Commit 6006f7f5 authored by Sergei Shtylyov's avatar Sergei Shtylyov Committed by Jeff Garzik
Browse files

natsemi: netpoll fixes 



Fix two issues in this driver's netpoll path: one usual, with spin_unlock_irq()
enabling interrupts which nobody asks it to do (that has been fixed recently in
a number of drivers) and one unusual, with poll_controller() method possibly
causing loss of interrupts due to the interrupt status register being cleared
by a simple read and the interrpupt handler simply storing it, not accumulating.

Signed-off-by: default avatarSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent a816c7c7

drivers/net/natsemi.c

+19 −5
Original line number Diff line number Diff line
@@ -2024,6 +2024,7 @@ static int start_tx(struct sk_buff *skb, struct net_device *dev) 
	struct netdev_private *np = netdev_priv(dev);

	void __iomem * ioaddr = ns_ioaddr(dev);

	unsigned entry;

	unsigned long flags;



	/* Note: Ordering is important here, set the field with the

	   "ownership" bit last, and only then increment cur_tx. */
@@ -2037,7 +2038,7 @@ static int start_tx(struct sk_buff *skb, struct net_device *dev) 


	np->tx_ring[entry].addr = cpu_to_le32(np->tx_dma[entry]);



	spin_lock_irq(&np->lock);

	spin_lock_irqsave(&np->lock, flags);



	if (!np->hands_off) {

		np->tx_ring[entry].cmd_status = cpu_to_le32(DescOwn | skb->len);
@@ -2056,7 +2057,7 @@ static int start_tx(struct sk_buff *skb, struct net_device *dev) 
		dev_kfree_skb_irq(skb);

		np->stats.tx_dropped++;

	}

	spin_unlock_irq(&np->lock);

	spin_unlock_irqrestore(&np->lock, flags);



	dev->trans_start = jiffies;
@@ -2222,6 +2223,8 @@ static void netdev_rx(struct net_device *dev, int *work_done, int work_to_do) 
		pkt_len = (desc_status & DescSizeMask) - 4;

		if ((desc_status&(DescMore|DescPktOK|DescRxLong)) != DescPktOK){

			if (desc_status & DescMore) {

				unsigned long flags;



				if (netif_msg_rx_err(np))

					printk(KERN_WARNING

						"%s: Oversized(?) Ethernet "
@@ -2236,12 +2239,12 @@ static void netdev_rx(struct net_device *dev, int *work_done, int work_to_do) 
				 * reset procedure documented in

				 * AN-1287. */



				spin_lock_irq(&np->lock);

				spin_lock_irqsave(&np->lock, flags);

				reset_rx(dev);

				reinit_rx(dev);

				writel(np->ring_dma, ioaddr + RxRingPtr);

				check_link(dev);

				spin_unlock_irq(&np->lock);

				spin_unlock_irqrestore(&np->lock, flags);



				/* We'll enable RX on exit from this

				 * function. */
@@ -2396,8 +2399,19 @@ static struct net_device_stats *get_stats(struct net_device *dev) 
#ifdef CONFIG_NET_POLL_CONTROLLER

static void natsemi_poll_controller(struct net_device *dev)

{

	struct netdev_private *np = netdev_priv(dev);



	disable_irq(dev->irq);



	/*

	 * A real interrupt might have already reached us at this point

	 * but NAPI might still haven't called us back.  As the interrupt

	 * status register is cleared by reading, we should prevent an

	 * interrupt loss in this case...

	 */

	if (!np->intr_status)

		intr_handler(dev->irq, dev);



	enable_irq(dev->irq);

}

#endif

CRA Git | Maintained and supported by SUSTech CRA and CCSE