1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef __ASM_GENERIC_SHMBUF_H
3#define __ASM_GENERIC_SHMBUF_H
4
5#include <asm/bitsperlong.h>
6#include <asm/ipcbuf.h>
7#include <asm/posix_types.h>
8
9/*
10 * The shmid64_ds structure for x86 architecture.
11 * Note extra padding because this structure is passed back and forth
12 * between kernel and user space.
13 *
14 * shmid64_ds was originally meant to be architecture specific, but
15 * everyone just ended up making identical copies without specific
16 * optimizations, so we may just as well all use the same one.
17 *
18 * 64 bit architectures use a 64-bit long time field here, while
19 * 32 bit architectures have a pair of unsigned long values.
20 * On big-endian systems, the lower half is in the wrong place.
21 *
22 *
23 * Pad space is left for:
24 * - 2 miscellaneous 32-bit values
25 */
26
27struct shmid64_ds {
28	struct ipc64_perm	shm_perm;	/* operation perms */
29	__kernel_size_t		shm_segsz;	/* size of segment (bytes) */
30#if __BITS_PER_LONG == 64
31	long			shm_atime;	/* last attach time */
32	long			shm_dtime;	/* last detach time */
33	long			shm_ctime;	/* last change time */
34#else
35	unsigned long		shm_atime;	/* last attach time */
36	unsigned long		shm_atime_high;
37	unsigned long		shm_dtime;	/* last detach time */
38	unsigned long		shm_dtime_high;
39	unsigned long		shm_ctime;	/* last change time */
40	unsigned long		shm_ctime_high;
41#endif
42	__kernel_pid_t		shm_cpid;	/* pid of creator */
43	__kernel_pid_t		shm_lpid;	/* pid of last operator */
44	unsigned long		shm_nattch;	/* no. of current attaches */
45	unsigned long		__unused4;
46	unsigned long		__unused5;
47};
48
49struct shminfo64 {
50	unsigned long		shmmax;
51	unsigned long		shmmin;
52	unsigned long		shmmni;
53	unsigned long		shmseg;
54	unsigned long		shmall;
55	unsigned long		__unused1;
56	unsigned long		__unused2;
57	unsigned long		__unused3;
58	unsigned long		__unused4;
59};
60
61#endif /* __ASM_GENERIC_SHMBUF_H */
62