10269a2ca2
301 Commits
| Author | SHA1 | Message | Date | |
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Vladimir Oltean
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fd292c189a |
net: dsa: tear down devlink port regions when tearing down the devlink port on error
Commit |
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Vladimir Oltean
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0650bf52b3 |
net: dsa: be compatible with masters which unregister on shutdown
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:
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Vladimir Oltean
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a57d8c217a |
net: dsa: flush switchdev workqueue before tearing down CPU/DSA ports
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:
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Vladimir Oltean
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58adf9dcb1 |
net: dsa: let drivers state that they need VLAN filtering while standalone
As explained in commit
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Vladimir Oltean
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f5e165e72b |
net: dsa: track unique bridge numbers across all DSA switch trees
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> |
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Vladimir Oltean
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5313a37b88 |
net: dsa: sja1105: rely on DSA core tracking of port learning state
Now that DSA keeps track of the port learning state, it becomes superfluous to keep an additional variable with this information in the sja1105 driver. Remove it. The DSA core's learning state is present in struct dsa_port *dp. To avoid the antipattern where we iterate through a DSA switch's ports and then call dsa_to_port to obtain the "dp" reference (which is bad because dsa_to_port iterates through the DSA switch tree once again), just iterate through the dst->ports and operate on those directly. The sja1105 had an extra use of priv->learn_ena on non-user ports. DSA does not touch the learning state of those ports - drivers are free to do what they wish on them. Mark that information with a comment in struct dsa_port and let sja1105 set dp->learning for cascade ports. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
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045c45d1f5 |
net: dsa: centralize fast ageing when address learning is turned off
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> |
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Vladimir Oltean
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c73c57081b |
net: dsa: don't disable multicast flooding to the CPU even without an IGMP querier
Commit |
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Vladimir Oltean
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29a097b774 |
net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv()
No tagging driver uses this. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Arnd Bergmann
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a76053707d |
dev_ioctl: split out ndo_eth_ioctl
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> |
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Vladimir Oltean
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edac6f6332 |
Revert "net: dsa: Allow drivers to filter packets they can decode source port from"
This reverts commit
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Vladimir Oltean
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123abc06e7 |
net: dsa: add support for bridge TX forwarding offload
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>
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Vladimir Oltean
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5b22d3669f |
net: dsa: track the number of switches in a tree
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> |
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Vladimir Oltean
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5da11eb407 |
net: dsa: make tag_8021q operations part of the core
Make tag_8021q a more central element of DSA and move the 2 driver specific operations outside of struct dsa_8021q_context (which is supposed to hold dynamic data and not really constant function pointers). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
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d7b1fd520d |
net: dsa: let the core manage the tag_8021q context
The basic problem description is as follows:
Be there 3 switches in a daisy chain topology:
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sw0p0 sw0p1 sw0p2 sw0p3 sw0p4
[ user ] [ user ] [ user ] [ dsa ] [ cpu ]
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+---------+
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sw1p0 sw1p1 sw1p2 sw1p3 sw1p4
[ user ] [ user ] [ user ] [ dsa ] [ dsa ]
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+---------+
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sw2p0 sw2p1 sw2p2 sw2p3 sw2p4
[ user ] [ user ] [ user ] [ user ] [ dsa ]
The CPU will not be able to ping through the user ports of the
bottom-most switch (like for example sw2p0), simply because tag_8021q
was not coded up for this scenario - it has always assumed DSA switch
trees with a single switch.
To add support for the topology above, we must admit that the RX VLAN of
sw2p0 must be added on some ports of switches 0 and 1 as well. This is
in fact a textbook example of thing that can use the cross-chip notifier
framework that DSA has set up in switch.c.
There is only one problem: core DSA (switch.c) is not able right now to
make the connection between a struct dsa_switch *ds and a struct
dsa_8021q_context *ctx. Right now, it is drivers who call into
tag_8021q.c and always provide a struct dsa_8021q_context *ctx pointer,
and tag_8021q.c calls them back with the .tag_8021q_vlan_{add,del}
methods.
But with cross-chip notifiers, it is possible for tag_8021q to call
drivers without drivers having ever asked for anything. A good example
is right above: when sw2p0 wants to set itself up for tag_8021q,
the .tag_8021q_vlan_add method needs to be called for switches 1 and 0,
so that they transport sw2p0's VLANs towards the CPU without dropping
them.
So instead of letting drivers manage the tag_8021q context, add a
tag_8021q_ctx pointer inside of struct dsa_switch, which will be
populated when dsa_tag_8021q_register() returns success.
The patch is fairly long-winded because we are partly reverting commit
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Vladimir Oltean
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3f6e32f92a |
net: dsa: reference count the FDB addresses at the cross-chip notifier level
The same concerns expressed for host MDB entries are valid for host FDBs just as well: - in the case of multiple bridges spanning the same switch chip, deleting a host FDB entry that belongs to one bridge will result in breakage to the other bridge - not deleting FDB entries across DSA links means that the switch's hardware tables will eventually run out, given enough wear&tear So do the same thing and introduce reference counting for CPU ports and DSA links using the same data structures as we have for MDB entries. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
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161ca59d39 |
net: dsa: reference count the MDB entries at the cross-chip notifier level
Ever since the cross-chip notifiers were introduced, the design was
meant to be simplistic and just get the job done without worrying too
much about dangling resources left behind.
For example, somebody installs an MDB entry on sw0p0 in this daisy chain
topology. It gets installed using ds->ops->port_mdb_add() on sw0p0,
sw1p4 and sw2p4.
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sw0p0 sw0p1 sw0p2 sw0p3 sw0p4
[ user ] [ user ] [ user ] [ dsa ] [ cpu ]
[ x ] [ ] [ ] [ ] [ ]
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+---------+
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sw1p0 sw1p1 sw1p2 sw1p3 sw1p4
[ user ] [ user ] [ user ] [ dsa ] [ dsa ]
[ ] [ ] [ ] [ ] [ x ]
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+---------+
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sw2p0 sw2p1 sw2p2 sw2p3 sw2p4
[ user ] [ user ] [ user ] [ user ] [ dsa ]
[ ] [ ] [ ] [ ] [ x ]
Then the same person deletes that MDB entry. The cross-chip notifier for
deletion only matches sw0p0:
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sw0p0 sw0p1 sw0p2 sw0p3 sw0p4
[ user ] [ user ] [ user ] [ dsa ] [ cpu ]
[ x ] [ ] [ ] [ ] [ ]
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+---------+
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sw1p0 sw1p1 sw1p2 sw1p3 sw1p4
[ user ] [ user ] [ user ] [ dsa ] [ dsa ]
[ ] [ ] [ ] [ ] [ ]
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+---------+
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sw2p0 sw2p1 sw2p2 sw2p3 sw2p4
[ user ] [ user ] [ user ] [ user ] [ dsa ]
[ ] [ ] [ ] [ ] [ ]
Why?
Because the DSA links are 'trunk' ports, if we just go ahead and delete
the MDB from sw1p4 and sw2p4 directly, we might delete those multicast
entries when they are still needed. Just consider the fact that somebody
does:
- add a multicast MAC address towards sw0p0 [ via the cross-chip
notifiers it gets installed on the DSA links too ]
- add the same multicast MAC address towards sw0p1 (another port of that
same switch)
- delete the same multicast MAC address from sw0p0.
At this point, if we deleted the MAC address from the DSA links, it
would be flooded, even though there is still an entry on switch 0 which
needs it not to.
So that is why deletions only match the targeted source port and nothing
on DSA links. Of course, dangling resources means that the hardware
tables will eventually run out given enough additions/removals, but hey,
at least it's simple.
But there is a bigger concern which needs to be addressed, and that is
our support for SWITCHDEV_OBJ_ID_HOST_MDB. DSA simply translates such an
object into a dsa_port_host_mdb_add() which ends up as ds->ops->port_mdb_add()
on the upstream port, and a similar thing happens on deletion:
dsa_port_host_mdb_del() will trigger ds->ops->port_mdb_del() on the
upstream port.
When there are 2 VLAN-unaware bridges spanning the same switch (which is
a use case DSA proudly supports), each bridge will install its own
SWITCHDEV_OBJ_ID_HOST_MDB entries. But upon deletion, DSA goes ahead and
emits a DSA_NOTIFIER_MDB_DEL for dp->cpu_dp, which is shared between the
user ports enslaved to br0 and the user ports enslaved to br1. Not good.
The host-trapped multicast addresses installed by br1 will be deleted
when any state changes in br0 (IGMP timers expire, or ports leave, etc).
To avoid this, we could of course go the route of the zero-sum game and
delete the DSA_NOTIFIER_MDB_DEL call for dp->cpu_dp. But the better
design is to just admit that on shared ports like DSA links and CPU
ports, we should be reference counting calls, even if this consumes some
dynamic memory which DSA has traditionally avoided. On the flip side,
the hardware tables of switches are limited in size, so it would be good
if the OS managed them properly instead of having them eventually
overflow.
To address the memory usage concern, we only apply the refcounting of
MDB entries on ports that are really shared (CPU ports and DSA links)
and not on user ports. In a typical single-switch setup, this means only
the CPU port (and the host MDB entries are not that many, really).
The name of the newly introduced data structures (dsa_mac_addr) is
chosen in such a way that will be reusable for host FDB entries (next
patch).
With this change, we can finally have the same matching logic for the
MDB additions and deletions, as well as for their host-trapped variants.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Vladimir Oltean
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63609c8fac |
net: dsa: introduce dsa_is_upstream_port and dsa_switch_is_upstream_of
In preparation for the new cross-chip notifiers for host addresses, let's introduce some more topology helpers which we are going to use to discern switches that are in our path towards the dedicated CPU port from switches that aren't. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
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a8986681cc |
net: dsa: export the dsa_port_is_{user,cpu,dsa} helpers
The difference between dsa_is_user_port and dsa_port_is_user is that the former needs to look up the list of ports of the DSA switch tree in order to find the struct dsa_port, while the latter directly receives it as an argument. dsa_is_user_port is already in widespread use and has its place, so there isn't any chance of converting all callers to a single form. But being able to do: dsa_port_is_user(dp) instead of dsa_is_user_port(dp->ds, dp->index) is much more efficient too, especially when the "dp" comes from an iterator over the DSA switch tree - this reduces the complexity from quadratic to linear. Move these helpers from dsa2.c to include/net/dsa.h so that others can use them too. 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> |
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Vladimir Oltean
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4913b8ebf8 |
net: dsa: add support for the SJA1110 native tagging protocol
The SJA1110 has improved a few things compared to SJA1105:
- To send a control packet from the host port with SJA1105, one needed
to program a one-shot "management route" over SPI. This is no longer
true with SJA1110, you can actually send "in-band control extensions"
in the packets sent by DSA, these are in fact DSA tags which contain
the destination port and switch ID.
- When receiving a control packet from the switch with SJA1105, the
source port and switch ID were written in bytes 3 and 4 of the
destination MAC address of the frame (which was a very poor shot at a
DSA header). If the control packet also had an RX timestamp, that
timestamp was sent in an actual follow-up packet, so there were
reordering concerns on multi-core/multi-queue DSA masters, where the
metadata frame with the RX timestamp might get processed before the
actual packet to which that timestamp belonged (there is no way to
pair a packet to its timestamp other than the order in which they were
received). On SJA1110, this is no longer true, control packets have
the source port, switch ID and timestamp all in the DSA tags.
- Timestamps from the switch were partial: to get a 64-bit timestamp as
required by PTP stacks, one would need to take the partial 24-bit or
32-bit timestamp from the packet, then read the current PTP time very
quickly, and then patch in the high bits of the current PTP time into
the captured partial timestamp, to reconstruct what the full 64-bit
timestamp must have been. That is awful because packet processing is
done in NAPI context, but reading the current PTP time is done over
SPI and therefore needs sleepable context.
But it also aggravated a few things:
- Not only is there a DSA header in SJA1110, but there is a DSA trailer
in fact, too. So DSA needs to be extended to support taggers which
have both a header and a trailer. Very unconventional - my understanding
is that the trailer exists because the timestamps couldn't be prepared
in time for putting them in the header area.
- Like SJA1105, not all packets sent to the CPU have the DSA tag added
to them, only control packets do:
* the ones which match the destination MAC filters/traps in
MAC_FLTRES1 and MAC_FLTRES0
* the ones which match FDB entries which have TRAP or TAKETS bits set
So we could in theory hack something up to request the switch to take
timestamps for all packets that reach the CPU, and those would be
DSA-tagged and contain the source port / switch ID by virtue of the
fact that there needs to be a timestamp trailer provided. BUT:
- The SJA1110 does not parse its own DSA tags in a way that is useful
for routing in cross-chip topologies, a la Marvell. And the sja1105
driver already supports cross-chip bridging from the SJA1105 days.
It does that by automatically setting up the DSA links as VLAN trunks
which contain all the necessary tag_8021q RX VLANs that must be
communicated between the switches that span the same bridge. So when
using tag_8021q on sja1105, it is possible to have 2 switches with
ports sw0p0, sw0p1, sw1p0, sw1p1, and 2 VLAN-unaware bridges br0 and
br1, and br0 can take sw0p0 and sw1p0, and br1 can take sw0p1 and
sw1p1, and forwarding will happen according to the expected rules of
the Linux bridge.
We like that, and we don't want that to go away, so as a matter of
fact, the SJA1110 tagger still needs to support tag_8021q.
So the sja1110 tagger is a hybrid between tag_8021q for data packets,
and the native hardware support for control packets.
On RX, packets have a 13-byte trailer if they contain an RX timestamp.
That trailer is padded in such a way that its byte 8 (the start of the
"residence time" field - not parsed by Linux because we don't care) is
aligned on a 16 byte boundary. So the padding has a variable length
between 0 and 15 bytes. The DSA header contains the offset of the
beginning of the padding relative to the beginning of the frame (and the
end of the padding is obviously the end of the packet minus 13 bytes,
the length of the trailer). So we discard it.
Packets which don't have a trailer contain the source port and switch ID
information in the header (they are "trap-to-host" packets). Packets
which have a trailer contain the source port and switch ID in the trailer.
On TX, the destination port mask and switch ID is always in the trailer,
so we always need to say in the header that a trailer is present.
The header needs a custom EtherType and this was chosen as 0xdadc, after
0xdada which is for Marvell and 0xdadb which is for VLANs in
VLAN-unaware mode on SJA1105 (and SJA1110 in fact too).
Because we use tag_8021q in concert with the native tagging protocol,
control packets will have 2 DSA tags.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
Vladimir Oltean
|
4e50025129 |
net: dsa: generalize overhead for taggers that use both headers and trailers
Some really really weird switches just couldn't decide whether to use a normal or a tail tagger, so they just did both. This creates problems for DSA, because we only have the concept of an 'overhead' which can be applied to the headroom or to the tailroom of the skb (like for example during the central TX reallocation procedure), depending on the value of bool tail_tag, but not to both. We need to generalize DSA to cater for these odd switches by transforming the 'overhead / tail_tag' pair into 'needed_headroom / needed_tailroom'. The DSA master's MTU is increased to account for both. The flow dissector code is modified such that it only calls the DSA adjustment callback if the tagger has a non-zero header length. Taggers are trivially modified to declare either needed_headroom or needed_tailroom, based on the tail_tag value that they currently declare. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Yangbo Lu
|
c4b364ce12 |
net: dsa: free skb->cb usage in core driver
Free skb->cb usage in core driver and let device drivers decide to use or not. The reason having a DSA_SKB_CB(skb)->clone was because dsa_skb_tx_timestamp() which may set the clone pointer was called before p->xmit() which would use the clone if any, and the device driver has no way to initialize the clone pointer. This patch just put memset(skb->cb, 0, sizeof(skb->cb)) at beginning of dsa_slave_xmit(). Some new features in the future, like one-step timestamp may need more bytes of skb->cb to use in dsa_skb_tx_timestamp(), and p->xmit(). Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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|
Yangbo Lu
|
5c5416f5d4 |
net: dsa: no longer clone skb in core driver
It was a waste to clone skb directly in dsa_skb_tx_timestamp(). For one-step timestamping, a clone was not needed. For any failure of port_txtstamp (this may usually happen), the skb clone had to be freed. So this patch moves skb cloning for tx timestamp out of dsa core, and let drivers clone skb in port_txtstamp if they really need. Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> Tested-by: Kurt Kanzenbach <kurt@linutronix.de> Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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|
Yangbo Lu
|
cf536ea3c7 |
net: dsa: no longer identify PTP packet in core driver
Move ptp_classify_raw out of dsa core driver for handling tx timestamp request. Let device drivers do this if they want. Not all drivers want to limit tx timestamping for only PTP packet. Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> Tested-by: Kurt Kanzenbach <kurt@linutronix.de> Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Tobias Waldekranz
|
deff710703 |
net: dsa: Allow default tag protocol to be overridden from DT
Some combinations of tag protocols and Ethernet controllers are incompatible, and it is hard for the driver to keep track of these. Therefore, allow the device tree author (typically the board vendor) to inform the driver of this fact by selecting an alternate protocol that is known to work. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Oleksij Rempel
|
a71acad90a |
net: dsa: enable selftest support for all switches by default
Most of generic selftest should be able to work with probably all ethernet controllers. The DSA switches are not exception, so enable it by default at least for DSA. This patch was tested with SJA1105 and AR9331. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Michael Walle
|
83216e3988 |
of: net: pass the dst buffer to of_get_mac_address()
of_get_mac_address() returns a "const void*" pointer to a MAC address.
Lately, support to fetch the MAC address by an NVMEM provider was added.
But this will only work with platform devices. It will not work with
PCI devices (e.g. of an integrated root complex) and esp. not with DSA
ports.
There is an of_* variant of the nvmem binding which works without
devices. The returned data of a nvmem_cell_read() has to be freed after
use. On the other hand the return of_get_mac_address() points to some
static data without a lifetime. The trick for now, was to allocate a
device resource managed buffer which is then returned. This will only
work if we have an actual device.
Change it, so that the caller of of_get_mac_address() has to supply a
buffer where the MAC address is written to. Unfortunately, this will
touch all drivers which use the of_get_mac_address().
Usually the code looks like:
const char *addr;
addr = of_get_mac_address(np);
if (!IS_ERR(addr))
ether_addr_copy(ndev->dev_addr, addr);
This can then be simply rewritten as:
of_get_mac_address(np, ndev->dev_addr);
Sometimes is_valid_ether_addr() is used to test the MAC address.
of_get_mac_address() already makes sure, it just returns a valid MAC
address. Thus we can just test its return code. But we have to be
careful if there are still other sources for the MAC address before the
of_get_mac_address(). In this case we have to keep the
is_valid_ether_addr() call.
The following coccinelle patch was used to convert common cases to the
new style. Afterwards, I've manually gone over the drivers and fixed the
return code variable: either used a new one or if one was already
available use that. Mansour Moufid, thanks for that coccinelle patch!
<spml>
@a@
identifier x;
expression y, z;
@@
- x = of_get_mac_address(y);
+ x = of_get_mac_address(y, z);
<...
- ether_addr_copy(z, x);
...>
@@
identifier a.x;
@@
- if (<+... x ...+>) {}
@@
identifier a.x;
@@
if (<+... x ...+>) {
...
}
- else {}
@@
identifier a.x;
expression e;
@@
- if (<+... x ...+>@e)
- {}
- else
+ if (!(e))
{...}
@@
expression x, y, z;
@@
- x = of_get_mac_address(y, z);
+ of_get_mac_address(y, z);
... when != x
</spml>
All drivers, except drivers/net/ethernet/aeroflex/greth.c, were
compile-time tested.
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
Tobias Waldekranz
|
cc76ce9e8d |
net: dsa: Add helper to resolve bridge port from DSA port
In order for a driver to be able to query a bridge for information
about itself, e.g. reading out port flags, it has to use a netdev that
is known to the bridge. In the simple case, that is just the netdev
representing the port, e.g. swp0 or swp1 in this example:
br0
/ \
swp0 swp1
But in the case of an offloaded lag, this will be the bond or team
interface, e.g. bond0 in this example:
br0
/
bond0
/ \
swp0 swp1
Add a helper that hides some of this complexity from the
drivers. Then, redefine dsa_port_offloads_bridge_port using the helper
to avoid double accounting of the set of possible offloaded uppers.
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
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Álvaro Fernández Rojas
|
964dbf186e |
net: dsa: tag_brcm: add support for legacy tags
Add support for legacy Broadcom tags, which are similar to DSA_TAG_PROTO_BRCM. These tags are used on BCM5325, BCM5365 and BCM63xx switches. Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Horatiu Vultur
|
c595c4330d |
net: dsa: add MRP support
Add support for offloading MRP in HW. Currently implement the switchdev calls 'SWITCHDEV_OBJ_ID_MRP', 'SWITCHDEV_OBJ_ID_RING_ROLE_MRP', to allow to create MRP instances and to set the role of these instances. Add DSA_NOTIFIER_MRP_ADD/DEL and DSA_NOTIFIER_MRP_ADD/DEL_RING_ROLE which calls to .port_mrp_add/del and .port_mrp_add/del_ring_role in the DSA driver for the switch. Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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|
Vladimir Oltean
|
89153ed6eb |
net: dsa: propagate extack to .port_vlan_filtering
Some drivers can't dynamically change the VLAN filtering option, or impose some restrictions, it would be nice to propagate this info through netlink instead of printing it to a kernel log that might never be read. Also netlink extack includes the module that emitted the message, which means that it's easier to figure out which ones are driver-generated errors as opposed to command misuse. 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> |
||
|
Vladimir Oltean
|
31046a5fd9 |
net: dsa: propagate extack to .port_vlan_add
Allow drivers to communicate their restrictions to user space directly, instead of printing to the kernel log. Where the conversion would have been lossy and things like VLAN ID could no longer be conveyed (due to the lack of support for printf format specifier in netlink extack), I chose to keep the messages in full form to the kernel log only, and leave it up to individual driver maintainers to move more messages to extack. 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> |
||
|
Vladimir Oltean
|
7c4bb540e9 |
net: dsa: tag_ocelot: create separate tagger for Seville
The ocelot tagger is a hot mess currently, it relies on memory initialized by the attached driver for basic frame transmission. This is against all that DSA tagging protocols stand for, which is that the transmission and reception of a DSA-tagged frame, the data path, should be independent from the switch control path, because the tag protocol is in principle hot-pluggable and reusable across switches (even if in practice it wasn't until very recently). But if another driver like dsa_loop wants to make use of tag_ocelot, it couldn't. This was done to have common code between Felix and Ocelot, which have one bit difference in the frame header format. Quoting from commit |
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|
Vladimir Oltean
|
a8b659e7ff |
net: dsa: act as passthrough for bridge port flags
There are multiple ways in which a PORT_BRIDGE_FLAGS attribute can be expressed by the bridge through switchdev, and not all of them can be emulated by DSA mid-layer API at the same time. One possible configuration is when the bridge offloads the port flags using a mask that has a single bit set - therefore only one feature should change. However, DSA currently groups together unicast and multicast flooding in the .port_egress_floods method, which limits our options when we try to add support for turning off broadcast flooding: do we extend .port_egress_floods with a third parameter which b53 and mv88e6xxx will ignore? But that means that the DSA layer, which currently implements the PRE_BRIDGE_FLAGS attribute all by itself, will see that .port_egress_floods is implemented, and will report that all 3 types of flooding are supported - not necessarily true. Another configuration is when the user specifies more than one flag at the same time, in the same netlink message. If we were to create one individual function per offloadable bridge port flag, we would limit the expressiveness of the switch driver of refusing certain combinations of flag values. For example, a switch may not have an explicit knob for flooding of unknown multicast, just for flooding in general. In that case, the only correct thing to do is to allow changes to BR_FLOOD and BR_MCAST_FLOOD in tandem, and never allow mismatched values. But having a separate .port_set_unicast_flood and .port_set_multicast_flood would not allow the driver to possibly reject that. Also, DSA doesn't consider it necessary to inform the driver that a SWITCHDEV_ATTR_ID_BRIDGE_MROUTER attribute was offloaded, because it just calls .port_egress_floods for the CPU port. When we'll add support for the plain SWITCHDEV_ATTR_ID_PORT_MROUTER, that will become a real problem because the flood settings will need to be held statefully in the DSA middle layer, otherwise changing the mrouter port attribute will impact the flooding attribute. And that's _assuming_ that the underlying hardware doesn't have anything else to do when a multicast router attaches to a port than flood unknown traffic to it. If it does, there will need to be a dedicated .port_set_mrouter anyway. So we need to let the DSA drivers see the exact form that the bridge passes this switchdev attribute in, otherwise we are standing in the way. Therefore we also need to use this form of language when communicating to the driver that it needs to configure its initial (before bridge join) and final (after bridge leave) port flags. The b53 and mv88e6xxx drivers are converted to the passthrough API and their implementation of .port_egress_floods is split into two: a function that configures unicast flooding and another for multicast. The mv88e6xxx implementation is quite hairy, and it turns out that the implementations of unknown unicast flooding are actually the same for 6185 and for 6352: behind the confusing names actually lie two individual bits: NO_UNKNOWN_MC -> FLOOD_UC = 0x4 = BIT(2) NO_UNKNOWN_UC -> FLOOD_MC = 0x8 = BIT(3) so there was no reason to entangle them in the first place. Whereas the 6185 writes to MV88E6185_PORT_CTL0_FORWARD_UNKNOWN of PORT_CTL0, which has the exact same bit index. I have left the implementations separate though, for the only reason that the names are different enough to confuse me, since I am not able to double-check with a user manual. The multicast flooding setting for 6185 is in a different register than for 6352 though. 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> |
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George McCollister
|
18596f504a |
net: dsa: add support for offloading HSR
Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion
tag removal, duplicate generation and forwarding on DSA switches.
Add DSA_NOTIFIER_HSR_JOIN and DSA_NOTIFIER_HSR_LEAVE which trigger calls
to .port_hsr_join and .port_hsr_leave in the DSA driver for the switch.
The DSA switch driver should then set netdev feature flags for the
HSR/PRP operation that it offloads.
NETIF_F_HW_HSR_TAG_INS
NETIF_F_HW_HSR_TAG_RM
NETIF_F_HW_HSR_FWD
NETIF_F_HW_HSR_DUP
Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
Vladimir Oltean
|
7c83a7c539 |
net: dsa: add a second tagger for Ocelot switches based on tag_8021q
There are use cases for which the existing tagger, based on the NPI (Node Processor Interface) functionality, is insufficient. Namely: - Frames injected through the NPI port bypass the frame analyzer, so no source address learning is performed, no TSN stream classification, etc. - Flow control is not functional over an NPI port (PAUSE frames are encapsulated in the same Extraction Frame Header as all other frames) - There can be at most one NPI port configured for an Ocelot switch. But in NXP LS1028A and T1040 there are two Ethernet CPU ports. The non-NPI port is currently either disabled, or operated as a plain user port (albeit an internally-facing one). Having the ability to configure the two CPU ports symmetrically could pave the way for e.g. creating a LAG between them, to increase bandwidth seamlessly for the system. So there is a desire to have an alternative to the NPI mode. This change keeps the default tagger for the Seville and Felix switches as "ocelot", but it can be changed via the following device attribute: echo ocelot-8021q > /sys/class/<dsa-master>/dsa/tagging Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|
Vladimir Oltean
|
53da0ebaad |
net: dsa: allow changing the tag protocol via the "tagging" device attribute
Currently DSA exposes the following sysfs:
$ cat /sys/class/net/eno2/dsa/tagging
ocelot
which is a read-only device attribute, introduced in the kernel as
commit
|
||
|
Vladimir Oltean
|
357f203bb3 |
net: dsa: keep a copy of the tagging protocol in the DSA switch tree
Cascading DSA switches can be done multiple ways. There is the brute force approach / tag stacking, where one upstream switch, located between leaf switches and the host Ethernet controller, will just happily transport the DSA header of those leaf switches as payload. For this kind of setups, DSA works without any special kind of treatment compared to a single switch - they just aren't aware of each other. Then there's the approach where the upstream switch understands the tags it transports from its leaves below, as it doesn't push a tag of its own, but it routes based on the source port & switch id information present in that tag (as opposed to DMAC & VID) and it strips the tag when egressing a front-facing port. Currently only Marvell implements the latter, and Marvell DSA trees contain only Marvell switches. So it is safe to say that DSA trees already have a single tag protocol shared by all switches, and in fact this is what makes the switches able to understand each other. This fact is also implied by the fact that currently, the tagging protocol is reported as part of a sysfs installed on the DSA master and not per port, so it must be the same for all the ports connected to that DSA master regardless of the switch that they belong to. It's time to make this official and enforce it (yes, this also means we won't have any "switch understands tag to some extent but is not able to speak it" hardware oddities that we'll support in the future). This is needed due to the imminent introduction of the dsa_switch_ops:: change_tag_protocol driver API. When that is introduced, we'll have to notify switches of the tagging protocol that they're configured to use. Currently the tag_ops structure pointer is held only for CPU ports. But there are switches which don't have CPU ports and nonetheless still need to be configured. These would be Marvell leaf switches whose upstream port is just a DSA link. How do we inform these of their tagging protocol setup/deletion? One answer to the above would be: iterate through the DSA switch tree's ports once, list the CPU ports, get their tag_ops, then iterate again now that we have it, and notify everybody of that tag_ops. But what to do if conflicts appear between one cpu_dp->tag_ops and another? There's no escaping the fact that conflict resolution needs to be done, so we can be upfront about it. Ease our work and just keep the master copy of the tag_ops inside the struct dsa_switch_tree. Reference counting is now moved to be per-tree too, instead of per-CPU port. There are many places in the data path that access master->dsa_ptr->tag_ops and we would introduce unnecessary performance penalty going through yet another indirection, so keep those right where they are. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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|
Vladimir Oltean
|
2a6ef76303 |
net: dsa: add ops for devlink-sb
Switches that care about QoS might have hardware support for reserving buffer pools for individual ports or traffic classes, and configuring their sizes and thresholds. Through devlink-sb (shared buffers), this is all configurable, as well as their occupancy being viewable. Add the plumbing in DSA for these operations. Individual drivers still need to call devlink_sb_register() with the shared buffers they want to expose. A helper was not created in DSA for this purpose (unlike, say, dsa_devlink_params_register), since in my opinion it does not bring any benefit over plainly calling devlink_sb_register() directly. 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: Jakub Kicinski <kuba@kernel.org> |
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|
George McCollister
|
54a52823a2 |
dsa: add support for Arrow XRS700x tag trailer
Add support for Arrow SpeedChips XRS700x single byte tag trailer. This is modeled on tag_trailer.c which works in a similar way. Signed-off-by: George McCollister <george.mccollister@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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|
Tobias Waldekranz
|
058102a6e9 |
net: dsa: Link aggregation support
Monitor the following events and notify the driver when: - A DSA port joins/leaves a LAG. - A LAG, made up of DSA ports, joins/leaves a bridge. - A DSA port in a LAG is enabled/disabled (enabled meaning "distributing" in 802.3ad LACP terms). When a LAG joins a bridge, the DSA subsystem will treat that as each individual port joining the bridge. The driver may look at the port's LAG device pointer to see if it is associated with any LAG, if that is required. This is analogue to how switchdev events are replicated out to all lower devices when reaching e.g. a LAG. Drivers can optionally request that DSA maintain a linear mapping from a LAG ID to the corresponding netdev by setting ds->num_lag_ids to the desired size. In the event that the hardware is not capable of offloading a particular LAG for any reason (the typical case being use of exotic modes like broadcast), DSA will take a hands-off approach, allowing the LAG to be formed as a pure software construct. This is reported back through the extended ACK, but is otherwise transparent to the user. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Tested-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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|
Oleksij Rempel
|
c2ec5f2ecf |
net: dsa: add optional stats64 support
Allow DSA drivers to export stats64 Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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|
Vladimir Oltean
|
1958d5815c |
net: dsa: remove the transactional logic from VLAN objects
It should be the driver's business to logically separate its VLAN offloading into a preparation and a commit phase, and some drivers don't need / can't do this. So remove the transactional shim from DSA and let drivers propagate errors directly from the .port_vlan_add callback. It would appear that the code has worse error handling now than it had before. DSA is the only in-kernel user of switchdev that offloads one switchdev object to more than one port: for every VLAN object offloaded to a user port, that VLAN is also offloaded to the CPU port. So the "prepare for user port -> check for errors -> prepare for CPU port -> check for errors -> commit for user port -> commit for CPU port" sequence appears to make more sense than the one we are using now: "offload to user port -> check for errors -> offload to CPU port -> check for errors", but it is really a compromise. In the new way, we can catch errors from the commit phase that we previously had to ignore. But we have our hands tied and cannot do any rollback now: if we add a VLAN on the CPU port and it fails, we can't do the rollback by simply deleting it from the user port, because the switchdev API is not so nice with us: it could have simply been there already, even with the same flags. So we don't even attempt to rollback anything on addition error, just leave whatever VLANs managed to get offloaded right where they are. This should not be a problem at all in practice. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Vladimir Oltean
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a52b2da778 |
net: dsa: remove the transactional logic from MDB entries
For many drivers, the .port_mdb_prepare callback was not a good opportunity to avoid any error condition, and they would suppress errors found during the actual commit phase. Where a logical separation between the prepare and the commit phase existed, the function that used to implement the .port_mdb_prepare callback still exists, but now it is called directly from .port_mdb_add, which was modified to return an int code. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek Reviewed-by: Linus Wallei <linus.walleij@linaro.org> # RTL8366 Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Vladimir Oltean
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bae33f2b5a |
net: switchdev: remove the transaction structure from port attributes
Since the introduction of the switchdev API, port attributes were transmitted to drivers for offloading using a two-step transactional model, with a prepare phase that was supposed to catch all errors, and a commit phase that was supposed to never fail. Some classes of failures can never be avoided, like hardware access, or memory allocation. In the latter case, merely attempting to move the memory allocation to the preparation phase makes it impossible to avoid memory leaks, since commit |
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Vladimir Oltean
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1dbb130281 |
net: dsa: remove the DSA specific notifiers
This effectively reverts commit |
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Vladimir Oltean
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a5e3c9ba92 |
net: dsa: export dsa_slave_dev_check
Using the NETDEV_CHANGEUPPER notifications, drivers can be aware when they are enslaved to e.g. a bridge by calling netif_is_bridge_master(). Export this helper from DSA to get the equivalent functionality of determining whether the upper interface of a CHANGEUPPER notifier is a DSA switch interface or not. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Vladimir Oltean
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f46b9b8ee8 |
net: dsa: move the Broadcom tag information in a separate header file
It is a bit strange to see something as specific as Broadcom SYSTEMPORT bits in the main DSA include file. Move these away into a separate header, and have the tagger and the SYSTEMPORT driver include them. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Vladimir Oltean
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d5f19486ce |
net: dsa: listen for SWITCHDEV_{FDB,DEL}_ADD_TO_DEVICE on foreign bridge neighbors
Some DSA switches (and not only) cannot learn source MAC addresses from
packets injected from the CPU. They only perform hardware address
learning from inbound traffic.
This can be problematic when we have a bridge spanning some DSA switch
ports and some non-DSA ports (which we'll call "foreign interfaces" from
DSA's perspective).
There are 2 classes of problems created by the lack of learning on
CPU-injected traffic:
- excessive flooding, due to the fact that DSA treats those addresses as
unknown
- the risk of stale routes, which can lead to temporary packet loss
To illustrate the second class, consider the following situation, which
is common in production equipment (wireless access points, where there
is a WLAN interface and an Ethernet switch, and these form a single
bridging domain).
AP 1:
+------------------------------------------------------------------------+
| br0 |
+------------------------------------------------------------------------+
+------------+ +------------+ +------------+ +------------+ +------------+
| swp0 | | swp1 | | swp2 | | swp3 | | wlan0 |
+------------+ +------------+ +------------+ +------------+ +------------+
| ^ ^
| | |
| | |
| Client A Client B
|
|
|
+------------+ +------------+ +------------+ +------------+ +------------+
| swp0 | | swp1 | | swp2 | | swp3 | | wlan0 |
+------------+ +------------+ +------------+ +------------+ +------------+
+------------------------------------------------------------------------+
| br0 |
+------------------------------------------------------------------------+
AP 2
- br0 of AP 1 will know that Clients A and B are reachable via wlan0
- the hardware fdb of a DSA switch driver today is not kept in sync with
the software entries on other bridge ports, so it will not know that
clients A and B are reachable via the CPU port UNLESS the hardware
switch itself performs SA learning from traffic injected from the CPU.
Nonetheless, a substantial number of switches don't.
- the hardware fdb of the DSA switch on AP 2 may autonomously learn that
Client A and B are reachable through swp0. Therefore, the software br0
of AP 2 also may or may not learn this. In the example we're
illustrating, some Ethernet traffic has been going on, and br0 from AP
2 has indeed learnt that it can reach Client B through swp0.
One of the wireless clients, say Client B, disconnects from AP 1 and
roams to AP 2. The topology now looks like this:
AP 1:
+------------------------------------------------------------------------+
| br0 |
+------------------------------------------------------------------------+
+------------+ +------------+ +------------+ +------------+ +------------+
| swp0 | | swp1 | | swp2 | | swp3 | | wlan0 |
+------------+ +------------+ +------------+ +------------+ +------------+
| ^
| |
| Client A
|
|
| Client B
| |
| v
+------------+ +------------+ +------------+ +------------+ +------------+
| swp0 | | swp1 | | swp2 | | swp3 | | wlan0 |
+------------+ +------------+ +------------+ +------------+ +------------+
+------------------------------------------------------------------------+
| br0 |
+------------------------------------------------------------------------+
AP 2
- br0 of AP 1 still knows that Client A is reachable via wlan0 (no change)
- br0 of AP 1 will (possibly) know that Client B has left wlan0. There
are cases where it might never find out though. Either way, DSA today
does not process that notification in any way.
- the hardware FDB of the DSA switch on AP 1 may learn autonomously that
Client B can be reached via swp0, if it receives any packet with
Client 1's source MAC address over Ethernet.
- the hardware FDB of the DSA switch on AP 2 still thinks that Client B
can be reached via swp0. It does not know that it has roamed to wlan0,
because it doesn't perform SA learning from the CPU port.
Now Client A contacts Client B.
AP 1 routes the packet fine towards swp0 and delivers it on the Ethernet
segment.
AP 2 sees a frame on swp0 and its fdb says that the destination is swp0.
Hairpinning is disabled => drop.
This problem comes from the fact that these switches have a 'blind spot'
for addresses coming from software bridging. The generic solution is not
to assume that hardware learning can be enabled somehow, but to listen
to more bridge learning events. It turns out that the bridge driver does
learn in software from all inbound frames, in __br_handle_local_finish.
A proper SWITCHDEV_FDB_ADD_TO_DEVICE notification is emitted for the
addresses serviced by the bridge on 'foreign' interfaces. The software
bridge also does the right thing on migration, by notifying that the old
entry is deleted, so that does not need to be special-cased in DSA. When
it is deleted, we just need to delete our static FDB entry towards the
CPU too, and wait.
The problem is that DSA currently only cares about SWITCHDEV_FDB_ADD_TO_DEVICE
events received on its own interfaces, such as static FDB entries.
Luckily we can change that, and DSA can listen to all switchdev FDB
add/del events in the system and figure out if those events were emitted
by a bridge that spans at least one of DSA's own ports. In case that is
true, DSA will also offload that address towards its own CPU port, in
the eventuality that there might be bridge clients attached to the DSA
switch who want to talk to the station connected to the foreign
interface.
In terms of implementation, we need to keep the fdb_info->added_by_user
check for the case where the switchdev event was targeted directly at a
DSA switch port. But we don't need to look at that flag for snooped
events. So the check is currently too late, we need to move it earlier.
This also simplifies the code a bit, since we avoid uselessly allocating
and freeing switchdev_work.
We could probably do some improvements in the future. For example,
multi-bridge support is rudimentary at the moment. If there are two
bridges spanning a DSA switch's ports, and both of them need to service
the same MAC address, then what will happen is that the migration of one
of those stations will trigger the deletion of the FDB entry from the
CPU port while it is still used by other bridge. That could be improved
with reference counting but is left for another time.
This behavior needs to be enabled at driver level by setting
ds->assisted_learning_on_cpu_port = true. This is because we don't want
to inflict a potential performance penalty (accesses through
MDIO/I2C/SPI are expensive) to hardware that really doesn't need it
because address learning on the CPU port works there.
Reported-by: DENG Qingfang <dqfext@gmail.com>
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: Jakub Kicinski <kuba@kernel.org>
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Vladimir Oltean
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e358bef7c3 |
net: dsa: Give drivers the chance to veto certain upper devices
Some switches rely on unique pvids to ensure port separation in standalone mode, because they don't have a port forwarding matrix configurable in hardware. So, setups like a group of 2 uppers with the same VLAN, swp0.100 and swp1.100, will cause traffic tagged with VLAN 100 to be autonomously forwarded between these switch ports, in spite of there being no bridge between swp0 and swp1. These drivers need to prevent this from happening. They need to have VLAN filtering enabled in standalone mode (so they'll drop frames tagged with unknown VLANs) and they can only accept an 8021q upper on a port as long as it isn't installed on any other port too. So give them the chance to veto bad user requests. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> [Kurt: Pass info instead of ptr] Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |