alistair23-linux/include/linux/eventfd.h
Arnd Bergmann fa3fc2ad99 include/linux/eventfd.h: include linux/errno.h
The new gasket staging driver ran into a randconfig build failure when
CONFIG_EVENTFD is disabled:

  In file included from drivers/staging/gasket/gasket_interrupt.h:11,
                   from drivers/staging/gasket/gasket_interrupt.c:4:
  include/linux/eventfd.h: In function 'eventfd_ctx_fdget':
  include/linux/eventfd.h:51:9: error: implicit declaration of function 'ERR_PTR' [-Werror=implicit-function-declaration]

I can't see anything wrong with including eventfd.h before err.h, so the
easiest fix is to make it possible to do this by including the file
where it is needed.

Link: http://lkml.kernel.org/r/20180724110737.3985088-1-arnd@arndb.de
Fixes: 9a69f5087c ("drivers/staging: Gasket driver framework + Apex driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-26 19:38:03 -07:00

75 lines
1.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* include/linux/eventfd.h
*
* Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
*
*/
#ifndef _LINUX_EVENTFD_H
#define _LINUX_EVENTFD_H
#include <linux/fcntl.h>
#include <linux/wait.h>
#include <linux/err.h>
/*
* CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining
* new flags, since they might collide with O_* ones. We want
* to re-use O_* flags that couldn't possibly have a meaning
* from eventfd, in order to leave a free define-space for
* shared O_* flags.
*/
#define EFD_SEMAPHORE (1 << 0)
#define EFD_CLOEXEC O_CLOEXEC
#define EFD_NONBLOCK O_NONBLOCK
#define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
#define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE)
struct eventfd_ctx;
struct file;
#ifdef CONFIG_EVENTFD
void eventfd_ctx_put(struct eventfd_ctx *ctx);
struct file *eventfd_fget(int fd);
struct eventfd_ctx *eventfd_ctx_fdget(int fd);
struct eventfd_ctx *eventfd_ctx_fileget(struct file *file);
__u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n);
int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_entry_t *wait,
__u64 *cnt);
#else /* CONFIG_EVENTFD */
/*
* Ugly ugly ugly error layer to support modules that uses eventfd but
* pretend to work in !CONFIG_EVENTFD configurations. Namely, AIO.
*/
static inline struct eventfd_ctx *eventfd_ctx_fdget(int fd)
{
return ERR_PTR(-ENOSYS);
}
static inline int eventfd_signal(struct eventfd_ctx *ctx, int n)
{
return -ENOSYS;
}
static inline void eventfd_ctx_put(struct eventfd_ctx *ctx)
{
}
static inline int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx,
wait_queue_entry_t *wait, __u64 *cnt)
{
return -ENOSYS;
}
#endif
#endif /* _LINUX_EVENTFD_H */