compat: Remove duplicate metadata destination code

ip_gre.c and ip6_gre.c both had duplicate code for handling the tunnel
metadata destinations.  Move the duplicate code over into the right
header file, dst_metadata.h.

Signed-off-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

3 files changed, 133 insertions, 183 deletions

diff --git a/datapath/linux/compat/include/net/dst_metadata.h b/datapath/linux/compat/include/net/dst_metadata.h
index 9a82b3ce1..4ffafccce 100644
--- a/datapath/linux/compat/include/net/dst_metadata.h
+++ b/datapath/linux/compat/include/net/dst_metadata.h
@@ -30,6 +30,137 @@ struct metadata_dst {
 	} u;
 };
 
+#ifndef DST_METADATA
+#define DST_METADATA 0x0080
+#endif
+
+extern struct dst_ops md_dst_ops;
+
+static void rpl__metadata_dst_init(struct metadata_dst *md_dst,
+				enum metadata_type type, u8 optslen)
+
+{
+	struct dst_entry *dst;
+
+	dst = &md_dst->dst;
+	dst_init(dst, &md_dst_ops, NULL, 1, DST_OBSOLETE_NONE,
+		 DST_METADATA | DST_NOCOUNT);
+
+#if 0
+	/* unused in OVS */
+	dst->input = dst_md_discard;
+	dst->output = dst_md_discard_out;
+#endif
+	memset(dst + 1, 0, sizeof(*md_dst) + optslen - sizeof(*dst));
+	md_dst->type = type;
+}
+
+static struct
+metadata_dst *__rpl_metadata_dst_alloc(u8 optslen,
+				       enum metadata_type type,
+				       gfp_t flags)
+{
+	struct metadata_dst *md_dst;
+
+	md_dst = kmalloc(sizeof(*md_dst) + optslen, flags);
+	if (!md_dst)
+		return NULL;
+
+	rpl__metadata_dst_init(md_dst, type, optslen);
+
+	return md_dst;
+}
+static inline struct metadata_dst *rpl_tun_rx_dst(int md_size)
+{
+	struct metadata_dst *tun_dst;
+
+	tun_dst = __rpl_metadata_dst_alloc(md_size, METADATA_IP_TUNNEL,
+					 GFP_ATOMIC);
+	if (!tun_dst)
+		return NULL;
+
+	tun_dst->u.tun_info.options_len = 0;
+	tun_dst->u.tun_info.mode = 0;
+	return tun_dst;
+}
+static inline struct metadata_dst *rpl__ip_tun_set_dst(__be32 saddr,
+						    __be32 daddr,
+						    __u8 tos, __u8 ttl,
+						    __be16 tp_dst,
+						    __be16 flags,
+						    __be64 tunnel_id,
+						    int md_size)
+{
+	struct metadata_dst *tun_dst;
+
+	tun_dst = rpl_tun_rx_dst(md_size);
+	if (!tun_dst)
+		return NULL;
+
+	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
+			   saddr, daddr, tos, ttl,
+			   0, 0, tp_dst, tunnel_id, flags);
+	return tun_dst;
+}
+
+static inline struct metadata_dst *rpl_ip_tun_rx_dst(struct sk_buff *skb,
+						 __be16 flags,
+						 __be64 tunnel_id,
+						 int md_size)
+{
+	const struct iphdr *iph = ip_hdr(skb);
+
+	return rpl__ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
+				0, flags, tunnel_id, md_size);
+}
+
+static inline
+struct metadata_dst *rpl__ipv6_tun_set_dst(const struct in6_addr *saddr,
+					   const struct in6_addr *daddr,
+					    __u8 tos, __u8 ttl,
+					    __be16 tp_dst,
+					    __be32 label,
+					    __be16 flags,
+					    __be64 tunnel_id,
+					    int md_size)
+{
+	struct metadata_dst *tun_dst;
+	struct ip_tunnel_info *info;
+
+	tun_dst = rpl_tun_rx_dst(md_size);
+	if (!tun_dst)
+		return NULL;
+
+	info = &tun_dst->u.tun_info;
+	info->mode = IP_TUNNEL_INFO_IPV6;
+	info->key.tun_flags = flags;
+	info->key.tun_id = tunnel_id;
+	info->key.tp_src = 0;
+	info->key.tp_dst = tp_dst;
+
+	info->key.u.ipv6.src = *saddr;
+	info->key.u.ipv6.dst = *daddr;
+
+	info->key.tos = tos;
+	info->key.ttl = ttl;
+	info->key.label = label;
+
+	return tun_dst;
+}
+
+static inline struct metadata_dst *rpl_ipv6_tun_rx_dst(struct sk_buff *skb,
+						 __be16 flags,
+						 __be64 tunnel_id,
+						 int md_size)
+{
+	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
+
+	return rpl__ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
+				     ipv6_get_dsfield(ip6h), ip6h->hop_limit,
+				     0, ip6_flowlabel(ip6h), flags, tunnel_id,
+				     md_size);
+}
+
 static void __metadata_dst_init(struct metadata_dst *md_dst, u8 optslen)
 {
 	struct dst_entry *dst;
@@ -127,10 +258,6 @@ rpl_metadata_dst_alloc(u8 optslen, enum metadata_type type, gfp_t flags)
 }
 #define metadata_dst_alloc rpl_metadata_dst_alloc
 
-#ifndef DST_METADATA 
-#define DST_METADATA		0x0200
-#endif
-
 static inline bool rpl_skb_valid_dst(const struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
diff --git a/datapath/linux/compat/ip6_gre.c b/datapath/linux/compat/ip6_gre.c
index ca4e66133..850e7032d 100644
--- a/datapath/linux/compat/ip6_gre.c
+++ b/datapath/linux/compat/ip6_gre.c
@@ -520,105 +520,6 @@ static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 #endif
 }
 
-static struct dst_ops md_dst_ops = {
-	.family =		AF_UNSPEC,
-};
-
-#ifndef DST_METADATA
-#define DST_METADATA 0x0080
-#endif
-
-static void rpl__metadata_dst_init(struct metadata_dst *md_dst,
-				enum metadata_type type, u8 optslen)
-
-{
-	struct dst_entry *dst;
-
-	dst = &md_dst->dst;
-	dst_init(dst, &md_dst_ops, NULL, 1, DST_OBSOLETE_NONE,
-		 DST_METADATA | DST_NOCOUNT);
-
-#if 0
-	/* unused in OVS */
-	dst->input = dst_md_discard;
-	dst->output = dst_md_discard_out;
-#endif
-	memset(dst + 1, 0, sizeof(*md_dst) + optslen - sizeof(*dst));
-	md_dst->type = type;
-}
-
-static struct metadata_dst *erspan_rpl_metadata_dst_alloc(u8 optslen, enum metadata_type type,
-					gfp_t flags)
-{
-	struct metadata_dst *md_dst;
-
-	md_dst = kmalloc(sizeof(*md_dst) + optslen, flags);
-	if (!md_dst)
-		return NULL;
-
-	rpl__metadata_dst_init(md_dst, type, optslen);
-
-	return md_dst;
-}
-static inline struct metadata_dst *rpl_tun_rx_dst(int md_size)
-{
-	struct metadata_dst *tun_dst;
-
-	tun_dst = erspan_rpl_metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
-	if (!tun_dst)
-		return NULL;
-
-	tun_dst->u.tun_info.options_len = 0;
-	tun_dst->u.tun_info.mode = 0;
-	return tun_dst;
-}
-static inline
-struct metadata_dst *rpl__ipv6_tun_set_dst(const struct in6_addr *saddr,
-					   const struct in6_addr *daddr,
-					    __u8 tos, __u8 ttl,
-					    __be16 tp_dst,
-					    __be32 label,
-					    __be16 flags,
-					    __be64 tunnel_id,
-					    int md_size)
-{
-	struct metadata_dst *tun_dst;
-	struct ip_tunnel_info *info;
-
-	tun_dst = rpl_tun_rx_dst(md_size);
-	if (!tun_dst)
-		return NULL;
-
-	info = &tun_dst->u.tun_info;
-	info->mode = IP_TUNNEL_INFO_IPV6;
-	info->key.tun_flags = flags;
-	info->key.tun_id = tunnel_id;
-	info->key.tp_src = 0;
-	info->key.tp_dst = tp_dst;
-
-	info->key.u.ipv6.src = *saddr;
-	info->key.u.ipv6.dst = *daddr;
-
-	info->key.tos = tos;
-	info->key.ttl = ttl;
-	info->key.label = label;
-
-	return tun_dst;
-}
-
-static inline struct metadata_dst *rpl_ipv6_tun_rx_dst(struct sk_buff *skb,
-						 __be16 flags,
-						 __be64 tunnel_id,
-						 int md_size)
-{
-	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
-
-	return rpl__ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
-				     ipv6_get_dsfield(ip6h), ip6h->hop_limit,
-				     0, ip6_flowlabel(ip6h), flags, tunnel_id,
-				     md_size);
-}
-
 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
 {
 	const struct ipv6hdr *ipv6h;
diff --git a/datapath/linux/compat/ip_gre.c b/datapath/linux/compat/ip_gre.c
index cf8803b53..77c5b4765 100644
--- a/datapath/linux/compat/ip_gre.c
+++ b/datapath/linux/compat/ip_gre.c
@@ -95,89 +95,11 @@ static __be32 tunnel_id_to_key(__be64 x)
 #endif
 }
 
-static struct dst_ops md_dst_ops = {
+/* Normally in net/core/dst.c but move it here */
+struct dst_ops md_dst_ops = {
 	.family =		AF_UNSPEC,
 };
 
-#ifndef DST_METADATA
-#define DST_METADATA 0x0080
-#endif
-
-static void rpl__metadata_dst_init(struct metadata_dst *md_dst,
-				enum metadata_type type, u8 optslen)
-
-{
-	struct dst_entry *dst;
-
-	dst = &md_dst->dst;
-	dst_init(dst, &md_dst_ops, NULL, 1, DST_OBSOLETE_NONE,
-		 DST_METADATA | DST_NOCOUNT);
-
-#if 0
-	/* unused in OVS */
-	dst->input = dst_md_discard;
-	dst->output = dst_md_discard_out;
-#endif
-	memset(dst + 1, 0, sizeof(*md_dst) + optslen - sizeof(*dst));
-	md_dst->type = type;
-}
-
-static struct metadata_dst *erspan_rpl_metadata_dst_alloc(u8 optslen, enum metadata_type type,
-					gfp_t flags)
-{
-	struct metadata_dst *md_dst;
-
-	md_dst = kmalloc(sizeof(*md_dst) + optslen, flags);
-	if (!md_dst)
-		return NULL;
-
-	rpl__metadata_dst_init(md_dst, type, optslen);
-
-	return md_dst;
-}
-static inline struct metadata_dst *rpl_tun_rx_dst(int md_size)
-{
-	struct metadata_dst *tun_dst;
-
-	tun_dst = erspan_rpl_metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
-	if (!tun_dst)
-		return NULL;
-
-	tun_dst->u.tun_info.options_len = 0;
-	tun_dst->u.tun_info.mode = 0;
-	return tun_dst;
-}
-static inline struct metadata_dst *rpl__ip_tun_set_dst(__be32 saddr,
-						    __be32 daddr,
-						    __u8 tos, __u8 ttl,
-						    __be16 tp_dst,
-						    __be16 flags,
-						    __be64 tunnel_id,
-						    int md_size)
-{
-	struct metadata_dst *tun_dst;
-
-	tun_dst = rpl_tun_rx_dst(md_size);
-	if (!tun_dst)
-		return NULL;
-
-	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
-			   saddr, daddr, tos, ttl,
-			   0, 0, tp_dst, tunnel_id, flags);
-	return tun_dst;
-}
-
-static inline struct metadata_dst *rpl_ip_tun_rx_dst(struct sk_buff *skb,
-						 __be16 flags,
-						 __be64 tunnel_id,
-						 int md_size)
-{
-	const struct iphdr *iph = ip_hdr(skb);
-
-	return rpl__ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
-				0, flags, tunnel_id, md_size);
-}
-
 static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
 		      int gre_hdr_len)
 {