net/iavf: fix jumbo frame flag condition

[ upstream commit 7abd466 ]

The jumbo frame uses the 'RTE_ETHER_MAX_LEN' as boundary condition,
but the Ether overhead is larger than 18 when it supports dual VLAN tags.
That will cause the jumbo flag rx offload is wrong when MTU size is
'RTE_ETHER_MTU'.

This fix will change the boundary condition with 'RTE_ETHER_MTU' and
overhead, that perhaps impacts the cases of the jumbo frame related.

Fixes: 3fd7a37 ("net/avf: enable ops for MTU setting")
Fixes: 69dd4c3 ("net/avf: enable queue and device")

Signed-off-by: Steve Yang <stevex.yang@intel.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

drivers/net/iavf/iavf.h

@@ -58,6 +58,7 @@
 #define IAVF_VLAN_TAG_SIZE               4
 #define IAVF_ETH_OVERHEAD \
 	(RTE_ETHER_HDR_LEN + RTE_ETHER_CRC_LEN + IAVF_VLAN_TAG_SIZE * 2)
+#define IAVF_ETH_MAX_LEN (RTE_ETHER_MTU + IAVF_ETH_OVERHEAD)
 
 #define IAVF_32_BIT_WIDTH (CHAR_BIT * 4)
 #define IAVF_48_BIT_WIDTH (CHAR_BIT * 6)

drivers/net/iavf/iavf_ethdev.c

@@ -275,23 +275,23 @@ iavf_init_rxq(struct rte_eth_dev *dev, struct iavf_rx_queue *rxq)
 	 * correctly.
 	 */
 	if (dev->data->dev_conf.rxmode.offloads & DEV_RX_OFFLOAD_JUMBO_FRAME) {
-		if (max_pkt_len <= RTE_ETHER_MAX_LEN ||
+		if (max_pkt_len <= IAVF_ETH_MAX_LEN ||
 		    max_pkt_len > IAVF_FRAME_SIZE_MAX) {
 			PMD_DRV_LOG(ERR, "maximum packet length must be "
 				    "larger than %u and smaller than %u, "
 				    "as jumbo frame is enabled",
-				    (uint32_t)RTE_ETHER_MAX_LEN,
+				    (uint32_t)IAVF_ETH_MAX_LEN,
 				    (uint32_t)IAVF_FRAME_SIZE_MAX);
 			return -EINVAL;
 		}
 	} else {
 		if (max_pkt_len < RTE_ETHER_MIN_LEN ||
-		    max_pkt_len > RTE_ETHER_MAX_LEN) {
+		    max_pkt_len > IAVF_ETH_MAX_LEN) {
 			PMD_DRV_LOG(ERR, "maximum packet length must be "
 				    "larger than %u and smaller than %u, "
 				    "as jumbo frame is disabled",
 				    (uint32_t)RTE_ETHER_MIN_LEN,
-				    (uint32_t)RTE_ETHER_MAX_LEN);
+				    (uint32_t)IAVF_ETH_MAX_LEN);
 			return -EINVAL;
 		}
 	}
@@ -1007,7 +1007,7 @@ iavf_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 		return -EBUSY;
 	}
 
-	if (frame_size > RTE_ETHER_MAX_LEN)
+	if (frame_size > IAVF_ETH_MAX_LEN)
 		dev->data->dev_conf.rxmode.offloads |=
 				DEV_RX_OFFLOAD_JUMBO_FRAME;
 	else