net: mscc: ocelot: Hardware ofload for tc flower filter

Hardware offload of port filtering are now supported via tc command using
flower filter. ACL rules are used to enable the hardware offload.
The following keys are supported:

vlan_id
vlan_prio
dst_mac/src_mac for non IP frames
dst_ip/src_ip
dst_port/src_port

The following actions are supported:
trap
drop

These filters are supported only on the ingress schedulare.

Add:
tc qdisc add dev eth3 ingress
tc filter ad dev eth3 parent ffff: ip_proto ip flower \
    ip_proto tcp dst_port 80 action drop

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mscc/Makefile

@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: (GPL-2.0 OR MIT)
 obj-$(CONFIG_MSCC_OCELOT_SWITCH) += mscc_ocelot_common.o
 mscc_ocelot_common-y := ocelot.o ocelot_io.o
-mscc_ocelot_common-y += ocelot_regs.o ocelot_tc.o ocelot_police.o ocelot_ace.o
+mscc_ocelot_common-y += ocelot_regs.o ocelot_tc.o ocelot_police.o ocelot_ace.o ocelot_flower.o
 obj-$(CONFIG_MSCC_OCELOT_SWITCH_OCELOT) += ocelot_board.o

drivers/net/ethernet/mscc/ocelot_ace.h

@@ -224,4 +224,9 @@ int ocelot_ace_rule_stats_update(struct ocelot_ace_rule *rule);
 int ocelot_ace_init(struct ocelot *ocelot);
 void ocelot_ace_deinit(void);
 
+int ocelot_setup_tc_block_flower_bind(struct ocelot_port *port,
+				      struct tc_block_offload *f);
+void ocelot_setup_tc_block_flower_unbind(struct ocelot_port *port,
+					 struct tc_block_offload *f);
+
 #endif /* _MSCC_OCELOT_ACE_H_ */

drivers/net/ethernet/mscc/ocelot_flower.c

@@ -0,0 +1,357 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/* Microsemi Ocelot Switch driver
+ * Copyright (c) 2019 Microsemi Corporation
+ */
+
+#include <net/pkt_cls.h>
+#include <net/tc_act/tc_gact.h>
+
+#include "ocelot_ace.h"
+
+struct ocelot_port_block {
+	struct ocelot_acl_block *block;
+	struct ocelot_port *port;
+};
+
+static u16 get_prio(u32 prio)
+{
+	/* prio starts from 0x1000 while the ids starts from 0 */
+	return prio >> 16;
+}
+
+static int ocelot_flower_parse_action(struct tc_cls_flower_offload *f,
+				      struct ocelot_ace_rule *rule)
+{
+	const struct flow_action_entry *a;
+	int i;
+
+	if (f->rule->action.num_entries != 1)
+		return -EOPNOTSUPP;
+
+	flow_action_for_each(i, a, &f->rule->action) {
+		switch (a->id) {
+		case FLOW_ACTION_DROP:
+			rule->action = OCELOT_ACL_ACTION_DROP;
+			break;
+		case FLOW_ACTION_TRAP:
+			rule->action = OCELOT_ACL_ACTION_TRAP;
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+	}
+
+	return 0;
+}
+
+static int ocelot_flower_parse(struct tc_cls_flower_offload *f,
+			       struct ocelot_ace_rule *ocelot_rule)
+{
+	struct flow_rule *rule = tc_cls_flower_offload_flow_rule(f);
+	struct flow_dissector *dissector = rule->match.dissector;
+
+	if (dissector->used_keys &
+	    ~(BIT(FLOW_DISSECTOR_KEY_CONTROL) |
+	      BIT(FLOW_DISSECTOR_KEY_BASIC) |
+	      BIT(FLOW_DISSECTOR_KEY_PORTS) |
+	      BIT(FLOW_DISSECTOR_KEY_VLAN) |
+	      BIT(FLOW_DISSECTOR_KEY_IPV4_ADDRS) |
+	      BIT(FLOW_DISSECTOR_KEY_IPV6_ADDRS) |
+	      BIT(FLOW_DISSECTOR_KEY_ETH_ADDRS))) {
+		return -EOPNOTSUPP;
+	}
+
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_CONTROL)) {
+		struct flow_match_control match;
+
+		flow_rule_match_control(rule, &match);
+	}
+
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
+		struct flow_match_eth_addrs match;
+		u16 proto = ntohs(f->common.protocol);
+
+		/* The hw support mac matches only for MAC_ETYPE key,
+		 * therefore if other matches(port, tcp flags, etc) are added
+		 * then just bail out
+		 */
+		if ((dissector->used_keys &
+		    (BIT(FLOW_DISSECTOR_KEY_ETH_ADDRS) |
+		     BIT(FLOW_DISSECTOR_KEY_BASIC) |
+		     BIT(FLOW_DISSECTOR_KEY_CONTROL))) !=
+		    (BIT(FLOW_DISSECTOR_KEY_ETH_ADDRS) |
+		     BIT(FLOW_DISSECTOR_KEY_BASIC) |
+		     BIT(FLOW_DISSECTOR_KEY_CONTROL)))
+			return -EOPNOTSUPP;
+
+		if (proto == ETH_P_IP ||
+		    proto == ETH_P_IPV6 ||
+		    proto == ETH_P_ARP)
+			return -EOPNOTSUPP;
+
+		flow_rule_match_eth_addrs(rule, &match);
+		ocelot_rule->type = OCELOT_ACE_TYPE_ETYPE;
+		ether_addr_copy(ocelot_rule->frame.etype.dmac.value,
+				match.key->dst);
+		ether_addr_copy(ocelot_rule->frame.etype.smac.value,
+				match.key->src);
+		ether_addr_copy(ocelot_rule->frame.etype.dmac.mask,
+				match.mask->dst);
+		ether_addr_copy(ocelot_rule->frame.etype.smac.mask,
+				match.mask->src);
+		goto finished_key_parsing;
+	}
+
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_BASIC)) {
+		struct flow_match_basic match;
+
+		flow_rule_match_basic(rule, &match);
+		if (ntohs(match.key->n_proto) == ETH_P_IP) {
+			ocelot_rule->type = OCELOT_ACE_TYPE_IPV4;
+			ocelot_rule->frame.ipv4.proto.value[0] =
+				match.key->ip_proto;
+			ocelot_rule->frame.ipv4.proto.mask[0] =
+				match.mask->ip_proto;
+		}
+		if (ntohs(match.key->n_proto) == ETH_P_IPV6) {
+			ocelot_rule->type = OCELOT_ACE_TYPE_IPV6;
+			ocelot_rule->frame.ipv6.proto.value[0] =
+				match.key->ip_proto;
+			ocelot_rule->frame.ipv6.proto.mask[0] =
+				match.mask->ip_proto;
+		}
+	}
+
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_IPV4_ADDRS) &&
+	    ntohs(f->common.protocol) == ETH_P_IP) {
+		struct flow_match_ipv4_addrs match;
+		u8 *tmp;
+
+		flow_rule_match_ipv4_addrs(rule, &match);
+		tmp = &ocelot_rule->frame.ipv4.sip.value.addr[0];
+		memcpy(tmp, &match.key->src, 4);
+
+		tmp = &ocelot_rule->frame.ipv4.sip.mask.addr[0];
+		memcpy(tmp, &match.mask->src, 4);
+
+		tmp = &ocelot_rule->frame.ipv4.dip.value.addr[0];
+		memcpy(tmp, &match.key->dst, 4);
+
+		tmp = &ocelot_rule->frame.ipv4.dip.mask.addr[0];
+		memcpy(tmp, &match.mask->dst, 4);
+	}
+
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_IPV6_ADDRS) &&
+	    ntohs(f->common.protocol) == ETH_P_IPV6) {
+		return -EOPNOTSUPP;
+	}
+
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_PORTS)) {
+		struct flow_match_ports match;
+
+		flow_rule_match_ports(rule, &match);
+		ocelot_rule->frame.ipv4.sport.value = ntohs(match.key->src);
+		ocelot_rule->frame.ipv4.sport.mask = ntohs(match.mask->src);
+		ocelot_rule->frame.ipv4.dport.value = ntohs(match.key->dst);
+		ocelot_rule->frame.ipv4.dport.mask = ntohs(match.mask->dst);
+	}
+
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_VLAN)) {
+		struct flow_match_vlan match;
+
+		flow_rule_match_vlan(rule, &match);
+		ocelot_rule->type = OCELOT_ACE_TYPE_ANY;
+		ocelot_rule->vlan.vid.value = match.key->vlan_id;
+		ocelot_rule->vlan.vid.mask = match.mask->vlan_id;
+		ocelot_rule->vlan.pcp.value[0] = match.key->vlan_priority;
+		ocelot_rule->vlan.pcp.mask[0] = match.mask->vlan_priority;
+	}
+
+finished_key_parsing:
+	ocelot_rule->prio = get_prio(f->common.prio);
+	ocelot_rule->id = f->cookie;
+	return ocelot_flower_parse_action(f, ocelot_rule);
+}
+
+static
+struct ocelot_ace_rule *ocelot_ace_rule_create(struct tc_cls_flower_offload *f,
+					       struct ocelot_port_block *block)
+{
+	struct ocelot_ace_rule *rule;
+
+	rule = kzalloc(sizeof(*rule), GFP_KERNEL);
+	if (!rule)
+		return NULL;
+
+	rule->port = block->port;
+	rule->chip_port = block->port->chip_port;
+	return rule;
+}
+
+static int ocelot_flower_replace(struct tc_cls_flower_offload *f,
+				 struct ocelot_port_block *port_block)
+{
+	struct ocelot_ace_rule *rule;
+	int ret;
+
+	rule = ocelot_ace_rule_create(f, port_block);
+	if (!rule)
+		return -ENOMEM;
+
+	ret = ocelot_flower_parse(f, rule);
+	if (ret) {
+		kfree(rule);
+		return ret;
+	}
+
+	ret = ocelot_ace_rule_offload_add(rule);
+	if (ret)
+		return ret;
+
+	port_block->port->tc.offload_cnt++;
+	return 0;
+}
+
+static int ocelot_flower_destroy(struct tc_cls_flower_offload *f,
+				 struct ocelot_port_block *port_block)
+{
+	struct ocelot_ace_rule rule;
+	int ret;
+
+	rule.prio = get_prio(f->common.prio);
+	rule.port = port_block->port;
+	rule.id = f->cookie;
+
+	ret = ocelot_ace_rule_offload_del(&rule);
+	if (ret)
+		return ret;
+
+	port_block->port->tc.offload_cnt--;
+	return 0;
+}
+
+static int ocelot_flower_stats_update(struct tc_cls_flower_offload *f,
+				      struct ocelot_port_block *port_block)
+{
+	struct ocelot_ace_rule rule;
+	int ret;
+
+	rule.prio = get_prio(f->common.prio);
+	rule.port = port_block->port;
+	rule.id = f->cookie;
+	ret = ocelot_ace_rule_stats_update(&rule);
+	if (ret)
+		return ret;
+
+	flow_stats_update(&f->stats, 0x0, rule.stats.pkts, 0x0);
+	return 0;
+}
+
+static int ocelot_setup_tc_cls_flower(struct tc_cls_flower_offload *f,
+				      struct ocelot_port_block *port_block)
+{
+	switch (f->command) {
+	case TC_CLSFLOWER_REPLACE:
+		return ocelot_flower_replace(f, port_block);
+	case TC_CLSFLOWER_DESTROY:
+		return ocelot_flower_destroy(f, port_block);
+	case TC_CLSFLOWER_STATS:
+		return ocelot_flower_stats_update(f, port_block);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int ocelot_setup_tc_block_cb_flower(enum tc_setup_type type,
+					   void *type_data, void *cb_priv)
+{
+	struct ocelot_port_block *port_block = cb_priv;
+
+	if (!tc_cls_can_offload_and_chain0(port_block->port->dev, type_data))
+		return -EOPNOTSUPP;
+
+	switch (type) {
+	case TC_SETUP_CLSFLOWER:
+		return ocelot_setup_tc_cls_flower(type_data, cb_priv);
+	case TC_SETUP_CLSMATCHALL:
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static struct ocelot_port_block*
+ocelot_port_block_create(struct ocelot_port *port)
+{
+	struct ocelot_port_block *port_block;
+
+	port_block = kzalloc(sizeof(*port_block), GFP_KERNEL);
+	if (!port_block)
+		return NULL;
+
+	port_block->port = port;
+
+	return port_block;
+}
+
+static void ocelot_port_block_destroy(struct ocelot_port_block *block)
+{
+	kfree(block);
+}
+
+int ocelot_setup_tc_block_flower_bind(struct ocelot_port *port,
+				      struct tc_block_offload *f)
+{
+	struct ocelot_port_block *port_block;
+	struct tcf_block_cb *block_cb;
+	int ret;
+
+	if (f->binder_type == TCF_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
+		return -EOPNOTSUPP;
+
+	block_cb = tcf_block_cb_lookup(f->block,
+				       ocelot_setup_tc_block_cb_flower, port);
+	if (!block_cb) {
+		port_block = ocelot_port_block_create(port);
+		if (!port_block)
+			return -ENOMEM;
+
+		block_cb =
+			__tcf_block_cb_register(f->block,
+						ocelot_setup_tc_block_cb_flower,
+						port, port_block, f->extack);
+		if (IS_ERR(block_cb)) {
+			ret = PTR_ERR(block_cb);
+			goto err_cb_register;
+		}
+	} else {
+		port_block = tcf_block_cb_priv(block_cb);
+	}
+
+	tcf_block_cb_incref(block_cb);
+	return 0;
+
+err_cb_register:
+	ocelot_port_block_destroy(port_block);
+
+	return ret;
+}
+
+void ocelot_setup_tc_block_flower_unbind(struct ocelot_port *port,
+					 struct tc_block_offload *f)
+{
+	struct ocelot_port_block *port_block;
+	struct tcf_block_cb *block_cb;
+
+	block_cb = tcf_block_cb_lookup(f->block,
+				       ocelot_setup_tc_block_cb_flower, port);
+	if (!block_cb)
+		return;
+
+	port_block = tcf_block_cb_priv(block_cb);
+	if (!tcf_block_cb_decref(block_cb)) {
+		tcf_block_cb_unregister(f->block,
+					ocelot_setup_tc_block_cb_flower, port);
+		ocelot_port_block_destroy(port_block);
+	}
+}