]>
Commit | Line | Data |
---|---|---|
b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
e1ad7468 DL |
2 | /* |
3 | * include/linux/eventfd.h | |
4 | * | |
5 | * Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org> | |
6 | * | |
7 | */ | |
8 | ||
9 | #ifndef _LINUX_EVENTFD_H | |
10 | #define _LINUX_EVENTFD_H | |
11 | ||
b087498e | 12 | #include <linux/fcntl.h> |
cb289d62 | 13 | #include <linux/wait.h> |
b087498e | 14 | |
bcd0b235 | 15 | /* |
1d730c49 | 16 | * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining |
bcd0b235 DL |
17 | * new flags, since they might collide with O_* ones. We want |
18 | * to re-use O_* flags that couldn't possibly have a meaning | |
19 | * from eventfd, in order to leave a free define-space for | |
20 | * shared O_* flags. | |
21 | */ | |
22 | #define EFD_SEMAPHORE (1 << 0) | |
b087498e | 23 | #define EFD_CLOEXEC O_CLOEXEC |
e7d476df | 24 | #define EFD_NONBLOCK O_NONBLOCK |
b087498e | 25 | |
bcd0b235 DL |
26 | #define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK) |
27 | #define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE) | |
28 | ||
4e10f3c9 AV |
29 | struct file; |
30 | ||
13389010 DL |
31 | #ifdef CONFIG_EVENTFD |
32 | ||
562787a5 | 33 | struct file *eventfd_file_create(unsigned int count, int flags); |
13389010 DL |
34 | struct eventfd_ctx *eventfd_ctx_get(struct eventfd_ctx *ctx); |
35 | void eventfd_ctx_put(struct eventfd_ctx *ctx); | |
e1ad7468 | 36 | struct file *eventfd_fget(int fd); |
13389010 DL |
37 | struct eventfd_ctx *eventfd_ctx_fdget(int fd); |
38 | struct eventfd_ctx *eventfd_ctx_fileget(struct file *file); | |
ee62c6b2 | 39 | __u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n); |
cb289d62 | 40 | ssize_t eventfd_ctx_read(struct eventfd_ctx *ctx, int no_wait, __u64 *cnt); |
ac6424b9 | 41 | int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_entry_t *wait, |
cb289d62 | 42 | __u64 *cnt); |
e1ad7468 DL |
43 | |
44 | #else /* CONFIG_EVENTFD */ | |
45 | ||
13389010 DL |
46 | /* |
47 | * Ugly ugly ugly error layer to support modules that uses eventfd but | |
48 | * pretend to work in !CONFIG_EVENTFD configurations. Namely, AIO. | |
49 | */ | |
562787a5 DL |
50 | static inline struct file *eventfd_file_create(unsigned int count, int flags) |
51 | { | |
52 | return ERR_PTR(-ENOSYS); | |
53 | } | |
54 | ||
13389010 DL |
55 | static inline struct eventfd_ctx *eventfd_ctx_fdget(int fd) |
56 | { | |
57 | return ERR_PTR(-ENOSYS); | |
58 | } | |
59 | ||
60 | static inline int eventfd_signal(struct eventfd_ctx *ctx, int n) | |
61 | { | |
62 | return -ENOSYS; | |
63 | } | |
64 | ||
65 | static inline void eventfd_ctx_put(struct eventfd_ctx *ctx) | |
66 | { | |
67 | ||
68 | } | |
e1ad7468 | 69 | |
cb289d62 DL |
70 | static inline ssize_t eventfd_ctx_read(struct eventfd_ctx *ctx, int no_wait, |
71 | __u64 *cnt) | |
72 | { | |
73 | return -ENOSYS; | |
74 | } | |
75 | ||
76 | static inline int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, | |
ac6424b9 | 77 | wait_queue_entry_t *wait, __u64 *cnt) |
cb289d62 DL |
78 | { |
79 | return -ENOSYS; | |
80 | } | |
81 | ||
13389010 | 82 | #endif |
e1ad7468 | 83 | |
e1ad7468 DL |
84 | #endif /* _LINUX_EVENTFD_H */ |
85 |