| /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ |
| #ifndef __TARGET_CORE_USER_H |
| #define __TARGET_CORE_USER_H |
| |
| /* This header will be used by application too */ |
| |
| #include <linux/types.h> |
| #include <linux/uio.h> |
| |
| #define TCMU_VERSION "2.0" |
| |
| /* |
| * Ring Design |
| * ----------- |
| * |
| * The mmaped area is divided into three parts: |
| * 1) The mailbox (struct tcmu_mailbox, below) |
| * 2) The command ring |
| * 3) Everything beyond the command ring (data) |
| * |
| * The mailbox tells userspace the offset of the command ring from the |
| * start of the shared memory region, and how big the command ring is. |
| * |
| * The kernel passes SCSI commands to userspace by putting a struct |
| * tcmu_cmd_entry in the ring, updating mailbox->cmd_head, and poking |
| * userspace via uio's interrupt mechanism. |
| * |
| * tcmu_cmd_entry contains a header. If the header type is PAD, |
| * userspace should skip hdr->length bytes (mod cmdr_size) to find the |
| * next cmd_entry. |
| * |
| * Otherwise, the entry will contain offsets into the mmaped area that |
| * contain the cdb and data buffers -- the latter accessible via the |
| * iov array. iov addresses are also offsets into the shared area. |
| * |
| * When userspace is completed handling the command, set |
| * entry->rsp.scsi_status, fill in rsp.sense_buffer if appropriate, |
| * and also set mailbox->cmd_tail equal to the old cmd_tail plus |
| * hdr->length, mod cmdr_size. If cmd_tail doesn't equal cmd_head, it |
| * should process the next packet the same way, and so on. |
| */ |
| |
| #define TCMU_MAILBOX_VERSION 2 |
| #define ALIGN_SIZE 64 /* Should be enough for most CPUs */ |
| #define TCMU_MAILBOX_FLAG_CAP_OOOC (1 << 0) /* Out-of-order completions */ |
| |
| struct tcmu_mailbox { |
| __u16 version; |
| __u16 flags; |
| __u32 cmdr_off; |
| __u32 cmdr_size; |
| |
| __u32 cmd_head; |
| |
| /* Updated by user. On its own cacheline */ |
| __u32 cmd_tail __attribute__((__aligned__(ALIGN_SIZE))); |
| |
| } __packed; |
| |
| enum tcmu_opcode { |
| TCMU_OP_PAD = 0, |
| TCMU_OP_CMD, |
| }; |
| |
| /* |
| * Only a few opcodes, and length is 8-byte aligned, so use low bits for opcode. |
| */ |
| struct tcmu_cmd_entry_hdr { |
| __u32 len_op; |
| __u16 cmd_id; |
| __u8 kflags; |
| #define TCMU_UFLAG_UNKNOWN_OP 0x1 |
| __u8 uflags; |
| |
| } __packed; |
| |
| #define TCMU_OP_MASK 0x7 |
| |
| static inline enum tcmu_opcode tcmu_hdr_get_op(__u32 len_op) |
| { |
| return len_op & TCMU_OP_MASK; |
| } |
| |
| static inline void tcmu_hdr_set_op(__u32 *len_op, enum tcmu_opcode op) |
| { |
| *len_op &= ~TCMU_OP_MASK; |
| *len_op |= (op & TCMU_OP_MASK); |
| } |
| |
| static inline __u32 tcmu_hdr_get_len(__u32 len_op) |
| { |
| return len_op & ~TCMU_OP_MASK; |
| } |
| |
| static inline void tcmu_hdr_set_len(__u32 *len_op, __u32 len) |
| { |
| *len_op &= TCMU_OP_MASK; |
| *len_op |= len; |
| } |
| |
| /* Currently the same as SCSI_SENSE_BUFFERSIZE */ |
| #define TCMU_SENSE_BUFFERSIZE 96 |
| |
| struct tcmu_cmd_entry { |
| struct tcmu_cmd_entry_hdr hdr; |
| |
| union { |
| struct { |
| __u32 iov_cnt; |
| __u32 iov_bidi_cnt; |
| __u32 iov_dif_cnt; |
| __u64 cdb_off; |
| __u64 __pad1; |
| __u64 __pad2; |
| struct iovec iov[0]; |
| } req; |
| struct { |
| __u8 scsi_status; |
| __u8 __pad1; |
| __u16 __pad2; |
| __u32 __pad3; |
| char sense_buffer[TCMU_SENSE_BUFFERSIZE]; |
| } rsp; |
| }; |
| |
| } __packed; |
| |
| #define TCMU_OP_ALIGN_SIZE sizeof(__u64) |
| |
| enum tcmu_genl_cmd { |
| TCMU_CMD_UNSPEC, |
| TCMU_CMD_ADDED_DEVICE, |
| TCMU_CMD_REMOVED_DEVICE, |
| TCMU_CMD_RECONFIG_DEVICE, |
| TCMU_CMD_ADDED_DEVICE_DONE, |
| TCMU_CMD_REMOVED_DEVICE_DONE, |
| TCMU_CMD_RECONFIG_DEVICE_DONE, |
| TCMU_CMD_SET_FEATURES, |
| __TCMU_CMD_MAX, |
| }; |
| #define TCMU_CMD_MAX (__TCMU_CMD_MAX - 1) |
| |
| enum tcmu_genl_attr { |
| TCMU_ATTR_UNSPEC, |
| TCMU_ATTR_DEVICE, |
| TCMU_ATTR_MINOR, |
| TCMU_ATTR_PAD, |
| TCMU_ATTR_DEV_CFG, |
| TCMU_ATTR_DEV_SIZE, |
| TCMU_ATTR_WRITECACHE, |
| TCMU_ATTR_CMD_STATUS, |
| TCMU_ATTR_DEVICE_ID, |
| TCMU_ATTR_SUPP_KERN_CMD_REPLY, |
| __TCMU_ATTR_MAX, |
| }; |
| #define TCMU_ATTR_MAX (__TCMU_ATTR_MAX - 1) |
| |
| #endif |