VDMAD_Get_Region_Info

include vdmad.inc

mov eax, DMA_Handle
VxDcall VDMAD_Get_Region_Info
mov [Buffer], bl
mov [LockFlag], bh
mov Region, esi
mov [RegionSize], ecx
 

Returns data describing the current region assigned to a DMA handle. This data includes the buffer identifier, page status, region address, and buffer size. Uses EBX, ECX, ESI

BL Specifies the buffer identifier.
BH Specifies whether pages are locked (zero is not locked, nonzero is locked).
ESI Specifies the linear region.
ECX Specifies the size of the buffer in bytes.

DMA_Handle
Handle of the DMA.

The data returned by this service can be used by a handler when it calls following services:

VDMAD_Unlock_DMA_Region

VDMAD_Release_Buffer

VDMAD_Copy_To_Buffer

VDMAD_Copy_From_Buffer