blob: c3dc15879a520b239d005c555cd07066fef9ecb1 [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 Paris3a9b16b2010-07-28 10:18:38 -040086 struct fsnotify_mark *mark,
Eric Paris3c5119c2009-05-21 17:01:33 -040087 struct fsnotify_event *event)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088{
Eric Parisef5e2b72009-12-17 21:24:24 -050089 struct dnotify_mark *dn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -040090 struct inode *to_tell;
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 struct dnotify_struct *dn;
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 struct dnotify_struct **prev;
Eric Paris3c5119c2009-05-21 17:01:33 -040093 struct fown_struct *fown;
Andreas Gruenbacher94552682009-10-15 00:13:23 +020094 __u32 test_mask = event->mask & ~FS_EVENT_ON_CHILD;
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
Eric Paris3c5119c2009-05-21 17:01:33 -040096 to_tell = event->to_tell;
97
Eric Parisc4963132010-07-28 10:18:38 -040098 dn_mark = container_of(mark, struct dnotify_mark, fsn_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
Eric Parisc4963132010-07-28 10:18:38 -0400100 spin_lock(&mark->lock);
Eric Parisef5e2b72009-12-17 21:24:24 -0500101 prev = &dn_mark->dn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 while ((dn = *prev) != NULL) {
Andreas Gruenbacher94552682009-10-15 00:13:23 +0200103 if ((dn->dn_mask & test_mask) == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 prev = &dn->dn_next;
105 continue;
106 }
107 fown = &dn->dn_filp->f_owner;
108 send_sigio(fown, dn->dn_fd, POLL_MSG);
Eric Paris3c5119c2009-05-21 17:01:33 -0400109 if (dn->dn_mask & FS_DN_MULTISHOT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 prev = &dn->dn_next;
111 else {
112 *prev = dn->dn_next;
Eric Paris3c5119c2009-05-21 17:01:33 -0400113 kmem_cache_free(dnotify_struct_cache, dn);
Eric Parisc4963132010-07-28 10:18:38 -0400114 dnotify_recalc_inode_mask(mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 }
116 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117
Eric Parisc4963132010-07-28 10:18:38 -0400118 spin_unlock(&mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400119
120 return 0;
121}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122
123/*
Eric Paris3c5119c2009-05-21 17:01:33 -0400124 * Given an inode and mask determine if dnotify would be interested in sending
125 * userspace notification for that pair.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 */
Eric Paris3c5119c2009-05-21 17:01:33 -0400127static bool dnotify_should_send_event(struct fsnotify_group *group,
Eric Paris3a9fb892009-12-17 21:24:23 -0500128 struct inode *inode, struct vfsmount *mnt,
Eric Paris3a9b16b2010-07-28 10:18:38 -0400129 struct fsnotify_mark *mark, __u32 mask,
130 void *data, int data_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131{
Eric Paris3c5119c2009-05-21 17:01:33 -0400132 /* not a dir, dnotify doesn't care */
133 if (!S_ISDIR(inode->i_mode))
134 return false;
135
Eric Paris2612abb2010-07-28 10:18:39 -0400136 return true;
Eric Paris3c5119c2009-05-21 17:01:33 -0400137}
138
Eric Parisef5e2b72009-12-17 21:24:24 -0500139static void dnotify_free_mark(struct fsnotify_mark *fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400140{
Eric Parisef5e2b72009-12-17 21:24:24 -0500141 struct dnotify_mark *dn_mark = container_of(fsn_mark,
142 struct dnotify_mark,
143 fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400144
Eric Parisef5e2b72009-12-17 21:24:24 -0500145 BUG_ON(dn_mark->dn);
Eric Paris3c5119c2009-05-21 17:01:33 -0400146
Eric Parisef5e2b72009-12-17 21:24:24 -0500147 kmem_cache_free(dnotify_mark_cache, dn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400148}
149
150static struct fsnotify_ops dnotify_fsnotify_ops = {
151 .handle_event = dnotify_handle_event,
152 .should_send_event = dnotify_should_send_event,
153 .free_group_priv = NULL,
Eric Parisa092ee22009-06-11 11:09:48 -0400154 .freeing_mark = NULL,
Eric Parise4aff112009-05-21 17:01:50 -0400155 .free_event_priv = NULL,
Eric Paris3c5119c2009-05-21 17:01:33 -0400156};
157
158/*
159 * Called every time a file is closed. Looks first for a dnotify mark on the
Eric Parise61ce862009-12-17 21:24:24 -0500160 * inode. If one is found run all of the ->dn structures attached to that
Eric Paris3c5119c2009-05-21 17:01:33 -0400161 * mark for one relevant to this process closing the file and remove that
162 * dnotify_struct. If that was the last dnotify_struct also remove the
Eric Parise61ce862009-12-17 21:24:24 -0500163 * fsnotify_mark.
Eric Paris3c5119c2009-05-21 17:01:33 -0400164 */
165void dnotify_flush(struct file *filp, fl_owner_t id)
166{
Eric Parisef5e2b72009-12-17 21:24:24 -0500167 struct fsnotify_mark *fsn_mark;
168 struct dnotify_mark *dn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -0400169 struct dnotify_struct *dn;
170 struct dnotify_struct **prev;
171 struct inode *inode;
172
173 inode = filp->f_path.dentry->d_inode;
174 if (!S_ISDIR(inode->i_mode))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 return;
176
Eric Paris5444e292009-12-17 21:24:27 -0500177 fsn_mark = fsnotify_find_inode_mark(dnotify_group, inode);
Eric Parisef5e2b72009-12-17 21:24:24 -0500178 if (!fsn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400179 return;
Eric Parisef5e2b72009-12-17 21:24:24 -0500180 dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400181
182 mutex_lock(&dnotify_mark_mutex);
183
Eric Parisef5e2b72009-12-17 21:24:24 -0500184 spin_lock(&fsn_mark->lock);
185 prev = &dn_mark->dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400186 while ((dn = *prev) != NULL) {
187 if ((dn->dn_owner == id) && (dn->dn_filp == filp)) {
188 *prev = dn->dn_next;
189 kmem_cache_free(dnotify_struct_cache, dn);
Eric Parisef5e2b72009-12-17 21:24:24 -0500190 dnotify_recalc_inode_mask(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400191 break;
192 }
193 prev = &dn->dn_next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 }
Eric Paris3c5119c2009-05-21 17:01:33 -0400195
Eric Parisef5e2b72009-12-17 21:24:24 -0500196 spin_unlock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400197
198 /* nothing else could have found us thanks to the dnotify_mark_mutex */
Eric Parisef5e2b72009-12-17 21:24:24 -0500199 if (dn_mark->dn == NULL)
200 fsnotify_destroy_mark(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400201
202 fsnotify_recalc_group_mask(dnotify_group);
203
204 mutex_unlock(&dnotify_mark_mutex);
205
Eric Parisef5e2b72009-12-17 21:24:24 -0500206 fsnotify_put_mark(fsn_mark);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207}
Eric Paris3c5119c2009-05-21 17:01:33 -0400208
209/* this conversion is done only at watch creation */
210static __u32 convert_arg(unsigned long arg)
211{
212 __u32 new_mask = FS_EVENT_ON_CHILD;
213
214 if (arg & DN_MULTISHOT)
215 new_mask |= FS_DN_MULTISHOT;
216 if (arg & DN_DELETE)
217 new_mask |= (FS_DELETE | FS_MOVED_FROM);
218 if (arg & DN_MODIFY)
219 new_mask |= FS_MODIFY;
220 if (arg & DN_ACCESS)
221 new_mask |= FS_ACCESS;
222 if (arg & DN_ATTRIB)
223 new_mask |= FS_ATTRIB;
224 if (arg & DN_RENAME)
225 new_mask |= FS_DN_RENAME;
226 if (arg & DN_CREATE)
227 new_mask |= (FS_CREATE | FS_MOVED_TO);
228
229 return new_mask;
230}
231
232/*
233 * If multiple processes watch the same inode with dnotify there is only one
Eric Parise61ce862009-12-17 21:24:24 -0500234 * dnotify mark in inode->i_fsnotify_marks but we chain a dnotify_struct
Eric Paris3c5119c2009-05-21 17:01:33 -0400235 * onto that mark. This function either attaches the new dnotify_struct onto
236 * that list, or it |= the mask onto an existing dnofiy_struct.
237 */
Eric Parisef5e2b72009-12-17 21:24:24 -0500238static int attach_dn(struct dnotify_struct *dn, struct dnotify_mark *dn_mark,
Eric Paris3c5119c2009-05-21 17:01:33 -0400239 fl_owner_t id, int fd, struct file *filp, __u32 mask)
240{
241 struct dnotify_struct *odn;
242
Eric Parisef5e2b72009-12-17 21:24:24 -0500243 odn = dn_mark->dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400244 while (odn != NULL) {
245 /* adding more events to existing dnofiy_struct? */
246 if ((odn->dn_owner == id) && (odn->dn_filp == filp)) {
247 odn->dn_fd = fd;
248 odn->dn_mask |= mask;
249 return -EEXIST;
250 }
251 odn = odn->dn_next;
252 }
253
254 dn->dn_mask = mask;
255 dn->dn_fd = fd;
256 dn->dn_filp = filp;
257 dn->dn_owner = id;
Eric Parisef5e2b72009-12-17 21:24:24 -0500258 dn->dn_next = dn_mark->dn;
259 dn_mark->dn = dn;
Eric Paris3c5119c2009-05-21 17:01:33 -0400260
261 return 0;
262}
263
264/*
265 * When a process calls fcntl to attach a dnotify watch to a directory it ends
266 * up here. Allocate both a mark for fsnotify to add and a dnotify_struct to be
267 * attached to the fsnotify_mark.
268 */
269int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
270{
Eric Parisef5e2b72009-12-17 21:24:24 -0500271 struct dnotify_mark *new_dn_mark, *dn_mark;
272 struct fsnotify_mark *new_fsn_mark, *fsn_mark;
Eric Paris3c5119c2009-05-21 17:01:33 -0400273 struct dnotify_struct *dn;
274 struct inode *inode;
275 fl_owner_t id = current->files;
276 struct file *f;
277 int destroy = 0, error = 0;
278 __u32 mask;
279
280 /* we use these to tell if we need to kfree */
Eric Parisef5e2b72009-12-17 21:24:24 -0500281 new_fsn_mark = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400282 dn = NULL;
283
284 if (!dir_notify_enable) {
285 error = -EINVAL;
286 goto out_err;
287 }
288
289 /* a 0 mask means we are explicitly removing the watch */
290 if ((arg & ~DN_MULTISHOT) == 0) {
291 dnotify_flush(filp, id);
292 error = 0;
293 goto out_err;
294 }
295
296 /* dnotify only works on directories */
297 inode = filp->f_path.dentry->d_inode;
298 if (!S_ISDIR(inode->i_mode)) {
299 error = -ENOTDIR;
300 goto out_err;
301 }
302
303 /* expect most fcntl to add new rather than augment old */
304 dn = kmem_cache_alloc(dnotify_struct_cache, GFP_KERNEL);
305 if (!dn) {
306 error = -ENOMEM;
307 goto out_err;
308 }
309
310 /* new fsnotify mark, we expect most fcntl calls to add a new mark */
Eric Parisef5e2b72009-12-17 21:24:24 -0500311 new_dn_mark = kmem_cache_alloc(dnotify_mark_cache, GFP_KERNEL);
312 if (!new_dn_mark) {
Eric Paris3c5119c2009-05-21 17:01:33 -0400313 error = -ENOMEM;
314 goto out_err;
315 }
316
317 /* convert the userspace DN_* "arg" to the internal FS_* defines in fsnotify */
318 mask = convert_arg(arg);
319
Eric Parisef5e2b72009-12-17 21:24:24 -0500320 /* set up the new_fsn_mark and new_dn_mark */
321 new_fsn_mark = &new_dn_mark->fsn_mark;
322 fsnotify_init_mark(new_fsn_mark, dnotify_free_mark);
323 new_fsn_mark->mask = mask;
324 new_dn_mark->dn = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400325
326 /* this is needed to prevent the fcntl/close race described below */
327 mutex_lock(&dnotify_mark_mutex);
328
Eric Parisef5e2b72009-12-17 21:24:24 -0500329 /* add the new_fsn_mark or find an old one. */
Eric Paris5444e292009-12-17 21:24:27 -0500330 fsn_mark = fsnotify_find_inode_mark(dnotify_group, inode);
Eric Parisef5e2b72009-12-17 21:24:24 -0500331 if (fsn_mark) {
332 dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
333 spin_lock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400334 } else {
Eric Paris5444e292009-12-17 21:24:27 -0500335 fsnotify_add_mark(new_fsn_mark, dnotify_group, inode, NULL, 0);
Eric Parisef5e2b72009-12-17 21:24:24 -0500336 spin_lock(&new_fsn_mark->lock);
337 fsn_mark = new_fsn_mark;
338 dn_mark = new_dn_mark;
339 /* we used new_fsn_mark, so don't free it */
340 new_fsn_mark = NULL;
Eric Paris3c5119c2009-05-21 17:01:33 -0400341 }
342
343 rcu_read_lock();
344 f = fcheck(fd);
345 rcu_read_unlock();
346
347 /* if (f != filp) means that we lost a race and another task/thread
348 * actually closed the fd we are still playing with before we grabbed
Eric Parisef5e2b72009-12-17 21:24:24 -0500349 * the dnotify_mark_mutex and fsn_mark->lock. Since closing the fd is the
Eric Parise61ce862009-12-17 21:24:24 -0500350 * only time we clean up the marks we need to get our mark off
Eric Paris3c5119c2009-05-21 17:01:33 -0400351 * the list. */
352 if (f != filp) {
353 /* if we added ourselves, shoot ourselves, it's possible that
Eric Parisef5e2b72009-12-17 21:24:24 -0500354 * the flush actually did shoot this fsn_mark. That's fine too
Eric Paris3c5119c2009-05-21 17:01:33 -0400355 * since multiple calls to destroy_mark is perfectly safe, if
Eric Parisef5e2b72009-12-17 21:24:24 -0500356 * we found a dn_mark already attached to the inode, just sod
Eric Paris3c5119c2009-05-21 17:01:33 -0400357 * off silently as the flush at close time dealt with it.
358 */
Eric Parisef5e2b72009-12-17 21:24:24 -0500359 if (dn_mark == new_dn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400360 destroy = 1;
361 goto out;
362 }
363
364 error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
365 if (error) {
366 /* if we added, we must shoot */
Eric Parisef5e2b72009-12-17 21:24:24 -0500367 if (dn_mark == new_dn_mark)
Eric Paris3c5119c2009-05-21 17:01:33 -0400368 destroy = 1;
369 goto out;
370 }
371
Eric Parisef5e2b72009-12-17 21:24:24 -0500372 error = attach_dn(dn, dn_mark, id, fd, filp, mask);
373 /* !error means that we attached the dn to the dn_mark, so don't free it */
Eric Paris3c5119c2009-05-21 17:01:33 -0400374 if (!error)
375 dn = NULL;
376 /* -EEXIST means that we didn't add this new dn and used an old one.
377 * that isn't an error (and the unused dn should be freed) */
378 else if (error == -EEXIST)
379 error = 0;
380
Eric Parisef5e2b72009-12-17 21:24:24 -0500381 dnotify_recalc_inode_mask(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400382out:
Eric Parisef5e2b72009-12-17 21:24:24 -0500383 spin_unlock(&fsn_mark->lock);
Eric Paris3c5119c2009-05-21 17:01:33 -0400384
385 if (destroy)
Eric Parisef5e2b72009-12-17 21:24:24 -0500386 fsnotify_destroy_mark(fsn_mark);
Eric Paris3c5119c2009-05-21 17:01:33 -0400387
388 fsnotify_recalc_group_mask(dnotify_group);
389
390 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)