SUNRPC query transport's source port

Provide ability to query transport's source port.
Signed-off-by: NOlga Kornievskaia <kolga@netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

include/linux/sunrpc/xprtsock.h

@@ -10,6 +10,7 @@
 
 int		init_socket_xprt(void);
 void		cleanup_socket_xprt(void);
+unsigned short	get_srcport(struct rpc_xprt *);
 
 #define RPC_MIN_RESVPORT	(1U)
 #define RPC_MAX_RESVPORT	(65535U)

net/sunrpc/xprtsock.c

@@ -1653,6 +1653,13 @@ static int xs_get_srcport(struct sock_xprt *transport)
 	return port;
 }
 
+unsigned short get_srcport(struct rpc_xprt *xprt)
+{
+	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
+	return sock->srcport;
+}
+EXPORT_SYMBOL(get_srcport);
+
 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
 {
 	if (transport->srcport != 0)