aboutsummaryrefslogtreecommitdiffstats
path: root/include/uapi/asm-generic/shmbuf.h
blob: 2bab955e0fed6a3166e33b2bed49ed3415748497 (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
46
47
48
49
50
51
52
53
54
55
56
57
58
59
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef __ASM_GENERIC_SHMBUF_H
#define __ASM_GENERIC_SHMBUF_H

#include <asm/bitsperlong.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 */
	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 */