[PATCH] (15/25) sk98: handle tranmit ring full

@@ -1354,67 +1354,47 @@
  * Description:
  *	The system calls this function to send frames onto the wire.
  *	It puts the frame in the tx descriptor ring. If the ring is
- *	full then, the 'tbusy' flag is set.
+ *	full then, the it returns busy and leaves skb alone.
  *
  * Returns:
- *	0, if everything is ok
- *	!=0, on error
- * WARNING: returning 1 in 'tbusy' case caused system crashes (double
- *	allocated skb's) !!!
+ *	0 (NETDEV_TX_OK) 	if everything is ok
+ *	1 (NETDEV_TX_BUSY) 	if ring is full
  */
 int SkGeXmit(struct sk_buff *skb, struct net_device *dev)
 {
-DEV_NET		*pNet;
-SK_AC		*pAC;
-int			Rc;	/* return code of XmitFrame */
-
-	pNet = netdev_priv(dev);
-	pAC = pNet->pAC;
+	DEV_NET	*pNet = netdev_priv(dev);
+	SK_AC	*pAC = pNet->pAC;
+	TX_PORT		*pTxPort;
+	int	rc;
+	unsigned long flags;
+ 
+	if (pAC->RlmtNets == 2)
+		pTxPort = &pAC->TxPort[pNet->PortNr][TX_PRIO_LOW];
+	else
+		pTxPort = &pAC->TxPort[pAC->ActivePort][TX_PRIO_LOW];
+ 
+	spin_lock_irqsave(&pTxPort->TxDesRingLock, flags);
 
 	if ((!skb_shinfo(skb)->nr_frags) ||
-		(pAC->GIni.GIChipId == CHIP_ID_GENESIS)) {
-		/* Don't activate scatter-gather and hardware checksum */
-
-		if (pAC->RlmtNets == 2)
-			Rc = XmitFrame(
-				pAC,
-				&pAC->TxPort[pNet->PortNr][TX_PRIO_LOW],
-				skb);
-		else
-			Rc = XmitFrame(
-				pAC,
-				&pAC->TxPort[pAC->ActivePort][TX_PRIO_LOW],
-				skb);
-	} else {
-		/* scatter-gather and hardware TCP checksumming anabled*/
-		if (pAC->RlmtNets == 2)
-			Rc = XmitFrameSG(
-				pAC,
-				&pAC->TxPort[pNet->PortNr][TX_PRIO_LOW],
-				skb);
-		else
-			Rc = XmitFrameSG(
-				pAC,
-				&pAC->TxPort[pAC->ActivePort][TX_PRIO_LOW],
-				skb);
-	}
-
-	/* Transmitter out of resources? */
-	if (Rc <= 0) {
+	    (pAC->GIni.GIChipId == CHIP_ID_GENESIS)) 
+		rc = XmitFrame(pAC, pTxPort, skb);
+	else 
+		rc = XmitFrameSG(pAC, pTxPort, skb);
+  
+	/* is space left for next transmit? */
+	if (rc <= 0) 
 		netif_stop_queue(dev);
-	}
+  
+	spin_unlock_irqrestore(&pTxPort->TxDesRingLock, flags);
+ 
+	/* Transmit failed, out of resources */
+	if (unlikely(rc < 0)) 
+		return NETDEV_TX_BUSY;
 
-	/* If not taken, give buffer ownership back to the
-	 * queueing layer.
-	 */
-	if (Rc < 0)
-		return (1);
-
-	dev->trans_start = jiffies;
-	return (0);
+	dev->trans_start = jiffies;		
+	return NETDEV_TX_OK;
 } /* SkGeXmit */
 
-
 /*****************************************************************************
  *
  * 	XmitFrame - fill one socket buffer into the transmit ring

@@ -1444,7 +1424,6 @@
 {
 	TXD		*pTxd;		/* the rxd to fill */
 	TXD		*pOldTxd;
-	unsigned long	 Flags;
 	SK_U64		 PhysAddr;
 	int	 	 Protocol;
 	int		 IpHeaderLength;

@@ -1452,7 +1431,6 @@
 
 	SK_DBG_MSG(NULL, SK_DBGMOD_DRV, SK_DBGCAT_DRV_TX_PROGRESS, ("X"));
 
-	spin_lock_irqsave(&pTxPort->TxDesRingLock, Flags);
 #ifndef USE_TX_COMPLETE
 	FreeTxDescriptors(pAC, pTxPort);
 #endif

@@ -1463,7 +1441,6 @@
 		*/
 		FreeTxDescriptors(pAC, pTxPort);
 		if (pTxPort->TxdRingFree == 0) {
-			spin_unlock_irqrestore(&pTxPort->TxDesRingLock, Flags);
 			SK_PNMI_CNT_NO_TX_BUF(pAC, pTxPort->PortIndex);
 			SK_DBG_MSG(NULL, SK_DBGMOD_DRV,
 				SK_DBGCAT_DRV_TX_PROGRESS,

@@ -1486,7 +1463,6 @@
 	*/
 	if (BytesSend < C_LEN_ETHERNET_MINSIZE) {
 		if ((pMessage = skb_padto(pMessage, C_LEN_ETHERNET_MINSIZE)) == NULL) {
-			spin_unlock_irqrestore(&pTxPort->TxDesRingLock, Flags);
 			return 0;
 		}
 		pMessage->len = C_LEN_ETHERNET_MINSIZE;

@@ -1561,16 +1537,7 @@
 		SK_OUT8(pTxPort->HwAddr, Q_CSR, CSR_START);
 	}	
 
-	/* 
-	** after releasing the lock, the skb may immediately be free'd 
-	*/
-	spin_unlock_irqrestore(&pTxPort->TxDesRingLock, Flags);
-	if (pTxPort->TxdRingFree != 0) {
-		return (BytesSend);
-	} else {
-		return (0);
-	}
-
+	return (pTxPort->TxdRingFree != 0);
 } /* XmitFrame */
 
 /*****************************************************************************

@@ -1603,16 +1570,13 @@
 	int		 Protocol;
 	skb_frag_t	*sk_frag;
 	SK_U64		 PhysAddr;
-	unsigned long	 Flags;
 
-	spin_lock_irqsave(&pTxPort->TxDesRingLock, Flags);
 #ifndef USE_TX_COMPLETE
 	FreeTxDescriptors(pAC, pTxPort);
 #endif
 	if ((skb_shinfo(pMessage)->nr_frags +1) > pTxPort->TxdRingFree) {
 		FreeTxDescriptors(pAC, pTxPort);
 		if ((skb_shinfo(pMessage)->nr_frags + 1) > pTxPort->TxdRingFree) {
-			spin_unlock_irqrestore(&pTxPort->TxDesRingLock, Flags);
 			SK_PNMI_CNT_NO_TX_BUF(pAC, pTxPort->PortIndex);
 			SK_DBG_MSG(NULL, SK_DBGMOD_DRV,
 				SK_DBGCAT_DRV_TX_PROGRESS,

@@ -1744,13 +1708,7 @@
 	pTxPort->pTxdRingPrev = pTxdLst;
 	pTxPort->pTxdRingHead = pTxd;
 
-	spin_unlock_irqrestore(&pTxPort->TxDesRingLock, Flags);
-
-	if (pTxPort->TxdRingFree > 0) {
-		return (BytesSend);
-	} else {
-		return (0);
-	}
+	return (pTxPort->TxdRingFree > 0);
 }
 
 /*****************************************************************************