[PATCH] kobject_add_dir

Adding kobject_add_dir() function which creates a subdirectory
for a given kobject.
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

include/linux/kobject.h

@@ -80,6 +80,8 @@ extern void kobject_unregister(struct kobject *);
 extern struct kobject * kobject_get(struct kobject *);
 extern void kobject_put(struct kobject *);
 
+extern struct kobject *kobject_add_dir(struct kobject *, const char *);
+
 extern char * kobject_get_path(struct kobject *, gfp_t);
 
 struct kobj_type {

lib/kobject.c

@@ -385,6 +385,44 @@ void kobject_put(struct kobject * kobj)
 }
 
 
+static void dir_release(struct kobject *kobj)
+{
+	kfree(kobj);
+}
+
+static struct kobj_type dir_ktype = {
+	.release	= dir_release,
+	.sysfs_ops	= NULL,
+	.default_attrs	= NULL,
+};
+
+/**
+ *	kobject_add_dir - add sub directory of object.
+ *	@parent:	object in which a directory is created.
+ *	@name:	directory name.
+ *
+ *	Add a plain directory object as child of given object.
+ */
+struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
+{
+	struct kobject *k;
+
+	if (!parent)
+		return NULL;
+
+	k = kzalloc(sizeof(*k), GFP_KERNEL);
+	if (!k)
+		return NULL;
+
+	k->parent = parent;
+	k->ktype = &dir_ktype;
+	kobject_set_name(k, name);
+	kobject_register(k);
+
+	return k;
+}
+EXPORT_SYMBOL_GPL(kobject_add_dir);
+
 /**
  *	kset_init - initialize a kset for use
  *	@k:	kset