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sky2: hand receive DMA mapping failures

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If receive buffer mapping failed, then it was possible to get
stuck with unmapped receive buffer in DMA ring.

This would be an extremely rare condition because the driver had just
released the map for the last receive so it should be able to get
another map again (in soft-irq).

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
stephen hemminger 2010-02-01 13:45:41 +00:00 committed by David S. Miller
parent 1621e09402
commit 3fbd9187d0
1 changed files with 42 additions and 19 deletions
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61
drivers/net/sky2.c
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@ -1103,18 +1103,39 @@ static int sky2_rx_map_skb(struct pci_dev *pdev, struct rx_ring_info *re,
int i; int i;
re->data_addr = pci_map_single(pdev, skb->data, size, PCI_DMA_FROMDEVICE); re->data_addr = pci_map_single(pdev, skb->data, size, PCI_DMA_FROMDEVICE);
if (unlikely(pci_dma_mapping_error(pdev, re->data_addr))) if (pci_dma_mapping_error(pdev, re->data_addr))
return -EIO; goto mapping_error;
pci_unmap_len_set(re, data_size, size); pci_unmap_len_set(re, data_size, size);
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
re->frag_addr[i] = pci_map_page(pdev, skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
skb_shinfo(skb)->frags[i].page,
skb_shinfo(skb)->frags[i].page_offset, re->frag_addr[i] = pci_map_page(pdev, frag->page,
skb_shinfo(skb)->frags[i].size, frag->page_offset,
frag->size,
PCI_DMA_FROMDEVICE); PCI_DMA_FROMDEVICE);
if (pci_dma_mapping_error(pdev, re->frag_addr[i]))
goto map_page_error;
}
return 0; return 0;
map_page_error:
while (--i >= 0) {
pci_unmap_page(pdev, re->frag_addr[i],
skb_shinfo(skb)->frags[i].size,
PCI_DMA_FROMDEVICE);
}
pci_unmap_single(pdev, re->data_addr, pci_unmap_len(re, data_size),
PCI_DMA_FROMDEVICE);
mapping_error:
if (net_ratelimit())
dev_warn(&pdev->dev, "%s: rx mapping error\n",
skb->dev->name);
return -EIO;
} }
static void sky2_rx_unmap_skb(struct pci_dev *pdev, struct rx_ring_info *re) static void sky2_rx_unmap_skb(struct pci_dev *pdev, struct rx_ring_info *re)
@ -2306,30 +2327,32 @@ static struct sk_buff *receive_new(struct sky2_port *sky2,
struct rx_ring_info *re, struct rx_ring_info *re,
unsigned int length) unsigned int length)
{ {
struct sk_buff *skb, *nskb; struct sk_buff *skb;
struct rx_ring_info nre;
unsigned hdr_space = sky2->rx_data_size; unsigned hdr_space = sky2->rx_data_size;
/* Don't be tricky about reusing pages (yet) */ nre.skb = sky2_rx_alloc(sky2);
nskb = sky2_rx_alloc(sky2); if (unlikely(!nre.skb))
if (unlikely(!nskb)) goto nobuf;
return NULL;
if (sky2_rx_map_skb(sky2->hw->pdev, &nre, hdr_space))
goto nomap;
skb = re->skb; skb = re->skb;
sky2_rx_unmap_skb(sky2->hw->pdev, re); sky2_rx_unmap_skb(sky2->hw->pdev, re);
prefetch(skb->data); prefetch(skb->data);
re->skb = nskb; *re = nre;
if (sky2_rx_map_skb(sky2->hw->pdev, re, hdr_space)) {
dev_kfree_skb(nskb);
re->skb = skb;
return NULL;
}
if (skb_shinfo(skb)->nr_frags) if (skb_shinfo(skb)->nr_frags)
skb_put_frags(skb, hdr_space, length); skb_put_frags(skb, hdr_space, length);
else else
skb_put(skb, length); skb_put(skb, length);
return skb; return skb;
nomap:
dev_kfree_skb(nre.skb);
nobuf:
return NULL;
} }
/* /*