typedef struct _ARBITER_ALLOCATION_STATE
{
     UINT64 Start;
     UINT64 End;
     UINT64 CurrentMinimum;
     UINT64 CurrentMaximum;
     PARBITER_LIST_ENTRY Entry;
     PARBITER_ALTERNATIVE CurrentAlternative;
     ULONG AlternativeCount;
     PARBITER_ALTERNATIVE Alternatives;
     WORD Flags;
     UCHAR RangeAttributes;
     UCHAR RangeAvailableAttributes;
     ULONG WorkSpace;
} ARBITER_ALLOCATION_STATE, *PARBITER_ALLOCATION_STATE;

Windows Vista Kernel Structures