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 /* Notify this dentry's parent about a child's events. */ 20 static inline int fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask) 21 { 22 if (!dentry) 23 dentry = path->dentry; 24 25 return __fsnotify_parent(path, dentry, mask); 26 } 27 28 /* simple call site for access decisions */ 29 static inline int fsnotify_perm(struct file *file, int mask) 30 { 31 struct path *path = &file->f_path; 32 struct inode *inode = file_inode(file); 33 __u32 fsnotify_mask = 0; 34 int ret; 35 36 if (file->f_mode & FMODE_NONOTIFY) 37 return 0; 38 if (!(mask & (MAY_READ | MAY_OPEN))) 39 return 0; 40 if (mask & MAY_OPEN) 41 fsnotify_mask = FS_OPEN_PERM; 42 else if (mask & MAY_READ) 43 fsnotify_mask = FS_ACCESS_PERM; 44 else 45 BUG(); 46 47 ret = fsnotify_parent(path, NULL, fsnotify_mask); 48 if (ret) 49 return ret; 50 51 return fsnotify(inode, fsnotify_mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 52 } 53 54 /* 55 * fsnotify_d_move - dentry has been moved 56 */ 57 static inline void fsnotify_d_move(struct dentry *dentry) 58 { 59 /* 60 * On move we need to update dentry->d_flags to indicate if the new parent 61 * cares about events from this dentry. 62 */ 63 __fsnotify_update_dcache_flags(dentry); 64 } 65 66 /* 67 * fsnotify_link_count - inode's link count changed 68 */ 69 static inline void fsnotify_link_count(struct inode *inode) 70 { 71 fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 72 } 73 74 /* 75 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir 76 */ 77 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, 78 const unsigned char *old_name, 79 int isdir, struct inode *target, struct dentry *moved) 80 { 81 struct inode *source = moved->d_inode; 82 u32 fs_cookie = fsnotify_get_cookie(); 83 __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM); 84 __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO); 85 const unsigned char *new_name = moved->d_name.name; 86 87 if (old_dir == new_dir) 88 old_dir_mask |= FS_DN_RENAME; 89 90 if (isdir) { 91 old_dir_mask |= FS_ISDIR; 92 new_dir_mask |= FS_ISDIR; 93 } 94 95 fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name, 96 fs_cookie); 97 fsnotify(new_dir, new_dir_mask, source, FSNOTIFY_EVENT_INODE, new_name, 98 fs_cookie); 99 100 if (target) 101 fsnotify_link_count(target); 102 103 if (source) 104 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0); 105 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE); 106 } 107 108 /* 109 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed 110 */ 111 static inline void fsnotify_inode_delete(struct inode *inode) 112 { 113 __fsnotify_inode_delete(inode); 114 } 115 116 /* 117 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed 118 */ 119 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt) 120 { 121 __fsnotify_vfsmount_delete(mnt); 122 } 123 124 /* 125 * fsnotify_nameremove - a filename was removed from a directory 126 */ 127 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir) 128 { 129 __u32 mask = FS_DELETE; 130 131 if (isdir) 132 mask |= FS_ISDIR; 133 134 fsnotify_parent(NULL, dentry, mask); 135 } 136 137 /* 138 * fsnotify_inoderemove - an inode is going away 139 */ 140 static inline void fsnotify_inoderemove(struct inode *inode) 141 { 142 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 143 __fsnotify_inode_delete(inode); 144 } 145 146 /* 147 * fsnotify_create - 'name' was linked in 148 */ 149 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry) 150 { 151 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); 152 153 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 154 } 155 156 /* 157 * fsnotify_link - new hardlink in 'inode' directory 158 * Note: We have to pass also the linked inode ptr as some filesystems leave 159 * new_dentry->d_inode NULL and instantiate inode pointer later 160 */ 161 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry) 162 { 163 fsnotify_link_count(inode); 164 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE); 165 166 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0); 167 } 168 169 /* 170 * fsnotify_mkdir - directory 'name' was created 171 */ 172 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) 173 { 174 __u32 mask = (FS_CREATE | FS_ISDIR); 175 struct inode *d_inode = dentry->d_inode; 176 177 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); 178 179 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 180 } 181 182 /* 183 * fsnotify_access - file was read 184 */ 185 static inline void fsnotify_access(struct file *file) 186 { 187 struct path *path = &file->f_path; 188 struct inode *inode = file_inode(file); 189 __u32 mask = FS_ACCESS; 190 191 if (S_ISDIR(inode->i_mode)) 192 mask |= FS_ISDIR; 193 194 if (!(file->f_mode & FMODE_NONOTIFY)) { 195 fsnotify_parent(path, NULL, mask); 196 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 197 } 198 } 199 200 /* 201 * fsnotify_modify - file was modified 202 */ 203 static inline void fsnotify_modify(struct file *file) 204 { 205 struct path *path = &file->f_path; 206 struct inode *inode = file_inode(file); 207 __u32 mask = FS_MODIFY; 208 209 if (S_ISDIR(inode->i_mode)) 210 mask |= FS_ISDIR; 211 212 if (!(file->f_mode & FMODE_NONOTIFY)) { 213 fsnotify_parent(path, NULL, mask); 214 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, 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 path *path = &file->f_path; 224 struct inode *inode = file_inode(file); 225 __u32 mask = FS_OPEN; 226 227 if (S_ISDIR(inode->i_mode)) 228 mask |= FS_ISDIR; 229 230 fsnotify_parent(path, NULL, mask); 231 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 232 } 233 234 /* 235 * fsnotify_close - file was closed 236 */ 237 static inline void fsnotify_close(struct file *file) 238 { 239 struct path *path = &file->f_path; 240 struct inode *inode = file_inode(file); 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_ISDIR; 246 247 if (!(file->f_mode & FMODE_NONOTIFY)) { 248 fsnotify_parent(path, NULL, mask); 249 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, 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_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_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