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> |
cb289d62 | 12 | #include <linux/wait.h> |
b087498e | 13 | |
bcd0b235 | 14 | /* |
1d730c49 | 15 | * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining |
bcd0b235 DL |
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 | ||
4e10f3c9 AV |
28 | struct file; |
29 | ||
13389010 DL |
30 | #ifdef CONFIG_EVENTFD |
31 | ||
562787a5 | 32 | struct file *eventfd_file_create(unsigned int count, int flags); |
13389010 DL |
33 | struct eventfd_ctx *eventfd_ctx_get(struct eventfd_ctx *ctx); |
34 | void eventfd_ctx_put(struct eventfd_ctx *ctx); | |
e1ad7468 | 35 | struct file *eventfd_fget(int fd); |
13389010 DL |
36 | struct eventfd_ctx *eventfd_ctx_fdget(int fd); |
37 | struct eventfd_ctx *eventfd_ctx_fileget(struct file *file); | |
ee62c6b2 | 38 | __u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n); |
cb289d62 DL |
39 | ssize_t eventfd_ctx_read(struct eventfd_ctx *ctx, int no_wait, __u64 *cnt); |
40 | int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_t *wait, | |
41 | __u64 *cnt); | |
e1ad7468 DL |
42 | |
43 | #else /* CONFIG_EVENTFD */ | |
44 | ||
13389010 DL |
45 | /* |
46 | * Ugly ugly ugly error layer to support modules that uses eventfd but | |
47 | * pretend to work in !CONFIG_EVENTFD configurations. Namely, AIO. | |
48 | */ | |
562787a5 DL |
49 | static inline struct file *eventfd_file_create(unsigned int count, int flags) |
50 | { | |
51 | return ERR_PTR(-ENOSYS); | |
52 | } | |
53 | ||
13389010 DL |
54 | static inline struct eventfd_ctx *eventfd_ctx_fdget(int fd) |
55 | { | |
56 | return ERR_PTR(-ENOSYS); | |
57 | } | |
58 | ||
59 | static inline int eventfd_signal(struct eventfd_ctx *ctx, int n) | |
60 | { | |
61 | return -ENOSYS; | |
62 | } | |
63 | ||
64 | static inline void eventfd_ctx_put(struct eventfd_ctx *ctx) | |
65 | { | |
66 | ||
67 | } | |
e1ad7468 | 68 | |
cb289d62 DL |
69 | static inline ssize_t eventfd_ctx_read(struct eventfd_ctx *ctx, int no_wait, |
70 | __u64 *cnt) | |
71 | { | |
72 | return -ENOSYS; | |
73 | } | |
74 | ||
75 | static inline int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, | |
76 | wait_queue_t *wait, __u64 *cnt) | |
77 | { | |
78 | return -ENOSYS; | |
79 | } | |
80 | ||
13389010 | 81 | #endif |
e1ad7468 | 82 | |
e1ad7468 DL |
83 | #endif /* _LINUX_EVENTFD_H */ |
84 |