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);
181 * the free space stuff is only read when it hasn't been
182 * updated in the current transaction. So, we can safely
183 * read from the commit root and sidestep a nasty deadlock
184 * between reading the free space cache and updating the csum tree.
186 if (btrfs_is_free_space_inode(root
, inode
))
187 path
->search_commit_root
= 1;
189 disk_bytenr
= (u64
)bio
->bi_sector
<< 9;
191 offset
= logical_offset
;
192 while (bio_index
< bio
->bi_vcnt
) {
194 offset
= page_offset(bvec
->bv_page
) + bvec
->bv_offset
;
195 ret
= btrfs_find_ordered_sum(inode
, offset
, disk_bytenr
, &sum
);
199 if (!item
|| disk_bytenr
< item_start_offset
||
200 disk_bytenr
>= item_last_offset
) {
201 struct btrfs_key found_key
;
205 btrfs_release_path(path
);
206 item
= btrfs_lookup_csum(NULL
, root
->fs_info
->csum_root
,
207 path
, disk_bytenr
, 0);
210 if (ret
== -ENOENT
|| ret
== -EFBIG
)
213 if (BTRFS_I(inode
)->root
->root_key
.objectid
==
214 BTRFS_DATA_RELOC_TREE_OBJECTID
) {
215 set_extent_bits(io_tree
, offset
,
216 offset
+ bvec
->bv_len
- 1,
217 EXTENT_NODATASUM
, GFP_NOFS
);
219 printk(KERN_INFO
"btrfs no csum found "
220 "for inode %llu start %llu\n",
223 (unsigned long long)offset
);
226 btrfs_release_path(path
);
229 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
232 item_start_offset
= found_key
.offset
;
233 item_size
= btrfs_item_size_nr(path
->nodes
[0],
235 item_last_offset
= item_start_offset
+
236 (item_size
/ csum_size
) *
238 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
239 struct btrfs_csum_item
);
242 * this byte range must be able to fit inside
243 * a single leaf so it will also fit inside a u32
245 diff
= disk_bytenr
- item_start_offset
;
246 diff
= diff
/ root
->sectorsize
;
247 diff
= diff
* csum_size
;
249 read_extent_buffer(path
->nodes
[0], &sum
,
250 ((unsigned long)item
) + diff
,
256 set_state_private(io_tree
, offset
, sum
);
257 disk_bytenr
+= bvec
->bv_len
;
258 offset
+= bvec
->bv_len
;
262 btrfs_free_path(path
);
266 int btrfs_lookup_bio_sums(struct btrfs_root
*root
, struct inode
*inode
,
267 struct bio
*bio
, u32
*dst
)
269 return __btrfs_lookup_bio_sums(root
, inode
, bio
, 0, dst
, 0);
272 int btrfs_lookup_bio_sums_dio(struct btrfs_root
*root
, struct inode
*inode
,
273 struct bio
*bio
, u64 offset
, u32
*dst
)
275 return __btrfs_lookup_bio_sums(root
, inode
, bio
, offset
, dst
, 1);
278 int btrfs_lookup_csums_range(struct btrfs_root
*root
, u64 start
, u64 end
,
279 struct list_head
*list
, int search_commit
)
281 struct btrfs_key key
;
282 struct btrfs_path
*path
;
283 struct extent_buffer
*leaf
;
284 struct btrfs_ordered_sum
*sums
;
285 struct btrfs_sector_sum
*sector_sum
;
286 struct btrfs_csum_item
*item
;
287 unsigned long offset
;
291 u16 csum_size
= btrfs_super_csum_size(&root
->fs_info
->super_copy
);
293 path
= btrfs_alloc_path();
297 path
->skip_locking
= 1;
299 path
->search_commit_root
= 1;
302 key
.objectid
= BTRFS_EXTENT_CSUM_OBJECTID
;
304 key
.type
= BTRFS_EXTENT_CSUM_KEY
;
306 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
309 if (ret
> 0 && path
->slots
[0] > 0) {
310 leaf
= path
->nodes
[0];
311 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
312 if (key
.objectid
== BTRFS_EXTENT_CSUM_OBJECTID
&&
313 key
.type
== BTRFS_EXTENT_CSUM_KEY
) {
314 offset
= (start
- key
.offset
) >>
315 root
->fs_info
->sb
->s_blocksize_bits
;
316 if (offset
* csum_size
<
317 btrfs_item_size_nr(leaf
, path
->slots
[0] - 1))
322 while (start
<= end
) {
323 leaf
= path
->nodes
[0];
324 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
325 ret
= btrfs_next_leaf(root
, path
);
330 leaf
= path
->nodes
[0];
333 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
334 if (key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
335 key
.type
!= BTRFS_EXTENT_CSUM_KEY
)
338 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
339 if (key
.offset
> end
)
342 if (key
.offset
> start
)
345 size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
346 csum_end
= key
.offset
+ (size
/ csum_size
) * root
->sectorsize
;
347 if (csum_end
<= start
) {
352 csum_end
= min(csum_end
, end
+ 1);
353 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
354 struct btrfs_csum_item
);
355 while (start
< csum_end
) {
356 size
= min_t(size_t, csum_end
- start
,
357 MAX_ORDERED_SUM_BYTES(root
));
358 sums
= kzalloc(btrfs_ordered_sum_size(root
, size
),
362 sector_sum
= sums
->sums
;
363 sums
->bytenr
= start
;
366 offset
= (start
- key
.offset
) >>
367 root
->fs_info
->sb
->s_blocksize_bits
;
371 read_extent_buffer(path
->nodes
[0],
373 ((unsigned long)item
) +
375 sector_sum
->bytenr
= start
;
377 size
-= root
->sectorsize
;
378 start
+= root
->sectorsize
;
382 list_add_tail(&sums
->list
, list
);
388 btrfs_free_path(path
);
392 int btrfs_csum_one_bio(struct btrfs_root
*root
, struct inode
*inode
,
393 struct bio
*bio
, u64 file_start
, int contig
)
395 struct btrfs_ordered_sum
*sums
;
396 struct btrfs_sector_sum
*sector_sum
;
397 struct btrfs_ordered_extent
*ordered
;
399 struct bio_vec
*bvec
= bio
->bi_io_vec
;
401 unsigned long total_bytes
= 0;
402 unsigned long this_sum_bytes
= 0;
406 WARN_ON(bio
->bi_vcnt
<= 0);
407 sums
= kzalloc(btrfs_ordered_sum_size(root
, bio
->bi_size
), GFP_NOFS
);
411 sector_sum
= sums
->sums
;
412 disk_bytenr
= (u64
)bio
->bi_sector
<< 9;
413 sums
->len
= bio
->bi_size
;
414 INIT_LIST_HEAD(&sums
->list
);
419 offset
= page_offset(bvec
->bv_page
) + bvec
->bv_offset
;
421 ordered
= btrfs_lookup_ordered_extent(inode
, offset
);
423 sums
->bytenr
= ordered
->start
;
425 while (bio_index
< bio
->bi_vcnt
) {
427 offset
= page_offset(bvec
->bv_page
) + bvec
->bv_offset
;
429 if (!contig
&& (offset
>= ordered
->file_offset
+ ordered
->len
||
430 offset
< ordered
->file_offset
)) {
431 unsigned long bytes_left
;
432 sums
->len
= this_sum_bytes
;
434 btrfs_add_ordered_sum(inode
, ordered
, sums
);
435 btrfs_put_ordered_extent(ordered
);
437 bytes_left
= bio
->bi_size
- total_bytes
;
439 sums
= kzalloc(btrfs_ordered_sum_size(root
, bytes_left
),
442 sector_sum
= sums
->sums
;
443 sums
->len
= bytes_left
;
444 ordered
= btrfs_lookup_ordered_extent(inode
, offset
);
446 sums
->bytenr
= ordered
->start
;
449 data
= kmap_atomic(bvec
->bv_page
, KM_USER0
);
450 sector_sum
->sum
= ~(u32
)0;
451 sector_sum
->sum
= btrfs_csum_data(root
,
452 data
+ bvec
->bv_offset
,
455 kunmap_atomic(data
, KM_USER0
);
456 btrfs_csum_final(sector_sum
->sum
,
457 (char *)§or_sum
->sum
);
458 sector_sum
->bytenr
= disk_bytenr
;
462 total_bytes
+= bvec
->bv_len
;
463 this_sum_bytes
+= bvec
->bv_len
;
464 disk_bytenr
+= bvec
->bv_len
;
465 offset
+= bvec
->bv_len
;
469 btrfs_add_ordered_sum(inode
, ordered
, sums
);
470 btrfs_put_ordered_extent(ordered
);
475 * helper function for csum removal, this expects the
476 * key to describe the csum pointed to by the path, and it expects
477 * the csum to overlap the range [bytenr, len]
479 * The csum should not be entirely contained in the range and the
480 * range should not be entirely contained in the csum.
482 * This calls btrfs_truncate_item with the correct args based on the
483 * overlap, and fixes up the key as required.
485 static noinline
int truncate_one_csum(struct btrfs_trans_handle
*trans
,
486 struct btrfs_root
*root
,
487 struct btrfs_path
*path
,
488 struct btrfs_key
*key
,
491 struct extent_buffer
*leaf
;
493 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
495 u64 end_byte
= bytenr
+ len
;
496 u32 blocksize_bits
= root
->fs_info
->sb
->s_blocksize_bits
;
499 leaf
= path
->nodes
[0];
500 csum_end
= btrfs_item_size_nr(leaf
, path
->slots
[0]) / csum_size
;
501 csum_end
<<= root
->fs_info
->sb
->s_blocksize_bits
;
502 csum_end
+= key
->offset
;
504 if (key
->offset
< bytenr
&& csum_end
<= end_byte
) {
509 * A simple truncate off the end of the item
511 u32 new_size
= (bytenr
- key
->offset
) >> blocksize_bits
;
512 new_size
*= csum_size
;
513 ret
= btrfs_truncate_item(trans
, root
, path
, new_size
, 1);
514 } else if (key
->offset
>= bytenr
&& csum_end
> end_byte
&&
515 end_byte
> key
->offset
) {
520 * we need to truncate from the beginning of the csum
522 u32 new_size
= (csum_end
- end_byte
) >> blocksize_bits
;
523 new_size
*= csum_size
;
525 ret
= btrfs_truncate_item(trans
, root
, path
, new_size
, 0);
527 key
->offset
= end_byte
;
528 ret
= btrfs_set_item_key_safe(trans
, root
, path
, key
);
537 * deletes the csum items from the csum tree for a given
540 int btrfs_del_csums(struct btrfs_trans_handle
*trans
,
541 struct btrfs_root
*root
, u64 bytenr
, u64 len
)
543 struct btrfs_path
*path
;
544 struct btrfs_key key
;
545 u64 end_byte
= bytenr
+ len
;
547 struct extent_buffer
*leaf
;
550 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
551 int blocksize_bits
= root
->fs_info
->sb
->s_blocksize_bits
;
553 root
= root
->fs_info
->csum_root
;
555 path
= btrfs_alloc_path();
560 key
.objectid
= BTRFS_EXTENT_CSUM_OBJECTID
;
561 key
.offset
= end_byte
- 1;
562 key
.type
= BTRFS_EXTENT_CSUM_KEY
;
564 path
->leave_spinning
= 1;
565 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
567 if (path
->slots
[0] == 0)
570 } else if (ret
< 0) {
574 leaf
= path
->nodes
[0];
575 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
577 if (key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
578 key
.type
!= BTRFS_EXTENT_CSUM_KEY
) {
582 if (key
.offset
>= end_byte
)
585 csum_end
= btrfs_item_size_nr(leaf
, path
->slots
[0]) / csum_size
;
586 csum_end
<<= blocksize_bits
;
587 csum_end
+= key
.offset
;
589 /* this csum ends before we start, we're done */
590 if (csum_end
<= bytenr
)
593 /* delete the entire item, it is inside our range */
594 if (key
.offset
>= bytenr
&& csum_end
<= end_byte
) {
595 ret
= btrfs_del_item(trans
, root
, path
);
598 if (key
.offset
== bytenr
)
600 } else if (key
.offset
< bytenr
&& csum_end
> end_byte
) {
601 unsigned long offset
;
602 unsigned long shift_len
;
603 unsigned long item_offset
;
608 * Our bytes are in the middle of the csum,
609 * we need to split this item and insert a new one.
611 * But we can't drop the path because the
612 * csum could change, get removed, extended etc.
614 * The trick here is the max size of a csum item leaves
615 * enough room in the tree block for a single
616 * item header. So, we split the item in place,
617 * adding a new header pointing to the existing
618 * bytes. Then we loop around again and we have
619 * a nicely formed csum item that we can neatly
622 offset
= (bytenr
- key
.offset
) >> blocksize_bits
;
625 shift_len
= (len
>> blocksize_bits
) * csum_size
;
627 item_offset
= btrfs_item_ptr_offset(leaf
,
630 memset_extent_buffer(leaf
, 0, item_offset
+ offset
,
635 * btrfs_split_item returns -EAGAIN when the
636 * item changed size or key
638 ret
= btrfs_split_item(trans
, root
, path
, &key
, offset
);
639 BUG_ON(ret
&& ret
!= -EAGAIN
);
641 key
.offset
= end_byte
- 1;
643 ret
= truncate_one_csum(trans
, root
, path
,
646 if (key
.offset
< bytenr
)
649 btrfs_release_path(path
);
653 btrfs_free_path(path
);
657 int btrfs_csum_file_blocks(struct btrfs_trans_handle
*trans
,
658 struct btrfs_root
*root
,
659 struct btrfs_ordered_sum
*sums
)
663 struct btrfs_key file_key
;
664 struct btrfs_key found_key
;
668 struct btrfs_path
*path
;
669 struct btrfs_csum_item
*item
;
670 struct btrfs_csum_item
*item_end
;
671 struct extent_buffer
*leaf
= NULL
;
673 struct btrfs_sector_sum
*sector_sum
;
677 btrfs_super_csum_size(&root
->fs_info
->super_copy
);
679 path
= btrfs_alloc_path();
681 sector_sum
= sums
->sums
;
683 next_offset
= (u64
)-1;
685 file_key
.objectid
= BTRFS_EXTENT_CSUM_OBJECTID
;
686 file_key
.offset
= sector_sum
->bytenr
;
687 bytenr
= sector_sum
->bytenr
;
688 btrfs_set_key_type(&file_key
, BTRFS_EXTENT_CSUM_KEY
);
690 item
= btrfs_lookup_csum(trans
, root
, path
, sector_sum
->bytenr
, 1);
692 leaf
= path
->nodes
[0];
697 if (ret
!= -EFBIG
&& ret
!= -ENOENT
)
702 /* we found one, but it isn't big enough yet */
703 leaf
= path
->nodes
[0];
704 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
705 if ((item_size
/ csum_size
) >=
706 MAX_CSUM_ITEMS(root
, csum_size
)) {
707 /* already at max size, make a new one */
711 int slot
= path
->slots
[0] + 1;
712 /* we didn't find a csum item, insert one */
713 nritems
= btrfs_header_nritems(path
->nodes
[0]);
714 if (path
->slots
[0] >= nritems
- 1) {
715 ret
= btrfs_next_leaf(root
, path
);
722 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, slot
);
723 if (found_key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
724 found_key
.type
!= BTRFS_EXTENT_CSUM_KEY
) {
728 next_offset
= found_key
.offset
;
734 * at this point, we know the tree has an item, but it isn't big
735 * enough yet to put our csum in. Grow it
737 btrfs_release_path(path
);
738 ret
= btrfs_search_slot(trans
, root
, &file_key
, path
,
744 if (path
->slots
[0] == 0)
749 leaf
= path
->nodes
[0];
750 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
751 csum_offset
= (bytenr
- found_key
.offset
) >>
752 root
->fs_info
->sb
->s_blocksize_bits
;
754 if (btrfs_key_type(&found_key
) != BTRFS_EXTENT_CSUM_KEY
||
755 found_key
.objectid
!= BTRFS_EXTENT_CSUM_OBJECTID
||
756 csum_offset
>= MAX_CSUM_ITEMS(root
, csum_size
)) {
760 if (csum_offset
>= btrfs_item_size_nr(leaf
, path
->slots
[0]) /
762 u32 diff
= (csum_offset
+ 1) * csum_size
;
765 * is the item big enough already? we dropped our lock
766 * before and need to recheck
768 if (diff
< btrfs_item_size_nr(leaf
, path
->slots
[0]))
771 diff
= diff
- btrfs_item_size_nr(leaf
, path
->slots
[0]);
772 if (diff
!= csum_size
)
775 ret
= btrfs_extend_item(trans
, root
, path
, diff
);
780 btrfs_release_path(path
);
783 u64 tmp
= total_bytes
+ root
->sectorsize
;
784 u64 next_sector
= sector_sum
->bytenr
;
785 struct btrfs_sector_sum
*next
= sector_sum
+ 1;
787 while (tmp
< sums
->len
) {
788 if (next_sector
+ root
->sectorsize
!= next
->bytenr
)
790 tmp
+= root
->sectorsize
;
791 next_sector
= next
->bytenr
;
794 tmp
= min(tmp
, next_offset
- file_key
.offset
);
795 tmp
>>= root
->fs_info
->sb
->s_blocksize_bits
;
796 tmp
= max((u64
)1, tmp
);
797 tmp
= min(tmp
, (u64
)MAX_CSUM_ITEMS(root
, csum_size
));
798 ins_size
= csum_size
* tmp
;
800 ins_size
= csum_size
;
802 path
->leave_spinning
= 1;
803 ret
= btrfs_insert_empty_item(trans
, root
, path
, &file_key
,
805 path
->leave_spinning
= 0;
813 leaf
= path
->nodes
[0];
814 item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_csum_item
);
816 item
= (struct btrfs_csum_item
*)((unsigned char *)item
+
817 csum_offset
* csum_size
);
819 item_end
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_csum_item
);
820 item_end
= (struct btrfs_csum_item
*)((unsigned char *)item_end
+
821 btrfs_item_size_nr(leaf
, path
->slots
[0]));
824 write_extent_buffer(leaf
, §or_sum
->sum
, (unsigned long)item
, csum_size
);
826 total_bytes
+= root
->sectorsize
;
828 if (total_bytes
< sums
->len
) {
829 item
= (struct btrfs_csum_item
*)((char *)item
+
831 if (item
< item_end
&& bytenr
+ PAGE_CACHE_SIZE
==
832 sector_sum
->bytenr
) {
833 bytenr
= sector_sum
->bytenr
;
838 btrfs_mark_buffer_dirty(path
->nodes
[0]);
839 if (total_bytes
< sums
->len
) {
840 btrfs_release_path(path
);
845 btrfs_free_path(path
);