1 /*-
2 * Copyright (c) 2017 Mellanox Technologies, Ltd.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice unmodified, this list of conditions, and the following
10 * disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28 #ifndef _LINUXKPI_LINUX_WW_MUTEX_H_
29 #define _LINUXKPI_LINUX_WW_MUTEX_H_
30
31 #include <sys/param.h>
32 #include <sys/proc.h>
33 #include <sys/condvar.h>
34 #include <sys/kernel.h>
35
36 #include <linux/mutex.h>
37
38 struct ww_class {
39 const char *mutex_name;
40 };
41
42 struct ww_acquire_ctx {
43 };
44
45 struct ww_mutex {
46 struct mutex base;
47 struct cv condvar;
48 struct ww_acquire_ctx *ctx;
49 };
50
51 #define DEFINE_WW_CLASS(name) \
52 struct ww_class name = { \
53 .mutex_name = mutex_name(#name "_mutex") \
54 }
55
56 #define DEFINE_WW_MUTEX(name, ww_class) \
57 struct ww_mutex name; \
58 static void name##_init(void *arg) \
59 { \
60 ww_mutex_init(&name, &ww_class); \
61 } \
62 SYSINIT(name, SI_SUB_LOCK, SI_ORDER_SECOND, name##_init, NULL)
63
64 #define DEFINE_WD_CLASS(name) DEFINE_WW_CLASS(name)
65
66 #define ww_mutex_is_locked(_m) \
67 sx_xlocked(&(_m)->base.sx)
68
69 #define ww_mutex_lock_slow(_m, _x) \
70 ww_mutex_lock(_m, _x)
71
72 #define ww_mutex_lock_slow_interruptible(_m, _x) \
73 ww_mutex_lock_interruptible(_m, _x)
74
75 static inline int __must_check
76 ww_mutex_trylock(struct ww_mutex *lock)
77 {
78 return (mutex_trylock(&lock->base));
79 }
80
81 extern int linux_ww_mutex_lock_sub(struct ww_mutex *,
82 struct ww_acquire_ctx *, int catch_signal);
83
84 static inline int
85 ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
86 {
87 if (MUTEX_SKIP())
88 return (0);
89 else if ((struct thread *)SX_OWNER(lock->base.sx.sx_lock) == curthread)
90 return (-EALREADY);
91 else
92 return (linux_ww_mutex_lock_sub(lock, ctx, 0));
93 }
94
95 static inline int
96 ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
97 {
98 if (MUTEX_SKIP())
99 return (0);
100 else if ((struct thread *)SX_OWNER(lock->base.sx.sx_lock) == curthread)
101 return (-EALREADY);
102 else
103 return (linux_ww_mutex_lock_sub(lock, ctx, 1));
104 }
105
106 extern void linux_ww_mutex_unlock_sub(struct ww_mutex *);
107
108 static inline void
109 ww_mutex_unlock(struct ww_mutex *lock)
110 {
111 if (MUTEX_SKIP())
112 return;
113 else
114 linux_ww_mutex_unlock_sub(lock);
115 }
116
117 static inline void
118 ww_mutex_destroy(struct ww_mutex *lock)
119 {
120 cv_destroy(&lock->condvar);
121 mutex_destroy(&lock->base);
122 }
123
124 static inline void
125 ww_acquire_init(struct ww_acquire_ctx *ctx, struct ww_class *ww_class)
126 {
127 }
128
129 static inline void
130 ww_mutex_init(struct ww_mutex *lock, struct ww_class *ww_class)
131 {
132 linux_mutex_init(&lock->base, ww_class->mutex_name, SX_NOWITNESS);
133 cv_init(&lock->condvar, "lkpi-ww");
134 }
135
136 static inline void
137 ww_acquire_fini(struct ww_acquire_ctx *ctx)
138 {
139 }
140
141 static inline void
142 ww_acquire_done(struct ww_acquire_ctx *ctx)
143 {
144 }
145
146 #endif /* _LINUXKPI_LINUX_WW_MUTEX_H_ */
Cache object: d0ab2217696f4f6089f25b77dbb31fad
|