net/smc: add pnet table namespace support

This patch adds namespace support to the pnet table code. Each network
namespace gets its own pnet table. Infiniband and smcd device pnetids
can only be modified in the initial namespace. In other namespaces they
can still be used as if they were set by the underlying hardware.

Signed-off-by: Hans Wippel <hwippel@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/smc/af_smc.c

@@ -30,6 +30,10 @@
 #include <net/smc.h>
 #include <asm/ioctls.h>
 
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+#include "smc_netns.h"
+
 #include "smc.h"
 #include "smc_clc.h"
 #include "smc_llc.h"
@@ -1966,10 +1970,33 @@ static const struct net_proto_family smc_sock_family_ops = {
 	.create	= smc_create,
 };
 
+unsigned int smc_net_id;
+
+static __net_init int smc_net_init(struct net *net)
+{
+	return smc_pnet_net_init(net);
+}
+
+static void __net_exit smc_net_exit(struct net *net)
+{
+	smc_pnet_net_exit(net);
+}
+
+static struct pernet_operations smc_net_ops = {
+	.init = smc_net_init,
+	.exit = smc_net_exit,
+	.id   = &smc_net_id,
+	.size = sizeof(struct smc_net),
+};
+
 static int __init smc_init(void)
 {
 	int rc;
 
+	rc = register_pernet_subsys(&smc_net_ops);
+	if (rc)
+		return rc;
+
 	rc = smc_pnet_init();
 	if (rc)
 		return rc;
@@ -2035,6 +2062,7 @@ static void __exit smc_exit(void)
 	proto_unregister(&smc_proto6);
 	proto_unregister(&smc_proto);
 	smc_pnet_exit();
+	unregister_pernet_subsys(&smc_net_ops);
 }
 
 module_init(smc_init);

net/smc/smc_netns.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Shared Memory Communications
+ *
+ * Network namespace definitions.
+ *
+ * Copyright IBM Corp. 2018
+ */
+
+#ifndef SMC_NETNS_H
+#define SMC_NETNS_H
+
+#include "smc_pnet.h"
+
+extern unsigned int smc_net_id;
+
+/* per-network namespace private data */
+struct smc_net {
+	struct smc_pnettable pnettable;
+};
+#endif