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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> 
#include <asm/ipcbuf.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 long time field here, while 
 * 32 bit architectures have a pair of unsigned long values. 
 * 
 * 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 
	long		sem_otime;	/* last semop time */ 
	long		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 */