bnx2x: Allow vfs to disable txvlan offload

VF clients are configured as enforced, meaning firmware is validating
the correctness of their ethertype/vid during transmission.
Once txvlan is disabled, VF would start getting SKBs for transmission
here vlan is on the payload - but it'll pass the packet's ethertype
instead of the vid, leading to firmware declaring it as malicious.
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c

@@ -3883,15 +3883,26 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		/* when transmitting in a vf, start bd must hold the ethertype
 		 * for fw to enforce it
 		 */
+		u16 vlan_tci = 0;
 #ifndef BNX2X_STOP_ON_ERROR
-		if (IS_VF(bp))
+		if (IS_VF(bp)) {
 #endif
-			tx_start_bd->vlan_or_ethertype =
-				cpu_to_le16(ntohs(eth->h_proto));
+			/* Still need to consider inband vlan for enforced */
+			if (__vlan_get_tag(skb, &vlan_tci)) {
+				tx_start_bd->vlan_or_ethertype =
+					cpu_to_le16(ntohs(eth->h_proto));
+			} else {
+				tx_start_bd->bd_flags.as_bitfield |=
+					(X_ETH_INBAND_VLAN <<
+					 ETH_TX_BD_FLAGS_VLAN_MODE_SHIFT);
+				tx_start_bd->vlan_or_ethertype =
+					cpu_to_le16(vlan_tci);
+			}
 #ifndef BNX2X_STOP_ON_ERROR
-		else
+		} else {
 			/* used by FW for packet accounting */
 			tx_start_bd->vlan_or_ethertype = cpu_to_le16(pkt_prod);
+		}
 #endif
 	}