Datasec works in Linux kernel as a dynamic module for the file data protection. It can get a file extend name list and protect file in this pattern list through encoding the data stream from user to disk or decoding the data from disk to user automatically and transparently. When we switch this disk to another machin without right decoding module and right passport, the encoded data can not be recover to the useful format. Now it supports the Linux kernel 2.6.38 on desktop or mobile.