@@ -478,7 +478,7 @@ rx_status_loop:
while (1) {
u32 status, len;
- dma_addr_t mapping;
+ dma_addr_t mapping, new_mapping;
struct sk_buff *skb, *new_skb;
struct cp_desc *desc;
const unsigned buflen = cp->rx_buf_sz;
@@ -520,6 +520,13 @@ rx_status_loop:
goto rx_next;
}
+ new_mapping = dma_map_single(&cp->pdev->dev, new_skb->data, buflen,
+ PCI_DMA_FROMDEVICE);
+ if (dma_mapping_error(&cp->pdev->dev, new_mapping)) {
+ dev->stats.rx_dropped++;
+ goto rx_next;
+ }
+
dma_unmap_single(&cp->pdev->dev, mapping,
buflen, PCI_DMA_FROMDEVICE);
@@ -531,12 +538,11 @@ rx_status_loop:
skb_put(skb, len);
- mapping = dma_map_single(&cp->pdev->dev, new_skb->data, buflen,
- PCI_DMA_FROMDEVICE);
cp->rx_skb[rx_tail] = new_skb;
cp_rx_skb(cp, skb, desc);
rx++;
+ mapping = new_mapping;
rx_next:
cp->rx_ring[rx_tail].opts2 = 0;
@@ -716,6 +722,22 @@ static inline u32 cp_tx_vlan_tag(struct sk_buff *skb)
TxVlanTag | swab16(vlan_tx_tag_get(skb)) : 0x00;
}
+static void unwind_tx_frag_mapping(struct cp_private *cp, struct sk_buff *skb,
+ int first, int entry_last)
+{
+ int frag, index;
+ struct cp_desc *txd;
+ skb_frag_t *this_frag;
+ for (frag = 0; frag+first < entry_last; frag++) {
+ index = first+frag;
+ cp->tx_skb[index] = NULL;
+ txd = &cp->tx_ring[index];
+ this_frag = &skb_shinfo(skb)->frags[frag];
+ dma_unmap_single(&cp->pdev->dev, le64_to_cpu(txd->addr),
+ skb_frag_size(this_frag), PCI_DMA_TODEVICE);
+ }
+}
+
static netdev_tx_t cp_start_xmit (struct sk_buff *skb,
struct net_device *dev)
{
@@ -749,6 +771,9 @@ static netdev_tx_t cp_start_xmit (struct sk_buff *skb,
len = skb->len;
mapping = dma_map_single(&cp->pdev->dev, skb->data, len, PCI_DMA_TODEVICE);
+ if (dma_mapping_error(&cp->pdev->dev, mapping))
+ goto out_dma_error;
+
txd->opts2 = opts2;
txd->addr = cpu_to_le64(mapping);
wmb();
@@ -786,6 +811,9 @@ static netdev_tx_t cp_start_xmit (struct sk_buff *skb,
first_len = skb_headlen(skb);
first_mapping = dma_map_single(&cp->pdev->dev, skb->data,
first_len, PCI_DMA_TODEVICE);
+ if (dma_mapping_error(&cp->pdev->dev, first_mapping))
+ goto out_dma_error;
+
cp->tx_skb[entry] = skb;
entry = NEXT_TX(entry);
@@ -799,6 +827,11 @@ static netdev_tx_t cp_start_xmit (struct sk_buff *skb,
mapping = dma_map_single(&cp->pdev->dev,
skb_frag_address(this_frag),
len, PCI_DMA_TODEVICE);
+ if (dma_mapping_error(&cp->pdev->dev, mapping)) {
+ unwind_tx_frag_mapping(cp, skb, first_entry, entry);
+ goto out_dma_error;
+ }
+
eor = (entry == (CP_TX_RING_SIZE - 1)) ? RingEnd : 0;
ctrl = eor | len | DescOwn;
@@ -859,11 +892,16 @@ static netdev_tx_t cp_start_xmit (struct sk_buff *skb,
if (TX_BUFFS_AVAIL(cp) <= (MAX_SKB_FRAGS + 1))
netif_stop_queue(dev);
+out_unlock:
spin_unlock_irqrestore(&cp->lock, intr_flags);
cpw8(TxPoll, NormalTxPoll);
return NETDEV_TX_OK;
+out_dma_error:
+ kfree_skb(skb);
+ cp->dev->stats.tx_dropped++;
+ goto out_unlock;
}
/* Set or clear the multicast filter for this adaptor.
@@ -1054,6 +1092,10 @@ static int cp_refill_rx(struct cp_private *cp)
mapping = dma_map_single(&cp->pdev->dev, skb->data,
cp->rx_buf_sz, PCI_DMA_FROMDEVICE);
+ if (dma_mapping_error(&cp->pdev->dev, mapping)) {
+ kfree_skb(skb);
+ goto err_out;
+ }
cp->rx_skb[i] = skb;
cp->rx_ring[i].opts2 = 0;
Self explanitory dma_mapping_error addition to the 8139 driver, based on this: https://bugzilla.redhat.com/show_bug.cgi?id=947250 It showed several backtraces arising for dma_map_* usage without checking the return code on the mapping. Add the check and abort the rx/tx operation if its failed. Untested as I have no hardware and the reporter has wandered off, but seems pretty straightforward. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: "David S. Miller" <davem@davemloft.net> CC: Francois Romieu <romieu@fr.zoreil.com> --- Change notes: v2) Added stats update for tx_dropped as per Francois Romieu v3) * Updated rx patch to handle dma errors properly. Francois had pointed out that I needed to increment the rx_dropped stat there, but the problem was a bit deeper. I actually had to move the dma_mapping and error check higher in the path, so that, in the event of a failure, we could drop the received skb, and reuse its existing mapping in the rx ring. this is in line with what happens if the skb allocation fails * Updated the tx path to have a common goto for mapping failures, so we only have one location to drop the skb * Moved the unwind code into a separate helper function, as per Francois suggestion. I though it would be alot of parameter passing and not very adventageous, but on second look I think its more readable. v4) * Fix rx/tx naming error. --- drivers/net/ethernet/realtek/8139cp.c | 48 ++++++++++++++++++++++++++++++++--- 1 file changed, 45 insertions(+), 3 deletions(-)