[ PATCH v1 2/2] ibmveth: Identify ingress large send packets.

[David Wilder <dwilder@us.ibm.com>]

Ingress large send packets are identified by either:
The IBMVETH_RXQ_LRG_PKT flag in the receive buffer
or with a -1 placed in the ip header checksum.
The method used depends on firmware version.

Signed-off-by: David Wilder <dwilder@us.ibm.com>
Reviewed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Reviewed-by: Cristobal Forno <cris.forno@ibm.com>
Reviewed-by: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>
---
 drivers/net/ethernet/ibm/ibmveth.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c
index 3935a7e..e357cbe 100644
--- a/drivers/net/ethernet/ibm/ibmveth.c
+++ b/drivers/net/ethernet/ibm/ibmveth.c
@@ -1349,6 +1349,7 @@ static int ibmveth_poll(struct napi_struct *napi, int budget)
 			int offset = ibmveth_rxq_frame_offset(adapter);
 			int csum_good = ibmveth_rxq_csum_good(adapter);
 			int lrg_pkt = ibmveth_rxq_large_packet(adapter);
+			__sum16 iph_check = 0;
 
 			skb = ibmveth_rxq_get_buffer(adapter);
 
@@ -1385,7 +1386,17 @@ static int ibmveth_poll(struct napi_struct *napi, int budget)
 			skb_put(skb, length);
 			skb->protocol = eth_type_trans(skb, netdev);
 
-			if (length > netdev->mtu + ETH_HLEN) {
+			/* PHYP without PLSO support places a -1 in the ip
+			 * checksum for large send frames.
+			 */
+			if (be16_to_cpu(skb->protocol) == ETH_P_IP) {
+				struct iphdr *iph = (struct iphdr *)skb->data;
+
+				iph_check = iph->check;
+			}
+
+			if ((length > netdev->mtu + ETH_HLEN) ||
+			    lrg_pkt || iph_check == 0xffff) {
 				ibmveth_rx_mss_helper(skb, mss, lrg_pkt);
 				adapter->rx_large_packets++;
 			}
-- 
1.8.3.1