bonding: add __bond_next_slave() which uses neighbours

Add a new function, __bond_next_slave(), which uses neighbours to find the
next slave after the slave provided. It will be further used to gradually
go start using neighbour netdev_adjacent infrastructure instead of
bonding's own lists.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 454d6affa06a44edb6287cf853f001740bde15b7..4a3fbe307ee809c3ca0d2c98d5000b335bc07756 100644 (file)
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -249,6 +249,34 @@ struct bonding {
 #define bond_slave_get_rtnl(dev) \
        ((struct slave *) rtnl_dereference(dev->rx_handler_data))
 
+/**
+ * __bond_next_slave - get the next slave after the one provided
+ * @bond - bonding struct
+ * @slave - the slave provided
+ *
+ * Returns the next slave after the slave provided, first slave if the
+ * slave provided is the last slave and NULL if slave is not found
+ */
+static inline struct slave *__bond_next_slave(struct bonding *bond,
+                                             struct slave *slave)
+{
+       struct slave *slave_iter;
+       struct list_head *iter;
+       bool found = false;
+
+       netdev_for_each_lower_private(bond->dev, slave_iter, iter) {
+               if (found)
+                       return slave_iter;
+               if (slave_iter == slave)
+                       found = true;
+       }
+
+       if (found)
+               return bond_first_slave(bond);
+
+       return NULL;
+}
+
 /**
  * Returns NULL if the net_device does not belong to any of the bond's slaves
  *