[PATCH net-next 8/8] s390/qeth: trust non-IP cast type in qeth_l3_fill_header()

Julian Wiedmann
2019-04-25T16:26:01Z

When building the L3 HW header for non-IP packets, trust the cast type
that was passed as parameter. qeth_l3_get_cast_type() has most likely
also used h_dest to determine the cast type, so we get the same
result, and can remove that duplicated code.
In the unlikely case that we would get a _different_ cast type, then
that's based off a route lookup and should be considered authoritative.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
---
drivers/s390/net/qeth_l3_main.c | 11 +++--------
1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index b5d76ebb488a..0271833da6a2 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -1976,19 +1976,14 @@ static void qeth_l3_fill_header(struct qeth_qdio_out_q *queue,
hdr->hdr.l3.vlan_id = ntohs(veth->h_vlan_TCI);
}

+ l3_hdr->flags = qeth_l3_cast_type_to_flag(cast_type);
+
/* OSA only: */
if (!ipv) {
- hdr->hdr.l3.flags = QETH_HDR_PASSTHRU;
- if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest,
- skb->dev->broadcast))
- hdr->hdr.l3.flags |= QETH_CAST_BROADCAST;
- else
- hdr->hdr.l3.flags |= (cast_type == RTN_MULTICAST) ?
- QETH_CAST_MULTICAST : QETH_CAST_UNICAST;
+ l3_hdr->flags |= QETH_HDR_PASSTHRU;
return;
}

- hdr->hdr.l3.flags = qeth_l3_cast_type_to_flag(cast_type);
rcu_read_lock();
if (ipv == 4) {
struct rtable *rt = skb_rtable(skb);
--
2.16.4