ice: Fix transmit for all software offloaded VLANs

Currently the driver does not recognize when there is an 802.1AD VLAN
tag right after the dmac/smac (outermost VLAN tag). If any DCB map is
applied and/or DCB is enabled this is causing the hardware to insert a
VLAN 0 tag after the 802.1AD VLAN tag that is already in the packet.
Fix this by preventing VLAN tag 0 from being added when any VLAN is
already present after dmac/smac (software offloaded) or skb (hardware
offloaded).

Signed-off-by: Brett Creeley <[email protected]>
Tested-by: Andrew Bowers <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>

1 files changed, 9 insertions, 34 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
index cda7e05bd8ae..abdb137c8bb7 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
@@ -2053,49 +2053,25 @@ int ice_tx_csum(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
  *
  * Checks the skb and set up correspondingly several generic transmit flags
  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
- *
- * Returns error code indicate the frame should be dropped upon error and the
- * otherwise returns 0 to indicate the flags has been set properly.
  */
-static int
+static void
 ice_tx_prepare_vlan_flags(struct ice_ring *tx_ring, struct ice_tx_buf *first)
 {
 	struct sk_buff *skb = first->skb;
-	__be16 protocol = skb->protocol;
 
-	if (protocol == htons(ETH_P_8021Q) &&
-	    !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
-		/* when HW VLAN acceleration is turned off by the user the
-		 * stack sets the protocol to 8021q so that the driver
-		 * can take any steps required to support the SW only
-		 * VLAN handling. In our case the driver doesn't need
-		 * to take any further steps so just set the protocol
-		 * to the encapsulated ethertype.
-		 */
-		skb->protocol = vlan_get_protocol(skb);
-		return 0;
-	}
+	/* nothing left to do, software offloaded VLAN */
+	if (!skb_vlan_tag_present(skb) && eth_type_vlan(skb->protocol))
+		return;
 
-	/* if we have a HW VLAN tag being added, default to the HW one */
+	/* currently, we always assume 802.1Q for VLAN insertion as VLAN
+	 * insertion for 802.1AD is not supported
+	 */
 	if (skb_vlan_tag_present(skb)) {
 		first->tx_flags |= skb_vlan_tag_get(skb) << ICE_TX_FLAGS_VLAN_S;
 		first->tx_flags |= ICE_TX_FLAGS_HW_VLAN;
-	} else if (protocol == htons(ETH_P_8021Q)) {
-		struct vlan_hdr *vhdr, _vhdr;
-
-		/* for SW VLAN, check the next protocol and store the tag */
-		vhdr = (struct vlan_hdr *)skb_header_pointer(skb, ETH_HLEN,
-							     sizeof(_vhdr),
-							     &_vhdr);
-		if (!vhdr)
-			return -EINVAL;
-
-		first->tx_flags |= ntohs(vhdr->h_vlan_TCI) <<
-				   ICE_TX_FLAGS_VLAN_S;
-		first->tx_flags |= ICE_TX_FLAGS_SW_VLAN;
 	}
 
-	return ice_tx_prepare_vlan_flags_dcb(tx_ring, first);
+	ice_tx_prepare_vlan_flags_dcb(tx_ring, first);
 }
 
 /**
@@ -2403,8 +2379,7 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_ring *tx_ring)
 	first->tx_flags = 0;
 
 	/* prepare the VLAN tagging flags for Tx */
-	if (ice_tx_prepare_vlan_flags(tx_ring, first))
-		goto out_drop;
+	ice_tx_prepare_vlan_flags(tx_ring, first);
 
 	/* set up TSO offload */
 	tso = ice_tso(first, &offload);