xref: /linux/fs/btrfs/locking.h (revision e15d5a53ea3239e537d3a0c4bdfce8a4ea4e0da6)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2008 Oracle.  All rights reserved.
4  */
5 
6 #ifndef BTRFS_LOCKING_H
7 #define BTRFS_LOCKING_H
8 
9 #define BTRFS_WRITE_LOCK 1
10 #define BTRFS_READ_LOCK 2
11 #define BTRFS_WRITE_LOCK_BLOCKING 3
12 #define BTRFS_READ_LOCK_BLOCKING 4
13 
14 void btrfs_tree_lock(struct extent_buffer *eb);
15 void btrfs_tree_unlock(struct extent_buffer *eb);
16 
17 void btrfs_tree_read_lock(struct extent_buffer *eb);
18 void btrfs_tree_read_unlock(struct extent_buffer *eb);
19 void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb);
20 void btrfs_set_lock_blocking_read(struct extent_buffer *eb);
21 void btrfs_set_lock_blocking_write(struct extent_buffer *eb);
22 void btrfs_clear_lock_blocking_read(struct extent_buffer *eb);
23 void btrfs_clear_lock_blocking_write(struct extent_buffer *eb);
24 void btrfs_assert_tree_locked(struct extent_buffer *eb);
25 int btrfs_try_tree_read_lock(struct extent_buffer *eb);
26 int btrfs_try_tree_write_lock(struct extent_buffer *eb);
27 int btrfs_tree_read_lock_atomic(struct extent_buffer *eb);
28 
29 
30 static inline void btrfs_tree_unlock_rw(struct extent_buffer *eb, int rw)
31 {
32 	if (rw == BTRFS_WRITE_LOCK || rw == BTRFS_WRITE_LOCK_BLOCKING)
33 		btrfs_tree_unlock(eb);
34 	else if (rw == BTRFS_READ_LOCK_BLOCKING)
35 		btrfs_tree_read_unlock_blocking(eb);
36 	else if (rw == BTRFS_READ_LOCK)
37 		btrfs_tree_read_unlock(eb);
38 	else
39 		BUG();
40 }
41 
42 #endif
43