netvsc: need rcu_derefence when accessing internal device info

The netvsc_device structure should be accessed by rcu_dereference
in the send path.  Change arguments to netvsc_send() to make
this easier to do correctly.

Remove no longer needed hv_device_to_netvsc_device.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index e620374..0054b69 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -183,10 +183,12 @@ struct rndis_device {
 /* Interface */
 struct rndis_message;
 struct netvsc_device;
+struct net_device_context;
+
 struct netvsc_device *netvsc_device_add(struct hv_device *device,
 					const struct netvsc_device_info *info);
 void netvsc_device_remove(struct hv_device *device);
-int netvsc_send(struct hv_device *device,
+int netvsc_send(struct net_device_context *ndc,
 		struct hv_netvsc_packet *packet,
 		struct rndis_message *rndis_msg,
 		struct hv_page_buffer **page_buffer,
@@ -790,12 +792,6 @@ net_device_to_netvsc_device(struct net_device *ndev)
 	return ((struct net_device_context *)netdev_priv(ndev))->nvdev;
 }
 
-static inline struct netvsc_device *
-hv_device_to_netvsc_device(struct hv_device *device)
-{
-	return net_device_to_netvsc_device(hv_get_drvdata(device));
-}
-
 /* NdisInitialize message */
 struct rndis_initialize_request {
 	u32 req_id;