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 #include <linux/bug.h> 18 19 /* 20 * fsnotify_d_instantiate - instantiate a dentry for inode 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 int fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask) 30 { 31 if (!dentry) 32 dentry = path->dentry; 33 34 return __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 = file_inode(file); 42 __u32 fsnotify_mask = 0; 43 int ret; 44 45 if (file->f_mode & FMODE_NONOTIFY) 46 return 0; 47 if (!(mask & (MAY_READ | MAY_OPEN))) 48 return 0; 49 if (mask & MAY_OPEN) 50 fsnotify_mask = FS_OPEN_PERM; 51 else if (mask & MAY_READ) 52 fsnotify_mask = FS_ACCESS_PERM; 53 else 54 BUG(); 55 56 ret = fsnotify_parent(path, NULL, fsnotify_mask); 57 if (ret) 58 return ret; 59 60 return fsnotify(inode, fsnotify_mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 61 } 62 63 /* 64 * fsnotify_d_move - dentry has been moved 65 */ 66 static inline void fsnotify_d_move(struct dentry *dentry) 67 { 68 /* 69 * On move we need to update dentry->d_flags to indicate if the new parent 70 * cares about events from this dentry. 71 */ 72 __fsnotify_update_dcache_flags(dentry); 73 } 74 75 /* 76 * fsnotify_link_count - inode's link count changed 77 */ 78 static inline void fsnotify_link_count(struct inode *inode) 79 { 80 fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 81 } 82 83 /* 84 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir 85 */ 86 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, 87 const unsigned char *old_name, 88 int isdir, struct inode *target, struct dentry *moved) 89 { 90 struct inode *source = moved->d_inode; 91 u32 fs_cookie = fsnotify_get_cookie(); 92 __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM); 93 __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO); 94 const unsigned char *new_name = moved->d_name.name; 95 96 if (old_dir == new_dir) 97 old_dir_mask |= FS_DN_RENAME; 98 99 if (isdir) { 100 old_dir_mask |= FS_ISDIR; 101 new_dir_mask |= FS_ISDIR; 102 } 103 104 fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name, 105 fs_cookie); 106 fsnotify(new_dir, new_dir_mask, source, FSNOTIFY_EVENT_INODE, new_name, 107 fs_cookie); 108 109 if (target) 110 fsnotify_link_count(target); 111 112 if (source) 113 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0); 114 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE); 115 } 116 117 /* 118 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed 119 */ 120 static inline void fsnotify_inode_delete(struct inode *inode) 121 { 122 __fsnotify_inode_delete(inode); 123 } 124 125 /* 126 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed 127 */ 128 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt) 129 { 130 __fsnotify_vfsmount_delete(mnt); 131 } 132 133 /* 134 * fsnotify_nameremove - a filename was removed from a directory 135 */ 136 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir) 137 { 138 __u32 mask = FS_DELETE; 139 140 if (isdir) 141 mask |= FS_ISDIR; 142 143 fsnotify_parent(NULL, dentry, mask); 144 } 145 146 /* 147 * fsnotify_inoderemove - an inode is going away 148 */ 149 static inline void fsnotify_inoderemove(struct inode *inode) 150 { 151 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 152 __fsnotify_inode_delete(inode); 153 } 154 155 /* 156 * fsnotify_create - 'name' was linked in 157 */ 158 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry) 159 { 160 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); 161 162 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 163 } 164 165 /* 166 * fsnotify_link - new hardlink in 'inode' directory 167 * Note: We have to pass also the linked inode ptr as some filesystems leave 168 * new_dentry->d_inode NULL and instantiate inode pointer later 169 */ 170 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry) 171 { 172 fsnotify_link_count(inode); 173 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE); 174 175 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0); 176 } 177 178 /* 179 * fsnotify_mkdir - directory 'name' was created 180 */ 181 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) 182 { 183 __u32 mask = (FS_CREATE | FS_ISDIR); 184 struct inode *d_inode = dentry->d_inode; 185 186 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); 187 188 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 189 } 190 191 /* 192 * fsnotify_access - file was read 193 */ 194 static inline void fsnotify_access(struct file *file) 195 { 196 struct path *path = &file->f_path; 197 struct inode *inode = file_inode(file); 198 __u32 mask = FS_ACCESS; 199 200 if (S_ISDIR(inode->i_mode)) 201 mask |= FS_ISDIR; 202 203 if (!(file->f_mode & FMODE_NONOTIFY)) { 204 fsnotify_parent(path, NULL, mask); 205 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 206 } 207 } 208 209 /* 210 * fsnotify_modify - file was modified 211 */ 212 static inline void fsnotify_modify(struct file *file) 213 { 214 struct path *path = &file->f_path; 215 struct inode *inode = file_inode(file); 216 __u32 mask = FS_MODIFY; 217 218 if (S_ISDIR(inode->i_mode)) 219 mask |= FS_ISDIR; 220 221 if (!(file->f_mode & FMODE_NONOTIFY)) { 222 fsnotify_parent(path, NULL, mask); 223 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 224 } 225 } 226 227 /* 228 * fsnotify_open - file was opened 229 */ 230 static inline void fsnotify_open(struct file *file) 231 { 232 struct path *path = &file->f_path; 233 struct inode *inode = file_inode(file); 234 __u32 mask = FS_OPEN; 235 236 if (S_ISDIR(inode->i_mode)) 237 mask |= FS_ISDIR; 238 239 fsnotify_parent(path, NULL, mask); 240 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 241 } 242 243 /* 244 * fsnotify_close - file was closed 245 */ 246 static inline void fsnotify_close(struct file *file) 247 { 248 struct path *path = &file->f_path; 249 struct inode *inode = file_inode(file); 250 fmode_t mode = file->f_mode; 251 __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE; 252 253 if (S_ISDIR(inode->i_mode)) 254 mask |= FS_ISDIR; 255 256 if (!(file->f_mode & FMODE_NONOTIFY)) { 257 fsnotify_parent(path, NULL, mask); 258 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 259 } 260 } 261 262 /* 263 * fsnotify_xattr - extended attributes were changed 264 */ 265 static inline void fsnotify_xattr(struct dentry *dentry) 266 { 267 struct inode *inode = dentry->d_inode; 268 __u32 mask = FS_ATTRIB; 269 270 if (S_ISDIR(inode->i_mode)) 271 mask |= FS_ISDIR; 272 273 fsnotify_parent(NULL, dentry, mask); 274 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 275 } 276 277 /* 278 * fsnotify_change - notify_change event. file was modified and/or metadata 279 * was changed. 280 */ 281 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid) 282 { 283 struct inode *inode = dentry->d_inode; 284 __u32 mask = 0; 285 286 if (ia_valid & ATTR_UID) 287 mask |= FS_ATTRIB; 288 if (ia_valid & ATTR_GID) 289 mask |= FS_ATTRIB; 290 if (ia_valid & ATTR_SIZE) 291 mask |= FS_MODIFY; 292 293 /* both times implies a utime(s) call */ 294 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) 295 mask |= FS_ATTRIB; 296 else if (ia_valid & ATTR_ATIME) 297 mask |= FS_ACCESS; 298 else if (ia_valid & ATTR_MTIME) 299 mask |= FS_MODIFY; 300 301 if (ia_valid & ATTR_MODE) 302 mask |= FS_ATTRIB; 303 304 if (mask) { 305 if (S_ISDIR(inode->i_mode)) 306 mask |= FS_ISDIR; 307 308 fsnotify_parent(NULL, dentry, mask); 309 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 310 } 311 } 312 313 #if defined(CONFIG_FSNOTIFY) /* notify helpers */ 314 315 /* 316 * fsnotify_oldname_init - save off the old filename before we change it 317 */ 318 static inline const unsigned char *fsnotify_oldname_init(const unsigned char *name) 319 { 320 return kstrdup(name, GFP_KERNEL); 321 } 322 323 /* 324 * fsnotify_oldname_free - free the name we got from fsnotify_oldname_init 325 */ 326 static inline void fsnotify_oldname_free(const unsigned char *old_name) 327 { 328 kfree(old_name); 329 } 330 331 #else /* CONFIG_FSNOTIFY */ 332 333 static inline const char *fsnotify_oldname_init(const unsigned char *name) 334 { 335 return NULL; 336 } 337 338 static inline void fsnotify_oldname_free(const unsigned char *old_name) 339 { 340 } 341 342 #endif /* CONFIG_FSNOTIFY */ 343 344 #endif /* _LINUX_FS_NOTIFY_H */ 345