nfp: flower-ct: add pre and post ct checks

Add checks to see if a flow is a conntrack flow we can potentially
handle. Just stub out the handling the different conntrack flows.

Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Yinjun Zhang <yinjun.zhang@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/Makefile

@@ -51,7 +51,8 @@ nfp-objs += \
 	    flower/metadata.o \
 	    flower/offload.o \
 	    flower/tunnel_conf.o \
-	    flower/qos_conf.o
+	    flower/qos_conf.o \
+	    flower/conntrack.o
 endif
 
 ifeq ($(CONFIG_BPF_SYSCALL),y)

drivers/net/ethernet/netronome/nfp/flower/conntrack.c

@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (C) 2021 Corigine, Inc. */
+
+#include "conntrack.h"
+
+bool is_pre_ct_flow(struct flow_cls_offload *flow)
+{
+	struct flow_action_entry *act;
+	int i;
+
+	flow_action_for_each(i, act, &flow->rule->action) {
+		if (act->id == FLOW_ACTION_CT && !act->ct.action)
+			return true;
+	}
+	return false;
+}
+
+bool is_post_ct_flow(struct flow_cls_offload *flow)
+{
+	struct flow_rule *rule = flow_cls_offload_flow_rule(flow);
+	struct flow_dissector *dissector = rule->match.dissector;
+	struct flow_match_ct ct;
+
+	if (dissector->used_keys & BIT(FLOW_DISSECTOR_KEY_CT)) {
+		flow_rule_match_ct(rule, &ct);
+		if (ct.key->ct_state & TCA_FLOWER_KEY_CT_FLAGS_ESTABLISHED)
+			return true;
+	}
+	return false;
+}
+
+int nfp_fl_ct_handle_pre_ct(struct nfp_flower_priv *priv,
+			    struct net_device *netdev,
+			    struct flow_cls_offload *flow,
+			    struct netlink_ext_ack *extack)
+{
+	NL_SET_ERR_MSG_MOD(extack, "unsupported offload: Conntrack action not supported");
+	return -EOPNOTSUPP;
+}
+
+int nfp_fl_ct_handle_post_ct(struct nfp_flower_priv *priv,
+			     struct net_device *netdev,
+			     struct flow_cls_offload *flow,
+			     struct netlink_ext_ack *extack)
+{
+	NL_SET_ERR_MSG_MOD(extack, "unsupported offload: Conntrack match not supported");
+	return -EOPNOTSUPP;
+}

drivers/net/ethernet/netronome/nfp/flower/conntrack.h

@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+/* Copyright (C) 2021 Corigine, Inc. */
+
+#ifndef __NFP_FLOWER_CONNTRACK_H__
+#define __NFP_FLOWER_CONNTRACK_H__ 1
+
+#include "main.h"
+
+bool is_pre_ct_flow(struct flow_cls_offload *flow);
+bool is_post_ct_flow(struct flow_cls_offload *flow);
+
+/**
+ * nfp_fl_ct_handle_pre_ct() - Handles -trk conntrack rules
+ * @priv:	Pointer to app priv
+ * @netdev:	netdev structure.
+ * @flow:	TC flower classifier offload structure.
+ * @extack:	Extack pointer for errors
+ *
+ * Adds a new entry to the relevant zone table and tries to
+ * merge with other +trk+est entries and offload if possible.
+ *
+ * Return: negative value on error, 0 if configured successfully.
+ */
+int nfp_fl_ct_handle_pre_ct(struct nfp_flower_priv *priv,
+			    struct net_device *netdev,
+			    struct flow_cls_offload *flow,
+			    struct netlink_ext_ack *extack);
+/**
+ * nfp_fl_ct_handle_post_ct() - Handles +trk+est conntrack rules
+ * @priv:	Pointer to app priv
+ * @netdev:	netdev structure.
+ * @flow:	TC flower classifier offload structure.
+ * @extack:	Extack pointer for errors
+ *
+ * Adds a new entry to the relevant zone table and tries to
+ * merge with other -trk entries and offload if possible.
+ *
+ * Return: negative value on error, 0 if configured successfully.
+ */
+int nfp_fl_ct_handle_post_ct(struct nfp_flower_priv *priv,
+			     struct net_device *netdev,
+			     struct flow_cls_offload *flow,
+			     struct netlink_ext_ack *extack);
+
+#endif

drivers/net/ethernet/netronome/nfp/flower/offload.c

@@ -7,6 +7,7 @@
 
 #include "cmsg.h"
 #include "main.h"
+#include "conntrack.h"
 #include "../nfpcore/nfp_cpp.h"
 #include "../nfpcore/nfp_nsp.h"
 #include "../nfp_app.h"
@@ -1316,6 +1317,12 @@ nfp_flower_add_offload(struct nfp_app *app, struct net_device *netdev,
 	if (nfp_netdev_is_nfp_repr(netdev))
 		port = nfp_port_from_netdev(netdev);
 
+	if (is_pre_ct_flow(flow))
+		return nfp_fl_ct_handle_pre_ct(priv, netdev, flow, extack);
+
+	if (is_post_ct_flow(flow))
+		return nfp_fl_ct_handle_post_ct(priv, netdev, flow, extack);
+
 	if (!offload_pre_check(flow))
 		return -EOPNOTSUPP;