blob: abc8cbcfe90e0fca9f67471740c0b41c9055b7c6 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Directory notifications for Linux.
3 *
4 * Copyright (C) 2000,2001,2002 Stephen Rothwell
5 *
Eric Paris3c5119c2009-05-21 17:01:33 -04006 * Copyright (C) 2009 Eric Paris <Red Hat Inc>
7 * dnotify was largly rewritten to use the new fsnotify infrastructure
8 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2, or (at your option) any
12 * later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 */
19#include <linux/fs.h>
20#include <linux/module.h>
21#include <linux/sched.h>
22#include <linux/dnotify.h>
23#include <linux/init.h>
24#include <linux/spinlock.h>
25#include <linux/slab.h>
Al Viro9f3acc32008-04-24 07:44:08 -040026#include <linux/fdtable.h>
Eric Paris3c5119c2009-05-21 17:01:33 -040027#include <linux/fsnotify_backend.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
Eric Dumazetfa3536c2006-03-26 01:37:24 -080029int dir_notify_enable __read_mostly = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070030
Eric Paris3c5119c2009-05-21 17:01:33 -040031static struct kmem_cache *dnotify_struct_cache __read_mostly;
Eric Parisef5e2b72009-12-17 21:24:24 -050032static struct kmem_cache *dnotify_mark_cache __read_mostly;
Eric Paris3c5119c2009-05-21 17:01:33 -040033static struct fsnotify_group *dnotify_group __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
Eric Paris3c5119c2009-05-21 17:01:33 -040035/*
Eric Parise61ce862009-12-17 21:24:24 -050036 * dnotify will attach one of these to each inode (i_fsnotify_marks) which
Eric Paris3c5119c2009-05-21 17:01:33 -040037 * is being watched by dnotify. If multiple userspace applications are watching
38 * the same directory with dnotify their information is chained in dn
39 */
Eric Parisef5e2b72009-12-17 21:24:24 -050040struct dnotify_mark {
41 struct fsnotify_mark fsn_mark;
Linus Torvalds1da177e2005-04-16 15:20:36 -070042 struct dnotify_struct *dn;
Eric Paris3c5119c2009-05-21 17:01:33 -040043};
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Eric Paris3c5119c2009-05-21 17:01:33 -040045/*
46 * When a process starts or stops watching an inode the set of events which
47 * dnotify cares about for that inode may change. This function runs the
48 * list of everything receiving dnotify events about this directory and calculates
49 * the set of all those events. After it updates what dnotify is interested in
50 * it calls the fsnotify function so it can update the set of all events relevant
51 * to this inode.
52 */
Eric Parisef5e2b72009-12-17 21:24:24 -050053static void dnotify_recalc_inode_mask(struct fsnotify_mark *fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -040054{
55 __u32 new_mask, old_mask;
56 struct dnotify_struct *dn;
Eric Parisef5e2b72009-12-17 21:24:24 -050057 struct dnotify_mark *dn_mark = container_of(fsn_mark,
58 struct dnotify_mark,
59 fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -040060
Eric Parisef5e2b72009-12-17 21:24:24 -050061 assert_spin_locked(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -040062
Eric Parisef5e2b72009-12-17 21:24:24 -050063 old_mask = fsn_mark->mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 new_mask = 0;
Eric Parisef5e2b72009-12-17 21:24:24 -050065 for (dn = dn_mark->dn; dn != NULL; dn = dn->dn_next)
Eric Paris3c5119c2009-05-21 17:01:33 -040066 new_mask |= (dn->dn_mask & ~FS_DN_MULTISHOT);
Eric Paris90b1e7a2009-12-17 21:24:33 -050067 fsnotify_set_mark_mask_locked(fsn_mark, new_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
Eric Paris3c5119c2009-05-21 17:01:33 -040069 if (old_mask == new_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 return;
Eric Paris3c5119c2009-05-21 17:01:33 -040071
Eric Parisef5e2b72009-12-17 21:24:24 -050072 if (fsn_mark->i.inode)
73 fsnotify_recalc_inode_mask(fsn_mark->i.inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -070074}
75
Eric Paris3c5119c2009-05-21 17:01:33 -040076/*
77 * Mains fsnotify call where events are delivered to dnotify.
78 * Find the dnotify mark on the relevant inode, run the list of dnotify structs
79 * on that mark and determine which of them has expressed interest in receiving
80 * events of this type. When found send the correct process and signal and
81 * destroy the dnotify struct if it was not registered to receive multiple
82 * events.
83 */
84static int dnotify_handle_event(struct fsnotify_group *group,
Jan Kara7053aee2014-01-21 15:48:14 -080085 struct inode *inode,
Eric Parisce8f76f2010-07-28 10:18:39 -040086 struct fsnotify_mark *inode_mark,
87 struct fsnotify_mark *vfsmount_mark,
Jan Kara7053aee2014-01-21 15:48:14 -080088 u32 mask, void *data, int data_type,
Jan Kara45a22f42014-02-17 13:09:50 +010089 const unsigned char *file_name, u32 cookie)
Linus Torvalds1da177e2005-04-16 15:20:36 -070090{
Eric Parisef5e2b72009-12-17 21:24:24 -050091 struct dnotify_mark *dn_mark;
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 struct dnotify_struct *dn;
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 struct dnotify_struct **prev;
Eric Paris3c5119c2009-05-21 17:01:33 -040094 struct fown_struct *fown;
Jan Kara7053aee2014-01-21 15:48:14 -080095 __u32 test_mask = mask & ~FS_EVENT_ON_CHILD;
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Jan Kara83c4c4b2014-01-21 15:48:15 -080097 /* not a dir, dnotify doesn't care */
98 if (!S_ISDIR(inode->i_mode))
99 return 0;
100
Eric Parisce8f76f2010-07-28 10:18:39 -0400101 BUG_ON(vfsmount_mark);
102
Eric Parisce8f76f2010-07-28 10:18:39 -0400103 dn_mark = container_of(inode_mark, struct dnotify_mark, fsn_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104
Eric Parisce8f76f2010-07-28 10:18:39 -0400105 spin_lock(&inode_mark->lock);
Eric Parisef5e2b72009-12-17 21:24:24 -0500106 prev = &dn_mark->dn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 while ((dn = *prev) != NULL) {
Andreas Gruenbacher94552682009-10-15 00:13:23 +0200108 if ((dn->dn_mask & test_mask) == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 prev = &dn->dn_next;
110 continue;
111 }
112 fown = &dn->dn_filp->f_owner;
113 send_sigio(fown, dn->dn_fd, POLL_MSG);
Eric Paris3c5119c2009-05-21 17:01:33 -0400114 if (dn->dn_mask & FS_DN_MULTISHOT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 prev = &dn->dn_next;
116 else {
117 *prev = dn->dn_next;
Eric Paris3c5119c2009-05-21 17:01:33 -0400118 kmem_cache_free(dnotify_struct_cache, dn);
Eric Parisce8f76f2010-07-28 10:18:39 -0400119 dnotify_recalc_inode_mask(inode_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 }
121 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122
Eric Parisce8f76f2010-07-28 10:18:39 -0400123 spin_unlock(&inode_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400124
125 return 0;
126}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127
Eric Parisef5e2b72009-12-17 21:24:24 -0500128static void dnotify_free_mark(struct fsnotify_mark *fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400129{
Eric Parisef5e2b72009-12-17 21:24:24 -0500130 struct dnotify_mark *dn_mark = container_of(fsn_mark,
131 struct dnotify_mark,
132 fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400133
Eric Parisef5e2b72009-12-17 21:24:24 -0500134 BUG_ON(dn_mark->dn);
Eric Paris3c5119c2009-05-21 17:01:33 -0400135
Eric Parisef5e2b72009-12-17 21:24:24 -0500136 kmem_cache_free(dnotify_mark_cache, dn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400137}
138
139static struct fsnotify_ops dnotify_fsnotify_ops = {
140 .handle_event = dnotify_handle_event,
Eric Paris3c5119c2009-05-21 17:01:33 -0400141};
142
143/*
144 * Called every time a file is closed. Looks first for a dnotify mark on the
Eric Parise61ce862009-12-17 21:24:24 -0500145 * inode. If one is found run all of the ->dn structures attached to that
Eric Paris3c5119c2009-05-21 17:01:33 -0400146 * mark for one relevant to this process closing the file and remove that
147 * dnotify_struct. If that was the last dnotify_struct also remove the
Eric Parise61ce862009-12-17 21:24:24 -0500148 * fsnotify_mark.
Eric Paris3c5119c2009-05-21 17:01:33 -0400149 */
150void dnotify_flush(struct file *filp, fl_owner_t id)
151{
Eric Parisef5e2b72009-12-17 21:24:24 -0500152 struct fsnotify_mark *fsn_mark;
153 struct dnotify_mark *dn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -0400154 struct dnotify_struct *dn;
155 struct dnotify_struct **prev;
156 struct inode *inode;
157
Al Viro496ad9a2013-01-23 17:07:38 -0500158 inode = file_inode(filp);
Eric Paris3c5119c2009-05-21 17:01:33 -0400159 if (!S_ISDIR(inode->i_mode))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 return;
161
Eric Paris5444e292009-12-17 21:24:27 -0500162 fsn_mark = fsnotify_find_inode_mark(dnotify_group, inode);
Eric Parisef5e2b72009-12-17 21:24:24 -0500163 if (!fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400164 return;
Eric Parisef5e2b72009-12-17 21:24:24 -0500165 dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400166
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700167 mutex_lock(&dnotify_group->mark_mutex);
Eric Paris3c5119c2009-05-21 17:01:33 -0400168
Eric Parisef5e2b72009-12-17 21:24:24 -0500169 spin_lock(&fsn_mark->lock);
170 prev = &dn_mark->dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400171 while ((dn = *prev) != NULL) {
172 if ((dn->dn_owner == id) && (dn->dn_filp == filp)) {
173 *prev = dn->dn_next;
174 kmem_cache_free(dnotify_struct_cache, dn);
Eric Parisef5e2b72009-12-17 21:24:24 -0500175 dnotify_recalc_inode_mask(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400176 break;
177 }
178 prev = &dn->dn_next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 }
Eric Paris3c5119c2009-05-21 17:01:33 -0400180
Eric Parisef5e2b72009-12-17 21:24:24 -0500181 spin_unlock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400182
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700183 /* nothing else could have found us thanks to the dnotify_groups
184 mark_mutex */
Eric Parisef5e2b72009-12-17 21:24:24 -0500185 if (dn_mark->dn == NULL)
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700186 fsnotify_destroy_mark_locked(fsn_mark, dnotify_group);
Eric Paris3c5119c2009-05-21 17:01:33 -0400187
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700188 mutex_unlock(&dnotify_group->mark_mutex);
Eric Paris3c5119c2009-05-21 17:01:33 -0400189
Eric Parisef5e2b72009-12-17 21:24:24 -0500190 fsnotify_put_mark(fsn_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191}
Eric Paris3c5119c2009-05-21 17:01:33 -0400192
193/* this conversion is done only at watch creation */
194static __u32 convert_arg(unsigned long arg)
195{
196 __u32 new_mask = FS_EVENT_ON_CHILD;
197
198 if (arg & DN_MULTISHOT)
199 new_mask |= FS_DN_MULTISHOT;
200 if (arg & DN_DELETE)
201 new_mask |= (FS_DELETE | FS_MOVED_FROM);
202 if (arg & DN_MODIFY)
203 new_mask |= FS_MODIFY;
204 if (arg & DN_ACCESS)
205 new_mask |= FS_ACCESS;
206 if (arg & DN_ATTRIB)
207 new_mask |= FS_ATTRIB;
208 if (arg & DN_RENAME)
209 new_mask |= FS_DN_RENAME;
210 if (arg & DN_CREATE)
211 new_mask |= (FS_CREATE | FS_MOVED_TO);
212
213 return new_mask;
214}
215
216/*
217 * If multiple processes watch the same inode with dnotify there is only one
Eric Parise61ce862009-12-17 21:24:24 -0500218 * dnotify mark in inode->i_fsnotify_marks but we chain a dnotify_struct
Eric Paris3c5119c2009-05-21 17:01:33 -0400219 * onto that mark. This function either attaches the new dnotify_struct onto
220 * that list, or it |= the mask onto an existing dnofiy_struct.
221 */
Eric Parisef5e2b72009-12-17 21:24:24 -0500222static int attach_dn(struct dnotify_struct *dn, struct dnotify_mark *dn_mark,
Eric Paris3c5119c2009-05-21 17:01:33 -0400223 fl_owner_t id, int fd, struct file *filp, __u32 mask)
224{
225 struct dnotify_struct *odn;
226
Eric Parisef5e2b72009-12-17 21:24:24 -0500227 odn = dn_mark->dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400228 while (odn != NULL) {
229 /* adding more events to existing dnofiy_struct? */
230 if ((odn->dn_owner == id) && (odn->dn_filp == filp)) {
231 odn->dn_fd = fd;
232 odn->dn_mask |= mask;
233 return -EEXIST;
234 }
235 odn = odn->dn_next;
236 }
237
238 dn->dn_mask = mask;
239 dn->dn_fd = fd;
240 dn->dn_filp = filp;
241 dn->dn_owner = id;
Eric Parisef5e2b72009-12-17 21:24:24 -0500242 dn->dn_next = dn_mark->dn;
243 dn_mark->dn = dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400244
245 return 0;
246}
247
248/*
249 * When a process calls fcntl to attach a dnotify watch to a directory it ends
250 * up here. Allocate both a mark for fsnotify to add and a dnotify_struct to be
251 * attached to the fsnotify_mark.
252 */
253int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
254{
Eric Parisef5e2b72009-12-17 21:24:24 -0500255 struct dnotify_mark *new_dn_mark, *dn_mark;
256 struct fsnotify_mark *new_fsn_mark, *fsn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -0400257 struct dnotify_struct *dn;
258 struct inode *inode;
259 fl_owner_t id = current->files;
260 struct file *f;
261 int destroy = 0, error = 0;
262 __u32 mask;
263
264 /* we use these to tell if we need to kfree */
Eric Parisef5e2b72009-12-17 21:24:24 -0500265 new_fsn_mark = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400266 dn = NULL;
267
268 if (!dir_notify_enable) {
269 error = -EINVAL;
270 goto out_err;
271 }
272
273 /* a 0 mask means we are explicitly removing the watch */
274 if ((arg & ~DN_MULTISHOT) == 0) {
275 dnotify_flush(filp, id);
276 error = 0;
277 goto out_err;
278 }
279
280 /* dnotify only works on directories */
Al Viro496ad9a2013-01-23 17:07:38 -0500281 inode = file_inode(filp);
Eric Paris3c5119c2009-05-21 17:01:33 -0400282 if (!S_ISDIR(inode->i_mode)) {
283 error = -ENOTDIR;
284 goto out_err;
285 }
286
287 /* expect most fcntl to add new rather than augment old */
288 dn = kmem_cache_alloc(dnotify_struct_cache, GFP_KERNEL);
289 if (!dn) {
290 error = -ENOMEM;
291 goto out_err;
292 }
293
294 /* new fsnotify mark, we expect most fcntl calls to add a new mark */
Eric Parisef5e2b72009-12-17 21:24:24 -0500295 new_dn_mark = kmem_cache_alloc(dnotify_mark_cache, GFP_KERNEL);
296 if (!new_dn_mark) {
Eric Paris3c5119c2009-05-21 17:01:33 -0400297 error = -ENOMEM;
298 goto out_err;
299 }
300
301 /* convert the userspace DN_* "arg" to the internal FS_* defines in fsnotify */
302 mask = convert_arg(arg);
303
Eric Parisef5e2b72009-12-17 21:24:24 -0500304 /* set up the new_fsn_mark and new_dn_mark */
305 new_fsn_mark = &new_dn_mark->fsn_mark;
306 fsnotify_init_mark(new_fsn_mark, dnotify_free_mark);
307 new_fsn_mark->mask = mask;
308 new_dn_mark->dn = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400309
310 /* this is needed to prevent the fcntl/close race described below */
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700311 mutex_lock(&dnotify_group->mark_mutex);
Eric Paris3c5119c2009-05-21 17:01:33 -0400312
Eric Parisef5e2b72009-12-17 21:24:24 -0500313 /* add the new_fsn_mark or find an old one. */
Eric Paris5444e292009-12-17 21:24:27 -0500314 fsn_mark = fsnotify_find_inode_mark(dnotify_group, inode);
Eric Parisef5e2b72009-12-17 21:24:24 -0500315 if (fsn_mark) {
316 dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
317 spin_lock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400318 } else {
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700319 fsnotify_add_mark_locked(new_fsn_mark, dnotify_group, inode,
320 NULL, 0);
Eric Parisef5e2b72009-12-17 21:24:24 -0500321 spin_lock(&new_fsn_mark->lock);
322 fsn_mark = new_fsn_mark;
323 dn_mark = new_dn_mark;
324 /* we used new_fsn_mark, so don't free it */
325 new_fsn_mark = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400326 }
327
328 rcu_read_lock();
329 f = fcheck(fd);
330 rcu_read_unlock();
331
332 /* if (f != filp) means that we lost a race and another task/thread
333 * actually closed the fd we are still playing with before we grabbed
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700334 * the dnotify_groups mark_mutex and fsn_mark->lock. Since closing the
335 * fd is the only time we clean up the marks we need to get our mark
336 * off the list. */
Eric Paris3c5119c2009-05-21 17:01:33 -0400337 if (f != filp) {
338 /* if we added ourselves, shoot ourselves, it's possible that
Eric Parisef5e2b72009-12-17 21:24:24 -0500339 * the flush actually did shoot this fsn_mark. That's fine too
Eric Paris3c5119c2009-05-21 17:01:33 -0400340 * since multiple calls to destroy_mark is perfectly safe, if
Eric Parisef5e2b72009-12-17 21:24:24 -0500341 * we found a dn_mark already attached to the inode, just sod
Eric Paris3c5119c2009-05-21 17:01:33 -0400342 * off silently as the flush at close time dealt with it.
343 */
Eric Parisef5e2b72009-12-17 21:24:24 -0500344 if (dn_mark == new_dn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400345 destroy = 1;
346 goto out;
347 }
348
349 error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
350 if (error) {
351 /* if we added, we must shoot */
Eric Parisef5e2b72009-12-17 21:24:24 -0500352 if (dn_mark == new_dn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400353 destroy = 1;
354 goto out;
355 }
356
Eric Parisef5e2b72009-12-17 21:24:24 -0500357 error = attach_dn(dn, dn_mark, id, fd, filp, mask);
358 /* !error means that we attached the dn to the dn_mark, so don't free it */
Eric Paris3c5119c2009-05-21 17:01:33 -0400359 if (!error)
360 dn = NULL;
361 /* -EEXIST means that we didn't add this new dn and used an old one.
362 * that isn't an error (and the unused dn should be freed) */
363 else if (error == -EEXIST)
364 error = 0;
365
Eric Parisef5e2b72009-12-17 21:24:24 -0500366 dnotify_recalc_inode_mask(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400367out:
Eric Parisef5e2b72009-12-17 21:24:24 -0500368 spin_unlock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400369
370 if (destroy)
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700371 fsnotify_destroy_mark_locked(fsn_mark, dnotify_group);
Eric Paris3c5119c2009-05-21 17:01:33 -0400372
Lino Sanfilippo52f85722013-07-08 15:59:44 -0700373 mutex_unlock(&dnotify_group->mark_mutex);
Eric Parisef5e2b72009-12-17 21:24:24 -0500374 fsnotify_put_mark(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400375out_err:
Eric Parisef5e2b72009-12-17 21:24:24 -0500376 if (new_fsn_mark)
377 fsnotify_put_mark(new_fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400378 if (dn)
379 kmem_cache_free(dnotify_struct_cache, dn);
380 return error;
381}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
383static int __init dnotify_init(void)
384{
Eric Paris3c5119c2009-05-21 17:01:33 -0400385 dnotify_struct_cache = KMEM_CACHE(dnotify_struct, SLAB_PANIC);
Eric Parisef5e2b72009-12-17 21:24:24 -0500386 dnotify_mark_cache = KMEM_CACHE(dnotify_mark, SLAB_PANIC);
Eric Paris3c5119c2009-05-21 17:01:33 -0400387
Eric Paris0d2e2a12009-12-17 21:24:22 -0500388 dnotify_group = fsnotify_alloc_group(&dnotify_fsnotify_ops);
Eric Paris3c5119c2009-05-21 17:01:33 -0400389 if (IS_ERR(dnotify_group))
390 panic("unable to allocate fsnotify group for dnotify\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 return 0;
392}
393
394module_init(dnotify_init)