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 /*
14  * this file is shared with liburing and that has to autodetect
15  * if linux/time_types.h is available or not, it can
16  * define UAPI_LINUX_IO_URING_H_SKIP_LINUX_TIME_TYPES_H
17  * if linux/time_types.h is not available
18  */
19 #ifndef UAPI_LINUX_IO_URING_H_SKIP_LINUX_TIME_TYPES_H
20 #include <linux/time_types.h>
21 #endif
22 
23 #ifdef __cplusplus
24 extern "C" {
25 #endif
26 
27 /*
28  * IO submission data structure (Submission Queue Entry)
29  */
30 struct io_uring_sqe {
31 	__u8	opcode;		/* type of operation for this sqe */
32 	__u8	flags;		/* IOSQE_ flags */
33 	__u16	ioprio;		/* ioprio for the request */
34 	__s32	fd;		/* file descriptor to do IO on */
35 	union {
36 		__u64	off;	/* offset into file */
37 		__u64	addr2;
38 		struct {
39 			__u32	cmd_op;
40 			__u32	__pad1;
41 		};
42 	};
43 	union {
44 		__u64	addr;	/* pointer to buffer or iovecs */
45 		__u64	splice_off_in;
46 		struct {
47 			__u32	level;
48 			__u32	optname;
49 		};
50 	};
51 	__u32	len;		/* buffer size or number of iovecs */
52 	union {
53 		__kernel_rwf_t	rw_flags;
54 		__u32		fsync_flags;
55 		__u16		poll_events;	/* compatibility */
56 		__u32		poll32_events;	/* word-reversed for BE */
57 		__u32		sync_range_flags;
58 		__u32		msg_flags;
59 		__u32		timeout_flags;
60 		__u32		accept_flags;
61 		__u32		cancel_flags;
62 		__u32		open_flags;
63 		__u32		statx_flags;
64 		__u32		fadvise_advice;
65 		__u32		splice_flags;
66 		__u32		rename_flags;
67 		__u32		unlink_flags;
68 		__u32		hardlink_flags;
69 		__u32		xattr_flags;
70 		__u32		msg_ring_flags;
71 		__u32		uring_cmd_flags;
72 		__u32		waitid_flags;
73 		__u32		futex_flags;
74 	};
75 	__u64	user_data;	/* data to be passed back at completion time */
76 	/* pack this to avoid bogus arm OABI complaints */
77 	union {
78 		/* index into fixed buffers, if used */
79 		__u16	buf_index;
80 		/* for grouped buffer selection */
81 		__u16	buf_group;
82 	} __attribute__((packed));
83 	/* personality to use, if used */
84 	__u16	personality;
85 	union {
86 		__s32	splice_fd_in;
87 		__u32	file_index;
88 		__u32	optlen;
89 		struct {
90 			__u16	addr_len;
91 			__u16	__pad3[1];
92 		};
93 	};
94 	union {
95 		struct {
96 			__u64	addr3;
97 			__u64	__pad2[1];
98 		};
99 		__u64	optval;
100 		/*
101 		 * If the ring is initialized with IORING_SETUP_SQE128, then
102 		 * this field is used for 80 bytes of arbitrary command data
103 		 */
104 		__u8	cmd[0];
105 	};
106 };
107 
108 /*
109  * If sqe->file_index is set to this for opcodes that instantiate a new
110  * direct descriptor (like openat/openat2/accept), then io_uring will allocate
111  * an available direct descriptor instead of having the application pass one
112  * in. The picked direct descriptor will be returned in cqe->res, or -ENFILE
113  * if the space is full.
114  */
115 #define IORING_FILE_INDEX_ALLOC		(~0U)
116 
117 enum {
118 	IOSQE_FIXED_FILE_BIT,
119 	IOSQE_IO_DRAIN_BIT,
120 	IOSQE_IO_LINK_BIT,
121 	IOSQE_IO_HARDLINK_BIT,
122 	IOSQE_ASYNC_BIT,
123 	IOSQE_BUFFER_SELECT_BIT,
124 	IOSQE_CQE_SKIP_SUCCESS_BIT,
125 };
126 
127 /*
128  * sqe->flags
129  */
130 /* use fixed fileset */
131 #define IOSQE_FIXED_FILE	(1U << IOSQE_FIXED_FILE_BIT)
132 /* issue after inflight IO */
133 #define IOSQE_IO_DRAIN		(1U << IOSQE_IO_DRAIN_BIT)
134 /* links next sqe */
135 #define IOSQE_IO_LINK		(1U << IOSQE_IO_LINK_BIT)
136 /* like LINK, but stronger */
137 #define IOSQE_IO_HARDLINK	(1U << IOSQE_IO_HARDLINK_BIT)
138 /* always go async */
139 #define IOSQE_ASYNC		(1U << IOSQE_ASYNC_BIT)
140 /* select buffer from sqe->buf_group */
141 #define IOSQE_BUFFER_SELECT	(1U << IOSQE_BUFFER_SELECT_BIT)
142 /* don't post CQE if request succeeded */
143 #define IOSQE_CQE_SKIP_SUCCESS	(1U << IOSQE_CQE_SKIP_SUCCESS_BIT)
144 
145 /*
146  * io_uring_setup() flags
147  */
148 #define IORING_SETUP_IOPOLL	(1U << 0)	/* io_context is polled */
149 #define IORING_SETUP_SQPOLL	(1U << 1)	/* SQ poll thread */
150 #define IORING_SETUP_SQ_AFF	(1U << 2)	/* sq_thread_cpu is valid */
151 #define IORING_SETUP_CQSIZE	(1U << 3)	/* app defines CQ size */
152 #define IORING_SETUP_CLAMP	(1U << 4)	/* clamp SQ/CQ ring sizes */
153 #define IORING_SETUP_ATTACH_WQ	(1U << 5)	/* attach to existing wq */
154 #define IORING_SETUP_R_DISABLED	(1U << 6)	/* start with ring disabled */
155 #define IORING_SETUP_SUBMIT_ALL	(1U << 7)	/* continue submit on error */
156 /*
157  * Cooperative task running. When requests complete, they often require
158  * forcing the submitter to transition to the kernel to complete. If this
159  * flag is set, work will be done when the task transitions anyway, rather
160  * than force an inter-processor interrupt reschedule. This avoids interrupting
161  * a task running in userspace, and saves an IPI.
162  */
163 #define IORING_SETUP_COOP_TASKRUN	(1U << 8)
164 /*
165  * If COOP_TASKRUN is set, get notified if task work is available for
166  * running and a kernel transition would be needed to run it. This sets
167  * IORING_SQ_TASKRUN in the sq ring flags. Not valid with COOP_TASKRUN.
168  */
169 #define IORING_SETUP_TASKRUN_FLAG	(1U << 9)
170 #define IORING_SETUP_SQE128		(1U << 10) /* SQEs are 128 byte */
171 #define IORING_SETUP_CQE32		(1U << 11) /* CQEs are 32 byte */
172 /*
173  * Only one task is allowed to submit requests
174  */
175 #define IORING_SETUP_SINGLE_ISSUER	(1U << 12)
176 
177 /*
178  * Defer running task work to get events.
179  * Rather than running bits of task work whenever the task transitions
180  * try to do it just before it is needed.
181  */
182 #define IORING_SETUP_DEFER_TASKRUN	(1U << 13)
183 
184 /*
185  * Application provides the memory for the rings
186  */
187 #define IORING_SETUP_NO_MMAP		(1U << 14)
188 
189 /*
190  * Register the ring fd in itself for use with
191  * IORING_REGISTER_USE_REGISTERED_RING; return a registered fd index rather
192  * than an fd.
193  */
194 #define IORING_SETUP_REGISTERED_FD_ONLY	(1U << 15)
195 
196 /*
197  * Removes indirection through the SQ index array.
198  */
199 #define IORING_SETUP_NO_SQARRAY		(1U << 16)
200 
201 enum io_uring_op {
202 	IORING_OP_NOP,
203 	IORING_OP_READV,
204 	IORING_OP_WRITEV,
205 	IORING_OP_FSYNC,
206 	IORING_OP_READ_FIXED,
207 	IORING_OP_WRITE_FIXED,
208 	IORING_OP_POLL_ADD,
209 	IORING_OP_POLL_REMOVE,
210 	IORING_OP_SYNC_FILE_RANGE,
211 	IORING_OP_SENDMSG,
212 	IORING_OP_RECVMSG,
213 	IORING_OP_TIMEOUT,
214 	IORING_OP_TIMEOUT_REMOVE,
215 	IORING_OP_ACCEPT,
216 	IORING_OP_ASYNC_CANCEL,
217 	IORING_OP_LINK_TIMEOUT,
218 	IORING_OP_CONNECT,
219 	IORING_OP_FALLOCATE,
220 	IORING_OP_OPENAT,
221 	IORING_OP_CLOSE,
222 	IORING_OP_FILES_UPDATE,
223 	IORING_OP_STATX,
224 	IORING_OP_READ,
225 	IORING_OP_WRITE,
226 	IORING_OP_FADVISE,
227 	IORING_OP_MADVISE,
228 	IORING_OP_SEND,
229 	IORING_OP_RECV,
230 	IORING_OP_OPENAT2,
231 	IORING_OP_EPOLL_CTL,
232 	IORING_OP_SPLICE,
233 	IORING_OP_PROVIDE_BUFFERS,
234 	IORING_OP_REMOVE_BUFFERS,
235 	IORING_OP_TEE,
236 	IORING_OP_SHUTDOWN,
237 	IORING_OP_RENAMEAT,
238 	IORING_OP_UNLINKAT,
239 	IORING_OP_MKDIRAT,
240 	IORING_OP_SYMLINKAT,
241 	IORING_OP_LINKAT,
242 	IORING_OP_MSG_RING,
243 	IORING_OP_FSETXATTR,
244 	IORING_OP_SETXATTR,
245 	IORING_OP_FGETXATTR,
246 	IORING_OP_GETXATTR,
247 	IORING_OP_SOCKET,
248 	IORING_OP_URING_CMD,
249 	IORING_OP_SEND_ZC,
250 	IORING_OP_SENDMSG_ZC,
251 	IORING_OP_READ_MULTISHOT,
252 	IORING_OP_WAITID,
253 	IORING_OP_FUTEX_WAIT,
254 	IORING_OP_FUTEX_WAKE,
255 	IORING_OP_FUTEX_WAITV,
256 
257 	/* this goes last, obviously */
258 	IORING_OP_LAST,
259 };
260 
261 /*
262  * sqe->uring_cmd_flags		top 8bits aren't available for userspace
263  * IORING_URING_CMD_FIXED	use registered buffer; pass this flag
264  *				along with setting sqe->buf_index.
265  */
266 #define IORING_URING_CMD_FIXED	(1U << 0)
267 #define IORING_URING_CMD_MASK	IORING_URING_CMD_FIXED
268 
269 
270 /*
271  * sqe->fsync_flags
272  */
273 #define IORING_FSYNC_DATASYNC	(1U << 0)
274 
275 /*
276  * sqe->timeout_flags
277  */
278 #define IORING_TIMEOUT_ABS		(1U << 0)
279 #define IORING_TIMEOUT_UPDATE		(1U << 1)
280 #define IORING_TIMEOUT_BOOTTIME		(1U << 2)
281 #define IORING_TIMEOUT_REALTIME		(1U << 3)
282 #define IORING_LINK_TIMEOUT_UPDATE	(1U << 4)
283 #define IORING_TIMEOUT_ETIME_SUCCESS	(1U << 5)
284 #define IORING_TIMEOUT_MULTISHOT	(1U << 6)
285 #define IORING_TIMEOUT_CLOCK_MASK	(IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME)
286 #define IORING_TIMEOUT_UPDATE_MASK	(IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE)
287 /*
288  * sqe->splice_flags
289  * extends splice(2) flags
290  */
291 #define SPLICE_F_FD_IN_FIXED	(1U << 31) /* the last bit of __u32 */
292 
293 /*
294  * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the
295  * command flags for POLL_ADD are stored in sqe->len.
296  *
297  * IORING_POLL_ADD_MULTI	Multishot poll. Sets IORING_CQE_F_MORE if
298  *				the poll handler will continue to report
299  *				CQEs on behalf of the same SQE.
300  *
301  * IORING_POLL_UPDATE		Update existing poll request, matching
302  *				sqe->addr as the old user_data field.
303  *
304  * IORING_POLL_LEVEL		Level triggered poll.
305  */
306 #define IORING_POLL_ADD_MULTI	(1U << 0)
307 #define IORING_POLL_UPDATE_EVENTS	(1U << 1)
308 #define IORING_POLL_UPDATE_USER_DATA	(1U << 2)
309 #define IORING_POLL_ADD_LEVEL		(1U << 3)
310 
311 /*
312  * ASYNC_CANCEL flags.
313  *
314  * IORING_ASYNC_CANCEL_ALL	Cancel all requests that match the given key
315  * IORING_ASYNC_CANCEL_FD	Key off 'fd' for cancelation rather than the
316  *				request 'user_data'
317  * IORING_ASYNC_CANCEL_ANY	Match any request
318  * IORING_ASYNC_CANCEL_FD_FIXED	'fd' passed in is a fixed descriptor
319  * IORING_ASYNC_CANCEL_USERDATA	Match on user_data, default for no other key
320  * IORING_ASYNC_CANCEL_OP	Match request based on opcode
321  */
322 #define IORING_ASYNC_CANCEL_ALL	(1U << 0)
323 #define IORING_ASYNC_CANCEL_FD	(1U << 1)
324 #define IORING_ASYNC_CANCEL_ANY	(1U << 2)
325 #define IORING_ASYNC_CANCEL_FD_FIXED	(1U << 3)
326 #define IORING_ASYNC_CANCEL_USERDATA	(1U << 4)
327 #define IORING_ASYNC_CANCEL_OP	(1U << 5)
328 
329 /*
330  * send/sendmsg and recv/recvmsg flags (sqe->ioprio)
331  *
332  * IORING_RECVSEND_POLL_FIRST	If set, instead of first attempting to send
333  *				or receive and arm poll if that yields an
334  *				-EAGAIN result, arm poll upfront and skip
335  *				the initial transfer attempt.
336  *
337  * IORING_RECV_MULTISHOT	Multishot recv. Sets IORING_CQE_F_MORE if
338  *				the handler will continue to report
339  *				CQEs on behalf of the same SQE.
340  *
341  * IORING_RECVSEND_FIXED_BUF	Use registered buffers, the index is stored in
342  *				the buf_index field.
343  *
344  * IORING_SEND_ZC_REPORT_USAGE
345  *				If set, SEND[MSG]_ZC should report
346  *				the zerocopy usage in cqe.res
347  *				for the IORING_CQE_F_NOTIF cqe.
348  *				0 is reported if zerocopy was actually possible.
349  *				IORING_NOTIF_USAGE_ZC_COPIED if data was copied
350  *				(at least partially).
351  */
352 #define IORING_RECVSEND_POLL_FIRST	(1U << 0)
353 #define IORING_RECV_MULTISHOT		(1U << 1)
354 #define IORING_RECVSEND_FIXED_BUF	(1U << 2)
355 #define IORING_SEND_ZC_REPORT_USAGE	(1U << 3)
356 
357 /*
358  * cqe.res for IORING_CQE_F_NOTIF if
359  * IORING_SEND_ZC_REPORT_USAGE was requested
360  *
361  * It should be treated as a flag, all other
362  * bits of cqe.res should be treated as reserved!
363  */
364 #define IORING_NOTIF_USAGE_ZC_COPIED    (1U << 31)
365 
366 /*
367  * accept flags stored in sqe->ioprio
368  */
369 #define IORING_ACCEPT_MULTISHOT	(1U << 0)
370 
371 /*
372  * IORING_OP_MSG_RING command types, stored in sqe->addr
373  */
374 enum {
375 	IORING_MSG_DATA,	/* pass sqe->len as 'res' and off as user_data */
376 	IORING_MSG_SEND_FD,	/* send a registered fd to another ring */
377 };
378 
379 /*
380  * IORING_OP_MSG_RING flags (sqe->msg_ring_flags)
381  *
382  * IORING_MSG_RING_CQE_SKIP	Don't post a CQE to the target ring. Not
383  *				applicable for IORING_MSG_DATA, obviously.
384  */
385 #define IORING_MSG_RING_CQE_SKIP	(1U << 0)
386 /* Pass through the flags from sqe->file_index to cqe->flags */
387 #define IORING_MSG_RING_FLAGS_PASS	(1U << 1)
388 
389 /*
390  * IO completion data structure (Completion Queue Entry)
391  */
392 struct io_uring_cqe {
393 	__u64	user_data;	/* sqe->data submission passed back */
394 	__s32	res;		/* result code for this event */
395 	__u32	flags;
396 
397 	/*
398 	 * If the ring is initialized with IORING_SETUP_CQE32, then this field
399 	 * contains 16-bytes of padding, doubling the size of the CQE.
400 	 */
401 	__u64 big_cqe[];
402 };
403 
404 /*
405  * cqe->flags
406  *
407  * IORING_CQE_F_BUFFER	If set, the upper 16 bits are the buffer ID
408  * IORING_CQE_F_MORE	If set, parent SQE will generate more CQE entries
409  * IORING_CQE_F_SOCK_NONEMPTY	If set, more data to read after socket recv
410  * IORING_CQE_F_NOTIF	Set for notification CQEs. Can be used to distinct
411  * 			them from sends.
412  */
413 #define IORING_CQE_F_BUFFER		(1U << 0)
414 #define IORING_CQE_F_MORE		(1U << 1)
415 #define IORING_CQE_F_SOCK_NONEMPTY	(1U << 2)
416 #define IORING_CQE_F_NOTIF		(1U << 3)
417 
418 enum {
419 	IORING_CQE_BUFFER_SHIFT		= 16,
420 };
421 
422 /*
423  * Magic offsets for the application to mmap the data it needs
424  */
425 #define IORING_OFF_SQ_RING		0ULL
426 #define IORING_OFF_CQ_RING		0x8000000ULL
427 #define IORING_OFF_SQES			0x10000000ULL
428 #define IORING_OFF_PBUF_RING		0x80000000ULL
429 #define IORING_OFF_PBUF_SHIFT		16
430 #define IORING_OFF_MMAP_MASK		0xf8000000ULL
431 
432 /*
433  * Filled with the offset for mmap(2)
434  */
435 struct io_sqring_offsets {
436 	__u32 head;
437 	__u32 tail;
438 	__u32 ring_mask;
439 	__u32 ring_entries;
440 	__u32 flags;
441 	__u32 dropped;
442 	__u32 array;
443 	__u32 resv1;
444 	__u64 user_addr;
445 };
446 
447 /*
448  * sq_ring->flags
449  */
450 #define IORING_SQ_NEED_WAKEUP	(1U << 0) /* needs io_uring_enter wakeup */
451 #define IORING_SQ_CQ_OVERFLOW	(1U << 1) /* CQ ring is overflown */
452 #define IORING_SQ_TASKRUN	(1U << 2) /* task should enter the kernel */
453 
454 struct io_cqring_offsets {
455 	__u32 head;
456 	__u32 tail;
457 	__u32 ring_mask;
458 	__u32 ring_entries;
459 	__u32 overflow;
460 	__u32 cqes;
461 	__u32 flags;
462 	__u32 resv1;
463 	__u64 user_addr;
464 };
465 
466 /*
467  * cq_ring->flags
468  */
469 
470 /* disable eventfd notifications */
471 #define IORING_CQ_EVENTFD_DISABLED	(1U << 0)
472 
473 /*
474  * io_uring_enter(2) flags
475  */
476 #define IORING_ENTER_GETEVENTS		(1U << 0)
477 #define IORING_ENTER_SQ_WAKEUP		(1U << 1)
478 #define IORING_ENTER_SQ_WAIT		(1U << 2)
479 #define IORING_ENTER_EXT_ARG		(1U << 3)
480 #define IORING_ENTER_REGISTERED_RING	(1U << 4)
481 
482 /*
483  * Passed in for io_uring_setup(2). Copied back with updated info on success
484  */
485 struct io_uring_params {
486 	__u32 sq_entries;
487 	__u32 cq_entries;
488 	__u32 flags;
489 	__u32 sq_thread_cpu;
490 	__u32 sq_thread_idle;
491 	__u32 features;
492 	__u32 wq_fd;
493 	__u32 resv[3];
494 	struct io_sqring_offsets sq_off;
495 	struct io_cqring_offsets cq_off;
496 };
497 
498 /*
499  * io_uring_params->features flags
500  */
501 #define IORING_FEAT_SINGLE_MMAP		(1U << 0)
502 #define IORING_FEAT_NODROP		(1U << 1)
503 #define IORING_FEAT_SUBMIT_STABLE	(1U << 2)
504 #define IORING_FEAT_RW_CUR_POS		(1U << 3)
505 #define IORING_FEAT_CUR_PERSONALITY	(1U << 4)
506 #define IORING_FEAT_FAST_POLL		(1U << 5)
507 #define IORING_FEAT_POLL_32BITS 	(1U << 6)
508 #define IORING_FEAT_SQPOLL_NONFIXED	(1U << 7)
509 #define IORING_FEAT_EXT_ARG		(1U << 8)
510 #define IORING_FEAT_NATIVE_WORKERS	(1U << 9)
511 #define IORING_FEAT_RSRC_TAGS		(1U << 10)
512 #define IORING_FEAT_CQE_SKIP		(1U << 11)
513 #define IORING_FEAT_LINKED_FILE		(1U << 12)
514 #define IORING_FEAT_REG_REG_RING	(1U << 13)
515 
516 /*
517  * io_uring_register(2) opcodes and arguments
518  */
519 enum {
520 	IORING_REGISTER_BUFFERS			= 0,
521 	IORING_UNREGISTER_BUFFERS		= 1,
522 	IORING_REGISTER_FILES			= 2,
523 	IORING_UNREGISTER_FILES			= 3,
524 	IORING_REGISTER_EVENTFD			= 4,
525 	IORING_UNREGISTER_EVENTFD		= 5,
526 	IORING_REGISTER_FILES_UPDATE		= 6,
527 	IORING_REGISTER_EVENTFD_ASYNC		= 7,
528 	IORING_REGISTER_PROBE			= 8,
529 	IORING_REGISTER_PERSONALITY		= 9,
530 	IORING_UNREGISTER_PERSONALITY		= 10,
531 	IORING_REGISTER_RESTRICTIONS		= 11,
532 	IORING_REGISTER_ENABLE_RINGS		= 12,
533 
534 	/* extended with tagging */
535 	IORING_REGISTER_FILES2			= 13,
536 	IORING_REGISTER_FILES_UPDATE2		= 14,
537 	IORING_REGISTER_BUFFERS2		= 15,
538 	IORING_REGISTER_BUFFERS_UPDATE		= 16,
539 
540 	/* set/clear io-wq thread affinities */
541 	IORING_REGISTER_IOWQ_AFF		= 17,
542 	IORING_UNREGISTER_IOWQ_AFF		= 18,
543 
544 	/* set/get max number of io-wq workers */
545 	IORING_REGISTER_IOWQ_MAX_WORKERS	= 19,
546 
547 	/* register/unregister io_uring fd with the ring */
548 	IORING_REGISTER_RING_FDS		= 20,
549 	IORING_UNREGISTER_RING_FDS		= 21,
550 
551 	/* register ring based provide buffer group */
552 	IORING_REGISTER_PBUF_RING		= 22,
553 	IORING_UNREGISTER_PBUF_RING		= 23,
554 
555 	/* sync cancelation API */
556 	IORING_REGISTER_SYNC_CANCEL		= 24,
557 
558 	/* register a range of fixed file slots for automatic slot allocation */
559 	IORING_REGISTER_FILE_ALLOC_RANGE	= 25,
560 
561 	/* this goes last */
562 	IORING_REGISTER_LAST,
563 
564 	/* flag added to the opcode to use a registered ring fd */
565 	IORING_REGISTER_USE_REGISTERED_RING	= 1U << 31
566 };
567 
568 /* io-wq worker categories */
569 enum {
570 	IO_WQ_BOUND,
571 	IO_WQ_UNBOUND,
572 };
573 
574 /* deprecated, see struct io_uring_rsrc_update */
575 struct io_uring_files_update {
576 	__u32 offset;
577 	__u32 resv;
578 	__aligned_u64 /* __s32 * */ fds;
579 };
580 
581 /*
582  * Register a fully sparse file space, rather than pass in an array of all
583  * -1 file descriptors.
584  */
585 #define IORING_RSRC_REGISTER_SPARSE	(1U << 0)
586 
587 struct io_uring_rsrc_register {
588 	__u32 nr;
589 	__u32 flags;
590 	__u64 resv2;
591 	__aligned_u64 data;
592 	__aligned_u64 tags;
593 };
594 
595 struct io_uring_rsrc_update {
596 	__u32 offset;
597 	__u32 resv;
598 	__aligned_u64 data;
599 };
600 
601 struct io_uring_rsrc_update2 {
602 	__u32 offset;
603 	__u32 resv;
604 	__aligned_u64 data;
605 	__aligned_u64 tags;
606 	__u32 nr;
607 	__u32 resv2;
608 };
609 
610 /* Skip updating fd indexes set to this value in the fd table */
611 #define IORING_REGISTER_FILES_SKIP	(-2)
612 
613 #define IO_URING_OP_SUPPORTED	(1U << 0)
614 
615 struct io_uring_probe_op {
616 	__u8 op;
617 	__u8 resv;
618 	__u16 flags;	/* IO_URING_OP_* flags */
619 	__u32 resv2;
620 };
621 
622 struct io_uring_probe {
623 	__u8 last_op;	/* last opcode supported */
624 	__u8 ops_len;	/* length of ops[] array below */
625 	__u16 resv;
626 	__u32 resv2[3];
627 	struct io_uring_probe_op ops[];
628 };
629 
630 struct io_uring_restriction {
631 	__u16 opcode;
632 	union {
633 		__u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
634 		__u8 sqe_op;      /* IORING_RESTRICTION_SQE_OP */
635 		__u8 sqe_flags;   /* IORING_RESTRICTION_SQE_FLAGS_* */
636 	};
637 	__u8 resv;
638 	__u32 resv2[3];
639 };
640 
641 struct io_uring_buf {
642 	__u64	addr;
643 	__u32	len;
644 	__u16	bid;
645 	__u16	resv;
646 };
647 
648 struct io_uring_buf_ring {
649 	union {
650 		/*
651 		 * To avoid spilling into more pages than we need to, the
652 		 * ring tail is overlaid with the io_uring_buf->resv field.
653 		 */
654 		struct {
655 			__u64	resv1;
656 			__u32	resv2;
657 			__u16	resv3;
658 			__u16	tail;
659 		};
660 		__DECLARE_FLEX_ARRAY(struct io_uring_buf, bufs);
661 	};
662 };
663 
664 /*
665  * Flags for IORING_REGISTER_PBUF_RING.
666  *
667  * IOU_PBUF_RING_MMAP:	If set, kernel will allocate the memory for the ring.
668  *			The application must not set a ring_addr in struct
669  *			io_uring_buf_reg, instead it must subsequently call
670  *			mmap(2) with the offset set as:
671  *			IORING_OFF_PBUF_RING | (bgid << IORING_OFF_PBUF_SHIFT)
672  *			to get a virtual mapping for the ring.
673  */
674 enum {
675 	IOU_PBUF_RING_MMAP	= 1,
676 };
677 
678 /* argument for IORING_(UN)REGISTER_PBUF_RING */
679 struct io_uring_buf_reg {
680 	__u64	ring_addr;
681 	__u32	ring_entries;
682 	__u16	bgid;
683 	__u16	flags;
684 	__u64	resv[3];
685 };
686 
687 /*
688  * io_uring_restriction->opcode values
689  */
690 enum {
691 	/* Allow an io_uring_register(2) opcode */
692 	IORING_RESTRICTION_REGISTER_OP		= 0,
693 
694 	/* Allow an sqe opcode */
695 	IORING_RESTRICTION_SQE_OP		= 1,
696 
697 	/* Allow sqe flags */
698 	IORING_RESTRICTION_SQE_FLAGS_ALLOWED	= 2,
699 
700 	/* Require sqe flags (these flags must be set on each submission) */
701 	IORING_RESTRICTION_SQE_FLAGS_REQUIRED	= 3,
702 
703 	IORING_RESTRICTION_LAST
704 };
705 
706 struct io_uring_getevents_arg {
707 	__u64	sigmask;
708 	__u32	sigmask_sz;
709 	__u32	pad;
710 	__u64	ts;
711 };
712 
713 /*
714  * Argument for IORING_REGISTER_SYNC_CANCEL
715  */
716 struct io_uring_sync_cancel_reg {
717 	__u64				addr;
718 	__s32				fd;
719 	__u32				flags;
720 	struct __kernel_timespec	timeout;
721 	__u8				opcode;
722 	__u8				pad[7];
723 	__u64				pad2[3];
724 };
725 
726 /*
727  * Argument for IORING_REGISTER_FILE_ALLOC_RANGE
728  * The range is specified as [off, off + len)
729  */
730 struct io_uring_file_index_range {
731 	__u32	off;
732 	__u32	len;
733 	__u64	resv;
734 };
735 
736 struct io_uring_recvmsg_out {
737 	__u32 namelen;
738 	__u32 controllen;
739 	__u32 payloadlen;
740 	__u32 flags;
741 };
742 
743 /*
744  * Argument for IORING_OP_URING_CMD when file is a socket
745  */
746 enum {
747 	SOCKET_URING_OP_SIOCINQ		= 0,
748 	SOCKET_URING_OP_SIOCOUTQ,
749 	SOCKET_URING_OP_GETSOCKOPT,
750 	SOCKET_URING_OP_SETSOCKOPT,
751 };
752 
753 #ifdef __cplusplus
754 }
755 #endif
756 
757 #endif
758