NTSTATUS
Ke386CallBios(
  IN  ULONG BiosCommand,
  IN OUT PCONTEXT BiosArguments
  );

Routine Description:

    This function invokes specified ROM BIOS code by executing
    "INT BiosCommand."  Before executing the BIOS code, this function
    will setup VDM context, change stack pointer ...etc.  If for some reason
    the operation fails, a status code will be returned.  Otherwise, this
    function always returns success regardless of the result of the BIOS
    call.

    N.B. This implementation relies on the fact that the direct
         I/O access operations between apps are serialized by win user.

Arguments:

    BiosCommand - Supplies which ROM BIOS function to invoke.

    BiosArguments - Supplies a pointer to the context which will be used
                    to invoke ROM BIOS.

Return Value:

    NTSTATUS code to specify the failure.