3 files changed, 26 insertions, 0 deletions

diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 8283cbdec50a..8f0d6d0c383b 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -101,6 +101,10 @@
                 netdev_adjacent_get_private(bond_slave_list(bond)->prev) : \
                 NULL)
 
+/* Caller must have rcu_read_lock */
+#define bond_first_slave_rcu(bond) \
+        netdev_lower_get_first_private_rcu(bond->dev)
+
 #define bond_is_first_slave(bond, pos) (pos == bond_first_slave(bond))
 #define bond_is_last_slave(bond, pos) (pos == bond_last_slave(bond))
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 5260d2eae2e6..2c74d20dad34 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2907,6 +2907,7 @@ void *netdev_lower_get_next_private_rcu(struct net_device *dev,
              priv = netdev_lower_get_next_private_rcu(dev, &(iter)))
 
 void *netdev_adjacent_get_private(struct list_head *adj_list);
+void *netdev_lower_get_first_private_rcu(struct net_device *dev);
 struct net_device *netdev_master_upper_dev_get(struct net_device *dev);
 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev);
 int netdev_upper_dev_link(struct net_device *dev, struct net_device *upper_dev);
diff --git a/net/core/dev.c b/net/core/dev.c
index c95d664b2b42..9d4369ece679 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4544,6 +4544,27 @@ void *netdev_lower_get_next_private_rcu(struct net_device *dev,
 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
 
 /**
+ * netdev_lower_get_first_private_rcu - Get the first ->private from the
+ *                                     lower neighbour list, RCU
+ *                                     variant
+ * @dev: device
+ *
+ * Gets the first netdev_adjacent->private from the dev's lower neighbour
+ * list. The caller must hold RCU read lock.
+ */
+void *netdev_lower_get_first_private_rcu(struct net_device *dev)
+{
+        struct netdev_adjacent *lower;
+
+        lower = list_first_or_null_rcu(&dev->adj_list.lower,
+                        struct netdev_adjacent, list);
+        if (lower)
+                return lower->private;
+        return NULL;
+}
+EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
+
+/**
  * netdev_master_upper_dev_get_rcu - Get master upper device
  * @dev: device
  *