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>

1 files changed, 28 insertions, 34 deletions

diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 1b5a0c8b34c8..e74eb3c606e0 100644
--- 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;
 }