ipv4: Drop tos parameter from flowi4_update_output()
authorGuillaume Nault <gnault@redhat.com>
Thu, 1 Jun 2023 16:37:46 +0000 (18:37 +0200)
committerDavid S. Miller <davem@davemloft.net>
Fri, 2 Jun 2023 09:52:38 +0000 (10:52 +0100)
Callers of flowi4_update_output() never try to update ->flowi4_tos:

  * ip_route_connect() updates ->flowi4_tos with its own current
    value.

  * ip_route_newports() has two users: tcp_v4_connect() and
    dccp_v4_connect. Both initialise fl4 with ip_route_connect(), which
    in turn sets ->flowi4_tos with RT_TOS(inet_sk(sk)->tos) and
    ->flowi4_scope based on SOCK_LOCALROUTE.

    Then ip_route_newports() updates ->flowi4_tos with
    RT_CONN_FLAGS(sk), which is the same as RT_TOS(inet_sk(sk)->tos),
    unless SOCK_LOCALROUTE is set on the socket. In that case, the
    lowest order bit is set to 1, to eventually inform
    ip_route_output_key_hash() to restrict the scope to RT_SCOPE_LINK.
    This is equivalent to properly setting ->flowi4_scope as
    ip_route_connect() did.

  * ip_vs_xmit.c initialises ->flowi4_tos with memset(0), then calls
    flowi4_update_output() with tos=0.

  * sctp_v4_get_dst() uses the same RT_CONN_FLAGS_TOS() when
    initialising ->flowi4_tos and when calling flowi4_update_output().

In the end, ->flowi4_tos never changes. So let's just drop the tos
parameter. This will simplify the conversion of ->flowi4_tos from __u8
to dscp_t.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/flow.h
include/net/route.h
net/netfilter/ipvs/ip_vs_xmit.c
net/sctp/protocol.c

index bb8651a..7f0adda 100644 (file)
@@ -116,11 +116,10 @@ static inline void flowi4_init_output(struct flowi4 *fl4, int oif,
 }
 
 /* Reset some input parameters after previous lookup */
-static inline void flowi4_update_output(struct flowi4 *fl4, int oif, __u8 tos,
+static inline void flowi4_update_output(struct flowi4 *fl4, int oif,
                                        __be32 daddr, __be32 saddr)
 {
        fl4->flowi4_oif = oif;
-       fl4->flowi4_tos = tos;
        fl4->daddr = daddr;
        fl4->saddr = saddr;
 }
index bcc367c..5a5c726 100644 (file)
@@ -321,8 +321,7 @@ static inline struct rtable *ip_route_connect(struct flowi4 *fl4, __be32 dst,
                if (IS_ERR(rt))
                        return rt;
                ip_rt_put(rt);
-               flowi4_update_output(fl4, oif, fl4->flowi4_tos, fl4->daddr,
-                                    fl4->saddr);
+               flowi4_update_output(fl4, oif, fl4->daddr, fl4->saddr);
        }
        security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
        return ip_route_output_flow(net, fl4, sk);
@@ -337,8 +336,7 @@ static inline struct rtable *ip_route_newports(struct flowi4 *fl4, struct rtable
                fl4->fl4_dport = dport;
                fl4->fl4_sport = sport;
                ip_rt_put(rt);
-               flowi4_update_output(fl4, sk->sk_bound_dev_if,
-                                    RT_CONN_FLAGS(sk), fl4->daddr,
+               flowi4_update_output(fl4, sk->sk_bound_dev_if, fl4->daddr,
                                     fl4->saddr);
                security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
                return ip_route_output_flow(sock_net(sk), fl4, sk);
index feb1d7f..c7652da 100644 (file)
@@ -139,7 +139,7 @@ retry:
                if (PTR_ERR(rt) == -EINVAL && *saddr &&
                    rt_mode & IP_VS_RT_MODE_CONNECT && !loop) {
                        *saddr = 0;
-                       flowi4_update_output(&fl4, 0, 0, daddr, 0);
+                       flowi4_update_output(&fl4, 0, daddr, 0);
                        goto retry;
                }
                IP_VS_DBG_RL("ip_route_output error, dest: %pI4\n", &daddr);
@@ -147,7 +147,7 @@ retry:
        } else if (!*saddr && rt_mode & IP_VS_RT_MODE_CONNECT && fl4.saddr) {
                ip_rt_put(rt);
                *saddr = fl4.saddr;
-               flowi4_update_output(&fl4, 0, 0, daddr, fl4.saddr);
+               flowi4_update_output(&fl4, 0, daddr, fl4.saddr);
                loop = true;
                goto retry;
        }
index c365df2..664d1f2 100644 (file)
@@ -500,9 +500,7 @@ static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
                        continue;
 
                fl4->fl4_sport = laddr->a.v4.sin_port;
-               flowi4_update_output(fl4,
-                                    asoc->base.sk->sk_bound_dev_if,
-                                    RT_CONN_FLAGS_TOS(asoc->base.sk, tos),
+               flowi4_update_output(fl4, asoc->base.sk->sk_bound_dev_if,
                                     daddr->v4.sin_addr.s_addr,
                                     laddr->a.v4.sin_addr.s_addr);