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/*
* Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
#include <linux/time.h>
#include <linux/sched.h>
#include <asm/system.h>
#include <linux/interrupt.h>
#include <asm/current.h>
#include <linux/module.h> /* for EXPORT_SYMBOL */
#include <linux/xfs_support/support.h>
/* Mutex locks ------------------------------------------------------ */
void _mutex_init( mutex_t *mutex)
{
mutex->state = 1;
sema_init( &mutex->sema, 1 );
}
void _mutex_destroy( mutex_t *mutex)
{
mutex->state = 0xdead;
sema_init( &mutex->sema, -99); /* Anyone using it again will block */
}
void _mutex_lock( mutex_t *mutex)
{
mutex->state--;
down( &mutex->sema );
}
void _mutex_unlock( mutex_t *mutex)
{
mutex->state++;
up( &mutex->sema );
}
int _mutex_trylock( mutex_t *mutex)
{
int ret;
ret = down_trylock( &mutex->sema );
if (ret == 0) {
mutex->state--;
}
return (ret==0) ? 1 : 0;
}
EXPORT_SYMBOL(_mutex_init);
EXPORT_SYMBOL(_mutex_lock);
EXPORT_SYMBOL(_mutex_unlock);
EXPORT_SYMBOL(_mutex_trylock);
EXPORT_SYMBOL(_mutex_destroy);
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