e1000e: fix unmap bug

This is in reference to https://bugzilla.redhat.com/show_bug.cgi?id=484494
Also addresses issue show in kerneloops

The e1000e transmit code was calling pci_unmap_page on dma handles that it
might have called pci_map_single on.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Acked-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 1b5a0c8..e74eb3c 100644 (file)
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -566,12 +566,10 @@ next_desc:
 static void e1000_put_txbuf(struct e1000_adapter *adapter,
                             struct e1000_buffer *buffer_info)
 {
-       if (buffer_info->dma) {
-               pci_unmap_page(adapter->pdev, buffer_info->dma,
-                              buffer_info->length, PCI_DMA_TODEVICE);
-               buffer_info->dma = 0;
-       }
+       buffer_info->dma = 0;
        if (buffer_info->skb) {
+               skb_dma_unmap(&adapter->pdev->dev, buffer_info->skb,
+                             DMA_TO_DEVICE);
                dev_kfree_skb_any(buffer_info->skb);
                buffer_info->skb = NULL;
        }
@@ -684,6 +682,11 @@ static bool e1000_clean_tx_irq(struct e1000_adapter *adapter)
                 * check with the clearing of time_stamp and movement of i
                 */
                adapter->detect_tx_hung = 0;
+               /*
+                * read barrier to make sure that the ->dma member and time
+                * stamp are updated fully
+                */
+               smp_rmb();
                if (tx_ring->buffer_info[eop].dma &&
                    time_after(jiffies, tx_ring->buffer_info[eop].time_stamp
                               + (adapter->tx_timeout_factor * HZ))
@@ -3820,30 +3823,31 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
                        unsigned int mss)
 {
        struct e1000_ring *tx_ring = adapter->tx_ring;
-       struct e1000_buffer *buffer_info;
-       unsigned int len = skb->len - skb->data_len;
-       unsigned int offset = 0, size, count = 0, i;
+       unsigned int len = skb_headlen(skb);
+       unsigned int offset, size, count = 0, i;
        unsigned int f;
+       dma_addr_t map;
 
        i = tx_ring->next_to_use;
 
+       if (skb_dma_map(&adapter->pdev->dev, skb, DMA_TO_DEVICE)) {
+               dev_err(&adapter->pdev->dev, "TX DMA map failed\n");
+               adapter->tx_dma_failed++;
+               dev_kfree_skb(skb);
+               return -2;
+       }
+
+       map = skb_shinfo(skb)->dma_maps[0];
+       offset = 0;
+
        while (len) {
-               buffer_info = &tx_ring->buffer_info[i];
+               struct e1000_buffer *buffer_info = &tx_ring->buffer_info[i];
                size = min(len, max_per_txd);
 
                buffer_info->length = size;
                /* set time_stamp *before* dma to help avoid a possible race */
                buffer_info->time_stamp = jiffies;
-               buffer_info->dma =
-                       pci_map_single(adapter->pdev,
-                               skb->data + offset,
-                               size,
-                               PCI_DMA_TODEVICE);
-               if (pci_dma_mapping_error(adapter->pdev, buffer_info->dma)) {
-                       dev_err(&adapter->pdev->dev, "TX DMA map failed\n");
-                       adapter->tx_dma_failed++;
-                       return -1;
-               }
+               buffer_info->dma = map + offset;
                buffer_info->next_to_watch = i;
 
                len -= size;
@@ -3859,28 +3863,17 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
 
                frag = &skb_shinfo(skb)->frags[f];
                len = frag->size;
-               offset = frag->page_offset;
+               map = skb_shinfo(skb)->dma_maps[f + 1];
+               offset = 0;
 
                while (len) {
+                       struct e1000_buffer *buffer_info;
                        buffer_info = &tx_ring->buffer_info[i];
                        size = min(len, max_per_txd);
 
                        buffer_info->length = size;
                        buffer_info->time_stamp = jiffies;
-                       buffer_info->dma =
-                               pci_map_page(adapter->pdev,
-                                       frag->page,
-                                       offset,
-                                       size,
-                                       PCI_DMA_TODEVICE);
-                       if (pci_dma_mapping_error(adapter->pdev,
-                                                 buffer_info->dma)) {
-                               dev_err(&adapter->pdev->dev,
-                                       "TX DMA page map failed\n");
-                               adapter->tx_dma_failed++;
-                               return -1;
-                       }
-
+                       buffer_info->dma = map + offset;
                        buffer_info->next_to_watch = i;
 
                        len -= size;
@@ -3900,6 +3893,7 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
 
        tx_ring->buffer_info[i].skb = skb;
        tx_ring->buffer_info[first].next_to_watch = i;
+       smp_wmb();
 
        return count;
 }