[PATCH net] net: bcmgenet: fix dma api length mismatch

[Eric Dumazet]

From: Eric Dumazet <eduma...@google.com>

When un-mapping skb->data in __bcmgenet_tx_reclaim(),
we must use the length that was used in original dma_map_single(),
instead of skb->len that might be bigger (includes the frags)

We simply can store skb_len into tx_cb_ptr->dma_len and use it
at unmap time.

Fixes: 1c1008c793fa ("net: bcmgenet: add main driver file")
Signed-off-by: Eric Dumazet <eduma...@google.com>
---
 drivers/net/ethernet/broadcom/genet/bcmgenet.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c 
b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index d7e01a7..6746fd0 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -1197,7 +1197,7 @@ static unsigned int __bcmgenet_tx_reclaim(struct 
net_device *dev,
                        dev->stats.tx_bytes += tx_cb_ptr->skb->len;
                        dma_unmap_single(&dev->dev,
                                         dma_unmap_addr(tx_cb_ptr, dma_addr),
-                                        tx_cb_ptr->skb->len,
+                                        dma_unmap_len(tx_cb_ptr, dma_len),
                                         DMA_TO_DEVICE);
                        bcmgenet_free_cb(tx_cb_ptr);
                } else if (dma_unmap_addr(tx_cb_ptr, dma_addr)) {
@@ -1308,7 +1308,7 @@ static int bcmgenet_xmit_single(struct net_device *dev,
        }
 
        dma_unmap_addr_set(tx_cb_ptr, dma_addr, mapping);
-       dma_unmap_len_set(tx_cb_ptr, dma_len, skb->len);
+       dma_unmap_len_set(tx_cb_ptr, dma_len, skb_len);
        length_status = (skb_len << DMA_BUFLENGTH_SHIFT) | dma_desc_flags |
                        (priv->hw_params->qtag_mask << DMA_TX_QTAG_SHIFT) |
                        DMA_TX_APPEND_CRC;