2 * fs/inotify_user.c - inotify support for userspace
5 * John McCutchan <ttb@tentacle.dhs.org>
6 * Robert Love <rml@novell.com>
8 * Copyright (C) 2005 John McCutchan
9 * Copyright 2006 Hewlett-Packard Development Company, L.P.
11 * Copyright (C) 2009 Eric Paris <Red Hat Inc>
12 * inotify was largely rewriten to make use of the fsnotify infrastructure
14 * This program is free software; you can redistribute it and/or modify it
15 * under the terms of the GNU General Public License as published by the
16 * Free Software Foundation; either version 2, or (at your option) any
19 * This program is distributed in the hope that it will be useful, but
20 * WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 * General Public License for more details.
25 #include <linux/file.h>
26 #include <linux/fs.h> /* struct inode */
27 #include <linux/fsnotify_backend.h>
28 #include <linux/idr.h>
29 #include <linux/init.h> /* module_init */
30 #include <linux/inotify.h>
31 #include <linux/kernel.h> /* roundup() */
32 #include <linux/namei.h> /* LOOKUP_FOLLOW */
33 #include <linux/sched.h> /* struct user */
34 #include <linux/slab.h> /* struct kmem_cache */
35 #include <linux/syscalls.h>
36 #include <linux/types.h>
37 #include <linux/anon_inodes.h>
38 #include <linux/uaccess.h>
39 #include <linux/poll.h>
40 #include <linux/wait.h>
43 #include "../fdinfo.h"
45 #include <asm/ioctls.h>
47 /* these are configurable via /proc/sys/fs/inotify/ */
48 static int inotify_max_user_instances __read_mostly
;
49 static int inotify_max_queued_events __read_mostly
;
50 static int inotify_max_user_watches __read_mostly
;
52 static struct kmem_cache
*inotify_inode_mark_cachep __read_mostly
;
53 struct kmem_cache
*event_priv_cachep __read_mostly
;
57 #include <linux/sysctl.h>
61 ctl_table inotify_table
[] = {
63 .procname
= "max_user_instances",
64 .data
= &inotify_max_user_instances
,
65 .maxlen
= sizeof(int),
67 .proc_handler
= proc_dointvec_minmax
,
71 .procname
= "max_user_watches",
72 .data
= &inotify_max_user_watches
,
73 .maxlen
= sizeof(int),
75 .proc_handler
= proc_dointvec_minmax
,
79 .procname
= "max_queued_events",
80 .data
= &inotify_max_queued_events
,
81 .maxlen
= sizeof(int),
83 .proc_handler
= proc_dointvec_minmax
,
88 #endif /* CONFIG_SYSCTL */
90 static inline __u32
inotify_arg_to_mask(u32 arg
)
95 * everything should accept their own ignored, cares about children,
96 * and should receive events when the inode is unmounted
98 mask
= (FS_IN_IGNORED
| FS_EVENT_ON_CHILD
| FS_UNMOUNT
);
100 /* mask off the flags used to open the fd */
101 mask
|= (arg
& (IN_ALL_EVENTS
| IN_ONESHOT
| IN_EXCL_UNLINK
));
106 static inline u32
inotify_mask_to_arg(__u32 mask
)
108 return mask
& (IN_ALL_EVENTS
| IN_ISDIR
| IN_UNMOUNT
| IN_IGNORED
|
112 /* intofiy userspace file descriptor functions */
113 static unsigned int inotify_poll(struct file
*file
, poll_table
*wait
)
115 struct fsnotify_group
*group
= file
->private_data
;
118 poll_wait(file
, &group
->notification_waitq
, wait
);
119 mutex_lock(&group
->notification_mutex
);
120 if (!fsnotify_notify_queue_is_empty(group
))
121 ret
= POLLIN
| POLLRDNORM
;
122 mutex_unlock(&group
->notification_mutex
);
128 * Get an inotify_kernel_event if one exists and is small
129 * enough to fit in "count". Return an error pointer if
132 * Called with the group->notification_mutex held.
134 static struct fsnotify_event
*get_one_event(struct fsnotify_group
*group
,
137 size_t event_size
= sizeof(struct inotify_event
);
138 struct fsnotify_event
*event
;
140 if (fsnotify_notify_queue_is_empty(group
))
143 event
= fsnotify_peek_notify_event(group
);
145 pr_debug("%s: group=%p event=%p\n", __func__
, group
, event
);
148 event_size
+= roundup(event
->name_len
+ 1, event_size
);
150 if (event_size
> count
)
151 return ERR_PTR(-EINVAL
);
153 /* held the notification_mutex the whole time, so this is the
154 * same event we peeked above */
155 fsnotify_remove_notify_event(group
);
161 * Copy an event to user space, returning how much we copied.
163 * We already checked that the event size is smaller than the
164 * buffer we had in "get_one_event()" above.
166 static ssize_t
copy_event_to_user(struct fsnotify_group
*group
,
167 struct fsnotify_event
*event
,
170 struct inotify_event inotify_event
;
171 struct fsnotify_event_private_data
*fsn_priv
;
172 struct inotify_event_private_data
*priv
;
173 size_t event_size
= sizeof(struct inotify_event
);
176 pr_debug("%s: group=%p event=%p\n", __func__
, group
, event
);
178 /* we get the inotify watch descriptor from the event private data */
179 spin_lock(&event
->lock
);
180 fsn_priv
= fsnotify_remove_priv_from_event(group
, event
);
181 spin_unlock(&event
->lock
);
184 inotify_event
.wd
= -1;
186 priv
= container_of(fsn_priv
, struct inotify_event_private_data
,
187 fsnotify_event_priv_data
);
188 inotify_event
.wd
= priv
->wd
;
189 inotify_free_event_priv(fsn_priv
);
193 * round up event->name_len so it is a multiple of event_size
194 * plus an extra byte for the terminating '\0'.
197 name_len
= roundup(event
->name_len
+ 1, event_size
);
198 inotify_event
.len
= name_len
;
200 inotify_event
.mask
= inotify_mask_to_arg(event
->mask
);
201 inotify_event
.cookie
= event
->sync_cookie
;
203 /* send the main event */
204 if (copy_to_user(buf
, &inotify_event
, event_size
))
210 * fsnotify only stores the pathname, so here we have to send the pathname
211 * and then pad that pathname out to a multiple of sizeof(inotify_event)
212 * with zeros. I get my zeros from the nul_inotify_event.
215 unsigned int len_to_zero
= name_len
- event
->name_len
;
216 /* copy the path name */
217 if (copy_to_user(buf
, event
->file_name
, event
->name_len
))
219 buf
+= event
->name_len
;
221 /* fill userspace with 0's */
222 if (clear_user(buf
, len_to_zero
))
225 event_size
+= name_len
;
231 static ssize_t
inotify_read(struct file
*file
, char __user
*buf
,
232 size_t count
, loff_t
*pos
)
234 struct fsnotify_group
*group
;
235 struct fsnotify_event
*kevent
;
241 group
= file
->private_data
;
244 prepare_to_wait(&group
->notification_waitq
, &wait
, TASK_INTERRUPTIBLE
);
246 mutex_lock(&group
->notification_mutex
);
247 kevent
= get_one_event(group
, count
);
248 mutex_unlock(&group
->notification_mutex
);
250 pr_debug("%s: group=%p kevent=%p\n", __func__
, group
, kevent
);
253 ret
= PTR_ERR(kevent
);
256 ret
= copy_event_to_user(group
, kevent
, buf
);
257 fsnotify_put_event(kevent
);
266 if (file
->f_flags
& O_NONBLOCK
)
269 if (signal_pending(current
))
278 finish_wait(&group
->notification_waitq
, &wait
);
279 if (start
!= buf
&& ret
!= -EFAULT
)
284 static int inotify_release(struct inode
*ignored
, struct file
*file
)
286 struct fsnotify_group
*group
= file
->private_data
;
288 pr_debug("%s: group=%p\n", __func__
, group
);
290 if (file
->f_flags
& FASYNC
)
291 fsnotify_fasync(-1, file
, 0);
293 /* free this group, matching get was inotify_init->fsnotify_obtain_group */
294 fsnotify_destroy_group(group
);
299 static long inotify_ioctl(struct file
*file
, unsigned int cmd
,
302 struct fsnotify_group
*group
;
303 struct fsnotify_event_holder
*holder
;
304 struct fsnotify_event
*event
;
309 group
= file
->private_data
;
310 p
= (void __user
*) arg
;
312 pr_debug("%s: group=%p cmd=%u\n", __func__
, group
, cmd
);
316 mutex_lock(&group
->notification_mutex
);
317 list_for_each_entry(holder
, &group
->notification_list
, event_list
) {
318 event
= holder
->event
;
319 send_len
+= sizeof(struct inotify_event
);
321 send_len
+= roundup(event
->name_len
+ 1,
322 sizeof(struct inotify_event
));
324 mutex_unlock(&group
->notification_mutex
);
325 ret
= put_user(send_len
, (int __user
*) p
);
332 static const struct file_operations inotify_fops
= {
333 .show_fdinfo
= inotify_show_fdinfo
,
334 .poll
= inotify_poll
,
335 .read
= inotify_read
,
336 .fasync
= fsnotify_fasync
,
337 .release
= inotify_release
,
338 .unlocked_ioctl
= inotify_ioctl
,
339 .compat_ioctl
= inotify_ioctl
,
340 .llseek
= noop_llseek
,
345 * find_inode - resolve a user-given path to a specific inode
347 static int inotify_find_inode(const char __user
*dirname
, struct path
*path
, unsigned flags
)
351 error
= user_path_at(AT_FDCWD
, dirname
, flags
, path
);
354 /* you can only watch an inode if you have read permissions on it */
355 error
= inode_permission(path
->dentry
->d_inode
, MAY_READ
);
361 static int inotify_add_to_idr(struct idr
*idr
, spinlock_t
*idr_lock
,
363 struct inotify_inode_mark
*i_mark
)
368 if (unlikely(!idr_pre_get(idr
, GFP_KERNEL
)))
372 ret
= idr_get_new_above(idr
, i_mark
, *last_wd
+ 1,
374 /* we added the mark to the idr, take a reference */
376 *last_wd
= i_mark
->wd
;
377 fsnotify_get_mark(&i_mark
->fsn_mark
);
379 spin_unlock(idr_lock
);
380 } while (ret
== -EAGAIN
);
385 static struct inotify_inode_mark
*inotify_idr_find_locked(struct fsnotify_group
*group
,
388 struct idr
*idr
= &group
->inotify_data
.idr
;
389 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
390 struct inotify_inode_mark
*i_mark
;
392 assert_spin_locked(idr_lock
);
394 i_mark
= idr_find(idr
, wd
);
396 struct fsnotify_mark
*fsn_mark
= &i_mark
->fsn_mark
;
398 fsnotify_get_mark(fsn_mark
);
399 /* One ref for being in the idr, one ref we just took */
400 BUG_ON(atomic_read(&fsn_mark
->refcnt
) < 2);
406 static struct inotify_inode_mark
*inotify_idr_find(struct fsnotify_group
*group
,
409 struct inotify_inode_mark
*i_mark
;
410 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
413 i_mark
= inotify_idr_find_locked(group
, wd
);
414 spin_unlock(idr_lock
);
419 static void do_inotify_remove_from_idr(struct fsnotify_group
*group
,
420 struct inotify_inode_mark
*i_mark
)
422 struct idr
*idr
= &group
->inotify_data
.idr
;
423 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
426 assert_spin_locked(idr_lock
);
430 /* removed from the idr, drop that ref */
431 fsnotify_put_mark(&i_mark
->fsn_mark
);
435 * Remove the mark from the idr (if present) and drop the reference
436 * on the mark because it was in the idr.
438 static void inotify_remove_from_idr(struct fsnotify_group
*group
,
439 struct inotify_inode_mark
*i_mark
)
441 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
442 struct inotify_inode_mark
*found_i_mark
= NULL
;
449 * does this i_mark think it is in the idr? we shouldn't get called
453 WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p"
454 " i_mark->inode=%p\n", __func__
, i_mark
, i_mark
->wd
,
455 i_mark
->fsn_mark
.group
, i_mark
->fsn_mark
.i
.inode
);
459 /* Lets look in the idr to see if we find it */
460 found_i_mark
= inotify_idr_find_locked(group
, wd
);
461 if (unlikely(!found_i_mark
)) {
462 WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p"
463 " i_mark->inode=%p\n", __func__
, i_mark
, i_mark
->wd
,
464 i_mark
->fsn_mark
.group
, i_mark
->fsn_mark
.i
.inode
);
469 * We found an mark in the idr at the right wd, but it's
470 * not the mark we were told to remove. eparis seriously
471 * fucked up somewhere.
473 if (unlikely(found_i_mark
!= i_mark
)) {
474 WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p "
475 "mark->inode=%p found_i_mark=%p found_i_mark->wd=%d "
476 "found_i_mark->group=%p found_i_mark->inode=%p\n",
477 __func__
, i_mark
, i_mark
->wd
, i_mark
->fsn_mark
.group
,
478 i_mark
->fsn_mark
.i
.inode
, found_i_mark
, found_i_mark
->wd
,
479 found_i_mark
->fsn_mark
.group
,
480 found_i_mark
->fsn_mark
.i
.inode
);
485 * One ref for being in the idr
486 * one ref held by the caller trying to kill us
487 * one ref grabbed by inotify_idr_find
489 if (unlikely(atomic_read(&i_mark
->fsn_mark
.refcnt
) < 3)) {
490 printk(KERN_ERR
"%s: i_mark=%p i_mark->wd=%d i_mark->group=%p"
491 " i_mark->inode=%p\n", __func__
, i_mark
, i_mark
->wd
,
492 i_mark
->fsn_mark
.group
, i_mark
->fsn_mark
.i
.inode
);
493 /* we can't really recover with bad ref cnting.. */
497 do_inotify_remove_from_idr(group
, i_mark
);
499 /* match the ref taken by inotify_idr_find_locked() */
501 fsnotify_put_mark(&found_i_mark
->fsn_mark
);
503 spin_unlock(idr_lock
);
507 * Send IN_IGNORED for this wd, remove this wd from the idr.
509 void inotify_ignored_and_remove_idr(struct fsnotify_mark
*fsn_mark
,
510 struct fsnotify_group
*group
)
512 struct inotify_inode_mark
*i_mark
;
513 struct fsnotify_event
*ignored_event
, *notify_event
;
514 struct inotify_event_private_data
*event_priv
;
515 struct fsnotify_event_private_data
*fsn_event_priv
;
518 i_mark
= container_of(fsn_mark
, struct inotify_inode_mark
, fsn_mark
);
520 ignored_event
= fsnotify_create_event(NULL
, FS_IN_IGNORED
, NULL
,
521 FSNOTIFY_EVENT_NONE
, NULL
, 0,
524 goto skip_send_ignore
;
526 event_priv
= kmem_cache_alloc(event_priv_cachep
, GFP_NOFS
);
527 if (unlikely(!event_priv
))
528 goto skip_send_ignore
;
530 fsn_event_priv
= &event_priv
->fsnotify_event_priv_data
;
532 fsnotify_get_group(group
);
533 fsn_event_priv
->group
= group
;
534 event_priv
->wd
= i_mark
->wd
;
536 notify_event
= fsnotify_add_notify_event(group
, ignored_event
, fsn_event_priv
, NULL
);
538 if (IS_ERR(notify_event
))
539 ret
= PTR_ERR(notify_event
);
541 fsnotify_put_event(notify_event
);
542 inotify_free_event_priv(fsn_event_priv
);
546 /* matches the reference taken when the event was created */
548 fsnotify_put_event(ignored_event
);
550 /* remove this mark from the idr */
551 inotify_remove_from_idr(group
, i_mark
);
553 atomic_dec(&group
->inotify_data
.user
->inotify_watches
);
556 /* ding dong the mark is dead */
557 static void inotify_free_mark(struct fsnotify_mark
*fsn_mark
)
559 struct inotify_inode_mark
*i_mark
;
561 i_mark
= container_of(fsn_mark
, struct inotify_inode_mark
, fsn_mark
);
563 kmem_cache_free(inotify_inode_mark_cachep
, i_mark
);
566 static int inotify_update_existing_watch(struct fsnotify_group
*group
,
570 struct fsnotify_mark
*fsn_mark
;
571 struct inotify_inode_mark
*i_mark
;
572 __u32 old_mask
, new_mask
;
574 int add
= (arg
& IN_MASK_ADD
);
577 /* don't allow invalid bits: we don't want flags set */
578 mask
= inotify_arg_to_mask(arg
);
579 if (unlikely(!(mask
& IN_ALL_EVENTS
)))
582 fsn_mark
= fsnotify_find_inode_mark(group
, inode
);
586 i_mark
= container_of(fsn_mark
, struct inotify_inode_mark
, fsn_mark
);
588 spin_lock(&fsn_mark
->lock
);
590 old_mask
= fsn_mark
->mask
;
592 fsnotify_set_mark_mask_locked(fsn_mark
, (fsn_mark
->mask
| mask
));
594 fsnotify_set_mark_mask_locked(fsn_mark
, mask
);
595 new_mask
= fsn_mark
->mask
;
597 spin_unlock(&fsn_mark
->lock
);
599 if (old_mask
!= new_mask
) {
600 /* more bits in old than in new? */
601 int dropped
= (old_mask
& ~new_mask
);
602 /* more bits in this fsn_mark than the inode's mask? */
603 int do_inode
= (new_mask
& ~inode
->i_fsnotify_mask
);
605 /* update the inode with this new fsn_mark */
606 if (dropped
|| do_inode
)
607 fsnotify_recalc_inode_mask(inode
);
614 /* match the get from fsnotify_find_mark() */
615 fsnotify_put_mark(fsn_mark
);
620 static int inotify_new_watch(struct fsnotify_group
*group
,
624 struct inotify_inode_mark
*tmp_i_mark
;
627 struct idr
*idr
= &group
->inotify_data
.idr
;
628 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
630 /* don't allow invalid bits: we don't want flags set */
631 mask
= inotify_arg_to_mask(arg
);
632 if (unlikely(!(mask
& IN_ALL_EVENTS
)))
635 tmp_i_mark
= kmem_cache_alloc(inotify_inode_mark_cachep
, GFP_KERNEL
);
636 if (unlikely(!tmp_i_mark
))
639 fsnotify_init_mark(&tmp_i_mark
->fsn_mark
, inotify_free_mark
);
640 tmp_i_mark
->fsn_mark
.mask
= mask
;
644 if (atomic_read(&group
->inotify_data
.user
->inotify_watches
) >= inotify_max_user_watches
)
647 ret
= inotify_add_to_idr(idr
, idr_lock
, &group
->inotify_data
.last_wd
,
652 /* we are on the idr, now get on the inode */
653 ret
= fsnotify_add_mark(&tmp_i_mark
->fsn_mark
, group
, inode
, NULL
, 0);
655 /* we failed to get on the inode, get off the idr */
656 inotify_remove_from_idr(group
, tmp_i_mark
);
660 /* increment the number of watches the user has */
661 atomic_inc(&group
->inotify_data
.user
->inotify_watches
);
663 /* return the watch descriptor for this new mark */
664 ret
= tmp_i_mark
->wd
;
667 /* match the ref from fsnotify_init_mark() */
668 fsnotify_put_mark(&tmp_i_mark
->fsn_mark
);
673 static int inotify_update_watch(struct fsnotify_group
*group
, struct inode
*inode
, u32 arg
)
678 /* try to update and existing watch with the new arg */
679 ret
= inotify_update_existing_watch(group
, inode
, arg
);
680 /* no mark present, try to add a new one */
682 ret
= inotify_new_watch(group
, inode
, arg
);
684 * inotify_new_watch could race with another thread which did an
685 * inotify_new_watch between the update_existing and the add watch
686 * here, go back and try to update an existing mark again.
694 static struct fsnotify_group
*inotify_new_group(unsigned int max_events
)
696 struct fsnotify_group
*group
;
698 group
= fsnotify_alloc_group(&inotify_fsnotify_ops
);
702 group
->max_events
= max_events
;
704 spin_lock_init(&group
->inotify_data
.idr_lock
);
705 idr_init(&group
->inotify_data
.idr
);
706 group
->inotify_data
.last_wd
= 0;
707 group
->inotify_data
.user
= get_current_user();
709 if (atomic_inc_return(&group
->inotify_data
.user
->inotify_devs
) >
710 inotify_max_user_instances
) {
711 fsnotify_destroy_group(group
);
712 return ERR_PTR(-EMFILE
);
719 /* inotify syscalls */
720 SYSCALL_DEFINE1(inotify_init1
, int, flags
)
722 struct fsnotify_group
*group
;
725 /* Check the IN_* constants for consistency. */
726 BUILD_BUG_ON(IN_CLOEXEC
!= O_CLOEXEC
);
727 BUILD_BUG_ON(IN_NONBLOCK
!= O_NONBLOCK
);
729 if (flags
& ~(IN_CLOEXEC
| IN_NONBLOCK
))
732 /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */
733 group
= inotify_new_group(inotify_max_queued_events
);
735 return PTR_ERR(group
);
737 ret
= anon_inode_getfd("inotify", &inotify_fops
, group
,
740 fsnotify_destroy_group(group
);
745 SYSCALL_DEFINE0(inotify_init
)
747 return sys_inotify_init1(0);
750 SYSCALL_DEFINE3(inotify_add_watch
, int, fd
, const char __user
*, pathname
,
753 struct fsnotify_group
*group
;
761 if (unlikely(!f
.file
))
764 /* verify that this is indeed an inotify instance */
765 if (unlikely(f
.file
->f_op
!= &inotify_fops
)) {
770 if (!(mask
& IN_DONT_FOLLOW
))
771 flags
|= LOOKUP_FOLLOW
;
772 if (mask
& IN_ONLYDIR
)
773 flags
|= LOOKUP_DIRECTORY
;
775 ret
= inotify_find_inode(pathname
, &path
, flags
);
779 /* inode held in place by reference to path; group by fget on fd */
780 inode
= path
.dentry
->d_inode
;
781 group
= f
.file
->private_data
;
783 /* create/update an inode mark */
784 ret
= inotify_update_watch(group
, inode
, mask
);
791 SYSCALL_DEFINE2(inotify_rm_watch
, int, fd
, __s32
, wd
)
793 struct fsnotify_group
*group
;
794 struct inotify_inode_mark
*i_mark
;
799 if (unlikely(!f
.file
))
802 /* verify that this is indeed an inotify instance */
804 if (unlikely(f
.file
->f_op
!= &inotify_fops
))
807 group
= f
.file
->private_data
;
810 i_mark
= inotify_idr_find(group
, wd
);
811 if (unlikely(!i_mark
))
816 fsnotify_destroy_mark(&i_mark
->fsn_mark
, group
);
818 /* match ref taken by inotify_idr_find */
819 fsnotify_put_mark(&i_mark
->fsn_mark
);
827 * inotify_user_setup - Our initialization function. Note that we cannot return
828 * error because we have compiled-in VFS hooks. So an (unlikely) failure here
829 * must result in panic().
831 static int __init
inotify_user_setup(void)
833 BUILD_BUG_ON(IN_ACCESS
!= FS_ACCESS
);
834 BUILD_BUG_ON(IN_MODIFY
!= FS_MODIFY
);
835 BUILD_BUG_ON(IN_ATTRIB
!= FS_ATTRIB
);
836 BUILD_BUG_ON(IN_CLOSE_WRITE
!= FS_CLOSE_WRITE
);
837 BUILD_BUG_ON(IN_CLOSE_NOWRITE
!= FS_CLOSE_NOWRITE
);
838 BUILD_BUG_ON(IN_OPEN
!= FS_OPEN
);
839 BUILD_BUG_ON(IN_MOVED_FROM
!= FS_MOVED_FROM
);
840 BUILD_BUG_ON(IN_MOVED_TO
!= FS_MOVED_TO
);
841 BUILD_BUG_ON(IN_CREATE
!= FS_CREATE
);
842 BUILD_BUG_ON(IN_DELETE
!= FS_DELETE
);
843 BUILD_BUG_ON(IN_DELETE_SELF
!= FS_DELETE_SELF
);
844 BUILD_BUG_ON(IN_MOVE_SELF
!= FS_MOVE_SELF
);
845 BUILD_BUG_ON(IN_UNMOUNT
!= FS_UNMOUNT
);
846 BUILD_BUG_ON(IN_Q_OVERFLOW
!= FS_Q_OVERFLOW
);
847 BUILD_BUG_ON(IN_IGNORED
!= FS_IN_IGNORED
);
848 BUILD_BUG_ON(IN_EXCL_UNLINK
!= FS_EXCL_UNLINK
);
849 BUILD_BUG_ON(IN_ISDIR
!= FS_ISDIR
);
850 BUILD_BUG_ON(IN_ONESHOT
!= FS_IN_ONESHOT
);
852 BUG_ON(hweight32(ALL_INOTIFY_BITS
) != 21);
854 inotify_inode_mark_cachep
= KMEM_CACHE(inotify_inode_mark
, SLAB_PANIC
);
855 event_priv_cachep
= KMEM_CACHE(inotify_event_private_data
, SLAB_PANIC
);
857 inotify_max_queued_events
= 16384;
858 inotify_max_user_instances
= 128;
859 inotify_max_user_watches
= 8192;
863 module_init(inotify_user_setup
);