Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / net / 6lowpan / nhc.h

diff --git a/kernel/net/6lowpan/nhc.h b/kernel/net/6lowpan/nhc.h
new file mode 100644 (file)
index 0000000..ed44938
--- /dev/null
+++ b/kernel/net/6lowpan/nhc.h
@@ -0,0 +1,146 @@
+#ifndef __6LOWPAN_NHC_H
+#define __6LOWPAN_NHC_H
+
+#include <linux/skbuff.h>
+#include <linux/rbtree.h>
+#include <linux/module.h>
+
+#include <net/6lowpan.h>
+#include <net/ipv6.h>
+
+#define LOWPAN_NHC_MAX_ID_LEN  1
+
+/**
+ * LOWPAN_NHC - helper macro to generate nh id fields and lowpan_nhc struct
+ *
+ * @__nhc: variable name of the lowpan_nhc struct.
+ * @_name: const char * of common header compression name.
+ * @_nexthdr: ipv6 nexthdr field for the header compression.
+ * @_nexthdrlen: ipv6 nexthdr len for the reserved space.
+ * @_idsetup: callback to setup id and mask values.
+ * @_idlen: len for the next header id and mask, should be always the same.
+ * @_uncompress: callback for uncompression call.
+ * @_compress: callback for compression call.
+ */
+#define LOWPAN_NHC(__nhc, _name, _nexthdr,     \
+                  _hdrlen, _idsetup, _idlen,   \
+                  _uncompress, _compress)      \
+static u8 __nhc##_val[_idlen];                 \
+static u8 __nhc##_mask[_idlen];                        \
+static struct lowpan_nhc __nhc = {             \
+       .name           = _name,                \
+       .nexthdr        = _nexthdr,             \
+       .nexthdrlen     = _hdrlen,              \
+       .id             = __nhc##_val,          \
+       .idmask         = __nhc##_mask,         \
+       .idlen          = _idlen,               \
+       .idsetup        = _idsetup,             \
+       .uncompress     = _uncompress,          \
+       .compress       = _compress,            \
+}
+
+#define module_lowpan_nhc(__nhc)               \
+static int __init __nhc##_init(void)           \
+{                                              \
+       return lowpan_nhc_add(&(__nhc));        \
+}                                              \
+module_init(__nhc##_init);                     \
+static void __exit __nhc##_exit(void)          \
+{                                              \
+       lowpan_nhc_del(&(__nhc));               \
+}                                              \
+module_exit(__nhc##_exit);
+
+/**
+ * struct lowpan_nhc - hold 6lowpan next hdr compression ifnformation
+ *
+ * @node: holder for the rbtree.
+ * @name: name of the specific next header compression
+ * @nexthdr: next header value of the protocol which should be compressed.
+ * @nexthdrlen: ipv6 nexthdr len for the reserved space.
+ * @id: array for nhc id. Note this need to be in network byteorder.
+ * @mask: array for nhc id mask. Note this need to be in network byteorder.
+ * @len: the length of the next header id and mask.
+ * @setup: callback to setup fill the next header id value and mask.
+ * @compress: callback to do the header compression.
+ * @uncompress: callback to do the header uncompression.
+ */
+struct lowpan_nhc {
+       struct rb_node  node;
+       const char      *name;
+       const u8        nexthdr;
+       const size_t    nexthdrlen;
+       u8              *id;
+       u8              *idmask;
+       const size_t    idlen;
+
+       void            (*idsetup)(struct lowpan_nhc *nhc);
+       int             (*uncompress)(struct sk_buff *skb, size_t needed);
+       int             (*compress)(struct sk_buff *skb, u8 **hc_ptr);
+};
+
+/**
+ * lowpan_nhc_by_nexthdr - return the 6lowpan nhc by ipv6 nexthdr.
+ *
+ * @nexthdr: ipv6 nexthdr value.
+ */
+struct lowpan_nhc *lowpan_nhc_by_nexthdr(u8 nexthdr);
+
+/**
+ * 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.
+ *
+ * @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);
+
+/**
+ * lowpan_nhc_do_compression - calling compress callback for nhc
+ *
+ * @skb: skb of 6LoWPAN header to read nhc and replace header.
+ * @hdr: ipv6hdr to set the nexthdr value
+ * @hc_ptr: pointer for 6LoWPAN header which should increment at the end of
+ *         replaced header.
+ */
+int lowpan_nhc_do_compression(struct sk_buff *skb, const struct ipv6hdr *hdr,
+                             u8 **hc_ptr);
+
+/**
+ * lowpan_nhc_do_uncompression - calling uncompress callback for nhc
+ *
+ * @nhc: 6LoWPAN nhc context, get by lowpan_nhc_by_ functions.
+ * @skb: skb of 6LoWPAN header, skb->data should be pointed to nhc id value.
+ * @dev: netdevice for print logging information.
+ * @hdr: ipv6hdr for setting nexthdr value.
+ */
+int lowpan_nhc_do_uncompression(struct sk_buff *skb, struct net_device *dev,
+                               struct ipv6hdr *hdr);
+
+/**
+ * lowpan_nhc_add - register a next header compression to framework
+ *
+ * @nhc: nhc which should be add.
+ */
+int lowpan_nhc_add(struct lowpan_nhc *nhc);
+
+/**
+ * lowpan_nhc_del - delete a next header compression from framework
+ *
+ * @nhc: nhc which should be delete.
+ */
+void lowpan_nhc_del(struct lowpan_nhc *nhc);
+
+/**
+ * lowpan_nhc_init - adding all default nhcs
+ */
+void lowpan_nhc_init(void);
+
+#endif /* __6LOWPAN_NHC_H */