[PATCH] Allow TSO to be disabled for forcedeth driver

[Zachary Amsden <zach@vmware.com>]

TSO can cause performance problems in certain environments, and being 
able to turn it on or off is helpful for debugging network issues.  Most 
other network drivers that support TSO allow it to be toggled, so add 
this feature to forcedeth.  Tested by Harald Dunkel, who reported that 
this fixed his network performance issue with VMware.


Implement get / set tso for forcedeth driver.

Signed-off-by: Zachary Amsden <zach@vmware.com>

Index: linux-2.6.17-rc/drivers/net/forcedeth.c
===================================================================
--- linux-2.6.17-rc.orig/drivers/net/forcedeth.c	2006-05-18 13:31:55.000000000 -0700
+++ linux-2.6.17-rc/drivers/net/forcedeth.c	2006-05-31 14:34:53.000000000 -0700
@@ -2615,6 +2615,21 @@ static int nv_nway_reset(struct net_devi
 	return ret;
 }
 
+static int nv_set_tso(struct net_device *dev, u32 value)
+{
+	struct fe_priv *np = netdev_priv(dev);
+	int ret;
+
+	spin_lock_irq(&np->lock);
+	if ((np->driver_data & DEV_HAS_CHECKSUM))
+		ret = ethtool_op_set_tso(dev, value);
+	else
+		ret = value ? -EOPNOTSUPP : 0;
+	spin_unlock_irq(&np->lock);
+
+	return ret;
+}
+
 static struct ethtool_ops ops = {
 	.get_drvinfo = nv_get_drvinfo,
 	.get_link = ethtool_op_get_link,
@@ -2626,6 +2641,8 @@ static struct ethtool_ops ops = {
 	.get_regs = nv_get_regs,
 	.nway_reset = nv_nway_reset,
 	.get_perm_addr = ethtool_op_get_perm_addr,
+	.get_tso = ethtool_op_get_tso,
+	.set_tso = nv_set_tso
 };
 
 static void nv_vlan_rx_register(struct net_device *dev, struct vlan_group *grp)