Commit | Line | Data |
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e1ad7468 DL |
1 | /* |
2 | * include/linux/eventfd.h | |
3 | * | |
4 | * Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org> | |
5 | * | |
6 | */ | |
7 | ||
8 | #ifndef _LINUX_EVENTFD_H | |
9 | #define _LINUX_EVENTFD_H | |
10 | ||
b087498e | 11 | #include <linux/fcntl.h> |
13389010 | 12 | #include <linux/file.h> |
b087498e | 13 | |
bcd0b235 DL |
14 | /* |
15 | * CAREFUL: Check include/asm-generic/fcntl.h when defining | |
16 | * new flags, since they might collide with O_* ones. We want | |
17 | * to re-use O_* flags that couldn't possibly have a meaning | |
18 | * from eventfd, in order to leave a free define-space for | |
19 | * shared O_* flags. | |
20 | */ | |
21 | #define EFD_SEMAPHORE (1 << 0) | |
b087498e | 22 | #define EFD_CLOEXEC O_CLOEXEC |
e7d476df | 23 | #define EFD_NONBLOCK O_NONBLOCK |
b087498e | 24 | |
bcd0b235 DL |
25 | #define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK) |
26 | #define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE) | |
27 | ||
13389010 DL |
28 | #ifdef CONFIG_EVENTFD |
29 | ||
30 | struct eventfd_ctx *eventfd_ctx_get(struct eventfd_ctx *ctx); | |
31 | void eventfd_ctx_put(struct eventfd_ctx *ctx); | |
e1ad7468 | 32 | struct file *eventfd_fget(int fd); |
13389010 DL |
33 | struct eventfd_ctx *eventfd_ctx_fdget(int fd); |
34 | struct eventfd_ctx *eventfd_ctx_fileget(struct file *file); | |
35 | int eventfd_signal(struct eventfd_ctx *ctx, int n); | |
e1ad7468 DL |
36 | |
37 | #else /* CONFIG_EVENTFD */ | |
38 | ||
13389010 DL |
39 | /* |
40 | * Ugly ugly ugly error layer to support modules that uses eventfd but | |
41 | * pretend to work in !CONFIG_EVENTFD configurations. Namely, AIO. | |
42 | */ | |
43 | static inline struct eventfd_ctx *eventfd_ctx_fdget(int fd) | |
44 | { | |
45 | return ERR_PTR(-ENOSYS); | |
46 | } | |
47 | ||
48 | static inline int eventfd_signal(struct eventfd_ctx *ctx, int n) | |
49 | { | |
50 | return -ENOSYS; | |
51 | } | |
52 | ||
53 | static inline void eventfd_ctx_put(struct eventfd_ctx *ctx) | |
54 | { | |
55 | ||
56 | } | |
e1ad7468 | 57 | |
13389010 | 58 | #endif |
e1ad7468 | 59 | |
e1ad7468 DL |
60 | #endif /* _LINUX_EVENTFD_H */ |
61 |