This patch removes the separate paths for frames coming from the outside, and
frames sent from the HSR device, and instead makes all frames go through
hsr_forward_skb() in hsr_forward.c. This greatly improves code readability and
also opens up the possibility for future support of the HSR Interlink device
that is the basis for HSR RedBoxes and HSR QuadBoxes, as well as VLAN
compatibility.

Other improvements:
* A reduction in the number of times an skb is copied on machines without
  HAVE_EFFICIENT_UNALIGNED_ACCESS, which improves throughput somewhat.
* Headers are now created using the standard eth_header(), and using the
  standard hard_header_len.
* Each HSR slave now gets its own private skb, so slave-specific fields can be
  correctly set.
Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Also try to prevent some possible slave dereference race conditions. This is
finalized in the next patch, which abandons the slave array in favour of
a list_head list and list RCU.
Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Also move the frame receive handler to hsr_slave.c.
Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use del_timer_sync to ensure that the timer is stopped on all CPUs before
the driver exists.

This change was suggested by Thomas Gleixner.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
declarer name module_exit;
identifier ex;
@@

module_exit(ex);

@@
identifier r.ex;
@@

ex(...) {
  <...
- del_timer
+ del_timer_sync
    (...)
  ...>
}
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a sanity check and we never pass invalid values so this patch
doesn't change anything.  However the node->time_in[] array has
HSR_MAX_SLAVE (2) elements and not HSR_MAX_DEV (3).
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's slightly smaller/faster for some architectures.
Make sure def_multicast_addr is __aligned(2)
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The callback function of call_rcu() just calls a kfree(), so we
can use kfree_rcu() instead of call_rcu() + callback function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This implements the rtnl_link_ops fill_info routine for HSR.
Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NArvid Brodin <arvid.brodin@alten.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Register generic netlink multicast groups as an array with
the family and give them contiguous group IDs. Then instead
of passing the global group ID to the various functions that
send messages, pass the ID relative to the family - for most
families that's just 0 because the only have one group.

This avoids the list_head and ID in each group, adding a new
field for the mcast group ID offset to the family.

At the same time, this allows us to prevent abusing groups
again like the quota and dropmon code did, since we can now
check that a family only uses a group it owns.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This doesn't really change anything, but prepares for the
next patch that will change the APIs to pass the group ID
within the family, rather than the global group ID.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There's no need to unregister the multicast group if the
generic netlink family is registered immediately after.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As suggested by David Miller, make genl_register_family_with_ops()
a macro and pass only the array, evaluating ARRAY_SIZE() in the
macro, this is a little safer.

The openvswitch has some indirection, assing ops/n_ops directly in
that code. This might ultimately just assign the pointers in the
family initializations, saving the struct genl_family_and_ops and
code (once mcast groups are handled differently.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If 'hsr_get_node_data()' returns error, going directly to 'fail' label
doesn't free the memory pointed by 'skb_out'.
Signed-off-by: NGeyslan G. Bem <geyslan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that genl_ops are no longer modified in place when
registering, they can be made const. This patch was done
mostly with spatch:

@@
identifier ops;
@@
+const
 struct genl_ops ops[] = {
 ...
 };

(except the struct thing in net/openvswitch/datapath.c)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This simplifies the code since there's no longer a
need to have error handling in the registration.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

High-availability Seamless Redundancy ("HSR") provides instant failover
redundancy for Ethernet networks. It requires a special network topology where
all nodes are connected in a ring (each node having two physical network
interfaces). It is suited for applications that demand high availability and
very short reaction time.

HSR acts on the Ethernet layer, using a registered Ethernet protocol type to
send special HSR frames in both directions over the ring. The driver creates
virtual network interfaces that can be used just like any ordinary Linux
network interface, for IP/TCP/UDP traffic etc. All nodes in the network ring
must be HSR capable.

This code is a "best effort" to comply with the HSR standard as described in
IEC 62439-3:2010 (HSRv0).
Signed-off-by: NArvid Brodin <arvid.brodin@xdin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>