acenic: fix the misusage of zero dma address

acenic wrongly assumes that zero is an invalid dma address (calls
dma_unmap_page for only non zero dma addresses). Zero is a valid dma
address on some architectures. The dma length can be used here.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 10 deletions

diff --git a/drivers/net/acenic.c b/drivers/net/acenic.c
index 4ae750ef1e10..e52cc3b71693 100644
--- a/drivers/net/acenic.c
+++ b/drivers/net/acenic.c
@@ -2077,18 +2077,16 @@ static inline void ace_tx_int(struct net_device *dev,
 
         do {
                 struct sk_buff *skb;
-                dma_addr_t mapping;
                 struct tx_ring_info *info;
 
                 info = ap->skb->tx_skbuff + idx;
                 skb = info->skb;
-                mapping = pci_unmap_addr(info, mapping);
 
-                if (mapping) {
-                        pci_unmap_page(ap->pdev, mapping,
+                if (dma_unmap_len(info, maplen)) {
+                        pci_unmap_page(ap->pdev, dma_unmap_addr(info, mapping),
                                        pci_unmap_len(info, maplen),
                                        PCI_DMA_TODEVICE);
-                        pci_unmap_addr_set(info, mapping, 0);
+                        dma_unmap_len_set(info, maplen, 0);
                 }
 
                 if (skb) {
@@ -2376,14 +2374,12 @@ static int ace_close(struct net_device *dev)
 
         for (i = 0; i < ACE_TX_RING_ENTRIES(ap); i++) {
                 struct sk_buff *skb;
-                dma_addr_t mapping;
                 struct tx_ring_info *info;
 
                 info = ap->skb->tx_skbuff + i;
                 skb = info->skb;
-                mapping = pci_unmap_addr(info, mapping);
 
-                if (mapping) {
+                if (dma_unmap_len(info, maplen)) {
                         if (ACE_IS_TIGON_I(ap)) {
                                 /* NB: TIGON_1 is special, tx_ring is in io space */
                                 struct tx_desc __iomem *tx;
@@ -2394,10 +2390,10 @@ static int ace_close(struct net_device *dev)
                         } else
                                 memset(ap->tx_ring + i, 0,
                                        sizeof(struct tx_desc));
-                        pci_unmap_page(ap->pdev, mapping,
+                        pci_unmap_page(ap->pdev, dma_unmap_addr(info, mapping),
                                        pci_unmap_len(info, maplen),
                                        PCI_DMA_TODEVICE);
-                        pci_unmap_addr_set(info, mapping, 0);
+                        dma_unmap_len_set(info, maplen, 0);
                 }
                 if (skb) {
                         dev_kfree_skb(skb);