[PATCH] xen-netback: use netdev_alloc_skb_ip_align

[Stephen Hemminger <stephen@networkplumber.org>]

Use standard helper function to allocate and align received packet.
Compile tested only

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>


--- a/drivers/net/xen-netback/netback.c	2013-03-07 18:12:52.825300956 -0800
+++ b/drivers/net/xen-netback/netback.c	2013-03-20 12:09:09.052034865 -0700
@@ -1357,8 +1357,8 @@ static unsigned xen_netbk_tx_build_gops(
 			    ret < MAX_SKB_FRAGS) ?
 			PKT_PROT_LEN : txreq.size;
 
-		skb = alloc_skb(data_len + NET_SKB_PAD + NET_IP_ALIGN,
-				GFP_ATOMIC | __GFP_NOWARN);
+		skb = __netdev_alloc_skb_ip_align(vif->dev, data_len,
+						  GFP_ATOMIC | __GFP_NOWARN);
 		if (unlikely(skb == NULL)) {
 			netdev_dbg(vif->dev,
 				   "Can't allocate a skb in start_xmit.\n");
@@ -1366,9 +1366,6 @@ static unsigned xen_netbk_tx_build_gops(
 			break;
 		}
 
-		/* Packets passed to netif_rx() must have some headroom. */
-		skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
-
 		if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) {
 			struct xen_netif_extra_info *gso;
 			gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1];