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2016-02-06tipc: hold subscriber->lock for tipc_nametbl_subscribe()Parthasarathy Bhuvaragan
Until now, while creating a subscription the subscriber lock protects only the subscribers subscription list and not the nametable. The call to tipc_nametbl_subscribe() is outside the lock. However, at subscription timeout and cancel both the subscribers subscription list and the nametable are protected by the subscriber lock. This asymmetric locking mechanism leads to the following problem: In a SMP system, the timer can be fire on another core before the create request is complete. When the timer thread calls tipc_nametbl_unsubscribe() before create thread calls tipc_nametbl_subscribe(), we get a nullptr exception. This can be simulated by creating subscription with timeout=0 and sometimes the timeout occurs before the create request is complete. The following is the oops: [57.569661] BUG: unable to handle kernel NULL pointer dereference at (null) [57.577498] IP: [<ffffffffa02135aa>] tipc_nametbl_unsubscribe+0x8a/0x120 [tipc] [57.584820] PGD 0 [57.586834] Oops: 0002 [#1] SMP [57.685506] CPU: 14 PID: 10077 Comm: kworker/u40:1 Tainted: P OENX 3.12.48-52.27.1. 9688.1.PTF-default #1 [57.703637] Workqueue: tipc_rcv tipc_recv_work [tipc] [57.708697] task: ffff88064c7f00c0 ti: ffff880629ef4000 task.ti: ffff880629ef4000 [57.716181] RIP: 0010:[<ffffffffa02135aa>] [<ffffffffa02135aa>] tipc_nametbl_unsubscribe+0x8a/ 0x120 [tipc] [...] [57.812327] Call Trace: [57.814806] [<ffffffffa0211c77>] tipc_subscrp_delete+0x37/0x90 [tipc] [57.821357] [<ffffffffa0211e2f>] tipc_subscrp_timeout+0x3f/0x70 [tipc] [57.827982] [<ffffffff810618c1>] call_timer_fn+0x31/0x100 [57.833490] [<ffffffff81062709>] run_timer_softirq+0x1f9/0x2b0 [57.839414] [<ffffffff8105a795>] __do_softirq+0xe5/0x230 [57.844827] [<ffffffff81520d1c>] call_softirq+0x1c/0x30 [57.850150] [<ffffffff81004665>] do_softirq+0x55/0x90 [57.855285] [<ffffffff8105aa35>] irq_exit+0x95/0xa0 [57.860290] [<ffffffff815215b5>] smp_apic_timer_interrupt+0x45/0x60 [57.866644] [<ffffffff8152005d>] apic_timer_interrupt+0x6d/0x80 [57.872686] [<ffffffffa02121c5>] tipc_subscrb_rcv_cb+0x2a5/0x3f0 [tipc] [57.879425] [<ffffffffa021c65f>] tipc_receive_from_sock+0x9f/0x100 [tipc] [57.886324] [<ffffffffa021c826>] tipc_recv_work+0x26/0x60 [tipc] [57.892463] [<ffffffff8106fb22>] process_one_work+0x172/0x420 [57.898309] [<ffffffff8107079a>] worker_thread+0x11a/0x3c0 [57.903871] [<ffffffff81077114>] kthread+0xb4/0xc0 [57.908751] [<ffffffff8151f318>] ret_from_fork+0x58/0x90 In this commit, we do the following at subscription creation: 1. set the subscription's subscriber pointer before performing tipc_nametbl_subscribe(), as this value is required further in the call chain ex: by tipc_subscrp_send_event(). 2. move tipc_nametbl_subscribe() under the scope of subscriber lock Acked-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: fix connection abort when receiving invalid cancel requestParthasarathy Bhuvaragan
Until now, the subscribers endianness for a subscription create/cancel request is determined as: swap = !(s->filter & (TIPC_SUB_PORTS | TIPC_SUB_SERVICE)) The checks are performed only for port/service subscriptions. The swap calculation is incorrect if the filter in the subscription cancellation request is set to TIPC_SUB_CANCEL (it's a malformed cancel request, as the corresponding subscription create filter is missing). Thus, the check if the request is for cancellation fails and the request is treated as a subscription create request. The subscription creation fails as the request is illegal, which terminates this connection. In this commit we determine the endianness by including TIPC_SUB_CANCEL, which will set swap correctly and the request is processed as a cancellation request. Acked-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: fix connection abort during subscription cancellationParthasarathy Bhuvaragan
In 'commit 7fe8097cef5f ("tipc: fix nullpointer bug when subscribing to events")', we terminate the connection if the subscription creation fails. In the same commit, the subscription creation result was based on the value of subscription pointer (set in the function) instead of the return code. Unfortunately, the same function also handles subscription cancellation request. For a subscription cancellation request, the subscription pointer cannot be set. Thus the connection is terminated during cancellation request. In this commit, we move the subcription cancel check outside of tipc_subscrp_create(). Hence, - tipc_subscrp_create() will create a subscripton - tipc_subscrb_rcv_cb() will subscribe or cancel a subscription. Fixes: 'commit 7fe8097cef5f ("tipc: fix nullpointer bug when subscribing to events")' Acked-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: introduce tipc_subscrb_subscribe() routineParthasarathy Bhuvaragan
In this commit, we split tipc_subscrp_create() into two: 1. tipc_subscrp_create() creates a subscription 2. A new function tipc_subscrp_subscribe() adds the subscription to the subscriber subscription list, activates the subscription timer and subscribes to the nametable updates. In future commits, the purpose of tipc_subscrb_rcv_cb() will be to either subscribe or cancel a subscription. There is no functional change in this commit. Acked-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: remove struct tipc_name_seq from struct tipc_subscriptionParthasarathy Bhuvaragan
Until now, struct tipc_subscriber has duplicate fields for type, upper and lower (as member of struct tipc_name_seq) at: 1. as member seq in struct tipc_subscription 2. as member seq in struct tipc_subscr, which is contained in struct tipc_event The former structure contains the type, upper and lower values in network byte order and the later contains the intact copy of the request. The struct tipc_subscription contains a field swap to determine if request needs network byte order conversion. Thus by using swap, we can convert the request when required instead of duplicating it. In this commit, 1. we remove the references to these elements as members of struct tipc_subscription and replace them with elements from struct tipc_subscr. 2. provide new functions to convert the user request into network byte order. Acked-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: remove filter and timeout elements from struct tipc_subscriptionParthasarathy Bhuvaragan
Until now, struct tipc_subscription has duplicate timeout and filter attributes present: 1. directly as members of struct tipc_subscription 2. in struct tipc_subscr, which is contained in struct tipc_event In this commit, we remove the references to these elements as members of struct tipc_subscription and replace them with elements from struct tipc_subscr. Acked-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: remove incorrect check for subscription timeout valueParthasarathy Bhuvaragan
Until now, during subscription creation we set sub->timeout by converting the timeout request value in milliseconds to jiffies. This is followed by setting the timeout value in the timer if sub->timeout != TIPC_WAIT_FOREVER. For a subscription create request with a timeout value of TIPC_WAIT_FOREVER, msecs_to_jiffies(TIPC_WAIT_FOREVER) returns MAX_JIFFY_OFFSET (0xfffffffe). This is not equal to TIPC_WAIT_FOREVER (0xffffffff). In this commit, we remove this check. Acked-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: fix link priority propagationRichard Alpe
Currently link priority changes isn't handled for active links. In this patch we resolve this by changing our priority if the peer passes a valid priority in a state message. Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06tipc: fix link attribute propagation bugRichard Alpe
Changing certain link attributes (link tolerance and link priority) from the TIPC management tool is supposed to automatically take effect at both endpoints of the affected link. Currently the media address is not instantiated for the link and is used uninstantiated when crafting protocol messages designated for the peer endpoint. This means that changing a link property currently results in the property being changed on the local machine but the protocol message designated for the peer gets lost. Resulting in property discrepancy between the endpoints. In this patch we resolve this by using the media address from the link entry and using the bearer transmit function to send it. Hence, we can now eliminate the redundant function tipc_link_prot_xmit() and the redundant field tipc_link::media_addr. Fixes: 2af5ae372a4b (tipc: clean up unused code and structures) Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Reported-by: Jason Hu <huzhijiang@gmail.com> Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-29tipc: fix connection abort during subscription cancelParthasarathy Bhuvaragan
In 'commit 7fe8097cef5f ("tipc: fix nullpointer bug when subscribing to events")', we terminate the connection if the subscription creation fails. In the same commit, the subscription creation result was based on the value of the subscription pointer (set in the function) instead of the return code. Unfortunately, the same function tipc_subscrp_create() handles subscription cancel request. For a subscription cancellation request, the subscription pointer cannot be set. Thus if a subscriber has several subscriptions and cancels any of them, the connection is terminated. In this commit, we terminate the connection based on the return value of tipc_subscrp_create(). Fixes: commit 7fe8097cef5f ("tipc: fix nullpointer bug when subscribing to events") Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-26ip_tunnel: Move stats update to iptunnel_xmit()Pravin B Shelar
By moving stats update into iptunnel_xmit(), we can simplify iptunnel_xmit() usage. With this change there is no need to call another function (iptunnel_xmit_stats()) to update stats in tunnel xmit code path. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/renesas/ravb_main.c kernel/bpf/syscall.c net/ipv4/ipmr.c All three conflicts were cases of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-03tipc: fix node reference count bugJon Paul Maloy
Commit 5405ff6e15f40f2f ("tipc: convert node lock to rwlock") introduced a bug to the node reference counter handling. When a message is successfully sent in the function tipc_node_xmit(), we return directly after releasing the node lock, instead of continuing and decrementing the node reference counter as we should do. This commit fixes this bug. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-30net: Generalise wq_has_sleeper helperHerbert Xu
The memory barrier in the helper wq_has_sleeper is needed by just about every user of waitqueue_active. This patch generalises it by making it take a wait_queue_head_t directly. The existing helper is renamed to skwq_has_sleeper. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-24tipc: fix error handling of expanding buffer headroomYing Xue
Coverity says: *** CID 1338065: Error handling issues (CHECKED_RETURN) /net/tipc/udp_media.c: 162 in tipc_udp_send_msg() 156 struct udp_media_addr *dst = (struct udp_media_addr *)&dest->value; 157 struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value; 158 struct sk_buff *clone; 159 struct rtable *rt; 160 161 if (skb_headroom(skb) < UDP_MIN_HEADROOM) >>> CID 1338065: Error handling issues (CHECKED_RETURN) >>> Calling "pskb_expand_head" without checking return value (as is done elsewhere 51 out of 56 times). 162 pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC); 163 164 clone = skb_clone(skb, GFP_ATOMIC); 165 skb_set_inner_protocol(clone, htons(ETH_P_TIPC)); 166 ub = rcu_dereference_rtnl(b->media_ptr); 167 if (!ub) { When expanding buffer headroom over udp tunnel with pskb_expand_head(), it's unfortunate that we don't check its return value. As a result, if the function returns an error code due to the lack of memory, it may cause unpredictable consequence as we unconditionally consider that it's always successful. Fixes: e53567948f82 ("tipc: conditionally expand buffer headroom over udp tunnel") Reported-by: <scan-admin@coverity.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-24tipc: avoid packets leaking on socket receive queueYing Xue
Even if we drain receive queue thoroughly in tipc_release() after tipc socket is removed from rhashtable, it is possible that some packets are in flight because some CPU runs receiver and did rhashtable lookup before we removed socket. They will achieve receive queue, but nobody delete them at all. To avoid this leak, we register a private socket destructor to purge receive queue, meaning releasing packets pending on receive queue will be delayed until the last reference of tipc socket will be released. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: correct settings of broadcast link stateJon Paul Maloy
Since commit 5266698661401afc5e ("tipc: let broadcast packet reception use new link receive function") the broadcast send link state was meant to always be set to LINK_ESTABLISHED, since we don't need this link to follow the regular link FSM rules. It was also the intention that this state anyway shouldn't impact the run-time working state of the link, since the latter in reality is controlled by the number of registered peers. We have now discovered that this assumption is not quite correct. If the broadcast link is reset because of too many retransmissions, its state will inadvertently go to LINK_RESETTING, and never go back to LINK_ESTABLISHED, because the LINK_FAILURE event was not anticipated. This will work well once, but if it happens a second time, the reset on a link in LINK_RESETTING has has no effect, and neither the broadcast link nor the unicast links will go down as they should. Furthermore, it is confusing that the management tool shows that this link is in UP state when that obviously isn't the case. We now ensure that this state strictly follows the true working state of the link. The state is set to LINK_ESTABLISHED when the number of peers is non-zero, and to LINK_RESET otherwise. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: eliminate remnants of hungarian notationJon Paul Maloy
The number of variables with Hungarian notation (l_ptr, n_ptr etc.) has been significantly reduced over the last couple of years. We now root out the last traces of this practice. There are no functional changes in this commit. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: narrow down interface towards struct tipc_linkJon Paul Maloy
We move the definition of struct tipc_link from link.h to link.c in order to minimize its exposure to the rest of the code. When needed, we define new functions to make it possible for external entities to access and set data in the link. Apart from the above, there are no functional changes. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: narrow down exposure of struct tipc_nodeJon Paul Maloy
In our effort to have less code and include dependencies between entities such as node, link and bearer, we try to narrow down the exposed interface towards the node as much as possible. In this commit, we move the definition of struct tipc_node, along with many of its associated function declarations, from node.h to node.c. We also move some function definitions from link.c and name_distr.c to node.c, since they access fields in struct tipc_node that should not be externally visible. The moved functions are renamed according to new location, and made static whenever possible. There are no functional changes in this commit. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: convert node lock to rwlockJon Paul Maloy
According to the node FSM a node in state SELF_UP_PEER_UP cannot change state inside a lock context, except when a TUNNEL_PROTOCOL (SYNCH or FAILOVER) packet arrives. However, the node's individual links may still change state. Since each link now is protected by its own spinlock, we finally have the conditions in place to convert the node spinlock to an rwlock_t. If the node state and arriving packet type are rigth, we can let the link directly receive the packet under protection of its own spinlock and the node lock in read mode. In all other cases we use the node lock in write mode. This enables full concurrent execution between parallel links during steady-state traffic situations, i.e., 99+ % of the time. This commit implements this change. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: introduce per-link spinlockJon Paul Maloy
As a preparation to allow parallel links to work more independently from each other we introduce a per-link spinlock, to be stored in the struct nodes's link entry area. Since the node lock still is a regular spinlock there is no increase in parallellism at this stage. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: reduce code dependency between binding table and node layerJon Paul Maloy
The file name_distr.c currently contains three functions, named_cluster_distribute(), tipc_publ_subcscribe() and tipc_publ_unsubscribe() that all directly access fields in struct tipc_node. We want to eliminate such dependencies, so we move those functions to the file node.c and rename them to tipc_node_broadcast(), tipc_node_subscribe() and tipc_node_unsubscribe() respectively. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: small cleanup of function tipc_node_check_state()Jon Paul Maloy
The function tipc_node_check_state() contains the core logics for handling link synchronization and failover. For this reason, it is important to keep it as comprehensible as possible. In this commit, we make three small cleanups. 1) If the node is in state SELF_DOWN_PEER_LEAVING and the received packet confirms that the peer has lost contact, there will be no further action in this function. To make this clearer, we return from the function directly after the state change. 2) Since commit 0f8b8e28fb3241f9fd ("tipc: eliminate risk of stalled link synchronization") only the logically first TUNNEL_PROTO/SYNCH packet can alter the link state and set the synch point, independently of arrival order. Hence, there is not any longer any need to adjust the synch value in case such packets arrive in disorder. We remove this adjustment. 3) It is the intention that any message arriving on any of the links may trig a check for and possible termination of a node SYNCH state. A redundant and unnoticed check for tipc_link_is_synching() obviously beats this purpose, with the effect that only packets arriving on the synching link may currently end the synch state. We remove this check. This change will further shorten the synchronization period between parallel links. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-20tipc: move linearization of buffers to generic codeJon Paul Maloy
In commit 5cbb28a4bf65c7e4 ("tipc: linearize arriving NAME_DISTR and LINK_PROTO buffers") we added linearization of NAME_DISTRIBUTOR, LINK_PROTOCOL/RESET and LINK_PROTOCOL/ACTIVATE to the function tipc_udp_recv(). The location of the change was selected in order to make the commit easily appliable to 'net' and 'stable'. We now move this linearization to where it should be done, in the functions tipc_named_rcv() and tipc_link_proto_rcv() respectively. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Minor overlapping changes in net/ipv4/ipmr.c, in 'net' we were fixing the "BH-ness" of the counter bumps whilst in 'net-next' the functions were modified to take an explicit 'net' parameter. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-01tipc: linearize arriving NAME_DISTR and LINK_PROTO buffersJon Paul Maloy
Testing of the new UDP bearer has revealed that reception of NAME_DISTRIBUTOR, LINK_PROTOCOL/RESET and LINK_PROTOCOL/ACTIVATE message buffers is not prepared for the case that those may be non-linear. We now linearize all such buffers before they are delivered up to the generic reception layer. In order for the commit to apply cleanly to 'net' and 'stable', we do the change in the function tipc_udp_recv() for now. Later, we will post a commit to 'net-next' moving the linearization to generic code, in tipc_named_rcv() and tipc_link_proto_rcv(). Fixes: commit d0f91938bede ("tipc: add ip/udp media type") Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-25tipc: link_is_bc_sndlink() can be staticWu Fengguang
TO: "David S. Miller" <davem@davemloft.net> CC: netdev@vger.kernel.org CC: Jon Maloy <jon.maloy@ericsson.com> CC: Ying Xue <ying.xue@windriver.com> CC: tipc-discussion@lists.sourceforge.net CC: linux-kernel@vger.kernel.org Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Acked-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: clean up unused code and structuresJon Paul Maloy
After the previous changes in this series, we can now remove some unused code and structures, both in the broadcast, link aggregation and link code. There are no functional changes in this commit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: ensure binding table initial distribution is sent via first linkJon Paul Maloy
Correct synchronization of the broadcast link at first contact between two nodes is dependent on the assumption that the binding table "bulk" update passes via the same link as the initial broadcast syncronization message, i.e., via the first link that is established. This is not guaranteed in the current implementation. If two link come up very close to each other in time, the "bulk" may quite well pass via the second link, and hence void the guarantee of a correct initial synchronization before the broadcast link is opened. This commit makes two small changes to strengthen this guarantee. 1) We let the second established link occupy slot 1 of the "active_links" array, while the first link will retain slot 0. (This is in reality a cosmetic change, we could just as well keep the current, opposite order) 2) We let the name distributor always use link selector/slot 0 when it sends it binding table updates. The extra traffic bias on the first link caused by this change should be negligible, since binding table updates constitutes a very small fraction of the total traffic. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: eliminate link's reference to owner nodeJon Paul Maloy
With the recent commit series, we have established a one-way dependency between the link aggregation (struct tipc_node) instances and their pertaining tipc_link instances. This has enabled quite significant code and structure simplifications. In this commit, we eliminate the field 'owner', which points to an instance of struct tipc_node, from struct tipc_link, and replace it with a pointer to struct net, which is the only external reference now needed by a link instance. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: eliminate redundant buffer cloning at transmissionJon Paul Maloy
Since all packet transmitters (link, bcast, discovery) are now sending consumable buffer clones to the bearer layer, we can remove the redundant buffer cloning that is perfomed in the lower level functions tipc_l2_send_msg() and tipc_udp_send_msg(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: let neighbor discoverer tranmsit consumable buffersJon Paul Maloy
The neighbor discovery function currently uses the function tipc_bearer_send() for transmitting packets, assuming that the sent buffers are not consumed by the called function. We want to change this, in order to avoid unnecessary buffer cloning elswhere in the code. This commit introduces a new function tipc_bearer_skb() which consumes the sent buffers, and let the discoverer functions use this new call instead. The discoverer does now itself perform the cloning when that is necessary. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: introduce jumbo frame support for broadcastJon Paul Maloy
Until now, we have only been supporting a fix MTU size of 1500 bytes for all broadcast media, irrespective of their actual capability. We now make the broadcast MTU adaptable to the carrying media, i.e., we use the smallest MTU supported by any of the interfaces attached to TIPC. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: simplify bearer level broadcastJon Paul Maloy
Until now, we have been keeping track of the exact set of broadcast destinations though the help structure tipc_node_map. This leads us to have to maintain a whole infrastructure for supporting this, including a pseudo-bearer and a number of functions to manipulate both the bearers and the node map correctly. Apart from the complexity, this approach is also limiting, as struct tipc_node_map only can support cluster local broadcast if we want to avoid it becoming excessively large. We want to eliminate this limitation, in order to enable introduction of scoped multicast in the future. A closer analysis reveals that it is unnecessary maintaining this "full set" overview; it is sufficient to keep a counter per bearer, indicating how many nodes can be reached via this bearer at the moment. The protocol is now robust enough to handle transitional discrepancies between the nominal number of reachable destinations, as expected by the broadcast protocol itself, and the number which is actually reachable at the moment. The initial broadcast synchronization, in conjunction with the retransmission mechanism, ensures that all packets will eventually be acknowledged by the correct set of destinations. This commit introduces these changes. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: let broadcast packet reception use new link receive functionJon Paul Maloy
The code path for receiving broadcast packets is currently distinct from the unicast path. This leads to unnecessary code and data duplication, something that can be avoided with some effort. We now introduce separate per-peer tipc_link instances for handling broadcast packet reception. Each receive link keeps a pointer to the common, single, broadcast link instance, and can hence handle release and retransmission of send buffers as if they belonged to the own instance. Furthermore, we let each unicast link instance keep a reference to both the pertaining broadcast receive link, and to the common send link. This makes it possible for the unicast links to easily access data for broadcast link synchronization, as well as for carrying acknowledges for received broadcast packets. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: introduce capability bit for broadcast synchronizationJon Paul Maloy
Until now, we have tried to support both the newer, dedicated broadcast synchronization mechanism along with the older, less safe, RESET_MSG/ ACTIVATE_MSG based one. The latter method has turned out to be a hazard in a highly dynamic cluster, so we find it safer to disable it completely when we find that the former mechanism is supported by the peer node. For this purpose, we now introduce a new capabability bit, TIPC_BCAST_SYNCH, to inform any peer nodes that dedicated broadcast syncronization is supported by the present node. The new bit is conveyed between peers in the 'capabilities' field of neighbor discovery messages. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: let broadcast transmission use new link transmit functionJon Paul Maloy
This commit simplifies the broadcast link transmission function, by leveraging previous changes to the link transmission function and the broadcast transmission link life cycle. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: make struct tipc_link generic to support broadcastJon Paul Maloy
Realizing that unicast is just a special case of broadcast, we also see that we can go in the other direction, i.e., that modest changes to the current unicast link can make it generic enough to support broadcast. The following changes are introduced here: - A new counter ("ackers") in struct tipc_link, to indicate how many peers need to ack a packet before it can be released. - A corresponding counter in the skb user area, to keep track of how many peers a are left to ack before a buffer can be released. - A new counter ("acked"), to keep persistent track of how far a peer has acked at the moment, i.e., where in the transmission queue to start updating buffers when the next ack arrives. This is to avoid double acknowledgements from a peer, with inadvertent relase of packets as a result. - A more generic tipc_link_retrans() function, where retransmit starts from a given sequence number, instead of the first packet in the transmision queue. This is to minimize the number of retransmitted packets on the broadcast media. When the new functionality is taken into use in the next commits, we expect it to have minimal effect on unicast mode performance. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: use explicit allocation of broadcast send linkJon Paul Maloy
The broadcast link instance (struct tipc_link) used for sending is currently aggregated into struct tipc_bclink. This means that we cannot use the regular tipc_link_create() function for initiating the link, but do instead have to initiate numerous fields directly from the bcast_init() function. We want to reduce dependencies between the broadcast functionality and the inner workings of tipc_link. In this commit, we introduce a new function tipc_bclink_create() to link.c, and allocate the instance of the link separately using this function. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: make link implementation independent from struct tipc_bearerJon Paul Maloy
In reality, the link implementation is already independent from struct tipc_bearer, in that it doesn't store any reference to it. However, we still pass on a pointer to a bearer instance in the function tipc_link_create(), just to have it extract some initialization information from it. I later commits, we need to create instances of tipc_link without having any associated struct tipc_bearer. To facilitate this, we want to extract the initialization data already in the creator function in node.c, before calling tipc_link_create(), and pass this info on as individual parameters in the call. This commit introduces this change. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: create broadcast transmission link at namespace initJon Paul Maloy
The broadcast transmission link is currently instantiated when the network subsystem is started, i.e., on order from user space via netlink. This forces the broadcast transmission code to do unnecessary tests for the existence of the transmission link, as well in single mode node as in network mode. In this commit, we do instead create the link during initialization of the name space, and remove it when it is stopped. The fact that the transmission link now has a guaranteed longer life cycle than any of its potential clients paves the way for further code simplifcations and optimizations. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: move broadcast link lock to struct tipc_netJon Paul Maloy
The broadcast lock will need to be acquired outside bcast.c in a later commit. For this reason, we move the lock to struct tipc_net. Consistent with the changes in the previous commit, we also introducee two new functions tipc_bcast_lock() and tipc_bcast_unlock(). The code that is currently using tipc_bclink_lock()/unlock() will be phased out during the coming commits in this series. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24tipc: move bcast definitions to bcast.cJon Paul Maloy
Currently, a number of structure and function definitions related to the broadcast functionality are unnecessarily exposed in the file bcast.h. This obscures the fact that the external interface towards the broadcast link in fact is very narrow, and causes unnecessary recompilations of other files when anything changes in those definitions. In this commit, we move as many of those definitions as is currently possible to the file bcast.c. We also rename the structure 'tipc_bclink' to 'tipc_bc_base', both since the name does not correctly describe the contents of this struct, and will do so even less in the future, and because we want to use the term 'link' more appropriately in the functionality introduced later in this series. Finally, we rename a couple of functions, such as tipc_bclink_xmit() and others that will be kept in the future, to include the term 'bcast' instead. There are no functional changes in this commit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/ipv6/xfrm6_output.c net/openvswitch/flow_netlink.c net/openvswitch/vport-gre.c net/openvswitch/vport-vxlan.c net/openvswitch/vport.c net/openvswitch/vport.h The openvswitch conflicts were overlapping changes. One was the egress tunnel info fix in 'net' and the other was the vport ->send() op simplification in 'net-next'. The xfrm6_output.c conflicts was also a simplification overlapping a bug fix. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22tipc: conditionally expand buffer headroom over udp tunnelJon Paul Maloy
In commit d999297c3dbbe ("tipc: reduce locking scope during packet reception") we altered the packet retransmission function. Since then, when restransmitting packets, we create a clone of the original buffer using __pskb_copy(skb, MIN_H_SIZE), where MIN_H_SIZE is the size of the area we want to have copied, but also the smallest possible TIPC packet size. The value of MIN_H_SIZE is 24. Unfortunately, __pskb_copy() also has the effect that the headroom of the cloned buffer takes the size MIN_H_SIZE. This is too small for carrying the packet over the UDP tunnel bearer, which requires a minimum headroom of 28 bytes. A change to just use pskb_copy() lets the clone inherit the original headroom of 80 bytes, but also assumes that the copied data area is of at least that size, something that is not always the case. So that is not a viable solution. We now fix this by adding a check for sufficient headroom in the transmit function of udp_media.c, and expanding it when necessary. Fixes: commit d999297c3dbbe ("tipc: reduce locking scope during packet reception") Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22tipc: allow non-linear first fragment bufferJon Paul Maloy
The current code for message reassembly is erroneously assuming that the the first arriving fragment buffer always is linear, and then goes ahead resetting the fragment list of that buffer in anticipation of more arriving fragments. However, if the buffer already happens to be non-linear, we will inadvertently drop the already attached fragment list, and later on trig a BUG() in __pskb_pull_tail(). We see this happen when running fragmented TIPC multicast across UDP, something made possible since commit d0f91938bede ("tipc: add ip/udp media type") We fix this by not resetting the fragment list when the buffer is non- linear, and by initiatlizing our private fragment list tail pointer to the tail of the existing fragment list. Fixes: commit d0f91938bede ("tipc: add ip/udp media type") Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22tipc: extend broadcast link window sizeJon Paul Maloy
The default fix broadcast window size is currently set to 20 packets. This is a very low value, set at a time when we were still testing on 10 Mb/s hubs, and a change to it is long overdue. Commit 7845989cb4b3da1db ("net: tipc: fix stall during bclink wakeup procedure") revealed a problem with this low value. For messages of importance LOW, the backlog queue limit will be calculated to 30 packets, while a single, maximum sized message of 66000 bytes, carried across a 1500 MTU network consists of 46 packets. This leads to the following scenario (among others leading to the same situation): 1: Msg 1 of 46 packets is sent. 20 packets go to the transmit queue, 26 packets to the backlog queue. 2: Msg 2 of 46 packets is attempted sent, but rejected because there is no more space in the backlog queue at this level. The sender is added to the wakeup queue with a "pending packets chain size" number of 46. 3: Some packets in the transmit queue are acked and released. We try to wake up the sender, but the pending size of 46 is bigger than the LOW wakeup limit of 30, so this doesn't happen. 5: Subsequent acks releases all the remaining buffers. Each time we test for the wakeup criteria and find that 46 still is larger than 30, even after both the transmit and the backlog queues are empty. 6: The sender is never woken up and given a chance to send its message. He is stuck. We could now loosen the wakeup criteria (used by link_prepare_wakeup()) to become equal to the send criteria (used by tipc_link_xmit()), i.e., by ignoring the "pending packets chain size" value altogether, or we can just increase the queue limits so that the criteria can be satisfied anyway. There are good reasons (potentially multiple waiting senders) to not opt for the former solution, so we choose the latter one. This commit fixes the problem by giving the broadcast link window a default value of 50 packets. We also introduce a new minimum link window size BCLINK_MIN_WIN of 32, which is enough to always avoid the described situation. Finally, in order to not break any existing users which may set the window explicitly, we enforce that the window is set to the new minimum value in case the user is trying to set it to anything lower. Fixes: 7845989cb4b3da1db ("net: tipc: fix stall during bclink wakeup procedure") Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/usb/asix_common.c net/ipv4/inet_connection_sock.c net/switchdev/switchdev.c In the inet_connection_sock.c case the request socket hashing scheme is completely different in net-next. The other two conflicts were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-16tipc: update node FSM when peer RESET message is receivedJon Paul Maloy
The change made in the previous commit revealed a small flaw in the way the node FSM is updated. When the function tipc_node_link_down() is called for the last link to a node, we should check whether this was caused by a local reset or by a received RESET message from the peer. In the latter case, we can directly issue a PEER_LOST_CONTACT_EVT to the node FSM, so that it is ready to re-establish contact. If this is not done, the peer node will sometimes have to go through a second establish cycle before the link becomes stable. We fix this in this commit by conditionally issuing the mentioned event in the function tipc_node_link_down(). We also move LINK_RESET FSM even away from the link_reset() function and into the caller function, partially because it is easier to follow the code when state changes are gathered at a limited number of locations, partially because there will be cases in future commits where we don't want the link to go RESET mode when link_reset() is called. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>