ixgbevf: redo dma mapping using the tx buffer info

This patch takes advantage of the dma buffer always being present in the
first descriptor and mapped as single. As such we can call dma_unmap_single
and don't need to check for DMA mapping in ixgbevf_clean_tx_irq().

In addition this patch makes use of the DMA API.

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 57 insertions, 37 deletions

diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index 07a501638bde..d6d06adfbc48 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -145,28 +145,25 @@ static void ixgbevf_set_ivar(struct ixgbevf_adapter *adapter, s8 direction,
 }
 
 static void ixgbevf_unmap_and_free_tx_resource(struct ixgbevf_ring *tx_ring,
-					       struct ixgbevf_tx_buffer
-					       *tx_buffer_info)
-{
-	if (tx_buffer_info->dma) {
-		if (tx_buffer_info->tx_flags & IXGBE_TX_FLAGS_MAPPED_AS_PAGE)
-			dma_unmap_page(tx_ring->dev,
-				       tx_buffer_info->dma,
-				       tx_buffer_info->length,
-				       DMA_TO_DEVICE);
-		else
+					struct ixgbevf_tx_buffer *tx_buffer)
+{
+	if (tx_buffer->skb) {
+		dev_kfree_skb_any(tx_buffer->skb);
+		if (dma_unmap_len(tx_buffer, len))
 			dma_unmap_single(tx_ring->dev,
-					 tx_buffer_info->dma,
-					 tx_buffer_info->length,
+					 dma_unmap_addr(tx_buffer, dma),
+					 dma_unmap_len(tx_buffer, len),
 					 DMA_TO_DEVICE);
-		tx_buffer_info->dma = 0;
-	}
-	if (tx_buffer_info->skb) {
-		dev_kfree_skb_any(tx_buffer_info->skb);
-		tx_buffer_info->skb = NULL;
+	} else if (dma_unmap_len(tx_buffer, len)) {
+		dma_unmap_page(tx_ring->dev,
+			       dma_unmap_addr(tx_buffer, dma),
+			       dma_unmap_len(tx_buffer, len),
+			       DMA_TO_DEVICE);
 	}
-	tx_buffer_info->time_stamp = 0;
-	/* tx_buffer_info must be completely set up in the transmit path */
+	tx_buffer->next_to_watch = NULL;
+	tx_buffer->skb = NULL;
+	dma_unmap_len_set(tx_buffer, len, 0);
+	/* tx_buffer must be completely set up in the transmit path */
 }
 
 #define IXGBE_MAX_TXD_PWR	14
@@ -221,8 +218,18 @@ static bool ixgbevf_clean_tx_irq(struct ixgbevf_q_vector *q_vector,
 		total_bytes += tx_buffer->bytecount;
 		total_packets += tx_buffer->gso_segs;
 
+		/* free the skb */
+		dev_kfree_skb_any(tx_buffer->skb);
+
+		/* unmap skb header data */
+		dma_unmap_single(tx_ring->dev,
+				 dma_unmap_addr(tx_buffer, dma),
+				 dma_unmap_len(tx_buffer, len),
+				 DMA_TO_DEVICE);
+
 		/* clear tx_buffer data */
-		ixgbevf_unmap_and_free_tx_resource(tx_ring, tx_buffer);
+		tx_buffer->skb = NULL;
+		dma_unmap_len_set(tx_buffer, len, 0);
 
 		/* unmap remaining buffers */
 		while (tx_desc != eop_desc) {
@@ -237,7 +244,14 @@ static bool ixgbevf_clean_tx_irq(struct ixgbevf_q_vector *q_vector,
 				tx_desc = IXGBEVF_TX_DESC(tx_ring, 0);
 			}
 
-			ixgbevf_unmap_and_free_tx_resource(tx_ring, tx_buffer);
+			/* unmap any remaining paged data */
+			if (dma_unmap_len(tx_buffer, len)) {
+				dma_unmap_page(tx_ring->dev,
+					       dma_unmap_addr(tx_buffer, dma),
+					       dma_unmap_len(tx_buffer, len),
+					       DMA_TO_DEVICE);
+				dma_unmap_len_set(tx_buffer, len, 0);
+			}
 		}
 
 		tx_desc->wb.status = 0;
@@ -2904,6 +2918,7 @@ static void ixgbevf_tx_csum(struct ixgbevf_ring *tx_ring,
 static int ixgbevf_tx_map(struct ixgbevf_ring *tx_ring,
 			  struct ixgbevf_tx_buffer *first)
 {
+	dma_addr_t dma;
 	struct sk_buff *skb = first->skb;
 	struct ixgbevf_tx_buffer *tx_buffer_info;
 	unsigned int len;
@@ -2921,14 +2936,16 @@ static int ixgbevf_tx_map(struct ixgbevf_ring *tx_ring,
 		tx_buffer_info = &tx_ring->tx_buffer_info[i];
 		size = min(len, (unsigned int)IXGBE_MAX_DATA_PER_TXD);
 
-		tx_buffer_info->length = size;
 		tx_buffer_info->tx_flags = first->tx_flags;
-		tx_buffer_info->dma = dma_map_single(tx_ring->dev,
-						     skb->data + offset,
-						     size, DMA_TO_DEVICE);
-		if (dma_mapping_error(tx_ring->dev, tx_buffer_info->dma))
+		dma = dma_map_single(tx_ring->dev, skb->data + offset,
+				     size, DMA_TO_DEVICE);
+		if (dma_mapping_error(tx_ring->dev, dma))
 			goto dma_error;
 
+		/* record length, and DMA address */
+		dma_unmap_len_set(tx_buffer_info, len, size);
+		dma_unmap_addr_set(tx_buffer_info, dma, dma);
+
 		len -= size;
 		total -= size;
 		offset += size;
@@ -2949,16 +2966,15 @@ static int ixgbevf_tx_map(struct ixgbevf_ring *tx_ring,
 			tx_buffer_info = &tx_ring->tx_buffer_info[i];
 			size = min(len, (unsigned int)IXGBE_MAX_DATA_PER_TXD);
 
-			tx_buffer_info->length = size;
-			tx_buffer_info->dma =
-				skb_frag_dma_map(tx_ring->dev, frag,
-						 offset, size, DMA_TO_DEVICE);
-			tx_buffer_info->tx_flags |=
-						IXGBE_TX_FLAGS_MAPPED_AS_PAGE;
-			if (dma_mapping_error(tx_ring->dev,
-					      tx_buffer_info->dma))
+			dma = skb_frag_dma_map(tx_ring->dev, frag,
+					       offset, size, DMA_TO_DEVICE);
+			if (dma_mapping_error(tx_ring->dev, dma))
 				goto dma_error;
 
+			/* record length, and DMA address */
+			dma_unmap_len_set(tx_buffer_info, len, size);
+			dma_unmap_addr_set(tx_buffer_info, dma, dma);
+
 			len -= size;
 			total -= size;
 			offset += size;
@@ -3043,11 +3059,15 @@ static void ixgbevf_tx_queue(struct ixgbevf_ring *tx_ring,
 
 	i = tx_ring->next_to_use;
 	while (count--) {
+		dma_addr_t dma;
+		unsigned int len;
+
 		tx_buffer_info = &tx_ring->tx_buffer_info[i];
+		dma = dma_unmap_addr(tx_buffer_info, dma);
+		len = dma_unmap_len(tx_buffer_info, len);
 		tx_desc = IXGBEVF_TX_DESC(tx_ring, i);
-		tx_desc->read.buffer_addr = cpu_to_le64(tx_buffer_info->dma);
-		tx_desc->read.cmd_type_len =
-			cpu_to_le32(cmd_type_len | tx_buffer_info->length);
+		tx_desc->read.buffer_addr = cpu_to_le64(dma);
+		tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type_len | len);
 		tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);
 		i++;
 		if (i == tx_ring->count)