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