linux/arch/xtensa/include/uapi/asm/shmbuf.h
Arnd Bergmann b497ef570e y2038: xtensa: Extend sysvipc data structures
xtensa, uses a nonstandard variation of the generic sysvipc
data structures, intended to have the padding moved around
so it can deal with big-endian 32-bit user space that has
64-bit time_t.

xtensa tries hard to define the structures so they work
in both big-endian and little-endian systems with padding
on the right side.
However, they only succeeded for for two of the three structures,
and their struct shmid64_ds ended up being defined in two
identical copies, and the big-endian one is wrong.

This takes just take the same approach here that we have for
the asm-generic headers and adds separate 32-bit fields for the
upper halves of the timestamps, to let libc deal with the mess
in user space.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-04-20 16:20:15 +02:00

52 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
* include/asm-xtensa/shmbuf.h
*
* The shmid64_ds structure for Xtensa architecture.
* Note extra padding because this structure is passed back and forth
* between kernel and user space, but the padding is on the wrong
* side for big-endian xtensa, for historic reasons.
*
* Pad space is left for:
* - 2 miscellaneous 32-bit values
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*/
#ifndef _XTENSA_SHMBUF_H
#define _XTENSA_SHMBUF_H
struct shmid64_ds {
struct ipc64_perm shm_perm; /* operation perms */
size_t shm_segsz; /* size of segment (bytes) */
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;
__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 /* _XTENSA_SHMBUF_H */