GRETH: avoid overwrite IP-stack's IP-frags checksum
Daniel Hellstrom [Fri, 9 Sep 2011 05:17:54 +0000 (05:17 +0000)]
The GRETH GBIT core does not do checksum offloading for IP
segmentation. This patch adds a check in the xmit function to
determine if the stack has calculated the checksum for us.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/greth.c

index 58ec74a..52a3900 100644 (file)
@@ -491,7 +491,8 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
        if (nr_frags != 0)
                status = GRETH_TXBD_MORE;
 
-       status |= GRETH_TXBD_CSALL;
+       if (skb->ip_summed == CHECKSUM_PARTIAL)
+               status |= GRETH_TXBD_CSALL;
        status |= skb_headlen(skb) & GRETH_BD_LEN;
        if (greth->tx_next == GRETH_TXBD_NUM_MASK)
                status |= GRETH_BD_WR;
@@ -514,7 +515,9 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
                greth->tx_skbuff[curr_tx] = NULL;
                bdp = greth->tx_bd_base + curr_tx;
 
-               status = GRETH_TXBD_CSALL | GRETH_BD_EN;
+               status = GRETH_BD_EN;
+               if (skb->ip_summed == CHECKSUM_PARTIAL)
+                       status |= GRETH_TXBD_CSALL;
                status |= frag->size & GRETH_BD_LEN;
 
                /* Wrap around descriptor ring */