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p54pci: update receive dma buffers before and after processing

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Documentation/DMA-API-HOWTO.txt states:

"DMA transfers need to be synced properly in order for
the cpu and device to see the most uptodate and correct
copy of the DMA buffer."

Cc: <stable@kernel.org>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Christian Lamparter 2011-02-11 01:48:42 +01:00 committed by John W. Linville
parent 4f919a3bc5
commit 0bf719dfde
1 changed files with 9 additions and 5 deletions
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14
drivers/net/wireless/p54/p54pci.c
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@ -199,6 +199,7 @@ static void p54p_check_rx_ring(struct ieee80211_hw *dev, u32 *index,
while (i != idx) {
u16 len;
struct sk_buff *skb;
dma_addr_t dma_addr;
desc = &ring[i];
len = le16_to_cpu(desc->len);
skb = rx_buf[i];
@ -216,17 +217,20 @@ static void p54p_check_rx_ring(struct ieee80211_hw *dev, u32 *index,
len = priv->common.rx_mtu;
}
dma_addr = le32_to_cpu(desc->host_addr);
pci_dma_sync_single_for_cpu(priv->pdev, dma_addr,
priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE);
skb_put(skb, len);
if (p54_rx(dev, skb)) {
pci_unmap_single(priv->pdev,
le32_to_cpu(desc->host_addr),
priv->common.rx_mtu + 32,
PCI_DMA_FROMDEVICE);
pci_unmap_single(priv->pdev, dma_addr,
priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE);
rx_buf[i] = NULL;
desc->host_addr = 0;
desc->host_addr = cpu_to_le32(0);
} else {
skb_trim(skb, 0);
pci_dma_sync_single_for_device(priv->pdev, dma_addr,
priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE);
desc->len = cpu_to_le16(priv->common.rx_mtu + 32);
}