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* tcp: fix tcp_trim_head() to adjust segment count with skb MSSNeal Cardwell2012-01-301-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | This commit fixes tcp_trim_head() to recalculate the number of segments in the skb with the skb's existing MSS, so trimming the head causes the skb segment count to be monotonically non-increasing - it should stay the same or go down, but not increase. Previously tcp_trim_head() used the current MSS of the connection. But if there was a decrease in MSS between original transmission and ACK (e.g. due to PMTUD), this could cause tcp_trim_head() to counter-intuitively increase the segment count when trimming bytes off the head of an skb. This violated assumptions in tcp_tso_acked() that tcp_trim_head() only decreases the packet count, so that packets_acked in tcp_tso_acked() could underflow, leading tcp_clean_rtx_queue() to pass u32 pkts_acked values as large as 0xffffffff to ca_ops->pkts_acked(). As an aside, if tcp_trim_head() had really wanted the skb to reflect the current MSS, it should have called tcp_set_skb_tso_segs() unconditionally, since a decrease in MSS would mean that a single-packet skb should now be sliced into multiple segments. Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Nandita Dukkipati <nanditad@google.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
* foundations of per-cgroup memory pressure controlling.Glauber Costa2011-12-121-1/+1
| | | | | | | | | | | | | | | | | This patch replaces all uses of struct sock fields' memory_pressure, memory_allocated, sockets_allocated, and sysctl_mem to acessor macros. Those macros can either receive a socket argument, or a mem_cgroup argument, depending on the context they live in. Since we're only doing a macro wrapping here, no performance impact at all is expected in the case where we don't have cgroups disabled. Signed-off-by: Glauber Costa <glommer@parallels.com> Reviewed-by: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com> CC: David S. Miller <davem@davemloft.net> CC: Eric W. Biederman <ebiederm@xmission.com> CC: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: fix tcp_trim_head()Eric Dumazet2011-12-051-5/+8
| | | | | | | | | | | | | | commit f07d960df3 (tcp: avoid frag allocation for small frames) breaked assumption in tcp stack that skb is either linear (skb->data_len == 0), or fully fragged (skb->data_len == skb->len) tcp_trim_head() made this assumption, we must fix it. Thanks to Vijay for providing a very detailed explanation. Reported-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: take care of misalignmentsEric Dumazet2011-12-041-1/+9
| | | | | | | | | | | | | | | | | | | | | We discovered that TCP stack could retransmit misaligned skbs if a malicious peer acknowledged sub MSS frame. This currently can happen only if output interface is non SG enabled : If SG is enabled, tcp builds headless skbs (all payload is included in fragments), so the tcp trimming process only removes parts of skb fragments, header stay aligned. Some arches cant handle misalignments, so force a head reallocation and shrink headroom to MAX_TCP_HEADER. Dont care about misaligments on x86 and PPC (or other arches setting NET_IP_ALIGN to 0) This patch introduces __pskb_copy() which can specify the headroom of new head, and pskb_copy() becomes a wrapper on top of __pskb_copy() Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: do not scale TSO segment size with reordering degreeNeal Cardwell2011-11-291-1/+1
| | | | | | | | | | | | | | | | Since 2005 (c1b4a7e69576d65efc31a8cea0714173c2841244) tcp_tso_should_defer has been using tcp_max_burst() as a target limit for deciding how large to make outgoing TSO packets when not using sysctl_tcp_tso_win_divisor. But since 2008 (dd9e0dda66ba38a2ddd1405ac279894260dc5c36) tcp_max_burst() returns the reordering degree. We should not have tcp_tso_should_defer attempt to build larger segments just because there is more reordering. This commit splits the notion of deferral size used in TSO from the notion of burst size used in cwnd moderation, and returns the TSO deferral limit to its original value. Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: Fix comments for Nagle algorithmFeng King2011-11-081-1/+1
| | | | | | | | TCP_NODELAY is weaker than TCP_CORK, when TCP_CORK was set, small segments will always pass Nagle test regardless of TCP_NODELAY option. Signed-off-by: Feng King <kinwin2008@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: add const qualifiers where possibleEric Dumazet2011-10-211-35/+37
| | | | | | | | | | | | Adding const qualifiers to pointers can ease code review, and spot some bugs. It might allow compiler to optimize code further. For example, is it legal to temporary write a null cksum into tcphdr in tcp_md5_hash_header() ? I am afraid a sniffer could catch the temporary null value... Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: add skb frag size accessorsEric Dumazet2011-10-191-3/+5
| | | | | | | | | | | To ease skb->truesize sanitization, its better to be able to localize all references to skb frags size. Define accessors : skb_frag_size() to fetch frag size, and skb_frag_size_{set|add|sub}() to manipulate it. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: rename tcp_skb_cb flagsEric Dumazet2011-09-271-31/+32
| | | | | | | | | | Rename struct tcp_skb_cb "flags" to "tcp_flags" to ease code review and maintenance. Its content is a combination of FIN/SYN/RST/PSH/ACK/URG/ECE/CWR flags Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Proportional Rate Reduction for TCP.Nandita Dukkipati2011-08-241-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements Proportional Rate Reduction (PRR) for TCP. PRR is an algorithm that determines TCP's sending rate in fast recovery. PRR avoids excessive window reductions and aims for the actual congestion window size at the end of recovery to be as close as possible to the window determined by the congestion control algorithm. PRR also improves accuracy of the amount of data sent during loss recovery. The patch implements the recommended flavor of PRR called PRR-SSRB (Proportional rate reduction with slow start reduction bound) and replaces the existing rate halving algorithm. PRR improves upon the existing Linux fast recovery under a number of conditions including: 1) burst losses where the losses implicitly reduce the amount of outstanding data (pipe) below the ssthresh value selected by the congestion control algorithm and, 2) losses near the end of short flows where application runs out of data to send. As an example, with the existing rate halving implementation a single loss event can cause a connection carrying short Web transactions to go into the slow start mode after the recovery. This is because during recovery Linux pulls the congestion window down to packets_in_flight+1 on every ACK. A short Web response often runs out of new data to send and its pipe reduces to zero by the end of recovery when all its packets are drained from the network. Subsequent HTTP responses using the same connection will have to slow start to raise cwnd to ssthresh. PRR on the other hand aims for the cwnd to be as close as possible to ssthresh by the end of recovery. A description of PRR and a discussion of its performance can be found at the following links: - IETF Draft: http://tools.ietf.org/html/draft-mathis-tcpm-proportional-rate-reduction-01 - IETF Slides: http://www.ietf.org/proceedings/80/slides/tcpm-6.pdf http://tools.ietf.org/agenda/81/slides/tcpm-2.pdf - Paper to appear in Internet Measurements Conference (IMC) 2011: Improving TCP Loss Recovery Nandita Dukkipati, Matt Mathis, Yuchung Cheng Signed-off-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: ipv4: convert to SKB frag APIsIan Campbell2011-08-241-1/+1
| | | | | | | | | | | | Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: Pass flowi to ->queue_xmit().David S. Miller2011-05-081-1/+1
| | | | | | | | | | | This allows us to acquire the exact route keying information from the protocol, however that might be managed. It handles all of the possibilities, from the simplest case of storing the key in inet->cork.fl to the more complex setup SCTP has where individual transports determine the flow. Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6Linus Torvalds2011-04-071-1/+1
|\ | | | | | | | | * 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6: Fix common misspellings
| * Fix common misspellingsLucas De Marchi2011-03-311-1/+1
| | | | | | | | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* | tcp: len check is unnecessarily devastating, change to WARN_ONIlpo Järvinen2011-04-011-1/+2
|/ | | | | | | | | | | All callers are prepared for alloc failures anyway, so this error can safely be boomeranged to the callers domain without super bad consequences. ...At worst the connection might go into a state where each RTO tries to (unsuccessfully) re-fragment with such a mis-sized value and eventually dies. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: undo_retrans counter fixesYuchung Cheng2011-02-211-1/+1
| | | | | | | | | | | | | | | | Fix a bug that undo_retrans is incorrectly decremented when undo_marker is not set or undo_retrans is already 0. This happens when sender receives more DSACK ACKs than packets retransmitted during the current undo phase. This may also happen when sender receives DSACK after the undo operation is completed or cancelled. Fix another bug that undo_retrans is incorrectly incremented when sender retransmits an skb and tcp_skb_pcount(skb) > 1 (TSO). This case is rare but not impossible. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'for-next' of ↵Linus Torvalds2011-01-131-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits) Documentation/trace/events.txt: Remove obsolete sched_signal_send. writeback: fix global_dirty_limits comment runtime -> real-time ppc: fix comment typo singal -> signal drivers: fix comment typo diable -> disable. m68k: fix comment typo diable -> disable. wireless: comment typo fix diable -> disable. media: comment typo fix diable -> disable. remove doc for obsolete dynamic-printk kernel-parameter remove extraneous 'is' from Documentation/iostats.txt Fix spelling milisec -> ms in snd_ps3 module parameter description Fix spelling mistakes in comments Revert conflicting V4L changes i7core_edac: fix typos in comments mm/rmap.c: fix comment sound, ca0106: Fix assignment to 'channel'. hrtimer: fix a typo in comment init/Kconfig: fix typo anon_inodes: fix wrong function name in comment fix comment typos concerning "consistent" poll: fix a typo in comment ... Fix up trivial conflicts in: - drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c) - fs/ext4/ext4.h Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
| * Merge branch 'master' into for-nextJiri Kosina2010-12-221-19/+23
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: MAINTAINERS arch/arm/mach-omap2/pm24xx.c drivers/scsi/bfa/bfa_fcpim.c Needed to update to apply fixes for which the old branch was too outdated.
| * | tree-wide: fix comment/printk typosUwe Kleine-König2010-11-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "gadget", "through", "command", "maintain", "maintain", "controller", "address", "between", "initiali[zs]e", "instead", "function", "select", "already", "equal", "access", "management", "hierarchy", "registration", "interest", "relative", "memory", "offset", "already", Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | TCP: increase default initial receive window.Nandita Dukkipati2010-12-201-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch changes the default initial receive window to 10 mss (defined constant). The default window is limited to the maximum of 10*1460 and 2*mss (when mss > 1460). draft-ietf-tcpm-initcwnd-00 is a proposal to the IETF that recommends increasing TCP's initial congestion window to 10 mss or about 15KB. Leading up to this proposal were several large-scale live Internet experiments with an initial congestion window of 10 mss (IW10), where we showed that the average latency of HTTP responses improved by approximately 10%. This was accompanied by a slight increase in retransmission rate (0.5%), most of which is coming from applications opening multiple simultaneous connections. To understand the extreme worst case scenarios, and fairness issues (IW10 versus IW3), we further conducted controlled testbed experiments. We came away finding minimal negative impact even under low link bandwidths (dial-ups) and small buffers. These results are extremely encouraging to adopting IW10. However, an initial congestion window of 10 mss is useless unless a TCP receiver advertises an initial receive window of at least 10 mss. Fortunately, in the large-scale Internet experiments we found that most widely used operating systems advertised large initial receive windows of 64KB, allowing us to experiment with a wide range of initial congestion windows. Linux systems were among the few exceptions that advertised a small receive window of 6KB. The purpose of this patch is to fix this shortcoming. References: 1. A comprehensive list of all IW10 references to date. http://code.google.com/speed/protocols/tcpm-IW10.html 2. Paper describing results from large-scale Internet experiments with IW10. http://ccr.sigcomm.org/drupal/?q=node/621 3. Controlled testbed experiments under worst case scenarios and a fairness study. http://www.ietf.org/proceedings/79/slides/tcpm-0.pdf 4. Raw test data from testbed experiments (Linux senders/receivers) with initial congestion and receive windows of both 10 mss. http://research.csc.ncsu.edu/netsrv/?q=content/iw10 5. Internet-Draft. Increasing TCP's Initial Window. https://datatracker.ietf.org/doc/draft-ietf-tcpm-initcwnd/ Signed-off-by: Nandita Dukkipati <nanditad@google.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Abstract default ADVMSS behind an accessor.David S. Miller2010-12-131-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make all RTAX_ADVMSS metric accesses go through a new helper function, dst_metric_advmss(). Leave the actual default metric as "zero" in the real metric slot, and compute the actual default value dynamically via a new dst_ops AF specific callback. For stacked IPSEC routes, we use the advmss of the path which preserves existing behavior. Unlike ipv4/ipv6, DecNET ties the advmss to the mtu and thus updates advmss on pmtu updates. This inconsistency in advmss handling results in more raw metric accesses than I wish we ended up with. Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge branch 'master' of ↵David S. Miller2010-12-081-19/+23
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/ath/ath9k/ar9003_eeprom.c net/llc/af_llc.c
| * | tcp: protect sysctl_tcp_cookie_size readsEric Dumazet2010-12-081-12/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure sysctl_tcp_cookie_size is read once in tcp_cookie_size_check(), or we might return an illegal value to caller if sysctl_tcp_cookie_size is changed by another cpu. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: William Allen Simpson <william.allen.simpson@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp: avoid a possible divide by zeroEric Dumazet2010-12-081-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | sysctl_tcp_tso_win_divisor might be set to zero while one cpu runs in tcp_tso_should_defer(). Make sure we dont allow a divide by zero by reading sysctl_tcp_tso_win_divisor exactly once. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp: Bug fix in initialization of receive window.Nandita Dukkipati2010-12-081-5/+4
| |/ | | | | | | | | | | | | | | | | | | | | The bug has to do with boundary checks on the initial receive window. If the initial receive window falls between init_cwnd and the receive window specified by the user, the initial window is incorrectly brought down to init_cwnd. The correct behavior is to allow it to remain unchanged. Signed-off-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: use TCP_BASE_MSS to set basic mss valueShan Wei2010-12-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TCP_BASE_MSS is defined, but not used. commit 5d424d5a introduce this macro, so use it to initial sysctl_tcp_base_mss. commit 5d424d5a674f782d0659a3b66d951f412901faee Author: John Heffner <jheffner@psc.edu> Date: Mon Mar 20 17:53:41 2006 -0800 [TCP]: MTU probing Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | xps: Improvements in TX queue selectionTom Herbert2010-11-241-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In dev_pick_tx, don't do work in calculating queue index or setting the index in the sock unless the device has more than one queue. This allows the sock to be set only with a queue index of a multi-queue device which is desirable if device are stacked like in a tunnel. We also allow the mapping of a socket to queue to be changed. To maintain in order packet transmission a flag (ooo_okay) has been added to the sk_buff structure. If a transport layer sets this flag on a packet, the transmit queue can be changed for the socket. Presumably, the transport would set this if there was no possbility of creating OOO packets (for instance, there are no packets in flight for the socket). This patch includes the modification in TCP output for setting this flag. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | network: tcp_connect should return certain errors up the stackEric Paris2010-11-171-1/+4
|/ | | | | | | | | | | | The current tcp_connect code completely ignores errors from sending an skb. This makes sense in many situations (like -ENOBUFFS) but I want to be able to immediately fail connections if they are denied by the SELinux netfilter hook. Netfilter does not normally return ECONNREFUSED when it drops a packet so we respect that error code as a final and fatal error that can not be recovered. Based-on-patch-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: return operator cleanupEric Dumazet2010-09-231-4/+4
| | | | | | | | | Change "return (EXPR);" to "return EXPR;" return is not a function, parentheses are not required. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: update also tcp_output with regard to RFC 5681Gerrit Renker2010-09-011-9/+3
| | | | | | | | Thanks to Ilpo Jarvinen, this updates also the initial window setting for tcp_output with regard to RFC 5681. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: allow effective reduction of TCP's rcv-buffer via setsockoptHagen Paul Pfeifer2010-08-221-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Via setsockopt it is possible to reduce the socket RX buffer (SO_RCVBUF). TCP method to select the initial window and window scaling option in tcp_select_initial_window() currently misbehaves and do not consider a reduced RX socket buffer via setsockopt. Even though the server's RX buffer is reduced via setsockopt() to 256 byte (Initial Window 384 byte => 256 * 2 - (256 * 2 / 4)) the window scale option is still 7: 192.168.1.38.40676 > 78.47.222.210.5001: Flags [S], seq 2577214362, win 5840, options [mss 1460,sackOK,TS val 338417 ecr 0,nop,wscale 0], length 0 78.47.222.210.5001 > 192.168.1.38.40676: Flags [S.], seq 1570631029, ack 2577214363, win 384, options [mss 1452,sackOK,TS val 2435248895 ecr 338417,nop,wscale 7], length 0 192.168.1.38.40676 > 78.47.222.210.5001: Flags [.], ack 1, win 5840, options [nop,nop,TS val 338421 ecr 2435248895], length 0 Within tcp_select_initial_window() the original space argument - a representation of the rx buffer size - is expanded during tcp_select_initial_window(). Only sysctl_tcp_rmem[2], sysctl_rmem_max and window_clamp are considered to calculate the initial window. This patch adjust the window_clamp argument if the user explicitly reduce the receive buffer. Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net> Cc: David S. Miller <davem@davemloft.net> Cc: Patrick McHardy <kaber@trash.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'master' of ↵David S. Miller2010-07-201-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/vhost/net.c net/bridge/br_device.c Fix merge conflict in drivers/vhost/net.c with guidance from Stephen Rothwell. Revert the effects of net-2.6 commit 573201f36fd9c7c6d5218cdcd9948cee700b277d since net-next-2.6 has fixes that make bridge netpoll work properly thus we don't need it disabled. Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp: fix crash in tcp_xmit_retransmit_queueIlpo Järvinen2010-07-191-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It can happen that there are no packets in queue while calling tcp_xmit_retransmit_queue(). tcp_write_queue_head() then returns NULL and that gets deref'ed to get sacked into a local var. There is no work to do if no packets are outstanding so we just exit early. This oops was introduced by 08ebd1721ab8fd (tcp: remove tp->lost_out guard to make joining diff nicer). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Reported-by: Lennart Schulte <lennart.schulte@nets.rwth-aachen.de> Tested-by: Lennart Schulte <lennart.schulte@nets.rwth-aachen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net/ipv4: EXPORT_SYMBOL cleanupsEric Dumazet2010-07-121-7/+5
| | | | | | | | | | | | | | | | | | CodingStyle cleanups EXPORT_SYMBOL should immediately follow the symbol declaration. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: tso_fragment() might avoid GFP_ATOMICEric Dumazet2010-06-281-3/+3
| | | | | | | | | | | | | | | | We can pass a gfp argument to tso_fragment() and avoid GFP_ATOMIC allocations sometimes. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: unify tcp flag macrosChangli Gao2010-06-151-30/+29
|/ | | | | | | | | | | | | | | | | unify tcp flag macros: TCPHDR_FIN, TCPHDR_SYN, TCPHDR_RST, TCPHDR_PSH, TCPHDR_ACK, TCPHDR_URG, TCPHDR_ECE and TCPHDR_CWR. TCBCB_FLAG_* are replaced with the corresponding TCPHDR_*. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- include/net/tcp.h | 24 ++++++------- net/ipv4/tcp.c | 8 ++-- net/ipv4/tcp_input.c | 2 - net/ipv4/tcp_output.c | 59 ++++++++++++++++----------------- net/netfilter/nf_conntrack_proto_tcp.c | 32 ++++++----------- net/netfilter/xt_TCPMSS.c | 4 -- 6 files changed, 58 insertions(+), 71 deletions(-) Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: tcp_synack_options() fix Eric Dumazet2010-05-171-5/+4
| | | | | | | | | | | | | | | | | | | Commit 33ad798c924b4a (tcp: options clean up) introduced a problem if MD5+SACK+timestamps were used in initial SYN message. Some stacks (old linux for example) try to negotiate MD5+SACK+TSTAMP sessions, but since 40 bytes of tcp options space are not enough to store all the bits needed, we chose to disable timestamps in this case. We send a SYN-ACK _without_ timestamp option, but socket has timestamps enabled and all further outgoing messages contain a TS block, all with the initial timestamp of the remote peer. Fix is to really disable timestamps option for the whole session. Reported-by: Bijay Singh <Bijay.Singh@guavus.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Introduce sk_route_nocapsEric Dumazet2010-05-161-1/+1
| | | | | | | | | | | | | | | | | | | | | TCP-MD5 sessions have intermittent failures, when route cache is invalidated. ip_queue_xmit() has to find a new route, calls sk_setup_caps(sk, &rt->u.dst), destroying the sk->sk_route_caps &= ~NETIF_F_GSO_MASK that MD5 desperately try to make all over its way (from tcp_transmit_skb() for example) So we send few bad packets, and everything is fine when tcp_transmit_skb() is called again for this socket. Since ip_queue_xmit() is at a lower level than TCP-MD5, I chose to use a socket field, sk_route_nocaps, containing bits to mask on sk_route_caps. Reported-by: Bhaskar Dutta <bhaskie@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: fix outsegs stat for TSO segmentsTom Herbert2010-04-221-2/+3
| | | | | | | | | Account for TSO segments of an skb in TCP_MIB_OUTSEGS counter. Without doing this, the counter can be off by orders of magnitude from the actual number of segments sent. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Fix various endianness glitchesEric Dumazet2010-04-201-2/+2
| | | | | | | | Sparse can help us find endianness bugs, but we need to make some cleanups to be able to more easily spot real bugs. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: replace ipfragok with skb->local_dfShan Wei2010-04-151-1/+1
| | | | | | | | | | | As Herbert Xu said: we should be able to simply replace ipfragok with skb->local_df. commit f88037(sctp: Drop ipfargok in sctp_xmit function) has droped ipfragok and set local_df value properly. The patch kills the ipfragok parameter of .queue_xmit(). Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: Set CHECKSUM_UNNECESSARY in tcp_init_nondata_skbDavid S. Miller2010-04-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Back in commit 04a0551c87363f100b04d28d7a15a632b70e18e7 ("loopback: Drop obsolete ip_summed setting") we stopped setting CHECKSUM_UNNECESSARY in the loopback xmit. This is because such a setting was a lie since it implies that the checksum field of the packet is properly filled in. Instead what happens normally is that CHECKSUM_PARTIAL is set and skb->csum is calculated as needed. But this was only happening for TCP data packets (via the skb->ip_summed assignment done in tcp_sendmsg()). It doesn't happen for non-data packets like ACKs etc. Fix this by setting skb->ip_summed in the common non-data packet constructor. It already is setting skb->csum to zero. But this reminds us that we still have things like ip_output.c's ip_dev_loopback_xmit() which sets skb->ip_summed to the value CHECKSUM_UNNECESSARY, which Herbert's patch teaches us is not valid. So we'll have to address that at some point too. Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: Remove unused send_check length argumentHerbert Xu2010-04-111-1/+1
| | | | | | | | | | | inet: Remove unused send_check length argument This patch removes the unused length argument from the send_check function in struct inet_connection_sock_af_ops. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Yinghai <yinghai.lu@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* tcp: Fix tcp_make_synack()Eric Dumazet2010-03-081-9/+9
| | | | | | | | | | | | Commit 4957faad (TCPCT part 1g: Responder Cookie => Initiator), part of TCP_COOKIE_TRANSACTION implementation, forgot to correctly size synack skb in case user data must be included. Many thanks to Mika Pentillä for spotting this error. Reported-by: Penttillä Mika <mika.penttila@ixonos.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Add rtnetlink init_rcvwnd to set the TCP initial receive windowlaurent chavey2009-12-231-4/+13
| | | | | | | | | | | | | | | | | | | Add rtnetlink init_rcvwnd to set the TCP initial receive window size advertised by passive and active TCP connections. The current Linux TCP implementation limits the advertised TCP initial receive window to the one prescribed by slow start. For short lived TCP connections used for transaction type of traffic (i.e. http requests), bounding the advertised TCP initial receive window results in increased latency to complete the transaction. Support for setting initial congestion window is already supported using rtnetlink init_cwnd, but the feature is useless without the ability to set a larger TCP initial receive window. The rtnetlink init_rcvwnd allows increasing the TCP initial receive window, allowing TCP connection to advertise larger TCP receive window than the ones bounded by slow start. Signed-off-by: Laurent Chavey <chavey@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: Remove check in __tcp_push_pending_framesKrishna Kumar2009-12-231-5/+0
| | | | | | | | | | | | | | | tcp_push checks tcp_send_head and calls __tcp_push_pending_frames, which again checks tcp_send_head, and this unnecessary check is done for every other caller of __tcp_push_pending_frames. Remove tcp_send_head check in __tcp_push_pending_frames and add the check to tcp_push_pending_frames. Other functions call __tcp_push_pending_frames only when tcp_send_head would evaluate to true. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: Revert per-route SACK/DSACK/TIMESTAMP changes.David S. Miller2009-12-151-13/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It creates a regression, triggering badness for SYN_RECV sockets, for example: [19148.022102] Badness at net/ipv4/inet_connection_sock.c:293 [19148.022570] NIP: c02a0914 LR: c02a0904 CTR: 00000000 [19148.023035] REGS: eeecbd30 TRAP: 0700 Not tainted (2.6.32) [19148.023496] MSR: 00029032 <EE,ME,CE,IR,DR> CR: 24002442 XER: 00000000 [19148.024012] TASK = eee9a820[1756] 'privoxy' THREAD: eeeca000 This is likely caused by the change in the 'estab' parameter passed to tcp_parse_options() when invoked by the functions in net/ipv4/tcp_minisocks.c But even if that is fixed, the ->conn_request() changes made in this patch series is fundamentally wrong. They try to use the listening socket's 'dst' to probe the route settings. The listening socket doesn't even have a route, and you can't get the right route (the child request one) until much later after we setup all of the state, and it must be done by hand. This stuff really isn't ready, so the best thing to do is a full revert. This reverts the following commits: f55017a93f1a74d50244b1254b9a2bd7ac9bbf7d 022c3f7d82f0f1c68018696f2f027b87b9bb45c2 1aba721eba1d84a2defce45b950272cee1e6c72a cda42ebd67ee5fdf09d7057b5a4584d36fe8a335 345cda2fd695534be5a4494f1b59da9daed33663 dc343475ed062e13fc260acccaab91d7d80fd5b2 05eaade2782fb0c90d3034fd7a7d5a16266182bb 6a2a2d6bf8581216e08be15fcb563cfd6c430e1e Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: sysctl_tcp_cookie_size needs to be exported to modules.David S. Miller2009-12-021-0/+1
| | | | | | | | | Otherwise: ERROR: "sysctl_tcp_cookie_size" [net/ipv6/ipv6.ko] undefined! make[1]: *** [__modpost] Error 1 Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: Fix warning on 64-bit.David S. Miller2009-12-021-1/+1
| | | | | | | net/ipv4/tcp_output.c: In function ‘tcp_make_synack’: net/ipv4/tcp_output.c:2488: warning: cast from pointer to integer of different size Signed-off-by: David S. Miller <davem@davemloft.net>
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