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 __u64 off; /* offset into file */ 23 __u64 addr; /* pointer to buffer or iovecs */ 24 __u32 len; /* buffer size or number of iovecs */ 25 union { 26 __kernel_rwf_t rw_flags; 27 __u32 fsync_flags; 28 __u16 poll_events; 29 __u32 sync_range_flags; 30 __u32 msg_flags; 31 __u32 timeout_flags; 32 }; 33 __u64 user_data; /* data to be passed back at completion time */ 34 union { 35 __u16 buf_index; /* index into fixed buffers, if used */ 36 __u64 __pad2[3]; 37 }; 38 }; 39 40 /* 41 * sqe->flags 42 */ 43 #define IOSQE_FIXED_FILE (1U << 0) /* use fixed fileset */ 44 #define IOSQE_IO_DRAIN (1U << 1) /* issue after inflight IO */ 45 #define IOSQE_IO_LINK (1U << 2) /* links next sqe */ 46 47 /* 48 * io_uring_setup() flags 49 */ 50 #define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */ 51 #define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */ 52 #define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */ 53 54 #define IORING_OP_NOP 0 55 #define IORING_OP_READV 1 56 #define IORING_OP_WRITEV 2 57 #define IORING_OP_FSYNC 3 58 #define IORING_OP_READ_FIXED 4 59 #define IORING_OP_WRITE_FIXED 5 60 #define IORING_OP_POLL_ADD 6 61 #define IORING_OP_POLL_REMOVE 7 62 #define IORING_OP_SYNC_FILE_RANGE 8 63 #define IORING_OP_SENDMSG 9 64 #define IORING_OP_RECVMSG 10 65 #define IORING_OP_TIMEOUT 11 66 67 /* 68 * sqe->fsync_flags 69 */ 70 #define IORING_FSYNC_DATASYNC (1U << 0) 71 72 /* 73 * IO completion data structure (Completion Queue Entry) 74 */ 75 struct io_uring_cqe { 76 __u64 user_data; /* sqe->data submission passed back */ 77 __s32 res; /* result code for this event */ 78 __u32 flags; 79 }; 80 81 /* 82 * Magic offsets for the application to mmap the data it needs 83 */ 84 #define IORING_OFF_SQ_RING 0ULL 85 #define IORING_OFF_CQ_RING 0x8000000ULL 86 #define IORING_OFF_SQES 0x10000000ULL 87 88 /* 89 * Filled with the offset for mmap(2) 90 */ 91 struct io_sqring_offsets { 92 __u32 head; 93 __u32 tail; 94 __u32 ring_mask; 95 __u32 ring_entries; 96 __u32 flags; 97 __u32 dropped; 98 __u32 array; 99 __u32 resv1; 100 __u64 resv2; 101 }; 102 103 /* 104 * sq_ring->flags 105 */ 106 #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */ 107 108 struct io_cqring_offsets { 109 __u32 head; 110 __u32 tail; 111 __u32 ring_mask; 112 __u32 ring_entries; 113 __u32 overflow; 114 __u32 cqes; 115 __u64 resv[2]; 116 }; 117 118 /* 119 * io_uring_enter(2) flags 120 */ 121 #define IORING_ENTER_GETEVENTS (1U << 0) 122 #define IORING_ENTER_SQ_WAKEUP (1U << 1) 123 124 /* 125 * Passed in for io_uring_setup(2). Copied back with updated info on success 126 */ 127 struct io_uring_params { 128 __u32 sq_entries; 129 __u32 cq_entries; 130 __u32 flags; 131 __u32 sq_thread_cpu; 132 __u32 sq_thread_idle; 133 __u32 features; 134 __u32 resv[4]; 135 struct io_sqring_offsets sq_off; 136 struct io_cqring_offsets cq_off; 137 }; 138 139 /* 140 * io_uring_params->features flags 141 */ 142 #define IORING_FEAT_SINGLE_MMAP (1U << 0) 143 144 /* 145 * io_uring_register(2) opcodes and arguments 146 */ 147 #define IORING_REGISTER_BUFFERS 0 148 #define IORING_UNREGISTER_BUFFERS 1 149 #define IORING_REGISTER_FILES 2 150 #define IORING_UNREGISTER_FILES 3 151 #define IORING_REGISTER_EVENTFD 4 152 #define IORING_UNREGISTER_EVENTFD 5 153 154 #endif 155
