1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2/*
3 * include/linux/eventpoll.h ( Efficient event polling implementation )
4 * Copyright (C) 2001,...,2006 Davide Libenzi
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * Davide Libenzi <davidel@xmailserver.org>
12 *
13 */
14
15#ifndef _UAPI_LINUX_EVENTPOLL_H
16#define _UAPI_LINUX_EVENTPOLL_H
17
18/* For O_CLOEXEC */
19#include <linux/fcntl.h>
20#include <linux/types.h>
21
22/* Flags for epoll_create1. */
23#define EPOLL_CLOEXEC O_CLOEXEC
24
25/* Valid opcodes to issue to sys_epoll_ctl() */
26#define EPOLL_CTL_ADD 1
27#define EPOLL_CTL_DEL 2
28#define EPOLL_CTL_MOD 3
29
30/* Epoll event masks */
31#define EPOLLIN (__force __poll_t)0x00000001
32#define EPOLLPRI (__force __poll_t)0x00000002
33#define EPOLLOUT (__force __poll_t)0x00000004
34#define EPOLLERR (__force __poll_t)0x00000008
35#define EPOLLHUP (__force __poll_t)0x00000010
36#define EPOLLNVAL (__force __poll_t)0x00000020
37#define EPOLLRDNORM (__force __poll_t)0x00000040
38#define EPOLLRDBAND (__force __poll_t)0x00000080
39#define EPOLLWRNORM (__force __poll_t)0x00000100
40#define EPOLLWRBAND (__force __poll_t)0x00000200
41#define EPOLLMSG (__force __poll_t)0x00000400
42#define EPOLLRDHUP (__force __poll_t)0x00002000
43
44/*
45 * Internal flag - wakeup generated by io_uring, used to detect recursion back
46 * into the io_uring poll handler.
47 */
48#define EPOLL_URING_WAKE ((__force __poll_t)(1U << 27))
49
50/* Set exclusive wakeup mode for the target file descriptor */
51#define EPOLLEXCLUSIVE ((__force __poll_t)(1U << 28))
52
53/*
54 * Request the handling of system wakeup events so as to prevent system suspends
55 * from happening while those events are being processed.
56 *
57 * Assuming neither EPOLLET nor EPOLLONESHOT is set, system suspends will not be
58 * re-allowed until epoll_wait is called again after consuming the wakeup
59 * event(s).
60 *
61 * Requires CAP_BLOCK_SUSPEND
62 */
63#define EPOLLWAKEUP ((__force __poll_t)(1U << 29))
64
65/* Set the One Shot behaviour for the target file descriptor */
66#define EPOLLONESHOT ((__force __poll_t)(1U << 30))
67
68/* Set the Edge Triggered behaviour for the target file descriptor */
69#define EPOLLET ((__force __poll_t)(1U << 31))
70
71/*
72 * On x86-64 make the 64bit structure have the same alignment as the
73 * 32bit structure. This makes 32bit emulation easier.
74 *
75 * UML/x86_64 needs the same packing as x86_64
76 */
77#ifdef __x86_64__
78#define EPOLL_PACKED __attribute__((packed))
79#else
80#define EPOLL_PACKED
81#endif
82
83struct epoll_event {
84 __poll_t events;
85 __u64 data;
86} EPOLL_PACKED;
87
88struct epoll_params {
89 __u32 busy_poll_usecs;
90 __u16 busy_poll_budget;
91 __u8 prefer_busy_poll;
92
93 /* pad the struct to a multiple of 64bits */
94 __u8 __pad;
95};
96
97#define EPOLL_IOC_TYPE 0x8A
98#define EPIOCSPARAMS _IOW(EPOLL_IOC_TYPE, 0x01, struct epoll_params)
99#define EPIOCGPARAMS _IOR(EPOLL_IOC_TYPE, 0x02, struct epoll_params)
100
101#endif /* _UAPI_LINUX_EVENTPOLL_H */
102