octeontx2-pf: Add additional check for MCAM rules

Due to hardware limitation, MCAM drop rule with
ether_type == 802.1Q and vlan_id == 0 is not supported. Hence rejecting
such rules.

Fixes: dce677d ("octeontx2-pf: Add vlan-etype to ntuple filters")
Signed-off-by: Suman Ghosh <sumang@marvell.com>
Link: https://lore.kernel.org/r/20230710103027.2244139-1-sumang@marvell.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: sumang-mrvl

drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c

@@ -872,6 +872,14 @@ static int otx2_prepare_flow_request(struct ethtool_rx_flow_spec *fsp,
 				return -EINVAL;
 
 			vlan_etype = be16_to_cpu(fsp->h_ext.vlan_etype);
+
+			/* Drop rule with vlan_etype == 802.1Q
+			 * and vlan_id == 0 is not supported
+			 */
+			if (vlan_etype == ETH_P_8021Q && !fsp->m_ext.vlan_tci &&
+			    fsp->ring_cookie == RX_CLS_FLOW_DISC)
+				return -EINVAL;
+
 			/* Only ETH_P_8021Q and ETH_P_802AD types supported */
 			if (vlan_etype != ETH_P_8021Q &&
 			    vlan_etype != ETH_P_8021AD)

drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c

@@ -597,6 +597,21 @@ static int otx2_tc_prepare_flow(struct otx2_nic *nic, struct otx2_tc_flow *node,
 			return -EOPNOTSUPP;
 		}
 
+		if (!match.mask->vlan_id) {
+			struct flow_action_entry *act;
+			int i;
+
+			flow_action_for_each(i, act, &rule->action) {
+				if (act->id == FLOW_ACTION_DROP) {
+					netdev_err(nic->netdev,
+						   "vlan tpid 0x%x with vlan_id %d is not supported for DROP rule.\n",
+						   ntohs(match.key->vlan_tpid),
+						   match.key->vlan_id);
+					return -EOPNOTSUPP;
+				}
+			}
+		}
+
 		if (match.mask->vlan_id ||
 		    match.mask->vlan_dei ||
 		    match.mask->vlan_priority) {