1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  internal.h - declarations internal to debugfs
4  *
5  *  Copyright (C) 2016 Nicolai Stange <nicstange@gmail.com>
6  */
7 
8 #ifndef _DEBUGFS_INTERNAL_H_
9 #define _DEBUGFS_INTERNAL_H_
10 
11 struct file_operations;
12 
13 /* declared over in file.c */
14 extern const struct file_operations debugfs_noop_file_operations;
15 extern const struct file_operations debugfs_open_proxy_file_operations;
16 extern const struct file_operations debugfs_full_proxy_file_operations;
17 
18 struct debugfs_fsdata {
19 	const struct file_operations *real_fops;
20 	refcount_t active_users;
21 	struct completion active_users_drained;
22 };
23 
24 /*
25  * A dentry's ->d_fsdata either points to the real fops or to a
26  * dynamically allocated debugfs_fsdata instance.
27  * In order to distinguish between these two cases, a real fops
28  * pointer gets its lowest bit set.
29  */
30 #define DEBUGFS_FSDATA_IS_REAL_FOPS_BIT BIT(0)
31 
32 /* Access BITS */
33 #define DEBUGFS_ALLOW_API	BIT(0)
34 #define DEBUGFS_ALLOW_MOUNT	BIT(1)
35 
36 #ifdef CONFIG_DEBUG_FS_ALLOW_ALL
37 #define DEFAULT_DEBUGFS_ALLOW_BITS (DEBUGFS_ALLOW_MOUNT | DEBUGFS_ALLOW_API)
38 #endif
39 #ifdef CONFIG_DEBUG_FS_DISALLOW_MOUNT
40 #define DEFAULT_DEBUGFS_ALLOW_BITS (DEBUGFS_ALLOW_API)
41 #endif
42 #ifdef CONFIG_DEBUG_FS_ALLOW_NONE
43 #define DEFAULT_DEBUGFS_ALLOW_BITS (0)
44 #endif
45 
46 #endif /* _DEBUGFS_INTERNAL_H_ */
47