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author | Al Viro <viro@zeniv.linux.org.uk> | 2015-04-12 05:27:19 +0300 |
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committer | Al Viro <viro@zeniv.linux.org.uk> | 2015-04-12 05:27:19 +0300 |
commit | 39c853ebfe169f187a760b34f9cbf54751bfce00 (patch) | |
tree | 2a5a741d0cff7d4f90998b31b32ff80cfccd0369 /net/6lowpan/nhc.h | |
parent | fdc81f45e9f57858da6351836507fbcf1b7583ee (diff) | |
parent | 01e97e6517053d7c0b9af5248e944a9209909cf5 (diff) | |
download | linux-39c853ebfe169f187a760b34f9cbf54751bfce00.tar.xz |
Merge branch 'for-davem' into for-next
Diffstat (limited to 'net/6lowpan/nhc.h')
-rw-r--r-- | net/6lowpan/nhc.h | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/net/6lowpan/nhc.h b/net/6lowpan/nhc.h new file mode 100644 index 000000000000..ed44938eb5de --- /dev/null +++ b/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 */ |