RE: [PATCH net-next v2 07/10] net: fec: fec_enet_rx_queue(): replace manual VLAN header calculation with skb_vlan_eth_hdr()

[Wei Fang]

> >  drivers/net/ethernet/freescale/fec_main.c | 3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/freescale/fec_main.c
> > b/drivers/net/ethernet/freescale/fec_main.c
> > index 6b456372de9a..f238cb60aa65 100644
> > --- a/drivers/net/ethernet/freescale/fec_main.c
> > +++ b/drivers/net/ethernet/freescale/fec_main.c
> > @@ -1860,8 +1860,7 @@ fec_enet_rx_queue(struct net_device *ndev, u16
> queue_id, int budget)
> >  		    fep->bufdesc_ex &&
> >  		    (ebdp->cbd_esc & cpu_to_fec32(BD_ENET_RX_VLAN))) {
> >  			/* Push and remove the vlan tag */
> > -			struct vlan_hdr *vlan_header =
> > -					(struct vlan_hdr *) (data + ETH_HLEN);
> > +			struct vlan_ethhdr *vlan_header = skb_vlan_eth_hdr(skb);
> 
> This is not 'obviously correct', so probably the commit message needs expanding.
> 
> static inline struct vlan_ethhdr *skb_vlan_eth_hdr(const struct sk_buff *skb) {
> 	return (struct vlan_ethhdr *)skb->data; }
> 
> I can see a few lines early:
> 
> 		data = skb->data;
> 
> but what about the + ETH_HLEN?
> 

The type of vlan_header has been changed from "struct vlan_hdr *" to
"struct vlan_ethhdr *", so it is correct to use skb->data directly.

struct vlan_ethhdr {
	struct_group(addrs,
		unsigned char	h_dest[ETH_ALEN];
		unsigned char	h_source[ETH_ALEN];
	);
	__be16		h_vlan_proto;
	__be16		h_vlan_TCI;
	__be16		h_vlan_encapsulated_proto;
};