linux.git/net/dsa/slave.c, branch v5.16

net: dsa: populate supported_interfaces member

2021-11-01T13:06:32+00:00

Add a new DSA switch operation, phylink_get_interfaces, which should
fill in which PHY_INTERFACE_MODE_* are supported by given port.

Use this before phylink_create() to fill phylinks supported_interfaces
member, allowing phylink to determine which PHY_INTERFACE_MODEs are
supported.

Signed-off-by: Marek Behún 
[tweaked patch and description to add more complete support -- rmk]
Signed-off-by: Russell King 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: David S. Miller

net: switchdev: merge switchdev_handle_fdb_{add,del}_to_device

2021-10-27T13:54:02+00:00

To reduce code churn, the same patch makes multiple changes, since they
all touch the same lines:

1. The implementations for these two are identical, just with different
   function pointers. Reduce duplications and name the function pointers
   "mod_cb" instead of "add_cb" and "del_cb". Pass the event as argument.

2. Drop the "const" attribute from "orig_dev". If the driver needs to
   check whether orig_dev belongs to itself and then
   call_switchdev_notifiers(orig_dev, SWITCHDEV_FDB_OFFLOADED), it
   can't, because call_switchdev_notifiers takes a non-const struct
   net_device *.

Signed-off-by: Vladimir Oltean 
Reviewed-by: Ido Schimmel 
Signed-off-by: David S. Miller

net: dsa: stop calling dev_hold in dsa_slave_fdb_event

2021-10-26T14:07:35+00:00

Now that we guarantee that SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE events have
finished executing by the time we leave our bridge upper interface,
we've established a stronger boundary condition for how long the
dsa_slave_switchdev_event_work() might run.

As such, it is no longer possible for DSA slave interfaces to become
unregistered, since they are still bridge ports.

So delete the unnecessary dev_hold() and dev_put().

Signed-off-by: Vladimir Oltean 
Signed-off-by: David S. Miller

net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work

2021-10-25T11:59:42+00:00

After talking with Ido Schimmel, it became clear that rtnl_lock is not
actually required for anything that is done inside the
SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE deferred work handlers.

The reason why it was probably added by Arkadi Sharshevsky in commit
c9eb3e0f8701 ("net: dsa: Add support for learning FDB through
notification") was to offer the same locking/serialization guarantees as
.ndo_fdb_{add,del} and avoid reworking any drivers.

DSA has implemented .ndo_fdb_add and .ndo_fdb_del until commit
b117e1e8a86d ("net: dsa: delete dsa_legacy_fdb_add and
dsa_legacy_fdb_del") - that is to say, until fairly recently.

But those methods have been deleted, so now we are free to drop the
rtnl_lock as well.

Note that exposing DSA switch drivers to an unlocked method which was
previously serialized by the rtnl_mutex is a potentially dangerous
affair. Driver writers couldn't ensure that their internal locking
scheme does the right thing even if they wanted.

We could err on the side of paranoia and introduce a switch-wide lock
inside the DSA framework, but that seems way overreaching. Instead, we
could check as many drivers for regressions as we can, fix those first,
then let this change go in once it is assumed to be fairly safe.

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

Revert "Merge branch 'dsa-rtnl'"

2021-10-25T11:59:25+00:00

This reverts commit 965e6b262f48257dbdb51b565ecfd84877a0ab5f, reversing
changes made to 4d98bb0d7ec2d0b417df6207b0bafe1868bad9f8.

net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work

2021-10-24T12:47:44+00:00

After talking with Ido Schimmel, it became clear that rtnl_lock is not
actually required for anything that is done inside the
SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE deferred work handlers.

The reason why it was probably added by Arkadi Sharshevsky in commit
c9eb3e0f8701 ("net: dsa: Add support for learning FDB through
notification") was to offer the same locking/serialization guarantees as
.ndo_fdb_{add,del} and avoid reworking any drivers.

DSA has implemented .ndo_fdb_add and .ndo_fdb_del until commit
b117e1e8a86d ("net: dsa: delete dsa_legacy_fdb_add and
dsa_legacy_fdb_del") - that is to say, until fairly recently.

But those methods have been deleted, so now we are free to drop the
rtnl_lock as well.

Note that exposing DSA switch drivers to an unlocked method which was
previously serialized by the rtnl_mutex is a potentially dangerous
affair. Driver writers couldn't ensure that their internal locking
scheme does the right thing even if they wanted.

We could err on the side of paranoia and introduce a switch-wide lock
inside the DSA framework, but that seems way overreaching. Instead, we
could check as many drivers for regressions as we can, fix those first,
then let this change go in once it is assumed to be fairly safe.

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

net: dsa: remove the "dsa_to_port in a loop" antipattern from the core

2021-10-21T11:44:06+00:00

Ever since Vivien's conversion of the ds->ports array into a dst->ports
list, and the introduction of dsa_to_port, iterations through the ports
of a switch became quadratic whenever dsa_to_port was needed.

dsa_to_port can either be called directly, or indirectly through the
dsa_is_{user,cpu,dsa,unused}_port helpers.

Use the newly introduced dsa_switch_for_each_port() iteration macro
that works with the iterator variable being a struct dsa_port *dp
directly, and not an int i. It is an expensive variable to go from i to
dp, but cheap to go from dp to i.

This macro iterates through the entire ds->dst->ports list and filters
by the ports belonging just to the switch provided as argument.

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

net: dsa: allow reporting of standard ethtool stats for slave devices

2021-10-18T13:02:55+00:00

Jakub pointed out that we have a new ethtool API for reporting device
statistics in a standardized way, via .get_eth_{phy,mac,ctrl}_stats.
Add a small amount of plumbing to allow DSA drivers to take advantage of
this when exposing statistics.

Suggested-by: Jakub Kicinski 
Signed-off-by: Alvin Šipraga 
Signed-off-by: David S. Miller

net: use eth_hw_addr_set() instead of ether_addr_copy()

2021-10-02T13:18:25+00:00

Convert from ether_addr_copy() to eth_hw_addr_set():

  @@
  expression dev, np;
  @@
  - ether_addr_copy(dev->dev_addr, np)
  + eth_hw_addr_set(dev, np)

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

net: dsa: destroy the phylink instance on any error in dsa_slave_phy_setup

2021-09-15T22:03:36+00:00

DSA supports connecting to a phy-handle, and has a fallback to a non-OF
based method of connecting to an internal PHY on the switch's own MDIO
bus, if no phy-handle and no fixed-link nodes were present.

The -ENODEV error code from the first attempt (phylink_of_phy_connect)
is what triggers the second attempt (phylink_connect_phy).

However, when the first attempt returns a different error code than
-ENODEV, this results in an unbalance of calls to phylink_create and
phylink_destroy by the time we exit the function. The phylink instance
has leaked.

There are many other error codes that can be returned by
phylink_of_phy_connect. For example, phylink_validate returns -EINVAL.
So this is a practical issue too.

Fixes: aab9c4067d23 ("net: dsa: Plug in PHYLINK support")
Signed-off-by: Vladimir Oltean 
Reviewed-by: Florian Fainelli 
Reviewed-by: Russell King (Oracle) 
Link: https://lore.kernel.org/r/20210914134331.2303380-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski