1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef __TARGET_CORE_USER_H 3 #define __TARGET_CORE_USER_H 4 5 /* This header will be used by application too */ 6 7 #include <linux/types.h> 8 #include <linux/uio.h> 9 10 #define TCMU_VERSION "2.0" 11 12 /** 13 * DOC: Ring Design 14 * Ring Design 15 * ----------- 16 * 17 * The mmaped area is divided into three parts: 18 * 1) The mailbox (struct tcmu_mailbox, below); 19 * 2) The command ring; 20 * 3) Everything beyond the command ring (data). 21 * 22 * The mailbox tells userspace the offset of the command ring from the 23 * start of the shared memory region, and how big the command ring is. 24 * 25 * The kernel passes SCSI commands to userspace by putting a struct 26 * tcmu_cmd_entry in the ring, updating mailbox->cmd_head, and poking 27 * userspace via UIO's interrupt mechanism. 28 * 29 * tcmu_cmd_entry contains a header. If the header type is PAD, 30 * userspace should skip hdr->length bytes (mod cmdr_size) to find the 31 * next cmd_entry. 32 * 33 * Otherwise, the entry will contain offsets into the mmaped area that 34 * contain the cdb and data buffers -- the latter accessible via the 35 * iov array. iov addresses are also offsets into the shared area. 36 * 37 * When userspace is completed handling the command, set 38 * entry->rsp.scsi_status, fill in rsp.sense_buffer if appropriate, 39 * and also set mailbox->cmd_tail equal to the old cmd_tail plus 40 * hdr->length, mod cmdr_size. If cmd_tail doesn't equal cmd_head, it 41 * should process the next packet the same way, and so on. 42 */ 43 44 #define TCMU_MAILBOX_VERSION 2 45 #define ALIGN_SIZE 64 /* Should be enough for most CPUs */ 46 #define TCMU_MAILBOX_FLAG_CAP_OOOC (1 << 0) /* Out-of-order completions */ 47 #define TCMU_MAILBOX_FLAG_CAP_READ_LEN (1 << 1) /* Read data length */ 48 #define TCMU_MAILBOX_FLAG_CAP_TMR (1 << 2) /* TMR notifications */ 49 #define TCMU_MAILBOX_FLAG_CAP_KEEP_BUF (1<<3) /* Keep buf after cmd completion */ 50 51 struct tcmu_mailbox { 52 __u16 version; 53 __u16 flags; 54 __u32 cmdr_off; 55 __u32 cmdr_size; 56 57 __u32 cmd_head; 58 59 /* Updated by user. On its own cacheline */ 60 __u32 cmd_tail __attribute__((__aligned__(ALIGN_SIZE))); 61 62 } __packed; 63 64 enum tcmu_opcode { 65 TCMU_OP_PAD = 0, 66 TCMU_OP_CMD, 67 TCMU_OP_TMR, 68 }; 69 70 /* 71 * Only a few opcodes, and length is 8-byte aligned, so use low bits for opcode. 72 */ 73 struct tcmu_cmd_entry_hdr { 74 __u32 len_op; 75 __u16 cmd_id; 76 __u8 kflags; 77 #define TCMU_UFLAG_UNKNOWN_OP 0x1 78 #define TCMU_UFLAG_READ_LEN 0x2 79 #define TCMU_UFLAG_KEEP_BUF 0x4 80 __u8 uflags; 81 82 } __packed; 83 84 #define TCMU_OP_MASK 0x7 85 tcmu_hdr_get_op(__u32 len_op)86 static inline enum tcmu_opcode tcmu_hdr_get_op(__u32 len_op) 87 { 88 return len_op & TCMU_OP_MASK; 89 } 90 tcmu_hdr_set_op(__u32 * len_op,enum tcmu_opcode op)91 static inline void tcmu_hdr_set_op(__u32 *len_op, enum tcmu_opcode op) 92 { 93 *len_op &= ~TCMU_OP_MASK; 94 *len_op |= (op & TCMU_OP_MASK); 95 } 96 tcmu_hdr_get_len(__u32 len_op)97 static inline __u32 tcmu_hdr_get_len(__u32 len_op) 98 { 99 return len_op & ~TCMU_OP_MASK; 100 } 101 tcmu_hdr_set_len(__u32 * len_op,__u32 len)102 static inline void tcmu_hdr_set_len(__u32 *len_op, __u32 len) 103 { 104 *len_op &= TCMU_OP_MASK; 105 *len_op |= len; 106 } 107 108 /* Currently the same as SCSI_SENSE_BUFFERSIZE */ 109 #define TCMU_SENSE_BUFFERSIZE 96 110 111 struct tcmu_cmd_entry { 112 struct tcmu_cmd_entry_hdr hdr; 113 114 union { 115 struct { 116 __u32 iov_cnt; 117 __u32 iov_bidi_cnt; 118 __u32 iov_dif_cnt; 119 __u64 cdb_off; 120 __u64 __pad1; 121 __u64 __pad2; 122 __DECLARE_FLEX_ARRAY(struct iovec, iov); 123 } req; 124 struct { 125 __u8 scsi_status; 126 __u8 __pad1; 127 __u16 __pad2; 128 __u32 read_len; 129 char sense_buffer[TCMU_SENSE_BUFFERSIZE]; 130 } rsp; 131 }; 132 133 } __packed; 134 135 struct tcmu_tmr_entry { 136 struct tcmu_cmd_entry_hdr hdr; 137 138 #define TCMU_TMR_UNKNOWN 0 139 #define TCMU_TMR_ABORT_TASK 1 140 #define TCMU_TMR_ABORT_TASK_SET 2 141 #define TCMU_TMR_CLEAR_ACA 3 142 #define TCMU_TMR_CLEAR_TASK_SET 4 143 #define TCMU_TMR_LUN_RESET 5 144 #define TCMU_TMR_TARGET_WARM_RESET 6 145 #define TCMU_TMR_TARGET_COLD_RESET 7 146 /* Pseudo reset due to received PR OUT */ 147 #define TCMU_TMR_LUN_RESET_PRO 128 148 __u8 tmr_type; 149 150 __u8 __pad1; 151 __u16 __pad2; 152 __u32 cmd_cnt; 153 __u64 __pad3; 154 __u64 __pad4; 155 __u16 cmd_ids[]; 156 } __packed; 157 158 #define TCMU_OP_ALIGN_SIZE sizeof(__u64) 159 160 enum tcmu_genl_cmd { 161 TCMU_CMD_UNSPEC, 162 TCMU_CMD_ADDED_DEVICE, 163 TCMU_CMD_REMOVED_DEVICE, 164 TCMU_CMD_RECONFIG_DEVICE, 165 TCMU_CMD_ADDED_DEVICE_DONE, 166 TCMU_CMD_REMOVED_DEVICE_DONE, 167 TCMU_CMD_RECONFIG_DEVICE_DONE, 168 TCMU_CMD_SET_FEATURES, 169 __TCMU_CMD_MAX, 170 }; 171 #define TCMU_CMD_MAX (__TCMU_CMD_MAX - 1) 172 173 enum tcmu_genl_attr { 174 TCMU_ATTR_UNSPEC, 175 TCMU_ATTR_DEVICE, 176 TCMU_ATTR_MINOR, 177 TCMU_ATTR_PAD, 178 TCMU_ATTR_DEV_CFG, 179 TCMU_ATTR_DEV_SIZE, 180 TCMU_ATTR_WRITECACHE, 181 TCMU_ATTR_CMD_STATUS, 182 TCMU_ATTR_DEVICE_ID, 183 TCMU_ATTR_SUPP_KERN_CMD_REPLY, 184 __TCMU_ATTR_MAX, 185 }; 186 #define TCMU_ATTR_MAX (__TCMU_ATTR_MAX - 1) 187 188 #endif 189