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1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef __ASM_GENERIC_SEMBUF_H
3#define __ASM_GENERIC_SEMBUF_H
4
5#include <asm/bitsperlong.h>
6
7/*
8 * The semid64_ds structure for x86 architecture.
9 * Note extra padding because this structure is passed back and forth
10 * between kernel and user space.
11 *
12 * semid64_ds was originally meant to be architecture specific, but
13 * everyone just ended up making identical copies without specific
14 * optimizations, so we may just as well all use the same one.
15 *
16 * 64 bit architectures use a 64-bit __kernel_time_t here, while
17 * 32 bit architectures have a pair of unsigned long values.
18 * so they do not need the first two padding words.
19 *
20 * On big-endian systems, the padding is in the wrong place for
21 * historic reasons, so user space has to reconstruct a time_t
22 * value using
23 *
24 * user_semid_ds.sem_otime = kernel_semid64_ds.sem_otime +
25 * ((long long)kernel_semid64_ds.sem_otime_high << 32)
26 *
27 * Pad space is left for 2 miscellaneous 32-bit values
28 */
29struct semid64_ds {
30 struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
31#if __BITS_PER_LONG == 64
32 __kernel_time_t sem_otime; /* last semop time */
33 __kernel_time_t sem_ctime; /* last change time */
34#else
35 unsigned long sem_otime; /* last semop time */
36 unsigned long sem_otime_high;
37 unsigned long sem_ctime; /* last change time */
38 unsigned long sem_ctime_high;
39#endif
40 unsigned long sem_nsems; /* no. of semaphores in array */
41 unsigned long __unused3;
42 unsigned long __unused4;
43};
44
45#endif /* __ASM_GENERIC_SEMBUF_H */
1#ifndef __ASM_GENERIC_SEMBUF_H
2#define __ASM_GENERIC_SEMBUF_H
3
4#include <asm/bitsperlong.h>
5
6/*
7 * The semid64_ds structure for x86 architecture.
8 * Note extra padding because this structure is passed back and forth
9 * between kernel and user space.
10 *
11 * semid64_ds was originally meant to be architecture specific, but
12 * everyone just ended up making identical copies without specific
13 * optimizations, so we may just as well all use the same one.
14 *
15 * 64 bit architectures typically define a 64 bit __kernel_time_t,
16 * so they do not need the first two padding words.
17 * On big-endian systems, the padding is in the wrong place.
18 *
19 * Pad space is left for:
20 * - 64-bit time_t to solve y2038 problem
21 * - 2 miscellaneous 32-bit values
22 */
23struct semid64_ds {
24 struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
25 __kernel_time_t sem_otime; /* last semop time */
26#if __BITS_PER_LONG != 64
27 unsigned long __unused1;
28#endif
29 __kernel_time_t sem_ctime; /* last change time */
30#if __BITS_PER_LONG != 64
31 unsigned long __unused2;
32#endif
33 unsigned long sem_nsems; /* no. of semaphores in array */
34 unsigned long __unused3;
35 unsigned long __unused4;
36};
37
38#endif /* __ASM_GENERIC_SEMBUF_H */