6lowpan: remove lowpan_fetch_skb_u8

[mirror_ubuntu-artful-kernel.git] / include / net / 6lowpan.h

diff --git a/include/net/6lowpan.h b/include/net/6lowpan.h
index eeae5eb58754c10869d55842271bfcb4bfa47db5..4afdbb3ab6d800bad32dde913742ad4ffb9a21c8 100644 (file)
--- a/include/net/6lowpan.h
+++ b/include/net/6lowpan.h
@@ -61,6 +61,24 @@
 #define UIP_PROTO_UDP                  17 /* ipv6 next header value for UDP */
 #define UIP_FRAGH_LEN                  8  /* ipv6 fragment header size */
 
+#define EUI64_ADDR_LEN         8
+
+#define LOWPAN_NHC_MAX_ID_LEN  1
+/* Maximum next header compression length which we currently support inclusive
+ * possible inline data.
+ */
+#define LOWPAN_NHC_MAX_HDR_LEN (sizeof(struct udphdr))
+/* Max IPHC Header len without IPv6 hdr specific inline data.
+ * Useful for getting the "extra" bytes we need at worst case compression.
+ *
+ * LOWPAN_IPHC + CID + LOWPAN_NHC_MAX_ID_LEN
+ */
+#define LOWPAN_IPHC_MAX_HEADER_LEN     (2 + 1 + LOWPAN_NHC_MAX_ID_LEN)
+/* Maximum worst case IPHC header buffer size */
+#define LOWPAN_IPHC_MAX_HC_BUF_LEN     (sizeof(struct ipv6hdr) +       \
+                                        LOWPAN_IPHC_MAX_HEADER_LEN +   \
+                                        LOWPAN_NHC_MAX_HDR_LEN)
+
 /*
  * ipv6 address based on mac
  * second bit-flip (Universe/Local) is done according RFC2464
@@ -240,7 +258,7 @@ struct lowpan_802154_cb *lowpan_802154_cb(const struct sk_buff *skb)
 #ifdef DEBUG
 /* print data in line */
 static inline void raw_dump_inline(const char *caller, char *msg,
-                                  unsigned char *buf, int len)
+                                  const unsigned char *buf, int len)
 {
        if (msg)
                pr_debug("%s():%s: ", caller, msg);
@@ -255,7 +273,7 @@ static inline void raw_dump_inline(const char *caller, char *msg,
  * ...
  */
 static inline void raw_dump_table(const char *caller, char *msg,
-                                 unsigned char *buf, int len)
+                                 const unsigned char *buf, int len)
 {
        if (msg)
                pr_debug("%s():%s:\n", caller, msg);
@@ -264,24 +282,25 @@ static inline void raw_dump_table(const char *caller, char *msg,
 }
 #else
 static inline void raw_dump_table(const char *caller, char *msg,
-                                 unsigned char *buf, int len) { }
+                                 const unsigned char *buf, int len) { }
 static inline void raw_dump_inline(const char *caller, char *msg,
-                                  unsigned char *buf, int len) { }
+                                  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;
@@ -301,14 +320,42 @@ static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data,
 
 void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype);
 
-int
-lowpan_header_decompress(struct sk_buff *skb, struct net_device *dev,
-                        const u8 *saddr, const u8 saddr_type,
-                        const u8 saddr_len, const u8 *daddr,
-                        const u8 daddr_type, const u8 daddr_len,
-                        u8 iphc0, u8 iphc1);
-int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev,
-                       unsigned short type, const void *_daddr,
-                       const void *_saddr, unsigned int len);
+/**
+ * lowpan_header_decompress - replace 6LoWPAN header with IPv6 header
+ *
+ * This function replaces the IPHC 6LoWPAN header which should be pointed at
+ * skb->data and skb_network_header, with the IPv6 header.
+ * It would be nice that the caller have the necessary headroom of IPv6 header
+ * and greatest Transport layer header, this would reduce the overhead for
+ * reallocate headroom.
+ *
+ * @skb: the buffer which should be manipulate.
+ * @dev: the lowpan net device pointer.
+ * @daddr: destination lladdr of mac header which is used for compression
+ *     methods.
+ * @saddr: source lladdr of mac header which is used for compression
+ *     methods.
+ */
+int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
+                            const void *daddr, const void *saddr);
+
+/**
+ * lowpan_header_compress - replace IPv6 header with 6LoWPAN header
+ *
+ * This function replaces the IPv6 header which should be pointed at
+ * skb->data and skb_network_header, with the IPHC 6LoWPAN header.
+ * The caller need to be sure that the sk buffer is not shared and at have
+ * at least a headroom which is smaller or equal LOWPAN_IPHC_MAX_HEADER_LEN,
+ * which is the IPHC "more bytes than IPv6 header" at worst case.
+ *
+ * @skb: the buffer which should be manipulate.
+ * @dev: the lowpan net device pointer.
+ * @daddr: destination lladdr of mac header which is used for compression
+ *     methods.
+ * @saddr: source lladdr of mac header which is used for compression
+ *     methods.
+ */
+int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
+                          const void *daddr, const void *saddr);
 
 #endif /* __6LOWPAN_H__ */