net: bcmgenet: cleanup for bcmgenet_xmit_frag()

Add frag_size = skb_frag_size(frag) and use it when needed.
Signed-off-by: NPetri Gynther <pgynther@google.com>
Acked-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/genet/bcmgenet.c

@@ -1331,6 +1331,7 @@ static int bcmgenet_xmit_frag(struct net_device *dev,
 	struct bcmgenet_priv *priv = netdev_priv(dev);
 	struct device *kdev = &priv->pdev->dev;
 	struct enet_cb *tx_cb_ptr;
+	unsigned int frag_size;
 	dma_addr_t mapping;
 	int ret;
 
@@ -1338,10 +1339,12 @@ static int bcmgenet_xmit_frag(struct net_device *dev,
 
 	if (unlikely(!tx_cb_ptr))
 		BUG();
+
 	tx_cb_ptr->skb = NULL;
 
-	mapping = skb_frag_dma_map(kdev, frag, 0,
-				   skb_frag_size(frag), DMA_TO_DEVICE);
+	frag_size = skb_frag_size(frag);
+
+	mapping = skb_frag_dma_map(kdev, frag, 0, frag_size, DMA_TO_DEVICE);
 	ret = dma_mapping_error(kdev, mapping);
 	if (ret) {
 		priv->mib.tx_dma_failed++;
@@ -1351,10 +1354,10 @@ static int bcmgenet_xmit_frag(struct net_device *dev,
 	}
 
 	dma_unmap_addr_set(tx_cb_ptr, dma_addr, mapping);
-	dma_unmap_len_set(tx_cb_ptr, dma_len, frag->size);
+	dma_unmap_len_set(tx_cb_ptr, dma_len, frag_size);
 
 	dmadesc_set(priv, tx_cb_ptr->bd_addr, mapping,
-		    (frag->size << DMA_BUFLENGTH_SHIFT) | dma_desc_flags |
+		    (frag_size << DMA_BUFLENGTH_SHIFT) | dma_desc_flags |
 		    (priv->hw_params->qtag_mask << DMA_TX_QTAG_SHIFT));
 
 	return 0;