ixgbe: remove skb_dma_map/unmap calls from driver

This patch removes skb_dma_map/unmap calls from the ixgbe driver due to the
fact that the calls don't work with HW IOMMU enabled systems.  The problem
is that multiple mappings will give different results when HW IOMMU is
enabled and the skb_dma_map/unmap calls only have one location to store
mappings.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 50 insertions, 14 deletions

diff --git a/drivers/net/ixgbe/ixgbe.h b/drivers/net/ixgbe/ixgbe.h
index 76b052fa364..7e35e97227b 100644
--- a/drivers/net/ixgbe/ixgbe.h
+++ b/drivers/net/ixgbe/ixgbe.h
@@ -106,6 +106,7 @@ struct ixgbe_tx_buffer {
 	unsigned long time_stamp;
 	u16 length;
 	u16 next_to_watch;
+	u16 mapped_as_page;
 };
 
 struct ixgbe_rx_buffer {
diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index 5c56f2a741f..9ba506f6ef2 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -218,10 +218,20 @@ static void ixgbe_unmap_and_free_tx_resource(struct ixgbe_adapter *adapter,
                                              struct ixgbe_tx_buffer
                                              *tx_buffer_info)
 {
-	tx_buffer_info->dma = 0;
+	if (tx_buffer_info->dma) {
+		if (tx_buffer_info->mapped_as_page)
+			pci_unmap_page(adapter->pdev,
+				       tx_buffer_info->dma,
+				       tx_buffer_info->length,
+				       PCI_DMA_TODEVICE);
+		else
+			pci_unmap_single(adapter->pdev,
+					 tx_buffer_info->dma,
+					 tx_buffer_info->length,
+					 PCI_DMA_TODEVICE);
+		tx_buffer_info->dma = 0;
+	}
 	if (tx_buffer_info->skb) {
-		skb_dma_unmap(&adapter->pdev->dev, tx_buffer_info->skb,
-		              DMA_TO_DEVICE);
 		dev_kfree_skb_any(tx_buffer_info->skb);
 		tx_buffer_info->skb = NULL;
 	}
@@ -5024,23 +5034,16 @@ static int ixgbe_tx_map(struct ixgbe_adapter *adapter,
                         struct sk_buff *skb, u32 tx_flags,
                         unsigned int first)
 {
+	struct pci_dev *pdev = adapter->pdev;
 	struct ixgbe_tx_buffer *tx_buffer_info;
 	unsigned int len;
 	unsigned int total = skb->len;
 	unsigned int offset = 0, size, count = 0, i;
 	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
 	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");
-		return 0;
-	}
-
-	map = skb_shinfo(skb)->dma_maps;
-
 	if (tx_flags & IXGBE_TX_FLAGS_FCOE)
 		/* excluding fcoe_crc_eof for FCoE */
 		total -= sizeof(struct fcoe_crc_eof);
@@ -5051,7 +5054,12 @@ static int ixgbe_tx_map(struct ixgbe_adapter *adapter,
 		size = min(len, (uint)IXGBE_MAX_DATA_PER_TXD);
 
 		tx_buffer_info->length = size;
-		tx_buffer_info->dma = skb_shinfo(skb)->dma_head + offset;
+		tx_buffer_info->mapped_as_page = false;
+		tx_buffer_info->dma = pci_map_single(pdev,
+						     skb->data + offset,
+						     size, PCI_DMA_TODEVICE);
+		if (pci_dma_mapping_error(pdev, tx_buffer_info->dma))
+			goto dma_error;
 		tx_buffer_info->time_stamp = jiffies;
 		tx_buffer_info->next_to_watch = i;
 
@@ -5072,7 +5080,7 @@ static int ixgbe_tx_map(struct ixgbe_adapter *adapter,
 
 		frag = &skb_shinfo(skb)->frags[f];
 		len = min((unsigned int)frag->size, total);
-		offset = 0;
+		offset = frag->page_offset;
 
 		while (len) {
 			i++;
@@ -5083,7 +5091,13 @@ static int ixgbe_tx_map(struct ixgbe_adapter *adapter,
 			size = min(len, (uint)IXGBE_MAX_DATA_PER_TXD);
 
 			tx_buffer_info->length = size;
-			tx_buffer_info->dma = map[f] + offset;
+			tx_buffer_info->dma = pci_map_page(adapter->pdev,
+							   frag->page,
+							   offset, size,
+							   PCI_DMA_TODEVICE);
+			tx_buffer_info->mapped_as_page = true;
+			if (pci_dma_mapping_error(pdev, tx_buffer_info->dma))
+				goto dma_error;
 			tx_buffer_info->time_stamp = jiffies;
 			tx_buffer_info->next_to_watch = i;
 
@@ -5100,6 +5114,27 @@ static int ixgbe_tx_map(struct ixgbe_adapter *adapter,
 	tx_ring->tx_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 tx_buffer_info map */
+	tx_buffer_info->dma = 0;
+	tx_buffer_info->time_stamp = 0;
+	tx_buffer_info->next_to_watch = 0;
+	count--;
+
+	/* clear timestamp and dma mappings for remaining portion of packet */
+	while (count >= 0) {
+		count--;
+		i--;
+		if (i < 0)
+			i += tx_ring->count;
+		tx_buffer_info = &tx_ring->tx_buffer_info[i];
+		ixgbe_unmap_and_free_tx_resource(adapter, tx_buffer_info);
+	}
+
+	return count;
 }
 
 static void ixgbe_tx_queue(struct ixgbe_adapter *adapter,