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2012-12-09net: Handle encapsulated offloads before fragmentation or handing to lower devAlexander Duyck1-0/+4
This change allows the VXLAN to enable Tx checksum offloading even on devices that do not support encapsulated checksum offloads. The advantage to this is that it allows for the lower device to change due to routing table changes without impacting features on the VXLAN itself. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08ipv4: introduce rt_uses_gatewayJulian Anastasov1-2/+2
Add new flag to remember when route is via gateway. We will use it to allow rt_gateway to contain address of directly connected host for the cases when DST_NOCACHE is used or when the NH exception caches per-destination route without DST_NOCACHE flag, i.e. when routes are not used for other destinations. By this way we force the neighbour resolving to work with the routed destination but we can use different address in the packet, feature needed for IPVS-DR where original packet for virtual IP is routed via route to real IP. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-24net: use a per task frag allocatorEric Dumazet1-42/+28
We currently use a per socket order-0 page cache for tcp_sendmsg() operations. This page is used to build fragments for skbs. Its done to increase probability of coalescing small write() into single segments in skbs still in write queue (not yet sent) But it wastes a lot of memory for applications handling many mostly idle sockets, since each socket holds one page in sk->sk_sndmsg_page Its also quite inefficient to build TSO 64KB packets, because we need about 16 pages per skb on arches where PAGE_SIZE = 4096, so we hit page allocator more than wanted. This patch adds a per task frag allocator and uses bigger pages, if available. An automatic fallback is done in case of memory pressure. (up to 32768 bytes per frag, thats order-3 pages on x86) This increases TCP stream performance by 20% on loopback device, but also benefits on other network devices, since 8x less frags are mapped on transmit and unmapped on tx completion. Alexander Duyck mentioned a probable performance win on systems with IOMMU enabled. Its possible some SG enabled hardware cant cope with bigger fragments, but their ndo_start_xmit() should already handle this, splitting a fragment in sub fragments, since some arches have PAGE_SIZE=65536 Successfully tested on various ethernet devices. (ixgbe, igb, bnx2x, tg3, mellanox mlx4) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: Vijay Subramanian <subramanian.vijay@gmail.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-26ipv4: fix path MTU discovery with connection trackingPatrick McHardy1-1/+3
IPv4 conntrack defragments incoming packet at the PRE_ROUTING hook and (in case of forwarded packets) refragments them at POST_ROUTING independent of the IP_DF flag. Refragmentation uses the dst_mtu() of the local route without caring about the original fragment sizes, thereby breaking PMTUD. This patch fixes this by keeping track of the largest received fragment with IP_DF set and generates an ICMP fragmentation required error during refragmentation if that size exceeds the MTU. Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-21ipv4: fix ip header ident selection in __ip_make_skb()Eric Dumazet1-1/+1
Christian Casteyde reported a kmemcheck 32-bit read from uninitialized memory in __ip_select_ident(). It turns out that __ip_make_skb() called ip_select_ident() before properly initializing iph->daddr. This is a bug uncovered by commit 1d861aa4b3fb (inet: Minimize use of cached route inetpeer.) Addresses https://bugzilla.kernel.org/show_bug.cgi?id=46131 Reported-by: Christian Casteyde <casteyde.christian@free.fr> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-10ipv4: fix ip_send_skb()Eric Dumazet1-3/+2
ip_send_skb() can send orphaned skb, so we must pass the net pointer to avoid possible NULL dereference in error path. Bug added by commit 3a7c384ffd57 (ipv4: tcp: unicast_sock should not land outside of TCP stack) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-09ipv4: tcp: unicast_sock should not land outside of TCP stackEric Dumazet1-0/+1
commit be9f4a44e7d41cee (ipv4: tcp: remove per net tcp_sock) added a selinux regression, reported and bisected by John Stultz selinux_ip_postroute_compat() expect to find a valid sk->sk_security pointer, but this field is NULL for unicast_sock It turns out that unicast_sock are really temporary stuff to be able to reuse part of IP stack (ip_append_data()/ip_push_pending_frames()) Fact is that frames sent by ip_send_unicast_reply() should be orphaned to not fool LSM. Note IPv6 never had this problem, as tcp_v6_send_response() doesnt use a fake socket at all. I'll probably implement tcp_v4_send_response() to remove these unicast_sock in linux-3.7 Reported-by: John Stultz <johnstul@us.ibm.com> Bisected-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Eric Paris <eparis@parisplace.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-06ip: fix error handling in ip_finish_output2()Vasiliy Kulikov1-1/+1
__neigh_create() returns either a pointer to struct neighbour or PTR_ERR(). But the caller expects it to return either a pointer or NULL. Replace the NULL check with IS_ERR() check. The bug was introduced in a263b3093641fb1ec377582c90986a7fd0625184 ("ipv4: Make neigh lookups directly in output packet path."). Signed-off-by: Vasily Kulikov <segoon@openwall.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22Merge branch 'kill_rtcache'David S. Miller1-1/+1
The ipv4 routing cache is non-deterministic, performance wise, and is subject to reasonably easy to launch denial of service attacks. The routing cache works great for well behaved traffic, and the world was a much friendlier place when the tradeoffs that led to the routing cache's design were considered. What it boils down to is that the performance of the routing cache is a product of the traffic patterns seen by a system rather than being a product of the contents of the routing tables. The former of which is controllable by external entitites. Even for "well behaved" legitimate traffic, high volume sites can see hit rates in the routing cache of only ~%10. The general flow of this patch series is that first the routing cache is removed. We build a completely new rtable entry every lookup request. Next we make some simplifications due to the fact that removing the routing cache causes several members of struct rtable to become no longer necessary. Then we need to make some amends such that we can legally cache pre-constructed routes in the FIB nexthops. Firstly, we need to invalidate routes which are hit with nexthop exceptions. Secondly we have to change the semantics of rt->rt_gateway such that zero means that the destination is on-link and non-zero otherwise. Now that the preparations are ready, we start caching precomputed routes in the FIB nexthops. Output and input routes need different kinds of care when determining if we can legally do such caching or not. The details are in the commit log messages for those changes. The patch series then winds down with some more struct rtable simplifications and other tidy ups that remove unnecessary overhead. On a SPARC-T3 output route lookups are ~876 cycles. Input route lookups are ~1169 cycles with rpfilter disabled, and about ~1468 cycles with rpfilter enabled. These measurements were taken with the kbench_mod test module in the net_test_tools GIT tree: git://git.kernel.org/pub/scm/linux/kernel/git/davem/net_test_tools.git That GIT tree also includes a udpflood tester tool and stresses route lookups on packet output. For example, on the same SPARC-T3 system we can run: time ./udpflood -l 10000000 10.2.2.11 with routing cache: real 1m21.955s user 0m6.530s sys 1m15.390s without routing cache: real 1m31.678s user 0m6.520s sys 1m25.140s Performance undoubtedly can easily be improved further. For example fib_table_lookup() performs a lot of excessive computations with all the masking and shifting, some of it conditionalized to deal with edge cases. Also, Eric's no-ref optimization for input route lookups can be re-instated for the FIB nexthop caching code path. I would be really pleased if someone would work on that. In fact anyone suitable motivated can just fire up perf on the loading of the test net_test_tools benchmark kernel module. I spend much of my time going: bash# perf record insmod ./kbench_mod.ko dst=172.30.42.22 src=74.128.0.1 iif=2 bash# perf report Thanks to helpful feedback from Joe Perches, Eric Dumazet, Ben Hutchings, and others. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22ipv4: tcp: set unicast_sock uc_ttl to -1Eric Dumazet1-1/+2
Set unicast_sock uc_ttl to -1 so that we select the right ttl, instead of sending packets with a 0 ttl. Bug added in commit be9f4a44e7d4 (ipv4: tcp: remove per net tcp_sock) Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: Adjust semantics of rt->rt_gateway.David S. Miller1-1/+1
In order to allow prefixed routes, we have to adjust how rt_gateway is set and interpreted. The new interpretation is: 1) rt_gateway == 0, destination is on-link, nexthop is iph->daddr 2) rt_gateway != 0, destination requires a nexthop gateway Abstract the fetching of the proper nexthop value using a new inline helper, rt_nexthop(), as suggested by Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com>
2012-07-19ipv4: tcp: remove per net tcp_sockEric Dumazet1-18/+32
tcp_v4_send_reset() and tcp_v4_send_ack() use a single socket per network namespace. This leads to bad behavior on multiqueue NICS, because many cpus contend for the socket lock and once socket lock is acquired, extra false sharing on various socket fields slow down the operations. To better resist to attacks, we use a percpu socket. Each cpu can run without contention, using appropriate memory (local node) Additional features : 1) We also mirror the queue_mapping of the incoming skb, so that answers use the same queue if possible. 2) Setting SOCK_USE_WRITE_QUEUE socket flag speedup sock_wfree() 3) We now limit the number of in-flight RST/ACK [1] packets per cpu, instead of per namespace, and we honor the sysctl_wmem_default limit dynamically. (Prior to this patch, sysctl_wmem_default value was copied at boot time, so any further change would not affect tcp_sock limit) [1] These packets are only generated when no socket was matched for the incoming packet. Reported-by: Bill Sommerfeld <wsommerfeld@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05net: Do delayed neigh confirmation.David S. Miller1-1/+1
When a dst_confirm() happens, mark the confirmation as pending in the dst. Then on the next packet out, when we have the neigh in-hand, do the update. This removes the dependency in dst_confirm() of dst's having an attached neigh. While we're here, remove the explicit 'dst' NULL check, all except 2 or 3 call sites ensure it's not NULL. So just fix those cases up. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05ipv4: Make neigh lookups directly in output packet path.David S. Miller1-4/+8
Do not use the dst cached neigh, we'll be getting rid of that. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-28ipv4: Show that ip_send_reply() is purely unicast routine.David S. Miller1-4/+5
Rename it to ip_send_unicast_reply() and add explicit 'saddr' argument. This removed one of the few users of rt->rt_spec_dst. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-12net-next: add dev_loopback_xmit() to avoid duplicate codeMichel Machado1-15/+2
Add dev_loopback_xmit() in order to deduplicate functions ip_dev_loopback_xmit() (in net/ipv4/ip_output.c) and ip6_dev_loopback_xmit() (in net/ipv6/ip6_output.c). I was about to reinvent the wheel when I noticed that ip_dev_loopback_xmit() and ip6_dev_loopback_xmit() do exactly what I need and are not IP-only functions, but they were not available to reuse elsewhere. ip6_dev_loopback_xmit() does not have line "skb_dst_force(skb);", but I understand that this is harmless, and should be in dev_loopback_xmit(). Signed-off-by: Michel Machado <michel@digirati.com.br> CC: "David S. Miller" <davem@davemloft.net> CC: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> CC: James Morris <jmorris@namei.org> CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> CC: Patrick McHardy <kaber@trash.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jpirko@redhat.com> CC: "Michał Mirosław" <mirq-linux@rere.qmqm.pl> CC: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-04net: use consume_skb() in place of kfree_skb()Eric Dumazet1-2/+2
Remove some dropwatch/drop_monitor false positives. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-15net: Convert net_ratelimit uses to net_<level>_ratelimitedJoe Perches1-2/+2
Standardize the net core ratelimited logging functions. Coalesce formats, align arguments. Change a printk then vprintk sequence to use printf extension %pV. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-28Remove all #inclusions of asm/system.hDavid Howells1-1/+0
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2011-12-05net: Rename dst_get_neighbour{, _raw} to dst_get_neighbour_noref{, _raw}.David Miller1-1/+1
To reflect the fact that a refrence is not obtained to the resulting neighbour entry. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Roland Dreier <roland@purestorage.com>
2011-12-01ipv4: use a 64bit load/store in output pathEric Dumazet1-4/+17
gcc compiler is smart enough to use a single load/store if we memcpy(dptr, sptr, 8) on x86_64, regardless of CONFIG_CC_OPTIMIZE_FOR_SIZE In IP header, daddr immediately follows saddr, this wont change in the future. We only need to make sure our flowi4 (saddr,daddr) fields wont break the rule. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAITEric Dumazet1-3/+3
There is a long standing bug in linux tcp stack, about ACK messages sent on behalf of TIME_WAIT sockets. In the IP header of the ACK message, we choose to reflect TOS field of incoming message, and this might break some setups. Example of things that were broken : - Routing using TOS as a selector - Firewalls - Trafic classification / shaping We now remember in timewait structure the inet tos field and use it in ACK generation, and route lookup. Notes : - We still reflect incoming TOS in RST messages. - We could extend MuraliRaja Muniraju patch to report TOS value in netlink messages for TIME_WAIT sockets. - A patch is needed for IPv6 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-19net: add skb frag size accessorsEric Dumazet1-3/+3
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>
2011-08-24net: ipv4: convert to SKB frag APIsIan Campbell1-3/+4
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>
2011-08-07ipv4: use dst with ref during bcast/mcast loopbackJulian Anastasov1-0/+1
Make sure skb dst has reference when moving to another context. Currently, I don't see protocols that can hit it when sending broadcasts/multicasts to loopback using noref dsts, so it is just a precaution. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-03net: fix NULL dereferences in check_peer_redir()Eric Dumazet1-2/+8
Gergely Kalman reported crashes in check_peer_redir(). It appears commit f39925dbde778 (ipv4: Cache learned redirect information in inetpeer.) added a race, leading to possible NULL ptr dereference. Since we can now change dst neighbour, we should make sure a reader can safely use a neighbour. Add RCU protection to dst neighbour, and make sure check_peer_redir() can be called safely by different cpus in parallel. As neighbours are already freed after one RCU grace period, this patch should not add typical RCU penalty (cache cold effects) Many thanks to Gergely for providing a pretty report pointing to the bug. Reported-by: Gergely Kalman <synapse@hippy.csoma.elte.hu> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21ipv4: Constrain UFO fragment sizes to multiples of 8 bytesBill Sommerfeld1-3/+3
Because the ip fragment offset field counts 8-byte chunks, ip fragments other than the last must contain a multiple of 8 bytes of payload. ip_ufo_append_data wasn't respecting this constraint and, depending on the MTU and ip option sizes, could create malformed non-final fragments. Google-Bug-Id: 5009328 Signed-off-by: Bill Sommerfeld <wsommerfeld@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-17net: Abstract dst->neighbour accesses behind helpers.David S. Miller1-1/+1
dst_{get,set}_neighbour() Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16net: Create and use new helper, neigh_output().David S. Miller1-7/+3
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16ipv4: Use calculated 'neigh' instead of re-evaluating dst->neighbourDavid S. Miller1-1/+1
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-14net: Embed hh_cache inside of struct neighbour.David S. Miller1-5/+9
Now that there is a one-to-one correspondance between neighbour and hh_cache entries, we no longer need: 1) dynamic allocation 2) attachment to dst->hh 3) refcounting Initialization of the hh_cache entry is indicated by hh_len being non-zero, and such initialization is always done with the neighbour's lock held as a writer. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-05Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-11/+8
2011-07-01ipv4: Don't use ufo handling on later transformed packetsSteffen Klassert1-1/+1
We might call ip_ufo_append_data() for packets that will be IPsec transformed later. This function should be used just for real udp packets. So we check for rt->dst.header_len which is only nonzero on IPsec handling and call ip_ufo_append_data() just if rt->dst.header_len is zero. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-27ipv4: Fix IPsec slowpath fragmentation problemSteffen Klassert1-5/+5
ip_append_data() builds packets based on the mtu from dst_mtu(rt->dst.path). On IPsec the effective mtu is lower because we need to add the protocol headers and trailers later when we do the IPsec transformations. So after the IPsec transformations the packet might be too big, which leads to a slowpath fragmentation then. This patch fixes this by building the packets based on the lower IPsec mtu from dst_mtu(&rt->dst) and adapts the exthdr handling to this. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-27ipv4: Fix packet size calculation in __ip_append_dataSteffen Klassert1-5/+2
Git commit 59104f06 (ip: take care of last fragment in ip_append_data) added a check to see if we exceed the mtu when we add trailer_len. However, the mtu is already subtracted by the trailer length when the xfrm transfomation bundles are set up. So IPsec packets with mtu size get fragmented, or if the DF bit is set the packets will not be send even though they match the mtu perfectly fine. This patch actually reverts commit 59104f06. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21ip: introduce ip_is_fragment helper inline functionPaul Gortmaker1-1/+1
There are enough instances of this: iph->frag_off & htons(IP_MF | IP_OFFSET) that a helper function is probably warranted. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-09ipv4: Fix packet size calculation for raw IPsec packets in __ip_append_dataSteffen Klassert1-3/+3
We assume that transhdrlen is positive on the first fragment which is wrong for raw packets. So we don't add exthdrlen to the packet size for raw packets. This leads to a reallocation on IPsec because we have not enough headroom on the skb to place the IPsec headers. This patch fixes this by adding exthdrlen to the packet size whenever the send queue of the socket is empty. This issue was introduced with git commit 1470ddf7 (inet: Remove explicit write references to sk/inet in ip_append_data) Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-13ipv4: Always call ip_options_build() after rest of IP header is filled in.David S. Miller1-4/+5
This will allow ip_options_build() to reliably look at the values of iph->{daddr,saddr} Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-10ipv4: Pass explicit daddr arg to ip_send_reply().David S. Miller1-4/+3
This eliminates an access to rt->rt_src. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08ipv4: Pass flow key down into ip_append_*().David S. Miller1-8/+10
This way rt->rt_dst accesses are unnecessary. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08ipv4: Pass flow keys down into datagram packet building engine.David S. Miller1-20/+19
This way ip_output.c no longer needs rt->rt_{src,dst}. We already have these keys sitting, ready and waiting, on the stack or in a socket structure. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08ipv4: Don't use rt->rt_{src,dst} in ip_queue_xmit().David S. Miller1-4/+4
Now we can pick it out of the provided flow key. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08inet: Pass flowi to ->queue_xmit().David S. Miller1-2/+2
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>
2011-05-08ipv4: Use cork flow in ip_queue_xmit()David S. Miller1-2/+3
All invokers of ip_queue_xmit() must make certain that the socket is locked. All of SCTP, TCP, DCCP, and L2TP now make sure this is the case. Therefore we can use the cork flow during output route lookup in ip_queue_xmit() when the socket route check fails. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-06ipv4: Initialize cork->opt using NULL not 0.David S. Miller1-1/+1
Noticed by Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-06ipv4: Initialize on-stack cork more efficiently.David S. Miller1-1/+4
ip_setup_cork() explicitly initializes every member of inet_cork except flags, addr, and opt. So we can simply set those three members to zero instead of using a memset() via an empty struct assignment. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
2011-05-06inet: Decrease overhead of on-stack inet_cork.David S. Miller1-10/+12
When we fast path datagram sends to avoid locking by putting the inet_cork on the stack we use up lots of space that isn't necessary. This is because inet_cork contains a "struct flowi" which isn't used in these code paths. Split inet_cork to two parts, "inet_cork" and "inet_cork_full". Only the latter of which has the "struct flowi" and is what is stored in inet_sock. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
2011-05-04ipv4: In ip_build_and_send_pkt() use 'saddr' and 'daddr' args passed in.David S. Miller1-2/+2
Instead of rt->rt_{dst,src} The only tricky part is source route option handling. If the source route option is enabled we can't just use plain 'daddr', we have to use opt->opt.faddr. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-03ipv4: Make caller provide on-stack flow key to ip_route_output_ports().David S. Miller1-1/+2
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28inet: add RCU protection to inet->optEric Dumazet1-23/+21
We lack proper synchronization to manipulate inet->opt ip_options Problem is ip_make_skb() calls ip_setup_cork() and ip_setup_cork() possibly makes a copy of ipc->opt (struct ip_options), without any protection against another thread manipulating inet->opt. Another thread can change inet->opt pointer and free old one under us. Use RCU to protect inet->opt (changed to inet->inet_opt). Instead of handling atomic refcounts, just copy ip_options when necessary, to avoid cache line dirtying. We cant insert an rcu_head in struct ip_options since its included in skb->cb[], so this patch is large because I had to introduce a new ip_options_rcu structure. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>