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* tipc: tipc: convert node list and node hlist to RCU listsYing Xue2014-03-27
| | | | | | | | | | | Convert tipc_node_list list and node_htable hash list to RCU lists. On read side, the two lists are protected with RCU read lock, and on update side, node_list_lock is applied to them. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: remove active flag from tipc_bearer structureYing Xue2014-03-27
| | | | | | | | | | | | | After the allocation of tipc_bearer structure instance is converted from statical way to dynamical way, we identify whether a certain tipc_bearer structure pointer is valid by checking whether the pointer is NULL or not. So the active flag in tipc_bearer structure becomes redundant. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: eliminate upcall function pointers between port and socketJon Paul Maloy2014-03-12
| | | | | | | | | | | | | | | | | | | | Due to the original one-to-many relation between port and user API layers, upcalls to the API have been performed via function pointers, installed in struct tipc_port at creation. Since this relation now always is one-to-one, we can instead use ordinary function calls. We remove the function pointers 'dispatcher' and ´wakeup' from struct tipc_port, and replace them with calls to the renamed functions tipc_sk_rcv() and tipc_sk_wakeup(). At the same time we change the name and signature of the functions tipc_createport() and tipc_deleteport() to reflect their new role as mere initialization/destruction functions. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: failed transmissions should return errorErik Hugne2014-02-19
| | | | | | | | | | | | | | | | | | When a message could not be sent out because the destination node or link could not be found, the full message size is returned from sendmsg() as if it had been sent successfully. An application will then get a false indication that it's making forward progress. This problem has existed since the initial commit in 2.6.16. We change this to return -ENETUNREACH if the message cannot be delivered due to the destination node/link being unavailable. We also get rid of the redundant tipc_reject_msg call since freeing the buffer and doing a tipc_port_iovec_reject accomplishes exactly the same thing. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2014-02-19
|\ | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/bonding/bond_3ad.h drivers/net/bonding/bond_main.c Two minor conflicts in bonding, both of which were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * tipc: fix message corruption bug for deferred packetsErik Hugne2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a packet received on a link is out-of-sequence, it will be placed on a deferred queue and later reinserted in the receive path once the preceding packets have been processed. The problem with this is that it will be subject to the buffer adjustment from link_recv_buf_validate twice. The second adjustment for 20 bytes header space will corrupt the packet. We solve this by tagging the deferred packets and bail out from receive buffer validation for packets that have already been subjected to this. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: align tipc function names with common naming practice in the networkYing Xue2014-02-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | tipc: correct usage of spin_lock() vs spin_lock_bh()Jon Paul Maloy2014-02-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I commit e099e86c9e24fe9aff36773600543eb31d8954d ("tipc: add node_lock protection to link lookup function") we are calling spin_lock(&node->lock) directly instead of indirectly via the tipc_node_lock(node) function. However, tipc_node_lock() is using spin_lock_bh(), not spin_lock(), something leading to unbalanced usage in one place, and a smatch warning. We fix this by consistently using tipc_node_lock()/unlock() in in the places touched by the mentioned commit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: add node_lock protection to link lookup functionJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In an earlier commit, ("tipc: remove links list from bearer struct") we described three issues that need to be pre-emptively resolved before we can remove tipc_net_lock. Here we resolve issue a) described in that commit: "a) In access method #2, we access the link before taking the protecting node_lock. This will not work once net_lock is gone, so we will have to change the access order. We will deal with this in a later commit in this series." Here, we change that access order, by ensuring that the function link_find_link() returns only a safe reference for finding the link, i.e., a node pointer and an index into its 'links' array, not the link pointer itself. We also change all callers of this function to first take the node lock before they can check if there still is a valid link pointer at the returned index. Since the function now returns a node pointer rather than a link pointer, we rename it to the more appropriate 'tipc_link_find_owner(). 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>
* | tipc: delay delete of link when failover is neededJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a bearer is disabled, all its attached links are deleted. Ideally, we should do link failover to redundant links on other bearers, if there are any, in such cases. This would be consistent with current behavior when a link is reset, but not deleted. However, due to the complexity involved, and the (wrongly) perceived low demand for this feature, it was never implemented until now. We mark the doomed link for deletion with a new flag, but wait until the failover process is finished before we actually delete it. With the improved link tunnelling/failover code introduced earlier in this commit series, it is now easy to identify a spot in the code where the failover is finished and it is safe to delete the marked link. Moreover, the test for the flag and the deletion can be done synchronously, and outside the most time critical data path. 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>
* | tipc: changes to general packet reception algorithmJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We change the order of checking for destination users when processing incoming packets. By placing the checks for users that may potentially replace the processed buffer, i.e., CHANGEOVER_PROTOCOL and MSG_FRAGMENTER, in a separate step before we check for the true end users, we get rid of a label and a 'goto', at the same time making the code more comprehensible and easy to follow. This commit does not change any functionality, it is just a cosmetic code reshuffle. 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>
* | tipc: rename stack variables in function tipc_link_tunnel_rcvJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | After the previous redesign of the tunnel reception algorithm and functions, we finalize it by renaming a couple of stack variables in tipc_tunnel_rcv(). This makes it more consistent with the naming scheme elsewhere in this part of the code. This change is purely cosmetic, with no functional changes. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: more cleanup of tunnelling reception functionJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | We simplify and slim down the code in function tipc_tunnel_rcv() No impact on the users of this function. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: change signature of tunnelling reception functionJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After the earlier commits in this series related to the function tipc_link_tunnel_rcv(), we can now go further and simplify its signature. The function now consumes all DUPLICATE packets, and only returns such ORIGINAL packets that are ready for immediate delivery, i.e., no more link level protocol processing needs to be done by the caller. As a consequence, the the caller, tipc_rcv(), does not access the link pointer after call return, and it becomes unnecessary to pass a link pointer reference in the call. Instead, we now only pass it the tunnel link's owner node, which is sufficient to find the destination link for the tunnelled packet. 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>
* | tipc: change reception of tunnelled failover packetsJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a link is reset, and there is a redundant link available, all sender sockets will steer their subsequent traffic through the remaining link. In order to guarantee preserved packet order and cardinality during the transition, we tunnel the failing link's send queue through the remaining link before we allow any sockets to use it. In this commit, we change the algorithm for receiving failover ("ORIGINAL_MSG") packets in tipc_link_tunnel_rcv(), at the same time delegating it to a new subfuncton, tipc_link_failover_rcv(). Instead of directly returning an extracted inner packet to the packet reception loop in tipc_rcv(), we first check if it is a message fragment, in which case we append it to the reset link's fragment chain. If the fragment chain is complete, we return the whole chain instead of the individual buffer, eliminating any need for the tipc_rcv() loop to do reassembly of tunneled packets. This change makes it possible to further simplify tipc_link_tunnel_rcv(), as well as the calling tipc_rcv() loop. We will do that in later commits. It also makes it possible to identify a single spot in the code where we can tell that a failover procedure is finished, something that is useful when we are deleting links after a failover. This will also be done in a later commit. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: change reception of tunnelled duplicate packetsJon Paul Maloy2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a second link to a destination comes up, some sender sockets will steer their subsequent traffic through the new link. In order to guarantee preserved packet order and cardinality for those sockets, we tunnel a duplicate of the old link's send queue through the new link before we open it for regular traffic. The last arriving packet copy, on whichever link, will be dropped at the receiving end based on the original sequence number, to ensure that only one copy is delivered to the end receiver. In this commit, we change the algorithm for receiving DUPLICATE_MSG packets, at the same time delegating it to a new subfunction, tipc_link_dup_rcv(). Instead of returning an extracted inner packet to the packet reception loop in tipc_rcv(), we just add it to the receiving (new) link's deferred packet queue. The packet will then be processed by that link when it receives its first non-tunneled packet, i.e., at latest when the changeover procedure is finished. Because tipc_link_tunnel_rcv()/tipc_link_dup_rcv() now is consuming all packets of type DUPLICATE_MSG, the calling tipc_rcv() function can omit testing for this. This in turn means that the current conditional jump to the label 'protocol_check' becomes redundant, and we can remove that label. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: remove 'links' list from tipc_bearer structYing Xue2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In our ongoing effort to simplify the TIPC locking structure, we see a need to remove the linked list for tipc_links in the bearer. This can be explained as follows. Currently, we have three different ways to access a link, via three different lists/tables: 1: Via a node hash table: Used by the time-critical outgoing/incoming data paths. (e.g. link_send_sections_fast() and tipc_recv_msg() ): grab net_lock(read) find node from node hash table grab node_lock select link grab bearer_lock send_msg() release bearer_lock release node lock release net_lock 2: Via a global linked list for nodes: Used by configuration commands (link_cmd_set_value()) grab net_lock(read) find node and link from global node list (using link name) grab node_lock update link release node lock release net_lock (Same locking order as above. No problem.) 3: Via the bearer's linked link list: Used by notifications from interface (e.g. tipc_disable_bearer() ) grab net_lock(write) grab bearer_lock get link ptr from bearer's link list get node from link grab node_lock delete link release node lock release bearer_lock release net_lock (Different order from above, but works because we grab the outer net_lock in write mode first, excluding all other access.) The first major goal in our simplification effort is to get rid of the "big" net_lock, replacing it with rcu-locks when accessing the node list and node hash array. This will come in a later patch series. But to get there we first need to rewrite access methods ##2 and 3, since removal of net_lock would introduce three major problems: a) In access method #2, we access the link before taking the protecting node_lock. This will not work once net_lock is gone, so we will have to change the access order. We will deal with this in a later commit in this series, "tipc: add node lock protection to link found by link_find_link()". b) When the outer protection from net_lock is gone, taking bearer_lock and node_lock in opposite order of method 1) and 2) will become an obvious deadlock hazard. This is fixed in the commit ("tipc: remove bearer_lock from tipc_bearer struct") later in this series. c) Similar to what is described in problem a), access method #3 starts with using a link pointer that is unprotected by node_lock, in order to via that pointer find the correct node struct and lock it. Before we remove net_lock, this access order must be altered. This is what we do with this commit. We can avoid introducing problem problem c) by even here using the global node list to find the node, before accessing its links. When we loop though the node list we use the own bearer identity as search criteria, thus easily finding the links that are associated to the resetting/disabling bearer. It should be noted that although this method is somewhat slower than the current list traversal, it is in no way time critical. This is only about resetting or deleting links, something that must be considered relatively infrequent events. As a bonus, we can get rid of the mutual pointers between links and bearers. After this commit, pointer dependency go in one direction only: from the link to the bearer. This commit pre-empts introduction of problem c) as described above. 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>
* | tipc: redefine 'started' flag in struct link to bitmapYing Xue2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the 'started' field in struct tipc_link represents only a binary state, 'started' or 'not started'. We need it to represent more link execution states in the coming commits in this series. Hence, we rename the field to 'flags', and define the current started/non-started state to be represented by the LSB bit of that field. 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>
* | tipc: move code for deleting links from bearer.c to link.cYing Xue2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We break out the code for deleting attached links in the function bearer_disable(), and define a new function named tipc_link_delete_list() to do this job. This commit incurs no functional changes, but makes the code of function bearer_disable() cleaner. It is also a preparation for a more important change to the bearer code, in a subsequent commit in this 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>
* | tipc: move code for resetting links from bearer.c to link.cYing Xue2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We break out the code for resetting attached links in the function tipc_reset_bearer(), and define a new function named tipc_link_reset_list() to do this job. This commit incurs no functional changes, but makes the code of function tipc_reset_bearer() cleaner. It is also a preparation for a more important change to the bearer code, in a subsequent commit in this 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>
* | tipc: stricter behavior of message reassembly functionJon Paul Maloy2014-02-13
|/ | | | | | | | | | | | | | | | | | | | | | | | The function tipc_link_recv_fragment(struct sk_buff **buf) currently leaves the value of the input buffer pointer undefined when it returns, except when the return code indicates that the reassembly is complete. This despite the fact that it always consumes the input buffer. Here, we enforce a stricter behavior by this function, ensuring that the returned buffer pointer is non-NULL if and only if the reassembly is complete. This makes it possible to test for the buffer pointer as criteria for successful reassembly. We also rename the function to tipc_link_frag_rcv(), which is both shorter and more in line with common naming practice in the network subsystem. Apart from the new name, these changes have no impact on current users of the function, but makes it more practical for use in some planned future commits. 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>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2014-01-14
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| * tipc: correctly unlink packets from deferred packet queueErik Hugne2014-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we pull a received packet from a link's 'deferred packets' queue for processing, its 'next' pointer is not cleared, and still refers to the next packet in that queue, if any. This is incorrect, but caused no harm before commit 40ba3cdf542a469aaa9083fa041656e59b109b90 ("tipc: message reassembly using fragment chain") was introduced. After that commit, it may sometimes lead to the following oops: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC Modules linked in: tipc CPU: 4 PID: 0 Comm: swapper/4 Tainted: G W 3.13.0-rc2+ #6 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 task: ffff880017af4880 ti: ffff880017aee000 task.ti: ffff880017aee000 RIP: 0010:[<ffffffff81710694>] [<ffffffff81710694>] skb_try_coalesce+0x44/0x3d0 RSP: 0018:ffff880016603a78 EFLAGS: 00010212 RAX: 6b6b6b6bd6d6d6d6 RBX: ffff880013106ac0 RCX: ffff880016603ad0 RDX: ffff880016603ad7 RSI: ffff88001223ed00 RDI: ffff880013106ac0 RBP: ffff880016603ab8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88001223ed00 R13: ffff880016603ad0 R14: 000000000000058c R15: ffff880012297650 FS: 0000000000000000(0000) GS:ffff880016600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 000000000805b000 CR3: 0000000011f5d000 CR4: 00000000000006e0 Stack: ffff880016603a88 ffffffff810a38ed ffff880016603aa8 ffff88001223ed00 0000000000000001 ffff880012297648 ffff880016603b68 ffff880012297650 ffff880016603b08 ffffffffa0006c51 ffff880016603b08 00ffffffa00005fc Call Trace: <IRQ> [<ffffffff810a38ed>] ? trace_hardirqs_on+0xd/0x10 [<ffffffffa0006c51>] tipc_link_recv_fragment+0xd1/0x1b0 [tipc] [<ffffffffa0007214>] tipc_recv_msg+0x4e4/0x920 [tipc] [<ffffffffa00016f0>] ? tipc_l2_rcv_msg+0x40/0x250 [tipc] [<ffffffffa000177c>] tipc_l2_rcv_msg+0xcc/0x250 [tipc] [<ffffffffa00016f0>] ? tipc_l2_rcv_msg+0x40/0x250 [tipc] [<ffffffff8171e65b>] __netif_receive_skb_core+0x80b/0xd00 [<ffffffff8171df94>] ? __netif_receive_skb_core+0x144/0xd00 [<ffffffff8171eb76>] __netif_receive_skb+0x26/0x70 [<ffffffff8171ed6d>] netif_receive_skb+0x2d/0x200 [<ffffffff8171fe70>] napi_gro_receive+0xb0/0x130 [<ffffffff815647c2>] e1000_clean_rx_irq+0x2c2/0x530 [<ffffffff81565986>] e1000_clean+0x266/0x9c0 [<ffffffff81985f7b>] ? notifier_call_chain+0x2b/0x160 [<ffffffff8171f971>] net_rx_action+0x141/0x310 [<ffffffff81051c1b>] __do_softirq+0xeb/0x480 [<ffffffff819817bb>] ? _raw_spin_unlock+0x2b/0x40 [<ffffffff810b8c42>] ? handle_fasteoi_irq+0x72/0x100 [<ffffffff81052346>] irq_exit+0x96/0xc0 [<ffffffff8198cbc3>] do_IRQ+0x63/0xe0 [<ffffffff81981def>] common_interrupt+0x6f/0x6f <EOI> This happens when the last fragment of a message has passed through the the receiving link's 'deferred packets' queue, and at least one other packet was added to that queue while it was there. After the fragment chain with the complete message has been successfully delivered to the receiving socket, it is released. Since 'next' pointer of the last fragment in the released chain now is non-NULL, we get the crash shown above. We fix this by clearing the 'next' pointer of all received packets, including those being pulled from the 'deferred' queue, before they undergo any further processing. Fixes: 40ba3cdf542a4 ("tipc: message reassembly using fragment chain") Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reported-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>
* | tipc: make link start event synchronousJon Paul Maloy2014-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a link is created we delay the start event by launching it to be executed later in a tasklet. As we hold all the necessary locks at the moment of creation, and there is no risk of deadlock or contention, this delay serves no purpose in the current code. We remove this obsolete indirection step, and the associated function link_start(). At the same time, we rename the function tipc_link_stop() to the more appropriate tipc_link_purge_queues(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: remove 'has_redundant_link' flag from STATE link protocol messagesJon Paul Maloy2014-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The flag 'has_redundant_link' is defined only in RESET and ACTIVATE protocol messages. Due to an ambiguity in the protocol specification it is currently also transferred in STATE messages. Its value is used to initialize a link state variable, 'permit_changeover', which is used to inhibit futile link failover attempts when it is known that the peer node has no working links at the moment, although the local node may still think it has one. The fact that 'has_redundant_link' incorrectly is read from STATE messages has the effect that 'permit_changeover' sometimes gets a wrong value, and permanently blocks any links from being re-established. Such failures can only occur in in dual-link systems, and are extremely rare. This bug seems to have always been present in the code. Furthermore, since commit b4b5610223f17790419b03eaa962b0e3ecf930d7 ("tipc: Ensure both nodes recognize loss of contact between them"), the 'permit_changeover' field serves no purpose any more. The task of enforcing 'lost contact' cycles at both peer endpoints is now taken by a new mechanism, using the flags WAIT_NODE_DOWN and WAIT_PEER_DOWN in struct tipc_node to abort unnecessary failover attempts. We therefore remove the 'has_redundant_link' flag from STATE messages, as well as the now redundant 'permit_changeover' variable. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: rename functions related to link failover and improve commentsJon Paul Maloy2014-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The functionality related to link addition and failover is unnecessarily hard to understand and maintain. We try to improve this by renaming some of the functions, at the same time adding or improving the explanatory comments around them. Names such as "tipc_rcv()" etc. also align better with what is used in other networking components. The changes in this commit are purely cosmetic, no functional changes are made. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: make local function staticstephen hemminger2014-01-04
| | | | | | | | | | Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tipc: remove unused 'blocked' flag from tipc_link structYing Xue2013-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In early versions of TIPC it was possible to administratively block individual links through the use of the member flag 'blocked'. This functionality was deemed redundant, and since commit 7368dd ("tipc: clean out all instances of #if 0'd unused code"), this flag has been unused. In the current code, a link only needs to be blocked for sending and reception if it is subject to an ongoing link failover. In that case, it is sufficient to check if the number of expected failover packets is non-zero, something which is done via the funtion 'link_blocked()'. This commit finally removes the redundant 'blocked' flag completely. 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>
* | tipc: eliminate redundant code with kfree_skb_list routineYing Xue2013-12-11
| | | | | | | | | | | | | | | | | | | | | | | | sk_buff lists are currently relased by looping over the list and explicitly releasing each buffer. We replace all occurrences of this loop with a call to kfree_skb_list(). 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>
* | tipc: remove interface state mirroring in bearerErik Hugne2013-12-09
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* tipc: fix dereference before check warningErik Hugne2013-11-15
| | | | | | | | | | | | This fixes the following Smatch warning: net/tipc/link.c:2364 tipc_link_recv_fragment() warn: variable dereferenced before check '*head' (see line 2361) A null pointer might be passed to skb_try_coalesce if a malicious sender injects orphan fragments on a link. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: reassembly failures should cause link resetErik Hugne2013-11-07
| | | | | | | | | | | | | | | | | | | | If appending a received fragment to the pending fragment chain in a unicast link fails, the current code tries to force a retransmission of the fragment by decrementing the 'next received sequence number' field in the link. This is done under the assumption that the failure is caused by an out-of-memory situation, an assumption that does not hold true after the previous patch in this series. A failure to append a fragment can now only be caused by a protocol violation by the sending peer, and it must hence be assumed that it is either malicious or buggy. Either way, the correct behavior is now to reset the link instead of trying to revert its sequence number. So, this is what we do in this commit. Signed-off-by: Erik Hugne <erik.hugne@ericsson.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>
* tipc: message reassembly using fragment chainErik Hugne2013-11-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the first fragment of a long data data message is received on a link, a reassembly buffer large enough to hold the data from this and all subsequent fragments of the message is allocated. The payload of each new fragment is copied into this buffer upon arrival. When the last fragment is received, the reassembled message is delivered upwards to the port/socket layer. Not only is this an inefficient approach, but it may also cause bursts of reassembly failures in low memory situations. since we may fail to allocate the necessary large buffer in the first place. Furthermore, after 100 subsequent such failures the link will be reset, something that in reality aggravates the situation. To remedy this problem, this patch introduces a different approach. Instead of allocating a big reassembly buffer, we now append the arriving fragments to a reassembly chain on the link, and deliver the whole chain up to the socket layer once the last fragment has been received. This is safe because the retransmission layer of a TIPC link always delivers packets in strict uninterrupted order, to the reassembly layer as to all other upper layers. Hence there can never be more than one fragment chain pending reassembly at any given time in a link, and we can trust (but still verify) that the fragments will be chained up in the correct order. Signed-off-by: Erik Hugne <erik.hugne@ericsson.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>
* tipc: don't reroute message fragmentsErik Hugne2013-11-07
| | | | | | | | | | | | | | | | | | | | When a message fragment is received in a broadcast or unicast link, the reception code will append the fragment payload to a big reassembly buffer through a call to the function tipc_recv_fragm(). However, after the return of that call, the logics goes on and passes the fragment buffer to the function tipc_net_route_msg(), which will simply drop it. This behavior is a remnant from the now obsolete multi-cluster functionality, and has no relevance in the current code base. Although currently harmless, this unnecessary call would be fatal after applying the next patch in this series, which introduces a completely new reassembly algorithm. So we change the code to eliminate the redundant call. Signed-off-by: Erik Hugne <erik.hugne@ericsson.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>
* tipc: remove two indentation levels in tipc_recv_msg routineYing Xue2013-10-30
| | | | | | | | | | | | | | | | | | The message dispatching part of tipc_recv_msg() is wrapped layers of while/if/if/switch, causing out-of-control indentation and does not look very good. We reduce two indentation levels by separating the message dispatching from the blocks that checks link state and sequence numbers, allowing longer function and arg names to be consistently indented without wrapping. Additionally we also rename "cont" label to "discard" and add one new label called "unlock_discard" to make code clearer. In all, these are cosmetic changes that do not alter the operation of TIPC in any way. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Cc: David Laight <david.laight@aculab.com> Cc: Andreas Bofjäll <andreas.bofjall@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: simplify the link lookup routineErik Hugne2013-10-18
| | | | | | | | | | | | | | | When checking statistics or changing parameters on a link, the link_find_link function is used to locate the link with a given name. The complex method of deconstructing the name into local and remote address/interface is error prone and may fail if the interface names contains special characters. We change the lookup method to iterate over the list of nodes and compare the link names. Signed-off-by: Erik Hugne <erik.hugne@ericsson.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>
* tipc: correct return value of link_cmd_set_value routineYing Xue2013-10-18
| | | | | | | | | | | | | | | | | | link_cmd_set_value() takes commands for link, bearer and media related configuration. Genereally the function returns 0 when a command is recognized, and -EINVAL when it is not. However, in the switch for link related commands it returns 0 even when the command is unrecognized. This will sometimes make it look as if a failed configuration command has been successful, but has otherwise no negative effects. We remove this anomaly by returning -EINVAL even for link commands. We also rework all three switches to make them conforming to common kernel coding style. 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>
* tipc: silence sparse warningsYing Xue2013-10-18
| | | | | | | | | | | | | | | | | | Eliminate below sparse warnings: net/tipc/link.c:1210:37: warning: cast removes address space of expression net/tipc/link.c:1218:59: warning: incorrect type in argument 2 (different address spaces) net/tipc/link.c:1218:59: expected void const [noderef] <asn:1>*from net/tipc/link.c:1218:59: got unsigned char const [usertype] *[assigned] sect_crs net/tipc/socket.c:341:49: warning: Using plain integer as NULL pointer net/tipc/socket.c:1371:36: warning: Using plain integer as NULL pointer net/tipc/socket.c:1694:57: warning: Using plain integer as NULL pointer Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Andreas Bofjäll <andreas.bofjall@ericsson.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>
* tipc: remove iovec length parameter from all sending functionsYing Xue2013-10-18
| | | | | | | | | | | | | | tipc_msg_build() now copies message data from iovec to skb_buff using memcpy_fromiovecend(), which doesn't need to be passed the iovec length to perform the copying. So we remove the parameter indicating iovec length in all functions where TIPC messages are built and sent. 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>
* tipc: fix wrong return value for link_send_sections_long routineYing Xue2013-06-17
| | | | | | | | | | When skb buffer cannot be allocated in link_send_sections_long(), -ENOMEM error code instead of -EFAULT should be returned to its caller. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: make tipc_link_send_sections_fast exit earlierYing Xue2013-06-17
| | | | | | | | | | | Once message build request function returns invalid code, the process of sending message cannot continue. So in case of message build failure, tipc_link_send_sections_fast() should return immediately. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: enhance priority of link protocol packetYing Xue2013-06-17
| | | | | | | | | | | | | | | | | | | | | pfifo_fast is set as default traffic class queueing discipline. This queue has three so called "bands". Within each band, FIFO rules apply. However, as long as there are packets waiting in band 0, band 1 won't be processed. Now all kind of TIPC type packet priorities are never set, that is, their priorities are 0, so they are mapped to band 1 of pfifo_fast qdisc. But, especially during link congestion, if link protocol packet can be sent out as earlier as possible than other type of packets so that protocol packet can arrive at peer endpoint in time, the peer will timely reset its link timeout timer to keep the link alive. So enhancing the priority of link protocol packets can meet the specific demand to avoid unnecessary link reset due to a transient link congestion. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: cosmetic realignment of function argumentsPaul Gortmaker2013-06-17
| | | | | | | | | 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>
* tipc: remove user_port instance from tipc_port structureYing Xue2013-06-17
| | | | | | | | | | | | After the native API has been completely removed, the 'user_port' field in struct tipc_port becomes unused, and can be removed. As a consequence, the "usrmem" argument in tipc_msg_build() is no longer needed, and so we remove that one too. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: delete code orphaned by new server infrastructureYing Xue2013-06-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having completed the conversion of the topology server and configuration server to use the new server infrastructure, the following functions become unused, and can be deleted: - tipc_createport() - port_wakeup_sh() - port_dispatcher() - port_dispatcher_sigh() - tipc_send_buf_fast() - tipc_send_buf2port Additionally, the following variables become orphaned, and can be deleted: - tipc_msg_err_event - tipc_named_msg_err_event - tipc_conn_shutdown_event - tipc_msg_event - tipc_named_msg_event - tipc_conn_msg_event - tipc_continue_event - msg_queue_head - msg_queue_tail - queue_lock Deletion is done here in a separate commit in order to allow the actual conversion changes to be more easily viewed. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: potential divide by zero in tipc_link_recv_fragment()Dan Carpenter2013-05-06
| | | | | | | | The worry here is that fragm_sz could be zero since it comes from skb->data. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: add a bounds check in link_recv_changeover_msg()Dan Carpenter2013-05-06
| | | | | | | | | The bearer_id here comes from skb->data and it can be a number from 0 to 7. The problem is that the ->links[] array has only 2 elements so I have added a range check. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tipc: remove obsolete flush of stale reassembly bufferErik Hugne2012-12-06
| | | | | | | | | | | | | | | | | | | | | | | | Each link instance has a periodic job checking if there is a stale ongoing message reassembly associated to the link. If no new fragment has been received during the last 4*[link_tolerance] period, it is assumed the missing fragment will never arrive. As a consequence, the reassembly buffer is discarded, and a gap in the message sequence occurs. This assumption is wrong. After we abandoned our ambition to develop packet routing for multi-cluster networks, only single-hop packet transfer remains as an option. For those, all packets are guaranteed to be delivered in sequence to the defragmentation layer. Any failure to achieve sequenced delivery will eventually lead to link reset, and the reassembly buffer will be flushed anyway. So we just remove this periodic check, which is now obsolete. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> [PG: also delete get/inc_timer count, since they are now unused] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* tipc: introduce message to synchronize broadcast linkJon Maloy2012-11-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Upon establishing a first link between two nodes, there is currently a risk that the two endpoints will disagree on exactly which sequence number reception and acknowleding of broadcast packets should start. The following scenarios may happen: 1: Node A sends an ACTIVATE message to B, telling it to start acking packets from sequence number N. 2: Node A sends out broadcast N, but does not expect an acknowledge from B, since B is not yet in its broadcast receiver's list. 3: Node A receives ACK for N from all nodes except B, and releases packet N. 4: Node B receives the ACTIVATE, activates its link endpoint, and stores the value N as sequence number of first expected packet. 5: Node B sends a NAME_DISTR message to A. 6: Node A receives the NAME_DISTR message, and activates its endpoint. At this moment B is added to A's broadcast receiver's set. Node A also sets sequence number 0 as the first broadcast packet to be received from B. 7: Node A sends broadcast N+1. 8: B receives N+1, determines there is a gap in the sequence, since it is expecting N, and sends a NACK for N back to A. 9: Node A has already released N, so no retransmission is possible. The broadcast link in direction A->B is stale. In addition to, or instead of, 7-9 above, the following may happen: 10: Node B sends broadcast M > 0 to A. 11: Node A receives M, falsely decides there must be a gap, since it is expecting packet 0, and asks for retransmission of packets [0,M-1]. 12: Node B has already released these packets, so the broadcast link is stale in direction B->A. We solve this problem by introducing a new unicast message type, BCAST_PROTOCOL/STATE, to convey the sequence number of the next sent broadcast packet to the other endpoint, at exactly the moment that endpoint is added to the own node's broadcast receivers list, and before any other unicast messages are permitted to be sent. Furthermore, we don't allow any node to start receiving and processing broadcast packets until this new synchronization message has been received. To maintain backwards compatibility, we still open up for broadcast reception if we receive a NAME_DISTR message without any preceding broadcast sync message. In this case, we must assume that the other end has an older code version, and will never send out the new synchronization message. Hence, for mixed old and new nodes, the issue arising in 7-12 of the above may happen with the same probability as before. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* tipc: rename supported flag to recv_permittedYing Xue2012-11-22
| | | | | | | | | | | | Rename the "supported" flag in bclink structure to "recv_permitted" to better reflect what it is used for. When this flag is set for a given node, we are permitted to receive and acknowledge broadcast messages from that node. Convert it to a bool at the same time, since it is not used to store any numerical values. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>