linux php 创建文件夹权限 上传文件的问题

$up_file_path=FILEPATH."movies/".$chid."/".$a;

	    echo $up_file_path."<br>";

	    if(is_dir($up_file_path)){

	        $up_file_path=$up_file_path;

	        chmod($up_file_path, 0777);

	    }

	    else {

	        @mkdir($up_file_path,0777);

	    }

这段代码在windows下使用正常，但是放到linux下面就不正常，提示：

A PHP Error was encountered

Severity: Warning

Message: mkdir(): Permission denied

Filename: libraries/Upload.php

Line Number: 708