Specifying Segments When Creating Allocations
The display miniport driver specifies and returns information about its memory segments that it prefers the video memory manager use when the video memory manager calls the driver's DxgkDdiCreateAllocation function. In the call to DxgkDdiCreateAllocation, the driver creates allocations for video resources. The driver returns identifiers of supported segments and segment preferences in the DXGK_ALLOCATIONINFO structures that describe the allocations.
From the returned segment information, the video memory manager determines the appropriate memory segment to page-in for the given operation.