xref: /linux-6.15/include/uapi/linux/io_uring.h (revision fc5dfebc)
1 /* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT */
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 #include <linux/time_types.h>
14 
15 #ifdef __cplusplus
16 extern "C" {
17 #endif
18 
19 /*
20  * IO submission data structure (Submission Queue Entry)
21  */
22 struct io_uring_sqe {
23 	__u8	opcode;		/* type of operation for this sqe */
24 	__u8	flags;		/* IOSQE_ flags */
25 	__u16	ioprio;		/* ioprio for the request */
26 	__s32	fd;		/* file descriptor to do IO on */
27 	union {
28 		__u64	off;	/* offset into file */
29 		__u64	addr2;
30 		struct {
31 			__u32	cmd_op;
32 			__u32	__pad1;
33 		};
34 	};
35 	union {
36 		__u64	addr;	/* pointer to buffer or iovecs */
37 		__u64	splice_off_in;
38 	};
39 	__u32	len;		/* buffer size or number of iovecs */
40 	union {
41 		__kernel_rwf_t	rw_flags;
42 		__u32		fsync_flags;
43 		__u16		poll_events;	/* compatibility */
44 		__u32		poll32_events;	/* word-reversed for BE */
45 		__u32		sync_range_flags;
46 		__u32		msg_flags;
47 		__u32		timeout_flags;
48 		__u32		accept_flags;
49 		__u32		cancel_flags;
50 		__u32		open_flags;
51 		__u32		statx_flags;
52 		__u32		fadvise_advice;
53 		__u32		splice_flags;
54 		__u32		rename_flags;
55 		__u32		unlink_flags;
56 		__u32		hardlink_flags;
57 		__u32		xattr_flags;
58 		__u32		msg_ring_flags;
59 	};
60 	__u64	user_data;	/* data to be passed back at completion time */
61 	/* pack this to avoid bogus arm OABI complaints */
62 	union {
63 		/* index into fixed buffers, if used */
64 		__u16	buf_index;
65 		/* for grouped buffer selection */
66 		__u16	buf_group;
67 	} __attribute__((packed));
68 	/* personality to use, if used */
69 	__u16	personality;
70 	union {
71 		__s32	splice_fd_in;
72 		__u32	file_index;
73 		struct {
74 			__u16	notification_idx;
75 			__u16	addr_len;
76 		};
77 	};
78 	union {
79 		struct {
80 			__u64	addr3;
81 			__u64	__pad2[1];
82 		};
83 		/*
84 		 * If the ring is initialized with IORING_SETUP_SQE128, then
85 		 * this field is used for 80 bytes of arbitrary command data
86 		 */
87 		__u8	cmd[0];
88 	};
89 };
90 
91 /*
92  * If sqe->file_index is set to this for opcodes that instantiate a new
93  * direct descriptor (like openat/openat2/accept), then io_uring will allocate
94  * an available direct descriptor instead of having the application pass one
95  * in. The picked direct descriptor will be returned in cqe->res, or -ENFILE
96  * if the space is full.
97  */
98 #define IORING_FILE_INDEX_ALLOC		(~0U)
99 
100 enum {
101 	IOSQE_FIXED_FILE_BIT,
102 	IOSQE_IO_DRAIN_BIT,
103 	IOSQE_IO_LINK_BIT,
104 	IOSQE_IO_HARDLINK_BIT,
105 	IOSQE_ASYNC_BIT,
106 	IOSQE_BUFFER_SELECT_BIT,
107 	IOSQE_CQE_SKIP_SUCCESS_BIT,
108 };
109 
110 /*
111  * sqe->flags
112  */
113 /* use fixed fileset */
114 #define IOSQE_FIXED_FILE	(1U << IOSQE_FIXED_FILE_BIT)
115 /* issue after inflight IO */
116 #define IOSQE_IO_DRAIN		(1U << IOSQE_IO_DRAIN_BIT)
117 /* links next sqe */
118 #define IOSQE_IO_LINK		(1U << IOSQE_IO_LINK_BIT)
119 /* like LINK, but stronger */
120 #define IOSQE_IO_HARDLINK	(1U << IOSQE_IO_HARDLINK_BIT)
121 /* always go async */
122 #define IOSQE_ASYNC		(1U << IOSQE_ASYNC_BIT)
123 /* select buffer from sqe->buf_group */
124 #define IOSQE_BUFFER_SELECT	(1U << IOSQE_BUFFER_SELECT_BIT)
125 /* don't post CQE if request succeeded */
126 #define IOSQE_CQE_SKIP_SUCCESS	(1U << IOSQE_CQE_SKIP_SUCCESS_BIT)
127 
128 /*
129  * io_uring_setup() flags
130  */
131 #define IORING_SETUP_IOPOLL	(1U << 0)	/* io_context is polled */
132 #define IORING_SETUP_SQPOLL	(1U << 1)	/* SQ poll thread */
133 #define IORING_SETUP_SQ_AFF	(1U << 2)	/* sq_thread_cpu is valid */
134 #define IORING_SETUP_CQSIZE	(1U << 3)	/* app defines CQ size */
135 #define IORING_SETUP_CLAMP	(1U << 4)	/* clamp SQ/CQ ring sizes */
136 #define IORING_SETUP_ATTACH_WQ	(1U << 5)	/* attach to existing wq */
137 #define IORING_SETUP_R_DISABLED	(1U << 6)	/* start with ring disabled */
138 #define IORING_SETUP_SUBMIT_ALL	(1U << 7)	/* continue submit on error */
139 /*
140  * Cooperative task running. When requests complete, they often require
141  * forcing the submitter to transition to the kernel to complete. If this
142  * flag is set, work will be done when the task transitions anyway, rather
143  * than force an inter-processor interrupt reschedule. This avoids interrupting
144  * a task running in userspace, and saves an IPI.
145  */
146 #define IORING_SETUP_COOP_TASKRUN	(1U << 8)
147 /*
148  * If COOP_TASKRUN is set, get notified if task work is available for
149  * running and a kernel transition would be needed to run it. This sets
150  * IORING_SQ_TASKRUN in the sq ring flags. Not valid with COOP_TASKRUN.
151  */
152 #define IORING_SETUP_TASKRUN_FLAG	(1U << 9)
153 #define IORING_SETUP_SQE128		(1U << 10) /* SQEs are 128 byte */
154 #define IORING_SETUP_CQE32		(1U << 11) /* CQEs are 32 byte */
155 /*
156  * Only one task is allowed to submit requests
157  */
158 #define IORING_SETUP_SINGLE_ISSUER	(1U << 12)
159 
160 enum io_uring_op {
161 	IORING_OP_NOP,
162 	IORING_OP_READV,
163 	IORING_OP_WRITEV,
164 	IORING_OP_FSYNC,
165 	IORING_OP_READ_FIXED,
166 	IORING_OP_WRITE_FIXED,
167 	IORING_OP_POLL_ADD,
168 	IORING_OP_POLL_REMOVE,
169 	IORING_OP_SYNC_FILE_RANGE,
170 	IORING_OP_SENDMSG,
171 	IORING_OP_RECVMSG,
172 	IORING_OP_TIMEOUT,
173 	IORING_OP_TIMEOUT_REMOVE,
174 	IORING_OP_ACCEPT,
175 	IORING_OP_ASYNC_CANCEL,
176 	IORING_OP_LINK_TIMEOUT,
177 	IORING_OP_CONNECT,
178 	IORING_OP_FALLOCATE,
179 	IORING_OP_OPENAT,
180 	IORING_OP_CLOSE,
181 	IORING_OP_RSRC_UPDATE,
182 	IORING_OP_FILES_UPDATE = IORING_OP_RSRC_UPDATE,
183 	IORING_OP_STATX,
184 	IORING_OP_READ,
185 	IORING_OP_WRITE,
186 	IORING_OP_FADVISE,
187 	IORING_OP_MADVISE,
188 	IORING_OP_SEND,
189 	IORING_OP_RECV,
190 	IORING_OP_OPENAT2,
191 	IORING_OP_EPOLL_CTL,
192 	IORING_OP_SPLICE,
193 	IORING_OP_PROVIDE_BUFFERS,
194 	IORING_OP_REMOVE_BUFFERS,
195 	IORING_OP_TEE,
196 	IORING_OP_SHUTDOWN,
197 	IORING_OP_RENAMEAT,
198 	IORING_OP_UNLINKAT,
199 	IORING_OP_MKDIRAT,
200 	IORING_OP_SYMLINKAT,
201 	IORING_OP_LINKAT,
202 	IORING_OP_MSG_RING,
203 	IORING_OP_FSETXATTR,
204 	IORING_OP_SETXATTR,
205 	IORING_OP_FGETXATTR,
206 	IORING_OP_GETXATTR,
207 	IORING_OP_SOCKET,
208 	IORING_OP_URING_CMD,
209 	IORING_OP_SENDZC_NOTIF,
210 
211 	/* this goes last, obviously */
212 	IORING_OP_LAST,
213 };
214 
215 /*
216  * sqe->fsync_flags
217  */
218 #define IORING_FSYNC_DATASYNC	(1U << 0)
219 
220 /*
221  * sqe->timeout_flags
222  */
223 #define IORING_TIMEOUT_ABS		(1U << 0)
224 #define IORING_TIMEOUT_UPDATE		(1U << 1)
225 #define IORING_TIMEOUT_BOOTTIME		(1U << 2)
226 #define IORING_TIMEOUT_REALTIME		(1U << 3)
227 #define IORING_LINK_TIMEOUT_UPDATE	(1U << 4)
228 #define IORING_TIMEOUT_ETIME_SUCCESS	(1U << 5)
229 #define IORING_TIMEOUT_CLOCK_MASK	(IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME)
230 #define IORING_TIMEOUT_UPDATE_MASK	(IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE)
231 
232 /*
233  * sqe->splice_flags
234  * extends splice(2) flags
235  */
236 #define SPLICE_F_FD_IN_FIXED	(1U << 31) /* the last bit of __u32 */
237 
238 /*
239  * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the
240  * command flags for POLL_ADD are stored in sqe->len.
241  *
242  * IORING_POLL_ADD_MULTI	Multishot poll. Sets IORING_CQE_F_MORE if
243  *				the poll handler will continue to report
244  *				CQEs on behalf of the same SQE.
245  *
246  * IORING_POLL_UPDATE		Update existing poll request, matching
247  *				sqe->addr as the old user_data field.
248  *
249  * IORING_POLL_LEVEL		Level triggered poll.
250  */
251 #define IORING_POLL_ADD_MULTI	(1U << 0)
252 #define IORING_POLL_UPDATE_EVENTS	(1U << 1)
253 #define IORING_POLL_UPDATE_USER_DATA	(1U << 2)
254 #define IORING_POLL_ADD_LEVEL		(1U << 3)
255 
256 /*
257  * ASYNC_CANCEL flags.
258  *
259  * IORING_ASYNC_CANCEL_ALL	Cancel all requests that match the given key
260  * IORING_ASYNC_CANCEL_FD	Key off 'fd' for cancelation rather than the
261  *				request 'user_data'
262  * IORING_ASYNC_CANCEL_ANY	Match any request
263  * IORING_ASYNC_CANCEL_FD_FIXED	'fd' passed in is a fixed descriptor
264  */
265 #define IORING_ASYNC_CANCEL_ALL	(1U << 0)
266 #define IORING_ASYNC_CANCEL_FD	(1U << 1)
267 #define IORING_ASYNC_CANCEL_ANY	(1U << 2)
268 #define IORING_ASYNC_CANCEL_FD_FIXED	(1U << 3)
269 
270 /*
271  * send/sendmsg and recv/recvmsg flags (sqe->ioprio)
272  *
273  * IORING_RECVSEND_POLL_FIRST	If set, instead of first attempting to send
274  *				or receive and arm poll if that yields an
275  *				-EAGAIN result, arm poll upfront and skip
276  *				the initial transfer attempt.
277  *
278  * IORING_RECV_MULTISHOT	Multishot recv. Sets IORING_CQE_F_MORE if
279  *				the handler will continue to report
280  *				CQEs on behalf of the same SQE.
281  *
282  * IORING_RECVSEND_FIXED_BUF	Use registered buffers, the index is stored in
283  *				the buf_index field.
284  *
285  * IORING_RECVSEND_NOTIF_FLUSH	Flush a notification after a successful
286  *				successful. Only for zerocopy sends.
287  */
288 #define IORING_RECVSEND_POLL_FIRST	(1U << 0)
289 #define IORING_RECV_MULTISHOT		(1U << 1)
290 #define IORING_RECVSEND_FIXED_BUF	(1U << 2)
291 #define IORING_RECVSEND_NOTIF_FLUSH	(1U << 3)
292 
293 /*
294  * accept flags stored in sqe->ioprio
295  */
296 #define IORING_ACCEPT_MULTISHOT	(1U << 0)
297 
298 
299 /*
300  * IORING_OP_RSRC_UPDATE flags
301  */
302 enum {
303 	IORING_RSRC_UPDATE_FILES,
304 	IORING_RSRC_UPDATE_NOTIF,
305 };
306 
307 /*
308  * IORING_OP_MSG_RING command types, stored in sqe->addr
309  */
310 enum {
311 	IORING_MSG_DATA,	/* pass sqe->len as 'res' and off as user_data */
312 	IORING_MSG_SEND_FD,	/* send a registered fd to another ring */
313 };
314 
315 /*
316  * IORING_OP_MSG_RING flags (sqe->msg_ring_flags)
317  *
318  * IORING_MSG_RING_CQE_SKIP	Don't post a CQE to the target ring. Not
319  *				applicable for IORING_MSG_DATA, obviously.
320  */
321 #define IORING_MSG_RING_CQE_SKIP	(1U << 0)
322 
323 /*
324  * IO completion data structure (Completion Queue Entry)
325  */
326 struct io_uring_cqe {
327 	__u64	user_data;	/* sqe->data submission passed back */
328 	__s32	res;		/* result code for this event */
329 	__u32	flags;
330 
331 	/*
332 	 * If the ring is initialized with IORING_SETUP_CQE32, then this field
333 	 * contains 16-bytes of padding, doubling the size of the CQE.
334 	 */
335 	__u64 big_cqe[];
336 };
337 
338 /*
339  * cqe->flags
340  *
341  * IORING_CQE_F_BUFFER	If set, the upper 16 bits are the buffer ID
342  * IORING_CQE_F_MORE	If set, parent SQE will generate more CQE entries
343  * IORING_CQE_F_SOCK_NONEMPTY	If set, more data to read after socket recv
344  */
345 #define IORING_CQE_F_BUFFER		(1U << 0)
346 #define IORING_CQE_F_MORE		(1U << 1)
347 #define IORING_CQE_F_SOCK_NONEMPTY	(1U << 2)
348 
349 enum {
350 	IORING_CQE_BUFFER_SHIFT		= 16,
351 };
352 
353 /*
354  * Magic offsets for the application to mmap the data it needs
355  */
356 #define IORING_OFF_SQ_RING		0ULL
357 #define IORING_OFF_CQ_RING		0x8000000ULL
358 #define IORING_OFF_SQES			0x10000000ULL
359 
360 /*
361  * Filled with the offset for mmap(2)
362  */
363 struct io_sqring_offsets {
364 	__u32 head;
365 	__u32 tail;
366 	__u32 ring_mask;
367 	__u32 ring_entries;
368 	__u32 flags;
369 	__u32 dropped;
370 	__u32 array;
371 	__u32 resv1;
372 	__u64 resv2;
373 };
374 
375 /*
376  * sq_ring->flags
377  */
378 #define IORING_SQ_NEED_WAKEUP	(1U << 0) /* needs io_uring_enter wakeup */
379 #define IORING_SQ_CQ_OVERFLOW	(1U << 1) /* CQ ring is overflown */
380 #define IORING_SQ_TASKRUN	(1U << 2) /* task should enter the kernel */
381 
382 struct io_cqring_offsets {
383 	__u32 head;
384 	__u32 tail;
385 	__u32 ring_mask;
386 	__u32 ring_entries;
387 	__u32 overflow;
388 	__u32 cqes;
389 	__u32 flags;
390 	__u32 resv1;
391 	__u64 resv2;
392 };
393 
394 /*
395  * cq_ring->flags
396  */
397 
398 /* disable eventfd notifications */
399 #define IORING_CQ_EVENTFD_DISABLED	(1U << 0)
400 
401 /*
402  * io_uring_enter(2) flags
403  */
404 #define IORING_ENTER_GETEVENTS		(1U << 0)
405 #define IORING_ENTER_SQ_WAKEUP		(1U << 1)
406 #define IORING_ENTER_SQ_WAIT		(1U << 2)
407 #define IORING_ENTER_EXT_ARG		(1U << 3)
408 #define IORING_ENTER_REGISTERED_RING	(1U << 4)
409 
410 /*
411  * Passed in for io_uring_setup(2). Copied back with updated info on success
412  */
413 struct io_uring_params {
414 	__u32 sq_entries;
415 	__u32 cq_entries;
416 	__u32 flags;
417 	__u32 sq_thread_cpu;
418 	__u32 sq_thread_idle;
419 	__u32 features;
420 	__u32 wq_fd;
421 	__u32 resv[3];
422 	struct io_sqring_offsets sq_off;
423 	struct io_cqring_offsets cq_off;
424 };
425 
426 /*
427  * io_uring_params->features flags
428  */
429 #define IORING_FEAT_SINGLE_MMAP		(1U << 0)
430 #define IORING_FEAT_NODROP		(1U << 1)
431 #define IORING_FEAT_SUBMIT_STABLE	(1U << 2)
432 #define IORING_FEAT_RW_CUR_POS		(1U << 3)
433 #define IORING_FEAT_CUR_PERSONALITY	(1U << 4)
434 #define IORING_FEAT_FAST_POLL		(1U << 5)
435 #define IORING_FEAT_POLL_32BITS 	(1U << 6)
436 #define IORING_FEAT_SQPOLL_NONFIXED	(1U << 7)
437 #define IORING_FEAT_EXT_ARG		(1U << 8)
438 #define IORING_FEAT_NATIVE_WORKERS	(1U << 9)
439 #define IORING_FEAT_RSRC_TAGS		(1U << 10)
440 #define IORING_FEAT_CQE_SKIP		(1U << 11)
441 #define IORING_FEAT_LINKED_FILE		(1U << 12)
442 
443 /*
444  * io_uring_register(2) opcodes and arguments
445  */
446 enum {
447 	IORING_REGISTER_BUFFERS			= 0,
448 	IORING_UNREGISTER_BUFFERS		= 1,
449 	IORING_REGISTER_FILES			= 2,
450 	IORING_UNREGISTER_FILES			= 3,
451 	IORING_REGISTER_EVENTFD			= 4,
452 	IORING_UNREGISTER_EVENTFD		= 5,
453 	IORING_REGISTER_FILES_UPDATE		= 6,
454 	IORING_REGISTER_EVENTFD_ASYNC		= 7,
455 	IORING_REGISTER_PROBE			= 8,
456 	IORING_REGISTER_PERSONALITY		= 9,
457 	IORING_UNREGISTER_PERSONALITY		= 10,
458 	IORING_REGISTER_RESTRICTIONS		= 11,
459 	IORING_REGISTER_ENABLE_RINGS		= 12,
460 
461 	/* extended with tagging */
462 	IORING_REGISTER_FILES2			= 13,
463 	IORING_REGISTER_FILES_UPDATE2		= 14,
464 	IORING_REGISTER_BUFFERS2		= 15,
465 	IORING_REGISTER_BUFFERS_UPDATE		= 16,
466 
467 	/* set/clear io-wq thread affinities */
468 	IORING_REGISTER_IOWQ_AFF		= 17,
469 	IORING_UNREGISTER_IOWQ_AFF		= 18,
470 
471 	/* set/get max number of io-wq workers */
472 	IORING_REGISTER_IOWQ_MAX_WORKERS	= 19,
473 
474 	/* register/unregister io_uring fd with the ring */
475 	IORING_REGISTER_RING_FDS		= 20,
476 	IORING_UNREGISTER_RING_FDS		= 21,
477 
478 	/* register ring based provide buffer group */
479 	IORING_REGISTER_PBUF_RING		= 22,
480 	IORING_UNREGISTER_PBUF_RING		= 23,
481 
482 	/* sync cancelation API */
483 	IORING_REGISTER_SYNC_CANCEL		= 24,
484 
485 	/* register a range of fixed file slots for automatic slot allocation */
486 	IORING_REGISTER_FILE_ALLOC_RANGE	= 25,
487 
488 	/* zerocopy notification API */
489 	IORING_REGISTER_NOTIFIERS		= 26,
490 	IORING_UNREGISTER_NOTIFIERS		= 27,
491 
492 	/* this goes last */
493 	IORING_REGISTER_LAST
494 };
495 
496 /* io-wq worker categories */
497 enum {
498 	IO_WQ_BOUND,
499 	IO_WQ_UNBOUND,
500 };
501 
502 /* deprecated, see struct io_uring_rsrc_update */
503 struct io_uring_files_update {
504 	__u32 offset;
505 	__u32 resv;
506 	__aligned_u64 /* __s32 * */ fds;
507 };
508 
509 /*
510  * Register a fully sparse file space, rather than pass in an array of all
511  * -1 file descriptors.
512  */
513 #define IORING_RSRC_REGISTER_SPARSE	(1U << 0)
514 
515 struct io_uring_rsrc_register {
516 	__u32 nr;
517 	__u32 flags;
518 	__u64 resv2;
519 	__aligned_u64 data;
520 	__aligned_u64 tags;
521 };
522 
523 struct io_uring_rsrc_update {
524 	__u32 offset;
525 	__u32 resv;
526 	__aligned_u64 data;
527 };
528 
529 struct io_uring_rsrc_update2 {
530 	__u32 offset;
531 	__u32 resv;
532 	__aligned_u64 data;
533 	__aligned_u64 tags;
534 	__u32 nr;
535 	__u32 resv2;
536 };
537 
538 struct io_uring_notification_slot {
539 	__u64 tag;
540 	__u64 resv[3];
541 };
542 
543 struct io_uring_notification_register {
544 	__u32 nr_slots;
545 	__u32 resv;
546 	__u64 resv2;
547 	__u64 data;
548 	__u64 resv3;
549 };
550 
551 /* Skip updating fd indexes set to this value in the fd table */
552 #define IORING_REGISTER_FILES_SKIP	(-2)
553 
554 #define IO_URING_OP_SUPPORTED	(1U << 0)
555 
556 struct io_uring_probe_op {
557 	__u8 op;
558 	__u8 resv;
559 	__u16 flags;	/* IO_URING_OP_* flags */
560 	__u32 resv2;
561 };
562 
563 struct io_uring_probe {
564 	__u8 last_op;	/* last opcode supported */
565 	__u8 ops_len;	/* length of ops[] array below */
566 	__u16 resv;
567 	__u32 resv2[3];
568 	struct io_uring_probe_op ops[];
569 };
570 
571 struct io_uring_restriction {
572 	__u16 opcode;
573 	union {
574 		__u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
575 		__u8 sqe_op;      /* IORING_RESTRICTION_SQE_OP */
576 		__u8 sqe_flags;   /* IORING_RESTRICTION_SQE_FLAGS_* */
577 	};
578 	__u8 resv;
579 	__u32 resv2[3];
580 };
581 
582 struct io_uring_buf {
583 	__u64	addr;
584 	__u32	len;
585 	__u16	bid;
586 	__u16	resv;
587 };
588 
589 struct io_uring_buf_ring {
590 	union {
591 		/*
592 		 * To avoid spilling into more pages than we need to, the
593 		 * ring tail is overlaid with the io_uring_buf->resv field.
594 		 */
595 		struct {
596 			__u64	resv1;
597 			__u32	resv2;
598 			__u16	resv3;
599 			__u16	tail;
600 		};
601 		struct io_uring_buf	bufs[0];
602 	};
603 };
604 
605 /* argument for IORING_(UN)REGISTER_PBUF_RING */
606 struct io_uring_buf_reg {
607 	__u64	ring_addr;
608 	__u32	ring_entries;
609 	__u16	bgid;
610 	__u16	pad;
611 	__u64	resv[3];
612 };
613 
614 /*
615  * io_uring_restriction->opcode values
616  */
617 enum {
618 	/* Allow an io_uring_register(2) opcode */
619 	IORING_RESTRICTION_REGISTER_OP		= 0,
620 
621 	/* Allow an sqe opcode */
622 	IORING_RESTRICTION_SQE_OP		= 1,
623 
624 	/* Allow sqe flags */
625 	IORING_RESTRICTION_SQE_FLAGS_ALLOWED	= 2,
626 
627 	/* Require sqe flags (these flags must be set on each submission) */
628 	IORING_RESTRICTION_SQE_FLAGS_REQUIRED	= 3,
629 
630 	IORING_RESTRICTION_LAST
631 };
632 
633 struct io_uring_getevents_arg {
634 	__u64	sigmask;
635 	__u32	sigmask_sz;
636 	__u32	pad;
637 	__u64	ts;
638 };
639 
640 /*
641  * Argument for IORING_REGISTER_SYNC_CANCEL
642  */
643 struct io_uring_sync_cancel_reg {
644 	__u64				addr;
645 	__s32				fd;
646 	__u32				flags;
647 	struct __kernel_timespec	timeout;
648 	__u64				pad[4];
649 };
650 
651 /*
652  * Argument for IORING_REGISTER_FILE_ALLOC_RANGE
653  * The range is specified as [off, off + len)
654  */
655 struct io_uring_file_index_range {
656 	__u32	off;
657 	__u32	len;
658 	__u64	resv;
659 };
660 
661 struct io_uring_recvmsg_out {
662 	__u32 namelen;
663 	__u32 controllen;
664 	__u32 payloadlen;
665 	__u32 flags;
666 };
667 
668 #ifdef __cplusplus
669 }
670 #endif
671 
672 #endif
673