hv_netvsc: pass struct netvsc_device to rndis_filter_{open, close}()

BugLink: http://bugs.launchpad.net/bugs/1616677

Both rndis_filter_open()/rndis_filter_close() use struct hv_device to
reach to struct netvsc_device only and all callers have it already.
While on it, rename net_device to nvdev in rndis_filter_open() as
net_device is misleading.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 2f5fa6c8)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>
Acked-by: Kamal Mostafa <kamal@canonical.com>

drivers/net/hyperv/hyperv_net.h

@@ -173,6 +173,7 @@ struct rndis_device {
 
 /* Interface */
 struct rndis_message;
+struct netvsc_device;
 int netvsc_device_add(struct hv_device *device, void *additional_info);
 int netvsc_device_remove(struct hv_device *device);
 int netvsc_send(struct hv_device *device,
@@ -189,8 +190,8 @@ int netvsc_recv_callback(struct hv_device *device_obj,
 			struct vmbus_channel *channel,
 			u16 vlan_tci);
 void netvsc_channel_cb(void *context);
-int rndis_filter_open(struct hv_device *dev);
-int rndis_filter_close(struct hv_device *dev);
+int rndis_filter_open(struct netvsc_device *nvdev);
+int rndis_filter_close(struct netvsc_device *nvdev);
 int rndis_filter_device_add(struct hv_device *dev,
 			void *additional_info);
 void rndis_filter_device_remove(struct hv_device *dev);

drivers/net/hyperv/netvsc_drv.c

@@ -98,16 +98,14 @@ static void netvsc_set_multicast_list(struct net_device *net)
 
 static int netvsc_open(struct net_device *net)
 {
-	struct net_device_context *net_device_ctx = netdev_priv(net);
-	struct hv_device *device_obj = net_device_ctx->device_ctx;
-	struct netvsc_device *nvdev = net_device_ctx->nvdev;
+	struct netvsc_device *nvdev = net_device_to_netvsc_device(net);
 	struct rndis_device *rdev;
 	int ret = 0;
 
 	netif_carrier_off(net);
 
 	/* Open up the device */
-	ret = rndis_filter_open(device_obj);
+	ret = rndis_filter_open(nvdev);
 	if (ret != 0) {
 		netdev_err(net, "unable to open device (ret %d).\n", ret);
 		return ret;
@@ -125,7 +123,6 @@ static int netvsc_open(struct net_device *net)
 static int netvsc_close(struct net_device *net)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(net);
-	struct hv_device *device_obj = net_device_ctx->device_ctx;
 	struct netvsc_device *nvdev = net_device_ctx->nvdev;
 	int ret;
 	u32 aread, awrite, i, msec = 10, retry = 0, retry_max = 20;
@@ -135,7 +132,7 @@ static int netvsc_close(struct net_device *net)
 
 	/* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
 	cancel_work_sync(&net_device_ctx->work);
-	ret = rndis_filter_close(device_obj);
+	ret = rndis_filter_close(nvdev);
 	if (ret != 0) {
 		netdev_err(net, "unable to close device (ret %d).\n", ret);
 		return ret;
@@ -1247,7 +1244,7 @@ static int netvsc_vf_up(struct net_device *vf_netdev)
 	/*
 	 * Open the device before switching data path.
 	 */
-	rndis_filter_open(net_device_ctx->device_ctx);
+	rndis_filter_open(netvsc_dev);
 
 	/*
 	 * notify the host to switch the data path.
@@ -1302,7 +1299,7 @@ static int netvsc_vf_down(struct net_device *vf_netdev)
 		udelay(50);
 	netvsc_switch_datapath(ndev, false);
 	netdev_info(ndev, "Data path switched from VF: %s\n", vf_netdev->name);
-	rndis_filter_close(net_device_ctx->device_ctx);
+	rndis_filter_close(netvsc_dev);
 	netif_carrier_on(ndev);
 	/*
 	 * Notify peers.

drivers/net/hyperv/rndis_filter.c

@@ -1216,23 +1216,19 @@ void rndis_filter_device_remove(struct hv_device *dev)
 }
 
 
-int rndis_filter_open(struct hv_device *dev)
+int rndis_filter_open(struct netvsc_device *nvdev)
 {
-	struct netvsc_device *net_device = hv_device_to_netvsc_device(dev);
-
-	if (!net_device)
+	if (!nvdev)
 		return -EINVAL;
 
-	if (atomic_inc_return(&net_device->open_cnt) != 1)
+	if (atomic_inc_return(&nvdev->open_cnt) != 1)
 		return 0;
 
-	return rndis_filter_open_device(net_device->extension);
+	return rndis_filter_open_device(nvdev->extension);
 }
 
-int rndis_filter_close(struct hv_device *dev)
+int rndis_filter_close(struct netvsc_device *nvdev)
 {
-	struct netvsc_device *nvdev = hv_device_to_netvsc_device(dev);
-
 	if (!nvdev)
 		return -EINVAL;