xref: /openbmc/linux/include/linux/blk-integrity.h (revision ab3a560a)
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 
7 struct request;
8 
9 enum 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 
16 struct 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 
26 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
27 typedef void (integrity_prepare_fn) (struct request *);
28 typedef void (integrity_complete_fn) (struct request *, unsigned int);
29 
30 struct 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
39 void blk_integrity_register(struct gendisk *, struct blk_integrity *);
40 void blk_integrity_unregister(struct gendisk *);
41 int blk_integrity_compare(struct gendisk *, struct gendisk *);
42 int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
43 				   struct scatterlist *);
44 int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
45 
46 static 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 
56 static inline struct blk_integrity *
57 bdev_get_integrity(struct block_device *bdev)
58 {
59 	return blk_get_integrity(bdev->bd_disk);
60 }
61 
62 static inline bool
63 blk_integrity_queue_supports_integrity(struct request_queue *q)
64 {
65 	return q->integrity.profile;
66 }
67 
68 static 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 
74 static inline unsigned short
75 queue_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  */
90 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
91 						   unsigned int sectors)
92 {
93 	return sectors >> (bi->interval_exp - 9);
94 }
95 
96 static 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 
102 static 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  */
111 static 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 */
118 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
119 					    struct bio *b)
120 {
121 	return 0;
122 }
123 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
124 					  struct bio *b,
125 					  struct scatterlist *s)
126 {
127 	return 0;
128 }
129 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
130 {
131 	return NULL;
132 }
133 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
134 {
135 	return NULL;
136 }
137 static inline bool
138 blk_integrity_queue_supports_integrity(struct request_queue *q)
139 {
140 	return false;
141 }
142 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
143 {
144 	return 0;
145 }
146 static inline void blk_integrity_register(struct gendisk *d,
147 					 struct blk_integrity *b)
148 {
149 }
150 static inline void blk_integrity_unregister(struct gendisk *d)
151 {
152 }
153 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
154 						    unsigned int segs)
155 {
156 }
157 static inline unsigned short
158 queue_max_integrity_segments(const struct request_queue *q)
159 {
160 	return 0;
161 }
162 
163 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
164 						   unsigned int sectors)
165 {
166 	return 0;
167 }
168 
169 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
170 					       unsigned int sectors)
171 {
172 	return 0;
173 }
174 static inline int blk_integrity_rq(struct request *rq)
175 {
176 	return 0;
177 }
178 
179 static 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