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/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef __ASM_GENERIC_SHMBUF_H
#define __ASM_GENERIC_SHMBUF_H

#include <asm/bitsperlong.h>
#include <asm/ipcbuf.h>
#include <asm/posix_types.h>

/*
 * The shmid64_ds structure for x86 architecture.
 * Note extra padding because this structure is passed back and forth
 * between kernel and user space.
 *
 * shmid64_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 lower half is in the wrong place.
 *
 *
 * Pad space is left for:
 * - 2 miscellaneous 32-bit values
 */

struct shmid64_ds {
	struct ipc64_perm shm_perm; /* operation perms */
	__kernel_size_t shm_segsz;  /* size of segment (bytes) */
#if __BITS_PER_LONG == 64
	long shm_atime; /* last attach time */
	long shm_dtime; /* last detach time */
	long shm_ctime; /* last change time */
#else
	unsigned long shm_atime; /* last attach time */
	unsigned long shm_atime_high;
	unsigned long shm_dtime; /* last detach time */
	unsigned long shm_dtime_high;
	unsigned long shm_ctime; /* last change time */
	unsigned long shm_ctime_high;
#endif
	__kernel_pid_t shm_cpid;  /* pid of creator */
	__kernel_pid_t shm_lpid;  /* pid of last operator */
	unsigned long shm_nattch; /* no. of current attaches */
	unsigned long __unused4;
	unsigned long __unused5;
};

struct shminfo64 {
	unsigned long shmmax;
	unsigned long shmmin;
	unsigned long shmmni;
	unsigned long shmseg;
	unsigned long shmall;
	unsigned long __unused1;
	unsigned long __unused2;
	unsigned long __unused3;
	unsigned long __unused4;
};

#endif /* __ASM_GENERIC_SHMBUF_H */