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(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