bridge: respect RFC2863 operational state

The bridge link detection should follow the operational state
of the lower device, rather than the carrier bit. This allows devices
like tunnels that are controlled by userspace control plane to work
with bridge STP link management.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Reviewed-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index 37fe693..1edd71d 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -66,14 +66,14 @@
 	struct net_device *dev = p->dev;
 	struct net_bridge *br = p->br;
 
-	if (netif_running(dev) && netif_carrier_ok(dev))
+	if (netif_running(dev) && netif_oper_up(dev))
 		p->path_cost = port_cost(dev);
 
 	if (!netif_running(br->dev))
 		return;
 
 	spin_lock_bh(&br->lock);
-	if (netif_running(dev) && netif_carrier_ok(dev)) {
+	if (netif_running(dev) && netif_oper_up(dev)) {
 		if (p->state == BR_STATE_DISABLED)
 			br_stp_enable_port(p);
 	} else {
@@ -383,7 +383,7 @@
 	spin_lock_bh(&br->lock);
 	changed_addr = br_stp_recalculate_bridge_id(br);
 
-	if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
+	if (netif_running(dev) && netif_oper_up(dev) &&
 	    (br->dev->flags & IFF_UP))
 		br_stp_enable_port(p);
 	spin_unlock_bh(&br->lock);
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 97ba018..caa3f69 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -181,8 +181,11 @@
 	if (p->br->stp_enabled == BR_KERNEL_STP)
 		return -EBUSY;
 
+	/* if device is not up, change is not allowed
+	 * if link is not present, only allowable state is disabled
+	 */
 	if (!netif_running(p->dev) ||
-	    (!netif_carrier_ok(p->dev) && state != BR_STATE_DISABLED))
+	    (!netif_oper_up(p->dev) && state != BR_STATE_DISABLED))
 		return -ENETDOWN;
 
 	p->state = state;
diff --git a/net/bridge/br_notify.c b/net/bridge/br_notify.c
index a76b621..1644b3e 100644
--- a/net/bridge/br_notify.c
+++ b/net/bridge/br_notify.c
@@ -82,7 +82,7 @@
 		break;
 
 	case NETDEV_UP:
-		if (netif_carrier_ok(dev) && (br->dev->flags & IFF_UP)) {
+		if (netif_running(br->dev) && netif_oper_up(dev)) {
 			spin_lock_bh(&br->lock);
 			br_stp_enable_port(p);
 			spin_unlock_bh(&br->lock);
diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c
index 9d5a414..7b5197c 100644
--- a/net/bridge/br_stp_if.c
+++ b/net/bridge/br_stp_if.c
@@ -54,7 +54,7 @@
 	br_config_bpdu_generation(br);
 
 	list_for_each_entry(p, &br->port_list, list) {
-		if ((p->dev->flags & IFF_UP) && netif_carrier_ok(p->dev))
+		if (netif_running(p->dev) && netif_oper_up(p->dev))
 			br_stp_enable_port(p);
 
 	}