xref: /linux/include/scsi/scsi_common.h (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * Functions used by both the SCSI initiator code and the SCSI target code.
3  */
4 
5 #ifndef _SCSI_COMMON_H_
6 #define _SCSI_COMMON_H_
7 
8 #include <linux/types.h>
9 #include <scsi/scsi_proto.h>
10 
11 static inline unsigned
12 scsi_varlen_cdb_length(const void *hdr)
13 {
14 	return ((struct scsi_varlen_cdb_hdr *)hdr)->additional_cdb_length + 8;
15 }
16 
17 extern const unsigned char scsi_command_size_tbl[8];
18 #define COMMAND_SIZE(opcode) scsi_command_size_tbl[((opcode) >> 5) & 7]
19 
20 static inline unsigned
21 scsi_command_size(const unsigned char *cmnd)
22 {
23 	return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
24 		scsi_varlen_cdb_length(cmnd) : COMMAND_SIZE(cmnd[0]);
25 }
26 
27 /* Returns a human-readable name for the device */
28 extern const char *scsi_device_type(unsigned type);
29 
30 extern void int_to_scsilun(u64, struct scsi_lun *);
31 extern u64 scsilun_to_int(struct scsi_lun *);
32 
33 /*
34  * This is a slightly modified SCSI sense "descriptor" format header.
35  * The addition is to allow the 0x70 and 0x71 response codes. The idea
36  * is to place the salient data from either "fixed" or "descriptor" sense
37  * format into one structure to ease application processing.
38  *
39  * The original sense buffer should be kept around for those cases
40  * in which more information is required (e.g. the LBA of a MEDIUM ERROR).
41  */
42 struct scsi_sense_hdr {		/* See SPC-3 section 4.5 */
43 	u8 response_code;	/* permit: 0x0, 0x70, 0x71, 0x72, 0x73 */
44 	u8 sense_key;
45 	u8 asc;
46 	u8 ascq;
47 	u8 byte4;
48 	u8 byte5;
49 	u8 byte6;
50 	u8 additional_length;	/* always 0 for fixed sense format */
51 };
52 
53 static inline bool scsi_sense_valid(const struct scsi_sense_hdr *sshdr)
54 {
55 	if (!sshdr)
56 		return false;
57 
58 	return (sshdr->response_code & 0x70) == 0x70;
59 }
60 
61 extern bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
62 				 struct scsi_sense_hdr *sshdr);
63 
64 extern void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq);
65 int scsi_set_sense_information(u8 *buf, int buf_len, u64 info);
66 int scsi_set_sense_field_pointer(u8 *buf, int buf_len, u16 fp, u8 bp, bool cd);
67 extern const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
68 				       int desc_type);
69 
70 #endif /* _SCSI_COMMON_H_ */
71