/* Check if we provide the nhc format for nexthdr and compression
* functionality. If not nexthdr is handled inline and not compressed.
*/
- ret = lowpan_nhc_check_compression(skb, hdr, &hc_ptr, &iphc0);
- if (ret < 0)
- return ret;
+ ret = lowpan_nhc_check_compression(skb, hdr, &hc_ptr);
+ if (ret == -ENOENT)
+ lowpan_push_hc_data(&hc_ptr, &hdr->nexthdr,
+ sizeof(hdr->nexthdr));
+ else
+ iphc0 |= LOWPAN_IPHC_NH_C;
/* Hop limit
* if 1: compress, encoding is 01
}
int lowpan_nhc_check_compression(struct sk_buff *skb,
- const struct ipv6hdr *hdr, u8 **hc_ptr,
- u8 *iphc0)
+ const struct ipv6hdr *hdr, u8 **hc_ptr)
{
struct lowpan_nhc *nhc;
+ int ret = 0;
spin_lock_bh(&lowpan_nhc_lock);
nhc = lowpan_nexthdr_nhcs[hdr->nexthdr];
- if (nhc && nhc->compress)
- *iphc0 |= LOWPAN_IPHC_NH_C;
- else
- lowpan_push_hc_data(hc_ptr, &hdr->nexthdr,
- sizeof(hdr->nexthdr));
+ if (!(nhc && nhc->compress))
+ ret = -ENOENT;
spin_unlock_bh(&lowpan_nhc_lock);
- return 0;
+ return ret;
}
int lowpan_nhc_do_compression(struct sk_buff *skb, const struct ipv6hdr *hdr,
/**
* lowpan_nhc_check_compression - checks if we support compression format. If
- * we support the nhc by nexthdr field, the 6LoWPAN iphc NHC bit will be
- * set. If we don't support nexthdr will be added as inline data to the
- * 6LoWPAN header.
+ * we support the nhc by nexthdr field, the function will return 0. If we
+ * don't support the nhc by nexthdr this function will return -ENOENT.
*
* @skb: skb of 6LoWPAN header to read nhc and replace header.
* @hdr: ipv6hdr to check the nexthdr value
* @hc_ptr: pointer for 6LoWPAN header which should increment at the end of
* replaced header.
- * @iphc0: iphc0 pointer to set the 6LoWPAN NHC bit
*/
int lowpan_nhc_check_compression(struct sk_buff *skb,
- const struct ipv6hdr *hdr, u8 **hc_ptr,
- u8 *iphc0);
+ const struct ipv6hdr *hdr, u8 **hc_ptr);
/**
* lowpan_nhc_do_compression - calling compress callback for nhc