3 files changed, 63 insertions, 18 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 42b200fdf12e..48ad47f402ad 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1567,6 +1567,41 @@ void netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
 }
 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
 
+#ifdef CONFIG_RPS
+/**
+ *	netif_set_real_num_rx_queues - set actual number of RX queues used
+ *	@dev: Network device
+ *	@rxq: Actual number of RX queues
+ *
+ *	This must be called either with the rtnl_lock held or before
+ *	registration of the net device.  Returns 0 on success, or a
+ *	negative error code.  If called before registration, it also
+ *	sets the maximum number of queues, and always succeeds.
+ */
+int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
+{
+	int rc;
+
+	if (dev->reg_state == NETREG_REGISTERED) {
+		ASSERT_RTNL();
+
+		if (rxq > dev->num_rx_queues)
+			return -EINVAL;
+
+		rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
+						  rxq);
+		if (rc)
+			return rc;
+	} else {
+		dev->num_rx_queues = rxq;
+	}
+
+	dev->real_num_rx_queues = rxq;
+	return 0;
+}
+EXPORT_SYMBOL(netif_set_real_num_rx_queues);
+#endif
+
 static inline void __netif_reschedule(struct Qdisc *q)
 {
 	struct softnet_data *sd;
@@ -2352,10 +2387,11 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
 
 	if (skb_rx_queue_recorded(skb)) {
 		u16 index = skb_get_rx_queue(skb);
-		if (unlikely(index >= dev->num_rx_queues)) {
-			WARN_ONCE(dev->num_rx_queues > 1, "%s received packet "
-				"on queue %u, but number of RX queues is %u\n",
-				dev->name, index, dev->num_rx_queues);
+		if (unlikely(index >= dev->real_num_rx_queues)) {
+			WARN_ONCE(dev->real_num_rx_queues > 1,
+				  "%s received packet on queue %u, but number "
+				  "of RX queues is %u\n",
+				  dev->name, index, dev->real_num_rx_queues);
 			goto done;
 		}
 		rxqueue = dev->_rx + index;
@@ -5472,6 +5508,7 @@ struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name,
 
 #ifdef CONFIG_RPS
 	dev->num_rx_queues = queue_count;
+	dev->real_num_rx_queues = queue_count;
 #endif
 
 	dev->gso_max_size = GSO_MAX_SIZE;
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 76485a3f910b..fa81fd0a488f 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -742,34 +742,38 @@ static int rx_queue_add_kobject(struct net_device *net, int index)
 	return error;
 }
 
-static int rx_queue_register_kobjects(struct net_device *net)
+int
+net_rx_queue_update_kobjects(struct net_device *net, int old_num, int new_num)
 {
 	int i;
 	int error = 0;
 
-	net->queues_kset = kset_create_and_add("queues",
-	    NULL, &net->dev.kobj);
-	if (!net->queues_kset)
-		return -ENOMEM;
-	for (i = 0; i < net->num_rx_queues; i++) {
+	for (i = old_num; i < new_num; i++) {
 		error = rx_queue_add_kobject(net, i);
-		if (error)
+		if (error) {
+			new_num = old_num;
 			break;
+		}
 	}
 
-	if (error)
-		while (--i >= 0)
-			kobject_put(&net->_rx[i].kobj);
+	while (--i >= new_num)
+		kobject_put(&net->_rx[i].kobj);
 
 	return error;
 }
 
-static void rx_queue_remove_kobjects(struct net_device *net)
+static int rx_queue_register_kobjects(struct net_device *net)
 {
-	int i;
+	net->queues_kset = kset_create_and_add("queues",
+	    NULL, &net->dev.kobj);
+	if (!net->queues_kset)
+		return -ENOMEM;
+	return net_rx_queue_update_kobjects(net, 0, net->real_num_rx_queues);
+}
 
-	for (i = 0; i < net->num_rx_queues; i++)
-		kobject_put(&net->_rx[i].kobj);
+static void rx_queue_remove_kobjects(struct net_device *net)
+{
+	net_rx_queue_update_kobjects(net, net->real_num_rx_queues, 0);
 	kset_unregister(net->queues_kset);
 }
 #endif /* CONFIG_RPS */
diff --git a/net/core/net-sysfs.h b/net/core/net-sysfs.h
index 805555e8b187..778e1571548d 100644
--- a/net/core/net-sysfs.h
+++ b/net/core/net-sysfs.h
@@ -4,4 +4,8 @@
 int netdev_kobject_init(void);
 int netdev_register_kobject(struct net_device *);
 void netdev_unregister_kobject(struct net_device *);
+#ifdef CONFIG_RPS
+int net_rx_queue_update_kobjects(struct net_device *, int old_num, int new_num);
+#endif
+
 #endif