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 #define IORING_OP_CONNECT 16 77 78 /* 79 * sqe->fsync_flags 80 */ 81 #define IORING_FSYNC_DATASYNC (1U << 0) 82 83 /* 84 * sqe->timeout_flags 85 */ 86 #define IORING_TIMEOUT_ABS (1U << 0) 87 88 /* 89 * IO completion data structure (Completion Queue Entry) 90 */ 91 struct io_uring_cqe { 92 __u64 user_data; /* sqe->data submission passed back */ 93 __s32 res; /* result code for this event */ 94 __u32 flags; 95 }; 96 97 /* 98 * Magic offsets for the application to mmap the data it needs 99 */ 100 #define IORING_OFF_SQ_RING 0ULL 101 #define IORING_OFF_CQ_RING 0x8000000ULL 102 #define IORING_OFF_SQES 0x10000000ULL 103 104 /* 105 * Filled with the offset for mmap(2) 106 */ 107 struct io_sqring_offsets { 108 __u32 head; 109 __u32 tail; 110 __u32 ring_mask; 111 __u32 ring_entries; 112 __u32 flags; 113 __u32 dropped; 114 __u32 array; 115 __u32 resv1; 116 __u64 resv2; 117 }; 118 119 /* 120 * sq_ring->flags 121 */ 122 #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */ 123 124 struct io_cqring_offsets { 125 __u32 head; 126 __u32 tail; 127 __u32 ring_mask; 128 __u32 ring_entries; 129 __u32 overflow; 130 __u32 cqes; 131 __u64 resv[2]; 132 }; 133 134 /* 135 * io_uring_enter(2) flags 136 */ 137 #define IORING_ENTER_GETEVENTS (1U << 0) 138 #define IORING_ENTER_SQ_WAKEUP (1U << 1) 139 140 /* 141 * Passed in for io_uring_setup(2). Copied back with updated info on success 142 */ 143 struct io_uring_params { 144 __u32 sq_entries; 145 __u32 cq_entries; 146 __u32 flags; 147 __u32 sq_thread_cpu; 148 __u32 sq_thread_idle; 149 __u32 features; 150 __u32 resv[4]; 151 struct io_sqring_offsets sq_off; 152 struct io_cqring_offsets cq_off; 153 }; 154 155 /* 156 * io_uring_params->features flags 157 */ 158 #define IORING_FEAT_SINGLE_MMAP (1U << 0) 159 #define IORING_FEAT_NODROP (1U << 1) 160 #define IORING_FEAT_SUBMIT_STABLE (1U << 2) 161 162 /* 163 * io_uring_register(2) opcodes and arguments 164 */ 165 #define IORING_REGISTER_BUFFERS 0 166 #define IORING_UNREGISTER_BUFFERS 1 167 #define IORING_REGISTER_FILES 2 168 #define IORING_UNREGISTER_FILES 3 169 #define IORING_REGISTER_EVENTFD 4 170 #define IORING_UNREGISTER_EVENTFD 5 171 #define IORING_REGISTER_FILES_UPDATE 6 172 173 struct io_uring_files_update { 174 __u32 offset; 175 __s32 *fds; 176 }; 177 178 #endif 179