xref: /linux/fs/tracefs/internal.h (revision eed4edda910fe34dfae8c6bfbcf57f4593a54295)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _TRACEFS_INTERNAL_H
3 #define _TRACEFS_INTERNAL_H
4 
5 enum {
6 	TRACEFS_EVENT_INODE		= BIT(1),
7 	TRACEFS_EVENT_TOP_INODE		= BIT(2),
8 	TRACEFS_GID_PERM_SET		= BIT(3),
9 	TRACEFS_UID_PERM_SET		= BIT(4),
10 	TRACEFS_INSTANCE_INODE		= BIT(5),
11 };
12 
13 struct tracefs_inode {
14 	struct inode            vfs_inode;
15 	/* The below gets initialized with memset_after(ti, 0, vfs_inode) */
16 	unsigned long           flags;
17 	void                    *private;
18 };
19 
20 /*
21  * struct eventfs_attr - cache the mode and ownership of a eventfs entry
22  * @mode:	saved mode plus flags of what is saved
23  * @uid:	saved uid if changed
24  * @gid:	saved gid if changed
25  */
26 struct eventfs_attr {
27 	int				mode;
28 	kuid_t				uid;
29 	kgid_t				gid;
30 };
31 
32 /*
33  * struct eventfs_inode - hold the properties of the eventfs directories.
34  * @list:	link list into the parent directory
35  * @rcu:	Union with @list for freeing
36  * @children:	link list into the child eventfs_inode
37  * @entries:	the array of entries representing the files in the directory
38  * @name:	the name of the directory to create
39  * @events_dir: the dentry of the events directory
40  * @entry_attrs: Saved mode and ownership of the @d_children
41  * @data:	The private data to pass to the callbacks
42  * @attr:	Saved mode and ownership of eventfs_inode itself
43  * @is_freed:	Flag set if the eventfs is on its way to be freed
44  *                Note if is_freed is set, then dentry is corrupted.
45  * @is_events:	Flag set for only the top level "events" directory
46  * @nr_entries: The number of items in @entries
47  * @ino:	The saved inode number
48  */
49 struct eventfs_inode {
50 	union {
51 		struct list_head	list;
52 		struct rcu_head		rcu;
53 	};
54 	struct list_head		children;
55 	const struct eventfs_entry	*entries;
56 	const char			*name;
57 	struct dentry			*events_dir;
58 	struct eventfs_attr		*entry_attrs;
59 	void				*data;
60 	struct eventfs_attr		attr;
61 	struct kref			kref;
62 	unsigned int			is_freed:1;
63 	unsigned int			is_events:1;
64 	unsigned int			nr_entries:30;
65 	unsigned int			ino;
66 };
67 
68 static inline struct tracefs_inode *get_tracefs(const struct inode *inode)
69 {
70 	return container_of(inode, struct tracefs_inode, vfs_inode);
71 }
72 
73 struct dentry *tracefs_start_creating(const char *name, struct dentry *parent);
74 struct dentry *tracefs_end_creating(struct dentry *dentry);
75 struct dentry *tracefs_failed_creating(struct dentry *dentry);
76 struct inode *tracefs_get_inode(struct super_block *sb);
77 
78 void eventfs_d_release(struct dentry *dentry);
79 
80 #endif /* _TRACEFS_INTERNAL_H */
81