typedef struct _IO_RESOURCE_REQUIREMENTS_LIST
{
     ULONG ListSize;
     INTERFACE_TYPE InterfaceType;
     ULONG BusNumber;
     ULONG SlotNumber;
     ULONG Reserved[3];
     ULONG AlternativeLists;
     IO_RESOURCE_LIST List[1];
} IO_RESOURCE_REQUIREMENTS_LIST, *PIO_RESOURCE_REQUIREMENTS_LIST;

Windows Vista Kernel Structures