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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 x has been deprecated and is superseded by NDIS 6.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

NdisMSetupDmaTransfer

NdisMStartBufferPhysicalMapping

 

 

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