e1000: fix unmap bug
Jesse Brandeburg [Tue, 3 Mar 2009 00:03:21 +0000 (16:03 -0800)]
This is in reference to the issue shown in kerneloops (search e1000 unmap)

The e1000 transmit code was calling pci_unmap_page on dma handles that it
might have called pci_map_single on.

Same bug as e1000e

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>

drivers/net/e1000/e1000_main.c

index 61b56ca..1f390ce 100644 (file)
@@ -2049,14 +2049,10 @@ void e1000_free_all_tx_resources(struct e1000_adapter *adapter)
 static void e1000_unmap_and_free_tx_resource(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;
        }
@@ -2907,16 +2903,24 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
                        unsigned int mss)
 {
        struct e1000_hw *hw = &adapter->hw;
-       struct e1000_buffer *buffer_info;
-       unsigned int len = skb->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;
-       len -= skb->data_len;
+       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");
+               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);
                /* Workaround for Controller erratum --
                 * descriptor for non-tso packet in a linear SKB that follows a
@@ -2949,11 +2953,7 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
                        size -= 4;
 
                buffer_info->length = size;
-               buffer_info->dma =
-                       pci_map_single(adapter->pdev,
-                               skb->data + offset,
-                               size,
-                               PCI_DMA_TODEVICE);
+               buffer_info->dma = map + offset;
                buffer_info->time_stamp = jiffies;
                buffer_info->next_to_watch = i;
 
@@ -2968,9 +2968,11 @@ 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);
                        /* Workaround for premature desc write-backs
@@ -2986,12 +2988,7 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
                                size -= 4;
 
                        buffer_info->length = size;
-                       buffer_info->dma =
-                               pci_map_page(adapter->pdev,
-                                       frag->page,
-                                       offset,
-                                       size,
-                                       PCI_DMA_TODEVICE);
+                       buffer_info->dma = map + offset;
                        buffer_info->time_stamp = jiffies;
                        buffer_info->next_to_watch = i;
 
@@ -3005,6 +3002,7 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
        i = (i == 0) ? tx_ring->count - 1 : i - 1;
        tx_ring->buffer_info[i].skb = skb;
        tx_ring->buffer_info[first].next_to_watch = i;
+       smp_wmb();
 
        return count;
 }
@@ -3844,6 +3842,11 @@ static bool e1000_clean_tx_irq(struct e1000_adapter *adapter,
                /* Detect a transmit hang in hardware, this serializes the
                 * check with the clearing of time_stamp and movement of i */
                adapter->detect_tx_hung = false;
+               /*
+                * 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))