[PATCH 3.2 109/115] qlge: Fix receive packets drop.

[Ben Hutchings]

3.2.80-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Manish Chopra <manish.chopra@xxxxxxxxxx>

[ Upstream commit 2c9a266afefe137bff06bbe0fc48b4d3b3cb348c ]

When running small packets [length < 256 bytes] traffic, packets were
being dropped due to invalid data in those packets which were
delivered by the driver upto the stack. Using pci_dma_sync_single_for_cpu
ensures copying latest and updated data into skb from the receive buffer.

Signed-off-by: Sony Chacko <sony.chacko@xxxxxxxxxx>
Signed-off-by: Manish Chopra <manish.chopra@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/qlogic/qlge/qlge_main.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

--- a/drivers/net/ethernet/qlogic/qlge/qlge_main.c
+++ b/drivers/net/ethernet/qlogic/qlge/qlge_main.c
@@ -1622,7 +1622,18 @@ static void ql_process_mac_rx_skb(struct
 		return;
 	}
 	skb_reserve(new_skb, NET_IP_ALIGN);
+
+	pci_dma_sync_single_for_cpu(qdev->pdev,
+				    dma_unmap_addr(sbq_desc, mapaddr),
+				    dma_unmap_len(sbq_desc, maplen),
+				    PCI_DMA_FROMDEVICE);
+
 	memcpy(skb_put(new_skb, length), skb->data, length);
+
+	pci_dma_sync_single_for_device(qdev->pdev,
+				       dma_unmap_addr(sbq_desc, mapaddr),
+				       dma_unmap_len(sbq_desc, maplen),
+				       PCI_DMA_FROMDEVICE);
 	skb = new_skb;
 
 	/* Frame error, so drop the packet. */