vxlan: break dependency with netdev drivers

Currently all drivers depend and autoload the vxlan module because how
vxlan_get_rx_port is linked into them. Remove this dependency:

By using a new event type in the netdevice notifier call chain we proxy
the request from the drivers to flush and resetup the vxlan ports not
directly via function call but by the already existing netdevice
notifier call chain.

I added a separate new event type, NETDEV_OFFLOAD_PUSH_VXLAN, to do so.
We don't need to save those ids, as the event type field is an unsigned
long and using specialized event types for this purpose seemed to be a
more elegant way. This also comes in beneficial if in future we want to
add offloading knobs for vxlan.

Cc: Jesse Gross <jesse@kernel.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index a3bb534576a3..d4c8cd424f8d 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2244,6 +2244,7 @@ struct netdev_lag_lower_state_info {
 #define NETDEV_BONDING_INFO	0x0019
 #define NETDEV_PRECHANGEUPPER	0x001A
 #define NETDEV_CHANGELOWERSTATE	0x001B
+#define NETDEV_OFFLOAD_PUSH_VXLAN	0x001C
 
 int register_netdevice_notifier(struct notifier_block *nb);
 int unregister_netdevice_notifier(struct notifier_block *nb);