[PATCH net-next 2/8] s390/qeth: handle af_iucv skbs in qeth_l3_fill_header()

Julian Wiedmann
2018-11-08T14:06:16Z

Filling the HW header from one single function will make it easier to
rip out all the duplicated transmit code in qeth_l3_xmit(). On top, this
saves one conditional branch in the TSO path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
---
drivers/s390/net/qeth_core.h | 2 +-
drivers/s390/net/qeth_l3_main.c | 45 +++++++++++++++--------------------------
2 files changed, 17 insertions(+), 30 deletions(-)

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 99af1a0a3314..d50d91219cf3 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -314,7 +314,7 @@ struct qeth_hdr_layer3 {
__u16 frame_offset;
union {
/* TX: */
- u8 ipv6_addr[16];
+ struct in6_addr ipv6_addr;
struct ipv4 {
u8 res[12];
u32 addr;
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index f08b745c2007..004085344e85 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -1929,22 +1929,6 @@ static int qeth_l3_get_cast_type(struct sk_buff *skb)
}
}

-static void qeth_l3_fill_af_iucv_hdr(struct qeth_hdr *hdr, struct sk_buff *skb,
- unsigned int data_len)
-{
- char daddr[16];
-
- hdr->hdr.l3.id = QETH_HEADER_TYPE_LAYER3;
- hdr->hdr.l3.length = data_len;
- hdr->hdr.l3.flags = QETH_HDR_IPV6 | QETH_CAST_UNICAST;
-
- memset(daddr, 0, sizeof(daddr));
- daddr[0] = 0xfe;
- daddr[1] = 0x80;
- memcpy(&daddr[8], iucv_trans_hdr(skb)->destUserID, 8);
- memcpy(hdr->hdr.l3.next_hop.ipv6_addr, daddr, 16);
-}
-
static u8 qeth_l3_cast_type_to_flag(int cast_type)
{
if (cast_type == RTN_MULTICAST)
@@ -1960,6 +1944,7 @@ static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
struct sk_buff *skb, int ipv, int cast_type,
unsigned int data_len)
{
+ struct qeth_hdr_layer3 *l3_hdr = &hdr->hdr.l3;
struct vlan_ethhdr *veth = vlan_eth_hdr(skb);

hdr->hdr.l3.length = data_len;
@@ -1968,6 +1953,15 @@ static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
hdr->hdr.l3.id = QETH_HEADER_TYPE_L3_TSO;
} else {
hdr->hdr.l3.id = QETH_HEADER_TYPE_LAYER3;
+
+ if (skb->protocol == htons(ETH_P_AF_IUCV)) {
+ l3_hdr->flags = QETH_HDR_IPV6 | QETH_CAST_UNICAST;
+ l3_hdr->next_hop.ipv6_addr.s6_addr16[0] = htons(0xfe80);
+ memcpy(&l3_hdr->next_hop.ipv6_addr.s6_addr32[2],
+ iucv_trans_hdr(skb)->destUserID, 8);
+ return;
+ }
+
if (skb->ip_summed == CHECKSUM_PARTIAL) {
qeth_tx_csum(skb, &hdr->hdr.l3.ext_flags, ipv);
/* some HW requires combined L3+L4 csum offload: */
@@ -2012,13 +2006,11 @@ static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
} else {
/* IPv6 */
const struct rt6_info *rt = skb_rt6_info(skb);
- const struct in6_addr *next_hop;

if (rt && !ipv6_addr_any(&rt->rt6i_gateway))
- next_hop = &rt->rt6i_gateway;
+ l3_hdr->next_hop.ipv6_addr = rt->rt6i_gateway;
else
- next_hop = &ipv6_hdr(skb)->daddr;
- memcpy(hdr->hdr.l3.next_hop.ipv6_addr, next_hop, 16);
+ l3_hdr->next_hop.ipv6_addr = ipv6_hdr(skb)->daddr;

hdr->hdr.l3.flags |= QETH_HDR_IPV6;
if (card->info.type != QETH_CARD_TYPE_IQD)
@@ -2082,15 +2074,10 @@ static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
}
memset(hdr, 0, hw_hdr_len);

- if (skb->protocol == htons(ETH_P_AF_IUCV)) {
- qeth_l3_fill_af_iucv_hdr(hdr, skb, frame_len);
- } else {
- qeth_l3_fill_header(card, hdr, skb, ipv, cast_type, frame_len);
- if (is_tso)
- qeth_fill_tso_ext((struct qeth_hdr_tso *) hdr,
- frame_len - proto_len, skb,
- proto_len);
- }
+ qeth_l3_fill_header(card, hdr, skb, ipv, cast_type, frame_len);
+ if (is_tso)
+ qeth_fill_tso_ext((struct qeth_hdr_tso *) hdr,
+ frame_len - proto_len, skb, proto_len);

is_sg = skb_is_nonlinear(skb);
if (IS_IQD(card)) {
--
2.16.4