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-rw-r--r--fs/notify/notification.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/fs/notify/notification.c b/fs/notify/notification.c
new file mode 100644
index 000000000000..b8e9a87f8f58
--- /dev/null
+++ b/fs/notify/notification.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2008 Red Hat, Inc., Eric Paris <eparis@redhat.com>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/mount.h>
+#include <linux/mutex.h>
+#include <linux/namei.h>
+#include <linux/path.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include <asm/atomic.h>
+
+#include <linux/fsnotify_backend.h>
+#include "fsnotify.h"
+
+static struct kmem_cache *fsnotify_event_cachep;
+
+void fsnotify_get_event(struct fsnotify_event *event)
+{
+ atomic_inc(&event->refcnt);
+}
+
+void fsnotify_put_event(struct fsnotify_event *event)
+{
+ if (!event)
+ return;
+
+ if (atomic_dec_and_test(&event->refcnt)) {
+ if (event->data_type == FSNOTIFY_EVENT_PATH)
+ path_put(&event->path);
+
+ kmem_cache_free(fsnotify_event_cachep, event);
+ }
+}
+
+/*
+ * Allocate a new event which will be sent to each group's handle_event function
+ * if the group was interested in this particular event.
+ */
+struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u32 mask,
+ void *data, int data_type)
+{
+ struct fsnotify_event *event;
+
+ event = kmem_cache_alloc(fsnotify_event_cachep, GFP_KERNEL);
+ if (!event)
+ return NULL;
+
+ atomic_set(&event->refcnt, 1);
+
+ spin_lock_init(&event->lock);
+
+ event->path.dentry = NULL;
+ event->path.mnt = NULL;
+ event->inode = NULL;
+
+ event->to_tell = to_tell;
+
+ switch (data_type) {
+ case FSNOTIFY_EVENT_FILE: {
+ struct file *file = data;
+ struct path *path = &file->f_path;
+ event->path.dentry = path->dentry;
+ event->path.mnt = path->mnt;
+ path_get(&event->path);
+ event->data_type = FSNOTIFY_EVENT_PATH;
+ break;
+ }
+ case FSNOTIFY_EVENT_PATH: {
+ struct path *path = data;
+ event->path.dentry = path->dentry;
+ event->path.mnt = path->mnt;
+ path_get(&event->path);
+ event->data_type = FSNOTIFY_EVENT_PATH;
+ break;
+ }
+ case FSNOTIFY_EVENT_INODE:
+ event->inode = data;
+ event->data_type = FSNOTIFY_EVENT_INODE;
+ break;
+ case FSNOTIFY_EVENT_NONE:
+ event->inode = NULL;
+ event->path.dentry = NULL;
+ event->path.mnt = NULL;
+ break;
+ default:
+ BUG();
+ }
+
+ event->mask = mask;
+
+ return event;
+}
+
+__init int fsnotify_notification_init(void)
+{
+ fsnotify_event_cachep = KMEM_CACHE(fsnotify_event, SLAB_PANIC);
+
+ return 0;
+}
+subsys_initcall(fsnotify_notification_init);
+