xref: /openbmc/linux/fs/tracefs/internal.h (revision d5a9588c)
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_GID_PERM_SET		= BIT(2),
8 	TRACEFS_UID_PERM_SET		= BIT(3),
9 	TRACEFS_INSTANCE_INODE		= BIT(4),
10 };
11 
12 struct tracefs_inode {
13 	struct inode            vfs_inode;
14 	/* The below gets initialized with memset_after(ti, 0, vfs_inode) */
15 	struct list_head	list;
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  * @entry_attrs: Saved mode and ownership of the @d_children
40  * @data:	The private data to pass to the callbacks
41  * @attr:	Saved mode and ownership of eventfs_inode itself
42  * @is_freed:	Flag set if the eventfs is on its way to be freed
43  *                Note if is_freed is set, then dentry is corrupted.
44  * @is_events:	Flag set for only the top level "events" directory
45  * @nr_entries: The number of items in @entries
46  * @ino:	The saved inode number
47  */
48 struct eventfs_inode {
49 	union {
50 		struct list_head	list;
51 		struct rcu_head		rcu;
52 	};
53 	struct list_head		children;
54 	const struct eventfs_entry	*entries;
55 	const char			*name;
56 	struct eventfs_attr		*entry_attrs;
57 	void				*data;
58 	struct eventfs_attr		attr;
59 	struct kref			kref;
60 	unsigned int			is_freed:1;
61 	unsigned int			is_events:1;
62 	unsigned int			nr_entries:30;
63 	unsigned int			ino;
64 };
65 
66 static inline struct tracefs_inode *get_tracefs(const struct inode *inode)
67 {
68 	return container_of(inode, struct tracefs_inode, vfs_inode);
69 }
70 
71 struct dentry *tracefs_start_creating(const char *name, struct dentry *parent);
72 struct dentry *tracefs_end_creating(struct dentry *dentry);
73 struct dentry *tracefs_failed_creating(struct dentry *dentry);
74 struct inode *tracefs_get_inode(struct super_block *sb);
75 
76 void eventfs_remount(struct tracefs_inode *ti, bool update_uid, bool update_gid);
77 void eventfs_d_release(struct dentry *dentry);
78 
79 #endif /* _TRACEFS_INTERNAL_H */
80