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 <scsi/scsi_proto.h>
11 
12 static inline unsigned
scsi_varlen_cdb_length(const void * hdr)13 scsi_varlen_cdb_length(const void *hdr)
14 {
15 	return ((struct scsi_varlen_cdb_hdr *)hdr)->additional_cdb_length + 8;
16 }
17 
18 extern const unsigned char scsi_command_size_tbl[8];
19 #define COMMAND_SIZE(opcode) scsi_command_size_tbl[((opcode) >> 5) & 7]
20 
21 static inline unsigned
scsi_command_size(const unsigned char * cmnd)22 scsi_command_size(const unsigned char *cmnd)
23 {
24 	return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
25 		scsi_varlen_cdb_length(cmnd) : COMMAND_SIZE(cmnd[0]);
26 }
27 
28 static inline unsigned char
scsi_command_control(const unsigned char * cmnd)29 scsi_command_control(const unsigned char *cmnd)
30 {
31 	return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
32 		cmnd[1] : cmnd[COMMAND_SIZE(cmnd[0]) - 1];
33 }
34 
35 /* Returns a human-readable name for the device */
36 extern const char *scsi_device_type(unsigned type);
37 
38 extern void int_to_scsilun(u64, struct scsi_lun *);
39 extern u64 scsilun_to_int(struct scsi_lun *);
40 
41 /*
42  * This is a slightly modified SCSI sense "descriptor" format header.
43  * The addition is to allow the 0x70 and 0x71 response codes. The idea
44  * is to place the salient data from either "fixed" or "descriptor" sense
45  * format into one structure to ease application processing.
46  *
47  * The original sense buffer should be kept around for those cases
48  * in which more information is required (e.g. the LBA of a MEDIUM ERROR).
49  */
50 struct scsi_sense_hdr {		/* See SPC-3 section 4.5 */
51 	u8 response_code;	/* permit: 0x0, 0x70, 0x71, 0x72, 0x73 */
52 	u8 sense_key;
53 	u8 asc;
54 	u8 ascq;
55 	u8 byte4;
56 	u8 byte5;
57 	u8 byte6;
58 	u8 additional_length;	/* always 0 for fixed sense format */
59 };
60 
scsi_sense_valid(const struct scsi_sense_hdr * sshdr)61 static inline bool scsi_sense_valid(const struct scsi_sense_hdr *sshdr)
62 {
63 	if (!sshdr)
64 		return false;
65 
66 	return (sshdr->response_code & 0x70) == 0x70;
67 }
68 
69 extern bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
70 				 struct scsi_sense_hdr *sshdr);
71 
72 extern void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq);
73 int scsi_set_sense_information(u8 *buf, int buf_len, u64 info);
74 int scsi_set_sense_field_pointer(u8 *buf, int buf_len, u16 fp, u8 bp, bool cd);
75 extern const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
76 				       int desc_type);
77 
78 #endif /* _SCSI_COMMON_H_ */
79