net/sched: flower: Return error when hw can't offload and skip_sw is set

When skip_sw is set and hardware fails to apply filter, return error to
user. This will make error propagation logic similar to the one
currently used in u32 classifier.
Also, changed code to use tc_skip_sw() utility function.

Signed-off-by: Amir Vadai <[e-mail]>
Acked-by: Jiri Pirko <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/sched/cls_flower.c

···
 	f = rhashtable_lookup_fast(&head->ht,
 				   fl_key_get_start(&skb_mkey, &head->mask),
 				   head->ht_params);
-	if (f && !(f->flags & TCA_CLS_FLAGS_SKIP_SW)) {
+	if (f && !tc_skip_sw(f->flags)) {
 		*res = f->res;
 		return tcf_exts_exec(skb, &f->exts, res);
 	}
···
 	dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol, &tc);
 }
 
-static void fl_hw_replace_filter(struct tcf_proto *tp,
-				 struct flow_dissector *dissector,
-				 struct fl_flow_key *mask,
-				 struct fl_flow_key *key,
-				 struct tcf_exts *actions,
-				 unsigned long cookie, u32 flags)
+static int fl_hw_replace_filter(struct tcf_proto *tp,
+				struct flow_dissector *dissector,
+				struct fl_flow_key *mask,
+				struct fl_flow_key *key,
+				struct tcf_exts *actions,
+				unsigned long cookie, u32 flags)
 {
 	struct net_device *dev = tp->q->dev_queue->dev;
 	struct tc_cls_flower_offload offload = {0};
 	struct tc_to_netdev tc;
+	int err;
 
 	if (!tc_should_offload(dev, tp, flags))
-		return;
+		return tc_skip_sw(flags) ? -EINVAL : 0;
 
 	offload.command = TC_CLSFLOWER_REPLACE;
 	offload.cookie = cookie;
···
 	tc.type = TC_SETUP_CLSFLOWER;
 	tc.cls_flower = &offload;
 
-	dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol, &tc);
+	err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol, &tc);
+
+	if (tc_skip_sw(flags))
+		return err;
+
+	return 0;
 }
 
 static void fl_hw_update_stats(struct tcf_proto *tp, struct cls_fl_filter *f)
···
 	if (err)
 		goto errout;
 
-	if (!(fnew->flags & TCA_CLS_FLAGS_SKIP_SW)) {
+	if (!tc_skip_sw(fnew->flags)) {
 		err = rhashtable_insert_fast(&head->ht, &fnew->ht_node,
 					     head->ht_params);
 		if (err)
 			goto errout;
 	}
 
-	fl_hw_replace_filter(tp,
-			     &head->dissector,
-			     &mask.key,
-			     &fnew->key,
-			     &fnew->exts,
-			     (unsigned long)fnew,
-			     fnew->flags);
+	err = fl_hw_replace_filter(tp,
+				   &head->dissector,
+				   &mask.key,
+				   &fnew->key,
+				   &fnew->exts,
+				   (unsigned long)fnew,
+				   fnew->flags);
+	if (err)
+		goto errout;
 
 	if (fold) {
 		rhashtable_remove_fast(&head->ht, &fold->ht_node,