appletalk: Use frag list abstraction interfaces.

Signed-off-by: David S. Miller <davem@davemloft.net>

net/appletalk/ddp.c

@@ -939,6 +939,7 @@ static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset,
 				   int len, unsigned long sum)
 {
 	int start = skb_headlen(skb);
+	struct sk_buff *frag_iter;
 	int i, copy;
 
 	/* checksum stuff in header space */
@@ -977,26 +978,22 @@ static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset,
 		start = end;
 	}
 
-	if (skb_shinfo(skb)->frag_list) {
+	skb_walk_frags(skb, frag_iter) {
-		struct sk_buff *list = skb_shinfo(skb)->frag_list;
+		int end;
 
-		for (; list; list = list->next) {
+		WARN_ON(start > offset + len);
-			int end;
 
-			WARN_ON(start > offset + len);
+		end = start + frag_iter->len;
-
+		if ((copy = end - offset) > 0) {
-			end = start + list->len;
+			if (copy > len)
-			if ((copy = end - offset) > 0) {
+				copy = len;
-				if (copy > len)
+			sum = atalk_sum_skb(frag_iter, offset - start,
-					copy = len;
+					    copy, sum);
-				sum = atalk_sum_skb(list, offset - start,
+			if ((len -= copy) == 0)
-						    copy, sum);
+				return sum;
-				if ((len -= copy) == 0)
+			offset += copy;
-					return sum;
-				offset += copy;
-			}
-			start = end;
 		}
+		start = end;
 	}
 
 	BUG_ON(len > 0);