alistair23-linux/include/net/sctp
Marcelo Ricardo Leitner 90017accff sctp: Add GSO support
SCTP has this pecualiarity that its packets cannot be just segmented to
(P)MTU. Its chunks must be contained in IP segments, padding respected.
So we can't just generate a big skb, set gso_size to the fragmentation
point and deliver it to IP layer.

This patch takes a different approach. SCTP will now build a skb as it
would be if it was received using GRO. That is, there will be a cover
skb with protocol headers and children ones containing the actual
segments, already segmented to a way that respects SCTP RFCs.

With that, we can tell skb_segment() to just split based on frag_list,
trusting its sizes are already in accordance.

This way SCTP can benefit from GSO and instead of passing several
packets through the stack, it can pass a single large packet.

v2:
- Added support for receiving GSO frames, as requested by Dave Miller.
- Clear skb->cb if packet is GSO (otherwise it's not used by SCTP)
- Added heuristics similar to what we have in TCP for not generating
  single GSO packets that fills cwnd.
v3:
- consider sctphdr size in skb_gso_transport_seglen()
- rebased due to 5c7cdf339a ("gso: Remove arbitrary checks for
  unsupported GSO")

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-03 19:37:21 -04:00
..
auth.h sctp: Use shash 2016-01-27 20:36:15 +08:00
checksum.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
command.h sctp: handle association restarts when the socket is closed. 2014-10-06 00:21:45 -04:00
constants.h net: sctp: Rename SCTP_XMIT_NAGLE_DELAY to SCTP_XMIT_DELAY 2014-07-22 13:32:11 -07:00
sctp.h sctp: Add GSO support 2016-06-03 19:37:21 -04:00
sm.h sctp: allow sctp_transmit_packet and others to use gfp 2016-03-13 22:29:07 -04:00
structs.h sctp: Add GSO support 2016-06-03 19:37:21 -04:00
tsnmap.h sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
ulpevent.h net: sctp: implement rfc6458, 5.3.6. SCTP_NXTINFO cmsg support 2014-07-16 14:40:03 -07:00
ulpqueue.h sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00