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. |
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