From d52aec97e5bc40b84fbe348f9d0ab56a6f3face4 Mon Sep 17 00:00:00 2001 From: Eugene Crosser Date: Thu, 16 Jun 2016 16:18:55 +0200 Subject: [PATCH] qeth: enable scatter/gather in layer 2 mode The patch enables NETIF_F_SG flag for OSA in layer 2 mode. It also adds performance accounting for fragmented sends, adds a conditional skb_linearize() attempt if the skb had too many fragments for QDIO SBAL, and fills netdevice->gso_* attributes. Signed-off-by: Eugene Crosser Signed-off-by: Ursula Braun Reviewed-by: Lakhvich Dmitriy Reviewed-by: Thomas Richter Signed-off-by: David S. Miller --- drivers/s390/net/qeth_l2_main.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index faab0b669ca4..ec163e4ededb 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -869,6 +869,7 @@ static int qeth_l2_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) int data_offset = -1; int elements_needed = 0; int hd_len = 0; + int nr_frags; if (card->qdio.do_prio_queueing || (cast_type && card->info.is_multicast_different)) @@ -892,6 +893,17 @@ static int qeth_l2_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) } netif_stop_queue(dev); + /* fix hardware limitation: as long as we do not have sbal + * chaining we can not send long frag lists + */ + if ((card->info.type != QETH_CARD_TYPE_IQD) && + !qeth_get_elements_no(card, new_skb, 0)) { + if (skb_linearize(new_skb)) + goto tx_drop; + if (card->options.performance_stats) + card->perf_stats.tx_lin++; + } + if (card->info.type == QETH_CARD_TYPE_OSN) hdr = (struct qeth_hdr *)skb->data; else { @@ -943,6 +955,14 @@ static int qeth_l2_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) if (!rc) { card->stats.tx_packets++; card->stats.tx_bytes += tx_bytes; + if (card->options.performance_stats) { + nr_frags = skb_shinfo(new_skb)->nr_frags; + if (nr_frags) { + card->perf_stats.sg_skbs_sent++; + /* nr_frags + skb->data */ + card->perf_stats.sg_frags_sent += nr_frags + 1; + } + } if (new_skb != skb) dev_kfree_skb_any(skb); rc = NETDEV_TX_OK; @@ -1118,12 +1138,16 @@ static int qeth_l2_setup_netdev(struct qeth_card *card) &qeth_l2_ethtool_ops : &qeth_l2_osn_ops; card->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER; if (card->info.type == QETH_CARD_TYPE_OSD && !card->info.guestlan) { - card->dev->hw_features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM; + card->dev->hw_features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM | + NETIF_F_SG; /* Turn on RX offloading per default */ card->dev->features |= NETIF_F_RXCSUM; } card->info.broadcast_capable = 1; qeth_l2_request_initial_mac(card); + card->dev->gso_max_size = (QETH_MAX_BUFFER_ELEMENTS(card) - 1) * + PAGE_SIZE; + card->dev->gso_max_segs = (QETH_MAX_BUFFER_ELEMENTS(card) - 1); SET_NETDEV_DEV(card->dev, &card->gdev->dev); netif_napi_add(card->dev, &card->napi, qeth_l2_poll, QETH_NAPI_WEIGHT); netif_carrier_off(card->dev); -- 2.20.1