ACPI_TABLE_DMAR
UINT32 Offset = sizeof (ACPI_TABLE_DMAR);
ACPI_TABLE_DMAR *dmar;
remaining = dmar->Header.Length - sizeof (ACPI_TABLE_DMAR);
#define ACPI_DMAR_OFFSET(f) (UINT16) ACPI_OFFSET (ACPI_TABLE_DMAR,f)