[PATCH 4/5] UBUNTU: SAUCE: net: calxedaxgmac: add mac address learning

Andy Whitcroft apw at canonical.com
Thu Nov 7 14:24:09 UTC 2013


On Wed, Nov 06, 2013 at 03:34:46PM +0100, Paolo Pisati wrote:
> From: Rob Herring <rob.herring at calxeda.com>
> 
> BugLink: http://bugs.launchpad.net/bugs/1248504
> 
> The Calxeda xgmac must learn secondary mac addresses such as those
> behind a bridge in order to properly receive packets with those mac
> addresses. Add mac address learning on transmit with aging of entries.
> The mac addresses are added to the driver's unicast address list, so
> they are visible to user via "bridge fdb show" command.
> 
> Signed-off-by: Rob Herring <rob.herring at calxeda.com>
> Signed-off-by: Paolo Pisati <paolo.pisati at canonical.com>
> ---
>  drivers/net/ethernet/calxeda/xgmac.c | 102 ++++++++++++++++++++++++++++++++++-
>  1 file changed, 101 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/calxeda/xgmac.c b/drivers/net/ethernet/calxeda/xgmac.c
> index 48f5288..4c0f469 100644
> --- a/drivers/net/ethernet/calxeda/xgmac.c
> +++ b/drivers/net/ethernet/calxeda/xgmac.c
> @@ -360,6 +360,13 @@ struct xgmac_extra_stats {
>  	unsigned long rx_process_stopped;
>  	unsigned long tx_early;
>  	unsigned long fatal_bus_error;
> +	unsigned long learning_drop;
> +};
> +
> +struct xgmac_mac {
> +	char mac_addr[ETH_ALEN];
> +	unsigned long time;
> +	int reg_idx;
>  };
>  
>  struct xgmac_priv {
> @@ -384,6 +391,8 @@ struct xgmac_priv {
>  	struct napi_struct napi;
>  
>  	int max_macs;
> +	struct xgmac_mac mac_list[32];
> +
>  	struct xgmac_extra_stats xstats;
>  
>  	spinlock_t stats_lock;
> @@ -392,8 +401,11 @@ struct xgmac_priv {
>  	char tx_pause;
>  	int wolopts;
>  	struct work_struct tx_timeout_work;
> +	struct delayed_work mac_aging_work;
>  };
>  
> +#define XGMAC_AGING_TIMEOUT	(120 * HZ)

Is this even used?

> +
>  /* XGMAC Configuration Settings */
>  #define MAX_MTU			9000
>  #define PAUSE_TIME		0x400
> @@ -634,7 +646,7 @@ static void xgmac_set_mac_addr(void __iomem *ioaddr, unsigned char *addr,
>  	}
>  }
>  
> -static void xgmac_get_mac_addr(void __iomem *ioaddr, unsigned char *addr,
> +static bool xgmac_get_mac_addr(void __iomem *ioaddr, unsigned char *addr,
>  			       int num)
>  {
>  	u32 hi_addr, lo_addr;
> @@ -650,6 +662,8 @@ static void xgmac_get_mac_addr(void __iomem *ioaddr, unsigned char *addr,
>  	addr[3] = (lo_addr >> 24) & 0xff;
>  	addr[4] = hi_addr & 0xff;
>  	addr[5] = (hi_addr >> 8) & 0xff;
> +
> +	return (hi_addr & XGMAC_ADDR_AE) ? true : false;
>  }
>  
>  static int xgmac_set_flow_ctrl(struct xgmac_priv *priv, int rx, int tx)
> @@ -1047,6 +1061,8 @@ static int xgmac_open(struct net_device *dev)
>  	writel(DMA_INTR_DEFAULT_MASK, ioaddr + XGMAC_DMA_STATUS);
>  	writel(DMA_INTR_DEFAULT_MASK, ioaddr + XGMAC_DMA_INTR_ENA);
>  
> +	schedule_delayed_work(&priv->mac_aging_work, 5 * HZ);
> +
>  	return 0;
>  }
>  
> @@ -1059,6 +1075,7 @@ static int xgmac_open(struct net_device *dev)
>  static int xgmac_stop(struct net_device *dev)
>  {
>  	struct xgmac_priv *priv = netdev_priv(dev);
> +	int i;
>  
>  	netif_stop_queue(dev);
>  
> @@ -1073,9 +1090,87 @@ static int xgmac_stop(struct net_device *dev)
>  	/* Release and free the Rx/Tx resources */
>  	xgmac_free_dma_desc_rings(priv);
>  
> +	cancel_delayed_work_sync(&priv->mac_aging_work);
> +	for (i = 0; i < priv->max_macs; i++) {
> +		if (!is_valid_ether_addr(priv->mac_list[i].mac_addr))
> +			continue;
> +		priv->mac_list[i].time = 0;
> +		dev_uc_del(dev, priv->mac_list[i].mac_addr);
> +		memset(priv->mac_list[i].mac_addr, 0, ETH_ALEN);
> +	}
> +
>  	return 0;
>  }
>  
> +static void xgmac_mac_aging_work(struct work_struct *work)
> +{
> +	int i, j;
> +	char addr[ETH_ALEN];
> +	struct xgmac_priv *priv =
> +		container_of(work, struct xgmac_priv, mac_aging_work.work);
> +	struct net_device *dev = priv->dev;
> +
> +	for (i = 1; i < priv->max_macs; i++) {
> +		if (xgmac_get_mac_addr(priv->base, addr, i))
> +			continue;
> +
> +		if (!is_valid_ether_addr(addr))
> +			break;
> +
> +		dev_uc_del(dev, addr);
> +		//printk("unlearned addr %pM\n", addr);
> +
> +		for (j = 1; j < priv->max_macs; j++) {
> +			if (!ether_addr_equal(addr, priv->mac_list[j].mac_addr))
> +				continue;
> +			priv->mac_list[i].time = 0;
> +			memset(priv->mac_list[i].mac_addr, 0, ETH_ALEN);
> +			break;

This routine seems to search through the addresses configured on the
device, and where they are found and removed we then seem to search our
locla mac_list[] array for them and remove them there as well.  It looks
to my eye that we find the appropriate slot in this inner loop and
remove the entry defined by the outer one.

Could you check with Rob, as either this code is wrong, or it is subtle
enough that it needs a comment to explain it.

> +		}
> +	}
> +
> +	schedule_delayed_work(to_delayed_work(work), 5 * HZ);
> +}
> +
> +static void xgmac_learn_mac(struct xgmac_priv *priv, struct sk_buff *skb)
> +{
> +	struct net_device *dev = priv->dev;
> +	struct ethhdr *phdr = (struct ethhdr *)(skb->data);
> +	char *src_addr = phdr->h_source;
> +	int i, slot = -1, oldest_slot = -1;
> +	unsigned long oldest_time = jiffies;
> +
> +	if (ether_addr_equal(src_addr, dev->dev_addr) ||
> +	    !is_valid_ether_addr(src_addr))
> +		return;
> +
> +	for (i = 0; i < priv->max_macs; i++) {
> +		/* update timestamp if we already learned the address */
> +		if (ether_addr_equal(priv->mac_list[i].mac_addr, src_addr)) {
> +			priv->mac_list[i].time = jiffies;
> +			return;
> +		}
> +		/* find empty slot */
> +		if (slot >= 0)
> +			continue;
> +		if (!priv->mac_list[i].time)
> +			slot = i;
> +		else if (time_before(priv->mac_list[i].time, oldest_time)) {
> +			oldest_time = priv->mac_list[i].time;
> +			oldest_slot = i;
> +		}
> +	}
> +	if ((slot < 0) && (oldest_slot >= 0)) {
> +		slot = oldest_slot;
> +		priv->xstats.learning_drop++;
> +	}
> +
> +	//printk("learned addr %pM\n", src_addr);
> +	memcpy(priv->mac_list[slot].mac_addr, src_addr, ETH_ALEN);
> +	dev_uc_add_excl(dev, src_addr);
> +	priv->mac_list[slot].time = jiffies;
> +}
> +
>  /**
>   *  xgmac_xmit:
>   *  @skb : the socket buffer
> @@ -1155,6 +1250,9 @@ static netdev_tx_t xgmac_xmit(struct sk_buff *skb, struct net_device *dev)
>  		if (tx_dma_ring_space(priv) > MAX_SKB_FRAGS)
>  			netif_start_queue(dev);
>  	}
> +
> +	xgmac_learn_mac(priv, skb);
> +
>  	return NETDEV_TX_OK;
>  
>  dma_err:
> @@ -1605,6 +1703,7 @@ static const struct xgmac_stats xgmac_gstrings_stats[] = {
>  	XGMAC_STAT(rx_ip_header_error),
>  	XGMAC_STAT(rx_da_filter_fail),
>  	XGMAC_STAT(fatal_bus_error),
> +	XGMAC_STAT(learning_drop),
>  	XGMAC_HW_STAT(rx_watchdog, XGMAC_MMC_RXWATCHDOG),
>  	XGMAC_HW_STAT(tx_vlan, XGMAC_MMC_TXVLANFRAME),
>  	XGMAC_HW_STAT(rx_vlan, XGMAC_MMC_RXVLANFRAME),
> @@ -1743,6 +1842,7 @@ static int xgmac_probe(struct platform_device *pdev)
>  	SET_ETHTOOL_OPS(ndev, &xgmac_ethtool_ops);
>  	spin_lock_init(&priv->stats_lock);
>  	INIT_WORK(&priv->tx_timeout_work, xgmac_tx_timeout_work);
> +	INIT_DELAYED_WORK(&priv->mac_aging_work, xgmac_mac_aging_work);
>  
>  	priv->device = &pdev->dev;
>  	priv->dev = ndev;
> -- 
> 1.8.3.2
> 
> 
> -- 
> kernel-team mailing list
> kernel-team at lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team

-apw




More information about the kernel-team mailing list