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DXGK_PTE structure (d3dukmdt.h)

  • Article

A page table entry (PTE) provides a physical address of a page and other attributes. The exact format of PTE depends on hardware implementation.

Syntax

typedef struct _DXGK_PTE {
  union {
    struct {
      ULONGLONG Valid : 1;
      ULONGLONG Zero : 1;
      ULONGLONG CacheCoherent : 1;
      ULONGLONG ReadOnly : 1;
      ULONGLONG NoExecute : 1;
      ULONGLONG Segment : 5;
      ULONGLONG LargePage : 1;
      ULONGLONG PhysicalAdapterIndex : 6;
      ULONGLONG PageTablePageSize : 2;
      ULONGLONG SystemReserved0 : 1;
      ULONGLONG Reserved : 44;
    };
    ULONGLONG Flags;
  };
  union {
    ULONGLONG PageAddress;
    ULONGLONG PageTableAddress;
  };
} DXGK_PTE;

Members

Valid

When set, this indicates that the entry is valid. Accessing an invalid entry leads to an unrecoverable address fault, unless the Zero flag is set.

Zero

When set with Valid = 1, the access to the entry lead to returning the zero value for the memory access. This is used to support tiled resources.

Supported starting with Windows 10.

CacheCoherent

When set, this indicates that the memory page is cache coherent between CPU and GPU.

ReadOnly

When set, this indicates that the memory page is read only.

NoExecute

When set, this indicates that the memory page contains data, which should not be treated as executable commands.

Supported starting with Windows 10.

Segment

A zero-based GPU memory segment identifier where the corresponding memory page is located. The segment zero is reserved for system memory.

LargePage

The bit can be set only when the kernel mode driver sets the DXGK_VIRTUALADDRESSCAPS::GpuMmu.LargePageSupported cap. When set the page table address (PageTableAddress + SegmentId) is the memory address of an allocation. The allocation size is equal to the virtual address range, covered by the lower page table level. This flag cannot be set for the leaf page tables.

Supported starting with Windows 10.

PhysicalAdapterIndex

Defines a physical adapter index in a linked display adapter configuration. PTEs of page tables on one physical adapter can point to memory on another physical adapter.

Supported starting with Windows 10.

PageTablePageSize

For the level 1 page table entry defines the pages size of the leaf page table PTEs. The value is provided by the DXGK_PTE_PAGE_SIZE enumerator. This value should be ignored when dual-PTE is supported.

Supported starting with Windows 10.

SystemReserved0

Reserved

Reserved for system use and will be set to zero.

Flags

The unmasked value of the structure.

PageAddress

The high 52 bits of the 64 bit physical address of a memory page. The low 12 bits are zero. The address is an offset from the start of the segment, defined by Segment, or a system memory address.

PageTableAddress

The high 52 bits of the 64 bit physical address of a lower level page table. The low 12 bits are zero. The address is an offset from the start of the segment, defined by Segment, or a system memory address.

Supported starting with Windows 10.

Requirements

Requirement Value
Minimum supported client Available in Windows 7 and later versions of the Windows operating systems.
Header d3dukmdt.h (include D3dkmddi.h)