PAGP_FREE_PHYSICAL callback function (videoagp.h)

Article
02/22/2024

The AgpFreePhysical function frees system memory that was committed by a previous call to AgpCommitPhysical.

Syntax

PAGP_FREE_PHYSICAL PagpFreePhysical;

void PagpFreePhysical(
  [in] IN PVOID HwDeviceExtension,
  [in] IN PVOID PhysicalReserveContext,
  [in] IN ULONG Pages,
  [in] IN ULONG Offset
)
{...}

Parameters

[in] HwDeviceExtension

Pointer to the device extension of the miniport driver.

[in] PhysicalReserveContext

Identifies a reserved physical address range. This context handle was obtained from AgpReservePhysical.

[in] Pages

Specifies the number of pages of system memory that the video port driver should unmap.

[in] Offset

Specifies the page offset into the reserved physical address range identified by PhysicalReserveContext that indicates the actual base address at which to unmap system memory.

Return value

None

Remarks

When a miniport driver calls AgpFreePhysical, Pages pages of physical memory are unlocked and unmapped from the AGP-decodable physical address range. This range begins Offset pages into the range identified by PhysicalReserveContext. The miniport driver must specify that the exact offset and number of pages be freed as were committed in a prior call to AgpCommitPhysical.

Requirements

Requirement	Value
Minimum supported client	Available in Windows 2000 and later versions of the Windows operating systems.
Target Platform	Desktop
Header	videoagp.h (include Video.h)
IRQL	PASSIVE_LEVEL