[PATCH 2/7] net/iavf: fix VLAN tag placement logic

[Bruce Richardson]

Depending on what is reported by the PF to the VF the VLAN tag or VLAN +
QinQ tags can be in either the L2Tag1 or the L2Tag2 fields. This needs
to be taken into account when reading the vlan tags from the flex
descriptors, rather than assuming that the tag is always present in a
fixed location.

Fixes: 1e728b01120c ("net/iavf: rework Tx path")
Cc: stable at dpdk.org

Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
---
 drivers/net/intel/iavf/iavf_rxtx.c | 49 +++++++++++++++---------------
 1 file changed, 24 insertions(+), 25 deletions(-)

diff --git a/drivers/net/intel/iavf/iavf_rxtx.c b/drivers/net/intel/iavf/iavf_rxtx.c
index d65a518f8e..39bcbebf56 100644
--- a/drivers/net/intel/iavf/iavf_rxtx.c
+++ b/drivers/net/intel/iavf/iavf_rxtx.c
@@ -1151,33 +1151,32 @@ iavf_rxd_to_vlan_tci(struct rte_mbuf *mb, volatile union ci_rx_desc *rxdp)

 static inline void
 iavf_flex_rxd_to_vlan_tci(struct rte_mbuf *mb,
-			  volatile union ci_rx_flex_desc *rxdp)
+			  volatile union ci_rx_flex_desc *rxdp,
+			  uint8_t rx_flags)
 {
-	if (rte_le_to_cpu_64(rxdp->wb.status_error0) &
-		(1 << IAVF_RX_FLEX_DESC_STATUS0_L2TAG1P_S)) {
-		mb->ol_flags |= RTE_MBUF_F_RX_VLAN |
-				RTE_MBUF_F_RX_VLAN_STRIPPED;
-		mb->vlan_tci =
-			rte_le_to_cpu_16(rxdp->wb.l2tag1);
-	} else {
-		mb->vlan_tci = 0;
-	}
-
-	if (rte_le_to_cpu_16(rxdp->wb.status_error1) &
-	    (1 << IAVF_RX_FLEX_DESC_STATUS1_L2TAG2P_S)) {
-		if ((mb->ol_flags & RTE_MBUF_F_RX_VLAN_STRIPPED) == 0) {
-			mb->ol_flags |= RTE_MBUF_F_RX_VLAN | RTE_MBUF_F_RX_VLAN_STRIPPED;
+	bool l2tag1_valid = rte_le_to_cpu_16(rxdp->wb.status_error0) &
+			(1 << IAVF_RX_FLEX_DESC_STATUS0_L2TAG1P_S);
+	bool l2tag2_valid = rte_le_to_cpu_16(rxdp->wb.status_error1) &
+			(1 << IAVF_RX_FLEX_DESC_STATUS1_L2TAG2P_S);
+	if (l2tag1_valid && l2tag2_valid) {
+		mb->ol_flags |= RTE_MBUF_F_RX_VLAN | RTE_MBUF_F_RX_VLAN_STRIPPED |
+				RTE_MBUF_F_RX_QINQ | RTE_MBUF_F_RX_QINQ_STRIPPED;
+		/* with both tags, the rx_flags say which is outer vs inner */
+		if (rx_flags & IAVF_RX_FLAGS_VLAN_TAG_LOC_L2TAG2_2) {
+			mb->vlan_tci_outer = rte_le_to_cpu_16(rxdp->wb.l2tag2_2nd);
+			mb->vlan_tci = rte_le_to_cpu_16(rxdp->wb.l2tag1);
 		} else {
-			/* if two tags, move Tag1 to outer tag field */
-			mb->ol_flags |= RTE_MBUF_F_RX_QINQ_STRIPPED | RTE_MBUF_F_RX_QINQ;
-			mb->vlan_tci_outer = mb->vlan_tci;
+			mb->vlan_tci_outer = rte_le_to_cpu_16(rxdp->wb.l2tag1);
+			mb->vlan_tci = rte_le_to_cpu_16(rxdp->wb.l2tag2_2nd);
 		}
-		mb->vlan_tci = rte_le_to_cpu_16(rxdp->wb.l2tag2_2nd);
-		PMD_RX_LOG(DEBUG, "Descriptor l2tag2_1: %u, l2tag2_2: %u",
-			   rte_le_to_cpu_16(rxdp->wb.l2tag2_1st),
-			   rte_le_to_cpu_16(rxdp->wb.l2tag2_2nd));
+	} else if (l2tag1_valid || l2tag2_valid) {
+		mb->ol_flags |= RTE_MBUF_F_RX_VLAN | RTE_MBUF_F_RX_VLAN_STRIPPED;
+		mb->vlan_tci_outer = 0;
+		mb->vlan_tci = rte_le_to_cpu_16(
+				l2tag1_valid ? rxdp->wb.l2tag1 : rxdp->wb.l2tag2_2nd);
 	} else {
 		mb->vlan_tci_outer = 0;
+		mb->vlan_tci = 0;
 	}
 }

@@ -1564,7 +1563,7 @@ iavf_recv_pkts_flex_rxd(void *rx_queue,
 		rxm->ol_flags = 0;
 		rxm->packet_type = ptype_tbl[IAVF_RX_FLEX_DESC_PTYPE_M &
 			rte_le_to_cpu_16(rxd.wb.ptype_flex_flags0)];
-		iavf_flex_rxd_to_vlan_tci(rxm, &rxd);
+		iavf_flex_rxd_to_vlan_tci(rxm, &rxd, rxq->rx_flags);
 		iavf_flex_rxd_to_ipsec_crypto_status(rxm, &rxd,
 				&rxq->stats->ipsec_crypto);
 		rxd_to_pkt_fields_ops[rxq->rxdid](rxq, rxm, &rxd);
@@ -1731,7 +1730,7 @@ iavf_recv_scattered_pkts_flex_rxd(void *rx_queue, struct rte_mbuf **rx_pkts,
 		first_seg->ol_flags = 0;
 		first_seg->packet_type = ptype_tbl[IAVF_RX_FLEX_DESC_PTYPE_M &
 			rte_le_to_cpu_16(rxd.wb.ptype_flex_flags0)];
-		iavf_flex_rxd_to_vlan_tci(first_seg, &rxd);
+		iavf_flex_rxd_to_vlan_tci(first_seg, &rxd, rxq->rx_flags);
 		iavf_flex_rxd_to_ipsec_crypto_status(first_seg, &rxd,
 				&rxq->stats->ipsec_crypto);
 		rxd_to_pkt_fields_ops[rxq->rxdid](rxq, first_seg, &rxd);
@@ -2013,7 +2012,7 @@ iavf_rx_scan_hw_ring_flex_rxd(struct ci_rx_queue *rxq,

 			mb->packet_type = ptype_tbl[IAVF_RX_FLEX_DESC_PTYPE_M &
 				rte_le_to_cpu_16(rxdp[j].wb.ptype_flex_flags0)];
-			iavf_flex_rxd_to_vlan_tci(mb, &rxdp[j]);
+			iavf_flex_rxd_to_vlan_tci(mb, &rxdp[j], rxq->rx_flags);
 			iavf_flex_rxd_to_ipsec_crypto_status(mb, &rxdp[j],
 				&rxq->stats->ipsec_crypto);
 			rxd_to_pkt_fields_ops[rxq->rxdid](rxq, mb, &rxdp[j]);
--
2.53.0