1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef BSG_H
3#define BSG_H
4
5#include <linux/types.h>
6
7#define BSG_PROTOCOL_SCSI 0
8
9#define BSG_SUB_PROTOCOL_SCSI_CMD 0
10#define BSG_SUB_PROTOCOL_SCSI_TMF 1
11#define BSG_SUB_PROTOCOL_SCSI_TRANSPORT 2
12
13/*
14 * For flag constants below:
15 * sg.h sg_io_hdr also has bits defined for it's flags member. These
16 * two flag values (0x10 and 0x20) have the same meaning in sg.h . For
17 * bsg the BSG_FLAG_Q_AT_HEAD flag is ignored since it is the deafult.
18 */
19#define BSG_FLAG_Q_AT_TAIL 0x10 /* default is Q_AT_HEAD */
20#define BSG_FLAG_Q_AT_HEAD 0x20
21
22struct sg_io_v4 {
23 __s32 guard; /* [i] 'Q' to differentiate from v3 */
24 __u32 protocol; /* [i] 0 -> SCSI , .... */
25 __u32 subprotocol; /* [i] 0 -> SCSI command, 1 -> SCSI task
26 management function, .... */
27
28 __u32 request_len; /* [i] in bytes */
29 __u64 request; /* [i], [*i] {SCSI: cdb} */
30 __u64 request_tag; /* [i] {SCSI: task tag (only if flagged)} */
31 __u32 request_attr; /* [i] {SCSI: task attribute} */
32 __u32 request_priority; /* [i] {SCSI: task priority} */
33 __u32 request_extra; /* [i] {spare, for padding} */
34 __u32 max_response_len; /* [i] in bytes */
35 __u64 response; /* [i], [*o] {SCSI: (auto)sense data} */
36
37 /* "dout_": data out (to device); "din_": data in (from device) */
38 __u32 dout_iovec_count; /* [i] 0 -> "flat" dout transfer else
39 dout_xfer points to array of iovec */
40 __u32 dout_xfer_len; /* [i] bytes to be transferred to device */
41 __u32 din_iovec_count; /* [i] 0 -> "flat" din transfer */
42 __u32 din_xfer_len; /* [i] bytes to be transferred from device */
43 __u64 dout_xferp; /* [i], [*i] */
44 __u64 din_xferp; /* [i], [*o] */
45
46 __u32 timeout; /* [i] units: millisecond */
47 __u32 flags; /* [i] bit mask */
48 __u64 usr_ptr; /* [i->o] unused internally */
49 __u32 spare_in; /* [i] */
50
51 __u32 driver_status; /* [o] 0 -> ok */
52 __u32 transport_status; /* [o] 0 -> ok */
53 __u32 device_status; /* [o] {SCSI: command completion status} */
54 __u32 retry_delay; /* [o] {SCSI: status auxiliary information} */
55 __u32 info; /* [o] additional information */
56 __u32 duration; /* [o] time to complete, in milliseconds */
57 __u32 response_len; /* [o] bytes of response actually written */
58 __s32 din_resid; /* [o] din_xfer_len - actual_din_xfer_len */
59 __s32 dout_resid; /* [o] dout_xfer_len - actual_dout_xfer_len */
60 __u64 generated_tag; /* [o] {SCSI: transport generated task tag} */
61 __u32 spare_out; /* [o] */
62
63 __u32 padding;
64};
65
66struct bsg_uring_cmd {
67 __u64 request; /* [i], [*i] command descriptor address */
68 __u32 request_len; /* [i] command descriptor length in bytes */
69 __u32 protocol; /* [i] protocol type (BSG_PROTOCOL_*) */
70 __u32 subprotocol; /* [i] subprotocol type (BSG_SUB_PROTOCOL_*) */
71 __u32 max_response_len; /* [i] response buffer size in bytes */
72
73 __u64 response; /* [i], [*o] response data address */
74 __u64 dout_xferp; /* [i], [*i] */
75 __u32 dout_xfer_len; /* [i] bytes to be transferred to device */
76 __u32 dout_iovec_count; /* [i] 0 -> "flat" dout transfer else
77 * dout_xferp points to array of iovec
78 */
79 __u64 din_xferp; /* [i], [*o] */
80 __u32 din_xfer_len; /* [i] bytes to be transferred from device */
81 __u32 din_iovec_count; /* [i] 0 -> "flat" din transfer */
82
83 __u32 timeout_ms; /* [i] timeout in milliseconds */
84 __u8 reserved[12]; /* reserved for future extension */
85};
86
87
88
89/*
90 * SCSI BSG io_uring completion (res2, 64-bit)
91 *
92 * When using BSG_PROTOCOL_SCSI + BSG_SUB_PROTOCOL_SCSI_CMD with
93 * IORING_OP_URING_CMD, the completion queue entry (CQE) contains:
94 * - result: errno (0 on success)
95 * - res2: packed SCSI status
96 *
97 * res2 bit layout:
98 * [0..7] device_status (SCSI status byte, e.g. CHECK_CONDITION)
99 * [8..15] driver_status (e.g. DRIVER_SENSE when sense data is valid)
100 * [16..23] host_status (e.g. DID_OK, DID_TIME_OUT)
101 * [24..31] sense_len_wr (bytes of sense data written to response buffer)
102 * [32..63] resid_len (residual transfer length)
103 */
104static __inline__ __u8 bsg_scsi_res2_device_status(__u64 res2)
105{
106 return res2 & 0xff;
107}
108static __inline__ __u8 bsg_scsi_res2_driver_status(__u64 res2)
109{
110 return res2 >> 8;
111}
112static __inline__ __u8 bsg_scsi_res2_host_status(__u64 res2)
113{
114 return res2 >> 16;
115}
116static __inline__ __u8 bsg_scsi_res2_sense_len(__u64 res2)
117{
118 return res2 >> 24;
119}
120static __inline__ __u32 bsg_scsi_res2_resid_len(__u64 res2)
121{
122 return res2 >> 32;
123}
124static __inline__ __u64 bsg_scsi_res2_build(__u8 device_status, __u8 driver_status,
125 __u8 host_status, __u8 sense_len_wr,
126 __u32 resid_len)
127{
128 return ((__u64)(__u32)(resid_len) << 32) |
129 ((__u64)sense_len_wr << 24) |
130 ((__u64)host_status << 16) |
131 ((__u64)driver_status << 8) |
132 (__u64)device_status;
133}
134
135#endif /* BSG_H */