xref: /linux-6.15/include/uapi/linux/io_uring.h (revision dfbbfbf1)
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 		__u32		install_fd_flags;
75 		__u32		nop_flags;
76 	};
77 	__u64	user_data;	/* data to be passed back at completion time */
78 	/* pack this to avoid bogus arm OABI complaints */
79 	union {
80 		/* index into fixed buffers, if used */
81 		__u16	buf_index;
82 		/* for grouped buffer selection */
83 		__u16	buf_group;
84 	} __attribute__((packed));
85 	/* personality to use, if used */
86 	__u16	personality;
87 	union {
88 		__s32	splice_fd_in;
89 		__u32	file_index;
90 		__u32	optlen;
91 		struct {
92 			__u16	addr_len;
93 			__u16	__pad3[1];
94 		};
95 	};
96 	union {
97 		struct {
98 			__u64	addr3;
99 			__u64	__pad2[1];
100 		};
101 		__u64	optval;
102 		/*
103 		 * If the ring is initialized with IORING_SETUP_SQE128, then
104 		 * this field is used for 80 bytes of arbitrary command data
105 		 */
106 		__u8	cmd[0];
107 	};
108 };
109 
110 /*
111  * If sqe->file_index is set to this for opcodes that instantiate a new
112  * direct descriptor (like openat/openat2/accept), then io_uring will allocate
113  * an available direct descriptor instead of having the application pass one
114  * in. The picked direct descriptor will be returned in cqe->res, or -ENFILE
115  * if the space is full.
116  */
117 #define IORING_FILE_INDEX_ALLOC		(~0U)
118 
119 enum io_uring_sqe_flags_bit {
120 	IOSQE_FIXED_FILE_BIT,
121 	IOSQE_IO_DRAIN_BIT,
122 	IOSQE_IO_LINK_BIT,
123 	IOSQE_IO_HARDLINK_BIT,
124 	IOSQE_ASYNC_BIT,
125 	IOSQE_BUFFER_SELECT_BIT,
126 	IOSQE_CQE_SKIP_SUCCESS_BIT,
127 };
128 
129 /*
130  * sqe->flags
131  */
132 /* use fixed fileset */
133 #define IOSQE_FIXED_FILE	(1U << IOSQE_FIXED_FILE_BIT)
134 /* issue after inflight IO */
135 #define IOSQE_IO_DRAIN		(1U << IOSQE_IO_DRAIN_BIT)
136 /* links next sqe */
137 #define IOSQE_IO_LINK		(1U << IOSQE_IO_LINK_BIT)
138 /* like LINK, but stronger */
139 #define IOSQE_IO_HARDLINK	(1U << IOSQE_IO_HARDLINK_BIT)
140 /* always go async */
141 #define IOSQE_ASYNC		(1U << IOSQE_ASYNC_BIT)
142 /* select buffer from sqe->buf_group */
143 #define IOSQE_BUFFER_SELECT	(1U << IOSQE_BUFFER_SELECT_BIT)
144 /* don't post CQE if request succeeded */
145 #define IOSQE_CQE_SKIP_SUCCESS	(1U << IOSQE_CQE_SKIP_SUCCESS_BIT)
146 
147 /*
148  * io_uring_setup() flags
149  */
150 #define IORING_SETUP_IOPOLL	(1U << 0)	/* io_context is polled */
151 #define IORING_SETUP_SQPOLL	(1U << 1)	/* SQ poll thread */
152 #define IORING_SETUP_SQ_AFF	(1U << 2)	/* sq_thread_cpu is valid */
153 #define IORING_SETUP_CQSIZE	(1U << 3)	/* app defines CQ size */
154 #define IORING_SETUP_CLAMP	(1U << 4)	/* clamp SQ/CQ ring sizes */
155 #define IORING_SETUP_ATTACH_WQ	(1U << 5)	/* attach to existing wq */
156 #define IORING_SETUP_R_DISABLED	(1U << 6)	/* start with ring disabled */
157 #define IORING_SETUP_SUBMIT_ALL	(1U << 7)	/* continue submit on error */
158 /*
159  * Cooperative task running. When requests complete, they often require
160  * forcing the submitter to transition to the kernel to complete. If this
161  * flag is set, work will be done when the task transitions anyway, rather
162  * than force an inter-processor interrupt reschedule. This avoids interrupting
163  * a task running in userspace, and saves an IPI.
164  */
165 #define IORING_SETUP_COOP_TASKRUN	(1U << 8)
166 /*
167  * If COOP_TASKRUN is set, get notified if task work is available for
168  * running and a kernel transition would be needed to run it. This sets
169  * IORING_SQ_TASKRUN in the sq ring flags. Not valid with COOP_TASKRUN.
170  */
171 #define IORING_SETUP_TASKRUN_FLAG	(1U << 9)
172 #define IORING_SETUP_SQE128		(1U << 10) /* SQEs are 128 byte */
173 #define IORING_SETUP_CQE32		(1U << 11) /* CQEs are 32 byte */
174 /*
175  * Only one task is allowed to submit requests
176  */
177 #define IORING_SETUP_SINGLE_ISSUER	(1U << 12)
178 
179 /*
180  * Defer running task work to get events.
181  * Rather than running bits of task work whenever the task transitions
182  * try to do it just before it is needed.
183  */
184 #define IORING_SETUP_DEFER_TASKRUN	(1U << 13)
185 
186 /*
187  * Application provides the memory for the rings
188  */
189 #define IORING_SETUP_NO_MMAP		(1U << 14)
190 
191 /*
192  * Register the ring fd in itself for use with
193  * IORING_REGISTER_USE_REGISTERED_RING; return a registered fd index rather
194  * than an fd.
195  */
196 #define IORING_SETUP_REGISTERED_FD_ONLY	(1U << 15)
197 
198 /*
199  * Removes indirection through the SQ index array.
200  */
201 #define IORING_SETUP_NO_SQARRAY		(1U << 16)
202 
203 /* Use hybrid poll in iopoll process */
204 #define IORING_SETUP_HYBRID_IOPOLL	(1U << 17)
205 
206 enum io_uring_op {
207 	IORING_OP_NOP,
208 	IORING_OP_READV,
209 	IORING_OP_WRITEV,
210 	IORING_OP_FSYNC,
211 	IORING_OP_READ_FIXED,
212 	IORING_OP_WRITE_FIXED,
213 	IORING_OP_POLL_ADD,
214 	IORING_OP_POLL_REMOVE,
215 	IORING_OP_SYNC_FILE_RANGE,
216 	IORING_OP_SENDMSG,
217 	IORING_OP_RECVMSG,
218 	IORING_OP_TIMEOUT,
219 	IORING_OP_TIMEOUT_REMOVE,
220 	IORING_OP_ACCEPT,
221 	IORING_OP_ASYNC_CANCEL,
222 	IORING_OP_LINK_TIMEOUT,
223 	IORING_OP_CONNECT,
224 	IORING_OP_FALLOCATE,
225 	IORING_OP_OPENAT,
226 	IORING_OP_CLOSE,
227 	IORING_OP_FILES_UPDATE,
228 	IORING_OP_STATX,
229 	IORING_OP_READ,
230 	IORING_OP_WRITE,
231 	IORING_OP_FADVISE,
232 	IORING_OP_MADVISE,
233 	IORING_OP_SEND,
234 	IORING_OP_RECV,
235 	IORING_OP_OPENAT2,
236 	IORING_OP_EPOLL_CTL,
237 	IORING_OP_SPLICE,
238 	IORING_OP_PROVIDE_BUFFERS,
239 	IORING_OP_REMOVE_BUFFERS,
240 	IORING_OP_TEE,
241 	IORING_OP_SHUTDOWN,
242 	IORING_OP_RENAMEAT,
243 	IORING_OP_UNLINKAT,
244 	IORING_OP_MKDIRAT,
245 	IORING_OP_SYMLINKAT,
246 	IORING_OP_LINKAT,
247 	IORING_OP_MSG_RING,
248 	IORING_OP_FSETXATTR,
249 	IORING_OP_SETXATTR,
250 	IORING_OP_FGETXATTR,
251 	IORING_OP_GETXATTR,
252 	IORING_OP_SOCKET,
253 	IORING_OP_URING_CMD,
254 	IORING_OP_SEND_ZC,
255 	IORING_OP_SENDMSG_ZC,
256 	IORING_OP_READ_MULTISHOT,
257 	IORING_OP_WAITID,
258 	IORING_OP_FUTEX_WAIT,
259 	IORING_OP_FUTEX_WAKE,
260 	IORING_OP_FUTEX_WAITV,
261 	IORING_OP_FIXED_FD_INSTALL,
262 	IORING_OP_FTRUNCATE,
263 	IORING_OP_BIND,
264 	IORING_OP_LISTEN,
265 
266 	/* this goes last, obviously */
267 	IORING_OP_LAST,
268 };
269 
270 /*
271  * sqe->uring_cmd_flags		top 8bits aren't available for userspace
272  * IORING_URING_CMD_FIXED	use registered buffer; pass this flag
273  *				along with setting sqe->buf_index.
274  */
275 #define IORING_URING_CMD_FIXED	(1U << 0)
276 #define IORING_URING_CMD_MASK	IORING_URING_CMD_FIXED
277 
278 
279 /*
280  * sqe->fsync_flags
281  */
282 #define IORING_FSYNC_DATASYNC	(1U << 0)
283 
284 /*
285  * sqe->timeout_flags
286  */
287 #define IORING_TIMEOUT_ABS		(1U << 0)
288 #define IORING_TIMEOUT_UPDATE		(1U << 1)
289 #define IORING_TIMEOUT_BOOTTIME		(1U << 2)
290 #define IORING_TIMEOUT_REALTIME		(1U << 3)
291 #define IORING_LINK_TIMEOUT_UPDATE	(1U << 4)
292 #define IORING_TIMEOUT_ETIME_SUCCESS	(1U << 5)
293 #define IORING_TIMEOUT_MULTISHOT	(1U << 6)
294 #define IORING_TIMEOUT_CLOCK_MASK	(IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME)
295 #define IORING_TIMEOUT_UPDATE_MASK	(IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE)
296 /*
297  * sqe->splice_flags
298  * extends splice(2) flags
299  */
300 #define SPLICE_F_FD_IN_FIXED	(1U << 31) /* the last bit of __u32 */
301 
302 /*
303  * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the
304  * command flags for POLL_ADD are stored in sqe->len.
305  *
306  * IORING_POLL_ADD_MULTI	Multishot poll. Sets IORING_CQE_F_MORE if
307  *				the poll handler will continue to report
308  *				CQEs on behalf of the same SQE.
309  *
310  * IORING_POLL_UPDATE		Update existing poll request, matching
311  *				sqe->addr as the old user_data field.
312  *
313  * IORING_POLL_LEVEL		Level triggered poll.
314  */
315 #define IORING_POLL_ADD_MULTI	(1U << 0)
316 #define IORING_POLL_UPDATE_EVENTS	(1U << 1)
317 #define IORING_POLL_UPDATE_USER_DATA	(1U << 2)
318 #define IORING_POLL_ADD_LEVEL		(1U << 3)
319 
320 /*
321  * ASYNC_CANCEL flags.
322  *
323  * IORING_ASYNC_CANCEL_ALL	Cancel all requests that match the given key
324  * IORING_ASYNC_CANCEL_FD	Key off 'fd' for cancelation rather than the
325  *				request 'user_data'
326  * IORING_ASYNC_CANCEL_ANY	Match any request
327  * IORING_ASYNC_CANCEL_FD_FIXED	'fd' passed in is a fixed descriptor
328  * IORING_ASYNC_CANCEL_USERDATA	Match on user_data, default for no other key
329  * IORING_ASYNC_CANCEL_OP	Match request based on opcode
330  */
331 #define IORING_ASYNC_CANCEL_ALL	(1U << 0)
332 #define IORING_ASYNC_CANCEL_FD	(1U << 1)
333 #define IORING_ASYNC_CANCEL_ANY	(1U << 2)
334 #define IORING_ASYNC_CANCEL_FD_FIXED	(1U << 3)
335 #define IORING_ASYNC_CANCEL_USERDATA	(1U << 4)
336 #define IORING_ASYNC_CANCEL_OP	(1U << 5)
337 
338 /*
339  * send/sendmsg and recv/recvmsg flags (sqe->ioprio)
340  *
341  * IORING_RECVSEND_POLL_FIRST	If set, instead of first attempting to send
342  *				or receive and arm poll if that yields an
343  *				-EAGAIN result, arm poll upfront and skip
344  *				the initial transfer attempt.
345  *
346  * IORING_RECV_MULTISHOT	Multishot recv. Sets IORING_CQE_F_MORE if
347  *				the handler will continue to report
348  *				CQEs on behalf of the same SQE.
349  *
350  * IORING_RECVSEND_FIXED_BUF	Use registered buffers, the index is stored in
351  *				the buf_index field.
352  *
353  * IORING_SEND_ZC_REPORT_USAGE
354  *				If set, SEND[MSG]_ZC should report
355  *				the zerocopy usage in cqe.res
356  *				for the IORING_CQE_F_NOTIF cqe.
357  *				0 is reported if zerocopy was actually possible.
358  *				IORING_NOTIF_USAGE_ZC_COPIED if data was copied
359  *				(at least partially).
360  *
361  * IORING_RECVSEND_BUNDLE	Used with IOSQE_BUFFER_SELECT. If set, send or
362  *				recv will grab as many buffers from the buffer
363  *				group ID given and send them all. The completion
364  *				result 	will be the number of buffers send, with
365  *				the starting buffer ID in cqe->flags as per
366  *				usual for provided buffer usage. The buffers
367  *				will be	contigious from the starting buffer ID.
368  */
369 #define IORING_RECVSEND_POLL_FIRST	(1U << 0)
370 #define IORING_RECV_MULTISHOT		(1U << 1)
371 #define IORING_RECVSEND_FIXED_BUF	(1U << 2)
372 #define IORING_SEND_ZC_REPORT_USAGE	(1U << 3)
373 #define IORING_RECVSEND_BUNDLE		(1U << 4)
374 
375 /*
376  * cqe.res for IORING_CQE_F_NOTIF if
377  * IORING_SEND_ZC_REPORT_USAGE was requested
378  *
379  * It should be treated as a flag, all other
380  * bits of cqe.res should be treated as reserved!
381  */
382 #define IORING_NOTIF_USAGE_ZC_COPIED    (1U << 31)
383 
384 /*
385  * accept flags stored in sqe->ioprio
386  */
387 #define IORING_ACCEPT_MULTISHOT	(1U << 0)
388 #define IORING_ACCEPT_DONTWAIT	(1U << 1)
389 #define IORING_ACCEPT_POLL_FIRST	(1U << 2)
390 
391 /*
392  * IORING_OP_MSG_RING command types, stored in sqe->addr
393  */
394 enum io_uring_msg_ring_flags {
395 	IORING_MSG_DATA,	/* pass sqe->len as 'res' and off as user_data */
396 	IORING_MSG_SEND_FD,	/* send a registered fd to another ring */
397 };
398 
399 /*
400  * IORING_OP_MSG_RING flags (sqe->msg_ring_flags)
401  *
402  * IORING_MSG_RING_CQE_SKIP	Don't post a CQE to the target ring. Not
403  *				applicable for IORING_MSG_DATA, obviously.
404  */
405 #define IORING_MSG_RING_CQE_SKIP	(1U << 0)
406 /* Pass through the flags from sqe->file_index to cqe->flags */
407 #define IORING_MSG_RING_FLAGS_PASS	(1U << 1)
408 
409 /*
410  * IORING_OP_FIXED_FD_INSTALL flags (sqe->install_fd_flags)
411  *
412  * IORING_FIXED_FD_NO_CLOEXEC	Don't mark the fd as O_CLOEXEC
413  */
414 #define IORING_FIXED_FD_NO_CLOEXEC	(1U << 0)
415 
416 /*
417  * IORING_OP_NOP flags (sqe->nop_flags)
418  *
419  * IORING_NOP_INJECT_RESULT	Inject result from sqe->result
420  */
421 #define IORING_NOP_INJECT_RESULT	(1U << 0)
422 #define IORING_NOP_FILE			(1U << 1)
423 #define IORING_NOP_FIXED_FILE		(1U << 2)
424 #define IORING_NOP_FIXED_BUFFER		(1U << 3)
425 
426 /*
427  * IO completion data structure (Completion Queue Entry)
428  */
429 struct io_uring_cqe {
430 	__u64	user_data;	/* sqe->user_data value passed back */
431 	__s32	res;		/* result code for this event */
432 	__u32	flags;
433 
434 	/*
435 	 * If the ring is initialized with IORING_SETUP_CQE32, then this field
436 	 * contains 16-bytes of padding, doubling the size of the CQE.
437 	 */
438 	__u64 big_cqe[];
439 };
440 
441 /*
442  * cqe->flags
443  *
444  * IORING_CQE_F_BUFFER	If set, the upper 16 bits are the buffer ID
445  * IORING_CQE_F_MORE	If set, parent SQE will generate more CQE entries
446  * IORING_CQE_F_SOCK_NONEMPTY	If set, more data to read after socket recv
447  * IORING_CQE_F_NOTIF	Set for notification CQEs. Can be used to distinct
448  * 			them from sends.
449  * IORING_CQE_F_BUF_MORE If set, the buffer ID set in the completion will get
450  *			more completions. In other words, the buffer is being
451  *			partially consumed, and will be used by the kernel for
452  *			more completions. This is only set for buffers used via
453  *			the incremental buffer consumption, as provided by
454  *			a ring buffer setup with IOU_PBUF_RING_INC. For any
455  *			other provided buffer type, all completions with a
456  *			buffer passed back is automatically returned to the
457  *			application.
458  */
459 #define IORING_CQE_F_BUFFER		(1U << 0)
460 #define IORING_CQE_F_MORE		(1U << 1)
461 #define IORING_CQE_F_SOCK_NONEMPTY	(1U << 2)
462 #define IORING_CQE_F_NOTIF		(1U << 3)
463 #define IORING_CQE_F_BUF_MORE		(1U << 4)
464 
465 #define IORING_CQE_BUFFER_SHIFT		16
466 
467 /*
468  * Magic offsets for the application to mmap the data it needs
469  */
470 #define IORING_OFF_SQ_RING		0ULL
471 #define IORING_OFF_CQ_RING		0x8000000ULL
472 #define IORING_OFF_SQES			0x10000000ULL
473 #define IORING_OFF_PBUF_RING		0x80000000ULL
474 #define IORING_OFF_PBUF_SHIFT		16
475 #define IORING_OFF_MMAP_MASK		0xf8000000ULL
476 
477 /*
478  * Filled with the offset for mmap(2)
479  */
480 struct io_sqring_offsets {
481 	__u32 head;
482 	__u32 tail;
483 	__u32 ring_mask;
484 	__u32 ring_entries;
485 	__u32 flags;
486 	__u32 dropped;
487 	__u32 array;
488 	__u32 resv1;
489 	__u64 user_addr;
490 };
491 
492 /*
493  * sq_ring->flags
494  */
495 #define IORING_SQ_NEED_WAKEUP	(1U << 0) /* needs io_uring_enter wakeup */
496 #define IORING_SQ_CQ_OVERFLOW	(1U << 1) /* CQ ring is overflown */
497 #define IORING_SQ_TASKRUN	(1U << 2) /* task should enter the kernel */
498 
499 struct io_cqring_offsets {
500 	__u32 head;
501 	__u32 tail;
502 	__u32 ring_mask;
503 	__u32 ring_entries;
504 	__u32 overflow;
505 	__u32 cqes;
506 	__u32 flags;
507 	__u32 resv1;
508 	__u64 user_addr;
509 };
510 
511 /*
512  * cq_ring->flags
513  */
514 
515 /* disable eventfd notifications */
516 #define IORING_CQ_EVENTFD_DISABLED	(1U << 0)
517 
518 /*
519  * io_uring_enter(2) flags
520  */
521 #define IORING_ENTER_GETEVENTS		(1U << 0)
522 #define IORING_ENTER_SQ_WAKEUP		(1U << 1)
523 #define IORING_ENTER_SQ_WAIT		(1U << 2)
524 #define IORING_ENTER_EXT_ARG		(1U << 3)
525 #define IORING_ENTER_REGISTERED_RING	(1U << 4)
526 #define IORING_ENTER_ABS_TIMER		(1U << 5)
527 #define IORING_ENTER_EXT_ARG_REG	(1U << 6)
528 
529 /*
530  * Passed in for io_uring_setup(2). Copied back with updated info on success
531  */
532 struct io_uring_params {
533 	__u32 sq_entries;
534 	__u32 cq_entries;
535 	__u32 flags;
536 	__u32 sq_thread_cpu;
537 	__u32 sq_thread_idle;
538 	__u32 features;
539 	__u32 wq_fd;
540 	__u32 resv[3];
541 	struct io_sqring_offsets sq_off;
542 	struct io_cqring_offsets cq_off;
543 };
544 
545 /*
546  * io_uring_params->features flags
547  */
548 #define IORING_FEAT_SINGLE_MMAP		(1U << 0)
549 #define IORING_FEAT_NODROP		(1U << 1)
550 #define IORING_FEAT_SUBMIT_STABLE	(1U << 2)
551 #define IORING_FEAT_RW_CUR_POS		(1U << 3)
552 #define IORING_FEAT_CUR_PERSONALITY	(1U << 4)
553 #define IORING_FEAT_FAST_POLL		(1U << 5)
554 #define IORING_FEAT_POLL_32BITS 	(1U << 6)
555 #define IORING_FEAT_SQPOLL_NONFIXED	(1U << 7)
556 #define IORING_FEAT_EXT_ARG		(1U << 8)
557 #define IORING_FEAT_NATIVE_WORKERS	(1U << 9)
558 #define IORING_FEAT_RSRC_TAGS		(1U << 10)
559 #define IORING_FEAT_CQE_SKIP		(1U << 11)
560 #define IORING_FEAT_LINKED_FILE		(1U << 12)
561 #define IORING_FEAT_REG_REG_RING	(1U << 13)
562 #define IORING_FEAT_RECVSEND_BUNDLE	(1U << 14)
563 #define IORING_FEAT_MIN_TIMEOUT		(1U << 15)
564 
565 /*
566  * io_uring_register(2) opcodes and arguments
567  */
568 enum io_uring_register_op {
569 	IORING_REGISTER_BUFFERS			= 0,
570 	IORING_UNREGISTER_BUFFERS		= 1,
571 	IORING_REGISTER_FILES			= 2,
572 	IORING_UNREGISTER_FILES			= 3,
573 	IORING_REGISTER_EVENTFD			= 4,
574 	IORING_UNREGISTER_EVENTFD		= 5,
575 	IORING_REGISTER_FILES_UPDATE		= 6,
576 	IORING_REGISTER_EVENTFD_ASYNC		= 7,
577 	IORING_REGISTER_PROBE			= 8,
578 	IORING_REGISTER_PERSONALITY		= 9,
579 	IORING_UNREGISTER_PERSONALITY		= 10,
580 	IORING_REGISTER_RESTRICTIONS		= 11,
581 	IORING_REGISTER_ENABLE_RINGS		= 12,
582 
583 	/* extended with tagging */
584 	IORING_REGISTER_FILES2			= 13,
585 	IORING_REGISTER_FILES_UPDATE2		= 14,
586 	IORING_REGISTER_BUFFERS2		= 15,
587 	IORING_REGISTER_BUFFERS_UPDATE		= 16,
588 
589 	/* set/clear io-wq thread affinities */
590 	IORING_REGISTER_IOWQ_AFF		= 17,
591 	IORING_UNREGISTER_IOWQ_AFF		= 18,
592 
593 	/* set/get max number of io-wq workers */
594 	IORING_REGISTER_IOWQ_MAX_WORKERS	= 19,
595 
596 	/* register/unregister io_uring fd with the ring */
597 	IORING_REGISTER_RING_FDS		= 20,
598 	IORING_UNREGISTER_RING_FDS		= 21,
599 
600 	/* register ring based provide buffer group */
601 	IORING_REGISTER_PBUF_RING		= 22,
602 	IORING_UNREGISTER_PBUF_RING		= 23,
603 
604 	/* sync cancelation API */
605 	IORING_REGISTER_SYNC_CANCEL		= 24,
606 
607 	/* register a range of fixed file slots for automatic slot allocation */
608 	IORING_REGISTER_FILE_ALLOC_RANGE	= 25,
609 
610 	/* return status information for a buffer group */
611 	IORING_REGISTER_PBUF_STATUS		= 26,
612 
613 	/* set/clear busy poll settings */
614 	IORING_REGISTER_NAPI			= 27,
615 	IORING_UNREGISTER_NAPI			= 28,
616 
617 	IORING_REGISTER_CLOCK			= 29,
618 
619 	/* clone registered buffers from source ring to current ring */
620 	IORING_REGISTER_CLONE_BUFFERS		= 30,
621 
622 	/* send MSG_RING without having a ring */
623 	IORING_REGISTER_SEND_MSG_RING		= 31,
624 
625 	/* 32 reserved for zc rx */
626 
627 	/* resize CQ ring */
628 	IORING_REGISTER_RESIZE_RINGS		= 33,
629 
630 	/* this goes last */
631 	IORING_REGISTER_LAST,
632 
633 	/* flag added to the opcode to use a registered ring fd */
634 	IORING_REGISTER_USE_REGISTERED_RING	= 1U << 31
635 };
636 
637 /* io-wq worker categories */
638 enum io_wq_type {
639 	IO_WQ_BOUND,
640 	IO_WQ_UNBOUND,
641 };
642 
643 /* deprecated, see struct io_uring_rsrc_update */
644 struct io_uring_files_update {
645 	__u32 offset;
646 	__u32 resv;
647 	__aligned_u64 /* __s32 * */ fds;
648 };
649 
650 enum {
651 	/* initialise with user provided memory pointed by user_addr */
652 	IORING_MEM_REGION_TYPE_USER		= 1,
653 };
654 
655 struct io_uring_region_desc {
656 	__u64 user_addr;
657 	__u64 size;
658 	__u32 flags;
659 	__u32 id;
660 	__u64 mmap_offset;
661 	__u64 __resv[4];
662 };
663 
664 /*
665  * Register a fully sparse file space, rather than pass in an array of all
666  * -1 file descriptors.
667  */
668 #define IORING_RSRC_REGISTER_SPARSE	(1U << 0)
669 
670 struct io_uring_rsrc_register {
671 	__u32 nr;
672 	__u32 flags;
673 	__u64 resv2;
674 	__aligned_u64 data;
675 	__aligned_u64 tags;
676 };
677 
678 struct io_uring_rsrc_update {
679 	__u32 offset;
680 	__u32 resv;
681 	__aligned_u64 data;
682 };
683 
684 struct io_uring_rsrc_update2 {
685 	__u32 offset;
686 	__u32 resv;
687 	__aligned_u64 data;
688 	__aligned_u64 tags;
689 	__u32 nr;
690 	__u32 resv2;
691 };
692 
693 /* Skip updating fd indexes set to this value in the fd table */
694 #define IORING_REGISTER_FILES_SKIP	(-2)
695 
696 #define IO_URING_OP_SUPPORTED	(1U << 0)
697 
698 struct io_uring_probe_op {
699 	__u8 op;
700 	__u8 resv;
701 	__u16 flags;	/* IO_URING_OP_* flags */
702 	__u32 resv2;
703 };
704 
705 struct io_uring_probe {
706 	__u8 last_op;	/* last opcode supported */
707 	__u8 ops_len;	/* length of ops[] array below */
708 	__u16 resv;
709 	__u32 resv2[3];
710 	struct io_uring_probe_op ops[];
711 };
712 
713 struct io_uring_restriction {
714 	__u16 opcode;
715 	union {
716 		__u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
717 		__u8 sqe_op;      /* IORING_RESTRICTION_SQE_OP */
718 		__u8 sqe_flags;   /* IORING_RESTRICTION_SQE_FLAGS_* */
719 	};
720 	__u8 resv;
721 	__u32 resv2[3];
722 };
723 
724 struct io_uring_clock_register {
725 	__u32	clockid;
726 	__u32	__resv[3];
727 };
728 
729 enum {
730 	IORING_REGISTER_SRC_REGISTERED	= (1U << 0),
731 	IORING_REGISTER_DST_REPLACE	= (1U << 1),
732 };
733 
734 struct io_uring_clone_buffers {
735 	__u32	src_fd;
736 	__u32	flags;
737 	__u32	src_off;
738 	__u32	dst_off;
739 	__u32	nr;
740 	__u32	pad[3];
741 };
742 
743 struct io_uring_buf {
744 	__u64	addr;
745 	__u32	len;
746 	__u16	bid;
747 	__u16	resv;
748 };
749 
750 struct io_uring_buf_ring {
751 	union {
752 		/*
753 		 * To avoid spilling into more pages than we need to, the
754 		 * ring tail is overlaid with the io_uring_buf->resv field.
755 		 */
756 		struct {
757 			__u64	resv1;
758 			__u32	resv2;
759 			__u16	resv3;
760 			__u16	tail;
761 		};
762 		__DECLARE_FLEX_ARRAY(struct io_uring_buf, bufs);
763 	};
764 };
765 
766 /*
767  * Flags for IORING_REGISTER_PBUF_RING.
768  *
769  * IOU_PBUF_RING_MMAP:	If set, kernel will allocate the memory for the ring.
770  *			The application must not set a ring_addr in struct
771  *			io_uring_buf_reg, instead it must subsequently call
772  *			mmap(2) with the offset set as:
773  *			IORING_OFF_PBUF_RING | (bgid << IORING_OFF_PBUF_SHIFT)
774  *			to get a virtual mapping for the ring.
775  * IOU_PBUF_RING_INC:	If set, buffers consumed from this buffer ring can be
776  *			consumed incrementally. Normally one (or more) buffers
777  *			are fully consumed. With incremental consumptions, it's
778  *			feasible to register big ranges of buffers, and each
779  *			use of it will consume only as much as it needs. This
780  *			requires that both the kernel and application keep
781  *			track of where the current read/recv index is at.
782  */
783 enum io_uring_register_pbuf_ring_flags {
784 	IOU_PBUF_RING_MMAP	= 1,
785 	IOU_PBUF_RING_INC	= 2,
786 };
787 
788 /* argument for IORING_(UN)REGISTER_PBUF_RING */
789 struct io_uring_buf_reg {
790 	__u64	ring_addr;
791 	__u32	ring_entries;
792 	__u16	bgid;
793 	__u16	flags;
794 	__u64	resv[3];
795 };
796 
797 /* argument for IORING_REGISTER_PBUF_STATUS */
798 struct io_uring_buf_status {
799 	__u32	buf_group;	/* input */
800 	__u32	head;		/* output */
801 	__u32	resv[8];
802 };
803 
804 enum io_uring_napi_op {
805 	/* register/ungister backward compatible opcode */
806 	IO_URING_NAPI_REGISTER_OP = 0,
807 
808 	/* opcodes to update napi_list when static tracking is used */
809 	IO_URING_NAPI_STATIC_ADD_ID = 1,
810 	IO_URING_NAPI_STATIC_DEL_ID = 2
811 };
812 
813 enum io_uring_napi_tracking_strategy {
814 	/* value must be 0 for backward compatibility */
815 	IO_URING_NAPI_TRACKING_DYNAMIC = 0,
816 	IO_URING_NAPI_TRACKING_STATIC = 1,
817 	IO_URING_NAPI_TRACKING_INACTIVE = 255
818 };
819 
820 /* argument for IORING_(UN)REGISTER_NAPI */
821 struct io_uring_napi {
822 	__u32	busy_poll_to;
823 	__u8	prefer_busy_poll;
824 
825 	/* a io_uring_napi_op value */
826 	__u8	opcode;
827 	__u8	pad[2];
828 
829 	/*
830 	 * for IO_URING_NAPI_REGISTER_OP, it is a
831 	 * io_uring_napi_tracking_strategy value.
832 	 *
833 	 * for IO_URING_NAPI_STATIC_ADD_ID/IO_URING_NAPI_STATIC_DEL_ID
834 	 * it is the napi id to add/del from napi_list.
835 	 */
836 	__u32	op_param;
837 	__u32	resv;
838 };
839 
840 /*
841  * io_uring_restriction->opcode values
842  */
843 enum io_uring_register_restriction_op {
844 	/* Allow an io_uring_register(2) opcode */
845 	IORING_RESTRICTION_REGISTER_OP		= 0,
846 
847 	/* Allow an sqe opcode */
848 	IORING_RESTRICTION_SQE_OP		= 1,
849 
850 	/* Allow sqe flags */
851 	IORING_RESTRICTION_SQE_FLAGS_ALLOWED	= 2,
852 
853 	/* Require sqe flags (these flags must be set on each submission) */
854 	IORING_RESTRICTION_SQE_FLAGS_REQUIRED	= 3,
855 
856 	IORING_RESTRICTION_LAST
857 };
858 
859 enum {
860 	IORING_REG_WAIT_TS		= (1U << 0),
861 };
862 
863 /*
864  * Argument for IORING_REGISTER_CQWAIT_REG, registering a region of
865  * struct io_uring_reg_wait that can be indexed when io_uring_enter(2) is
866  * called rather than pass in a wait argument structure separately.
867  */
868 struct io_uring_cqwait_reg_arg {
869 	__u32		flags;
870 	__u32		struct_size;
871 	__u32		nr_entries;
872 	__u32		pad;
873 	__u64		user_addr;
874 	__u64		pad2[3];
875 };
876 
877 /*
878  * Argument for io_uring_enter(2) with
879  * IORING_GETEVENTS | IORING_ENTER_EXT_ARG_REG set, where the actual argument
880  * is an index into a previously registered fixed wait region described by
881  * the below structure.
882  */
883 struct io_uring_reg_wait {
884 	struct __kernel_timespec	ts;
885 	__u32				min_wait_usec;
886 	__u32				flags;
887 	__u64				sigmask;
888 	__u32				sigmask_sz;
889 	__u32				pad[3];
890 	__u64				pad2[2];
891 };
892 
893 /*
894  * Argument for io_uring_enter(2) with IORING_GETEVENTS | IORING_ENTER_EXT_ARG
895  */
896 struct io_uring_getevents_arg {
897 	__u64	sigmask;
898 	__u32	sigmask_sz;
899 	__u32	min_wait_usec;
900 	__u64	ts;
901 };
902 
903 /*
904  * Argument for IORING_REGISTER_SYNC_CANCEL
905  */
906 struct io_uring_sync_cancel_reg {
907 	__u64				addr;
908 	__s32				fd;
909 	__u32				flags;
910 	struct __kernel_timespec	timeout;
911 	__u8				opcode;
912 	__u8				pad[7];
913 	__u64				pad2[3];
914 };
915 
916 /*
917  * Argument for IORING_REGISTER_FILE_ALLOC_RANGE
918  * The range is specified as [off, off + len)
919  */
920 struct io_uring_file_index_range {
921 	__u32	off;
922 	__u32	len;
923 	__u64	resv;
924 };
925 
926 struct io_uring_recvmsg_out {
927 	__u32 namelen;
928 	__u32 controllen;
929 	__u32 payloadlen;
930 	__u32 flags;
931 };
932 
933 /*
934  * Argument for IORING_OP_URING_CMD when file is a socket
935  */
936 enum io_uring_socket_op {
937 	SOCKET_URING_OP_SIOCINQ		= 0,
938 	SOCKET_URING_OP_SIOCOUTQ,
939 	SOCKET_URING_OP_GETSOCKOPT,
940 	SOCKET_URING_OP_SETSOCKOPT,
941 };
942 
943 #ifdef __cplusplus
944 }
945 #endif
946 
947 #endif
948