quotactl_block(): switch to CLASS(filename)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Author: Al Viro

fs/quota/quota.c

@@ -867,15 +867,14 @@ static struct super_block *quotactl_block(const char __user *special, int cmd)
 {
 #ifdef CONFIG_BLOCK
 	struct super_block *sb;
-	struct filename *tmp = getname(special);
+	CLASS(filename, tmp)(special);
 	bool excl = false, thawed = false;
 	int error;
 	dev_t dev;
 
 	if (IS_ERR(tmp))
 		return ERR_CAST(tmp);
 	error = lookup_bdev(tmp->name, &dev);
-	putname(tmp);
 	if (error)
 		return ERR_PTR(error);