[PATCH 2.6.9-rc1-mm4 3/4] r8169: TSO support.

[Francois Romieu <romieu@xxxxxxxxxxxxx>]

TSO support. Suggestion of Jeff Garzik.

Signed-off-by: Francois Romieu <romieu@xxxxxxxxxxxxx>

diff -puN drivers/net/r8169.c~r8169-160 drivers/net/r8169.c
--- linux-2.6.9-rc1/drivers/net/r8169.c~r8169-160       2004-09-08 
22:53:47.000000000 +0200
+++ linux-2.6.9-rc1-fr/drivers/net/r8169.c      2004-09-08 22:53:47.000000000 
+0200
@@ -323,6 +323,9 @@ enum _DescStatusBit {
        LastFrag        = (1 << 28), /* Final segment of a packet */
 
        /* Tx private */
+       LargeSend       = (1 << 27), /* TCP Large Send Offload (TSO) */
+       MSSShift        = 16,        /* MSS value position */
+       MSSMask         = 0xfff,     /* MSS value + LargeSend bit: 12 bits */
        IPCS            = (1 << 18), /* Calculate IP checksum */
        UDPCS           = (1 << 17), /* Calculate UDP/IP checksum */
        TCPCS           = (1 << 16), /* Calculate TCP/IP checksum */
@@ -844,6 +847,8 @@ static struct ethtool_ops rtl8169_ethtoo
        .set_tx_csum            = ethtool_op_set_tx_csum,
        .get_sg                 = ethtool_op_get_sg,
        .set_sg                 = ethtool_op_set_sg,
+       .get_tso                = ethtool_op_get_tso,
+       .set_tso                = ethtool_op_set_tso,
        .get_regs               = rtl8169_get_regs,
 };
 
@@ -1745,8 +1750,14 @@ static int rtl8169_xmit_frags(struct rtl
        return cur_frag;
 }
 
-static inline u32 rtl8169_tx_csum(struct sk_buff *skb)
+static inline u32 rtl8169_tso_csum(struct sk_buff *skb, struct net_device *dev)
 {
+       if (dev->features & NETIF_F_TSO) {
+               u32 mss = skb_shinfo(skb)->tso_size;
+
+               if (mss)
+                       return LargeSend | ((mss & MSSMask) << MSSShift);
+       }
        if (skb->ip_summed == CHECKSUM_HW) {
                const struct iphdr *ip = skb->nh.iph;
 
@@ -1754,7 +1765,7 @@ static inline u32 rtl8169_tx_csum(struct
                        return IPCS | TCPCS;
                else if (ip->protocol == IPPROTO_UDP)
                        return IPCS | UDPCS;
-               BUG();
+               WARN_ON(1);     /* we need a WARN() */
        }
        return 0;
 }
@@ -1779,7 +1790,7 @@ static int rtl8169_start_xmit(struct sk_
        if (unlikely(le32_to_cpu(txd->opts1) & DescOwn))
                goto err_stop;
 
-       opts1 = DescOwn | rtl8169_tx_csum(skb);
+       opts1 = DescOwn | rtl8169_tso_csum(skb, dev);
 
        frags = rtl8169_xmit_frags(tp, skb, opts1);
        if (frags) {

_