net: Remove all uses of LL_ALLOCATED_SPACE

net: Remove all uses of LL_ALLOCATED_SPACE

The macro LL_ALLOCATED_SPACE was ill-conceived.  It applies the
alignment to the sum of needed_headroom and needed_tailroom.  As
the amount that is then reserved for head room is needed_headroom
with alignment, this means that the tail room left may be too small.

This patch replaces all uses of LL_ALLOCATED_SPACE with the macro
LL_RESERVED_SPACE and direct reference to needed_tailroom.

This also fixes the problem with needed_headroom changing between
allocating the skb and reserving the head room.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index cf64c1f..1a7d8e2 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -422,6 +422,7 @@
 	struct sk_buff *send_skb;
 	struct netpoll *np, *tmp;
 	unsigned long flags;
+	int hlen, tlen;
 	int hits = 0;
 
 	if (list_empty(&npinfo->rx_np))
@@ -479,8 +480,9 @@
 		if (tip != np->local_ip)
 			continue;
 
-		send_skb = find_skb(np, size + LL_ALLOCATED_SPACE(np->dev),
-				    LL_RESERVED_SPACE(np->dev));
+		hlen = LL_RESERVED_SPACE(np->dev);
+		tlen = np->dev->needed_tailroom;
+		send_skb = find_skb(np, size + hlen + tlen, hlen);
 		if (!send_skb)
 			continue;