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2009-03-18tcp: remove parameter from tcp_recv_urg().Rami Rosen
This patch removes an unused parameter (addr_len) from tcp_recv_urg() method in net/ipv4/tcp.c. Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-15tcp: make sure xmit goal size never becomes zeroIlpo Järvinen
It's not too likely to happen, would basically require crafted packets (must hit the max guard in tcp_bound_to_half_wnd()). It seems that nothing that bad would happen as there's tcp_mems and congestion window that prevent runaway at some point from hurting all too much (I'm not that sure what all those zero sized segments we would generate do though in write queue). Preventing it regardless is certainly the best way to go. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-15tcp: cache result of earlier divides when mss-aligning thingsIlpo Järvinen
The results is very unlikely change every so often so we hardly need to divide again after doing that once for a connection. Yet, if divide still becomes necessary we detect that and do the right thing and again settle for non-divide state. Takes the u16 space which was previously taken by the plain xmit_size_goal. This should take care part of the tso vs non-tso difference we found earlier. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-15tcp: simplify tcp_current_mssIlpo Järvinen
There's very little need for most of the callsites to get tp->xmit_goal_size updated. That will cost us divide as is, so slice the function in two. Also, the only users of the tp->xmit_goal_size are directly behind tcp_current_mss(), so there's no need to store that variable into tcp_sock at all! The drop of xmit_goal_size currently leaves 16-bit hole and some reorganization would again be necessary to change that (but I'm aiming to fill that hole with u16 xmit_goal_size_segs to cache the results of the remaining divide to get that tso on regression). Bring xmit_goal_size parts into tcp.c Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-02tcp: in sendmsg/pages open code the real goto targetIlpo Järvinen
copied was assigned zero right before the goto, so if (copied) cannot ever be true. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-08gro: Optimise TCP packet receptionHerbert Xu
gro: Optimise TCP packet reception As this function can be called more than half a million times for 10GbE, it's important to optimise it as much as we can. This patch uses bit ops to logical ops, as well as open coding memcmp to exploit alignment properties. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-30Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/e1000/e1000_main.c
2009-01-29gro: Avoid copying headers of unmerged packetsHerbert Xu
Unfortunately simplicity isn't always the best. The fraginfo interface turned out to be suboptimal. The problem was quite obvious. For every packet, we have to copy the headers from the frags structure into skb->head, even though for 99% of the packets this part is immediately thrown away after the merge. LRO didn't have this problem because it directly read the headers from the frags structure. This patch attempts to address this by creating an interface that allows GRO to access the headers in the first frag without having to copy it. Because all drivers that use frags place the headers in the first frag this optimisation should be enough. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-26tcp: Fix length tcp_splice_data_recv passes to skb_splice_bits.Dimitris Michailidis
tcp_splice_data_recv has two lengths to consider: the len parameter it gets from tcp_read_sock, which specifies the amount of data in the skb, and rd_desc->count, which is the amount of data the splice caller still wants. Currently it passes just the latter to skb_splice_bits, which then splices min(rd_desc->count, skb->len - offset) bytes. Most of the time this is fine, except when the skb contains urgent data. In that case len goes only up to the urgent byte and is less than skb->len - offset. By ignoring len tcp_splice_data_recv may a) splice data tcp_read_sock told it not to, b) return to tcp_read_sock a value > len. Now, tcp_read_sock doesn't handle used > len and leaves the socket in a bad state (both sk_receive_queue and copied_seq are bad at that point) resulting in duplicated data and corruption. Fix by passing min(rd_desc->count, len) to skb_splice_bits. Signed-off-by: Dimitris Michailidis <dm@chelsio.com> Acked-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-14gso: Ensure that the packet is long enoughHerbert Xu
When we get a GSO packet from an untrusted source, we need to ensure that it is sufficiently long so that we don't end up crashing. Based on discovery and patch by Ian Campbell. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-13tcp: splice as many packets as possible at onceWilly Tarreau
As spotted by Willy Tarreau, current splice() from tcp socket to pipe is not optimal. It processes at most one segment per call. This results in low performance and very high overhead due to syscall rate when splicing from interfaces which do not support LRO. Willy provided a patch inside tcp_splice_read(), but a better fix is to let tcp_read_sock() process as many segments as possible, so that tcp_rcv_space_adjust() and tcp_cleanup_rbuf() are called less often. With this change, splice() behaves like tcp_recvmsg(), being able to consume many skbs in one system call. With typical 1460 bytes of payload per frame, that means splice(SPLICE_F_NONBLOCK) can return 16*1460 = 23360 bytes. Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-09Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (22 commits) ioat: fix self test for multi-channel case dmaengine: bump initcall level to arch_initcall dmaengine: advertise all channels on a device to dma_filter_fn dmaengine: use idr for registering dma device numbers dmaengine: add a release for dma class devices and dependent infrastructure ioat: do not perform removal actions at shutdown iop-adma: enable module removal iop-adma: kill debug BUG_ON iop-adma: let devm do its job, don't duplicate free dmaengine: kill enum dma_state_client dmaengine: remove 'bigref' infrastructure dmaengine: kill struct dma_client and supporting infrastructure dmaengine: replace dma_async_client_register with dmaengine_get atmel-mci: convert to dma_request_channel and down-level dma_slave dmatest: convert to dma_request_channel dmaengine: introduce dma_request_channel and private channels net_dma: convert to dma_find_channel dmaengine: provide a common 'issue_pending_all' implementation dmaengine: centralize channel allocation, introduce dma_find_channel dmaengine: up-level reference counting to the module level ...
2009-01-08tcp6: Add GRO supportHerbert Xu
This patch adds GRO support for TCP over IPv6. The code is exactly the same as the IPv4 version except for the pseudo-header checksum computation. Note that I've removed the unused tcphdr argument from tcp_v6_check rather than invent a bogus value for GRO. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-06net_dma: convert to dma_find_channelDan Williams
Use the general-purpose channel allocation provided by dmaengine. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: up-level reference counting to the module levelDan Williams
Simply, if a client wants any dmaengine channel then prevent all dmaengine modules from being removed. Once the clients are done re-enable module removal. Why?, beyond reducing complication: 1/ Tracking reference counts per-transaction in an efficient manner, as is currently done, requires a complicated scheme to avoid cache-line bouncing effects. 2/ Per-transaction ref-counting gives the false impression that a dma-driver can be gracefully removed ahead of its user (net, md, or dma-slave) 3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but if such an engine were built one day we still would not need to notify clients of remove events. The driver can simply return NULL to a ->prep() request, something that is much easier for a client to handle. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-05tcp: Kill extraneous SPLICE_F_NONBLOCK checks.David S. Miller
In splice TCP receive, the SPLICE_F_NONBLOCK flag is used to compute the "timeo" value. So checking it again inside of the main receive loop to trigger -EAGAIN processing is entirely unnecessary. Noticed by Jarek P. and Lennert Buytenhek. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-05tcp: don't mask EOF and socket errors on nonblocking splice receiveLennert Buytenhek
Currently, setting SPLICE_F_NONBLOCK on splice from a TCP socket results in masking of EOF (RDHUP) and error conditions on the socket by an -EAGAIN return. Move the NONBLOCK check in tcp_splice_read() to be after the EOF and error checks to fix this. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-04gro: Use gso_size to store MSSHerbert Xu
In order to allow GRO packets without frag_list at all, we need to store the MSS in the packet itself. The obvious place is gso_size. The only thing to watch out for is if the packet ends up not being GRO then we need to clear gso_size before pushing the packet into the stack. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-29net: Fix percpu counters deadlockHerbert Xu
When we converted the protocol atomic counters such as the orphan count and the total socket count deadlocks were introduced due to the mismatch in BH status of the spots that used the percpu counter operations. Based on the diagnosis and patch by Peter Zijlstra, this patch fixes these issues by disabling BH where we may be in process context. Reported-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Tested-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15tcp: Add GRO supportHerbert Xu
This patch adds the TCP-specific portion of GRO. The criterion for merging is extremely strict (the TCP header must match exactly apart from the checksum) so as to allow refragmentation. Otherwise this is pretty much identical to LRO, except that we support the merging of ECN packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-25net: Use a percpu_counter for orphan_countEric Dumazet
Instead of using one atomic_t per protocol, use a percpu_counter for "orphan_count", to reduce cache line contention on heavy duty network servers. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-25net: Use a percpu_counter for sockets_allocatedEric Dumazet
Instead of using one atomic_t per protocol, use a percpu_counter for "sockets_allocated", to reduce cache line contention on heavy duty network servers. Note : We revert commit (248969ae31e1b3276fc4399d67ce29a5d81e6fd9 net: af_unix can make unix_nr_socks visbile in /proc), since it is not anymore used after sock_prot_inuse_add() addition Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16net: Convert TCP & DCCP hash tables to use RCU / hlist_nullsEric Dumazet
RCU was added to UDP lookups, using a fast infrastructure : - sockets kmem_cache use SLAB_DESTROY_BY_RCU and dont pay the price of call_rcu() at freeing time. - hlist_nulls permits to use few memory barriers. This patch uses same infrastructure for TCP/DCCP established and timewait sockets. Thanks to SLAB_DESTROY_BY_RCU, no slowdown for applications using short lived TCP connections. A followup patch, converting rwlocks to spinlocks will even speedup this case. __inet_lookup_established() is pretty fast now we dont have to dirty a contended cache line (read_lock/read_unlock) Only established and timewait hashtable are converted to RCU (bind table and listen table are still using traditional locking) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-06Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/ath5k/base.c net/8021q/vlan_core.c
2008-11-05tcp: Fix recvmsg MSG_PEEK influence of blocking behavior.David S. Miller
Vito Caputo noticed that tcp_recvmsg() returns immediately from partial reads when MSG_PEEK is used. In particular, this means that SO_RCVLOWAT is not respected. Simply remove the test. And this matches the behavior of several other systems, including BSD. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-03net: clean up net/ipv4/ipip.c raw.c tcp.c tcp_minisocks.c tcp_yeah.c ↵Jianjun Kong
xfrm4_policy.c Signed-off-by: Jianjun Kong <jianjun@zeuux.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07tcp: kill pointless urg_modeIlpo Järvinen
It all started from me noticing that this urgent check in tcp_clean_rtx_queue is unnecessarily inside the loop. Then I took a longer look to it and found out that the users of urg_mode can trivially do without, well almost, there was one gotcha. Bonus: those funny people who use urg with >= 2^31 write_seq - snd_una could now rejoice too (that's the only purpose for the between being there, otherwise a simple compare would have done the thing). Not that I assume that the rest of the tcp code happily lives with such mind-boggling numbers :-). Alas, it turned out to be impossible to set wmem to such numbers anyway, yes I really tried a big sendfile after setting some wmem but nothing happened :-). ...Tcp_wmem is int and so is sk_sndbuf... So I hacked a bit variable to long and found out that it seems to work... :-) Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07net: wrap sk->sk_backlog_rcv()Peter Zijlstra
Wrap calling sk->sk_backlog_rcv() in a function. This will allow extending the generic sk_backlog_rcv behaviour. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-06tcp: Respect SO_RCVLOWAT in tcp_poll().David S. Miller
Based upon a report by Vito Caputo. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-25net: convert BUG_TRAP to generic WARN_ONIlpo Järvinen
Removes legacy reinvent-the-wheel type thing. The generic machinery integrates much better to automated debugging aids such as kerneloops.org (and others), and is unambiguous due to better naming. Non-intuively BUG_TRAP() is actually equal to WARN_ON() rather than BUG_ON() though some might actually be promoted to BUG_ON() but I left that to future. I could make at least one BUILD_BUG_ON conversion. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-19tcp: Fix MD5 signatures for non-linear skbsAdam Langley
Currently, the MD5 code assumes that the SKBs are linear and, in the case that they aren't, happily goes off and hashes off the end of the SKB and into random memory. Reported by Stephen Hemminger in [1]. Advice thanks to Stephen and Evgeniy Polyakov. Also includes a couple of missed route_caps from Stephen's patch in [2]. [1] http://marc.info/?l=linux-netdev&m=121445989106145&w=2 [2] http://marc.info/?l=linux-netdev&m=121459157816964&w=2 Signed-off-by: Adam Langley <agl@imperialviolet.org> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-18mib: put tcp statistics on struct netPavel Emelyanov
Proc temporary uses stats from init_net. BTW, TCP_XXX_STATS are beautiful (w/o do { } while (0) facing) again :) Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to NET_ADD_STATS_USERPavel Emelyanov
Done with NET_XXX_STATS macros :) To be continued... Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to NET_INC_STATS_USERPavel Emelyanov
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to NET_INC_STATS_BHPavel Emelyanov
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to NET_INC_STATSPavel Emelyanov
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16sock: add net to prot->enter_memory_pressure callbackPavel Emelyanov
The tcp_enter_memory_pressure calls NET_INC_STATS, but doesn't have where to get the net from. I decided to add a sk argument, not the net itself, only to factor all the required sock_net(sk) calls inside the enter_memory_pressure callback itself. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to TCP_DEC_STATSPavel Emelyanov
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to TCP_INC_STATS_BHPavel Emelyanov
Same as before - the sock is always there to get the net from, but there are also some places with the net already saved on the stack. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to TCP_INC_STATSPavel Emelyanov
Fortunately (almost) all the TCP code has a sock to get the net from :) Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16net/ipv4/tcp.c: Fix use of PULLHUP instead of POLLHUP in comments.Will Newton
Change PULLHUP to POLLHUP in tcp_poll comments and clean up another comment for grammar and coding style. Signed-off-by: Will Newton <will.newton@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/net/wan/hdlc_fr.c drivers/net/wireless/iwlwifi/iwl-4965.c drivers/net/wireless/iwlwifi/iwl3945-base.c
2008-07-03tcp: fix a size_t < 0 comparison in tcp_read_sockOctavian Purdila
<used> should be of type int (not size_t) since recv_actor can return negative values and it is also used in a < 0 comparison. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-03tcp: net/ipv4/tcp.c needs linux/scatterlist.hAndrew Morton
alpha: net/ipv4/tcp.c: In function 'tcp_calc_md5_hash': net/ipv4/tcp.c:2479: error: implicit declaration of function 'sg_init_table' net/ipv4/tcp.c:2482: error: implicit declaration of function 'sg_set_buf' net/ipv4/tcp.c:2507: error: implicit declaration of function 'sg_mark_end' Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-28Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/iwlwifi/iwl4965-base.c
2008-06-27tcp: calculate tcp_mem based on low memory instead of all memoryMiquel van Smoorenburg
The tcp_mem array which contains limits on the total amount of memory used by TCP sockets is calculated based on nr_all_pages. On a 32 bits x86 system, we should base this on the number of lowmem pages. Signed-off-by: Miquel van Smoorenburg <miquels@cistron.nl> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-13Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/smc911x.c
2008-06-12tcp: Revert 'process defer accept as established' changes.David S. Miller
This reverts two changesets, ec3c0982a2dd1e671bad8e9d26c28dcba0039d87 ("[TCP]: TCP_DEFER_ACCEPT updates - process as established") and the follow-on bug fix 9ae27e0adbf471c7a6b80102e38e1d5a346b3b38 ("tcp: Fix slab corruption with ipv6 and tcp6fuzz"). This change causes several problems, first reported by Ingo Molnar as a distcc-over-loopback regression where connections were getting stuck. Ilpo Järvinen first spotted the locking problems. The new function added by this code, tcp_defer_accept_check(), only has the child socket locked, yet it is modifying state of the parent listening socket. Fixing that is non-trivial at best, because we can't simply just grab the parent listening socket lock at this point, because it would create an ABBA deadlock. The normal ordering is parent listening socket --> child socket, but this code path would require the reverse lock ordering. Next is a problem noticed by Vitaliy Gusev, he noted: ---------------------------------------- >--- a/net/ipv4/tcp_timer.c >+++ b/net/ipv4/tcp_timer.c >@@ -481,6 +481,11 @@ static void tcp_keepalive_timer (unsigned long data) > goto death; > } > >+ if (tp->defer_tcp_accept.request && sk->sk_state == TCP_ESTABLISHED) { >+ tcp_send_active_reset(sk, GFP_ATOMIC); >+ goto death; Here socket sk is not attached to listening socket's request queue. tcp_done() will not call inet_csk_destroy_sock() (and tcp_v4_destroy_sock() which should release this sk) as socket is not DEAD. Therefore socket sk will be lost for freeing. ---------------------------------------- Finally, Alexey Kuznetsov argues that there might not even be any real value or advantage to these new semantics even if we fix all of the bugs: ---------------------------------------- Hiding from accept() sockets with only out-of-order data only is the only thing which is impossible with old approach. Is this really so valuable? My opinion: no, this is nothing but a new loophole to consume memory without control. ---------------------------------------- So revert this thing for now. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-11Merge branch 'net-next-2.6-misc-20080612a' of ↵David S. Miller
git://git.linux-ipv6.org/gitroot/yoshfuji/linux-2.6-next
2008-06-11net: remove CVS keywordsAdrian Bunk
This patch removes CVS keywords that weren't updated for a long time from comments. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>