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);
+