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-rw-r--r--fs/notify/inotify/inotify_fsnotify.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
new file mode 100644
index 000000000000..7ef75b83247e
--- /dev/null
+++ b/fs/notify/inotify/inotify_fsnotify.c
@@ -0,0 +1,138 @@
1/*
2 * fs/inotify_user.c - inotify support for userspace
3 *
4 * Authors:
5 * John McCutchan <ttb@tentacle.dhs.org>
6 * Robert Love <rml@novell.com>
7 *
8 * Copyright (C) 2005 John McCutchan
9 * Copyright 2006 Hewlett-Packard Development Company, L.P.
10 *
11 * Copyright (C) 2009 Eric Paris <Red Hat Inc>
12 * inotify was largely rewriten to make use of the fsnotify infrastructure
13 *
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
17 * later version.
18 *
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.
23 */
24
25#include <linux/fs.h> /* struct inode */
26#include <linux/fsnotify_backend.h>
27#include <linux/inotify.h>
28#include <linux/path.h> /* struct path */
29#include <linux/slab.h> /* kmem_* */
30#include <linux/types.h>
31
32#include "inotify.h"
33
34static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event)
35{
36 struct fsnotify_mark_entry *entry;
37 struct inotify_inode_mark_entry *ientry;
38 struct inode *to_tell;
39 struct inotify_event_private_data *event_priv;
40 struct fsnotify_event_private_data *fsn_event_priv;
41 int wd, ret;
42
43 to_tell = event->to_tell;
44
45 spin_lock(&to_tell->i_lock);
46 entry = fsnotify_find_mark_entry(group, to_tell);
47 spin_unlock(&to_tell->i_lock);
48 /* race with watch removal? We already passes should_send */
49 if (unlikely(!entry))
50 return 0;
51 ientry = container_of(entry, struct inotify_inode_mark_entry,
52 fsn_entry);
53 wd = ientry->wd;
54
55 event_priv = kmem_cache_alloc(event_priv_cachep, GFP_KERNEL);
56 if (unlikely(!event_priv))
57 return -ENOMEM;
58
59 fsn_event_priv = &event_priv->fsnotify_event_priv_data;
60
61 fsn_event_priv->group = group;
62 event_priv->wd = wd;
63
64 ret = fsnotify_add_notify_event(group, event, fsn_event_priv);
65 /* EEXIST is not an error */
66 if (ret == -EEXIST)
67 ret = 0;
68
69 /* did event_priv get attached? */
70 if (list_empty(&fsn_event_priv->event_list))
71 inotify_free_event_priv(fsn_event_priv);
72
73 /*
74 * If we hold the entry until after the event is on the queue
75 * IN_IGNORED won't be able to pass this event in the queue
76 */
77 fsnotify_put_mark(entry);
78
79 return ret;
80}
81
82static void inotify_freeing_mark(struct fsnotify_mark_entry *entry, struct fsnotify_group *group)
83{
84 inotify_destroy_mark_entry(entry, group);
85}
86
87static bool inotify_should_send_event(struct fsnotify_group *group, struct inode *inode, __u32 mask)
88{
89 struct fsnotify_mark_entry *entry;
90 bool send;
91
92 spin_lock(&inode->i_lock);
93 entry = fsnotify_find_mark_entry(group, inode);
94 spin_unlock(&inode->i_lock);
95 if (!entry)
96 return false;
97
98 mask = (mask & ~FS_EVENT_ON_CHILD);
99 send = (entry->mask & mask);
100
101 /* find took a reference */
102 fsnotify_put_mark(entry);
103
104 return send;
105}
106
107static int idr_callback(int id, void *p, void *data)
108{
109 BUG();
110 return 0;
111}
112
113static void inotify_free_group_priv(struct fsnotify_group *group)
114{
115 /* ideally the idr is empty and we won't hit the BUG in teh callback */
116 idr_for_each(&group->inotify_data.idr, idr_callback, NULL);
117 idr_remove_all(&group->inotify_data.idr);
118 idr_destroy(&group->inotify_data.idr);
119}
120
121void inotify_free_event_priv(struct fsnotify_event_private_data *fsn_event_priv)
122{
123 struct inotify_event_private_data *event_priv;
124
125
126 event_priv = container_of(fsn_event_priv, struct inotify_event_private_data,
127 fsnotify_event_priv_data);
128
129 kmem_cache_free(event_priv_cachep, event_priv);
130}
131
132const struct fsnotify_ops inotify_fsnotify_ops = {
133 .handle_event = inotify_handle_event,
134 .should_send_event = inotify_should_send_event,
135 .free_group_priv = inotify_free_group_priv,
136 .free_event_priv = inotify_free_event_priv,
137 .freeing_mark = inotify_freeing_mark,
138};