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1 /*
2 * Copyright (C) 2008 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18 #include <linux/sched.h>
19 #include <linux/gfp.h>
20 #include <linux/pagemap.h>
21 #include <linux/spinlock.h>
22 #include <linux/page-flags.h>
23 #include <linux/bug.h>
24 #include "ctree.h"
25 #include "extent_io.h"
26 #include "locking.h"
27
28 int btrfs_tree_lock(struct extent_buffer *eb)
29 {
30 lock_page(eb->first_page);
31 return 0;
32 }
33
34 int btrfs_try_tree_lock(struct extent_buffer *eb)
35 {
36 return TestSetPageLocked(eb->first_page);
37 }
38
39 int btrfs_tree_unlock(struct extent_buffer *eb)
40 {
41 WARN_ON(!PageLocked(eb->first_page));
42 unlock_page(eb->first_page);
43 return 0;
44 }
45
46 int btrfs_tree_locked(struct extent_buffer *eb)
47 {
48 return PageLocked(eb->first_page);
49 }
50