-
Notifications
You must be signed in to change notification settings - Fork 0
/
file-item.c
1622 lines (1415 loc) · 44.7 KB
/
file-item.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*/
#include <linux/bio.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/sched/mm.h>
#include <linux/mm.h>
#include <crypto/hash.h>
#include "misc.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "volumes.h"
#include "print-tree.h"
#include "compression.h"
#include "apfs_trace.h"
#define __MAX_CSUM_ITEMS(r, size) ((unsigned long)(((APFS_LEAF_DATA_SIZE(r) - \
sizeof(struct apfs_item) * 2) / \
size) - 1))
#define MAX_CSUM_ITEMS(r, size) (min_t(u32, __MAX_CSUM_ITEMS(r, size), \
PAGE_SIZE))
/**
* Set inode's size according to filesystem options
*
* @inode: inode we want to update the disk_i_size for
* @new_i_size: i_size we want to set to, 0 if we use i_size
*
* With NO_HOLES set this simply sets the disk_is_size to whatever i_size_read()
* returns as it is perfectly fine with a file that has holes without hole file
* extent items.
*
* However without NO_HOLES we need to only return the area that is contiguous
* from the 0 offset of the file. Otherwise we could end up adjust i_size up
* to an extent that has a gap in between.
*
* Finally new_i_size should only be set in the case of truncate where we're not
* ready to use i_size_read() as the limiter yet.
*/
void apfs_inode_safe_disk_i_size_write(struct apfs_inode *inode, u64 new_i_size)
{
struct apfs_fs_info *fs_info = inode->root->fs_info;
u64 start, end, i_size;
int ret;
i_size = new_i_size ?: i_size_read(&inode->vfs_inode);
if (apfs_fs_incompat(fs_info, NO_HOLES)) {
inode->disk_i_size = i_size;
return;
}
spin_lock(&inode->lock);
ret = find_contiguous_extent_bit(&inode->file_extent_tree, 0, &start,
&end, EXTENT_DIRTY);
if (!ret && start == 0)
i_size = min(i_size, end + 1);
else
i_size = 0;
inode->disk_i_size = i_size;
spin_unlock(&inode->lock);
}
/**
* Mark range within a file as having a new extent inserted
*
* @inode: inode being modified
* @start: start file offset of the file extent we've inserted
* @len: logical length of the file extent item
*
* Call when we are inserting a new file extent where there was none before.
* Does not need to call this in the case where we're replacing an existing file
* extent, however if not sure it's fine to call this multiple times.
*
* The start and len must match the file extent item, so thus must be sectorsize
* aligned.
*/
int apfs_inode_set_file_extent_range(struct apfs_inode *inode, u64 start,
u64 len)
{
if (len == 0)
return 0;
ASSERT(IS_ALIGNED(start + len, inode->root->fs_info->sectorsize));
if (apfs_fs_incompat(inode->root->fs_info, NO_HOLES))
return 0;
return 0;
}
/**
* Marks an inode range as not having a backing extent
*
* @inode: inode being modified
* @start: start file offset of the file extent we've inserted
* @len: logical length of the file extent item
*
* Called when we drop a file extent, for example when we truncate. Doesn't
* need to be called for cases where we're replacing a file extent, like when
* we've COWed a file extent.
*
* The start and len must match the file extent item, so thus must be sectorsize
* aligned.
*/
int apfs_inode_clear_file_extent_range(struct apfs_inode *inode, u64 start,
u64 len)
{
if (len == 0)
return 0;
ASSERT(IS_ALIGNED(start + len, inode->root->fs_info->sectorsize) ||
len == (u64)-1);
if (apfs_fs_incompat(inode->root->fs_info, NO_HOLES))
return 0;
return clear_extent_bit(&inode->file_extent_tree, start,
start + len - 1, EXTENT_DIRTY, 0, 0, NULL);
}
static inline u32 max_ordered_sum_bytes(struct apfs_fs_info *fs_info,
u16 csum_size)
{
u32 ncsums = (PAGE_SIZE - sizeof(struct apfs_ordered_sum)) / csum_size;
return ncsums * fs_info->sectorsize;
}
int apfs_insert_file_extent(struct apfs_trans_handle *trans,
struct apfs_root *root,
u64 objectid, u64 pos,
u64 disk_offset, u64 disk_num_bytes,
u64 num_bytes, u64 offset, u64 ram_bytes,
u8 compression, u8 encryption, u16 other_encoding)
{
int ret = 0;
struct apfs_file_extent_item *item;
struct apfs_key file_key = {};
struct apfs_path *path;
struct extent_buffer *leaf;
path = apfs_alloc_path();
if (!path)
return -ENOMEM;
file_key.objectid = objectid;
file_key.offset = pos;
file_key.type = APFS_EXTENT_DATA_KEY;
ret = apfs_insert_empty_item(trans, root, path, &file_key,
sizeof(*item));
if (ret < 0)
goto out;
BUG_ON(ret); /* Can't happen */
leaf = path->nodes[0];
item = apfs_item_ptr(leaf, path->slots[0],
struct apfs_file_extent_item);
apfs_set_file_extent_disk_bytenr(leaf, item, disk_offset);
apfs_set_file_extent_disk_num_bytes(leaf, item, disk_num_bytes);
apfs_set_file_extent_offset(leaf, item, offset);
apfs_set_file_extent_num_bytes(leaf, item, num_bytes);
apfs_set_file_extent_ram_bytes(leaf, item, ram_bytes);
apfs_set_file_extent_generation(leaf, item, trans->transid);
apfs_set_file_extent_type(leaf, item, APFS_FILE_EXTENT_REG);
apfs_set_file_extent_compression(leaf, item, compression);
apfs_set_file_extent_encryption(leaf, item, encryption);
apfs_set_file_extent_other_encoding(leaf, item, other_encoding);
apfs_mark_buffer_dirty(leaf);
out:
apfs_free_path(path);
return ret;
}
static struct apfs_csum_item *
apfs_lookup_csum(struct apfs_trans_handle *trans,
struct apfs_root *root,
struct apfs_path *path,
u64 bytenr, int cow)
{
struct apfs_fs_info *fs_info = root->fs_info;
int ret;
struct apfs_key file_key = {};
struct apfs_key found_key = {};
struct apfs_csum_item *item;
struct extent_buffer *leaf;
u64 csum_offset = 0;
const u32 csum_size = fs_info->csum_size;
int csums_in_item;
file_key.objectid = APFS_EXTENT_CSUM_OBJECTID;
file_key.offset = bytenr;
file_key.type = APFS_EXTENT_CSUM_KEY;
ret = apfs_search_slot(trans, root, &file_key, path, 0, cow);
if (ret < 0)
goto fail;
leaf = path->nodes[0];
if (ret > 0) {
ret = 1;
if (path->slots[0] == 0)
goto fail;
path->slots[0]--;
apfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.type != APFS_EXTENT_CSUM_KEY)
goto fail;
csum_offset = (bytenr - found_key.offset) >>
fs_info->sectorsize_bits;
csums_in_item = apfs_item_size_nr(leaf, path->slots[0]);
csums_in_item /= csum_size;
if (csum_offset == csums_in_item) {
ret = -EFBIG;
goto fail;
} else if (csum_offset > csums_in_item) {
goto fail;
}
}
item = apfs_item_ptr(leaf, path->slots[0], struct apfs_csum_item);
item = (struct apfs_csum_item *)((unsigned char *)item +
csum_offset * csum_size);
return item;
fail:
if (ret > 0)
ret = -ENOENT;
return ERR_PTR(ret);
}
int apfs_lookup_file_extent(struct apfs_trans_handle *trans,
struct apfs_root *root,
struct apfs_path *path, u64 objectid,
u64 offset, int mod)
{
int ret;
struct apfs_key file_key = {};
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
file_key.oid = objectid;
file_key.offset = offset;
file_key.type = APFS_TYPE_FILE_EXTENT;
ret = apfs_search_slot(trans, root, &file_key, path, ins_len, cow);
trace_printk("search file extent objectid %llu oid %llu type %u offset %llu eb %llu slot %d ret %d\n",
file_key.objectid, file_key.oid, file_key.type, file_key.offset,
path->nodes[0]->start, path->slots[0], ret);
return ret;
}
/*
* Find checksums for logical bytenr range [disk_bytenr, disk_bytenr + len) and
* estore the result to @dst.
*
* Return >0 for the number of sectors we found.
* Return 0 for the range [disk_bytenr, disk_bytenr + sectorsize) has no csum
* for it. Caller may want to try next sector until one range is hit.
* Return <0 for fatal error.
*/
static int search_csum_tree(struct apfs_fs_info *fs_info,
struct apfs_path *path, u64 disk_bytenr,
u64 len, u8 *dst)
{
struct apfs_csum_item *item = NULL;
struct apfs_key key = {};
const u32 sectorsize = fs_info->sectorsize;
const u32 csum_size = fs_info->csum_size;
u32 itemsize;
int ret;
u64 csum_start;
u64 csum_len;
ASSERT(IS_ALIGNED(disk_bytenr, sectorsize) &&
IS_ALIGNED(len, sectorsize));
/* Check if the current csum item covers disk_bytenr */
if (path->nodes[0]) {
item = apfs_item_ptr(path->nodes[0], path->slots[0],
struct apfs_csum_item);
apfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
itemsize = apfs_item_size_nr(path->nodes[0], path->slots[0]);
csum_start = key.offset;
csum_len = (itemsize / csum_size) * sectorsize;
if (in_range(disk_bytenr, csum_start, csum_len))
goto found;
}
/* Current item doesn't contain the desired range, search again */
apfs_release_path(path);
item = apfs_lookup_csum(NULL, fs_info->csum_root, path, disk_bytenr, 0);
if (IS_ERR(item)) {
ret = PTR_ERR(item);
goto out;
}
apfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
itemsize = apfs_item_size_nr(path->nodes[0], path->slots[0]);
csum_start = key.offset;
csum_len = (itemsize / csum_size) * sectorsize;
ASSERT(in_range(disk_bytenr, csum_start, csum_len));
found:
ret = (min(csum_start + csum_len, disk_bytenr + len) -
disk_bytenr) >> fs_info->sectorsize_bits;
read_extent_buffer(path->nodes[0], dst, (unsigned long)item,
ret * csum_size);
out:
if (ret == -ENOENT)
ret = 0;
return ret;
}
/*
* Locate the file_offset of @cur_disk_bytenr of a @bio.
*
* Bio of apfs represents read range of
* [bi_sector << 9, bi_sector << 9 + bi_size).
* Knowing this, we can iterate through each bvec to locate the page belong to
* @cur_disk_bytenr and get the file offset.
*
* @inode is used to determine if the bvec page really belongs to @inode.
*
* Return 0 if we can't find the file offset
* Return >0 if we find the file offset and restore it to @file_offset_ret
*/
static int search_file_offset_in_bio(struct bio *bio, struct inode *inode,
u64 disk_bytenr, u64 *file_offset_ret)
{
struct bvec_iter iter;
struct bio_vec bvec;
u64 cur = bio->bi_iter.bi_sector << SECTOR_SHIFT;
int ret = 0;
bio_for_each_segment(bvec, bio, iter) {
struct page *page = bvec.bv_page;
if (cur > disk_bytenr)
break;
if (cur + bvec.bv_len <= disk_bytenr) {
cur += bvec.bv_len;
continue;
}
ASSERT(in_range(disk_bytenr, cur, bvec.bv_len));
if (page->mapping && page->mapping->host &&
page->mapping->host == inode) {
ret = 1;
*file_offset_ret = page_offset(page) + bvec.bv_offset +
disk_bytenr - cur;
break;
}
}
return ret;
}
/**
* Lookup the checksum for the read bio in csum tree.
*
* @inode: inode that the bio is for.
* @bio: bio to look up.
* @dst: Buffer of size nblocks * apfs_super_csum_size() used to return
* checksum (nblocks = bio->bi_iter.bi_size / fs_info->sectorsize). If
* NULL, the checksum buffer is allocated and returned in
* apfs_io_bio(bio)->csum instead.
*
* Return: BLK_STS_RESOURCE if allocating memory fails, BLK_STS_OK otherwise.
*/
blk_status_t apfs_lookup_bio_sums(struct inode *inode, struct bio *bio, u8 *dst)
{
struct apfs_fs_info *fs_info = apfs_sb(inode->i_sb);
struct extent_io_tree *io_tree = &APFS_I(inode)->io_tree;
struct apfs_path *path;
const u32 sectorsize = fs_info->sectorsize;
const u32 csum_size = fs_info->csum_size;
u32 orig_len = bio->bi_iter.bi_size;
u64 orig_disk_bytenr = bio->bi_iter.bi_sector << SECTOR_SHIFT;
u64 cur_disk_bytenr;
u8 *csum;
const unsigned int nblocks = orig_len >> fs_info->sectorsize_bits;
int count = 0;
if (!fs_info->csum_root || (APFS_I(inode)->flags & APFS_INODE_NODATASUM))
return BLK_STS_OK;
/*
* This function is only called for read bio.
*
* This means two things:
* - All our csums should only be in csum tree
* No ordered extents csums, as ordered extents are only for write
* path.
* - No need to bother any other info from bvec
* Since we're looking up csums, the only important info is the
* disk_bytenr and the length, which can be extracted from bi_iter
* directly.
*/
ASSERT(bio_op(bio) == REQ_OP_READ);
path = apfs_alloc_path();
if (!path)
return BLK_STS_RESOURCE;
if (!dst) {
struct apfs_io_bio *apfs_bio = apfs_io_bio(bio);
if (nblocks * csum_size > APFS_BIO_INLINE_CSUM_SIZE) {
apfs_bio->csum = kmalloc_array(nblocks, csum_size,
GFP_NOFS);
if (!apfs_bio->csum) {
apfs_free_path(path);
return BLK_STS_RESOURCE;
}
} else {
apfs_bio->csum = apfs_bio->csum_inline;
}
csum = apfs_bio->csum;
} else {
csum = dst;
}
/*
* If requested number of sectors is larger than one leaf can contain,
* kick the readahead for csum tree.
*/
if (nblocks > fs_info->csums_per_leaf)
path->reada = READA_FORWARD;
/*
* the free space stuff is only read when it hasn't been
* updated in the current transaction. So, we can safely
* read from the commit root and sidestep a nasty deadlock
* between reading the free space cache and updating the csum tree.
*/
if (apfs_is_free_space_inode(APFS_I(inode))) {
path->search_commit_root = 1;
path->skip_locking = 1;
}
for (cur_disk_bytenr = orig_disk_bytenr;
cur_disk_bytenr < orig_disk_bytenr + orig_len;
cur_disk_bytenr += (count * sectorsize)) {
u64 search_len = orig_disk_bytenr + orig_len - cur_disk_bytenr;
unsigned int sector_offset;
u8 *csum_dst;
/*
* Although both cur_disk_bytenr and orig_disk_bytenr is u64,
* we're calculating the offset to the bio start.
*
* Bio size is limited to UINT_MAX, thus unsigned int is large
* enough to contain the raw result, not to mention the right
* shifted result.
*/
ASSERT(cur_disk_bytenr - orig_disk_bytenr < UINT_MAX);
sector_offset = (cur_disk_bytenr - orig_disk_bytenr) >>
fs_info->sectorsize_bits;
csum_dst = csum + sector_offset * csum_size;
count = search_csum_tree(fs_info, path, cur_disk_bytenr,
search_len, csum_dst);
if (count <= 0) {
/*
* Either we hit a critical error or we didn't find
* the csum.
* Either way, we put zero into the csums dst, and skip
* to the next sector.
*/
memset(csum_dst, 0, csum_size);
count = 1;
/*
* For data reloc inode, we need to mark the range
* NODATASUM so that balance won't report false csum
* error.
*/
if (APFS_I(inode)->root->root_key.objectid ==
APFS_DATA_RELOC_TREE_OBJECTID) {
u64 file_offset;
int ret;
ret = search_file_offset_in_bio(bio, inode,
cur_disk_bytenr, &file_offset);
if (ret)
set_extent_bits(io_tree, file_offset,
file_offset + sectorsize - 1,
EXTENT_NODATASUM);
} else {
apfs_warn_rl(fs_info,
"csum hole found for disk bytenr range [%llu, %llu)",
cur_disk_bytenr, cur_disk_bytenr + sectorsize);
}
}
}
apfs_free_path(path);
return BLK_STS_OK;
}
int apfs_lookup_csums_range(struct apfs_root *root, u64 start, u64 end,
struct list_head *list, int search_commit)
{
struct apfs_fs_info *fs_info = root->fs_info;
struct apfs_key key = {};
struct apfs_path *path;
struct extent_buffer *leaf;
struct apfs_ordered_sum *sums;
struct apfs_csum_item *item;
LIST_HEAD(tmplist);
unsigned long offset;
int ret;
size_t size;
u64 csum_end;
const u32 csum_size = fs_info->csum_size;
ASSERT(IS_ALIGNED(start, fs_info->sectorsize) &&
IS_ALIGNED(end + 1, fs_info->sectorsize));
path = apfs_alloc_path();
if (!path)
return -ENOMEM;
if (search_commit) {
path->skip_locking = 1;
path->reada = READA_FORWARD;
path->search_commit_root = 1;
}
key.objectid = APFS_EXTENT_CSUM_OBJECTID;
key.offset = start;
key.type = APFS_EXTENT_CSUM_KEY;
ret = apfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto fail;
if (ret > 0 && path->slots[0] > 0) {
leaf = path->nodes[0];
apfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
if (key.objectid == APFS_EXTENT_CSUM_OBJECTID &&
key.type == APFS_EXTENT_CSUM_KEY) {
offset = (start - key.offset) >> fs_info->sectorsize_bits;
if (offset * csum_size <
apfs_item_size_nr(leaf, path->slots[0] - 1))
path->slots[0]--;
}
}
while (start <= end) {
leaf = path->nodes[0];
if (path->slots[0] >= apfs_header_nritems(leaf)) {
ret = apfs_next_leaf(root, path);
if (ret < 0)
goto fail;
if (ret > 0)
break;
leaf = path->nodes[0];
}
apfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.objectid != APFS_EXTENT_CSUM_OBJECTID ||
key.type != APFS_EXTENT_CSUM_KEY ||
key.offset > end)
break;
if (key.offset > start)
start = key.offset;
size = apfs_item_size_nr(leaf, path->slots[0]);
csum_end = key.offset + (size / csum_size) * fs_info->sectorsize;
if (csum_end <= start) {
path->slots[0]++;
continue;
}
csum_end = min(csum_end, end + 1);
item = apfs_item_ptr(path->nodes[0], path->slots[0],
struct apfs_csum_item);
while (start < csum_end) {
size = min_t(size_t, csum_end - start,
max_ordered_sum_bytes(fs_info, csum_size));
sums = kzalloc(apfs_ordered_sum_size(fs_info, size),
GFP_NOFS);
if (!sums) {
ret = -ENOMEM;
goto fail;
}
sums->bytenr = start;
sums->len = (int)size;
offset = (start - key.offset) >> fs_info->sectorsize_bits;
offset *= csum_size;
size >>= fs_info->sectorsize_bits;
read_extent_buffer(path->nodes[0],
sums->sums,
((unsigned long)item) + offset,
csum_size * size);
start += fs_info->sectorsize * size;
list_add_tail(&sums->list, &tmplist);
}
path->slots[0]++;
}
ret = 0;
fail:
while (ret < 0 && !list_empty(&tmplist)) {
sums = list_entry(tmplist.next, struct apfs_ordered_sum, list);
list_del(&sums->list);
kfree(sums);
}
list_splice_tail(&tmplist, list);
apfs_free_path(path);
return ret;
}
/*
* apfs_csum_one_bio - Calculates checksums of the data contained inside a bio
* @inode: Owner of the data inside the bio
* @bio: Contains the data to be checksummed
* @file_start: offset in file this bio begins to describe
* @contig: Boolean. If true/1 means all bio vecs in this bio are
* contiguous and they begin at @file_start in the file. False/0
* means this bio can contain potentially discontiguous bio vecs
* so the logical offset of each should be calculated separately.
*/
blk_status_t apfs_csum_one_bio(struct apfs_inode *inode, struct bio *bio,
u64 file_start, int contig)
{
struct apfs_fs_info *fs_info = inode->root->fs_info;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
struct apfs_ordered_sum *sums;
struct apfs_ordered_extent *ordered = NULL;
char *data;
struct bvec_iter iter;
struct bio_vec bvec;
int index;
int nr_sectors;
unsigned long total_bytes = 0;
unsigned long this_sum_bytes = 0;
int i;
u64 offset;
unsigned nofs_flag;
nofs_flag = memalloc_nofs_save();
sums = kvzalloc(apfs_ordered_sum_size(fs_info, bio->bi_iter.bi_size),
GFP_KERNEL);
memalloc_nofs_restore(nofs_flag);
if (!sums)
return BLK_STS_RESOURCE;
sums->len = bio->bi_iter.bi_size;
INIT_LIST_HEAD(&sums->list);
if (contig)
offset = file_start;
else
offset = 0; /* shut up gcc */
sums->bytenr = bio->bi_iter.bi_sector << 9;
index = 0;
shash->tfm = fs_info->csum_shash;
bio_for_each_segment(bvec, bio, iter) {
if (!contig)
offset = page_offset(bvec.bv_page) + bvec.bv_offset;
if (!ordered) {
ordered = apfs_lookup_ordered_extent(inode, offset);
BUG_ON(!ordered); /* Logic error */
}
nr_sectors = APFS_BYTES_TO_BLKS(fs_info,
bvec.bv_len + fs_info->sectorsize
- 1);
for (i = 0; i < nr_sectors; i++) {
if (offset >= ordered->file_offset + ordered->num_bytes ||
offset < ordered->file_offset) {
unsigned long bytes_left;
sums->len = this_sum_bytes;
this_sum_bytes = 0;
apfs_add_ordered_sum(ordered, sums);
apfs_put_ordered_extent(ordered);
bytes_left = bio->bi_iter.bi_size - total_bytes;
nofs_flag = memalloc_nofs_save();
sums = kvzalloc(apfs_ordered_sum_size(fs_info,
bytes_left), GFP_KERNEL);
memalloc_nofs_restore(nofs_flag);
BUG_ON(!sums); /* -ENOMEM */
sums->len = bytes_left;
ordered = apfs_lookup_ordered_extent(inode,
offset);
ASSERT(ordered); /* Logic error */
sums->bytenr = (bio->bi_iter.bi_sector << 9)
+ total_bytes;
index = 0;
}
data = kmap_atomic(bvec.bv_page);
crypto_shash_digest(shash, data + bvec.bv_offset
+ (i * fs_info->sectorsize),
fs_info->sectorsize,
sums->sums + index);
kunmap_atomic(data);
index += fs_info->csum_size;
offset += fs_info->sectorsize;
this_sum_bytes += fs_info->sectorsize;
total_bytes += fs_info->sectorsize;
}
}
this_sum_bytes = 0;
apfs_add_ordered_sum(ordered, sums);
apfs_put_ordered_extent(ordered);
return 0;
}
/*
* helper function for csum removal, this expects the
* key to describe the csum pointed to by the path, and it expects
* the csum to overlap the range [bytenr, len]
*
* The csum should not be entirely contained in the range and the
* range should not be entirely contained in the csum.
*
* This calls apfs_truncate_item with the correct args based on the
* overlap, and fixes up the key as required.
*/
static noinline void truncate_one_csum(struct apfs_fs_info *fs_info,
struct apfs_path *path,
struct apfs_key *key,
u64 bytenr, u64 len)
{
struct extent_buffer *leaf;
const u32 csum_size = fs_info->csum_size;
u64 csum_end;
u64 end_byte = bytenr + len;
u32 blocksize_bits = fs_info->sectorsize_bits;
leaf = path->nodes[0];
csum_end = apfs_item_size_nr(leaf, path->slots[0]) / csum_size;
csum_end <<= blocksize_bits;
csum_end += key->offset;
if (key->offset < bytenr && csum_end <= end_byte) {
/*
* [ bytenr - len ]
* [ ]
* [csum ]
* A simple truncate off the end of the item
*/
u32 new_size = (bytenr - key->offset) >> blocksize_bits;
new_size *= csum_size;
apfs_truncate_item(path, new_size, 1);
} else if (key->offset >= bytenr && csum_end > end_byte &&
end_byte > key->offset) {
/*
* [ bytenr - len ]
* [ ]
* [csum ]
* we need to truncate from the beginning of the csum
*/
u32 new_size = (csum_end - end_byte) >> blocksize_bits;
new_size *= csum_size;
apfs_truncate_item(path, new_size, 0);
key->offset = end_byte;
apfs_set_item_key_safe(fs_info, path, key);
} else {
BUG();
}
}
/*
* deletes the csum items from the csum tree for a given
* range of bytes.
*/
int apfs_del_csums(struct apfs_trans_handle *trans,
struct apfs_root *root, u64 bytenr, u64 len)
{
struct apfs_fs_info *fs_info = trans->fs_info;
struct apfs_path *path;
struct apfs_key key = {};
u64 end_byte = bytenr + len;
u64 csum_end;
struct extent_buffer *leaf;
int ret = 0;
const u32 csum_size = fs_info->csum_size;
u32 blocksize_bits = fs_info->sectorsize_bits;
ASSERT(root == fs_info->csum_root ||
root->root_key.objectid == APFS_TREE_LOG_OBJECTID);
path = apfs_alloc_path();
if (!path)
return -ENOMEM;
while (1) {
key.objectid = APFS_EXTENT_CSUM_OBJECTID;
key.offset = end_byte - 1;
key.type = APFS_EXTENT_CSUM_KEY;
ret = apfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0) {
ret = 0;
if (path->slots[0] == 0)
break;
path->slots[0]--;
} else if (ret < 0) {
break;
}
leaf = path->nodes[0];
apfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.objectid != APFS_EXTENT_CSUM_OBJECTID ||
key.type != APFS_EXTENT_CSUM_KEY) {
break;
}
if (key.offset >= end_byte)
break;
csum_end = apfs_item_size_nr(leaf, path->slots[0]) / csum_size;
csum_end <<= blocksize_bits;
csum_end += key.offset;
/* this csum ends before we start, we're done */
if (csum_end <= bytenr)
break;
/* delete the entire item, it is inside our range */
if (key.offset >= bytenr && csum_end <= end_byte) {
int del_nr = 1;
/*
* Check how many csum items preceding this one in this
* leaf correspond to our range and then delete them all
* at once.
*/
if (key.offset > bytenr && path->slots[0] > 0) {
int slot = path->slots[0] - 1;
while (slot >= 0) {
struct apfs_key pk = {};
apfs_item_key_to_cpu(leaf, &pk, slot);
if (pk.offset < bytenr ||
pk.type != APFS_EXTENT_CSUM_KEY ||
pk.objectid !=
APFS_EXTENT_CSUM_OBJECTID)
break;
path->slots[0] = slot;
del_nr++;
key.offset = pk.offset;
slot--;
}
}
ret = apfs_del_items(trans, root, path,
path->slots[0], del_nr);
if (ret)
break;
if (key.offset == bytenr)
break;
} else if (key.offset < bytenr && csum_end > end_byte) {
unsigned long offset;
unsigned long shift_len;
unsigned long item_offset;
/*
* [ bytenr - len ]
* [csum ]
*
* Our bytes are in the middle of the csum,
* we need to split this item and insert a new one.
*
* But we can't drop the path because the
* csum could change, get removed, extended etc.
*
* The trick here is the max size of a csum item leaves
* enough room in the tree block for a single
* item header. So, we split the item in place,
* adding a new header pointing to the existing
* bytes. Then we loop around again and we have
* a nicely formed csum item that we can neatly
* truncate.
*/
offset = (bytenr - key.offset) >> blocksize_bits;
offset *= csum_size;
shift_len = (len >> blocksize_bits) * csum_size;
item_offset = apfs_item_ptr_offset(leaf,
path->slots[0]);
memzero_extent_buffer(leaf, item_offset + offset,
shift_len);
key.offset = bytenr;
/*
* apfs_split_item returns -EAGAIN when the
* item changed size or key
*/
ret = apfs_split_item(trans, root, path, &key, offset);
if (ret && ret != -EAGAIN) {
apfs_abort_transaction(trans, ret);
break;
}
ret = 0;
key.offset = end_byte - 1;
} else {
truncate_one_csum(fs_info, path, &key, bytenr, len);
if (key.offset < bytenr)
break;
}
apfs_release_path(path);
}
apfs_free_path(path);
return ret;
}
static int find_next_csum_offset(struct apfs_root *root,
struct apfs_path *path,
u64 *next_offset)
{
const u32 nritems = apfs_header_nritems(path->nodes[0]);
struct apfs_key found_key = {};
int slot = path->slots[0] + 1;
int ret;
if (nritems == 0 || slot >= nritems) {
ret = apfs_next_leaf(root, path);
if (ret < 0) {
return ret;
} else if (ret > 0) {
*next_offset = (u64)-1;
return 0;
}
slot = path->slots[0];
}
apfs_item_key_to_cpu(path->nodes[0], &found_key, slot);
if (found_key.objectid != APFS_EXTENT_CSUM_OBJECTID ||
found_key.type != APFS_EXTENT_CSUM_KEY)
*next_offset = (u64)-1;
else
*next_offset = found_key.offset;
return 0;
}
int apfs_csum_file_blocks(struct apfs_trans_handle *trans,
struct apfs_root *root,
struct apfs_ordered_sum *sums)
{
struct apfs_fs_info *fs_info = root->fs_info;
struct apfs_key file_key = {};
struct apfs_key found_key = {};
struct apfs_path *path;
struct apfs_csum_item *item;
struct apfs_csum_item *item_end;
struct extent_buffer *leaf = NULL;
u64 next_offset;
u64 total_bytes = 0;
u64 csum_offset;
u64 bytenr;
u32 ins_size;
int index = 0;
int found_next;
int ret;
const u32 csum_size = fs_info->csum_size;
path = apfs_alloc_path();
if (!path)
return -ENOMEM;
again:
next_offset = (u64)-1;
found_next = 0;
bytenr = sums->bytenr + total_bytes;
file_key.objectid = APFS_EXTENT_CSUM_OBJECTID;
file_key.offset = bytenr;
file_key.type = APFS_EXTENT_CSUM_KEY;
item = apfs_lookup_csum(trans, root, path, bytenr, 1);
if (!IS_ERR(item)) {
ret = 0;
leaf = path->nodes[0];
item_end = apfs_item_ptr(leaf, path->slots[0],
struct apfs_csum_item);
item_end = (struct apfs_csum_item *)((char *)item_end +