ethtool: Add NETIF_F_HW_CSUM support

Added support to ethtool for NETIF_F_HW_CSUM.

@@ -256,6 +256,7 @@ struct net_device;
 u32 ethtool_op_get_link(struct net_device *dev);
 u32 ethtool_op_get_tx_csum(struct net_device *dev);
 int ethtool_op_set_tx_csum(struct net_device *dev, u32 data);
+int ethtool_op_set_tx_hw_csum(struct net_device *dev, u32 data);
 u32 ethtool_op_get_sg(struct net_device *dev);
 int ethtool_op_set_sg(struct net_device *dev, u32 data);
 u32 ethtool_op_get_tso(struct net_device *dev);

@@ -29,7 +29,7 @@ u32 ethtool_op_get_link(struct net_devic
 
 u32 ethtool_op_get_tx_csum(struct net_device *dev)
 {
-	return (dev->features & NETIF_F_IP_CSUM) != 0;
+	return (dev->features & (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM)) != 0;
 }
 
 int ethtool_op_set_tx_csum(struct net_device *dev, u32 data)

@@ -42,6 +42,15 @@ int ethtool_op_set_tx_csum(struct net_de
 	return 0;
 }
 
+int ethtool_op_set_tx_hw_csum(struct net_device *dev, u32 data)
+{
+	if (data)
+		dev->features |= NETIF_F_HW_CSUM;
+	else
+		dev->features &= ~NETIF_F_HW_CSUM;
+
+	return 0;
+}
 u32 ethtool_op_get_sg(struct net_device *dev)
 {
 	return (dev->features & NETIF_F_SG) != 0;

@@ -817,3 +826,4 @@ EXPORT_SYMBOL(ethtool_op_get_tx_csum);
 EXPORT_SYMBOL(ethtool_op_set_sg);
 EXPORT_SYMBOL(ethtool_op_set_tso);
 EXPORT_SYMBOL(ethtool_op_set_tx_csum);
+EXPORT_SYMBOL(ethtool_op_set_tx_hw_csum);

From: Jon Mason <[email protected]>
Subject: [PATCH linux-2.6.12-rc4-mm1] ethtool: Add NETIF_F_HW_CSUM support
Date: Mon, 23 May 2005 16:07:57 -0500

You cannot blindly set these flags, you need to provide a method for the driver to override the implementation of this method so it can return and error if it cannot provide support for this feature.

I am only adding a generic function which gives the ability to use NETIF_F_HW_CSUM for ethtool tx offload (instead of only using NETIF_F_IP_CSUM).

If ethtool_set_tx_csum does not point to ethtool_op_set_tx_csum or ethtool_op_set_tx_hw_csum (or a local driver function) then it will return an error. Isn't this sufficient (as it is what currently happening), or am I not sufficently understanding the problem?

Thanks,
Jon

From: Jon Mason <[email protected]>
Date: Mon, 23 May 2005 16:32:55 -0500

Ok, that looks right.

This patch makes perfect sense because it allows for common code to be used by device drivers in their ethtool_ops. So this is the logical way to handle this.

In other words,

drivers/net/sungem.c could do

static struct ethtool_ops gem_ethtool_ops = {

+ .get_tx_csum = ethtool_op_get_tx_csum,
+ .set_tx_csum = ethtool_op_set_tx_hw_csum,
};

From: Stephen Hemminger <[email protected]>
Date: Mon, 23 May 2005 14:53:21 -0700

You're right, of course. I've applied the patch.

Thanks.