xref: /netbsd-src/sys/external/bsd/drm2/include/linux/mutex.h (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /*	$NetBSD: mutex.h,v 1.11 2018/08/27 07:34:03 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 #include <linux/list.h>
39 
40 #define	__acquires(lock)			/* XXX lockdep stuff */
41 #define	__releases(lock)			/* XXX lockdep stuff */
42 #define might_lock(lock) do {} while(0) 	/* XXX lockdep stuff */
43 
44 struct mutex {
45 	kmutex_t mtx_lock;
46 };
47 
48 struct lock_class_key {
49 };
50 
51 /* Name collision.  Pooh.  */
52 static inline void
53 linux_mutex_init(struct mutex *mutex)
54 {
55 	mutex_init(&mutex->mtx_lock, MUTEX_DEFAULT, IPL_NONE);
56 }
57 
58 /* Lockdep stuff.  */
59 static inline void
60 __mutex_init(struct mutex *mutex, const char *name __unused,
61     struct lock_class_key *key __unused)
62 {
63 	linux_mutex_init(mutex);
64 }
65 
66 /* Another name collision.  */
67 static inline void
68 linux_mutex_destroy(struct mutex *mutex)
69 {
70 	mutex_destroy(&mutex->mtx_lock);
71 }
72 
73 static inline void
74 mutex_lock(struct mutex *mutex)
75 {
76 	mutex_enter(&mutex->mtx_lock);
77 }
78 
79 static inline int
80 mutex_lock_interruptible(struct mutex *mutex)
81 {
82 	mutex_enter(&mutex->mtx_lock); /* XXX */
83 	return 0;
84 }
85 
86 static inline int
87 mutex_trylock(struct mutex *mutex)
88 {
89 	return mutex_tryenter(&mutex->mtx_lock);
90 }
91 
92 static inline void
93 mutex_unlock(struct mutex *mutex)
94 {
95 	mutex_exit(&mutex->mtx_lock);
96 }
97 
98 static inline bool
99 mutex_is_locked(struct mutex *mutex)
100 {
101 	return mutex_owned(&mutex->mtx_lock);
102 }
103 
104 static inline void
105 mutex_lock_nest_lock(struct mutex *mutex, struct mutex *already)
106 {
107 
108 	KASSERT(mutex_is_locked(already));
109 	mutex_lock(mutex);
110 }
111 
112 #define	__lockdep_used		__unused
113 #define	lockdep_assert_held(m)	do {} while (0)
114 #define	lockdep_is_held(m)	1
115 
116 #define	SINGLE_DEPTH_NESTING	0
117 
118 static inline void
119 mutex_lock_nested(struct mutex *mutex, unsigned subclass __unused)
120 {
121 	mutex_lock(mutex);
122 }
123 
124 #endif  /* _LINUX_MUTEX_H_ */
125