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7#ifndef __LINUX_FSNOTIFY_BACKEND_H
8#define __LINUX_FSNOTIFY_BACKEND_H
9
10#ifdef __KERNEL__
11
12#include <linux/idr.h>
13#include <linux/fs.h>
14#include <linux/list.h>
15#include <linux/path.h>
16#include <linux/spinlock.h>
17#include <linux/types.h>
18#include <linux/atomic.h>
19#include <linux/user_namespace.h>
20
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25
26
27#define FS_ACCESS 0x00000001
28#define FS_MODIFY 0x00000002
29#define FS_ATTRIB 0x00000004
30#define FS_CLOSE_WRITE 0x00000008
31#define FS_CLOSE_NOWRITE 0x00000010
32#define FS_OPEN 0x00000020
33#define FS_MOVED_FROM 0x00000040
34#define FS_MOVED_TO 0x00000080
35#define FS_CREATE 0x00000100
36#define FS_DELETE 0x00000200
37#define FS_DELETE_SELF 0x00000400
38#define FS_MOVE_SELF 0x00000800
39
40#define FS_UNMOUNT 0x00002000
41#define FS_Q_OVERFLOW 0x00004000
42#define FS_IN_IGNORED 0x00008000
43
44#define FS_OPEN_PERM 0x00010000
45#define FS_ACCESS_PERM 0x00020000
46
47#define FS_EXCL_UNLINK 0x04000000
48#define FS_ISDIR 0x40000000
49#define FS_IN_ONESHOT 0x80000000
50
51#define FS_DN_RENAME 0x10000000
52#define FS_DN_MULTISHOT 0x20000000
53
54
55
56#define FS_EVENT_ON_CHILD 0x08000000
57
58
59
60#define FS_EVENTS_POSS_ON_CHILD (FS_ACCESS | FS_MODIFY | FS_ATTRIB |\
61 FS_CLOSE_WRITE | FS_CLOSE_NOWRITE | FS_OPEN |\
62 FS_MOVED_FROM | FS_MOVED_TO | FS_CREATE |\
63 FS_DELETE | FS_OPEN_PERM | FS_ACCESS_PERM)
64
65#define FS_MOVE (FS_MOVED_FROM | FS_MOVED_TO)
66
67#define ALL_FSNOTIFY_PERM_EVENTS (FS_OPEN_PERM | FS_ACCESS_PERM)
68
69#define ALL_FSNOTIFY_EVENTS (FS_ACCESS | FS_MODIFY | FS_ATTRIB | \
70 FS_CLOSE_WRITE | FS_CLOSE_NOWRITE | FS_OPEN | \
71 FS_MOVED_FROM | FS_MOVED_TO | FS_CREATE | \
72 FS_DELETE | FS_DELETE_SELF | FS_MOVE_SELF | \
73 FS_UNMOUNT | FS_Q_OVERFLOW | FS_IN_IGNORED | \
74 FS_OPEN_PERM | FS_ACCESS_PERM | FS_EXCL_UNLINK | \
75 FS_ISDIR | FS_IN_ONESHOT | FS_DN_RENAME | \
76 FS_DN_MULTISHOT | FS_EVENT_ON_CHILD)
77
78struct fsnotify_group;
79struct fsnotify_event;
80struct fsnotify_mark;
81struct fsnotify_event_private_data;
82struct fsnotify_fname;
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94
95struct fsnotify_ops {
96 int (*handle_event)(struct fsnotify_group *group,
97 struct inode *inode,
98 struct fsnotify_mark *inode_mark,
99 struct fsnotify_mark *vfsmount_mark,
100 u32 mask, const void *data, int data_type,
101 const unsigned char *file_name, u32 cookie);
102 void (*free_group_priv)(struct fsnotify_group *group);
103 void (*freeing_mark)(struct fsnotify_mark *mark, struct fsnotify_group *group);
104 void (*free_event)(struct fsnotify_event *event);
105};
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111
112struct fsnotify_event {
113 struct list_head list;
114
115 struct inode *inode;
116 u32 mask;
117};
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124
125struct fsnotify_group {
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133
134 atomic_t refcnt;
135
136 const struct fsnotify_ops *ops;
137
138
139 spinlock_t notification_lock;
140 struct list_head notification_list;
141 wait_queue_head_t notification_waitq;
142 unsigned int q_len;
143 unsigned int max_events;
144
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146
147
148 #define FS_PRIO_0 0
149 #define FS_PRIO_1 1
150 #define FS_PRIO_2 2
151 unsigned int priority;
152 bool shutdown;
153
154
155 struct mutex mark_mutex;
156 atomic_t num_marks;
157
158
159 struct list_head marks_list;
160
161 struct fasync_struct *fsn_fa;
162
163 struct fsnotify_event *overflow_event;
164
165
166
167
168 union {
169 void *private;
170#ifdef CONFIG_INOTIFY_USER
171 struct inotify_group_private_data {
172 spinlock_t idr_lock;
173 struct idr idr;
174 struct ucounts *ucounts;
175 } inotify_data;
176#endif
177#ifdef CONFIG_FANOTIFY
178 struct fanotify_group_private_data {
179#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
180
181 struct list_head access_list;
182 wait_queue_head_t access_waitq;
183#endif
184 int f_flags;
185 unsigned int max_marks;
186 struct user_struct *user;
187 } fanotify_data;
188#endif
189 };
190};
191
192
193#define FSNOTIFY_EVENT_NONE 0
194#define FSNOTIFY_EVENT_PATH 1
195#define FSNOTIFY_EVENT_INODE 2
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210
211struct fsnotify_mark {
212
213 __u32 mask;
214
215
216 atomic_t refcnt;
217
218
219 struct fsnotify_group *group;
220
221
222
223 struct list_head g_list;
224
225 spinlock_t lock;
226
227 struct hlist_node obj_list;
228 union {
229 struct inode *inode;
230 struct vfsmount *mnt;
231 };
232
233 __u32 ignored_mask;
234#define FSNOTIFY_MARK_FLAG_INODE 0x01
235#define FSNOTIFY_MARK_FLAG_VFSMOUNT 0x02
236#define FSNOTIFY_MARK_FLAG_OBJECT_PINNED 0x04
237#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x08
238#define FSNOTIFY_MARK_FLAG_ALIVE 0x10
239#define FSNOTIFY_MARK_FLAG_ATTACHED 0x20
240 unsigned int flags;
241 void (*free_mark)(struct fsnotify_mark *mark);
242};
243
244#ifdef CONFIG_FSNOTIFY
245
246
247
248
249extern int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
250 const unsigned char *name, u32 cookie);
251extern int __fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask);
252extern void __fsnotify_inode_delete(struct inode *inode);
253extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt);
254extern u32 fsnotify_get_cookie(void);
255
256static inline int fsnotify_inode_watches_children(struct inode *inode)
257{
258
259 if (!(inode->i_fsnotify_mask & FS_EVENT_ON_CHILD))
260 return 0;
261
262
263 return inode->i_fsnotify_mask & FS_EVENTS_POSS_ON_CHILD;
264}
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269
270static inline void fsnotify_update_flags(struct dentry *dentry)
271{
272 assert_spin_locked(&dentry->d_lock);
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281 if (fsnotify_inode_watches_children(dentry->d_parent->d_inode))
282 dentry->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED;
283 else
284 dentry->d_flags &= ~DCACHE_FSNOTIFY_PARENT_WATCHED;
285}
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289
290extern struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops);
291
292extern void fsnotify_get_group(struct fsnotify_group *group);
293
294extern void fsnotify_put_group(struct fsnotify_group *group);
295
296extern void fsnotify_group_stop_queueing(struct fsnotify_group *group);
297
298extern void fsnotify_destroy_group(struct fsnotify_group *group);
299
300extern int fsnotify_fasync(int fd, struct file *file, int on);
301
302extern void fsnotify_destroy_event(struct fsnotify_group *group,
303 struct fsnotify_event *event);
304
305extern int fsnotify_add_event(struct fsnotify_group *group,
306 struct fsnotify_event *event,
307 int (*merge)(struct list_head *,
308 struct fsnotify_event *));
309
310extern bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group);
311
312extern struct fsnotify_event *fsnotify_peek_first_event(struct fsnotify_group *group);
313
314extern struct fsnotify_event *fsnotify_remove_first_event(struct fsnotify_group *group);
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318
319extern void fsnotify_recalc_vfsmount_mask(struct vfsmount *mnt);
320
321extern void fsnotify_recalc_inode_mask(struct inode *inode);
322extern void fsnotify_init_mark(struct fsnotify_mark *mark, void (*free_mark)(struct fsnotify_mark *mark));
323
324extern struct fsnotify_mark *fsnotify_find_inode_mark(struct fsnotify_group *group, struct inode *inode);
325
326extern struct fsnotify_mark *fsnotify_find_vfsmount_mark(struct fsnotify_group *group, struct vfsmount *mnt);
327
328extern void fsnotify_set_mark_ignored_mask_locked(struct fsnotify_mark *mark, __u32 mask);
329
330extern void fsnotify_set_mark_mask_locked(struct fsnotify_mark *mark, __u32 mask);
331
332extern int fsnotify_add_mark(struct fsnotify_mark *mark, struct fsnotify_group *group,
333 struct inode *inode, struct vfsmount *mnt, int allow_dups);
334extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark, struct fsnotify_group *group,
335 struct inode *inode, struct vfsmount *mnt, int allow_dups);
336
337extern void fsnotify_destroy_mark(struct fsnotify_mark *mark,
338 struct fsnotify_group *group);
339
340extern void fsnotify_detach_mark(struct fsnotify_mark *mark);
341
342extern void fsnotify_free_mark(struct fsnotify_mark *mark);
343
344extern void fsnotify_clear_vfsmount_marks_by_group(struct fsnotify_group *group);
345
346extern void fsnotify_clear_inode_marks_by_group(struct fsnotify_group *group);
347
348extern void fsnotify_clear_marks_by_group_flags(struct fsnotify_group *group, unsigned int flags);
349extern void fsnotify_get_mark(struct fsnotify_mark *mark);
350extern void fsnotify_put_mark(struct fsnotify_mark *mark);
351extern void fsnotify_unmount_inodes(struct super_block *sb);
352
353
354extern void fsnotify_init_event(struct fsnotify_event *event,
355 struct inode *to_tell, u32 mask);
356
357#else
358
359static inline int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
360 const unsigned char *name, u32 cookie)
361{
362 return 0;
363}
364
365static inline int __fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask)
366{
367 return 0;
368}
369
370static inline void __fsnotify_inode_delete(struct inode *inode)
371{}
372
373static inline void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
374{}
375
376static inline void fsnotify_update_flags(struct dentry *dentry)
377{}
378
379static inline u32 fsnotify_get_cookie(void)
380{
381 return 0;
382}
383
384static inline void fsnotify_unmount_inodes(struct super_block *sb)
385{}
386
387#endif
388
389#endif
390
391#endif
392