1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 /* 3 * Header file for the io_uring interface. 4 * 5 * Copyright (C) 2019 Jens Axboe 6 * Copyright (C) 2019 Christoph Hellwig 7 */ 8 #ifndef LINUX_IO_URING_H 9 #define LINUX_IO_URING_H 10 11 #include <linux/fs.h> 12 #include <linux/types.h> 13 14 /* 15 * IO submission data structure (Submission Queue Entry) 16 */ 17 struct io_uring_sqe { 18 __u8 opcode; /* type of operation for this sqe */ 19 __u8 flags; /* IOSQE_ flags */ 20 __u16 ioprio; /* ioprio for the request */ 21 __s32 fd; /* file descriptor to do IO on */ 22 union { 23 __u64 off; /* offset into file */ 24 __u64 addr2; 25 }; 26 __u64 addr; /* pointer to buffer or iovecs */ 27 __u32 len; /* buffer size or number of iovecs */ 28 union { 29 __kernel_rwf_t rw_flags; 30 __u32 fsync_flags; 31 __u16 poll_events; 32 __u32 sync_range_flags; 33 __u32 msg_flags; 34 __u32 timeout_flags; 35 __u32 accept_flags; 36 __u32 cancel_flags; 37 }; 38 __u64 user_data; /* data to be passed back at completion time */ 39 union { 40 __u16 buf_index; /* index into fixed buffers, if used */ 41 __u64 __pad2[3]; 42 }; 43 }; 44 45 /* 46 * sqe->flags 47 */ 48 #define IOSQE_FIXED_FILE (1U << 0) /* use fixed fileset */ 49 #define IOSQE_IO_DRAIN (1U << 1) /* issue after inflight IO */ 50 #define IOSQE_IO_LINK (1U << 2) /* links next sqe */ 51 52 /* 53 * io_uring_setup() flags 54 */ 55 #define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */ 56 #define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */ 57 #define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */ 58 #define IORING_SETUP_CQSIZE (1U << 3) /* app defines CQ size */ 59 60 #define IORING_OP_NOP 0 61 #define IORING_OP_READV 1 62 #define IORING_OP_WRITEV 2 63 #define IORING_OP_FSYNC 3 64 #define IORING_OP_READ_FIXED 4 65 #define IORING_OP_WRITE_FIXED 5 66 #define IORING_OP_POLL_ADD 6 67 #define IORING_OP_POLL_REMOVE 7 68 #define IORING_OP_SYNC_FILE_RANGE 8 69 #define IORING_OP_SENDMSG 9 70 #define IORING_OP_RECVMSG 10 71 #define IORING_OP_TIMEOUT 11 72 #define IORING_OP_TIMEOUT_REMOVE 12 73 #define IORING_OP_ACCEPT 13 74 #define IORING_OP_ASYNC_CANCEL 14 75 #define IORING_OP_LINK_TIMEOUT 15 76 77 /* 78 * sqe->fsync_flags 79 */ 80 #define IORING_FSYNC_DATASYNC (1U << 0) 81 82 /* 83 * sqe->timeout_flags 84 */ 85 #define IORING_TIMEOUT_ABS (1U << 0) 86 87 /* 88 * IO completion data structure (Completion Queue Entry) 89 */ 90 struct io_uring_cqe { 91 __u64 user_data; /* sqe->data submission passed back */ 92 __s32 res; /* result code for this event */ 93 __u32 flags; 94 }; 95 96 /* 97 * Magic offsets for the application to mmap the data it needs 98 */ 99 #define IORING_OFF_SQ_RING 0ULL 100 #define IORING_OFF_CQ_RING 0x8000000ULL 101 #define IORING_OFF_SQES 0x10000000ULL 102 103 /* 104 * Filled with the offset for mmap(2) 105 */ 106 struct io_sqring_offsets { 107 __u32 head; 108 __u32 tail; 109 __u32 ring_mask; 110 __u32 ring_entries; 111 __u32 flags; 112 __u32 dropped; 113 __u32 array; 114 __u32 resv1; 115 __u64 resv2; 116 }; 117 118 /* 119 * sq_ring->flags 120 */ 121 #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */ 122 123 struct io_cqring_offsets { 124 __u32 head; 125 __u32 tail; 126 __u32 ring_mask; 127 __u32 ring_entries; 128 __u32 overflow; 129 __u32 cqes; 130 __u64 resv[2]; 131 }; 132 133 /* 134 * io_uring_enter(2) flags 135 */ 136 #define IORING_ENTER_GETEVENTS (1U << 0) 137 #define IORING_ENTER_SQ_WAKEUP (1U << 1) 138 139 /* 140 * Passed in for io_uring_setup(2). Copied back with updated info on success 141 */ 142 struct io_uring_params { 143 __u32 sq_entries; 144 __u32 cq_entries; 145 __u32 flags; 146 __u32 sq_thread_cpu; 147 __u32 sq_thread_idle; 148 __u32 features; 149 __u32 resv[4]; 150 struct io_sqring_offsets sq_off; 151 struct io_cqring_offsets cq_off; 152 }; 153 154 /* 155 * io_uring_params->features flags 156 */ 157 #define IORING_FEAT_SINGLE_MMAP (1U << 0) 158 #define IORING_FEAT_NODROP (1U << 1) 159 160 /* 161 * io_uring_register(2) opcodes and arguments 162 */ 163 #define IORING_REGISTER_BUFFERS 0 164 #define IORING_UNREGISTER_BUFFERS 1 165 #define IORING_REGISTER_FILES 2 166 #define IORING_UNREGISTER_FILES 3 167 #define IORING_REGISTER_EVENTFD 4 168 #define IORING_UNREGISTER_EVENTFD 5 169 #define IORING_REGISTER_FILES_UPDATE 6 170 171 struct io_uring_files_update { 172 __u32 offset; 173 __s32 *fds; 174 }; 175 176 #endif 177