NTSTATUS
HalpSetMountLetter(
  IN  PUNICODE_STRING DeviceName,
  IN  UCHAR           DriveLetter
  );

Routine Description:

    This routine sets the drive letter for the given device.

Arguments:

    DeviceName  - Supplies the device name.

    DriveLetter - Supplies the drive letter.

Return Value:

    NTSTATUS