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* tipc: fix problem with parallel link synchronization mechanismJon Paul Maloy2015-04-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we try to accumulate arrived packets in the links's 'deferred' queue during the parallel link syncronization phase. This entails two problems: - With an unlucky combination of arriving packets the algorithm may go into a lockstep with the out-of-sequence handling function, where the synch mechanism is adding a packet to the deferred queue, while the out-of-sequence handling is retrieving it again, thus ending up in a loop inside the node_lock scope. - Even if this is avoided, the link will very often send out unnecessary protocol messages, in the worst case leading to redundant retransmissions. We fix this by just dropping arriving packets on the upcoming link during the synchronization phase, thus relying on the retransmission protocol to resolve the situation once the two links have arrived to a synchronized state. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> 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>
* tipc: remove wrong use of NLM_F_MULTINicolas Dichtel2015-04-29
| | | | | | | | | | | | | | | | | NLM_F_MULTI must be used only when a NLMSG_DONE message is sent. In fact, it is sent only at the end of a dump. Libraries like libnl will wait forever for NLMSG_DONE. Fixes: 35b9dd7607f0 ("tipc: add bearer get/dump to new netlink api") Fixes: 7be57fc69184 ("tipc: add link get/dump to new netlink api") Fixes: 46f15c6794fb ("tipc: add media get/dump to new netlink api") CC: Richard Alpe <richard.alpe@ericsson.com> CC: Jon Maloy <jon.maloy@ericsson.com> CC: Ying Xue <ying.xue@windriver.com> CC: tipc-discussion@lists.sourceforge.net Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: fix node refcount issueErik Hugne2015-04-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When link statistics is dumped over netlink, we iterate over the list of peer nodes and append each links statistics to the netlink msg. In the case where the dump is resumed after filling up a nlmsg, the node refcnt is decremented without having been incremented previously which may cause the node reference to be freed. When this happens, the following info/stacktrace will be generated, followed by a crash or undefined behavior. We fix this by removing the erroneous call to tipc_node_put inside the loop that iterates over nodes. [ 384.312303] INFO: trying to register non-static key. [ 384.313110] the code is fine but needs lockdep annotation. [ 384.313290] turning off the locking correctness validator. [ 384.313290] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.0.0+ #13 [ 384.313290] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 384.313290] ffff88003c6d0290 ffff88003cc03ca8 ffffffff8170adf1 0000000000000007 [ 384.313290] ffffffff82728730 ffff88003cc03d38 ffffffff810a6a6d 00000000001d7200 [ 384.313290] ffff88003c6d0ab0 ffff88003cc03ce8 0000000000000285 0000000000000001 [ 384.313290] Call Trace: [ 384.313290] <IRQ> [<ffffffff8170adf1>] dump_stack+0x4c/0x65 [ 384.313290] [<ffffffff810a6a6d>] __lock_acquire+0xf3d/0xf50 [ 384.313290] [<ffffffff810a7375>] lock_acquire+0xd5/0x290 [ 384.313290] [<ffffffffa0043e8c>] ? link_timeout+0x1c/0x170 [tipc] [ 384.313290] [<ffffffffa0043e70>] ? link_state_event+0x4e0/0x4e0 [tipc] [ 384.313290] [<ffffffff81712890>] _raw_spin_lock_bh+0x40/0x80 [ 384.313290] [<ffffffffa0043e8c>] ? link_timeout+0x1c/0x170 [tipc] [ 384.313290] [<ffffffffa0043e8c>] link_timeout+0x1c/0x170 [tipc] [ 384.313290] [<ffffffff810c4698>] call_timer_fn+0xb8/0x490 [ 384.313290] [<ffffffff810c45e0>] ? process_timeout+0x10/0x10 [ 384.313290] [<ffffffff810c5a2c>] run_timer_softirq+0x21c/0x420 [ 384.313290] [<ffffffffa0043e70>] ? link_state_event+0x4e0/0x4e0 [tipc] [ 384.313290] [<ffffffff8105a954>] __do_softirq+0xf4/0x630 [ 384.313290] [<ffffffff8105afdd>] irq_exit+0x5d/0x60 [ 384.313290] [<ffffffff8103ade1>] smp_apic_timer_interrupt+0x41/0x50 [ 384.313290] [<ffffffff817144a0>] apic_timer_interrupt+0x70/0x80 [ 384.313290] <EOI> [<ffffffff8100db10>] ? default_idle+0x20/0x210 [ 384.313290] [<ffffffff8100db0e>] ? default_idle+0x1e/0x210 [ 384.313290] [<ffffffff8100e61a>] arch_cpu_idle+0xa/0x10 [ 384.313290] [<ffffffff81099803>] cpu_startup_entry+0x2c3/0x530 [ 384.313290] [<ffffffff810d2893>] ? clockevents_register_device+0x113/0x200 [ 384.313290] [<ffffffff81038b0f>] start_secondary+0x13f/0x170 Fixes: 8a0f6ebe8494 ("tipc: involve reference counter for node structure") Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: simplify link mtu negotiationJon Paul Maloy2015-04-02
| | | | | | | | | | | | | | | | | | | | | | | | When a link is being established, the two endpoints advertise their respective interface MTU in the transmitted RESET and ACTIVATE messages. If there is any difference, the lower of the two MTUs will be selected for use by both endpoints. However, as a remnant of earlier attempts to introduce TIPC level routing. there also exists an MTU discovery mechanism. If an intermediate node has a lower MTU than the two endpoints, they will discover this through a bisectional approach, and finally adopt this MTU for common use. Since there is no TIPC level routing, and probably never will be, this mechanism doesn't make any sense, and only serves to make the link level protocol unecessarily complex. In this commit, we eliminate the MTU discovery algorithm,and fall back to the simple MTU advertising approach. This change is fully backwards compatible. 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>
* tipc: eliminate delayed link deletion at link failoverJon Paul Maloy2015-04-02
| | | | | | | | | | | | | | | | | | | | | | | | | When a bearer is disabled manually, all its links have to be reset and deleted. However, if there is a remaining, parallel link ready to take over a deleted link's traffic, we currently delay the delete of the removed link until the failover procedure is finished. This is because the remaining link needs to access state from the reset link, such as the last received packet number, and any partially reassembled buffer, in order to perform a successful failover. In this commit, we do instead move the state data over to the new link, so that it can fulfill the procedure autonomously, without accessing any data on the old link. This means that we can now proceed and delete all pertaining links immediately when a bearer is disabled. This saves us from some unnecessary complexity in such situations. We also choose to change the confusing definitions CHANGEOVER_PROTOCOL, ORIGINAL_MSG and DUPLICATE_MSG to the more descriptive TUNNEL_PROTOCOL, FAILOVER_MSG and SYNCH_MSG 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>
* tipc: drop tunneled packet duplicates at receptionJon Paul Maloy2015-04-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit 8b4ed8634f8b3f9aacfc42b4a872d30c36b9e255 ("tipc: eliminate race condition at dual link establishment") we introduced a parallel link synchronization mechanism that guarentees sequential delivery even for users switching from an old to a newly established link. The new mechanism makes it unnecessary to deliver the tunneled duplicate packets back to the old link, as we are currently doing. It is now sufficient to use the last tunneled packet's inner sequence number as synchronization point between the two parallel links, whereafter it can be dropped. In this commit, we drop the duplicate packets arriving on the new link, after updating the synchronization point at each new arrival. Although it would now have been sufficient for the other endpoint to only tunnel the last packet in its send queue, and not the entire queue, we must still do this to maintain compatibility with older nodes. This commit makes it possible to get rid if some complex interaction between the two 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>
* tipc: involve reference counter for node structureYing Xue2015-03-29
| | | | | | | | | | | | | | | | | | | | | TIPC node hash node table is protected with rcu lock on read side. tipc_node_find() is used to look for a node object with node address through iterating the hash node table. As the entire process of what tipc_node_find() traverses the table is guarded with rcu read lock, it's safe for us. However, when callers use the node object returned by tipc_node_find(), there is no rcu read lock applied. Therefore, this is absolutely unsafe for callers of tipc_node_find(). Now we introduce a reference counter for node structure. Before tipc_node_find() returns node object to its caller, it first increases the reference counter. Accordingly, after its caller used it up, it decreases the counter again. This can prevent a node being used by one thread from being freed by another thread. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Jon Maloy <jon.maloy@ericson.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: fix potential deadlock when all links are resetYing Xue2015-03-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ 60.988363] ====================================================== [ 60.988754] [ INFO: possible circular locking dependency detected ] [ 60.989152] 3.19.0+ #194 Not tainted [ 60.989377] ------------------------------------------------------- [ 60.989781] swapper/3/0 is trying to acquire lock: [ 60.990079] (&(&n_ptr->lock)->rlock){+.-...}, at: [<ffffffffa0006dca>] tipc_link_retransmit+0x1aa/0x240 [tipc] [ 60.990743] [ 60.990743] but task is already holding lock: [ 60.991106] (&(&bclink->lock)->rlock){+.-...}, at: [<ffffffffa00004be>] tipc_bclink_lock+0x8e/0xa0 [tipc] [ 60.991738] [ 60.991738] which lock already depends on the new lock. [ 60.991738] [ 60.992174] [ 60.992174] the existing dependency chain (in reverse order) is: [ 60.992174] -> #1 (&(&bclink->lock)->rlock){+.-...}: [ 60.992174] [<ffffffff810a9c0c>] lock_acquire+0x9c/0x140 [ 60.992174] [<ffffffff8179c41f>] _raw_spin_lock_bh+0x3f/0x50 [ 60.992174] [<ffffffffa00004be>] tipc_bclink_lock+0x8e/0xa0 [tipc] [ 60.992174] [<ffffffffa0000f57>] tipc_bclink_add_node+0x97/0xf0 [tipc] [ 60.992174] [<ffffffffa0011815>] tipc_node_link_up+0xf5/0x110 [tipc] [ 60.992174] [<ffffffffa0007783>] link_state_event+0x2b3/0x4f0 [tipc] [ 60.992174] [<ffffffffa00193c0>] tipc_link_proto_rcv+0x24c/0x418 [tipc] [ 60.992174] [<ffffffffa0008857>] tipc_rcv+0x827/0xac0 [tipc] [ 60.992174] [<ffffffffa0002ca3>] tipc_l2_rcv_msg+0x73/0xd0 [tipc] [ 60.992174] [<ffffffff81646e66>] __netif_receive_skb_core+0x746/0x980 [ 60.992174] [<ffffffff816470c1>] __netif_receive_skb+0x21/0x70 [ 60.992174] [<ffffffff81647295>] netif_receive_skb_internal+0x35/0x130 [ 60.992174] [<ffffffff81648218>] napi_gro_receive+0x158/0x1d0 [ 60.992174] [<ffffffff81559e05>] e1000_clean_rx_irq+0x155/0x490 [ 60.992174] [<ffffffff8155c1b7>] e1000_clean+0x267/0x990 [ 60.992174] [<ffffffff81647b60>] net_rx_action+0x150/0x360 [ 60.992174] [<ffffffff8105ec43>] __do_softirq+0x123/0x360 [ 60.992174] [<ffffffff8105f12e>] irq_exit+0x8e/0xb0 [ 60.992174] [<ffffffff8179f9f5>] do_IRQ+0x65/0x110 [ 60.992174] [<ffffffff8179da6f>] ret_from_intr+0x0/0x13 [ 60.992174] [<ffffffff8100de9f>] arch_cpu_idle+0xf/0x20 [ 60.992174] [<ffffffff8109dfa6>] cpu_startup_entry+0x2f6/0x3f0 [ 60.992174] [<ffffffff81033cda>] start_secondary+0x13a/0x150 [ 60.992174] -> #0 (&(&n_ptr->lock)->rlock){+.-...}: [ 60.992174] [<ffffffff810a8f7d>] __lock_acquire+0x163d/0x1ca0 [ 60.992174] [<ffffffff810a9c0c>] lock_acquire+0x9c/0x140 [ 60.992174] [<ffffffff8179c41f>] _raw_spin_lock_bh+0x3f/0x50 [ 60.992174] [<ffffffffa0006dca>] tipc_link_retransmit+0x1aa/0x240 [tipc] [ 60.992174] [<ffffffffa0001e11>] tipc_bclink_rcv+0x611/0x640 [tipc] [ 60.992174] [<ffffffffa0008646>] tipc_rcv+0x616/0xac0 [tipc] [ 60.992174] [<ffffffffa0002ca3>] tipc_l2_rcv_msg+0x73/0xd0 [tipc] [ 60.992174] [<ffffffff81646e66>] __netif_receive_skb_core+0x746/0x980 [ 60.992174] [<ffffffff816470c1>] __netif_receive_skb+0x21/0x70 [ 60.992174] [<ffffffff81647295>] netif_receive_skb_internal+0x35/0x130 [ 60.992174] [<ffffffff81648218>] napi_gro_receive+0x158/0x1d0 [ 60.992174] [<ffffffff81559e05>] e1000_clean_rx_irq+0x155/0x490 [ 60.992174] [<ffffffff8155c1b7>] e1000_clean+0x267/0x990 [ 60.992174] [<ffffffff81647b60>] net_rx_action+0x150/0x360 [ 60.992174] [<ffffffff8105ec43>] __do_softirq+0x123/0x360 [ 60.992174] [<ffffffff8105f12e>] irq_exit+0x8e/0xb0 [ 60.992174] [<ffffffff8179f9f5>] do_IRQ+0x65/0x110 [ 60.992174] [<ffffffff8179da6f>] ret_from_intr+0x0/0x13 [ 60.992174] [<ffffffff8100de9f>] arch_cpu_idle+0xf/0x20 [ 60.992174] [<ffffffff8109dfa6>] cpu_startup_entry+0x2f6/0x3f0 [ 60.992174] [<ffffffff81033cda>] start_secondary+0x13a/0x150 [ 60.992174] [ 60.992174] other info that might help us debug this: [ 60.992174] [ 60.992174] Possible unsafe locking scenario: [ 60.992174] [ 60.992174] CPU0 CPU1 [ 60.992174] ---- ---- [ 60.992174] lock(&(&bclink->lock)->rlock); [ 60.992174] lock(&(&n_ptr->lock)->rlock); [ 60.992174] lock(&(&bclink->lock)->rlock); [ 60.992174] lock(&(&n_ptr->lock)->rlock); [ 60.992174] [ 60.992174] *** DEADLOCK *** [ 60.992174] [ 60.992174] 3 locks held by swapper/3/0: [ 60.992174] #0: (rcu_read_lock){......}, at: [<ffffffff81646791>] __netif_receive_skb_core+0x71/0x980 [ 60.992174] #1: (rcu_read_lock){......}, at: [<ffffffffa0002c35>] tipc_l2_rcv_msg+0x5/0xd0 [tipc] [ 60.992174] #2: (&(&bclink->lock)->rlock){+.-...}, at: [<ffffffffa00004be>] tipc_bclink_lock+0x8e/0xa0 [tipc] [ 60.992174] The correct the sequence of grabbing n_ptr->lock and bclink->lock should be that the former is first held and the latter is then taken, which exactly happened on CPU1. But especially when the retransmission of broadcast link is failed, bclink->lock is first held in tipc_bclink_rcv(), and n_ptr->lock is taken in link_retransmit_failure() called by tipc_link_retransmit() subsequently, which is demonstrated on CPU0. As a result, deadlock occurs. If the order of holding the two locks happening on CPU0 is reversed, the deadlock risk will be relieved. Therefore, the node lock taken in link_retransmit_failure() originally is moved to tipc_bclink_rcv() so that it's obtained before bclink lock. But the precondition of the adjustment of node lock is that responding to bclink reset event must be moved from tipc_bclink_unlock() to tipc_node_unlock(). Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: eliminate race condition at dual link establishmentJon Paul Maloy2015-03-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | Despite recent improvements, the establishment of dual parallel links still has a small glitch where messages can bypass each other. When the second link in a dual-link configuration is established, part of the first link's traffic will be steered over to the new link. Although we do have a mechanism to ensure that packets sent before and after the establishment of the new link arrive in sequence to the destination node, this is not enough. The arriving messages will still be delivered upwards in different threads, something entailing a risk of message disordering during the transition phase. To fix this, we introduce a synchronization mechanism between the two parallel links, so that traffic arriving on the new link cannot be added to its input queue until we are guaranteed that all pre-establishment messages have been delivered on the old, parallel link. This problem seems to always have been around, but its occurrence is so rare that it has not been noticed until recent intensive testing. Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: clean up handling of link congestionJon Paul Maloy2015-03-25
| | | | | | | | | | | | | | | | | | | | After the recent changes in message importance handling it becomes possible to simplify handling of messages and sockets when we encounter link congestion. We merge the function tipc_link_cong() into link_schedule_user(), and simplify the code of the latter. The code should now be easier to follow, especially regarding return codes and handling of the message that caused the situation. In case the scheduling function is unable to pre-allocate a wakeup message buffer, it now returns -ENOBUFS, which is a more correct code than the previously used -EHOSTUNREACH. Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: introduce starvation free send algorithmJon Paul Maloy2015-03-25
| | | | | | | | | | | | | | | | | | | | | | | Currently, we only use a single counter; the length of the backlog queue, to determine whether a message should be accepted to the queue or not. Each time a message is being sent, the queue length is compared to a threshold value for the message's importance priority. If the queue length is beyond this threshold, the message is rejected. This algorithm implies a risk of starvation of low importance senders during very high load, because it may take a long time before the backlog queue has decreased enough to accept a lower level message. We now eliminate this risk by introducing a counter for each importance priority. When a message is sent, we check only the queue level for that particular message's priority. If that is ok, the message can be added to the backlog, irrespective of the queue level for other priorities. This way, each level is guaranteed a certain portion of the total bandwidth, and any risk of starvation is eliminated. Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: do not report -EHOSTUNREACH for failed local deliveryErik Hugne2015-03-19
| | | | | | | | | | | | | | | | | | | | Since commit 1186adf7df04 ("tipc: simplify message forwarding and rejection in socket layer") -EHOSTUNREACH is propagated back to the sending process if we fail to deliver the message to another socket local to the node. This is wrong, host unreachable should only be reported when the destination port/name does not exist in the cluster, and that check is always done before sending the message. Also, this introduces inconsistent sendmsg() behavior for local/remote destinations. Errors occurring on the receiving side should not trickle up to the sender. If message delivery fails TIPC should either discard the packet or reject it back to the sender based on the destination droppable option. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Acked-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: clean up handling of message prioritiesJon Paul Maloy2015-03-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Messages transferred by TIPC are assigned an "importance priority", -an integer value indicating how to treat the message when there is link or destination socket congestion. There is no separate header field for this value. Instead, the message user values have been chosen in ascending order according to perceived importance, so that the message user field can be used for this. This is not a good solution. First, we have many more users than the needed priority levels, so we end up with treating more priority levels than necessary. Second, the user field cannot always accurately reflect the priority of the message. E.g., a message fragment packet should really have the priority of the enveloped user data message, and not the priority of the MSG_FRAGMENTER user. Until now, we have been working around this problem in different ways, but it is now time to implement a consistent way of handling such priorities, although still within the constraint that we cannot allocate any more bits in the regular data message header for this. In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE, that will be the only one used apart from the four (lower) user data levels. All non-data messages map down to this priority. Furthermore, we take some free bits from the MSG_FRAGMENTER header and allocate them to store the priority of the enveloped message. We then adjust the functions msg_importance()/msg_set_importance() so that they read/set the correct header fields depending on user type. This small protocol change is fully compatible, because the code at the receiving end of a link currently reads the importance level only from user data messages, where there is no change. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: split link outqueueJon Paul Maloy2015-03-14
| | | | | | | | | | | | | | | | | | | | struct tipc_link contains one single queue for outgoing packets, where both transmitted and waiting packets are queued. This infrastructure is hard to maintain, because we need to keep a number of fields to keep track of which packets are sent or unsent, and the number of packets in each category. A lot of code becomes simpler if we split this queue into a transmission queue, where sent/unacknowledged packets are kept, and a backlog queue, where we keep the not yet sent packets. In this commit we do this separation. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> 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>
* tipc: eliminate unnecessary call to broadcast ack functionJon Paul Maloy2015-03-14
| | | | | | | | | | | | | | | | | | | | | | The unicast packet header contains a broadcast acknowledge sequence number, that may need to be conveyed to the broadcast link for proper treatment. Currently, the function tipc_rcv(), which is on the most critical data path, calls the function tipc_bclink_acknowledge() to have this done. This call is made for each received packet, and results in the unconditional grabbing of the broadcast link spinlock. This is unnecessary, since we can see directly from tipc_rcv() if the acknowledged number differs from what has been previously acked from the node in question. In the vast majority of cases the numbers won't differ, and there is nothing to update. We now make the call to tipc_bclink_acknowledge() conditional to that the two ack values differ. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> 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>
* tipc: extract bundled buffers by cloning instead of copyingJon Paul Maloy2015-03-14
| | | | | | | | | | | | | | | | | When we currently extract a bundled buffer from a message bundle in the function tipc_msg_extract(), we allocate a new buffer and explicitly copy the linear data area. This is unnecessary, since we can just clone the buffer and do skb_pull() on the clone to move the data pointer to the correct position. This is what we do in this commit. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> 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>
* tipc: eliminate unnecessary linearization of incoming buffersJon Paul Maloy2015-03-14
| | | | | | | | | | | | | | | | | | | Currently, TIPC linearizes all incoming buffers directly at reception before passing them upwards in the stack. This is clearly a waste of CPU resources, and must be avoided. In this commit, we eliminate this unnecessary linearization. We still ensure that at least the message header is linear, and that the buffer is linearized where this is still needed, i.e. when unbundling and when reversing messages. In addition, we ensure that fragmented messages are validated after reassembly before delivering them upwards in the stack. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> 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>
* tipc: move message validation function to msg.cJon Paul Maloy2015-03-14
| | | | | | | | | | | | The function link_buf_validate() is in reality re-entrant and context independent, and will in later commits be called from several locations. Therefore, we move it to msg.c, make it outline and rename the it to tipc_msg_validate(). We also redesign the function to make proper use of pskb_may_pull() Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: ensure that idle links are deleted when a bearer is disabledJon Paul Maloy2015-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | commit afaa3f65f65fda2e7b190aac7e2a75d9a2a77cb6 (tipc: purge links when bearer is disabled) was an attempt to resolve a problem that turned out to have a more profound reason. When we disable a bearer, we delete all its pertaining links if there is no other bearer to perform failover to, or if the module is shutting down. In case there are dual bearers, we wait with deleting links until the failover procedure is finished. However, this misses the case when a link on the removed bearer was already down, so that there will be no failover procedure to finish the link delete. This causes confusion if a new bearer is added to replace the removed one, and also entails a small memory leak. This commit takes the current state of the link into account when deciding when to delete it, and also reverses the above-mentioned commit. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: fix bug in link failover handlingJon Paul Maloy2015-03-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | In commit c637c1035534867b85b78b453c38c495b58e2c5a ("tipc: resolve race problem at unicast message reception") we introduced a new mechanism for delivering buffers upwards from link to socket layer. That code contains a bug in how we handle the new link input queue during failover. When a link is reset, some of its users may be blocked because of congestion, and in order to resolve this, we add any pending wakeup pseudo messages to the link's input queue, and deliver them to the socket. This misses the case where the other, remaining link also may have congested users. Currently, the owner node's reference to the remaining link's input queue is unconditionally overwritten by the reset link's input queue. This has the effect that wakeup events from the remaining link may be unduely delayed (but not lost) for a potentially long period. We fix this by adding the pending events from the reset link to the input queue that is currently referenced by the node, whichever one it is. This commit should be applied to both net and net-next. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: nl compat add noop and remove legacy nl frameworkRichard Alpe2015-02-09
| | | | | | | | | | | | | Add TIPC_CMD_NOOP to compat layer and remove the old framework. All legacy nl commands are now converted to the compat layer in netlink_compat.c. Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: convert legacy nl link stat reset to nl compatRichard Alpe2015-02-09
| | | | | | | | | | Convert TIPC_CMD_RESET_LINK_STATS to compat doit. Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: convert legacy nl link prop set to nl compatRichard Alpe2015-02-09
| | | | | | | | | | | | | | | Convert setting of link proprieties to compat doit calls. Commands converted in this patch: TIPC_CMD_SET_LINK_TOL TIPC_CMD_SET_LINK_PRI TIPC_CMD_SET_LINK_WINDOW Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: convert legacy nl link stat to nl compatRichard Alpe2015-02-09
| | | | | | | | | | | | | Add functionality for safely appending string data to a TLV without keeping write count in the caller. Convert TIPC_CMD_SHOW_LINK_STATS to compat dumpit. Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: move and rename the legacy nl api to "nl compat"Richard Alpe2015-02-09
| | | | | | | | | | | | | The new netlink API is no longer "v2" but rather the standard API and the legacy API is now "nl compat". We split them into separate start/stop and put them in different files in order to further distinguish them. Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: resolve race problem at unicast message receptionJon Paul Maloy2015-02-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TIPC handles message cardinality and sequencing at the link layer, before passing messages upwards to the destination sockets. During the upcall from link to socket no locks are held. It is therefore possible, and we see it happen occasionally, that messages arriving in different threads and delivered in sequence still bypass each other before they reach the destination socket. This must not happen, since it violates the sequentiality guarantee. We solve this by adding a new input buffer queue to the link structure. Arriving messages are added safely to the tail of that queue by the link, while the head of the queue is consumed, also safely, by the receiving socket. Sequentiality is secured per socket by only allowing buffers to be dequeued inside the socket lock. Since there may be multiple simultaneous readers of the queue, we use a 'filter' parameter to reduce the risk that they peek the same buffer from the queue, hence also reducing the risk of contention on the receiving socket locks. This solves the sequentiality problem, and seems to cause no measurable performance degradation. A nice side effect of this change is that lock handling in the functions tipc_rcv() and tipc_bcast_rcv() now becomes uniform, something that will enable future simplifications of those functions. 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>
* tipc: reduce usage of context info in socket and linkJon Paul Maloy2015-02-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The most common usage of namespace information is when we fetch the own node addess from the net structure. This leads to a lot of passing around of a parameter of type 'struct net *' between functions just to make them able to obtain this address. However, in many cases this is unnecessary. The own node address is readily available as a member of both struct tipc_sock and tipc_link, and can be fetched from there instead. The fact that the vast majority of functions in socket.c and link.c anyway are maintaining a pointer to their respective base structures makes this option even more compelling. In this commit, we introduce the inline functions tsk_own_node() and link_own_node() to make it easy for functions to fetch the node address from those structs instead of having to pass along and dereference the namespace struct. In particular, we make calls to the msg_xx() functions in msg.{h,c} context independent by directly passing them the own node address as parameter when needed. Those functions should be regarded as leaves in the code dependency tree, and it is hence desirable to keep them namspace unaware. Apart from a potential positive effect on cache behavior, these changes make it easier to introduce the changes that will follow later in this series. 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>
* tipc: separate link starting event from link timeout eventJon Paul Maloy2015-02-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | When a new link instance is created, it is trigged to start by sending it a TIPC_STARTING_EVT, whereafter a regular link reset is applied to it. The starting event is codewise treated as a timeout event, and prompts a link RESET message to be sent to the peer node, carrying a link session identifier. The later link_reset() call nudges this session identifier, whereafter all subsequent RESET messages will be sent out with the new identifier. The latter session number overrides the former, causing the peer to unconditionally accept it irrespective of its current working state. We don't think that this causes any problem, but it is not in accordance with the protocol spec, and may cause confusion when debugging TIPC sessions. To avoid this, we make the starting event distinct from the subsequent timeout events, by not allowing the former to send out any RESET message. This eliminates the described problem. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> 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>
* tipc: add reference count to struct tipc_linkJon Paul Maloy2015-02-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | When a bearer is disabled, all pertaining links will be reset and deleted. However, if there is a second active link towards a killed link's destination, the delete has to be postponed until the failover is finished. During this interval, we currently put the link in zombie mode, i.e., we take it out of traffic, delete its timer, but leave it attached to the owner node structure until all missing packets have been received. When this is done, we detach the link from its node and delete it, assuming that the synchronous timer deletion that was initiated earlier in a different thread has finished. This is unsafe, as the failover may finish before del_timer_sync() has returned in the other thread. We fix this by adding an atomic reference counter of type kref in struct tipc_link. The counter keeps track of the references kept to the link by the owner node and the timer. We then do a conditional delete, based on the reference counter, both after the failover has been finished and when the timer expires, if applicable. Whoever comes last, will actually delete the link. This approach also implies that we can make the deletion of the timer asynchronous. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> 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>
* tipc: fix excessive network event loggingErik Hugne2015-01-26
| | | | | | | | | | | | If a large number of namespaces is spawned on a node and TIPC is enabled in each of these, the excessive printk tracing of network events will cause the system to grind down to a near halt. The traces are still of debug value, so instead of removing them completely we fix it by changing the link state and node availability logging debug traces. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: make tipc random value aware of net namespaceYing Xue2015-01-12
| | | | | | | | | | | After namespace is supported, each namespace should own its private random value. So the global variable representing the random value must be moved to tipc_net structure. Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: make tipc node address support net namespaceYing Xue2015-01-12
| | | | | | | | | | | | | | If net namespace is supported in tipc, each namespace will be treated as a separate tipc node. Therefore, every namespace must own its private tipc node address. This means the "tipc_own_addr" global variable of node address must be moved to tipc_net structure to satisfy the requirement. It's turned out that users also can assign node address for every namespace. Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: make tipc broadcast link support net namespaceYing Xue2015-01-12
| | | | | | | | | | | | | | TIPC broadcast link is statically established and its relevant states are maintained with the global variables: "bcbearer", "bclink" and "bcl". Allowing different namespace to own different broadcast link instances, these variables must be moved to tipc_net structure and broadcast link instances would be allocated and initialized when namespace is created. Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: make bearer list support net namespaceYing Xue2015-01-12
| | | | | | | | | | | | | | Bearer list defined as a global variable is used to store bearer instances. When tipc supports net namespace, bearers created in one namespace must be isolated with others allocated in other namespaces, which requires us that the bearer list(bearer_list) must be moved to tipc_net structure. As a result, a net namespace pointer has to be passed to functions which access the bearer list. Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: make tipc node table aware of net namespaceYing Xue2015-01-12
| | | | | | | | | | | | | | | | | | | | | | | Global variables associated with node table are below: - node table list (node_htable) - node hash table list (tipc_node_list) - node table lock (node_list_lock) - node number counter (tipc_num_nodes) - node link number counter (tipc_num_links) To make node table support namespace, above global variables must be moved to tipc_net structure in order to keep secret for different namespaces. As a consequence, these variables are allocated and initialized when namespace is created, and deallocated when namespace is destroyed. After the change, functions associated with these variables have to utilize a namespace pointer to access them. So adding namespace pointer as a parameter of these functions is the major change made in the commit. Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: involve namespace infrastructureYing Xue2015-01-12
| | | | | | | | | | | | | Involve namespace infrastructure, make the "tipc_net_id" global variable aware of per namespace, and rename it to "net_id". In order that the conversion can be successfully done, an instance of networking namespace must be passed to relevant functions, allowing them to access the "net_id" variable of per namespace. Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: remove unused tipc_link_get_max_pkt routineYing Xue2015-01-12
| | | | | | | Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: remove unnecessary wrapper functions of kernel timer APIsYing Xue2015-01-12
| | | | | | | | | | | | | Not only some wrapper function like k_term_timer() is empty, but also some others including k_start_timer() and k_cancel_timer() don't return back any value to its caller, what's more, there is no any component in the kernel world to do such thing. Therefore, these timer interfaces defined in tipc module should be purged. Signed-off-by: Ying Xue <ying.xue@windriver.com> Tested-by: Tero Aho <Tero.Aho@coriant.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: replace 0 by NULL for pointersFabian Frederick2014-12-31
| | | | | | | | | Fix sparse warning: net/tipc/link.c:1924:40: warning: Using plain integer as NULL pointer Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: fix broadcast wakeup contention after congestionRichard Alpe2014-12-10
| | | | | | | | | | | | | | commit 908344cdda80 ("tipc: fix bug in multicast congestion handling") introduced a race in the broadcast link wakeup functionality. This patch eliminates this broadcast link wakeup race caused by operation on the wakeup list without proper locking. If this race hit and corrupted the list all subsequent wakeup messages would be lost, resulting in a considerable memory leak. Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: use generic SKB list APIs to manage TIPC outgoing packet chainsYing Xue2014-11-26
| | | | | | | | | | Use standard SKB list APIs associated with struct sk_buff_head to manage socket outgoing packet chain and name table outgoing packet chain, having relevant code simpler and more readable. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: use generic SKB list APIs to manage link receive queueYing Xue2014-11-26
| | | | | | | | | Use standard SKB list APIs associated with struct sk_buff_head to manage link's receive queue to simplify its relevant code cemplexity. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: use generic SKB list APIs to manage deferred queue of linkYing Xue2014-11-26
| | | | | | | | | Use standard SKB list APIs associated with struct sk_buff_head to manage link's deferred queue, simplifying relevant code. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: use generic SKB list APIs to manage link transmission queueYing Xue2014-11-26
| | | | | | | | | Use standard SKB list APIs associated with struct sk_buff_head to manage link transmission queue, having relevant code more clean. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: use skb_queue_walk_safe marco to simplify link_prepare_wakeup routineYing Xue2014-11-26
| | | | | | Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: eliminate two pseudo message types of BUNDLE_OPEN and BUNDLE_CLOSEDYing Xue2014-11-26
| | | | | | | | | | | | | | | The pseudo message types of BUNDLE_CLOSED as well as BUNDLE_OPEN are used to flag whether or not more messages can be bundled into a data packet in the outgoing transmission queue. Obviously, no more messages can be appended after the packet has been sent and is waiting to be acknowledged and deleted. These message types do in reality represent a send-side local implementation flag, and are not defined as part of the protocol. It is therefore safe to move it to to where it belongs, that is, the control area (TIPC_SKB_CB) of the buffer. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: clean up the process of link pushing packetsYing Xue2014-11-26
| | | | | | | | | | | In original tipc_link_push_packet(), it pushes messages from protocol message queue, retransmission queue and next_out queue. But as the two first queues are removed, we can simplify its relevant code through deleting tipc_link_push_queue(). Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: remove retransmission queueYing Xue2014-11-26
| | | | | | | | | | | TIPC retransmission queue is intended to record which messages should be retransmitted when bearer is not congested. However, as the retransmission queue becomes useless with the removal of bearer congestion mechanism, it should be removed. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: remove protocol message queueYing Xue2014-11-26
| | | | | | | | | | | | TIPC protocol message queue is intended to save one protocol message when bearer is congested so that the message stored in the queue can be immediately transmitted when bearer congestion is released. However, as now the protocol queue has no mission any more with the removal of bearer congestion mechanism, it should be removed. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: fix sparse warnings in new nl apiRichard Alpe2014-11-24
| | | | | | | | Fix sparse warnings about non-static declaration of static functions in the new tipc netlink API. Signed-off-by: Richard Alpe <richard.alpe@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>