1 #ifndef _LINUX_FS_NOTIFY_H 2 #define _LINUX_FS_NOTIFY_H 3 4 /* 5 * include/linux/fsnotify.h - generic hooks for filesystem notification, to 6 * reduce in-source duplication from both dnotify and inotify. 7 * 8 * We don't compile any of this away in some complicated menagerie of ifdefs. 9 * Instead, we rely on the code inside to optimize away as needed. 10 * 11 * (C) Copyright 2005 Robert Love 12 */ 13 14 #include <linux/fsnotify_backend.h> 15 #include <linux/audit.h> 16 #include <linux/slab.h> 17 18 /* 19 * fsnotify_d_instantiate - instantiate a dentry for inode 20 * Called with dcache_lock held. 21 */ 22 static inline void fsnotify_d_instantiate(struct dentry *dentry, 23 struct inode *inode) 24 { 25 __fsnotify_d_instantiate(dentry, inode); 26 } 27 28 /* Notify this dentry's parent about a child's events. */ 29 static inline void fsnotify_parent(struct file *file, struct dentry *dentry, __u32 mask) 30 { 31 if (!dentry) 32 dentry = file->f_path.dentry; 33 34 __fsnotify_parent(file, dentry, mask); 35 } 36 37 /* simple call site for access decisions */ 38 static inline int fsnotify_perm(struct file *file, int mask) 39 { 40 struct inode *inode = file->f_path.dentry->d_inode; 41 __u32 fsnotify_mask = 0; 42 43 if (file->f_mode & FMODE_NONOTIFY) 44 return 0; 45 if (!(mask & (MAY_READ | MAY_OPEN))) 46 return 0; 47 if (mask & MAY_OPEN) 48 fsnotify_mask = FS_OPEN_PERM; 49 else if (mask & MAY_READ) 50 fsnotify_mask = FS_ACCESS_PERM; 51 else 52 BUG(); 53 54 return fsnotify(inode, fsnotify_mask, file, FSNOTIFY_EVENT_FILE, NULL, 0); 55 } 56 57 /* 58 * fsnotify_d_move - dentry has been moved 59 * Called with dcache_lock and dentry->d_lock held. 60 */ 61 static inline void fsnotify_d_move(struct dentry *dentry) 62 { 63 /* 64 * On move we need to update dentry->d_flags to indicate if the new parent 65 * cares about events from this dentry. 66 */ 67 __fsnotify_update_dcache_flags(dentry); 68 } 69 70 /* 71 * fsnotify_link_count - inode's link count changed 72 */ 73 static inline void fsnotify_link_count(struct inode *inode) 74 { 75 fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 76 } 77 78 /* 79 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir 80 */ 81 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, 82 const unsigned char *old_name, 83 int isdir, struct inode *target, struct dentry *moved) 84 { 85 struct inode *source = moved->d_inode; 86 u32 fs_cookie = fsnotify_get_cookie(); 87 __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM); 88 __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO); 89 const unsigned char *new_name = moved->d_name.name; 90 91 if (old_dir == new_dir) 92 old_dir_mask |= FS_DN_RENAME; 93 94 if (isdir) { 95 old_dir_mask |= FS_IN_ISDIR; 96 new_dir_mask |= FS_IN_ISDIR; 97 } 98 99 fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie); 100 fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie); 101 102 if (target) 103 fsnotify_link_count(target); 104 105 if (source) 106 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0); 107 audit_inode_child(moved, new_dir); 108 } 109 110 /* 111 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed 112 */ 113 static inline void fsnotify_inode_delete(struct inode *inode) 114 { 115 __fsnotify_inode_delete(inode); 116 } 117 118 /* 119 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed 120 */ 121 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt) 122 { 123 __fsnotify_vfsmount_delete(mnt); 124 } 125 126 /* 127 * fsnotify_nameremove - a filename was removed from a directory 128 */ 129 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir) 130 { 131 __u32 mask = FS_DELETE; 132 133 if (isdir) 134 mask |= FS_IN_ISDIR; 135 136 fsnotify_parent(NULL, dentry, mask); 137 } 138 139 /* 140 * fsnotify_inoderemove - an inode is going away 141 */ 142 static inline void fsnotify_inoderemove(struct inode *inode) 143 { 144 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 145 __fsnotify_inode_delete(inode); 146 } 147 148 /* 149 * fsnotify_create - 'name' was linked in 150 */ 151 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry) 152 { 153 audit_inode_child(dentry, inode); 154 155 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 156 } 157 158 /* 159 * fsnotify_link - new hardlink in 'inode' directory 160 * Note: We have to pass also the linked inode ptr as some filesystems leave 161 * new_dentry->d_inode NULL and instantiate inode pointer later 162 */ 163 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry) 164 { 165 fsnotify_link_count(inode); 166 audit_inode_child(new_dentry, dir); 167 168 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0); 169 } 170 171 /* 172 * fsnotify_mkdir - directory 'name' was created 173 */ 174 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) 175 { 176 __u32 mask = (FS_CREATE | FS_IN_ISDIR); 177 struct inode *d_inode = dentry->d_inode; 178 179 audit_inode_child(dentry, inode); 180 181 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 182 } 183 184 /* 185 * fsnotify_access - file was read 186 */ 187 static inline void fsnotify_access(struct file *file) 188 { 189 struct inode *inode = file->f_path.dentry->d_inode; 190 __u32 mask = FS_ACCESS; 191 192 if (S_ISDIR(inode->i_mode)) 193 mask |= FS_IN_ISDIR; 194 195 if (!(file->f_mode & FMODE_NONOTIFY)) { 196 fsnotify_parent(file, NULL, mask); 197 fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0); 198 } 199 } 200 201 /* 202 * fsnotify_modify - file was modified 203 */ 204 static inline void fsnotify_modify(struct file *file) 205 { 206 struct inode *inode = file->f_path.dentry->d_inode; 207 __u32 mask = FS_MODIFY; 208 209 if (S_ISDIR(inode->i_mode)) 210 mask |= FS_IN_ISDIR; 211 212 if (!(file->f_mode & FMODE_NONOTIFY)) { 213 fsnotify_parent(file, NULL, mask); 214 fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0); 215 } 216 } 217 218 /* 219 * fsnotify_open - file was opened 220 */ 221 static inline void fsnotify_open(struct file *file) 222 { 223 struct inode *inode = file->f_path.dentry->d_inode; 224 __u32 mask = FS_OPEN; 225 226 if (S_ISDIR(inode->i_mode)) 227 mask |= FS_IN_ISDIR; 228 229 if (!(file->f_mode & FMODE_NONOTIFY)) { 230 fsnotify_parent(file, NULL, mask); 231 fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0); 232 } 233 } 234 235 /* 236 * fsnotify_close - file was closed 237 */ 238 static inline void fsnotify_close(struct file *file) 239 { 240 struct inode *inode = file->f_path.dentry->d_inode; 241 fmode_t mode = file->f_mode; 242 __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE; 243 244 if (S_ISDIR(inode->i_mode)) 245 mask |= FS_IN_ISDIR; 246 247 if (!(file->f_mode & FMODE_NONOTIFY)) { 248 fsnotify_parent(file, NULL, mask); 249 fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0); 250 } 251 } 252 253 /* 254 * fsnotify_xattr - extended attributes were changed 255 */ 256 static inline void fsnotify_xattr(struct dentry *dentry) 257 { 258 struct inode *inode = dentry->d_inode; 259 __u32 mask = FS_ATTRIB; 260 261 if (S_ISDIR(inode->i_mode)) 262 mask |= FS_IN_ISDIR; 263 264 fsnotify_parent(NULL, dentry, mask); 265 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 266 } 267 268 /* 269 * fsnotify_change - notify_change event. file was modified and/or metadata 270 * was changed. 271 */ 272 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid) 273 { 274 struct inode *inode = dentry->d_inode; 275 __u32 mask = 0; 276 277 if (ia_valid & ATTR_UID) 278 mask |= FS_ATTRIB; 279 if (ia_valid & ATTR_GID) 280 mask |= FS_ATTRIB; 281 if (ia_valid & ATTR_SIZE) 282 mask |= FS_MODIFY; 283 284 /* both times implies a utime(s) call */ 285 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) 286 mask |= FS_ATTRIB; 287 else if (ia_valid & ATTR_ATIME) 288 mask |= FS_ACCESS; 289 else if (ia_valid & ATTR_MTIME) 290 mask |= FS_MODIFY; 291 292 if (ia_valid & ATTR_MODE) 293 mask |= FS_ATTRIB; 294 295 if (mask) { 296 if (S_ISDIR(inode->i_mode)) 297 mask |= FS_IN_ISDIR; 298 299 fsnotify_parent(NULL, dentry, mask); 300 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 301 } 302 } 303 304 #if defined(CONFIG_FSNOTIFY) /* notify helpers */ 305 306 /* 307 * fsnotify_oldname_init - save off the old filename before we change it 308 */ 309 static inline const unsigned char *fsnotify_oldname_init(const unsigned char *name) 310 { 311 return kstrdup(name, GFP_KERNEL); 312 } 313 314 /* 315 * fsnotify_oldname_free - free the name we got from fsnotify_oldname_init 316 */ 317 static inline void fsnotify_oldname_free(const unsigned char *old_name) 318 { 319 kfree(old_name); 320 } 321 322 #else /* CONFIG_FSNOTIFY */ 323 324 static inline const char *fsnotify_oldname_init(const unsigned char *name) 325 { 326 return NULL; 327 } 328 329 static inline void fsnotify_oldname_free(const unsigned char *old_name) 330 { 331 } 332 333 #endif /* CONFIG_FSNOTIFY */ 334 335 #endif /* _LINUX_FS_NOTIFY_H */ 336