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(const 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 const struct path *path = &file->f_path; 32 /* 33 * Do not use file_inode() here or anywhere in this file to get the 34 * inode. That would break *notity on overlayfs. 35 */ 36 struct inode *inode = path->dentry->d_inode; 37 __u32 fsnotify_mask = 0; 38 int ret; 39 40 if (file->f_mode & FMODE_NONOTIFY) 41 return 0; 42 if (!(mask & (MAY_READ | MAY_OPEN))) 43 return 0; 44 if (mask & MAY_OPEN) 45 fsnotify_mask = FS_OPEN_PERM; 46 else if (mask & MAY_READ) 47 fsnotify_mask = FS_ACCESS_PERM; 48 else 49 BUG(); 50 51 ret = fsnotify_parent(path, NULL, fsnotify_mask); 52 if (ret) 53 return ret; 54 55 return fsnotify(inode, fsnotify_mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 56 } 57 58 /* 59 * fsnotify_link_count - inode's link count changed 60 */ 61 static inline void fsnotify_link_count(struct inode *inode) 62 { 63 fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 64 } 65 66 /* 67 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir 68 */ 69 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, 70 const unsigned char *old_name, 71 int isdir, struct inode *target, struct dentry *moved) 72 { 73 struct inode *source = moved->d_inode; 74 u32 fs_cookie = fsnotify_get_cookie(); 75 __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM); 76 __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO); 77 const unsigned char *new_name = moved->d_name.name; 78 79 if (old_dir == new_dir) 80 old_dir_mask |= FS_DN_RENAME; 81 82 if (isdir) { 83 old_dir_mask |= FS_ISDIR; 84 new_dir_mask |= FS_ISDIR; 85 } 86 87 fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name, 88 fs_cookie); 89 fsnotify(new_dir, new_dir_mask, source, FSNOTIFY_EVENT_INODE, new_name, 90 fs_cookie); 91 92 if (target) 93 fsnotify_link_count(target); 94 95 if (source) 96 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0); 97 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE); 98 } 99 100 /* 101 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed 102 */ 103 static inline void fsnotify_inode_delete(struct inode *inode) 104 { 105 __fsnotify_inode_delete(inode); 106 } 107 108 /* 109 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed 110 */ 111 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt) 112 { 113 __fsnotify_vfsmount_delete(mnt); 114 } 115 116 /* 117 * fsnotify_nameremove - a filename was removed from a directory 118 */ 119 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir) 120 { 121 __u32 mask = FS_DELETE; 122 123 if (isdir) 124 mask |= FS_ISDIR; 125 126 fsnotify_parent(NULL, dentry, mask); 127 } 128 129 /* 130 * fsnotify_inoderemove - an inode is going away 131 */ 132 static inline void fsnotify_inoderemove(struct inode *inode) 133 { 134 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 135 __fsnotify_inode_delete(inode); 136 } 137 138 /* 139 * fsnotify_create - 'name' was linked in 140 */ 141 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry) 142 { 143 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); 144 145 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 146 } 147 148 /* 149 * fsnotify_link - new hardlink in 'inode' directory 150 * Note: We have to pass also the linked inode ptr as some filesystems leave 151 * new_dentry->d_inode NULL and instantiate inode pointer later 152 */ 153 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry) 154 { 155 fsnotify_link_count(inode); 156 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE); 157 158 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0); 159 } 160 161 /* 162 * fsnotify_mkdir - directory 'name' was created 163 */ 164 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) 165 { 166 __u32 mask = (FS_CREATE | FS_ISDIR); 167 struct inode *d_inode = dentry->d_inode; 168 169 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); 170 171 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0); 172 } 173 174 /* 175 * fsnotify_access - file was read 176 */ 177 static inline void fsnotify_access(struct file *file) 178 { 179 const struct path *path = &file->f_path; 180 struct inode *inode = path->dentry->d_inode; 181 __u32 mask = FS_ACCESS; 182 183 if (S_ISDIR(inode->i_mode)) 184 mask |= FS_ISDIR; 185 186 if (!(file->f_mode & FMODE_NONOTIFY)) { 187 fsnotify_parent(path, NULL, mask); 188 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 189 } 190 } 191 192 /* 193 * fsnotify_modify - file was modified 194 */ 195 static inline void fsnotify_modify(struct file *file) 196 { 197 const struct path *path = &file->f_path; 198 struct inode *inode = path->dentry->d_inode; 199 __u32 mask = FS_MODIFY; 200 201 if (S_ISDIR(inode->i_mode)) 202 mask |= FS_ISDIR; 203 204 if (!(file->f_mode & FMODE_NONOTIFY)) { 205 fsnotify_parent(path, NULL, mask); 206 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 207 } 208 } 209 210 /* 211 * fsnotify_open - file was opened 212 */ 213 static inline void fsnotify_open(struct file *file) 214 { 215 const struct path *path = &file->f_path; 216 struct inode *inode = path->dentry->d_inode; 217 __u32 mask = FS_OPEN; 218 219 if (S_ISDIR(inode->i_mode)) 220 mask |= FS_ISDIR; 221 222 fsnotify_parent(path, NULL, mask); 223 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 224 } 225 226 /* 227 * fsnotify_close - file was closed 228 */ 229 static inline void fsnotify_close(struct file *file) 230 { 231 const struct path *path = &file->f_path; 232 struct inode *inode = path->dentry->d_inode; 233 fmode_t mode = file->f_mode; 234 __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE; 235 236 if (S_ISDIR(inode->i_mode)) 237 mask |= FS_ISDIR; 238 239 if (!(file->f_mode & FMODE_NONOTIFY)) { 240 fsnotify_parent(path, NULL, mask); 241 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); 242 } 243 } 244 245 /* 246 * fsnotify_xattr - extended attributes were changed 247 */ 248 static inline void fsnotify_xattr(struct dentry *dentry) 249 { 250 struct inode *inode = dentry->d_inode; 251 __u32 mask = FS_ATTRIB; 252 253 if (S_ISDIR(inode->i_mode)) 254 mask |= FS_ISDIR; 255 256 fsnotify_parent(NULL, dentry, mask); 257 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 258 } 259 260 /* 261 * fsnotify_change - notify_change event. file was modified and/or metadata 262 * was changed. 263 */ 264 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid) 265 { 266 struct inode *inode = dentry->d_inode; 267 __u32 mask = 0; 268 269 if (ia_valid & ATTR_UID) 270 mask |= FS_ATTRIB; 271 if (ia_valid & ATTR_GID) 272 mask |= FS_ATTRIB; 273 if (ia_valid & ATTR_SIZE) 274 mask |= FS_MODIFY; 275 276 /* both times implies a utime(s) call */ 277 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) 278 mask |= FS_ATTRIB; 279 else if (ia_valid & ATTR_ATIME) 280 mask |= FS_ACCESS; 281 else if (ia_valid & ATTR_MTIME) 282 mask |= FS_MODIFY; 283 284 if (ia_valid & ATTR_MODE) 285 mask |= FS_ATTRIB; 286 287 if (mask) { 288 if (S_ISDIR(inode->i_mode)) 289 mask |= FS_ISDIR; 290 291 fsnotify_parent(NULL, dentry, mask); 292 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0); 293 } 294 } 295 296 #endif /* _LINUX_FS_NOTIFY_H */ 297