[PATCH net-next 06/12] ipv4: Unmask upper DSCP bits when building flow key

[Ido Schimmel <idosch@nvidia.com>]

build_sk_flow_key() and __build_flow_key() are used to build an IPv4
flow key before calling one of the FIB lookup APIs.

Unmask the upper DSCP bits so that in the future the lookup could be
performed according to the full DSCP value.

Remove IPTOS_RT_MASK since it is no longer used.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
---
 include/net/route.h | 2 --
 net/ipv4/route.c    | 4 ++--
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/include/net/route.h b/include/net/route.h
index b896f086ec8e..1789f1e6640b 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -266,8 +266,6 @@ static inline void ip_rt_put(struct rtable *rt)
 	dst_release(&rt->dst);
 }
 
-#define IPTOS_RT_MASK	(IPTOS_TOS_MASK & ~3)
-
 extern const __u8 ip_tos2prio[16];
 
 static inline char rt_tos2priority(u8 tos)
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 5a77dc6d9c72..723ac9181558 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -512,7 +512,7 @@ static void __build_flow_key(const struct net *net, struct flowi4 *fl4,
 						    sk->sk_protocol;
 	}
 
-	flowi4_init_output(fl4, oif, mark, tos & IPTOS_RT_MASK, scope,
+	flowi4_init_output(fl4, oif, mark, tos & INET_DSCP_MASK, scope,
 			   prot, flow_flags, iph->daddr, iph->saddr, 0, 0,
 			   sock_net_uid(net, sk));
 }
@@ -541,7 +541,7 @@ static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
 	if (inet_opt && inet_opt->opt.srr)
 		daddr = inet_opt->opt.faddr;
 	flowi4_init_output(fl4, sk->sk_bound_dev_if, READ_ONCE(sk->sk_mark),
-			   ip_sock_rt_tos(sk) & IPTOS_RT_MASK,
+			   ip_sock_rt_tos(sk),
 			   ip_sock_rt_scope(sk),
 			   inet_test_bit(HDRINCL, sk) ?
 				IPPROTO_RAW : sk->sk_protocol,
-- 
2.46.0