1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_FS_NOTIFY_H
3 #define _LINUX_FS_NOTIFY_H
6 * include/linux/fsnotify.h - generic hooks for filesystem notification, to
7 * reduce in-source duplication from both dnotify and inotify.
9 * We don't compile any of this away in some complicated menagerie of ifdefs.
10 * Instead, we rely on the code inside to optimize away as needed.
12 * (C) Copyright 2005 Robert Love
15 #include <linux/fsnotify_backend.h>
16 #include <linux/audit.h>
17 #include <linux/slab.h>
18 #include <linux/bug.h>
21 * Notify this @dir inode about a change in a child directory entry.
22 * The directory entry may have turned positive or negative or its inode may
23 * have changed (i.e. renamed over).
25 * Unlike fsnotify_parent(), the event will be reported regardless of the
26 * FS_EVENT_ON_CHILD mask on the parent inode and will not be reported if only
27 * the child is interested and not the parent.
29 static inline int fsnotify_name(__u32 mask, const void *data, int data_type,
30 struct inode *dir, const struct qstr *name,
33 if (atomic_long_read(&dir->i_sb->s_fsnotify_connectors) == 0)
36 return fsnotify(mask, data, data_type, dir, name, NULL, cookie);
39 static inline void fsnotify_dirent(struct inode *dir, struct dentry *dentry,
42 fsnotify_name(mask, dentry, FSNOTIFY_EVENT_DENTRY, dir, &dentry->d_name, 0);
45 static inline void fsnotify_inode(struct inode *inode, __u32 mask)
47 if (atomic_long_read(&inode->i_sb->s_fsnotify_connectors) == 0)
50 if (S_ISDIR(inode->i_mode))
53 fsnotify(mask, inode, FSNOTIFY_EVENT_INODE, NULL, NULL, inode, 0);
56 /* Notify this dentry's parent about a child's events. */
57 static inline int fsnotify_parent(struct dentry *dentry, __u32 mask,
58 const void *data, int data_type)
60 struct inode *inode = d_inode(dentry);
62 if (atomic_long_read(&inode->i_sb->s_fsnotify_connectors) == 0)
65 if (S_ISDIR(inode->i_mode)) {
68 /* sb/mount marks are not interested in name of directory */
69 if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED))
73 /* disconnected dentry cannot notify parent */
77 return __fsnotify_parent(dentry, mask, data, data_type);
80 return fsnotify(mask, data, data_type, NULL, NULL, inode, 0);
84 * Simple wrappers to consolidate calls to fsnotify_parent() when an event
85 * is on a file/dentry.
87 static inline void fsnotify_dentry(struct dentry *dentry, __u32 mask)
89 fsnotify_parent(dentry, mask, dentry, FSNOTIFY_EVENT_DENTRY);
92 static inline int fsnotify_file(struct file *file, __u32 mask)
94 const struct path *path = &file->f_path;
96 if (file->f_mode & FMODE_NONOTIFY)
99 return fsnotify_parent(path->dentry, mask, path, FSNOTIFY_EVENT_PATH);
102 /* Simple call site for access decisions */
103 static inline int fsnotify_perm(struct file *file, int mask)
106 __u32 fsnotify_mask = 0;
108 if (!(mask & (MAY_READ | MAY_OPEN)))
111 if (mask & MAY_OPEN) {
112 fsnotify_mask = FS_OPEN_PERM;
114 if (file->f_flags & __FMODE_EXEC) {
115 ret = fsnotify_file(file, FS_OPEN_EXEC_PERM);
120 } else if (mask & MAY_READ) {
121 fsnotify_mask = FS_ACCESS_PERM;
124 return fsnotify_file(file, fsnotify_mask);
128 * fsnotify_link_count - inode's link count changed
130 static inline void fsnotify_link_count(struct inode *inode)
132 fsnotify_inode(inode, FS_ATTRIB);
136 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
138 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
139 const struct qstr *old_name,
140 int isdir, struct inode *target,
141 struct dentry *moved)
143 struct inode *source = moved->d_inode;
144 u32 fs_cookie = fsnotify_get_cookie();
145 __u32 old_dir_mask = FS_MOVED_FROM;
146 __u32 new_dir_mask = FS_MOVED_TO;
147 __u32 rename_mask = FS_RENAME;
148 const struct qstr *new_name = &moved->d_name;
151 old_dir_mask |= FS_ISDIR;
152 new_dir_mask |= FS_ISDIR;
153 rename_mask |= FS_ISDIR;
156 /* Event with information about both old and new parent+name */
157 fsnotify_name(rename_mask, moved, FSNOTIFY_EVENT_DENTRY,
158 old_dir, old_name, 0);
160 fsnotify_name(old_dir_mask, source, FSNOTIFY_EVENT_INODE,
161 old_dir, old_name, fs_cookie);
162 fsnotify_name(new_dir_mask, source, FSNOTIFY_EVENT_INODE,
163 new_dir, new_name, fs_cookie);
166 fsnotify_link_count(target);
167 fsnotify_inode(source, FS_MOVE_SELF);
168 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE);
172 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
174 static inline void fsnotify_inode_delete(struct inode *inode)
176 __fsnotify_inode_delete(inode);
180 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
182 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
184 __fsnotify_vfsmount_delete(mnt);
188 * fsnotify_inoderemove - an inode is going away
190 static inline void fsnotify_inoderemove(struct inode *inode)
192 fsnotify_inode(inode, FS_DELETE_SELF);
193 __fsnotify_inode_delete(inode);
197 * fsnotify_create - 'name' was linked in
199 * Caller must make sure that dentry->d_name is stable.
200 * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate
203 static inline void fsnotify_create(struct inode *dir, struct dentry *dentry)
205 audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE);
207 fsnotify_dirent(dir, dentry, FS_CREATE);
211 * fsnotify_link - new hardlink in 'inode' directory
213 * Caller must make sure that new_dentry->d_name is stable.
214 * Note: We have to pass also the linked inode ptr as some filesystems leave
215 * new_dentry->d_inode NULL and instantiate inode pointer later
217 static inline void fsnotify_link(struct inode *dir, struct inode *inode,
218 struct dentry *new_dentry)
220 fsnotify_link_count(inode);
221 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);
223 fsnotify_name(FS_CREATE, inode, FSNOTIFY_EVENT_INODE,
224 dir, &new_dentry->d_name, 0);
228 * fsnotify_unlink - 'name' was unlinked
230 * Caller must make sure that dentry->d_name is stable.
232 static inline void fsnotify_unlink(struct inode *dir, struct dentry *dentry)
234 /* Expected to be called before d_delete() */
235 WARN_ON_ONCE(d_is_negative(dentry));
237 fsnotify_dirent(dir, dentry, FS_DELETE);
241 * fsnotify_mkdir - directory 'name' was created
243 * Caller must make sure that dentry->d_name is stable.
244 * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate
247 static inline void fsnotify_mkdir(struct inode *dir, struct dentry *dentry)
249 audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE);
251 fsnotify_dirent(dir, dentry, FS_CREATE | FS_ISDIR);
255 * fsnotify_rmdir - directory 'name' was removed
257 * Caller must make sure that dentry->d_name is stable.
259 static inline void fsnotify_rmdir(struct inode *dir, struct dentry *dentry)
261 /* Expected to be called before d_delete() */
262 WARN_ON_ONCE(d_is_negative(dentry));
264 fsnotify_dirent(dir, dentry, FS_DELETE | FS_ISDIR);
268 * fsnotify_access - file was read
270 static inline void fsnotify_access(struct file *file)
272 fsnotify_file(file, FS_ACCESS);
276 * fsnotify_modify - file was modified
278 static inline void fsnotify_modify(struct file *file)
280 fsnotify_file(file, FS_MODIFY);
284 * fsnotify_open - file was opened
286 static inline void fsnotify_open(struct file *file)
288 __u32 mask = FS_OPEN;
290 if (file->f_flags & __FMODE_EXEC)
291 mask |= FS_OPEN_EXEC;
293 fsnotify_file(file, mask);
297 * fsnotify_close - file was closed
299 static inline void fsnotify_close(struct file *file)
301 __u32 mask = (file->f_mode & FMODE_WRITE) ? FS_CLOSE_WRITE :
304 fsnotify_file(file, mask);
308 * fsnotify_xattr - extended attributes were changed
310 static inline void fsnotify_xattr(struct dentry *dentry)
312 fsnotify_dentry(dentry, FS_ATTRIB);
316 * fsnotify_change - notify_change event. file was modified and/or metadata
319 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
323 if (ia_valid & ATTR_UID)
325 if (ia_valid & ATTR_GID)
327 if (ia_valid & ATTR_SIZE)
330 /* both times implies a utime(s) call */
331 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
333 else if (ia_valid & ATTR_ATIME)
335 else if (ia_valid & ATTR_MTIME)
338 if (ia_valid & ATTR_MODE)
342 fsnotify_dentry(dentry, mask);
345 static inline int fsnotify_sb_error(struct super_block *sb, struct inode *inode,
348 struct fs_error_report report = {
354 return fsnotify(FS_ERROR, &report, FSNOTIFY_EVENT_ERROR,
355 NULL, NULL, NULL, 0);
358 #endif /* _LINUX_FS_NOTIFY_H */