ice: add support BIG TCP on IPv6

Enable sending BIG TCP packets on IPv6 in the ice driver using generic
ipv6_hopopt_jumbo_remove helper for stripping HBH header.

Tested:
netperf -t TCP_RR -H 2001:db8:0:f101::1  -- -r80000,80000 -O MIN_LATENCY,P90_LATENCY,P99_LATENCY,TRANSACTION_RATE

Tested on two different setups. In both cases, the following settings were
applied after loading the changed driver:

ip link set dev enp175s0f1np1 gso_max_size 130000
ip link set dev enp175s0f1np1 gro_max_size 130000
ip link set dev enp175s0f1np1 mtu 9000

First setup:
Before:
Minimum      90th         99th         Transaction
Latency      Percentile   Percentile   Rate
Microseconds Latency      Latency      Tran/s
             Microseconds Microseconds
134          279          410          3961.584

After:
Minimum      90th         99th         Transaction
Latency      Percentile   Percentile   Rate
Microseconds Latency      Latency      Tran/s
             Microseconds Microseconds
135          178          216          6093.404

The other setup:
Before:
Minimum      90th         99th         Transaction
Latency      Percentile   Percentile   Rate
Microseconds Latency      Latency      Tran/s
             Microseconds Microseconds
218          414          478          2944.765

After:
Minimum      90th         99th         Transaction
Latency      Percentile   Percentile   Rate
Microseconds Latency      Latency      Tran/s
             Microseconds Microseconds
146          238          266          4700.596
Signed-off-by: Pawel Chmielewski <pawel.chmielewski@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/ice/ice.h

@@ -123,6 +123,8 @@
 
 #define ICE_MAX_MTU	(ICE_AQ_SET_MAC_FRAME_SIZE_MAX - ICE_ETH_PKT_HDR_PAD)
 
+#define ICE_MAX_TSO_SIZE 131072
+
 #define ICE_UP_TABLE_TRANSLATE(val, i) \
 		(((val) << ICE_AQ_VSI_UP_TABLE_UP##i##_S) & \
 		  ICE_AQ_VSI_UP_TABLE_UP##i##_M)

drivers/net/ethernet/intel/ice/ice_main.c

@@ -3436,6 +3436,8 @@ static void ice_set_netdev_features(struct net_device *netdev)
 	 * be changed at runtime
 	 */
 	netdev->hw_features |= NETIF_F_RXFCS;
+
+	netif_set_tso_max_size(netdev, ICE_MAX_TSO_SIZE);
 }
 
 /**

drivers/net/ethernet/intel/ice/ice_txrx.c

@@ -2327,6 +2327,9 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring)
 
 	ice_trace(xmit_frame_ring, tx_ring, skb);
 
+	if (unlikely(ipv6_hopopt_jumbo_remove(skb)))
+		goto out_drop;
+
 	count = ice_xmit_desc_count(skb);
 	if (ice_chk_linearize(skb, count)) {
 		if (__skb_linearize(skb))