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>
44 #include <asm/ioctls.h>
46 /* these are configurable via /proc/sys/fs/inotify/ */
47 static int inotify_max_user_instances __read_mostly
;
48 static int inotify_max_queued_events __read_mostly
;
49 static int inotify_max_user_watches __read_mostly
;
51 static struct kmem_cache
*inotify_inode_mark_cachep __read_mostly
;
52 struct kmem_cache
*event_priv_cachep __read_mostly
;
56 #include <linux/sysctl.h>
60 ctl_table inotify_table
[] = {
62 .procname
= "max_user_instances",
63 .data
= &inotify_max_user_instances
,
64 .maxlen
= sizeof(int),
66 .proc_handler
= proc_dointvec_minmax
,
70 .procname
= "max_user_watches",
71 .data
= &inotify_max_user_watches
,
72 .maxlen
= sizeof(int),
74 .proc_handler
= proc_dointvec_minmax
,
78 .procname
= "max_queued_events",
79 .data
= &inotify_max_queued_events
,
80 .maxlen
= sizeof(int),
82 .proc_handler
= proc_dointvec_minmax
,
87 #endif /* CONFIG_SYSCTL */
89 static inline __u32
inotify_arg_to_mask(u32 arg
)
94 * everything should accept their own ignored, cares about children,
95 * and should receive events when the inode is unmounted
97 mask
= (FS_IN_IGNORED
| FS_EVENT_ON_CHILD
| FS_UNMOUNT
);
99 /* mask off the flags used to open the fd */
100 mask
|= (arg
& (IN_ALL_EVENTS
| IN_ONESHOT
| IN_EXCL_UNLINK
));
105 static inline u32
inotify_mask_to_arg(__u32 mask
)
107 return mask
& (IN_ALL_EVENTS
| IN_ISDIR
| IN_UNMOUNT
| IN_IGNORED
|
111 /* intofiy userspace file descriptor functions */
112 static unsigned int inotify_poll(struct file
*file
, poll_table
*wait
)
114 struct fsnotify_group
*group
= file
->private_data
;
117 poll_wait(file
, &group
->notification_waitq
, wait
);
118 mutex_lock(&group
->notification_mutex
);
119 if (!fsnotify_notify_queue_is_empty(group
))
120 ret
= POLLIN
| POLLRDNORM
;
121 mutex_unlock(&group
->notification_mutex
);
127 * Get an inotify_kernel_event if one exists and is small
128 * enough to fit in "count". Return an error pointer if
131 * Called with the group->notification_mutex held.
133 static struct fsnotify_event
*get_one_event(struct fsnotify_group
*group
,
136 size_t event_size
= sizeof(struct inotify_event
);
137 struct fsnotify_event
*event
;
139 if (fsnotify_notify_queue_is_empty(group
))
142 event
= fsnotify_peek_notify_event(group
);
144 pr_debug("%s: group=%p event=%p\n", __func__
, group
, event
);
147 event_size
+= roundup(event
->name_len
+ 1, event_size
);
149 if (event_size
> count
)
150 return ERR_PTR(-EINVAL
);
152 /* held the notification_mutex the whole time, so this is the
153 * same event we peeked above */
154 fsnotify_remove_notify_event(group
);
160 * Copy an event to user space, returning how much we copied.
162 * We already checked that the event size is smaller than the
163 * buffer we had in "get_one_event()" above.
165 static ssize_t
copy_event_to_user(struct fsnotify_group
*group
,
166 struct fsnotify_event
*event
,
169 struct inotify_event inotify_event
;
170 struct fsnotify_event_private_data
*fsn_priv
;
171 struct inotify_event_private_data
*priv
;
172 size_t event_size
= sizeof(struct inotify_event
);
175 pr_debug("%s: group=%p event=%p\n", __func__
, group
, event
);
177 /* we get the inotify watch descriptor from the event private data */
178 spin_lock(&event
->lock
);
179 fsn_priv
= fsnotify_remove_priv_from_event(group
, event
);
180 spin_unlock(&event
->lock
);
183 inotify_event
.wd
= -1;
185 priv
= container_of(fsn_priv
, struct inotify_event_private_data
,
186 fsnotify_event_priv_data
);
187 inotify_event
.wd
= priv
->wd
;
188 inotify_free_event_priv(fsn_priv
);
192 * round up event->name_len so it is a multiple of event_size
193 * plus an extra byte for the terminating '\0'.
196 name_len
= roundup(event
->name_len
+ 1, event_size
);
197 inotify_event
.len
= name_len
;
199 inotify_event
.mask
= inotify_mask_to_arg(event
->mask
);
200 inotify_event
.cookie
= event
->sync_cookie
;
202 /* send the main event */
203 if (copy_to_user(buf
, &inotify_event
, event_size
))
209 * fsnotify only stores the pathname, so here we have to send the pathname
210 * and then pad that pathname out to a multiple of sizeof(inotify_event)
211 * with zeros. I get my zeros from the nul_inotify_event.
214 unsigned int len_to_zero
= name_len
- event
->name_len
;
215 /* copy the path name */
216 if (copy_to_user(buf
, event
->file_name
, event
->name_len
))
218 buf
+= event
->name_len
;
220 /* fill userspace with 0's */
221 if (clear_user(buf
, len_to_zero
))
224 event_size
+= name_len
;
230 static ssize_t
inotify_read(struct file
*file
, char __user
*buf
,
231 size_t count
, loff_t
*pos
)
233 struct fsnotify_group
*group
;
234 struct fsnotify_event
*kevent
;
240 group
= file
->private_data
;
243 prepare_to_wait(&group
->notification_waitq
, &wait
, TASK_INTERRUPTIBLE
);
245 mutex_lock(&group
->notification_mutex
);
246 kevent
= get_one_event(group
, count
);
247 mutex_unlock(&group
->notification_mutex
);
249 pr_debug("%s: group=%p kevent=%p\n", __func__
, group
, kevent
);
252 ret
= PTR_ERR(kevent
);
255 ret
= copy_event_to_user(group
, kevent
, buf
);
256 fsnotify_put_event(kevent
);
265 if (file
->f_flags
& O_NONBLOCK
)
268 if (signal_pending(current
))
277 finish_wait(&group
->notification_waitq
, &wait
);
278 if (start
!= buf
&& ret
!= -EFAULT
)
283 static int inotify_release(struct inode
*ignored
, struct file
*file
)
285 struct fsnotify_group
*group
= file
->private_data
;
287 pr_debug("%s: group=%p\n", __func__
, group
);
289 if (file
->f_flags
& FASYNC
)
290 fsnotify_fasync(-1, file
, 0);
292 /* free this group, matching get was inotify_init->fsnotify_obtain_group */
293 fsnotify_destroy_group(group
);
298 static long inotify_ioctl(struct file
*file
, unsigned int cmd
,
301 struct fsnotify_group
*group
;
302 struct fsnotify_event_holder
*holder
;
303 struct fsnotify_event
*event
;
308 group
= file
->private_data
;
309 p
= (void __user
*) arg
;
311 pr_debug("%s: group=%p cmd=%u\n", __func__
, group
, cmd
);
315 mutex_lock(&group
->notification_mutex
);
316 list_for_each_entry(holder
, &group
->notification_list
, event_list
) {
317 event
= holder
->event
;
318 send_len
+= sizeof(struct inotify_event
);
320 send_len
+= roundup(event
->name_len
+ 1,
321 sizeof(struct inotify_event
));
323 mutex_unlock(&group
->notification_mutex
);
324 ret
= put_user(send_len
, (int __user
*) p
);
331 static const struct file_operations inotify_fops
= {
332 .poll
= inotify_poll
,
333 .read
= inotify_read
,
334 .fasync
= fsnotify_fasync
,
335 .release
= inotify_release
,
336 .unlocked_ioctl
= inotify_ioctl
,
337 .compat_ioctl
= inotify_ioctl
,
338 .llseek
= noop_llseek
,
343 * find_inode - resolve a user-given path to a specific inode
345 static int inotify_find_inode(const char __user
*dirname
, struct path
*path
, unsigned flags
)
349 error
= user_path_at(AT_FDCWD
, dirname
, flags
, path
);
352 /* you can only watch an inode if you have read permissions on it */
353 error
= inode_permission(path
->dentry
->d_inode
, MAY_READ
);
359 static int inotify_add_to_idr(struct idr
*idr
, spinlock_t
*idr_lock
,
361 struct inotify_inode_mark
*i_mark
)
366 if (unlikely(!idr_pre_get(idr
, GFP_KERNEL
)))
370 ret
= idr_get_new_above(idr
, i_mark
, *last_wd
+ 1,
372 /* we added the mark to the idr, take a reference */
374 *last_wd
= i_mark
->wd
;
375 fsnotify_get_mark(&i_mark
->fsn_mark
);
377 spin_unlock(idr_lock
);
378 } while (ret
== -EAGAIN
);
383 static struct inotify_inode_mark
*inotify_idr_find_locked(struct fsnotify_group
*group
,
386 struct idr
*idr
= &group
->inotify_data
.idr
;
387 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
388 struct inotify_inode_mark
*i_mark
;
390 assert_spin_locked(idr_lock
);
392 i_mark
= idr_find(idr
, wd
);
394 struct fsnotify_mark
*fsn_mark
= &i_mark
->fsn_mark
;
396 fsnotify_get_mark(fsn_mark
);
397 /* One ref for being in the idr, one ref we just took */
398 BUG_ON(atomic_read(&fsn_mark
->refcnt
) < 2);
404 static struct inotify_inode_mark
*inotify_idr_find(struct fsnotify_group
*group
,
407 struct inotify_inode_mark
*i_mark
;
408 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
411 i_mark
= inotify_idr_find_locked(group
, wd
);
412 spin_unlock(idr_lock
);
417 static void do_inotify_remove_from_idr(struct fsnotify_group
*group
,
418 struct inotify_inode_mark
*i_mark
)
420 struct idr
*idr
= &group
->inotify_data
.idr
;
421 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
424 assert_spin_locked(idr_lock
);
428 /* removed from the idr, drop that ref */
429 fsnotify_put_mark(&i_mark
->fsn_mark
);
433 * Remove the mark from the idr (if present) and drop the reference
434 * on the mark because it was in the idr.
436 static void inotify_remove_from_idr(struct fsnotify_group
*group
,
437 struct inotify_inode_mark
*i_mark
)
439 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
440 struct inotify_inode_mark
*found_i_mark
= NULL
;
447 * does this i_mark think it is in the idr? we shouldn't get called
451 WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p"
452 " i_mark->inode=%p\n", __func__
, i_mark
, i_mark
->wd
,
453 i_mark
->fsn_mark
.group
, i_mark
->fsn_mark
.i
.inode
);
457 /* Lets look in the idr to see if we find it */
458 found_i_mark
= inotify_idr_find_locked(group
, wd
);
459 if (unlikely(!found_i_mark
)) {
460 WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p"
461 " i_mark->inode=%p\n", __func__
, i_mark
, i_mark
->wd
,
462 i_mark
->fsn_mark
.group
, i_mark
->fsn_mark
.i
.inode
);
467 * We found an mark in the idr at the right wd, but it's
468 * not the mark we were told to remove. eparis seriously
469 * fucked up somewhere.
471 if (unlikely(found_i_mark
!= i_mark
)) {
472 WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p "
473 "mark->inode=%p found_i_mark=%p found_i_mark->wd=%d "
474 "found_i_mark->group=%p found_i_mark->inode=%p\n",
475 __func__
, i_mark
, i_mark
->wd
, i_mark
->fsn_mark
.group
,
476 i_mark
->fsn_mark
.i
.inode
, found_i_mark
, found_i_mark
->wd
,
477 found_i_mark
->fsn_mark
.group
,
478 found_i_mark
->fsn_mark
.i
.inode
);
483 * One ref for being in the idr
484 * one ref held by the caller trying to kill us
485 * one ref grabbed by inotify_idr_find
487 if (unlikely(atomic_read(&i_mark
->fsn_mark
.refcnt
) < 3)) {
488 printk(KERN_ERR
"%s: i_mark=%p i_mark->wd=%d i_mark->group=%p"
489 " i_mark->inode=%p\n", __func__
, i_mark
, i_mark
->wd
,
490 i_mark
->fsn_mark
.group
, i_mark
->fsn_mark
.i
.inode
);
491 /* we can't really recover with bad ref cnting.. */
495 do_inotify_remove_from_idr(group
, i_mark
);
497 /* match the ref taken by inotify_idr_find_locked() */
499 fsnotify_put_mark(&found_i_mark
->fsn_mark
);
501 spin_unlock(idr_lock
);
505 * Send IN_IGNORED for this wd, remove this wd from the idr.
507 void inotify_ignored_and_remove_idr(struct fsnotify_mark
*fsn_mark
,
508 struct fsnotify_group
*group
)
510 struct inotify_inode_mark
*i_mark
;
511 struct fsnotify_event
*ignored_event
, *notify_event
;
512 struct inotify_event_private_data
*event_priv
;
513 struct fsnotify_event_private_data
*fsn_event_priv
;
516 i_mark
= container_of(fsn_mark
, struct inotify_inode_mark
, fsn_mark
);
518 ignored_event
= fsnotify_create_event(NULL
, FS_IN_IGNORED
, NULL
,
519 FSNOTIFY_EVENT_NONE
, NULL
, 0,
522 goto skip_send_ignore
;
524 event_priv
= kmem_cache_alloc(event_priv_cachep
, GFP_NOFS
);
525 if (unlikely(!event_priv
))
526 goto skip_send_ignore
;
528 fsn_event_priv
= &event_priv
->fsnotify_event_priv_data
;
530 fsnotify_get_group(group
);
531 fsn_event_priv
->group
= group
;
532 event_priv
->wd
= i_mark
->wd
;
534 notify_event
= fsnotify_add_notify_event(group
, ignored_event
, fsn_event_priv
, NULL
);
536 if (IS_ERR(notify_event
))
537 ret
= PTR_ERR(notify_event
);
539 fsnotify_put_event(notify_event
);
540 inotify_free_event_priv(fsn_event_priv
);
544 /* matches the reference taken when the event was created */
546 fsnotify_put_event(ignored_event
);
548 /* remove this mark from the idr */
549 inotify_remove_from_idr(group
, i_mark
);
551 atomic_dec(&group
->inotify_data
.user
->inotify_watches
);
554 /* ding dong the mark is dead */
555 static void inotify_free_mark(struct fsnotify_mark
*fsn_mark
)
557 struct inotify_inode_mark
*i_mark
;
559 i_mark
= container_of(fsn_mark
, struct inotify_inode_mark
, fsn_mark
);
561 kmem_cache_free(inotify_inode_mark_cachep
, i_mark
);
564 static int inotify_update_existing_watch(struct fsnotify_group
*group
,
568 struct fsnotify_mark
*fsn_mark
;
569 struct inotify_inode_mark
*i_mark
;
570 __u32 old_mask
, new_mask
;
572 int add
= (arg
& IN_MASK_ADD
);
575 /* don't allow invalid bits: we don't want flags set */
576 mask
= inotify_arg_to_mask(arg
);
577 if (unlikely(!(mask
& IN_ALL_EVENTS
)))
580 fsn_mark
= fsnotify_find_inode_mark(group
, inode
);
584 i_mark
= container_of(fsn_mark
, struct inotify_inode_mark
, fsn_mark
);
586 spin_lock(&fsn_mark
->lock
);
588 old_mask
= fsn_mark
->mask
;
590 fsnotify_set_mark_mask_locked(fsn_mark
, (fsn_mark
->mask
| mask
));
592 fsnotify_set_mark_mask_locked(fsn_mark
, mask
);
593 new_mask
= fsn_mark
->mask
;
595 spin_unlock(&fsn_mark
->lock
);
597 if (old_mask
!= new_mask
) {
598 /* more bits in old than in new? */
599 int dropped
= (old_mask
& ~new_mask
);
600 /* more bits in this fsn_mark than the inode's mask? */
601 int do_inode
= (new_mask
& ~inode
->i_fsnotify_mask
);
603 /* update the inode with this new fsn_mark */
604 if (dropped
|| do_inode
)
605 fsnotify_recalc_inode_mask(inode
);
612 /* match the get from fsnotify_find_mark() */
613 fsnotify_put_mark(fsn_mark
);
618 static int inotify_new_watch(struct fsnotify_group
*group
,
622 struct inotify_inode_mark
*tmp_i_mark
;
625 struct idr
*idr
= &group
->inotify_data
.idr
;
626 spinlock_t
*idr_lock
= &group
->inotify_data
.idr_lock
;
628 /* don't allow invalid bits: we don't want flags set */
629 mask
= inotify_arg_to_mask(arg
);
630 if (unlikely(!(mask
& IN_ALL_EVENTS
)))
633 tmp_i_mark
= kmem_cache_alloc(inotify_inode_mark_cachep
, GFP_KERNEL
);
634 if (unlikely(!tmp_i_mark
))
637 fsnotify_init_mark(&tmp_i_mark
->fsn_mark
, inotify_free_mark
);
638 tmp_i_mark
->fsn_mark
.mask
= mask
;
642 if (atomic_read(&group
->inotify_data
.user
->inotify_watches
) >= inotify_max_user_watches
)
645 ret
= inotify_add_to_idr(idr
, idr_lock
, &group
->inotify_data
.last_wd
,
650 /* we are on the idr, now get on the inode */
651 ret
= fsnotify_add_mark(&tmp_i_mark
->fsn_mark
, group
, inode
, NULL
, 0);
653 /* we failed to get on the inode, get off the idr */
654 inotify_remove_from_idr(group
, tmp_i_mark
);
658 /* increment the number of watches the user has */
659 atomic_inc(&group
->inotify_data
.user
->inotify_watches
);
661 /* return the watch descriptor for this new mark */
662 ret
= tmp_i_mark
->wd
;
665 /* match the ref from fsnotify_init_mark() */
666 fsnotify_put_mark(&tmp_i_mark
->fsn_mark
);
671 static int inotify_update_watch(struct fsnotify_group
*group
, struct inode
*inode
, u32 arg
)
676 /* try to update and existing watch with the new arg */
677 ret
= inotify_update_existing_watch(group
, inode
, arg
);
678 /* no mark present, try to add a new one */
680 ret
= inotify_new_watch(group
, inode
, arg
);
682 * inotify_new_watch could race with another thread which did an
683 * inotify_new_watch between the update_existing and the add watch
684 * here, go back and try to update an existing mark again.
692 static struct fsnotify_group
*inotify_new_group(unsigned int max_events
)
694 struct fsnotify_group
*group
;
696 group
= fsnotify_alloc_group(&inotify_fsnotify_ops
);
700 group
->max_events
= max_events
;
702 spin_lock_init(&group
->inotify_data
.idr_lock
);
703 idr_init(&group
->inotify_data
.idr
);
704 group
->inotify_data
.last_wd
= 0;
705 group
->inotify_data
.user
= get_current_user();
707 if (atomic_inc_return(&group
->inotify_data
.user
->inotify_devs
) >
708 inotify_max_user_instances
) {
709 fsnotify_destroy_group(group
);
710 return ERR_PTR(-EMFILE
);
717 /* inotify syscalls */
718 SYSCALL_DEFINE1(inotify_init1
, int, flags
)
720 struct fsnotify_group
*group
;
723 /* Check the IN_* constants for consistency. */
724 BUILD_BUG_ON(IN_CLOEXEC
!= O_CLOEXEC
);
725 BUILD_BUG_ON(IN_NONBLOCK
!= O_NONBLOCK
);
727 if (flags
& ~(IN_CLOEXEC
| IN_NONBLOCK
))
730 /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */
731 group
= inotify_new_group(inotify_max_queued_events
);
733 return PTR_ERR(group
);
735 ret
= anon_inode_getfd("inotify", &inotify_fops
, group
,
738 fsnotify_destroy_group(group
);
743 SYSCALL_DEFINE0(inotify_init
)
745 return sys_inotify_init1(0);
748 SYSCALL_DEFINE3(inotify_add_watch
, int, fd
, const char __user
*, pathname
,
751 struct fsnotify_group
*group
;
755 int ret
, fput_needed
;
758 filp
= fget_light(fd
, &fput_needed
);
762 /* verify that this is indeed an inotify instance */
763 if (unlikely(filp
->f_op
!= &inotify_fops
)) {
768 if (!(mask
& IN_DONT_FOLLOW
))
769 flags
|= LOOKUP_FOLLOW
;
770 if (mask
& IN_ONLYDIR
)
771 flags
|= LOOKUP_DIRECTORY
;
773 ret
= inotify_find_inode(pathname
, &path
, flags
);
777 /* inode held in place by reference to path; group by fget on fd */
778 inode
= path
.dentry
->d_inode
;
779 group
= filp
->private_data
;
781 /* create/update an inode mark */
782 ret
= inotify_update_watch(group
, inode
, mask
);
785 fput_light(filp
, fput_needed
);
789 SYSCALL_DEFINE2(inotify_rm_watch
, int, fd
, __s32
, wd
)
791 struct fsnotify_group
*group
;
792 struct inotify_inode_mark
*i_mark
;
794 int ret
= 0, fput_needed
;
796 filp
= fget_light(fd
, &fput_needed
);
800 /* verify that this is indeed an inotify instance */
802 if (unlikely(filp
->f_op
!= &inotify_fops
))
805 group
= filp
->private_data
;
808 i_mark
= inotify_idr_find(group
, wd
);
809 if (unlikely(!i_mark
))
814 fsnotify_destroy_mark(&i_mark
->fsn_mark
, group
);
816 /* match ref taken by inotify_idr_find */
817 fsnotify_put_mark(&i_mark
->fsn_mark
);
820 fput_light(filp
, fput_needed
);
825 * inotify_user_setup - Our initialization function. Note that we cannot return
826 * error because we have compiled-in VFS hooks. So an (unlikely) failure here
827 * must result in panic().
829 static int __init
inotify_user_setup(void)
831 BUILD_BUG_ON(IN_ACCESS
!= FS_ACCESS
);
832 BUILD_BUG_ON(IN_MODIFY
!= FS_MODIFY
);
833 BUILD_BUG_ON(IN_ATTRIB
!= FS_ATTRIB
);
834 BUILD_BUG_ON(IN_CLOSE_WRITE
!= FS_CLOSE_WRITE
);
835 BUILD_BUG_ON(IN_CLOSE_NOWRITE
!= FS_CLOSE_NOWRITE
);
836 BUILD_BUG_ON(IN_OPEN
!= FS_OPEN
);
837 BUILD_BUG_ON(IN_MOVED_FROM
!= FS_MOVED_FROM
);
838 BUILD_BUG_ON(IN_MOVED_TO
!= FS_MOVED_TO
);
839 BUILD_BUG_ON(IN_CREATE
!= FS_CREATE
);
840 BUILD_BUG_ON(IN_DELETE
!= FS_DELETE
);
841 BUILD_BUG_ON(IN_DELETE_SELF
!= FS_DELETE_SELF
);
842 BUILD_BUG_ON(IN_MOVE_SELF
!= FS_MOVE_SELF
);
843 BUILD_BUG_ON(IN_UNMOUNT
!= FS_UNMOUNT
);
844 BUILD_BUG_ON(IN_Q_OVERFLOW
!= FS_Q_OVERFLOW
);
845 BUILD_BUG_ON(IN_IGNORED
!= FS_IN_IGNORED
);
846 BUILD_BUG_ON(IN_EXCL_UNLINK
!= FS_EXCL_UNLINK
);
847 BUILD_BUG_ON(IN_ISDIR
!= FS_ISDIR
);
848 BUILD_BUG_ON(IN_ONESHOT
!= FS_IN_ONESHOT
);
850 BUG_ON(hweight32(ALL_INOTIFY_BITS
) != 21);
852 inotify_inode_mark_cachep
= KMEM_CACHE(inotify_inode_mark
, SLAB_PANIC
);
853 event_priv_cachep
= KMEM_CACHE(inotify_event_private_data
, SLAB_PANIC
);
855 inotify_max_queued_events
= 16384;
856 inotify_max_user_instances
= 128;
857 inotify_max_user_watches
= 8192;
861 module_init(inotify_user_setup
);