VideoPortUnmapMemory

VP_STATUS VideoPortUnmapMemory(

PVOID HwDeviceExtension,

PVOID VirtualAddress,

HANDLE ProcessHandle

);

VideoPortUnmapMemory releases a mapping between a logical address range for the adapter and a virtual address range in the user-mode address space of a particular thread. This function is the reciprocal of VideoPortMapMemory and VideoPortMapBankedMemory.

Parameters

HwDeviceExtension: Points to the miniport driver’s device extension.
VirtualAddress: Points to a virtual address within the mapped range to be released.
ProcessHandle: Should be set to zero, or to the process handle specified when the miniport called VideoPortMapMemory.

Return Value

VideoPortUnmapMemory returns NO_ERROR if the mapping was released. Otherwise, it returns ERROR_INVALID_PARAMETER.

Comments

A miniport driver cannot release a subrange of the mapping between a logical device range and the user-space virtual address range of its corresponding display driver. Whether the VirtualAddress parameter is the base virtual address for the mapped range that was returned by VideoPortMapMemory or VideoPortMapBankedMemory, or is an offset into that mapped virtual range, VideoPortUnmapMemory releases the mapping for the full range.

PVOID HwDeviceExtension,
PVOID VirtualAddress,
HANDLE ProcessHandle
);