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