GRETH: avoid overwrite IP-stack's IP-frags checksum

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>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/net/greth.c b/drivers/net/greth.c
index 58ec74a73150..52a39000c42c 100644
--- a/drivers/net/greth.c
+++ b/drivers/net/greth.c
@@ -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 */