SUNRPC: Bury "#ifdef IPV6" in svc_create_xprt()

Clean up:  Bruce observed we have more or less common logic in each of
svc_create_xprt()'s callers:  the check to create an IPv6 RPC listener
socket only if CONFIG_IPV6 is set.  I'm about to add another case
that does just the same.

If we move the ifdefs into __svc_xpo_create(), then svc_create_xprt()
call sites can get rid of the "#ifdef" ugliness, and can use the same
logic with or without IPv6 support available in the kernel.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

fs/lockd/svc.c

@@ -243,11 +243,9 @@ static int make_socks(struct svc_serv *serv)
 	if (err < 0)
 		goto out_err;
 
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 	err = create_lockd_family(serv, PF_INET6);
 	if (err < 0 && err != -EAFNOSUPPORT)
 		goto out_err;
-#endif	/* CONFIG_IPV6 || CONFIG_IPV6_MODULE */
 
 	warned = 0;
 	return 0;

fs/nfs/callback.c

@@ -118,7 +118,6 @@ nfs4_callback_up(struct svc_serv *serv)
 	dprintk("NFS: Callback listener port = %u (af %u)\n",
 			nfs_callback_tcpport, PF_INET);
 
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 	ret = svc_create_xprt(serv, "tcp", PF_INET6,
 				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
 	if (ret > 0) {
@@ -129,7 +128,6 @@ nfs4_callback_up(struct svc_serv *serv)
 		ret = 0;
 	else
 		goto out_err;
-#endif	/* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 
 	return svc_prepare_thread(serv, &serv->sv_pools[0]);
 

net/sunrpc/svc_xprt.c

@@ -173,11 +173,13 @@ static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl,
 		.sin_addr.s_addr	= htonl(INADDR_ANY),
 		.sin_port		= htons(port),
 	};
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 	struct sockaddr_in6 sin6 = {
 		.sin6_family		= AF_INET6,
 		.sin6_addr		= IN6ADDR_ANY_INIT,
 		.sin6_port		= htons(port),
 	};
+#endif	/* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 	struct sockaddr *sap;
 	size_t len;
 
@@ -186,10 +188,12 @@ static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl,
 		sap = (struct sockaddr *)&sin;
 		len = sizeof(sin);
 		break;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 	case PF_INET6:
 		sap = (struct sockaddr *)&sin6;
 		len = sizeof(sin6);
 		break;
+#endif	/* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 	default:
 		return ERR_PTR(-EAFNOSUPPORT);
 	}