struct MMVAD_FLAGS

typedef struct _MMVAD_FLAGS
{
     ULONG CommitCharge: 19;
     ULONG NoChange: 1;
     ULONG VadType: 3;
     ULONG MemCommit: 1;
     ULONG Protection: 5;
     ULONG Spare: 2;
     ULONG PrivateMemory: 1;
} MMVAD_FLAGS, *PMMVAD_FLAGS;

Windows Vista Kernel Structures