protocol.c

NDIS Intermediate Driver

NDIS_STATUS
PtReceive(
    IN  NDIS_HANDLE         ProtocolBindingContext,
    IN  NDIS_HANDLE         MacReceiveContext,
    IN  PVOID               HeaderBuffer,
    IN  UINT                HeaderBufferSize,
    IN  PVOID               LookAheadBuffer,
    IN  UINT                LookAheadBufferSize,
    IN  UINT                PacketSize
    )
/*++

Routine Description:

    Handle receive data indicated up by the miniport below. We pass
    it along to the protocol above us.

    If the miniport below indicates packets, NDIS would more
    likely call us at our ReceivePacket handler. However we
    might be called here in certain situations even though
    the miniport below has indicated a receive packet, e.g.
    if the miniport had set packet status to NDIS_STATUS_RESOURCES.
        
Arguments:

    <see DDK ref page for ProtocolReceive>

Return Value:

    NDIS_STATUS_SUCCESS if we processed the receive successfully,
    NDIS_STATUS_XXX error code if we discarded it.

--*/
{
    PADAPT            pAdapt = (PADAPT)ProtocolBindingContext;
    PNDIS_PACKET      MyPacket, Packet = NULL;
    NDIS_STATUS       Status = NDIS_STATUS_SUCCESS;

    if ((!pAdapt->MiniportHandle) || (pAdapt->MPDeviceState > NdisDeviceStateD0))
    {
        Status = NDIS_STATUS_FAILURE;
    }
    else do
    {
        //
        // Get at the packet, if any, indicated up by the miniport below.
        //
        Packet = NdisGetReceivedPacket(pAdapt->BindingHandle, MacReceiveContext);
        if (Packet != NULL)
        {
            //
            // The miniport below did indicate up a packet. Use information
            // from that packet to construct a new packet to indicate up.
            //

#ifdef NDIS51
            //
            // NDIS 5.1 NOTE: Do not reuse the original packet in indicating
            // up a receive, even if there is sufficient packet stack space.
            // If we had to do so, we would have had to overwrite the
            // status field in the original packet to NDIS_STATUS_RESOURCES,
            // and it is not allowed for protocols to overwrite this field
            // in received packets.
            //
#endif // NDIS51

            //
            // Get a packet off the pool and indicate that up
            //
            NdisDprAllocatePacket(&Status,
                                &MyPacket,
                                pAdapt->RecvPacketPoolHandle);

            if (Status == NDIS_STATUS_SUCCESS)
            {
                //
                // Make our packet point to data from the original
                // packet. NOTE: this works only because we are
                // indicating a receive directly from the context of
                // our receive indication. If we need to queue this
                // packet and indicate it from another thread context,
                // we will also have to allocate a new buffer and copy
                // over the packet contents, OOB data and per-packet
                // information. This is because the packet data
                // is available only for the duration of this
                // receive indication call.
                //
                NDIS_PACKET_FIRST_NDIS_BUFFER(MyPacket) = NDIS_PACKET_FIRST_NDIS_BUFFER(Packet);
                NDIS_PACKET_LAST_NDIS_BUFFER(MyPacket) = NDIS_PACKET_LAST_NDIS_BUFFER(Packet);

                //
                // Get the original packet (it could be the same packet as the
                // one received or a different one based on the number of layered
                // miniports below) and set it on the indicated packet so the OOB
                // data is visible correctly at protocols above.
                //
                NDIS_SET_ORIGINAL_PACKET(MyPacket, NDIS_GET_ORIGINAL_PACKET(Packet));
                NDIS_SET_PACKET_HEADER_SIZE(MyPacket, HeaderBufferSize);

                //
                // Copy packet flags.
                //
                NdisGetPacketFlags(MyPacket) = NdisGetPacketFlags(Packet);

                //
                // Force protocols above to make a copy if they want to hang
                // on to data in this packet. This is because we are in our
                // Receive handler (not ReceivePacket) and we can't return a
                // ref count from here.
                //
                NDIS_SET_PACKET_STATUS(MyPacket, NDIS_STATUS_RESOURCES);

                //
                // By setting NDIS_STATUS_RESOURCES, we also know that we can reclaim
                // this packet as soon as the call to NdisMIndicateReceivePacket
                // returns.
                //
                // NOTE: we queue the packet and indicate this packet immediately with
                // the already queued packets together. We have to the queue the packet 
                // first because some versions of NDIS might call protocols' 
                // ReceiveHandler(not ReceivePacketHandler) if the packet indicate status 
                // is NDIS_STATUS_RESOURCES. If the miniport below indicates an array of 
                // packets, some of them with status NDIS_STATUS_SUCCESS, some of them 
                // with status NDIS_STATUS_RESOURCES, PtReceive might be called, by 
                // doing this way, we preserve the receive order of packets.
                // 
                PtQueueReceivedPacket(pAdapt, MyPacket, TRUE);
                //
                // Reclaim the indicated packet. Since we had set its status
                // to NDIS_STATUS_RESOURCES, we are guaranteed that protocols
                // above are done with it.
                //
                NdisDprFreePacket(MyPacket);

                break;
            }
        }
        else
        {
            //
            // The miniport below us uses the old-style (not packet)
            // receive indication. Fall through.
            //
        }

        //
        // Fall through if the miniport below us has either not
        // indicated a packet or we could not allocate one
        //
        if (Packet != NULL)
        {
            //
            // We are here because we failed to allocate packet
            //
            PtFlushReceiveQueue(pAdapt);
        }
        //
        // Here the driver checks if the miniport adapter is in lower power state, do not indicate the 
        // packets, but the check does not close the window, it only minimizes the window. To close
        // the window completely, we need to add synchronization in the receive code path; because 
        // NDIS can handle the case that miniport drivers indicate packets in lower power state,
        // we don't add the synchronization in the hot code path.
        //    
        if ((pAdapt->MiniportHandle == NULL)
                || (pAdapt->MPDeviceState > NdisDeviceStateD0))
        {
            break;
        }
        
        pAdapt->IndicateRcvComplete = TRUE;
        switch (pAdapt->Medium)
        {
            case NdisMedium802_3:
            case NdisMediumWan:
                NdisMEthIndicateReceive(pAdapt->MiniportHandle,
                                             MacReceiveContext,
                                             HeaderBuffer,
                                             HeaderBufferSize,
                                             LookAheadBuffer,
                                             LookAheadBufferSize,
                                             PacketSize);
                break;

            case NdisMedium802_5:
                NdisMTrIndicateReceive(pAdapt->MiniportHandle,
                                            MacReceiveContext,
                                            HeaderBuffer,
                                            HeaderBufferSize,
                                            LookAheadBuffer,
                                            LookAheadBufferSize,
                                            PacketSize);
                break;

            case NdisMediumFddi:
                NdisMFddiIndicateReceive(pAdapt->MiniportHandle,
                                              MacReceiveContext,
                                              HeaderBuffer,
                                              HeaderBufferSize,
                                              LookAheadBuffer,
                                              LookAheadBufferSize,
                                              PacketSize);
                break;

            default:
                ASSERT(FALSE);
                break;
        }

    } while(FALSE);

    return Status;
}


VOID
PtReceiveComplete(
    IN NDIS_HANDLE        ProtocolBindingContext
    )
/*++

Routine Description:

    Called by the adapter below us when it is done indicating a batch of
    received packets.

Arguments:

    ProtocolBindingContext    Pointer to our adapter structure.

Return Value:

    None

--*/
{
    PADAPT        pAdapt =(PADAPT)ProtocolBindingContext;
    PNDIS_PACKET  PacketArray[MAX_RECEIVE_PACKET_ARRAY_SIZE];
    ULONG         NumberOfPackets = 0, i;

    PtFlushReceiveQueue(pAdapt);
        
    if ((pAdapt->MiniportHandle != NULL)
                && (pAdapt->MPDeviceState == NdisDeviceStateD0)
                && (pAdapt->IndicateRcvComplete == TRUE))
    {
        switch (pAdapt->Medium)
        {
            case NdisMedium802_3:
            case NdisMediumWan:
                NdisMEthIndicateReceiveComplete(pAdapt->MiniportHandle);
                break;

            case NdisMedium802_5:
                NdisMTrIndicateReceiveComplete(pAdapt->MiniportHandle);
                break;

            case NdisMediumFddi:
                NdisMFddiIndicateReceiveComplete(pAdapt->MiniportHandle);
                break;

            default:
                ASSERT(FALSE);
                break;
        }
    }

    pAdapt->IndicateRcvComplete = FALSE;
}


INT
PtReceivePacket(
    IN NDIS_HANDLE            ProtocolBindingContext,
    IN PNDIS_PACKET           Packet
    )
/*++

Routine Description:

    ReceivePacket handler. Called by NDIS if the miniport below supports
    NDIS 4.0 style receives. Re-package the buffer chain in a new packet
    and indicate the new packet to protocols above us. Any context for
    packets indicated up must be kept in the MiniportReserved field.

    NDIS 5.1 - packet stacking - if there is sufficient "stack space" in
    the packet passed to us, we can use the same packet in a receive
    indication.

Arguments:

    ProtocolBindingContext - Pointer to our adapter structure.
    Packet - Pointer to the packet

Return Value:

    == 0 -> We are done with the packet
    != 0 -> We will keep the packet and call NdisReturnPackets() this
            many times when done.
--*/
{
    PADAPT              pAdapt =(PADAPT)ProtocolBindingContext;
    NDIS_STATUS         Status;
    PNDIS_PACKET        MyPacket;
    BOOLEAN             Remaining;

    //
    // Drop the packet silently if the upper miniport edge isn't initialized or
    // the miniport edge is in low power state
    //
    if ((!pAdapt->MiniportHandle) || (pAdapt->MPDeviceState > NdisDeviceStateD0))
    {
          return 0;
    }

#ifdef NDIS51
    //
    // Check if we can reuse the same packet for indicating up.
    // See also: PtReceive(). 
    //
    (VOID)NdisIMGetCurrentPacketStack(Packet, &Remaining);
    if (Remaining)
    {
        //
        // We can reuse "Packet". Indicate it up and be done with it.
        //
        Status = NDIS_GET_PACKET_STATUS(Packet);
        if (Status == NDIS_STATUS_RESOURCES)
        {
            PtQueueReceivedPacket(pAdapt, Packet, TRUE);
        }
        else
        {   
             PtQueueReceivedPacket(pAdapt, Packet, FALSE);
        }
        return((Status != NDIS_STATUS_RESOURCES) ? 1 : 0);
    }
#endif // NDIS51

    //
    // Get a packet off the pool and indicate that up
    //
    NdisDprAllocatePacket(&Status,
                           &MyPacket,
                           pAdapt->RecvPacketPoolHandle);

    if (Status == NDIS_STATUS_SUCCESS)
    {
        PRECV_RSVD            RecvRsvd;

        RecvRsvd = (PRECV_RSVD)(MyPacket->MiniportReserved);
        RecvRsvd->OriginalPkt = Packet;

        NDIS_PACKET_FIRST_NDIS_BUFFER(MyPacket) = NDIS_PACKET_FIRST_NDIS_BUFFER(Packet);
        NDIS_PACKET_LAST_NDIS_BUFFER(MyPacket) = NDIS_PACKET_LAST_NDIS_BUFFER(Packet);

        //
        // Get the original packet (it could be the same packet as the one
        // received or a different one based on the number of layered miniports
        // below) and set it on the indicated packet so the OOB data is visible
        // correctly to protocols above us.
        //
        NDIS_SET_ORIGINAL_PACKET(MyPacket, NDIS_GET_ORIGINAL_PACKET(Packet));

        //
        // Set Packet Flags
        //
        NdisGetPacketFlags(MyPacket) = NdisGetPacketFlags(Packet);

        Status = NDIS_GET_PACKET_STATUS(Packet);

        NDIS_SET_PACKET_STATUS(MyPacket, Status);
        NDIS_SET_PACKET_HEADER_SIZE(MyPacket, NDIS_GET_PACKET_HEADER_SIZE(Packet));

        if (Status == NDIS_STATUS_RESOURCES)
        {
            PtQueueReceivedPacket(pAdapt, MyPacket, TRUE);
        }
        else
        {
            PtQueueReceivedPacket(pAdapt, MyPacket, FALSE);
        }

        //
        // Check if we had indicated up the packet with NDIS_STATUS_RESOURCES
        // NOTE -- do not use NDIS_GET_PACKET_STATUS(MyPacket) for this since
        // it might have changed! Use the value saved in the local variable.
        //
        if (Status == NDIS_STATUS_RESOURCES)
        {
            //
            // Our ReturnPackets handler will not be called for this packet.
            // We should reclaim it right here.
            //
            NdisDprFreePacket(MyPacket);
        }

        return((Status != NDIS_STATUS_RESOURCES) ? 1 : 0);
    }
    else
    {
        //
        // We are out of packets. Silently drop it.
        //
        return(0);
    }
}




NDIS_STATUS
PtPNPHandler(
    IN NDIS_HANDLE        ProtocolBindingContext,
    IN PNET_PNP_EVENT     pNetPnPEvent
    )

/*++
Routine Description:

    This is called by NDIS to notify us of a PNP event related to a lower
    binding. Based on the event, this dispatches to other helper routines.

    NDIS 5.1: forward this event to the upper protocol(s) by calling
    NdisIMNotifyPnPEvent.

Arguments:

    ProtocolBindingContext - Pointer to our adapter structure. Can be NULL
                for "global" notifications

    pNetPnPEvent - Pointer to the PNP event to be processed.

Return Value:

    NDIS_STATUS code indicating status of event processing.

--*/
{