Linux 2.6.33-rc2
[pohmelfs.git] / include / linux / inotify.h
blob37ea2894b3c0ff870a79f014fb370894b3709e44
1 /*
2 * Inode based directory notification for Linux
4 * Copyright (C) 2005 John McCutchan
5 */
7 #ifndef _LINUX_INOTIFY_H
8 #define _LINUX_INOTIFY_H
10 /* For O_CLOEXEC and O_NONBLOCK */
11 #include <linux/fcntl.h>
12 #include <linux/types.h>
15 * struct inotify_event - structure read from the inotify device for each event
17 * When you are watching a directory, you will receive the filename for events
18 * such as IN_CREATE, IN_DELETE, IN_OPEN, IN_CLOSE, ..., relative to the wd.
20 struct inotify_event {
21 __s32 wd; /* watch descriptor */
22 __u32 mask; /* watch mask */
23 __u32 cookie; /* cookie to synchronize two events */
24 __u32 len; /* length (including nulls) of name */
25 char name[0]; /* stub for possible name */
28 /* the following are legal, implemented events that user-space can watch for */
29 #define IN_ACCESS 0x00000001 /* File was accessed */
30 #define IN_MODIFY 0x00000002 /* File was modified */
31 #define IN_ATTRIB 0x00000004 /* Metadata changed */
32 #define IN_CLOSE_WRITE 0x00000008 /* Writtable file was closed */
33 #define IN_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */
34 #define IN_OPEN 0x00000020 /* File was opened */
35 #define IN_MOVED_FROM 0x00000040 /* File was moved from X */
36 #define IN_MOVED_TO 0x00000080 /* File was moved to Y */
37 #define IN_CREATE 0x00000100 /* Subfile was created */
38 #define IN_DELETE 0x00000200 /* Subfile was deleted */
39 #define IN_DELETE_SELF 0x00000400 /* Self was deleted */
40 #define IN_MOVE_SELF 0x00000800 /* Self was moved */
42 /* the following are legal events. they are sent as needed to any watch */
43 #define IN_UNMOUNT 0x00002000 /* Backing fs was unmounted */
44 #define IN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */
45 #define IN_IGNORED 0x00008000 /* File was ignored */
47 /* helper events */
48 #define IN_CLOSE (IN_CLOSE_WRITE | IN_CLOSE_NOWRITE) /* close */
49 #define IN_MOVE (IN_MOVED_FROM | IN_MOVED_TO) /* moves */
51 /* special flags */
52 #define IN_ONLYDIR 0x01000000 /* only watch the path if it is a directory */
53 #define IN_DONT_FOLLOW 0x02000000 /* don't follow a sym link */
54 #define IN_MASK_ADD 0x20000000 /* add to the mask of an already existing watch */
55 #define IN_ISDIR 0x40000000 /* event occurred against dir */
56 #define IN_ONESHOT 0x80000000 /* only send event once */
59 * All of the events - we build the list by hand so that we can add flags in
60 * the future and not break backward compatibility. Apps will get only the
61 * events that they originally wanted. Be sure to add new events here!
63 #define IN_ALL_EVENTS (IN_ACCESS | IN_MODIFY | IN_ATTRIB | IN_CLOSE_WRITE | \
64 IN_CLOSE_NOWRITE | IN_OPEN | IN_MOVED_FROM | \
65 IN_MOVED_TO | IN_DELETE | IN_CREATE | IN_DELETE_SELF | \
66 IN_MOVE_SELF)
68 /* Flags for sys_inotify_init1. */
69 #define IN_CLOEXEC O_CLOEXEC
70 #define IN_NONBLOCK O_NONBLOCK
72 #ifdef __KERNEL__
74 #include <linux/dcache.h>
75 #include <linux/fs.h>
78 * struct inotify_watch - represents a watch request on a specific inode
80 * h_list is protected by ih->mutex of the associated inotify_handle.
81 * i_list, mask are protected by inode->inotify_mutex of the associated inode.
82 * ih, inode, and wd are never written to once the watch is created.
84 * Callers must use the established inotify interfaces to access inotify_watch
85 * contents. The content of this structure is private to the inotify
86 * implementation.
88 struct inotify_watch {
89 struct list_head h_list; /* entry in inotify_handle's list */
90 struct list_head i_list; /* entry in inode's list */
91 atomic_t count; /* reference count */
92 struct inotify_handle *ih; /* associated inotify handle */
93 struct inode *inode; /* associated inode */
94 __s32 wd; /* watch descriptor */
95 __u32 mask; /* event mask for this watch */
98 struct inotify_operations {
99 void (*handle_event)(struct inotify_watch *, u32, u32, u32,
100 const char *, struct inode *);
101 void (*destroy_watch)(struct inotify_watch *);
104 #ifdef CONFIG_INOTIFY
106 /* Kernel API for producing events */
108 extern void inotify_d_instantiate(struct dentry *, struct inode *);
109 extern void inotify_d_move(struct dentry *);
110 extern void inotify_inode_queue_event(struct inode *, __u32, __u32,
111 const char *, struct inode *);
112 extern void inotify_dentry_parent_queue_event(struct dentry *, __u32, __u32,
113 const char *);
114 extern void inotify_unmount_inodes(struct list_head *);
115 extern void inotify_inode_is_dead(struct inode *);
116 extern u32 inotify_get_cookie(void);
118 /* Kernel Consumer API */
120 extern struct inotify_handle *inotify_init(const struct inotify_operations *);
121 extern void inotify_init_watch(struct inotify_watch *);
122 extern void inotify_destroy(struct inotify_handle *);
123 extern __s32 inotify_find_watch(struct inotify_handle *, struct inode *,
124 struct inotify_watch **);
125 extern __s32 inotify_find_update_watch(struct inotify_handle *, struct inode *,
126 u32);
127 extern __s32 inotify_add_watch(struct inotify_handle *, struct inotify_watch *,
128 struct inode *, __u32);
129 extern __s32 inotify_clone_watch(struct inotify_watch *, struct inotify_watch *);
130 extern void inotify_evict_watch(struct inotify_watch *);
131 extern int inotify_rm_watch(struct inotify_handle *, struct inotify_watch *);
132 extern int inotify_rm_wd(struct inotify_handle *, __u32);
133 extern void inotify_remove_watch_locked(struct inotify_handle *,
134 struct inotify_watch *);
135 extern void get_inotify_watch(struct inotify_watch *);
136 extern void put_inotify_watch(struct inotify_watch *);
137 extern int pin_inotify_watch(struct inotify_watch *);
138 extern void unpin_inotify_watch(struct inotify_watch *);
140 #else
142 static inline void inotify_d_instantiate(struct dentry *dentry,
143 struct inode *inode)
147 static inline void inotify_d_move(struct dentry *dentry)
151 static inline void inotify_inode_queue_event(struct inode *inode,
152 __u32 mask, __u32 cookie,
153 const char *filename,
154 struct inode *n_inode)
158 static inline void inotify_dentry_parent_queue_event(struct dentry *dentry,
159 __u32 mask, __u32 cookie,
160 const char *filename)
164 static inline void inotify_unmount_inodes(struct list_head *list)
168 static inline void inotify_inode_is_dead(struct inode *inode)
172 static inline u32 inotify_get_cookie(void)
174 return 0;
177 static inline struct inotify_handle *inotify_init(const struct inotify_operations *ops)
179 return ERR_PTR(-EOPNOTSUPP);
182 static inline void inotify_init_watch(struct inotify_watch *watch)
186 static inline void inotify_destroy(struct inotify_handle *ih)
190 static inline __s32 inotify_find_watch(struct inotify_handle *ih, struct inode *inode,
191 struct inotify_watch **watchp)
193 return -EOPNOTSUPP;
196 static inline __s32 inotify_find_update_watch(struct inotify_handle *ih,
197 struct inode *inode, u32 mask)
199 return -EOPNOTSUPP;
202 static inline __s32 inotify_add_watch(struct inotify_handle *ih,
203 struct inotify_watch *watch,
204 struct inode *inode, __u32 mask)
206 return -EOPNOTSUPP;
209 static inline int inotify_rm_watch(struct inotify_handle *ih,
210 struct inotify_watch *watch)
212 return -EOPNOTSUPP;
215 static inline int inotify_rm_wd(struct inotify_handle *ih, __u32 wd)
217 return -EOPNOTSUPP;
220 static inline void inotify_remove_watch_locked(struct inotify_handle *ih,
221 struct inotify_watch *watch)
225 static inline void get_inotify_watch(struct inotify_watch *watch)
229 static inline void put_inotify_watch(struct inotify_watch *watch)
233 extern inline int pin_inotify_watch(struct inotify_watch *watch)
235 return 0;
238 extern inline void unpin_inotify_watch(struct inotify_watch *watch)
242 #endif /* CONFIG_INOTIFY */
244 #endif /* __KERNEL __ */
246 #endif /* _LINUX_INOTIFY_H */