This patch series introduce the next header compression framework. Currently we support udp compression/uncompression only. This framework allow to add new next header compression formats easily. If somebody wants to add a new header compression format and some information are missing while calling compression and uncompression callbacks. Please feel free to make framework changes according these callbacks. changes since v2: - make udp nhc as module as suggested by Marcel Holtmann - fix comment header in nhc_udp.c I didn't make the lowpan_nhc declaration "const" because this will occur issues with rb_node, id and idmask array. Which will manipulated during runtime. changes since v3: - add patch 3/3 for other known rfc6282 ipv6 extension headers compression formats - add request_modules for loading nhc default compression format modules. Which was suggested by Jukka Rissanen. Thanks, this is really working. - Add rtnl_lock for lowpan_nhc_add and del since we have no synced request_modules call this could make trouble. - Move some handling out of nhc_do_compression and uncompression function. The complete handling is now inside of iphc.c and nhc_do_compression and uncompression functions is only a wrapper call for the callback. - rework some menuentries for Kconfig and compression format, they are grouped by rfc now. - move some generic handling like "skb_pull(skb, nhc->nexthdrlen);" into iphc.c. It would be great if we have something also for uncompression for the skb_cow. But this isn't possible right now. - change warning if nhc was not found to "was not found" instead isn't implemented. It isn't implemented if callbacks are NULL now. - small cleanups. changes since v4: - add spinlock for to prevent nhc from deletion while using. This can occur if nhc module is unloading while compression/uncompression. - move nhc handling for nhc compression/uncompression completely into nhc_do_compression/nhc_do_uncompression. Note about locking: We have now a spinlock nhc_lowpan_lock which prevents manipulating the nhc datastructures while using it. On receiving side it's easy to handle, at the end we check if 6lowpan nh compressed flag is set and run uncompression. On the other hand the transmit side is complicated, we check if next_hdr field is registrated and run some other compression routines, at least we do the finally nhc compression which depends on the first check if next_hdr was registrated. The kernel will crash if we remove the using module between "next_hdr check" and "do nhc compression", the lock will prevent that now. Now in the transmit path exist a little window to remove a lowpan_nhc while compression. This is exactly the part between "check if we support" and "doing compression". This is a very unlikely case, if this occurs we drop the packet while compression. Don't know how to better deal with that right now. I will try to search a better solution later. Cc: Jukka Rissanen <jukka.rissanen@xxxxxxxxxxxxxxx> Cc: Martin Townsend <mtownsend1973@xxxxxxxxx> Cc: Marcel Holtmann <marcel@xxxxxxxxxxxx> Alexander Aring (3): 6lowpan: add generic nhc layer interface 6lowpan: add udp compression via nhc layer 6lowpan: nhc: add other known rfc6282 compressions net/6lowpan/Kconfig | 60 +++++++++- net/6lowpan/Makefile | 13 ++- net/6lowpan/iphc.c | 200 ++++++--------------------------- net/6lowpan/nhc.c | 241 ++++++++++++++++++++++++++++++++++++++++ net/6lowpan/nhc.h | 146 ++++++++++++++++++++++++ net/6lowpan/nhc_rfc6282_dest.c | 27 +++++ net/6lowpan/nhc_rfc6282_frag.c | 26 +++++ net/6lowpan/nhc_rfc6282_hop.c | 26 +++++ net/6lowpan/nhc_rfc6282_ipv6.c | 26 +++++ net/6lowpan/nhc_rfc6282_mobil.c | 26 +++++ net/6lowpan/nhc_rfc6282_route.c | 26 +++++ net/6lowpan/nhc_rfc6282_udp.c | 156 ++++++++++++++++++++++++++ 12 files changed, 802 insertions(+), 171 deletions(-) create mode 100644 net/6lowpan/nhc.c create mode 100644 net/6lowpan/nhc.h create mode 100644 net/6lowpan/nhc_rfc6282_dest.c create mode 100644 net/6lowpan/nhc_rfc6282_frag.c create mode 100644 net/6lowpan/nhc_rfc6282_hop.c create mode 100644 net/6lowpan/nhc_rfc6282_ipv6.c create mode 100644 net/6lowpan/nhc_rfc6282_mobil.c create mode 100644 net/6lowpan/nhc_rfc6282_route.c create mode 100644 net/6lowpan/nhc_rfc6282_udp.c -- 2.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
