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2014-09-10tipc: fix sparse warningsErik Hugne
This fixes the following sparse warnings: sparse: symbol 'tipc_update_nametbl' was not declared. Should it be static? Also, the function is changed to return bool upon success, rather than a potentially freed pointer. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01tipc: add name distributor resiliency queueErik Hugne
TIPC name table updates are distributed asynchronously in a cluster, entailing a risk of certain race conditions. E.g., if two nodes simultaneously issue conflicting (overlapping) publications, this may not be detected until both publications have reached a third node, in which case one of the publications will be silently dropped on that node. Hence, we end up with an inconsistent name table. In most cases this conflict is just a temporary race, e.g., one node is issuing a publication under the assumption that a previous, conflicting, publication has already been withdrawn by the other node. However, because of the (rtt related) distributed update delay, this may not yet hold true on all nodes. The symptom of this failure is a syslog message: "tipc: Cannot publish {%u,%u,%u}, overlap error". In this commit we add a resiliency queue at the receiving end of the name table distributor. When insertion of an arriving publication fails, we retain it in this queue for a short amount of time, assuming that another update will arrive very soon and clear the conflict. If so happens, we insert the publication, otherwise we drop it. The (configurable) retention value defaults to 2000 ms. Knowing from experience that the situation described above is extremely rare, there is no risk that the queue will accumulate any large number of items. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> 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>
2014-09-01tipc: refactor name table updates out of named packet receive routineErik Hugne
We need to perform the same actions when processing deferred name table updates, so this functionality is moved to a separate function. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> 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>
2014-08-29tipc: fix a potential oopsYing Xue
Commit 6c9808ce09f7 ("tipc: remove port_lock") accidentally involves a potential bug: when tipc socket instance(tsk) is not got with given reference number in tipc_sk_get(), tsk is set to NULL. Subsequently we jump to exit label where to decrease socket reference counter pointed by tsk pointer in tipc_sk_put(). However, As now tsk is NULL, oops may happen because of touching a NULL pointer. Signed-off-by: Ying Xue <ying.xue@windriver.com> Acked-by: Erik Hugne <erik.hugne@ericsson.com> Acked-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: merge struct tipc_port into struct tipc_sockJon Paul Maloy
We complete the merging of the port and socket layer by aggregating the fields of struct tipc_port directly into struct tipc_sock, and moving the combined structure into socket.c. We also move all functions and macros that are not any longer exposed to the rest of the stack into socket.c, and rename them accordingly. Despite the size of this commit, there are no functional changes. We have only made such changes that are necessary due of the removal of struct tipc_port. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: remove files ref.h and ref.cJon Paul Maloy
The reference table is now 'socket aware' instead of being generic, and has in reality become a socket internal table. In order to be able to minimize the API exposed by the socket layer towards the rest of the stack, we now move the reference table definitions and functions into the file socket.c, and rename the functions accordingly. There are no functional changes in this commit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: remove include file port.hJon Paul Maloy
We move the inline functions in the file port.h to socket.c, and modify their names accordingly. We move struct tipc_port and some macros to socket.h. Finally, we remove the file port.h. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: remove source file port.cJon Paul Maloy
In this commit, we move the remaining functions in port.c to socket.c, and give them new names that correspond to their new location. We then remove the file port.c. There are only cosmetic changes to the moved functions. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: remove port_lockJon Paul Maloy
In previous commits we have reduced usage of port_lock to a minimum, and complemented it with usage of bh_lock_sock() at the remaining locations. The purpose has been to remove this lock altogether, since it largely duplicates the role of bh_lock_sock. We are now ready to do this. However, we still need to protect the BH callers from inadvertent release of the socket while they hold a reference to it. We do this by replacing port_lock by a combination of a rw-lock protecting the reference table as such, and updating the socket reference counter while the socket is referenced from BH. This technique is more standard and comprehensible than the previous approach, and turns out to have a positive effect on overall performance. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: replace port pointer with socket pointer in registryJon Paul Maloy
In order to make tipc_sock the only entity referencable from other parts of the stack, we add a tipc_sock pointer instead of a tipc_port pointer to the registry. As a consequence, we also let the function tipc_port_lock() return a pointer to a tipc_sock instead of a tipc_port. We keep the function's name for now, since the lock still is owned by the port. This is another step in the direction of eliminating port_lock, replacing its usage with lock_sock() and bh_lock_sock(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: use registry when scanning socketsJon Paul Maloy
The functions tipc_port_get_ports() and tipc_port_reinit() scan over all sockets/ports to access each of them. This is done by using a dedicated linked list, 'tipc_socks' where all sockets are members. The list is in turn protected by a spinlock, 'port_list_lock', while each socket is locked by using port_lock at the moment of access. In order to reduce complexity and risk of deadlock, we want to get rid of the linked list and the accompanying spinlock. This is what we do in this commit. Instead of the linked list, we use the port registry to scan across the sockets. We also add usage of bh_lock_sock() inside the scope of port_lock in both functions, as a preparation for the complete removal of port_lock. Finally, we move the functions from port.c to socket.c, and rename them to tipc_sk_sock_show() and tipc_sk_reinit() repectively. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: eliminate functions tipc_port_init and tipc_port_destroyJon Paul Maloy
After the latest changes to the socket/port layer the existence of the functions tipc_port_init() and tipc_port_destroy() cannot be justified. They are both called only once, from tipc_sk_create() and tipc_sk_delete() respectively, and their functionality can better be merged into the latter two functions. This also entails that all remaining references to port_lock now are made from inside socket.c, something that will make it easier to remove this lock. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: redefine message acknowledge functionJon Paul Maloy
The function tipc_acknowledge() is a remnant from the obsolete native API. Currently, it grabs port_lock, before building an acknowledge message and sending it to the peer. Since all access to socket members now is protected by the socket lock, it has become unnecessary to grab port_lock here. In this commit, we remove the usage of port_lock, simplify the function, and move it to socket.c, renaming it to tipc_sk_send_ack(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: eliminate port_connect()/port_disconnect() functionsJon Paul Maloy
tipc_port_connect()/tipc_port_disconnect() are remnants of the obsolete native API. Their only task is to grab port_lock and call the functions __tipc_port_connect()/__tipc_port_disconnect() respectively, which will perform the actual state change. Since socket/port exection now is single-threaded the use of port_lock is not needed any more, so we can safely replace the two functions with their lock-free counterparts. In this commit, we remove the two functions. Furthermore, the contents of __tipc_port_disconnect() is so trivial that we choose to eliminate that function too, expanding its functionality into tipc_shutdown(). __tipc_port_connect() is simplified, moved to socket.c, and given the more correct name tipc_sk_finish_conn(). Finally, we eliminate the function auto_connect(), and expand its contents into filter_connect(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: eliminate function tipc_port_shutdown()Jon Paul Maloy
tipc_port_shutdown() is a remnant from the now obsolete native interface. As such it grabs port_lock in order to protect itself from concurrent BH processing. However, after the recent changes to the port/socket upcalls, sockets are now basically single-threaded, and all execution, except the read-only tipc_sk_timer(), is executing within the protection of lock_sock(). So the use of port_lock is not needed here. In this commit we eliminate the whole function, and merge it into its only caller, tipc_shutdown(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: clean up socket timer functionJon Paul Maloy
The last remaining BH upcall to the socket, apart for the message reception function tipc_sk_rcv(), is the timer function. We prefer to let this function continue executing in BH, since it only does read-acces to semi-permanent data, but we make three changes to it: 1) We introduce a bh_lock_sock()/bh_unlock_sock() inside the scope of port_lock. This is a preparation for replacing port_lock with bh_lock_sock() at the locations where it is still used. 2) We move the function from port.c to socket.c, as a further step of eliminating the port code level altogether. 3) We let it make use of the newly introduced tipc_msg_create() function. This enables us to get rid of three context specific functions (port_create_self_abort_msg() etc.) in port.c Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: use message to abort connections when losing contact to nodeJon Paul Maloy
In the current implementation, each 'struct tipc_node' instance keeps a linked list of those ports/sockets that are connected to the node represented by that struct. The purpose of this is to let the node object know which sockets to alert when it loses contact with its peer node, i.e., which sockets need to have their connections aborted. This entails an unwanted direct reference from the node structure back to the port/socket structure, and a need to grab port_lock when we have to make an upcall to the port. We want to get rid of this unecessary BH entry point into the socket, and also eliminate its use of port_lock. In this commit, we instead let the node struct keep list of "connected socket" structs, which each represents a connected socket, but is allocated independently by the node at the moment of connection. If the node loses contact with its peer node, the list is traversed, and a "connection abort" message is created for each entry in the list. The message is sent to it respective connected socket using the ordinary data path, and the receiving socket aborts its connections upon reception of the message. This enables us to get rid of the direct reference from 'struct node' to ´struct port', and another unwanted BH access point to the latter. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: use pseudo message to wake up sockets after link congestionJon Paul Maloy
The current link implementation keeps a linked list of blocked ports/ sockets that is populated when there is link congestion. The purpose of this is to let the link know which users to wake up when the congestion abates. This adds unnecessary complexity to the data structure and the code, since it forces us to involve the link each time we want to delete a socket. It also forces us to grab the spinlock port_lock within the scope of node_lock. We want to get rid of this direct dependence, as well as the deadlock hazard resulting from the usage of port_lock. In this commit, we instead let the link keep list of a "wakeup" pseudo messages for use in such situations. Those messages are sent to the pending sockets via the ordinary message reception path, and wake up the socket's owner when they are received. This enables us to get rid of the 'waiting_ports' linked lists in struct tipc_port that manifest this direct reference. As a consequence, we can eliminate another BH entry into the socket, and hence the need to grab port_lock. This is a further step in our effort to remove port_lock altogether. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23tipc: introduce new function tipc_msg_create()Jon Paul Maloy
The function tipc_msg_init() has turned out to be of limited value in many cases. It take too few parameters to be usable for creating a complete message, it makes too many assumptions about what the message should be used for, and it does not allocate any buffer to be returned to the caller. Therefore, we now introduce the new function tipc_msg_create(), which takes all the parameters needed to create a full message, and returns a buffer of the requested size. The new function will be very useful for the changes we will be doing in later commits in this series. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-19tipc: Fix build.David S. Miller
Missing semicolon in range check fix. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-16tipc: fix message importance range checkErik Hugne
Commit 3b4f302d8578 ("tipc: eliminate redundant locking") introduced a bug by removing the sanity check for message importance, allowing programs to assign any value to the msg_user field. This will mess up the packet reception logic and may cause random link resets. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-29tipc: remove duplicated include from socket.cWei Yongjun
Remove duplicated include. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-28tipc: make tipc_buf_append() more robustJon Paul Maloy
As per comment from David Miller, we try to make the buffer reassembly function more resilient to user errors than it is today. - We check that the "*buf" parameter always is set, since this is mandatory input. - We ensure that *buf->next always is set to NULL before linking in the buffer, instead of relying of the caller to have done this. - We ensure that the "tail" pointer in the head buffer's control block is initialized to NULL when the first fragment arrives. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-20tipc: fix sparse non static symbol warningsWei Yongjun
Fixes the following sparse warnings: net/tipc/socket.c:545:5: warning: symbol 'tipc_sk_proto_rcv' was not declared. Should it be static? net/tipc/socket.c:2015:5: warning: symbol 'tipc_ioctl' was not declared. Should it be static? Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16tipc: ensure sequential message delivery across dual bearersJon Paul Maloy
When we run broadcast packets over dual bearers/interfaces, the current transmission code is flipping bearers between each sent packet, with the purpose of leveraging the double bandwidth available. The receiving bclink is resequencing the packets if needed, so all messages are delivered upwards from the broadcast link in the correct order, even if they may arrive in concurrent interrupts. However, at the moment of delivery upwards to the socket, we release all spinlocks (bclink_lock, node_lock), so it is still possible that arriving messages bypass each other before they reach the socket queue. We fix this by applying the same technique we are using for unicast traffic. We use a link selector (i.e., the last bit of sending port number) to ensure that messages from the same sender socket always are sent over the same bearer. This guarantees sequential delivery between socket pairs, which is sufficient to satisfy the protocol spec, as well as all known user requirements. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16tipc: rename temporarily named functionsJon Paul Maloy
After the previous commit, we can now give the functions with temporary names, such as tipc_link_xmit2(), tipc_msg_build2() etc., their proper names. There are no functional changes in this commit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16tipc: remove unreferenced functionsJon Paul Maloy
We can now remove a number of functions which have become obsolete and unreferenced through this commit series. There are no functional changes in this commit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16tipc: start using the new multicast functionsJon Paul Maloy
In this commit, we convert the socket multicast send function to directly call the new multicast/broadcast function (tipc_bclink_xmit2()) introduced in the previous commit. We do this instead of letting the call go via the now obsolete tipc_port_mcast_xmit(), hence saving a call level and some code complexity. We also remove the initial destination lookup at the message sending side, and replace that with an unconditional lookup at the receiving side, including on the sending node itself. This makes the destination lookup and message transfer more uniform than before. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16tipc: add new functions for multicast and broadcast distributionJon Paul Maloy
We add a new broadcast link transmit function in bclink.c and a new receive function in socket.c. The purpose is to move the branching between external and internal destination down to the link layer, just as we have done with unicast in earlier commits. We also make use of the new link-independent fragmentation support that was introduced in an earlier commit series. This gives a shorter and simpler code path, and makes it possible to obtain copy-free buffer delivery to all node local destination sockets. The new transmission code is added in parallel with the existing one, and will be used by the socket multicast send function in the next commit in this series. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16tipc: let internal link users call the new link send functionJon Paul Maloy
We convert the link internal users (changeover protocol, broadcast synchronization) to use the new packet send function. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16tipc: make name table distributor use new send functionJon Paul Maloy
In a previous commit series ("tipc: new unicast transmission code") we introduced a new message sending function, tipc_link_xmit2(), and moved the unicast data users over to use that function. We now let the internal name table distributor do the same. The interaction between the name distributor and the node/link layer also becomes significantly simpler, so we can eliminate the function tipc_link_names_xmit(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-15tipc: remove unnecessary break after returnFabian Frederick
Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-11tipc: clear 'next'-pointer of message fragments before reassemblyJon Paul Maloy
If the 'next' pointer of the last fragment buffer in a message is not zeroed before reassembly, we risk ending up with a corrupt message, since the reassembly function itself isn't doing this. Currently, when a buffer is retrieved from the deferred queue of the broadcast link, the next pointer is not cleared, with the result as described above. This commit corrects this, and thereby fixes a bug that may occur when long broadcast messages are transmitted across dual interfaces. The bug has been present since 40ba3cdf542a469aaa9083fa041656e59b109b90 ("tipc: message reassembly using fragment chain") 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>
2014-07-08tipc: fix a memleak when sending dataErik Hugne
This fixes a regression bug caused by: 067608e9d019d6477fd45dd948e81af0e5bf599f ("tipc: introduce direct iovec to buffer chain fragmentation function") If data is sent on a nonblocking socket and the destination link is congested, the buffer chain is leaked. We fix this by freeing the chain in this case. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> 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>
2014-07-08tipc: fix bug in multicast/broadcast message reassemblyJon Paul Maloy
Since commit 37e22164a8a3c39bdad45aa463b1e69a1fdf4110 ("tipc: rename and move message reassembly function") reassembly of long broadcast messages has been broken. This is because we test for a non-NULL return value of the *buf parameter as criteria for succesful reassembly. However, this parameter is left defined even after reception of the first fragment, when reassebly is still incomplete. This leads to a kernel crash as soon as a the first fragment of a long broadcast message is received. We fix this with this commit, by implementing a stricter behavior of the function and its return values. This commit should be applied to both net and net-next. 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>
2014-07-07tipc: fix link acknowledge logic in receive pathErik Hugne
Link state acks triggered from the receive path is done before the last received packet have been processed by the link layer. The effect of this is that the last received packet will not be included in the ack. This causes problems if the link window is set to TIPC_MIN_LINK_WIN, where the ack interval will be equal to the link tolerance, and the link enters a stop-and-go behavior. We move the ack logic to after link state processing, just before the packet is delivered to higher layers. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Carl Sigurjonsson <carl.sigurjonsson@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-07tipc: refactor message delivery out of tipc_rcvErik Hugne
This is a cosmetic change, separating message delivery from the link state processing. Signed-off-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>
2014-06-27tipc: simplify connection congestion handlingJon Paul Maloy
As a consequence of the recently introduced serialized access to the socket in commit 8d94168a761819d10252bab1f8de6d7b202c3baa ("tipc: same receive code path for connection protocol and data messages") we can make a number of simplifications in the detection and handling of connection congestion situations. - We don't need to keep two counters, one for sent messages and one for acked messages. There is no longer any risk for races between acknowledge messages arriving in BH and data message sending running in user context. So we merge this into one counter, 'sent_unacked', which is incremented at sending and subtracted from at acknowledge reception. - We don't need to set the 'congested' field in tipc_port to true before we sent the message, and clear it when sending is successful. (As a matter of fact, it was never necessary; the field was set in link_schedule_port() before any wakeup could arrive anyway.) - We keep the conditions for link congestion and connection connection congestion separated. There would otherwise be a risk that an arriving acknowledge message may wake up a user sleeping because of link congestion. - We can simplify reception of acknowledge messages. We also make some cosmetic/structural changes: - We rename the 'congested' field to the more correct 'link_cong´. - We rename 'conn_unacked' to 'rcv_unacked' - We move the above mentioned fields from struct tipc_port to struct tipc_sock. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: clean up connection protocol reception functionJon Paul Maloy
We simplify the code for receiving connection probes, leveraging the recently introduced tipc_msg_reverse() function. We also stick to the principle of sending a possible response message directly from the calling (tipc_sk_rcv or backlog_rcv) functions, hence making the call chain shallower and easier to follow. We make one small protocol change here, allowed according to the spec. If a protocol message arrives from a remote socket that is not the one we are connected to, we are currently generating a connection abort message and send it to the source. This behavior is unnecessary, and might even be a security risk, so instead we now choose to only ignore the message. The consequnce for the sender is that he will need longer time to discover his mistake (until the next timeout), but this is an extreme corner case, and may happen anyway under other circumstances, so we deem this change acceptable. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: same receive code path for connection protocol and data messagesJon Paul Maloy
As a preparation to eliminate port_lock we need to bring reception of connection protocol messages under proper protection of bh_lock_sock or socket owner. We fix this by letting those messages follow the same code path as incoming data messages. As a side effect of this change, the last reference to the function net_route_msg() disappears, and we can eliminate that function. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: let port protocol senders use new link send functionJon Paul Maloy
Several functions in port.c, related to the port protocol and connection shutdown, need to send messages. We now convert them to use the new link send function. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: connection oriented transport uses new send functionsJon Paul Maloy
We move the message sending across established connections to use the message preparation and send functions introduced earlier in this series. We now do the message preparation and call to the link send function directly from the socket, instead of going via the port layer. As a consequence of this change, the functions tipc_send(), tipc_port_iovec_rcv(), tipc_port_iovec_reject() and tipc_reject_msg() become unreferenced and can be eliminated from port.c. For the same reason, the functions tipc_link_xmit_fast(), tipc_link_iovec_xmit_long() and tipc_link_iovec_fast() can be eliminated from link.c. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: RDM/DGRAM transport uses new fragmenting and sending functionsJon Paul Maloy
We merge the code for sending port name and port identity addressed messages into the corresponding send functions in socket.c, and start using the new fragmenting and transmit functions we just have introduced. This saves a call level and quite a few code lines, as well as making this part of the code easier to follow. As a consequence, the functions tipc_send2name() and tipc_send2port() in port.c can be removed. For practical reasons, we break out the code for sending multicast messages from tipc_sendmsg() and move it into a separate function, tipc_sendmcast(), but we do not yet convert it into using the new build/send functions. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: introduce message evaluation functionJon Paul Maloy
When a message arrives in a node and finds no destination socket, we may need to drop it, reject it, or forward it after a secondary destination lookup. The latter two cases currently results in a code path that is perceived as complex, because it follows a deep call chain via obscure functions such as net_route_named_msg() and net_route_msg(). We now introduce a function, tipc_msg_eval(), that takes the decision about whether such a message should be rejected or forwarded, but leaves it to the caller to actually perform the indicated action. If the decision is 'reject', it is still the task of the recently introduced function tipc_msg_reverse() to take the final decision about whether the message is rejectable or not. In the latter case it drops the message. As a result of this change, we can finally eliminate the function net_route_named_msg(), and hence become independent of net_route_msg(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: separate building and sending of rejected messagesJon Paul Maloy
The way we build and send rejected message is currenty perceived as hard to follow, partly because we let the transmission go via deep call chains through functions such as tipc_reject_msg() and net_route_msg(). We want to remove those functions, and make the call sequences shallower and simpler. For this purpose, we separate building and sending of rejected messages. We build the reject message using the new function tipc_msg_reverse(), and let the transmission go via the newly introduced tipc_link_xmit2() function, as all transmission eventually will do. We also ensure that all calls to tipc_link_xmit2() are made outside port_lock/bh_lock_sock. Finally, we replace all calls to tipc_reject_msg() with the two new calls at all locations in the code that we want to keep. The remaining calls are made from code that we are planning to remove, along with tipc_reject_msg() itself. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: introduce direct iovec to buffer chain fragmentation functionJon Paul Maloy
Fragmentation at message sending is currently performed in two places in link.c, depending on whether data to be transmitted is delivered in the form of an iovec or as a big sk_buff. Those functions are also tightly entangled with the send functions that are using them. We now introduce a re-entrant, standalone function, tipc_msg_build2(), that builds a packet chain directly from an iovec. Each fragment is sized according to the MTU value given by the caller, and is prepended with a correctly built fragment header, when needed. The function is independent from who is calling and where the chain will be delivered, as long as the caller is able to indicate a correct MTU. The function is tested, but not called by anybody yet. Since it is incompatible with the existing tipc_msg_build(), and we cannot yet remove that function, we have given it a temporary name. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: make link mtu easily accessible from socketJon Paul Maloy
Message fragmentation is currently performed at link level, inside the protection of node_lock. This potentially binds up the sending link structure for a long time, instead of letting it do other tasks, such as handle reception of new packets. In this commit, we make the MTUs of each active link become easily accessible from the socket level, i.e., without taking any spinlock or dereferencing the target link pointer. This way, we make it possible to perform fragmentation in the sending socket, before sending the whole fragment chain to the link for transport. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: introduce send functions for chained buffers in linkJon Paul Maloy
The current link implementation provides several different transmit functions, depending on the characteristics of the message to be sent: if it is an iovec or an sk_buff, if it needs fragmentation or not, if the caller holds the node_lock or not. The permutation of these options gives us an unwanted amount of unnecessarily complex code. As a first step towards simplifying the send path for all messages, we introduce two new send functions at link level, tipc_link_xmit2() and __tipc_link_xmit2(). The former looks up a link to the message destination, and if one is found, it grabs the node lock and calls the second function, which works exclusively inside the node lock protection. If no link is found, and the destination is on the same node, it delivers the message directly to the local destination socket. The new functions take a buffer chain where all packet headers are already prepared, and the correct MTU has been used. These two functions will later replace all other link-level transmit functions. The functions are not backwards compatible, so we have added them as new functions with temporary names. They are tested, but have no users yet. Those will be added later in this series. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27tipc: use negative error return values in functionsJon Paul Maloy
In some places, TIPC functions returns positive integers as return codes. This goes against standard Linux coding practice, and may even cause problems in some cases. We now change the return values of the functions filter_rcv() and filter_connect() to become signed integers, and return negative error codes when needed. The codes we use in these particular cases are still TIPC specific, since they are both part of the TIPC API and have no correspondence in errno.h Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>