DXGK_QUERYSEGMENTOUT structure (d3dkmddi.h)

The DXGK_QUERYSEGMENTOUT structure describes memory-segment information that the display miniport driver should return from a call to its DxgkDdiQueryAdapterInfo function.

Syntax

typedef struct _DXGK_QUERYSEGMENTOUT {
  [out] UINT                   NbSegment;
  [out] DXGK_SEGMENTDESCRIPTOR *pSegmentDescriptor;
  [out] UINT                   PagingBufferSegmentId;
  [out] UINT                   PagingBufferSize;
  [out] UINT                   PagingBufferPrivateDataSize;
} DXGK_QUERYSEGMENTOUT;

Members

[out] NbSegment

The number of memory segments that the driver supports.

[out] pSegmentDescriptor

An array of DXGK_SEGMENTDESCRIPTOR structures that the driver populates with information about the segments it supports. The size of the array is the value that NbSegment specifies.

[out] PagingBufferSegmentId

The identifier of the segment that the video memory manager should allocate the paging buffer from. This segment must be an aperture segment.

[out] PagingBufferSize

The size, in bytes, that the video memory manager should allocate for the paging buffer.

[out] PagingBufferPrivateDataSize

The size, in bytes, of the driver-resident private data structure that is associated with each paging buffer. Memory for this private data structure is allocated from nonpaged pool. If the driver specifies zero for PagingBufferPrivateDataSize, no memory is allocated for the private data structure.

The private data structure that is associated with a paging buffer is initialized to zero when the paging buffer is created. During the lifetime of the paging buffer, the video memory manager never accesses the private data structure that is associated with the paging buffer.

Remarks

The video memory manager allocates a paging buffer either from an aperture segment (if the PagingBufferSegmentId member identifies the segment) or as a contiguous write-combined memory block (if PagingBufferSegmentId is set to 0). If PagingBufferSegmentId is set to 0, the graphics processing unit (GPU) must access direct memory access (DMA) buffers by using PCI cycles on systems where AGP transfers that occur outside the AGP aperture are not permitted.

Requirements

See also

DXGKARG_QUERYADAPTERINFO

DXGK_QUERYSEGMENTIN

DXGK_SEGMENTDESCRIPTOR

DxgkDdiQueryAdapterInfo