net: sched: fix tc_should_offload for specific clsact classes

When offloading classifiers such as u32 or flower to hardware, and the
qdisc is clsact (TC_H_CLSACT), then we need to differentiate its classes,
since not all of them handle ingress, therefore we must leave those in
software path. Add a .tcf_cl_offload() callback, so we can generically
handle them, tested on ixgbe.

Fixes: 10cbc68434 ("net/sched: cls_flower: Hardware offloaded filters statistics support")
Fixes: 5b33f48842 ("net/flower: Introduce hardware offload support")
Fixes: a1b7c5fd7f ("net: sched: add cls_u32 offload hooks for netdevs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/sch_ingress.c

@@ -27,6 +27,11 @@ static unsigned long ingress_get(struct Qdisc *sch, u32 classid)
 	return TC_H_MIN(classid) + 1;
 }
 
+static bool ingress_cl_offload(u32 classid)
+{
+	return true;
+}
+
 static unsigned long ingress_bind_filter(struct Qdisc *sch,
 					 unsigned long parent, u32 classid)
 {
@@ -86,6 +91,7 @@ static const struct Qdisc_class_ops ingress_class_ops = {
 	.put		=	ingress_put,
 	.walk		=	ingress_walk,
 	.tcf_chain	=	ingress_find_tcf,
+	.tcf_cl_offload	=	ingress_cl_offload,
 	.bind_tcf	=	ingress_bind_filter,
 	.unbind_tcf	=	ingress_put,
 };
@@ -110,6 +116,11 @@ static unsigned long clsact_get(struct Qdisc *sch, u32 classid)
 	}
 }
 
+static bool clsact_cl_offload(u32 classid)
+{
+	return TC_H_MIN(classid) == TC_H_MIN(TC_H_MIN_INGRESS);
+}
+
 static unsigned long clsact_bind_filter(struct Qdisc *sch,
 					unsigned long parent, u32 classid)
 {
@@ -158,6 +169,7 @@ static const struct Qdisc_class_ops clsact_class_ops = {
 	.put		=	ingress_put,
 	.walk		=	ingress_walk,
 	.tcf_chain	=	clsact_find_tcf,
+	.tcf_cl_offload	=	clsact_cl_offload,
 	.bind_tcf	=	clsact_bind_filter,
 	.unbind_tcf	=	ingress_put,
 };