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2009-10-02net: Fix wrong sizeofJean Delvare1-1/+1
Which is why I have always preferred sizeof(struct foo) over sizeof(var). Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-21trivial: fix typo "to to" in multiple filesAnand Gadiyar1-1/+1
Signed-off-by: Anand Gadiyar <gadiyar@ti.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-05sctp: Sysctl configuration for IPv4 Address ScopingBhaskar Dutta1-0/+10
This patch introduces a new sysctl option to make IPv4 Address Scoping configurable <draft-stewart-tsvwg-sctp-ipv4-00.txt>. In networking environments where DNAT rules in iptables prerouting chains convert destination IP's to link-local/private IP addresses, SCTP connections fail to establish as the INIT chunk is dropped by the kernel due to address scope match failure. For example to support overlapping IP addresses (same IP address with different vlan id) a Layer-5 application listens on link local IP's, and there is a DNAT rule that maps the destination IP to a link local IP. Such applications never get the SCTP INIT if the address-scoping draft is strictly followed. This sysctl configuration allows SCTP to function in such unconventional networking environments. Sysctl options: 0 - Disable IPv4 address scoping draft altogether 1 - Enable IPv4 address scoping (default, current behavior) 2 - Enable address scoping but allow IPv4 private addresses in init/init-ack 3 - Enable address scoping but allow IPv4 link local address in init/init-ack Signed-off-by: Bhaskar Dutta <bhaskar.dutta@globallogic.com> Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2009-09-02RTO connection timeout: sysctl documentation updateDamian Lukowski1-11/+26
This patch updates the sysctl documentation concerning the interpretation of tcp_retries{1,2} and tcp_orphan_retries. Signed-off-by: Damian Lukowski <damian@tvk.rwth-aachen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-19ieee802154: document the skb->cb usage clearly.Dmitry Eremin-Solenikov1-2/+7
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
2009-08-13documentation: fix wrt. headers renameDmitry Baryshkov1-5/+4
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-27Merge branch 'for-linus' of ↵David S. Miller2-1/+3
git://git.kernel.org/pub/scm/linux/kernel/git/lowpan/lowpan
2009-07-27trivial: fix typo in ieee802154 documentation and add it to indexThadeu Lima de Souza Cascardo2-1/+3
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
2009-07-17Update Andreas Koensgen's email addressRalf Baechle1-1/+1
The kernel has used a stale email address of Andreas for a few years. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-15Merge branch 'master' of ↵David S. Miller7-9/+9
master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/scsi/fcoe/fcoe.c net/core/drop_monitor.c net/core/net-traces.c
2009-06-12trivial: Miscellaneous documentation typo fixesMatt LaPlante7-9/+9
Fix various typos in documentation txts. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-06-12[PATCH] net core: Some interface flags not returned by SIOCGIFFLAGSJohn Dykstra1-3/+0
Commit b00055aacdb172c05067612278ba27265fcd05ce " [NET] core: add RFC2863 operstate" defined new interface flag values. Its documentation specified that these flags could be accessed from user space via SIOCGIFFLAGS. However, this does not work because the new flags do not fit in that ioctl's argument width. Change the documentation to match the code's behavior. Also change the source to explicitly show the truncation. This _should_ have no effect on executable code, and did not with gcc 4.2.4 generating x86 code. A new ioctl could be defined to return all interface flags to user space. However, since this has been broken for three years with no one complaining, there doesn't seem much need. They are still accessible via netlink. Reported-by: "Fredrik Arnerup" <fredrik.arnerup@edgeware.tv> Signed-off-by: John Dykstra <john.dykstra1@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-09ieee802154: add documentation about our stackSergey Lapin1-0/+76
Add MAINTAINERS entry and a small text describing our stack interfaces, how to hook the drivers, etc. Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Signed-off-by: Sergey Lapin <slapin@ossfans.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-01IPv6: Add 'autoconf' and 'disable_ipv6' module parametersBrian Haley2-0/+44
Add 'autoconf' and 'disable_ipv6' parameters to the IPv6 module. The first controls if IPv6 addresses are autoconfigured from prefixes received in Router Advertisements. The IPv6 loopback (::1) and link-local addresses are still configured. The second controls if IPv6 addresses are desired at all. No IPv6 addresses will be added to any interfaces. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-19net: TX_RING and packet mmapJohann Baudy1-19/+121
New packet socket feature that makes packet socket more efficient for transmission. - It reduces number of system call through a PACKET_TX_RING mechanism, based on PACKET_RX_RING (Circular buffer allocated in kernel space which is mmapped from user space). - It minimizes CPU copy using fragmented SKB (almost zero copy). Signed-off-by: Johann Baudy <johann.baudy@gnu-log.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-19Merge branch 'master' of ↵David S. Miller1-3/+12
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/scsi/fcoe/fcoe.c
2009-05-19can: Documentation for the CAN device driver interfaceWolfgang Grandegger1-38/+197
This patch documents the CAN netowrk device drivers interface, removes obsolete documentation and adds some useful links to CAN resources. Signed-off-by: Wolfgang Grandegger <wg@grandegger.com> Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-18Doc: fixed descriptions on /proc/sys/net/core/* and /proc/sys/net/unix/*Wang Tinggong1-3/+12
Signed-off-by: Wang Tinggong <wangtinggong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-04tcp: extend ECN sysctl to allow server-side only ECNIlpo Järvinen1-1/+10
This should be very safe compared with full enabled, so I see no reason why it shouldn't be done right away. As ECN can only be negotiated if the SYN sending party is also supporting it, somebody in the loop probably knows what he/she is doing. If SYN does not ask for ECN, the server side SYN-ACK is identical to what it is without ECN. Thus it's quite safe. The chosen value is safe w.r.t to existing configs which choose to currently set manually either 0 or 1 but silently upgrades those who have not explicitly requested ECN off. Whether to just enable both sides comes up time to time but unless that gets done now we can at least make the servers aware of ECN already. As there are some known problems to occur if ECN is enabled, it's currently questionable whether there's any real gain from enabling clients as servers mostly won't support it anyway (so we'd hit just the negative sides). After enabling the servers and getting that deployed, the client end enable really has some potential gain too. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-23mac80211: update injection documentationJohannes Berg1-22/+6
We don't currently support antenna or rate setting, so remove that. Also update the link -- the current one is dead and the wiki can be kept updated easier. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-13Bonding: fix zero address hole bug in arp_ip_target listBrian Haley1-1/+1
Fix a zero address hole bug in the bonding arp_ip_target list that was causing the bond to ignore ARP replies (bugz 13006). Instead of just setting the array entry to zero, we now copy any additional entries down one slot, putting the zero entry at the end. With this change we can now have all the loops that walk the array stop when they hit a zero since there will be no addresses after it. Changes are based in part on code fragment provided in kernel: bugzilla 13006: http://bugzilla.kernel.org/show_bug.cgi?id=13006 by Steve Howard <steve@astutenetworks.com> Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: Jay Vosburgh <fubar@us.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-02Neterion: Driver help fileRamkrishna Vepa1-0/+100
- vxge driver help text file. - No change from previous submission. - Changes in previous submissions - Removed the performance tuning section with instructions to disable time stamps and change sysctl settings - Reported by Dave Miller General clean up. - Removed tx/rx_pause, exec_mode, tx_steering_type, rx_steering_type, gro, intr_type, rx & tx max_indicate_pkts and exec_mode loadable parameters. The driver default settings work well in most if not all cases. Another patch to configure these parameters with ethtool will be released in the future - Reported by Stephen Hemminger. - Incorporated following fixes based on comments from Ben Hutchings Removed references to earlier kernel versions. Removed sections that are similar for all drivers - Load/Unload Identifying the adapter/interface Boot time configuration Removed loadable parameter - NAPI - Napi is always enabled. rx_steering_type & ring_blocks - The driver default settings work well in most if not all cases. Another patch to configure these parameters with ethtool will be released in the future. Removed ethtool support section - No need to duplicate ethtool docs here. Removed Known Issue on SUSE 9 - Doesn't apply when using a current kernel. Removed Common Problems section - These don't apply to in-tree modules. Removed Available Downloads section - Not sure this belongs in-tree. Removed Copyright information - This notice doesn't belong in the kernel. Signed-off-by: Sivakumar Subramani <sivakumar.subramani@neterion.com> Signed-off-by: Rastapur Santosh <santosh.rastapur@neterion.com> Signed-off-by: Ramkrishna Vepa <ram.vepa@neterion.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-19ipv6: Fix incorrect disable_ipv6 behaviorBrian Haley1-1/+3
Fix the behavior of allowing both sysctl and addrconf_dad_failure() to set the disable_ipv6 parameter without any bad side-effects. If DAD fails and accept_dad > 1, we will still set disable_ipv6=1, but then instead of allowing an RA to add an address then immediately fail DAD, we simply don't allow the address to be added in the first place. This also lets the user set this flag and disable all IPv6 addresses on the interface, or on the entire system. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-14ixgbe: Add documentation for the driverPJ Waskiewicz1-0/+199
Documentation for the ixgbe driver in the kernel docs area is missing. This adds that documentation. Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-05Merge branch 'master' of ↵David S. Miller1-0/+35
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/tokenring/tmspci.c drivers/net/ucc_geth_mii.c
2009-03-04IPv6: add "disable" module parameter support to ipv6.koBrian Haley1-0/+35
Add "disable" module parameter support to ipv6.ko by specifying "disable=1" on module load. We just do the minimum of initializing inetsw6[] so calls from other modules to inet6_register_protosw() won't OOPs, then bail out. No IPv6 addresses or sockets can be created as a result, and a reboot is required to enable IPv6. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-27RDS: DocumentationAndy Grover1-0/+356
This file documents the specifics of the RDS sockets API, as well as covering some of the details of its internal implementation. Signed-off-by: Andy Grover <andy.grover@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-24Doc: Cleanup whitespaces in ip-sysctl.txtJesper Dangaard Brouer1-59/+59
Fix up whitespaces while going though ip-sysctl.txt anyway. Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-24Doc: Fix typos in ip-sysctl.txt about rp_filter.Jesper Dangaard Brouer1-2/+2
First fix a typo in Stephens patch ;-) Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-23ip: add loose reverse path filteringStephen Hemminger1-9/+15
Extend existing reverse path filter option to allow strict or loose filtering. (See http://en.wikipedia.org/wiki/Reverse_path_filtering). For compatibility with existing usage, the value 1 is chosen for strict mode and 2 for loose mode. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-16ip: support for TX timestamps on UDP and RAW socketsPatrick Ohly1-0/+2
Instructions for time stamping outgoing packets are take from the socket layer and later copied into the new skb. Signed-off-by: Patrick Ohly <patrick.ohly@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-16net: new user space API for time stamping of incoming and outgoing packetsPatrick Ohly4-0/+718
User space can request hardware and/or software time stamping. Reporting of the result(s) via a new control message is enabled separately for each field in the message because some of the fields may require additional computation and thus cause overhead. User space can tell the different kinds of time stamps apart and choose what suits its needs. When a TX timestamp operation is requested, the TX skb will be cloned and the clone will be time stamped (in hardware or software) and added to the socket error queue of the skb, if the skb has a socket associated with it. The actual TX timestamp will reach userspace as a RX timestamp on the cloned packet. If timestamping is requested and no timestamping is done in the device driver (potentially this may use hardware timestamping), it will be done in software after the device's start_hard_xmit routine. Signed-off-by: Patrick Ohly <patrick.ohly@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-01net: add ARP notify option for devicesStephen Hemminger1-0/+6
This adds another inet device option to enable gratuitous ARP when device is brought up or address change. This is handy for clusters or virtualization. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-31Merge branch 'master' of ↵David S. Miller1-19/+6
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/e1000/e1000_main.c
2009-01-30net: update documentation ip aliasesStephen Hemminger1-19/+6
This documentation is old. Add a short note to describe why aliases are no long necessary, and remove the old contact/edit info. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-27Merge branch 'master' of ↵David S. Miller1-1/+2
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
2009-01-26networking: document "nc" in addition to "netcat" in netconsole.txtJesse Barnes1-1/+2
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>
2009-01-22dccp: Implement both feature-local and feature-remote Sequence Window featureGerrit Renker1-1/+2
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 Schwarzer1-1/+1
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 Schwarzer1-1/+1
- (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 Renker1-3/+0
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 Renker1-3/+0
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 Renker1-2/+3
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 Chen2-2/+2
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>
2008-11-24dccp: Set per-connection CCIDs via socket optionsGerrit Renker1-0/+14
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 Hałasa1-4/+4
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2008-11-21mac80211_hwsim: Update documentation (AP mode enabled)Jouni Malinen1-4/+5
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>
2008-11-21Merge branch 'master' of ↵David S. Miller1-1/+1
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
2008-11-20phylib: fix phy name example in documentationPaulius Zaleckas1-1/+1
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>
2008-11-17dccp: Deprecate Ack Ratio sysctlGerrit Renker1-3/+0
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>