xref: /linux/include/scsi/scsi_common.h (revision b1968f46509e077d3241ac509e41fd14ec2395db)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Functions used by both the SCSI initiator code and the SCSI target code.
4  */
5 
6 #ifndef _SCSI_COMMON_H_
7 #define _SCSI_COMMON_H_
8 
9 #include <linux/types.h>
10 #include <uapi/linux/pr.h>
11 #include <scsi/scsi_proto.h>
12 
13 /* From the standard INQUIRY data description in SPC-6. */
14 #define INQUIRY_VENDOR_OFFSET	8
15 #define INQUIRY_VENDOR_LEN	8
16 #define INQUIRY_MODEL_OFFSET	16
17 #define INQUIRY_MODEL_LEN	16
18 #define INQUIRY_REVISION_OFFSET	32
19 #define INQUIRY_REVISION_LEN	4
20 
21 enum scsi_pr_type {
22 	SCSI_PR_WRITE_EXCLUSIVE			= 0x01,
23 	SCSI_PR_EXCLUSIVE_ACCESS		= 0x03,
24 	SCSI_PR_WRITE_EXCLUSIVE_REG_ONLY	= 0x05,
25 	SCSI_PR_EXCLUSIVE_ACCESS_REG_ONLY	= 0x06,
26 	SCSI_PR_WRITE_EXCLUSIVE_ALL_REGS	= 0x07,
27 	SCSI_PR_EXCLUSIVE_ACCESS_ALL_REGS	= 0x08,
28 };
29 
30 enum scsi_pr_type block_pr_type_to_scsi(enum pr_type type);
31 enum pr_type scsi_pr_type_to_block(enum scsi_pr_type type);
32 
33 static inline unsigned
34 scsi_varlen_cdb_length(const void *hdr)
35 {
36 	return ((struct scsi_varlen_cdb_hdr *)hdr)->additional_cdb_length + 8;
37 }
38 
39 extern const unsigned char scsi_command_size_tbl[8];
40 #define COMMAND_SIZE(opcode) scsi_command_size_tbl[((opcode) >> 5) & 7]
41 
42 static inline unsigned
43 scsi_command_size(const unsigned char *cmnd)
44 {
45 	return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
46 		scsi_varlen_cdb_length(cmnd) : COMMAND_SIZE(cmnd[0]);
47 }
48 
49 static inline unsigned char
50 scsi_command_control(const unsigned char *cmnd)
51 {
52 	return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
53 		cmnd[1] : cmnd[COMMAND_SIZE(cmnd[0]) - 1];
54 }
55 
56 /* Returns a human-readable name for the device */
57 extern const char *scsi_device_type(unsigned type);
58 
59 extern void int_to_scsilun(u64, struct scsi_lun *);
60 extern u64 scsilun_to_int(struct scsi_lun *);
61 
62 /*
63  * This is a slightly modified SCSI sense "descriptor" format header.
64  * The addition is to allow the 0x70 and 0x71 response codes. The idea
65  * is to place the salient data from either "fixed" or "descriptor" sense
66  * format into one structure to ease application processing.
67  *
68  * The original sense buffer should be kept around for those cases
69  * in which more information is required (e.g. the LBA of a MEDIUM ERROR).
70  */
71 struct scsi_sense_hdr {		/* See SPC-3 section 4.5 */
72 	u8 response_code;	/* permit: 0x0, 0x70, 0x71, 0x72, 0x73 */
73 	u8 sense_key;
74 	u8 asc;
75 	u8 ascq;
76 	u8 byte4;
77 	u8 byte5;
78 	u8 byte6;
79 	u8 additional_length;	/* always 0 for fixed sense format */
80 };
81 
82 static inline bool scsi_sense_valid(const struct scsi_sense_hdr *sshdr)
83 {
84 	if (!sshdr)
85 		return false;
86 
87 	return (sshdr->response_code & 0x70) == 0x70;
88 }
89 
90 extern bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
91 				 struct scsi_sense_hdr *sshdr);
92 
93 extern void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq);
94 int scsi_set_sense_information(u8 *buf, int buf_len, u64 info);
95 int scsi_set_sense_field_pointer(u8 *buf, int buf_len, u16 fp, u8 bp, bool cd);
96 extern const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
97 				       int desc_type);
98 
99 #endif /* _SCSI_COMMON_H_ */
100