projects/linux·blob v3.15 · refs

342 lines · 8.3 KiB

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 */
22static 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. */
29static 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 */
38static 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 */
66static 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 */
78static 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 */
86static 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, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie);
105 fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie);
106
107 if (target)
108 fsnotify_link_count(target);
109
110 if (source)
111 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0);
112 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE);
113}
114
115/*
116 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
117 */
118static inline void fsnotify_inode_delete(struct inode *inode)
119{
120 __fsnotify_inode_delete(inode);
121}
122
123/*
124 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
125 */
126static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
127{
128 __fsnotify_vfsmount_delete(mnt);
129}
130
131/*
132 * fsnotify_nameremove - a filename was removed from a directory
133 */
134static inline void fsnotify_nameremove(struct dentry *dentry, int isdir)
135{
136 __u32 mask = FS_DELETE;
137
138 if (isdir)
139 mask |= FS_ISDIR;
140
141 fsnotify_parent(NULL, dentry, mask);
142}
143
144/*
145 * fsnotify_inoderemove - an inode is going away
146 */
147static inline void fsnotify_inoderemove(struct inode *inode)
148{
149 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
150 __fsnotify_inode_delete(inode);
151}
152
153/*
154 * fsnotify_create - 'name' was linked in
155 */
156static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
157{
158 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);
159
160 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
161}
162
163/*
164 * fsnotify_link - new hardlink in 'inode' directory
165 * Note: We have to pass also the linked inode ptr as some filesystems leave
166 * new_dentry->d_inode NULL and instantiate inode pointer later
167 */
168static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry)
169{
170 fsnotify_link_count(inode);
171 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);
172
173 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0);
174}
175
176/*
177 * fsnotify_mkdir - directory 'name' was created
178 */
179static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
180{
181 __u32 mask = (FS_CREATE | FS_ISDIR);
182 struct inode *d_inode = dentry->d_inode;
183
184 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);
185
186 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
187}
188
189/*
190 * fsnotify_access - file was read
191 */
192static inline void fsnotify_access(struct file *file)
193{
194 struct path *path = &file->f_path;
195 struct inode *inode = file_inode(file);
196 __u32 mask = FS_ACCESS;
197
198 if (S_ISDIR(inode->i_mode))
199 mask |= FS_ISDIR;
200
201 if (!(file->f_mode & FMODE_NONOTIFY)) {
202 fsnotify_parent(path, NULL, mask);
203 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
204 }
205}
206
207/*
208 * fsnotify_modify - file was modified
209 */
210static inline void fsnotify_modify(struct file *file)
211{
212 struct path *path = &file->f_path;
213 struct inode *inode = file_inode(file);
214 __u32 mask = FS_MODIFY;
215
216 if (S_ISDIR(inode->i_mode))
217 mask |= FS_ISDIR;
218
219 if (!(file->f_mode & FMODE_NONOTIFY)) {
220 fsnotify_parent(path, NULL, mask);
221 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
222 }
223}
224
225/*
226 * fsnotify_open - file was opened
227 */
228static inline void fsnotify_open(struct file *file)
229{
230 struct path *path = &file->f_path;
231 struct inode *inode = file_inode(file);
232 __u32 mask = FS_OPEN;
233
234 if (S_ISDIR(inode->i_mode))
235 mask |= FS_ISDIR;
236
237 fsnotify_parent(path, NULL, mask);
238 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
239}
240
241/*
242 * fsnotify_close - file was closed
243 */
244static inline void fsnotify_close(struct file *file)
245{
246 struct path *path = &file->f_path;
247 struct inode *inode = file_inode(file);
248 fmode_t mode = file->f_mode;
249 __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE;
250
251 if (S_ISDIR(inode->i_mode))
252 mask |= FS_ISDIR;
253
254 if (!(file->f_mode & FMODE_NONOTIFY)) {
255 fsnotify_parent(path, NULL, mask);
256 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
257 }
258}
259
260/*
261 * fsnotify_xattr - extended attributes were changed
262 */
263static inline void fsnotify_xattr(struct dentry *dentry)
264{
265 struct inode *inode = dentry->d_inode;
266 __u32 mask = FS_ATTRIB;
267
268 if (S_ISDIR(inode->i_mode))
269 mask |= FS_ISDIR;
270
271 fsnotify_parent(NULL, dentry, mask);
272 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
273}
274
275/*
276 * fsnotify_change - notify_change event. file was modified and/or metadata
277 * was changed.
278 */
279static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
280{
281 struct inode *inode = dentry->d_inode;
282 __u32 mask = 0;
283
284 if (ia_valid & ATTR_UID)
285 mask |= FS_ATTRIB;
286 if (ia_valid & ATTR_GID)
287 mask |= FS_ATTRIB;
288 if (ia_valid & ATTR_SIZE)
289 mask |= FS_MODIFY;
290
291 /* both times implies a utime(s) call */
292 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
293 mask |= FS_ATTRIB;
294 else if (ia_valid & ATTR_ATIME)
295 mask |= FS_ACCESS;
296 else if (ia_valid & ATTR_MTIME)
297 mask |= FS_MODIFY;
298
299 if (ia_valid & ATTR_MODE)
300 mask |= FS_ATTRIB;
301
302 if (mask) {
303 if (S_ISDIR(inode->i_mode))
304 mask |= FS_ISDIR;
305
306 fsnotify_parent(NULL, dentry, mask);
307 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
308 }
309}
310
311#if defined(CONFIG_FSNOTIFY) /* notify helpers */
312
313/*
314 * fsnotify_oldname_init - save off the old filename before we change it
315 */
316static inline const unsigned char *fsnotify_oldname_init(const unsigned char *name)
317{
318 return kstrdup(name, GFP_KERNEL);
319}
320
321/*
322 * fsnotify_oldname_free - free the name we got from fsnotify_oldname_init
323 */
324static inline void fsnotify_oldname_free(const unsigned char *old_name)
325{
326 kfree(old_name);
327}
328
329#else /* CONFIG_FSNOTIFY */
330
331static inline const char *fsnotify_oldname_init(const unsigned char *name)
332{
333 return NULL;
334}
335
336static inline void fsnotify_oldname_free(const unsigned char *old_name)
337{
338}
339
340#endif /* CONFIG_FSNOTIFY */
341
342#endif /* _LINUX_FS_NOTIFY_H */