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Diffstat (limited to 'fs/notify/inotify/inotify_fsnotify.c')
-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 @@
+/*
+ * fs/inotify_user.c - inotify support for userspace
+ *
+ * Authors:
+ * John McCutchan <ttb@tentacle.dhs.org>
+ * Robert Love <rml@novell.com>
+ *
+ * Copyright (C) 2005 John McCutchan
+ * Copyright 2006 Hewlett-Packard Development Company, L.P.
+ *
+ * Copyright (C) 2009 Eric Paris <Red Hat Inc>
+ * inotify was largely rewriten to make use of the fsnotify infrastructure
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/fs.h> /* struct inode */
+#include <linux/fsnotify_backend.h>
+#include <linux/inotify.h>
+#include <linux/path.h> /* struct path */
+#include <linux/slab.h> /* kmem_* */
+#include <linux/types.h>
+
+#include "inotify.h"
+
+static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event)
+{
+ struct fsnotify_mark_entry *entry;
+ struct inotify_inode_mark_entry *ientry;
+ struct inode *to_tell;
+ struct inotify_event_private_data *event_priv;
+ struct fsnotify_event_private_data *fsn_event_priv;
+ int wd, ret;
+
+ to_tell = event->to_tell;
+
+ spin_lock(&to_tell->i_lock);
+ entry = fsnotify_find_mark_entry(group, to_tell);
+ spin_unlock(&to_tell->i_lock);
+ /* race with watch removal? We already passes should_send */
+ if (unlikely(!entry))
+ return 0;
+ ientry = container_of(entry, struct inotify_inode_mark_entry,
+ fsn_entry);
+ wd = ientry->wd;
+
+ event_priv = kmem_cache_alloc(event_priv_cachep, GFP_KERNEL);
+ if (unlikely(!event_priv))
+ return -ENOMEM;
+
+ fsn_event_priv = &event_priv->fsnotify_event_priv_data;
+
+ fsn_event_priv->group = group;
+ event_priv->wd = wd;
+
+ ret = fsnotify_add_notify_event(group, event, fsn_event_priv);
+ /* EEXIST is not an error */
+ if (ret == -EEXIST)
+ ret = 0;
+
+ /* did event_priv get attached? */
+ if (list_empty(&fsn_event_priv->event_list))
+ inotify_free_event_priv(fsn_event_priv);
+
+ /*
+ * If we hold the entry until after the event is on the queue
+ * IN_IGNORED won't be able to pass this event in the queue
+ */
+ fsnotify_put_mark(entry);
+
+ return ret;
+}
+
+static void inotify_freeing_mark(struct fsnotify_mark_entry *entry, struct fsnotify_group *group)
+{
+ inotify_destroy_mark_entry(entry, group);
+}
+
+static bool inotify_should_send_event(struct fsnotify_group *group, struct inode *inode, __u32 mask)
+{
+ struct fsnotify_mark_entry *entry;
+ bool send;
+
+ spin_lock(&inode->i_lock);
+ entry = fsnotify_find_mark_entry(group, inode);
+ spin_unlock(&inode->i_lock);
+ if (!entry)
+ return false;
+
+ mask = (mask & ~FS_EVENT_ON_CHILD);
+ send = (entry->mask & mask);
+
+ /* find took a reference */
+ fsnotify_put_mark(entry);
+
+ return send;
+}
+
+static int idr_callback(int id, void *p, void *data)
+{
+ BUG();
+ return 0;
+}
+
+static void inotify_free_group_priv(struct fsnotify_group *group)
+{
+ /* ideally the idr is empty and we won't hit the BUG in teh callback */
+ idr_for_each(&group->inotify_data.idr, idr_callback, NULL);
+ idr_remove_all(&group->inotify_data.idr);
+ idr_destroy(&group->inotify_data.idr);
+}
+
+void inotify_free_event_priv(struct fsnotify_event_private_data *fsn_event_priv)
+{
+ struct inotify_event_private_data *event_priv;
+
+
+ event_priv = container_of(fsn_event_priv, struct inotify_event_private_data,
+ fsnotify_event_priv_data);
+
+ kmem_cache_free(event_priv_cachep, event_priv);
+}
+
+const struct fsnotify_ops inotify_fsnotify_ops = {
+ .handle_event = inotify_handle_event,
+ .should_send_event = inotify_should_send_event,
+ .free_group_priv = inotify_free_group_priv,
+ .free_event_priv = inotify_free_event_priv,
+ .freeing_mark = inotify_freeing_mark,
+};