datapath: When adding a port, return the new port number to userspace.

'port' is a kernel-space copy of the odp_port and modifying it is useless.
'portp' is the userspace copy; modifying it is useful.

None of our current userspace users care about the port number and so we
never noticed.

Found by sparse (http://sparse.wiki.kernel.org/).

diff --git a/datapath/datapath.c b/datapath/datapath.c
index ba363fb..94f3196 100644 (file)
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -422,7 +422,7 @@ got_port_no:
 
        dp_sysfs_add_if(dp->ports[port_no]);
 
-       err = __put_user(port_no, &port.port);
+       err = __put_user(port_no, &portp->port);
 
 out_put:
        dev_put(dev);