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 unsigned char pi_offset;
24 const char *disk_name;
25};
26
27typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
28typedef void (integrity_prepare_fn) (struct request *);
29typedef void (integrity_complete_fn) (struct request *, unsigned int);
30
31struct blk_integrity_profile {
32 integrity_processing_fn *generate_fn;
33 integrity_processing_fn *verify_fn;
34 integrity_prepare_fn *prepare_fn;
35 integrity_complete_fn *complete_fn;
36 const char *name;
37};
38
39#ifdef CONFIG_BLK_DEV_INTEGRITY
40void blk_integrity_register(struct gendisk *, struct blk_integrity *);
41void blk_integrity_unregister(struct gendisk *);
42int blk_integrity_compare(struct gendisk *, struct gendisk *);
43int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
44 struct scatterlist *);
45int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
46
47static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
48{
49 struct blk_integrity *bi = &disk->queue->integrity;
50
51 if (!bi->profile)
52 return NULL;
53
54 return bi;
55}
56
57static inline struct blk_integrity *
58bdev_get_integrity(struct block_device *bdev)
59{
60 return blk_get_integrity(disk: bdev->bd_disk);
61}
62
63static inline bool
64blk_integrity_queue_supports_integrity(struct request_queue *q)
65{
66 return q->integrity.profile;
67}
68
69static inline void blk_queue_max_integrity_segments(struct request_queue *q,
70 unsigned int segs)
71{
72 q->limits.max_integrity_segments = segs;
73}
74
75static inline unsigned short
76queue_max_integrity_segments(const struct request_queue *q)
77{
78 return q->limits.max_integrity_segments;
79}
80
81/**
82 * bio_integrity_intervals - Return number of integrity intervals for a bio
83 * @bi: blk_integrity profile for device
84 * @sectors: Size of the bio in 512-byte sectors
85 *
86 * Description: The block layer calculates everything in 512 byte
87 * sectors but integrity metadata is done in terms of the data integrity
88 * interval size of the storage device. Convert the block layer sectors
89 * to the appropriate number of integrity intervals.
90 */
91static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
92 unsigned int sectors)
93{
94 return sectors >> (bi->interval_exp - 9);
95}
96
97static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
98 unsigned int sectors)
99{
100 return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
101}
102
103static inline bool blk_integrity_rq(struct request *rq)
104{
105 return rq->cmd_flags & REQ_INTEGRITY;
106}
107
108/*
109 * Return the first bvec that contains integrity data. Only drivers that are
110 * limited to a single integrity segment should use this helper.
111 */
112static inline struct bio_vec *rq_integrity_vec(struct request *rq)
113{
114 if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1))
115 return NULL;
116 return rq->bio->bi_integrity->bip_vec;
117}
118#else /* CONFIG_BLK_DEV_INTEGRITY */
119static inline int blk_rq_count_integrity_sg(struct request_queue *q,
120 struct bio *b)
121{
122 return 0;
123}
124static inline int blk_rq_map_integrity_sg(struct request_queue *q,
125 struct bio *b,
126 struct scatterlist *s)
127{
128 return 0;
129}
130static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
131{
132 return NULL;
133}
134static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
135{
136 return NULL;
137}
138static inline bool
139blk_integrity_queue_supports_integrity(struct request_queue *q)
140{
141 return false;
142}
143static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
144{
145 return 0;
146}
147static inline void blk_integrity_register(struct gendisk *d,
148 struct blk_integrity *b)
149{
150}
151static inline void blk_integrity_unregister(struct gendisk *d)
152{
153}
154static inline void blk_queue_max_integrity_segments(struct request_queue *q,
155 unsigned int segs)
156{
157}
158static inline unsigned short
159queue_max_integrity_segments(const struct request_queue *q)
160{
161 return 0;
162}
163
164static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
165 unsigned int sectors)
166{
167 return 0;
168}
169
170static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
171 unsigned int sectors)
172{
173 return 0;
174}
175static inline int blk_integrity_rq(struct request *rq)
176{
177 return 0;
178}
179
180static inline struct bio_vec *rq_integrity_vec(struct request *rq)
181{
182 return NULL;
183}
184#endif /* CONFIG_BLK_DEV_INTEGRITY */
185#endif /* _LINUX_BLK_INTEGRITY_H */
186

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