Merge remote-tracking branches 'asoc/topic/cs47l24', 'asoc/topic/cx20442', 'asoc...

[sfrench/cifs-2.6.git] / drivers / infiniband / ulp / ipoib / ipoib_main.c

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 12b7f911f0e5b9b9fce4f034bde66db4fcc26e81..8880351df179382fa6d64b4b6e698c2fdb563e94 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -902,8 +902,8 @@ static int path_rec_start(struct net_device *dev,
        return 0;
 }
 
-static void neigh_add_path(struct sk_buff *skb, u8 *daddr,
-                          struct net_device *dev)
+static struct ipoib_neigh *neigh_add_path(struct sk_buff *skb, u8 *daddr,
+                                         struct net_device *dev)
 {
        struct ipoib_dev_priv *priv = ipoib_priv(dev);
        struct rdma_netdev *rn = netdev_priv(dev);
@@ -917,7 +917,15 @@ static void neigh_add_path(struct sk_buff *skb, u8 *daddr,
                spin_unlock_irqrestore(&priv->lock, flags);
                ++dev->stats.tx_dropped;
                dev_kfree_skb_any(skb);
-               return;
+               return NULL;
+       }
+
+       /* To avoid race condition, make sure that the
+        * neigh will be added only once.
+        */
+       if (unlikely(!list_empty(&neigh->list))) {
+               spin_unlock_irqrestore(&priv->lock, flags);
+               return neigh;
        }
 
        path = __path_find(dev, daddr + 4);
@@ -956,7 +964,7 @@ static void neigh_add_path(struct sk_buff *skb, u8 *daddr,
                        path->ah->last_send = rn->send(dev, skb, path->ah->ah,
                                                       IPOIB_QPN(daddr));
                        ipoib_neigh_put(neigh);
-                       return;
+                       return NULL;
                }
        } else {
                neigh->ah  = NULL;
@@ -973,7 +981,7 @@ static void neigh_add_path(struct sk_buff *skb, u8 *daddr,
 
        spin_unlock_irqrestore(&priv->lock, flags);
        ipoib_neigh_put(neigh);
-       return;
+       return NULL;
 
 err_path:
        ipoib_neigh_free(neigh);
@@ -983,6 +991,8 @@ err_drop:
 
        spin_unlock_irqrestore(&priv->lock, flags);
        ipoib_neigh_put(neigh);
+
+       return NULL;
 }
 
 static void unicast_arp_send(struct sk_buff *skb, struct net_device *dev,
@@ -1091,8 +1101,9 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
        case htons(ETH_P_TIPC):
                neigh = ipoib_neigh_get(dev, phdr->hwaddr);
                if (unlikely(!neigh)) {
-                       neigh_add_path(skb, phdr->hwaddr, dev);
-                       return NETDEV_TX_OK;
+                       neigh = neigh_add_path(skb, phdr->hwaddr, dev);
+                       if (likely(!neigh))
+                               return NETDEV_TX_OK;
                }
                break;
        case htons(ETH_P_ARP):