อยากกำหนดให้ UPLOAD รูปให้ไม่เกิน 9 รูปต้องใส่เงื่อนไขเพิ่มยังไงครับ

public function file_upload(){
              $files = $_FILES;
              $count = count($_FILES['userfile']['name']);
              for($i=0; $i<$count; $i++)
                {
                $_FILES['userfile']['name']= time().$files['userfile']['name'][$i];
                $_FILES['userfile']['type']= $files['userfile']['type'][$i];
                $_FILES['userfile']['tmp_name']= $files['userfile']['tmp_name'][$i];
                $_FILES['userfile']['error']= $files['userfile']['error'][$i];
                $_FILES['userfile']['size']= $files['userfile']['size'][$i];
                $config['upload_path'] = './uploads/';
                $config['allowed_types'] = 'gif|jpg|png|jpeg';
                $config['max_size'] = '2000000';
                $config['remove_spaces'] = true;
                $config['overwrite'] = false;
                $config['max_width'] = '';
                $config['max_height'] = '';
                $this->load->library('upload', $config);
                $this->upload->initialize($config);
                $this->upload->do_upload();
                $fileName = $_FILES['userfile']['name'];
                $images[] = $fileName;
				}
				  $fileName = implode(',',$images);
				  $this->welcome->upload_image($this->input->post(),$fileName);
				  redirect('welcome/view');
				}