blob: 2bfe6dc413a0e7cf6adebda205d957e1d2fe4ebe [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;
34static DEFINE_MUTEX(dnotify_mark_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
Eric Paris3c5119c2009-05-21 17:01:33 -040036/*
Eric Parise61ce862009-12-17 21:24:24 -050037 * dnotify will attach one of these to each inode (i_fsnotify_marks) which
Eric Paris3c5119c2009-05-21 17:01:33 -040038 * is being watched by dnotify. If multiple userspace applications are watching
39 * the same directory with dnotify their information is chained in dn
40 */
Eric Parisef5e2b72009-12-17 21:24:24 -050041struct dnotify_mark {
42 struct fsnotify_mark fsn_mark;
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 struct dnotify_struct *dn;
Eric Paris3c5119c2009-05-21 17:01:33 -040044};
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
Eric Paris3c5119c2009-05-21 17:01:33 -040046/*
47 * When a process starts or stops watching an inode the set of events which
48 * dnotify cares about for that inode may change. This function runs the
49 * list of everything receiving dnotify events about this directory and calculates
50 * the set of all those events. After it updates what dnotify is interested in
51 * it calls the fsnotify function so it can update the set of all events relevant
52 * to this inode.
53 */
Eric Parisef5e2b72009-12-17 21:24:24 -050054static void dnotify_recalc_inode_mask(struct fsnotify_mark *fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -040055{
56 __u32 new_mask, old_mask;
57 struct dnotify_struct *dn;
Eric Parisef5e2b72009-12-17 21:24:24 -050058 struct dnotify_mark *dn_mark = container_of(fsn_mark,
59 struct dnotify_mark,
60 fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -040061
Eric Parisef5e2b72009-12-17 21:24:24 -050062 assert_spin_locked(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -040063
Eric Parisef5e2b72009-12-17 21:24:24 -050064 old_mask = fsn_mark->mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 new_mask = 0;
Eric Parisef5e2b72009-12-17 21:24:24 -050066 for (dn = dn_mark->dn; dn != NULL; dn = dn->dn_next)
Eric Paris3c5119c2009-05-21 17:01:33 -040067 new_mask |= (dn->dn_mask & ~FS_DN_MULTISHOT);
Eric Paris90b1e7a2009-12-17 21:24:33 -050068 fsnotify_set_mark_mask_locked(fsn_mark, new_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -070069
Eric Paris3c5119c2009-05-21 17:01:33 -040070 if (old_mask == new_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 return;
Eric Paris3c5119c2009-05-21 17:01:33 -040072
Eric Parisef5e2b72009-12-17 21:24:24 -050073 if (fsn_mark->i.inode)
74 fsnotify_recalc_inode_mask(fsn_mark->i.inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -070075}
76
Eric Paris3c5119c2009-05-21 17:01:33 -040077/*
78 * Mains fsnotify call where events are delivered to dnotify.
79 * Find the dnotify mark on the relevant inode, run the list of dnotify structs
80 * on that mark and determine which of them has expressed interest in receiving
81 * events of this type. When found send the correct process and signal and
82 * destroy the dnotify struct if it was not registered to receive multiple
83 * events.
84 */
85static int dnotify_handle_event(struct fsnotify_group *group,
Eric Parisce8f76f2010-07-28 10:18:39 -040086 struct fsnotify_mark *inode_mark,
87 struct fsnotify_mark *vfsmount_mark,
Eric Paris3c5119c2009-05-21 17:01:33 -040088 struct fsnotify_event *event)
Linus Torvalds1da177e2005-04-16 15:20:36 -070089{
Eric Parisef5e2b72009-12-17 21:24:24 -050090 struct dnotify_mark *dn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -040091 struct inode *to_tell;
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;
Andreas Gruenbacher94552682009-10-15 00:13:23 +020095 __u32 test_mask = event->mask & ~FS_EVENT_ON_CHILD;
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Eric Parisce8f76f2010-07-28 10:18:39 -040097 BUG_ON(vfsmount_mark);
98
Eric Paris3c5119c2009-05-21 17:01:33 -040099 to_tell = event->to_tell;
100
Eric Parisce8f76f2010-07-28 10:18:39 -0400101 dn_mark = container_of(inode_mark, struct dnotify_mark, fsn_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
Eric Parisce8f76f2010-07-28 10:18:39 -0400103 spin_lock(&inode_mark->lock);
Eric Parisef5e2b72009-12-17 21:24:24 -0500104 prev = &dn_mark->dn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 while ((dn = *prev) != NULL) {
Andreas Gruenbacher94552682009-10-15 00:13:23 +0200106 if ((dn->dn_mask & test_mask) == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 prev = &dn->dn_next;
108 continue;
109 }
110 fown = &dn->dn_filp->f_owner;
111 send_sigio(fown, dn->dn_fd, POLL_MSG);
Eric Paris3c5119c2009-05-21 17:01:33 -0400112 if (dn->dn_mask & FS_DN_MULTISHOT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 prev = &dn->dn_next;
114 else {
115 *prev = dn->dn_next;
Eric Paris3c5119c2009-05-21 17:01:33 -0400116 kmem_cache_free(dnotify_struct_cache, dn);
Eric Parisce8f76f2010-07-28 10:18:39 -0400117 dnotify_recalc_inode_mask(inode_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 }
119 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
Eric Parisce8f76f2010-07-28 10:18:39 -0400121 spin_unlock(&inode_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400122
123 return 0;
124}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
126/*
Eric Paris3c5119c2009-05-21 17:01:33 -0400127 * Given an inode and mask determine if dnotify would be interested in sending
128 * userspace notification for that pair.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 */
Eric Paris3c5119c2009-05-21 17:01:33 -0400130static bool dnotify_should_send_event(struct fsnotify_group *group,
Eric Paris1968f5e2010-07-28 10:18:39 -0400131 struct inode *inode,
Eric Parisce8f76f2010-07-28 10:18:39 -0400132 struct fsnotify_mark *inode_mark,
133 struct fsnotify_mark *vfsmount_mark,
134 __u32 mask, void *data, int data_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135{
Eric Paris3c5119c2009-05-21 17:01:33 -0400136 /* not a dir, dnotify doesn't care */
137 if (!S_ISDIR(inode->i_mode))
138 return false;
139
Eric Paris2612abb2010-07-28 10:18:39 -0400140 return true;
Eric Paris3c5119c2009-05-21 17:01:33 -0400141}
142
Eric Parisef5e2b72009-12-17 21:24:24 -0500143static void dnotify_free_mark(struct fsnotify_mark *fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400144{
Eric Parisef5e2b72009-12-17 21:24:24 -0500145 struct dnotify_mark *dn_mark = container_of(fsn_mark,
146 struct dnotify_mark,
147 fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400148
Eric Parisef5e2b72009-12-17 21:24:24 -0500149 BUG_ON(dn_mark->dn);
Eric Paris3c5119c2009-05-21 17:01:33 -0400150
Eric Parisef5e2b72009-12-17 21:24:24 -0500151 kmem_cache_free(dnotify_mark_cache, dn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400152}
153
154static struct fsnotify_ops dnotify_fsnotify_ops = {
155 .handle_event = dnotify_handle_event,
156 .should_send_event = dnotify_should_send_event,
157 .free_group_priv = NULL,
Eric Parisa092ee22009-06-11 11:09:48 -0400158 .freeing_mark = NULL,
Eric Parise4aff112009-05-21 17:01:50 -0400159 .free_event_priv = NULL,
Eric Paris3c5119c2009-05-21 17:01:33 -0400160};
161
162/*
163 * Called every time a file is closed. Looks first for a dnotify mark on the
Eric Parise61ce862009-12-17 21:24:24 -0500164 * inode. If one is found run all of the ->dn structures attached to that
Eric Paris3c5119c2009-05-21 17:01:33 -0400165 * mark for one relevant to this process closing the file and remove that
166 * dnotify_struct. If that was the last dnotify_struct also remove the
Eric Parise61ce862009-12-17 21:24:24 -0500167 * fsnotify_mark.
Eric Paris3c5119c2009-05-21 17:01:33 -0400168 */
169void dnotify_flush(struct file *filp, fl_owner_t id)
170{
Eric Parisef5e2b72009-12-17 21:24:24 -0500171 struct fsnotify_mark *fsn_mark;
172 struct dnotify_mark *dn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -0400173 struct dnotify_struct *dn;
174 struct dnotify_struct **prev;
175 struct inode *inode;
176
Al Viro496ad9a2013-01-23 17:07:38 -0500177 inode = file_inode(filp);
Eric Paris3c5119c2009-05-21 17:01:33 -0400178 if (!S_ISDIR(inode->i_mode))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 return;
180
Eric Paris5444e292009-12-17 21:24:27 -0500181 fsn_mark = fsnotify_find_inode_mark(dnotify_group, inode);
Eric Parisef5e2b72009-12-17 21:24:24 -0500182 if (!fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400183 return;
Eric Parisef5e2b72009-12-17 21:24:24 -0500184 dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400185
186 mutex_lock(&dnotify_mark_mutex);
187
Eric Parisef5e2b72009-12-17 21:24:24 -0500188 spin_lock(&fsn_mark->lock);
189 prev = &dn_mark->dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400190 while ((dn = *prev) != NULL) {
191 if ((dn->dn_owner == id) && (dn->dn_filp == filp)) {
192 *prev = dn->dn_next;
193 kmem_cache_free(dnotify_struct_cache, dn);
Eric Parisef5e2b72009-12-17 21:24:24 -0500194 dnotify_recalc_inode_mask(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400195 break;
196 }
197 prev = &dn->dn_next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 }
Eric Paris3c5119c2009-05-21 17:01:33 -0400199
Eric Parisef5e2b72009-12-17 21:24:24 -0500200 spin_unlock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400201
202 /* nothing else could have found us thanks to the dnotify_mark_mutex */
Eric Parisef5e2b72009-12-17 21:24:24 -0500203 if (dn_mark->dn == NULL)
Lino Sanfilippoe2a29942011-06-14 17:29:51 +0200204 fsnotify_destroy_mark(fsn_mark, dnotify_group);
Eric Paris3c5119c2009-05-21 17:01:33 -0400205
Eric Paris3c5119c2009-05-21 17:01:33 -0400206 mutex_unlock(&dnotify_mark_mutex);
207
Eric Parisef5e2b72009-12-17 21:24:24 -0500208 fsnotify_put_mark(fsn_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209}
Eric Paris3c5119c2009-05-21 17:01:33 -0400210
211/* this conversion is done only at watch creation */
212static __u32 convert_arg(unsigned long arg)
213{
214 __u32 new_mask = FS_EVENT_ON_CHILD;
215
216 if (arg & DN_MULTISHOT)
217 new_mask |= FS_DN_MULTISHOT;
218 if (arg & DN_DELETE)
219 new_mask |= (FS_DELETE | FS_MOVED_FROM);
220 if (arg & DN_MODIFY)
221 new_mask |= FS_MODIFY;
222 if (arg & DN_ACCESS)
223 new_mask |= FS_ACCESS;
224 if (arg & DN_ATTRIB)
225 new_mask |= FS_ATTRIB;
226 if (arg & DN_RENAME)
227 new_mask |= FS_DN_RENAME;
228 if (arg & DN_CREATE)
229 new_mask |= (FS_CREATE | FS_MOVED_TO);
230
231 return new_mask;
232}
233
234/*
235 * If multiple processes watch the same inode with dnotify there is only one
Eric Parise61ce862009-12-17 21:24:24 -0500236 * dnotify mark in inode->i_fsnotify_marks but we chain a dnotify_struct
Eric Paris3c5119c2009-05-21 17:01:33 -0400237 * onto that mark. This function either attaches the new dnotify_struct onto
238 * that list, or it |= the mask onto an existing dnofiy_struct.
239 */
Eric Parisef5e2b72009-12-17 21:24:24 -0500240static int attach_dn(struct dnotify_struct *dn, struct dnotify_mark *dn_mark,
Eric Paris3c5119c2009-05-21 17:01:33 -0400241 fl_owner_t id, int fd, struct file *filp, __u32 mask)
242{
243 struct dnotify_struct *odn;
244
Eric Parisef5e2b72009-12-17 21:24:24 -0500245 odn = dn_mark->dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400246 while (odn != NULL) {
247 /* adding more events to existing dnofiy_struct? */
248 if ((odn->dn_owner == id) && (odn->dn_filp == filp)) {
249 odn->dn_fd = fd;
250 odn->dn_mask |= mask;
251 return -EEXIST;
252 }
253 odn = odn->dn_next;
254 }
255
256 dn->dn_mask = mask;
257 dn->dn_fd = fd;
258 dn->dn_filp = filp;
259 dn->dn_owner = id;
Eric Parisef5e2b72009-12-17 21:24:24 -0500260 dn->dn_next = dn_mark->dn;
261 dn_mark->dn = dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400262
263 return 0;
264}
265
266/*
267 * When a process calls fcntl to attach a dnotify watch to a directory it ends
268 * up here. Allocate both a mark for fsnotify to add and a dnotify_struct to be
269 * attached to the fsnotify_mark.
270 */
271int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
272{
Eric Parisef5e2b72009-12-17 21:24:24 -0500273 struct dnotify_mark *new_dn_mark, *dn_mark;
274 struct fsnotify_mark *new_fsn_mark, *fsn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -0400275 struct dnotify_struct *dn;
276 struct inode *inode;
277 fl_owner_t id = current->files;
278 struct file *f;
279 int destroy = 0, error = 0;
280 __u32 mask;
281
282 /* we use these to tell if we need to kfree */
Eric Parisef5e2b72009-12-17 21:24:24 -0500283 new_fsn_mark = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400284 dn = NULL;
285
286 if (!dir_notify_enable) {
287 error = -EINVAL;
288 goto out_err;
289 }
290
291 /* a 0 mask means we are explicitly removing the watch */
292 if ((arg & ~DN_MULTISHOT) == 0) {
293 dnotify_flush(filp, id);
294 error = 0;
295 goto out_err;
296 }
297
298 /* dnotify only works on directories */
Al Viro496ad9a2013-01-23 17:07:38 -0500299 inode = file_inode(filp);
Eric Paris3c5119c2009-05-21 17:01:33 -0400300 if (!S_ISDIR(inode->i_mode)) {
301 error = -ENOTDIR;
302 goto out_err;
303 }
304
305 /* expect most fcntl to add new rather than augment old */
306 dn = kmem_cache_alloc(dnotify_struct_cache, GFP_KERNEL);
307 if (!dn) {
308 error = -ENOMEM;
309 goto out_err;
310 }
311
312 /* new fsnotify mark, we expect most fcntl calls to add a new mark */
Eric Parisef5e2b72009-12-17 21:24:24 -0500313 new_dn_mark = kmem_cache_alloc(dnotify_mark_cache, GFP_KERNEL);
314 if (!new_dn_mark) {
Eric Paris3c5119c2009-05-21 17:01:33 -0400315 error = -ENOMEM;
316 goto out_err;
317 }
318
319 /* convert the userspace DN_* "arg" to the internal FS_* defines in fsnotify */
320 mask = convert_arg(arg);
321
Eric Parisef5e2b72009-12-17 21:24:24 -0500322 /* set up the new_fsn_mark and new_dn_mark */
323 new_fsn_mark = &new_dn_mark->fsn_mark;
324 fsnotify_init_mark(new_fsn_mark, dnotify_free_mark);
325 new_fsn_mark->mask = mask;
326 new_dn_mark->dn = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400327
328 /* this is needed to prevent the fcntl/close race described below */
329 mutex_lock(&dnotify_mark_mutex);
330
Eric Parisef5e2b72009-12-17 21:24:24 -0500331 /* add the new_fsn_mark or find an old one. */
Eric Paris5444e292009-12-17 21:24:27 -0500332 fsn_mark = fsnotify_find_inode_mark(dnotify_group, inode);
Eric Parisef5e2b72009-12-17 21:24:24 -0500333 if (fsn_mark) {
334 dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
335 spin_lock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400336 } else {
Eric Paris5444e292009-12-17 21:24:27 -0500337 fsnotify_add_mark(new_fsn_mark, dnotify_group, inode, NULL, 0);
Eric Parisef5e2b72009-12-17 21:24:24 -0500338 spin_lock(&new_fsn_mark->lock);
339 fsn_mark = new_fsn_mark;
340 dn_mark = new_dn_mark;
341 /* we used new_fsn_mark, so don't free it */
342 new_fsn_mark = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400343 }
344
345 rcu_read_lock();
346 f = fcheck(fd);
347 rcu_read_unlock();
348
349 /* if (f != filp) means that we lost a race and another task/thread
350 * actually closed the fd we are still playing with before we grabbed
Eric Parisef5e2b72009-12-17 21:24:24 -0500351 * the dnotify_mark_mutex and fsn_mark->lock. Since closing the fd is the
Eric Parise61ce862009-12-17 21:24:24 -0500352 * only time we clean up the marks we need to get our mark off
Eric Paris3c5119c2009-05-21 17:01:33 -0400353 * the list. */
354 if (f != filp) {
355 /* if we added ourselves, shoot ourselves, it's possible that
Eric Parisef5e2b72009-12-17 21:24:24 -0500356 * the flush actually did shoot this fsn_mark. That's fine too
Eric Paris3c5119c2009-05-21 17:01:33 -0400357 * since multiple calls to destroy_mark is perfectly safe, if
Eric Parisef5e2b72009-12-17 21:24:24 -0500358 * we found a dn_mark already attached to the inode, just sod
Eric Paris3c5119c2009-05-21 17:01:33 -0400359 * off silently as the flush at close time dealt with it.
360 */
Eric Parisef5e2b72009-12-17 21:24:24 -0500361 if (dn_mark == new_dn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400362 destroy = 1;
363 goto out;
364 }
365
366 error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
367 if (error) {
368 /* if we added, we must shoot */
Eric Parisef5e2b72009-12-17 21:24:24 -0500369 if (dn_mark == new_dn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400370 destroy = 1;
371 goto out;
372 }
373
Eric Parisef5e2b72009-12-17 21:24:24 -0500374 error = attach_dn(dn, dn_mark, id, fd, filp, mask);
375 /* !error means that we attached the dn to the dn_mark, so don't free it */
Eric Paris3c5119c2009-05-21 17:01:33 -0400376 if (!error)
377 dn = NULL;
378 /* -EEXIST means that we didn't add this new dn and used an old one.
379 * that isn't an error (and the unused dn should be freed) */
380 else if (error == -EEXIST)
381 error = 0;
382
Eric Parisef5e2b72009-12-17 21:24:24 -0500383 dnotify_recalc_inode_mask(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400384out:
Eric Parisef5e2b72009-12-17 21:24:24 -0500385 spin_unlock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400386
387 if (destroy)
Lino Sanfilippoe2a29942011-06-14 17:29:51 +0200388 fsnotify_destroy_mark(fsn_mark, dnotify_group);
Eric Paris3c5119c2009-05-21 17:01:33 -0400389
Eric Paris3c5119c2009-05-21 17:01:33 -0400390 mutex_unlock(&dnotify_mark_mutex);
Eric Parisef5e2b72009-12-17 21:24:24 -0500391 fsnotify_put_mark(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400392out_err:
Eric Parisef5e2b72009-12-17 21:24:24 -0500393 if (new_fsn_mark)
394 fsnotify_put_mark(new_fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400395 if (dn)
396 kmem_cache_free(dnotify_struct_cache, dn);
397 return error;
398}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399
400static int __init dnotify_init(void)
401{
Eric Paris3c5119c2009-05-21 17:01:33 -0400402 dnotify_struct_cache = KMEM_CACHE(dnotify_struct, SLAB_PANIC);
Eric Parisef5e2b72009-12-17 21:24:24 -0500403 dnotify_mark_cache = KMEM_CACHE(dnotify_mark, SLAB_PANIC);
Eric Paris3c5119c2009-05-21 17:01:33 -0400404
Eric Paris0d2e2a12009-12-17 21:24:22 -0500405 dnotify_group = fsnotify_alloc_group(&dnotify_fsnotify_ops);
Eric Paris3c5119c2009-05-21 17:01:33 -0400406 if (IS_ERR(dnotify_group))
407 panic("unable to allocate fsnotify group for dnotify\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 return 0;
409}
410
411module_init(dnotify_init)