VideoPortReleaseCommonBuffer function

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

Syntax


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 [in]

Pointer to the miniport driver's device extension.

VpDmaAdapter [in]

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

Length [in]

Specifies the number of bytes of memory to be freed.

LogicalAddress [in]

Specifies the logical address of the buffer to be freed.

VirtualAddress [in]

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

CacheEnabled [in]

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

Target platform

Version

Available in Windows XP and later versions of the Windows operating systems.

Header

Video.h (include Video.h or Ntdef.h)

Library

Videoprt.lib

DLL

Videoprt.sys

IRQL

PASSIVE_LEVEL

See also

VideoPortAllocateCommonBuffer
VideoPortGetDmaAdapter
VP_DMA_ADAPTER

 

 

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