linux-toradex.git/net/tipc/link.c, branch v4.4.89

tipc: move linearization of buffers to generic code

2016-09-24T08:07:35+00:00

commit c7cad0d6f70cd4ce8644ffe528a4df1cdc2e77f5 upstream.

In commit 5cbb28a4bf65c7e4 ("tipc: linearize arriving NAME_DISTR
and LINK_PROTO buffers") we added linearization of NAME_DISTRIBUTOR,
LINK_PROTOCOL/RESET and LINK_PROTOCOL/ACTIVATE to the function
tipc_udp_recv(). The location of the change was selected in order
to make the commit easily appliable to 'net' and 'stable'.

We now move this linearization to where it should be done, in the
functions tipc_named_rcv() and tipc_link_proto_rcv() respectively.

Reviewed-by: Ying Xue 
Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller 
Signed-off-by: Juerg Haefliger 
Signed-off-by: Greg Kroah-Hartman

tipc: correct settings of broadcast link state

2015-11-20T19:08:51+00:00

Since commit 5266698661401afc5e ("tipc: let broadcast packet
reception use new link receive function") the broadcast send
link state was meant to always be set to LINK_ESTABLISHED, since
we don't need this link to follow the regular link FSM rules. It
was also the intention that this state anyway shouldn't impact
the run-time working state of the link, since the latter in
reality is controlled by the number of registered peers.

We have now discovered that this assumption is not quite correct.
If the broadcast link is reset because of too many retransmissions,
its state will inadvertently go to LINK_RESETTING, and never go
back to LINK_ESTABLISHED, because the LINK_FAILURE event was not
anticipated. This will work well once, but if it happens a second
time, the reset on a link in LINK_RESETTING has has no effect, and
neither the broadcast link nor the unicast links will go down as
they should.

Furthermore, it is confusing that the management tool shows that
this link is in UP state when that obviously isn't the case.

We now ensure that this state strictly follows the true working
state of the link. The state is set to LINK_ESTABLISHED when
the number of peers is non-zero, and to LINK_RESET otherwise.

Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: link_is_bc_sndlink() can be static

2015-10-25T13:31:52+00:00

TO: "David S. Miller" 
CC: netdev@vger.kernel.org
CC: Jon Maloy 
CC: Ying Xue 
CC: tipc-discussion@lists.sourceforge.net
CC: linux-kernel@vger.kernel.org

Signed-off-by: Fengguang Wu 
Acked-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: clean up unused code and structures

2015-10-24T13:56:47+00:00

After the previous changes in this series, we can now remove some
unused code and structures, both in the broadcast, link aggregation
and link code.

There are no functional changes in this commit.

Signed-off-by: Jon Maloy 
Reviewed-by: Ying Xue 
Signed-off-by: David S. Miller

tipc: eliminate link's reference to owner node

2015-10-24T13:56:45+00:00

With the recent commit series, we have established a one-way dependency
between the link aggregation (struct tipc_node) instances and their
pertaining tipc_link instances. This has enabled quite significant code
and structure simplifications.

In this commit, we eliminate the field 'owner', which points to an
instance of struct tipc_node, from struct tipc_link, and replace it with
a pointer to struct net, which is the only external reference now needed
by a link instance.

Signed-off-by: Jon Maloy 
Reviewed-by: Ying Xue 
Signed-off-by: David S. Miller

tipc: let neighbor discoverer tranmsit consumable buffers

2015-10-24T13:56:44+00:00

The neighbor discovery function currently uses the function
tipc_bearer_send() for transmitting packets, assuming that the
sent buffers are not consumed by the called function.

We want to change this, in order to avoid unnecessary buffer cloning
elswhere in the code.

This commit introduces a new function tipc_bearer_skb() which consumes
the sent buffers, and let the discoverer functions use this new call
instead. The discoverer does now itself perform the cloning when
that is necessary.

Signed-off-by: Jon Maloy 
Reviewed-by: Ying Xue 
Signed-off-by: David S. Miller

tipc: introduce jumbo frame support for broadcast

2015-10-24T13:56:40+00:00

Until now, we have only been supporting a fix MTU size of 1500 bytes
for all broadcast media, irrespective of their actual capability.

We now make the broadcast MTU adaptable to the carrying media, i.e.,
we use the smallest MTU supported by any of the interfaces attached
to TIPC.

Signed-off-by: Jon Maloy 
Reviewed-by: Ying Xue 
Signed-off-by: David S. Miller

tipc: let broadcast packet reception use new link receive function

2015-10-24T13:56:37+00:00

The code path for receiving broadcast packets is currently distinct
from the unicast path. This leads to unnecessary code and data
duplication, something that can be avoided with some effort.

We now introduce separate per-peer tipc_link instances for handling
broadcast packet reception. Each receive link keeps a pointer to the
common, single, broadcast link instance, and can hence handle release
and retransmission of send buffers as if they belonged to the own
instance.

Furthermore, we let each unicast link instance keep a reference to both
the pertaining broadcast receive link, and to the common send link.
This makes it possible for the unicast links to easily access data for
broadcast link synchronization, as well as for carrying acknowledges for
received broadcast packets.

Signed-off-by: Jon Maloy 
Reviewed-by: Ying Xue 
Signed-off-by: David S. Miller

tipc: introduce capability bit for broadcast synchronization

2015-10-24T13:56:35+00:00

Until now, we have tried to support both the newer, dedicated broadcast
synchronization mechanism along with the older, less safe, RESET_MSG/
ACTIVATE_MSG based one. The latter method has turned out to be a hazard
in a highly dynamic cluster, so we find it safer to disable it completely
when we find that the former mechanism is supported by the peer node.

For this purpose, we now introduce a new capabability bit,
TIPC_BCAST_SYNCH, to inform any peer nodes that dedicated broadcast
syncronization is supported by the present node. The new bit is conveyed
between peers in the 'capabilities' field of neighbor discovery messages.

Signed-off-by: Jon Maloy 
Reviewed-by: Ying Xue 
Signed-off-by: David S. Miller

tipc: let broadcast transmission use new link transmit function

2015-10-24T13:56:32+00:00

This commit simplifies the broadcast link transmission function, by
leveraging previous changes to the link transmission function and the
broadcast transmission link life cycle.

Signed-off-by: Jon Maloy 
Reviewed-by: Ying Xue 
Signed-off-by: David S. Miller