From 982acb97560c8118c2109504a22b0d78a580547d Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Wed, 8 Feb 2017 11:16:39 +0100 Subject: ipv4: fib: Notify about nexthop status changes When a multipath route is hit the kernel doesn't consider nexthops that are DEAD or LINKDOWN when IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN is set. Devices that offload multipath routes need to be made aware of nexthop status changes. Otherwise, the device will keep forwarding packets to non-functional nexthops. Add the FIB_EVENT_NH_{ADD,DEL} events to the fib notification chain, which notify capable devices when they should add or delete a nexthop from their tables. Cc: Roopa Prabhu Cc: David Ahern Cc: Andy Gospodarek Signed-off-by: Ido Schimmel Signed-off-by: Jiri Pirko Reviewed-by: Andy Gospodarek Signed-off-by: David S. Miller --- net/ipv4/fib_semantics.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'net/ipv4') diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 6306a67880e8..317026a39cfa 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -1355,6 +1355,36 @@ int fib_sync_down_addr(struct net_device *dev, __be32 local) return ret; } +static int call_fib_nh_notifiers(struct fib_nh *fib_nh, + enum fib_event_type event_type) +{ + struct in_device *in_dev = __in_dev_get_rtnl(fib_nh->nh_dev); + struct fib_nh_notifier_info info = { + .fib_nh = fib_nh, + }; + + switch (event_type) { + case FIB_EVENT_NH_ADD: + if (fib_nh->nh_flags & RTNH_F_DEAD) + break; + if (IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) && + fib_nh->nh_flags & RTNH_F_LINKDOWN) + break; + return call_fib_notifiers(dev_net(fib_nh->nh_dev), event_type, + &info.info); + case FIB_EVENT_NH_DEL: + if ((IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) && + fib_nh->nh_flags & RTNH_F_LINKDOWN) || + (fib_nh->nh_flags & RTNH_F_DEAD)) + return call_fib_notifiers(dev_net(fib_nh->nh_dev), + event_type, &info.info); + default: + break; + } + + return NOTIFY_DONE; +} + /* Event force Flags Description * NETDEV_CHANGE 0 LINKDOWN Carrier OFF, not for scope host * NETDEV_DOWN 0 LINKDOWN|DEAD Link down, not for scope host @@ -1396,6 +1426,8 @@ int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force) nexthop_nh->nh_flags |= RTNH_F_LINKDOWN; break; } + call_fib_nh_notifiers(nexthop_nh, + FIB_EVENT_NH_DEL); dead++; } #ifdef CONFIG_IP_ROUTE_MULTIPATH @@ -1550,6 +1582,7 @@ int fib_sync_up(struct net_device *dev, unsigned int nh_flags) continue; alive++; nexthop_nh->nh_flags &= ~nh_flags; + call_fib_nh_notifiers(nexthop_nh, FIB_EVENT_NH_ADD); } endfor_nexthops(fi) if (alive > 0) { -- cgit v1.2.3