1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 * Copyright (C) 2022 Christoph Hellwig.
5 */
6
7 #ifndef BTRFS_BIO_H
8 #define BTRFS_BIO_H
9
10 #include <linux/types.h>
11 #include <linux/bio.h>
12 #include <linux/workqueue.h>
13 #include "tree-checker.h"
14
15 struct btrfs_bio;
16 struct btrfs_fs_info;
17 struct btrfs_inode;
18
19 #define BTRFS_BIO_INLINE_CSUM_SIZE 64
20
21 /*
22 * Maximum number of sectors for a single bio to limit the size of the
23 * checksum array. This matches the number of bio_vecs per bio and thus the
24 * I/O size for buffered I/O.
25 */
26 #define BTRFS_MAX_BIO_SECTORS (256)
27
28 typedef void (*btrfs_bio_end_io_t)(struct btrfs_bio *bbio);
29
30 /*
31 * Highlevel btrfs I/O structure. It is allocated by btrfs_bio_alloc and
32 * passed to btrfs_submit_bbio() for mapping to the physical devices.
33 */
34 struct btrfs_bio {
35 /*
36 * Inode and offset into it that this I/O operates on.
37 * Only set for data I/O.
38 */
39 struct btrfs_inode *inode;
40 u64 file_offset;
41
42 union {
43 /*
44 * For data reads: checksumming and original I/O information.
45 * (for internal use in the btrfs_submit_bbio() machinery only)
46 */
47 struct {
48 u8 *csum;
49 u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
50 struct bvec_iter saved_iter;
51 };
52
53 /*
54 * For data writes:
55 * - ordered extent covering the bio
56 * - pointer to the checksums for this bio
57 * - original physical address from the allocator
58 * (for zone append only)
59 */
60 struct {
61 struct btrfs_ordered_extent *ordered;
62 struct btrfs_ordered_sum *sums;
63 u64 orig_physical;
64 };
65
66 /* For metadata reads: parentness verification. */
67 struct btrfs_tree_parent_check parent_check;
68 };
69
70 /* End I/O information supplied to btrfs_bio_alloc */
71 btrfs_bio_end_io_t end_io;
72 void *private;
73
74 /* For internal use in read end I/O handling */
75 unsigned int mirror_num;
76 atomic_t pending_ios;
77 struct work_struct end_io_work;
78
79 /* File system that this I/O operates on. */
80 struct btrfs_fs_info *fs_info;
81
82 /*
83 * This member must come last, bio_alloc_bioset will allocate enough
84 * bytes for entire btrfs_bio but relies on bio being last.
85 */
86 struct bio bio;
87 };
88
btrfs_bio(struct bio * bio)89 static inline struct btrfs_bio *btrfs_bio(struct bio *bio)
90 {
91 return container_of(bio, struct btrfs_bio, bio);
92 }
93
94 int __init btrfs_bioset_init(void);
95 void __cold btrfs_bioset_exit(void);
96
97 void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info,
98 btrfs_bio_end_io_t end_io, void *private);
99 struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
100 struct btrfs_fs_info *fs_info,
101 btrfs_bio_end_io_t end_io, void *private);
102 void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status);
103
104 /* Submit using blkcg_punt_bio_submit. */
105 #define REQ_BTRFS_CGROUP_PUNT REQ_FS_PRIVATE
106
107 void btrfs_submit_bbio(struct btrfs_bio *bbio, int mirror_num);
108 void btrfs_submit_repair_write(struct btrfs_bio *bbio, int mirror_num, bool dev_replace);
109 int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
110 u64 length, u64 logical, struct folio *folio,
111 unsigned int folio_offset, int mirror_num);
112
113 #endif
114