recv.c

网络驱动开发

/*++

Copyright (c) 2000  Microsoft Corporation

Module Name:

    recv.c

Abstract:

    NDIS protocol entry points and utility routines to handle receiving
    data.

Environment:

    Kernel mode only.

Revision History:

    arvindm     4/6/2000    Created

--*/

#include "precomp.h"

#define __FILENUMBER 'VCER'



NTSTATUS
NdisProtRead(
    IN PDEVICE_OBJECT       pDeviceObject,
    IN PIRP                 pIrp
    )
/*++

Routine Description:

    Dispatch routine to handle IRP_MJ_READ. 

Arguments:

    pDeviceObject - pointer to our device object
    pIrp - Pointer to request packet

Return Value:

    NT status code.

--*/
{
    PIO_STACK_LOCATION      pIrpSp;
    NTSTATUS                NtStatus;
    PNDISPROT_OPEN_CONTEXT   pOpenContext;

    UNREFERENCED_PARAMETER(pDeviceObject);
    
    pIrpSp = IoGetCurrentIrpStackLocation(pIrp);
    pOpenContext = pIrpSp->FileObject->FsContext;

    do
    {
        //
        // Validate!
        //
        if (pOpenContext == NULL)
        {
            DEBUGP(DL_FATAL, ("Read: NULL FsContext on FileObject %p\n",
                        pIrpSp->FileObject));
            NtStatus = STATUS_INVALID_HANDLE;
            break;
        }
            
        NPROT_STRUCT_ASSERT(pOpenContext, oc);

        if (pIrp->MdlAddress == NULL)
        {
            DEBUGP(DL_FATAL, ("Read: NULL MDL address on IRP %p\n", pIrp));
            NtStatus = STATUS_INVALID_PARAMETER;
            break;
        }

        //
        // Try to get a virtual address for the MDL.
        //
#ifndef WIN9X
        if (MmGetSystemAddressForMdlSafe(pIrp->MdlAddress, NormalPagePriority) == NULL)
        {
            DEBUGP(DL_FATAL, ("Read: MmGetSystemAddr failed for IRP %p, MDL %p\n",
                    pIrp, pIrp->MdlAddress));
            NtStatus = STATUS_INSUFFICIENT_RESOURCES;
            break;
        }
#endif
        NPROT_ACQUIRE_LOCK(&pOpenContext->Lock);

        if (!NPROT_TEST_FLAGS(pOpenContext->Flags, NUIOO_BIND_FLAGS, NUIOO_BIND_ACTIVE))
        {
            NPROT_RELEASE_LOCK(&pOpenContext->Lock);
            NtStatus = STATUS_INVALID_HANDLE;
            break;
        }

        //
        //  Add this IRP to the list of pended Read IRPs
        //
        NPROT_INSERT_TAIL_LIST(&pOpenContext->PendedReads, &pIrp->Tail.Overlay.ListEntry);
        NPROT_REF_OPEN(pOpenContext);  // pended read IRP
        pOpenContext->PendedReadCount++;

        //
        //  Set up the IRP for possible cancellation.
        //
        pIrp->Tail.Overlay.DriverContext[0] = (PVOID)pOpenContext;
        IoMarkIrpPending(pIrp);
        IoSetCancelRoutine(pIrp, NdisProtCancelRead);

        NPROT_RELEASE_LOCK(&pOpenContext->Lock);

        NtStatus = STATUS_PENDING;

        //
        //  Run the service routine for reads.
        //
        ndisprotServiceReads(pOpenContext);

    }
    while (FALSE);

    if (NtStatus != STATUS_PENDING)
    {
        NPROT_ASSERT(NtStatus != STATUS_SUCCESS);
        pIrp->IoStatus.Information = 0;
        pIrp->IoStatus.Status = NtStatus;
        IoCompleteRequest(pIrp, IO_NO_INCREMENT);
    }

    return (NtStatus);
}


VOID
NdisProtCancelRead(
    IN PDEVICE_OBJECT               pDeviceObject,
    IN PIRP                         pIrp
    )
/*++

Routine Description:

    Cancel a pending read IRP. We unlink the IRP from the open context
    queue and complete it.

Arguments:

    pDeviceObject - pointer to our device object
    pIrp - IRP to be cancelled

Return Value:

    None

--*/
{
    PNDISPROT_OPEN_CONTEXT       pOpenContext;
    PLIST_ENTRY                 pIrpEntry;
    BOOLEAN                     Found;

    UNREFERENCED_PARAMETER(pDeviceObject);
    
    IoReleaseCancelSpinLock(pIrp->CancelIrql);

    Found = FALSE;

    pOpenContext = (PNDISPROT_OPEN_CONTEXT) pIrp->Tail.Overlay.DriverContext[0];
    NPROT_STRUCT_ASSERT(pOpenContext, oc);

    NPROT_ACQUIRE_LOCK(&pOpenContext->Lock);

    //
    //  Locate the IRP in the pended read queue and remove it if found.
    //
    for (pIrpEntry = pOpenContext->PendedReads.Flink;
         pIrpEntry != &pOpenContext->PendedReads;
         pIrpEntry = pIrpEntry->Flink)
    {
        if (pIrp == CONTAINING_RECORD(pIrpEntry, IRP, Tail.Overlay.ListEntry))
        {
            NPROT_REMOVE_ENTRY_LIST(&pIrp->Tail.Overlay.ListEntry);
            pOpenContext->PendedReadCount--;
            Found = TRUE;
            break;
        }
    }

    NPROT_RELEASE_LOCK(&pOpenContext->Lock);

    if (Found)
    {
        DEBUGP(DL_INFO, ("CancelRead: Open %p, IRP %p\n", pOpenContext, pIrp));
        pIrp->IoStatus.Status = STATUS_CANCELLED;
        pIrp->IoStatus.Information = 0;
        IoCompleteRequest(pIrp, IO_NO_INCREMENT);

        NPROT_DEREF_OPEN(pOpenContext); // Cancel removed pended Read
    }
}
        


VOID
ndisprotServiceReads(
    IN PNDISPROT_OPEN_CONTEXT        pOpenContext
    )
/*++

Routine Description:

    Utility routine to copy received data into user buffers and
    complete READ IRPs.

Arguments:

    pOpenContext - pointer to open context

Return Value:

    None

--*/
{
    PIRP                pIrp;
    PLIST_ENTRY         pIrpEntry;
    PNDIS_PACKET        pRcvPacket;
    PLIST_ENTRY         pRcvPacketEntry;
    PUCHAR              pSrc, pDst;
    ULONG               BytesRemaining; // at pDst
    PNDIS_BUFFER        pNdisBuffer;
    ULONG               BytesAvailable;
    BOOLEAN             FoundPendingIrp;

    DEBUGP(DL_VERY_LOUD, ("ServiceReads: open %p/%x\n",
            pOpenContext, pOpenContext->Flags));

    NPROT_REF_OPEN(pOpenContext);  // temp ref - service reads

    NPROT_ACQUIRE_LOCK(&pOpenContext->Lock);

    while (!NPROT_IS_LIST_EMPTY(&pOpenContext->PendedReads) &&
           !NPROT_IS_LIST_EMPTY(&pOpenContext->RecvPktQueue))
    {
        FoundPendingIrp = FALSE;
        //
        //  Get the first pended Read IRP
        //
        pIrpEntry = pOpenContext->PendedReads.Flink;
        while (pIrpEntry != &pOpenContext->PendedReads)
        {
            pIrp = CONTAINING_RECORD(pIrpEntry, IRP, Tail.Overlay.ListEntry);

            //
            //  Check to see if it is being cancelled.
            //
            if (IoSetCancelRoutine(pIrp, NULL))
            {
                //
                //  It isn't being cancelled, and can't be cancelled henceforth.
                //
                NPROT_REMOVE_ENTRY_LIST(pIrpEntry);
                FoundPendingIrp = TRUE;
                break;

                //
                //  NOTE: we decrement PendedReadCount way below in the
                //  while loop, to avoid letting through a thread trying
                //  to unbind.
                //
            }
            else
            {
                //
                //  The IRP is being cancelled; let the cancel routine handle it.
                //
                DEBUGP(DL_INFO, ("ServiceReads: open %p, skipping cancelled IRP %p\n",
                        pOpenContext, pIrp));
                pIrpEntry = pIrpEntry->Flink;

            }
        }
        //
        // If no pending IRP
        //
        if (FoundPendingIrp == FALSE)
        {
            break;
        }
        //
        //  Get the first queued receive packet
        //
        pRcvPacketEntry = pOpenContext->RecvPktQueue.Flink;
        NPROT_REMOVE_ENTRY_LIST(pRcvPacketEntry);

        pOpenContext->RecvPktCount --;

        NPROT_RELEASE_LOCK(&pOpenContext->Lock);

        NPROT_DEREF_OPEN(pOpenContext);  // Service: dequeue rcv packet

        pRcvPacket = NPROT_LIST_ENTRY_TO_RCV_PKT(pRcvPacketEntry);

        //
        //  Copy as much data as possible from the receive packet to
        //  the IRP MDL.
        //
#ifndef WIN9X
        pDst = MmGetSystemAddressForMdlSafe(pIrp->MdlAddress, NormalPagePriority);
        NPROT_ASSERT(pDst != NULL);  // since it was already mapped
#else
        pDst = MmGetSystemAddressForMdl(pIrp->MdlAddress);  // Win9x
#endif
        BytesRemaining = MmGetMdlByteCount(pIrp->MdlAddress);

        pNdisBuffer = NDIS_PACKET_FIRST_NDIS_BUFFER(pRcvPacket);

        //
        // Copy the data in the received packet into the buffer provided by the client.
        // If the length of the receive packet is greater than length of the given buffer, 
        // we just copy as many bytes as we can. Once the buffer is full, we just discard 
        // the rest of the data, and complete the IRP sucessfully even we only did a partial copy.
        // 
        while (BytesRemaining && (pNdisBuffer != NULL))
        {
#ifndef WIN9X
            NdisQueryBufferSafe(pNdisBuffer, &pSrc, &BytesAvailable, NormalPagePriority);

            if (pSrc == NULL) 
            {
                DEBUGP(DL_FATAL,
                    ("ServiceReads: Open %p, QueryBuffer failed for buffer %p\n",
                            pOpenContext, pNdisBuffer));
                break;
            }
#else
            NdisQueryBuffer(pNdisBuffer, &pSrc, &BytesAvailable);
#endif

            if (BytesAvailable)
            {
                ULONG       BytesToCopy = MIN(BytesAvailable, BytesRemaining);

                NPROT_COPY_MEM(pDst, pSrc, BytesToCopy);
                BytesRemaining -= BytesToCopy;
                pDst += BytesToCopy;
            }

            NdisGetNextBuffer(pNdisBuffer, &pNdisBuffer);
        }

        //
        //  Complete the IRP.
        //
        pIrp->IoStatus.Status = STATUS_SUCCESS;
        pIrp->IoStatus.Information = MmGetMdlByteCount(pIrp->MdlAddress) - BytesRemaining;

        DEBUGP(DL_INFO, ("ServiceReads: Open %p, IRP %p completed with %d bytes\n",
            pOpenContext, pIrp, pIrp->IoStatus.Information));

        IoCompleteRequest(pIrp, IO_NO_INCREMENT);

        //
        //  Free up the receive packet - back to the miniport if it
        //  belongs to it, else reclaim it (local copy).
        //
        if (NdisGetPoolFromPacket(pRcvPacket) != pOpenContext->RecvPacketPool)
        {
            NdisReturnPackets(&pRcvPacket, 1);
        }
        else
        {
            ndisprotFreeReceivePacket(pOpenContext, pRcvPacket);
        }

        NPROT_DEREF_OPEN(pOpenContext);    // took out pended Read

        NPROT_ACQUIRE_LOCK(&pOpenContext->Lock);
        pOpenContext->PendedReadCount--;

    }

    NPROT_RELEASE_LOCK(&pOpenContext->Lock);

    NPROT_DEREF_OPEN(pOpenContext);    // temp ref - service reads
}




NDIS_STATUS
NdisProtReceive(
    IN NDIS_HANDLE                  ProtocolBindingContext,
    IN NDIS_HANDLE                  MacReceiveContext,
    IN PVOID                        pHeaderBuffer,
    IN UINT                         HeaderBufferSize,
    IN PVOID                        pLookaheadBuffer,
    IN UINT                         LookaheadBufferSize,
    IN UINT                         PacketSize
    )
/*++