gianfar: only check headroom when FCB is needed

Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
index 44cbf26..6a38800 100644 (file)
--- a/drivers/net/gianfar.c
+++ b/drivers/net/gianfar.c
@@ -1310,8 +1310,10 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
        base = priv->tx_bd_base;
 
-       /* make space for additional header */
-       if (skb_headroom(skb) < GMAC_FCB_LEN) {
+       /* make space for additional header when fcb is needed */
+       if (((skb->ip_summed == CHECKSUM_PARTIAL) ||
+                       (priv->vlgrp && vlan_tx_tag_present(skb))) &&
+                       (skb_headroom(skb) < GMAC_FCB_LEN)) {
                struct sk_buff *skb_new;
 
                skb_new = skb_realloc_headroom(skb, GMAC_FCB_LEN);