[RFC PATCH v2 net-next 12/17] net: dsa: sync static FDB entries on foreign interfaces to hardware

[Vladimir Oltean <olteanv@gmail.com>]

From: Tobias Waldekranz <tobias@waldekranz.com>

Reuse the "assisted_learning_on_cpu_port" functionality to always add
entries for user-configured entries on foreign interfaces, even if
assisted_learning_on_cpu_port is not enabled. E.g. in this situation:

   br0
   / \
swp0 dummy0

$ bridge fdb add 02:00:de:ad:00:01 dev dummy0 vlan 1 master static

Results in DSA adding an entry in the hardware FDB, pointing this
address towards the CPU port.

The same is true for entries added to the bridge itself, e.g:

$ bridge fdb add 02:00:de:ad:00:01 dev br0 vlan 1 self local

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 net/dsa/slave.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 425b3223b7d1..a32875d3dc5f 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2556,9 +2556,12 @@ static int dsa_slave_switchdev_event(struct notifier_block *unused,
 			else if (!fdb_info->added_by_user)
 				return NOTIFY_OK;
 		} else {
-			/* Snoop addresses learnt on foreign interfaces
-			 * bridged with us, for switches that don't
-			 * automatically learn SA from CPU-injected traffic
+			/* Snoop addresses added to foreign interfaces
+			 * bridged with us, or the bridge
+			 * itself. Dynamically learned addresses can
+			 * also be added for switches that don't
+			 * automatically learn SA from CPU-injected
+			 * traffic.
 			 */
 			struct net_device *br_dev;
 			struct dsa_slave_priv *p;
@@ -2581,7 +2584,8 @@ static int dsa_slave_switchdev_event(struct notifier_block *unused,
 			dp = p->dp;
 			host_addr = true;
 
-			if (!dp->ds->assisted_learning_on_cpu_port)
+			if (!fdb_info->added_by_user &&
+			    !dp->ds->assisted_learning_on_cpu_port)
 				return NOTIFY_DONE;
 
 			/* When the bridge learns an address on an offloaded
-- 
2.25.1