bridge: Fix the way the PVID is referenced

We are using the VLAN_TAG_PRESENT bit to detect whether the PVID is
set or not at br_get_pvid(), while we don't care about the bit in
adding/deleting the PVID, which makes it impossible to forward any
incomming untagged frame with vlan_filtering enabled.

Since vid 0 cannot be used for the PVID, we can use vid 0 to indicate
that the PVID is not set, which is slightly more efficient than using
the VLAN_TAG_PRESENT.

Fix the problem by getting rid of using the VLAN_TAG_PRESENT.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Reviewed-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index efb57d91156975b3b43a2afdc588128a2f6e1f79..7ca2ae45b2d59e5dc9bc85e00f58480b2f00f3e3 100644 (file)
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -643,9 +643,7 @@ static inline u16 br_get_pvid(const struct net_port_vlans *v)
         * vid wasn't set
         */
        smp_rmb();
-       return (v->pvid & VLAN_TAG_PRESENT) ?
-                       (v->pvid & ~VLAN_TAG_PRESENT) :
-                       VLAN_N_VID;
+       return v->pvid ?: VLAN_N_VID;
 }
 
 #else