ULONG
FASTCALL
MiMakeSystemAddressValidPfnWs(
  IN  PVOID VirtualAddress,
  IN  PEPROCESS CurrentProcess OPTIONAL
  );

Routine Description:

    This routine checks to see if the virtual address is valid, and if
    not makes it valid.

Arguments:

    VirtualAddress - Supplies the virtual address to make valid.

    CurrentProcess - Supplies a pointer to the current process, if the
                     working set lock is not held, this value is NULL.

Return Value:

    Returns TRUE if lock released and wait performed, FALSE otherwise.

Environment:

    Kernel mode, APCs disabled, PFN lock held, working set lock held
       if CurrentProcess != NULL.