xref: /openbmc/linux/include/uapi/linux/io_uring.h (revision a97126265dfe10d3321c0fde4708a6cea49b19ed)
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 /*
16  * IO submission data structure (Submission Queue Entry)
17  */
18 struct io_uring_sqe {
19 	__u8	opcode;		/* type of operation for this sqe */
20 	__u8	flags;		/* IOSQE_ flags */
21 	__u16	ioprio;		/* ioprio for the request */
22 	__s32	fd;		/* file descriptor to do IO on */
23 	union {
24 		__u64	off;	/* offset into file */
25 		__u64	addr2;
26 		struct {
27 			__u32	cmd_op;
28 			__u32	__pad1;
29 		};
30 	};
31 	union {
32 		__u64	addr;	/* pointer to buffer or iovecs */
33 		__u64	splice_off_in;
34 	};
35 	__u32	len;		/* buffer size or number of iovecs */
36 	union {
37 		__kernel_rwf_t	rw_flags;
38 		__u32		fsync_flags;
39 		__u16		poll_events;	/* compatibility */
40 		__u32		poll32_events;	/* word-reversed for BE */
41 		__u32		sync_range_flags;
42 		__u32		msg_flags;
43 		__u32		timeout_flags;
44 		__u32		accept_flags;
45 		__u32		cancel_flags;
46 		__u32		open_flags;
47 		__u32		statx_flags;
48 		__u32		fadvise_advice;
49 		__u32		splice_flags;
50 		__u32		rename_flags;
51 		__u32		unlink_flags;
52 		__u32		hardlink_flags;
53 		__u32		xattr_flags;
54 		__u32		msg_ring_flags;
55 	};
56 	__u64	user_data;	/* data to be passed back at completion time */
57 	/* pack this to avoid bogus arm OABI complaints */
58 	union {
59 		/* index into fixed buffers, if used */
60 		__u16	buf_index;
61 		/* for grouped buffer selection */
62 		__u16	buf_group;
63 	} __attribute__((packed));
64 	/* personality to use, if used */
65 	__u16	personality;
66 	union {
67 		__s32	splice_fd_in;
68 		__u32	file_index;
69 		struct {
70 			__u16	notification_idx;
71 			__u16	addr_len;
72 		};
73 	};
74 	union {
75 		struct {
76 			__u64	addr3;
77 			__u64	__pad2[1];
78 		};
79 		/*
80 		 * If the ring is initialized with IORING_SETUP_SQE128, then
81 		 * this field is used for 80 bytes of arbitrary command data
82 		 */
83 		__u8	cmd[0];
84 	};
85 };
86 
87 /*
88  * If sqe->file_index is set to this for opcodes that instantiate a new
89  * direct descriptor (like openat/openat2/accept), then io_uring will allocate
90  * an available direct descriptor instead of having the application pass one
91  * in. The picked direct descriptor will be returned in cqe->res, or -ENFILE
92  * if the space is full.
93  */
94 #define IORING_FILE_INDEX_ALLOC		(~0U)
95 
96 enum {
97 	IOSQE_FIXED_FILE_BIT,
98 	IOSQE_IO_DRAIN_BIT,
99 	IOSQE_IO_LINK_BIT,
100 	IOSQE_IO_HARDLINK_BIT,
101 	IOSQE_ASYNC_BIT,
102 	IOSQE_BUFFER_SELECT_BIT,
103 	IOSQE_CQE_SKIP_SUCCESS_BIT,
104 };
105 
106 /*
107  * sqe->flags
108  */
109 /* use fixed fileset */
110 #define IOSQE_FIXED_FILE	(1U << IOSQE_FIXED_FILE_BIT)
111 /* issue after inflight IO */
112 #define IOSQE_IO_DRAIN		(1U << IOSQE_IO_DRAIN_BIT)
113 /* links next sqe */
114 #define IOSQE_IO_LINK		(1U << IOSQE_IO_LINK_BIT)
115 /* like LINK, but stronger */
116 #define IOSQE_IO_HARDLINK	(1U << IOSQE_IO_HARDLINK_BIT)
117 /* always go async */
118 #define IOSQE_ASYNC		(1U << IOSQE_ASYNC_BIT)
119 /* select buffer from sqe->buf_group */
120 #define IOSQE_BUFFER_SELECT	(1U << IOSQE_BUFFER_SELECT_BIT)
121 /* don't post CQE if request succeeded */
122 #define IOSQE_CQE_SKIP_SUCCESS	(1U << IOSQE_CQE_SKIP_SUCCESS_BIT)
123 
124 /*
125  * io_uring_setup() flags
126  */
127 #define IORING_SETUP_IOPOLL	(1U << 0)	/* io_context is polled */
128 #define IORING_SETUP_SQPOLL	(1U << 1)	/* SQ poll thread */
129 #define IORING_SETUP_SQ_AFF	(1U << 2)	/* sq_thread_cpu is valid */
130 #define IORING_SETUP_CQSIZE	(1U << 3)	/* app defines CQ size */
131 #define IORING_SETUP_CLAMP	(1U << 4)	/* clamp SQ/CQ ring sizes */
132 #define IORING_SETUP_ATTACH_WQ	(1U << 5)	/* attach to existing wq */
133 #define IORING_SETUP_R_DISABLED	(1U << 6)	/* start with ring disabled */
134 #define IORING_SETUP_SUBMIT_ALL	(1U << 7)	/* continue submit on error */
135 /*
136  * Cooperative task running. When requests complete, they often require
137  * forcing the submitter to transition to the kernel to complete. If this
138  * flag is set, work will be done when the task transitions anyway, rather
139  * than force an inter-processor interrupt reschedule. This avoids interrupting
140  * a task running in userspace, and saves an IPI.
141  */
142 #define IORING_SETUP_COOP_TASKRUN	(1U << 8)
143 /*
144  * If COOP_TASKRUN is set, get notified if task work is available for
145  * running and a kernel transition would be needed to run it. This sets
146  * IORING_SQ_TASKRUN in the sq ring flags. Not valid with COOP_TASKRUN.
147  */
148 #define IORING_SETUP_TASKRUN_FLAG	(1U << 9)
149 #define IORING_SETUP_SQE128		(1U << 10) /* SQEs are 128 byte */
150 #define IORING_SETUP_CQE32		(1U << 11) /* CQEs are 32 byte */
151 /*
152  * Only one task is allowed to submit requests
153  */
154 #define IORING_SETUP_SINGLE_ISSUER	(1U << 12)
155 
156 enum io_uring_op {
157 	IORING_OP_NOP,
158 	IORING_OP_READV,
159 	IORING_OP_WRITEV,
160 	IORING_OP_FSYNC,
161 	IORING_OP_READ_FIXED,
162 	IORING_OP_WRITE_FIXED,
163 	IORING_OP_POLL_ADD,
164 	IORING_OP_POLL_REMOVE,
165 	IORING_OP_SYNC_FILE_RANGE,
166 	IORING_OP_SENDMSG,
167 	IORING_OP_RECVMSG,
168 	IORING_OP_TIMEOUT,
169 	IORING_OP_TIMEOUT_REMOVE,
170 	IORING_OP_ACCEPT,
171 	IORING_OP_ASYNC_CANCEL,
172 	IORING_OP_LINK_TIMEOUT,
173 	IORING_OP_CONNECT,
174 	IORING_OP_FALLOCATE,
175 	IORING_OP_OPENAT,
176 	IORING_OP_CLOSE,
177 	IORING_OP_RSRC_UPDATE,
178 	IORING_OP_FILES_UPDATE = IORING_OP_RSRC_UPDATE,
179 	IORING_OP_STATX,
180 	IORING_OP_READ,
181 	IORING_OP_WRITE,
182 	IORING_OP_FADVISE,
183 	IORING_OP_MADVISE,
184 	IORING_OP_SEND,
185 	IORING_OP_RECV,
186 	IORING_OP_OPENAT2,
187 	IORING_OP_EPOLL_CTL,
188 	IORING_OP_SPLICE,
189 	IORING_OP_PROVIDE_BUFFERS,
190 	IORING_OP_REMOVE_BUFFERS,
191 	IORING_OP_TEE,
192 	IORING_OP_SHUTDOWN,
193 	IORING_OP_RENAMEAT,
194 	IORING_OP_UNLINKAT,
195 	IORING_OP_MKDIRAT,
196 	IORING_OP_SYMLINKAT,
197 	IORING_OP_LINKAT,
198 	IORING_OP_MSG_RING,
199 	IORING_OP_FSETXATTR,
200 	IORING_OP_SETXATTR,
201 	IORING_OP_FGETXATTR,
202 	IORING_OP_GETXATTR,
203 	IORING_OP_SOCKET,
204 	IORING_OP_URING_CMD,
205 	IORING_OP_SENDZC_NOTIF,
206 
207 	/* this goes last, obviously */
208 	IORING_OP_LAST,
209 };
210 
211 /*
212  * sqe->fsync_flags
213  */
214 #define IORING_FSYNC_DATASYNC	(1U << 0)
215 
216 /*
217  * sqe->timeout_flags
218  */
219 #define IORING_TIMEOUT_ABS		(1U << 0)
220 #define IORING_TIMEOUT_UPDATE		(1U << 1)
221 #define IORING_TIMEOUT_BOOTTIME		(1U << 2)
222 #define IORING_TIMEOUT_REALTIME		(1U << 3)
223 #define IORING_LINK_TIMEOUT_UPDATE	(1U << 4)
224 #define IORING_TIMEOUT_ETIME_SUCCESS	(1U << 5)
225 #define IORING_TIMEOUT_CLOCK_MASK	(IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME)
226 #define IORING_TIMEOUT_UPDATE_MASK	(IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE)
227 
228 /*
229  * sqe->splice_flags
230  * extends splice(2) flags
231  */
232 #define SPLICE_F_FD_IN_FIXED	(1U << 31) /* the last bit of __u32 */
233 
234 /*
235  * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the
236  * command flags for POLL_ADD are stored in sqe->len.
237  *
238  * IORING_POLL_ADD_MULTI	Multishot poll. Sets IORING_CQE_F_MORE if
239  *				the poll handler will continue to report
240  *				CQEs on behalf of the same SQE.
241  *
242  * IORING_POLL_UPDATE		Update existing poll request, matching
243  *				sqe->addr as the old user_data field.
244  *
245  * IORING_POLL_LEVEL		Level triggered poll.
246  */
247 #define IORING_POLL_ADD_MULTI	(1U << 0)
248 #define IORING_POLL_UPDATE_EVENTS	(1U << 1)
249 #define IORING_POLL_UPDATE_USER_DATA	(1U << 2)
250 #define IORING_POLL_ADD_LEVEL		(1U << 3)
251 
252 /*
253  * ASYNC_CANCEL flags.
254  *
255  * IORING_ASYNC_CANCEL_ALL	Cancel all requests that match the given key
256  * IORING_ASYNC_CANCEL_FD	Key off 'fd' for cancelation rather than the
257  *				request 'user_data'
258  * IORING_ASYNC_CANCEL_ANY	Match any request
259  * IORING_ASYNC_CANCEL_FD_FIXED	'fd' passed in is a fixed descriptor
260  */
261 #define IORING_ASYNC_CANCEL_ALL	(1U << 0)
262 #define IORING_ASYNC_CANCEL_FD	(1U << 1)
263 #define IORING_ASYNC_CANCEL_ANY	(1U << 2)
264 #define IORING_ASYNC_CANCEL_FD_FIXED	(1U << 3)
265 
266 /*
267  * send/sendmsg and recv/recvmsg flags (sqe->ioprio)
268  *
269  * IORING_RECVSEND_POLL_FIRST	If set, instead of first attempting to send
270  *				or receive and arm poll if that yields an
271  *				-EAGAIN result, arm poll upfront and skip
272  *				the initial transfer attempt.
273  *
274  * IORING_RECV_MULTISHOT	Multishot recv. Sets IORING_CQE_F_MORE if
275  *				the handler will continue to report
276  *				CQEs on behalf of the same SQE.
277  *
278  * IORING_RECVSEND_FIXED_BUF	Use registered buffers, the index is stored in
279  *				the buf_index field.
280  *
281  * IORING_RECVSEND_NOTIF_FLUSH	Flush a notification after a successful
282  *				successful. Only for zerocopy sends.
283  */
284 #define IORING_RECVSEND_POLL_FIRST	(1U << 0)
285 #define IORING_RECV_MULTISHOT		(1U << 1)
286 #define IORING_RECVSEND_FIXED_BUF	(1U << 2)
287 #define IORING_RECVSEND_NOTIF_FLUSH	(1U << 3)
288 
289 /*
290  * accept flags stored in sqe->ioprio
291  */
292 #define IORING_ACCEPT_MULTISHOT	(1U << 0)
293 
294 
295 /*
296  * IORING_OP_RSRC_UPDATE flags
297  */
298 enum {
299 	IORING_RSRC_UPDATE_FILES,
300 	IORING_RSRC_UPDATE_NOTIF,
301 };
302 
303 /*
304  * IORING_OP_MSG_RING command types, stored in sqe->addr
305  */
306 enum {
307 	IORING_MSG_DATA,	/* pass sqe->len as 'res' and off as user_data */
308 	IORING_MSG_SEND_FD,	/* send a registered fd to another ring */
309 };
310 
311 /*
312  * IORING_OP_MSG_RING flags (sqe->msg_ring_flags)
313  *
314  * IORING_MSG_RING_CQE_SKIP	Don't post a CQE to the target ring. Not
315  *				applicable for IORING_MSG_DATA, obviously.
316  */
317 #define IORING_MSG_RING_CQE_SKIP	(1U << 0)
318 
319 /*
320  * IO completion data structure (Completion Queue Entry)
321  */
322 struct io_uring_cqe {
323 	__u64	user_data;	/* sqe->data submission passed back */
324 	__s32	res;		/* result code for this event */
325 	__u32	flags;
326 
327 	/*
328 	 * If the ring is initialized with IORING_SETUP_CQE32, then this field
329 	 * contains 16-bytes of padding, doubling the size of the CQE.
330 	 */
331 	__u64 big_cqe[];
332 };
333 
334 /*
335  * cqe->flags
336  *
337  * IORING_CQE_F_BUFFER	If set, the upper 16 bits are the buffer ID
338  * IORING_CQE_F_MORE	If set, parent SQE will generate more CQE entries
339  * IORING_CQE_F_SOCK_NONEMPTY	If set, more data to read after socket recv
340  */
341 #define IORING_CQE_F_BUFFER		(1U << 0)
342 #define IORING_CQE_F_MORE		(1U << 1)
343 #define IORING_CQE_F_SOCK_NONEMPTY	(1U << 2)
344 
345 enum {
346 	IORING_CQE_BUFFER_SHIFT		= 16,
347 };
348 
349 /*
350  * Magic offsets for the application to mmap the data it needs
351  */
352 #define IORING_OFF_SQ_RING		0ULL
353 #define IORING_OFF_CQ_RING		0x8000000ULL
354 #define IORING_OFF_SQES			0x10000000ULL
355 
356 /*
357  * Filled with the offset for mmap(2)
358  */
359 struct io_sqring_offsets {
360 	__u32 head;
361 	__u32 tail;
362 	__u32 ring_mask;
363 	__u32 ring_entries;
364 	__u32 flags;
365 	__u32 dropped;
366 	__u32 array;
367 	__u32 resv1;
368 	__u64 resv2;
369 };
370 
371 /*
372  * sq_ring->flags
373  */
374 #define IORING_SQ_NEED_WAKEUP	(1U << 0) /* needs io_uring_enter wakeup */
375 #define IORING_SQ_CQ_OVERFLOW	(1U << 1) /* CQ ring is overflown */
376 #define IORING_SQ_TASKRUN	(1U << 2) /* task should enter the kernel */
377 
378 struct io_cqring_offsets {
379 	__u32 head;
380 	__u32 tail;
381 	__u32 ring_mask;
382 	__u32 ring_entries;
383 	__u32 overflow;
384 	__u32 cqes;
385 	__u32 flags;
386 	__u32 resv1;
387 	__u64 resv2;
388 };
389 
390 /*
391  * cq_ring->flags
392  */
393 
394 /* disable eventfd notifications */
395 #define IORING_CQ_EVENTFD_DISABLED	(1U << 0)
396 
397 /*
398  * io_uring_enter(2) flags
399  */
400 #define IORING_ENTER_GETEVENTS		(1U << 0)
401 #define IORING_ENTER_SQ_WAKEUP		(1U << 1)
402 #define IORING_ENTER_SQ_WAIT		(1U << 2)
403 #define IORING_ENTER_EXT_ARG		(1U << 3)
404 #define IORING_ENTER_REGISTERED_RING	(1U << 4)
405 
406 /*
407  * Passed in for io_uring_setup(2). Copied back with updated info on success
408  */
409 struct io_uring_params {
410 	__u32 sq_entries;
411 	__u32 cq_entries;
412 	__u32 flags;
413 	__u32 sq_thread_cpu;
414 	__u32 sq_thread_idle;
415 	__u32 features;
416 	__u32 wq_fd;
417 	__u32 resv[3];
418 	struct io_sqring_offsets sq_off;
419 	struct io_cqring_offsets cq_off;
420 };
421 
422 /*
423  * io_uring_params->features flags
424  */
425 #define IORING_FEAT_SINGLE_MMAP		(1U << 0)
426 #define IORING_FEAT_NODROP		(1U << 1)
427 #define IORING_FEAT_SUBMIT_STABLE	(1U << 2)
428 #define IORING_FEAT_RW_CUR_POS		(1U << 3)
429 #define IORING_FEAT_CUR_PERSONALITY	(1U << 4)
430 #define IORING_FEAT_FAST_POLL		(1U << 5)
431 #define IORING_FEAT_POLL_32BITS 	(1U << 6)
432 #define IORING_FEAT_SQPOLL_NONFIXED	(1U << 7)
433 #define IORING_FEAT_EXT_ARG		(1U << 8)
434 #define IORING_FEAT_NATIVE_WORKERS	(1U << 9)
435 #define IORING_FEAT_RSRC_TAGS		(1U << 10)
436 #define IORING_FEAT_CQE_SKIP		(1U << 11)
437 #define IORING_FEAT_LINKED_FILE		(1U << 12)
438 
439 /*
440  * io_uring_register(2) opcodes and arguments
441  */
442 enum {
443 	IORING_REGISTER_BUFFERS			= 0,
444 	IORING_UNREGISTER_BUFFERS		= 1,
445 	IORING_REGISTER_FILES			= 2,
446 	IORING_UNREGISTER_FILES			= 3,
447 	IORING_REGISTER_EVENTFD			= 4,
448 	IORING_UNREGISTER_EVENTFD		= 5,
449 	IORING_REGISTER_FILES_UPDATE		= 6,
450 	IORING_REGISTER_EVENTFD_ASYNC		= 7,
451 	IORING_REGISTER_PROBE			= 8,
452 	IORING_REGISTER_PERSONALITY		= 9,
453 	IORING_UNREGISTER_PERSONALITY		= 10,
454 	IORING_REGISTER_RESTRICTIONS		= 11,
455 	IORING_REGISTER_ENABLE_RINGS		= 12,
456 
457 	/* extended with tagging */
458 	IORING_REGISTER_FILES2			= 13,
459 	IORING_REGISTER_FILES_UPDATE2		= 14,
460 	IORING_REGISTER_BUFFERS2		= 15,
461 	IORING_REGISTER_BUFFERS_UPDATE		= 16,
462 
463 	/* set/clear io-wq thread affinities */
464 	IORING_REGISTER_IOWQ_AFF		= 17,
465 	IORING_UNREGISTER_IOWQ_AFF		= 18,
466 
467 	/* set/get max number of io-wq workers */
468 	IORING_REGISTER_IOWQ_MAX_WORKERS	= 19,
469 
470 	/* register/unregister io_uring fd with the ring */
471 	IORING_REGISTER_RING_FDS		= 20,
472 	IORING_UNREGISTER_RING_FDS		= 21,
473 
474 	/* register ring based provide buffer group */
475 	IORING_REGISTER_PBUF_RING		= 22,
476 	IORING_UNREGISTER_PBUF_RING		= 23,
477 
478 	/* sync cancelation API */
479 	IORING_REGISTER_SYNC_CANCEL		= 24,
480 
481 	/* register a range of fixed file slots for automatic slot allocation */
482 	IORING_REGISTER_FILE_ALLOC_RANGE	= 25,
483 
484 	/* zerocopy notification API */
485 	IORING_REGISTER_NOTIFIERS		= 26,
486 	IORING_UNREGISTER_NOTIFIERS		= 27,
487 
488 	/* this goes last */
489 	IORING_REGISTER_LAST
490 };
491 
492 /* io-wq worker categories */
493 enum {
494 	IO_WQ_BOUND,
495 	IO_WQ_UNBOUND,
496 };
497 
498 /* deprecated, see struct io_uring_rsrc_update */
499 struct io_uring_files_update {
500 	__u32 offset;
501 	__u32 resv;
502 	__aligned_u64 /* __s32 * */ fds;
503 };
504 
505 /*
506  * Register a fully sparse file space, rather than pass in an array of all
507  * -1 file descriptors.
508  */
509 #define IORING_RSRC_REGISTER_SPARSE	(1U << 0)
510 
511 struct io_uring_rsrc_register {
512 	__u32 nr;
513 	__u32 flags;
514 	__u64 resv2;
515 	__aligned_u64 data;
516 	__aligned_u64 tags;
517 };
518 
519 struct io_uring_rsrc_update {
520 	__u32 offset;
521 	__u32 resv;
522 	__aligned_u64 data;
523 };
524 
525 struct io_uring_rsrc_update2 {
526 	__u32 offset;
527 	__u32 resv;
528 	__aligned_u64 data;
529 	__aligned_u64 tags;
530 	__u32 nr;
531 	__u32 resv2;
532 };
533 
534 struct io_uring_notification_slot {
535 	__u64 tag;
536 	__u64 resv[3];
537 };
538 
539 struct io_uring_notification_register {
540 	__u32 nr_slots;
541 	__u32 resv;
542 	__u64 resv2;
543 	__u64 data;
544 	__u64 resv3;
545 };
546 
547 /* Skip updating fd indexes set to this value in the fd table */
548 #define IORING_REGISTER_FILES_SKIP	(-2)
549 
550 #define IO_URING_OP_SUPPORTED	(1U << 0)
551 
552 struct io_uring_probe_op {
553 	__u8 op;
554 	__u8 resv;
555 	__u16 flags;	/* IO_URING_OP_* flags */
556 	__u32 resv2;
557 };
558 
559 struct io_uring_probe {
560 	__u8 last_op;	/* last opcode supported */
561 	__u8 ops_len;	/* length of ops[] array below */
562 	__u16 resv;
563 	__u32 resv2[3];
564 	struct io_uring_probe_op ops[];
565 };
566 
567 struct io_uring_restriction {
568 	__u16 opcode;
569 	union {
570 		__u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
571 		__u8 sqe_op;      /* IORING_RESTRICTION_SQE_OP */
572 		__u8 sqe_flags;   /* IORING_RESTRICTION_SQE_FLAGS_* */
573 	};
574 	__u8 resv;
575 	__u32 resv2[3];
576 };
577 
578 struct io_uring_buf {
579 	__u64	addr;
580 	__u32	len;
581 	__u16	bid;
582 	__u16	resv;
583 };
584 
585 struct io_uring_buf_ring {
586 	union {
587 		/*
588 		 * To avoid spilling into more pages than we need to, the
589 		 * ring tail is overlaid with the io_uring_buf->resv field.
590 		 */
591 		struct {
592 			__u64	resv1;
593 			__u32	resv2;
594 			__u16	resv3;
595 			__u16	tail;
596 		};
597 		struct io_uring_buf	bufs[0];
598 	};
599 };
600 
601 /* argument for IORING_(UN)REGISTER_PBUF_RING */
602 struct io_uring_buf_reg {
603 	__u64	ring_addr;
604 	__u32	ring_entries;
605 	__u16	bgid;
606 	__u16	pad;
607 	__u64	resv[3];
608 };
609 
610 /*
611  * io_uring_restriction->opcode values
612  */
613 enum {
614 	/* Allow an io_uring_register(2) opcode */
615 	IORING_RESTRICTION_REGISTER_OP		= 0,
616 
617 	/* Allow an sqe opcode */
618 	IORING_RESTRICTION_SQE_OP		= 1,
619 
620 	/* Allow sqe flags */
621 	IORING_RESTRICTION_SQE_FLAGS_ALLOWED	= 2,
622 
623 	/* Require sqe flags (these flags must be set on each submission) */
624 	IORING_RESTRICTION_SQE_FLAGS_REQUIRED	= 3,
625 
626 	IORING_RESTRICTION_LAST
627 };
628 
629 struct io_uring_getevents_arg {
630 	__u64	sigmask;
631 	__u32	sigmask_sz;
632 	__u32	pad;
633 	__u64	ts;
634 };
635 
636 /*
637  * Argument for IORING_REGISTER_SYNC_CANCEL
638  */
639 struct io_uring_sync_cancel_reg {
640 	__u64				addr;
641 	__s32				fd;
642 	__u32				flags;
643 	struct __kernel_timespec	timeout;
644 	__u64				pad[4];
645 };
646 
647 /*
648  * Argument for IORING_REGISTER_FILE_ALLOC_RANGE
649  * The range is specified as [off, off + len)
650  */
651 struct io_uring_file_index_range {
652 	__u32	off;
653 	__u32	len;
654 	__u64	resv;
655 };
656 
657 struct io_uring_recvmsg_out {
658 	__u32 namelen;
659 	__u32 controllen;
660 	__u32 payloadlen;
661 	__u32 flags;
662 };
663 
664 #endif
665