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/blk-mq.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)40static inline u32 t10_pi_ref_tag(struct request *rq) 41 { 42 unsigned int shift = ilog2(queue_logical_block_size(rq->q)); 43 44 #ifdef CONFIG_BLK_DEV_INTEGRITY 45 if (rq->q->integrity.interval_exp) 46 shift = rq->q->integrity.interval_exp; 47 #endif 48 return blk_rq_pos(rq) >> (shift - SECTOR_SHIFT) & 0xffffffff; 49 } 50 51 extern const struct blk_integrity_profile t10_pi_type1_crc; 52 extern const struct blk_integrity_profile t10_pi_type1_ip; 53 extern const struct blk_integrity_profile t10_pi_type3_crc; 54 extern const struct blk_integrity_profile t10_pi_type3_ip; 55 56 struct crc64_pi_tuple { 57 __be64 guard_tag; 58 __be16 app_tag; 59 __u8 ref_tag[6]; 60 }; 61 62 /** 63 * lower_48_bits() - return bits 0-47 of a number 64 * @n: the number we're accessing 65 */ lower_48_bits(u64 n)66static inline u64 lower_48_bits(u64 n) 67 { 68 return n & ((1ull << 48) - 1); 69 } 70 ext_pi_ref_tag(struct request * rq)71static inline u64 ext_pi_ref_tag(struct request *rq) 72 { 73 unsigned int shift = ilog2(queue_logical_block_size(rq->q)); 74 75 #ifdef CONFIG_BLK_DEV_INTEGRITY 76 if (rq->q->integrity.interval_exp) 77 shift = rq->q->integrity.interval_exp; 78 #endif 79 return lower_48_bits(blk_rq_pos(rq) >> (shift - SECTOR_SHIFT)); 80 } 81 82 extern const struct blk_integrity_profile ext_pi_type1_crc64; 83 extern const struct blk_integrity_profile ext_pi_type3_crc64; 84 85 #endif 86