Файл изображения CodeIgniter не может быть загружен

Единственная проблема, которую я не могу решить в течение времени, я попробовал все возможные решения, но у меня не получается
Ну, проблема в том, что когда я хочу загрузить изображение, я выбираю изображение из своего компа, и когда я нажимаю кнопку отправки, изображение не загружается, и оно показывает мне дефолтное изображение, которое я помещаю в случае, если пользователь не выбирает изображение ( noimage.jpg)
Функция запуска загрузки изображения в методе create ()

Контроллер сообщений

<?phpclass Posts extends CI_Controller{

public function __construct(){
parent::__construct();
$this->load->database();
$this->load->library('upload');

}

public function index($offset = 0){$config['base_url'] = base_url() . 'posts/index/';
$config['total_rows'] = $this->db->count_all('posts');
$config['per_page'] = 3;
$config['uri_segment'] = 3;
$config['attributes'] = array('class' => 'pagination-link');

$this->pagination->initialize($config);

$data['posts']= $this->Posts_model->get_posts(FALSE,$config['per_page'],$offset);

$this->load->view('templates/header');
$this->load->view('posts/index',$data);
$this->load->view('templates/footer');}public function view($mjestoOdredista=NULL){$data['posts'] = $this->Posts_model->get_posts($mjestoOdredista);
$post_id = $data['posts']['id'];
$data['comments'] = $this->comment_model->get_comments($post_id);

if(empty($data['posts'])){
show_404();
}
$data['id'] =$data['posts'];

$this->load->view('templates/header');
$this->load->view('posts/view',$data);
$this->load->view('templates/footer');}public function create(){
//check if user is logged in
if(!$this->session->userdata('logged_in')){
redirect('users/login');
}

$this->form_validation->set_rules('mjestoPolaska', 'Mjesto Polaska', 'required');
$this->form_validation->set_rules('mjestoOdredista', 'Mjesto Odredista', 'required');
$this->form_validation->set_rules('datumPolaska', 'Datum Polaska', 'required');
$this->form_validation->set_rules('datumPovratka', 'Datum Povratka', 'required');
$this->form_validation->set_rules('cijena', 'Cijena', 'required');
$this->form_validation->set_rules('brojMjesta', 'Broj mjesta', 'required');
$this->form_validation->set_rules('opis', 'Opis', 'required');$data['title'] ='Create Posts';
$data['categories'] = $this->Posts_model->get_categories();

if($this->form_validation->run()===FALSE){

$this->load->view('templates/header');
$this->load->view('posts/create',$data);
$this->load->view('templates/footer');

}else {

//upload image
$config['upload_path'] = './assets/images/posts';
$config['allowed_types'] = 'gif|jpg|png';
$config['max_size'] = '2048';
$config['max_width'] = '100';
$config['max_height'] = '100';

$this->load->library('upload',$config);if(!$this->upload->do_upload('userfile')){
$errors = array('error'=>$this->upload->display_errors());
$post_image='noimage.jpg';
}else{
$data = array('upload_data'=>$this->upload->data());
$post_image = $_FILES['userfile']['name'];
}
$this->Posts_model->create_post($post_image);
$this->session->set_flashdata('post_creted', 'You post has been created') ;
redirect('posts');
}

}

public function delete($id){

if(!$this->session->userdata('logged_in')){
redirect('users/login');
}$this->Posts_model->delete_post($id);
$this->session->set_flashdata('post_deleted', 'You post has been deleted  ') ;
redirect('posts');
}public function edit($mjestoOdredista){
if(!$this->session->userdata('logged_in')){
redirect('users/login');
}

$data['posts']= $this->Posts_model->get_posts($mjestoOdredista);

//Check if user is logged in
if($this->session->userdata('user_id') != $this->Posts_model->get_posts($mjestoOdredista)['user_id']){
redirect('posts');
}

$data['categories'] = $this->Posts_model->get_categories();

if(empty($data['posts'])){
show_404();
}

$data['title'] = 'Edit Post';
$this->load->view('templates/header');
$this->load->view('posts/edit',$data);
$this->load->view('templates/footer');
}public function update(){
if(!$this->session->userdata('logged_in')){
redirect('users/login');
}

$this->Posts_model->update_post();
$this->session->set_flashdata('post_updated', 'You post has been updated ') ;
redirect('posts');

}

}

?>

Posts_model

<?phpclass Posts_Model extends CI_Model{

public function __construct(){
$this->load->database();

}

function get_posts($mjestoOdredista=FALSE, $limit = FALSE,$offset = FALSE){
if($limit){
$this->db->limit($limit,$offset);
}
if($mjestoOdredista === FALSE){

$this->db->order_by('posts.id','DESC');
$this->db->join('categories','categories.id = posts.category_id');
$query=$this->db->get('posts');
return $query->result_array();
}

$query=$this->db->get_where('posts', array('mjestoOdredista' => $mjestoOdredista));return $query->row_array();
}

//Kreiranje post
public function create_post($post_image){
$mjestoPolaska = url_title($this->input->post('title'));
$data=array(
'mjestoPolaska' => $this->input->post('mjestoPolaska'),
'mjestoOdredista' => $this->input ->post('mjestoOdredista'),
'datumPolaska' => $this->input ->post('datumPolaska'),
'datumPovratka' => $this->input ->post('datumPovratka'),
'brojMjesta' => $this->input ->post('brojMjesta'),
'cijena' => $this->input ->post('cijena'),
'opis' => $this->input ->post('opis'),
'category_id'=>$this->input->post('category_id'),
'user_id' =>$this->session->userdata('user_id'),
'post_image'=>$post_image

);

return $this->db->insert('posts',$data);
}

//Brisanje posta
public function delete_post($id){
$this->db->where('id',$id);
$this->db->delete('posts');
return true;
}//editovanje posta
public function update_post(){
$mjestoOdredista = url_title($this->input->post('title'));
$data=array(
'category_id' => $this->input->post('category_id'),
'mjestoPolaska' =>   $this->input->post('mjestoPolaska'),
'mjestoOdredista' => $this->input->post('mjestoOdredista'),
'datumPolaska' =>    $this->input ->post('datumPolaska'),
'datumPovratka' =>   $this->input ->post('datumPovratka'),
'cijena' =>          $this->input ->post('cijena'),
'brojMjesta' =>      $this->input ->post('brojMjesta'),
'opis' =>            $this->input ->post('opis'),

);
$this->db->where('id', $this->input->post('id'));
return $this->db->update('posts', $data);

}

public function get_categories(){
$this->db->order_by('name');
$query = $this->db->get('categories');
return $query->result_array();
}

public function get_posts_by_category($category_id){

$this->db->order_by('posts.id','DESC');

$this->db->join('categories','categories.id = posts.category_id');
$query=$this->db->get_where('posts',array('category_id'=>   $category_id));
return $query->result_array();

}}?>

Создать вид

<h2><?= $title;?></h2>
<link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css">
<link rel="stylesheet" href="/resources/demos/style.css">
<script src="https://code.jquery.com/jquery-1.12.4.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>

<script>
$( function() {
$("#datepicker").datepicker({
dateFormat: 'dd-mm-yy'
});
$("#datepicker1").datepicker({
dateFormat: 'dd-mm-yy'
});
});
</script><?php echo form_open_multipart('posts/create/');?>
<?php echo validation_errors();?>

<div class="row">
<div class="col-md-4 col-md-offset-4">

<div class="form-group">
<label>Mjesto Polaska</label>
<input type="text" class="form-control" name="mjestoPolaska" placeholder="Mjesto Polaska">
</div><div class="form-group">
<label>Mjesto Odredista</label>
<input type="text" class="form-control" name="mjestoOdredista" placeholder="Mjesto Odredista">
</div>

<div class="form-group">
<label>Datum Polaska</label>
<input type="date" id="datepicker" class="form-control" name="datumPolaska" placeholder ="Datum Polaska" >
</div>

<div class="form-group">
<label>Datum Povratka</label>
<input type="date" id="datepicker1" class="form-control" name="datumPovratka" placeholder="Datum Povratka">
</div><div class="form-group">
<label>Cijena</label>
<input type="text" class="form-control" name="cijena" placeholder="Cijena">
</div>

<div class="form-group">
<label for="select">Broj slobodnih mjesta</label>
<select class="form-control" id="select" name="brojMjesta">
<option>1</option>
<option>2</option>
<option>3</option>
<option>4</option>
</select>
</div><div class="form-group">
<label for="kategorije">Kategorija</label>
<?php
echo '<select class="form-control" id="kategorije" name="category_id">';
foreach($categories as $category) :
echo '<option value="' . $category['id'] . '">' . $category["name"] . '</option>';
endforeach;
echo '</select>';
?>
</div>

<div class="form-group">
<label>Postavi sliku:</label>
<p><b>samo oni koji nude prevoz nek postave sliku svojeg vozila</b></p>
<input type="file" name="userfile" size="20">
</div>

<div class="form-group">
<label>Opis:</label>
<textarea class="form-control" rows="5" id="comment" name="opis"></textarea>
</div>
<button type="submit" class="btn btn-primary btn-block">Submit</button>

</div>
</div>