skrlmt.c

linux嵌入式课程实践中的一个关于声卡驱动程序 。

		pSPacket->PortId[0] = SK_RLMT_SPT_PORT_ID0;
		pSPacket->PortId[1] = SK_RLMT_SPT_PORT_ID1;
		pSPacket->MessageAge[0] = SK_RLMT_SPT_MSG_AGE0;
		pSPacket->MessageAge[1] = SK_RLMT_SPT_MSG_AGE1;
		pSPacket->MaxAge[0] = SK_RLMT_SPT_MAX_AGE0;
		pSPacket->MaxAge[1] = SK_RLMT_SPT_MAX_AGE1;
		pSPacket->HelloTime[0] = SK_RLMT_SPT_HELLO_TIME0;
		pSPacket->HelloTime[1] = SK_RLMT_SPT_HELLO_TIME1;
		pSPacket->ForwardDelay[0] = SK_RLMT_SPT_FWD_DELAY0;
		pSPacket->ForwardDelay[1] = SK_RLMT_SPT_FWD_DELAY1;

		Length = SK_RLMT_MAX_PACKET_SIZE;	/* Or smaller. */
		pMb->Length = Length;
		pMb->PortIdx = PortNumber;
		Length -= 14;
		SK_U16_TO_NETWORK_ORDER(Length, &pSPacket->TypeLen[0]);

		pAC->Rlmt.Port[PortNumber].TxSpHelloReqCts++;
	}

	return (pMb);       
}	/* SkRlmtBuildSpanningTreePacket */


/******************************************************************************
 *
 *	SkRlmtSend - build and send check packets
 *
 * Description:
 *	Depending on the RLMT state and the checking state, several packets
 *	are sent through the indicated port.
 *
 * Context:
 *	runtime, pageable?
 *
 * Returns:
 *	Nothing.
 */
RLMT_STATIC void	SkRlmtSend(
SK_AC	*pAC,		/* Adapter Context */
SK_IOC	IoC,		/* I/O Context */
SK_U32	PortNumber)	/* Sending port */
{
	unsigned	j;
	SK_EVPARA	Para;
	SK_RLMT_PORT	*pRPort;

	pRPort = &pAC->Rlmt.Port[PortNumber];
	if (pAC->Rlmt.Port[PortNumber].Net->RlmtMode & SK_RLMT_CHECK_LOC_LINK) {
		if (pRPort->CheckingState & (SK_RLMT_PCS_TX | SK_RLMT_PCS_RX)) {
			/* Port is suspicious. Send the RLMT packet to the RLMT mc addr. */
			if ((Para.pParaPtr = SkRlmtBuildPacket(pAC, IoC, PortNumber,
				SK_PACKET_ALIVE, &pAC->Addr.Port[PortNumber].CurrentMacAddress,
				&SkRlmtMcAddr)) != NULL) {
				SkEventQueue(pAC, SKGE_DRV, SK_DRV_RLMT_SEND, Para);
			}
		}
		else {
			/*
			 * Send a directed RLMT packet to all ports that are
			 * checked by the indicated port.
			 */
			for (j = 0; j < pRPort->PortsChecked; j++) {
				if ((Para.pParaPtr = SkRlmtBuildPacket(pAC, IoC, PortNumber,
					SK_PACKET_ALIVE, &pAC->Addr.Port[PortNumber].CurrentMacAddress,
					&pRPort->PortCheck[j].CheckAddr)) != NULL) {
					SkEventQueue(pAC, SKGE_DRV, SK_DRV_RLMT_SEND, Para);
				}
			}
		}
	}

	if ((pAC->Rlmt.Port[PortNumber].Net->RlmtMode & SK_RLMT_CHECK_SEG) &&
		(pAC->Rlmt.Port[PortNumber].Net->CheckingState & SK_RLMT_RCS_SEND_SEG)) {
		/*
		 * Send a BPDU packet to make a connected switch tell us
		 * the correct root bridge.
		 */
		if ((Para.pParaPtr =
			SkRlmtBuildSpanningTreePacket(pAC, IoC, PortNumber)) != NULL) {
			pAC->Rlmt.Port[PortNumber].Net->CheckingState &= ~SK_RLMT_RCS_SEND_SEG;
			pRPort->RootIdSet = SK_FALSE;

			SkEventQueue(pAC, SKGE_DRV, SK_DRV_RLMT_SEND, Para);
			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_TX,
				("SkRlmtSend: BPDU Packet on Port %u.\n", PortNumber))
		}
	}   
	return;   
}	/* SkRlmtSend */


/******************************************************************************
 *
 *	SkRlmtPortReceives - check if port is (going) down and bring it up
 *
 * Description:
 *	This routine checks if a port who received a non-BPDU packet
 *	needs to go up or needs to be stopped going down.
 *
 * Context:
 *	runtime, pageable?
 *
 * Returns:
 *	Nothing.
 */
RLMT_STATIC void	SkRlmtPortReceives(
SK_AC	*pAC,			/* Adapter Context */
SK_IOC	IoC,			/* I/O Context */
SK_U32	PortNumber)		/* Port to check */
{
	SK_RLMT_PORT	*pRPort;
	SK_EVPARA		Para;

	pRPort = &pAC->Rlmt.Port[PortNumber];
	pRPort->PortNoRx = SK_FALSE;

	if ((pRPort->PortState == SK_RLMT_PS_DOWN) &&
		!(pRPort->CheckingState & SK_RLMT_PCS_TX)) {
		/*
		 * Port is marked down (rx), but received a non-BPDU packet.
		 * Bring it up.
		 */
		SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
			("SkRlmtPacketReceive: Received on PortDown.\n"))

		pRPort->PortState = SK_RLMT_PS_GOING_UP;
		pRPort->GuTimeStamp = SkOsGetTime(pAC);
		Para.Para32[0] = PortNumber;
		Para.Para32[1] = (SK_U32)-1;
		SkTimerStart(pAC, IoC, &pRPort->UpTimer, SK_RLMT_PORTUP_TIM_VAL,
			SKGE_RLMT, SK_RLMT_PORTUP_TIM, Para);
		pRPort->CheckingState &= ~SK_RLMT_PCS_RX;
		/* pAC->Rlmt.CheckSwitch = SK_TRUE; */
		SkRlmtCheckSwitch(pAC, IoC, pRPort->Net->NetNumber);
	}	/* PortDown && !SuspectTx */
	else if (pRPort->CheckingState & SK_RLMT_PCS_RX) {
		SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
			("SkRlmtPacketReceive: Stop bringing port down.\n"))
		SkTimerStop(pAC, IoC, &pRPort->DownRxTimer);
		pRPort->CheckingState &= ~SK_RLMT_PCS_RX;
		/* pAC->Rlmt.CheckSwitch = SK_TRUE; */
		SkRlmtCheckSwitch(pAC, IoC, pRPort->Net->NetNumber);
	}	/* PortGoingDown */

	return;
}	/* SkRlmtPortReceives */


/******************************************************************************
 *
 *	SkRlmtPacketReceive - receive a packet for closer examination
 *
 * Description:
 *	This routine examines a packet more closely than SK_RLMT_LOOKAHEAD.
 *
 * Context:
 *	runtime, pageable?
 *
 * Returns:
 *	Nothing.
 */
RLMT_STATIC void	SkRlmtPacketReceive(
SK_AC	*pAC,	/* Adapter Context */
SK_IOC	IoC,	/* I/O Context */
SK_MBUF	*pMb)	/* Received packet */
{
#ifdef xDEBUG
	extern	void DumpData(char *p, int size);
#endif	/* DEBUG */
	int					i;
	unsigned			j;
	SK_U16				PacketType;
	SK_U32				PortNumber;
	SK_ADDR_PORT		*pAPort;
	SK_RLMT_PORT		*pRPort;
	SK_RLMT_PACKET		*pRPacket;
	SK_SPTREE_PACKET	*pSPacket;
	SK_EVPARA			Para;

	PortNumber	= pMb->PortIdx;
	pAPort = &pAC->Addr.Port[PortNumber];
	pRPort = &pAC->Rlmt.Port[PortNumber];

	SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
		("SkRlmtPacketReceive: PortNumber == %d.\n", PortNumber))

	pRPacket = (SK_RLMT_PACKET*)pMb->pData;
	pSPacket = (SK_SPTREE_PACKET*)pRPacket;

#ifdef xDEBUG
	DumpData((char *)pRPacket, 32);
#endif	/* DEBUG */

	if ((pRPort->PacketsPerTimeSlot - pRPort->BpduPacketsPerTimeSlot) != 0) {
		SkRlmtPortReceives(pAC, IoC, PortNumber);
	}
	
	/* Check destination address. */

	if (!SK_ADDR_EQUAL(pAPort->CurrentMacAddress.a, pRPacket->DstAddr) &&
		!SK_ADDR_EQUAL(SkRlmtMcAddr.a, pRPacket->DstAddr) &&
		!SK_ADDR_EQUAL(BridgeMcAddr.a, pRPacket->DstAddr)) {

		/* Not sent to current MAC or registered MC address => Trash it. */
		SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
			("SkRlmtPacketReceive: Not for me.\n"))

		SkDrvFreeRlmtMbuf(pAC, IoC, pMb);
		return;
	}
	else if (SK_ADDR_EQUAL(pAPort->CurrentMacAddress.a, pRPacket->SrcAddr)) {

		/*
		 * Was sent by same port (may happen during port switching
		 * or in case of duplicate MAC addresses).
		 */

		/*
		 * Check for duplicate address here:
		 * If Packet.Random != My.Random => DupAddr.
		 */
		for (i = 3; i >= 0; i--) {
			if (pRPort->Random[i] != pRPacket->Random[i]) {
				break;
			}
		}

		/*
		 * CAUTION: Do not check for duplicate MAC address in RLMT Alive Reply
		 * packets (they have the LLC_COMMAND_RESPONSE_BIT set in
		 * pRPacket->SSap).
		 */
		if (i >= 0 && pRPacket->DSap == SK_RLMT_DSAP &&
			pRPacket->Ctrl == SK_RLMT_CTRL &&
			pRPacket->SSap == SK_RLMT_SSAP &&
			pRPacket->Indicator[0] == SK_RLMT_INDICATOR0 &&
			pRPacket->Indicator[1] == SK_RLMT_INDICATOR1 &&
			pRPacket->Indicator[2] == SK_RLMT_INDICATOR2 &&
			pRPacket->Indicator[3] == SK_RLMT_INDICATOR3 &&
			pRPacket->Indicator[4] == SK_RLMT_INDICATOR4 &&
			pRPacket->Indicator[5] == SK_RLMT_INDICATOR5 &&
			pRPacket->Indicator[6] == SK_RLMT_INDICATOR6) {
			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
				("SkRlmtPacketReceive: Duplicate MAC Address.\n"))

			/* Error Log entry. */
			SK_ERR_LOG(pAC, SK_ERRCL_COMM, SKERR_RLMT_E006, SKERR_RLMT_E006_MSG);
		}
		else {
			/* Simply trash it. */
			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
				("SkRlmtPacketReceive: Sent by me.\n"))
		}

		SkDrvFreeRlmtMbuf(pAC, IoC, pMb);
		return;
	}

	/* Check SuspectTx entries. */
	if (pRPort->PortsSuspect > 0) {
		for (j = 0; j < pRPort->PortsChecked; j++) {
			if (pRPort->PortCheck[j].SuspectTx &&
				SK_ADDR_EQUAL(
					pRPacket->SrcAddr, pRPort->PortCheck[j].CheckAddr.a)) {
				pRPort->PortCheck[j].SuspectTx = SK_FALSE;
				pRPort->PortsSuspect--;
				break;
			}
		}
	}

	/* Determine type of packet. */
	if (pRPacket->DSap == SK_RLMT_DSAP &&
		pRPacket->Ctrl == SK_RLMT_CTRL &&
		(pRPacket->SSap & ~LLC_COMMAND_RESPONSE_BIT) == SK_RLMT_SSAP &&
		pRPacket->Indicator[0] == SK_RLMT_INDICATOR0 &&
		pRPacket->Indicator[1] == SK_RLMT_INDICATOR1 &&
		pRPacket->Indicator[2] == SK_RLMT_INDICATOR2 &&
		pRPacket->Indicator[3] == SK_RLMT_INDICATOR3 &&
		pRPacket->Indicator[4] == SK_RLMT_INDICATOR4 &&
		pRPacket->Indicator[5] == SK_RLMT_INDICATOR5 &&
		pRPacket->Indicator[6] == SK_RLMT_INDICATOR6) {

		/* It's an RLMT packet. */
		PacketType = (SK_U16)((pRPacket->RlmtPacketType[0] << 8) |
			pRPacket->RlmtPacketType[1]);

		switch (PacketType) {
		case SK_PACKET_ANNOUNCE:	/* Not yet used. */
#if 0
			/* Build the check chain. */
			SkRlmtBuildCheckChain(pAC);
#endif	/* 0 */

			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
				("SkRlmtPacketReceive: Announce.\n"))

			SkDrvFreeRlmtMbuf(pAC, IoC, pMb);
			break;

		case SK_PACKET_ALIVE:
			if (pRPacket->SSap & LLC_COMMAND_RESPONSE_BIT) {
				SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
					("SkRlmtPacketReceive: Alive Reply.\n"))

				if (!(pAC->Addr.Port[PortNumber].PromMode & SK_PROM_MODE_LLC) ||
					SK_ADDR_EQUAL(
						pRPacket->DstAddr, pAPort->CurrentMacAddress.a)) {
					/* Obviously we could send something. */
					if (pRPort->CheckingState & SK_RLMT_PCS_TX) {
						pRPort->CheckingState &=  ~SK_RLMT_PCS_TX;
						SkTimerStop(pAC, IoC, &pRPort->DownTxTimer);
					}

					if ((pRPort->PortState == SK_RLMT_PS_DOWN) &&
						!(pRPort->CheckingState & SK_RLMT_PCS_RX)) {
						pRPort->PortState = SK_RLMT_PS_GOING_UP;
						pRPort->GuTimeStamp = SkOsGetTime(pAC);

						SkTimerStop(pAC, IoC, &pRPort->DownTxTimer);

						Para.Para32[0] = PortNumber;
						Para.Para32[1] = (SK_U32)-1;
						SkTimerStart(pAC, IoC, &pRPort->UpTimer,
							SK_RLMT_PORTUP_TIM_VAL, SKGE_RLMT,
							SK_RLMT_PORTUP_TIM, Para);
					}
				}

				/* Mark sending port as alive? */
				SkDrvFreeRlmtMbuf(pAC, IoC, pMb);
			}
			else {	/* Alive Request Packet. */
				SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
					("SkRlmtPacketReceive: Alive Request.\n"))

				pRPort->RxHelloCts++;

				/* Answer. */
				for (i = 0; i < SK_MAC_ADDR_LEN; i++) {
					pRPacket->DstAddr[i] = pRPacket->SrcAddr[i];
					pRPacket->SrcAddr[i] =
						pAC->Addr.Port[PortNumber].CurrentMacAddress.a[i];
				}
				pRPacket->SSap |= LLC_COMMAND_RESPONSE_BIT;

				Para.pParaPtr = pMb;
				SkEventQueue(pAC, SKGE_DRV, SK_DRV_RLMT_SEND, Para);
			}
			break;

		case SK_PACKET_CHECK_TX:
			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
				("SkRlmtPacketReceive: Check your tx line.\n"))

			/* A port checking us requests us to check our tx line. */
			pRPort->CheckingState |= SK_RLMT_PCS_TX;

			/* Start PortDownTx timer. */
			Para.Para32[0] = PortNumber;
			Para.Para32[1] = (SK_U32)-1;
			SkTimerStart(pAC, IoC, &pRPort->DownTxTimer,
				SK_RLMT_PORTDOWN_TIM_VAL, SKGE_RLMT,
				SK_RLMT_PORTDOWN_TX_TIM, Para);

			SkDrvFreeRlmtMbuf(pAC, IoC, pMb);

			if ((Para.pParaPtr = SkRlmtBuildPacket(pAC, IoC, PortNumber,
				SK_PACKET_ALIVE, &pAC->Addr.Port[PortNumber].CurrentMacAddress,
				&SkRlmtMcAddr)) != NULL) {
				SkEventQueue(pAC, SKGE_DRV, SK_DRV_RLMT_SEND, Para);
			}
			break;

		case SK_PACKET_ADDR_CHANGED:
			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
				("SkRlmtPacketReceive: Address Change.\n"))

			/* Build the check chain. */
			SkRlmtBuildCheckChain(pAC, pRPort->Net->NetNumber);
			SkDrvFreeRlmtMbuf(pAC, IoC, pMb);
			break;

		default:
			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
				("SkRlmtPacketReceive: Unknown RLMT packet.\n"))

			/* RA;:;: ??? */
			SkDrvFreeRlmtMbuf(pAC, IoC, pMb);
		}
	}
	else if (pSPacket->DSap == SK_RLMT_SPT_DSAP &&
		pSPacket->Ctrl == SK_RLMT_SPT_CTRL &&
		(pSPacket->SSap & ~LLC_COMMAND_RESPONSE_BIT) == SK_RLMT_SPT_SSAP) {
		SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,
			("SkRlmtPacketReceive: BPDU Packet.\n"))

		/* Spanning Tree packet. */
		pRPort->RxSpHelloCts++;

		if (!SK_ADDR_EQUAL(&pSPacket->RootId[2], &pAC->Addr.Net[pAC->Rlmt.
			Port[PortNumber].Net->NetNumber].CurrentMacAddress.a[0])) {
			/*
			 * Check segmentation if a new root bridge is set and
			 * the segmentation check is not currently running.
			 */
			if (!SK_ADDR_EQUAL(&pSPacket->RootId[2], &pRPort->Root.Id[2]) &&
				(pAC->Rlmt.Port[PortNumber].Net->LinksUp > 1) &&
				(pAC->Rlmt.Port[PortNumber].Net->RlmtMode & SK_RLMT_CHECK_SEG)
				!= 0 && (pAC->Rlmt.Port[PortNumber].Net->CheckingState &
				SK_RLMT_RCS_SEG) == 0) {
				pAC->Rlmt.Port[PortNumber].Net->CheckingState |=
					SK_RLMT_RCS_START_SEG | SK_RLMT_RCS_SEND_SEG;
			}

			/* Store tree view of this port. */
			for (i = 0; i < 8; i++) {
				pRPort->Root.Id[i] = pSPacket->RootId[i];
			}
			pRPort->RootIdSet = SK_TRUE;

			SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_DUMP,
				("Root ID %d: %02x %02x %02x %02x %02x %02x %02x %02x.\n",
					PortNumber,
					pRPort->Root.Id[0], pRPort->Root.Id[1],
					pRPort->Root.Id[2], pRPort->Root.Id[3],
					pRPort->Root.Id[4], pRPort->Root.Id[5],
					pRPort->Root.Id[6], pRPort->Root.Id[7]))      
		}

		SkDrvFreeRlmtMbuf(pAC, IoC, pMb);
		if ((pAC->Rlmt.Port[PortNumber].Net->CheckingState &
			SK_RLMT_RCS_REPORT_SEG) != 0) {
			SkRlmtCheckSeg(pAC, IoC, pAC->Rlmt.Port[PortNumber].Net->NetNumber);
		}
	}
	else {
		SK_DBG_MSG(pAC, SK_DBGMOD_RLMT, SK_DBGCAT_RX,