1 /* 2 * Inode based directory notification for Linux 3 * 4 * Copyright (C) 2005 John McCutchan 5 */ 6 7 #ifndef _LINUX_INOTIFY_H 8 #define _LINUX_INOTIFY_H 9 10 #include <linux/types.h> 11 12 /* 13 * struct inotify_event - structure read from the inotify device for each event 14 * 15 * When you are watching a directory, you will receive the filename for events 16 * such as IN_CREATE, IN_DELETE, IN_OPEN, IN_CLOSE, ..., relative to the wd. 17 */ 18 struct inotify_event { 19 __s32 wd; /* watch descriptor */ 20 __u32 mask; /* watch mask */ 21 __u32 cookie; /* cookie to synchronize two events */ 22 __u32 len; /* length (including nulls) of name */ 23 char name[0]; /* stub for possible name */ 24 }; 25 26 /* the following are legal, implemented events that user-space can watch for */ 27 #define IN_ACCESS 0x00000001 /* File was accessed */ 28 #define IN_MODIFY 0x00000002 /* File was modified */ 29 #define IN_ATTRIB 0x00000004 /* Metadata changed */ 30 #define IN_CLOSE_WRITE 0x00000008 /* Writtable file was closed */ 31 #define IN_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */ 32 #define IN_OPEN 0x00000020 /* File was opened */ 33 #define IN_MOVED_FROM 0x00000040 /* File was moved from X */ 34 #define IN_MOVED_TO 0x00000080 /* File was moved to Y */ 35 #define IN_CREATE 0x00000100 /* Subfile was created */ 36 #define IN_DELETE 0x00000200 /* Subfile was deleted */ 37 #define IN_DELETE_SELF 0x00000400 /* Self was deleted */ 38 #define IN_MOVE_SELF 0x00000800 /* Self was moved */ 39 40 /* the following are legal events. they are sent as needed to any watch */ 41 #define IN_UNMOUNT 0x00002000 /* Backing fs was unmounted */ 42 #define IN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */ 43 #define IN_IGNORED 0x00008000 /* File was ignored */ 44 45 /* helper events */ 46 #define IN_CLOSE (IN_CLOSE_WRITE | IN_CLOSE_NOWRITE) /* close */ 47 #define IN_MOVE (IN_MOVED_FROM | IN_MOVED_TO) /* moves */ 48 49 /* special flags */ 50 #define IN_ONLYDIR 0x01000000 /* only watch the path if it is a directory */ 51 #define IN_DONT_FOLLOW 0x02000000 /* don't follow a sym link */ 52 #define IN_MASK_ADD 0x20000000 /* add to the mask of an already existing watch */ 53 #define IN_ISDIR 0x40000000 /* event occurred against dir */ 54 #define IN_ONESHOT 0x80000000 /* only send event once */ 55 56 /* 57 * All of the events - we build the list by hand so that we can add flags in 58 * the future and not break backward compatibility. Apps will get only the 59 * events that they originally wanted. Be sure to add new events here! 60 */ 61 #define IN_ALL_EVENTS (IN_ACCESS | IN_MODIFY | IN_ATTRIB | IN_CLOSE_WRITE | \ 62 IN_CLOSE_NOWRITE | IN_OPEN | IN_MOVED_FROM | \ 63 IN_MOVED_TO | IN_DELETE | IN_CREATE | IN_DELETE_SELF | \ 64 IN_MOVE_SELF) 65 66 #ifdef __KERNEL__ 67 68 #include <linux/dcache.h> 69 #include <linux/fs.h> 70 71 /* 72 * struct inotify_watch - represents a watch request on a specific inode 73 * 74 * h_list is protected by ih->mutex of the associated inotify_handle. 75 * i_list, mask are protected by inode->inotify_mutex of the associated inode. 76 * ih, inode, and wd are never written to once the watch is created. 77 * 78 * Callers must use the established inotify interfaces to access inotify_watch 79 * contents. The content of this structure is private to the inotify 80 * implementation. 81 */ 82 struct inotify_watch { 83 struct list_head h_list; /* entry in inotify_handle's list */ 84 struct list_head i_list; /* entry in inode's list */ 85 atomic_t count; /* reference count */ 86 struct inotify_handle *ih; /* associated inotify handle */ 87 struct inode *inode; /* associated inode */ 88 __s32 wd; /* watch descriptor */ 89 __u32 mask; /* event mask for this watch */ 90 }; 91 92 struct inotify_operations { 93 void (*handle_event)(struct inotify_watch *, u32, u32, u32, 94 const char *, struct inode *); 95 void (*destroy_watch)(struct inotify_watch *); 96 }; 97 98 #ifdef CONFIG_INOTIFY 99 100 /* Kernel API for producing events */ 101 102 extern void inotify_d_instantiate(struct dentry *, struct inode *); 103 extern void inotify_d_move(struct dentry *); 104 extern void inotify_inode_queue_event(struct inode *, __u32, __u32, 105 const char *, struct inode *); 106 extern void inotify_dentry_parent_queue_event(struct dentry *, __u32, __u32, 107 const char *); 108 extern void inotify_unmount_inodes(struct list_head *); 109 extern void inotify_inode_is_dead(struct inode *); 110 extern u32 inotify_get_cookie(void); 111 112 /* Kernel Consumer API */ 113 114 extern struct inotify_handle *inotify_init(const struct inotify_operations *); 115 extern void inotify_init_watch(struct inotify_watch *); 116 extern void inotify_destroy(struct inotify_handle *); 117 extern __s32 inotify_find_watch(struct inotify_handle *, struct inode *, 118 struct inotify_watch **); 119 extern __s32 inotify_find_update_watch(struct inotify_handle *, struct inode *, 120 u32); 121 extern __s32 inotify_add_watch(struct inotify_handle *, struct inotify_watch *, 122 struct inode *, __u32); 123 extern int inotify_rm_watch(struct inotify_handle *, struct inotify_watch *); 124 extern int inotify_rm_wd(struct inotify_handle *, __u32); 125 extern void inotify_remove_watch_locked(struct inotify_handle *, 126 struct inotify_watch *); 127 extern void get_inotify_watch(struct inotify_watch *); 128 extern void put_inotify_watch(struct inotify_watch *); 129 130 #else 131 132 static inline void inotify_d_instantiate(struct dentry *dentry, 133 struct inode *inode) 134 { 135 } 136 137 static inline void inotify_d_move(struct dentry *dentry) 138 { 139 } 140 141 static inline void inotify_inode_queue_event(struct inode *inode, 142 __u32 mask, __u32 cookie, 143 const char *filename, 144 struct inode *n_inode) 145 { 146 } 147 148 static inline void inotify_dentry_parent_queue_event(struct dentry *dentry, 149 __u32 mask, __u32 cookie, 150 const char *filename) 151 { 152 } 153 154 static inline void inotify_unmount_inodes(struct list_head *list) 155 { 156 } 157 158 static inline void inotify_inode_is_dead(struct inode *inode) 159 { 160 } 161 162 static inline u32 inotify_get_cookie(void) 163 { 164 return 0; 165 } 166 167 static inline struct inotify_handle *inotify_init(const struct inotify_operations *ops) 168 { 169 return ERR_PTR(-EOPNOTSUPP); 170 } 171 172 static inline void inotify_init_watch(struct inotify_watch *watch) 173 { 174 } 175 176 static inline void inotify_destroy(struct inotify_handle *ih) 177 { 178 } 179 180 static inline __s32 inotify_find_watch(struct inotify_handle *ih, struct inode *inode, 181 struct inotify_watch **watchp) 182 { 183 return -EOPNOTSUPP; 184 } 185 186 static inline __s32 inotify_find_update_watch(struct inotify_handle *ih, 187 struct inode *inode, u32 mask) 188 { 189 return -EOPNOTSUPP; 190 } 191 192 static inline __s32 inotify_add_watch(struct inotify_handle *ih, 193 struct inotify_watch *watch, 194 struct inode *inode, __u32 mask) 195 { 196 return -EOPNOTSUPP; 197 } 198 199 static inline int inotify_rm_watch(struct inotify_handle *ih, 200 struct inotify_watch *watch) 201 { 202 return -EOPNOTSUPP; 203 } 204 205 static inline int inotify_rm_wd(struct inotify_handle *ih, __u32 wd) 206 { 207 return -EOPNOTSUPP; 208 } 209 210 static inline void inotify_remove_watch_locked(struct inotify_handle *ih, 211 struct inotify_watch *watch) 212 { 213 } 214 215 static inline void get_inotify_watch(struct inotify_watch *watch) 216 { 217 } 218 219 static inline void put_inotify_watch(struct inotify_watch *watch) 220 { 221 } 222 223 #endif /* CONFIG_INOTIFY */ 224 225 #endif /* __KERNEL __ */ 226 227 #endif /* _LINUX_INOTIFY_H */ 228
