igb: remove use of skb_dma_map from driver

This change removes skb_dma_map/unmap calls from the igb driver due to the
fact that the call is incompatible with iommu enabled kernels.  In order to
prevent warnings about using the wrong unmap call I have added a
mapped_as_page value to the buffer_info structure to track if the mapped
region is a page or a buffer.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 56 insertions, 18 deletions

diff --git a/drivers/net/igb/igb.h b/drivers/net/igb/igb.h
index c458d9b188ba..b1c1eb88893f 100644
--- a/drivers/net/igb/igb.h
+++ b/drivers/net/igb/igb.h
@@ -137,12 +137,13 @@ struct igb_buffer {
                         unsigned long time_stamp;
                         u16 length;
                         u16 next_to_watch;
+                        u16 mapped_as_page;
                 };
                 /* RX */
                 struct {
                         struct page *page;
-                        u64 page_dma;
-                        unsigned int page_offset;
+                        dma_addr_t page_dma;
+                        u16 page_offset;
                 };
         };
 };
diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index bb1a6eeade06..e57b32d3fde4 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -2654,16 +2654,27 @@ static void igb_free_all_tx_resources(struct igb_adapter *adapter)
 void igb_unmap_and_free_tx_resource(struct igb_ring *tx_ring,
                                     struct igb_buffer *buffer_info)
 {
-        buffer_info->dma = 0;
+        if (buffer_info->dma) {
+                if (buffer_info->mapped_as_page)
+                        pci_unmap_page(tx_ring->pdev,
+                                        buffer_info->dma,
+                                        buffer_info->length,
+                                        PCI_DMA_TODEVICE);
+                else
+                        pci_unmap_single(tx_ring->pdev,
+                                        buffer_info->dma,
+                                        buffer_info->length,
+                                        PCI_DMA_TODEVICE);
+                buffer_info->dma = 0;
+        }
         if (buffer_info->skb) {
-                skb_dma_unmap(&tx_ring->pdev->dev,
-                              buffer_info->skb,
-                              DMA_TO_DEVICE);
                 dev_kfree_skb_any(buffer_info->skb);
                 buffer_info->skb = NULL;
         }
         buffer_info->time_stamp = 0;
-        /* buffer_info must be completely set up in the transmit path */
+        buffer_info->length = 0;
+        buffer_info->next_to_watch = 0;
+        buffer_info->mapped_as_page = false;
 }
 
 /**
@@ -3561,24 +3572,19 @@ static inline int igb_tx_map_adv(struct igb_ring *tx_ring, struct sk_buff *skb,
         unsigned int len = skb_headlen(skb);
         unsigned int count = 0, i;
         unsigned int f;
-        dma_addr_t *map;
 
         i = tx_ring->next_to_use;
 
-        if (skb_dma_map(&pdev->dev, skb, DMA_TO_DEVICE)) {
-                dev_err(&pdev->dev, "TX DMA map failed\n");
-                return 0;
-        }
-
-        map = skb_shinfo(skb)->dma_maps;
-
         buffer_info = &tx_ring->buffer_info[i];
         BUG_ON(len >= IGB_MAX_DATA_PER_TXD);
         buffer_info->length = len;
         /* set time_stamp *before* dma to help avoid a possible race */
         buffer_info->time_stamp = jiffies;
         buffer_info->next_to_watch = i;
-        buffer_info->dma = skb_shinfo(skb)->dma_head;
+        buffer_info->dma = pci_map_single(pdev, skb->data, len,
+                                          PCI_DMA_TODEVICE);
+        if (pci_dma_mapping_error(pdev, buffer_info->dma))
+                goto dma_error;
 
         for (f = 0; f < skb_shinfo(skb)->nr_frags; f++) {
                 struct skb_frag_struct *frag;
@@ -3595,7 +3601,15 @@ static inline int igb_tx_map_adv(struct igb_ring *tx_ring, struct sk_buff *skb,
                 buffer_info->length = len;
                 buffer_info->time_stamp = jiffies;
                 buffer_info->next_to_watch = i;
-                buffer_info->dma = map[count];
+                buffer_info->mapped_as_page = true;
+                buffer_info->dma = pci_map_page(pdev,
+                                                frag->page,
+                                                frag->page_offset,
+                                                len,
+                                                PCI_DMA_TODEVICE);
+                if (pci_dma_mapping_error(pdev, buffer_info->dma))
+                        goto dma_error;
+
                 count++;
         }
 
@@ -3603,6 +3617,29 @@ static inline int igb_tx_map_adv(struct igb_ring *tx_ring, struct sk_buff *skb,
         tx_ring->buffer_info[first].next_to_watch = i;
 
         return ++count;
+
+dma_error:
+        dev_err(&pdev->dev, "TX DMA map failed\n");
+
+        /* clear timestamp and dma mappings for failed buffer_info mapping */
+        buffer_info->dma = 0;
+        buffer_info->time_stamp = 0;
+        buffer_info->length = 0;
+        buffer_info->next_to_watch = 0;
+        buffer_info->mapped_as_page = false;
+        count--;
+
+        /* clear timestamp and dma mappings for remaining portion of packet */
+        while (count >= 0) {
+                count--;
+                i--;
+                if (i < 0)
+                        i += tx_ring->count;
+                buffer_info = &tx_ring->buffer_info[i];
+                igb_unmap_and_free_tx_resource(tx_ring, buffer_info);
+        }
+
+        return 0;
 }
 
 static inline void igb_tx_queue_adv(struct igb_ring *tx_ring,
@@ -3755,7 +3792,7 @@ netdev_tx_t igb_xmit_frame_ring_adv(struct sk_buff *skb,
          * has occured and we need to rewind the descriptor queue
          */
         count = igb_tx_map_adv(tx_ring, skb, first);
-        if (count <= 0) {
+        if (!count) {
                 dev_kfree_skb_any(skb);
                 tx_ring->buffer_info[first].time_stamp = 0;
                 tx_ring->next_to_use = first;