xref: /linux-6.15/include/linux/fsnotify.h (revision f60d24d2)
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/dnotify.h>
15 #include <linux/inotify.h>
16 #include <linux/fsnotify_backend.h>
17 #include <linux/audit.h>
18 
19 /*
20  * fsnotify_d_instantiate - instantiate a dentry for inode
21  * Called with dcache_lock held.
22  */
23 static inline void fsnotify_d_instantiate(struct dentry *entry,
24 						struct inode *inode)
25 {
26 	__fsnotify_d_instantiate(entry, inode);
27 
28 	inotify_d_instantiate(entry, inode);
29 }
30 
31 /* Notify this dentry's parent about a child's events. */
32 static inline void fsnotify_parent(struct dentry *dentry, __u32 mask)
33 {
34 	__fsnotify_parent(dentry, mask);
35 
36 	inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name);
37 }
38 
39 /*
40  * fsnotify_d_move - entry has been moved
41  * Called with dcache_lock and entry->d_lock held.
42  */
43 static inline void fsnotify_d_move(struct dentry *entry)
44 {
45 	/*
46 	 * On move we need to update entry->d_flags to indicate if the new parent
47 	 * cares about events from this entry.
48 	 */
49 	__fsnotify_update_dcache_flags(entry);
50 
51 	inotify_d_move(entry);
52 }
53 
54 /*
55  * fsnotify_link_count - inode's link count changed
56  */
57 static inline void fsnotify_link_count(struct inode *inode)
58 {
59 	inotify_inode_queue_event(inode, IN_ATTRIB, 0, NULL, NULL);
60 
61 	fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
62 }
63 
64 /*
65  * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
66  */
67 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
68 				 const char *old_name, const char *new_name,
69 				 int isdir, struct inode *target, struct dentry *moved)
70 {
71 	struct inode *source = moved->d_inode;
72 	u32 in_cookie = inotify_get_cookie();
73 	u32 fs_cookie = fsnotify_get_cookie();
74 	__u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM);
75 	__u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO);
76 
77 	if (old_dir == new_dir)
78 		old_dir_mask |= FS_DN_RENAME;
79 
80 	if (isdir) {
81 		isdir = IN_ISDIR;
82 		old_dir_mask |= FS_IN_ISDIR;
83 		new_dir_mask |= FS_IN_ISDIR;
84 	}
85 
86 	inotify_inode_queue_event(old_dir, IN_MOVED_FROM|isdir, in_cookie, old_name,
87 				  source);
88 	inotify_inode_queue_event(new_dir, IN_MOVED_TO|isdir, in_cookie, new_name,
89 				  source);
90 
91 	fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie);
92 	fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie);
93 
94 	if (target) {
95 		inotify_inode_queue_event(target, IN_DELETE_SELF, 0, NULL, NULL);
96 		inotify_inode_is_dead(target);
97 
98 		/* this is really a link_count change not a removal */
99 		fsnotify_link_count(target);
100 	}
101 
102 	if (source) {
103 		inotify_inode_queue_event(source, IN_MOVE_SELF, 0, NULL, NULL);
104 		fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0);
105 	}
106 	audit_inode_child(new_name, moved, new_dir);
107 }
108 
109 /*
110  * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
111  */
112 static inline void fsnotify_inode_delete(struct inode *inode)
113 {
114 	__fsnotify_inode_delete(inode);
115 }
116 
117 /*
118  * fsnotify_nameremove - a filename was removed from a directory
119  */
120 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir)
121 {
122 	__u32 mask = FS_DELETE;
123 
124 	if (isdir)
125 		mask |= FS_IN_ISDIR;
126 
127 	fsnotify_parent(dentry, mask);
128 }
129 
130 /*
131  * fsnotify_inoderemove - an inode is going away
132  */
133 static inline void fsnotify_inoderemove(struct inode *inode)
134 {
135 	inotify_inode_queue_event(inode, IN_DELETE_SELF, 0, NULL, NULL);
136 	inotify_inode_is_dead(inode);
137 
138 	fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
139 	__fsnotify_inode_delete(inode);
140 }
141 
142 /*
143  * fsnotify_create - 'name' was linked in
144  */
145 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
146 {
147 	inotify_inode_queue_event(inode, IN_CREATE, 0, dentry->d_name.name,
148 				  dentry->d_inode);
149 	audit_inode_child(dentry->d_name.name, dentry, inode);
150 
151 	fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
152 }
153 
154 /*
155  * fsnotify_link - new hardlink in 'inode' directory
156  * Note: We have to pass also the linked inode ptr as some filesystems leave
157  *   new_dentry->d_inode NULL and instantiate inode pointer later
158  */
159 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry)
160 {
161 	inotify_inode_queue_event(dir, IN_CREATE, 0, new_dentry->d_name.name,
162 				  inode);
163 	fsnotify_link_count(inode);
164 	audit_inode_child(new_dentry->d_name.name, new_dentry, dir);
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_IN_ISDIR);
175 	struct inode *d_inode = dentry->d_inode;
176 
177 	inotify_inode_queue_event(inode, mask, 0, dentry->d_name.name, d_inode);
178 	audit_inode_child(dentry->d_name.name, dentry, inode);
179 
180 	fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
181 }
182 
183 /*
184  * fsnotify_access - file was read
185  */
186 static inline void fsnotify_access(struct dentry *dentry)
187 {
188 	struct inode *inode = dentry->d_inode;
189 	__u32 mask = FS_ACCESS;
190 
191 	if (S_ISDIR(inode->i_mode))
192 		mask |= FS_IN_ISDIR;
193 
194 	inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
195 
196 	fsnotify_parent(dentry, mask);
197 	fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
198 }
199 
200 /*
201  * fsnotify_modify - file was modified
202  */
203 static inline void fsnotify_modify(struct dentry *dentry)
204 {
205 	struct inode *inode = dentry->d_inode;
206 	__u32 mask = FS_MODIFY;
207 
208 	if (S_ISDIR(inode->i_mode))
209 		mask |= FS_IN_ISDIR;
210 
211 	inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
212 
213 	fsnotify_parent(dentry, mask);
214 	fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
215 }
216 
217 /*
218  * fsnotify_open - file was opened
219  */
220 static inline void fsnotify_open(struct dentry *dentry)
221 {
222 	struct inode *inode = dentry->d_inode;
223 	__u32 mask = FS_OPEN;
224 
225 	if (S_ISDIR(inode->i_mode))
226 		mask |= FS_IN_ISDIR;
227 
228 	inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
229 
230 	fsnotify_parent(dentry, mask);
231 	fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
232 }
233 
234 /*
235  * fsnotify_close - file was closed
236  */
237 static inline void fsnotify_close(struct file *file)
238 {
239 	struct dentry *dentry = file->f_path.dentry;
240 	struct inode *inode = dentry->d_inode;
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_IN_ISDIR;
246 
247 	inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
248 
249 	fsnotify_parent(dentry, mask);
250 	fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0);
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_IN_ISDIR;
263 
264 	inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
265 
266 	fsnotify_parent(dentry, mask);
267 	fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
268 }
269 
270 /*
271  * fsnotify_change - notify_change event.  file was modified and/or metadata
272  * was changed.
273  */
274 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
275 {
276 	struct inode *inode = dentry->d_inode;
277 	__u32 mask = 0;
278 
279 	if (ia_valid & ATTR_UID)
280 		mask |= FS_ATTRIB;
281 	if (ia_valid & ATTR_GID)
282 		mask |= FS_ATTRIB;
283 	if (ia_valid & ATTR_SIZE)
284 		mask |= FS_MODIFY;
285 
286 	/* both times implies a utime(s) call */
287 	if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
288 		mask |= FS_ATTRIB;
289 	else if (ia_valid & ATTR_ATIME)
290 		mask |= FS_ACCESS;
291 	else if (ia_valid & ATTR_MTIME)
292 		mask |= FS_MODIFY;
293 
294 	if (ia_valid & ATTR_MODE)
295 		mask |= FS_ATTRIB;
296 
297 	if (mask) {
298 		if (S_ISDIR(inode->i_mode))
299 			mask |= FS_IN_ISDIR;
300 		inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
301 
302 		fsnotify_parent(dentry, mask);
303 		fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
304 	}
305 }
306 
307 #if defined(CONFIG_INOTIFY) || defined(CONFIG_FSNOTIFY)	/* notify helpers */
308 
309 /*
310  * fsnotify_oldname_init - save off the old filename before we change it
311  */
312 static inline const char *fsnotify_oldname_init(const char *name)
313 {
314 	return kstrdup(name, GFP_KERNEL);
315 }
316 
317 /*
318  * fsnotify_oldname_free - free the name we got from fsnotify_oldname_init
319  */
320 static inline void fsnotify_oldname_free(const char *old_name)
321 {
322 	kfree(old_name);
323 }
324 
325 #else	/* CONFIG_INOTIFY || CONFIG_FSNOTIFY */
326 
327 static inline const char *fsnotify_oldname_init(const char *name)
328 {
329 	return NULL;
330 }
331 
332 static inline void fsnotify_oldname_free(const char *old_name)
333 {
334 }
335 
336 #endif	/* ! CONFIG_INOTIFY */
337 
338 #endif	/* _LINUX_FS_NOTIFY_H */
339