Merge branch 's390-qeth-fixes'

Julian Wiedmann says:

====================
s390/qeth: fixes 2017-12-01

please apply the following three fixes for 4.15. These should also go
back to stable.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 9cd569e..15015a2 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -987,6 +987,9 @@
 int qeth_set_features(struct net_device *, netdev_features_t);
 void qeth_recover_features(struct net_device *dev);
 netdev_features_t qeth_fix_features(struct net_device *, netdev_features_t);
+netdev_features_t qeth_features_check(struct sk_buff *skb,
+				      struct net_device *dev,
+				      netdev_features_t features);
 int qeth_vm_request_mac(struct qeth_card *card);
 int qeth_push_hdr(struct sk_buff *skb, struct qeth_hdr **hdr, unsigned int len);
 
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 49b9efe..d9b0e07 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -19,6 +19,11 @@
 #include <linux/mii.h>
 #include <linux/kthread.h>
 #include <linux/slab.h>
+#include <linux/if_vlan.h>
+#include <linux/netdevice.h>
+#include <linux/netdev_features.h>
+#include <linux/skbuff.h>
+
 #include <net/iucv/af_iucv.h>
 #include <net/dsfield.h>
 
@@ -6438,6 +6443,32 @@
 }
 EXPORT_SYMBOL_GPL(qeth_fix_features);
 
+netdev_features_t qeth_features_check(struct sk_buff *skb,
+				      struct net_device *dev,
+				      netdev_features_t features)
+{
+	/* GSO segmentation builds skbs with
+	 *	a (small) linear part for the headers, and
+	 *	page frags for the data.
+	 * Compared to a linear skb, the header-only part consumes an
+	 * additional buffer element. This reduces buffer utilization, and
+	 * hurts throughput. So compress small segments into one element.
+	 */
+	if (netif_needs_gso(skb, features)) {
+		/* match skb_segment(): */
+		unsigned int doffset = skb->data - skb_mac_header(skb);
+		unsigned int hsize = skb_shinfo(skb)->gso_size;
+		unsigned int hroom = skb_headroom(skb);
+
+		/* linearize only if resulting skb allocations are order-0: */
+		if (SKB_DATA_ALIGN(hroom + doffset + hsize) <= SKB_MAX_HEAD(0))
+			features &= ~NETIF_F_SG;
+	}
+
+	return vlan_features_check(skb, features);
+}
+EXPORT_SYMBOL_GPL(qeth_features_check);
+
 static int __init qeth_core_init(void)
 {
 	int rc;
diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index d2537c0..f21c948 100644
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -960,6 +960,7 @@
 	.ndo_stop		= qeth_l2_stop,
 	.ndo_get_stats		= qeth_get_stats,
 	.ndo_start_xmit		= qeth_l2_hard_start_xmit,
+	.ndo_features_check	= qeth_features_check,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_set_rx_mode	= qeth_l2_set_rx_mode,
 	.ndo_do_ioctl		= qeth_do_ioctl,
@@ -1010,6 +1011,7 @@
 	if (card->info.type == QETH_CARD_TYPE_OSD && !card->info.guestlan) {
 		card->dev->hw_features = NETIF_F_SG;
 		card->dev->vlan_features = NETIF_F_SG;
+		card->dev->features |= NETIF_F_SG;
 		/* OSA 3S and earlier has no RX/TX support */
 		if (qeth_is_supported(card, IPA_OUTBOUND_CHECKSUM)) {
 			card->dev->hw_features |= NETIF_F_IP_CSUM;
@@ -1028,8 +1030,6 @@
 
 	card->info.broadcast_capable = 1;
 	qeth_l2_request_initial_mac(card);
-	card->dev->gso_max_size = (QETH_MAX_BUFFER_ELEMENTS(card) - 1) *
-				  PAGE_SIZE;
 	SET_NETDEV_DEV(card->dev, &card->gdev->dev);
 	netif_napi_add(card->dev, &card->napi, qeth_poll, QETH_NAPI_WEIGHT);
 	netif_carrier_off(card->dev);
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index aadd384..2a25f20 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -1376,6 +1376,7 @@
 
 		tmp->u.a4.addr = be32_to_cpu(im4->multiaddr);
 		memcpy(tmp->mac, buf, sizeof(tmp->mac));
+		tmp->is_multicast = 1;
 
 		ipm = qeth_l3_ip_from_hash(card, tmp);
 		if (ipm) {
@@ -2917,6 +2918,7 @@
 	.ndo_stop		= qeth_l3_stop,
 	.ndo_get_stats		= qeth_get_stats,
 	.ndo_start_xmit		= qeth_l3_hard_start_xmit,
+	.ndo_features_check	= qeth_features_check,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_set_rx_mode	= qeth_l3_set_multicast_list,
 	.ndo_do_ioctl		= qeth_do_ioctl,
@@ -2957,6 +2959,7 @@
 				card->dev->vlan_features = NETIF_F_SG |
 					NETIF_F_RXCSUM | NETIF_F_IP_CSUM |
 					NETIF_F_TSO;
+				card->dev->features |= NETIF_F_SG;
 			}
 		}
 	} else if (card->info.type == QETH_CARD_TYPE_IQD) {
@@ -2984,8 +2987,8 @@
 				NETIF_F_HW_VLAN_CTAG_RX |
 				NETIF_F_HW_VLAN_CTAG_FILTER;
 	netif_keep_dst(card->dev);
-	card->dev->gso_max_size = (QETH_MAX_BUFFER_ELEMENTS(card) - 1) *
-				  PAGE_SIZE;
+	netif_set_gso_max_size(card->dev, (QETH_MAX_BUFFER_ELEMENTS(card) - 1) *
+					  PAGE_SIZE);
 
 	SET_NETDEV_DEV(card->dev, &card->gdev->dev);
 	netif_napi_add(card->dev, &card->napi, qeth_poll, QETH_NAPI_WEIGHT);