Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 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 | |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 9 | #define TCMU_VERSION "2.0" |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 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 | |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 42 | #define TCMU_MAILBOX_VERSION 2 |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 43 | #define ALIGN_SIZE 64 /* Should be enough for most CPUs */ |
| 44 | |
| 45 | struct tcmu_mailbox { |
| 46 | __u16 version; |
| 47 | __u16 flags; |
| 48 | __u32 cmdr_off; |
| 49 | __u32 cmdr_size; |
| 50 | |
| 51 | __u32 cmd_head; |
| 52 | |
| 53 | /* Updated by user. On its own cacheline */ |
| 54 | __u32 cmd_tail __attribute__((__aligned__(ALIGN_SIZE))); |
| 55 | |
| 56 | } __packed; |
| 57 | |
| 58 | enum tcmu_opcode { |
| 59 | TCMU_OP_PAD = 0, |
| 60 | TCMU_OP_CMD, |
| 61 | }; |
| 62 | |
| 63 | /* |
| 64 | * Only a few opcodes, and length is 8-byte aligned, so use low bits for opcode. |
| 65 | */ |
| 66 | struct tcmu_cmd_entry_hdr { |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 67 | __u32 len_op; |
| 68 | __u16 cmd_id; |
| 69 | __u8 kflags; |
| 70 | #define TCMU_UFLAG_UNKNOWN_OP 0x1 |
| 71 | __u8 uflags; |
| 72 | |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 73 | } __packed; |
| 74 | |
| 75 | #define TCMU_OP_MASK 0x7 |
| 76 | |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 77 | static inline enum tcmu_opcode tcmu_hdr_get_op(__u32 len_op) |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 78 | { |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 79 | return len_op & TCMU_OP_MASK; |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 80 | } |
| 81 | |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 82 | static inline void tcmu_hdr_set_op(__u32 *len_op, enum tcmu_opcode op) |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 83 | { |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 84 | *len_op &= ~TCMU_OP_MASK; |
| 85 | *len_op |= (op & TCMU_OP_MASK); |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 86 | } |
| 87 | |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 88 | static inline __u32 tcmu_hdr_get_len(__u32 len_op) |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 89 | { |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 90 | return len_op & ~TCMU_OP_MASK; |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 91 | } |
| 92 | |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 93 | static inline void tcmu_hdr_set_len(__u32 *len_op, __u32 len) |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 94 | { |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 95 | *len_op &= TCMU_OP_MASK; |
| 96 | *len_op |= len; |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 97 | } |
| 98 | |
| 99 | /* Currently the same as SCSI_SENSE_BUFFERSIZE */ |
| 100 | #define TCMU_SENSE_BUFFERSIZE 96 |
| 101 | |
| 102 | struct tcmu_cmd_entry { |
| 103 | struct tcmu_cmd_entry_hdr hdr; |
| 104 | |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 105 | union { |
| 106 | struct { |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 107 | uint32_t iov_cnt; |
| 108 | uint32_t iov_bidi_cnt; |
| 109 | uint32_t iov_dif_cnt; |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 110 | uint64_t cdb_off; |
Christopher Ferris | 12e1f28 | 2016-02-04 12:35:07 -0800 | [diff] [blame^] | 111 | uint64_t __pad1; |
| 112 | uint64_t __pad2; |
Christopher Ferris | 7c0b639 | 2015-01-23 15:34:26 -0800 | [diff] [blame] | 113 | struct iovec iov[0]; |
| 114 | } req; |
| 115 | struct { |
| 116 | uint8_t scsi_status; |
| 117 | uint8_t __pad1; |
| 118 | uint16_t __pad2; |
| 119 | uint32_t __pad3; |
| 120 | char sense_buffer[TCMU_SENSE_BUFFERSIZE]; |
| 121 | } rsp; |
| 122 | }; |
| 123 | |
| 124 | } __packed; |
| 125 | |
| 126 | #define TCMU_OP_ALIGN_SIZE sizeof(uint64_t) |
| 127 | |
| 128 | enum tcmu_genl_cmd { |
| 129 | TCMU_CMD_UNSPEC, |
| 130 | TCMU_CMD_ADDED_DEVICE, |
| 131 | TCMU_CMD_REMOVED_DEVICE, |
| 132 | __TCMU_CMD_MAX, |
| 133 | }; |
| 134 | #define TCMU_CMD_MAX (__TCMU_CMD_MAX - 1) |
| 135 | |
| 136 | enum tcmu_genl_attr { |
| 137 | TCMU_ATTR_UNSPEC, |
| 138 | TCMU_ATTR_DEVICE, |
| 139 | TCMU_ATTR_MINOR, |
| 140 | __TCMU_ATTR_MAX, |
| 141 | }; |
| 142 | #define TCMU_ATTR_MAX (__TCMU_ATTR_MAX - 1) |
| 143 | |
| 144 | #endif |