NDIS_BUFFER_TO_SPAN_PAGES function
Note NDIS 5. x has been deprecated and is superseded by NDIS 6. x. For new NDIS driver development, see Network Drivers Starting with Windows Vista. For information about porting NDIS 5. x drivers to NDIS 6. x, see Porting NDIS 5.x Drivers to NDIS 6.0.
NDIS_BUFFER_TO_SPAN_PAGES determines how many physical pages of memory are being used to back a given buffer.
Syntax
ULONG NDIS_BUFFER_TO_SPAN_PAGES(
_In_ PNDIS_BUFFER Buffer
);
Parameters
- Buffer [in]
Specifies the buffer descriptor mapping the buffer.
Return value
NDIS_BUFFER_TO_SPAN_PAGES returns the number of pages backing the virtual range for the buffer.
Remarks
This macro can be used by DMA drivers to determine how many physical discontiguities exist in a given virtual buffer.
Requirements
Target platform |
Universal |
Version |
Not supported for NDIS 6.0 drivers in Windows Vista. Use NDIS_MDL_TO_SPAN_PAGESinstead. Supported in NDIS 5.1 drivers in lh1 and Windows XP. |
Header |
Ndis.h (include Ndis.h) |
Library |
Ndis.lib |
IRQL |
Any level |
See also
NdisMStartBufferPhysicalMapping