net: iflib: fix vlan processing in the drivers

The logic that sets iri_vtag and M_VLANTAG does not handle the
case where the 802.11q VLAN tag is 0. Fix this issue across
the iflib drivers. While there, also improve and align the
VLAN tag check extraction, by moving it outside the RX descriptor
loop, eliminating a local variable and additional checks.

PR:             260068
Reviewed by:    kbowling, gallatin
Reported by:	erj
MFC after:      1 month
Differential Revision:  https://reviews.freebsd.org/D33156

7 files changed, 36 insertions, 58 deletions

diff --git a/sys/dev/e1000/em_txrx.c b/sys/dev/e1000/em_txrx.c
index 58f9345ea19d..aebafca73cca 100644
--- a/sys/dev/e1000/em_txrx.c
+++ b/sys/dev/e1000/em_txrx.c
@@ -671,9 +671,9 @@ em_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	u32 pkt_info;
 	u32 staterr = 0;
 	bool eop;
-	int i, cidx, vtag;
+	int i, cidx;
 
-	i = vtag = 0;
+	i = 0;
 	cidx = ri->iri_cidx;
 
 	do {
@@ -710,12 +710,9 @@ em_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 		em_receive_checksum(staterr, staterr >> 24, ri);
 
 	if (staterr & E1000_RXD_STAT_VP) {
-		vtag = le16toh(rxd->wb.upper.vlan);
-	}
-
-	ri->iri_vtag = vtag;
-	if (vtag)
+		ri->iri_vtag = le16toh(rxd->wb.upper.vlan);
 		ri->iri_flags |= M_VLANTAG;
+	}
 
 	ri->iri_flowid = le32toh(rxd->wb.lower.hi_dword.rss);
 	ri->iri_rsstype = em_determine_rsstype(pkt_info);
diff --git a/sys/dev/e1000/igb_txrx.c b/sys/dev/e1000/igb_txrx.c
index 548ceee8ab46..1c1500e78d19 100644
--- a/sys/dev/e1000/igb_txrx.c
+++ b/sys/dev/e1000/igb_txrx.c
@@ -436,12 +436,12 @@ igb_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	struct rx_ring *rxr = &que->rxr;
 	union e1000_adv_rx_desc *rxd;
 
-	uint16_t pkt_info, len, vtag;
+	uint16_t pkt_info, len;
 	uint32_t ptype, staterr;
 	int i, cidx;
 	bool eop;
 
-	staterr = i = vtag = 0;
+	staterr = i = 0;
 	cidx = ri->iri_cidx;
 
 	do {
@@ -460,13 +460,6 @@ igb_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 		rxd->wb.upper.status_error = 0;
 		eop = ((staterr & E1000_RXD_STAT_EOP) == E1000_RXD_STAT_EOP);
 
-		if (((sc->hw.mac.type == e1000_i350) ||
-		    (sc->hw.mac.type == e1000_i354)) &&
-		    (staterr & E1000_RXDEXT_STATERR_LB))
-			vtag = be16toh(rxd->wb.upper.vlan);
-		else
-			vtag = le16toh(rxd->wb.upper.vlan);
-
 		/* Make sure bad packets are discarded */
 		if (eop && ((staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) != 0)) {
 			sc->dropped_pkts++;
@@ -495,9 +488,13 @@ igb_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	if ((scctx->isc_capenable & IFCAP_RXCSUM) != 0)
 		igb_rx_checksum(staterr, ri, ptype);
 
-	if ((scctx->isc_capenable & IFCAP_VLAN_HWTAGGING) != 0 &&
-	    (staterr & E1000_RXD_STAT_VP) != 0) {
-		ri->iri_vtag = vtag;
+	if (staterr & E1000_RXD_STAT_VP) {
+		if (((sc->hw.mac.type == e1000_i350) ||
+		    (sc->hw.mac.type == e1000_i354)) &&
+		    (staterr & E1000_RXDEXT_STATERR_LB))
+			ri->iri_vtag = be16toh(rxd->wb.upper.vlan);
+		else
+			ri->iri_vtag = le16toh(rxd->wb.upper.vlan);
 		ri->iri_flags |= M_VLANTAG;
 	}
 
diff --git a/sys/dev/iavf/iavf_txrx_iflib.c b/sys/dev/iavf/iavf_txrx_iflib.c
index f536f7f23ff5..5f24b9c18452 100644
--- a/sys/dev/iavf/iavf_txrx_iflib.c
+++ b/sys/dev/iavf/iavf_txrx_iflib.c
@@ -670,7 +670,7 @@ iavf_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	struct rx_ring		*rxr = &que->rxr;
 	union iavf_rx_desc	*cur;
 	u32		status, error;
-	u16		plen, vtag;
+	u16		plen;
 	u64		qword;
 	u8		ptype;
 	bool		eop;
@@ -701,10 +701,6 @@ iavf_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 
 		cur->wb.qword1.status_error_len = 0;
 		eop = (status & (1 << IAVF_RX_DESC_STATUS_EOF_SHIFT));
-		if (status & (1 << IAVF_RX_DESC_STATUS_L2TAG1P_SHIFT))
-			vtag = le16toh(cur->wb.qword0.lo_dword.l2tag1);
-		else
-			vtag = 0;
 
 		/*
 		** Make sure bad packets are discarded,
@@ -731,10 +727,11 @@ iavf_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 		iavf_rx_checksum(ri, status, error, ptype);
 	ri->iri_flowid = le32toh(cur->wb.qword0.hi_dword.rss);
 	ri->iri_rsstype = iavf_ptype_to_hash(ptype);
-	ri->iri_vtag = vtag;
-	ri->iri_nfrags = i;
-	if (vtag)
+	if (status & (1 << IAVF_RX_DESC_STATUS_L2TAG1P_SHIFT)) {
+		ri->iri_vtag = le16toh(cur->wb.qword0.lo_dword.l2tag1);
 		ri->iri_flags |= M_VLANTAG;
+	}
+	ri->iri_nfrags = i;
 	return (0);
 }
 
diff --git a/sys/dev/ice/ice_iflib_txrx.c b/sys/dev/ice/ice_iflib_txrx.c
index 7d89c51ddec0..0ce59d96c0ed 100644
--- a/sys/dev/ice/ice_iflib_txrx.c
+++ b/sys/dev/ice/ice_iflib_txrx.c
@@ -285,7 +285,7 @@ ice_ift_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	if_softc_ctx_t scctx = sc->scctx;
 	struct ice_rx_queue *rxq = &sc->pf_vsi.rx_queues[ri->iri_qsidx];
 	union ice_32b_rx_flex_desc *cur;
-	u16 status0, plen, vtag, ptype;
+	u16 status0, plen, ptype;
 	bool eop;
 	size_t cidx;
 	int i;
@@ -310,10 +310,6 @@ ice_ift_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 
 		cur->wb.status_error0 = 0;
 		eop = (status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_EOF_S));
-		if (status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L2TAG1P_S))
-			vtag = le16toh(cur->wb.l2tag1);
-		else
-			vtag = 0;
 
 		/*
 		 * Make sure packets with bad L2 values are discarded.
@@ -340,10 +336,11 @@ ice_ift_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 				&ri->iri_csum_data, status0, ptype);
 	ri->iri_flowid = le32toh(RX_FLEX_NIC(&cur->wb, rss_hash));
 	ri->iri_rsstype = ice_ptype_to_hash(ptype);
-	ri->iri_vtag = vtag;
-	ri->iri_nfrags = i;
-	if (vtag)
+	if (status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L2TAG1P_S)) {
+		ri->iri_vtag = le16toh(cur->wb.l2tag1);
 		ri->iri_flags |= M_VLANTAG;
+	}
+	ri->iri_nfrags = i;
 	return (0);
 }
 
diff --git a/sys/dev/igc/igc_txrx.c b/sys/dev/igc/igc_txrx.c
index ee4d5a5c0c6b..4f8234c855f6 100644
--- a/sys/dev/igc/igc_txrx.c
+++ b/sys/dev/igc/igc_txrx.c
@@ -461,12 +461,12 @@ igc_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	struct rx_ring *rxr = &que->rxr;
 	union igc_adv_rx_desc *rxd;
 
-	uint16_t pkt_info, len, vtag;
+	uint16_t pkt_info, len;
 	uint32_t ptype, staterr;
 	int i, cidx;
 	bool eop;
 
-	staterr = i = vtag = 0;
+	staterr = i = 0;
 	cidx = ri->iri_cidx;
 
 	do {
@@ -485,8 +485,6 @@ igc_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 		rxd->wb.upper.status_error = 0;
 		eop = ((staterr & IGC_RXD_STAT_EOP) == IGC_RXD_STAT_EOP);
 
-		vtag = le16toh(rxd->wb.upper.vlan);
-
 		/* Make sure bad packets are discarded */
 		if (eop && ((staterr & IGC_RXDEXT_STATERR_RXE) != 0)) {
 			adapter->dropped_pkts++;
@@ -517,7 +515,7 @@ igc_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 
 	if ((scctx->isc_capenable & IFCAP_VLAN_HWTAGGING) != 0 &&
 	    (staterr & IGC_RXD_STAT_VP) != 0) {
-		ri->iri_vtag = vtag;
+		ri->iri_vtag = le16toh(rxd->wb.upper.vlan);
 		ri->iri_flags |= M_VLANTAG;
 	}
 
diff --git a/sys/dev/ixgbe/ix_txrx.c b/sys/dev/ixgbe/ix_txrx.c
index 7c87b0ec10fc..589f4c72c9ce 100644
--- a/sys/dev/ixgbe/ix_txrx.c
+++ b/sys/dev/ixgbe/ix_txrx.c
@@ -399,7 +399,6 @@ ixgbe_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	union ixgbe_adv_rx_desc  *rxd;
 
 	uint16_t                  pkt_info, len, cidx, i;
-	uint16_t                  vtag = 0;
 	uint32_t                  ptype;
 	uint32_t                  staterr = 0;
 	bool                      eop;
@@ -424,12 +423,6 @@ ixgbe_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 		rxd->wb.upper.status_error = 0;
 		eop = ((staterr & IXGBE_RXD_STAT_EOP) != 0);
 
-		if ( (rxr->vtag_strip) && (staterr & IXGBE_RXD_STAT_VP) ) {
-			vtag = le16toh(rxd->wb.upper.vlan);
-		} else {
-			vtag = 0;
-		}
-
 		/* Make sure bad packets are discarded */
 		if (eop && (staterr & IXGBE_RXDADV_ERR_FRAME_ERR_MASK) != 0) {
 			if (sc->feat_en & IXGBE_FEATURE_VF)
@@ -463,10 +456,12 @@ ixgbe_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 		else
 			ri->iri_rsstype = M_HASHTYPE_OPAQUE_HASH;
 	}
-	ri->iri_vtag = vtag;
-	ri->iri_nfrags = i;
-	if (vtag)
+	if ((rxr->vtag_strip) && (staterr & IXGBE_RXD_STAT_VP)) {
+		ri->iri_vtag = le16toh(rxd->wb.upper.vlan);
 		ri->iri_flags |= M_VLANTAG;
+	}
+
+	ri->iri_nfrags = i;
 	return (0);
 } /* ixgbe_isc_rxd_pkt_get */
 
diff --git a/sys/dev/ixl/ixl_txrx.c b/sys/dev/ixl/ixl_txrx.c
index 58ae751e5e10..20050e73c09b 100644
--- a/sys/dev/ixl/ixl_txrx.c
+++ b/sys/dev/ixl/ixl_txrx.c
@@ -663,7 +663,7 @@ ixl_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 	struct rx_ring		*rxr = &que->rxr;
 	union i40e_rx_desc	*cur;
 	u32		status, error;
-	u16		plen, vtag;
+	u16		plen;
 	u64		qword;
 	u8		ptype;
 	bool		eop;
@@ -694,10 +694,6 @@ ixl_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 
 		cur->wb.qword1.status_error_len = 0;
 		eop = (status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT));
-		if (status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT))
-			vtag = le16toh(cur->wb.qword0.lo_dword.l2tag1);
-		else
-			vtag = 0;
 
 		/*
 		** Make sure bad packets are discarded,
@@ -724,10 +720,11 @@ ixl_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
 		rxr->csum_errs += ixl_rx_checksum(ri, status, error, ptype);
 	ri->iri_flowid = le32toh(cur->wb.qword0.hi_dword.rss);
 	ri->iri_rsstype = ixl_ptype_to_hash(ptype);
-	ri->iri_vtag = vtag;
-	ri->iri_nfrags = i;
-	if (vtag)
+	if (status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)) {
+		ri->iri_vtag = le16toh(cur->wb.qword0.lo_dword.l2tag1);
 		ri->iri_flags |= M_VLANTAG;
+	}
+	ri->iri_nfrags = i;
 	return (0);
 }