1 #ifndef __LINUX_RWLOCK_TYPES_H
2 #define __LINUX_RWLOCK_TYPES_H
3 
4 /*
5  * include/linux/rwlock_types.h - generic rwlock type definitions
6  *				  and initializers
7  *
8  * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
9  * Released under the General Public License (GPL).
10  */
11 typedef struct {
12 	arch_rwlock_t raw_lock;
13 #ifdef CONFIG_GENERIC_LOCKBREAK
14 	unsigned int break_lock;
15 #endif
16 #ifdef CONFIG_DEBUG_SPINLOCK
17 	unsigned int magic, owner_cpu;
18 	void *owner;
19 #endif
20 #ifdef CONFIG_DEBUG_LOCK_ALLOC
21 	struct lockdep_map dep_map;
22 #endif
23 } rwlock_t;
24 
25 #define RWLOCK_MAGIC		0xdeaf1eed
26 
27 #ifdef CONFIG_DEBUG_LOCK_ALLOC
28 # define RW_DEP_MAP_INIT(lockname)	.dep_map = { .name = #lockname }
29 #else
30 # define RW_DEP_MAP_INIT(lockname)
31 #endif
32 
33 #ifdef CONFIG_DEBUG_SPINLOCK
34 #define __RW_LOCK_UNLOCKED(lockname)					\
35 	(rwlock_t)	{	.raw_lock = __ARCH_RW_LOCK_UNLOCKED,	\
36 				.magic = RWLOCK_MAGIC,			\
37 				.owner = SPINLOCK_OWNER_INIT,		\
38 				.owner_cpu = -1,			\
39 				RW_DEP_MAP_INIT(lockname) }
40 #else
41 #define __RW_LOCK_UNLOCKED(lockname) \
42 	(rwlock_t)	{	.raw_lock = __ARCH_RW_LOCK_UNLOCKED,	\
43 				RW_DEP_MAP_INIT(lockname) }
44 #endif
45 
46 #define DEFINE_RWLOCK(x)	rwlock_t x = __RW_LOCK_UNLOCKED(x)
47 
48 #endif /* __LINUX_RWLOCK_TYPES_H */
49