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linux/include/asm-generic/shmbuf.h
Arnd Bergmann 2864d32be3 asm-generic: add generic sysv ipc headers
The ipc64 data structures were originally meant to
be architecture specific so that each architecture
could add their own optimizations for padding.

In the end, most of them just copied the x86 version,
and most got that wrong. UClibc expects the x86 anyway,
so we might just declare that the default and get
rid of the extra copies.

Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-11 21:02:15 +02:00

60 lines
1.7 KiB
C

#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 typically define a 64 bit __kernel_time_t,
* so they do not need the first two padding words.
* On big-endian systems, the padding is in the wrong place.
*
*
* Pad space is left for:
* - 64-bit time_t to solve y2038 problem
* - 2 miscellaneous 32-bit values
*/
struct shmid64_ds {
struct ipc64_perm shm_perm; /* operation perms */
size_t shm_segsz; /* size of segment (bytes) */
__kernel_time_t shm_atime; /* last attach time */
#if __BITS_PER_LONG != 64
unsigned long __unused1;
#endif
__kernel_time_t shm_dtime; /* last detach time */
#if __BITS_PER_LONG != 64
unsigned long __unused2;
#endif
__kernel_time_t shm_ctime; /* last change time */
#if __BITS_PER_LONG != 64
unsigned long __unused3;
#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 */