A device, method, and machine-readable medium program product for controlling a tape data storage drive are disclosed. According to one embodiment, a device is provided for controlling a tape drive operable with a tape storage medium, the device comprising a buffer memory and a first functional unit. In the described embodiment, the first functional unit is configured to identify a logical end of the tape storage medium utilizing first data specifying a quantity of data stored within the buffer memory and second data specifying a current data write position on the tape storage medium.