qeth: rework TSO functions
The maximum TSO size OSA can handle is 15 * PAGE_SIZE. This
patch reduces gso_max_size to this value and adds some sanity
checks and statistics to the TSO implementation.
Since only layer 3 is able to do TSO move all TSO related functions
to the qeth_l3 module.
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 03f67bb..2048b43 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -41,6 +41,32 @@
static int __qeth_l3_set_online(struct ccwgroup_device *, int);
static int __qeth_l3_set_offline(struct ccwgroup_device *, int);
+int qeth_l3_set_large_send(struct qeth_card *card,
+ enum qeth_large_send_types type)
+{
+ int rc = 0;
+
+ card->options.large_send = type;
+ if (card->dev == NULL)
+ return 0;
+
+ if (card->options.large_send == QETH_LARGE_SEND_TSO) {
+ if (qeth_is_supported(card, IPA_OUTBOUND_TSO)) {
+ card->dev->features |= NETIF_F_TSO | NETIF_F_SG |
+ NETIF_F_HW_CSUM;
+ } else {
+ card->dev->features &= ~(NETIF_F_TSO | NETIF_F_SG |
+ NETIF_F_HW_CSUM);
+ card->options.large_send = QETH_LARGE_SEND_NO;
+ rc = -EOPNOTSUPP;
+ }
+ } else {
+ card->dev->features &= ~(NETIF_F_TSO | NETIF_F_SG |
+ NETIF_F_HW_CSUM);
+ card->options.large_send = QETH_LARGE_SEND_NO;
+ }
+ return rc;
+}
static int qeth_l3_isxdigit(char *buf)
{
@@ -2686,6 +2712,24 @@
*(__sum16 *)(skb->data + offset) = csum_fold(csum);
}
+static inline int qeth_l3_tso_elements(struct sk_buff *skb)
+{
+ unsigned long tcpd = (unsigned long)tcp_hdr(skb) +
+ tcp_hdr(skb)->doff * 4;
+ int tcpd_len = skb->len - (tcpd - (unsigned long)skb->data);
+ int elements = PFN_UP(tcpd + tcpd_len) - PFN_DOWN(tcpd);
+ elements += skb_shinfo(skb)->nr_frags;
+ return elements;
+}
+
+static inline int qeth_l3_tso_check(struct sk_buff *skb)
+{
+ int len = ((unsigned long)tcp_hdr(skb) + tcp_hdr(skb)->doff * 4) -
+ (unsigned long)skb->data;
+ return (((unsigned long)skb->data & PAGE_MASK) !=
+ (((unsigned long)skb->data + len) & PAGE_MASK));
+}
+
static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
int rc;
@@ -2779,16 +2823,21 @@
/* fix hardware limitation: as long as we do not have sbal
* chaining we can not send long frag lists
*/
- if ((large_send == QETH_LARGE_SEND_TSO) &&
- ((skb_shinfo(new_skb)->nr_frags + 2) > 16)) {
- if (skb_linearize(new_skb))
- goto tx_drop;
+ if (large_send == QETH_LARGE_SEND_TSO) {
+ if (qeth_l3_tso_elements(new_skb) + 1 > 16) {
+ if (skb_linearize(new_skb))
+ goto tx_drop;
+ if (card->options.performance_stats)
+ card->perf_stats.tx_lin++;
+ }
}
if ((large_send == QETH_LARGE_SEND_TSO) &&
(cast_type == RTN_UNSPEC)) {
hdr = (struct qeth_hdr *)skb_push(new_skb,
sizeof(struct qeth_hdr_tso));
+ if (qeth_l3_tso_check(new_skb))
+ QETH_DBF_MESSAGE(2, "tso skb misaligned\n");
memset(hdr, 0, sizeof(struct qeth_hdr_tso));
qeth_l3_fill_header(card, hdr, new_skb, ipv, cast_type);
qeth_tso_fill_header(card, hdr, new_skb);
@@ -2931,20 +2980,15 @@
static int qeth_l3_ethtool_set_tso(struct net_device *dev, u32 data)
{
struct qeth_card *card = dev->ml_priv;
+ int rc = 0;
if (data) {
- if (card->options.large_send == QETH_LARGE_SEND_NO) {
- if (card->info.type == QETH_CARD_TYPE_IQD)
- return -EPERM;
- else
- card->options.large_send = QETH_LARGE_SEND_TSO;
- dev->features |= NETIF_F_TSO;
- }
+ rc = qeth_l3_set_large_send(card, QETH_LARGE_SEND_TSO);
} else {
dev->features &= ~NETIF_F_TSO;
card->options.large_send = QETH_LARGE_SEND_NO;
}
- return 0;
+ return rc;
}
static const struct ethtool_ops qeth_l3_ethtool_ops = {
@@ -3060,6 +3104,7 @@
NETIF_F_HW_VLAN_RX |
NETIF_F_HW_VLAN_FILTER;
card->dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
+ card->dev->gso_max_size = 15 * PAGE_SIZE;
SET_NETDEV_DEV(card->dev, &card->gdev->dev);
return register_netdev(card->dev);
@@ -3189,7 +3234,7 @@
goto out_remove;
} else
card->lan_online = 1;
- qeth_set_large_send(card, card->options.large_send);
+ qeth_l3_set_large_send(card, card->options.large_send);
rc = qeth_l3_setadapter_parms(card);
if (rc)