kernel/linux.git/net/dccp/ackvec.h, branch v6.12.80

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

net: dccp: Remove extern from function prototypes

2013-10-19T23:12:11+00:00

There are a mix of function prototypes with and without extern in the kernel sources. Standardize on not using extern for function prototypes. Function prototypes don't need to be written with extern. extern is assumed by the compiler. Its use is as unnecessary as using auto to declare automatic/local variables in a block. Signed-off-by: Joe Perches Signed-off-by: David S. Miller

net: Fix (nearly-)kernel-doc comments for various functions

2012-07-11T06:13:45+00:00

Fix incorrect start markers, wrapped summary lines, missing section breaks, incorrect separators, and some name mismatches. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

dccp ccid-2: Separate option parsing from CCID processing

2010-11-15T06:12:01+00:00

This patch replaces an almost identical replication of code: large parts of dccp_parse_options() re-appeared as ccid2_ackvector() in ccid2.c. Apart from the duplication, this caused two more problems: 1. CCIDs should not need to be concerned with parsing header options; 2. one can not assume that Ack Vectors appear as a contiguous area within an skb, it is legal to insert other options and/or padding in between. The current code would throw an error and stop reading in such a case. Since Ack Vectors provide CCID-specific information, they are now processed by the CCID directly, separating this functionality from the main DCCP code. Signed-off-by: Gerrit Renker

dccp ccid-2: Remove old infrastructure

2010-11-15T06:12:00+00:00

This removes * functions for which updates have been provided in the preceding patches and * the @av_vec_len field - it is no longer necessary since the buffer length is now always computed dynamically. Signed-off-by: Gerrit Renker

dccp ccid-2: Update code for the Ack Vector input/registration routine

2010-11-15T06:11:59+00:00

This patch updates the code which registers new packets as received, using the new circular buffer interface. It contributes a new algorithm which * supports both tail/head pointers and buffer wrap-around and * deals with overflow (head/tail move in lock-step). Signed-off-by: Gerrit Renker

dccp ccid-2: Algorithm to update buffer state

2010-11-15T06:11:59+00:00

This provides a routine to consistently update the buffer state when the peer acknowledges receipt of Ack Vectors; updating state in the list of Ack Vectors as well as in the circular buffer. While based on RFC 4340, several additional (and necessary) precautions were added to protect the consistency of the buffer state. These additions are essential, since analysis and experience showed that the basic algorithm was insufficient for this task (which lead to problems that were hard to debug). The algorithm now * deals with HC-sender acknowledging to HC-receiver and vice versa, * keeps track of the last unacknowledged but received seqno in tail_ackno, * has special cases to reset the overflow condition when appropriate, * is protected against receiving older information (would mess up buffer state). Signed-off-by: Gerrit Renker

dccp ccid-2: Implementation of circular Ack Vector buffer with overflow handling

2010-11-10T20:21:35+00:00

This completes the implementation of a circular buffer for Ack Vectors, by extending the current (linear array-based) implementation. The changes are: (a) An `overflow' flag to deal with the case of overflow. As before, dynamic growth of the buffer will not be supported; but code will be added to deal robustly with overflowing Ack Vector buffers. (b) A `tail_seqno' field. When naively implementing the algorithm of Appendix A in RFC 4340, problems arise whenever subsequent Ack Vector records overlap, which can bring the entire run length calculation completely out of synch. (This is documented on http://www.erg.abdn.ac.uk/users/gerrit/dccp/notes/\ ack_vectors/tracking_tail_ackno/ .) (c) The buffer length is now computed dynamically (i.e. current fill level), as the span between head to tail. As a result, dccp_ackvec_pending() is now simpler - the #ifdef is no longer necessary since buf_empty is always true when IP_DCCP_ACKVEC is not configured. Signed-off-by: Gerrit Renker

dccp ccid-2: Separate internals of Ack Vectors from option-parsing code

2010-11-10T20:21:02+00:00

This patch * separates Ack Vector housekeeping code from option-insertion code; * shifts option-specific code from ackvec.c into options.c; * introduces a dedicated routine to take care of the Ack Vector records; * simplifies the dccp_ackvec_insert_avr() routine: the BUG_ON was redundant, since the list is automatically arranged in descending order of ack_seqno. Signed-off-by: Gerrit Renker

dccp ccid-2: Ack Vector interface clean-up

2010-11-10T20:20:07+00:00

This patch brings the Ack Vector interface up to date. Its main purpose is to lay the basis for the subsequent patches of this set, which will use the new data structure fields and routines. There are no real algorithmic changes, rather an adaptation: (1) Replaced the static Ack Vector size (2) with a #define so that it can be adapted (with low loss / Ack Ratio, a value of 1 works, so 2 seems to be sufficient for the moment) and added a solution so that computing the ECN nonce will continue to work - even with larger Ack Vectors. (2) Replaced the #defines for Ack Vector states with a complete enum. (3) Replaced #defines to compute Ack Vector length and state with general purpose routines (inlines), and updated code to use these. (4) Added a `tail' field (conversion to circular buffer in subsequent patch). (5) Updated the (outdated) documentation for Ack Vector struct. (6) All sequence number containers now trimmed to 48 bits. (7) Removal of unused bits: * removed dccpav_ack_nonce from struct dccp_ackvec, since this is already redundantly stored in the `dccpavr_ack_nonce' (of Ack Vector record); * removed Elapsed Time for Ack Vectors (it was nowhere used); * replaced semantics of dccpavr_sent_len with dccpavr_ack_runlen, since the code needs to be able to remember the old run length; * reduced the de-/allocation routines (redundant / duplicate tests). Signed-off-by: Gerrit Renker