From: Julian Wiedmann <jwi@linux.ibm.com>
Subject: s390/qeth: recognize non-IP multicast on L3 transmit
Patch-mainline: v4.16-rc1
Git-commit: a65d14104349db217edfcd535521f2d61859cc1f
References: FATE#326350, LTC#169511, bsc#1113509

Summary:     qeth: performance improvements
Description: This adds recent functional and performance improvements for the
             qeth network driver.
             Primarily this brings Scatter-Gather support for HiperSockets,
             reduced CPU consumption in the L3 IPv4 transmit path for OSA,
             improved Promiscuous Mode performance due to IFF_UNICAST_FLT,
             support for Scatter-Gather on z/VM virtual NICs, and
             support for delayed GRO flushing.

             For sanity & stability reasons, this effectively constitutes a
             backport of the qeth device driver from 4.19 mainline.
             

Upstream-Description:

             s390/qeth: recognize non-IP multicast on L3 transmit

             When
             1. an skb has no neighbour, and
             2. skb->protocol is not IP[V6],

             we select the skb's cast type based on its destination MAC address.

             The multicast check is currently restricted to Multicast IP-mapped MACs.
             Extend it to also cover non-IP Multicast MACs.

             Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
             Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/s390/net/qeth_core.h    |    3 ---
 drivers/s390/net/qeth_l3_main.c |    3 +--
 2 files changed, 1 insertion(+), 5 deletions(-)

--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -503,9 +503,6 @@ struct qeth_qdio_info {
 	int default_out_queue;
 };
 
-#define QETH_ETH_MAC_V4      0x0100 /* like v4 */
-#define QETH_ETH_MAC_V6      0x3333 /* like v6 */
-
 /**
  * buffer stuff for read channel
  */
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2344,7 +2344,6 @@ static int qeth_l3_do_ioctl(struct net_d
 
 static int qeth_l3_get_cast_type(struct sk_buff *skb)
 {
-	u16 hdr_mac = *((u16 *)skb->data);
 	struct neighbour *n = NULL;
 	struct dst_entry *dst;
 
@@ -2376,7 +2375,7 @@ static int qeth_l3_get_cast_type(struct
 	/* ... and MAC address */
 	if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, skb->dev->broadcast))
 		return RTN_BROADCAST;
-	if (hdr_mac == QETH_ETH_MAC_V4 || hdr_mac == QETH_ETH_MAC_V6)
+	if (is_multicast_ether_addr(eth_hdr(skb)->h_dest))
 		return RTN_MULTICAST;
 
 	/* default to unicast */