[PATCH v3] net/netvsc: fix parsing of VLAN metadata

[Alan Elder <alan.elder@microsoft.com>]

The previous code incorrectly parsed the VLAN ID and priority.
If the 16-bits of VLAN ID and priority/CFI on the wire was
0123456789ABCDEF the code parsed it as 456789ABCDEF3012.  There
were macros defined to handle this conversion but they were not
used.

This fix takes an approach similar to the Linux netvsc driver and
defines an explicit structure to use for parsing.

Fixes: 4e9c73e96e83 ("net/netvsc: add Hyper-V network device")
Cc: sthemmin@microsoft.com
Cc: stable@dpdk.org

Signed-off-by: Alan Elder <alan.elder@microsoft.com>
---
 .mailmap                     |  1 +
 drivers/net/netvsc/hn_rxtx.c | 23 +++++++++++++++++------
 drivers/net/netvsc/ndis.h    | 23 +++++++++++++----------
 3 files changed, 31 insertions(+), 16 deletions(-)

diff --git a/.mailmap b/.mailmap
index a0756974e2..eca02318d6 100644
--- a/.mailmap
+++ b/.mailmap
@@ -33,6 +33,7 @@ Alain Leon <xerebz@gmail.com>
 Alan Brady <alan.brady@intel.com>
 Alan Carew <alan.carew@intel.com>
 Alan Dewar <alan.dewar@att.com> <adewar@brocade.com>
+Alan Elder <alan.elder@microsoft.com>
 Alan Liu <zaoxingliu@gmail.com>
 Alan Winkowski <walan@marvell.com>
 Alejandro Lucero <alejandro.lucero@netronome.com>
diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
index e4f5015aa3..e3b9899f1e 100644
--- a/drivers/net/netvsc/hn_rxtx.c
+++ b/drivers/net/netvsc/hn_rxtx.c
@@ -42,8 +42,13 @@
 #define HN_TXD_CACHE_SIZE	32 /* per cpu tx_descriptor pool cache */
 #define HN_RXQ_EVENT_DEFAULT	2048
 
+#define HN_VLAN_PRIO_MASK	0xe000 /* Priority Code Point */
+#define HN_VLAN_PRIO_SHIFT	13
+#define HN_VLAN_CFI_MASK	0x1000 /* Canonical Format Indicator / Drop Eligible Indicator */
+#define HN_VLAN_VID_MASK	0x0fff /* VLAN Identifier */
+
 struct hn_rxinfo {
-	uint32_t	vlan_info;
+	struct ndis_pkt_vlan_info vlan_info;
 	uint32_t	csum_info;
 	uint32_t	hash_info;
 	uint32_t	hash_value;
@@ -477,7 +482,7 @@ hn_rndis_rxinfo(const void *info_data, unsigned int info_dlen,
 		case NDIS_PKTINFO_TYPE_VLAN:
 			if (unlikely(dlen < NDIS_VLAN_INFO_SIZE))
 				return -EINVAL;
-			info->vlan_info = *((const uint32_t *)data);
+			info->vlan_info = *((const struct ndis_pkt_vlan_info *)data);
 			mask |= HN_RXINFO_VLAN;
 			break;
 
@@ -611,8 +616,10 @@ static void hn_rxpkt(struct hn_rx_queue *rxq, struct hn_rx_bufinfo *rxb,
 					   RTE_PTYPE_L3_MASK |
 					   RTE_PTYPE_L4_MASK);
 
-	if (info->vlan_info != HN_NDIS_VLAN_INFO_INVALID) {
-		m->vlan_tci = info->vlan_info;
+	if (info->vlan_info.value != HN_NDIS_VLAN_INFO_INVALID) {
+		m->vlan_tci = info->vlan_info.vlanid |
+				(info->vlan_info.pri << HN_VLAN_PRIO_SHIFT) |
+				(info->vlan_info.cfi ? HN_VLAN_CFI_MASK : 0);
 		m->ol_flags |= RTE_MBUF_F_RX_VLAN_STRIPPED | RTE_MBUF_F_RX_VLAN;
 
 		/* NDIS always strips tag, put it back if necessary */
@@ -669,7 +676,7 @@ static void hn_rndis_rx_data(struct hn_rx_queue *rxq,
 	unsigned int pktinfo_off, pktinfo_len;
 	const struct rndis_packet_msg *pkt = data;
 	struct hn_rxinfo info = {
-		.vlan_info = HN_NDIS_VLAN_INFO_INVALID,
+		.vlan_info.value = HN_NDIS_VLAN_INFO_INVALID,
 		.csum_info = HN_NDIS_RXCSUM_INFO_INVALID,
 		.hash_info = HN_NDIS_HASH_INFO_INVALID,
 	};
@@ -1332,7 +1339,11 @@ static void hn_encap(struct rndis_packet_msg *pkt,
 	if (m->ol_flags & RTE_MBUF_F_TX_VLAN) {
 		pi_data = hn_rndis_pktinfo_append(pkt, NDIS_VLAN_INFO_SIZE,
 						  NDIS_PKTINFO_TYPE_VLAN);
-		*pi_data = m->vlan_tci;
+		struct ndis_pkt_vlan_info *vlan = (struct ndis_pkt_vlan_info *)pi_data;
+		vlan->value = 0;
+		vlan->vlanid = (m->vlan_tci & HN_VLAN_VID_MASK);
+		vlan->cfi = (!!(m->vlan_tci & HN_VLAN_CFI_MASK));
+		vlan->pri = ((m->vlan_tci & HN_VLAN_PRIO_MASK) >> HN_VLAN_PRIO_SHIFT);
 	}
 
 	if (m->ol_flags & RTE_MBUF_F_TX_TCP_SEG) {
diff --git a/drivers/net/netvsc/ndis.h b/drivers/net/netvsc/ndis.h
index d97a397a86..a1e587c738 100644
--- a/drivers/net/netvsc/ndis.h
+++ b/drivers/net/netvsc/ndis.h
@@ -316,16 +316,19 @@ struct ndis_offload {
  */
 
 /* VLAN */
-#define	NDIS_VLAN_INFO_SIZE		sizeof(uint32_t)
-#define	NDIS_VLAN_INFO_PRI_MASK		0x0007
-#define	NDIS_VLAN_INFO_CFI_MASK		0x0008
-#define	NDIS_VLAN_INFO_ID_MASK		0xfff0
-#define	NDIS_VLAN_INFO_MAKE(id, pri, cfi)	\
-	(((pri) & NDIS_VLAN_INFO_PRI_MASK) |	\
-	 (((cfi) & 0x1) << 3) | (((id) & 0xfff) << 4))
-#define	NDIS_VLAN_INFO_ID(inf)		(((inf) & NDIS_VLAN_INFO_ID_MASK) >> 4)
-#define	NDIS_VLAN_INFO_CFI(inf)		(((inf) & NDIS_VLAN_INFO_CFI_MASK) >> 3)
-#define	NDIS_VLAN_INFO_PRI(inf)		((inf) & NDIS_VLAN_INFO_PRI_MASK)
+struct ndis_pkt_vlan_info {
+	union {
+		struct {
+			uint32_t pri:3; /* User Priority */
+			uint32_t cfi:1; /* Canonical Format ID / DEI */
+			uint32_t vlanid:12; /* VLAN ID */
+			uint32_t reserved:16;
+		};
+		uint32_t value;
+	};
+};
+
+#define	NDIS_VLAN_INFO_SIZE		sizeof(struct ndis_pkt_vlan_info)
 
 /* Reception checksum */
 #define	NDIS_RXCSUM_INFO_SIZE		sizeof(uint32_t)
-- 
2.25.1