1 files changed, 30 insertions, 46 deletions

diff --git a/net/ipv6/protocol.c b/net/ipv6/protocol.c
index f929f47b925..e048cf1bb6a 100644
--- a/net/ipv6/protocol.c
+++ b/net/ipv6/protocol.c
@@ -5,8 +5,6 @@
  *
  *		PF_INET6 protocol dispatch tables.
  *
- * Version:	$Id: protocol.c,v 1.10 2001/05/18 02:25:49 davem Exp $
- *
  * Authors:	Pedro Roque	<roque@di.fc.ul.pt>
  *
  *		This program is free software; you can redistribute it and/or
@@ -22,68 +20,54 @@
  *      - Removed unused variable 'inet6_protocol_base'
  *      - Modified inet6_del_protocol() to correctly maintain copy bit.
  */
-
-#include <linux/errno.h>
-#include <linux/types.h>
-#include <linux/socket.h>
-#include <linux/sockios.h>
-#include <linux/net.h>
-#include <linux/in6.h>
+#include <linux/module.h>
 #include <linux/netdevice.h>
-#include <linux/if_arp.h>
-
-#include <net/sock.h>
-#include <net/snmp.h>
-
-#include <net/ipv6.h>
+#include <linux/spinlock.h>
 #include <net/protocol.h>
 
-struct inet6_protocol *inet6_protos[MAX_INET_PROTOS];
-static DEFINE_SPINLOCK(inet6_proto_lock);
-
+#if IS_ENABLED(CONFIG_IPV6)
+const struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS] __read_mostly;
+EXPORT_SYMBOL(inet6_protos);
 
-int inet6_add_protocol(struct inet6_protocol *prot, unsigned char protocol)
+int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char protocol)
 {
-	int ret, hash = protocol & (MAX_INET_PROTOS - 1);
+	return !cmpxchg((const struct inet6_protocol **)&inet6_protos[protocol],
+			NULL, prot) ? 0 : -1;
+}
+EXPORT_SYMBOL(inet6_add_protocol);
 
-	spin_lock_bh(&inet6_proto_lock);
+int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char protocol)
+{
+	int ret;
 
-	if (inet6_protos[hash]) {
-		ret = -1;
-	} else {
-		inet6_protos[hash] = prot;
-		ret = 0;
-	}
+	ret = (cmpxchg((const struct inet6_protocol **)&inet6_protos[protocol],
+		       prot, NULL) == prot) ? 0 : -1;
 
-	spin_unlock_bh(&inet6_proto_lock);
+	synchronize_net();
 
 	return ret;
 }
+EXPORT_SYMBOL(inet6_del_protocol);
+#endif
 
-EXPORT_SYMBOL(inet6_add_protocol);
-
-/*
- *	Remove a protocol from the hash tables.
- */
+const struct net_offload __rcu *inet6_offloads[MAX_INET_PROTOS] __read_mostly;
 
-int inet6_del_protocol(struct inet6_protocol *prot, unsigned char protocol)
+int inet6_add_offload(const struct net_offload *prot, unsigned char protocol)
 {
-	int ret, hash = protocol & (MAX_INET_PROTOS - 1);
-
-	spin_lock_bh(&inet6_proto_lock);
+	return !cmpxchg((const struct net_offload **)&inet6_offloads[protocol],
+			NULL, prot) ? 0 : -1;
+}
+EXPORT_SYMBOL(inet6_add_offload);
 
-	if (inet6_protos[hash] != prot) {
-		ret = -1;
-	} else {
-		inet6_protos[hash] = NULL;
-		ret = 0;
-	}
+int inet6_del_offload(const struct net_offload *prot, unsigned char protocol)
+{
+	int ret;
 
-	spin_unlock_bh(&inet6_proto_lock);
+	ret = (cmpxchg((const struct net_offload **)&inet6_offloads[protocol],
+		       prot, NULL) == prot) ? 0 : -1;
 
 	synchronize_net();
 
 	return ret;
 }
-
-EXPORT_SYMBOL(inet6_del_protocol);
+EXPORT_SYMBOL(inet6_del_offload);