6lowpan: remove lowpan_fetch_skb_u8

This patch removes the lowpan_fetch_skb_u8 function for getting the iphc
bytes. Instead we using the generic which has a len parameter to tell
the amount of bytes to fetch.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/6lowpan.h

@@ -287,19 +287,20 @@ static inline void raw_dump_inline(const char *caller, char *msg,
 				   const unsigned char *buf, int len) { }
 #endif
 
-static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val)
-{
-	if (unlikely(!pskb_may_pull(skb, 1)))
-		return -EINVAL;
-
-	*val = skb->data[0];
-	skb_pull(skb, 1);
-
-	return 0;
-}
-
-static inline bool lowpan_fetch_skb(struct sk_buff *skb,
-		void *data, const unsigned int len)
+/**
+ * lowpan_fetch_skb - getting inline data from 6LoWPAN header
+ *
+ * This function will pull data from sk buffer and put it into data to
+ * remove the 6LoWPAN inline data. This function returns true if the
+ * sk buffer is too small to pull the amount of data which is specified
+ * by len.
+ *
+ * @skb: the buffer where the inline data should be pulled from.
+ * @data: destination buffer for the inline data.
+ * @len: amount of data which should be pulled in bytes.
+ */
+static inline bool lowpan_fetch_skb(struct sk_buff *skb, void *data,
+				    unsigned int len)
 {
 	if (unlikely(!pskb_may_pull(skb, len)))
 		return true;

net/6lowpan/iphc.c

@@ -265,8 +265,8 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
 	raw_dump_table(__func__, "raw skb data dump uncompressed",
 		       skb->data, skb->len);
 
-	if (lowpan_fetch_skb_u8(skb, &iphc0) ||
-	    lowpan_fetch_skb_u8(skb, &iphc1))
+	if (lowpan_fetch_skb(skb, &iphc0, sizeof(iphc0)) ||
+	    lowpan_fetch_skb(skb, &iphc1, sizeof(iphc1)))
 		return -EINVAL;
 
 	/* another if the CID flag is set */