flow_offload: reject offload for all drivers with invalid police parameters

As more police parameters are passed to flow_offload, driver can check
them to make sure hardware handles packets in the way indicated by tc.
The conform-exceed control should be drop/pipe or drop/ok. Besides,
for drop/ok, the police should be the last action. As hardware can't
configure peakrate/avrate/overhead, offload should not be supported if
any of them is configured.

Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 49 insertions, 10 deletions

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_matchall.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_matchall.c
index 28fd2de9e4cf..1672d3afe5be 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_matchall.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_matchall.c
@@ -8,6 +8,46 @@
 #include "cxgb4_filter.h"
 #include "cxgb4_tc_flower.h"
 
+static int cxgb4_policer_validate(const struct flow_action *action,
+				  const struct flow_action_entry *act,
+				  struct netlink_ext_ack *extack)
+{
+	if (act->police.exceed.act_id != FLOW_ACTION_DROP) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Offload not supported when exceed action is not drop");
+		return -EOPNOTSUPP;
+	}
+
+	if (act->police.notexceed.act_id != FLOW_ACTION_PIPE &&
+	    act->police.notexceed.act_id != FLOW_ACTION_ACCEPT) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Offload not supported when conform action is not pipe or ok");
+		return -EOPNOTSUPP;
+	}
+
+	if (act->police.notexceed.act_id == FLOW_ACTION_ACCEPT &&
+	    !flow_action_is_last_entry(action, act)) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Offload not supported when conform action is ok, but action is not last");
+		return -EOPNOTSUPP;
+	}
+
+	if (act->police.peakrate_bytes_ps ||
+	    act->police.avrate || act->police.overhead) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Offload not supported when peakrate/avrate/overhead is configured");
+		return -EOPNOTSUPP;
+	}
+
+	if (act->police.rate_pkt_ps) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "QoS offload not support packets per second");
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
 static int cxgb4_matchall_egress_validate(struct net_device *dev,
 					  struct tc_cls_matchall_offload *cls)
 {
@@ -48,11 +88,10 @@ static int cxgb4_matchall_egress_validate(struct net_device *dev,
 	flow_action_for_each(i, entry, actions) {
 		switch (entry->id) {
 		case FLOW_ACTION_POLICE:
-			if (entry->police.rate_pkt_ps) {
-				NL_SET_ERR_MSG_MOD(extack,
-						   "QoS offload not support packets per second");
-				return -EOPNOTSUPP;
-			}
+			ret = cxgb4_policer_validate(actions, entry, extack);
+			if (ret)
+				return ret;
+
 			/* Convert bytes per second to bits per second */
 			if (entry->police.rate_bytes_ps * 8 > max_link_rate) {
 				NL_SET_ERR_MSG_MOD(extack,
@@ -150,11 +189,11 @@ static int cxgb4_matchall_alloc_tc(struct net_device *dev,
 	flow_action_for_each(i, entry, &cls->rule->action)
 		if (entry->id == FLOW_ACTION_POLICE)
 			break;
-	if (entry->police.rate_pkt_ps) {
-		NL_SET_ERR_MSG_MOD(extack,
-				   "QoS offload not support packets per second");
-		return -EOPNOTSUPP;
-	}
+
+	ret = cxgb4_policer_validate(&cls->rule->action, entry, extack);
+	if (ret)
+		return ret;
+
 	/* Convert from bytes per second to Kbps */
 	p.u.params.maxrate = div_u64(entry->police.rate_bytes_ps * 8, 1000);
 	p.u.params.channel = pi->tx_chan;