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
;
161 WARN_ON(root
->ref_cows
&& trans
->transid
!=
162 root
->fs_info
->running_transaction
->transid
);
163 WARN_ON(root
->ref_cows
&& trans
->transid
!= root
->last_trans
);
165 level
= btrfs_header_level(buf
);
166 nritems
= btrfs_header_nritems(buf
);
169 btrfs_item_key_to_cpu(buf
, &first_key
, 0);
171 btrfs_node_key_to_cpu(buf
, &first_key
, 0);
173 first_key
.objectid
= 0;
175 cow
= __btrfs_alloc_free_block(trans
, root
, buf
->len
,
176 root
->root_key
.objectid
,
177 root_gen
, first_key
.objectid
, level
,
178 search_start
, empty_size
);
182 copy_extent_buffer(cow
, buf
, 0, 0, cow
->len
);
183 btrfs_set_header_bytenr(cow
, cow
->start
);
184 btrfs_set_header_generation(cow
, trans
->transid
);
185 btrfs_set_header_owner(cow
, root
->root_key
.objectid
);
186 btrfs_clear_header_flag(cow
, BTRFS_HEADER_FLAG_WRITTEN
);
188 WARN_ON(btrfs_header_generation(buf
) > trans
->transid
);
189 if (btrfs_header_generation(buf
) != trans
->transid
) {
191 ret
= btrfs_inc_ref(trans
, root
, buf
);
195 clean_tree_block(trans
, root
, buf
);
198 if (buf
== root
->node
) {
199 root_gen
= btrfs_header_generation(buf
);
201 extent_buffer_get(cow
);
202 if (buf
!= root
->commit_root
) {
203 btrfs_free_extent(trans
, root
, buf
->start
,
204 buf
->len
, root
->root_key
.objectid
,
207 free_extent_buffer(buf
);
208 add_root_to_dirty_list(root
);
210 root_gen
= btrfs_header_generation(parent
);
211 btrfs_set_node_blockptr(parent
, parent_slot
,
213 WARN_ON(trans
->transid
== 0);
214 btrfs_set_node_ptr_generation(parent
, parent_slot
,
216 btrfs_mark_buffer_dirty(parent
);
217 WARN_ON(btrfs_header_generation(parent
) != trans
->transid
);
218 btrfs_free_extent(trans
, root
, buf
->start
, buf
->len
,
219 btrfs_header_owner(parent
), root_gen
,
222 free_extent_buffer(buf
);
223 btrfs_mark_buffer_dirty(cow
);
228 int btrfs_cow_block(struct btrfs_trans_handle
*trans
,
229 struct btrfs_root
*root
, struct extent_buffer
*buf
,
230 struct extent_buffer
*parent
, int parent_slot
,
231 struct extent_buffer
**cow_ret
)
237 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
238 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
239 root
->fs_info
->running_transaction
->transid
);
242 if (trans
->transid
!= root
->fs_info
->generation
) {
243 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
244 root
->fs_info
->generation
);
248 header_trans
= btrfs_header_generation(buf
);
249 spin_lock(&root
->fs_info
->hash_lock
);
250 if (header_trans
== trans
->transid
&&
251 !btrfs_header_flag(buf
, BTRFS_HEADER_FLAG_WRITTEN
)) {
253 spin_unlock(&root
->fs_info
->hash_lock
);
256 spin_unlock(&root
->fs_info
->hash_lock
);
257 search_start
= buf
->start
& ~((u64
)(1024 * 1024 * 1024) - 1);
258 ret
= __btrfs_cow_block(trans
, root
, buf
, parent
,
259 parent_slot
, cow_ret
, search_start
, 0);
263 static int close_blocks(u64 blocknr
, u64 other
, u32 blocksize
)
265 if (blocknr
< other
&& other
- (blocknr
+ blocksize
) < 32768)
267 if (blocknr
> other
&& blocknr
- (other
+ blocksize
) < 32768)
273 * compare two keys in a memcmp fashion
275 static int comp_keys(struct btrfs_disk_key
*disk
, struct btrfs_key
*k2
)
279 btrfs_disk_key_to_cpu(&k1
, disk
);
281 if (k1
.objectid
> k2
->objectid
)
283 if (k1
.objectid
< k2
->objectid
)
285 if (k1
.type
> k2
->type
)
287 if (k1
.type
< k2
->type
)
289 if (k1
.offset
> k2
->offset
)
291 if (k1
.offset
< k2
->offset
)
297 int btrfs_realloc_node(struct btrfs_trans_handle
*trans
,
298 struct btrfs_root
*root
, struct extent_buffer
*parent
,
299 int start_slot
, int cache_only
, u64
*last_ret
,
300 struct btrfs_key
*progress
)
302 struct extent_buffer
*cur
;
303 struct extent_buffer
*tmp
;
305 u64 search_start
= *last_ret
;
315 int progress_passed
= 0;
316 struct btrfs_disk_key disk_key
;
318 parent_level
= btrfs_header_level(parent
);
319 if (cache_only
&& parent_level
!= 1)
322 if (trans
->transaction
!= root
->fs_info
->running_transaction
) {
323 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
324 root
->fs_info
->running_transaction
->transid
);
327 if (trans
->transid
!= root
->fs_info
->generation
) {
328 printk(KERN_CRIT
"trans %Lu running %Lu\n", trans
->transid
,
329 root
->fs_info
->generation
);
333 parent_nritems
= btrfs_header_nritems(parent
);
334 blocksize
= btrfs_level_size(root
, parent_level
- 1);
335 end_slot
= parent_nritems
;
337 if (parent_nritems
== 1)
340 for (i
= start_slot
; i
< end_slot
; i
++) {
343 if (!parent
->map_token
) {
344 map_extent_buffer(parent
,
345 btrfs_node_key_ptr_offset(i
),
346 sizeof(struct btrfs_key_ptr
),
347 &parent
->map_token
, &parent
->kaddr
,
348 &parent
->map_start
, &parent
->map_len
,
351 btrfs_node_key(parent
, &disk_key
, i
);
352 if (!progress_passed
&& comp_keys(&disk_key
, progress
) < 0)
356 blocknr
= btrfs_node_blockptr(parent
, i
);
358 last_block
= blocknr
;
361 other
= btrfs_node_blockptr(parent
, i
- 1);
362 close
= close_blocks(blocknr
, other
, blocksize
);
364 if (close
&& i
< end_slot
- 2) {
365 other
= btrfs_node_blockptr(parent
, i
+ 1);
366 close
= close_blocks(blocknr
, other
, blocksize
);
369 last_block
= blocknr
;
372 if (parent
->map_token
) {
373 unmap_extent_buffer(parent
, parent
->map_token
,
375 parent
->map_token
= NULL
;
378 cur
= btrfs_find_tree_block(root
, blocknr
, blocksize
);
380 uptodate
= btrfs_buffer_uptodate(cur
);
383 if (!cur
|| !uptodate
) {
385 free_extent_buffer(cur
);
389 cur
= read_tree_block(root
, blocknr
,
391 } else if (!uptodate
) {
392 btrfs_read_buffer(cur
);
395 if (search_start
== 0)
396 search_start
= last_block
;
398 btrfs_verify_block_csum(root
, cur
);
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 if (btrfs_header_level(path
->nodes
[level
]) != level
)
575 printk("warning: bad level %Lu wanted %d found %d\n",
576 path
->nodes
[level
]->start
, level
,
577 btrfs_header_level(path
->nodes
[level
]));
578 found_start
= btrfs_header_bytenr(path
->nodes
[level
]);
579 if (found_start
!= path
->nodes
[level
]->start
) {
580 printk("warning: bad bytentr %Lu found %Lu\n",
581 path
->nodes
[level
]->start
, found_start
);
584 struct extent_buffer
*buf
= path
->nodes
[level
];
586 if (memcmp_extent_buffer(buf
, root
->fs_info
->fsid
,
587 (unsigned long)btrfs_header_fsid(buf
),
589 printk("warning bad block %Lu\n", buf
->start
);
594 return check_leaf(root
, path
, level
);
595 return check_node(root
, path
, level
);
599 * search for key in the extent_buffer. The items start at offset p,
600 * and they are item_size apart. There are 'max' items in p.
602 * the slot in the array is returned via slot, and it points to
603 * the place where you would insert key if it is not found in
606 * slot may point to max if the key is bigger than all of the keys
608 static int generic_bin_search(struct extent_buffer
*eb
, unsigned long p
,
609 int item_size
, struct btrfs_key
*key
,
616 struct btrfs_disk_key
*tmp
= NULL
;
617 struct btrfs_disk_key unaligned
;
618 unsigned long offset
;
619 char *map_token
= NULL
;
621 unsigned long map_start
= 0;
622 unsigned long map_len
= 0;
626 mid
= (low
+ high
) / 2;
627 offset
= p
+ mid
* item_size
;
629 if (!map_token
|| offset
< map_start
||
630 (offset
+ sizeof(struct btrfs_disk_key
)) >
631 map_start
+ map_len
) {
633 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
636 err
= map_extent_buffer(eb
, offset
,
637 sizeof(struct btrfs_disk_key
),
639 &map_start
, &map_len
, KM_USER0
);
642 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
645 read_extent_buffer(eb
, &unaligned
,
646 offset
, sizeof(unaligned
));
651 tmp
= (struct btrfs_disk_key
*)(kaddr
+ offset
-
654 ret
= comp_keys(tmp
, key
);
663 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
669 unmap_extent_buffer(eb
, map_token
, KM_USER0
);
674 * simple bin_search frontend that does the right thing for
677 static int bin_search(struct extent_buffer
*eb
, struct btrfs_key
*key
,
678 int level
, int *slot
)
681 return generic_bin_search(eb
,
682 offsetof(struct btrfs_leaf
, items
),
683 sizeof(struct btrfs_item
),
684 key
, btrfs_header_nritems(eb
),
687 return generic_bin_search(eb
,
688 offsetof(struct btrfs_node
, ptrs
),
689 sizeof(struct btrfs_key_ptr
),
690 key
, btrfs_header_nritems(eb
),
696 static struct extent_buffer
*read_node_slot(struct btrfs_root
*root
,
697 struct extent_buffer
*parent
, int slot
)
701 if (slot
>= btrfs_header_nritems(parent
))
703 return read_tree_block(root
, btrfs_node_blockptr(parent
, slot
),
704 btrfs_level_size(root
, btrfs_header_level(parent
) - 1));
707 static int balance_level(struct btrfs_trans_handle
*trans
,
708 struct btrfs_root
*root
,
709 struct btrfs_path
*path
, int level
)
711 struct extent_buffer
*right
= NULL
;
712 struct extent_buffer
*mid
;
713 struct extent_buffer
*left
= NULL
;
714 struct extent_buffer
*parent
= NULL
;
718 int orig_slot
= path
->slots
[level
];
719 int err_on_enospc
= 0;
725 mid
= path
->nodes
[level
];
726 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
728 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
730 if (level
< BTRFS_MAX_LEVEL
- 1)
731 parent
= path
->nodes
[level
+ 1];
732 pslot
= path
->slots
[level
+ 1];
735 * deal with the case where there is only one pointer in the root
736 * by promoting the node below to a root
739 struct extent_buffer
*child
;
741 if (btrfs_header_nritems(mid
) != 1)
744 /* promote the child to a root */
745 child
= read_node_slot(root
, mid
, 0);
747 ret
= btrfs_cow_block(trans
, root
, child
, mid
, 0, &child
);
751 add_root_to_dirty_list(root
);
752 path
->nodes
[level
] = NULL
;
753 clean_tree_block(trans
, root
, mid
);
754 /* once for the path */
755 free_extent_buffer(mid
);
756 ret
= btrfs_free_extent(trans
, root
, mid
->start
, mid
->len
,
757 root
->root_key
.objectid
,
758 btrfs_header_generation(mid
), 0, 0, 1);
759 /* once for the root ptr */
760 free_extent_buffer(mid
);
763 if (btrfs_header_nritems(mid
) >
764 BTRFS_NODEPTRS_PER_BLOCK(root
) / 4)
767 if (btrfs_header_nritems(mid
) < 2)
770 left
= read_node_slot(root
, parent
, pslot
- 1);
772 wret
= btrfs_cow_block(trans
, root
, left
,
773 parent
, pslot
- 1, &left
);
779 right
= read_node_slot(root
, parent
, pslot
+ 1);
781 wret
= btrfs_cow_block(trans
, root
, right
,
782 parent
, pslot
+ 1, &right
);
789 /* first, try to make some room in the middle buffer */
791 orig_slot
+= btrfs_header_nritems(left
);
792 wret
= push_node_left(trans
, root
, left
, mid
);
795 if (btrfs_header_nritems(mid
) < 2)
800 * then try to empty the right most buffer into the middle
803 wret
= push_node_left(trans
, root
, mid
, right
);
804 if (wret
< 0 && wret
!= -ENOSPC
)
806 if (btrfs_header_nritems(right
) == 0) {
807 u64 bytenr
= right
->start
;
808 u64 generation
= btrfs_header_generation(parent
);
809 u32 blocksize
= right
->len
;
811 clean_tree_block(trans
, root
, right
);
812 free_extent_buffer(right
);
814 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
+
818 wret
= btrfs_free_extent(trans
, root
, bytenr
,
820 btrfs_header_owner(parent
),
821 generation
, 0, 0, 1);
825 struct btrfs_disk_key right_key
;
826 btrfs_node_key(right
, &right_key
, 0);
827 btrfs_set_node_key(parent
, &right_key
, pslot
+ 1);
828 btrfs_mark_buffer_dirty(parent
);
831 if (btrfs_header_nritems(mid
) == 1) {
833 * we're not allowed to leave a node with one item in the
834 * tree during a delete. A deletion from lower in the tree
835 * could try to delete the only pointer in this node.
836 * So, pull some keys from the left.
837 * There has to be a left pointer at this point because
838 * otherwise we would have pulled some pointers from the
842 wret
= balance_node_right(trans
, root
, mid
, left
);
849 if (btrfs_header_nritems(mid
) == 0) {
850 /* we've managed to empty the middle node, drop it */
851 u64 root_gen
= btrfs_header_generation(parent
);
852 u64 bytenr
= mid
->start
;
853 u32 blocksize
= mid
->len
;
854 clean_tree_block(trans
, root
, mid
);
855 free_extent_buffer(mid
);
857 wret
= del_ptr(trans
, root
, path
, level
+ 1, pslot
);
860 wret
= btrfs_free_extent(trans
, root
, bytenr
, blocksize
,
861 btrfs_header_owner(parent
),
866 /* update the parent key to reflect our changes */
867 struct btrfs_disk_key mid_key
;
868 btrfs_node_key(mid
, &mid_key
, 0);
869 btrfs_set_node_key(parent
, &mid_key
, pslot
);
870 btrfs_mark_buffer_dirty(parent
);
873 /* update the path */
875 if (btrfs_header_nritems(left
) > orig_slot
) {
876 extent_buffer_get(left
);
877 path
->nodes
[level
] = left
;
878 path
->slots
[level
+ 1] -= 1;
879 path
->slots
[level
] = orig_slot
;
881 free_extent_buffer(mid
);
883 orig_slot
-= btrfs_header_nritems(left
);
884 path
->slots
[level
] = orig_slot
;
887 /* double check we haven't messed things up */
888 check_block(root
, path
, level
);
890 btrfs_node_blockptr(path
->nodes
[level
], path
->slots
[level
]))
894 free_extent_buffer(right
);
896 free_extent_buffer(left
);
900 /* returns zero if the push worked, non-zero otherwise */
901 static int noinline
push_nodes_for_insert(struct btrfs_trans_handle
*trans
,
902 struct btrfs_root
*root
,
903 struct btrfs_path
*path
, int level
)
905 struct extent_buffer
*right
= NULL
;
906 struct extent_buffer
*mid
;
907 struct extent_buffer
*left
= NULL
;
908 struct extent_buffer
*parent
= NULL
;
912 int orig_slot
= path
->slots
[level
];
918 mid
= path
->nodes
[level
];
919 WARN_ON(btrfs_header_generation(mid
) != trans
->transid
);
920 orig_ptr
= btrfs_node_blockptr(mid
, orig_slot
);
922 if (level
< BTRFS_MAX_LEVEL
- 1)
923 parent
= path
->nodes
[level
+ 1];
924 pslot
= path
->slots
[level
+ 1];
929 left
= read_node_slot(root
, parent
, pslot
- 1);
931 /* first, try to make some room in the middle buffer */
934 left_nr
= btrfs_header_nritems(left
);
935 if (left_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
938 ret
= btrfs_cow_block(trans
, root
, left
, parent
,
943 wret
= push_node_left(trans
, root
,
950 struct btrfs_disk_key disk_key
;
951 orig_slot
+= left_nr
;
952 btrfs_node_key(mid
, &disk_key
, 0);
953 btrfs_set_node_key(parent
, &disk_key
, pslot
);
954 btrfs_mark_buffer_dirty(parent
);
955 if (btrfs_header_nritems(left
) > orig_slot
) {
956 path
->nodes
[level
] = left
;
957 path
->slots
[level
+ 1] -= 1;
958 path
->slots
[level
] = orig_slot
;
959 free_extent_buffer(mid
);
962 btrfs_header_nritems(left
);
963 path
->slots
[level
] = orig_slot
;
964 free_extent_buffer(left
);
968 free_extent_buffer(left
);
970 right
= read_node_slot(root
, parent
, pslot
+ 1);
973 * then try to empty the right most buffer into the middle
977 right_nr
= btrfs_header_nritems(right
);
978 if (right_nr
>= BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
981 ret
= btrfs_cow_block(trans
, root
, right
,
987 wret
= balance_node_right(trans
, root
,
994 struct btrfs_disk_key disk_key
;
996 btrfs_node_key(right
, &disk_key
, 0);
997 btrfs_set_node_key(parent
, &disk_key
, pslot
+ 1);
998 btrfs_mark_buffer_dirty(parent
);
1000 if (btrfs_header_nritems(mid
) <= orig_slot
) {
1001 path
->nodes
[level
] = right
;
1002 path
->slots
[level
+ 1] += 1;
1003 path
->slots
[level
] = orig_slot
-
1004 btrfs_header_nritems(mid
);
1005 free_extent_buffer(mid
);
1007 free_extent_buffer(right
);
1011 free_extent_buffer(right
);
1017 * readahead one full node of leaves
1019 static void reada_for_search(struct btrfs_root
*root
, struct btrfs_path
*path
,
1020 int level
, int slot
, u64 objectid
)
1022 struct extent_buffer
*node
;
1023 struct btrfs_disk_key disk_key
;
1029 int direction
= path
->reada
;
1030 struct extent_buffer
*eb
;
1038 if (!path
->nodes
[level
])
1041 node
= path
->nodes
[level
];
1042 search
= btrfs_node_blockptr(node
, slot
);
1043 blocksize
= btrfs_level_size(root
, level
- 1);
1044 eb
= btrfs_find_tree_block(root
, search
, blocksize
);
1046 free_extent_buffer(eb
);
1050 highest_read
= search
;
1051 lowest_read
= search
;
1053 nritems
= btrfs_header_nritems(node
);
1056 if (direction
< 0) {
1060 } else if (direction
> 0) {
1065 if (path
->reada
< 0 && objectid
) {
1066 btrfs_node_key(node
, &disk_key
, nr
);
1067 if (btrfs_disk_key_objectid(&disk_key
) != objectid
)
1070 search
= btrfs_node_blockptr(node
, nr
);
1071 if ((search
>= lowest_read
&& search
<= highest_read
) ||
1072 (search
< lowest_read
&& lowest_read
- search
<= 32768) ||
1073 (search
> highest_read
&& search
- highest_read
<= 32768)) {
1074 readahead_tree_block(root
, search
, blocksize
);
1078 if (path
->reada
< 2 && (nread
> (256 * 1024) || nscan
> 32))
1080 if(nread
> (1024 * 1024) || nscan
> 128)
1083 if (search
< lowest_read
)
1084 lowest_read
= search
;
1085 if (search
> highest_read
)
1086 highest_read
= search
;
1090 * look for key in the tree. path is filled in with nodes along the way
1091 * if key is found, we return zero and you can find the item in the leaf
1092 * level of the path (level 0)
1094 * If the key isn't found, the path points to the slot where it should
1095 * be inserted, and 1 is returned. If there are other errors during the
1096 * search a negative error number is returned.
1098 * if ins_len > 0, nodes and leaves will be split as we walk down the
1099 * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
1102 int btrfs_search_slot(struct btrfs_trans_handle
*trans
, struct btrfs_root
1103 *root
, struct btrfs_key
*key
, struct btrfs_path
*p
, int
1106 struct extent_buffer
*b
;
1112 int should_reada
= p
->reada
;
1113 u8 lowest_level
= 0;
1115 lowest_level
= p
->lowest_level
;
1116 WARN_ON(lowest_level
&& ins_len
);
1117 WARN_ON(p
->nodes
[0] != NULL
);
1118 WARN_ON(!mutex_is_locked(&root
->fs_info
->fs_mutex
));
1121 extent_buffer_get(b
);
1123 level
= btrfs_header_level(b
);
1126 wret
= btrfs_cow_block(trans
, root
, b
,
1127 p
->nodes
[level
+ 1],
1128 p
->slots
[level
+ 1],
1131 free_extent_buffer(b
);
1135 BUG_ON(!cow
&& ins_len
);
1136 if (level
!= btrfs_header_level(b
))
1138 level
= btrfs_header_level(b
);
1139 p
->nodes
[level
] = b
;
1140 ret
= check_block(root
, p
, level
);
1143 ret
= bin_search(b
, key
, level
, &slot
);
1145 if (ret
&& slot
> 0)
1147 p
->slots
[level
] = slot
;
1148 if (ins_len
> 0 && btrfs_header_nritems(b
) >=
1149 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1) {
1150 int sret
= split_node(trans
, root
, p
, level
);
1154 b
= p
->nodes
[level
];
1155 slot
= p
->slots
[level
];
1156 } else if (ins_len
< 0) {
1157 int sret
= balance_level(trans
, root
, p
,
1161 b
= p
->nodes
[level
];
1163 btrfs_release_path(NULL
, p
);
1166 slot
= p
->slots
[level
];
1167 BUG_ON(btrfs_header_nritems(b
) == 1);
1169 /* this is only true while dropping a snapshot */
1170 if (level
== lowest_level
)
1172 bytenr
= btrfs_node_blockptr(b
, slot
);
1173 ptr_gen
= btrfs_node_ptr_generation(b
, slot
);
1175 reada_for_search(root
, p
, level
, slot
,
1177 b
= read_tree_block(root
, bytenr
,
1178 btrfs_level_size(root
, level
- 1));
1179 if (ptr_gen
!= btrfs_header_generation(b
)) {
1180 printk("block %llu bad gen wanted %llu "
1182 (unsigned long long)b
->start
,
1183 (unsigned long long)ptr_gen
,
1184 (unsigned long long)btrfs_header_generation(b
));
1187 p
->slots
[level
] = slot
;
1188 if (ins_len
> 0 && btrfs_leaf_free_space(root
, b
) <
1189 sizeof(struct btrfs_item
) + ins_len
) {
1190 int sret
= split_leaf(trans
, root
, key
,
1191 p
, ins_len
, ret
== 0);
1203 * adjust the pointers going up the tree, starting at level
1204 * making sure the right key of each node is points to 'key'.
1205 * This is used after shifting pointers to the left, so it stops
1206 * fixing up pointers when a given leaf/node is not in slot 0 of the
1209 * If this fails to write a tree block, it returns -1, but continues
1210 * fixing up the blocks in ram so the tree is consistent.
1212 static int fixup_low_keys(struct btrfs_trans_handle
*trans
,
1213 struct btrfs_root
*root
, struct btrfs_path
*path
,
1214 struct btrfs_disk_key
*key
, int level
)
1218 struct extent_buffer
*t
;
1220 for (i
= level
; i
< BTRFS_MAX_LEVEL
; i
++) {
1221 int tslot
= path
->slots
[i
];
1222 if (!path
->nodes
[i
])
1225 btrfs_set_node_key(t
, key
, tslot
);
1226 btrfs_mark_buffer_dirty(path
->nodes
[i
]);
1234 * try to push data from one node into the next node left in the
1237 * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
1238 * error, and > 0 if there was no room in the left hand block.
1240 static int push_node_left(struct btrfs_trans_handle
*trans
,
1241 struct btrfs_root
*root
, struct extent_buffer
*dst
,
1242 struct extent_buffer
*src
)
1249 src_nritems
= btrfs_header_nritems(src
);
1250 dst_nritems
= btrfs_header_nritems(dst
);
1251 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1252 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1253 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1255 if (push_items
<= 0) {
1259 if (src_nritems
< push_items
)
1260 push_items
= src_nritems
;
1262 copy_extent_buffer(dst
, src
,
1263 btrfs_node_key_ptr_offset(dst_nritems
),
1264 btrfs_node_key_ptr_offset(0),
1265 push_items
* sizeof(struct btrfs_key_ptr
));
1267 if (push_items
< src_nritems
) {
1268 memmove_extent_buffer(src
, btrfs_node_key_ptr_offset(0),
1269 btrfs_node_key_ptr_offset(push_items
),
1270 (src_nritems
- push_items
) *
1271 sizeof(struct btrfs_key_ptr
));
1273 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1274 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1275 btrfs_mark_buffer_dirty(src
);
1276 btrfs_mark_buffer_dirty(dst
);
1281 * try to push data from one node into the next node right in the
1284 * returns 0 if some ptrs were pushed, < 0 if there was some horrible
1285 * error, and > 0 if there was no room in the right hand block.
1287 * this will only push up to 1/2 the contents of the left node over
1289 static int balance_node_right(struct btrfs_trans_handle
*trans
,
1290 struct btrfs_root
*root
,
1291 struct extent_buffer
*dst
,
1292 struct extent_buffer
*src
)
1300 WARN_ON(btrfs_header_generation(src
) != trans
->transid
);
1301 WARN_ON(btrfs_header_generation(dst
) != trans
->transid
);
1303 src_nritems
= btrfs_header_nritems(src
);
1304 dst_nritems
= btrfs_header_nritems(dst
);
1305 push_items
= BTRFS_NODEPTRS_PER_BLOCK(root
) - dst_nritems
;
1306 if (push_items
<= 0)
1309 max_push
= src_nritems
/ 2 + 1;
1310 /* don't try to empty the node */
1311 if (max_push
>= src_nritems
)
1314 if (max_push
< push_items
)
1315 push_items
= max_push
;
1317 memmove_extent_buffer(dst
, btrfs_node_key_ptr_offset(push_items
),
1318 btrfs_node_key_ptr_offset(0),
1320 sizeof(struct btrfs_key_ptr
));
1322 copy_extent_buffer(dst
, src
,
1323 btrfs_node_key_ptr_offset(0),
1324 btrfs_node_key_ptr_offset(src_nritems
- push_items
),
1325 push_items
* sizeof(struct btrfs_key_ptr
));
1327 btrfs_set_header_nritems(src
, src_nritems
- push_items
);
1328 btrfs_set_header_nritems(dst
, dst_nritems
+ push_items
);
1330 btrfs_mark_buffer_dirty(src
);
1331 btrfs_mark_buffer_dirty(dst
);
1336 * helper function to insert a new root level in the tree.
1337 * A new node is allocated, and a single item is inserted to
1338 * point to the existing root
1340 * returns zero on success or < 0 on failure.
1342 static int noinline
insert_new_root(struct btrfs_trans_handle
*trans
,
1343 struct btrfs_root
*root
,
1344 struct btrfs_path
*path
, int level
)
1348 struct extent_buffer
*lower
;
1349 struct extent_buffer
*c
;
1350 struct btrfs_disk_key lower_key
;
1352 BUG_ON(path
->nodes
[level
]);
1353 BUG_ON(path
->nodes
[level
-1] != root
->node
);
1356 root_gen
= trans
->transid
;
1360 lower
= path
->nodes
[level
-1];
1362 btrfs_item_key(lower
, &lower_key
, 0);
1364 btrfs_node_key(lower
, &lower_key
, 0);
1366 c
= __btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1367 root
->root_key
.objectid
,
1368 root_gen
, lower_key
.objectid
, level
,
1369 root
->node
->start
, 0);
1372 memset_extent_buffer(c
, 0, 0, root
->nodesize
);
1373 btrfs_set_header_nritems(c
, 1);
1374 btrfs_set_header_level(c
, level
);
1375 btrfs_set_header_bytenr(c
, c
->start
);
1376 btrfs_set_header_generation(c
, trans
->transid
);
1377 btrfs_set_header_owner(c
, root
->root_key
.objectid
);
1379 write_extent_buffer(c
, root
->fs_info
->fsid
,
1380 (unsigned long)btrfs_header_fsid(c
),
1383 write_extent_buffer(c
, root
->fs_info
->chunk_tree_uuid
,
1384 (unsigned long)btrfs_header_chunk_tree_uuid(c
),
1387 btrfs_set_node_key(c
, &lower_key
, 0);
1388 btrfs_set_node_blockptr(c
, 0, lower
->start
);
1389 lower_gen
= btrfs_header_generation(lower
);
1390 WARN_ON(lower_gen
== 0);
1392 btrfs_set_node_ptr_generation(c
, 0, lower_gen
);
1394 btrfs_mark_buffer_dirty(c
);
1396 /* the super has an extra ref to root->node */
1397 free_extent_buffer(root
->node
);
1399 add_root_to_dirty_list(root
);
1400 extent_buffer_get(c
);
1401 path
->nodes
[level
] = c
;
1402 path
->slots
[level
] = 0;
1404 if (root
->ref_cows
&& lower_gen
!= trans
->transid
) {
1405 struct btrfs_path
*back_path
= btrfs_alloc_path();
1407 ret
= btrfs_insert_extent_backref(trans
,
1408 root
->fs_info
->extent_root
,
1410 root
->root_key
.objectid
,
1411 trans
->transid
, 0, 0);
1413 btrfs_free_path(back_path
);
1419 * worker function to insert a single pointer in a node.
1420 * the node should have enough room for the pointer already
1422 * slot and level indicate where you want the key to go, and
1423 * blocknr is the block the key points to.
1425 * returns zero on success and < 0 on any error
1427 static int insert_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
1428 *root
, struct btrfs_path
*path
, struct btrfs_disk_key
1429 *key
, u64 bytenr
, int slot
, int level
)
1431 struct extent_buffer
*lower
;
1434 BUG_ON(!path
->nodes
[level
]);
1435 lower
= path
->nodes
[level
];
1436 nritems
= btrfs_header_nritems(lower
);
1439 if (nritems
== BTRFS_NODEPTRS_PER_BLOCK(root
))
1441 if (slot
!= nritems
) {
1442 memmove_extent_buffer(lower
,
1443 btrfs_node_key_ptr_offset(slot
+ 1),
1444 btrfs_node_key_ptr_offset(slot
),
1445 (nritems
- slot
) * sizeof(struct btrfs_key_ptr
));
1447 btrfs_set_node_key(lower
, key
, slot
);
1448 btrfs_set_node_blockptr(lower
, slot
, bytenr
);
1449 WARN_ON(trans
->transid
== 0);
1450 btrfs_set_node_ptr_generation(lower
, slot
, trans
->transid
);
1451 btrfs_set_header_nritems(lower
, nritems
+ 1);
1452 btrfs_mark_buffer_dirty(lower
);
1457 * split the node at the specified level in path in two.
1458 * The path is corrected to point to the appropriate node after the split
1460 * Before splitting this tries to make some room in the node by pushing
1461 * left and right, if either one works, it returns right away.
1463 * returns 0 on success and < 0 on failure
1465 static int split_node(struct btrfs_trans_handle
*trans
, struct btrfs_root
1466 *root
, struct btrfs_path
*path
, int level
)
1469 struct extent_buffer
*c
;
1470 struct extent_buffer
*split
;
1471 struct btrfs_disk_key disk_key
;
1477 c
= path
->nodes
[level
];
1478 WARN_ON(btrfs_header_generation(c
) != trans
->transid
);
1479 if (c
== root
->node
) {
1480 /* trying to split the root, lets make a new one */
1481 ret
= insert_new_root(trans
, root
, path
, level
+ 1);
1485 ret
= push_nodes_for_insert(trans
, root
, path
, level
);
1486 c
= path
->nodes
[level
];
1487 if (!ret
&& btrfs_header_nritems(c
) <
1488 BTRFS_NODEPTRS_PER_BLOCK(root
) - 1)
1494 c_nritems
= btrfs_header_nritems(c
);
1496 root_gen
= trans
->transid
;
1500 btrfs_node_key(c
, &disk_key
, 0);
1501 split
= __btrfs_alloc_free_block(trans
, root
, root
->nodesize
,
1502 root
->root_key
.objectid
,
1504 btrfs_disk_key_objectid(&disk_key
),
1505 level
, c
->start
, 0);
1507 return PTR_ERR(split
);
1509 btrfs_set_header_flags(split
, btrfs_header_flags(c
));
1510 btrfs_set_header_level(split
, btrfs_header_level(c
));
1511 btrfs_set_header_bytenr(split
, split
->start
);
1512 btrfs_set_header_generation(split
, trans
->transid
);
1513 btrfs_set_header_owner(split
, root
->root_key
.objectid
);
1514 btrfs_set_header_flags(split
, 0);
1515 write_extent_buffer(split
, root
->fs_info
->fsid
,
1516 (unsigned long)btrfs_header_fsid(split
),
1518 write_extent_buffer(split
, root
->fs_info
->chunk_tree_uuid
,
1519 (unsigned long)btrfs_header_chunk_tree_uuid(split
),
1522 mid
= (c_nritems
+ 1) / 2;
1524 copy_extent_buffer(split
, c
,
1525 btrfs_node_key_ptr_offset(0),
1526 btrfs_node_key_ptr_offset(mid
),
1527 (c_nritems
- mid
) * sizeof(struct btrfs_key_ptr
));
1528 btrfs_set_header_nritems(split
, c_nritems
- mid
);
1529 btrfs_set_header_nritems(c
, mid
);
1532 btrfs_mark_buffer_dirty(c
);
1533 btrfs_mark_buffer_dirty(split
);
1535 btrfs_node_key(split
, &disk_key
, 0);
1536 wret
= insert_ptr(trans
, root
, path
, &disk_key
, split
->start
,
1537 path
->slots
[level
+ 1] + 1,
1542 if (path
->slots
[level
] >= mid
) {
1543 path
->slots
[level
] -= mid
;
1544 free_extent_buffer(c
);
1545 path
->nodes
[level
] = split
;
1546 path
->slots
[level
+ 1] += 1;
1548 free_extent_buffer(split
);
1554 * how many bytes are required to store the items in a leaf. start
1555 * and nr indicate which items in the leaf to check. This totals up the
1556 * space used both by the item structs and the item data
1558 static int leaf_space_used(struct extent_buffer
*l
, int start
, int nr
)
1561 int nritems
= btrfs_header_nritems(l
);
1562 int end
= min(nritems
, start
+ nr
) - 1;
1566 data_len
= btrfs_item_end_nr(l
, start
);
1567 data_len
= data_len
- btrfs_item_offset_nr(l
, end
);
1568 data_len
+= sizeof(struct btrfs_item
) * nr
;
1569 WARN_ON(data_len
< 0);
1574 * The space between the end of the leaf items and
1575 * the start of the leaf data. IOW, how much room
1576 * the leaf has left for both items and data
1578 int btrfs_leaf_free_space(struct btrfs_root
*root
, struct extent_buffer
*leaf
)
1580 int nritems
= btrfs_header_nritems(leaf
);
1582 ret
= BTRFS_LEAF_DATA_SIZE(root
) - leaf_space_used(leaf
, 0, nritems
);
1584 printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
1585 ret
, (unsigned long) BTRFS_LEAF_DATA_SIZE(root
),
1586 leaf_space_used(leaf
, 0, nritems
), nritems
);
1592 * push some data in the path leaf to the right, trying to free up at
1593 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1595 * returns 1 if the push failed because the other node didn't have enough
1596 * room, 0 if everything worked out and < 0 if there were major errors.
1598 static int push_leaf_right(struct btrfs_trans_handle
*trans
, struct btrfs_root
1599 *root
, struct btrfs_path
*path
, int data_size
,
1602 struct extent_buffer
*left
= path
->nodes
[0];
1603 struct extent_buffer
*right
;
1604 struct extent_buffer
*upper
;
1605 struct btrfs_disk_key disk_key
;
1611 struct btrfs_item
*item
;
1619 slot
= path
->slots
[1];
1620 if (!path
->nodes
[1]) {
1623 upper
= path
->nodes
[1];
1624 if (slot
>= btrfs_header_nritems(upper
) - 1)
1627 right
= read_tree_block(root
, btrfs_node_blockptr(upper
, slot
+ 1),
1629 free_space
= btrfs_leaf_free_space(root
, right
);
1630 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1631 free_extent_buffer(right
);
1635 /* cow and double check */
1636 ret
= btrfs_cow_block(trans
, root
, right
, upper
,
1639 free_extent_buffer(right
);
1642 free_space
= btrfs_leaf_free_space(root
, right
);
1643 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1644 free_extent_buffer(right
);
1648 left_nritems
= btrfs_header_nritems(left
);
1649 if (left_nritems
== 0) {
1650 free_extent_buffer(right
);
1659 i
= left_nritems
- 1;
1661 item
= btrfs_item_nr(left
, i
);
1663 if (path
->slots
[0] == i
)
1664 push_space
+= data_size
+ sizeof(*item
);
1666 if (!left
->map_token
) {
1667 map_extent_buffer(left
, (unsigned long)item
,
1668 sizeof(struct btrfs_item
),
1669 &left
->map_token
, &left
->kaddr
,
1670 &left
->map_start
, &left
->map_len
,
1674 this_item_size
= btrfs_item_size(left
, item
);
1675 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1678 push_space
+= this_item_size
+ sizeof(*item
);
1683 if (left
->map_token
) {
1684 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1685 left
->map_token
= NULL
;
1688 if (push_items
== 0) {
1689 free_extent_buffer(right
);
1693 if (!empty
&& push_items
== left_nritems
)
1696 /* push left to right */
1697 right_nritems
= btrfs_header_nritems(right
);
1699 push_space
= btrfs_item_end_nr(left
, left_nritems
- push_items
);
1700 push_space
-= leaf_data_end(root
, left
);
1702 /* make room in the right data area */
1703 data_end
= leaf_data_end(root
, right
);
1704 memmove_extent_buffer(right
,
1705 btrfs_leaf_data(right
) + data_end
- push_space
,
1706 btrfs_leaf_data(right
) + data_end
,
1707 BTRFS_LEAF_DATA_SIZE(root
) - data_end
);
1709 /* copy from the left data area */
1710 copy_extent_buffer(right
, left
, btrfs_leaf_data(right
) +
1711 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1712 btrfs_leaf_data(left
) + leaf_data_end(root
, left
),
1715 memmove_extent_buffer(right
, btrfs_item_nr_offset(push_items
),
1716 btrfs_item_nr_offset(0),
1717 right_nritems
* sizeof(struct btrfs_item
));
1719 /* copy the items from left to right */
1720 copy_extent_buffer(right
, left
, btrfs_item_nr_offset(0),
1721 btrfs_item_nr_offset(left_nritems
- push_items
),
1722 push_items
* sizeof(struct btrfs_item
));
1724 /* update the item pointers */
1725 right_nritems
+= push_items
;
1726 btrfs_set_header_nritems(right
, right_nritems
);
1727 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1728 for (i
= 0; i
< right_nritems
; i
++) {
1729 item
= btrfs_item_nr(right
, i
);
1730 if (!right
->map_token
) {
1731 map_extent_buffer(right
, (unsigned long)item
,
1732 sizeof(struct btrfs_item
),
1733 &right
->map_token
, &right
->kaddr
,
1734 &right
->map_start
, &right
->map_len
,
1737 push_space
-= btrfs_item_size(right
, item
);
1738 btrfs_set_item_offset(right
, item
, push_space
);
1741 if (right
->map_token
) {
1742 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1743 right
->map_token
= NULL
;
1745 left_nritems
-= push_items
;
1746 btrfs_set_header_nritems(left
, left_nritems
);
1749 btrfs_mark_buffer_dirty(left
);
1750 btrfs_mark_buffer_dirty(right
);
1752 btrfs_item_key(right
, &disk_key
, 0);
1753 btrfs_set_node_key(upper
, &disk_key
, slot
+ 1);
1754 btrfs_mark_buffer_dirty(upper
);
1756 /* then fixup the leaf pointer in the path */
1757 if (path
->slots
[0] >= left_nritems
) {
1758 path
->slots
[0] -= left_nritems
;
1759 free_extent_buffer(path
->nodes
[0]);
1760 path
->nodes
[0] = right
;
1761 path
->slots
[1] += 1;
1763 free_extent_buffer(right
);
1768 * push some data in the path leaf to the left, trying to free up at
1769 * least data_size bytes. returns zero if the push worked, nonzero otherwise
1771 static int push_leaf_left(struct btrfs_trans_handle
*trans
, struct btrfs_root
1772 *root
, struct btrfs_path
*path
, int data_size
,
1775 struct btrfs_disk_key disk_key
;
1776 struct extent_buffer
*right
= path
->nodes
[0];
1777 struct extent_buffer
*left
;
1783 struct btrfs_item
*item
;
1784 u32 old_left_nritems
;
1790 u32 old_left_item_size
;
1792 slot
= path
->slots
[1];
1795 if (!path
->nodes
[1])
1798 right_nritems
= btrfs_header_nritems(right
);
1799 if (right_nritems
== 0) {
1803 left
= read_tree_block(root
, btrfs_node_blockptr(path
->nodes
[1],
1804 slot
- 1), root
->leafsize
);
1805 free_space
= btrfs_leaf_free_space(root
, left
);
1806 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1807 free_extent_buffer(left
);
1811 /* cow and double check */
1812 ret
= btrfs_cow_block(trans
, root
, left
,
1813 path
->nodes
[1], slot
- 1, &left
);
1815 /* we hit -ENOSPC, but it isn't fatal here */
1816 free_extent_buffer(left
);
1820 free_space
= btrfs_leaf_free_space(root
, left
);
1821 if (free_space
< data_size
+ sizeof(struct btrfs_item
)) {
1822 free_extent_buffer(left
);
1829 nr
= right_nritems
- 1;
1831 for (i
= 0; i
< nr
; i
++) {
1832 item
= btrfs_item_nr(right
, i
);
1833 if (!right
->map_token
) {
1834 map_extent_buffer(right
, (unsigned long)item
,
1835 sizeof(struct btrfs_item
),
1836 &right
->map_token
, &right
->kaddr
,
1837 &right
->map_start
, &right
->map_len
,
1841 if (path
->slots
[0] == i
)
1842 push_space
+= data_size
+ sizeof(*item
);
1844 this_item_size
= btrfs_item_size(right
, item
);
1845 if (this_item_size
+ sizeof(*item
) + push_space
> free_space
)
1849 push_space
+= this_item_size
+ sizeof(*item
);
1852 if (right
->map_token
) {
1853 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1854 right
->map_token
= NULL
;
1857 if (push_items
== 0) {
1858 free_extent_buffer(left
);
1861 if (!empty
&& push_items
== btrfs_header_nritems(right
))
1864 /* push data from right to left */
1865 copy_extent_buffer(left
, right
,
1866 btrfs_item_nr_offset(btrfs_header_nritems(left
)),
1867 btrfs_item_nr_offset(0),
1868 push_items
* sizeof(struct btrfs_item
));
1870 push_space
= BTRFS_LEAF_DATA_SIZE(root
) -
1871 btrfs_item_offset_nr(right
, push_items
-1);
1873 copy_extent_buffer(left
, right
, btrfs_leaf_data(left
) +
1874 leaf_data_end(root
, left
) - push_space
,
1875 btrfs_leaf_data(right
) +
1876 btrfs_item_offset_nr(right
, push_items
- 1),
1878 old_left_nritems
= btrfs_header_nritems(left
);
1879 BUG_ON(old_left_nritems
< 0);
1881 old_left_item_size
= btrfs_item_offset_nr(left
, old_left_nritems
- 1);
1882 for (i
= old_left_nritems
; i
< old_left_nritems
+ push_items
; i
++) {
1885 item
= btrfs_item_nr(left
, i
);
1886 if (!left
->map_token
) {
1887 map_extent_buffer(left
, (unsigned long)item
,
1888 sizeof(struct btrfs_item
),
1889 &left
->map_token
, &left
->kaddr
,
1890 &left
->map_start
, &left
->map_len
,
1894 ioff
= btrfs_item_offset(left
, item
);
1895 btrfs_set_item_offset(left
, item
,
1896 ioff
- (BTRFS_LEAF_DATA_SIZE(root
) - old_left_item_size
));
1898 btrfs_set_header_nritems(left
, old_left_nritems
+ push_items
);
1899 if (left
->map_token
) {
1900 unmap_extent_buffer(left
, left
->map_token
, KM_USER1
);
1901 left
->map_token
= NULL
;
1904 /* fixup right node */
1905 if (push_items
> right_nritems
) {
1906 printk("push items %d nr %u\n", push_items
, right_nritems
);
1910 if (push_items
< right_nritems
) {
1911 push_space
= btrfs_item_offset_nr(right
, push_items
- 1) -
1912 leaf_data_end(root
, right
);
1913 memmove_extent_buffer(right
, btrfs_leaf_data(right
) +
1914 BTRFS_LEAF_DATA_SIZE(root
) - push_space
,
1915 btrfs_leaf_data(right
) +
1916 leaf_data_end(root
, right
), push_space
);
1918 memmove_extent_buffer(right
, btrfs_item_nr_offset(0),
1919 btrfs_item_nr_offset(push_items
),
1920 (btrfs_header_nritems(right
) - push_items
) *
1921 sizeof(struct btrfs_item
));
1923 right_nritems
-= push_items
;
1924 btrfs_set_header_nritems(right
, right_nritems
);
1925 push_space
= BTRFS_LEAF_DATA_SIZE(root
);
1926 for (i
= 0; i
< right_nritems
; i
++) {
1927 item
= btrfs_item_nr(right
, i
);
1929 if (!right
->map_token
) {
1930 map_extent_buffer(right
, (unsigned long)item
,
1931 sizeof(struct btrfs_item
),
1932 &right
->map_token
, &right
->kaddr
,
1933 &right
->map_start
, &right
->map_len
,
1937 push_space
= push_space
- btrfs_item_size(right
, item
);
1938 btrfs_set_item_offset(right
, item
, push_space
);
1940 if (right
->map_token
) {
1941 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
1942 right
->map_token
= NULL
;
1945 btrfs_mark_buffer_dirty(left
);
1947 btrfs_mark_buffer_dirty(right
);
1949 btrfs_item_key(right
, &disk_key
, 0);
1950 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
1954 /* then fixup the leaf pointer in the path */
1955 if (path
->slots
[0] < push_items
) {
1956 path
->slots
[0] += old_left_nritems
;
1957 free_extent_buffer(path
->nodes
[0]);
1958 path
->nodes
[0] = left
;
1959 path
->slots
[1] -= 1;
1961 free_extent_buffer(left
);
1962 path
->slots
[0] -= push_items
;
1964 BUG_ON(path
->slots
[0] < 0);
1969 * split the path's leaf in two, making sure there is at least data_size
1970 * available for the resulting leaf level of the path.
1972 * returns 0 if all went well and < 0 on failure.
1974 static int split_leaf(struct btrfs_trans_handle
*trans
, struct btrfs_root
1975 *root
, struct btrfs_key
*ins_key
,
1976 struct btrfs_path
*path
, int data_size
, int extend
)
1979 struct extent_buffer
*l
;
1983 struct extent_buffer
*right
;
1984 int space_needed
= data_size
+ sizeof(struct btrfs_item
);
1991 int num_doubles
= 0;
1992 struct btrfs_disk_key disk_key
;
1995 space_needed
= data_size
;
1998 root_gen
= trans
->transid
;
2002 /* first try to make some room by pushing left and right */
2003 if (ins_key
->type
!= BTRFS_DIR_ITEM_KEY
) {
2004 wret
= push_leaf_right(trans
, root
, path
, data_size
, 0);
2009 wret
= push_leaf_left(trans
, root
, path
, data_size
, 0);
2015 /* did the pushes work? */
2016 if (btrfs_leaf_free_space(root
, l
) >= space_needed
)
2020 if (!path
->nodes
[1]) {
2021 ret
= insert_new_root(trans
, root
, path
, 1);
2028 slot
= path
->slots
[0];
2029 nritems
= btrfs_header_nritems(l
);
2030 mid
= (nritems
+ 1)/ 2;
2032 btrfs_item_key(l
, &disk_key
, 0);
2034 right
= __btrfs_alloc_free_block(trans
, root
, root
->leafsize
,
2035 root
->root_key
.objectid
,
2036 root_gen
, disk_key
.objectid
, 0,
2038 if (IS_ERR(right
)) {
2040 return PTR_ERR(right
);
2043 memset_extent_buffer(right
, 0, 0, sizeof(struct btrfs_header
));
2044 btrfs_set_header_bytenr(right
, right
->start
);
2045 btrfs_set_header_generation(right
, trans
->transid
);
2046 btrfs_set_header_owner(right
, root
->root_key
.objectid
);
2047 btrfs_set_header_level(right
, 0);
2048 write_extent_buffer(right
, root
->fs_info
->fsid
,
2049 (unsigned long)btrfs_header_fsid(right
),
2052 write_extent_buffer(right
, root
->fs_info
->chunk_tree_uuid
,
2053 (unsigned long)btrfs_header_chunk_tree_uuid(right
),
2057 leaf_space_used(l
, mid
, nritems
- mid
) + space_needed
>
2058 BTRFS_LEAF_DATA_SIZE(root
)) {
2059 if (slot
>= nritems
) {
2060 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2061 btrfs_set_header_nritems(right
, 0);
2062 wret
= insert_ptr(trans
, root
, path
,
2063 &disk_key
, right
->start
,
2064 path
->slots
[1] + 1, 1);
2067 free_extent_buffer(path
->nodes
[0]);
2068 path
->nodes
[0] = right
;
2070 path
->slots
[1] += 1;
2071 btrfs_mark_buffer_dirty(right
);
2075 if (mid
!= nritems
&&
2076 leaf_space_used(l
, mid
, nritems
- mid
) +
2077 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2082 if (leaf_space_used(l
, 0, mid
+ 1) + space_needed
>
2083 BTRFS_LEAF_DATA_SIZE(root
)) {
2084 if (!extend
&& slot
== 0) {
2085 btrfs_cpu_key_to_disk(&disk_key
, ins_key
);
2086 btrfs_set_header_nritems(right
, 0);
2087 wret
= insert_ptr(trans
, root
, path
,
2093 free_extent_buffer(path
->nodes
[0]);
2094 path
->nodes
[0] = right
;
2096 if (path
->slots
[1] == 0) {
2097 wret
= fixup_low_keys(trans
, root
,
2098 path
, &disk_key
, 1);
2102 btrfs_mark_buffer_dirty(right
);
2104 } else if (extend
&& slot
== 0) {
2108 if (mid
!= nritems
&&
2109 leaf_space_used(l
, mid
, nritems
- mid
) +
2110 space_needed
> BTRFS_LEAF_DATA_SIZE(root
)) {
2116 nritems
= nritems
- mid
;
2117 btrfs_set_header_nritems(right
, nritems
);
2118 data_copy_size
= btrfs_item_end_nr(l
, mid
) - leaf_data_end(root
, l
);
2120 copy_extent_buffer(right
, l
, btrfs_item_nr_offset(0),
2121 btrfs_item_nr_offset(mid
),
2122 nritems
* sizeof(struct btrfs_item
));
2124 copy_extent_buffer(right
, l
,
2125 btrfs_leaf_data(right
) + BTRFS_LEAF_DATA_SIZE(root
) -
2126 data_copy_size
, btrfs_leaf_data(l
) +
2127 leaf_data_end(root
, l
), data_copy_size
);
2129 rt_data_off
= BTRFS_LEAF_DATA_SIZE(root
) -
2130 btrfs_item_end_nr(l
, mid
);
2132 for (i
= 0; i
< nritems
; i
++) {
2133 struct btrfs_item
*item
= btrfs_item_nr(right
, i
);
2136 if (!right
->map_token
) {
2137 map_extent_buffer(right
, (unsigned long)item
,
2138 sizeof(struct btrfs_item
),
2139 &right
->map_token
, &right
->kaddr
,
2140 &right
->map_start
, &right
->map_len
,
2144 ioff
= btrfs_item_offset(right
, item
);
2145 btrfs_set_item_offset(right
, item
, ioff
+ rt_data_off
);
2148 if (right
->map_token
) {
2149 unmap_extent_buffer(right
, right
->map_token
, KM_USER1
);
2150 right
->map_token
= NULL
;
2153 btrfs_set_header_nritems(l
, mid
);
2155 btrfs_item_key(right
, &disk_key
, 0);
2156 wret
= insert_ptr(trans
, root
, path
, &disk_key
, right
->start
,
2157 path
->slots
[1] + 1, 1);
2161 btrfs_mark_buffer_dirty(right
);
2162 btrfs_mark_buffer_dirty(l
);
2163 BUG_ON(path
->slots
[0] != slot
);
2166 free_extent_buffer(path
->nodes
[0]);
2167 path
->nodes
[0] = right
;
2168 path
->slots
[0] -= mid
;
2169 path
->slots
[1] += 1;
2171 free_extent_buffer(right
);
2173 BUG_ON(path
->slots
[0] < 0);
2176 BUG_ON(num_doubles
!= 0);
2183 int btrfs_truncate_item(struct btrfs_trans_handle
*trans
,
2184 struct btrfs_root
*root
,
2185 struct btrfs_path
*path
,
2186 u32 new_size
, int from_end
)
2191 struct extent_buffer
*leaf
;
2192 struct btrfs_item
*item
;
2194 unsigned int data_end
;
2195 unsigned int old_data_start
;
2196 unsigned int old_size
;
2197 unsigned int size_diff
;
2200 slot_orig
= path
->slots
[0];
2201 leaf
= path
->nodes
[0];
2202 slot
= path
->slots
[0];
2204 old_size
= btrfs_item_size_nr(leaf
, slot
);
2205 if (old_size
== new_size
)
2208 nritems
= btrfs_header_nritems(leaf
);
2209 data_end
= leaf_data_end(root
, leaf
);
2211 old_data_start
= btrfs_item_offset_nr(leaf
, slot
);
2213 size_diff
= old_size
- new_size
;
2216 BUG_ON(slot
>= nritems
);
2219 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2221 /* first correct the data pointers */
2222 for (i
= slot
; i
< nritems
; i
++) {
2224 item
= btrfs_item_nr(leaf
, i
);
2226 if (!leaf
->map_token
) {
2227 map_extent_buffer(leaf
, (unsigned long)item
,
2228 sizeof(struct btrfs_item
),
2229 &leaf
->map_token
, &leaf
->kaddr
,
2230 &leaf
->map_start
, &leaf
->map_len
,
2234 ioff
= btrfs_item_offset(leaf
, item
);
2235 btrfs_set_item_offset(leaf
, item
, ioff
+ size_diff
);
2238 if (leaf
->map_token
) {
2239 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2240 leaf
->map_token
= NULL
;
2243 /* shift the data */
2245 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2246 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2247 data_end
, old_data_start
+ new_size
- data_end
);
2249 struct btrfs_disk_key disk_key
;
2252 btrfs_item_key(leaf
, &disk_key
, slot
);
2254 if (btrfs_disk_key_type(&disk_key
) == BTRFS_EXTENT_DATA_KEY
) {
2256 struct btrfs_file_extent_item
*fi
;
2258 fi
= btrfs_item_ptr(leaf
, slot
,
2259 struct btrfs_file_extent_item
);
2260 fi
= (struct btrfs_file_extent_item
*)(
2261 (unsigned long)fi
- size_diff
);
2263 if (btrfs_file_extent_type(leaf
, fi
) ==
2264 BTRFS_FILE_EXTENT_INLINE
) {
2265 ptr
= btrfs_item_ptr_offset(leaf
, slot
);
2266 memmove_extent_buffer(leaf
, ptr
,
2268 offsetof(struct btrfs_file_extent_item
,
2273 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2274 data_end
+ size_diff
, btrfs_leaf_data(leaf
) +
2275 data_end
, old_data_start
- data_end
);
2277 offset
= btrfs_disk_key_offset(&disk_key
);
2278 btrfs_set_disk_key_offset(&disk_key
, offset
+ size_diff
);
2279 btrfs_set_item_key(leaf
, &disk_key
, slot
);
2281 fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2284 item
= btrfs_item_nr(leaf
, slot
);
2285 btrfs_set_item_size(leaf
, item
, new_size
);
2286 btrfs_mark_buffer_dirty(leaf
);
2289 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2290 btrfs_print_leaf(root
, leaf
);
2296 int btrfs_extend_item(struct btrfs_trans_handle
*trans
,
2297 struct btrfs_root
*root
, struct btrfs_path
*path
,
2303 struct extent_buffer
*leaf
;
2304 struct btrfs_item
*item
;
2306 unsigned int data_end
;
2307 unsigned int old_data
;
2308 unsigned int old_size
;
2311 slot_orig
= path
->slots
[0];
2312 leaf
= path
->nodes
[0];
2314 nritems
= btrfs_header_nritems(leaf
);
2315 data_end
= leaf_data_end(root
, leaf
);
2317 if (btrfs_leaf_free_space(root
, leaf
) < data_size
) {
2318 btrfs_print_leaf(root
, leaf
);
2321 slot
= path
->slots
[0];
2322 old_data
= btrfs_item_end_nr(leaf
, slot
);
2325 if (slot
>= nritems
) {
2326 btrfs_print_leaf(root
, leaf
);
2327 printk("slot %d too large, nritems %d\n", slot
, nritems
);
2332 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2334 /* first correct the data pointers */
2335 for (i
= slot
; i
< nritems
; i
++) {
2337 item
= btrfs_item_nr(leaf
, i
);
2339 if (!leaf
->map_token
) {
2340 map_extent_buffer(leaf
, (unsigned long)item
,
2341 sizeof(struct btrfs_item
),
2342 &leaf
->map_token
, &leaf
->kaddr
,
2343 &leaf
->map_start
, &leaf
->map_len
,
2346 ioff
= btrfs_item_offset(leaf
, item
);
2347 btrfs_set_item_offset(leaf
, item
, ioff
- data_size
);
2350 if (leaf
->map_token
) {
2351 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2352 leaf
->map_token
= NULL
;
2355 /* shift the data */
2356 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2357 data_end
- data_size
, btrfs_leaf_data(leaf
) +
2358 data_end
, old_data
- data_end
);
2360 data_end
= old_data
;
2361 old_size
= btrfs_item_size_nr(leaf
, slot
);
2362 item
= btrfs_item_nr(leaf
, slot
);
2363 btrfs_set_item_size(leaf
, item
, old_size
+ data_size
);
2364 btrfs_mark_buffer_dirty(leaf
);
2367 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2368 btrfs_print_leaf(root
, leaf
);
2375 * Given a key and some data, insert an item into the tree.
2376 * This does all the path init required, making room in the tree if needed.
2378 int btrfs_insert_empty_items(struct btrfs_trans_handle
*trans
,
2379 struct btrfs_root
*root
,
2380 struct btrfs_path
*path
,
2381 struct btrfs_key
*cpu_key
, u32
*data_size
,
2384 struct extent_buffer
*leaf
;
2385 struct btrfs_item
*item
;
2393 unsigned int data_end
;
2394 struct btrfs_disk_key disk_key
;
2396 for (i
= 0; i
< nr
; i
++) {
2397 total_data
+= data_size
[i
];
2400 /* create a root if there isn't one */
2404 total_size
= total_data
+ (nr
- 1) * sizeof(struct btrfs_item
);
2405 ret
= btrfs_search_slot(trans
, root
, cpu_key
, path
, total_size
, 1);
2412 slot_orig
= path
->slots
[0];
2413 leaf
= path
->nodes
[0];
2415 nritems
= btrfs_header_nritems(leaf
);
2416 data_end
= leaf_data_end(root
, leaf
);
2418 if (btrfs_leaf_free_space(root
, leaf
) <
2419 sizeof(struct btrfs_item
) + total_size
) {
2420 btrfs_print_leaf(root
, leaf
);
2421 printk("not enough freespace need %u have %d\n",
2422 total_size
, btrfs_leaf_free_space(root
, leaf
));
2426 slot
= path
->slots
[0];
2429 if (slot
!= nritems
) {
2431 unsigned int old_data
= btrfs_item_end_nr(leaf
, slot
);
2433 if (old_data
< data_end
) {
2434 btrfs_print_leaf(root
, leaf
);
2435 printk("slot %d old_data %d data_end %d\n",
2436 slot
, old_data
, data_end
);
2440 * item0..itemN ... dataN.offset..dataN.size .. data0.size
2442 /* first correct the data pointers */
2443 WARN_ON(leaf
->map_token
);
2444 for (i
= slot
; i
< nritems
; i
++) {
2447 item
= btrfs_item_nr(leaf
, i
);
2448 if (!leaf
->map_token
) {
2449 map_extent_buffer(leaf
, (unsigned long)item
,
2450 sizeof(struct btrfs_item
),
2451 &leaf
->map_token
, &leaf
->kaddr
,
2452 &leaf
->map_start
, &leaf
->map_len
,
2456 ioff
= btrfs_item_offset(leaf
, item
);
2457 btrfs_set_item_offset(leaf
, item
, ioff
- total_data
);
2459 if (leaf
->map_token
) {
2460 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2461 leaf
->map_token
= NULL
;
2464 /* shift the items */
2465 memmove_extent_buffer(leaf
, btrfs_item_nr_offset(slot
+ nr
),
2466 btrfs_item_nr_offset(slot
),
2467 (nritems
- slot
) * sizeof(struct btrfs_item
));
2469 /* shift the data */
2470 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2471 data_end
- total_data
, btrfs_leaf_data(leaf
) +
2472 data_end
, old_data
- data_end
);
2473 data_end
= old_data
;
2476 /* setup the item for the new data */
2477 for (i
= 0; i
< nr
; i
++) {
2478 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
+ i
);
2479 btrfs_set_item_key(leaf
, &disk_key
, slot
+ i
);
2480 item
= btrfs_item_nr(leaf
, slot
+ i
);
2481 btrfs_set_item_offset(leaf
, item
, data_end
- data_size
[i
]);
2482 data_end
-= data_size
[i
];
2483 btrfs_set_item_size(leaf
, item
, data_size
[i
]);
2485 btrfs_set_header_nritems(leaf
, nritems
+ nr
);
2486 btrfs_mark_buffer_dirty(leaf
);
2490 btrfs_cpu_key_to_disk(&disk_key
, cpu_key
);
2491 ret
= fixup_low_keys(trans
, root
, path
, &disk_key
, 1);
2494 if (btrfs_leaf_free_space(root
, leaf
) < 0) {
2495 btrfs_print_leaf(root
, leaf
);
2504 * Given a key and some data, insert an item into the tree.
2505 * This does all the path init required, making room in the tree if needed.
2507 int btrfs_insert_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
2508 *root
, struct btrfs_key
*cpu_key
, void *data
, u32
2512 struct btrfs_path
*path
;
2513 struct extent_buffer
*leaf
;
2516 path
= btrfs_alloc_path();
2518 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
2520 leaf
= path
->nodes
[0];
2521 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
2522 write_extent_buffer(leaf
, data
, ptr
, data_size
);
2523 btrfs_mark_buffer_dirty(leaf
);
2525 btrfs_free_path(path
);
2530 * delete the pointer from a given node.
2532 * If the delete empties a node, the node is removed from the tree,
2533 * continuing all the way the root if required. The root is converted into
2534 * a leaf if all the nodes are emptied.
2536 static int del_ptr(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2537 struct btrfs_path
*path
, int level
, int slot
)
2539 struct extent_buffer
*parent
= path
->nodes
[level
];
2544 nritems
= btrfs_header_nritems(parent
);
2545 if (slot
!= nritems
-1) {
2546 memmove_extent_buffer(parent
,
2547 btrfs_node_key_ptr_offset(slot
),
2548 btrfs_node_key_ptr_offset(slot
+ 1),
2549 sizeof(struct btrfs_key_ptr
) *
2550 (nritems
- slot
- 1));
2553 btrfs_set_header_nritems(parent
, nritems
);
2554 if (nritems
== 0 && parent
== root
->node
) {
2555 BUG_ON(btrfs_header_level(root
->node
) != 1);
2556 /* just turn the root into a leaf and break */
2557 btrfs_set_header_level(root
->node
, 0);
2558 } else if (slot
== 0) {
2559 struct btrfs_disk_key disk_key
;
2561 btrfs_node_key(parent
, &disk_key
, 0);
2562 wret
= fixup_low_keys(trans
, root
, path
, &disk_key
, level
+ 1);
2566 btrfs_mark_buffer_dirty(parent
);
2571 * delete the item at the leaf level in path. If that empties
2572 * the leaf, remove it from the tree
2574 int btrfs_del_items(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
2575 struct btrfs_path
*path
, int slot
, int nr
)
2577 struct extent_buffer
*leaf
;
2578 struct btrfs_item
*item
;
2586 leaf
= path
->nodes
[0];
2587 last_off
= btrfs_item_offset_nr(leaf
, slot
+ nr
- 1);
2589 for (i
= 0; i
< nr
; i
++)
2590 dsize
+= btrfs_item_size_nr(leaf
, slot
+ i
);
2592 nritems
= btrfs_header_nritems(leaf
);
2594 if (slot
+ nr
!= nritems
) {
2596 int data_end
= leaf_data_end(root
, leaf
);
2598 memmove_extent_buffer(leaf
, btrfs_leaf_data(leaf
) +
2600 btrfs_leaf_data(leaf
) + data_end
,
2601 last_off
- data_end
);
2603 for (i
= slot
+ nr
; i
< nritems
; i
++) {
2606 item
= btrfs_item_nr(leaf
, i
);
2607 if (!leaf
->map_token
) {
2608 map_extent_buffer(leaf
, (unsigned long)item
,
2609 sizeof(struct btrfs_item
),
2610 &leaf
->map_token
, &leaf
->kaddr
,
2611 &leaf
->map_start
, &leaf
->map_len
,
2614 ioff
= btrfs_item_offset(leaf
, item
);
2615 btrfs_set_item_offset(leaf
, item
, ioff
+ dsize
);
2618 if (leaf
->map_token
) {
2619 unmap_extent_buffer(leaf
, leaf
->map_token
, KM_USER1
);
2620 leaf
->map_token
= NULL
;
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 wret
= del_ptr(trans
, root
, path
, 1, path
->slots
[1]);
2641 wret
= btrfs_free_extent(trans
, root
,
2642 leaf
->start
, leaf
->len
,
2643 btrfs_header_owner(path
->nodes
[1]),
2649 int used
= leaf_space_used(leaf
, 0, nritems
);
2651 struct btrfs_disk_key disk_key
;
2653 btrfs_item_key(leaf
, &disk_key
, 0);
2654 wret
= fixup_low_keys(trans
, root
, path
,
2660 /* delete the leaf if it is mostly empty */
2661 if (used
< BTRFS_LEAF_DATA_SIZE(root
) / 4) {
2662 /* push_leaf_left fixes the path.
2663 * make sure the path still points to our leaf
2664 * for possible call to del_ptr below
2666 slot
= path
->slots
[1];
2667 extent_buffer_get(leaf
);
2669 wret
= push_leaf_left(trans
, root
, path
, 1, 1);
2670 if (wret
< 0 && wret
!= -ENOSPC
)
2673 if (path
->nodes
[0] == leaf
&&
2674 btrfs_header_nritems(leaf
)) {
2675 wret
= push_leaf_right(trans
, root
, path
, 1, 1);
2676 if (wret
< 0 && wret
!= -ENOSPC
)
2680 if (btrfs_header_nritems(leaf
) == 0) {
2682 u64 bytenr
= leaf
->start
;
2683 u32 blocksize
= leaf
->len
;
2685 root_gen
= btrfs_header_generation(
2688 clean_tree_block(trans
, root
, leaf
);
2690 wret
= del_ptr(trans
, root
, path
, 1, slot
);
2694 free_extent_buffer(leaf
);
2695 wret
= btrfs_free_extent(trans
, root
, bytenr
,
2697 btrfs_header_owner(path
->nodes
[1]),
2702 btrfs_mark_buffer_dirty(leaf
);
2703 free_extent_buffer(leaf
);
2706 btrfs_mark_buffer_dirty(leaf
);
2713 * walk up the tree as far as required to find the previous leaf.
2714 * returns 0 if it found something or 1 if there are no lesser leaves.
2715 * returns < 0 on io errors.
2717 int btrfs_prev_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2722 struct extent_buffer
*c
;
2723 struct extent_buffer
*next
= NULL
;
2725 while(level
< BTRFS_MAX_LEVEL
) {
2726 if (!path
->nodes
[level
])
2729 slot
= path
->slots
[level
];
2730 c
= path
->nodes
[level
];
2733 if (level
== BTRFS_MAX_LEVEL
)
2739 bytenr
= btrfs_node_blockptr(c
, slot
);
2741 free_extent_buffer(next
);
2743 next
= read_tree_block(root
, bytenr
,
2744 btrfs_level_size(root
, level
- 1));
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_tree_block(root
, btrfs_node_blockptr(next
, slot
),
2760 btrfs_level_size(root
, level
- 1));
2766 * walk up the tree as far as required to find the next leaf.
2767 * returns 0 if it found something or 1 if there are no greater leaves.
2768 * returns < 0 on io errors.
2770 int btrfs_next_leaf(struct btrfs_root
*root
, struct btrfs_path
*path
)
2775 struct extent_buffer
*c
;
2776 struct extent_buffer
*next
= NULL
;
2778 while(level
< BTRFS_MAX_LEVEL
) {
2779 if (!path
->nodes
[level
])
2782 slot
= path
->slots
[level
] + 1;
2783 c
= path
->nodes
[level
];
2784 if (slot
>= btrfs_header_nritems(c
)) {
2786 if (level
== BTRFS_MAX_LEVEL
)
2791 bytenr
= btrfs_node_blockptr(c
, slot
);
2793 free_extent_buffer(next
);
2796 reada_for_search(root
, path
, level
, slot
, 0);
2798 next
= read_tree_block(root
, bytenr
,
2799 btrfs_level_size(root
, level
-1));
2802 path
->slots
[level
] = slot
;
2805 c
= path
->nodes
[level
];
2806 free_extent_buffer(c
);
2807 path
->nodes
[level
] = next
;
2808 path
->slots
[level
] = 0;
2812 reada_for_search(root
, path
, level
, 0, 0);
2813 next
= read_tree_block(root
, btrfs_node_blockptr(next
, 0),
2814 btrfs_level_size(root
, level
- 1));
2819 int btrfs_previous_item(struct btrfs_root
*root
,
2820 struct btrfs_path
*path
, u64 min_objectid
,
2823 struct btrfs_key found_key
;
2824 struct extent_buffer
*leaf
;
2828 if (path
->slots
[0] == 0) {
2829 ret
= btrfs_prev_leaf(root
, path
);
2835 leaf
= path
->nodes
[0];
2836 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
2837 if (found_key
.type
== type
)