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- /* 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 */
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