sunrpc: add netns inum and srcaddr to debugfs rpc_xprt info

The output format should provide a value that matches the one in
the /proc/<pid>/ns/net symlink. This makes it simpler to match the
rpc_xprt and rpc_clnt to a particular container.

Also, when the xprt defines the get_srcaddr operation, use that to
display the source address as well.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>

net/sunrpc/debugfs.c

@@ -182,6 +182,18 @@ xprt_info_show(struct seq_file *f, void *v)
 	seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
 	seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
 	seq_printf(f, "state: 0x%lx\n", xprt->state);
+	seq_printf(f, "netns: %u\n", xprt->xprt_net->ns.inum);
+
+	if (xprt->ops->get_srcaddr) {
+		int ret, buflen;
+		char buf[INET6_ADDRSTRLEN];
+
+		buflen = ARRAY_SIZE(buf);
+		ret = xprt->ops->get_srcaddr(xprt, buf, buflen);
+		if (ret < 0)
+			ret = sprintf(buf, "<closed>");
+		seq_printf(f, "saddr: %.*s\n", ret, buf);
+	}
 	return 0;
 }