xref: /netbsd-src/sys/external/bsd/drm2/include/linux/mutex.h (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /*	$NetBSD: mutex.h,v 1.12 2020/02/14 14:34:59 maya 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 #include <asm/processor.h>
40 
41 #include <linux/list.h>
42 
43 #define	__acquires(lock)			/* XXX lockdep stuff */
44 #define	__releases(lock)			/* XXX lockdep stuff */
45 #define might_lock(lock) do {} while(0) 	/* XXX lockdep stuff */
46 
47 struct mutex {
48 	kmutex_t mtx_lock;
49 };
50 
51 struct lock_class_key {
52 };
53 
54 /* Name collision.  Pooh.  */
55 static inline void
56 linux_mutex_init(struct mutex *mutex)
57 {
58 	mutex_init(&mutex->mtx_lock, MUTEX_DEFAULT, IPL_NONE);
59 }
60 
61 /* Lockdep stuff.  */
62 static inline void
63 __mutex_init(struct mutex *mutex, const char *name __unused,
64     struct lock_class_key *key __unused)
65 {
66 	linux_mutex_init(mutex);
67 }
68 
69 /* Another name collision.  */
70 static inline void
71 linux_mutex_destroy(struct mutex *mutex)
72 {
73 	mutex_destroy(&mutex->mtx_lock);
74 }
75 
76 static inline void
77 mutex_lock(struct mutex *mutex)
78 {
79 	mutex_enter(&mutex->mtx_lock);
80 }
81 
82 static inline int
83 mutex_lock_interruptible(struct mutex *mutex)
84 {
85 	mutex_enter(&mutex->mtx_lock); /* XXX */
86 	return 0;
87 }
88 
89 static inline int
90 mutex_trylock(struct mutex *mutex)
91 {
92 	return mutex_tryenter(&mutex->mtx_lock);
93 }
94 
95 static inline void
96 mutex_unlock(struct mutex *mutex)
97 {
98 	mutex_exit(&mutex->mtx_lock);
99 }
100 
101 static inline bool
102 mutex_is_locked(struct mutex *mutex)
103 {
104 	return mutex_owned(&mutex->mtx_lock);
105 }
106 
107 static inline void
108 mutex_lock_nest_lock(struct mutex *mutex, struct mutex *already)
109 {
110 
111 	KASSERT(mutex_is_locked(already));
112 	mutex_lock(mutex);
113 }
114 
115 #define	__lockdep_used		__unused
116 #define	lockdep_assert_held(m)	do {} while (0)
117 #define	lockdep_is_held(m)	1
118 
119 #define	SINGLE_DEPTH_NESTING	0
120 
121 static inline void
122 mutex_lock_nested(struct mutex *mutex, unsigned subclass __unused)
123 {
124 	mutex_lock(mutex);
125 }
126 
127 #endif  /* _LINUX_MUTEX_H_ */
128