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2015-07-30tipc: move received discovery data evaluation inside node.cJon Paul Maloy
The node lock is currently grabbed and and released in the function tipc_disc_rcv() in the file discover.c. As a preparation for the next commits, we need to move this node lock handling, along with the code area it is covering, to node.c. This commit introduces this change. Tested-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>
2015-07-20tipc: move link creation from neighbor discoverer to nodeJon Paul Maloy
As a step towards turning links into node internal entities, we move the creation of links from the neighbor discovery logics to the node's link control logics. We also create an additional entry for the link's media address in the newly introduced struct tipc_link_entry, since this is where it is needed in the upcoming commits. The current copy in struct tipc_link is kept for now, but will be removed later. 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>
2015-07-20tipc: introduce link entry structure to struct tipc_nodeJon Paul Maloy
struct 'tipc_node' currently contains two arrays for link attributes, one for the link pointers, and one for the usable link MTUs. We now group those into a new struct 'tipc_link_entry', and intoduce one single array consisting of such enties. Apart from being a cosmetic improvement, this is a starting point for the strict master-slave relation between node and link that we will introduce in the following commits. 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>
2015-03-29tipc: involve reference counter for node structureYing Xue
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>
2015-03-14tipc: add framework for node capabilities exchangeJon Paul Maloy
The TIPC protocol spec has defined a 13 bit capability bitmap in the neighbor discovery header, as a means to maintain compatibility between different code and protocol generations. Until now this field has been unused. We now introduce the basic framework for exchanging capabilities between nodes at first contact. After exchange, a peer node's capabilities are stored as a 16 bit bitmap in struct tipc_node. 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>
2015-03-05tipc: increase size of tipc discovery messagesErik Hugne
The payload area following the TIPC discovery message header is an opaque area defined by the media. INT_H_SIZE was enough for Ethernet/IB/IPv4 but needs to be expanded to carry IPv6 addressing information. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05tipc: reduce usage of context info in socket and linkJon Paul Maloy
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>
2015-02-04tipc: eliminate race during node creationJon Paul Maloy
Instances of struct node are created in the function tipc_disc_rcv() under the assumption that there is no race between received discovery messages arriving from the same node. This assumption is wrong. When we use more than one bearer, it is possible that discovery messages from the same node arrive at the same moment, resulting in creation of two instances of struct tipc_node. This may later cause confusion during link establishment, and may result in one of the links never becoming activated. We fix this by making lookup and potential creation of nodes atomic. Instead of first looking up the node, and in case of failure, create it, we now start with looking up the node inside node_link_create(), and return a reference to that one if found. Otherwise, we go ahead and create the node as we did before. 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>
2015-01-12tipc: make tipc random value aware of net namespaceYing Xue
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>
2015-01-12tipc: make tipc node address support net namespaceYing Xue
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>
2015-01-12tipc: make bearer list support net namespaceYing Xue
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>
2015-01-12tipc: make tipc node table aware of net namespaceYing Xue
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>
2015-01-12tipc: involve namespace infrastructureYing Xue
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>
2015-01-12tipc: remove unnecessary wrapper functions of kernel timer APIsYing Xue
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>
2014-05-14tipc: clean up neigbor discovery message receptionJon Paul Maloy
The function tipc_disc_rcv(), which is handling received neighbor discovery messages, is perceived as messy, and it is hard to verify its correctness by code inspection. The fact that the task it is set to resolve is fairly complex does not make the situation better. In this commit we try to take a more systematic approach to the problem. We define a decision machine which takes three state flags as input, and produces three action flags as output. We then walk through all permutations of the state flags, and for each of them we describe verbally what is going on, plus that we set zero or more of the action flags. The action flags indicate what should be done once the decision machine has finished its job, while the last part of the function deals with performing those actions. 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>
2014-05-14tipc: improve and extend media address conversion functionsJon Paul Maloy
TIPC currently handles two media specific addresses: Ethernet MAC addresses and InfiniBand addresses. Those are kept in three different formats: 1) A "raw" format as obtained from the device. This format is known only by the media specific adapter code in eth_media.c and ib_media.c. 2) A "generic" internal format, in the form of struct tipc_media_addr, which can be referenced and passed around by the generic media- unaware code. 3) A serialized version of the latter, to be conveyed in neighbor discovery messages. Conversion between the three formats can only be done by the media specific code, so we have function pointers for this purpose in struct tipc_media. Here, the media adapters can install their own conversion functions at startup. We now introduce a new such function, 'raw2addr()', whose purpose is to convert from format 1 to format 2 above. We also try to as far as possible uniform commenting, variable names and usage of these functions, with the purpose of making them more comprehensible. We can now also remove the function tipc_l2_media_addr_set(), whose job is done better by the new function. Finally, we expand the field for serialized addresses (format 3) in discovery messages from 20 to 32 bytes. This is permitted according to the spec, and reduces the risk of problems when we add new media in the future. 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>
2014-04-27tipc: fix a possible memory leakYing Xue
The commit a8b9b96e959f3c035af20b1bd2ba67b0b7269b19 ("tipc: fix race in disc create/delete") leads to the following static checker warning: net/tipc/discover.c:352 tipc_disc_create() warn: possible memory leak of 'req' The risk of memory leak really exists in practice. Especially when it's failed to allocate memory for "req->buf", tipc_disc_create() doesn't free its allocated memory, instead just directly returns with ENOMEM error code. In this situation, memory leak, of course, happens. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22tipc: fix race in disc create/deleteYing Xue
Commit a21a584d6720ce349b05795b9bcfab3de8e58419 (tipc: fix neighbor detection problem after hw address change) introduces a race condition involving tipc_disc_delete() and tipc_disc_add/remove_dest that can cause TIPC to dereference the pointer to the bearer discovery request structure after it has been freed since a stray pointer is left in the bearer structure. In order to fix the issue, the process of resetting the discovery request handler is optimized: the discovery request handler and request buffer are just reset instead of being freed, allocated and initialized. As the request point is always valid and the request's lock is taken while the request handler is reset, the race doesn't happen any more. Reported-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Tested-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22tipc: decouple the relationship between bearer and linkYing Xue
Currently on both paths of message transmission and reception, the read lock of tipc_net_lock must be held before bearer is accessed, while the write lock of tipc_net_lock has to be taken before bearer is configured. Although it can ensure that bearer is always valid on the two data paths, link and bearer is closely bound together. So as the part of effort of removing tipc_net_lock, the locking policy of bearer protection will be adjusted as below: on the two data paths, RCU is used, and on the configuration path of bearer, RTNL lock is applied. Now RCU just covers the path of message reception. To make it possible to protect the path of message transmission with RCU, link should not use its stored bearer pointer to access bearer, but it should use the bearer identity of its attached bearer as index to get bearer instance from bearer_list array, which can help us decouple the relationship between bearer and link. As a result, bearer on the path of message transmission can be safely protected by RCU when we access bearer_list array within RCU lock protection. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Tested-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-28tipc: make discovery domain a bearer attributeErik Hugne
The node discovery domain is assigned when a bearer is enabled. In the previous commit we reflect this attribute directly in the bearer structure since it's needed to reinitialize the node discovery mechanism after a hardware address change. There's no need to replicate this attribute anywhere else, so we remove it from the tipc_link_req structure. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-18tipc: align tipc function names with common naming practice in the networkYing Xue
Rename the following functions, which are shorter and more in line with common naming practice in the network subsystem. tipc_bclink_send_msg->tipc_bclink_xmit tipc_bclink_recv_pkt->tipc_bclink_rcv tipc_disc_recv_msg->tipc_disc_rcv tipc_link_send_proto_msg->tipc_link_proto_xmit link_recv_proto_msg->tipc_link_proto_rcv link_send_sections_long->tipc_link_iovec_long_xmit tipc_link_send_sections_fast->tipc_link_iovec_xmit_fast tipc_link_send_sync->tipc_link_sync_xmit tipc_link_recv_sync->tipc_link_sync_rcv tipc_link_send_buf->__tipc_link_xmit tipc_link_send->tipc_link_xmit tipc_link_send_names->tipc_link_names_xmit tipc_named_recv->tipc_named_rcv tipc_link_recv_bundle->tipc_link_bundle_rcv tipc_link_dup_send_queue->tipc_link_dup_queue_xmit link_send_long_buf->tipc_link_frag_xmit tipc_multicast->tipc_port_mcast_xmit tipc_port_recv_mcast->tipc_port_mcast_rcv tipc_port_reject_sections->tipc_port_iovec_reject tipc_port_recv_proto_msg->tipc_port_proto_rcv tipc_connect->tipc_port_connect __tipc_connect->__tipc_port_connect __tipc_disconnect->__tipc_port_disconnect tipc_disconnect->tipc_port_disconnect tipc_shutdown->tipc_port_shutdown tipc_port_recv_msg->tipc_port_rcv tipc_port_recv_sections->tipc_port_iovec_rcv release->tipc_release accept->tipc_accept bind->tipc_bind get_name->tipc_getname poll->tipc_poll send_msg->tipc_sendmsg send_packet->tipc_send_packet send_stream->tipc_send_stream recv_msg->tipc_recvmsg recv_stream->tipc_recv_stream connect->tipc_connect listen->tipc_listen shutdown->tipc_shutdown setsockopt->tipc_setsockopt getsockopt->tipc_getsockopt Above changes have no impact on current users of the functions. 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>
2014-01-07tipc: introduce new spinlock to protect struct link_reqYing Xue
Currently, only 'bearer_lock' is used to protect struct link_req in the function disc_timeout(). This is unsafe, since the member fields 'num_nodes' and 'timer_intv' might be accessed by below three different threads simultaneously, none of them grabbing bearer_lock in the critical region: link_activate() tipc_bearer_add_dest() tipc_disc_add_dest() req->num_nodes++; tipc_link_reset() tipc_bearer_remove_dest() tipc_disc_remove_dest() req->num_nodes-- disc_update() read req->num_nodes write req->timer_intv disc_timeout() read req->num_nodes read/write req->timer_intv Without lock protection, the only symptom of a race is that discovery messages occasionally may not be sent out. This is not fatal, since such messages are best-effort anyway. On the other hand, since discovery messages are not time critical, adding a protecting lock brings no serious overhead either. So we add a new, dedicated spinlock in order to guarantee absolute data consistency in link_req objects. This also helps reduce the overall role of the bearer_lock, which we want to remove completely in a later commit series. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09tipc: remove interface state mirroring in bearerErik Hugne
struct 'tipc_bearer' is a generic representation of the underlying media type, and exists in a one-to-one relationship to each interface TIPC is using. The struct contains a 'blocked' flag that mirrors the operational and execution state of the represented interface, and is updated through notification calls from the latter. The users of tipc_bearer are checking this flag before each attempt to send a packet via the interface. This state mirroring serves no purpose in the current code base. TIPC links will not discover a media failure any faster through this mechanism, and in reality the flag only adds overhead at packet sending and reception. Furthermore, the fact that the flag needs to be protected by a spinlock aggregated into tipc_bearer has turned out to cause a serious and completely unnecessary deadlock problem. CPU0 CPU1 ---- ---- Time 0: bearer_disable() link_timeout() Time 1: spin_lock_bh(&b_ptr->lock) tipc_link_push_queue() Time 2: tipc_link_delete() tipc_bearer_blocked(b_ptr) Time 3: k_cancel_timer(&req->timer) spin_lock_bh(&b_ptr->lock) Time 4: del_timer_sync(&req->timer) I.e., del_timer_sync() on CPU0 never returns, because the timer handler on CPU1 is waiting for the bearer lock. We eliminate the 'blocked' flag from struct tipc_bearer, along with all tests on this flag. This not only resolves the deadlock, but also simplifies and speeds up the data path execution of TIPC. It also fits well into our ongoing effort to make the locking policy simpler and more manageable. An effect of this change is that we can get rid of functions such as tipc_bearer_blocked(), tipc_continue() and tipc_block_bearer(). We replace the latter with a new function, tipc_reset_bearer(), which resets all links associated to the bearer immediately after an interface goes down. A user might notice one slight change in link behaviour after this change. When an interface goes down, (e.g. through a NETDEV_DOWN event) all attached links will be reset immediately, instead of leaving it to each link to detect the failure through a timer-driven mechanism. We consider this an improvement, and see no obvious risks with the new behavior. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <Paul.Gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17tipc: cosmetic realignment of function argumentsPaul Gortmaker
No runtime code changes here. Just a realign of the function arguments to start where the 1st one was, and fit as many args as can be put in an 80 char line. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17tipc: move bcast_addr from struct tipc_media to struct tipc_bearerPatrick McHardy
Some network protocols, like InfiniBand, don't have a fixed broadcast address but one that depends on the configuration. Move the bcast_addr to struct tipc_bearer and initialize it with the broadcast address of the network device when the bearer is enabled. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-21tipc: remove the bearer congestion mechanismYing Xue
Currently at the TIPC bearer layer there is the following congestion mechanism: Once sending packets has failed via that bearer, the bearer will be flagged as being in congested state at once. During bearer congestion, all packets arriving at link will be queued on the link's outgoing buffer. When we detect that the state of bearer congestion has relaxed (e.g. some packets are received from the bearer) we will try our best to push all packets in the link's outgoing buffer until the buffer is empty, or until the bearer is congested again. However, in fact the TIPC bearer never receives any feedback from the device layer whether a send was successful or not, so it must always assume it was successful. Therefore, the bearer congestion mechanism as it exists currently is of no value. But the bearer blocking state is still useful for us. For example, when the physical media goes down/up, we need to change the state of the links bound to the bearer. So the code maintaing the state information is not removed. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-07-13tipc: phase out most of the struct print_buf usageErik Hugne
The tipc_printf is renamed to tipc_snprintf, as the new name describes more what the function actually does. It is also changed to take a buffer and length parameter and return number of characters written to the buffer. All callers of this function that used to pass a print_buf are updated. Final removal of the struct print_buf itself will be done synchronously with the pending removal of the deprecated logging code that also was using it. Functions that build up a response message with a list of ports, nametable contents etc. are changed to return the number of characters written to the output buffer. This information was previously hidden in a field of the print_buf struct, and the number of chars written was fetched with a call to tipc_printbuf_validate. This function is removed since it is no longer referenced nor needed. A generic max size ULTRA_STRING_MAX_LEN is defined, named in keeping with the existing TIPC_TLV_ULTRA_STRING, and the various definitions in port, link and nametable code that largely duplicated this information are removed. This means that amount of link statistics that can be returned is now increased from 2k to 32k. The buffer overflow check is now done just before the reply message is passed over netlink or TIPC to a remote node and the message indicating a truncated buffer is changed to a less dramatic one (less CAPS), placed at the end of the message. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-07-13tipc: use standard printk shortcut macros (pr_err etc.)Erik Hugne
All messages should go directly to the kernel log. The TIPC specific error, warning, info and debug trace macro's are removed and all references replaced with pr_err, pr_warn, pr_info and pr_debug. Commonly used sub-strings are explicitly declared as a const char to reduce .text size. Note that this means the debug messages (changed to pr_debug), are now enabled through dynamic debugging, instead of a TIPC specific Kconfig option (TIPC_DEBUG). The latter will be phased out completely Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> [PG: use pr_fmt as suggested by Joe Perches <joe@perches.com>] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-04-30tipc: compress out gratuitous extra carriage returnsPaul Gortmaker
Some of the comment blocks are floating in limbo between two functions, or between blocks of code. Delete the extra line feeds between any comment and its associated following block of code, to be consistent with the majority of the rest of the kernel. Also delete trailing newlines at EOF and fix a couple trivial typos in existing comments. This is a 100% cosmetic change with no runtime impact. We get rid of over 500 lines of non-code, and being blank line deletes, they won't even show up as noise in git blame. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24tipc: Eliminate trivial buffer manipulation helper routinesAllan Stephens
Gets rid of two inlined routines that simply call existing sk_buff manipulation routines, since there is no longer any extra processing done by the helper routines. Note that these changes are essentially cosmetic in nature, and have no impact on the actual operation of TIPC. Signed-off-by: Allan Stephens <allan.stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24tipc: Detect duplicate nodes using different network interfacesAllan Stephens
Utilizes the new "node signature" field in neighbor discovery messages to ensure that all links TIPC associates with a given <Z.C.N> network address belong to the same neighboring node. (Previously, TIPC could not tell if link setup requests arriving on different interfaces were from the same node or from two different nodes that has mistakenly been assigned the same network address.) The revised algorithm for detecting a duplicate node considers both the node signature and the network interface adddress specified in a request message when deciding how to respond to a link setup request. This prevents false alarms that might otherwise arise during normal network operation under the following scenarios: a) A neighboring node reboots. (The node's signature changes, but the network interface address remains unchanged.) b) A neighboring node's network interface is replaced. (The node's signature remains unchanged, but the network interface address changes.) c) A neighboring node is completely replaced. (The node's signature and network interface address both change.) The algorithm also handles cases in which a node reboots and re-establishes its links to TIPC (or begins re-establishing those links) before TIPC detects that it is using a new node signature. In such cases of "delayed rediscovery" TIPC simply accepts the new signature without disrupting communication that is already underway over the links. Thanks to Laser [gotolaser@gmail.com] for his contributions to the development of this enhancement. Signed-off-by: Allan Stephens <allan.stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24tipc: Introduce node signature field in neighbor discovery messageAllan Stephens
Adds support for the new "node signature" in neighbor discovery messages, which is a 16 bit identifier chosen randomly when TIPC is initialized. This field makes it possible for nodes receiving a neighbor discovery message to detect if multiple neighboring nodes are using the same network address (i.e. <Z.C.N>), even when the messages are arriving on different interfaces. This first phase of node signature support creates the signature, incorporates it into outgoing neighbor discovery messages, and tracks the signature used by valid neighbors. An upcoming patch builds on this foundation to implement the improved duplicate neighbor detection checking. Signed-off-by: Allan Stephens <allan.stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-29tipc: rename struct link* to struct tipc_link*Paul Gortmaker
This converts the following: struct link -> struct tipc_link struct link_req -> struct tipc_link_req struct link_name -> struct tipc_link_name Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-27tipc: Ignore neighbor discovery messages containing invalid addressAllan Stephens
Adds a check to ensure that TIPC ignores an incoming neighbor discovery message that specifies an invalid media address as its source. The check ensures that the source address is a valid, non-broadcast address that could legally be used by a neighboring link endpoint. Signed-off-by: Allan Stephens <allan.stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-27tipc: Hide media-specific addressing details from generic bearer codeAllan Stephens
Reworks TIPC's media address data structure and associated processing routines to transfer all media-specific details of address conversion to the associated TIPC media adaptation code. TIPC's generic bearer code now only needs to know which media type an address is associated with and whether or not it is a broadcast address, and totally ignores the "value" field that contains the actual media-specific addressing info. These changes eliminate the need for a number of endianness conversion operations and will make it easier for TIPC to support new media types in the future. Signed-off-by: Allan Stephens <allan.stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-09-17tipc: Ensure both nodes recognize loss of contact between themAllan Stephens
Enhances TIPC to ensure that a node that loses contact with a neighboring node does not allow contact to be re-established until it sees that its peer has also recognized the loss of contact. Previously, nodes that were connected by two or more links could encounter a situation in which node A would lose contact with node B on all of its links, purge its name table of names published by B, and then fail to repopulate those names once contact with B was restored. This would happen because B was able to re-establish one or more links so quickly that it never reached a point where it had no links to A -- meaning that B never saw a loss of contact with A, and consequently didn't re-publish its names to A. This problem is now prevented by enhancing the cleanup done by TIPC following a loss of contact with a neighboring node to ensure that node A ignores all messages sent by B until it receives a LINK_PROTOCOL message that indicates B has lost contact with A, thereby preventing the (re)establishment of links between the nodes. The loss of contact is recognized when a RESET or ACTIVATE message is received that has a "redundant link exists" field of 0, indicating that B's sending link endpoint is in a reset state and that B has no other working links. Additionally, TIPC now suppresses the sending of (most) link protocol messages to a neighboring node while it is cleaning up after an earlier loss of contact with that node. This stops the peer node from prematurely activating its link endpoint, which would prevent TIPC from later activating its own end. TIPC still allows outgoing RESET messages to occur during cleanup, to avoid problems if its own node recognizes the loss of contact first and tries to notify the peer of the situation. Finally, TIPC now recognizes an impending loss of contact with a peer node as soon as it receives a RESET message on a working link that is the peer's only link to the node, and ensures that the link protocol suppression mentioned above goes into effect right away -- that is, even before its own link endpoints have failed. This is necessary to ensure correct operation when there are redundant links between the nodes, since otherwise TIPC would send an ACTIVATE message upon receiving a RESET on its first link and only begin suppressing when a RESET on its second link was received, instead of initiating suppression with the first RESET message as it needs to. Note: The reworked cleanup code also eliminates a check that prevented a link endpoint's discovery object from responding to incoming messages while stale name table entries are being purged. This check is now unnecessary and would have slowed down re-establishment of communication between the nodes in some situations. Signed-off-by: Allan Stephens <allan.stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10tipc: Revise timings used when sending link request messagesAllan Stephens
Revises the algorithm governing the sending of link request messages to take into account the number of nodes each bearer is currently in contact with, and to ensure more rapid rediscovery of neighboring nodes if a bearer fails and then recovers. The discovery object now sends requests at least once a second if it is not in contact with any other nodes, and at least once a minute if it has at least one neighbor; if contact with the only neighbor is lost, the object immediately reverts to its initial rapid-fire search timing to accelerate the rediscovery process. In addition, the discovery object now stops issuing link request messages if it is in contact with the only neighboring node it is configured to communicate with, since further searching is unnecessary. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10tipc: Add monitoring of number of nodes discovered by bearerAllan Stephens
Augments TIPC's discovery object to track the number of neighboring nodes having an active link to the associated bearer. This means tipc_disc_update_link_req() becomes either one of: tipc_disc_add_dest() or: tipc_disc_remove_dest() depending on the code flow direction of things. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10tipc: Enhance sending of discovery object link request messagesAllan Stephens
Augments TIPC's discovery object to send its initial neighbor discovery request message as soon as the associated bearer is created, rather than waiting for its first periodic timeout to occur, thereby speeding up the discovery process. Also adds a check to suppress the initial request or subsequent requests if the bearer is blocked at the time the request is scheduled for transmission. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10tipc: Enhance handling of discovery object creation failuresAllan Stephens
Modifies bearer creation and deletion code to improve handling of scenarios when a neighbor discovery object cannot be created. The creation routine now aborts the creation of a bearer if its discovery object cannot be created, and deletes the newly created bearer, rather than failing quietly and leaving an unusable bearer hanging around. Since the exit via the goto label really isn't a definitive failure in all cases, relabel it appropriately. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10tipc: Strengthen checks for neighboring node discoveryAllan Stephens
Enhances existing checks on the discovery domain associated with a TIPC bearer. A bearer can no longer be configured to accept links from itself only (which would be pointless), or to nodes outside its own cluster (since multi-cluster support has now been removed from TIPC). Also, the neighbor discovery routine now validates link setup requests against the configured discovery domain for the bearer, rather than simply ensuring the requesting node belongs to the node's own cluster. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13tipc: Don't respond to neighbor discovery request on blocked bearerAllan Stephens
Adds a check to prevent TIPC from trying to respond to an incoming LINK_CONFIG request message if the associated bearer is currently prohibited from sending messages. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13tipc: Eliminate unnecessary constant for neighbor discovery msg sizeAllan Stephens
Eliminates an unnecessary constant that defines the size of a LINK_CONFIG message, and uses one of the existing standard message size symbols in its place. (The defunct constant was located in the wrong place anyway, since it was grouped with other constants that define message users instead of message sizes.) Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13tipc: Optimizations to link creation codeAllan Stephens
Enhances link creation code as follows: 1) Detects illegal attempts to add a requested link earlier in the link creation process. This prevents TIPC from wasting time initializing a link object it then throws away, and also eliminates the code needed to do the throwing away. 2) Passes in the node object associated with the requested link. This allows TIPC to eliminate a search to locate the node object, as well as code that attempted to create the node if it doesn't exist. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13tipc: Give Tx of discovery responses priority over link messagesAllan Stephens
Delay releasing the node lock when processing a neighbor discovery message until after the optional discovery response message has been sent. This helps ensure that any link protocol messages sent by a link endpoint created as a result of a neighbor discovery request are received after the discovery response is received, thereby giving the receiving node a chance to create a peer link endpoint to consume those link protocol messages, if one does not already exist. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13tipc: Cosmetic changes to neighbor discovery logicAllan Stephens
Reworks the appearance of the routine that processes incoming LINK_CONFIG messages to keep the main logic flow at a consistent level of indentation, and to add comments outlining the various phases involved in processing each message. This rework is being done to allow upcoming enhancements to this routine to be integrated more cleanly. The diff isn't really readable, so know that it was a case of the old code being like: tipc_disc_recv_msg(..) { if (in_own_cluster(orig)) { ... lines and lines of stuff ... } } which is now replaced with the more sane: tipc_disc_recv_msg(..) { if (!in_own_cluster(orig)) return; ... lines and lines of stuff ... } Instances of spin locking within the reindented block were replaced with the identical tipc_node_[un]lock() abstractions. Note that all these changes are cosmetic in nature, and do not change the way LINK_CONFIG messages are processed. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-02-23tipc: Remove unused message header field for requested number of linksAllan Stephens
Eliminates support for the "number of requested links" field in a neighbor discovery message. This field was never used and has been removed from the TIPC 2.0 protocol specification. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-02-23tipc: Combine bearer structure with tipc_bearer structureAllan Stephens
Combines two distinct structures containing information about a TIPC bearer into a single structure. The structures were previously kept separate so that public information about a bearer could be made available to plug-in media types using TIPC's native API, while the remaining information was kept private for use by TIPC itself. However, now that the native API has been removed there is no longer any need for this arrangement. Since one of the structures was already embedded within the other, the change largely involves replacing instances of "publ.foo" with "foo". The changes do not otherwise alter the operation of TIPC bearers. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-01-01tipc: cleanup various cosmetic whitespace issuesAllan Stephens
Cleans up TIPC's source code to eliminate deviations from generally accepted coding conventions relating to leading/trailing white space and white space around commas, braces, cases, and sizeof. These changes are purely cosmetic and do not alter the operation of TIPC in any way. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-01tipc: remove redundant #includesAllan Stephens
Eliminates a number of #include statements that no longer serve any useful purpose. Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>