ila: Create net/ipv6/ila directory

Create ila directory in preparation for supporting other hooks in the
kernel than LWT for doing ILA. This includes:
  - Moving ila.c to ila/ila_lwt.c
  - Splitting out some common functions into ila_common.c
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/Makefile

@@ -34,7 +34,7 @@ obj-$(CONFIG_INET6_XFRM_MODE_TUNNEL) += xfrm6_mode_tunnel.o
 obj-$(CONFIG_INET6_XFRM_MODE_ROUTEOPTIMIZATION) += xfrm6_mode_ro.o
 obj-$(CONFIG_INET6_XFRM_MODE_BEET) += xfrm6_mode_beet.o
 obj-$(CONFIG_IPV6_MIP6) += mip6.o
-obj-$(CONFIG_IPV6_ILA) += ila.o
+obj-$(CONFIG_IPV6_ILA) += ila/
 obj-$(CONFIG_NETFILTER)	+= netfilter/
 
 obj-$(CONFIG_IPV6_VTI) += ip6_vti.o

net/ipv6/ila/Makefile

+#
+# Makefile for ILA module
+#
+
+obj-$(CONFIG_IPV6_ILA) += ila.o
+
+ila-objs := ila_common.o ila_lwt.o

net/ipv6/ila/ila.h

+/*
+ * Copyright (c) 2015 Tom Herbert <tom@herbertland.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ */
+
+#ifndef __ILA_H
+#define __ILA_H
+
+#include <linux/errno.h>
+#include <linux/ip.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/socket.h>
+#include <linux/skbuff.h>
+#include <linux/types.h>
+#include <net/checksum.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <uapi/linux/ila.h>
+
+struct ila_params {
+	__be64 locator;
+	__be64 locator_match;
+	__wsum csum_diff;
+};
+
+static inline __wsum compute_csum_diff8(const __be32 *from, const __be32 *to)
+{
+	__be32 diff[] = {
+		~from[0], ~from[1], to[0], to[1],
+	};
+
+	return csum_partial(diff, sizeof(diff), 0);
+}
+
+void update_ipv6_locator(struct sk_buff *skb, struct ila_params *p);
+
+int ila_lwt_init(void);
+void ila_lwt_fini(void);
+
+#endif /* __ILA_H */

net/ipv6/ila/ila_common.c

+#include <linux/errno.h>
+#include <linux/ip.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/socket.h>
+#include <linux/types.h>
+#include <net/checksum.h>
+#include <net/ip.h>
+#include <net/ip6_fib.h>
+#include <net/lwtunnel.h>
+#include <net/protocol.h>
+#include <uapi/linux/ila.h>
+#include "ila.h"
+
+static __wsum get_csum_diff(struct ipv6hdr *ip6h, struct ila_params *p)
+{
+	if (*(__be64 *)&ip6h->daddr == p->locator_match)
+		return p->csum_diff;
+	else
+		return compute_csum_diff8((__be32 *)&ip6h->daddr,
+					  (__be32 *)&p->locator);
+}
+
+void update_ipv6_locator(struct sk_buff *skb, struct ila_params *p)
+{
+	__wsum diff;
+	struct ipv6hdr *ip6h = ipv6_hdr(skb);
+	size_t nhoff = sizeof(struct ipv6hdr);
+
+	/* First update checksum */
+	switch (ip6h->nexthdr) {
+	case NEXTHDR_TCP:
+		if (likely(pskb_may_pull(skb, nhoff + sizeof(struct tcphdr)))) {
+			struct tcphdr *th = (struct tcphdr *)
+					(skb_network_header(skb) + nhoff);
+
+			diff = get_csum_diff(ip6h, p);
+			inet_proto_csum_replace_by_diff(&th->check, skb,
+							diff, true);
+		}
+		break;
+	case NEXTHDR_UDP:
+		if (likely(pskb_may_pull(skb, nhoff + sizeof(struct udphdr)))) {
+			struct udphdr *uh = (struct udphdr *)
+					(skb_network_header(skb) + nhoff);
+
+			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
+				diff = get_csum_diff(ip6h, p);
+				inet_proto_csum_replace_by_diff(&uh->check, skb,
+								diff, true);
+				if (!uh->check)
+					uh->check = CSUM_MANGLED_0;
+			}
+		}
+		break;
+	case NEXTHDR_ICMP:
+		if (likely(pskb_may_pull(skb,
+					 nhoff + sizeof(struct icmp6hdr)))) {
+			struct icmp6hdr *ih = (struct icmp6hdr *)
+					(skb_network_header(skb) + nhoff);
+
+			diff = get_csum_diff(ip6h, p);
+			inet_proto_csum_replace_by_diff(&ih->icmp6_cksum, skb,
+							diff, true);
+		}
+		break;
+	}
+
+	/* Now change destination address */
+	*(__be64 *)&ip6h->daddr = p->locator;
+}
+
+static int __init ila_init(void)
+{
+	int ret;
+
+	ret = ila_lwt_init();
+
+	if (ret)
+		goto fail_lwt;
+
+fail_lwt:
+	return ret;
+}
+
+static void __exit ila_fini(void)
+{
+	ila_lwt_fini();
+}
+
+module_init(ila_init);
+module_exit(ila_fini);
+MODULE_AUTHOR("Tom Herbert <tom@herbertland.com>");
+MODULE_LICENSE("GPL");

net/ipv6/ila.c → net/ipv6/ila/ila_lwt.c

@@ -11,12 +11,7 @@
 #include <net/lwtunnel.h>
 #include <net/protocol.h>
 #include <uapi/linux/ila.h>
-
-struct ila_params {
-	__be64 locator;
-	__be64 locator_match;
-	__wsum csum_diff;
-};
+#include "ila.h"
 
 static inline struct ila_params *ila_params_lwtunnel(
 	struct lwtunnel_state *lwstate)
@@ -24,73 +19,6 @@ static inline struct ila_params *ila_params_lwtunnel(
 	return (struct ila_params *)lwstate->data;
 }
 
-static inline __wsum compute_csum_diff8(const __be32 *from, const __be32 *to)
-{
-	__be32 diff[] = {
-		~from[0], ~from[1], to[0], to[1],
-	};
-
-	return csum_partial(diff, sizeof(diff), 0);
-}
-
-static inline __wsum get_csum_diff(struct ipv6hdr *ip6h, struct ila_params *p)
-{
-	if (*(__be64 *)&ip6h->daddr == p->locator_match)
-		return p->csum_diff;
-	else
-		return compute_csum_diff8((__be32 *)&ip6h->daddr,
-					  (__be32 *)&p->locator);
-}
-
-static void update_ipv6_locator(struct sk_buff *skb, struct ila_params *p)
-{
-	__wsum diff;
-	struct ipv6hdr *ip6h = ipv6_hdr(skb);
-	size_t nhoff = sizeof(struct ipv6hdr);
-
-	/* First update checksum */
-	switch (ip6h->nexthdr) {
-	case NEXTHDR_TCP:
-		if (likely(pskb_may_pull(skb, nhoff + sizeof(struct tcphdr)))) {
-			struct tcphdr *th = (struct tcphdr *)
-					(skb_network_header(skb) + nhoff);
-
-			diff = get_csum_diff(ip6h, p);
-			inet_proto_csum_replace_by_diff(&th->check, skb,
-							diff, true);
-		}
-		break;
-	case NEXTHDR_UDP:
-		if (likely(pskb_may_pull(skb, nhoff + sizeof(struct udphdr)))) {
-			struct udphdr *uh = (struct udphdr *)
-					(skb_network_header(skb) + nhoff);
-
-			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
-				diff = get_csum_diff(ip6h, p);
-				inet_proto_csum_replace_by_diff(&uh->check, skb,
-								diff, true);
-				if (!uh->check)
-					uh->check = CSUM_MANGLED_0;
-			}
-		}
-		break;
-	case NEXTHDR_ICMP:
-		if (likely(pskb_may_pull(skb,
-					 nhoff + sizeof(struct icmp6hdr)))) {
-			struct icmp6hdr *ih = (struct icmp6hdr *)
-					(skb_network_header(skb) + nhoff);
-
-			diff = get_csum_diff(ip6h, p);
-			inet_proto_csum_replace_by_diff(&ih->icmp6_cksum, skb,
-							diff, true);
-		}
-		break;
-	}
-
-	/* Now change destination address */
-	*(__be64 *)&ip6h->daddr = p->locator;
-}
-
 static int ila_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
@@ -213,17 +141,12 @@ static const struct lwtunnel_encap_ops ila_encap_ops = {
 	.cmp_encap = ila_encap_cmp,
 };
 
-static int __init ila_init(void)
+int ila_lwt_init(void)
 {
 	return lwtunnel_encap_add_ops(&ila_encap_ops, LWTUNNEL_ENCAP_ILA);
 }
 
-static void __exit ila_fini(void)
+void ila_lwt_fini(void)
 {
 	lwtunnel_encap_del_ops(&ila_encap_ops, LWTUNNEL_ENCAP_ILA);
 }
-
-module_init(ila_init);
-module_exit(ila_fini);
-MODULE_AUTHOR("Tom Herbert <tom@herbertland.com>");
-MODULE_LICENSE("GPL");