DXGKDDI_GETMMIORANGES callback function (dispmprt.h)

Get the memory ranges for a single MMIO (memory mapped input output) BAR (base address register) in the virtual device.

Syntax

DXGKDDI_GETMMIORANGES DxgkddiGetmmioranges;

NTSTATUS DxgkddiGetmmioranges(
  HANDLE Context,
  PDXGKARG_GETMMIORANGES pArgs
)
{...}

Parameters

Context

A handle to the device context.

pArgs

Pointer to a DXGKARG_GETMMIORANGES structure.

Return value

Returns:

• STATUS_SUCCESS The IHV system did not encounter any errors.
• STATUS_INVALID_DEVICE_REQUEST The virtual device encountered an error and should be forcibly stopped. Failure here will cause virtual device failure.
• BUFFER_TO_SMALL may result in this being called again with a larger buffer.

Remarks

This callback function gets the specific ranges on which intercepts and mapping must be placed. This is a more flexible scatter/gather mapping of the BARs than the general SR-IOV (single-root input/output virtualization) solution that allows for VF (virtual function) BARS (base address registers) to be different sized than the physical bars and map/emulate any order of pages from any physical bar to any virtual bar. This function MUST contain a mapping for every page in the virtual bar. If it does not the device will fail to be created.

Requirements