net: bridge: Move extack-setting to br_multicast_new_port_group()

Now that br_multicast_new_port_group() takes an extack argument, move
setting the extack there. The downside is that the error messages end
up being less specific (the function cannot distinguish between (S,G)
and (*,G) groups). However, the alternative is to check in the caller
whether the callee set the extack, and if it didn't, set it. But that
is only done when the callee is not exactly known. (E.g. in case of a
notifier invocation.)
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_mdb.c

@@ -850,10 +850,9 @@ static int br_mdb_add_group_sg(const struct br_mdb_config *cfg,
 
 	p = br_multicast_new_port_group(cfg->p, &cfg->group, *pp, flags, NULL,
 					MCAST_INCLUDE, cfg->rt_protocol, extack);
-	if (unlikely(!p)) {
-		NL_SET_ERR_MSG_MOD(extack, "Couldn't allocate new (S, G) port group");
+	if (unlikely(!p))
 		return -ENOMEM;
-	}
+
 	rcu_assign_pointer(*pp, p);
 	if (!(flags & MDB_PG_FLAGS_PERMANENT) && !cfg->src_entry)
 		mod_timer(&p->timer,
@@ -1077,10 +1076,8 @@ static int br_mdb_add_group_star_g(const struct br_mdb_config *cfg,
 	p = br_multicast_new_port_group(cfg->p, &cfg->group, *pp, flags, NULL,
 					cfg->filter_mode, cfg->rt_protocol,
 					extack);
-	if (unlikely(!p)) {
-		NL_SET_ERR_MSG_MOD(extack, "Couldn't allocate new (*, G) port group");
+	if (unlikely(!p))
 		return -ENOMEM;
-	}
 
 	err = br_mdb_add_group_srcs(cfg, p, brmctx, extack);
 	if (err)

net/bridge/br_multicast.c

@@ -1290,8 +1290,10 @@ struct net_bridge_port_group *br_multicast_new_port_group(
 	struct net_bridge_port_group *p;
 
 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
-	if (unlikely(!p))
+	if (unlikely(!p)) {
+		NL_SET_ERR_MSG_MOD(extack, "Couldn't allocate new port group");
 		return NULL;
+	}
 
 	p->key.addr = *group;
 	p->key.port = port;
@@ -1306,6 +1308,7 @@ struct net_bridge_port_group *br_multicast_new_port_group(
 	if (!br_multicast_is_star_g(group) &&
 	    rhashtable_lookup_insert_fast(&port->br->sg_port_tbl, &p->rhnode,
 					  br_sg_port_rht_params)) {
+		NL_SET_ERR_MSG_MOD(extack, "Couldn't insert new port group");
 		kfree(p);
 		return NULL;
 	}