net: track link-status of ipv4 nexthops
Add a fib flag called RTNH_F_LINKDOWN to any ipv4 nexthops that are
reachable via an interface where carrier is off. No action is taken,
but additional flags are passed to userspace to indicate carrier status.
This also includes a cleanup to fib_disable_ip to more clearly indicate
what event made the function call to replace the more cryptic force
option previously used.
v2: Split out kernel functionality into 2 patches, this patch simply
sets and clears new nexthop flag RTNH_F_LINKDOWN.
v3: Cleanups suggested by Alex as well as a bug noticed in
fib_sync_down_dev and fib_sync_up when multipath was not enabled.
v5: Whitespace and variable declaration fixups suggested by Dave.
v6: Style fixups noticed by Dave; ran checkpatch to be sure I got them
all.
Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 872494e..534eb14 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -1063,9 +1063,9 @@
net->ipv4.fibnl = NULL;
}
-static void fib_disable_ip(struct net_device *dev, int force)
+static void fib_disable_ip(struct net_device *dev, unsigned long event)
{
- if (fib_sync_down_dev(dev, force))
+ if (fib_sync_down_dev(dev, event))
fib_flush(dev_net(dev));
rt_cache_flush(dev_net(dev));
arp_ifdown(dev);
@@ -1081,7 +1081,7 @@
case NETDEV_UP:
fib_add_ifaddr(ifa);
#ifdef CONFIG_IP_ROUTE_MULTIPATH
- fib_sync_up(dev);
+ fib_sync_up(dev, RTNH_F_DEAD);
#endif
atomic_inc(&net->ipv4.dev_addr_genid);
rt_cache_flush(dev_net(dev));
@@ -1093,7 +1093,7 @@
/* Last address was deleted from this interface.
* Disable IP.
*/
- fib_disable_ip(dev, 1);
+ fib_disable_ip(dev, event);
} else {
rt_cache_flush(dev_net(dev));
}
@@ -1107,9 +1107,10 @@
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct in_device *in_dev;
struct net *net = dev_net(dev);
+ unsigned int flags;
if (event == NETDEV_UNREGISTER) {
- fib_disable_ip(dev, 2);
+ fib_disable_ip(dev, event);
rt_flush_dev(dev);
return NOTIFY_DONE;
}
@@ -1124,16 +1125,22 @@
fib_add_ifaddr(ifa);
} endfor_ifa(in_dev);
#ifdef CONFIG_IP_ROUTE_MULTIPATH
- fib_sync_up(dev);
+ fib_sync_up(dev, RTNH_F_DEAD);
#endif
atomic_inc(&net->ipv4.dev_addr_genid);
rt_cache_flush(net);
break;
case NETDEV_DOWN:
- fib_disable_ip(dev, 0);
+ fib_disable_ip(dev, event);
break;
- case NETDEV_CHANGEMTU:
case NETDEV_CHANGE:
+ flags = dev_get_flags(dev);
+ if (flags & (IFF_RUNNING | IFF_LOWER_UP))
+ fib_sync_up(dev, RTNH_F_LINKDOWN);
+ else
+ fib_sync_down_dev(dev, event);
+ /* fall through */
+ case NETDEV_CHANGEMTU:
rt_cache_flush(net);
break;
}