net: Add queue state xoff flag for stack

Create separate queue state flags so that either the stack or drivers
can turn on XOFF.  Added a set of functions used in the stack to determine
if a queue is really stopped (either by stack or driver)

Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 79ac145..67fc573 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -60,7 +60,7 @@
 
 		/* check the reason of requeuing without tx lock first */
 		txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
-		if (!netif_tx_queue_frozen_or_stopped(txq)) {
+		if (!netif_xmit_frozen_or_stopped(txq)) {
 			q->gso_skb = NULL;
 			q->q.qlen--;
 		} else
@@ -121,7 +121,7 @@
 	spin_unlock(root_lock);
 
 	HARD_TX_LOCK(dev, txq, smp_processor_id());
-	if (!netif_tx_queue_frozen_or_stopped(txq))
+	if (!netif_xmit_frozen_or_stopped(txq))
 		ret = dev_hard_start_xmit(skb, dev, txq);
 
 	HARD_TX_UNLOCK(dev, txq);
@@ -143,7 +143,7 @@
 		ret = dev_requeue_skb(skb, q);
 	}
 
-	if (ret && netif_tx_queue_frozen_or_stopped(txq))
+	if (ret && netif_xmit_frozen_or_stopped(txq))
 		ret = 0;
 
 	return ret;
@@ -242,7 +242,7 @@
 				 * old device drivers set dev->trans_start
 				 */
 				trans_start = txq->trans_start ? : dev->trans_start;
-				if (netif_tx_queue_stopped(txq) &&
+				if (netif_xmit_stopped(txq) &&
 				    time_after(jiffies, (trans_start +
 							 dev->watchdog_timeo))) {
 					some_queue_timedout = 1;