net: implement dev_disable_lro() hw_features compatibility

Implement compatibility with new hw_features for dev_disable_lro().
This is a transition path - dev_disable_lro() should be later
integrated into netdev_fix_features() after all drivers are converted.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/ethtool.h

@@ -648,6 +648,9 @@ enum ethtool_sfeatures_retval_bits {
 
 #include <linux/rculist.h>
 
+/* needed by dev_disable_lro() */
+extern int __ethtool_set_flags(struct net_device *dev, u32 flags);
+
 struct ethtool_rx_ntuple_flow_spec_container {
 	struct ethtool_rx_ntuple_flow_spec fs;
 	struct list_head list;

net/core/dev.c

@@ -1353,14 +1353,17 @@ EXPORT_SYMBOL(dev_close);
  */
 void dev_disable_lro(struct net_device *dev)
 {
-	if (dev->ethtool_ops && dev->ethtool_ops->get_flags &&
-	    dev->ethtool_ops->set_flags) {
-		u32 flags = dev->ethtool_ops->get_flags(dev);
-		if (flags & ETH_FLAG_LRO) {
-			flags &= ~ETH_FLAG_LRO;
-			dev->ethtool_ops->set_flags(dev, flags);
-		}
-	}
+	u32 flags;
+
+	if (dev->ethtool_ops && dev->ethtool_ops->get_flags)
+		flags = dev->ethtool_ops->get_flags(dev);
+	else
+		flags = ethtool_op_get_flags(dev);
+
+	if (!(flags & ETH_FLAG_LRO))
+		return;
+
+	__ethtool_set_flags(dev, flags & ~ETH_FLAG_LRO);
 	WARN_ON(dev->features & NETIF_F_LRO);
 }
 EXPORT_SYMBOL(dev_disable_lro);

net/core/ethtool.c

@@ -513,7 +513,7 @@ static int ethtool_set_one_feature(struct net_device *dev,
 	}
 }
 
-static int __ethtool_set_flags(struct net_device *dev, u32 data)
+int __ethtool_set_flags(struct net_device *dev, u32 data)
 {
 	u32 changed;