blob: 0bae010f1b64fb36086b31e993e99c6f7a738db6 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef __ASM_GENERIC_SEMBUF_H
#define __ASM_GENERIC_SEMBUF_H
#include <asm/bitsperlong.h>
/*
* The semid64_ds structure for x86 architecture.
* Note extra padding because this structure is passed back and forth
* between kernel and user space.
*
* semid64_ds was originally meant to be architecture specific, but
* everyone just ended up making identical copies without specific
* optimizations, so we may just as well all use the same one.
*
* 64 bit architectures use a 64-bit __kernel_time_t here, while
* 32 bit architectures have a pair of unsigned long values.
* so they do not need the first two padding words.
*
* On big-endian systems, the padding is in the wrong place for
* historic reasons, so user space has to reconstruct a time_t
* value using
*
* user_semid_ds.sem_otime = kernel_semid64_ds.sem_otime +
* ((long long)kernel_semid64_ds.sem_otime_high << 32)
*
* Pad space is left for 2 miscellaneous 32-bit values
*/
struct semid64_ds {
struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
#if __BITS_PER_LONG == 64
__kernel_time_t sem_otime; /* last semop time */
__kernel_time_t sem_ctime; /* last change time */
#else
unsigned long sem_otime; /* last semop time */
unsigned long sem_otime_high;
unsigned long sem_ctime; /* last change time */
unsigned long sem_ctime_high;
#endif
unsigned long sem_nsems; /* no. of semaphores in array */
unsigned long __unused3;
unsigned long __unused4;
};
#endif /* __ASM_GENERIC_SEMBUF_H */
|
