[PATCH v2 6/6] net/iavf: fix QinQ insertion with mbuf flags VLAN and QINQ

[Ciara Loftus]

Fix an issue that would arise in the event an mbuf had both the VLAN and
QINQ insertion offload flags set. In this case the L2TAG2 field would be
written to twice and could cause the tag to be corrupted. Reorder the
logic of populating the L2TAG2 field and ensure that the field is only
written to once.

Fixes: 3aa4efa36438 ("net/iavf: support VLAN insertion in AVX512 Tx")

Signed-off-by: Ciara Loftus <ciara.loftus at intel.com>
---
 drivers/net/intel/iavf/iavf_rxtx_vec_avx512.c | 26 +++++++++----------
 drivers/net/intel/iavf/iavf_rxtx_vec_common.h |  9 +++----
 2 files changed, 15 insertions(+), 20 deletions(-)

diff --git a/drivers/net/intel/iavf/iavf_rxtx_vec_avx512.c b/drivers/net/intel/iavf/iavf_rxtx_vec_avx512.c
index cd067a0199..7c0907b7cf 100644
--- a/drivers/net/intel/iavf/iavf_rxtx_vec_avx512.c
+++ b/drivers/net/intel/iavf/iavf_rxtx_vec_avx512.c
@@ -2136,13 +2136,6 @@ ctx_vtx(volatile struct iavf_tx_desc *txdp,
 
 #ifdef IAVF_TX_VLAN_QINQ_OFFLOAD
 		if (offload) {
-			if (pkt[1]->ol_flags & RTE_MBUF_F_TX_VLAN &&
-					vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG2) {
-				hi_ctx_qw1 |=
-					IAVF_TX_CTX_DESC_IL2TAG2 << IAVF_TXD_CTX_QW1_CMD_SHIFT;
-				low_ctx_qw1 |=
-					(uint64_t)pkt[1]->vlan_tci << IAVF_TXD_CTX_QW0_L2TAG2_PARAM;
-			}
 			if (pkt[1]->ol_flags & RTE_MBUF_F_TX_QINQ) {
 				uint64_t qinq_tag = vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG2 ?
 					(uint64_t)pkt[1]->vlan_tci :
@@ -2150,6 +2143,12 @@ ctx_vtx(volatile struct iavf_tx_desc *txdp,
 				hi_ctx_qw1 |= IAVF_TX_CTX_DESC_IL2TAG2 <<
 						IAVF_TXD_CTX_QW1_CMD_SHIFT;
 				low_ctx_qw1 |= qinq_tag << IAVF_TXD_CTX_QW0_L2TAG2_PARAM;
+			} else if (pkt[1]->ol_flags & RTE_MBUF_F_TX_VLAN &&
+					vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG2) {
+				hi_ctx_qw1 |=
+					IAVF_TX_CTX_DESC_IL2TAG2 << IAVF_TXD_CTX_QW1_CMD_SHIFT;
+				low_ctx_qw1 |=
+					(uint64_t)pkt[1]->vlan_tci << IAVF_TXD_CTX_QW0_L2TAG2_PARAM;
 			}
 		}
 #endif
@@ -2159,13 +2158,6 @@ ctx_vtx(volatile struct iavf_tx_desc *txdp,
 
 #ifdef IAVF_TX_VLAN_QINQ_OFFLOAD
 		if (offload) {
-			if (pkt[0]->ol_flags & RTE_MBUF_F_TX_VLAN &&
-					vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG2) {
-				hi_ctx_qw0 |=
-					IAVF_TX_CTX_DESC_IL2TAG2 << IAVF_TXD_CTX_QW1_CMD_SHIFT;
-				low_ctx_qw0 |=
-					(uint64_t)pkt[0]->vlan_tci << IAVF_TXD_CTX_QW0_L2TAG2_PARAM;
-			}
 			if (pkt[0]->ol_flags & RTE_MBUF_F_TX_QINQ) {
 				uint64_t qinq_tag = vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG2 ?
 					(uint64_t)pkt[0]->vlan_tci :
@@ -2173,6 +2165,12 @@ ctx_vtx(volatile struct iavf_tx_desc *txdp,
 				hi_ctx_qw0 |= IAVF_TX_CTX_DESC_IL2TAG2 <<
 						IAVF_TXD_CTX_QW1_CMD_SHIFT;
 				low_ctx_qw0 |= qinq_tag << IAVF_TXD_CTX_QW0_L2TAG2_PARAM;
+			} else if (pkt[0]->ol_flags & RTE_MBUF_F_TX_VLAN &&
+					vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG2) {
+				hi_ctx_qw0 |=
+					IAVF_TX_CTX_DESC_IL2TAG2 << IAVF_TXD_CTX_QW1_CMD_SHIFT;
+				low_ctx_qw0 |=
+					(uint64_t)pkt[0]->vlan_tci << IAVF_TXD_CTX_QW0_L2TAG2_PARAM;
 			}
 		}
 #endif
diff --git a/drivers/net/intel/iavf/iavf_rxtx_vec_common.h b/drivers/net/intel/iavf/iavf_rxtx_vec_common.h
index 36150f0f65..d98fb9fe29 100644
--- a/drivers/net/intel/iavf/iavf_rxtx_vec_common.h
+++ b/drivers/net/intel/iavf/iavf_rxtx_vec_common.h
@@ -230,12 +230,6 @@ iavf_txd_enable_offload(__rte_unused struct rte_mbuf *tx_pkt,
 #endif
 
 #ifdef IAVF_TX_VLAN_QINQ_OFFLOAD
-	if (ol_flags & RTE_MBUF_F_TX_VLAN && vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG1) {
-		td_cmd |= IAVF_TX_DESC_CMD_IL2TAG1;
-		*txd_hi |= ((uint64_t)tx_pkt->vlan_tci <<
-			    IAVF_TXD_QW1_L2TAG1_SHIFT);
-	}
-
 	if (ol_flags & RTE_MBUF_F_TX_QINQ) {
 		td_cmd |= IAVF_TX_DESC_CMD_IL2TAG1;
 		/* vlan_flag specifies outer tag location for QinQ. */
@@ -245,6 +239,9 @@ iavf_txd_enable_offload(__rte_unused struct rte_mbuf *tx_pkt,
 		else
 			*txd_hi |= ((uint64_t)tx_pkt->vlan_tci <<
 					IAVF_TXD_QW1_L2TAG1_SHIFT);
+	} else if (ol_flags & RTE_MBUF_F_TX_VLAN && vlan_flag & IAVF_TX_FLAGS_VLAN_TAG_LOC_L2TAG1) {
+		td_cmd |= IAVF_TX_DESC_CMD_IL2TAG1;
+		*txd_hi |= ((uint64_t)tx_pkt->vlan_tci << IAVF_TXD_QW1_L2TAG1_SHIFT);
 	}
 #endif
 
-- 
2.34.1