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7c9e7a6f AG |
1 | #ifndef __TARGET_CORE_USER_H |
2 | #define __TARGET_CORE_USER_H | |
3 | ||
4 | /* This header will be used by application too */ | |
5 | ||
6 | #include <linux/types.h> | |
7 | #include <linux/uio.h> | |
8 | ||
0ad46af8 | 9 | #define TCMU_VERSION "2.0" |
7c9e7a6f AG |
10 | |
11 | /* | |
12 | * Ring Design | |
13 | * ----------- | |
14 | * | |
15 | * The mmaped area is divided into three parts: | |
16 | * 1) The mailbox (struct tcmu_mailbox, below) | |
17 | * 2) The command ring | |
18 | * 3) Everything beyond the command ring (data) | |
19 | * | |
20 | * The mailbox tells userspace the offset of the command ring from the | |
21 | * start of the shared memory region, and how big the command ring is. | |
22 | * | |
23 | * The kernel passes SCSI commands to userspace by putting a struct | |
24 | * tcmu_cmd_entry in the ring, updating mailbox->cmd_head, and poking | |
25 | * userspace via uio's interrupt mechanism. | |
26 | * | |
27 | * tcmu_cmd_entry contains a header. If the header type is PAD, | |
28 | * userspace should skip hdr->length bytes (mod cmdr_size) to find the | |
29 | * next cmd_entry. | |
30 | * | |
31 | * Otherwise, the entry will contain offsets into the mmaped area that | |
32 | * contain the cdb and data buffers -- the latter accessible via the | |
33 | * iov array. iov addresses are also offsets into the shared area. | |
34 | * | |
35 | * When userspace is completed handling the command, set | |
36 | * entry->rsp.scsi_status, fill in rsp.sense_buffer if appropriate, | |
37 | * and also set mailbox->cmd_tail equal to the old cmd_tail plus | |
38 | * hdr->length, mod cmdr_size. If cmd_tail doesn't equal cmd_head, it | |
39 | * should process the next packet the same way, and so on. | |
40 | */ | |
41 | ||
0ad46af8 | 42 | #define TCMU_MAILBOX_VERSION 2 |
7c9e7a6f | 43 | #define ALIGN_SIZE 64 /* Should be enough for most CPUs */ |
32c76de3 | 44 | #define TCMU_MAILBOX_FLAG_CAP_OOOC (1 << 0) /* Out-of-order completions */ |
7c9e7a6f AG |
45 | |
46 | struct tcmu_mailbox { | |
47 | __u16 version; | |
48 | __u16 flags; | |
49 | __u32 cmdr_off; | |
50 | __u32 cmdr_size; | |
51 | ||
52 | __u32 cmd_head; | |
53 | ||
54 | /* Updated by user. On its own cacheline */ | |
55 | __u32 cmd_tail __attribute__((__aligned__(ALIGN_SIZE))); | |
56 | ||
57 | } __packed; | |
58 | ||
59 | enum tcmu_opcode { | |
60 | TCMU_OP_PAD = 0, | |
61 | TCMU_OP_CMD, | |
62 | }; | |
63 | ||
64 | /* | |
65 | * Only a few opcodes, and length is 8-byte aligned, so use low bits for opcode. | |
66 | */ | |
67 | struct tcmu_cmd_entry_hdr { | |
0ad46af8 AG |
68 | __u32 len_op; |
69 | __u16 cmd_id; | |
70 | __u8 kflags; | |
71 | #define TCMU_UFLAG_UNKNOWN_OP 0x1 | |
72 | __u8 uflags; | |
73 | ||
7c9e7a6f AG |
74 | } __packed; |
75 | ||
76 | #define TCMU_OP_MASK 0x7 | |
77 | ||
0ad46af8 | 78 | static inline enum tcmu_opcode tcmu_hdr_get_op(__u32 len_op) |
7c9e7a6f | 79 | { |
0ad46af8 | 80 | return len_op & TCMU_OP_MASK; |
7c9e7a6f AG |
81 | } |
82 | ||
0ad46af8 | 83 | static inline void tcmu_hdr_set_op(__u32 *len_op, enum tcmu_opcode op) |
7c9e7a6f | 84 | { |
0ad46af8 AG |
85 | *len_op &= ~TCMU_OP_MASK; |
86 | *len_op |= (op & TCMU_OP_MASK); | |
7c9e7a6f AG |
87 | } |
88 | ||
0ad46af8 | 89 | static inline __u32 tcmu_hdr_get_len(__u32 len_op) |
7c9e7a6f | 90 | { |
0ad46af8 | 91 | return len_op & ~TCMU_OP_MASK; |
7c9e7a6f AG |
92 | } |
93 | ||
0ad46af8 | 94 | static inline void tcmu_hdr_set_len(__u32 *len_op, __u32 len) |
7c9e7a6f | 95 | { |
0ad46af8 AG |
96 | *len_op &= TCMU_OP_MASK; |
97 | *len_op |= len; | |
7c9e7a6f AG |
98 | } |
99 | ||
100 | /* Currently the same as SCSI_SENSE_BUFFERSIZE */ | |
101 | #define TCMU_SENSE_BUFFERSIZE 96 | |
102 | ||
103 | struct tcmu_cmd_entry { | |
104 | struct tcmu_cmd_entry_hdr hdr; | |
105 | ||
7c9e7a6f AG |
106 | union { |
107 | struct { | |
0ad46af8 AG |
108 | uint32_t iov_cnt; |
109 | uint32_t iov_bidi_cnt; | |
110 | uint32_t iov_dif_cnt; | |
7c9e7a6f | 111 | uint64_t cdb_off; |
0ad46af8 AG |
112 | uint64_t __pad1; |
113 | uint64_t __pad2; | |
7c9e7a6f AG |
114 | struct iovec iov[0]; |
115 | } req; | |
116 | struct { | |
117 | uint8_t scsi_status; | |
118 | uint8_t __pad1; | |
119 | uint16_t __pad2; | |
120 | uint32_t __pad3; | |
121 | char sense_buffer[TCMU_SENSE_BUFFERSIZE]; | |
122 | } rsp; | |
123 | }; | |
124 | ||
125 | } __packed; | |
126 | ||
127 | #define TCMU_OP_ALIGN_SIZE sizeof(uint64_t) | |
128 | ||
129 | enum tcmu_genl_cmd { | |
130 | TCMU_CMD_UNSPEC, | |
131 | TCMU_CMD_ADDED_DEVICE, | |
132 | TCMU_CMD_REMOVED_DEVICE, | |
133 | __TCMU_CMD_MAX, | |
134 | }; | |
135 | #define TCMU_CMD_MAX (__TCMU_CMD_MAX - 1) | |
136 | ||
137 | enum tcmu_genl_attr { | |
138 | TCMU_ATTR_UNSPEC, | |
139 | TCMU_ATTR_DEVICE, | |
140 | TCMU_ATTR_MINOR, | |
141 | __TCMU_ATTR_MAX, | |
142 | }; | |
143 | #define TCMU_ATTR_MAX (__TCMU_ATTR_MAX - 1) | |
144 | ||
145 | #endif |