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 const struct qstr *new_name = &moved->d_name;
149 if (old_dir == new_dir)
150 old_dir_mask |= FS_DN_RENAME;
153 old_dir_mask |= FS_ISDIR;
154 new_dir_mask |= FS_ISDIR;
157 fsnotify_name(old_dir_mask, source, FSNOTIFY_EVENT_INODE,
158 old_dir, old_name, fs_cookie);
159 fsnotify_name(new_dir_mask, source, FSNOTIFY_EVENT_INODE,
160 new_dir, new_name, fs_cookie);
163 fsnotify_link_count(target);
164 fsnotify_inode(source, FS_MOVE_SELF);
165 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE);
169 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
171 static inline void fsnotify_inode_delete(struct inode *inode)
173 __fsnotify_inode_delete(inode);
177 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
179 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
181 __fsnotify_vfsmount_delete(mnt);
185 * fsnotify_inoderemove - an inode is going away
187 static inline void fsnotify_inoderemove(struct inode *inode)
189 fsnotify_inode(inode, FS_DELETE_SELF);
190 __fsnotify_inode_delete(inode);
194 * fsnotify_create - 'name' was linked in
196 * Caller must make sure that dentry->d_name is stable.
197 * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate
200 static inline void fsnotify_create(struct inode *dir, struct dentry *dentry)
202 audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE);
204 fsnotify_dirent(dir, dentry, FS_CREATE);
208 * fsnotify_link - new hardlink in 'inode' directory
210 * Caller must make sure that new_dentry->d_name is stable.
211 * Note: We have to pass also the linked inode ptr as some filesystems leave
212 * new_dentry->d_inode NULL and instantiate inode pointer later
214 static inline void fsnotify_link(struct inode *dir, struct inode *inode,
215 struct dentry *new_dentry)
217 fsnotify_link_count(inode);
218 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);
220 fsnotify_name(FS_CREATE, inode, FSNOTIFY_EVENT_INODE,
221 dir, &new_dentry->d_name, 0);
225 * fsnotify_unlink - 'name' was unlinked
227 * Caller must make sure that dentry->d_name is stable.
229 static inline void fsnotify_unlink(struct inode *dir, struct dentry *dentry)
231 /* Expected to be called before d_delete() */
232 WARN_ON_ONCE(d_is_negative(dentry));
234 fsnotify_dirent(dir, dentry, FS_DELETE);
238 * fsnotify_mkdir - directory 'name' was created
240 * Caller must make sure that dentry->d_name is stable.
241 * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate
244 static inline void fsnotify_mkdir(struct inode *dir, struct dentry *dentry)
246 audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE);
248 fsnotify_dirent(dir, dentry, FS_CREATE | FS_ISDIR);
252 * fsnotify_rmdir - directory 'name' was removed
254 * Caller must make sure that dentry->d_name is stable.
256 static inline void fsnotify_rmdir(struct inode *dir, struct dentry *dentry)
258 /* Expected to be called before d_delete() */
259 WARN_ON_ONCE(d_is_negative(dentry));
261 fsnotify_dirent(dir, dentry, FS_DELETE | FS_ISDIR);
265 * fsnotify_access - file was read
267 static inline void fsnotify_access(struct file *file)
269 fsnotify_file(file, FS_ACCESS);
273 * fsnotify_modify - file was modified
275 static inline void fsnotify_modify(struct file *file)
277 fsnotify_file(file, FS_MODIFY);
281 * fsnotify_open - file was opened
283 static inline void fsnotify_open(struct file *file)
285 __u32 mask = FS_OPEN;
287 if (file->f_flags & __FMODE_EXEC)
288 mask |= FS_OPEN_EXEC;
290 fsnotify_file(file, mask);
294 * fsnotify_close - file was closed
296 static inline void fsnotify_close(struct file *file)
298 __u32 mask = (file->f_mode & FMODE_WRITE) ? FS_CLOSE_WRITE :
301 fsnotify_file(file, mask);
305 * fsnotify_xattr - extended attributes were changed
307 static inline void fsnotify_xattr(struct dentry *dentry)
309 fsnotify_dentry(dentry, FS_ATTRIB);
313 * fsnotify_change - notify_change event. file was modified and/or metadata
316 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
320 if (ia_valid & ATTR_UID)
322 if (ia_valid & ATTR_GID)
324 if (ia_valid & ATTR_SIZE)
327 /* both times implies a utime(s) call */
328 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
330 else if (ia_valid & ATTR_ATIME)
332 else if (ia_valid & ATTR_MTIME)
335 if (ia_valid & ATTR_MODE)
339 fsnotify_dentry(dentry, mask);
342 static inline int fsnotify_sb_error(struct super_block *sb, struct inode *inode,
345 struct fs_error_report report = {
351 return fsnotify(FS_ERROR, &report, FSNOTIFY_EVENT_ERROR,
352 NULL, NULL, NULL, 0);
355 #endif /* _LINUX_FS_NOTIFY_H */