[NETBACK] Try to pull a minimum of 72 bytes into the skb data area

when receiving a packet into netback.  The previous number, 64, tended
to place a fragment boundary in the middle of the TCP header options
and led to unnecessary fragmentation in Windows <-> Windows
networking.

Signed-off-by: Steven Smith <ssmith@xensource.com>

diff --git a/drivers/xen/netback/netback.c b/drivers/xen/netback/netback.c
index 526f0fe18a45fd74c3378afbbf0e87baa4767bc1..7fcca69ed245afc808b36ab6218e16420b1b9065 100644 (file)
--- a/drivers/xen/netback/netback.c
+++ b/drivers/xen/netback/netback.c
@@ -106,7 +106,7 @@ static inline int netif_page_index(struct page *pg)
        return idx;
 }
 
-#define PKT_PROT_LEN 64
+#define PKT_PROT_LEN 72
 
 static struct pending_tx_info {
        netif_tx_request_t req;