1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_BLK_INTEGRITY_H
3#define _LINUX_BLK_INTEGRITY_H
4
5#include <linux/blk-mq.h>
6
7struct request;
8
9enum blk_integrity_flags {
10 BLK_INTEGRITY_VERIFY = 1 << 0,
11 BLK_INTEGRITY_GENERATE = 1 << 1,
12 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
13 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
14};
15
16struct blk_integrity_iter {
17 void *prot_buf;
18 void *data_buf;
19 sector_t seed;
20 unsigned int data_size;
21 unsigned short interval;
22 unsigned char tuple_size;
23 const char *disk_name;
24};
25
26typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
27typedef void (integrity_prepare_fn) (struct request *);
28typedef void (integrity_complete_fn) (struct request *, unsigned int);
29
30struct blk_integrity_profile {
31 integrity_processing_fn *generate_fn;
32 integrity_processing_fn *verify_fn;
33 integrity_prepare_fn *prepare_fn;
34 integrity_complete_fn *complete_fn;
35 const char *name;
36};
37
38#ifdef CONFIG_BLK_DEV_INTEGRITY
39void blk_integrity_register(struct gendisk *, struct blk_integrity *);
40void blk_integrity_unregister(struct gendisk *);
41int blk_integrity_compare(struct gendisk *, struct gendisk *);
42int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
43 struct scatterlist *);
44int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
45
46static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
47{
48 struct blk_integrity *bi = &disk->queue->integrity;
49
50 if (!bi->profile)
51 return NULL;
52
53 return bi;
54}
55
56static inline struct blk_integrity *
57bdev_get_integrity(struct block_device *bdev)
58{
59 return blk_get_integrity(disk: bdev->bd_disk);
60}
61
62static inline bool
63blk_integrity_queue_supports_integrity(struct request_queue *q)
64{
65 return q->integrity.profile;
66}
67
68static inline void blk_queue_max_integrity_segments(struct request_queue *q,
69 unsigned int segs)
70{
71 q->limits.max_integrity_segments = segs;
72}
73
74static inline unsigned short
75queue_max_integrity_segments(const struct request_queue *q)
76{
77 return q->limits.max_integrity_segments;
78}
79
80/**
81 * bio_integrity_intervals - Return number of integrity intervals for a bio
82 * @bi: blk_integrity profile for device
83 * @sectors: Size of the bio in 512-byte sectors
84 *
85 * Description: The block layer calculates everything in 512 byte
86 * sectors but integrity metadata is done in terms of the data integrity
87 * interval size of the storage device. Convert the block layer sectors
88 * to the appropriate number of integrity intervals.
89 */
90static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
91 unsigned int sectors)
92{
93 return sectors >> (bi->interval_exp - 9);
94}
95
96static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
97 unsigned int sectors)
98{
99 return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
100}
101
102static inline bool blk_integrity_rq(struct request *rq)
103{
104 return rq->cmd_flags & REQ_INTEGRITY;
105}
106
107/*
108 * Return the first bvec that contains integrity data. Only drivers that are
109 * limited to a single integrity segment should use this helper.
110 */
111static inline struct bio_vec *rq_integrity_vec(struct request *rq)
112{
113 if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1))
114 return NULL;
115 return rq->bio->bi_integrity->bip_vec;
116}
117#else /* CONFIG_BLK_DEV_INTEGRITY */
118static inline int blk_rq_count_integrity_sg(struct request_queue *q,
119 struct bio *b)
120{
121 return 0;
122}
123static inline int blk_rq_map_integrity_sg(struct request_queue *q,
124 struct bio *b,
125 struct scatterlist *s)
126{
127 return 0;
128}
129static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
130{
131 return NULL;
132}
133static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
134{
135 return NULL;
136}
137static inline bool
138blk_integrity_queue_supports_integrity(struct request_queue *q)
139{
140 return false;
141}
142static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
143{
144 return 0;
145}
146static inline void blk_integrity_register(struct gendisk *d,
147 struct blk_integrity *b)
148{
149}
150static inline void blk_integrity_unregister(struct gendisk *d)
151{
152}
153static inline void blk_queue_max_integrity_segments(struct request_queue *q,
154 unsigned int segs)
155{
156}
157static inline unsigned short
158queue_max_integrity_segments(const struct request_queue *q)
159{
160 return 0;
161}
162
163static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
164 unsigned int sectors)
165{
166 return 0;
167}
168
169static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
170 unsigned int sectors)
171{
172 return 0;
173}
174static inline int blk_integrity_rq(struct request *rq)
175{
176 return 0;
177}
178
179static inline struct bio_vec *rq_integrity_vec(struct request *rq)
180{
181 return NULL;
182}
183#endif /* CONFIG_BLK_DEV_INTEGRITY */
184#endif /* _LINUX_BLK_INTEGRITY_H */
185

source code of linux/include/linux/blk-integrity.h