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/bio.h>
20 #include <linux/slab.h>
21 #include <linux/pagemap.h>
22 #include <linux/highmem.h>
25 #include "transaction.h"
26 #include "print-tree.h"
28 #define MAX_CSUM_ITEMS(r, size) ((((BTRFS_LEAF_DATA_SIZE(r) - \
29 sizeof(struct btrfs_item) * 2) / \
32 #define MAX_ORDERED_SUM_BYTES(r) ((PAGE_SIZE - \
33 sizeof(struct btrfs_ordered_sum)) / \
34 sizeof(struct btrfs_sector_sum) * \
35 (r)->sectorsize - (r)->sectorsize)
37 int btrfs_insert_file_extent(struct btrfs_trans_handle
*trans
,
38 struct btrfs_root
*root
,
39 u64 objectid
, u64 pos
,
40 u64 disk_offset
, u64 disk_num_bytes
,
41 u64 num_bytes
, u64 offset
, u64 ram_bytes
,
42 u8 compression
, u8 encryption
, u16 other_encoding
)
45 struct btrfs_file_extent_item
*item
;
46 struct btrfs_key file_key
;
47 struct btrfs_path
*path
;
48 struct extent_buffer
*leaf
;
50 path
= btrfs_alloc_path();
53 file_key
.objectid
= objectid
;
54 file_key
.offset
= pos
;
55 btrfs_set_key_type(&file_key
, BTRFS_EXTENT_DATA_KEY
);
57 path
->leave_spinning
= 1;
58 ret
= btrfs_insert_empty_item(trans
, root
, path
, &file_key
,
63 leaf
= path
->nodes
[0];
64 item
= btrfs_item_ptr(leaf
, path
->slots
[0],
65 struct btrfs_file_extent_item
);
66 btrfs_set_file_extent_disk_bytenr(leaf
, item
, disk_offset
);
67 btrfs_set_file_extent_disk_num_bytes(leaf
, item
, disk_num_bytes
);
68 btrfs_set_file_extent_offset(leaf
, item
, offset
);
69 btrfs_set_file_extent_num_bytes(leaf
, item
, num_bytes
);
70 btrfs_set_file_extent_ram_bytes(leaf
, item
, ram_bytes
);
71 btrfs_set_file_extent_generation(leaf
, item
, trans
->transid
);
72 btrfs_set_file_extent_type(leaf
, item
, BTRFS_FILE_EXTENT_REG
);
73 btrfs_set_file_extent_compression(leaf
, item
, compression
);
74 btrfs_set_file_extent_encryption(leaf
, item
, encryption
);
75 btrfs_set_file_extent_other_encoding(leaf
, item
, other_encoding
);
77 btrfs_mark_buffer_dirty(leaf
);
79 btrfs_free_path(path
);
83 struct btrfs_csum_item
*btrfs_lookup_csum(struct btrfs_trans_handle
*trans
,
84 struct btrfs_root
*root
,
85 struct btrfs_path
*path
,
89 struct btrfs_key file_key
;
90 struct btrfs_key found_key
;
91 struct btrfs_csum_item
*item
;
92 struct extent_buffer
*leaf
;
95 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
98 file_key
.objectid
= BTRFS_EXTENT_CSUM_OBJECTID
;
99 file_key
.offset
= bytenr
;
100 btrfs_set_key_type(&file_key
, BTRFS_EXTENT_CSUM_KEY
);
101 ret
= btrfs_search_slot(trans
, root
, &file_key
, path
, 0, cow
);
104 leaf
= path
->nodes
[0];
107 if (path
->slots
[0] == 0)
110 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
111 if (btrfs_key_type(&found_key
) != BTRFS_EXTENT_CSUM_KEY
)
114 csum_offset
= (bytenr
- found_key
.offset
) >>
115 root
->fs_info
->sb
->s_blocksize_bits
;
116 csums_in_item
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
117 csums_in_item
/= csum_size
;
119 if (csum_offset
>= csums_in_item
) {
124 item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_csum_item
);
125 item
= (struct btrfs_csum_item
*)((unsigned char *)item
+
126 csum_offset
* csum_size
);
135 int btrfs_lookup_file_extent(struct btrfs_trans_handle
*trans
,
136 struct btrfs_root
*root
,
137 struct btrfs_path
*path
, u64 objectid
,
141 struct btrfs_key file_key
;
142 int ins_len
= mod
< 0 ? -1 : 0;
145 file_key
.objectid
= objectid
;
146 file_key
.offset
= offset
;
147 btrfs_set_key_type(&file_key
, BTRFS_EXTENT_DATA_KEY
);
148 ret
= btrfs_search_slot(trans
, root
, &file_key
, path
, ins_len
, cow
);
153 static int __btrfs_lookup_bio_sums(struct btrfs_root
*root
,
154 struct inode
*inode
, struct bio
*bio
,
155 u64 logical_offset
, u32
*dst
, int dio
)
158 struct bio_vec
*bvec
= bio
->bi_io_vec
;
161 u64 item_start_offset
= 0;
162 u64 item_last_offset
= 0;
166 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
168 struct btrfs_path
*path
;
169 struct btrfs_csum_item
*item
= NULL
;
170 struct extent_io_tree
*io_tree
= &BTRFS_I(inode
)->io_tree
;
172 path
= btrfs_alloc_path();
175 if (bio
->bi_size
> PAGE_CACHE_SIZE
* 8)
178 WARN_ON(bio
->bi_vcnt
<= 0);
180 disk_bytenr
= (u64
)bio
->bi_sector
<< 9;
182 offset
= logical_offset
;
183 while (bio_index
< bio
->bi_vcnt
) {
185 offset
= page_offset(bvec
->bv_page
) + bvec
->bv_offset
;
186 ret
= btrfs_find_ordered_sum(inode
, offset
, disk_bytenr
, &sum
);
190 if (!item
|| disk_bytenr
< item_start_offset
||
191 disk_bytenr
>= item_last_offset
) {
192 struct btrfs_key found_key
;
196 btrfs_release_path(root
, path
);
197 item
= btrfs_lookup_csum(NULL
, root
->fs_info
->csum_root
,
198 path
, disk_bytenr
, 0);
201 if (ret
== -ENOENT
|| ret
== -EFBIG
)
204 if (BTRFS_I(inode
)->root
->root_key
.objectid
==
205 BTRFS_DATA_RELOC_TREE_OBJECTID
) {
206 set_extent_bits(io_tree
, offset
,
207 offset
+ bvec
->bv_len
- 1,
208 EXTENT_NODATASUM
, GFP_NOFS
);
210 printk(KERN_INFO
"btrfs no csum found "
211 "for inode %llu start %llu\n",
214 (unsigned long long)offset
);
217 btrfs_release_path(root
, path
);
220 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
223 item_start_offset
= found_key
.offset
;
224 item_size
= btrfs_item_size_nr(path
->nodes
[0],
226 item_last_offset
= item_start_offset
+
227 (item_size
/ csum_size
) *
229 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
230 struct btrfs_csum_item
);
233 * this byte range must be able to fit inside
234 * a single leaf so it will also fit inside a u32
236 diff
= disk_bytenr
- item_start_offset
;
237 diff
= diff
/ root
->sectorsize
;
238 diff
= diff
* csum_size
;
240 read_extent_buffer(path
->nodes
[0], &sum
,
241 ((unsigned long)item
) + diff
,
247 set_state_private(io_tree
, offset
, sum
);
248 disk_bytenr
+= bvec
->bv_len
;
249 offset
+= bvec
->bv_len
;
253 btrfs_free_path(path
);
257 int btrfs_lookup_bio_sums(struct btrfs_root
*root
, struct inode
*inode
,
258 struct bio
*bio
, u32
*dst
)
260 return __btrfs_lookup_bio_sums(root
, inode
, bio
, 0, dst
, 0);
263 int btrfs_lookup_bio_sums_dio(struct btrfs_root
*root
, struct inode
*inode
,
264 struct bio
*bio
, u64 offset
, u32
*dst
)
266 return __btrfs_lookup_bio_sums(root
, inode
, bio
, offset
, dst
, 1);
269 int btrfs_lookup_csums_range(struct btrfs_root
*root
, u64 start
, u64 end
,
270 struct list_head
*list
)
272 struct btrfs_key key
;
273 struct btrfs_path
*path
;
274 struct extent_buffer
*leaf
;
275 struct btrfs_ordered_sum
*sums
;
276 struct btrfs_sector_sum
*sector_sum
;
277 struct btrfs_csum_item
*item
;
278 unsigned long offset
;
282 u16 csum_size
= btrfs_super_csum_size(&root
->fs_info
->super_copy
);
284 path
= btrfs_alloc_path();
287 key
.objectid
= BTRFS_EXTENT_CSUM_OBJECTID
;
289 key
.type
= BTRFS_EXTENT_CSUM_KEY
;
291 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
294 if (ret
> 0 && path
->slots
[0] > 0) {
295 leaf
= path
->nodes
[0];
296 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
297 if (key
.objectid
== BTRFS_EXTENT_CSUM_OBJECTID
&&
298 key
.type
== BTRFS_EXTENT_CSUM_KEY
) {
299 offset
= (start
- key
.offset
) >>
300 root
->fs_info
->sb
->s_blocksize_bits
;
301 if (offset
* csum_size
<
302 btrfs_item_size_nr(leaf
, path
->slots
[0] - 1))
307 while (start
<= end
) {
308 leaf
= path
->nodes
[0];
309 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
310 ret
= btrfs_next_leaf(root
, path
);
315 leaf
= path
->nodes
[0];
318 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
319 if (key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
320 key
.type
!= BTRFS_EXTENT_CSUM_KEY
)
323 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
324 if (key
.offset
> end
)
327 if (key
.offset
> start
)
330 size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
331 csum_end
= key
.offset
+ (size
/ csum_size
) * root
->sectorsize
;
332 if (csum_end
<= start
) {
337 csum_end
= min(csum_end
, end
+ 1);
338 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
339 struct btrfs_csum_item
);
340 while (start
< csum_end
) {
341 size
= min_t(size_t, csum_end
- start
,
342 MAX_ORDERED_SUM_BYTES(root
));
343 sums
= kzalloc(btrfs_ordered_sum_size(root
, size
),
347 sector_sum
= sums
->sums
;
348 sums
->bytenr
= start
;
351 offset
= (start
- key
.offset
) >>
352 root
->fs_info
->sb
->s_blocksize_bits
;
356 read_extent_buffer(path
->nodes
[0],
358 ((unsigned long)item
) +
360 sector_sum
->bytenr
= start
;
362 size
-= root
->sectorsize
;
363 start
+= root
->sectorsize
;
367 list_add_tail(&sums
->list
, list
);
373 btrfs_free_path(path
);
377 int btrfs_csum_one_bio(struct btrfs_root
*root
, struct inode
*inode
,
378 struct bio
*bio
, u64 file_start
, int contig
)
380 struct btrfs_ordered_sum
*sums
;
381 struct btrfs_sector_sum
*sector_sum
;
382 struct btrfs_ordered_extent
*ordered
;
384 struct bio_vec
*bvec
= bio
->bi_io_vec
;
386 unsigned long total_bytes
= 0;
387 unsigned long this_sum_bytes
= 0;
391 WARN_ON(bio
->bi_vcnt
<= 0);
392 sums
= kzalloc(btrfs_ordered_sum_size(root
, bio
->bi_size
), GFP_NOFS
);
396 sector_sum
= sums
->sums
;
397 disk_bytenr
= (u64
)bio
->bi_sector
<< 9;
398 sums
->len
= bio
->bi_size
;
399 INIT_LIST_HEAD(&sums
->list
);
404 offset
= page_offset(bvec
->bv_page
) + bvec
->bv_offset
;
406 ordered
= btrfs_lookup_ordered_extent(inode
, offset
);
408 sums
->bytenr
= ordered
->start
;
410 while (bio_index
< bio
->bi_vcnt
) {
412 offset
= page_offset(bvec
->bv_page
) + bvec
->bv_offset
;
414 if (!contig
&& (offset
>= ordered
->file_offset
+ ordered
->len
||
415 offset
< ordered
->file_offset
)) {
416 unsigned long bytes_left
;
417 sums
->len
= this_sum_bytes
;
419 btrfs_add_ordered_sum(inode
, ordered
, sums
);
420 btrfs_put_ordered_extent(ordered
);
422 bytes_left
= bio
->bi_size
- total_bytes
;
424 sums
= kzalloc(btrfs_ordered_sum_size(root
, bytes_left
),
427 sector_sum
= sums
->sums
;
428 sums
->len
= bytes_left
;
429 ordered
= btrfs_lookup_ordered_extent(inode
, offset
);
431 sums
->bytenr
= ordered
->start
;
434 data
= kmap_atomic(bvec
->bv_page
, KM_USER0
);
435 sector_sum
->sum
= ~(u32
)0;
436 sector_sum
->sum
= btrfs_csum_data(root
,
437 data
+ bvec
->bv_offset
,
440 kunmap_atomic(data
, KM_USER0
);
441 btrfs_csum_final(sector_sum
->sum
,
442 (char *)§or_sum
->sum
);
443 sector_sum
->bytenr
= disk_bytenr
;
447 total_bytes
+= bvec
->bv_len
;
448 this_sum_bytes
+= bvec
->bv_len
;
449 disk_bytenr
+= bvec
->bv_len
;
450 offset
+= bvec
->bv_len
;
454 btrfs_add_ordered_sum(inode
, ordered
, sums
);
455 btrfs_put_ordered_extent(ordered
);
460 * helper function for csum removal, this expects the
461 * key to describe the csum pointed to by the path, and it expects
462 * the csum to overlap the range [bytenr, len]
464 * The csum should not be entirely contained in the range and the
465 * range should not be entirely contained in the csum.
467 * This calls btrfs_truncate_item with the correct args based on the
468 * overlap, and fixes up the key as required.
470 static noinline
int truncate_one_csum(struct btrfs_trans_handle
*trans
,
471 struct btrfs_root
*root
,
472 struct btrfs_path
*path
,
473 struct btrfs_key
*key
,
476 struct extent_buffer
*leaf
;
478 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
480 u64 end_byte
= bytenr
+ len
;
481 u32 blocksize_bits
= root
->fs_info
->sb
->s_blocksize_bits
;
484 leaf
= path
->nodes
[0];
485 csum_end
= btrfs_item_size_nr(leaf
, path
->slots
[0]) / csum_size
;
486 csum_end
<<= root
->fs_info
->sb
->s_blocksize_bits
;
487 csum_end
+= key
->offset
;
489 if (key
->offset
< bytenr
&& csum_end
<= end_byte
) {
494 * A simple truncate off the end of the item
496 u32 new_size
= (bytenr
- key
->offset
) >> blocksize_bits
;
497 new_size
*= csum_size
;
498 ret
= btrfs_truncate_item(trans
, root
, path
, new_size
, 1);
500 } else if (key
->offset
>= bytenr
&& csum_end
> end_byte
&&
501 end_byte
> key
->offset
) {
506 * we need to truncate from the beginning of the csum
508 u32 new_size
= (csum_end
- end_byte
) >> blocksize_bits
;
509 new_size
*= csum_size
;
511 ret
= btrfs_truncate_item(trans
, root
, path
, new_size
, 0);
514 key
->offset
= end_byte
;
515 ret
= btrfs_set_item_key_safe(trans
, root
, path
, key
);
524 * deletes the csum items from the csum tree for a given
527 int btrfs_del_csums(struct btrfs_trans_handle
*trans
,
528 struct btrfs_root
*root
, u64 bytenr
, u64 len
)
530 struct btrfs_path
*path
;
531 struct btrfs_key key
;
532 u64 end_byte
= bytenr
+ len
;
534 struct extent_buffer
*leaf
;
537 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
538 int blocksize_bits
= root
->fs_info
->sb
->s_blocksize_bits
;
540 root
= root
->fs_info
->csum_root
;
542 path
= btrfs_alloc_path();
547 key
.objectid
= BTRFS_EXTENT_CSUM_OBJECTID
;
548 key
.offset
= end_byte
- 1;
549 key
.type
= BTRFS_EXTENT_CSUM_KEY
;
551 path
->leave_spinning
= 1;
552 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
554 if (path
->slots
[0] == 0)
557 } else if (ret
< 0) {
561 leaf
= path
->nodes
[0];
562 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
564 if (key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
565 key
.type
!= BTRFS_EXTENT_CSUM_KEY
) {
569 if (key
.offset
>= end_byte
)
572 csum_end
= btrfs_item_size_nr(leaf
, path
->slots
[0]) / csum_size
;
573 csum_end
<<= blocksize_bits
;
574 csum_end
+= key
.offset
;
576 /* this csum ends before we start, we're done */
577 if (csum_end
<= bytenr
)
580 /* delete the entire item, it is inside our range */
581 if (key
.offset
>= bytenr
&& csum_end
<= end_byte
) {
582 ret
= btrfs_del_item(trans
, root
, path
);
584 if (key
.offset
== bytenr
)
586 } else if (key
.offset
< bytenr
&& csum_end
> end_byte
) {
587 unsigned long offset
;
588 unsigned long shift_len
;
589 unsigned long item_offset
;
594 * Our bytes are in the middle of the csum,
595 * we need to split this item and insert a new one.
597 * But we can't drop the path because the
598 * csum could change, get removed, extended etc.
600 * The trick here is the max size of a csum item leaves
601 * enough room in the tree block for a single
602 * item header. So, we split the item in place,
603 * adding a new header pointing to the existing
604 * bytes. Then we loop around again and we have
605 * a nicely formed csum item that we can neatly
608 offset
= (bytenr
- key
.offset
) >> blocksize_bits
;
611 shift_len
= (len
>> blocksize_bits
) * csum_size
;
613 item_offset
= btrfs_item_ptr_offset(leaf
,
616 memset_extent_buffer(leaf
, 0, item_offset
+ offset
,
621 * btrfs_split_item returns -EAGAIN when the
622 * item changed size or key
624 ret
= btrfs_split_item(trans
, root
, path
, &key
, offset
);
625 BUG_ON(ret
&& ret
!= -EAGAIN
);
627 key
.offset
= end_byte
- 1;
629 ret
= truncate_one_csum(trans
, root
, path
,
632 if (key
.offset
< bytenr
)
635 btrfs_release_path(root
, path
);
638 btrfs_free_path(path
);
642 int btrfs_csum_file_blocks(struct btrfs_trans_handle
*trans
,
643 struct btrfs_root
*root
,
644 struct btrfs_ordered_sum
*sums
)
648 struct btrfs_key file_key
;
649 struct btrfs_key found_key
;
653 struct btrfs_path
*path
;
654 struct btrfs_csum_item
*item
;
655 struct btrfs_csum_item
*item_end
;
656 struct extent_buffer
*leaf
= NULL
;
658 struct btrfs_sector_sum
*sector_sum
;
663 unsigned long map_len
;
664 unsigned long map_start
;
666 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
668 path
= btrfs_alloc_path();
670 sector_sum
= sums
->sums
;
672 next_offset
= (u64
)-1;
674 file_key
.objectid
= BTRFS_EXTENT_CSUM_OBJECTID
;
675 file_key
.offset
= sector_sum
->bytenr
;
676 bytenr
= sector_sum
->bytenr
;
677 btrfs_set_key_type(&file_key
, BTRFS_EXTENT_CSUM_KEY
);
679 item
= btrfs_lookup_csum(trans
, root
, path
, sector_sum
->bytenr
, 1);
681 leaf
= path
->nodes
[0];
686 if (ret
!= -EFBIG
&& ret
!= -ENOENT
)
691 /* we found one, but it isn't big enough yet */
692 leaf
= path
->nodes
[0];
693 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
694 if ((item_size
/ csum_size
) >=
695 MAX_CSUM_ITEMS(root
, csum_size
)) {
696 /* already at max size, make a new one */
700 int slot
= path
->slots
[0] + 1;
701 /* we didn't find a csum item, insert one */
702 nritems
= btrfs_header_nritems(path
->nodes
[0]);
703 if (path
->slots
[0] >= nritems
- 1) {
704 ret
= btrfs_next_leaf(root
, path
);
711 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, slot
);
712 if (found_key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
713 found_key
.type
!= BTRFS_EXTENT_CSUM_KEY
) {
717 next_offset
= found_key
.offset
;
723 * at this point, we know the tree has an item, but it isn't big
724 * enough yet to put our csum in. Grow it
726 btrfs_release_path(root
, path
);
727 ret
= btrfs_search_slot(trans
, root
, &file_key
, path
,
733 if (path
->slots
[0] == 0)
738 leaf
= path
->nodes
[0];
739 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
740 csum_offset
= (bytenr
- found_key
.offset
) >>
741 root
->fs_info
->sb
->s_blocksize_bits
;
743 if (btrfs_key_type(&found_key
) != BTRFS_EXTENT_CSUM_KEY
||
744 found_key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
745 csum_offset
>= MAX_CSUM_ITEMS(root
, csum_size
)) {
749 if (csum_offset
>= btrfs_item_size_nr(leaf
, path
->slots
[0]) /
751 u32 diff
= (csum_offset
+ 1) * csum_size
;
754 * is the item big enough already? we dropped our lock
755 * before and need to recheck
757 if (diff
< btrfs_item_size_nr(leaf
, path
->slots
[0]))
760 diff
= diff
- btrfs_item_size_nr(leaf
, path
->slots
[0]);
761 if (diff
!= csum_size
)
764 ret
= btrfs_extend_item(trans
, root
, path
, diff
);
770 btrfs_release_path(root
, path
);
773 u64 tmp
= total_bytes
+ root
->sectorsize
;
774 u64 next_sector
= sector_sum
->bytenr
;
775 struct btrfs_sector_sum
*next
= sector_sum
+ 1;
777 while (tmp
< sums
->len
) {
778 if (next_sector
+ root
->sectorsize
!= next
->bytenr
)
780 tmp
+= root
->sectorsize
;
781 next_sector
= next
->bytenr
;
784 tmp
= min(tmp
, next_offset
- file_key
.offset
);
785 tmp
>>= root
->fs_info
->sb
->s_blocksize_bits
;
786 tmp
= max((u64
)1, tmp
);
787 tmp
= min(tmp
, (u64
)MAX_CSUM_ITEMS(root
, csum_size
));
788 ins_size
= csum_size
* tmp
;
790 ins_size
= csum_size
;
792 path
->leave_spinning
= 1;
793 ret
= btrfs_insert_empty_item(trans
, root
, path
, &file_key
,
795 path
->leave_spinning
= 0;
803 leaf
= path
->nodes
[0];
804 item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_csum_item
);
806 item
= (struct btrfs_csum_item
*)((unsigned char *)item
+
807 csum_offset
* csum_size
);
809 item_end
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_csum_item
);
810 item_end
= (struct btrfs_csum_item
*)((unsigned char *)item_end
+
811 btrfs_item_size_nr(leaf
, path
->slots
[0]));
816 (unsigned long)item
+ csum_size
>= map_start
+ map_len
) {
820 unmap_extent_buffer(leaf
, eb_token
, KM_USER1
);
822 err
= map_private_extent_buffer(leaf
, (unsigned long)item
,
825 &map_start
, &map_len
, KM_USER1
);
830 memcpy(eb_token
+ ((unsigned long)item
& (PAGE_CACHE_SIZE
- 1)),
831 §or_sum
->sum
, csum_size
);
833 write_extent_buffer(leaf
, §or_sum
->sum
,
834 (unsigned long)item
, csum_size
);
837 total_bytes
+= root
->sectorsize
;
839 if (total_bytes
< sums
->len
) {
840 item
= (struct btrfs_csum_item
*)((char *)item
+
842 if (item
< item_end
&& bytenr
+ PAGE_CACHE_SIZE
==
843 sector_sum
->bytenr
) {
844 bytenr
= sector_sum
->bytenr
;
849 unmap_extent_buffer(leaf
, eb_token
, KM_USER1
);
852 btrfs_mark_buffer_dirty(path
->nodes
[0]);
853 if (total_bytes
< sums
->len
) {
854 btrfs_release_path(root
, path
);
859 btrfs_free_path(path
);