VideoPortReleaseCommonBuffer function

The VideoPortReleaseCommonBuffer function frees a common buffer that was previously allocated by VideoPortAllocateCommonBuffer.

Syntax

VIDEOPORT_API VOID VideoPortReleaseCommonBuffer(
  IN PVOID            HwDeviceExtension,
  IN PVP_DMA_ADAPTER  VpDmaAdapter,
  IN ULONG            Length,
  IN PHYSICAL_ADDRESS LogicalAddress,
  IN PVOID            VirtualAddress,
  IN BOOLEAN          CacheEnabled
);

Parameters

HwDeviceExtension

Pointer to the miniport driver's device extension.

VpDmaAdapter

Pointer to the VP_DMA_ADAPTER structure that represents the bus-master adapter. This is the structure returned after a call to VideoPortGetDmaAdapter.

Length

Specifies the number of bytes of memory to be freed.

LogicalAddress

Specifies the logical address of the buffer to be freed.

VirtualAddress

Pointer to the corresponding virtual address of the allocated memory range. This value was obtained in a prior call to VideoPortAllocateCommonBuffer.

CacheEnabled

Indicates whether the allocated memory is cached. A value of TRUE indicates that the allocated memory is cached.

Return Value

None

Remarks

The parameters passed to VideoPortFreeCommonBuffer must match exactly those passed to and returned from VideoPortAllocateCommonBuffer. A driver cannot free only part of an allocated common buffer.

Requirements

   
Minimum supported client Available in Windows XP and later versions of the Windows operating systems.
Target Platform Desktop
Header video.h (include Video.h, Ntdef.h)
Library Videoprt.lib
DLL Videoprt.sys
IRQL PASSIVE_LEVEL

See Also

VP_DMA_ADAPTER

VideoPortAllocateCommonBuffer

VideoPortGetDmaAdapter