sh_eth: advance 'rxdesc' later in sh_eth_ring_format()

BugLink: http://bugs.launchpad.net/bugs/1573034
[ Upstream commit d0ba913488dc8c55d1880f5ed34f096dc45fb05d ]

Iff dma_map_single() fails, 'rxdesc'  should point  to the last filled RX
descriptor, so  that it can be marked as the last one, however the driver
would have  already  advanced it by that time. In order to fix that, only
fill  an RX descriptor  once all the data for it is ready.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index a1702f4ac6ff53539df8be02209e9ec8f611f1c3..36fc9427418f325b433349e08700801387b412ba 100644 (file)
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -1185,11 +1185,8 @@ static void sh_eth_ring_format(struct net_device *ndev)
                        break;
                sh_eth_set_receive_align(skb);
 
-               /* RX descriptor */
-               rxdesc = &mdp->rx_ring[i];
                /* The size of the buffer is a multiple of 32 bytes. */
                buf_len = ALIGN(mdp->rx_buf_sz, 32);
-               rxdesc->len = cpu_to_edmac(mdp, buf_len << 16);
                dma_addr = dma_map_single(&ndev->dev, skb->data, buf_len,
                                          DMA_FROM_DEVICE);
                if (dma_mapping_error(&ndev->dev, dma_addr)) {
@@ -1197,6 +1194,10 @@ static void sh_eth_ring_format(struct net_device *ndev)
                        break;
                }
                mdp->rx_skbuff[i] = skb;
+
+               /* RX descriptor */
+               rxdesc = &mdp->rx_ring[i];
+               rxdesc->len = cpu_to_edmac(mdp, buf_len << 16);
                rxdesc->addr = cpu_to_edmac(mdp, dma_addr);
                rxdesc->status = cpu_to_edmac(mdp, RD_RACT | RD_RFP);