net: dsa: clean up dsa_user_add_cls_matchall()

The body is a bit hard to read, hard to extend, and has duplicated
conditions.

Clean up the "if (many conditions) else if (many conditions, some
of them repeated)" pattern by:

- Moving the repeated conditions out
- Replacing the repeated tests for the same variable with a switch/case
- Moving the protocol check inside the dsa_user_add_cls_matchall_mirred()
  function call.

This is pure refactoring, no logic has been changed, though some tests
were reordered. The order does not matter - they are independent things
to be tested for.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241023135251.1752488-3-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/dsa/user.c b/net/dsa/user.c
index 91a1fa5f8ab0ef386059a81914dd27242c209b5b..15f69fa6a38ba4cd980b3435fdbc101c5087d861 100644 (file)
--- a/net/dsa/user.c
+++ b/net/dsa/user.c
@@ -1376,6 +1376,9 @@ dsa_user_add_cls_matchall_mirred(struct net_device *dev,
        struct dsa_port *to_dp;
        int err;
 
+       if (cls->common.protocol != htons(ETH_P_ALL))
+               return -EOPNOTSUPP;
+
        if (!ds->ops->port_mirror_add)
                return -EOPNOTSUPP;
 
@@ -1485,17 +1488,21 @@ static int dsa_user_add_cls_matchall(struct net_device *dev,
                                     struct tc_cls_matchall_offload *cls,
                                     bool ingress)
 {
-       int err = -EOPNOTSUPP;
+       const struct flow_action *action = &cls->rule->action;
 
-       if (cls->common.protocol == htons(ETH_P_ALL) &&
-           flow_offload_has_one_action(&cls->rule->action) &&
-           cls->rule->action.entries[0].id == FLOW_ACTION_MIRRED)
-               err = dsa_user_add_cls_matchall_mirred(dev, cls, ingress);
-       else if (flow_offload_has_one_action(&cls->rule->action) &&
-                cls->rule->action.entries[0].id == FLOW_ACTION_POLICE)
-               err = dsa_user_add_cls_matchall_police(dev, cls, ingress);
+       if (!flow_offload_has_one_action(action))
+               return -EOPNOTSUPP;
 
-       return err;
+       switch (action->entries[0].id) {
+       case FLOW_ACTION_MIRRED:
+               return dsa_user_add_cls_matchall_mirred(dev, cls, ingress);
+       case FLOW_ACTION_POLICE:
+               return dsa_user_add_cls_matchall_police(dev, cls, ingress);
+       default:
+               break;
+       }
+
+       return -EOPNOTSUPP;
 }
 
 static void dsa_user_del_cls_matchall(struct net_device *dev,