[patch] DMA unmap fix

dma_unmap_fix.patch (text/plain), 1.01 KB, created by Guo-Fu Tseng on 2011-07-20 17:27:21 UTC

diff --git a/jme.c b/jme.c
index 6b2a5e7..140aef9 100644
--- a/jme.c
+++ b/jme.c
@@ -751,20 +751,28 @@ jme_make_new_rx_buf(struct jme_adapter *jme, int i)
 	struct jme_ring *rxring = &(jme->rxring[0]);
 	struct jme_buffer_info *rxbi = rxring->bufinf + i;
 	struct sk_buff *skb;
+	dma_addr_t mapping;
 
 	skb = netdev_alloc_skb(jme->dev,
 		jme->dev->mtu + RX_EXTRA_LEN);
 	if (unlikely(!skb))
 		return -ENOMEM;
 
+	mapping = pci_map_page(jme->pdev, virt_to_page(skb->data),
+			       offset_in_page(skb->data), skb_tailroom(skb),
+			       PCI_DMA_FROMDEVICE);
+	if (unlikely(pci_dma_mapping_error(jme->pdev, mapping))) {
+		dev_kfree_skb(skb);
+		return -ENOMEM;
+	}
+
+	if (likely(rxbi->mapping))
+		pci_unmap_page(jme->pdev, rxbi->mapping,
+			       rxbi->len, PCI_DMA_FROMDEVICE);
+
 	rxbi->skb = skb;
 	rxbi->len = skb_tailroom(skb);
-	rxbi->mapping = pci_map_page(jme->pdev,
-					virt_to_page(skb->data),
-					offset_in_page(skb->data),
-					rxbi->len,
-					PCI_DMA_FROMDEVICE);
-
+	rxbi->mapping = mapping;
 	return 0;
 }