typedef struct _HARDWARE_PTE_X86
{
     ULONG Valid: 1;
     ULONG Write: 1;
     ULONG Owner: 1;
     ULONG WriteThrough: 1;
     ULONG CacheDisable: 1;
     ULONG Accessed: 1;
     ULONG Dirty: 1;
     ULONG LargePage: 1;
     ULONG Global: 1;
     ULONG CopyOnWrite: 1;
     ULONG Prototype: 1;
     ULONG reserved: 1;
     ULONG PageFrameNumber: 20;
} HARDWARE_PTE_X86, *PHARDWARE_PTE_X86;

Windows Vista Kernel Structures