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 /*
20 * fsnotify_d_instantiate - instantiate a dentry for inode
21 */
fsnotify_d_instantiate(struct dentry * dentry,struct inode * inode)22 static inline void fsnotify_d_instantiate(struct dentry *dentry,
23 struct inode *inode)
24 {
25 __fsnotify_d_instantiate(dentry, inode);
26 }
27
28 /* Notify this dentry's parent about a child's events. */
fsnotify_parent(struct path * path,struct dentry * dentry,__u32 mask)29 static inline int fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask)
30 {
31 if (!dentry)
32 dentry = path->dentry;
33
34 return __fsnotify_parent(path, dentry, mask);
35 }
36
37 /* simple call site for access decisions */
fsnotify_perm(struct file * file,int mask)38 static inline int fsnotify_perm(struct file *file, int mask)
39 {
40 struct path *path = &file->f_path;
41 struct inode *inode = file_inode(file);
42 __u32 fsnotify_mask = 0;
43 int ret;
44
45 if (file->f_mode & FMODE_NONOTIFY)
46 return 0;
47 if (!(mask & (MAY_READ | MAY_OPEN)))
48 return 0;
49 if (mask & MAY_OPEN)
50 fsnotify_mask = FS_OPEN_PERM;
51 else if (mask & MAY_READ)
52 fsnotify_mask = FS_ACCESS_PERM;
53 else
54 BUG();
55
56 ret = fsnotify_parent(path, NULL, fsnotify_mask);
57 if (ret)
58 return ret;
59
60 return fsnotify(inode, fsnotify_mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
61 }
62
63 /*
64 * fsnotify_d_move - dentry has been moved
65 */
fsnotify_d_move(struct dentry * dentry)66 static inline void fsnotify_d_move(struct dentry *dentry)
67 {
68 /*
69 * On move we need to update dentry->d_flags to indicate if the new parent
70 * cares about events from this dentry.
71 */
72 __fsnotify_update_dcache_flags(dentry);
73 }
74
75 /*
76 * fsnotify_link_count - inode's link count changed
77 */
fsnotify_link_count(struct inode * inode)78 static inline void fsnotify_link_count(struct inode *inode)
79 {
80 fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
81 }
82
83 /*
84 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
85 */
fsnotify_move(struct inode * old_dir,struct inode * new_dir,const unsigned char * old_name,int isdir,struct inode * target,struct dentry * moved)86 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
87 const unsigned char *old_name,
88 int isdir, struct inode *target, struct dentry *moved)
89 {
90 struct inode *source = moved->d_inode;
91 u32 fs_cookie = fsnotify_get_cookie();
92 __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM);
93 __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO);
94 const unsigned char *new_name = moved->d_name.name;
95
96 if (old_dir == new_dir)
97 old_dir_mask |= FS_DN_RENAME;
98
99 if (isdir) {
100 old_dir_mask |= FS_ISDIR;
101 new_dir_mask |= FS_ISDIR;
102 }
103
104 fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name,
105 fs_cookie);
106 fsnotify(new_dir, new_dir_mask, source, FSNOTIFY_EVENT_INODE, new_name,
107 fs_cookie);
108
109 if (target)
110 fsnotify_link_count(target);
111
112 if (source)
113 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0);
114 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE);
115 }
116
117 /*
118 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
119 */
fsnotify_inode_delete(struct inode * inode)120 static inline void fsnotify_inode_delete(struct inode *inode)
121 {
122 __fsnotify_inode_delete(inode);
123 }
124
125 /*
126 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
127 */
fsnotify_vfsmount_delete(struct vfsmount * mnt)128 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
129 {
130 __fsnotify_vfsmount_delete(mnt);
131 }
132
133 /*
134 * fsnotify_nameremove - a filename was removed from a directory
135 */
fsnotify_nameremove(struct dentry * dentry,int isdir)136 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir)
137 {
138 __u32 mask = FS_DELETE;
139
140 if (isdir)
141 mask |= FS_ISDIR;
142
143 fsnotify_parent(NULL, dentry, mask);
144 }
145
146 /*
147 * fsnotify_inoderemove - an inode is going away
148 */
fsnotify_inoderemove(struct inode * inode)149 static inline void fsnotify_inoderemove(struct inode *inode)
150 {
151 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
152 __fsnotify_inode_delete(inode);
153 }
154
155 /*
156 * fsnotify_create - 'name' was linked in
157 */
fsnotify_create(struct inode * inode,struct dentry * dentry)158 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
159 {
160 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);
161
162 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
163 }
164
165 /*
166 * fsnotify_link - new hardlink in 'inode' directory
167 * Note: We have to pass also the linked inode ptr as some filesystems leave
168 * new_dentry->d_inode NULL and instantiate inode pointer later
169 */
fsnotify_link(struct inode * dir,struct inode * inode,struct dentry * new_dentry)170 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry)
171 {
172 fsnotify_link_count(inode);
173 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);
174
175 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0);
176 }
177
178 /*
179 * fsnotify_mkdir - directory 'name' was created
180 */
fsnotify_mkdir(struct inode * inode,struct dentry * dentry)181 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
182 {
183 __u32 mask = (FS_CREATE | FS_ISDIR);
184 struct inode *d_inode = dentry->d_inode;
185
186 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);
187
188 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
189 }
190
191 /*
192 * fsnotify_access - file was read
193 */
fsnotify_access(struct file * file)194 static inline void fsnotify_access(struct file *file)
195 {
196 struct path *path = &file->f_path;
197 struct inode *inode = file_inode(file);
198 __u32 mask = FS_ACCESS;
199
200 if (S_ISDIR(inode->i_mode))
201 mask |= FS_ISDIR;
202
203 if (!(file->f_mode & FMODE_NONOTIFY)) {
204 fsnotify_parent(path, NULL, mask);
205 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
206 }
207 }
208
209 /*
210 * fsnotify_modify - file was modified
211 */
fsnotify_modify(struct file * file)212 static inline void fsnotify_modify(struct file *file)
213 {
214 struct path *path = &file->f_path;
215 struct inode *inode = file_inode(file);
216 __u32 mask = FS_MODIFY;
217
218 if (S_ISDIR(inode->i_mode))
219 mask |= FS_ISDIR;
220
221 if (!(file->f_mode & FMODE_NONOTIFY)) {
222 fsnotify_parent(path, NULL, mask);
223 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
224 }
225 }
226
227 /*
228 * fsnotify_open - file was opened
229 */
fsnotify_open(struct file * file)230 static inline void fsnotify_open(struct file *file)
231 {
232 struct path *path = &file->f_path;
233 struct path lower_path;
234 struct inode *inode = file_inode(file);
235 __u32 mask = FS_OPEN;
236
237 if (S_ISDIR(inode->i_mode))
238 mask |= FS_ISDIR;
239
240 if (path->dentry->d_op && path->dentry->d_op->d_canonical_path) {
241 path->dentry->d_op->d_canonical_path(path, &lower_path);
242 fsnotify_parent(&lower_path, NULL, mask);
243 fsnotify(lower_path.dentry->d_inode, mask, &lower_path, FSNOTIFY_EVENT_PATH, NULL, 0);
244 path_put(&lower_path);
245 }
246 fsnotify_parent(path, NULL, mask);
247 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
248 }
249
250 /*
251 * fsnotify_close - file was closed
252 */
fsnotify_close(struct file * file)253 static inline void fsnotify_close(struct file *file)
254 {
255 struct path *path = &file->f_path;
256 struct inode *inode = file_inode(file);
257 fmode_t mode = file->f_mode;
258 __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE;
259
260 if (S_ISDIR(inode->i_mode))
261 mask |= FS_ISDIR;
262
263 if (!(file->f_mode & FMODE_NONOTIFY)) {
264 fsnotify_parent(path, NULL, mask);
265 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
266 }
267 }
268
269 /*
270 * fsnotify_xattr - extended attributes were changed
271 */
fsnotify_xattr(struct dentry * dentry)272 static inline void fsnotify_xattr(struct dentry *dentry)
273 {
274 struct inode *inode = dentry->d_inode;
275 __u32 mask = FS_ATTRIB;
276
277 if (S_ISDIR(inode->i_mode))
278 mask |= FS_ISDIR;
279
280 fsnotify_parent(NULL, dentry, mask);
281 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
282 }
283
284 /*
285 * fsnotify_change - notify_change event. file was modified and/or metadata
286 * was changed.
287 */
fsnotify_change(struct dentry * dentry,unsigned int ia_valid)288 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
289 {
290 struct inode *inode = dentry->d_inode;
291 __u32 mask = 0;
292
293 if (ia_valid & ATTR_UID)
294 mask |= FS_ATTRIB;
295 if (ia_valid & ATTR_GID)
296 mask |= FS_ATTRIB;
297 if (ia_valid & ATTR_SIZE)
298 mask |= FS_MODIFY;
299
300 /* both times implies a utime(s) call */
301 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
302 mask |= FS_ATTRIB;
303 else if (ia_valid & ATTR_ATIME)
304 mask |= FS_ACCESS;
305 else if (ia_valid & ATTR_MTIME)
306 mask |= FS_MODIFY;
307
308 if (ia_valid & ATTR_MODE)
309 mask |= FS_ATTRIB;
310
311 if (mask) {
312 if (S_ISDIR(inode->i_mode))
313 mask |= FS_ISDIR;
314
315 fsnotify_parent(NULL, dentry, mask);
316 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
317 }
318 }
319
320 #endif /* _LINUX_FS_NOTIFY_H */
321