hv_netvsc: Split netvsc_revoke_buf() and netvsc_teardown_gpadl()

Split each of the functions into two for each of send/recv buffers.
This will be needed in order to implement a fine-grained messaging
sequence to the host so that we accommodate the requirements of
different Windows versions

Fixes: 0ef58b0a ("hv_netvsc: change GPAD teardown order on older versions")
Signed-off-by: Mohammed Gamal <mgamal@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/hyperv/netvsc.c

@@ -109,11 +109,11 @@ static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
 	call_rcu(&nvdev->rcu, free_netvsc_device);
 }
 
-static void netvsc_revoke_buf(struct hv_device *device,
+static void netvsc_revoke_recv_buf(struct hv_device *device,
 				   struct netvsc_device *net_device)
 {
-	struct nvsp_message *revoke_packet;
 	struct net_device *ndev = hv_get_drvdata(device);
+	struct nvsp_message *revoke_packet;
 	int ret;
 
 	/*
@@ -157,6 +157,14 @@ static void netvsc_revoke_buf(struct hv_device *device,
 		}
 		net_device->recv_section_cnt = 0;
 	}
+}
+
+static void netvsc_revoke_send_buf(struct hv_device *device,
+				   struct netvsc_device *net_device)
+{
+	struct net_device *ndev = hv_get_drvdata(device);
+	struct nvsp_message *revoke_packet;
+	int ret;
 
 	/* Deal with the send buffer we may have setup.
 	 * If we got a  send section size, it means we received a
@@ -202,7 +210,7 @@ static void netvsc_revoke_buf(struct hv_device *device,
 	}
 }
 
-static void netvsc_teardown_gpadl(struct hv_device *device,
+static void netvsc_teardown_recv_gpadl(struct hv_device *device,
 				       struct netvsc_device *net_device)
 {
 	struct net_device *ndev = hv_get_drvdata(device);
@@ -222,6 +230,13 @@ static void netvsc_teardown_gpadl(struct hv_device *device,
 		}
 		net_device->recv_buf_gpadl_handle = 0;
 	}
+}
+
+static void netvsc_teardown_send_gpadl(struct hv_device *device,
+				       struct netvsc_device *net_device)
+{
+	struct net_device *ndev = hv_get_drvdata(device);
+	int ret;
 
 	if (net_device->send_buf_gpadl_handle) {
 		ret = vmbus_teardown_gpadl(device->channel,
@@ -437,8 +452,10 @@ static int netvsc_init_buf(struct hv_device *device,
 	goto exit;
 
 cleanup:
-	netvsc_revoke_buf(device, net_device);
-	netvsc_teardown_gpadl(device, net_device);
+	netvsc_revoke_recv_buf(device, net_device);
+	netvsc_revoke_send_buf(device, net_device);
+	netvsc_teardown_recv_gpadl(device, net_device);
+	netvsc_teardown_send_gpadl(device, net_device);
 
 exit:
 	return ret;
@@ -575,7 +592,8 @@ void netvsc_device_remove(struct hv_device *device)
 		= rtnl_dereference(net_device_ctx->nvdev);
 	int i;
 
-	netvsc_revoke_buf(device, net_device);
+	netvsc_revoke_recv_buf(device, net_device);
+	netvsc_revoke_send_buf(device, net_device);
 
 	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
 
@@ -590,14 +608,18 @@ void netvsc_device_remove(struct hv_device *device)
 	netdev_dbg(ndev, "net device safe to remove\n");
 
 	/* older versions require that buffer be revoked before close */
-	if (vmbus_proto_version < VERSION_WIN10)
-		netvsc_teardown_gpadl(device, net_device);
+	if (vmbus_proto_version < VERSION_WIN10) {
+		netvsc_teardown_recv_gpadl(device, net_device);
+		netvsc_teardown_send_gpadl(device, net_device);
+	}
 
 	/* Now, we can close the channel safely */
 	vmbus_close(device->channel);
 
-	if (vmbus_proto_version >= VERSION_WIN10)
-		netvsc_teardown_gpadl(device, net_device);
+	if (vmbus_proto_version >= VERSION_WIN10) {
+		netvsc_teardown_recv_gpadl(device, net_device);
+		netvsc_teardown_send_gpadl(device, net_device);
+	}
 
 	/* Release all resources */
 	free_netvsc_device_rcu(net_device);