aha/net/dccp
Gerrit Renker 361a5c1dd0 dccp: Minimise header option overhead in setting the MPS
This patch resolves a long-standing FIXME to dynamically update the Maximum
Packet Size depending on actual options usage.

It uses the flags set by the feature-negotiation infrastructure to compute
the required header option size.

Most options are fixed-size, a notable exception are Ack Vectors (required
currently only by CCID-2). These can have any length between 3 and 1020
bytes. As a result of testing, 16 bytes (2 bytes for type/length plus 14 Ack
Vector cells) have been found to be sufficient for loss-free situations.

There are currently no CCID-specific header options which may appear on data
packets, thus it is not necessary to define a corresponding CCID field as
suggested in the old comment.

Further changes:
----------------
 Adjusted the type of 'cur_mps' to match the unsigned return type of the
 function.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-02 03:07:23 -08:00
..
ccids dccp ccid-3: Fix RFC reference 2009-01-11 00:17:22 -08:00
ackvec.c dccp: Set per-connection CCIDs via socket options 2008-11-23 16:02:31 -08:00
ackvec.h dccp: Minimise header option overhead in setting the MPS 2009-03-02 03:07:23 -08:00
ccid.c dccp: Integrate the TFRC library with DCCP 2009-01-04 21:45:33 -08:00
ccid.h dccp: Clean up ccid.c after integration of CCID plugins 2009-01-04 21:43:23 -08:00
dccp.h dccp: Debugging functions for feature negotiation 2009-01-21 14:34:05 -08:00
diag.c dccp_diag: LISTEN sockets don't have CCIDs 2008-12-17 16:08:01 -08:00
feat.c dccp: Debugging functions for feature negotiation 2009-01-21 14:34:05 -08:00
feat.h dccp: Debugging functions for feature negotiation 2009-01-21 14:34:05 -08:00
input.c dccp: Integrate the TFRC library with DCCP 2009-01-04 21:45:33 -08:00
ipv4.c net: Convert TCP & DCCP hash tables to use RCU / hlist_nulls 2008-11-16 19:40:17 -08:00
ipv6.c netns xfrm: lookup in netns 2008-11-25 17:35:18 -08:00
ipv6.h Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
Kconfig dccp: Lockless integration of CCID congestion-control plugins 2009-01-04 21:42:53 -08:00
Makefile dccp: Integrate the TFRC library with DCCP 2009-01-04 21:45:33 -08:00
minisocks.c dccp: Implement both feature-local and feature-remote Sequence Window feature 2009-01-21 14:34:04 -08:00
options.c dccp: Debugging functions for feature negotiation 2009-01-21 14:34:05 -08:00
output.c dccp: Minimise header option overhead in setting the MPS 2009-03-02 03:07:23 -08:00
probe.c dccp: API to query the current TX/RX CCID 2008-11-23 16:04:59 -08:00
proto.c dccp: Implement both feature-local and feature-remote Sequence Window feature 2009-01-21 14:34:04 -08:00
sysctl.c dccp: Initialisation and type-checking of feature sysctls 2009-01-21 14:34:05 -08:00
timer.c dccp: Limit feature negotiation to connection setup phase 2008-11-12 00:42:58 -08:00