r8169: align the IP header when there is no DMA constraint

Align the IP header when the chipset can DMA at any location (plain 0x8169).
Otherwise (0x8136/0x8168) obey the constraint imposed by the hardware.

This patch complements the previous alignment rework done for copybreak.

Original idea from Philip Craig <philipc@snapgear.com>

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Philip Craig <philipc@snapgear.com>
Cc: Mike Isely <isely@pobox.com>
Cc: Edward Hsu <edward_hsu@realtek.com.tw>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index d8862cd84f3d..1942bf7843aa 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -1415,7 +1415,7 @@ static const struct rtl_cfg_info {
         [RTL_CFG_0] = {
                 .hw_start       = rtl_hw_start_8169,
                 .region         = 1,
-                .align          = 2,
+                .align          = 0,
                 .intr_event     = SYSErr | LinkChg | RxOverflow |
                                   RxFIFOOver | TxErr | TxOK | RxOK | RxErr,
                 .napi_event     = RxFIFOOver | TxErr | TxOK | RxOK | RxOverflow
@@ -2076,12 +2076,15 @@ static struct sk_buff *rtl8169_alloc_rx_skb(struct pci_dev *pdev,
 {
         struct sk_buff *skb;
         dma_addr_t mapping;
+        unsigned int pad;
 
-        skb = netdev_alloc_skb(dev, rx_buf_sz + align);
+        pad = align ? align : NET_IP_ALIGN;
+
+        skb = netdev_alloc_skb(dev, rx_buf_sz + pad);
         if (!skb)
                 goto err_out;
 
-        skb_reserve(skb, (align - 1) & (unsigned long)skb->data);
+        skb_reserve(skb, align ? ((pad - 1) & (unsigned long)skb->data) : pad);
 
         mapping = pci_map_single(pdev, skb->data, rx_buf_sz,
                                  PCI_DMA_FROMDEVICE);