xfrm: remove tos indirection from afinfo_policy

Only used by ipv4, we can read the fl4 tos value directly instead.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

include/net/xfrm.h

@@ -329,7 +329,6 @@ struct xfrm_policy_afinfo {
 	void			(*decode_session)(struct sk_buff *skb,
 						  struct flowi *fl,
 						  int reverse);
-	int			(*get_tos)(const struct flowi *fl);
 	int			(*init_path)(struct xfrm_dst *path,
 					     struct dst_entry *dst,
 					     int nfheader_len);

net/ipv4/xfrm4_policy.c

@@ -69,11 +69,6 @@ static int xfrm4_get_saddr(struct net *net, int oif,
 	return 0;
 }
 
-static int xfrm4_get_tos(const struct flowi *fl)
-{
-	return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; /* Strip ECN bits */
-}
-
 static int xfrm4_init_path(struct xfrm_dst *path, struct dst_entry *dst,
 			   int nfheader_len)
 {
@@ -272,7 +267,6 @@ static const struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
 	.dst_lookup =		xfrm4_dst_lookup,
 	.get_saddr =		xfrm4_get_saddr,
 	.decode_session =	_decode_session4,
-	.get_tos =		xfrm4_get_tos,
 	.init_path =		xfrm4_init_path,
 	.fill_dst =		xfrm4_fill_dst,
 	.blackhole_route =	ipv4_blackhole_route,

net/ipv6/xfrm6_policy.c

@@ -71,11 +71,6 @@ static int xfrm6_get_saddr(struct net *net, int oif,
 	return 0;
 }
 
-static int xfrm6_get_tos(const struct flowi *fl)
-{
-	return 0;
-}
-
 static int xfrm6_init_path(struct xfrm_dst *path, struct dst_entry *dst,
 			   int nfheader_len)
 {
@@ -292,7 +287,6 @@ static const struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
 	.dst_lookup =		xfrm6_dst_lookup,
 	.get_saddr =		xfrm6_get_saddr,
 	.decode_session =	_decode_session6,
-	.get_tos =		xfrm6_get_tos,
 	.init_path =		xfrm6_init_path,
 	.fill_dst =		xfrm6_fill_dst,
 	.blackhole_route =	ip6_blackhole_route,

net/xfrm/xfrm_policy.c

@@ -2450,18 +2450,10 @@ xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
 
 static int xfrm_get_tos(const struct flowi *fl, int family)
 {
-	const struct xfrm_policy_afinfo *afinfo;
-	int tos;
-
-	afinfo = xfrm_policy_get_afinfo(family);
-	if (!afinfo)
-		return 0;
-
-	tos = afinfo->get_tos(fl);
+	if (family == AF_INET)
+		return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
 
-	rcu_read_unlock();
-
-	return tos;
+	return 0;
 }
 
 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)