1 /*	$NetBSD: mutex.h,v 1.7 2014/08/23 08:03:33 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Taylor R. Campbell.
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 _LINUX_MUTEX_H_
33 #define _LINUX_MUTEX_H_
34 
35 #include <sys/mutex.h>
36 
37 #include <lib/libkern/libkern.h> /* KASSERT */
38 
39 #define	__acquires(lock)	/* XXX lockdep stuff */
40 #define	__releases(lock)	/* XXX lockdep stuff */
41 
42 struct mutex {
43 	kmutex_t mtx_lock;
44 };
45 
46 struct lock_class_key {
47 };
48 
49 /* Name collision.  Pooh.  */
50 static inline void
linux_mutex_init(struct mutex * mutex)51 linux_mutex_init(struct mutex *mutex)
52 {
53 	mutex_init(&mutex->mtx_lock, MUTEX_DEFAULT, IPL_NONE);
54 }
55 
56 /* Lockdep stuff.  */
57 static inline void
__mutex_init(struct mutex * mutex,const char * name __unused,struct lock_class_key * key __unused)58 __mutex_init(struct mutex *mutex, const char *name __unused,
59     struct lock_class_key *key __unused)
60 {
61 	linux_mutex_init(mutex);
62 }
63 
64 /* Another name collision.  */
65 static inline void
linux_mutex_destroy(struct mutex * mutex)66 linux_mutex_destroy(struct mutex *mutex)
67 {
68 	mutex_destroy(&mutex->mtx_lock);
69 }
70 
71 static inline void
mutex_lock(struct mutex * mutex)72 mutex_lock(struct mutex *mutex)
73 {
74 	mutex_enter(&mutex->mtx_lock);
75 }
76 
77 static inline int
mutex_lock_interruptible(struct mutex * mutex)78 mutex_lock_interruptible(struct mutex *mutex)
79 {
80 	mutex_enter(&mutex->mtx_lock); /* XXX */
81 	return 0;
82 }
83 
84 static inline int
mutex_trylock(struct mutex * mutex)85 mutex_trylock(struct mutex *mutex)
86 {
87 	return mutex_tryenter(&mutex->mtx_lock);
88 }
89 
90 static inline void
mutex_unlock(struct mutex * mutex)91 mutex_unlock(struct mutex *mutex)
92 {
93 	mutex_exit(&mutex->mtx_lock);
94 }
95 
96 static inline bool
mutex_is_locked(struct mutex * mutex)97 mutex_is_locked(struct mutex *mutex)
98 {
99 	return mutex_owned(&mutex->mtx_lock);
100 }
101 
102 static inline void
mutex_lock_nest_lock(struct mutex * mutex,struct mutex * already)103 mutex_lock_nest_lock(struct mutex *mutex, struct mutex *already)
104 {
105 
106 	KASSERT(mutex_is_locked(already));
107 	mutex_lock(mutex);
108 }
109 
110 #define	lockdep_assert_held(m)	do {} while (0)
111 
112 #define	SINGLE_DEPTH_NESTING	0
113 
114 static inline void
mutex_lock_nested(struct mutex * mutex,unsigned subclass __unused)115 mutex_lock_nested(struct mutex *mutex, unsigned subclass __unused)
116 {
117 	mutex_lock(mutex);
118 }
119 
120 #endif  /* _LINUX_MUTEX_H_ */
121