| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
The Linux device model permits both the ->shutdown and ->remove driver
methods to get called during a shutdown procedure. Example: a DSA switch
which sits on an SPI bus, and the SPI bus driver calls this on its
->shutdown method:
spi_unregister_controller
-> device_for_each_child(&ctlr->dev, NULL, __unregister);
-> spi_unregister_device(to_spi_device(dev));
-> device_del(&spi->dev);
So this is a simple pattern which can theoretically appear on any bus,
although the only other buses on which I've been able to find it are
I2C:
i2c_del_adapter
-> device_for_each_child(&adap->dev, NULL, __unregister_client);
-> i2c_unregister_device(client);
-> device_unregister(&client->dev);
The implication of this pattern is that devices on these buses can be
unregistered after having been shut down. The drivers for these devices
might choose to return early either from ->remove or ->shutdown if the
other callback has already run once, and they might choose that the
->shutdown method should only perform a subset of the teardown done by
->remove (to avoid unnecessary delays when rebooting).
So in other words, the device driver may choose on ->remove to not
do anything (therefore to not unregister an MDIO bus it has registered
on ->probe), because this ->remove is actually triggered by the
device_shutdown path, and its ->shutdown method has already run and done
the minimally required cleanup.
This used to be fine until the blamed commit, but now, the following
BUG_ON triggers:
void mdiobus_free(struct mii_bus *bus)
{
/* For compatibility with error handling in drivers. */
if (bus->state == MDIOBUS_ALLOCATED) {
kfree(bus);
return;
}
BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
bus->state = MDIOBUS_RELEASED;
put_device(&bus->dev);
}
In other words, there is an attempt to free an MDIO bus which was not
unregistered. The attempt to free it comes from the devres release
callbacks of the SPI device, which are executed after the device is
unregistered.
I'm not saying that the fact that MDIO buses allocated using devres
would automatically get unregistered wasn't strange. I'm just saying
that the commit didn't care about auditing existing call paths in the
kernel, and now, the following code sequences are potentially buggy:
(a) devm_mdiobus_alloc followed by plain mdiobus_register, for a device
located on a bus that unregisters its children on shutdown. After
the blamed patch, either both the alloc and the register should use
devres, or none should.
(b) devm_mdiobus_alloc followed by plain mdiobus_register, and then no
mdiobus_unregister at all in the remove path. After the blamed
patch, nobody unregisters the MDIO bus anymore, so this is even more
buggy than the previous case which needs a specific bus
configuration to be seen, this one is an unconditional bug.
In this case, DSA falls into category (a), it tries to be helpful and
registers an MDIO bus on behalf of the switch, which might be on such a
bus. I've no idea why it does it under devres.
It does this on probe:
if (!ds->slave_mii_bus && ds->ops->phy_read)
alloc and register mdio bus
and this on remove:
if (ds->slave_mii_bus && ds->ops->phy_read)
unregister mdio bus
I _could_ imagine using devres because the condition used on remove is
different than the condition used on probe. So strictly speaking, DSA
cannot determine whether the ds->slave_mii_bus it sees on remove is the
ds->slave_mii_bus that _it_ has allocated on probe. Using devres would
have solved that problem. But nonetheless, the existing code already
proceeds to unregister the MDIO bus, even though it might be
unregistering an MDIO bus it has never registered. So I can only guess
that no driver that implements ds->ops->phy_read also allocates and
registers ds->slave_mii_bus itself.
So in that case, if unregistering is fine, freeing must be fine too.
Stop using devres and free the MDIO bus manually. This will make devres
stop attempting to free a still registered MDIO bus on ->shutdown.
Fixes: ac3a68d56651 ("net: phy: don't abuse devres in devm_mdiobus_register()")
Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Since the blamed commit, dsa_tree_teardown_switches() was split into two
smaller functions, dsa_tree_teardown_switches and dsa_tree_teardown_ports.
However, the error path of dsa_tree_setup stopped calling dsa_tree_teardown_ports.
Fixes: a57d8c217aad ("net: dsa: flush switchdev workqueue before tearing down CPU/DSA ports")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
on error
Commit 86f8b1c01a0a ("net: dsa: Do not make user port errors fatal")
decided it was fine to ignore errors on certain ports that fail to
probe, and go on with the ports that do probe fine.
Commit fb6ec87f7229 ("net: dsa: Fix type was not set for devlink port")
noticed that devlink_port_type_eth_set(dlp, dp->slave); does not get
called, and devlink notices after a timeout of 3600 seconds and prints a
WARN_ON. So it went ahead to unregister the devlink port. And because
there exists an UNUSED port flavour, we actually re-register the devlink
port as UNUSED.
Commit 08156ba430b4 ("net: dsa: Add devlink port regions support to
DSA") added devlink port regions, which are set up by the driver and not
by DSA.
When we trigger the devlink port deregistration and reregistration as
unused, devlink now prints another WARN_ON, from here:
devlink_port_unregister:
WARN_ON(!list_empty(&devlink_port->region_list));
So the port still has regions, which makes sense, because they were set
up by the driver, and the driver doesn't know we're unregistering the
devlink port.
Somebody needs to tear them down, and optionally (actually it would be
nice, to be consistent) set them up again for the new devlink port.
But DSA's layering stays in our way quite badly here.
The options I've considered are:
1. Introduce a function in devlink to just change a port's type and
flavour. No dice, devlink keeps a lot of state, it really wants the
port to not be registered when you set its parameters, so changing
anything can only be done by destroying what we currently have and
recreating it.
2. Make DSA cache the parameters passed to dsa_devlink_port_region_create,
and the region returned, keep those in a list, then when the devlink
port unregister needs to take place, the existing devlink regions are
destroyed by DSA, and we replay the creation of new regions using the
cached parameters. Problem: mv88e6xxx keeps the region pointers in
chip->ports[port].region, and these will remain stale after DSA frees
them. There are many things DSA can do, but updating mv88e6xxx's
private pointers is not one of them.
3. Just let the driver do it (i.e. introduce a very specific method
called ds->ops->port_reinit_as_unused, which unregisters its devlink
port devlink regions, then the old devlink port, then registers the
new one, then the devlink port regions for it). While it does work,
as opposed to the others, it's pretty horrible from an API
perspective and we can do better.
4. Introduce a new pair of methods, ->port_setup and ->port_teardown,
which in the case of mv88e6xxx must register and unregister the
devlink port regions. Call these 2 methods when the port must be
reinitialized as unused.
Naturally, I went for the 4th approach.
Fixes: 08156ba430b4 ("net: dsa: Add devlink port regions support to DSA")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Lino reports that on his system with bcmgenet as DSA master and KSZ9897
as a switch, rebooting or shutting down never works properly.
What does the bcmgenet driver have special to trigger this, that other
DSA masters do not? It has an implementation of ->shutdown which simply
calls its ->remove implementation. Otherwise said, it unregisters its
network interface on shutdown.
This message can be seen in a loop, and it hangs the reboot process there:
unregister_netdevice: waiting for eth0 to become free. Usage count = 3
So why 3?
A usage count of 1 is normal for a registered network interface, and any
virtual interface which links itself as an upper of that will increment
it via dev_hold. In the case of DSA, this is the call path:
dsa_slave_create
-> netdev_upper_dev_link
-> __netdev_upper_dev_link
-> __netdev_adjacent_dev_insert
-> dev_hold
So a DSA switch with 3 interfaces will result in a usage count elevated
by two, and netdev_wait_allrefs will wait until they have gone away.
Other stacked interfaces, like VLAN, watch NETDEV_UNREGISTER events and
delete themselves, but DSA cannot just vanish and go poof, at most it
can unbind itself from the switch devices, but that must happen strictly
earlier compared to when the DSA master unregisters its net_device, so
reacting on the NETDEV_UNREGISTER event is way too late.
It seems that it is a pretty established pattern to have a driver's
->shutdown hook redirect to its ->remove hook, so the same code is
executed regardless of whether the driver is unbound from the device, or
the system is just shutting down. As Florian puts it, it is quite a big
hammer for bcmgenet to unregister its net_device during shutdown, but
having a common code path with the driver unbind helps ensure it is well
tested.
So DSA, for better or for worse, has to live with that and engage in an
arms race of implementing the ->shutdown hook too, from all individual
drivers, and do something sane when paired with masters that unregister
their net_device there. The only sane thing to do, of course, is to
unlink from the master.
However, complications arise really quickly.
The pattern of redirecting ->shutdown to ->remove is not unique to
bcmgenet or even to net_device drivers. In fact, SPI controllers do it
too (see dspi_shutdown -> dspi_remove), and presumably, I2C controllers
and MDIO controllers do it too (this is something I have not researched
too deeply, but even if this is not the case today, it is certainly
plausible to happen in the future, and must be taken into consideration).
Since DSA switches might be SPI devices, I2C devices, MDIO devices, the
insane implication is that for the exact same DSA switch device, we
might have both ->shutdown and ->remove getting called.
So we need to do something with that insane environment. The pattern
I've come up with is "if this, then not that", so if either ->shutdown
or ->remove gets called, we set the device's drvdata to NULL, and in the
other hook, we check whether the drvdata is NULL and just do nothing.
This is probably not necessary for platform devices, just for devices on
buses, but I would really insist for consistency among drivers, because
when code is copy-pasted, it is not always copy-pasted from the best
sources.
So depending on whether the DSA switch's ->remove or ->shutdown will get
called first, we cannot really guarantee even for the same driver if
rebooting will result in the same code path on all platforms. But
nonetheless, we need to do something minimally reasonable on ->shutdown
too to fix the bug. Of course, the ->remove will do more (a full
teardown of the tree, with all data structures freed, and this is why
the bug was not caught for so long). The new ->shutdown method is kept
separate from dsa_unregister_switch not because we couldn't have
unregistered the switch, but simply in the interest of doing something
quick and to the point.
The big question is: does the DSA switch's ->shutdown get called earlier
than the DSA master's ->shutdown? If not, there is still a risk that we
might still trigger the WARN_ON in unregister_netdevice that says we are
attempting to unregister a net_device which has uppers. That's no good.
Although the reference to the master net_device won't physically go away
even if DSA's ->shutdown comes afterwards, remember we have a dev_hold
on it.
The answer to that question lies in this comment above device_link_add:
* A side effect of the link creation is re-ordering of dpm_list and the
* devices_kset list by moving the consumer device and all devices depending
* on it to the ends of these lists (that does not happen to devices that have
* not been registered when this function is called).
so the fact that DSA uses device_link_add towards its master is not
exactly for nothing. device_shutdown() walks devices_kset from the back,
so this is our guarantee that DSA's shutdown happens before the master's
shutdown.
Fixes: 2f1e8ea726e9 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/
Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
NXP Legal insists that the following are not fine:
- Saying "NXP Semiconductors" instead of "NXP", since the company's
registered name is "NXP"
- Putting a "(c)" sign in the copyright string
- Putting a comma in the copyright string
The only accepted copyright string format is "Copyright <year-range> NXP".
This patch changes the copyright headers in the networking files that
were sent by me, or derived from code sent by me.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Sometimes when unbinding the mv88e6xxx driver on Turris MOX, these error
messages appear:
mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete be:79:b4:9e:9e:96 vid 1 from fdb: -2
mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete be:79:b4:9e:9e:96 vid 0 from fdb: -2
mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 100 from fdb: -2
mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 1 from fdb: -2
mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 0 from fdb: -2
(and similarly for other ports)
What happens is that DSA has a policy "even if there are bugs, let's at
least not leak memory" and dsa_port_teardown() clears the dp->fdbs and
dp->mdbs lists, which are supposed to be empty.
But deleting that cleanup code, the warnings go away.
=> the FDB and MDB lists (used for refcounting on shared ports, aka CPU
and DSA ports) will eventually be empty, but are not empty by the time
we tear down those ports. Aka we are deleting them too soon.
The addresses that DSA complains about are host-trapped addresses: the
local addresses of the ports, and the MAC address of the bridge device.
The problem is that offloading those entries happens from a deferred
work item scheduled by the SWITCHDEV_FDB_DEL_TO_DEVICE handler, and this
races with the teardown of the CPU and DSA ports where the refcounting
is kept.
In fact, not only it races, but fundamentally speaking, if we iterate
through the port list linearly, we might end up tearing down the shared
ports even before we delete a DSA user port which has a bridge upper.
So as it turns out, we need to first tear down the user ports (and the
unused ones, for no better place of doing that), then the shared ports
(the CPU and DSA ports). In between, we need to ensure that all work
items scheduled by our switchdev handlers (which only run for user
ports, hence the reason why we tear them down first) have finished.
Fixes: 161ca59d39e9 ("net: dsa: reference count the MDB entries at the cross-chip notifier level")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210914134726.2305133-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
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 <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/20210914134331.2303380-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
I noticed that only port 0 worked on the RTL8366RB since we
started to use custom tags.
It turns out that the format of egress custom tags is actually
different from ingress custom tags. While the lower bits just
contain the port number in ingress tags, egress tags need to
indicate destination port by setting the bit for the
corresponding port.
It was working on port 0 because port 0 added 0x00 as port
number in the lower bits, and if you do this the packet appears
at all ports, including the intended port. Ooops.
Fix this and all ports work again. Use the define for shifting
the "type A" into place while we're at it.
Tested on the D-Link DIR-685 by sending traffic to each of
the ports in turn. It works.
Fixes: 86dd9868b878 ("net: dsa: tag_rtl4_a: Support also egress tags")
Cc: DENG Qingfang <dqfext@gmail.com>
Cc: Mauri Sandberg <sandberg@mailfence.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Introduced in commit 38b5beeae7a4 ("net: dsa: sja1105: prepare tagger
for handling DSA tags and VLAN simultaneously"), the sja1105_xmit_tpid
function solved quite a different problem than our needs are now.
Then, we used best-effort VLAN filtering and we were using the xmit_tpid
to tunnel packets coming from an 8021q upper through the TX VLAN allocated
by tag_8021q to that egress port. The need for a different VLAN protocol
depending on switch revision came from the fact that this in itself was
more of a hack to trick the hardware into accepting tunneled VLANs in
the first place.
Right now, we deny 8021q uppers (see sja1105_prechangeupper). Even if we
supported them again, we would not do that using the same method of
{tunneling the VLAN on egress, retagging the VLAN on ingress} that we
had in the best-effort VLAN filtering mode. It seems rather simpler that
we just allocate a VLAN in the VLAN table that is simply not used by the
bridge at all, or by any other port.
Anyway, I have 2 gripes with the current sja1105_xmit_tpid:
1. When sending packets on behalf of a VLAN-aware bridge (with the new
TX forwarding offload framework) plus untagged (with the tag_8021q
VLAN added by the tagger) packets, we can see that on SJA1105P/Q/R/S
and later (which have a qinq_tpid of ETH_P_8021AD), some packets sent
through the DSA master have a VLAN protocol of 0x8100 and others of
0x88a8. This is strange and there is no reason for it now. If we have
a bridge and are therefore forced to send using that bridge's TPID,
we can as well blend with that bridge's VLAN protocol for all packets.
2. The sja1105_xmit_tpid introduces a dependency on the sja1105 driver,
because it looks inside dp->priv. It is desirable to keep as much
separation between taggers and switch drivers as possible. Now it
doesn't do that anymore.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The sja1105 driver is a bit special in its use of VLAN headers as DSA
tags. This is because in VLAN-aware mode, the VLAN headers use an actual
TPID of 0x8100, which is understood even by the DSA master as an actual
VLAN header.
Furthermore, control packets such as PTP and STP are transmitted with no
VLAN header as a DSA tag, because, depending on switch generation, there
are ways to steer these control packets towards a precise egress port
other than VLAN tags. Transmitting control packets as untagged means
leaving a door open for traffic in general to be transmitted as untagged
from the DSA master, and for it to traverse the switch and exit a random
switch port according to the FDB lookup.
This behavior is a bit out of line with other DSA drivers which have
native support for DSA tagging. There, it is to be expected that the
switch only accepts DSA-tagged packets on its CPU port, dropping
everything that does not match this pattern.
We perhaps rely a bit too much on the switches' hardware dropping on the
CPU port, and place no other restrictions in the kernel data path to
avoid that. For example, sja1105 is also a bit special in that STP/PTP
packets are transmitted using "management routes"
(sja1105_port_deferred_xmit): when sending a link-local packet from the
CPU, we must first write a SPI message to the switch to tell it to
expect a packet towards multicast MAC DA 01-80-c2-00-00-0e, and to route
it towards port 3 when it gets it. This entry expires as soon as it
matches a packet received by the switch, and it needs to be reinstalled
for the next packet etc. All in all quite a ghetto mechanism, but it is
all that the sja1105 switches offer for injecting a control packet.
The driver takes a mutex for serializing control packets and making the
pairs of SPI writes of a management route and its associated skb atomic,
but to be honest, a mutex is only relevant as long as all parties agree
to take it. With the DSA design, it is possible to open an AF_PACKET
socket on the DSA master net device, and blast packets towards
01-80-c2-00-00-0e, and whatever locking the DSA switch driver might use,
it all goes kaput because management routes installed by the driver will
match skbs sent by the DSA master, and not skbs generated by the driver
itself. So they will end up being routed on the wrong port.
So through the lens of that, maybe it would make sense to avoid that
from happening by doing something in the network stack, like: introduce
a new bit in struct sk_buff, like xmit_from_dsa. Then, somewhere around
dev_hard_start_xmit(), introduce the following check:
if (netdev_uses_dsa(dev) && !skb->xmit_from_dsa)
kfree_skb(skb);
Ok, maybe that is a bit drastic, but that would at least prevent a bunch
of problems. For example, right now, even though the majority of DSA
switches drop packets without DSA tags sent by the DSA master (and
therefore the majority of garbage that user space daemons like avahi and
udhcpcd and friends create), it is still conceivable that an aggressive
user space program can open an AF_PACKET socket and inject a spoofed DSA
tag directly on the DSA master. We have no protection against that; the
packet will be understood by the switch and be routed wherever user
space says. Furthermore: there are some DSA switches where we even have
register access over Ethernet, using DSA tags. So even user space
drivers are possible in this way. This is a huge hole.
However, the biggest thing that bothers me is that udhcpcd attempts to
ask for an IP address on all interfaces by default, and with sja1105, it
will attempt to get a valid IP address on both the DSA master as well as
on sja1105 switch ports themselves. So with IP addresses in the same
subnet on multiple interfaces, the routing table will be messed up and
the system will be unusable for traffic until it is configured manually
to not ask for an IP address on the DSA master itself.
It turns out that it is possible to avoid that in the sja1105 driver, at
least very superficially, by requesting the switch to drop VLAN-untagged
packets on the CPU port. With the exception of control packets, all
traffic originated from tag_sja1105.c is already VLAN-tagged, so only
STP and PTP packets need to be converted. For that, we need to uphold
the equivalence between an untagged and a pvid-tagged packet, and to
remember that the CPU port of sja1105 uses a pvid of 4095.
Now that we drop untagged traffic on the CPU port, non-aggressive user
space applications like udhcpcd stop bothering us, and sja1105 effectively
becomes just as vulnerable to the aggressive kind of user space programs
as other DSA switches are (ok, users can also create 8021q uppers on top
of the DSA master in the case of sja1105, but in future patches we can
easily deny that, but it still doesn't change the fact that VLAN-tagged
packets can still be injected over raw sockets).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
As explained in commit e358bef7c392 ("net: dsa: Give drivers the chance
to veto certain upper devices"), the hellcreek driver uses some tricks
to comply with the network stack expectations: it enforces port
separation in standalone mode using VLANs. For untagged traffic,
bridging between ports is prevented by using different PVIDs, and for
VLAN-tagged traffic, it never accepts 8021q uppers with the same VID on
two ports, so packets with one VLAN cannot leak from one port to another.
That is almost fine*, and has worked because hellcreek relied on an
implicit behavior of the DSA core that was changed by the previous
patch: the standalone ports declare the 'rx-vlan-filter' feature as 'on
[fixed]'. Since most of the DSA drivers are actually VLAN-unaware in
standalone mode, that feature was actually incorrectly reflecting the
hardware/driver state, so there was a desire to fix it. This leaves the
hellcreek driver in a situation where it has to explicitly request this
behavior from the DSA framework.
We configure the ports as follows:
- Standalone: 'rx-vlan-filter' is on. An 8021q upper on top of a
standalone hellcreek port will go through dsa_slave_vlan_rx_add_vid
and will add a VLAN to the hardware tables, giving the driver the
opportunity to refuse it through .port_prechangeupper.
- Bridged with vlan_filtering=0: 'rx-vlan-filter' is off. An 8021q upper
on top of a bridged hellcreek port will not go through
dsa_slave_vlan_rx_add_vid, because there will not be any attempt to
offload this VLAN. The driver already disables VLAN awareness, so that
upper should receive the traffic it needs.
- Bridged with vlan_filtering=1: 'rx-vlan-filter' is on. An 8021q upper
on top of a bridged hellcreek port will call dsa_slave_vlan_rx_add_vid,
and can again be vetoed through .port_prechangeupper.
*It is not actually completely fine, because if I follow through
correctly, we can have the following situation:
ip link add br0 type bridge vlan_filtering 0
ip link set lan0 master br0 # lan0 now becomes VLAN-unaware
ip link set lan0 nomaster # lan0 fails to become VLAN-aware again, therefore breaking isolation
This patch fixes that corner case by extending the DSA core logic, based
on this requested attribute, to change the VLAN awareness state of the
switch (port) when it leaves the bridge.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
There have been multiple independent reports about
dsa_slave_vlan_rx_add_vid being called (and consequently calling the
drivers' .port_vlan_add) when it isn't needed, and sometimes (not
always) causing problems in the process.
Case 1:
mv88e6xxx_port_vlan_prepare is stubborn and only accepts VLANs on
bridged ports. That is understandably so, because standalone mv88e6xxx
ports are VLAN-unaware, and VTU entries are said to be a scarce
resource.
Otherwise said, the following fails lamentably on mv88e6xxx:
ip link add br0 type bridge vlan_filtering 1
ip link set lan3 master br0
ip link add link lan10 name lan10.1 type vlan id 1
[485256.724147] mv88e6085 d0032004.mdio-mii:12: p10: hw VLAN 1 already used by port 3 in br0
RTNETLINK answers: Operation not supported
This has become a worse issue since commit 9b236d2a69da ("net: dsa:
Advertise the VLAN offload netdev ability only if switch supports it").
Up to that point, the driver was returning -EOPNOTSUPP and DSA was
reconverting that error to 0, making the 8021q upper think all is ok
(but obviously the error message was there even prior to this change).
After that change the -EOPNOTSUPP is propagated to vlan_vid_add, and it
is a hard error.
Case 2:
Ports that don't offload the Linux bridge (have a dp->bridge_dev = NULL
because they don't implement .port_bridge_{join,leave}). Understandably,
a standalone port should not offload VLANs either, it should remain VLAN
unaware and any VLAN should be a software VLAN (as long as the hardware
is not quirky, that is).
In fact, dsa_slave_port_obj_add does do the right thing and rejects
switchdev VLAN objects coming from the bridge when that bridge is not
offloaded:
case SWITCHDEV_OBJ_ID_PORT_VLAN:
if (!dsa_port_offloads_bridge_port(dp, obj->orig_dev))
return -EOPNOTSUPP;
err = dsa_slave_vlan_add(dev, obj, extack);
But it seems that the bridge is able to trick us. The __vlan_vid_add
from br_vlan.c has:
/* Try switchdev op first. In case it is not supported, fallback to
* 8021q add.
*/
err = br_switchdev_port_vlan_add(dev, v->vid, flags, extack);
if (err == -EOPNOTSUPP)
return vlan_vid_add(dev, br->vlan_proto, v->vid);
So it says "no, no, you need this VLAN in your life!". And we, naive as
we are, say "oh, this comes from the vlan_vid_add code path, it must be
an 8021q upper, sure, I'll take that". And we end up with that bridge
VLAN installed on our port anyway. But this time, it has the wrong flags:
if the bridge was trying to install VLAN 1 as a pvid/untagged VLAN,
failed via switchdev, retried via vlan_vid_add, we have this comment:
/* This API only allows programming tagged, non-PVID VIDs */
So what we do makes absolutely no sense.
Backtracing a bit, we see the common pattern. We allow the network stack
to think that our standalone ports are VLAN-aware, but they aren't, for
the vast majority of switches. The quirky ones should not dictate the
norm. The dsa_slave_vlan_rx_add_vid and dsa_slave_vlan_rx_kill_vid
methods exist for drivers that need the 'rx-vlan-filter: on' feature in
ethtool -k, which can be due to any of the following reasons:
1. vlan_filtering_is_global = true, and some ports are under a
VLAN-aware bridge while others are standalone, and the standalone
ports would otherwise drop VLAN-tagged traffic. This is described in
commit 061f6a505ac3 ("net: dsa: Add ndo_vlan_rx_{add, kill}_vid
implementation").
2. the ports that are under a VLAN-aware bridge should also set this
feature, for 8021q uppers having a VID not claimed by the bridge.
In this case, the driver will essentially not even know that the VID
is coming from the 8021q layer and not the bridge.
3. Hellcreek. This driver needs it because in standalone mode, it uses
unique VLANs per port to ensure separation. For separation of untagged
traffic, it uses different PVIDs for each port, and for separation of
VLAN-tagged traffic, it never accepts 8021q uppers with the same vid
on two ports.
If a driver does not fall under any of the above 3 categories, there is
no reason why it should advertise the 'rx-vlan-filter' feature, therefore
no reason why it should offload the VLANs added through vlan_vid_add.
This commit fixes the problem by removing the 'rx-vlan-filter' feature
from the slave devices when they operate in standalone mode, and when
they offload a VLAN-unaware bridge.
The way it works is that vlan_vid_add will now stop its processing here:
vlan_add_rx_filter_info:
if (!vlan_hw_filter_capable(dev, proto))
return 0;
So the VLAN will still be saved in the interface's VLAN RX filtering
list, but because it does not declare VLAN filtering in its features,
the 8021q module will return zero without committing that VLAN to
hardware.
This gives the drivers what they want, since it keeps the 8021q VLANs
away from the VLAN table until VLAN awareness is enabled (point at which
the ports are no longer standalone, hence in the mv88e6xxx case, the
check in mv88e6xxx_port_vlan_prepare passes).
Since the issue predates the existence of the hellcreek driver, case 3
will be dealt with in a separate patch.
The main change that this patch makes is to no longer set
NETIF_F_HW_VLAN_CTAG_FILTER unconditionally, but toggle it dynamically
(for most switches, never).
The second part of the patch addresses an issue that the first part
introduces: because the 'rx-vlan-filter' feature is now dynamically
toggled, and our .ndo_vlan_rx_add_vid does not get called when
'rx-vlan-filter' is off, we need to avoid bugs such as the following by
replaying the VLANs from 8021q uppers every time we enable VLAN
filtering:
ip link add link lan0 name lan0.100 type vlan id 100
ip addr add 192.168.100.1/24 dev lan0.100
ping 192.168.100.2 # should work
ip link add br0 type bridge vlan_filtering 0
ip link set lan0 master br0
ping 192.168.100.2 # should still work
ip link set br0 type bridge vlan_filtering 1
ping 192.168.100.2 # should still work but doesn't
As reported by Florian, some drivers look at ds->vlan_filtering in
their .port_vlan_add() implementation. So this patch also makes sure
that ds->vlan_filtering is committed before calling the driver. This is
the reason why it is first committed, then restored on the failure path.
Reported-by: Tobias Waldekranz <tobias@waldekranz.com>
Reported-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
If the driver does not implement .port_bridge_{join,leave}, then we must
fall back to standalone operation on that port, and trigger the error
path of dsa_port_bridge_join. This sets dp->bridge_dev = NULL.
In turn, having a non-NULL dp->bridge_dev when there is no offloading
support makes the following things go wrong:
- dsa_default_offload_fwd_mark make the wrong decision in setting
skb->offload_fwd_mark. It should set skb->offload_fwd_mark = 0 for
ports that don't offload the bridge, which should instruct the bridge
to forward in software. But this does not happen, dp->bridge_dev is
incorrectly set to point to the bridge, so the bridge is told that
packets have been forwarded in hardware, which they haven't.
- switchdev objects (MDBs, VLANs) should not be offloaded by ports that
don't offload the bridge. Standalone ports should behave as packet-in,
packet-out and the bridge should not be able to manipulate the pvid of
the port, or tag stripping on egress, or ingress filtering. This
should already work fine because dsa_slave_port_obj_add has:
case SWITCHDEV_OBJ_ID_PORT_VLAN:
if (!dsa_port_offloads_bridge_port(dp, obj->orig_dev))
return -EOPNOTSUPP;
err = dsa_slave_vlan_add(dev, obj, extack);
but since dsa_port_offloads_bridge_port works based on dp->bridge_dev,
this is again sabotaging us.
All the above work in case the port has an unoffloaded LAG interface, so
this is well exercised code, we should apply it for plain unoffloaded
bridge ports too.
Reported-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
ports
For ports that have a NULL dp->bridge_dev, dsa_port_to_bridge_port()
also returns NULL as expected.
Issue #1 is that we are performing a NULL pointer dereference on brport_dev.
Issue #2 is that these are ports on which switchdev_bridge_port_offload
has not been called, so we should not call switchdev_bridge_port_unoffload
on them either.
Both issues are addressed by checking against a NULL brport_dev in
dsa_port_pre_bridge_leave and exiting early.
Fixes: 2f5dc00f7a3e ("net: bridge: switchdev: let drivers inform which bridge ports are offloaded")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Right now, cross-tree bridging setups work somewhat by mistake.
In the case of cross-tree bridging with sja1105, all switch instances
need to agree upon a common VLAN ID for forwarding a packet that belongs
to a certain bridging domain.
With TX forwarding offload, the VLAN ID is the bridge VLAN for
VLAN-aware bridging, and the tag_8021q TX forwarding offload VID
(a VLAN which has non-zero VBID bits) for VLAN-unaware bridging.
The VBID for VLAN-unaware bridging is derived from the dp->bridge_num
value calculated by DSA independently for each switch tree.
If ports from one tree join one bridge, and ports from another tree join
another bridge, DSA will assign them the same bridge_num, even though
the bridges are different. If cross-tree bridging is supported, this
is an issue.
Modify DSA to calculate the bridge_num globally across all switch trees.
This has the implication for a driver that the dp->bridge_num value that
DSA will assign to its ports might not be contiguous, if there are
boards with multiple DSA drivers instantiated. Additionally, all
bridge_num values eat up towards each switch's
ds->num_fwd_offloading_bridges maximum, which is potentially unfortunate,
and can be seen as a limitation introduced by this patch. However, that
is the lesser evil for now.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Add support for tag_sja1105 running on non-sja1105 DSA ports, by making
sure that every time we dereference dp->priv, we check the switch's
dsa_switch_ops (otherwise we access a struct sja1105_port structure that
is in fact something else).
This adds an unconditional build-time dependency between sja1105 being
built as module => tag_sja1105 must also be built as module. This was
there only for PTP before.
Some sane defaults must also take place when not running on sja1105
hardware. These are:
- sja1105_xmit_tpid: the sja1105 driver uses different VLAN protocols
depending on VLAN awareness and switch revision (when an encapsulated
VLAN must be sent). Default to 0x8100.
- sja1105_rcv_meta_state_machine: this aggregates PTP frames with their
metadata timestamp frames. When running on non-sja1105 hardware, don't
do that and accept all frames unmodified.
- sja1105_defer_xmit: calls sja1105_port_deferred_xmit in sja1105_main.c
which writes a management route over SPI. When not running on sja1105
hardware, bypass the SPI write and send the frame as-is.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
During the development of the blamed patch, the "bool broadcast"
argument of dsa_port_tag_8021q_vlan_{add,del} was originally called
"bool local", and the meaning was the exact opposite.
Due to a rookie mistake where the patch was modified at the last minute
without retesting, the instances of dsa_port_tag_8021q_vlan_{add,del}
are called with the wrong values. During setup and teardown, cross-chip
notifiers should not be broadcast to all DSA trees, while during
bridging, they should.
Fixes: 724395f4dc95 ("net: dsa: tag_8021q: don't broadcast during setup/teardown")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Conflicts:
drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h
9e26680733d5 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp")
9e518f25802c ("bnxt_en: 1PPS functions to configure TSIO pins")
099fdeda659d ("bnxt_en: Event handler for PPS events")
kernel/bpf/helpers.c
include/linux/bpf-cgroup.h
a2baf4e8bb0f ("bpf: Fix potentially incorrect results with bpf_get_local_storage()")
c7603cfa04e7 ("bpf: Add ambient BPF runtime context stored in current")
drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
5957cc557dc5 ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray")
2d0b41a37679 ("net/mlx5: Refcount mlx5_irq with integer")
MAINTAINERS
7b637cd52f02 ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo")
7d901a1e878a ("net: phy: add Maxlinear GPY115/21x/24x driver")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Currently, on my board with multiple sja1105 switches in disjoint trees
described in commit f66a6a69f97a ("net: dsa: permit cross-chip bridging
between all trees in the system"), rebooting the board triggers the
following benign warnings:
[ 12.345566] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 1088 deletion: -ENOENT
[ 12.353804] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 2112 deletion: -ENOENT
[ 12.362019] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 1089 deletion: -ENOENT
[ 12.370246] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 2113 deletion: -ENOENT
[ 12.378466] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 1090 deletion: -ENOENT
[ 12.386683] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 2114 deletion: -ENOENT
Basically switch 1 calls dsa_tag_8021q_unregister, and switch 1's TX and
RX VLANs cannot be found on switch 2's CPU port.
But why would switch 2 even attempt to delete switch 1's TX and RX
tag_8021q VLANs from its CPU port? Well, because we use dsa_broadcast,
and it is supposed that it had added those VLANs in the first place
(because in dsa_port_tag_8021q_vlan_match, all CPU ports match
regardless of their tree index or switch index).
The two trees probe asynchronously, and when switch 1 probed, it called
dsa_broadcast which did not notify the tree of switch 2, because that
didn't probe yet. But during unbind, switch 2's tree _is_ probed, so it
_is_ notified of the deletion.
Before jumping to introduce a synchronization mechanism between the
probing across disjoint switch trees, let's take a step back and see
whether we _need_ to do that in the first place.
The RX and TX VLANs of switch 1 would be needed on switch 2's CPU port
only if switch 1 and 2 were part of a cross-chip bridge. And
dsa_tag_8021q_bridge_join takes care precisely of that (but if probing
was synchronous, the bridge_join would just end up bumping the VLANs'
refcount, because they are already installed by the setup path).
Since by the time the ports are bridged, all DSA trees are already set
up, and we don't need the tag_8021q VLANs of one switch installed on the
other switches during probe time, the answer is that we don't need to
fix the synchronization issue.
So make the setup and teardown code paths call dsa_port_notify, which
notifies only the local tree, and the bridge code paths call
dsa_broadcast, which let the other trees know as well.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Currently this error message does not say a lot:
[ 32.693498] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT
[ 32.699725] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT
[ 32.705931] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT
[ 32.712139] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT
[ 32.718347] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT
[ 32.724554] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT
but in this form, it is immediately obvious (at least to me) what the
problem is, even without further looking at the code:
[ 12.345566] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 1088 deletion: -ENOENT
[ 12.353804] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 2112 deletion: -ENOENT
[ 12.362019] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 1089 deletion: -ENOENT
[ 12.370246] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 2113 deletion: -ENOENT
[ 12.378466] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 1090 deletion: -ENOENT
[ 12.386683] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 2114 deletion: -ENOENT
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Create a similar helper for locating the offset to the DSA header
relative to skb->data, and make the existing EtherType header taggers to
use it.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
It seems that protocol tagging driver writers are always surprised about
the formula they use to reach their EtherType header on RX, which
becomes apparent from the fact that there are comments in multiple
drivers that mention the same information.
Create a helper that returns a void pointer to skb->data - 2, as well as
centralize the explanation why that is the case.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Hide away the memmove used by DSA EtherType header taggers to shift the
MAC SA and DA to the left to make room for the header, after they've
called skb_push(). The call to skb_push() is still left explicit in
drivers, to be symmetric with dsa_strip_etype_header, and because not
all callers can be refactored to do it (for example, brcm_tag_xmit_ll
has common code for a pre-Ethernet DSA tag and an EtherType DSA tag).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
All header taggers open-code a memmove that is fairly not all that
obvious, and we can hide the details behind a helper function, since the
only thing specific to the driver is the length of the header tag.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
by drivers towards the bridge
The blamed commit added a new field to struct switchdev_notifier_fdb_info,
but did not make sure that all call paths set it to something valid.
For example, a switchdev driver may emit a SWITCHDEV_FDB_ADD_TO_BRIDGE
notifier, and since the 'is_local' flag is not set, it contains junk
from the stack, so the bridge might interpret those notifications as
being for local FDB entries when that was not intended.
To avoid that now and in the future, zero-initialize all
switchdev_notifier_fdb_info structures created by drivers such that all
newly added fields to not need to touch drivers again.
Fixes: 2c4eca3ef716 ("net: bridge: switchdev: include local flag in FDB notifications")
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Karsten Graul <kgraul@linux.ibm.com>
Link: https://lore.kernel.org/r/20210810115024.1629983-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
All kernel devlink implementations call to devlink_alloc() during
initialization routine for specific device which is used later as
a parent device for devlink_register().
Such late device assignment causes to the situation which requires us to
call to device_register() before setting other parameters, but that call
opens devlink to the world and makes accessible for the netlink users.
Any attempt to move devlink_register() to be the last call generates the
following error due to access to the devlink->dev pointer.
[ 8.758862] devlink_nl_param_fill+0x2e8/0xe50
[ 8.760305] devlink_param_notify+0x6d/0x180
[ 8.760435] __devlink_params_register+0x2f1/0x670
[ 8.760558] devlink_params_register+0x1e/0x20
The simple change of API to set devlink device in the devlink_alloc()
instead of devlink_register() fixes all this above and ensures that
prior to call to devlink_register() everything already set.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Drivers that support both the toggling of address learning and dynamic
FDB flushing (mv88e6xxx, b53, sja1105) currently need to fast-age a port
twice when it leaves a bridge:
- once, when del_nbp() calls br_stp_disable_port() which puts the port
in the BLOCKING state
- twice, when dsa_port_switchdev_unsync_attrs() calls
dsa_port_clear_brport_flags() which disables address learning
The knee-jerk reaction might be to say "dsa_port_clear_brport_flags does
not need to fast-age the port at all", but the thing is, we still need
both code paths to flush the dynamic FDB entries in different situations.
When a DSA switch port leaves a bonding/team interface that is (still) a
bridge port, no del_nbp() will be called, so we rely on
dsa_port_clear_brport_flags() function to restore proper standalone port
functionality with address learning disabled.
So the solution is just to avoid double the work when both code paths
are called in series. Luckily, DSA already caches the STP port state, so
we can skip flushing the dynamic FDB when we disable address learning
and the STP state is one where no address learning takes place at all.
Under that condition, not flushing the FDB is safe because there is
supposed to not be any dynamic FDB entry at all (they were flushed
during the transition towards that state, and none were learned in the
meanwhile).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Commit 39f32101543b ("net: dsa: don't fast age standalone ports")
assumed that all standalone ports disable address learning, but if the
switch driver implements .port_fast_age but not .port_bridge_flags (like
ksz9477, ksz8795, lantiq_gswip, lan9303), then that might not actually
be true.
So whereas before, the bridge temporarily walking us through the
BLOCKING STP state meant that the standalone ports had a checkpoint to
flush their baggage and start fresh when they join a bridge, after that
commit they no longer do.
Restore the old behavior for these drivers by checking if the switch can
toggle address learning. If it can't, disregard the "do_fast_age"
argument and unconditionally perform fast ageing on STP state changes.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Currently, when DSA performs fast ageing on a port, 'bridge fdb' shows
us that the 'self' entries (corresponding to the hardware bridge, as
printed by dsa_slave_fdb_dump) are deleted, but the 'master' entries
(corresponding to the software bridge) aren't.
Indeed, searching through the bridge driver, neither the
brport_attr_learning handler nor the IFLA_BRPORT_LEARNING handler call
br_fdb_delete_by_port. However, br_stp_disable_port does, which is one
of the paths which DSA uses to trigger a fast ageing process anyway.
There is, however, one other very promising caller of
br_fdb_delete_by_port, and that is the bridge driver's handler of the
SWITCHDEV_FDB_FLUSH_TO_BRIDGE atomic notifier. Currently the s390/qeth
HiperSockets card driver is the only user of this.
I can't say I understand that driver's architecture or interaction with
the bridge, but it appears to not be a switchdev driver in the traditional
sense of the word. Nonetheless, the mechanism it provides is a useful
way for DSA to express the fact that it performs fast ageing too, in a
way that does not change the existing behavior for other drivers.
Cc: Alexandra Winter <wintera@linux.ibm.com>
Cc: Julian Wiedmann <jwi@linux.ibm.com>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
On topology changes, stations that were dynamically learned on ports
that are no longer part of the active topology must be flushed - this is
described by clause "17.11 Updating learned station location information"
of IEEE 802.1D-2004.
However, when address learning on the bridge port is turned off in the
first place, there is nothing to flush, so skip a potentially expensive
operation.
We can finally do this now since DSA is aware of the learning state of
its bridged ports.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Currently DSA leaves it down to device drivers to fast age the FDB on a
port when address learning is disabled on it. There are 2 reasons for
doing that in the first place:
- when address learning is disabled by user space, through
IFLA_BRPORT_LEARNING or the brport_attr_learning sysfs, what user
space typically wants to achieve is to operate in a mode with no
dynamic FDB entry on that port. But if the port is already up, some
addresses might have been already learned on it, and it seems silly to
wait for 5 minutes for them to expire until something useful can be
done.
- when a port leaves a bridge and becomes standalone, DSA turns off
address learning on it. This also has the nice side effect of flushing
the dynamically learned bridge FDB entries on it, which is a good idea
because standalone ports should not have bridge FDB entries on them.
We let drivers manage fast ageing under this condition because if DSA
were to do it, it would need to track each port's learning state, and
act upon the transition, which it currently doesn't.
But there are 2 reasons why doing it is better after all:
- drivers might get it wrong and not do it (see b53_port_set_learning)
- we would like to flush the dynamic entries from the software bridge
too, and letting drivers do that would be another pain point
So track the port learning state and trigger a fast age process
automatically within DSA.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
DSA drives the procedure to flush dynamic FDB entries from a port based
on the change of STP state: whenever we go from a state where address
learning is enabled (LEARNING, FORWARDING) to a state where it isn't
(LISTENING, BLOCKING, DISABLED), we need to flush the existing dynamic
entries.
However, there are cases when this is not needed. Internally, when a
DSA switch interface is not under a bridge, DSA still keeps it in the
"FORWARDING" STP state. And when that interface joins a bridge, the
bridge will meticulously iterate that port through all STP states,
starting with BLOCKING and ending with FORWARDING. Because there is a
state transition from the standalone version of FORWARDING into the
temporary BLOCKING bridge port state, DSA calls the fast age procedure.
Since commit 5e38c15856e9 ("net: dsa: configure better brport flags when
ports leave the bridge"), DSA asks standalone ports to disable address
learning. Therefore, there can be no dynamic FDB entries on a standalone
port. Therefore, it does not make sense to flush dynamic FDB entries on
one.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
querier
Commit 08cc83cc7fd8 ("net: dsa: add support for BRIDGE_MROUTER
attribute") added an option for users to turn off multicast flooding
towards the CPU if they turn off the IGMP querier on a bridge which
already has enslaved ports (echo 0 > /sys/class/net/br0/bridge/multicast_router).
And commit a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags")
simply papered over that issue, because it moved the decision to flood
the CPU with multicast (or not) from the DSA core down to individual drivers,
instead of taking a more radical position then.
The truth is that disabling multicast flooding to the CPU is simply
something we are not prepared to do now, if at all. Some reasons:
- ICMP6 neighbor solicitation messages are unregistered multicast
packets as far as the bridge is concerned. So if we stop flooding
multicast, the outside world cannot ping the bridge device's IPv6
link-local address.
- There might be foreign interfaces bridged with our DSA switch ports
(sending a packet towards the host does not necessarily equal
termination, but maybe software forwarding). So if there is no one
interested in that multicast traffic in the local network stack, that
doesn't mean nobody is.
- PTP over L4 (IPv4, IPv6) is multicast, but is unregistered as far as
the bridge is concerned. This should reach the CPU port.
- The switch driver might not do FDB partitioning. And since we don't
even bother to do more fine-grained flood disabling (such as "disable
flooding _from_port_N_ towards the CPU port" as opposed to "disable
flooding _from_any_port_ towards the CPU port"), this breaks standalone
ports, or even multiple bridges where one has an IGMP querier and one
doesn't.
Reverting the logic makes all of the above work.
Fixes: a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags")
Fixes: 08cc83cc7fd8 ("net: dsa: add support for BRIDGE_MROUTER attribute")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Qingfang points out that when a bridge with the default settings is
created and a port joins it:
ip link add br0 type bridge
ip link set swp0 master br0
DSA calls br_multicast_router() on the bridge to see if the br0 device
is a multicast router port, and if it is, it enables multicast flooding
to the CPU port, otherwise it disables it.
If we look through the multicast_router_show() sysfs or at the
IFLA_BR_MCAST_ROUTER netlink attribute, we see that the default mrouter
attribute for the bridge device is "1" (MDB_RTR_TYPE_TEMP_QUERY).
However, br_multicast_router() will return "0" (MDB_RTR_TYPE_DISABLED),
because an mrouter port in the MDB_RTR_TYPE_TEMP_QUERY state may not be
actually _active_ until it receives an actual IGMP query. So, the
br_multicast_router() function should really have been called
br_multicast_router_active() perhaps.
When/if an IGMP query is received, the bridge device will transition via
br_multicast_mark_router() into the active state until the
ip4_mc_router_timer expires after an multicast_querier_interval.
Of course, this does not happen if the bridge is created with an
mcast_router attribute of "2" (MDB_RTR_TYPE_PERM).
The point is that in lack of any IGMP query messages, and in the default
bridge configuration, unregistered multicast packets will not be able to
reach the CPU port through flooding, and this breaks many use cases
(most obviously, IPv6 ND, with its ICMP6 neighbor solicitation multicast
messages).
Leave the multicast flooding setting towards the CPU port down to a driver
level decision.
Fixes: 010e269f91be ("net: dsa: sync up switchdev objects and port attributes when joining the bridge")
Reported-by: DENG Qingfang <dqfext@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
module if PTP is enabled
TX timestamps are sent by SJA1110 as Ethernet packets containing
metadata, so they are received by the tagging driver but must be
processed by the switch driver - the one that is stateful since it
keeps the TX timestamp queue.
This means that there is an sja1110_process_meta_tstamp() symbol
exported by the switch driver which is called by the tagging driver.
There is a shim definition for that function when the switch driver is
not compiled, which does nothing, but that shim is not effective when
the tagging protocol driver is built-in and the switch driver is a
module, because built-in code cannot call symbols exported by modules.
So add an optional dependency between the tagger and the switch driver,
if PTP support is enabled in the switch driver. If PTP is not enabled,
sja1110_process_meta_tstamp() will translate into the shim "do nothing
with these meta frames" function.
Fixes: 566b18c8b752 ("net: dsa: sja1105: implement TX timestamping for SJA1110")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Be there an "H" switch topology, where there are 2 switches connected as
follows:
eth0 eth1
| |
CPU port CPU port
| DSA link |
sw0p0 sw0p1 sw0p2 sw0p3 sw0p4 -------- sw1p4 sw1p3 sw1p2 sw1p1 sw1p0
| | | | | |
user user user user user user
port port port port port port
basically one where each switch has its own CPU port for termination,
but there is also a DSA link in case packets need to be forwarded in
hardware between one switch and another.
DSA insists to see this as a daisy chain topology, basically registering
all network interfaces as sw0p0@eth0, ... sw1p0@eth0 and disregarding
eth1 as a valid DSA master.
This is only half the story, since when asked using dsa_port_is_cpu(),
DSA will respond that sw1p1 is a CPU port, however one which has no
dp->cpu_dp pointing to it. So sw1p1 is enabled, but not used.
Furthermore, be there a driver for switches which support only one
upstream port. This driver iterates through its ports and checks using
dsa_is_upstream_port() whether the current port is an upstream one.
For switch 1, two ports pass the "is upstream port" checks:
- sw1p4 is an upstream port because it is a routing port towards the
dedicated CPU port assigned using dsa_tree_setup_default_cpu()
- sw1p1 is also an upstream port because it is a CPU port, albeit one
that is disabled. This is because dsa_upstream_port() returns:
if (!cpu_dp)
return port;
which means that if @dp does not have a ->cpu_dp pointer (which is a
characteristic of CPU ports themselves as well as unused ports), then
@dp is its own upstream port.
So the driver for switch 1 rightfully says: I have two upstream ports,
but I don't support multiple upstream ports! So let me error out, I
don't know which one to choose and what to do with the other one.
Generally I am against enforcing any default policy in the kernel in
terms of user to CPU port assignment (like round robin or such) but this
case is different. To solve the conundrum, one would have to:
- Disable sw1p1 in the device tree or mark it as "not a CPU port" in
order to comply with DSA's view of this topology as a daisy chain,
where the termination traffic from switch 1 must pass through switch 0.
This is counter-productive because it wastes 1Gbps of termination
throughput in switch 1.
- Disable the DSA link between sw0p4 and sw1p4 and do software
forwarding between switch 0 and 1, and basically treat the switches as
part of disjoint switch trees. This is counter-productive because it
wastes 1Gbps of autonomous forwarding throughput between switch 0 and 1.
- Treat sw0p4 and sw1p4 as user ports instead of DSA links. This could
work, but it makes cross-chip bridging impossible. In this setup we
would need to have 2 separate bridges, br0 spanning the ports of
switch 0, and br1 spanning the ports of switch 1, and the "DSA links
treated as user ports" sw0p4 (part of br0) and sw1p4 (part of br1) are
the gateway ports between one bridge and another. This is hard to
manage from a user's perspective, who wants to have a unified view of
the switching fabric and the ability to transparently add ports to the
same bridge. VLANs would also need to be explicitly managed by the
user on these gateway ports.
So it seems that the only reasonable thing to do is to make DSA prefer
CPU ports that are local to the switch. Meaning that by default, the
user and DSA ports of switch 0 will get assigned to the CPU port from
switch 0 (sw0p1) and the user and DSA ports of switch 1 will get
assigned to the CPU port from switch 1.
The way this solves the problem is that sw1p4 is no longer an upstream
port as far as switch 1 is concerned (it no longer views sw0p1 as its
dedicated CPU port).
So here we are, the first multi-CPU port that DSA supports is also
perhaps the most uneventful one: the individual switches don't support
multiple CPUs, however the DSA switch tree as a whole does have multiple
CPU ports. No user space assignment of user ports to CPU ports is
desirable, necessary, or possible.
Ports that do not have a local CPU port (say there was an extra switch
hanging off of sw0p0) default to the standard implementation of getting
assigned to the first CPU port of the DSA switch tree. Is that good
enough? Probably not (if the downstream switch was hanging off of switch
1, we would most certainly prefer its CPU port to be sw1p1), but in
order to support that use case too, we would need to traverse the
dst->rtable in search of an optimum dedicated CPU port, one that has the
smallest number of hops between dp->ds and dp->cpu_dp->ds. At the
moment, the DSA routing table structure does not keep the number of hops
between dl->dp and dl->link_dp, and while it is probably deducible,
there is zero justification to write that code now. Let's hope DSA will
never have to support that use case.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
There is nothing specific to having a default CPU port to what
dsa_tree_teardown_default_cpu() does. Even with multiple CPU ports,
it would do the same thing: iterate through the ports of this switch
tree and reset the ->cpu_dp pointer to NULL. So rename it accordingly.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Dan Carpenter's smatch tests report that the "vid" variable, populated
by sja1105_vlan_rcv when an skb is received by the tagger that has a
VLAN ID which cannot be decoded by tag_8021q, may be uninitialized when
used here:
if (source_port == -1 || switch_id == -1)
skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid);
The sja1105 driver, by construction, sets up the switch in a way that
all data plane packets sent towards the CPU port are VLAN-tagged. So it
is practically impossible, in a functional system, for a packet to be
processed by sja1110_rcv() which is not a control packet and does not
have a VLAN header either.
However, it would be nice if the sja1105 tagging driver could
consistently do something valid, for example fail, even if presented with
packets that do not hold valid sja1105 tags. Currently it is a bit hard
to argue that it does that, given the fact that a data plane packet with
no VLAN tag will trigger a call to dsa_find_designated_bridge_port_by_vid
with a vid argument that is an uninitialized stack variable.
To fix this, we can initialize the u16 vid variable with 0, a value that
can never be a bridge VLAN, so dsa_find_designated_bridge_port_by_vid
will always return a NULL skb->dev.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20210802195137.303625-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
No tagging driver uses this.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
DSA has gained the recent ability to deal gracefully with upper
interfaces it cannot offload, such as the bridge, bonding or team
drivers. When such uppers exist, the ports are still in standalone mode
as far as the hardware is concerned.
But when we deliver packets to the software bridge in order for that to
do the forwarding, there is an unpleasant surprise in that the bridge
will refuse to forward them. This is because we unconditionally set
skb->offload_fwd_mark = true, meaning that the bridge thinks the frames
were already forwarded in hardware by us.
Since dp->bridge_dev is populated only when there is hardware offload
for it, but not in the software fallback case, let's introduce a new
helper that can be called from the tagger data path which sets the
skb->offload_fwd_mark accordingly to zero when there is no hardware
offload for bridging. This lets the bridge forward packets back to other
interfaces of our switch, if needed.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
imprecise port
On RX, a control packet with SJA1110 will have:
- an in-band control extension (DSA tag) composed of a header and an
optional trailer (if it is a timestamp frame). We can (and do) deduce
the source port and switch id from this.
- a VLAN header, which can either be the tag_8021q RX VLAN (pvid) or the
bridge VLAN. The sja1105_vlan_rcv() function attempts to deduce the
source port and switch id a second time from this.
The basic idea is that even though we don't need the source port
information from the tag_8021q header if it's a control packet, we do
need to strip that header before we pass it on to the network stack.
The problem is that we call sja1105_vlan_rcv for ports under VLAN-aware
bridges, and that function tells us it couldn't identify a tag_8021q
header, so we need to perform imprecise RX by VID. Well, we don't,
because we already know the source port and switch ID.
This patch drops the return value from sja1105_vlan_rcv and we just look
at the source_port and switch_id values from sja1105_rcv and sja1110_rcv
which were initialized to -1. If they are still -1 it means we need to
perform imprecise RX.
Fixes: 884be12f8566 ("net: dsa: sja1105: add support for imprecise RX")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Most users of ndo_do_ioctl are ethernet drivers that implement
the MII commands SIOCGMIIPHY/SIOCGMIIREG/SIOCSMIIREG, or hardware
timestamping with SIOCSHWTSTAMP/SIOCGHWTSTAMP.
Separate these from the few drivers that use ndo_do_ioctl to
implement SIOCBOND, SIOCBR and SIOCWANDEV commands.
This is a purely cosmetic change intended to help readers find
their way through the implementation.
Cc: Doug Ledford <dledford@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Vladimir Oltean <olteanv@gmail.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
port from"
This reverts commit cc1939e4b3aaf534fb2f3706820012036825731c.
Currently 2 classes of DSA drivers are able to send/receive packets
directly through the DSA master:
- drivers with DSA_TAG_PROTO_NONE
- sja1105
Now that sja1105 has gained the ability to perform traffic termination
even under the tricky case (VLAN-aware bridge), and that is much more
functional (we can perform VLAN-aware bridging with foreign interfaces),
there is no reason to keep this code in the receive path of the network
core. So delete it.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The main desire for having this feature in sja1105 is to support network
stack termination for traffic coming from a VLAN-aware bridge.
For sja1105, offloading the bridge data plane means sending packets
as-is, with the proper VLAN tag, to the chip. The chip will look up its
FDB and forward them to the correct destination port.
But we support bridge data plane offload even for VLAN-unaware bridges,
and the implementation there is different. In fact, VLAN-unaware
bridging is governed by tag_8021q, so it makes sense to have the
.bridge_fwd_offload_add() implementation fully within tag_8021q.
The key difference is that we only support 1 VLAN-aware bridge, but we
support multiple VLAN-unaware bridges. So we need to make sure that the
forwarding domain is not crossed by packets injected from the stack.
For this, we introduce the concept of a tag_8021q TX VLAN for bridge
forwarding offload. As opposed to the regular TX VLANs which contain
only 2 ports (the user port and the CPU port), a bridge data plane TX
VLAN is "multicast" (or "imprecise"): it contains all the ports that are
part of a certain bridge, and the hardware will select where the packet
goes within this "imprecise" forwarding domain.
Each VLAN-unaware bridge has its own "imprecise" TX VLAN, so we make use
of the unique "bridge_num" provided by DSA for the data plane offload.
We use the same 3 bits from the tag_8021q VLAN ID format to encode this
bridge number.
Note that these 3 bit positions have been used before for sub-VLANs in
best-effort VLAN filtering mode. The difference is that for best-effort,
the sub-VLANs were only valid on RX (and it was documented that the
sub-VLAN field needed to be transmitted as zero). Whereas for the bridge
data plane offload, these 3 bits are only valid on TX.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
This is already common knowledge by now, but the sja1105 does not have
hardware support for DSA tagging for data plane packets, and tag_8021q
sets up a unique pvid per port, transmitted as VLAN-tagged towards the
CPU, for the source port to be decoded nonetheless.
When the port is part of a VLAN-aware bridge, the pvid committed to
hardware is taken from the bridge and not from tag_8021q, so we need to
work with that the best we can.
Configure the switches to send all packets to the CPU as VLAN-tagged
(even ones that were originally untagged on the wire) and make use of
dsa_untag_bridge_pvid() to get rid of it before we send those packets up
the network stack.
With the classified VLAN used by hardware known to the tagger, we first
peek at the VID in an attempt to figure out if the packet was received
from a VLAN-unaware port (standalone or under a VLAN-unaware bridge),
case in which we can continue to call dsa_8021q_rcv(). If that is not
the case, the packet probably came from a VLAN-aware bridge. So we call
the DSA helper that finds for us a "designated bridge port" - one that
is a member of the VLAN ID from the packet, and is in the proper STP
state - basically these are all checks performed by br_handle_frame() in
the software RX data path.
The bridge will accept the packet as valid even if the source port was
maybe wrong. So it will maybe learn the MAC SA of the packet on the
wrong port, and its software FDB will be out of sync with the hardware
FDB. So replies towards this same MAC DA will not work, because the
bridge will send towards a different netdev.
This is where the bridge data plane offload ("imprecise TX") added by
the next patch comes in handy. The software FDB is wrong, true, but the
hardware FDB isn't, and by offloading the bridge forwarding plane we
have a chance to right a wrong, and have the hardware look up the FDB
for us for the reply packet. So it all cancels out.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Allow the DSA tagger to generate FORWARD frames for offloaded skbs
sent from a bridge that we offload, allowing the switch to handle any
frame replication that may be required. This also means that source
address learning takes place on packets sent from the CPU, meaning
that return traffic no longer needs to be flooded as unknown unicast.
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
For a DSA switch, to offload the forwarding process of a bridge device
means to send the packets coming from the software bridge as data plane
packets. This is contrary to everything that DSA has done so far,
because the current taggers only know to send control packets (ones that
target a specific destination port), whereas data plane packets are
supposed to be forwarded according to the FDB lookup, much like packets
ingressing on any regular ingress port. If the FDB lookup process
returns multiple destination ports (flooding, multicast), then
replication is also handled by the switch hardware - the bridge only
sends a single packet and avoids the skb_clone().
DSA keeps for each bridge port a zero-based index (the number of the
bridge). Multiple ports performing TX forwarding offload to the same
bridge have the same dp->bridge_num value, and ports not offloading the
TX data plane of a bridge have dp->bridge_num = -1.
The tagger can check if the packet that is being transmitted on has
skb->offload_fwd_mark = true or not. If it does, it can be sure that the
packet belongs to the data plane of a bridge, further information about
which can be obtained based on dp->bridge_dev and dp->bridge_num.
It can then compose a DSA tag for injecting a data plane packet into
that bridge number.
For the switch driver side, we offer two new dsa_switch_ops methods,
called .port_bridge_fwd_offload_{add,del}, which are modeled after
.port_bridge_{join,leave}.
These methods are provided in case the driver needs to configure the
hardware to treat packets coming from that bridge software interface as
data plane packets. The switchdev <-> bridge interaction happens during
the netdev_master_upper_dev_link() call, so to switch drivers, the
effect is that the .port_bridge_fwd_offload_add() method is called
immediately after .port_bridge_join().
If the bridge number exceeds the number of bridges for which the switch
driver can offload the TX data plane (and this includes the case where
the driver can offload none), DSA falls back to simply returning
tx_fwd_offload = false in the switchdev_bridge_port_offload() call.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
In preparation of supporting data plane forwarding on behalf of a
software bridge, some drivers might need to view bridges as virtual
switches behind the CPU port in a cross-chip topology.
Give them some help and let them know how many physical switches there
are in the tree, so that they can count the virtual switches starting
from that number on.
Note that the first dsa_switch_ops method where this information is
reliably available is .setup(). This is because of how DSA works:
in a tree with 3 switches, each calling dsa_register_switch(), the first
2 will advance until dsa_tree_setup() -> dsa_tree_setup_routing_table()
and exit with error code 0 because the topology is not complete. Since
probing is parallel at this point, one switch does not know about the
existence of the other. Then the third switch comes, and for it,
dsa_tree_setup_routing_table() returns complete = true. This switch goes
ahead and calls dsa_tree_setup_switches() for everybody else, calling
their .setup() methods too. This acts as the synchronization point.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Allow switchdevs to forward frames from the CPU in accordance with the
bridge configuration in the same way as is done between bridge
ports. This means that the bridge will only send a single skb towards
one of the ports under the switchdev's control, and expects the driver
to deliver the packet to all eligible ports in its domain.
Primarily this improves the performance of multicast flows with
multiple subscribers, as it allows the hardware to perform the frame
replication.
The basic flow between the driver and the bridge is as follows:
- When joining a bridge port, the switchdev driver calls
switchdev_bridge_port_offload() with tx_fwd_offload = true.
- The bridge sends offloadable skbs to one of the ports under the
switchdev's control using skb->offload_fwd_mark = true.
- The switchdev driver checks the skb->offload_fwd_mark field and lets
its FDB lookup select the destination port mask for this packet.
v1->v2:
- convert br_input_skb_cb::fwd_hwdoms to a plain unsigned long
- introduce a static key "br_switchdev_fwd_offload_used" to minimize the
impact of the newly introduced feature on all the setups which don't
have hardware that can make use of it
- introduce a check for nbp->flags & BR_FWD_OFFLOAD to optimize cache
line access
- reorder nbp_switchdev_frame_mark_accel() and br_handle_vlan() in
__br_forward()
- do not strip VLAN on egress if forwarding offload on VLAN-aware bridge
is being used
- propagate errors from .ndo_dfwd_add_station() if not EOPNOTSUPP
v2->v3:
- replace the solution based on .ndo_dfwd_add_station with a solution
based on switchdev_bridge_port_offload
- rename BR_FWD_OFFLOAD to BR_TX_FWD_OFFLOAD
v3->v4: rebase
v4->v5:
- make sure the static key is decremented on bridge port unoffload
- more function and variable renaming and comments for them:
br_switchdev_fwd_offload_used to br_switchdev_tx_fwd_offload
br_switchdev_accels_skb to br_switchdev_frame_uses_tx_fwd_offload
nbp_switchdev_frame_mark_tx_fwd to nbp_switchdev_frame_mark_tx_fwd_to_hwdom
nbp_switchdev_frame_mark_accel to nbp_switchdev_frame_mark_tx_fwd_offload
fwd_accel to tx_fwd_offload
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Conflicts are simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
|
