* Copyright (c) 2002, 2006, 2009 The NetBSD Foundation, Inc.

/* $NetBSD: mutex.h,v 1.10 2023/07/12 12:50:13 riastradh Exp $ */

/*-
* Copyright (c) 2002, 2006, 2009 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe and Andrew Doran.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef _X86_MUTEX_H_
#define _X86_MUTEX_H_

#include <sys/types.h>

#ifdef _KERNEL
#include <machine/intr.h>
#endif

struct kmutex {
union {
volatile uintptr_t mtxa_owner;
#ifdef _KERNEL
struct {
volatile uint8_t mtxs_dummy;
ipl_cookie_t mtxs_ipl;
__cpu_simple_lock_t mtxs_lock;
volatile uint8_t mtxs_unused;
} s;
#endif
} u;
};

#ifdef __MUTEX_PRIVATE

#define mtx_owner u.mtxa_owner
#define mtx_ipl u.s.mtxs_ipl
#define mtx_lock u.s.mtxs_lock

#define __HAVE_MUTEX_STUBS 1
#define __HAVE_SPIN_MUTEX_STUBS 1
#define __HAVE_SIMPLE_MUTEXES 1

#define MUTEX_CAS(p, o, n) \
(_atomic_cas_ulong((volatile unsigned long *)(p), (o), (n)) == (o))

unsigned long _atomic_cas_ulong(volatile unsigned long *,
unsigned long, unsigned long);

#endif /* __MUTEX_PRIVATE */

#endif /* _X86_MUTEX_H_ */