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2009-01-26Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
2009-01-26networking: document "nc" in addition to "netcat" in netconsole.txtJesse Barnes
It always annoyed me that the netconsole documentation didn't give me the correct command for my distro. Update it with a command line that actually works on my Fedora install. Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21dccp: Implement both feature-local and feature-remote Sequence Window featureGerrit Renker
This adds full support for local/remote Sequence Window feature, from which the * sequence-number-validity (W) and * acknowledgment-number-validity (W') windows derive as specified in RFC 4340, 7.5.3. Specifically, the following is contained in this patch: * integrated new socket fields into dccp_sk; * updated the update_gsr/gss routines with regard to these fields; * updated handler code: the Sequence Window feature is located at the TX side, so the local feature is meant if the handler-rx flag is false; * the initialisation of `rcv_wnd' in reqsk is removed, since - rcv_wnd is not used by the code anywhere; - sequence number checks are not done in the LISTEN state (cf. 7.5.3); - dccp_check_req checks the Ack number validity more rigorously; * the `struct dccp_minisock' became empty and is now removed. 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>
2009-01-06trivial: fix an -> a typos in documentation and commentsFrederik Schwarzer
It is always "an" if there is a vowel _spoken_ (not written). So it is: "an hour" (spoken vowel) but "a uniform" (spoken 'j') Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-06trivial: fix then -> than typos in comments and documentationFrederik Schwarzer
- (better, more, bigger ...) then -> (...) than Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-12-08dccp ccid-2: Phase out the use of boolean Ack Vector sysctlGerrit Renker
This removes the use of the sysctl and the minisock variable for the Send Ack Vector feature, as it now is handled fully dynamically via feature negotiation (i.e. when CCID-2 is enabled, Ack Vectors are automatically enabled as per RFC 4341, 4.). Using a sysctl in parallel to this implementation would open the door to crashes, since much of the code relies on tests of the boolean minisock / sysctl variable. Thus, this patch replaces all tests of type if (dccp_msk(sk)->dccpms_send_ack_vector) /* ... */ with if (dp->dccps_hc_rx_ackvec != NULL) /* ... */ The dccps_hc_rx_ackvec is allocated by the dccp_hdlr_ackvec() when feature negotiation concluded that Ack Vectors are to be used on the half-connection. Otherwise, it is NULL (due to dccp_init_sock/dccp_create_openreq_child), so that the test is a valid one. The activation handler for Ack Vectors is called as soon as the feature negotiation has concluded at the * server when the Ack marking the transition RESPOND => OPEN arrives; * client after it has sent its ACK, marking the transition REQUEST => PARTOPEN. Adding the sequence number of the Response packet to the Ack Vector has been removed, since (a) connection establishment implies that the Response has been received; (b) the CCIDs only look at packets received in the (PART)OPEN state, i.e. this entry will always be ignored; (c) it can not be used for anything useful - to detect loss for instance, only packets received after the loss can serve as pseudo-dupacks. There was a FIXME to change the error code when dccp_ackvec_add() fails. I removed this after finding out that: * the check whether ackno < ISN is already made earlier, * this Response is likely the 1st packet with an Ackno that the client gets, * so when dccp_ackvec_add() fails, the reason is likely not a packet error. 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>
2008-12-08dccp: Remove manual influence on NDP Count featureGerrit Renker
Updating the NDP count feature is handled automatically now: * for CCID-2 it is disabled, since the code does not use NDP counts; * for CCID-3 it is enabled, as NDP counts are used to determine loss lengths. Allowing the user to change NDP values leads to unpredictable and failing behaviour, since it is then possible to disable NDP counts even when they are needed (e.g. in CCID-3). This means that only those user settings are sensible that agree with the values for Send NDP Count implied by the choice of CCID. But those settings are already activated by the feature negotiation (CCID dependency tracking), hence this form of support is redundant. At startup the initialisation of the NDP count feature uses the default value of 0, which is done implicitly by the zeroing-out of the socket when it is allocated. If the choice of CCID or feature negotiation enables NDP count, this will then be updated via the NDP activation handler. 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>
2008-12-08dccp: Remove obsolete parts of the old CCID interfaceGerrit Renker
The TX/RX CCIDs of the minisock are now redundant: similar to the Ack Vector case, their value equals initially that of the sysctl, but at the end of feature negotiation may be something different. The old interface removed by this patch thus has been replaced by the newer interface to dynamically query the currently loaded CCIDs. Also removed are the constructors for the TX CCID and the RX CCID, since the switch "rx <-> non-rx" is done by the handler in minisocks.c (and the handler is the only place in the code where CCIDs are loaded). 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>
2008-12-08netdevice: Kill netdev->privWang Chen
This is the last shoot of this series. After I removing all directly reference of netdev->priv, I am killing "priv" of "struct net_device" and fixing relative comments/docs. Anyone will not be allowed to reference netdev->priv directly. If you want to reference the memory of private data, use netdev_priv() instead. If the private data is not allocted when alloc_netdev(), use netdev->ml_priv to point that memory after you creating that private data. Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-23dccp: 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>
2008-11-22WAN: new synchronous PPP implementation for generic HDLC.Krzysztof Hałasa
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2008-11-21mac80211_hwsim: Update documentation (AP mode enabled)Jouni Malinen
AP mode is now enabled in mac80211, so there is no need to point users to an additional patch to enable the mode. In addition, add a pointer to more hwsim test cases in hostap.git. Signed-off-by: Jouni Malinen <j@w1.fi> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-11-20Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/ixgbe/ixgbe_main.c include/net/mac80211.h net/phonet/af_phonet.c
2008-11-19phylib: fix phy name example in documentationPaulius Zaleckas
All MDIO bus drivers currently name bus with "%x" format. There is one exception where mv643xx_eth driver is using "%d". Phy address on the bus uses format "%02x". Fixing phy name example to match all real life MDIO drivers. Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16dccp: Deprecate Ack Ratio sysctlGerrit Renker
This patch deprecates the Ack Ratio sysctl, since * Ack Ratio is entirely ignored by CCID-3 and CCID-4, * Ack Ratio currently doesn't work in CCID-2 (i.e. is always set to 1); * even if it would work in CCID-2, there is no point for a user to change it: - Ack Ratio is constrained by cwnd (RFC 4341, 6.1.2), - if Ack Ratio > cwnd, the system resorts to spurious RTO timeouts (since waiting for Acks which will never arrive in this window), - cwnd is not a user-configurable value. The only reasonable place for Ack Ratio is to print it for debugging. It is planned to do this later on, as part of e.g. dccp_probe. With this patch Ack Ratio is now under full control of feature negotiation: * Ack Ratio is resolved as a dependency of the selected CCID; * if the chosen CCID supports it (i.e. CCID == CCID-2), Ack Ratio is set to the default of 2, following RFC 4340, 11.3 - "New connections start with Ack Ratio 2 for both endpoints"; * what happens then is part of another patch set, since it concerns the dynamic update of Ack Ratio while the connection is in full flight. Thanks to Tomasz Grobelny for discussion leading up to this patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-12dccp: Query supported CCIDsGerrit Renker
This provides a data structure to record which CCIDs are locally supported and three accessor functions: - a test function for internal use which is used to validate CCID requests made by the user; - a copy function so that the list can be used for feature-negotiation; - documented getsockopt() support so that the user can query capabilities. The data structure is a table which is filled in at compile-time with the list of available CCIDs (which in turn depends on the Kconfig choices). Using the copy function for cloning the list of supported CCIDs is useful for feature negotiation, since the negotiation is now with the full list of available CCIDs (e.g. {2, 3}) instead of the default value {2}. This means negotiation will not fail if the peer requests to use CCID3 instead of CCID2. 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>
2008-11-06bonding: alternate agg selection policies for 802.3adJay Vosburgh
This patch implements alternative aggregator selection policies for 802.3ad. The existing policy, now termed "stable," selects the active aggregator by greatest bandwidth, and only reselects a new aggregator if the active aggregator is entirely disabled (no more ports or all ports down). This patch adds two new policies: bandwidth and count, selecting the active aggregator by total bandwidth (like the stable policy) or by the number of ports in the aggregator, respectively. These two policies also differ from the stable policy in that they will reselect the active aggregator when availability-related changes occur in the bond (e.g., link state change). This permits "gang failover" within 802.3ad, allowing redundant aggregators along parallel paths to always maintain the "best" aggregator as the active aggregator (rather than having to wait for the active to entirely fail). This patch also updates the driver version to 3.5.0. Signed-off-by: Jay Vosburgh <fubar@us.ibm.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-11-06bonding: send IPv6 neighbor advertisement on failoverBrian Haley
This patch adds better IPv6 failover support for bonding devices, especially when in active-backup mode and there are only IPv6 addresses configured, as reported by Alex Sidorenko. - Creates a new file, net/drivers/bonding/bond_ipv6.c, for the IPv6-specific routines. Both regular bonds and VLANs over bonds are supported. - Adds a new tunable, num_unsol_na, to limit the number of unsolicited IPv6 Neighbor Advertisements that are sent on a failover event. Default is 1. - Creates two new IPv6 neighbor discovery functions: ndisc_build_skb() ndisc_send_skb() These were required to support VLANs since we have to be able to add the VLAN id to the skb since ndisc_send_na() and friends shouldn't be asked to do this. These two routines are basically __ndisc_send() split into two pieces, in a slightly different order. - Updates Documentation/networking/bonding.txt and bumps the rev of bond support to 3.4.0. On failover, this new code will generate one packet: - An unsolicited IPv6 Neighbor Advertisement, which helps the switch learn that the address has moved to the new slave. Testing has shown that sending just the NA results in pretty good behavior when in active-back mode, I saw no lost ping packets for example. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: Jay Vosburgh <fubar@us.ibm.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-11-02bonding: update docs to correctly reflect arp_ip_target behaviorAndy Gospodarek
This documentation patch hopes to clarify that the '+' was only needed for Fedora 7 and Red Hat Enterprise Linux 5.0 and 5.1. After that the IP addreses could be added as a comma separated list just like the module option. Signed-off-by: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-10-31wireless: remove struct regdom hintingJohannes Berg
The code needs to be split out and cleaned up, so as a first step remove the capability, to add it back in a subsequent patch as a separate function. Also remove the publically facing return value of the function and the wiphy argument. A number of internal functions go from being generic helpers to just being used for alpha2 setting. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-10-31wireless: make regdom passing semantics simplerJohannes Berg
The regdom struct is given to the core, so it might as well free it in error conditions. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-10-31ipw2x00: change default policy for auto-associateTim Gardner
Do not attempt association until directed to do so by a user space application. In particular, this avoids race conditions with NetworkManager association state. Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Acked-by: Dan Williams <dcbw@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-10-31Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/p54/p54common.c
2008-10-30Rationalise Randy's address a bitAlan Cox
Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-30.gitignore updatesAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-27net: implement emergency route cache rebulds when gc_elasticity is exceededNeil Horman
This is a patch to provide on demand route cache rebuilding. Currently, our route cache is rebulid periodically regardless of need. This introduced unneeded periodic latency. This patch offers a better approach. Using code provided by Eric Dumazet, we compute the standard deviation of the average hash bucket chain length while running rt_check_expire. Should any given chain length grow to larger that average plus 4 standard deviations, we trigger an emergency hash table rebuild for that net namespace. This allows for the common case in which chains are well behaved and do not grow unevenly to not incur any latency at all, while those systems (which may be being maliciously attacked), only rebuild when the attack is detected. This patch take 2 other factors into account: 1) chains with multiple entries that differ by attributes that do not affect the hash value are only counted once, so as not to unduly bias system to rebuilding if features like QOS are heavily used 2) if rebuilding crosses a certain threshold (which is adjustable via the added sysctl in this patch), route caching is disabled entirely for that net namespace, since constant rebuilding is less efficient that no caching at all Tested successfully by me. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (26 commits) decnet: Fix compiler warning in dn_dev.c IPV6: Fix default gateway criteria wrt. HIGH/LOW preference radv option net/802/fc.c: Fix compilation warnings netns: correct mib stats in ip6_route_me_harder() netns: fix net_generic array leak rt2x00: fix regression introduced by "mac80211: free up 2 bytes in skb->cb" rtl8187: Add USB ID for Belkin F5D7050 with RTL8187B chip p54usb: Device ID updates mac80211: fixme for kernel-doc ath9k/mac80211: disallow fragmentation in ath9k, report to userspace libertas : Remove unused variable warning for "old_channel" from cmd.c mac80211: Fix scan RX processing oops orinoco: fix unsafe locking in spectrum_cs_suspend orinoco: fix unsafe locking in orinoco_cs_resume cfg80211: fix debugfs error handling mac80211: fix debugfs netdev rename iwlwifi: fix ct kill configuration for 5350 mac80211: fix HT information element parsing p54: Fix compilation problem on PPC mac80211: fix debugfs lockup ...
2008-10-16Remove Andrew Morton's http://www.zip.com.au/~akpm/FD Cami
Remove Andrew Morton's http://www.zip.com.au/~akpm/ urls, update to new ones when necessary, delete references otherwise. There are still instances of that living in: Documentation/zh_CN/HOWTO Documentation/zh_CN/SubmittingPatches Documentation/ko_KR/HOWTO Documentation/ja_JP/SubmittingPatches Signed-off-by: Francois Cami <francois.cami@free.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16Remove Andrew Morton's old email accountsFrancois Cami
People can use the real name an an index into MAINTAINERS to find the current email address. Signed-off-by: Francois Cami <francois.cami@free.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-14Phonet: Simple doc fix.Randy Macleod
From: "Randy Macleod" <macleodr@nortel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-08netfilter: Add documentation for tproxyKOVACS Krisztian
Add basic usage instructions to Documentation/networking. Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu> Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-05Phonet: pipe end-point protocol documentationRémi Denis-Courmont
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-30Phonet: improve documentationRémi Denis-Courmont
Fix grammar errors spotted by Randy Dunlap, and adds some more details. Signed-off-by: Remi Denis-Courmont <remi.denis-courmont@nokia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-23can: Add documentation for virtual CAN driver usageOliver Hartkopp
This patch adds a usage documentation for the virtual CAN driver (vcan). Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-22Phonet: kernel documentationRemi Denis-Courmont
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-19Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6
2008-09-18qlge: New Qlogic 10Gb Ethernet Driver.Ron Mercer
Signed-off-by: Ron Mercer <ron.mercer@qlogic.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-09-15cfg80211: Add new wireless regulatory infrastructureLuis R. Rodriguez
This adds the new wireless regulatory infrastructure. The main motiviation behind this was to centralize regulatory code as each driver was implementing their own regulatory solution, and to replace the initial centralized code we have where: * only 3 regulatory domains are supported: US, JP and EU * regulatory domains can only be changed through module parameter * all rules were built statically in the kernel We now have support for regulatory domains for many countries and regulatory domains are now queried through a userspace agent through udev allowing distributions to update regulatory rules without updating the kernel. Each driver can regulatory_hint() a regulatory domain based on either their EEPROM mapped regulatory domain value to a respective ISO/IEC 3166-1 country code or pass an internally built regulatory domain. We also add support to let the user set the regulatory domain through userspace in case of faulty EEPROMs to further help compliance. Support for world roaming will be added soon for cards capable of this. For more information see: http://wireless.kernel.org/en/developers/Regulatory/CRDA For now we leave an option to enable the old module parameter, ieee80211_regdom, and to build the 3 old regdomains statically (US, JP and EU). This option is CONFIG_WIRELESS_OLD_REGULATORY. These old static definitions and the module parameter is being scheduled for removal for 2.6.29. Note that if you use this you won't make use of a world regulatory domain as its pointless. If you leave this option enabled and if CRDA is present and you use US or JP we will try to ask CRDA to update us a regulatory domain for us. Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-09-12multiq: Further multiqueue cleanupAlexander Duyck
This patch resolves a few issues found with multiq including wording suggestions and a problem seen in the allocation of queues. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-12skbedit: Fix a typo in the documentationAlexander Duyck
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-12pkt_action: add new action skbeditAlexander Duyck
This new action will have the ability to change the priority and/or queue_mapping fields on an sk_buff. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-12pkt_sched: Add multiqueue scheduler supportAlexander Duyck
This patch is intended to add a qdisc to support the new tx multiqueue architecture by providing a band for each hardware queue. By doing this it is possible to support a different qdisc per physical hardware queue. This qdisc uses the skb->queue_mapping to select which band to place the traffic onto. It then uses a round robin w/ a check to see if the subqueue is stopped to determine which band to dequeue the packet from. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-09This reverts "Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/dccp_exp"Gerrit Renker
as it accentally contained the wrong set of patches. These will be submitted separately. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Policy-based packet dequeueing infrastructureTomasz Grobelny
This patch adds a generic infrastructure for policy-based dequeueing of TX packets and provides two policies: * a simple FIFO policy (which is the default) and * a priority based policy (set via socket options). Both policies honour the tx_qlen sysctl for the maximum size of the write queue (can be overridden via socket options). The priority policy uses skb->priority internally to assign an u32 priority identifier, using the same ranking as SO_PRIORITY. The skb->priority field is set to 0 when the packet leaves DCCP. The priority is supplied as ancillary data using cmsg(3), the patch also provides the requisite parsing routines. Signed-off-by: Tomasz Grobelny <tomasz@grobelny.oswiecenia.net> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Implement both feature-local and feature-remote Sequence Window featureGerrit Renker
This adds full support for local/remote Sequence Window feature, from which the * sequence-number-validity (W) and * acknowledgment-number-validity (W') windows derive as specified in RFC 4340, 7.5.3. Specifically, the following changes are introduced: * integrated new socket fields into dccp_sk; * updated the update_gsr/gss routines with regard to these fields; * updated handler code: the Sequence Window feature is located at the TX side, so the local feature is meant if the handler-rx flag is false; * the initialisation of `rcv_wnd' in reqsk is removed, since - rcv_wnd is not used by the code anywhere; - sequence number checks are not done in the LISTEN state (cf. 7.5.3); - dccp_check_req checks the Ack number validity more rigorously; * the `struct dccp_minisock' became empty and is now removed. Until the handshake completes with activating negotiated values, the local/remote Sequence-Window values are undefined and thus can not reliably be estimated. This issue is addressed in a separate patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp ccid-2: Phase out the use of boolean Ack Vector sysctlGerrit Renker
This removes the use of the sysctl and the minisock variable for the Send Ack Vector feature, which is now handled fully dynamically via feature negotiation; i.e. when CCID2 is enabled, Ack Vectors are automatically enabled (as per RFC 4341, 4.). Using a sysctl in parallel to this implementation would open the door to crashes, since much of the code relies on tests of the boolean minisock / sysctl variable. Thus, this patch replaces all tests of type if (dccp_msk(sk)->dccpms_send_ack_vector) /* ... */ with if (dp->dccps_hc_rx_ackvec != NULL) /* ... */ The dccps_hc_rx_ackvec is allocated by the dccp_hdlr_ackvec() when feature negotiation concluded that Ack Vectors are to be used on the half-connection. Otherwise, it is NULL (due to dccp_init_sock/dccp_create_openreq_child), so that the test is a valid one. The activation handler for Ack Vectors is called as soon as the feature negotiation has concluded at the * server when the Ack marking the transition RESPOND => OPEN arrives; * client after it has sent its ACK, marking the transition REQUEST => PARTOPEN. Adding the sequence number of the Response packet to the Ack Vector has been removed, since (a) connection establishment implies that the Response has been received; (b) the CCIDs only look at packets received in the (PART)OPEN state, i.e. this entry will always be ignored; (c) it can not be used for anything useful - to detect loss for instance, only packets received after the loss can serve as pseudo-dupacks. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Remove manual influence on NDP Count featureGerrit Renker
Updating the NDP count feature is handled automatically now: * for CCID-2 it is disabled, since the code does not use NDP counts; * for CCID-3 it is enabled, as NDP counts are used to determine loss lengths. Allowing the user to change NDP values leads to unpredictable and failing behaviour, since it is then possible to disable NDP counts even when they are needed (e.g. in CCID-3). This means that only those user settings are sensible that agree with the values for Send NDP Count implied by the choice of CCID. But those settings are already activated by the feature negotiation (CCID dependency tracking), hence this form of support is redundant. At startup the initialisation of the NDP count feature is with the default value of 0, which is done implicitly by the zeroing-out of the socket when it is allocated. If the choice of CCID or feature negotiation enables NDP count, this will then be updated via the NDP activation handler. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Remove obsolete parts of the old CCID interfaceGerrit Renker
The TX/RX CCIDs of the minisock are now redundant: similar to the Ack Vector case, their value equals initially that of the sysctl, but at the end of feature negotiation may be something different. The old interface removed by this patch thus has been replaced by the newer interface to dynamically query the currently loaded CCIDs earlier in this patch set. Also removed the constructors for the TX CCID and the RX CCID, since the switch rx/non-rx is done by the handler in minisocks.c (and the handler is the only place in the code where CCIDs are loaded). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: 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. Note on the maximum number of CCIDs that can be registered: ----------------------------------------------------------- The maximum number of CCIDs that can be registered on the socket is constrained by the space in a Confirm/Change feature negotiation option. The space in these in turn depends on the size of header options as defined in RFC 4340, 5.8. Since this is a recurring constant, it has been moved from ackvec.h into linux/dccp.h, clarifying its purpose. Relative to this size, the maximum number of CCID identifiers that can be present in a Confirm option (which always consumes 1 byte more than a Change option, cf. 6.1) is 2 bytes less than the maximum TLV size: one for the CCID-feature-type and one for the selected value. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Deprecate Ack Ratio sysctlGerrit Renker
This patch deprecates the Ack Ratio sysctl, since * Ack Ratio is entirely ignored by CCID-3 and CCID-4, * Ack Ratio currently doesn't work in CCID-2 (i.e. is always set to 1); * even if it would work in CCID-2, there is no point for a user to change it: - Ack Ratio is constrained by cwnd (RFC 4341, 6.1.2), - if Ack Ratio > cwnd, the system resorts to spurious RTO timeouts (since waiting for Acks which will never arrive in this window), - cwnd is not a user-configurable value. The only reasonable place for Ack Ratio is to print it for debugging. It is planned to do this later on, as part of e.g. dccp_probe. With this patch Ack Ratio is now under full control of feature negotiation: * Ack Ratio is resolved as a dependency of the selected CCID; * if the chosen CCID supports it (i.e. CCID == CCID-2), Ack Ratio is set to the default of 2, following RFC 4340, 11.3 - "New connections start with Ack Ratio 2 for both endpoints"; * what happens then is part of another patch set, since it concerns the dynamic update of Ack Ratio while the connection is in full flight. Thanks to Tomasz Grobelny for discussion leading up to this patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>