1/*
2 *  include/linux/eventpoll.h ( Efficient event polling implementation )
3 *  Copyright (C) 2001,...,2006	 Davide Libenzi
4 *
5 *  This program is free software; you can redistribute it and/or modify
6 *  it under the terms of the GNU General Public License as published by
7 *  the Free Software Foundation; either version 2 of the License, or
8 *  (at your option) any later version.
9 *
10 *  Davide Libenzi <davidel@xmailserver.org>
11 *
12 */
13
14#ifndef _UAPI_LINUX_EVENTPOLL_H
15#define _UAPI_LINUX_EVENTPOLL_H
16
17/* For O_CLOEXEC */
18#include <linux/fcntl.h>
19#include <linux/types.h>
20
21/* Flags for epoll_create1.  */
22#define EPOLL_CLOEXEC O_CLOEXEC
23
24/* Valid opcodes to issue to sys_epoll_ctl() */
25#define EPOLL_CTL_ADD 1
26#define EPOLL_CTL_DEL 2
27#define EPOLL_CTL_MOD 3
28
29/*
30 * Request the handling of system wakeup events so as to prevent system suspends
31 * from happening while those events are being processed.
32 *
33 * Assuming neither EPOLLET nor EPOLLONESHOT is set, system suspends will not be
34 * re-allowed until epoll_wait is called again after consuming the wakeup
35 * event(s).
36 *
37 * Requires CAP_BLOCK_SUSPEND
38 */
39#define EPOLLWAKEUP (1 << 29)
40
41/* Set the One Shot behaviour for the target file descriptor */
42#define EPOLLONESHOT (1 << 30)
43
44/* Set the Edge Triggered behaviour for the target file descriptor */
45#define EPOLLET (1 << 31)
46
47/*
48 * On x86-64 make the 64bit structure have the same alignment as the
49 * 32bit structure. This makes 32bit emulation easier.
50 *
51 * UML/x86_64 needs the same packing as x86_64
52 */
53#ifdef __x86_64__
54#define EPOLL_PACKED __attribute__((packed))
55#else
56#define EPOLL_PACKED
57#endif
58
59struct epoll_event {
60	__u32 events;
61	__u64 data;
62} EPOLL_PACKED;
63
64#ifdef CONFIG_PM_SLEEP
65static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
66{
67	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
68		epev->events &= ~EPOLLWAKEUP;
69}
70#else
71static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
72{
73	epev->events &= ~EPOLLWAKEUP;
74}
75#endif
76#endif /* _UAPI_LINUX_EVENTPOLL_H */
77