net/liquidio: fix jumbo frame flag condition for MTU set

[ upstream commit 92c8722 ]

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

This fix will normalize the boundary condition with 'RTE_ETHER_MTU'
and overhead even though current overhead is 18.

Fixes: 9f1c002 ("net/liquidio: add API to set MTU")

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

drivers/net/liquidio/lio_ethdev.c

@@ -484,7 +484,7 @@ lio_dev_mtu_set(struct rte_eth_dev *eth_dev, uint16_t mtu)
 		return -1;
 	}
 
-	if (frame_len > RTE_ETHER_MAX_LEN)
+	if (frame_len > LIO_ETH_MAX_LEN)
 		eth_dev->data->dev_conf.rxmode.offloads |=
 			DEV_RX_OFFLOAD_JUMBO_FRAME;
 	else

drivers/net/liquidio/lio_ethdev.h

@@ -13,6 +13,9 @@
 #define LIO_LSC_TIMEOUT		100000 /* 100000us (100ms) */
 #define LIO_MAX_CMD_TIMEOUT     10000 /* 10000ms (10s) */
 
+/* The max frame size with default MTU */
+#define LIO_ETH_MAX_LEN (RTE_ETHER_MTU + RTE_ETHER_HDR_LEN + RTE_ETHER_CRC_LEN)
+
 #define LIO_DEV(_eth_dev)		((_eth_dev)->data->dev_private)
 
 /* LIO Response condition variable */