[PATCH net-next v2 3/3] net: ethernet: ti: cpsw_new: enable bc/mc storm prevention support

Grygorii Strashko
2021-11-01T17:01:58Z

This patch enables support for ingress broadcast(BC)/multicast(MC) packets
rate limiting in TI CPSW switchdev driver (the corresponding ALE support
was added in previous patch) by implementing HW offload for simple
tc-flower with policer action with matches on dst_mac:
- ff:ff:ff:ff:ff:ff has to be used for BC packets rate limiting (exact
match)
- 01:00:00:00:00:00 fixed value has to be used for MC packets rate
limiting (exact match)

The CPSW supports MC/BC packets rate limiting in packets/sec and affects
all ingress MC/BC packets and serves as BC/MC storm prevention feature.

Examples:
- BC rate limit to 1000pps:
tc qdisc add dev eth0 clsact
tc filter add dev eth0 ingress flower skip_sw dst_mac ff:ff:ff:ff:ff:ff \
action police pkts_rate 1000 pkts_burst 1

- MC rate limit to 20000pps:
tc qdisc add dev eth0 clsact
tc filter add dev eth0 ingress flower skip_sw dst_mac 01:00:00:00:00:00 \
action police pkts_rate 10000 pkts_burst 1

pkts_burst - not used.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
drivers/net/ethernet/ti/cpsw_new.c | 4 +-
drivers/net/ethernet/ti/cpsw_priv.c | 170 ++++++++++++++++++++++++++++
drivers/net/ethernet/ti/cpsw_priv.h | 8 ++
3 files changed, 181 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ti/cpsw_new.c b/drivers/net/ethernet/ti/cpsw_new.c
index 279e261e4720..662c46d568f9 100644
--- a/drivers/net/ethernet/ti/cpsw_new.c
+++ b/drivers/net/ethernet/ti/cpsw_new.c
@@ -498,6 +498,8 @@ static void cpsw_restore(struct cpsw_priv *priv)

/* restore CBS offload */
cpsw_cbs_resume(&cpsw->slaves[priv->emac_port - 1], priv);
+
+ cpsw_qos_clsflower_resume(priv);
}

static void cpsw_init_stp_ale_entry(struct cpsw_common *cpsw)
@@ -1407,7 +1409,7 @@ static int cpsw_create_ports(struct cpsw_common *cpsw)
cpsw->slaves[i].ndev = ndev;

ndev->features |= NETIF_F_HW_VLAN_CTAG_FILTER |
- NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_NETNS_LOCAL;
+ NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_NETNS_LOCAL | NETIF_F_HW_TC;

ndev->netdev_ops = &cpsw_netdev_ops;
ndev->ethtool_ops = &cpsw_ethtool_ops;
diff --git a/drivers/net/ethernet/ti/cpsw_priv.c b/drivers/net/ethernet/ti/cpsw_priv.c
index ecc2a6b7e28f..aea79a18e976 100644
--- a/drivers/net/ethernet/ti/cpsw_priv.c
+++ b/drivers/net/ethernet/ti/cpsw_priv.c
@@ -502,6 +502,7 @@ int cpsw_init_common(struct cpsw_common *cpsw, void __iomem *ss_regs,
ale_params.ale_ageout = ale_ageout;
ale_params.ale_ports = CPSW_ALE_PORTS_NUM;
ale_params.dev_id = "cpsw";
+ ale_params.bus_freq = cpsw->bus_freq_mhz * 1000000;

cpsw->ale = cpsw_ale_create(&ale_params);
if (IS_ERR(cpsw->ale)) {
@@ -1046,6 +1047,8 @@ static int cpsw_set_mqprio(struct net_device *ndev, void *type_data)
return 0;
}

+static int cpsw_qos_setup_tc_block(struct net_device *ndev, struct flow_block_offload *f);
+
int cpsw_ndo_setup_tc(struct net_device *ndev, enum tc_setup_type type,
void *type_data)
{
@@ -1056,6 +1059,9 @@ int cpsw_ndo_setup_tc(struct net_device *ndev, enum tc_setup_type type,
case TC_SETUP_QDISC_MQPRIO:
return cpsw_set_mqprio(ndev, type_data);

+ case TC_SETUP_BLOCK:
+ return cpsw_qos_setup_tc_block(ndev, type_data);
+
default:
return -EOPNOTSUPP;
}
@@ -1379,3 +1385,167 @@ int cpsw_run_xdp(struct cpsw_priv *priv, int ch, struct xdp_buff *xdp,
page_pool_recycle_direct(cpsw->page_pool[ch], page);
return ret;
}
+
+static int cpsw_qos_clsflower_add_policer(struct cpsw_priv *priv,
+ struct netlink_ext_ack *extack,
+ struct flow_cls_offload *cls,
+ u64 rate_pkt_ps)
+{
+ struct flow_rule *rule = flow_cls_offload_flow_rule(cls);
+ struct flow_dissector *dissector = rule->match.dissector;
+ u8 mc_mac[] = {0x01, 0x00, 0x00, 0x00, 0x00, 0x00};
+ struct flow_match_eth_addrs match;
+ u32 port_id;
+ int ret;
+
+ if (dissector->used_keys &
+ ~(BIT(FLOW_DISSECTOR_KEY_BASIC) |
+ BIT(FLOW_DISSECTOR_KEY_CONTROL) |
+ BIT(FLOW_DISSECTOR_KEY_ETH_ADDRS))) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Unsupported keys used");
+ return -EOPNOTSUPP;
+ }
+
+ if (!flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
+ NL_SET_ERR_MSG_MOD(extack, "Not matching on eth address");
+ return -EOPNOTSUPP;
+ }
+
+ flow_rule_match_eth_addrs(rule, &match);
+
+ if (!is_zero_ether_addr(match.key->src)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Matching on source MAC not supported");
+ return -EOPNOTSUPP;
+ }
+
+ port_id = cpsw_slave_index(priv->cpsw, priv) + 1;
+
+ if (is_broadcast_ether_addr(match.key->dst)) {
+ ret = cpsw_ale_rx_ratelimit_bc(priv->cpsw->ale, port_id, rate_pkt_ps);
+ if (ret)
+ return ret;
+
+ priv->ale_bc_ratelimit.cookie = cls->cookie;
+ priv->ale_bc_ratelimit.rate_packet_ps = rate_pkt_ps;
+ }
+
+ if (ether_addr_equal(match.key->dst, mc_mac)) {
+ ret = cpsw_ale_rx_ratelimit_mc(priv->cpsw->ale, port_id, rate_pkt_ps);
+ if (ret)
+ return ret;
+
+ priv->ale_mc_ratelimit.cookie = cls->cookie;
+ priv->ale_mc_ratelimit.rate_packet_ps = rate_pkt_ps;
+ }
+
+ return 0;
+}
+
+static int cpsw_qos_configure_clsflower(struct cpsw_priv *priv, struct flow_cls_offload *cls)
+{
+ struct flow_rule *rule = flow_cls_offload_flow_rule(cls);
+ struct netlink_ext_ack *extack = cls->common.extack;
+ const struct flow_action_entry *act;
+ int i;
+
+ flow_action_for_each(i, act, &rule->action) {
+ switch (act->id) {
+ case FLOW_ACTION_POLICE:
+ if (act->police.rate_bytes_ps) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "QoS offload not support bytes per second");
+ return -EOPNOTSUPP;
+ }
+
+ return cpsw_qos_clsflower_add_policer(priv, extack, cls,
+ act->police.rate_pkt_ps);
+ default:
+ NL_SET_ERR_MSG_MOD(extack, "Action not supported");
+ return -EOPNOTSUPP;
+ }
+ }
+ return -EOPNOTSUPP;
+}
+
+static int cpsw_qos_delete_clsflower(struct cpsw_priv *priv, struct flow_cls_offload *cls)
+{
+ u32 port_id = cpsw_slave_index(priv->cpsw, priv) + 1;
+
+ if (cls->cookie == priv->ale_bc_ratelimit.cookie) {
+ priv->ale_bc_ratelimit.cookie = 0;
+ priv->ale_bc_ratelimit.rate_packet_ps = 0;
+ cpsw_ale_rx_ratelimit_bc(priv->cpsw->ale, port_id, 0);
+ }
+
+ if (cls->cookie == priv->ale_mc_ratelimit.cookie) {
+ priv->ale_mc_ratelimit.cookie = 0;
+ priv->ale_mc_ratelimit.rate_packet_ps = 0;
+ cpsw_ale_rx_ratelimit_mc(priv->cpsw->ale, port_id, 0);
+ }
+
+ return 0;
+}
+
+static int cpsw_qos_setup_tc_clsflower(struct cpsw_priv *priv, struct flow_cls_offload *cls_flower)
+{
+ switch (cls_flower->command) {
+ case FLOW_CLS_REPLACE:
+ return cpsw_qos_configure_clsflower(priv, cls_flower);
+ case FLOW_CLS_DESTROY:
+ return cpsw_qos_delete_clsflower(priv, cls_flower);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int cpsw_qos_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void *cb_priv)
+{
+ struct cpsw_priv *priv = cb_priv;
+ int ret;
+
+ if (!tc_cls_can_offload_and_chain0(priv->ndev, type_data))
+ return -EOPNOTSUPP;
+
+ ret = pm_runtime_get_sync(priv->dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(priv->dev);
+ return ret;
+ }
+
+ switch (type) {
+ case TC_SETUP_CLSFLOWER:
+ ret = cpsw_qos_setup_tc_clsflower(priv, type_data);
+ break;
+ default:
+ ret = -EOPNOTSUPP;
+ }
+
+ pm_runtime_put(priv->dev);
+ return ret;
+}
+
+static LIST_HEAD(cpsw_qos_block_cb_list);
+
+static int cpsw_qos_setup_tc_block(struct net_device *ndev, struct flow_block_offload *f)
+{
+ struct cpsw_priv *priv = netdev_priv(ndev);
+
+ return flow_block_cb_setup_simple(f, &cpsw_qos_block_cb_list,
+ cpsw_qos_setup_tc_block_cb,
+ priv, priv, true);
+}
+
+void cpsw_qos_clsflower_resume(struct cpsw_priv *priv)
+{
+ u32 port_id = cpsw_slave_index(priv->cpsw, priv) + 1;
+
+ if (priv->ale_bc_ratelimit.cookie)
+ cpsw_ale_rx_ratelimit_bc(priv->cpsw->ale, port_id,
+ priv->ale_bc_ratelimit.rate_packet_ps);
+
+ if (priv->ale_mc_ratelimit.cookie)
+ cpsw_ale_rx_ratelimit_mc(priv->cpsw->ale, port_id,
+ priv->ale_mc_ratelimit.rate_packet_ps);
+}
diff --git a/drivers/net/ethernet/ti/cpsw_priv.h b/drivers/net/ethernet/ti/cpsw_priv.h
index 435668ee542d..595a5e97af69 100644
--- a/drivers/net/ethernet/ti/cpsw_priv.h
+++ b/drivers/net/ethernet/ti/cpsw_priv.h
@@ -362,6 +362,11 @@ struct cpsw_common {
u8 base_mac[ETH_ALEN];
};

+struct cpsw_ale_ratelimit {
+ unsigned long cookie;
+ u64 rate_packet_ps;
+};
+
struct cpsw_priv {
struct net_device *ndev;
struct device *dev;
@@ -382,6 +387,8 @@ struct cpsw_priv {
struct cpsw_common *cpsw;
int offload_fwd_mark;
u32 tx_packet_min;
+ struct cpsw_ale_ratelimit ale_bc_ratelimit;
+ struct cpsw_ale_ratelimit ale_mc_ratelimit;
};

#define ndev_to_cpsw(ndev) (((struct cpsw_priv *)netdev_priv(ndev))->cpsw)
@@ -460,6 +467,7 @@ int cpsw_ndo_setup_tc(struct net_device *ndev, enum tc_setup_type type,
bool cpsw_shp_is_off(struct cpsw_priv *priv);
void cpsw_cbs_resume(struct cpsw_slave *slave, struct cpsw_priv *priv);
void cpsw_mqprio_resume(struct cpsw_slave *slave, struct cpsw_priv *priv);
+void cpsw_qos_clsflower_resume(struct cpsw_priv *priv);

/* ethtool */
u32 cpsw_get_msglevel(struct net_device *ndev);
--
2.17.1