6LoWPAN: add fragmentation support
This patch adds support for frame fragmentation.
Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/6lowpan.h b/net/ieee802154/6lowpan.h
index 5d8cf80..5d2e5a0 100644
--- a/net/ieee802154/6lowpan.h
+++ b/net/ieee802154/6lowpan.h
@@ -159,6 +159,24 @@
#define LOWPAN_DISPATCH_FRAG1 0xc0 /* 11000xxx */
#define LOWPAN_DISPATCH_FRAGN 0xe0 /* 11100xxx */
+#define LOWPAN_DISPATCH_MASK 0xf8 /* 11111000 */
+
+#define LOWPAN_FRAG_TIMEOUT (HZ * 60) /* time-out 60 sec */
+
+#define LOWPAN_FRAG1_HEAD_SIZE 0x4
+#define LOWPAN_FRAGN_HEAD_SIZE 0x5
+
+/*
+ * According IEEE802.15.4 standard:
+ * - MTU is 127 octets
+ * - maximum MHR size is 37 octets
+ * - MFR size is 2 octets
+ *
+ * so minimal payload size that we may guarantee is:
+ * MTU - MHR - MFR = 88 octets
+ */
+#define LOWPAN_FRAG_SIZE 88
+
/*
* Values of fields within the IPHC encoding first byte
* (C stands for compressed and I for inline)