linux-toradex.git/net/bridge/br_sysfs_if.c, branch v5.12-rc8

net: bridge: don't print in br_switchdev_set_port_flag

2021-02-13T01:08:04+00:00

For the netlink interface, propagate errors through extack rather than
simply printing them to the console. For the sysfs interface, we still
print to the console, but at least that's one layer higher than in
switchdev, which also allows us to silently ignore the offloading of
flags if that is ever needed in the future.

Signed-off-by: Vladimir Oltean 
Acked-by: Nikolay Aleksandrov 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller

net: bridge: use switchdev for port flags set through sysfs too

2021-02-08T23:43:19+00:00

Looking through patchwork I don't see that there was any consensus to
use switchdev notifiers only in case of netlink provided port flags but
not sysfs (as a sort of deprecation, punishment or anything like that),
so we should probably keep the user interface consistent in terms of
functionality.

http://patchwork.ozlabs.org/project/netdev/patch/20170605092043.3523-3-jiri@resnulli.us/
http://patchwork.ozlabs.org/project/netdev/patch/20170608064428.4785-3-jiri@resnulli.us/

Fixes: 3922285d96e7 ("net: bridge: Add support for offloading port attributes")
Signed-off-by: Vladimir Oltean 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

net: bridge: add warning comments to avoid extending sysfs

2021-01-30T05:33:02+00:00

We're moving to netlink-only options, so add comments in the bridge's
sysfs files to warn against adding any new sysfs entries.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: Jakub Kicinski

net: bridge: mcast: drop hosts limit sysfs support

2021-01-30T05:33:02+00:00

We decided to stop adding new sysfs bridge options and continue with
netlink only, so remove hosts limit sysfs support.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: Jakub Kicinski

net: bridge: multicast: make tracked EHT hosts limit configurable

2021-01-28T01:40:35+00:00

Add two new port attributes which make EHT hosts limit configurable and
export the current number of tracked EHT hosts:
 - IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT: configure/retrieve current limit
 - IFLA_BRPORT_MCAST_EHT_HOSTS_CNT: current number of tracked hosts
Setting IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT to 0 is currently not allowed.

Note that we have to increase RTNL_SLAVE_MAX_TYPE to 38 minimum, I've
increased it to 40 to have space for two more future entries.

v2: move br_multicast_eht_set_hosts_limit() to br_multicast_eht.c,
    no functional change

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: Jakub Kicinski

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

net: bridge: remove redundant checks for null p->dev and p->br

2018-11-25T18:25:43+00:00

A recent change added a null check on p->dev after p->dev was being
dereferenced by the ns_capable check on p->dev. It turns out that
neither the p->dev and p->br null checks are necessary, and can be
removed, which cleans up a static analyis warning.

As Nikolay Aleksandrov noted, these checks can be removed because:

"My reasoning of why it shouldn't be possible:
- On port add new_nbp() sets both p->dev and p->br before creating
  kobj/sysfs

- On port del (trickier) del_nbp() calls kobject_del() before call_rcu()
  to destroy the port which in turn calls sysfs_remove_dir() which uses
  kernfs_remove() which deactivates (shouldn't be able to open new
  files) and calls kernfs_drain() to drain current open/mmaped files in
  the respective dir before continuing, thus making it impossible to
  open a bridge port sysfs file with p->dev and p->br equal to NULL.

So I think it's safe to remove those checks altogether. It'd be nice to
get a second look over my reasoning as I might be missing something in
sysfs/kernfs call path."

Thanks to Nikolay Aleksandrov's suggestion to remove the check and
David Miller for sanity checking this.

Detected by CoverityScan, CID#751490 ("Dereference before null check")

Fixes: a5f3ea54f3cc ("net: bridge: add support for raw sysfs port options")
Signed-off-by: Colin Ian King 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

net: bridge: add support for backup port

2018-07-23T16:32:15+00:00

This patch adds a new port attribute - IFLA_BRPORT_BACKUP_PORT, which
allows to set a backup port to be used for known unicast traffic if the
port has gone carrier down. The backup pointer is rcu protected and set
only under RTNL, a counter is maintained so when deleting a port we know
how many other ports reference it as a backup and we remove it from all.
Also the pointer is in the first cache line which is hot at the time of
the check and thus in the common case we only add one more test.
The backup port will be used only for the non-flooding case since
it's a part of the bridge and the flooded packets will be forwarded to it
anyway. To remove the forwarding just send a 0/non-existing backup port.
This is used to avoid numerous scalability problems when using MLAG most
notably if we have thousands of fdbs one would need to change all of them
on port carrier going down which takes too long and causes a storm of fdb
notifications (and again when the port comes back up). In a Multi-chassis
Link Aggregation setup usually hosts are connected to two different
switches which act as a single logical switch. Those switches usually have
a control and backup link between them called peerlink which might be used
for communication in case a host loses connectivity to one of them.
We need a fast way to failover in case a host port goes down and currently
none of the solutions (like bond) cannot fulfill the requirements because
the participating ports are actually the "master" devices and must have the
same peerlink as their backup interface and at the same time all of them
must participate in the bridge device. As Roopa noted it's normal practice
in routing called fast re-route where a precalculated backup path is used
when the main one is down.
Another use case of this is with EVPN, having a single vxlan device which
is backup of every port. Due to the nature of master devices it's not
currently possible to use one device as a backup for many and still have
all of them participate in the bridge (which is master itself).
More detailed information about MLAG is available at the link below.
https://docs.cumulusnetworks.com/display/DOCS/Multi-Chassis+Link+Aggregation+-+MLAG

Further explanation and a diagram by Roopa:
Two switches acting in a MLAG pair are connected by the peerlink
interface which is a bridge port.

the config on one of the switches looks like the below. The other
switch also has a similar config.
eth0 is connected to one port on the server. And the server is
connected to both switches.

br0 -- team0---eth0
      |
      -- switch-peerlink

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

net: bridge: add support for raw sysfs port options

2018-07-23T16:32:15+00:00

This patch adds a new alternative store callback for port sysfs options
which takes a raw value (buf) and can use it directly. It is needed for the
backup port sysfs support since we have to pass the device by its name.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: make sure objects belong to container's owner

2018-07-21T06:44:36+00:00

When creating various bridge objects in /sys/class/net/... make sure
that they belong to the container's owner instead of global root (if
they belong to a container/namespace).

Signed-off-by: Tyler Hicks 
Signed-off-by: David S. Miller