diff options
Diffstat (limited to 'include/uapi/linux/target_core_user.h')
| -rw-r--r-- | include/uapi/linux/target_core_user.h | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/include/uapi/linux/target_core_user.h b/include/uapi/linux/target_core_user.h new file mode 100644 index 000000000..f925a77f1 --- /dev/null +++ b/include/uapi/linux/target_core_user.h @@ -0,0 +1,188 @@ +/* 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" + +/** + * DOC: Ring Design + * 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 */ +#define TCMU_MAILBOX_FLAG_CAP_READ_LEN (1 << 1) /* Read data length */ +#define TCMU_MAILBOX_FLAG_CAP_TMR (1 << 2) /* TMR notifications */ +#define TCMU_MAILBOX_FLAG_CAP_KEEP_BUF (1<<3) /* Keep buf after cmd completion */ + +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, + TCMU_OP_TMR, +}; + +/* + * 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 +#define TCMU_UFLAG_READ_LEN 0x2 +#define TCMU_UFLAG_KEEP_BUF 0x4 + __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; + __DECLARE_FLEX_ARRAY(struct iovec, iov); + } req; + struct { + __u8 scsi_status; + __u8 __pad1; + __u16 __pad2; + __u32 read_len; + char sense_buffer[TCMU_SENSE_BUFFERSIZE]; + } rsp; + }; + +} __packed; + +struct tcmu_tmr_entry { + struct tcmu_cmd_entry_hdr hdr; + +#define TCMU_TMR_UNKNOWN 0 +#define TCMU_TMR_ABORT_TASK 1 +#define TCMU_TMR_ABORT_TASK_SET 2 +#define TCMU_TMR_CLEAR_ACA 3 +#define TCMU_TMR_CLEAR_TASK_SET 4 +#define TCMU_TMR_LUN_RESET 5 +#define TCMU_TMR_TARGET_WARM_RESET 6 +#define TCMU_TMR_TARGET_COLD_RESET 7 +/* Pseudo reset due to received PR OUT */ +#define TCMU_TMR_LUN_RESET_PRO 128 + __u8 tmr_type; + + __u8 __pad1; + __u16 __pad2; + __u32 cmd_cnt; + __u64 __pad3; + __u64 __pad4; + __u16 cmd_ids[]; +} __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 |