summaryrefslogtreecommitdiff
path: root/net/dccp/ackvec.c
AgeCommit message (Collapse)Author
2010-11-18dccp ccid-2: whitespace fix-upGerrit Renker
This fixes whitespace noise introduced in commit "dccp ccid-2: Algorithm to update buffer state", 5753fdfe8bd8e9a2ff9e5af19b0ffc78bfcd502a, 14 Nov 2010. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-15dccp ccid-2: Separate option parsing from CCID processingGerrit Renker
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 <gerrit@erg.abdn.ac.uk>
2010-11-15dccp ccid-2: Remove old infrastructureGerrit Renker
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 <gerrit@erg.abdn.ac.uk>
2010-11-15dccp ccid-2: Update code for the Ack Vector input/registration routineGerrit Renker
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 <gerrit@erg.abdn.ac.uk>
2010-11-15dccp ccid-2: Algorithm to update buffer stateGerrit Renker
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 <gerrit@erg.abdn.ac.uk>
2010-11-10dccp ccid-2: Implementation of circular Ack Vector buffer with overflow handlingGerrit Renker
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 <gerrit@erg.abdn.ac.uk>
2010-11-10dccp ccid-2: Separate internals of Ack Vectors from option-parsing codeGerrit Renker
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 <gerrit@erg.abdn.ac.uk>
2010-11-10dccp ccid-2: Ack Vector interface clean-upGerrit Renker
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 <gerrit@erg.abdn.ac.uk>
2010-07-18net: dccp: fix sign bugKulikov Vasiliy
'gap' is unsigned, so this code is wrong: gap = -new_head; ... if (gap > 0) { ... } Make 'gap' signed. The semantic patch that finds this problem (many false-positive results): (http://coccinelle.lip6.fr/) // <smpl> @ r1 @ identifier f; @@ int f(...) { ... } @@ identifier r1.f; type T; unsigned T x; @@ *x = f(...) ... *x > 0 Signed-off-by: Kulikov Vasiliy <segooon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-26dccp: remove unused function argumentGerrit Renker
This removes an unused 'sk' argument from several option-inserting functions. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-24dccp: Set per-connection CCIDs via socket optionsGerrit Renker
With this patch, TX/RX CCIDs can now be changed on a per-connection basis, which overrides the defaults set by the global sysctl variables for TX/RX CCIDs. To make full use of this facility, the remaining patches of this patch set are needed, which track dependencies and activate negotiated feature values. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-11dccp: Fix sparse warningsGerrit Renker
This patch fixes the following sparse warnings: * nested min(max()) expression: net/dccp/ccids/ccid3.c:91:21: warning: symbol '__x' shadows an earlier one net/dccp/ccids/ccid3.c:91:21: warning: symbol '__y' shadows an earlier one * Declaration of function prototypes in .c instead of .h file, resulting in "should it be static?" warnings. * Declared "struct dccpw" static (local to dccp_probe). * Disabled dccp_delayed_ack() - not fully removed due to RFC 4340, 11.3 ("Receivers SHOULD implement delayed acknowledgement timers ..."). * Used a different local variable name to avoid net/dccp/ackvec.c:293:13: warning: symbol 'state' shadows an earlier one net/dccp/ackvec.c:238:33: originally declared here * Removed unused functions `dccp_ackvector_print' and `dccp_ackvec_print'. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-01-28[ACKVEC]: Reduce length of identifiersGerrit Renker
This is reduces the length of the struct ackvec/ackvec_record fields. It is a purely text-based replacement: s#dccpavr_#avr_#g; s#dccpav_#av_#g; and increases readability somewhat. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: DIV_ROUND_UP cleanup (part two)Ilpo Järvinen
Hopefully captured all single statement cases under net/. I'm not too sure if there is some policy about #includes that are "guaranteed" (ie., in the current tree) to be available through some other #included header, so I just added linux/kernel.h to each changed file that didn't #include it previously. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[DCCP] ackvec: Convert to ktime_tArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-20mm: Remove slab destructors from kmem_cache_create().Paul Mundt
Slab destructors were no longer supported after Christoph's c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been BUGs for both slab and slub, and slob never supported them either. This rips out support for the dtor pointer from kmem_cache_create() completely and fixes up every single callsite in the kernel (there were about 224, not including the slab allocator definitions themselves, or the documentation references). Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-04-26[DCCP]: 48-bit sequence number arithmeticGerrit Renker
This patch * organizes the sequence arithmetic functions into one corner of dccp.h * performs a small modification of dccp_set_seqno to make it more widely reusable (now it is safe to use any number, since it performs modulo-2^48 assignment) * adds functions and generic macros for 48-bit sequence arithmetic: --48 bit complement --modulo-48 addition and modulo-48 subtraction --dccp_inc_seqno now a special case of add48 Constants renamed following a suggestion by Arnaldo. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-11[DCCP]: Whitespace cleanupsArnaldo Carvalho de Melo
That accumulated over the last months hackaton, shame on me for not using git-apply whitespace helping hand, will do that from now on. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-07[PATCH] slab: remove kmem_cache_tChristoph Lameter
Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-03[DCCP] ackvec: Split long ack vectors across multiple optionsAndrea Bittau
Ack vectors grow proportional to the window size. If an ack vector does not fit into a single option, it must be spread across multiple options. This patch will allow for windows to grow larger. Committer note: Simplified the patch a bit, original algorithm kept. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-03[DCCP] ackvec: infrastructure for sending more than one ackvec per packetAndrea Bittau
Commiter note: This was split from Andrea's original patch, in the process I changed the type of the ackvec index fields to u16 instead of to int and haven't folded dccp_ackvec_parse with dccp_ackvec_check_rcv_ackno. Next patch will actually do the insertion of more than one ackvec per packet, using, initially, up to a max of 2 ackvecs as per Andrea's original patch, then I'll work on support for larger ackvecs, be it using a sysctl or using setsockopt. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-03[DCCP] ackvec: Remove unused dccpav_ack_ptr field from dccp_ackvecAndrea Bittau
Commiter note: original patch was splitted. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-03[DCCP]: Simplified conditions due to use of enum:8 statesGerrit Renker
This reaps the benefit of the earlier patch, which changed the type of CCID 3 states to use enums, in that many conditions are now simplified and the number of possible (unexpected) values is greatly reduced. In a few instances, this also allowed to simplify pre-conditions; where care has been taken to retain logical equivalence. [DCCP]: Introduce a consistent BUG/WARN message scheme This refines the existing set of DCCP messages so that * BUG(), BUG_ON(), WARN_ON() have meaningful DCCP-specific counterparts * DCCP_CRIT (for severe warnings) is not rate-limited * DCCP_WARN() is introduced as rate-limited wrapper Using these allows a faster and cleaner transition to their original counterparts once the code has matured into a full DCCP implementation. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-03[DCCP]: enable debug messages also for static buildsGerrit Renker
This patch * makes debugging (when configured) work both for static / module build * provides generic debugging macros for use in other DCCP / CCID modules * adds missing information about debug parameters to Kconfig * performs some code tidy-up Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-03[DCCP] ACKVEC: Optimization - Do not traverse records if none will be foundAndrea Bittau
Do not traverse the list of ack vector records [proportional to window size] when we know we will not find what we are looking for. This is especially useful because ack vectors are checked twice: 1) Upon parsing of options. 2) Upon notification of a new ack. All of the work will occur during check #1. Therefore, when check #2 is performed, no new work will be done. This is now "detected" and there is no performance hit when doing #2. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-03[DCCP]: Miscellaneous code tidy-upsGerrit Renker
This patch does not change code; it performs some trivial clean/tidy-ups: * removal of a `debug_prefix' string in favour of the already existing dccp_role(sk) * add documentation of structures and constants * separated out the cases for invalid packets (step 1 of the packet validation) * removing duplicate statements * combining declaration & initialisation Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-10-24[DCCP]: Update documentation references.Gerrit Renker
Updates the references to spec documents throughout the code, taking into account that * the DCCP, CCID 2, and CCID 3 drafts all became RFCs in March this year * RFC 1063 was obsoleted by RFC 1191 * draft-ietf-tcpimpl-pmtud-0x.txt was published as an Informational RFC, RFC 2923 on 2000-09-22. All references verified. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[DCCP] ackvec: Remove unused variablesAndrea Bittau
Get rid of unused variables in ackvector state. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[DCCP] ackvec: Fix how DCCP_ACKVEC_STATE_NOT_RECEIVED is usedAndrea Bittau
Fix the way state is masked out. DCCP_ACKVEC_STATE_NOT_RECEIVED is defined as appears in the packet, therefore bit shifting is not required. This fix allows CCID2 to correctly detect losses. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[DCCP] ACKVEC: fix ackvector length calculationAndrea Bittau
Fix ackvector length calculation upon receiving an "ack-of-ack". This patch avoids the ackvector from growing too large which causes it to not be inserted into packets. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-12[DCCP] Ackvec: fix soft lockup in ackvec handling codeAndrea Bittau
A soft lockup existed in the handling of ack vector records. Specifically, when a tail of the list of ack vector records was removed, it was possible to end up iterating infinitely on an element of the tail. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-21[DCCP] options: Make dccp_insert_options & friends yell on errorArnaldo Carvalho de Melo
And not the silly LIMIT_NETDEBUG and silently return without inserting the option requested. Also drop some old debugging messages associated to option insertion. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-21[DCCP] ackvec: Delete all the ack vector records in dccp_ackvec_freeArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-21[DCCP] ackvec: Introduce ack vector recordsAndrea Bittau
Based on a patch by Andrea Bittau. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-21[DCCP] ackvec: Introduce dccp_ackvec_slabArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-21[DCCP] ackvec: Ditch dccpav_buf_lenArnaldo Carvalho de Melo
Simplifying the code a bit as we're always using DCCP_MAX_ACKVEC_LEN. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-17[NET]: "signed long" -> "long"Kris Katterjohn
Signed-off-by: Kris Katterjohn <kjak@users.sourceforge.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-04[DCCP] ackvec: use u8 for the buf offsetsArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-01-04[DCCP] ackvec: Fix spelling of "throw"Andrea Bittau
Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-10-08[PATCH] gfp flags annotations - part 1Al Viro
- added typedef unsigned int __nocast gfp_t; - replaced __nocast uses for gfp flags with gfp_t - it gives exactly the same warnings as far as sparse is concerned, doesn't change generated code (from gcc point of view we replaced unsigned int with typedef) and documents what's going on far better. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-18[DCCP]: Move the ack vector code to net/dccp/ackvec.[ch]Arnaldo Carvalho de Melo
Isolating it, that will be used when we introduce a CCID2 (TCP-Like) implementation. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>