shmbuf.h (3eb66e91a25497065c5322b1268cbc3953642227) shmbuf.h (caf5e32d4ea7253820f38dd7c429f8d4a8019c5f)
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
7/*
8 * The shmid64_ds structure for x86 architecture.
9 * Note extra padding because this structure is passed back and forth
10 * between kernel and user space.
11 *
12 * shmid64_ds was originally meant to be architecture specific, but
13 * everyone just ended up making identical copies without specific
14 * optimizations, so we may just as well all use the same one.
15 *
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
7/*
8 * The shmid64_ds structure for x86 architecture.
9 * Note extra padding because this structure is passed back and forth
10 * between kernel and user space.
11 *
12 * shmid64_ds was originally meant to be architecture specific, but
13 * everyone just ended up making identical copies without specific
14 * optimizations, so we may just as well all use the same one.
15 *
16 * 64 bit architectures typically define a 64 bit __kernel_time_t,
17 * so they do not need the first two padding words.
18 * On big-endian systems, the padding is in the wrong place.
16 * 64 bit architectures use a 64-bit long time field here, while
17 * 32 bit architectures have a pair of unsigned long values.
18 * On big-endian systems, the lower half is in the wrong place.
19 *
20 *
21 * Pad space is left for:
22 * - 2 miscellaneous 32-bit values
23 */
24
25struct shmid64_ds {
26 struct ipc64_perm shm_perm; /* operation perms */
27 size_t shm_segsz; /* size of segment (bytes) */
28#if __BITS_PER_LONG == 64
19 *
20 *
21 * Pad space is left for:
22 * - 2 miscellaneous 32-bit values
23 */
24
25struct shmid64_ds {
26 struct ipc64_perm shm_perm; /* operation perms */
27 size_t shm_segsz; /* size of segment (bytes) */
28#if __BITS_PER_LONG == 64
29 __kernel_time_t shm_atime; /* last attach time */
30 __kernel_time_t shm_dtime; /* last detach time */
31 __kernel_time_t shm_ctime; /* last change time */
29 long shm_atime; /* last attach time */
30 long shm_dtime; /* last detach time */
31 long shm_ctime; /* last change time */
32#else
33 unsigned long shm_atime; /* last attach time */
34 unsigned long shm_atime_high;
35 unsigned long shm_dtime; /* last detach time */
36 unsigned long shm_dtime_high;
37 unsigned long shm_ctime; /* last change time */
38 unsigned long shm_ctime_high;
39#endif

--- 20 unchanged lines hidden --- 		32#else
33 unsigned long shm_atime; /* last attach time */
34 unsigned long shm_atime_high;
35 unsigned long shm_dtime; /* last detach time */
36 unsigned long shm_dtime_high;
37 unsigned long shm_ctime; /* last change time */
38 unsigned long shm_ctime_high;
39#endif

--- 20 unchanged lines hidden ---