net/core: add NETDEV_BONDING_FAILOVER event

Add NETDEV_BONDING_FAILOVER event to be used in a successive patch
by bonding to announce fail-over for the active-backup mode through the
netdev events notifier chain mechanism. Such an event can be of use for the
RDMA CM (communication manager) to let native RDMA ULPs (eg NFS-RDMA, iSER)
always be aligned with the IP stack, in the sense that they use the same
ports/links as the stack does. More usages can be done to allow monitoring
tools based on netlink events being aware to bonding fail-over.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 68d8df0992ab..0e45742e7158 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -961,6 +961,12 @@ void netdev_state_change(struct net_device *dev)
         }
 }
 
+void netdev_bonding_change(struct net_device *dev)
+{
+        call_netdevice_notifiers(NETDEV_BONDING_FAILOVER, dev);
+}
+EXPORT_SYMBOL(netdev_bonding_change);
+
 /**
  *      dev_load        - load a network module
  *      @net: the applicable net namespace