
.type
== type
)