ath9k: Synchronize DMA transfer with CPU at right place
This patch does pci_dma_sync_single_for_cpu() before accessing
the header of the frame and queueing the same buffer into h/w.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath9k/recv.c b/drivers/net/wireless/ath9k/recv.c
index cc160fe..462e08c 100644
--- a/drivers/net/wireless/ath9k/recv.c
+++ b/drivers/net/wireless/ath9k/recv.c
@@ -520,6 +520,15 @@
continue;
/*
+ * Synchronize the DMA transfer with CPU before
+ * 1. accessing the frame
+ * 2. requeueing the same buffer to h/w
+ */
+ pci_dma_sync_single_for_cpu(sc->pdev, bf->bf_buf_addr,
+ sc->rx.bufsize,
+ PCI_DMA_FROMDEVICE);
+
+ /*
* If we're asked to flush receive queue, directly
* chain it back at the queue without processing it.
*/
@@ -547,10 +556,7 @@
if (!requeue_skb)
goto requeue;
- /* Sync and unmap the frame */
- pci_dma_sync_single_for_cpu(sc->pdev, bf->bf_buf_addr,
- sc->rx.bufsize,
- PCI_DMA_FROMDEVICE);
+ /* Unmap the frame */
pci_unmap_single(sc->pdev, bf->bf_buf_addr,
sc->rx.bufsize,
PCI_DMA_FROMDEVICE);
