myri10ge: add IPv6 TSO support

Add support for IPv6 TSO to the myri10ge driver.

Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/net/myri10ge/myri10ge.c b/drivers/net/myri10ge/myri10ge.c
index 5c103128e2484d939628a641205b367e92efeae6..6d5af080d7d5e0d0c47c361d58a26447cf32cc1f 100644 (file)
--- a/drivers/net/myri10ge/myri10ge.c
+++ b/drivers/net/myri10ge/myri10ge.c
@@ -214,6 +214,8 @@ struct myri10ge_priv {
        unsigned long serial_number;
        int vendor_specific_offset;
        int fw_multicast_support;
+       unsigned long features;
+       u32 max_tso6;
        u32 read_dma;
        u32 write_dma;
        u32 read_write_dma;
@@ -311,6 +313,7 @@ MODULE_PARM_DESC(myri10ge_wcfifo, "Enable WC Fifo when WC is enabled\n");
 #define myri10ge_pio_copy(to,from,size) __iowrite64_copy(to,from,size/8)
 
 static void myri10ge_set_multicast_list(struct net_device *dev);
+static int myri10ge_sw_tso(struct sk_buff *skb, struct net_device *dev);
 
 static inline void put_be32(__be32 val, __be32 __iomem * p)
 {
@@ -612,6 +615,7 @@ static int myri10ge_load_firmware(struct myri10ge_priv *mgp)
        __be32 buf[16];
        u32 dma_low, dma_high, size;
        int status, i;
+       struct myri10ge_cmd cmd;
 
        size = 0;
        status = myri10ge_load_hotplug_firmware(mgp, &size);
@@ -688,6 +692,14 @@ static int myri10ge_load_firmware(struct myri10ge_priv *mgp)
        dev_info(&mgp->pdev->dev, "handoff confirmed\n");
        myri10ge_dummy_rdma(mgp, 1);
 
+       /* probe for IPv6 TSO support */
+       mgp->features = NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_TSO;
+       status = myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_MAX_TSO6_HDR_SIZE,
+                                  &cmd, 0);
+       if (status == 0) {
+               mgp->max_tso6 = cmd.data0;
+               mgp->features |= NETIF_F_TSO6;
+       }
        return 0;
 }
 
@@ -1384,6 +1396,18 @@ static int myri10ge_set_rx_csum(struct net_device *netdev, u32 csum_enabled)
        return 0;
 }
 
+static int myri10ge_set_tso(struct net_device *netdev, u32 tso_enabled)
+{
+       struct myri10ge_priv *mgp = netdev_priv(netdev);
+       unsigned long flags = mgp->features & (NETIF_F_TSO6 | NETIF_F_TSO);
+
+       if (tso_enabled)
+               netdev->features |= flags;
+       else
+               netdev->features &= ~flags;
+       return 0;
+}
+
 static const char myri10ge_gstrings_stats[][ETH_GSTRING_LEN] = {
        "rx_packets", "tx_packets", "rx_bytes", "tx_bytes", "rx_errors",
        "tx_errors", "rx_dropped", "tx_dropped", "multicast", "collisions",
@@ -1508,7 +1532,7 @@ static const struct ethtool_ops myri10ge_ethtool_ops = {
        .set_rx_csum = myri10ge_set_rx_csum,
        .set_tx_csum = ethtool_op_set_tx_hw_csum,
        .set_sg = ethtool_op_set_sg,
-       .set_tso = ethtool_op_set_tso,
+       .set_tso = myri10ge_set_tso,
        .get_link = ethtool_op_get_link,
        .get_strings = myri10ge_get_strings,
        .get_sset_count = myri10ge_get_sset_count,
@@ -2166,7 +2190,8 @@ again:
                pseudo_hdr_offset = cksum_offset + skb->csum_offset;
                /* If the headers are excessively large, then we must
                 * fall back to a software checksum */
-               if (unlikely(cksum_offset > 255 || pseudo_hdr_offset > 127)) {
+               if (unlikely(!mss && (cksum_offset > 255 ||
+                                     pseudo_hdr_offset > 127))) {
                        if (skb_checksum_help(skb))
                                goto drop;
                        cksum_offset = 0;
@@ -2186,9 +2211,18 @@ again:
                /* negative cum_len signifies to the
                 * send loop that we are still in the
                 * header portion of the TSO packet.
-                * TSO header must be at most 134 bytes long */
+                * TSO header can be at most 1KB long */
                cum_len = -(skb_transport_offset(skb) + tcp_hdrlen(skb));
 
+               /* for IPv6 TSO, the checksum offset stores the
+                * TCP header length, to save the firmware from
+                * the need to parse the headers */
+               if (skb_is_gso_v6(skb)) {
+                       cksum_offset = tcp_hdrlen(skb);
+                       /* Can only handle headers <= max_tso6 long */
+                       if (unlikely(-cum_len > mgp->max_tso6))
+                               return myri10ge_sw_tso(skb, dev);
+               }
                /* for TSO, pseudo_hdr_offset holds mss.
                 * The firmware figures out where to put
                 * the checksum by parsing the header. */
@@ -2303,10 +2337,12 @@ again:
                        req++;
                        count++;
                        rdma_count++;
-                       if (unlikely(cksum_offset > seglen))
-                               cksum_offset -= seglen;
-                       else
-                               cksum_offset = 0;
+                       if (cksum_offset != 0 && !(mss && skb_is_gso_v6(skb))) {
+                               if (unlikely(cksum_offset > seglen))
+                                       cksum_offset -= seglen;
+                               else
+                                       cksum_offset = 0;
+                       }
                }
                if (frag_idx == frag_cnt)
                        break;
@@ -2389,6 +2425,41 @@ drop:
 
 }
 
+static int myri10ge_sw_tso(struct sk_buff *skb, struct net_device *dev)
+{
+       struct sk_buff *segs, *curr;
+       struct myri10ge_priv *mgp = dev->priv;
+       int status;
+
+       segs = skb_gso_segment(skb, dev->features & ~NETIF_F_TSO6);
+       if (unlikely(IS_ERR(segs)))
+               goto drop;
+
+       while (segs) {
+               curr = segs;
+               segs = segs->next;
+               curr->next = NULL;
+               status = myri10ge_xmit(curr, dev);
+               if (status != 0) {
+                       dev_kfree_skb_any(curr);
+                       if (segs != NULL) {
+                               curr = segs;
+                               segs = segs->next;
+                               curr->next = NULL;
+                               dev_kfree_skb_any(segs);
+                       }
+                       goto drop;
+               }
+       }
+       dev_kfree_skb_any(skb);
+       return 0;
+
+drop:
+       dev_kfree_skb_any(skb);
+       mgp->stats.tx_dropped += 1;
+       return 0;
+}
+
 static struct net_device_stats *myri10ge_get_stats(struct net_device *dev)
 {
        struct myri10ge_priv *mgp = netdev_priv(dev);
@@ -3076,7 +3147,7 @@ static int myri10ge_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
        netdev->change_mtu = myri10ge_change_mtu;
        netdev->set_multicast_list = myri10ge_set_multicast_list;
        netdev->set_mac_address = myri10ge_set_mac_address;
-       netdev->features = NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_TSO;
+       netdev->features = mgp->features;
        if (dac_enabled)
                netdev->features |= NETIF_F_HIGHDMA;