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 path *path, struct dentry *dentry, __u32 mask) 30 { 31 if (!dentry) 32 dentry = path->dentry; 33 34 __fsnotify_parent(path, 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 path *path = &file->f_path; 41 struct inode *inode = path->dentry->d_inode; 42 __u32 fsnotify_mask = 0; 43 44 if (file->f_mode & FMODE_NONOTIFY) 45 return 0; 46 if (!(mask & (MAY_READ | MAY_OPEN))) 47 return 0; 48 if (mask & MAY_OPEN) 49 fsnotify_mask = FS_OPEN_PERM; 50 else if (mask & MAY_READ) 51 fsnotify_mask = FS_ACCESS_PERM; 52 else 53 BUG(); 54 55 return fsnotify(inode, fsnotify_mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 56 } 57 58 /* 59 * fsnotify_d_move - dentry has been moved 60 * Called with dcache_lock and dentry->d_lock held. 61 */ 62 static inline void fsnotify_d_move(struct dentry *dentry) 63 { 64 /* 65 * On move we need to update dentry->d_flags to indicate if the new parent 66 * cares about events from this dentry. 67 */ 68 __fsnotify_update_dcache_flags(dentry); 69 } 70 71 /* 72 * fsnotify_link_count - inode's link count changed 73 */ 74 static inline void fsnotify_link_count(struct inode *inode) 75 { 76 fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 77 } 78 79 /* 80 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir 81 */ 82 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, 83 const unsigned char *old_name, 84 int isdir, struct inode *target, struct dentry *moved) 85 { 86 struct inode *source = moved->d_inode; 87 u32 fs_cookie = fsnotify_get_cookie(); 88 __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM); 89 __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO); 90 const unsigned char *new_name = moved->d_name.name; 91 92 if (old_dir == new_dir) 93 old_dir_mask |= FS_DN_RENAME; 94 95 if (isdir) { 96 old_dir_mask |= FS_IN_ISDIR; 97 new_dir_mask |= FS_IN_ISDIR; 98 } 99 100 fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie); 101 fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie); 102 103 if (target) 104 fsnotify_link_count(target); 105 106 if (source) 107 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0); 108 audit_inode_child(moved, new_dir); 109 } 110 111 /* 112 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed 113 */ 114 static inline void fsnotify_inode_delete(struct inode *inode) 115 { 116 __fsnotify_inode_delete(inode); 117 } 118 119 /* 120 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed 121 */ 122 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt) 123 { 124 __fsnotify_vfsmount_delete(mnt); 125 } 126 127 /* 128 * fsnotify_nameremove - a filename was removed from a directory 129 */ 130 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir) 131 { 132 __u32 mask = FS_DELETE; 133 134 if (isdir) 135 mask |= FS_IN_ISDIR; 136 137 fsnotify_parent(NULL, dentry, mask); 138 } 139 140 /* 141 * fsnotify_inoderemove - an inode is going away 142 */ 143 static inline void fsnotify_inoderemove(struct inode *inode) 144 { 145 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 146 __fsnotify_inode_delete(inode); 147 } 148 149 /* 150 * fsnotify_create - 'name' was linked in 151 */ 152 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry) 153 { 154 audit_inode_child(dentry, inode); 155 156 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 157 } 158 159 /* 160 * fsnotify_link - new hardlink in 'inode' directory 161 * Note: We have to pass also the linked inode ptr as some filesystems leave 162 * new_dentry->d_inode NULL and instantiate inode pointer later 163 */ 164 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry) 165 { 166 fsnotify_link_count(inode); 167 audit_inode_child(new_dentry, dir); 168 169 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0); 170 } 171 172 /* 173 * fsnotify_mkdir - directory 'name' was created 174 */ 175 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) 176 { 177 __u32 mask = (FS_CREATE | FS_IN_ISDIR); 178 struct inode *d_inode = dentry->d_inode; 179 180 audit_inode_child(dentry, inode); 181 182 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 183 } 184 185 /* 186 * fsnotify_access - file was read 187 */ 188 static inline void fsnotify_access(struct file *file) 189 { 190 struct path *path = &file->f_path; 191 struct inode *inode = path->dentry->d_inode; 192 __u32 mask = FS_ACCESS; 193 194 if (S_ISDIR(inode->i_mode)) 195 mask |= FS_IN_ISDIR; 196 197 if (!(file->f_mode & FMODE_NONOTIFY)) { 198 fsnotify_parent(path, NULL, mask); 199 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 200 } 201 } 202 203 /* 204 * fsnotify_modify - file was modified 205 */ 206 static inline void fsnotify_modify(struct file *file) 207 { 208 struct path *path = &file->f_path; 209 struct inode *inode = path->dentry->d_inode; 210 __u32 mask = FS_MODIFY; 211 212 if (S_ISDIR(inode->i_mode)) 213 mask |= FS_IN_ISDIR; 214 215 if (!(file->f_mode & FMODE_NONOTIFY)) { 216 fsnotify_parent(path, NULL, mask); 217 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 218 } 219 } 220 221 /* 222 * fsnotify_open - file was opened 223 */ 224 static inline void fsnotify_open(struct file *file) 225 { 226 struct path *path = &file->f_path; 227 struct inode *inode = path->dentry->d_inode; 228 __u32 mask = FS_OPEN; 229 230 if (S_ISDIR(inode->i_mode)) 231 mask |= FS_IN_ISDIR; 232 233 if (!(file->f_mode & FMODE_NONOTIFY)) { 234 fsnotify_parent(path, NULL, mask); 235 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 236 } 237 } 238 239 /* 240 * fsnotify_close - file was closed 241 */ 242 static inline void fsnotify_close(struct file *file) 243 { 244 struct path *path = &file->f_path; 245 struct inode *inode = file->f_path.dentry->d_inode; 246 fmode_t mode = file->f_mode; 247 __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE; 248 249 if (S_ISDIR(inode->i_mode)) 250 mask |= FS_IN_ISDIR; 251 252 if (!(file->f_mode & FMODE_NONOTIFY)) { 253 fsnotify_parent(path, NULL, mask); 254 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 255 } 256 } 257 258 /* 259 * fsnotify_xattr - extended attributes were changed 260 */ 261 static inline void fsnotify_xattr(struct dentry *dentry) 262 { 263 struct inode *inode = dentry->d_inode; 264 __u32 mask = FS_ATTRIB; 265 266 if (S_ISDIR(inode->i_mode)) 267 mask |= FS_IN_ISDIR; 268 269 fsnotify_parent(NULL, dentry, mask); 270 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 271 } 272 273 /* 274 * fsnotify_change - notify_change event. file was modified and/or metadata 275 * was changed. 276 */ 277 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid) 278 { 279 struct inode *inode = dentry->d_inode; 280 __u32 mask = 0; 281 282 if (ia_valid & ATTR_UID) 283 mask |= FS_ATTRIB; 284 if (ia_valid & ATTR_GID) 285 mask |= FS_ATTRIB; 286 if (ia_valid & ATTR_SIZE) 287 mask |= FS_MODIFY; 288 289 /* both times implies a utime(s) call */ 290 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) 291 mask |= FS_ATTRIB; 292 else if (ia_valid & ATTR_ATIME) 293 mask |= FS_ACCESS; 294 else if (ia_valid & ATTR_MTIME) 295 mask |= FS_MODIFY; 296 297 if (ia_valid & ATTR_MODE) 298 mask |= FS_ATTRIB; 299 300 if (mask) { 301 if (S_ISDIR(inode->i_mode)) 302 mask |= FS_IN_ISDIR; 303 304 fsnotify_parent(NULL, dentry, mask); 305 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 306 } 307 } 308 309 #if defined(CONFIG_FSNOTIFY) /* notify helpers */ 310 311 /* 312 * fsnotify_oldname_init - save off the old filename before we change it 313 */ 314 static inline const unsigned char *fsnotify_oldname_init(const unsigned char *name) 315 { 316 return kstrdup(name, GFP_KERNEL); 317 } 318 319 /* 320 * fsnotify_oldname_free - free the name we got from fsnotify_oldname_init 321 */ 322 static inline void fsnotify_oldname_free(const unsigned char *old_name) 323 { 324 kfree(old_name); 325 } 326 327 #else /* CONFIG_FSNOTIFY */ 328 329 static inline const char *fsnotify_oldname_init(const unsigned char *name) 330 { 331 return NULL; 332 } 333 334 static inline void fsnotify_oldname_free(const unsigned char *old_name) 335 { 336 } 337 338 #endif /* CONFIG_FSNOTIFY */ 339 340 #endif /* _LINUX_FS_NOTIFY_H */ 341