[PATCH 4/6] net/x25: support NETDEV_CHANGE notifier

[Martin Schiller <ms@dev.tdt.de>]

This makes it possible to handle carrier lost and detection.
In case of carrier lost, we shutdown layer 3 and flush all sessions.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
---
 net/x25/af_x25.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index d98d1145500e..d61a154b94e4 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -266,6 +266,17 @@ static int x25_device_event(struct notifier_block *this, unsigned long event,
 			pr_debug("X.25: got event NETDEV_UNREGISTER for device: %s\n", dev->name);
 			x25_link_device_remove(dev);
 			break;
+		case NETDEV_CHANGE:
+			pr_debug("X.25: got event NETDEV_CHANGE for device: %s\n", dev->name);
+			if (!netif_carrier_ok(dev)) {
+				pr_debug("X.25: Carrier lost -> set link state down: %s\n", dev->name);
+				nb = x25_get_neigh(dev);
+				if (nb) {
+					x25_link_terminated(nb);
+					x25_neigh_put(nb);
+				}
+			}
+			break;
 		}
 	}
 
-- 
2.20.1