ipv4: Use dscp_t in struct fib_entry_notifier_info

Use the new dscp_t type to replace the tos field of struct
fib_entry_notifier_info. This ensures ECN bits are ignored and makes it
compatible with the dscp field of struct fib_rt_info.

This also allows sparse to flag potential incorrect uses of DSCP and
ECN bits.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/marvell/prestera/prestera_router.c

@@ -89,7 +89,7 @@ prestera_kern_fib_cache_destroy(struct prestera_switch *sw,
 static struct prestera_kern_fib_cache *
 prestera_kern_fib_cache_create(struct prestera_switch *sw,
 			       struct prestera_kern_fib_cache_key *key,
-			       struct fib_info *fi, u8 tos, u8 type)
+			       struct fib_info *fi, dscp_t dscp, u8 type)
 {
 	struct prestera_kern_fib_cache *fib_cache;
 	int err;
@@ -101,7 +101,7 @@ prestera_kern_fib_cache_create(struct prestera_switch *sw,
 	memcpy(&fib_cache->key, key, sizeof(*key));
 	fib_info_hold(fi);
 	fib_cache->fi = fi;
-	fib_cache->kern_tos = tos;
+	fib_cache->kern_tos = inet_dscp_to_dsfield(dscp);
 	fib_cache->kern_type = type;
 
 	err = rhashtable_insert_fast(&sw->router->kern_fib_cache_ht,
@@ -306,7 +306,7 @@ prestera_k_arb_fib_evt(struct prestera_switch *sw,
 	if (replace) {
 		fib_cache = prestera_kern_fib_cache_create(sw, &fc_key,
 							   fen_info->fi,
-							   fen_info->tos,
+							   fen_info->dscp,
 							   fen_info->type);
 		if (!fib_cache) {
 			dev_err(sw->dev->dev, "fib_cache == NULL");

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

@@ -5621,7 +5621,7 @@ mlxsw_sp_fib4_offload_failed_flag_set(struct mlxsw_sp *mlxsw_sp,
 	fri.tb_id = fen_info->tb_id;
 	fri.dst = cpu_to_be32(*p_dst);
 	fri.dst_len = fen_info->dst_len;
-	fri.dscp = inet_dsfield_to_dscp(fen_info->tos);
+	fri.dscp = fen_info->dscp;
 	fri.type = fen_info->type;
 	fri.offload = false;
 	fri.trap = false;
@@ -6251,7 +6251,7 @@ mlxsw_sp_fib4_entry_create(struct mlxsw_sp *mlxsw_sp,
 	fib_info_hold(fib4_entry->fi);
 	fib4_entry->tb_id = fen_info->tb_id;
 	fib4_entry->type = fen_info->type;
-	fib4_entry->tos = fen_info->tos;
+	fib4_entry->tos = inet_dscp_to_dsfield(fen_info->dscp);
 
 	fib_entry->fib_node = fib_node;
 
@@ -6305,7 +6305,7 @@ mlxsw_sp_fib4_entry_lookup(struct mlxsw_sp *mlxsw_sp,
 	fib4_entry = container_of(fib_node->fib_entry,
 				  struct mlxsw_sp_fib4_entry, common);
 	if (fib4_entry->tb_id == fen_info->tb_id &&
-	    fib4_entry->tos == fen_info->tos &&
+	    fib4_entry->tos == inet_dscp_to_dsfield(fen_info->dscp) &&
 	    fib4_entry->type == fen_info->type &&
 	    fib4_entry->fi == fen_info->fi)
 		return fib4_entry;

drivers/net/netdevsim/fib.c

@@ -284,7 +284,7 @@ nsim_fib4_rt_create(struct nsim_fib_data *data,
 
 	fib4_rt->fi = fen_info->fi;
 	fib_info_hold(fib4_rt->fi);
-	fib4_rt->tos = fen_info->tos;
+	fib4_rt->tos = inet_dscp_to_dsfield(fen_info->dscp);
 	fib4_rt->type = fen_info->type;
 
 	return fib4_rt;
@@ -323,7 +323,7 @@ nsim_fib4_rt_offload_failed_flag_set(struct net *net,
 	fri.tb_id = fen_info->tb_id;
 	fri.dst = cpu_to_be32(*p_dst);
 	fri.dst_len = fen_info->dst_len;
-	fri.dscp = inet_dsfield_to_dscp(fen_info->tos);
+	fri.dscp = fen_info->dscp;
 	fri.type = fen_info->type;
 	fri.offload = false;
 	fri.trap = false;

include/net/ip_fib.h

@@ -225,7 +225,7 @@ struct fib_entry_notifier_info {
 	u32 dst;
 	int dst_len;
 	struct fib_info *fi;
-	u8 tos;
+	dscp_t dscp;
 	u8 type;
 	u32 tb_id;
 };

net/ipv4/fib_trie.c

@@ -82,7 +82,7 @@ static int call_fib_entry_notifier(struct notifier_block *nb,
 		.dst = dst,
 		.dst_len = dst_len,
 		.fi = fa->fa_info,
-		.tos = inet_dscp_to_dsfield(fa->fa_dscp),
+		.dscp = fa->fa_dscp,
 		.type = fa->fa_type,
 		.tb_id = fa->tb_id,
 	};
@@ -99,7 +99,7 @@ static int call_fib_entry_notifiers(struct net *net,
 		.dst = dst,
 		.dst_len = dst_len,
 		.fi = fa->fa_info,
-		.tos = inet_dscp_to_dsfield(fa->fa_dscp),
+		.dscp = fa->fa_dscp,
 		.type = fa->fa_type,
 		.tb_id = fa->tb_id,
 	};