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2009-09-30net: Make setsockopt() optlen be unsigned.David S. Miller
This provides safety against negative optlen at the type level instead of depending upon (sometimes non-trivial) checks against this sprinkled all over the the place, in each and every implementation. Based upon work done by Arjan van de Ven and feedback from Linus Torvalds. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-22mm: replace various uses of num_physpages by totalram_pagesJan Beulich
Sizing of memory allocations shouldn't depend on the number of physical pages found in a system, as that generally includes (perhaps a huge amount of) non-RAM pages. The amount of what actually is usable as storage should instead be used as a basis here. Some of the calculations (i.e. those not intending to use high memory) should likely even use (totalram_pages - totalhigh_pages). Signed-off-by: Jan Beulich <jbeulich@novell.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Dave Airlie <airlied@linux.ie> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: "David S. Miller" <davem@davemloft.net> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-12Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: arch/microblaze/include/asm/socket.h
2009-08-09Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller
2009-08-05net: mark read-only arrays as constJan Engelhardt
String literals are constant, and usually, we can also tag the array of pointers const too, moving it to the .rodata section. Signed-off-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-05dccp: missing destroy of percpu counter variable while unload moduleWei Yongjun
percpu counter dccp_orphan_count is init in dccp_init() by percpu_counter_init() while dccp module is loaded, but the destroy of it is missing while dccp module is unloaded. We can get the kernel WARNING about this. Reproduct by the following commands: $ modprobe dccp $ rmmod dccp $ modprobe dccp WARNING: at lib/list_debug.c:26 __list_add+0x27/0x5c() Hardware name: VMware Virtual Platform list_add corruption. next->prev should be prev (c080c0c4), but was (null). (next =ca7188cc). Modules linked in: dccp(+) nfsd lockd nfs_acl auth_rpcgss exportfs sunrpc Pid: 1956, comm: modprobe Not tainted 2.6.31-rc5 #55 Call Trace: [<c042f8fa>] warn_slowpath_common+0x6a/0x81 [<c053a6cb>] ? __list_add+0x27/0x5c [<c042f94f>] warn_slowpath_fmt+0x29/0x2c [<c053a6cb>] __list_add+0x27/0x5c [<c053c9b3>] __percpu_counter_init+0x4d/0x5d [<ca9c90c7>] dccp_init+0x19/0x2ed [dccp] [<c0401141>] do_one_initcall+0x4f/0x111 [<ca9c90ae>] ? dccp_init+0x0/0x2ed [dccp] [<c06971b5>] ? notifier_call_chain+0x26/0x48 [<c0444943>] ? __blocking_notifier_call_chain+0x45/0x51 [<c04516f7>] sys_init_module+0xac/0x1bd [<c04028e4>] sysenter_do_call+0x12/0x22 Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-29net-dccp: suppress warning about large allocations from DCCPMel Gorman
The DCCP protocol tries to allocate some large hash tables during initialisation using the largest size possible. This can be larger than what the page allocator can provide so it prints a warning. However, the caller is able to handle the situation so this patch suppresses the warning. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-09net: adding memory barrier to the poll and receive callbacksJiri Olsa
Adding memory barrier after the poll_wait function, paired with receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper to wrap the memory barrier. Without the memory barrier, following race can happen. The race fires, when following code paths meet, and the tp->rcv_nxt and __add_wait_queue updates stay in CPU caches. CPU1 CPU2 sys_select receive packet ... ... __add_wait_queue update tp->rcv_nxt ... ... tp->rcv_nxt check sock_def_readable ... { schedule ... if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep) ... } If there was no cache the code would work ok, since the wait_queue and rcv_nxt are opposit to each other. Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already passed the tp->rcv_nxt check and sleeps, or will get the new value for tp->rcv_nxt and will return with new data mask. In both cases the process (CPU1) is being added to the wait queue, so the waitqueue_active (CPU2) call cannot miss and will wake up CPU1. The bad case is when the __add_wait_queue changes done by CPU1 stay in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 will then endup calling schedule and sleep forever if there are no more data on the socket. Calls to poll_wait in following modules were ommited: net/bluetooth/af_bluetooth.c net/irda/af_irda.c net/irda/irnet/irnet_ppp.c net/mac80211/rc80211_pid_debugfs.c net/phonet/socket.c net/rds/af_rds.c net/rfkill/core.c net/sunrpc/cache.c net/sunrpc/rpc_pipe.c net/tipc/socket.c Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21dccp: Implement both feature-local and feature-remote Sequence Window featureGerrit Renker
This adds full support for local/remote Sequence Window feature, from which the * sequence-number-validity (W) and * acknowledgment-number-validity (W') windows derive as specified in RFC 4340, 7.5.3. Specifically, the following is contained in this patch: * integrated new socket fields into dccp_sk; * updated the update_gsr/gss routines with regard to these fields; * updated handler code: the Sequence Window feature is located at the TX side, so the local feature is meant if the handler-rx flag is false; * the initialisation of `rcv_wnd' in reqsk is removed, since - rcv_wnd is not used by the code anywhere; - sequence number checks are not done in the LISTEN state (cf. 7.5.3); - dccp_check_req checks the Ack number validity more rigorously; * the `struct dccp_minisock' became empty and is now removed. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-04dccp: Lockless integration of CCID congestion-control pluginsGerrit Renker
Based on Arnaldo's earlier patch, this patch integrates the standardised CCID congestion control plugins (CCID-2 and CCID-3) of DCCP with dccp.ko: * enables a faster connection path by eliminating the need to always go through the CCID registration lock; * updates the implementation to use only a single array whose size equals the number of configured CCIDs instead of the maximum (256); * since the CCIDs are now fixed array elements, synchronization is no longer needed, simplifying use and implementation. CCID-2 is suggested as minimum for a basic DCCP implementation (RFC 4340, 10); CCID-3 is a standards-track CCID supported by RFC 4342 and RFC 5348. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> 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>
2008-12-08dccp ccid-2: Phase out the use of boolean Ack Vector sysctlGerrit Renker
This removes the use of the sysctl and the minisock variable for the Send Ack Vector feature, as it now is handled fully dynamically via feature negotiation (i.e. when CCID-2 is enabled, Ack Vectors are automatically enabled as per RFC 4341, 4.). Using a sysctl in parallel to this implementation would open the door to crashes, since much of the code relies on tests of the boolean minisock / sysctl variable. Thus, this patch replaces all tests of type if (dccp_msk(sk)->dccpms_send_ack_vector) /* ... */ with if (dp->dccps_hc_rx_ackvec != NULL) /* ... */ The dccps_hc_rx_ackvec is allocated by the dccp_hdlr_ackvec() when feature negotiation concluded that Ack Vectors are to be used on the half-connection. Otherwise, it is NULL (due to dccp_init_sock/dccp_create_openreq_child), so that the test is a valid one. The activation handler for Ack Vectors is called as soon as the feature negotiation has concluded at the * server when the Ack marking the transition RESPOND => OPEN arrives; * client after it has sent its ACK, marking the transition REQUEST => PARTOPEN. Adding the sequence number of the Response packet to the Ack Vector has been removed, since (a) connection establishment implies that the Response has been received; (b) the CCIDs only look at packets received in the (PART)OPEN state, i.e. this entry will always be ignored; (c) it can not be used for anything useful - to detect loss for instance, only packets received after the loss can serve as pseudo-dupacks. There was a FIXME to change the error code when dccp_ackvec_add() fails. I removed this after finding out that: * the check whether ackno < ISN is already made earlier, * this Response is likely the 1st packet with an Ackno that the client gets, * so when dccp_ackvec_add() fails, the reason is likely not a packet error. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-08dccp: Integration of dynamic feature activation - part 1 (socket setup)Gerrit Renker
This first patch out of three replaces the hardcoded default settings with initialisation code for the dynamic feature negotiation. The patch also ensures that the client feature-negotiation queue is flushed only when entering the OPEN state. Since confirmed Change options are removed as soon as they are confirmed (in the DCCP-Response), this ensures that Confirm options are retransmitted. Note on retransmitting Confirm options: --------------------------------------- Implementation experience showed that it is necessary to retransmit Confirm options. Thanks to Leandro Melo de Sales who reported a bug in an earlier revision of the patch set, resulting from not retransmitting these options. As long as the client is in PARTOPEN, it needs to retransmit the Confirm options for the Change options received on the DCCP-Response from the server. Otherwise, if the packet containing the Confirm options gets dropped in the network, the connection aborts due to undefined feature negotiation state. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-25net: 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>
2008-11-23dccp: API to query the current TX/RX CCIDGerrit Renker
This provides function to query the current TX/RX CCID dynamically, without reliance on the minisock value, using dynamic information available in the currently loaded CCID module. This query function is then used to (a) provide the getsockopt part for getting/setting CCIDs via sockopts; (b) replace the current test for "which CCID is in use" in probe.c. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-23dccp: Set per-connection CCIDs via socket optionsGerrit Renker
With this patch, TX/RX CCIDs can now be changed on a per-connection basis, which overrides the defaults set by the global sysctl variables for TX/RX CCIDs. To make full use of this facility, the remaining patches of this patch set are needed, which track dependencies and activate negotiated feature values. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20net: listening_hash get a spinlock per bucketEric Dumazet
This patch prepares RCU migration of listening_hash table for TCP/DCCP protocols. listening_hash table being small (32 slots per protocol), we add a spinlock for each slot, instead of a single rwlock for whole table. This should reduce hold time of readers, and writers concurrency. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16dccp: Tidy up setsockopt callsGerrit Renker
This splits the setsockopt calls into two groups, depending on whether an integer argument (val) is required and whether routines being called do their own locking. Some options (such as setting the CCID) use u8 rather than int, so that for these the test with regard to integer-sizeof can not be used. The second switch-case statement now only has those statements which need locking and which make use of `val'. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Reviewed-by: Eugene Teo <eugeneteo@kernel.sg> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16dccp: Feature negotiation for minimum-checksum-coverageGerrit Renker
This provides feature negotiation for server minimum checksum coverage which so far has been missing. Since sender/receiver coverage values range only from 0...15, their type has also been reduced in size from u16 to u4. Feature-negotiation options are now generated for both sender and receiver coverage, i.e. when the peer has `forgotten' to enable partial coverage then feature negotiation will automatically enable (negotiate) the partial coverage value for this connection. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16dccp: Deprecate old setsockopt frameworkGerrit Renker
The previous setsockopt interface, which passed socket options via struct dccp_so_feat, is complicated/difficult to use. Continuing to support it leads to ugly code since the old approach did not distinguish between NN and SP values. This patch removes the old setsockopt interface and replaces it with two new functions to register NN/SP values for feature negotiation. These are essentially wrappers around the internal __feat_register functions, with checking added to avoid * wrong usage (type); * changing values while the connection is in progress. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> 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>
2008-11-12dccp: Resolve dependencies of features on choice of CCIDGerrit Renker
This provides a missing link in the code chain, as several features implicitly depend and/or rely on the choice of CCID. Most notably, this is the Send Ack Vector feature, but also Ack Ratio and Send Loss Event Rate (also taken care of). For Send Ack Vector, the situation is as follows: * since CCID2 mandates the use of Ack Vectors, there is no point in allowing endpoints which use CCID2 to disable Ack Vector features such a connection; * a peer with a TX CCID of CCID2 will always expect Ack Vectors, and a peer with a RX CCID of CCID2 must always send Ack Vectors (RFC 4341, sec. 4); * for all other CCIDs, the use of (Send) Ack Vector is optional and thus negotiable. However, this implies that the code negotiating the use of Ack Vectors also supports it (i.e. is able to supply and to either parse or ignore received Ack Vectors). Since this is not the case (CCID-3 has no Ack Vector support), the use of Ack Vectors is here disabled, with a comment in the source code. An analogous consideration arises for the Send Loss Event Rate feature, since the CCID-3 implementation does not support the loss interval options of RFC 4342. To make such use explicit, corresponding feature-negotiation options are inserted which signal the use of the loss event rate option, as it is used by the CCID3 code. Lastly, the values of the Ack Ratio feature are matched to the choice of CCID. The patch implements this as a function which is called after the user has made all other registrations for changing default values of features. The table is variable-length, the reserved (and hence for feature-negotiation invalid, confirmed by considering section 19.4 of RFC 4340) feature number `0' is used to mark the end of the table. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-12dccp: Query supported CCIDsGerrit Renker
This provides a data structure to record which CCIDs are locally supported and three accessor functions: - a test function for internal use which is used to validate CCID requests made by the user; - a copy function so that the list can be used for feature-negotiation; - documented getsockopt() support so that the user can query capabilities. The data structure is a table which is filled in at compile-time with the list of available CCIDs (which in turn depends on the Kconfig choices). Using the copy function for cloning the list of supported CCIDs is useful for feature negotiation, since the negotiation is now with the full list of available CCIDs (e.g. {2, 3}) instead of the default value {2}. This means negotiation will not fail if the peer requests to use CCID3 instead of CCID2. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-12dccp: Registration routines for changing feature valuesGerrit Renker
Two registration routines, for SP and NN features, are provided by this patch, replacing a previous routine which was used for both feature types. These are internal-only routines and therefore start with `__feat_register'. It further exports the known limits of Sequence Window and Ack Ratio as symbolic constants. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-04dccp: Cleanup routines for feature negotiationGerrit Renker
This inserts the required de-allocation routines for memory allocated by feature negotiation in the socket destructors, replacing dccp_feat_clean() in one instance. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-04dccp: Per-socket initialisation of feature negotiationGerrit Renker
This provides feature-negotiation initialisation for both DCCP sockets and DCCP request_sockets, to support feature negotiation during connection setup. It also resolves a FIXME regarding the congestion control initialisation. Thanks to Wei Yongjun for help with the IPv6 side of this patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-09This reverts "Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/dccp_exp"Gerrit Renker
as it accentally contained the wrong set of patches. These will be submitted separately. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp tfrc: Let dccp_tfrc_lib do the sampling workGerrit Renker
This migrates more TFRC-related code into the dccp_tfrc_lib: * sampling of the packet size `s' (which is only needed until the first loss interval is computed (ccid3_first_li)); * updating the byte-counter `bytes_recvd' in between sending feedbacks. The result is a better separation of CCID-3 specific and TFRC specific code, which aids future integration with ECN and e.g. CCID-4. Further changes: ---------------- * replaced magic number of 536 with equivalent constant TCP_MIN_RCVMSS; (this constant is also used when no estimate for `s' is available). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp qpolicy: Parameter checking of cmsg qpolicy parametersTomasz Grobelny
Ensure that cmsg->cmsg_type value is valid for qpolicy that is currently in use. Signed-off-by: Tomasz Grobelny <tomasz@grobelny.oswiecenia.net> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Policy-based packet dequeueing infrastructureTomasz Grobelny
This patch adds a generic infrastructure for policy-based dequeueing of TX packets and provides two policies: * a simple FIFO policy (which is the default) and * a priority based policy (set via socket options). Both policies honour the tx_qlen sysctl for the maximum size of the write queue (can be overridden via socket options). The priority policy uses skb->priority internally to assign an u32 priority identifier, using the same ranking as SO_PRIORITY. The skb->priority field is set to 0 when the packet leaves DCCP. The priority is supplied as ancillary data using cmsg(3), the patch also provides the requisite parsing routines. Signed-off-by: Tomasz Grobelny <tomasz@grobelny.oswiecenia.net> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Refine the wait-for-ccid mechanismGerrit Renker
This extends the existing wait-for-ccid routine so that it may be used with different types of CCID. It further addresses the problems listed below. The code looks if the write queue is non-empty and grants the TX CCID up to `timeout' jiffies to drain the queue. It will instead purge that queue if * the delay suggested by the CCID exceeds the time budget; * a socket error occurred while waiting for the CCID; * there is a signal pending (eg. annoyed user pressed Control-C); * the CCID does not support delays (we don't know how long it will take). D e t a i l s [can be removed] ------------------------------- DCCP's sending mechanism functions a bit like non-blocking I/O: dccp_sendmsg() will enqueue up to net.dccp.default.tx_qlen packets (default=5), without waiting for them to be released to the network. Rate-based CCIDs, such as CCID3/4, can impose sending delays of up to maximally 64 seconds (t_mbi in RFC 3448). Hence the write queue may still contain packets when the application closes. Since the write queue is congestion-controlled by the CCID, draining the queue is also under control of the CCID. There are several problems that needed to be addressed: 1) The queue-drain mechanism only works with rate-based CCIDs. If CCID2 for example has a full TX queue and becomes network-limited just as the application wants to close, then waiting for CCID2 to become unblocked could lead to an indefinite delay (i.e., application "hangs"). 2) Since each TX CCID in turn uses a feedback mechanism, there may be changes in its sending policy while the queue is being drained. This can lead to further delays during which the application will not be able to terminate. 3) The minimum wait time for CCID3/4 can be expected to be the queue length times the current inter-packet delay. For example if tx_qlen=100 and a delay of 15 ms is used for each packet, then the application would have to wait for a minimum of 1.5 seconds before being allowed to exit. 4) There is no way for the user/application to control this behaviour. It would be good to use the timeout argument of dccp_close() as an upper bound. Then the maximum time that an application is willing to wait for its CCIDs to can be set via the SO_LINGER option. These problems are addressed by giving the CCID a grace period of up to the `timeout' value. The wait-for-ccid function is, as before, used when the application (a) has read all the data in its receive buffer and (b) if SO_LINGER was set with a non-zero linger time, or (c) the socket is either in the OPEN (active close) or in the PASSIVE_CLOSEREQ state (client application closes after receiving CloseReq). In addition, there is a catch-all case by calling __skb_queue_purge() after waiting for the CCID. This is necessary since the write queue may still have data when (a) the host has been passively-closed, (b) abnormal termination (unread data, zero linger time), (c) wait-for-ccid could not finish within the given time limit. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp ccid-2: Use feature-negotiation to report Ack Ratio changesGerrit Renker
This uses the new feature-negotiation framework to signal Ack Ratio changes, as required by RFC 4341, sec. 6.1.2. This raises some problems for CCID-2 since it can at the moment not cope gracefully with Ack Ratio of e.g. 2. A FIXME has thus been added which reverts to the existing policy of bypassing the Ack Ratio sysctl. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Implement both feature-local and feature-remote Sequence Window featureGerrit Renker
This adds full support for local/remote Sequence Window feature, from which the * sequence-number-validity (W) and * acknowledgment-number-validity (W') windows derive as specified in RFC 4340, 7.5.3. Specifically, the following changes are introduced: * integrated new socket fields into dccp_sk; * updated the update_gsr/gss routines with regard to these fields; * updated handler code: the Sequence Window feature is located at the TX side, so the local feature is meant if the handler-rx flag is false; * the initialisation of `rcv_wnd' in reqsk is removed, since - rcv_wnd is not used by the code anywhere; - sequence number checks are not done in the LISTEN state (cf. 7.5.3); - dccp_check_req checks the Ack number validity more rigorously; * the `struct dccp_minisock' became empty and is now removed. Until the handshake completes with activating negotiated values, the local/remote Sequence-Window values are undefined and thus can not reliably be estimated. This issue is addressed in a separate patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp ccid-2: Phase out the use of boolean Ack Vector sysctlGerrit Renker
This removes the use of the sysctl and the minisock variable for the Send Ack Vector feature, which is now handled fully dynamically via feature negotiation; i.e. when CCID2 is enabled, Ack Vectors are automatically enabled (as per RFC 4341, 4.). Using a sysctl in parallel to this implementation would open the door to crashes, since much of the code relies on tests of the boolean minisock / sysctl variable. Thus, this patch replaces all tests of type if (dccp_msk(sk)->dccpms_send_ack_vector) /* ... */ with if (dp->dccps_hc_rx_ackvec != NULL) /* ... */ The dccps_hc_rx_ackvec is allocated by the dccp_hdlr_ackvec() when feature negotiation concluded that Ack Vectors are to be used on the half-connection. Otherwise, it is NULL (due to dccp_init_sock/dccp_create_openreq_child), so that the test is a valid one. The activation handler for Ack Vectors is called as soon as the feature negotiation has concluded at the * server when the Ack marking the transition RESPOND => OPEN arrives; * client after it has sent its ACK, marking the transition REQUEST => PARTOPEN. Adding the sequence number of the Response packet to the Ack Vector has been removed, since (a) connection establishment implies that the Response has been received; (b) the CCIDs only look at packets received in the (PART)OPEN state, i.e. this entry will always be ignored; (c) it can not be used for anything useful - to detect loss for instance, only packets received after the loss can serve as pseudo-dupacks. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Integration of dynamic feature activation - part 1 (socket setup)Gerrit Renker
This first patch out of three replaces the hardcoded default settings with initialisation code for the dynamic feature negotiation. Note on retransmitting Confirm options: --------------------------------------- This patch also defers flushing the client feature-negotiation queue, due to the following considerations. As long as the client is in PARTOPEN, it needs to retransmit the Confirm options for the Change options received on the DCCP-Response from the server. Otherwise, if the packet containing the Confirm options gets dropped in the network, the connection aborts due to undefined feature negotiation state. Thanks to Leandro Melo de Sales who reported a bug in an earlier revision of the patch set, resulting from not retransmitting the Confirm options. The patch now ensures that the client feature-negotiation queue is flushed only when entering the OPEN state. Since confirmed Change options are removed as soon as they are confirmed (in the DCCP-Response), this ensures that Confirm options are retransmitted. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: API to query the current TX/RX CCIDGerrit Renker
This provides function to query the current TX/RX CCID dynamically, without reliance on the minisock value, using dynamic information available in the currently loaded CCID module. This query function is then used to (a) provide the getsockopt part for getting/setting CCIDs via sockopts; (b) replace the current test for "which CCID is in use" in probe.c. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Set per-connection CCIDs via socket optionsGerrit Renker
With this patch, TX/RX CCIDs can now be changed on a per-connection basis, which overrides the defaults set by the global sysctl variables for TX/RX CCIDs. To make full use of this facility, the remaining patches of this patch set are needed, which track dependencies and activate negotiated feature values. Note on the maximum number of CCIDs that can be registered: ----------------------------------------------------------- The maximum number of CCIDs that can be registered on the socket is constrained by the space in a Confirm/Change feature negotiation option. The space in these in turn depends on the size of header options as defined in RFC 4340, 5.8. Since this is a recurring constant, it has been moved from ackvec.h into linux/dccp.h, clarifying its purpose. Relative to this size, the maximum number of CCID identifiers that can be present in a Confirm option (which always consumes 1 byte more than a Change option, cf. 6.1) is 2 bytes less than the maximum TLV size: one for the CCID-feature-type and one for the selected value. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Tidy up setsockopt callsGerrit Renker
This splits the setsockopt calls into two groups, depending on whether an integer argument (val) is required and whether routines being called do their own locking. Some options (such as setting the CCID) use u8 rather than int, so that for these the test with regard to integer-sizeof can not be used. The second switch-case statement now only has those statements which need locking and which make use of `val'. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Reviewed-by: Eugene Teo <eugeneteo@kernel.sg>
2008-09-04dccp: Feature negotiation for minimum-checksum-coverageGerrit Renker
This provides feature negotiation for server minimum checksum coverage which so far has been missing. Since sender/receiver coverage values range only from 0...15, their type has also been reduced in size from u16 to u4. Feature-negotiation options are now generated for both sender and receiver coverage, i.e. when the peer has `forgotten' to enable partial coverage then feature negotiation will automatically enable (negotiate) the partial coverage value for this connection. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Deprecate old setsockopt frameworkGerrit Renker
The previous setsockopt interface, which passed socket options via struct dccp_so_feat, is complicated/difficult to use. Continuing to support it leads to ugly code since the old approach did not distinguish between NN and SP values. This patch removes the old setsockopt interface and replaces it with two new functions to register NN/SP values for feature negotiation. These are essentially wrappers around the internal __feat_register functions, with checking added to avoid * wrong usage (type); * changing values while the connection is in progress. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Resolve dependencies of features on choice of CCIDGerrit Renker
This provides a missing link in the code chain, as several features implicitly depend and/or rely on the choice of CCID. Most notably, this is the Send Ack Vector feature, but also Ack Ratio and Send Loss Event Rate (also taken care of). For Send Ack Vector, the situation is as follows: * since CCID2 mandates the use of Ack Vectors, there is no point in allowing endpoints which use CCID2 to disable Ack Vector features such a connection; * a peer with a TX CCID of CCID2 will always expect Ack Vectors, and a peer with a RX CCID of CCID2 must always send Ack Vectors (RFC 4341, sec. 4); * for all other CCIDs, the use of (Send) Ack Vector is optional and thus negotiable. However, this implies that the code negotiating the use of Ack Vectors also supports it (i.e. is able to supply and to either parse or ignore received Ack Vectors). Since this is not the case (CCID-3 has no Ack Vector support), the use of Ack Vectors is here disabled, with a comment in the source code. An analogous consideration arises for the Send Loss Event Rate feature, since the CCID-3 implementation does not support the loss interval options of RFC 4342. To make such use explicit, corresponding feature-negotiation options are inserted which signal the use of the loss event rate option, as it is used by the CCID3 code. Lastly, the values of the Ack Ratio feature are matched to the choice of CCID. The patch implements this as a function which is called after the user has made all other registrations for changing default values of features. The table is variable-length, the reserved (and hence for feature-negotiation invalid, confirmed by considering section 19.4 of RFC 4340) feature number `0' is used to mark the end of the table. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Query supported CCIDsGerrit Renker
This provides a data structure to record which CCIDs are locally supported and three accessor functions: - a test function for internal use which is used to validate CCID requests made by the user; - a copy function so that the list can be used for feature-negotiation; - documented getsockopt() support so that the user can query capabilities. The data structure is a table which is filled in at compile-time with the list of available CCIDs (which in turn depends on the Kconfig choices). Using the copy function for cloning the list of supported CCIDs is useful for feature negotiation, since the negotiation is now with the full list of available CCIDs (e.g. {2, 3}) instead of the default value {2}. This means negotiation will not fail if the peer requests to use CCID3 instead of CCID2. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Registration routines for changing feature valuesGerrit Renker
Two registration routines, for SP and NN features, are provided by this patch, replacing a previous routine which was used for both feature types. These are internal-only routines and therefore start with `__feat_register'. It further exports the known limits of Sequence Window and Ack Ratio as symbolic constants. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Cleanup routines for feature negotiationGerrit Renker
This inserts the required de-allocation routines for memory allocated by feature negotiation in the socket destructors, replacing dccp_feat_clean() in one instance. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Per-socket initialisation of feature negotiationGerrit Renker
This provides feature-negotiation initialisation for both DCCP sockets and DCCP request_sockets, to support feature negotiation during connection setup. It also resolves a FIXME regarding the congestion control initialisation. Thanks to Wei Yongjun for help with the IPv6 side of this patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Toggle debug output without module unloadingGerrit Renker
This sets the sysfs permissions so that root can toggle the `debug' parameter available for nearly every DCCP module. This is useful since there are various module inter-dependencies. The debug flag can now be toggled at runtime using echo 1 > /sys/module/dccp/parameters/dccp_debug echo 1 > /sys/module/dccp_ccid2/parameters/ccid2_debug echo 1 > /sys/module/dccp_ccid3/parameters/ccid3_debug echo 1 > /sys/module/dccp_tfrc_lib/parameters/tfrc_debug The last is not very useful yet, since no code at the moment calls the tfrc_debug() macro. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04dccp: Empty the write queue when disconnectingGerrit Renker
dccp_disconnect() can be called due to several reasons: 1. when the connection setup failed (inet_stream_connect()); 2. when shutting down (inet_shutdown(), inet_csk_listen_stop()); 3. when aborting the connection (dccp_close() with 0 linger time). In case (1) the write queue is empty. This patch empties the write queue, if in case (2) or (3) it was not yet empty. This avoids triggering the write-queue BUG_TRAP in sk_stream_kill_queues() later on. It also seems natural to do: when breaking an association, to delete all packets that were originally intended for the soon-disconnected end (compare with call to tcp_write_queue_purge in tcp_disconnect()). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-08-13dccp: change L/R must have at least one byte in the dccpsf_val fieldArnaldo Carvalho de Melo
Thanks to Eugene Teo for reporting this problem. Signed-off-by: Eugene Teo <eugenete@kernel.sg> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> 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>
2008-06-14net: change proto destroy method to return voidBrian Haley
Change struct proto destroy function pointer to return void. Noticed by Al Viro. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>