[PATCH] Ethernet Bridging: Enable Hardware Checksumming

[Jon Mason <jdmason@us.ibm.com>]

Currently, locally generated ethernet traffic does not take advantage of
hardware checksum offload when acting as a child device under a bridge
device.  This is because the upper layers do not see the available
features of the child devices only the features of the bridge device
(which is empty).  

There is an easy solution for this (see patch below), include hardware
checksum and scatter gather as features of the bridge device.  In the 
case that the physical ethernet device does not support scatter 
gather or hardware checksum, dev_queue_xmit() will check the
dev->features and do the necessary linearization and calculate the
checksum.

Signed-off-by: Jon Mason <jdmason@us.ibm.com>

--- net/bridge/br_device.c.orig	2005-05-13 11:23:02.552751024 -0500
+++ net/bridge/br_device.c	2005-05-13 11:25:39.155943720 -0500
@@ -101,4 +101,5 @@ void br_dev_setup(struct net_device *dev
 	dev->tx_queue_len = 0;
 	dev->set_mac_address = NULL;
 	dev->priv_flags = IFF_EBRIDGE;
+	dev->features = NETIF_F_HW_CSUM | NETIF_F_SG;
 }