Zend File Upload Not Working – Troubleshooting Guide

I try to upload a file using Zend.

I made a standard form with a submit button which calls a controller.

In this controller, I have :

<?php
class Mine_Custoptiontypev5_UpfileController extends Mage_Core_Controller_Front_Action
{
    public function updatefileAction()
    {
        $post = $this->getRequest()->getPost();

    try {
            if (empty($post) || empty($_FILES)) {
                echo 'Invalid form data.';
                return $this;
            }

        $_order_id = $post['order_id'];
        $_item_id = $post['item_id'];
        $_option_id = $post['option_id'];
        $_action = $post['options_'.$_option_id.'_file_action'];

        $upload   = new Zend_File_Transfer_Adapter_Http();
        $file = 'options_' . $_option_id . '_file';

        $runValidation = $upload->isUploaded($file);
            if (!$runValidation) {
                return $this;
            }

        $fileInfo = $upload->getFileInfo($file);
        $fileInfo = $fileInfo[$file];
        $fileInfo['title'] = $fileInfo['name']; 

    }      
    catch (Exception $e) {
            // when file exceeds the upload_max_filesize, $_FILES is empty
            if (isset($_SERVER['CONTENT_LENGTH']) && $_SERVER['CONTENT_LENGTH'] > $this->_getUploadMaxFilesize()) {
                $_option->setIsValid(false);
                $value = $this->_bytesToMbytes($this->_getUploadMaxFilesize());
                Mage::throwException(
                    Mage::helper('catalog')->__("The file you uploaded is larger than %s Megabytes allowed by server", $value)
                );
            } 
        }

        /**
         * Option Validations
         */

        // Image dimensions
        $_dimentions = array();
        if ($_option->getImageSizeX() > 0) {
            $_dimentions['maxwidth'] = $_option->getImageSizeX();
        }
        if ($_option->getImageSizeY() > 0) {
            $_dimentions['maxheight'] = $_option->getImageSizeY();
        }
        if (count($_dimentions) > 0) {
            $upload->addValidator('ImageSize', false, $_dimentions);
        }

        // File extension
        $_allowed = $this->_parseExtensionsString($_option->getFileExtension());
        if ($_allowed !== null) {
            $upload->addValidator('Extension', false, $_allowed);           
        } 
        else {
            $_forbidden = $this->_parseExtensionsString(Mage::getModel('Mine_Custoptiontypev5_Model_Catalog_Product_Option_Type_Xfiletype')->getConfigData('forbidden_extensions'));
            if ($_forbidden !== null) {
                $upload->addValidator('ExcludeExtension', false, $_forbidden);
            }
        }

        // Maximum filesize
        $upload->addValidator('FilesSize', false, array('max' => $this->_getUploadMaxFilesize()));


         /**
         * Upload process
         */       

         $this->_initFilesystem();

        if ($upload->isUploaded($file) && $upload->isValid($file)) {

            $extension = pathinfo(strtolower($fileInfo['name']), PATHINFO_EXTENSION);

            $fileName = Mage_Core_Model_File_Uploader::getCorrectFileName($fileInfo['name']);
            $dispersion = Mage_Core_Model_File_Uploader::getDispretionPath($fileName);

            $filePath = $dispersion;
            $fileHash = md5(file_get_contents($fileInfo['tmp_name']));
            $filePath .= DS . $fileHash . '.' . $extension;
            $fileFullPath = $this->getQuoteTargetDir() . $filePath;

           $upload->addFilter('Rename', 
           array(
                'target' => $fileFullPath,
                'overwrite' => true
            ));

            try {
            $upload->receive();
            Zend_Debug::dump($upload->getFileInfo());}
            catch (Zend_File_Transfer_Exception $e) {
                Zend_Debug::dump($e->message());
            }
…

But my file is not moved to the desired destination path (../quote/x/x/xxxxxxxxxxxxx.xxx)

Could you help me please?