xref: /netbsd-src/sys/arch/x86/include/mutex.h (revision a88454562984bb90edf6581e332f43e4b38e23a1)
1 /*	$NetBSD: mutex.h,v 1.10 2023/07/12 12:50:13 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002, 2006, 2009 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe and Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _X86_MUTEX_H_
33 #define	_X86_MUTEX_H_
34 
35 #include <sys/types.h>
36 
37 #ifdef _KERNEL
38 #include <machine/intr.h>
39 #endif
40 
41 struct kmutex {
42 	union {
43 		volatile uintptr_t	mtxa_owner;
44 #ifdef _KERNEL
45 		struct {
46 			volatile uint8_t	mtxs_dummy;
47 			ipl_cookie_t		mtxs_ipl;
48                         __cpu_simple_lock_t	mtxs_lock;
49 			volatile uint8_t	mtxs_unused;
50 		} s;
51 #endif
52 	} u;
53 };
54 
55 #ifdef __MUTEX_PRIVATE
56 
57 #define	mtx_owner 			u.mtxa_owner
58 #define	mtx_ipl 			u.s.mtxs_ipl
59 #define	mtx_lock			u.s.mtxs_lock
60 
61 #define __HAVE_MUTEX_STUBS		1
62 #define __HAVE_SPIN_MUTEX_STUBS		1
63 #define	__HAVE_SIMPLE_MUTEXES		1
64 
65 #define	MUTEX_CAS(p, o, n)		\
66     (_atomic_cas_ulong((volatile unsigned long *)(p), (o), (n)) == (o))
67 
68 unsigned long	_atomic_cas_ulong(volatile unsigned long *,
69     unsigned long, unsigned long);
70 
71 #endif	/* __MUTEX_PRIVATE */
72 
73 #endif /* _X86_MUTEX_H_ */
74