Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_FS_NOTIFY_H
3#define _LINUX_FS_NOTIFY_H
4
5/*
6 * include/linux/fsnotify.h - generic hooks for filesystem notification, to
7 * reduce in-source duplication from both dnotify and inotify.
8 *
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.
11 *
12 * (C) Copyright 2005 Robert Love
13 */
14
15#include <linux/fsnotify_backend.h>
16#include <linux/audit.h>
17#include <linux/slab.h>
18#include <linux/bug.h>
19
20/* Notify this dentry's parent about a child's events. */
21static inline int fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask)
22{
23 if (!dentry)
24 dentry = path->dentry;
25
26 return __fsnotify_parent(path, dentry, mask);
27}
28
29/* simple call site for access decisions */
30static inline int fsnotify_perm(struct file *file, int mask)
31{
32 const struct path *path = &file->f_path;
33 struct inode *inode = file_inode(file);
34 __u32 fsnotify_mask = 0;
35 int ret;
36
37 if (file->f_mode & FMODE_NONOTIFY)
38 return 0;
39 if (!(mask & (MAY_READ | MAY_OPEN)))
40 return 0;
41 if (mask & MAY_OPEN)
42 fsnotify_mask = FS_OPEN_PERM;
43 else if (mask & MAY_READ)
44 fsnotify_mask = FS_ACCESS_PERM;
45 else
46 BUG();
47
48 ret = fsnotify_parent(path, NULL, fsnotify_mask);
49 if (ret)
50 return ret;
51
52 return fsnotify(inode, fsnotify_mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
53}
54
55/*
56 * fsnotify_link_count - inode's link count changed
57 */
58static inline void fsnotify_link_count(struct inode *inode)
59{
60 fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
61}
62
63/*
64 * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
65 */
66static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
67 const unsigned char *old_name,
68 int isdir, struct inode *target, struct dentry *moved)
69{
70 struct inode *source = moved->d_inode;
71 u32 fs_cookie = fsnotify_get_cookie();
72 __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM);
73 __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO);
74 const unsigned char *new_name = moved->d_name.name;
75
76 if (old_dir == new_dir)
77 old_dir_mask |= FS_DN_RENAME;
78
79 if (isdir) {
80 old_dir_mask |= FS_ISDIR;
81 new_dir_mask |= FS_ISDIR;
82 }
83
84 fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name,
85 fs_cookie);
86 fsnotify(new_dir, new_dir_mask, source, FSNOTIFY_EVENT_INODE, new_name,
87 fs_cookie);
88
89 if (target)
90 fsnotify_link_count(target);
91
92 if (source)
93 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0);
94 audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE);
95}
96
97/*
98 * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
99 */
100static inline void fsnotify_inode_delete(struct inode *inode)
101{
102 __fsnotify_inode_delete(inode);
103}
104
105/*
106 * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
107 */
108static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
109{
110 __fsnotify_vfsmount_delete(mnt);
111}
112
113/*
114 * fsnotify_nameremove - a filename was removed from a directory
115 */
116static inline void fsnotify_nameremove(struct dentry *dentry, int isdir)
117{
118 __u32 mask = FS_DELETE;
119
120 if (isdir)
121 mask |= FS_ISDIR;
122
123 fsnotify_parent(NULL, dentry, mask);
124}
125
126/*
127 * fsnotify_inoderemove - an inode is going away
128 */
129static inline void fsnotify_inoderemove(struct inode *inode)
130{
131 fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
132 __fsnotify_inode_delete(inode);
133}
134
135/*
136 * fsnotify_create - 'name' was linked in
137 */
138static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
139{
140 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);
141
142 fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
143}
144
145/*
146 * fsnotify_link - new hardlink in 'inode' directory
147 * Note: We have to pass also the linked inode ptr as some filesystems leave
148 * new_dentry->d_inode NULL and instantiate inode pointer later
149 */
150static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry)
151{
152 fsnotify_link_count(inode);
153 audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);
154
155 fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0);
156}
157
158/*
159 * fsnotify_mkdir - directory 'name' was created
160 */
161static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
162{
163 __u32 mask = (FS_CREATE | FS_ISDIR);
164 struct inode *d_inode = dentry->d_inode;
165
166 audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);
167
168 fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
169}
170
171/*
172 * fsnotify_access - file was read
173 */
174static inline void fsnotify_access(struct file *file)
175{
176 const struct path *path = &file->f_path;
177 struct inode *inode = file_inode(file);
178 __u32 mask = FS_ACCESS;
179
180 if (S_ISDIR(inode->i_mode))
181 mask |= FS_ISDIR;
182
183 if (!(file->f_mode & FMODE_NONOTIFY)) {
184 fsnotify_parent(path, NULL, mask);
185 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
186 }
187}
188
189/*
190 * fsnotify_modify - file was modified
191 */
192static inline void fsnotify_modify(struct file *file)
193{
194 const struct path *path = &file->f_path;
195 struct inode *inode = file_inode(file);
196 __u32 mask = FS_MODIFY;
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_open - file was opened
209 */
210static inline void fsnotify_open(struct file *file)
211{
212 const struct path *path = &file->f_path;
213 struct inode *inode = file_inode(file);
214 __u32 mask = FS_OPEN;
215
216 if (S_ISDIR(inode->i_mode))
217 mask |= FS_ISDIR;
218
219 fsnotify_parent(path, NULL, mask);
220 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
221}
222
223/*
224 * fsnotify_close - file was closed
225 */
226static inline void fsnotify_close(struct file *file)
227{
228 const struct path *path = &file->f_path;
229 struct inode *inode = file_inode(file);
230 fmode_t mode = file->f_mode;
231 __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE;
232
233 if (S_ISDIR(inode->i_mode))
234 mask |= FS_ISDIR;
235
236 if (!(file->f_mode & FMODE_NONOTIFY)) {
237 fsnotify_parent(path, NULL, mask);
238 fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
239 }
240}
241
242/*
243 * fsnotify_xattr - extended attributes were changed
244 */
245static inline void fsnotify_xattr(struct dentry *dentry)
246{
247 struct inode *inode = dentry->d_inode;
248 __u32 mask = FS_ATTRIB;
249
250 if (S_ISDIR(inode->i_mode))
251 mask |= FS_ISDIR;
252
253 fsnotify_parent(NULL, dentry, mask);
254 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
255}
256
257/*
258 * fsnotify_change - notify_change event. file was modified and/or metadata
259 * was changed.
260 */
261static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
262{
263 struct inode *inode = dentry->d_inode;
264 __u32 mask = 0;
265
266 if (ia_valid & ATTR_UID)
267 mask |= FS_ATTRIB;
268 if (ia_valid & ATTR_GID)
269 mask |= FS_ATTRIB;
270 if (ia_valid & ATTR_SIZE)
271 mask |= FS_MODIFY;
272
273 /* both times implies a utime(s) call */
274 if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
275 mask |= FS_ATTRIB;
276 else if (ia_valid & ATTR_ATIME)
277 mask |= FS_ACCESS;
278 else if (ia_valid & ATTR_MTIME)
279 mask |= FS_MODIFY;
280
281 if (ia_valid & ATTR_MODE)
282 mask |= FS_ATTRIB;
283
284 if (mask) {
285 if (S_ISDIR(inode->i_mode))
286 mask |= FS_ISDIR;
287
288 fsnotify_parent(NULL, dentry, mask);
289 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
290 }
291}
292
293#endif /* _LINUX_FS_NOTIFY_H */