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2011-10-25net: Unlock sock before calling sk_free()Thomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-13net: more accurate skb truesizeEric Dumazet
skb truesize currently accounts for sk_buff struct and part of skb head. kmalloc() roundings are also ignored. Considering that skb_shared_info is larger than sk_buff, its time to take it into account for better memory accounting. This patch introduces SKB_TRUESIZE(X) macro to centralize various assumptions into a single place. At skb alloc phase, we put skb_shared_info struct at the exact end of skb head, to allow a better use of memory (lowering number of reallocations), since kmalloc() gives us power-of-two memory blocks. Unless SLUB/SLUB debug is active, both skb->head and skb_shared_info are aligned to cache lines, as before. Note: This patch might trigger performance regressions because of misconfigured protocol stacks, hitting per socket or global memory limits that were previously not reached. But its a necessary step for a more accurate memory accounting. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Andi Kleen <ak@linux.intel.com> CC: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-07net: use sock_valbool_flag to set/clear SOCK_RXQ_OVFLJohannes Berg
There's no point in open-coding sock_valbool_flag(). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-24net: convert core to skb paged frag APIsIan Campbell
Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-02rcu: convert uses of rcu_assign_pointer(x, NULL) to RCU_INIT_POINTERStephen Hemminger
When assigning a NULL value to an RCU protected pointer, no barrier is needed. The rcu_assign_pointer, used to handle that but will soon change to not handle the special case. Convert all rcu_assign_pointer of NULL value. //smpl @@ expression P; @@ - rcu_assign_pointer(P, NULL) + RCU_INIT_POINTER(P, NULL) // </smpl> Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-08Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem
2011-07-05NFC: add NFC socket familyAloisio Almeida Jr
Signed-off-by: Lauro Ramos Venancio <lauro.venancio@openbossa.org> Signed-off-by: Aloisio Almeida Jr <aloisio.almeida@openbossa.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-06-21core: add tracepoints for queueing skb to rcvbufSatoru Moriya
This patch adds 2 tracepoints to get a status of a socket receive queue and related parameter. One tracepoint is added to sock_queue_rcv_skb. It records rcvbuf size and its usage. The other tracepoint is added to __sk_mem_schedule and it records limitations of memory for sockets and current usage. By using these tracepoints we're able to know detailed reason why kernel drop the packet. Signed-off-by: Satoru Moriya <satoru.moriya@hds.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-01-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (46 commits) hwrng: via_rng - Fix memory scribbling on some CPUs crypto: padlock - Move padlock.h into include/crypto hwrng: via_rng - Fix asm constraints crypto: n2 - use __devexit not __exit in n2_unregister_algs crypto: mark crypto workqueues CPU_INTENSIVE crypto: mv_cesa - dont return PTR_ERR() of wrong pointer crypto: ripemd - Set module author and update email address crypto: omap-sham - backlog handling fix crypto: gf128mul - Remove experimental tag crypto: af_alg - fix af_alg memory_allocated data type crypto: aesni-intel - Fixed build with binutils 2.16 crypto: af_alg - Make sure sk_security is initialized on accept()ed sockets net: Add missing lockdep class names for af_alg include: Install linux/if_alg.h for user-space crypto API crypto: omap-aes - checkpatch --file warning fixes crypto: omap-aes - initialize aes module once per request crypto: omap-aes - unnecessary code removed crypto: omap-aes - error handling implementation improved crypto: omap-aes - redundant locking is removed crypto: omap-aes - DMA initialization fixes for OMAP off mode ...
2011-01-06net: add POLLPRI to sock_def_readable()Eric Dumazet
Leonardo Chiquitto found poll() could block forever on tcp sockets and Urgent data was received, if the event flag only contains POLLPRI. He did a bisection and found commit 4938d7e0233 (poll: avoid extra wakeups in select/poll) was the source of the problem. Problem is TCP sockets use standard sock_def_readable() function for their sk_data_ready() handler, and sock_def_readable() doesnt signal POLLPRI. Only TCP is affected by the problem. Adding POLLPRI to the list of flags might trigger unnecessary schedules, but URGENT handling is such a seldom used feature this seems a good compromise. Thanks a lot to Leonardo for providing the bisection result and a test program as well. Reference : http://www.spinics.net/lists/netdev/msg151793.html Reported-and-bisected-by: Leonardo Chiquitto <leonardo.lists@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-17Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/bnx2x/bnx2x.h drivers/net/wireless/iwlwifi/iwl-1000.c drivers/net/wireless/iwlwifi/iwl-6000.c drivers/net/wireless/iwlwifi/iwl-core.h drivers/vhost/vhost.c
2010-12-16net: fix nulls list corruptions in sk_prot_allocOctavian Purdila
Special care is taken inside sk_port_alloc to avoid overwriting skc_node/skc_nulls_node. We should also avoid overwriting skc_bind_node/skc_portaddr_node. The patch fixes the following crash: BUG: unable to handle kernel paging request at fffffffffffffff0 IP: [<ffffffff812ec6dd>] udp4_lib_lookup2+0xad/0x370 [<ffffffff812ecc22>] __udp4_lib_lookup+0x282/0x360 [<ffffffff812ed63e>] __udp4_lib_rcv+0x31e/0x700 [<ffffffff812bba45>] ? ip_local_deliver_finish+0x65/0x190 [<ffffffff812bbbf8>] ? ip_local_deliver+0x88/0xa0 [<ffffffff812eda35>] udp_rcv+0x15/0x20 [<ffffffff812bba45>] ip_local_deliver_finish+0x65/0x190 [<ffffffff812bbbf8>] ip_local_deliver+0x88/0xa0 [<ffffffff812bb2cd>] ip_rcv_finish+0x32d/0x6f0 [<ffffffff8128c14c>] ? netif_receive_skb+0x99c/0x11c0 [<ffffffff812bb94b>] ip_rcv+0x2bb/0x350 [<ffffffff8128c14c>] netif_receive_skb+0x99c/0x11c0 Signed-off-by: Leonard Crestez <lcrestez@ixiacom.com> Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-09net: optimize INET input path furtherEric Dumazet
Followup of commit b178bb3dfc30 (net: reorder struct sock fields) Optimize INET input path a bit further, by : 1) moving sk_refcnt close to sk_lock. This reduces number of dirtied cache lines by one on 64bit arches (and 64 bytes cache line size). 2) moving inet_daddr & inet_rcv_saddr at the beginning of sk (same cache line than hash / family / bound_dev_if / nulls_node) This reduces number of accessed cache lines in lookups by one, and dont increase size of inet and timewait socks. inet and tw sockets now share same place-holder for these fields. Before patch : offsetof(struct sock, sk_refcnt) = 0x10 offsetof(struct sock, sk_lock) = 0x40 offsetof(struct sock, sk_receive_queue) = 0x60 offsetof(struct inet_sock, inet_daddr) = 0x270 offsetof(struct inet_sock, inet_rcv_saddr) = 0x274 After patch : offsetof(struct sock, sk_refcnt) = 0x44 offsetof(struct sock, sk_lock) = 0x48 offsetof(struct sock, sk_receive_queue) = 0x68 offsetof(struct inet_sock, inet_daddr) = 0x0 offsetof(struct inet_sock, inet_rcv_saddr) = 0x4 compute_score() (udp or tcp) now use a single cache line per ignored item, instead of two. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08net: Add missing lockdep class names for af_algMiloslav Trmač
Signed-off-by: Miloslav Trmač <mitr@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-11-10net: avoid limits overflowEric Dumazet
Robin Holt tried to boot a 16TB machine and found some limits were reached : sysctl_tcp_mem[2], sysctl_udp_mem[2] We can switch infrastructure to use long "instead" of "int", now atomic_long_t primitives are available for free. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Reported-by: Robin Holt <holt@sgi.com> Reviewed-by: Robin Holt <holt@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-25net: add __rcu annotation to sk_filterEric Dumazet
Add __rcu annotation to : (struct sock)->sk_filter And use appropriate rcu primitives to reduce sparse warnings if CONFIG_SPARSE_RCU_POINTER=y Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1699 commits) bnx2/bnx2x: Unsupported Ethtool operations should return -EINVAL. vlan: Calling vlan_hwaccel_do_receive() is always valid. tproxy: use the interface primary IP address as a default value for --on-ip tproxy: added IPv6 support to the socket match cxgb3: function namespace cleanup tproxy: added IPv6 support to the TPROXY target tproxy: added IPv6 socket lookup function to nf_tproxy_core be2net: Changes to use only priority codes allowed by f/w tproxy: allow non-local binds of IPv6 sockets if IP_TRANSPARENT is enabled tproxy: added tproxy sockopt interface in the IPV6 layer tproxy: added udp6_lib_lookup function tproxy: added const specifiers to udp lookup functions tproxy: split off ipv6 defragmentation to a separate module l2tp: small cleanup nf_nat: restrict ICMP translation for embedded header can: mcp251x: fix generation of error frames can: mcp251x: fix endless loop in interrupt handler if CANINTF_MERRF is set can-raw: add msg_flags to distinguish local traffic 9p: client code cleanup rds: make local functions/variables static ... Fix up conflicts in net/core/dev.c, drivers/net/pcmcia/smc91c92_cs.c and drivers/net/wireless/ath/ath9k/debug.c as per David
2010-10-07net: suppress RCU lockdep false positive in sock_update_classidPaul E. McKenney
> =================================================== > [ INFO: suspicious rcu_dereference_check() usage. ] > --------------------------------------------------- > include/linux/cgroup.h:542 invoked rcu_dereference_check() without protection! > > other info that might help us debug this: > > > rcu_scheduler_active = 1, debug_locks = 0 > 1 lock held by swapper/1: > #0: (net_mutex){+.+.+.}, at: [<ffffffff813e9010>] > register_pernet_subsys+0x1f/0x47 > > stack backtrace: > Pid: 1, comm: swapper Not tainted 2.6.35.4-28.fc14.x86_64 #1 > Call Trace: > [<ffffffff8107bd3a>] lockdep_rcu_dereference+0xaa/0xb3 > [<ffffffff813e04b9>] sock_update_classid+0x7c/0xa2 > [<ffffffff813e054a>] sk_alloc+0x6b/0x77 > [<ffffffff8140b281>] __netlink_create+0x37/0xab > [<ffffffff813f941c>] ? rtnetlink_rcv+0x0/0x2d > [<ffffffff8140cee1>] netlink_kernel_create+0x74/0x19d > [<ffffffff8149c3ca>] ? __mutex_lock_common+0x339/0x35b > [<ffffffff813f7e9c>] rtnetlink_net_init+0x2e/0x48 > [<ffffffff813e8d7a>] ops_init+0xe9/0xff > [<ffffffff813e8f0d>] register_pernet_operations+0xab/0x130 > [<ffffffff813e901f>] register_pernet_subsys+0x2e/0x47 > [<ffffffff81db7bca>] rtnetlink_init+0x53/0x102 > [<ffffffff81db835c>] netlink_proto_init+0x126/0x143 > [<ffffffff81db8236>] ? netlink_proto_init+0x0/0x143 > [<ffffffff810021b8>] do_one_initcall+0x72/0x186 > [<ffffffff81d78ebc>] kernel_init+0x23b/0x2c9 > [<ffffffff8100aae4>] kernel_thread_helper+0x4/0x10 > [<ffffffff8149e2d0>] ? restore_args+0x0/0x30 > [<ffffffff81d78c81>] ? kernel_init+0x0/0x2c9 > [<ffffffff8100aae0>] ? kernel_thread_helper+0x0/0x10 The sock_update_classid() function calls task_cls_classid(current), but the calling task cannot go away, so there is no danger of the associated structures disappearing. Insert an RCU read-side critical section to suppress the false positive. Reported-by: Subrata Modak <subrata@linux.vnet.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-09-27Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/qlcnic/qlcnic_init.c net/ipv4/ip_output.c
2010-09-24net: fix a lockdep splatEric Dumazet
We have for each socket : One spinlock (sk_slock.slock) One rwlock (sk_callback_lock) Possible scenarios are : (A) (this is used in net/sunrpc/xprtsock.c) read_lock(&sk->sk_callback_lock) (without blocking BH) <BH> spin_lock(&sk->sk_slock.slock); ... read_lock(&sk->sk_callback_lock); ... (B) write_lock_bh(&sk->sk_callback_lock) stuff write_unlock_bh(&sk->sk_callback_lock) (C) spin_lock_bh(&sk->sk_slock) ... write_lock_bh(&sk->sk_callback_lock) stuff write_unlock_bh(&sk->sk_callback_lock) spin_unlock_bh(&sk->sk_slock) This (C) case conflicts with (A) : CPU1 [A] CPU2 [C] read_lock(callback_lock) <BH> spin_lock_bh(slock) <wait to spin_lock(slock)> <wait to write_lock_bh(callback_lock)> We have one problematic (C) use case in inet_csk_listen_stop() : local_bh_disable(); bh_lock_sock(child); // spin_lock_bh(&sk->sk_slock) WARN_ON(sock_owned_by_user(child)); ... sock_orphan(child); // write_lock_bh(&sk->sk_callback_lock) lockdep is not happy with this, as reported by Tetsuo Handa It seems only way to deal with this is to use read_lock_bh(callbacklock) everywhere. Thanks to Jarek for pointing a bug in my first attempt and suggesting this solution. Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Jarek Poplawski <jarkao2@gmail.com> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09net/core: add lock context change annotations in net/core/sock.cNamhyung Kim
__lock_sock() and __release_sock() releases and regrabs lock but were missing proper annotations. Add it. This removes following warning from sparse. (Currently __lock_sock() does not emit any warning about it but I think it is better to add also.) net/core/sock.c:1580:17: warning: context imbalance in '__release_sock' - unexpected unlock Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-19net: this_cpu_xxx conversionsEric Dumazet
Use modern this_cpu_xxx() api, saving few bytes on x86 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-12net: sock_free() optimizationsEric Dumazet
Avoid two extra instructions in sock_free(), to reload skb->truesize and skb->sk Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-16net: Export cred_to_ucred to modules.David S. Miller
AF_UNIX references this, and can be built as a module, so... Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-16af_unix: Allow SO_PEERCRED to work across namespaces.Eric W. Biederman
Use struct pid and struct cred to store the peer credentials on struct sock. This gives enough information to convert the peer credential information to a value relative to whatever namespace the socket is in at the time. This removes nasty surprises when using SO_PEERCRED on socket connetions where the processes on either side are in different pid and user namespaces. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-16sock: Introduce cred_to_ucredEric W. Biederman
To keep the coming code clear and to allow both the sock code and the scm code to share the logic introduce a fuction to translate from struct cred to struct ucred. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-07net-caif: Added missing lock validator constantsAlex Lorca
CAIF is using "xxx-AF_MAX" strings for the lock validator. It should use its own strings. Signed-off-by: Alex Lorca <alex.lorca@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-27net: fix lock_sock_bh/unlock_sock_bhEric Dumazet
This new sock lock primitive was introduced to speedup some user context socket manipulation. But it is unsafe to protect two threads, one using regular lock_sock/release_sock, one using lock_sock_bh/unlock_sock_bh This patch changes lock_sock_bh to be careful against 'owned' state. If owned is found to be set, we must take the slow path. lock_sock_bh() now returns a boolean to say if the slow path was taken, and this boolean is used at unlock_sock_bh time to call the appropriate unlock function. After this change, BH are either disabled or enabled during the lock_sock_bh/unlock_sock_bh protected section. This might be misleading, so we rename these functions to lock_sock_fast()/unlock_sock_fast(). Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-24tun: Update classid on packet injectionHerbert Xu
This patch makes tun update its socket classid every time we inject a packet into the network stack. This is so that any updates made by the admin to the process writing packets to tun is effected. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-24cls_cgroup: Store classid in struct sockHerbert Xu
Up until now cls_cgroup has relied on fetching the classid out of the current executing thread. This runs into trouble when a packet processing is delayed in which case it may execute out of another thread's context. Furthermore, even when a packet is not delayed we may fail to classify it if soft IRQs have been disabled, because this scenario is indistinguishable from one where a packet unrelated to the current thread is processed by a real soft IRQ. In fact, the current semantics is inherently broken, as a single skb may be constructed out of the writes of two different tasks. A different manifestation of this problem is when the TCP stack transmits in response of an incoming ACK. This is currently unclassified. As we already have a concept of packet ownership for accounting purposes in the skb->sk pointer, this is a natural place to store the classid in a persistent manner. This patch adds the cls_cgroup classid in struct sock, filling up an existing hole on 64-bit :) The value is set at socket creation time. So all sockets created via socket(2) automatically gains the ID of the thread creating it. Whenever another process touches the socket by either reading or writing to it, we will change the socket classid to that of the process if it has a valid (non-zero) classid. For sockets created on inbound connections through accept(2), we inherit the classid of the original listening socket through sk_clone, possibly preceding the actual accept(2) call. In order to minimise risks, I have not made this the authoritative classid. For now it is only used as a backup when we execute with soft IRQs disabled. Once we're completely happy with its semantics we can use it as the sole classid. Footnote: I have rearranged the error path on cls_group module creation. If we didn't do this, then there is a window where someone could create a tc rule using cls_group before the cgroup subsystem has been registered. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-17net: add a noref bit on skb dstEric Dumazet
Use low order bit of skb->_skb_dst to tell dst is not refcounted. Change _skb_dst to _skb_refdst to make sure all uses are catched. skb_dst() returns the dst, regardless of noref bit set or not, but with a lockdep check to make sure a noref dst is not given if current user is not rcu protected. New skb_dst_set_noref() helper to set an notrefcounted dst on a skb. (with lockdep check) skb_dst_drop() drops a reference only if skb dst was refcounted. skb_dst_force() helper is used to force a refcount on dst, when skb is queued and not anymore RCU protected. Use skb_dst_force() in __sk_add_backlog(), __dev_xmit_skb() if !IFF_XMIT_DST_RELEASE or skb enqueued on qdisc queue, in sock_queue_rcv_skb(), in __nf_queue(). Use skb_dst_force() in dev_requeue_skb(). Note: dst_use_noref() still dirties dst, we might transform it later to do one dirtying per jiffies. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-16net: Introduce sk_route_nocapsEric Dumazet
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>
2010-05-01net: sock_def_readable() and friends RCU conversionEric Dumazet
sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we need two atomic operations (and associated dirtying) per incoming packet. RCU conversion is pretty much needed : 1) Add a new structure, called "struct socket_wq" to hold all fields that will need rcu_read_lock() protection (currently: a wait_queue_head_t and a struct fasync_struct pointer). [Future patch will add a list anchor for wakeup coalescing] 2) Attach one of such structure to each "struct socket" created in sock_alloc_inode(). 3) Respect RCU grace period when freeing a "struct socket_wq" 4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct socket_wq" 5) Change sk_sleep() function to use new sk->sk_wq instead of sk->sk_sleep 6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside a rcu_read_lock() section. 7) Change all sk_has_sleeper() callers to : - Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock) - Use wq_has_sleeper() to eventually wakeup tasks. - Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock) 8) sock_wake_async() is modified to use rcu protection as well. 9) Exceptions : macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq" instead of dynamically allocated ones. They dont need rcu freeing. Some cleanups or followups are probably needed, (possible sk_callback_lock conversion to a spinlock for example...). Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-27net: sk_add_backlog() take rmem_alloc into accountEric Dumazet
Current socket backlog limit is not enough to really stop DDOS attacks, because user thread spend many time to process a full backlog each round, and user might crazy spin on socket lock. We should add backlog size and receive_queue size (aka rmem_alloc) to pace writers, and let user run without being slow down too much. Introduce a sk_rcvqueues_full() helper, to avoid taking socket lock in stress situations. Under huge stress from a multiqueue/RPS enabled NIC, a single flow udp receiver can now process ~200.000 pps (instead of ~100 pps before the patch) on a 8 core machine. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-20net: sk_sleep() helperEric Dumazet
Define a new function to return the waitqueue of a "struct sock". static inline wait_queue_head_t *sk_sleep(struct sock *sk) { return sk->sk_sleep; } Change all read occurrences of sk_sleep by a call to this function. Needed for a future RCU conversion. sk_sleep wont be a field directly available. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-13net: sk_dst_cache RCUificationEric Dumazet
With latest CONFIG_PROVE_RCU stuff, I felt more comfortable to make this work. sk->sk_dst_cache is currently protected by a rwlock (sk_dst_lock) This rwlock is readlocked for a very small amount of time, and dst entries are already freed after RCU grace period. This calls for RCU again :) This patch converts sk_dst_lock to a spinlock, and use RCU for readers. __sk_dst_get() is supposed to be called with rcu_read_lock() or if socket locked by user, so use appropriate rcu_dereference_check() condition (rcu_read_lock_held() || sock_owned_by_user(sk)) This patch avoids two atomic ops per tx packet on UDP connected sockets, for example, and permits sk_dst_lock to be much less dirtied. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-07sock.c: potential null dereferenceDan Carpenter
We test that "prot->rsk_prot" is non-null right before we dereference it on this line. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-05net: backlog functions renameZhu Yi
sk_add_backlog -> __sk_add_backlog sk_add_backlog_limited -> sk_add_backlog Signed-off-by: Zhu Yi <yi.zhu@intel.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-05net: add limit for socket backlogZhu Yi
We got system OOM while running some UDP netperf testing on the loopback device. The case is multiple senders sent stream UDP packets to a single receiver via loopback on local host. Of course, the receiver is not able to handle all the packets in time. But we surprisingly found that these packets were not discarded due to the receiver's sk->sk_rcvbuf limit. Instead, they are kept queuing to sk->sk_backlog and finally ate up all the memory. We believe this is a secure hole that a none privileged user can crash the system. The root cause for this problem is, when the receiver is doing __release_sock() (i.e. after userspace recv, kernel udp_recvmsg -> skb_free_datagram_locked -> release_sock), it moves skbs from backlog to sk_receive_queue with the softirq enabled. In the above case, multiple busy senders will almost make it an endless loop. The skbs in the backlog end up eat all the system memory. The issue is not only for UDP. Any protocols using socket backlog is potentially affected. The patch adds limit for socket backlog so that the backlog size cannot be expanded endlessly. Reported-by: Alex Shi <alex.shi@intel.com> Cc: David Miller <davem@davemloft.net> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi> Cc: Patrick McHardy <kaber@trash.net> Cc: Vlad Yasevich <vladislav.yasevich@hp.com> Cc: Sridhar Samudrala <sri@us.ibm.com> Cc: Jon Maloy <jon.maloy@ericsson.com> Cc: Allan Stephens <allan.stephens@windriver.com> Cc: Andrew Hendry <andrew.hendry@gmail.com> Signed-off-by: Zhu Yi <yi.zhu@intel.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-28Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller
Conflicts: drivers/firmware/iscsi_ibft.c
2010-02-25net: Add checking to rcu_dereference() primitivesPaul E. McKenney
Update rcu_dereference() primitives to use new lockdep-based checking. The rcu_dereference() in __in6_dev_get() may be protected either by rcu_read_lock() or RTNL, per Eric Dumazet. The rcu_dereference() in __sk_free() is protected by the fact that it is never reached if an update could change it. Check for this by using rcu_dereference_check() to verify that the struct sock's ->sk_wmem_alloc counter is zero. Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-5-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-17net: use kasprintf() for socket cache namesAlexey Dobriyan
kasprintf() makes code smaller. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-17net: spread __net_init, __net_exitAlexey Dobriyan
__net_init/__net_exit are apparently not going away, so use them to full extent. In some cases __net_init was removed, because it was called from __net_exit code. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-15net/core/sock.c: quiet sparse noiseH Hartley Sweeten
In sock_getsockopt the symbol 'lv' is declared as an unsigned int type, probably due to sizeof returning a size_t which is really an unsigned int. This produces a sparse warning for SO_PEERNAME due to the sock->ops->getname() call: warning: incorrect type in argument 3 (different signedness) expected int *sockaddr_len got unsigned int *<noident> Quiet the warning by changing the type of 'lv' to an int. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-08tcp: update the netstamp_needed counter when cloning socketsOctavian Purdila
This fixes a netstamp_needed accounting issue when the listen socket has SO_TIMESTAMP set: s = socket(AF_INET, SOCK_STREAM, 0); setsockopt(s, SOL_SOCKET, SO_TIMESTAMP, 1); -> netstamp_needed = 1 bind(s, ...); listen(s, ...); s2 = accept(s, ...); -> netstamp_needed = 1 close(s2); -> netstamp_needed = 0 close(s); -> netstamp_needed = -1 Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-05net: Fix build warning in sock_bindtodevice().David S. Miller
net/core/sock.c: In function 'sock_setsockopt': net/core/sock.c:396: warning: 'index' may be used uninitialized in this function net/core/sock.c:396: note: 'index' was declared here GCC can't see that all paths initialize index, so just set it to the default (0) and eliminate the specific code block that handles the null device name string. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-05net: sock_bindtodevice() RCU-ificationEric Dumazet
Avoid dev_hold()/dev_put() in sock_bindtodevice() Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-20net: Fix for dst_negative_adviceKrishna Kumar
dst_negative_advice() should check for changed dst and reset sk_tx_queue_mapping accordingly. Pass sock to the callers of dst_negative_advice. (sk_reset_txq is defined just for use by dst_negative_advice. The only way I could find to get around this is to move dst_negative_() from dst.h to dst.c, include sock.h in dst.c, etc) Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-20net: Introduce sk_tx_queue_mappingKrishna Kumar
Introduce sk_tx_queue_mapping; and functions that set, test and get this value. Reset sk_tx_queue_mapping to -1 whenever the dst cache is set/reset, and in socket alloc. Setting txq to -1 and using valid txq=<0 to n-1> allows the tx path to use the value of sk_tx_queue_mapping directly instead of subtracting 1 on every tx. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>