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