xref: /linux/include/uapi/linux/io_uring.h (revision 041c16acbafbdd8c089cc077c78e060322dde18c)
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 		__u32		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 		__u32		pipe_flags;
77 	};
78 	__u64	user_data;	/* data to be passed back at completion time */
79 	/* pack this to avoid bogus arm OABI complaints */
80 	union {
81 		/* index into fixed buffers, if used */
82 		__u16	buf_index;
83 		/* for grouped buffer selection */
84 		__u16	buf_group;
85 	} __attribute__((packed));
86 	/* personality to use, if used */
87 	__u16	personality;
88 	union {
89 		__s32	splice_fd_in;
90 		__u32	file_index;
91 		__u32	zcrx_ifq_idx;
92 		__u32	optlen;
93 		struct {
94 			__u16	addr_len;
95 			__u16	__pad3[1];
96 		};
97 		struct {
98 			__u8	write_stream;
99 			__u8	__pad4[3];
100 		};
101 	};
102 	union {
103 		struct {
104 			__u64	addr3;
105 			__u64	__pad2[1];
106 		};
107 		struct {
108 			__u64	attr_ptr; /* pointer to attribute information */
109 			__u64	attr_type_mask; /* bit mask of attributes */
110 		};
111 		__u64	optval;
112 		/*
113 		 * If the ring is initialized with IORING_SETUP_SQE128, then
114 		 * this field is used for 80 bytes of arbitrary command data
115 		 */
116 		__u8	cmd[0];
117 	};
118 };
119 
120 /* sqe->attr_type_mask flags */
121 #define IORING_RW_ATTR_FLAG_PI	(1U << 0)
122 /* PI attribute information */
123 struct io_uring_attr_pi {
124 		__u16	flags;
125 		__u16	app_tag;
126 		__u32	len;
127 		__u64	addr;
128 		__u64	seed;
129 		__u64	rsvd;
130 };
131 
132 /*
133  * If sqe->file_index is set to this for opcodes that instantiate a new
134  * direct descriptor (like openat/openat2/accept), then io_uring will allocate
135  * an available direct descriptor instead of having the application pass one
136  * in. The picked direct descriptor will be returned in cqe->res, or -ENFILE
137  * if the space is full.
138  */
139 #define IORING_FILE_INDEX_ALLOC		(~0U)
140 
141 enum io_uring_sqe_flags_bit {
142 	IOSQE_FIXED_FILE_BIT,
143 	IOSQE_IO_DRAIN_BIT,
144 	IOSQE_IO_LINK_BIT,
145 	IOSQE_IO_HARDLINK_BIT,
146 	IOSQE_ASYNC_BIT,
147 	IOSQE_BUFFER_SELECT_BIT,
148 	IOSQE_CQE_SKIP_SUCCESS_BIT,
149 };
150 
151 /*
152  * sqe->flags
153  */
154 /* use fixed fileset */
155 #define IOSQE_FIXED_FILE	(1U << IOSQE_FIXED_FILE_BIT)
156 /* issue after inflight IO */
157 #define IOSQE_IO_DRAIN		(1U << IOSQE_IO_DRAIN_BIT)
158 /* links next sqe */
159 #define IOSQE_IO_LINK		(1U << IOSQE_IO_LINK_BIT)
160 /* like LINK, but stronger */
161 #define IOSQE_IO_HARDLINK	(1U << IOSQE_IO_HARDLINK_BIT)
162 /* always go async */
163 #define IOSQE_ASYNC		(1U << IOSQE_ASYNC_BIT)
164 /* select buffer from sqe->buf_group */
165 #define IOSQE_BUFFER_SELECT	(1U << IOSQE_BUFFER_SELECT_BIT)
166 /* don't post CQE if request succeeded */
167 #define IOSQE_CQE_SKIP_SUCCESS	(1U << IOSQE_CQE_SKIP_SUCCESS_BIT)
168 
169 /*
170  * io_uring_setup() flags
171  */
172 #define IORING_SETUP_IOPOLL	(1U << 0)	/* io_context is polled */
173 #define IORING_SETUP_SQPOLL	(1U << 1)	/* SQ poll thread */
174 #define IORING_SETUP_SQ_AFF	(1U << 2)	/* sq_thread_cpu is valid */
175 #define IORING_SETUP_CQSIZE	(1U << 3)	/* app defines CQ size */
176 #define IORING_SETUP_CLAMP	(1U << 4)	/* clamp SQ/CQ ring sizes */
177 #define IORING_SETUP_ATTACH_WQ	(1U << 5)	/* attach to existing wq */
178 #define IORING_SETUP_R_DISABLED	(1U << 6)	/* start with ring disabled */
179 #define IORING_SETUP_SUBMIT_ALL	(1U << 7)	/* continue submit on error */
180 /*
181  * Cooperative task running. When requests complete, they often require
182  * forcing the submitter to transition to the kernel to complete. If this
183  * flag is set, work will be done when the task transitions anyway, rather
184  * than force an inter-processor interrupt reschedule. This avoids interrupting
185  * a task running in userspace, and saves an IPI.
186  */
187 #define IORING_SETUP_COOP_TASKRUN	(1U << 8)
188 /*
189  * If COOP_TASKRUN is set, get notified if task work is available for
190  * running and a kernel transition would be needed to run it. This sets
191  * IORING_SQ_TASKRUN in the sq ring flags. Not valid with COOP_TASKRUN.
192  */
193 #define IORING_SETUP_TASKRUN_FLAG	(1U << 9)
194 #define IORING_SETUP_SQE128		(1U << 10) /* SQEs are 128 byte */
195 #define IORING_SETUP_CQE32		(1U << 11) /* CQEs are 32 byte */
196 /*
197  * Only one task is allowed to submit requests
198  */
199 #define IORING_SETUP_SINGLE_ISSUER	(1U << 12)
200 
201 /*
202  * Defer running task work to get events.
203  * Rather than running bits of task work whenever the task transitions
204  * try to do it just before it is needed.
205  */
206 #define IORING_SETUP_DEFER_TASKRUN	(1U << 13)
207 
208 /*
209  * Application provides the memory for the rings
210  */
211 #define IORING_SETUP_NO_MMAP		(1U << 14)
212 
213 /*
214  * Register the ring fd in itself for use with
215  * IORING_REGISTER_USE_REGISTERED_RING; return a registered fd index rather
216  * than an fd.
217  */
218 #define IORING_SETUP_REGISTERED_FD_ONLY	(1U << 15)
219 
220 /*
221  * Removes indirection through the SQ index array.
222  */
223 #define IORING_SETUP_NO_SQARRAY		(1U << 16)
224 
225 /* Use hybrid poll in iopoll process */
226 #define IORING_SETUP_HYBRID_IOPOLL	(1U << 17)
227 
228 /*
229  * Allow both 16b and 32b CQEs. If a 32b CQE is posted, it will have
230  * IORING_CQE_F_32 set in cqe->flags.
231  */
232 #define IORING_SETUP_CQE_MIXED		(1U << 18)
233 
234 /*
235  * Allow both 64b and 128b SQEs. If a 128b SQE is posted, it will have
236  * a 128b opcode.
237  */
238 #define IORING_SETUP_SQE_MIXED		(1U << 19)
239 
240 /*
241  * When set, io_uring ignores SQ head and tail and fetches SQEs to submit
242  * starting from index 0 instead from the index stored in the head pointer.
243  * IOW, the user should place all SQE at the beginning of the SQ memory
244  * before issuing a submission syscall.
245  *
246  * It requires IORING_SETUP_NO_SQARRAY and is incompatible with
247  * IORING_SETUP_SQPOLL. The user must also never change the SQ head and tail
248  * values and keep it set to 0. Any other value is undefined behaviour.
249  */
250 #define IORING_SETUP_SQ_REWIND		(1U << 20)
251 
252 enum io_uring_op {
253 	IORING_OP_NOP,
254 	IORING_OP_READV,
255 	IORING_OP_WRITEV,
256 	IORING_OP_FSYNC,
257 	IORING_OP_READ_FIXED,
258 	IORING_OP_WRITE_FIXED,
259 	IORING_OP_POLL_ADD,
260 	IORING_OP_POLL_REMOVE,
261 	IORING_OP_SYNC_FILE_RANGE,
262 	IORING_OP_SENDMSG,
263 	IORING_OP_RECVMSG,
264 	IORING_OP_TIMEOUT,
265 	IORING_OP_TIMEOUT_REMOVE,
266 	IORING_OP_ACCEPT,
267 	IORING_OP_ASYNC_CANCEL,
268 	IORING_OP_LINK_TIMEOUT,
269 	IORING_OP_CONNECT,
270 	IORING_OP_FALLOCATE,
271 	IORING_OP_OPENAT,
272 	IORING_OP_CLOSE,
273 	IORING_OP_FILES_UPDATE,
274 	IORING_OP_STATX,
275 	IORING_OP_READ,
276 	IORING_OP_WRITE,
277 	IORING_OP_FADVISE,
278 	IORING_OP_MADVISE,
279 	IORING_OP_SEND,
280 	IORING_OP_RECV,
281 	IORING_OP_OPENAT2,
282 	IORING_OP_EPOLL_CTL,
283 	IORING_OP_SPLICE,
284 	IORING_OP_PROVIDE_BUFFERS,
285 	IORING_OP_REMOVE_BUFFERS,
286 	IORING_OP_TEE,
287 	IORING_OP_SHUTDOWN,
288 	IORING_OP_RENAMEAT,
289 	IORING_OP_UNLINKAT,
290 	IORING_OP_MKDIRAT,
291 	IORING_OP_SYMLINKAT,
292 	IORING_OP_LINKAT,
293 	IORING_OP_MSG_RING,
294 	IORING_OP_FSETXATTR,
295 	IORING_OP_SETXATTR,
296 	IORING_OP_FGETXATTR,
297 	IORING_OP_GETXATTR,
298 	IORING_OP_SOCKET,
299 	IORING_OP_URING_CMD,
300 	IORING_OP_SEND_ZC,
301 	IORING_OP_SENDMSG_ZC,
302 	IORING_OP_READ_MULTISHOT,
303 	IORING_OP_WAITID,
304 	IORING_OP_FUTEX_WAIT,
305 	IORING_OP_FUTEX_WAKE,
306 	IORING_OP_FUTEX_WAITV,
307 	IORING_OP_FIXED_FD_INSTALL,
308 	IORING_OP_FTRUNCATE,
309 	IORING_OP_BIND,
310 	IORING_OP_LISTEN,
311 	IORING_OP_RECV_ZC,
312 	IORING_OP_EPOLL_WAIT,
313 	IORING_OP_READV_FIXED,
314 	IORING_OP_WRITEV_FIXED,
315 	IORING_OP_PIPE,
316 	IORING_OP_NOP128,
317 	IORING_OP_URING_CMD128,
318 
319 	/* this goes last, obviously */
320 	IORING_OP_LAST,
321 };
322 
323 /*
324  * sqe->uring_cmd_flags		top 8bits aren't available for userspace
325  * IORING_URING_CMD_FIXED	use registered buffer; pass this flag
326  *				along with setting sqe->buf_index.
327  * IORING_URING_CMD_MULTISHOT	must be used with buffer select, like other
328  *				multishot commands. Not compatible with
329  *				IORING_URING_CMD_FIXED, for now.
330  */
331 #define IORING_URING_CMD_FIXED	(1U << 0)
332 #define IORING_URING_CMD_MULTISHOT	(1U << 1)
333 #define IORING_URING_CMD_MASK	(IORING_URING_CMD_FIXED | IORING_URING_CMD_MULTISHOT)
334 
335 
336 /*
337  * sqe->fsync_flags
338  */
339 #define IORING_FSYNC_DATASYNC	(1U << 0)
340 
341 /*
342  * sqe->timeout_flags
343  */
344 #define IORING_TIMEOUT_ABS		(1U << 0)
345 #define IORING_TIMEOUT_UPDATE		(1U << 1)
346 #define IORING_TIMEOUT_BOOTTIME		(1U << 2)
347 #define IORING_TIMEOUT_REALTIME		(1U << 3)
348 #define IORING_LINK_TIMEOUT_UPDATE	(1U << 4)
349 #define IORING_TIMEOUT_ETIME_SUCCESS	(1U << 5)
350 #define IORING_TIMEOUT_MULTISHOT	(1U << 6)
351 #define IORING_TIMEOUT_CLOCK_MASK	(IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME)
352 #define IORING_TIMEOUT_UPDATE_MASK	(IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE)
353 /*
354  * sqe->splice_flags
355  * extends splice(2) flags
356  */
357 #define SPLICE_F_FD_IN_FIXED	(1U << 31) /* the last bit of __u32 */
358 
359 /*
360  * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the
361  * command flags for POLL_ADD are stored in sqe->len.
362  *
363  * IORING_POLL_ADD_MULTI	Multishot poll. Sets IORING_CQE_F_MORE if
364  *				the poll handler will continue to report
365  *				CQEs on behalf of the same SQE.
366  *
367  * IORING_POLL_UPDATE		Update existing poll request, matching
368  *				sqe->addr as the old user_data field.
369  *
370  * IORING_POLL_LEVEL		Level triggered poll.
371  */
372 #define IORING_POLL_ADD_MULTI	(1U << 0)
373 #define IORING_POLL_UPDATE_EVENTS	(1U << 1)
374 #define IORING_POLL_UPDATE_USER_DATA	(1U << 2)
375 #define IORING_POLL_ADD_LEVEL		(1U << 3)
376 
377 /*
378  * ASYNC_CANCEL flags.
379  *
380  * IORING_ASYNC_CANCEL_ALL	Cancel all requests that match the given key
381  * IORING_ASYNC_CANCEL_FD	Key off 'fd' for cancelation rather than the
382  *				request 'user_data'
383  * IORING_ASYNC_CANCEL_ANY	Match any request
384  * IORING_ASYNC_CANCEL_FD_FIXED	'fd' passed in is a fixed descriptor
385  * IORING_ASYNC_CANCEL_USERDATA	Match on user_data, default for no other key
386  * IORING_ASYNC_CANCEL_OP	Match request based on opcode
387  */
388 #define IORING_ASYNC_CANCEL_ALL	(1U << 0)
389 #define IORING_ASYNC_CANCEL_FD	(1U << 1)
390 #define IORING_ASYNC_CANCEL_ANY	(1U << 2)
391 #define IORING_ASYNC_CANCEL_FD_FIXED	(1U << 3)
392 #define IORING_ASYNC_CANCEL_USERDATA	(1U << 4)
393 #define IORING_ASYNC_CANCEL_OP	(1U << 5)
394 
395 /*
396  * send/sendmsg and recv/recvmsg flags (sqe->ioprio)
397  *
398  * IORING_RECVSEND_POLL_FIRST	If set, instead of first attempting to send
399  *				or receive and arm poll if that yields an
400  *				-EAGAIN result, arm poll upfront and skip
401  *				the initial transfer attempt.
402  *
403  * IORING_RECV_MULTISHOT	Multishot recv. Sets IORING_CQE_F_MORE if
404  *				the handler will continue to report
405  *				CQEs on behalf of the same SQE.
406  *
407  * IORING_RECVSEND_FIXED_BUF	Use registered buffers, the index is stored in
408  *				the buf_index field.
409  *
410  * IORING_SEND_ZC_REPORT_USAGE
411  *				If set, SEND[MSG]_ZC should report
412  *				the zerocopy usage in cqe.res
413  *				for the IORING_CQE_F_NOTIF cqe.
414  *				0 is reported if zerocopy was actually possible.
415  *				IORING_NOTIF_USAGE_ZC_COPIED if data was copied
416  *				(at least partially).
417  *
418  * IORING_RECVSEND_BUNDLE	Used with IOSQE_BUFFER_SELECT. If set, send or
419  *				recv will grab as many buffers from the buffer
420  *				group ID given and send them all. The completion
421  *				result 	will be the number of buffers send, with
422  *				the starting buffer ID in cqe->flags as per
423  *				usual for provided buffer usage. The buffers
424  *				will be	contiguous from the starting buffer ID.
425  *
426  * IORING_SEND_VECTORIZED	If set, SEND[_ZC] will take a pointer to a io_vec
427  *				to allow vectorized send operations.
428  */
429 #define IORING_RECVSEND_POLL_FIRST	(1U << 0)
430 #define IORING_RECV_MULTISHOT		(1U << 1)
431 #define IORING_RECVSEND_FIXED_BUF	(1U << 2)
432 #define IORING_SEND_ZC_REPORT_USAGE	(1U << 3)
433 #define IORING_RECVSEND_BUNDLE		(1U << 4)
434 #define IORING_SEND_VECTORIZED		(1U << 5)
435 
436 /*
437  * cqe.res for IORING_CQE_F_NOTIF if
438  * IORING_SEND_ZC_REPORT_USAGE was requested
439  *
440  * It should be treated as a flag, all other
441  * bits of cqe.res should be treated as reserved!
442  */
443 #define IORING_NOTIF_USAGE_ZC_COPIED    (1U << 31)
444 
445 /*
446  * accept flags stored in sqe->ioprio
447  */
448 #define IORING_ACCEPT_MULTISHOT	(1U << 0)
449 #define IORING_ACCEPT_DONTWAIT	(1U << 1)
450 #define IORING_ACCEPT_POLL_FIRST	(1U << 2)
451 
452 /*
453  * IORING_OP_MSG_RING command types, stored in sqe->addr
454  */
455 enum io_uring_msg_ring_flags {
456 	IORING_MSG_DATA,	/* pass sqe->len as 'res' and off as user_data */
457 	IORING_MSG_SEND_FD,	/* send a registered fd to another ring */
458 };
459 
460 /*
461  * IORING_OP_MSG_RING flags (sqe->msg_ring_flags)
462  *
463  * IORING_MSG_RING_CQE_SKIP	Don't post a CQE to the target ring. Not
464  *				applicable for IORING_MSG_DATA, obviously.
465  */
466 #define IORING_MSG_RING_CQE_SKIP	(1U << 0)
467 /* Pass through the flags from sqe->file_index to cqe->flags */
468 #define IORING_MSG_RING_FLAGS_PASS	(1U << 1)
469 
470 /*
471  * IORING_OP_FIXED_FD_INSTALL flags (sqe->install_fd_flags)
472  *
473  * IORING_FIXED_FD_NO_CLOEXEC	Don't mark the fd as O_CLOEXEC
474  */
475 #define IORING_FIXED_FD_NO_CLOEXEC	(1U << 0)
476 
477 /*
478  * IORING_OP_NOP flags (sqe->nop_flags)
479  *
480  * IORING_NOP_INJECT_RESULT	Inject result from sqe->result
481  */
482 #define IORING_NOP_INJECT_RESULT	(1U << 0)
483 #define IORING_NOP_FILE			(1U << 1)
484 #define IORING_NOP_FIXED_FILE		(1U << 2)
485 #define IORING_NOP_FIXED_BUFFER		(1U << 3)
486 #define IORING_NOP_TW			(1U << 4)
487 #define IORING_NOP_CQE32		(1U << 5)
488 
489 /*
490  * IO completion data structure (Completion Queue Entry)
491  */
492 struct io_uring_cqe {
493 	__u64	user_data;	/* sqe->user_data value passed back */
494 	__s32	res;		/* result code for this event */
495 	__u32	flags;
496 
497 	/*
498 	 * If the ring is initialized with IORING_SETUP_CQE32, then this field
499 	 * contains 16-bytes of padding, doubling the size of the CQE.
500 	 */
501 	__u64 big_cqe[];
502 };
503 
504 /*
505  * cqe->flags
506  *
507  * IORING_CQE_F_BUFFER	If set, the upper 16 bits are the buffer ID
508  * IORING_CQE_F_MORE	If set, parent SQE will generate more CQE entries
509  * IORING_CQE_F_SOCK_NONEMPTY	If set, more data to read after socket recv
510  * IORING_CQE_F_NOTIF	Set for notification CQEs. Can be used to distinct
511  * 			them from sends.
512  * IORING_CQE_F_BUF_MORE If set, the buffer ID set in the completion will get
513  *			more completions. In other words, the buffer is being
514  *			partially consumed, and will be used by the kernel for
515  *			more completions. This is only set for buffers used via
516  *			the incremental buffer consumption, as provided by
517  *			a ring buffer setup with IOU_PBUF_RING_INC. For any
518  *			other provided buffer type, all completions with a
519  *			buffer passed back is automatically returned to the
520  *			application.
521  * IORING_CQE_F_SKIP	If set, then the application/liburing must ignore this
522  *			CQE. It's only purpose is to fill a gap in the ring,
523  *			if a large CQE is attempted posted when the ring has
524  *			just a single small CQE worth of space left before
525  *			wrapping.
526  * IORING_CQE_F_32	If set, this is a 32b/big-cqe posting. Use with rings
527  *			setup in a mixed CQE mode, where both 16b and 32b
528  *			CQEs may be posted to the CQ ring.
529  */
530 #define IORING_CQE_F_BUFFER		(1U << 0)
531 #define IORING_CQE_F_MORE		(1U << 1)
532 #define IORING_CQE_F_SOCK_NONEMPTY	(1U << 2)
533 #define IORING_CQE_F_NOTIF		(1U << 3)
534 #define IORING_CQE_F_BUF_MORE		(1U << 4)
535 #define IORING_CQE_F_SKIP		(1U << 5)
536 #define IORING_CQE_F_32			(1U << 15)
537 
538 #define IORING_CQE_BUFFER_SHIFT		16
539 
540 /*
541  * Magic offsets for the application to mmap the data it needs
542  */
543 #define IORING_OFF_SQ_RING		0ULL
544 #define IORING_OFF_CQ_RING		0x8000000ULL
545 #define IORING_OFF_SQES			0x10000000ULL
546 #define IORING_OFF_PBUF_RING		0x80000000ULL
547 #define IORING_OFF_PBUF_SHIFT		16
548 #define IORING_OFF_MMAP_MASK		0xf8000000ULL
549 
550 /*
551  * Filled with the offset for mmap(2)
552  */
553 struct io_sqring_offsets {
554 	__u32 head;
555 	__u32 tail;
556 	__u32 ring_mask;
557 	__u32 ring_entries;
558 	__u32 flags;
559 	__u32 dropped;
560 	__u32 array;
561 	__u32 resv1;
562 	__u64 user_addr;
563 };
564 
565 /*
566  * sq_ring->flags
567  */
568 #define IORING_SQ_NEED_WAKEUP	(1U << 0) /* needs io_uring_enter wakeup */
569 #define IORING_SQ_CQ_OVERFLOW	(1U << 1) /* CQ ring is overflown */
570 #define IORING_SQ_TASKRUN	(1U << 2) /* task should enter the kernel */
571 
572 struct io_cqring_offsets {
573 	__u32 head;
574 	__u32 tail;
575 	__u32 ring_mask;
576 	__u32 ring_entries;
577 	__u32 overflow;
578 	__u32 cqes;
579 	__u32 flags;
580 	__u32 resv1;
581 	__u64 user_addr;
582 };
583 
584 /*
585  * cq_ring->flags
586  */
587 
588 /* disable eventfd notifications */
589 #define IORING_CQ_EVENTFD_DISABLED	(1U << 0)
590 
591 /*
592  * io_uring_enter(2) flags
593  */
594 #define IORING_ENTER_GETEVENTS		(1U << 0)
595 #define IORING_ENTER_SQ_WAKEUP		(1U << 1)
596 #define IORING_ENTER_SQ_WAIT		(1U << 2)
597 #define IORING_ENTER_EXT_ARG		(1U << 3)
598 #define IORING_ENTER_REGISTERED_RING	(1U << 4)
599 #define IORING_ENTER_ABS_TIMER		(1U << 5)
600 #define IORING_ENTER_EXT_ARG_REG	(1U << 6)
601 #define IORING_ENTER_NO_IOWAIT		(1U << 7)
602 
603 /*
604  * Passed in for io_uring_setup(2). Copied back with updated info on success
605  */
606 struct io_uring_params {
607 	__u32 sq_entries;
608 	__u32 cq_entries;
609 	__u32 flags;
610 	__u32 sq_thread_cpu;
611 	__u32 sq_thread_idle;
612 	__u32 features;
613 	__u32 wq_fd;
614 	__u32 resv[3];
615 	struct io_sqring_offsets sq_off;
616 	struct io_cqring_offsets cq_off;
617 };
618 
619 /*
620  * io_uring_params->features flags
621  */
622 #define IORING_FEAT_SINGLE_MMAP		(1U << 0)
623 #define IORING_FEAT_NODROP		(1U << 1)
624 #define IORING_FEAT_SUBMIT_STABLE	(1U << 2)
625 #define IORING_FEAT_RW_CUR_POS		(1U << 3)
626 #define IORING_FEAT_CUR_PERSONALITY	(1U << 4)
627 #define IORING_FEAT_FAST_POLL		(1U << 5)
628 #define IORING_FEAT_POLL_32BITS 	(1U << 6)
629 #define IORING_FEAT_SQPOLL_NONFIXED	(1U << 7)
630 #define IORING_FEAT_EXT_ARG		(1U << 8)
631 #define IORING_FEAT_NATIVE_WORKERS	(1U << 9)
632 #define IORING_FEAT_RSRC_TAGS		(1U << 10)
633 #define IORING_FEAT_CQE_SKIP		(1U << 11)
634 #define IORING_FEAT_LINKED_FILE		(1U << 12)
635 #define IORING_FEAT_REG_REG_RING	(1U << 13)
636 #define IORING_FEAT_RECVSEND_BUNDLE	(1U << 14)
637 #define IORING_FEAT_MIN_TIMEOUT		(1U << 15)
638 #define IORING_FEAT_RW_ATTR		(1U << 16)
639 #define IORING_FEAT_NO_IOWAIT		(1U << 17)
640 
641 /*
642  * io_uring_register(2) opcodes and arguments
643  */
644 enum io_uring_register_op {
645 	IORING_REGISTER_BUFFERS			= 0,
646 	IORING_UNREGISTER_BUFFERS		= 1,
647 	IORING_REGISTER_FILES			= 2,
648 	IORING_UNREGISTER_FILES			= 3,
649 	IORING_REGISTER_EVENTFD			= 4,
650 	IORING_UNREGISTER_EVENTFD		= 5,
651 	IORING_REGISTER_FILES_UPDATE		= 6,
652 	IORING_REGISTER_EVENTFD_ASYNC		= 7,
653 	IORING_REGISTER_PROBE			= 8,
654 	IORING_REGISTER_PERSONALITY		= 9,
655 	IORING_UNREGISTER_PERSONALITY		= 10,
656 	IORING_REGISTER_RESTRICTIONS		= 11,
657 	IORING_REGISTER_ENABLE_RINGS		= 12,
658 
659 	/* extended with tagging */
660 	IORING_REGISTER_FILES2			= 13,
661 	IORING_REGISTER_FILES_UPDATE2		= 14,
662 	IORING_REGISTER_BUFFERS2		= 15,
663 	IORING_REGISTER_BUFFERS_UPDATE		= 16,
664 
665 	/* set/clear io-wq thread affinities */
666 	IORING_REGISTER_IOWQ_AFF		= 17,
667 	IORING_UNREGISTER_IOWQ_AFF		= 18,
668 
669 	/* set/get max number of io-wq workers */
670 	IORING_REGISTER_IOWQ_MAX_WORKERS	= 19,
671 
672 	/* register/unregister io_uring fd with the ring */
673 	IORING_REGISTER_RING_FDS		= 20,
674 	IORING_UNREGISTER_RING_FDS		= 21,
675 
676 	/* register ring based provide buffer group */
677 	IORING_REGISTER_PBUF_RING		= 22,
678 	IORING_UNREGISTER_PBUF_RING		= 23,
679 
680 	/* sync cancelation API */
681 	IORING_REGISTER_SYNC_CANCEL		= 24,
682 
683 	/* register a range of fixed file slots for automatic slot allocation */
684 	IORING_REGISTER_FILE_ALLOC_RANGE	= 25,
685 
686 	/* return status information for a buffer group */
687 	IORING_REGISTER_PBUF_STATUS		= 26,
688 
689 	/* set/clear busy poll settings */
690 	IORING_REGISTER_NAPI			= 27,
691 	IORING_UNREGISTER_NAPI			= 28,
692 
693 	IORING_REGISTER_CLOCK			= 29,
694 
695 	/* clone registered buffers from source ring to current ring */
696 	IORING_REGISTER_CLONE_BUFFERS		= 30,
697 
698 	/* send MSG_RING without having a ring */
699 	IORING_REGISTER_SEND_MSG_RING		= 31,
700 
701 	/* register a netdev hw rx queue for zerocopy */
702 	IORING_REGISTER_ZCRX_IFQ		= 32,
703 
704 	/* resize CQ ring */
705 	IORING_REGISTER_RESIZE_RINGS		= 33,
706 
707 	IORING_REGISTER_MEM_REGION		= 34,
708 
709 	/* query various aspects of io_uring, see linux/io_uring/query.h */
710 	IORING_REGISTER_QUERY			= 35,
711 
712 	/* auxiliary zcrx configuration, see enum zcrx_ctrl_op */
713 	IORING_REGISTER_ZCRX_CTRL		= 36,
714 
715 	/* register bpf filtering programs */
716 	IORING_REGISTER_BPF_FILTER		= 37,
717 
718 	/* this goes last */
719 	IORING_REGISTER_LAST,
720 
721 	/* flag added to the opcode to use a registered ring fd */
722 	IORING_REGISTER_USE_REGISTERED_RING	= 1U << 31
723 };
724 
725 /* io-wq worker categories */
726 enum io_wq_type {
727 	IO_WQ_BOUND,
728 	IO_WQ_UNBOUND,
729 };
730 
731 /* deprecated, see struct io_uring_rsrc_update */
732 struct io_uring_files_update {
733 	__u32 offset;
734 	__u32 resv;
735 	__aligned_u64 /* __s32 * */ fds;
736 };
737 
738 enum {
739 	/* initialise with user provided memory pointed by user_addr */
740 	IORING_MEM_REGION_TYPE_USER		= 1,
741 };
742 
743 struct io_uring_region_desc {
744 	__u64 user_addr;
745 	__u64 size;
746 	__u32 flags;
747 	__u32 id;
748 	__u64 mmap_offset;
749 	__u64 __resv[4];
750 };
751 
752 enum {
753 	/* expose the region as registered wait arguments */
754 	IORING_MEM_REGION_REG_WAIT_ARG		= 1,
755 };
756 
757 struct io_uring_mem_region_reg {
758 	__u64 region_uptr; /* struct io_uring_region_desc * */
759 	__u64 flags;
760 	__u64 __resv[2];
761 };
762 
763 /*
764  * Register a fully sparse file space, rather than pass in an array of all
765  * -1 file descriptors.
766  */
767 #define IORING_RSRC_REGISTER_SPARSE	(1U << 0)
768 
769 struct io_uring_rsrc_register {
770 	__u32 nr;
771 	__u32 flags;
772 	__u64 resv2;
773 	__aligned_u64 data;
774 	__aligned_u64 tags;
775 };
776 
777 struct io_uring_rsrc_update {
778 	__u32 offset;
779 	__u32 resv;
780 	__aligned_u64 data;
781 };
782 
783 struct io_uring_rsrc_update2 {
784 	__u32 offset;
785 	__u32 resv;
786 	__aligned_u64 data;
787 	__aligned_u64 tags;
788 	__u32 nr;
789 	__u32 resv2;
790 };
791 
792 /* Skip updating fd indexes set to this value in the fd table */
793 #define IORING_REGISTER_FILES_SKIP	(-2)
794 
795 #define IO_URING_OP_SUPPORTED	(1U << 0)
796 
797 struct io_uring_probe_op {
798 	__u8 op;
799 	__u8 resv;
800 	__u16 flags;	/* IO_URING_OP_* flags */
801 	__u32 resv2;
802 };
803 
804 struct io_uring_probe {
805 	__u8 last_op;	/* last opcode supported */
806 	__u8 ops_len;	/* length of ops[] array below */
807 	__u16 resv;
808 	__u32 resv2[3];
809 	struct io_uring_probe_op ops[];
810 };
811 
812 struct io_uring_restriction {
813 	__u16 opcode;
814 	union {
815 		__u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
816 		__u8 sqe_op;      /* IORING_RESTRICTION_SQE_OP */
817 		__u8 sqe_flags;   /* IORING_RESTRICTION_SQE_FLAGS_* */
818 	};
819 	__u8 resv;
820 	__u32 resv2[3];
821 };
822 
823 struct io_uring_task_restriction {
824 	__u16 flags;
825 	__u16 nr_res;
826 	__u32 resv[3];
827 	__DECLARE_FLEX_ARRAY(struct io_uring_restriction, restrictions);
828 };
829 
830 struct io_uring_clock_register {
831 	__u32	clockid;
832 	__u32	__resv[3];
833 };
834 
835 enum {
836 	IORING_REGISTER_SRC_REGISTERED	= (1U << 0),
837 	IORING_REGISTER_DST_REPLACE	= (1U << 1),
838 };
839 
840 struct io_uring_clone_buffers {
841 	__u32	src_fd;
842 	__u32	flags;
843 	__u32	src_off;
844 	__u32	dst_off;
845 	__u32	nr;
846 	__u32	pad[3];
847 };
848 
849 struct io_uring_buf {
850 	__u64	addr;
851 	__u32	len;
852 	__u16	bid;
853 	__u16	resv;
854 };
855 
856 struct io_uring_buf_ring {
857 	union {
858 		/*
859 		 * To avoid spilling into more pages than we need to, the
860 		 * ring tail is overlaid with the io_uring_buf->resv field.
861 		 */
862 		struct {
863 			__u64	resv1;
864 			__u32	resv2;
865 			__u16	resv3;
866 			__u16	tail;
867 		};
868 		__DECLARE_FLEX_ARRAY(struct io_uring_buf, bufs);
869 	};
870 };
871 
872 /*
873  * Flags for IORING_REGISTER_PBUF_RING.
874  *
875  * IOU_PBUF_RING_MMAP:	If set, kernel will allocate the memory for the ring.
876  *			The application must not set a ring_addr in struct
877  *			io_uring_buf_reg, instead it must subsequently call
878  *			mmap(2) with the offset set as:
879  *			IORING_OFF_PBUF_RING | (bgid << IORING_OFF_PBUF_SHIFT)
880  *			to get a virtual mapping for the ring.
881  * IOU_PBUF_RING_INC:	If set, buffers consumed from this buffer ring can be
882  *			consumed incrementally. Normally one (or more) buffers
883  *			are fully consumed. With incremental consumptions, it's
884  *			feasible to register big ranges of buffers, and each
885  *			use of it will consume only as much as it needs. This
886  *			requires that both the kernel and application keep
887  *			track of where the current read/recv index is at.
888  */
889 enum io_uring_register_pbuf_ring_flags {
890 	IOU_PBUF_RING_MMAP	= 1,
891 	IOU_PBUF_RING_INC	= 2,
892 };
893 
894 /* argument for IORING_(UN)REGISTER_PBUF_RING */
895 struct io_uring_buf_reg {
896 	__u64	ring_addr;
897 	__u32	ring_entries;
898 	__u16	bgid;
899 	__u16	flags;
900 	__u64	resv[3];
901 };
902 
903 /* argument for IORING_REGISTER_PBUF_STATUS */
904 struct io_uring_buf_status {
905 	__u32	buf_group;	/* input */
906 	__u32	head;		/* output */
907 	__u32	resv[8];
908 };
909 
910 enum io_uring_napi_op {
911 	/* register/ungister backward compatible opcode */
912 	IO_URING_NAPI_REGISTER_OP = 0,
913 
914 	/* opcodes to update napi_list when static tracking is used */
915 	IO_URING_NAPI_STATIC_ADD_ID = 1,
916 	IO_URING_NAPI_STATIC_DEL_ID = 2
917 };
918 
919 enum io_uring_napi_tracking_strategy {
920 	/* value must be 0 for backward compatibility */
921 	IO_URING_NAPI_TRACKING_DYNAMIC = 0,
922 	IO_URING_NAPI_TRACKING_STATIC = 1,
923 	IO_URING_NAPI_TRACKING_INACTIVE = 255
924 };
925 
926 /* argument for IORING_(UN)REGISTER_NAPI */
927 struct io_uring_napi {
928 	__u32	busy_poll_to;
929 	__u8	prefer_busy_poll;
930 
931 	/* a io_uring_napi_op value */
932 	__u8	opcode;
933 	__u8	pad[2];
934 
935 	/*
936 	 * for IO_URING_NAPI_REGISTER_OP, it is a
937 	 * io_uring_napi_tracking_strategy value.
938 	 *
939 	 * for IO_URING_NAPI_STATIC_ADD_ID/IO_URING_NAPI_STATIC_DEL_ID
940 	 * it is the napi id to add/del from napi_list.
941 	 */
942 	__u32	op_param;
943 	__u32	resv;
944 };
945 
946 /*
947  * io_uring_restriction->opcode values
948  */
949 enum io_uring_register_restriction_op {
950 	/* Allow an io_uring_register(2) opcode */
951 	IORING_RESTRICTION_REGISTER_OP		= 0,
952 
953 	/* Allow an sqe opcode */
954 	IORING_RESTRICTION_SQE_OP		= 1,
955 
956 	/* Allow sqe flags */
957 	IORING_RESTRICTION_SQE_FLAGS_ALLOWED	= 2,
958 
959 	/* Require sqe flags (these flags must be set on each submission) */
960 	IORING_RESTRICTION_SQE_FLAGS_REQUIRED	= 3,
961 
962 	IORING_RESTRICTION_LAST
963 };
964 
965 enum {
966 	IORING_REG_WAIT_TS		= (1U << 0),
967 };
968 
969 /*
970  * Argument for io_uring_enter(2) with
971  * IORING_GETEVENTS | IORING_ENTER_EXT_ARG_REG set, where the actual argument
972  * is an index into a previously registered fixed wait region described by
973  * the below structure.
974  */
975 struct io_uring_reg_wait {
976 	struct __kernel_timespec	ts;
977 	__u32				min_wait_usec;
978 	__u32				flags;
979 	__u64				sigmask;
980 	__u32				sigmask_sz;
981 	__u32				pad[3];
982 	__u64				pad2[2];
983 };
984 
985 /*
986  * Argument for io_uring_enter(2) with IORING_GETEVENTS | IORING_ENTER_EXT_ARG
987  */
988 struct io_uring_getevents_arg {
989 	__u64	sigmask;
990 	__u32	sigmask_sz;
991 	__u32	min_wait_usec;
992 	__u64	ts;
993 };
994 
995 /*
996  * Argument for IORING_REGISTER_SYNC_CANCEL
997  */
998 struct io_uring_sync_cancel_reg {
999 	__u64				addr;
1000 	__s32				fd;
1001 	__u32				flags;
1002 	struct __kernel_timespec	timeout;
1003 	__u8				opcode;
1004 	__u8				pad[7];
1005 	__u64				pad2[3];
1006 };
1007 
1008 /*
1009  * Argument for IORING_REGISTER_FILE_ALLOC_RANGE
1010  * The range is specified as [off, off + len)
1011  */
1012 struct io_uring_file_index_range {
1013 	__u32	off;
1014 	__u32	len;
1015 	__u64	resv;
1016 };
1017 
1018 struct io_uring_recvmsg_out {
1019 	__u32 namelen;
1020 	__u32 controllen;
1021 	__u32 payloadlen;
1022 	__u32 flags;
1023 };
1024 
1025 /*
1026  * Argument for IORING_OP_URING_CMD when file is a socket
1027  */
1028 enum io_uring_socket_op {
1029 	SOCKET_URING_OP_SIOCINQ		= 0,
1030 	SOCKET_URING_OP_SIOCOUTQ,
1031 	SOCKET_URING_OP_GETSOCKOPT,
1032 	SOCKET_URING_OP_SETSOCKOPT,
1033 	SOCKET_URING_OP_TX_TIMESTAMP,
1034 	SOCKET_URING_OP_GETSOCKNAME,
1035 };
1036 
1037 /*
1038  * SOCKET_URING_OP_TX_TIMESTAMP definitions
1039  */
1040 
1041 #define IORING_TIMESTAMP_HW_SHIFT	16
1042 /* The cqe->flags bit from which the timestamp type is stored */
1043 #define IORING_TIMESTAMP_TYPE_SHIFT	(IORING_TIMESTAMP_HW_SHIFT + 1)
1044 /* The cqe->flags flag signifying whether it's a hardware timestamp */
1045 #define IORING_CQE_F_TSTAMP_HW		((__u32)1 << IORING_TIMESTAMP_HW_SHIFT)
1046 
1047 struct io_timespec {
1048 	__u64		tv_sec;
1049 	__u64		tv_nsec;
1050 };
1051 
1052 /* Zero copy receive refill queue entry */
1053 struct io_uring_zcrx_rqe {
1054 	__u64	off;
1055 	__u32	len;
1056 	__u32	__pad;
1057 };
1058 
1059 struct io_uring_zcrx_cqe {
1060 	__u64	off;
1061 	__u64	__pad;
1062 };
1063 
1064 /* The bit from which area id is encoded into offsets */
1065 #define IORING_ZCRX_AREA_SHIFT	48
1066 #define IORING_ZCRX_AREA_MASK	(~(((__u64)1 << IORING_ZCRX_AREA_SHIFT) - 1))
1067 
1068 struct io_uring_zcrx_offsets {
1069 	__u32	head;
1070 	__u32	tail;
1071 	__u32	rqes;
1072 	__u32	__resv2;
1073 	__u64	__resv[2];
1074 };
1075 
1076 enum io_uring_zcrx_area_flags {
1077 	IORING_ZCRX_AREA_DMABUF		= 1,
1078 };
1079 
1080 struct io_uring_zcrx_area_reg {
1081 	__u64	addr;
1082 	__u64	len;
1083 	__u64	rq_area_token;
1084 	__u32	flags;
1085 	__u32	dmabuf_fd;
1086 	__u64	__resv2[2];
1087 };
1088 
1089 enum zcrx_reg_flags {
1090 	ZCRX_REG_IMPORT	= 1,
1091 };
1092 
1093 /*
1094  * Argument for IORING_REGISTER_ZCRX_IFQ
1095  */
1096 struct io_uring_zcrx_ifq_reg {
1097 	__u32	if_idx;
1098 	__u32	if_rxq;
1099 	__u32	rq_entries;
1100 	__u32	flags;
1101 
1102 	__u64	area_ptr; /* pointer to struct io_uring_zcrx_area_reg */
1103 	__u64	region_ptr; /* struct io_uring_region_desc * */
1104 
1105 	struct io_uring_zcrx_offsets offsets;
1106 	__u32	zcrx_id;
1107 	__u32	rx_buf_len;
1108 	__u64	__resv[3];
1109 };
1110 
1111 enum zcrx_ctrl_op {
1112 	ZCRX_CTRL_FLUSH_RQ,
1113 	ZCRX_CTRL_EXPORT,
1114 
1115 	__ZCRX_CTRL_LAST,
1116 };
1117 
1118 struct zcrx_ctrl_flush_rq {
1119 	__u64		__resv[6];
1120 };
1121 
1122 struct zcrx_ctrl_export {
1123 	__u32		zcrx_fd;
1124 	__u32 		__resv1[11];
1125 };
1126 
1127 struct zcrx_ctrl {
1128 	__u32	zcrx_id;
1129 	__u32	op; /* see enum zcrx_ctrl_op */
1130 	__u64	__resv[2];
1131 
1132 	union {
1133 		struct zcrx_ctrl_export		zc_export;
1134 		struct zcrx_ctrl_flush_rq	zc_flush;
1135 	};
1136 };
1137 
1138 #ifdef __cplusplus
1139 }
1140 #endif
1141 
1142 #endif
1143