Line data    Source code

       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             : 
      83             : struct epoll_event {
      84             :         __poll_t events;
      85             :         __u64 data;
      86             : } EPOLL_PACKED;
      87             : 
      88             : #ifdef CONFIG_PM_SLEEP
      89           0 : static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
      90             : {
      91           0 :         if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
      92           0 :                 epev->events &= ~EPOLLWAKEUP;
      93           0 : }
      94             : #else
      95             : static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
      96             : {
      97             :         epev->events &= ~EPOLLWAKEUP;
      98             : }
      99             : #endif
     100             : #endif /* _UAPI_LINUX_EVENTPOLL_H */