NdisReinitializePacket

NdisReinitializePacket

VOID
   NdisReinitializePacket(
       IN OUT PNDIS_PACKET Packet
       );

NdisReinitializePacket removes any chained buffers from a given packet and reinitializes it for reuse.

Parameters

Packet

Points to the packet descriptor, allocated by the caller.

Comments

NdisReinitializePacket reinitialize a packet descriptor so the MiniportReserved and ProtocolReserved arrays contain all zeros and the head of the buffer chain is set to NULL.

A driver can call NdisReinitializePacket only with packet descriptors allocated by that driver. For example, a MiniportReturnPacket function is likely to call NdisReinitializePacket to prepare a driver-allocated packet for use in a subsequent receive indication.

Before calling NdisReinitializePacket, a driver must call NdisFreeBuffer or NdisUnchainBufferAtXxx as many times as necessary to release or to save all buffer descriptors chained to the packet. Otherwise, a call to NdisReinitializePacket causes a memory leak: all memory associated with the buffer descriptor chain cannot be used by NDIS nor by the driver until the system is rebooted.

A driver can call NdisQueryPacket to determine how many buffer descriptors are chained to a given packet and, therefore, how many calls to NdisFreeBuffer or NdisUnchainBufferAtXxx are required. It can call NdisGetNextBuffer to retrieve each buffer descriptor pointer to pass to NdisFreeBuffer.

A call to NdisReinitializePacket has no effect on the NDIS_PACKET_OOB_DATA block associated with the packet descriptor. To prepare this block for reuse, the allocating driver can either call NdisZeroMemory with the pointer returned by NDIS_OOB_DATA_FROM_PACKET or it can reset the relevant members with the appropriate NDIS_SET_PACKET_XXX macro(s).

Callers of NdisReinitializePacket can run at any IRQL.