Commit 93c1285c authored by Li Yang's avatar Li Yang Committed by David S. Miller
Browse files

gianfar: reallocate skb when headroom is not enough for fcb 



Gianfar uses a hardware header FCB for offloading.  However when used
with bridging or IP forwarding, TX skb might not have enough headroom
for the FCB.  Reallocate skb for such cases.

Signed-off-by: default avatarLi Yang <leoli@freescale.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8ca51986

drivers/net/gianfar.c

+21 −10
Original line number Diff line number Diff line
@@ -1239,10 +1239,19 @@ static int gfar_enet_open(struct net_device *dev) 
	return err;

}



static inline struct txfcb *gfar_add_fcb(struct sk_buff *skb)

static inline struct txfcb *gfar_add_fcb(struct sk_buff **skbp)

{

	struct txfcb *fcb = (struct txfcb *)skb_push (skb, GMAC_FCB_LEN);

	struct txfcb *fcb;

	struct sk_buff *skb = *skbp;



	if (unlikely(skb_headroom(skb) < GMAC_FCB_LEN)) {

		struct sk_buff *old_skb = skb;

		skb = skb_realloc_headroom(old_skb, GMAC_FCB_LEN);

		if (!skb)

			return NULL;

		dev_kfree_skb_any(old_skb);

	}

	fcb = (struct txfcb *)skb_push(skb, GMAC_FCB_LEN);

	cacheable_memzero(fcb, GMAC_FCB_LEN);



	return fcb;
@@ -1363,19 +1372,21 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) 


	/* Set up checksumming */

	if (CHECKSUM_PARTIAL == skb->ip_summed) {

		fcb = gfar_add_fcb(skb);

		fcb = gfar_add_fcb(&skb);

		if (likely(fcb != NULL)) {

			lstatus |= BD_LFLAG(TXBD_TOE);

			gfar_tx_checksum(skb, fcb);

		}

	}



	if (priv->vlgrp && vlan_tx_tag_present(skb)) {

		if (unlikely(NULL == fcb)) {

			fcb = gfar_add_fcb(skb);

		if (unlikely(NULL == fcb))

			fcb = gfar_add_fcb(&skb);

		if (likely(fcb != NULL)) {

			lstatus |= BD_LFLAG(TXBD_TOE);

		}



			gfar_tx_vlan(skb, fcb);

		}

	}



	/* setup the TxBD length and buffer pointer for the first BD */

	priv->tx_skbuff[priv->skb_curtx] = skb;