xref: /openbsd-src/sys/dev/pci/drm/include/linux/mutex.h (revision a0747c9f67a4ae71ccb71e62a28d1ea19e06a63c)
1 /* Public domain. */
2 
3 #ifndef _LINUX_MUTEX_H
4 #define _LINUX_MUTEX_H
5 
6 #include <sys/stdint.h>
7 #include <sys/rwlock.h>
8 #include <linux/list.h>
9 #include <linux/spinlock_types.h>
10 
11 #define DEFINE_MUTEX(x)		struct rwlock x = RWLOCK_INITIALIZER(#x)
12 
13 #define mutex_lock_interruptible_nested(rwl, subc) \
14 					mutex_lock_interruptible(rwl)
15 #define mutex_lock(rwl)			rw_enter_write(rwl)
16 #define mutex_lock_nest_lock(rwl, sub)	rw_enter_write(rwl)
17 #define mutex_lock_nested(rwl, sub)	rw_enter_write(rwl)
18 #define mutex_trylock(rwl)		(rw_enter(rwl, RW_WRITE | RW_NOSLEEP) == 0)
19 #define mutex_unlock(rwl)		rw_exit_write(rwl)
20 #define mutex_is_locked(rwl)		(rw_status(rwl) != 0)
21 #define mutex_destroy(rwl)
22 
23 static inline int
24 mutex_lock_interruptible(struct rwlock *rwl)
25 {
26 	if (rw_enter(rwl, RW_WRITE | RW_INTR) != 0)
27 		return -EINTR;
28 	return 0;
29 }
30 
31 enum mutex_trylock_recursive_result {
32 	MUTEX_TRYLOCK_FAILED,
33 	MUTEX_TRYLOCK_SUCCESS,
34 	MUTEX_TRYLOCK_RECURSIVE
35 };
36 
37 static inline enum mutex_trylock_recursive_result
38 mutex_trylock_recursive(struct rwlock *rwl)
39 {
40 	if (rw_status(rwl) == RW_WRITE)
41 		return MUTEX_TRYLOCK_RECURSIVE;
42 	if (mutex_trylock(rwl))
43 		return MUTEX_TRYLOCK_SUCCESS;
44 	return MUTEX_TRYLOCK_FAILED;
45 }
46 
47 int atomic_dec_and_mutex_lock(volatile int *, struct rwlock *);
48 
49 #endif
50