nlm: Ensure callback code also checks that the files match
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / include / linux / rwsem-spinlock.h
CommitLineData
1da177e4
LT
1/* rwsem-spinlock.h: fallback C implementation
2 *
3 * Copyright (c) 2001 David Howells (dhowells@redhat.com).
4 * - Derived partially from ideas by Andrea Arcangeli <andrea@suse.de>
5 * - Derived also from comments by Linus
6 */
7
8#ifndef _LINUX_RWSEM_SPINLOCK_H
9#define _LINUX_RWSEM_SPINLOCK_H
10
11#ifndef _LINUX_RWSEM_H
12#error "please don't include linux/rwsem-spinlock.h directly, use linux/rwsem.h instead"
13#endif
14
1da177e4 15#ifdef __KERNEL__
1da177e4
LT
16/*
17 * the rw-semaphore definition
18 * - if activity is 0 then there are no active readers or writers
19 * - if activity is +ve then that is the number of active readers
20 * - if activity is -1 then there is one active writer
21 * - if wait_list is not empty, then there are processes waiting for the semaphore
22 */
23struct rw_semaphore {
24 __s32 activity;
ddb6c9b5 25 raw_spinlock_t wait_lock;
1da177e4 26 struct list_head wait_list;
4ea2176d
IM
27#ifdef CONFIG_DEBUG_LOCK_ALLOC
28 struct lockdep_map dep_map;
29#endif
1da177e4
LT
30};
31
12249b34 32#define RWSEM_UNLOCKED_VALUE 0x00000000
4ea2176d 33
b3c97528
HH
34extern void __down_read(struct rw_semaphore *sem);
35extern int __down_read_trylock(struct rw_semaphore *sem);
36extern void __down_write(struct rw_semaphore *sem);
37extern void __down_write_nested(struct rw_semaphore *sem, int subclass);
38extern int __down_write_trylock(struct rw_semaphore *sem);
39extern void __up_read(struct rw_semaphore *sem);
40extern void __up_write(struct rw_semaphore *sem);
41extern void __downgrade_write(struct rw_semaphore *sem);
29671f22 42extern int rwsem_is_locked(struct rw_semaphore *sem);
eb92f4ef 43
1da177e4
LT
44#endif /* __KERNEL__ */
45#endif /* _LINUX_RWSEM_SPINLOCK_H */