kernel/linux.git/net/tipc/link.c, branch linux-5.9.y

net: tipc: kerneldoc fixes

2020-09-15T20:33:04+00:00

Fix parameter description of tipc_link_bc_create() Reported-by: Hulk Robot Fixes: 16ad3f4022bb ("tipc: introduce variable window congestion control") Signed-off-by: Lu Wei Signed-off-by: David S. Miller

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-07-26T00:49:04+00:00

The UDP reuseport conflict was a little bit tricky. The net-next code, via bpf-next, extracted the reuseport handling into a helper so that the BPF sk lookup code could invoke it. At the same time, the logic for reuseport handling of unconnected sockets changed via commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace which changed the logic to carry on the reuseport result into the rest of the lookup loop if we do not return immediately. This requires moving the reuseport_has_conns() logic into the callers. While we are here, get rid of inline directives as they do not belong in foo.c files. The other changes were cases of more straightforward overlapping modifications. Signed-off-by: David S. Miller

tipc: allow to build NACK message in link timeout function

2020-07-21T03:11:22+00:00

Commit 02288248b051 ("tipc: eliminate gap indicator from ACK messages") eliminated sending of the 'gap' indicator in regular ACK messages and only allowed to build NACK message with enabled probe/probe_reply. However, necessary correction for building NACK message was missed in tipc_link_timeout() function. This leads to significant delay and link reset (due to retransmission failure) in lossy environment. This commit fixes it by setting the 'probe' flag to 'true' when the receive deferred queue is not empty. As a result, NACK message will be built to send back to another peer. Fixes: 02288248b051 ("tipc: eliminate gap indicator from ACK messages") Acked-by: Jon Maloy Signed-off-by: Tung Nguyen Signed-off-by: David S. Miller

net: tipc: kerneldoc fixes

2020-07-14T00:20:40+00:00

Simple fixes which require no deep knowledge of the code. Cc: Jon Maloy Cc: Ying Xue Signed-off-by: Andrew Lunn Acked-by: Jon Maloy Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-07-11T07:46:00+00:00

All conflicts seemed rather trivial, with some guidance from Saeed Mameed on the tc_ct.c one. Signed-off-by: David S. Miller

tipc: fix retransmission on unicast links

2020-07-08T22:39:50+00:00

A scenario has been observed where a 'bc_init' message for a link is not retransmitted if it fails to be received by the peer. This leads to the peer never establishing the link fully and it discarding all other data received on the link. In this scenario the message is lost in transit to the peer. The issue is traced to the 'nxt_retr' field of the skb not being initialised for links that aren't a bc_sndlink. This leads to the comparison in tipc_link_advance_transmq() that gates whether to attempt retransmission of a message performing in an undesirable way. Depending on the relative value of 'jiffies', this comparison: time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr) may return true or false given that 'nxt_retr' remains at the uninitialised value of 0 for non bc_sndlinks. This is most noticeable shortly after boot when jiffies is initialised to a high value (to flush out rollover bugs) and we compare a jiffies of, say, 4294940189 to zero. In that case time_before returns 'true' leading to the skb not being retransmitted. The fix is to ensure that all skbs have a valid 'nxt_retr' time set for them and this is achieved by refactoring the setting of this value into a central function. With this fix, transmission losses of 'bc_init' messages do not stall the link establishment forever because the 'bc_init' message is retransmitted and the link eventually establishes correctly. Fixes: 382f598fb66b ("tipc: reduce duplicate packets for unicast traffic") Acked-by: Jon Maloy Signed-off-by: Hamish Martin Signed-off-by: David S. Miller

tipc: Use struct_size() helper

2020-06-20T03:15:25+00:00

Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes. This code was detected with the help of Coccinelle and, audited and fixed manually. Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

tipc: update a binding service via broadcast

2020-06-17T15:53:34+00:00

Currently, updating binding table (add service binding to name table/withdraw a service binding) is being sent over replicast. However, if we are scaling up clusters to > 100 nodes/containers this method is less affection because of looping through nodes in a cluster one by one. It is worth to use broadcast to update a binding service. This way, the binding table can be updated on all peer nodes in one shot. Broadcast is used when all peer nodes, as indicated by a new capability flag TIPC_NAMED_BCAST, support reception of this message type. Four problems need to be considered when introducing this feature. 1) When establishing a link to a new peer node we still update this by a unicast 'bulk' update. This may lead to race conditions, where a later broadcast publication/withdrawal bypass the 'bulk', resulting in disordered publications, or even that a withdrawal may arrive before the corresponding publication. We solve this by adding an 'is_last_bulk' bit in the last bulk messages so that it can be distinguished from all other messages. Only when this message has arrived do we open up for reception of broadcast publications/withdrawals. 2) When a first legacy node is added to the cluster all distribution will switch over to use the legacy 'replicast' method, while the opposite happens when the last legacy node leaves the cluster. This entails another risk of message disordering that has to be handled. We solve this by adding a sequence number to the broadcast/replicast messages, so that disordering can be discovered and corrected. Note however that we don't need to consider potential message loss or duplication at this protocol level. 3) Bulk messages don't contain any sequence numbers, and will always arrive in order. Hence we must exempt those from the sequence number control and deliver them unconditionally. We solve this by adding a new 'is_bulk' bit in those messages so that they can be recognized. 4) Legacy messages, which don't contain any new bits or sequence numbers, but neither can arrive out of order, also need to be exempt from the initial synchronization and sequence number check, and delivered unconditionally. Therefore, we add another 'is_not_legacy' bit to all new messages so that those can be distinguished from legacy messages and the latter delivered directly. v1->v2: - fix warning issue reported by kbuild test robot - add santiy check to drop the publication message with a sequence number that is lower than the agreed synch point Signed-off-by: kernel test robot Signed-off-by: Hoang Huu Le Acked-by: Jon Maloy Signed-off-by: David S. Miller

tipc: add support for broadcast rcv stats dumping

2020-05-26T22:16:52+00:00

This commit enables dumping the statistics of a broadcast-receiver link like the traditional 'broadcast-link' one (which is for broadcast- sender). The link dumping can be triggered via netlink (e.g. the iproute2/tipc tool) by the link flag - 'TIPC_NLA_LINK_BROADCAST' as the indicator. The name of a broadcast-receiver link of a specific peer will be in the format: 'broadcast-link:'. For example: Link Window:50 packets RX packets:7841 fragments:2408/440 bundles:0/0 TX packets:0 fragments:0/0 bundles:0/0 RX naks:0 defs:124 dups:0 TX naks:21 acks:0 retrans:0 Congestion link:0 Send queue max:0 avg:0 In addition, the broadcast-receiver link statistics can be reset in the usual way via netlink by specifying that link name in command. Note: the 'tipc_link_name_ext()' is removed because the link name can now be retrieved simply via the 'l->name'. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller