1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_T10_PI_H
3 #define _LINUX_T10_PI_H
4
5 #include <linux/types.h>
6 #include <linux/blkdev.h>
7
8 /*
9 * A T10 PI-capable target device can be formatted with different
10 * protection schemes. Currently 0 through 3 are defined:
11 *
12 * Type 0 is regular (unprotected) I/O
13 *
14 * Type 1 defines the contents of the guard and reference tags
15 *
16 * Type 2 defines the contents of the guard and reference tags and
17 * uses 32-byte commands to seed the latter
18 *
19 * Type 3 defines the contents of the guard tag only
20 */
21 enum t10_dif_type {
22 T10_PI_TYPE0_PROTECTION = 0x0,
23 T10_PI_TYPE1_PROTECTION = 0x1,
24 T10_PI_TYPE2_PROTECTION = 0x2,
25 T10_PI_TYPE3_PROTECTION = 0x3,
26 };
27
28 /*
29 * T10 Protection Information tuple.
30 */
31 struct t10_pi_tuple {
32 __be16 guard_tag; /* Checksum */
33 __be16 app_tag; /* Opaque storage */
34 __be32 ref_tag; /* Target LBA or indirect LBA */
35 };
36
37 #define T10_PI_APP_ESCAPE cpu_to_be16(0xffff)
38 #define T10_PI_REF_ESCAPE cpu_to_be32(0xffffffff)
39
t10_pi_ref_tag(struct request * rq)40 static inline u32 t10_pi_ref_tag(struct request *rq)
41 {
42 #ifdef CONFIG_BLK_DEV_INTEGRITY
43 return blk_rq_pos(rq) >>
44 (rq->q->integrity.interval_exp - 9) & 0xffffffff;
45 #else
46 return -1U;
47 #endif
48 }
49
50 extern const struct blk_integrity_profile t10_pi_type1_crc;
51 extern const struct blk_integrity_profile t10_pi_type1_ip;
52 extern const struct blk_integrity_profile t10_pi_type3_crc;
53 extern const struct blk_integrity_profile t10_pi_type3_ip;
54
55 #ifdef CONFIG_BLK_DEV_INTEGRITY
56 extern void t10_pi_prepare(struct request *rq, u8 protection_type);
57 extern void t10_pi_complete(struct request *rq, u8 protection_type,
58 unsigned int intervals);
59 #else
t10_pi_complete(struct request * rq,u8 protection_type,unsigned int intervals)60 static inline void t10_pi_complete(struct request *rq, u8 protection_type,
61 unsigned int intervals)
62 {
63 }
t10_pi_prepare(struct request * rq,u8 protection_type)64 static inline void t10_pi_prepare(struct request *rq, u8 protection_type)
65 {
66 }
67 #endif
68
69 #endif
70
