[PATCH] mv643xx_eth: Request HW checksum generation only for IPv4

This patch removes the NETIF_F_HW_CSUM flag to be able to use other protocols
than IPv4. Hardware checksums for IPv4 should continue to work because
NETIF_F_IP_CSUM is still set.  The sanity-check has been enhanced to check
the used protocol and to not access skb->iph for non-ipv4-packets.

Signed-off-by: Wolfram Joost <pegasos@frokaschwei.de>
Signed-off-by: Dale Farnsworth <dale@farnsworth.org>

 mv643xx_eth.c |   19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 11 insertions, 8 deletions

diff --git a/drivers/net/mv643xx_eth.c b/drivers/net/mv643xx_eth.c
index f6d4ea175e11..615b3622ea67 100644
--- a/drivers/net/mv643xx_eth.c
+++ b/drivers/net/mv643xx_eth.c
@@ -1148,7 +1148,6 @@ static int mv643xx_eth_start_xmit(struct sk_buff *skb, struct net_device *dev)
                                            5 << ETH_TX_IHL_SHIFT;
                         pkt_info.l4i_chk = 0;
                 } else {
-
                         pkt_info.cmd_sts = ETH_TX_ENABLE_INTERRUPT |
                                            ETH_TX_FIRST_DESC |
                                            ETH_TX_LAST_DESC |
@@ -1156,14 +1155,16 @@ static int mv643xx_eth_start_xmit(struct sk_buff *skb, struct net_device *dev)
                                            ETH_GEN_IP_V_4_CHECKSUM |
                                            skb->nh.iph->ihl << ETH_TX_IHL_SHIFT;
                         /* CPU already calculated pseudo header checksum. */
-                        if (skb->nh.iph->protocol == IPPROTO_UDP) {
+                        if ((skb->protocol == ETH_P_IP) &&
+                            (skb->nh.iph->protocol == IPPROTO_UDP) ) {
                                 pkt_info.cmd_sts |= ETH_UDP_FRAME;
                                 pkt_info.l4i_chk = skb->h.uh->check;
-                        } else if (skb->nh.iph->protocol == IPPROTO_TCP)
+                        } else if ((skb->protocol == ETH_P_IP) &&
+                                   (skb->nh.iph->protocol == IPPROTO_TCP))
                                 pkt_info.l4i_chk = skb->h.th->check;
                         else {
                                 printk(KERN_ERR
-                                        "%s: chksum proto != TCP or UDP\n",
+                                        "%s: chksum proto != IPv4 TCP or UDP\n",
                                         dev->name);
                                 spin_unlock_irqrestore(&mp->lock, flags);
                                 return 1;
@@ -1199,14 +1200,16 @@ static int mv643xx_eth_start_xmit(struct sk_buff *skb, struct net_device *dev)
                                            ETH_GEN_IP_V_4_CHECKSUM |
                                            skb->nh.iph->ihl << ETH_TX_IHL_SHIFT;
                         /* CPU already calculated pseudo header checksum. */
-                        if (skb->nh.iph->protocol == IPPROTO_UDP) {
+                        if ((skb->protocol == ETH_P_IP) &&
+                            (skb->nh.iph->protocol == IPPROTO_UDP)) {
                                 pkt_info.cmd_sts |= ETH_UDP_FRAME;
                                 pkt_info.l4i_chk = skb->h.uh->check;
-                        } else if (skb->nh.iph->protocol == IPPROTO_TCP)
+                        } else if ((skb->protocol == ETH_P_IP) &&
+                                   (skb->nh.iph->protocol == IPPROTO_TCP))
                                 pkt_info.l4i_chk = skb->h.th->check;
                         else {
                                 printk(KERN_ERR
-                                        "%s: chksum proto != TCP or UDP\n",
+                                        "%s: chksum proto != IPv4 TCP or UDP\n",
                                         dev->name);
                                 spin_unlock_irqrestore(&mp->lock, flags);
                                 return 1;
@@ -1421,7 +1424,7 @@ static int mv643xx_eth_probe(struct platform_device *pdev)
          * Zero copy can only work if we use Discovery II memory. Else, we will
          * have to map the buffers to ISA memory which is only 16 MB
          */
-        dev->features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_HW_CSUM;
+        dev->features = NETIF_F_SG | NETIF_F_IP_CSUM;
 #endif
 #endif