From 2e477c9bd2bb6a1606e498adb53ba913378ecdf2 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 20 Jul 2009 07:35:37 -0700 Subject: [PATCH] vlan: Propagate physical MTU changes When the physical MTU changes we want to ensure that all existing VLAN device MTUs do not exceed the new underlying MTU. This patch adds that propagation. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/8021q/vlan.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c index fe649081fbdc..6d37b7e2a767 100644 --- a/net/8021q/vlan.c +++ b/net/8021q/vlan.c @@ -468,6 +468,19 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event, } break; + case NETDEV_CHANGEMTU: + for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) { + vlandev = vlan_group_get_device(grp, i); + if (!vlandev) + continue; + + if (vlandev->mtu <= dev->mtu) + continue; + + dev_set_mtu(vlandev, dev->mtu); + } + break; + case NETDEV_FEAT_CHANGE: /* Propagate device features to underlying device */ for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {