commit 55508d601dab7df5cbcc7a63f4be8620eface204
author Michał Mirosław <mirq-linux@rere.qmqm.pl> Tue Dec 14 15:24:08 2010 +0000
committer David S. Miller <davem@davemloft.net> Thu Dec 16 14:43:14 2010 -0800
tree 346f30fae9c726d2e73aba2e37ce1e4a31dcea8c
parent 04fb451eff978ca059399eab83d5594b073caf6f

net: Use skb_checksum_start_offset()

Replace skb->csum_start - skb_headroom(skb) with skb_checksum_start_offset().

Note for usb/smsc95xx: skb->data - skb->head == skb_headroom(skb).

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/tun.c

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 55f3a3e..7599c45 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -757,7 +757,7 @@
 
 		if (skb->ip_summed == CHECKSUM_PARTIAL) {
 			gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
-			gso.csum_start = skb->csum_start - skb_headroom(skb);
+			gso.csum_start = skb_checksum_start_offset(skb);
 			gso.csum_offset = skb->csum_offset;
 		} /* else everything is zero */