Граф коммитов

1127 Коммитов

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Vladimir Oltean 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>
2021-08-23 11:52:31 +01:00
Vladimir Oltean 994d2cbb08 net: dsa: tag_sja1105: be dsa_loop-safe
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>
2021-08-18 10:33:15 +01:00
Vladimir Oltean b2b8913341 net: dsa: tag_8021q: fix notifiers broadcast when they shouldn't, and vice versa
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: 724395f4dc ("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>
2021-08-16 11:14:18 +01:00
Jakub Kicinski f4083a752a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h
  9e26680733 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp")
  9e518f2580 ("bnxt_en: 1PPS functions to configure TSIO pins")
  099fdeda65 ("bnxt_en: Event handler for PPS events")

kernel/bpf/helpers.c
include/linux/bpf-cgroup.h
  a2baf4e8bb ("bpf: Fix potentially incorrect results with bpf_get_local_storage()")
  c7603cfa04 ("bpf: Add ambient BPF runtime context stored in current")

drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
  5957cc557d ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray")
  2d0b41a376 ("net/mlx5: Refcount mlx5_irq with integer")

MAINTAINERS
  7b637cd52f ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo")
  7d901a1e87 ("net: phy: add Maxlinear GPY115/21x/24x driver")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-13 06:41:22 -07:00
Vladimir Oltean 724395f4dc net: dsa: tag_8021q: don't broadcast during setup/teardown
Currently, on my board with multiple sja1105 switches in disjoint trees
described in commit f66a6a69f9 ("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>
2021-08-12 11:46:21 +01:00
Vladimir Oltean ab97462beb net: dsa: print more information when a cross-chip notifier fails
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>
2021-08-12 11:46:21 +01:00
Vladimir Oltean a72808b658 net: dsa: create a helper for locating EtherType DSA headers on TX
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>
2021-08-11 14:44:58 +01:00
Vladimir Oltean 5d928ff486 net: dsa: create a helper for locating EtherType DSA headers on RX
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>
2021-08-11 14:44:58 +01:00
Vladimir Oltean 6bef794da6 net: dsa: create a helper which allocates space for EtherType DSA headers
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>
2021-08-11 14:44:58 +01:00
Vladimir Oltean f1dacd7aea net: dsa: create a helper that strips EtherType DSA headers on RX
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>
2021-08-11 14:44:58 +01:00
Vladimir Oltean c35b57ceff net: switchdev: zero-initialize struct switchdev_notifier_fdb_info emitted 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: 2c4eca3ef7 ("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>
2021-08-10 13:22:57 -07:00
Leon Romanovsky 919d13a7e4 devlink: Set device as early as possible
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>
2021-08-09 10:21:40 +01:00
Vladimir Oltean bee7c577e6 net: dsa: avoid fast ageing twice when port leaves a bridge
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>
2021-08-09 09:57:53 +01:00
Vladimir Oltean a4ffe09fc2 net: dsa: still fast-age ports joining a bridge if they can't configure learning
Commit 39f3210154 ("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>
2021-08-09 09:57:53 +01:00
Vladimir Oltean 9264e4ad26 net: dsa: flush the dynamic FDB of the software bridge when fast ageing a port
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>
2021-08-08 20:56:51 +01:00
Vladimir Oltean 4eab90d973 net: dsa: don't fast age bridge ports with learning turned off
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>
2021-08-08 20:56:51 +01:00
Vladimir Oltean 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>
2021-08-08 20:56:51 +01:00
Vladimir Oltean 39f3210154 net: dsa: don't fast age standalone ports
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 5e38c15856 ("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>
2021-08-08 12:52:53 +01:00
Vladimir Oltean c73c57081b net: dsa: don't disable multicast flooding to the CPU even without an IGMP querier
Commit 08cc83cc7f ("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 a8b659e7ff ("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: a8b659e7ff ("net: dsa: act as passthrough for bridge port flags")
Fixes: 08cc83cc7f ("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>
2021-08-06 11:11:13 +01:00
Vladimir Oltean 7df4e74494 net: dsa: stop syncing the bridge mcast_router attribute at join time
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: 010e269f91 ("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>
2021-08-06 11:11:13 +01:00
Vladimir Oltean f8b17a0bd9 net: dsa: tag_sja1105: optionally build as module when switch driver is 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: 566b18c8b7 ("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>
2021-08-05 13:30:14 +01:00
Vladimir Oltean 2c0b03258b net: dsa: give preference to local CPU ports
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>
2021-08-05 11:05:48 +01:00
Vladimir Oltean 0e8eb9a16e net: dsa: rename teardown_default_cpu to teardown_cpu_ports
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>
2021-08-05 11:05:48 +01:00
Vladimir Oltean 421297efe6 net: dsa: tag_sja1105: consistently fail with arbitrary input
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>
2021-08-03 14:31:54 -07:00
Vladimir Oltean 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>
2021-08-02 15:13:15 +01:00
Vladimir Oltean bea7907837 net: dsa: don't set skb->offload_fwd_mark when not offloading the bridge
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>
2021-07-29 22:17:37 +01:00
Vladimir Oltean 04a1758348 net: dsa: tag_sja1105: fix control packets on SJA1110 being received on an 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: 884be12f85 ("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>
2021-07-29 15:35:01 +01:00
Arnd Bergmann 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>
2021-07-27 20:11:45 +01:00
Vladimir Oltean edac6f6332 Revert "net: dsa: Allow drivers to filter packets they can decode source port from"
This reverts commit cc1939e4b3.

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>
2021-07-26 22:35:22 +01:00
Vladimir Oltean b6ad86e6ad net: dsa: sja1105: add bridge TX data plane offload based on tag_8021q
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>
2021-07-26 22:35:22 +01:00
Vladimir Oltean 884be12f85 net: dsa: sja1105: add support for imprecise RX
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>
2021-07-26 22:35:22 +01:00
Tobias Waldekranz d82f8ab0d8 net: dsa: tag_dsa: offload the bridge forwarding process
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>
2021-07-23 16:32:37 +01:00
Vladimir Oltean 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>
2021-07-23 16:32:37 +01:00
Vladimir Oltean 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>
2021-07-23 16:32:37 +01:00
Tobias Waldekranz 472111920f net: bridge: switchdev: allow the TX data plane forwarding to be offloaded
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>
2021-07-23 16:32:37 +01:00
David S. Miller 5af84df962 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts are simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23 16:13:06 +01:00
Vladimir Oltean 4e51bf44a0 net: bridge: move the switchdev object replay helpers to "push" mode
Starting with commit 4f2673b3a2 ("net: bridge: add helper to replay
port and host-joined mdb entries"), DSA has introduced some bridge
helpers that replay switchdev events (FDB/MDB/VLAN additions and
deletions) that can be lost by the switchdev drivers in a variety of
circumstances:

- an IP multicast group was host-joined on the bridge itself before any
  switchdev port joined the bridge, leading to the host MDB entries
  missing in the hardware database.
- during the bridge creation process, the MAC address of the bridge was
  added to the FDB as an entry pointing towards the bridge device
  itself, but with no switchdev ports being part of the bridge yet, this
  local FDB entry would remain unknown to the switchdev hardware
  database.
- a VLAN/FDB/MDB was added to a bridge port that is a LAG interface,
  before any switchdev port joined that LAG, leading to the hardware
  database missing those entries.
- a switchdev port left a LAG that is a bridge port, while the LAG
  remained part of the bridge, and all FDB/MDB/VLAN entries remained
  installed in the hardware database of the switchdev port.

Also, since commit 0d2cfbd41c ("net: bridge: ignore switchdev events
for LAG ports which didn't request replay"), DSA introduced a method,
based on a const void *ctx, to ensure that two switchdev ports under the
same LAG that is a bridge port do not see the same MDB/VLAN entry being
replayed twice by the bridge, once for every bridge port that joins the
LAG.

With so many ordering corner cases being possible, it seems unreasonable
to expect a switchdev driver writer to get it right from the first try.
Therefore, now that DSA has experimented with the bridge replay helpers
for a little bit, we can move the code to the bridge driver where it is
more readily available to all switchdev drivers.

To convert the switchdev object replay helpers from "pull mode" (where
the driver asks for them) to a "push mode" (where the bridge offers them
automatically), the biggest problem is that the bridge needs to be aware
when a switchdev port joins and leaves, even when the switchdev is only
indirectly a bridge port (for example when the bridge port is a LAG
upper of the switchdev).

Luckily, we already have a hook for that, in the form of the newly
introduced switchdev_bridge_port_offload() and
switchdev_bridge_port_unoffload() calls. These offer a natural place for
hooking the object addition and deletion replays.

Extend the above 2 functions with:
- pointers to the switchdev atomic notifier (for FDB replays) and the
  blocking notifier (for MDB and VLAN replays).
- the "const void *ctx" argument required for drivers to be able to
  disambiguate between which port is targeted, when multiple ports are
  lowers of the same LAG that is a bridge port. Most of the drivers pass
  NULL to this argument, except the ones that support LAG offload and have
  the proper context check already in place in the switchdev blocking
  notifier handler.

Also unexport the replay helpers, since nobody except the bridge calls
them directly now.

Note that:
(a) we abuse the terminology slightly, because FDB entries are not
    "switchdev objects", but we count them as objects nonetheless.
    With no direct way to prove it, I think they are not modeled as
    switchdev objects because those can only be installed by the bridge
    to the hardware (as opposed to FDB entries which can be propagated
    in the other direction too). This is merely an abuse of terms, FDB
    entries are replayed too, despite not being objects.
(b) the bridge does not attempt to sync port attributes to newly joined
    ports, just the countable stuff (the objects). The reason for this
    is simple: no universal and symmetric way to sync and unsync them is
    known. For example, VLAN filtering: what to do on unsync, disable or
    leave it enabled? Similarly, STP state, ageing timer, etc etc. What
    a switchdev port does when it becomes standalone again is not really
    up to the bridge's competence, and the driver should deal with it.
    On the other hand, replaying deletions of switchdev objects can be
    seen a matter of cleanup and therefore be treated by the bridge,
    hence this patch.

We make the replay helpers opt-in for drivers, because they might not
bring immediate benefits for them:

- nbp_vlan_init() is called _after_ netdev_master_upper_dev_link(),
  so br_vlan_replay() should not do anything for the new drivers on
  which we call it. The existing drivers where there was even a slight
  possibility for there to exist a VLAN on a bridge port before they
  join it are already guarded against this: mlxsw and prestera deny
  joining LAG interfaces that are members of a bridge.

- br_fdb_replay() should now notify of local FDB entries, but I patched
  all drivers except DSA to ignore these new entries in commit
  2c4eca3ef7 ("net: bridge: switchdev: include local flag in FDB
  notifications"). Driver authors can lift this restriction as they
  wish, and when they do, they can also opt into the FDB replay
  functionality.

- br_mdb_replay() should fix a real issue which is described in commit
  4f2673b3a2 ("net: bridge: add helper to replay port and host-joined
  mdb entries"). However most drivers do not offload the
  SWITCHDEV_OBJ_ID_HOST_MDB to see this issue: only cpsw and am65_cpsw
  offload this switchdev object, and I don't completely understand the
  way in which they offload this switchdev object anyway. So I'll leave
  it up to these drivers' respective maintainers to opt into
  br_mdb_replay().

So most of the drivers pass NULL notifier blocks for the replay helpers,
except:
- dpaa2-switch which was already acked/regression-tested with the
  helpers enabled (and there isn't much of a downside in having them)
- ocelot which already had replay logic in "pull" mode
- DSA which already had replay logic in "pull" mode

An important observation is that the drivers which don't currently
request bridge event replays don't even have the
switchdev_bridge_port_{offload,unoffload} calls placed in proper places
right now. This was done to avoid unnecessary rework for drivers which
might never even add support for this. For driver writers who wish to
add replay support, this can be used as a tentative placement guide:
https://patchwork.kernel.org/project/netdevbpf/patch/20210720134655.892334-11-vladimir.oltean@nxp.com/

Cc: Vadym Kochan <vkochan@marvell.com>
Cc: Taras Chornyi <tchornyi@marvell.com>
Cc: Ioana Ciornei <ioana.ciornei@nxp.com>
Cc: Lars Povlsen <lars.povlsen@microchip.com>
Cc: Steen Hegelund <Steen.Hegelund@microchip.com>
Cc: UNGLinuxDriver@microchip.com
Cc: Claudiu Manoil <claudiu.manoil@nxp.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22 00:26:23 -07:00
Vladimir Oltean 2f5dc00f7a net: bridge: switchdev: let drivers inform which bridge ports are offloaded
On reception of an skb, the bridge checks if it was marked as 'already
forwarded in hardware' (checks if skb->offload_fwd_mark == 1), and if it
is, it assigns the source hardware domain of that skb based on the
hardware domain of the ingress port. Then during forwarding, it enforces
that the egress port must have a different hardware domain than the
ingress one (this is done in nbp_switchdev_allowed_egress).

Non-switchdev drivers don't report any physical switch id (neither
through devlink nor .ndo_get_port_parent_id), therefore the bridge
assigns them a hardware domain of 0, and packets coming from them will
always have skb->offload_fwd_mark = 0. So there aren't any restrictions.

Problems appear due to the fact that DSA would like to perform software
fallback for bonding and team interfaces that the physical switch cannot
offload.

       +-- br0 ---+
      / /   |      \
     / /    |       \
    /  |    |      bond0
   /   |    |     /    \
 swp0 swp1 swp2 swp3 swp4

There, it is desirable that the presence of swp3 and swp4 under a
non-offloaded LAG does not preclude us from doing hardware bridging
beteen swp0, swp1 and swp2. The bandwidth of the CPU is often times high
enough that software bridging between {swp0,swp1,swp2} and bond0 is not
impractical.

But this creates an impossible paradox given the current way in which
port hardware domains are assigned. When the driver receives a packet
from swp0 (say, due to flooding), it must set skb->offload_fwd_mark to
something.

- If we set it to 0, then the bridge will forward it towards swp1, swp2
  and bond0. But the switch has already forwarded it towards swp1 and
  swp2 (not to bond0, remember, that isn't offloaded, so as far as the
  switch is concerned, ports swp3 and swp4 are not looking up the FDB,
  and the entire bond0 is a destination that is strictly behind the
  CPU). But we don't want duplicated traffic towards swp1 and swp2, so
  it's not ok to set skb->offload_fwd_mark = 0.

- If we set it to 1, then the bridge will not forward the skb towards
  the ports with the same switchdev mark, i.e. not to swp1, swp2 and
  bond0. Towards swp1 and swp2 that's ok, but towards bond0? It should
  have forwarded the skb there.

So the real issue is that bond0 will be assigned the same hardware
domain as {swp0,swp1,swp2}, because the function that assigns hardware
domains to bridge ports, nbp_switchdev_add(), recurses through bond0's
lower interfaces until it finds something that implements devlink (calls
dev_get_port_parent_id with bool recurse = true). This is a problem
because the fact that bond0 can be offloaded by swp3 and swp4 in our
example is merely an assumption.

A solution is to give the bridge explicit hints as to what hardware
domain it should use for each port.

Currently, the bridging offload is very 'silent': a driver registers a
netdevice notifier, which is put on the netns's notifier chain, and
which sniffs around for NETDEV_CHANGEUPPER events where the upper is a
bridge, and the lower is an interface it knows about (one registered by
this driver, normally). Then, from within that notifier, it does a bunch
of stuff behind the bridge's back, without the bridge necessarily
knowing that there's somebody offloading that port. It looks like this:

     ip link set swp0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v
        call_netdevice_notifiers
                  |
                  v
       dsa_slave_netdevice_event
                  |
                  v
        oh, hey! it's for me!
                  |
                  v
           .port_bridge_join

What we do to solve the conundrum is to be less silent, and change the
switchdev drivers to present themselves to the bridge. Something like this:

     ip link set swp0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v                    bridge: Aye! I'll use this
        call_netdevice_notifiers           ^  ppid as the
                  |                        |  hardware domain for
                  v                        |  this port, and zero
       dsa_slave_netdevice_event           |  if I got nothing.
                  |                        |
                  v                        |
        oh, hey! it's for me!              |
                  |                        |
                  v                        |
           .port_bridge_join               |
                  |                        |
                  +------------------------+
             switchdev_bridge_port_offload(swp0, swp0)

Then stacked interfaces (like bond0 on top of swp3/swp4) would be
treated differently in DSA, depending on whether we can or cannot
offload them.

The offload case:

    ip link set bond0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v                    bridge: Aye! I'll use this
        call_netdevice_notifiers           ^  ppid as the
                  |                        |  switchdev mark for
                  v                        |        bond0.
       dsa_slave_netdevice_event           | Coincidentally (or not),
                  |                        | bond0 and swp0, swp1, swp2
                  v                        | all have the same switchdev
        hmm, it's not quite for me,        | mark now, since the ASIC
         but my driver has already         | is able to forward towards
           called .port_lag_join           | all these ports in hw.
          for it, because I have           |
      a port with dp->lag_dev == bond0.    |
                  |                        |
                  v                        |
           .port_bridge_join               |
           for swp3 and swp4               |
                  |                        |
                  +------------------------+
            switchdev_bridge_port_offload(bond0, swp3)
            switchdev_bridge_port_offload(bond0, swp4)

And the non-offload case:

    ip link set bond0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v                    bridge waiting:
        call_netdevice_notifiers           ^  huh, switchdev_bridge_port_offload
                  |                        |  wasn't called, okay, I'll use a
                  v                        |  hwdom of zero for this one.
       dsa_slave_netdevice_event           :  Then packets received on swp0 will
                  |                        :  not be software-forwarded towards
                  v                        :  swp1, but they will towards bond0.
         it's not for me, but
       bond0 is an upper of swp3
      and swp4, but their dp->lag_dev
       is NULL because they couldn't
            offload it.

Basically we can draw the conclusion that the lowers of a bridge port
can come and go, so depending on the configuration of lowers for a
bridge port, it can dynamically toggle between offloaded and unoffloaded.
Therefore, we need an equivalent switchdev_bridge_port_unoffload too.

This patch changes the way any switchdev driver interacts with the
bridge. From now on, everybody needs to call switchdev_bridge_port_offload
and switchdev_bridge_port_unoffload, otherwise the bridge will treat the
port as non-offloaded and allow software flooding to other ports from
the same ASIC.

Note that these functions lay the ground for a more complex handshake
between switchdev drivers and the bridge in the future.

For drivers that will request a replay of the switchdev objects when
they offload and unoffload a bridge port (DSA, dpaa2-switch, ocelot), we
place the call to switchdev_bridge_port_unoffload() strategically inside
the NETDEV_PRECHANGEUPPER notifier's code path, and not inside
NETDEV_CHANGEUPPER. This is because the switchdev object replay helpers
need the netdev adjacency lists to be valid, and that is only true in
NETDEV_PRECHANGEUPPER.

Cc: Vadym Kochan <vkochan@marvell.com>
Cc: Taras Chornyi <tchornyi@marvell.com>
Cc: Ioana Ciornei <ioana.ciornei@nxp.com>
Cc: Lars Povlsen <lars.povlsen@microchip.com>
Cc: Steen Hegelund <Steen.Hegelund@microchip.com>
Cc: UNGLinuxDriver@microchip.com
Cc: Claudiu Manoil <claudiu.manoil@nxp.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch: regression
Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com> # ocelot-switch
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22 00:26:23 -07:00
Lino Sanfilippo 37120f23ac net: dsa: tag_ksz: dont let the hardware process the layer 4 checksum
If the checksum calculation is offloaded to the network device (e.g due to
NETIF_F_HW_CSUM inherited from the DSA master device), the calculated
layer 4 checksum is incorrect. This is since the DSA tag which is placed
after the layer 4 data is considered as being part of the daa and thus
errorneously included into the checksum calculation.
To avoid this, always calculate the layer 4 checksum in software.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21 23:14:49 -07:00
Lino Sanfilippo 21cf377a9c net: dsa: ensure linearized SKBs in case of tail taggers
The function skb_put() that is used by tail taggers to make room for the
DSA tag must only be called for linearized SKBS. However in case that the
slave device inherited features like NETIF_F_HW_SG or NETIF_F_FRAGLIST the
SKB passed to the slaves transmit function may not be linearized.
Avoid those SKBs by clearing the NETIF_F_HW_SG and NETIF_F_FRAGLIST flags
for tail taggers.
Furthermore since the tagging protocol can be changed at runtime move the
code for setting up the slaves features into dsa_slave_setup_tagger().

Suggested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21 23:14:49 -07:00
Vladimir Oltean b94dc99c0d net: dsa: use switchdev_handle_fdb_{add,del}_to_device
Using the new fan-out helper for FDB entries installed on the software
bridge, we can install host addresses with the proper refcount on the
CPU port, such that this case:

ip link set swp0 master br0
ip link set swp1 master br0
ip link set swp2 master br0
ip link set swp3 master br0
ip link set br0 address 00:01:02:03:04:05
ip link set swp3 nomaster

works properly and the br0 address remains installed as a host entry
with refcount 3 instead of getting deleted.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 07:04:27 -07:00
Vladimir Oltean c6451cda10 net: switchdev: introduce helper for checking dynamically learned FDB entries
It is a bit difficult to understand what DSA checks when it tries to
avoid installing dynamically learned addresses on foreign interfaces as
local host addresses, so create a generic switchdev helper that can be
reused and is generally more readable.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 07:04:27 -07:00
Vladimir Oltean c64b9c0504 net: dsa: tag_8021q: add proper cross-chip notifier support
The big problem which mandates cross-chip notifiers for tag_8021q is
this:

                                             |
    sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
 [  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
                                   |
                                   +---------+
                                             |
    sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
 [  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
                                   |
                                   +---------+
                                             |
    sw2p0     sw2p1     sw2p2     sw2p3     sw2p4
 [  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]

When the user runs:

ip link add br0 type bridge
ip link set sw0p0 master br0
ip link set sw2p0 master br0

It doesn't work.

This is because dsa_8021q_crosschip_bridge_join() assumes that "ds" and
"other_ds" are at most 1 hop away from each other, so it is sufficient
to add the RX VLAN of {ds, port} into {other_ds, other_port} and vice
versa and presto, the cross-chip link works. When there is another
switch in the middle, such as in this case switch 1 with its DSA links
sw1p3 and sw1p4, somebody needs to tell it about these VLANs too.

Which is exactly why the problem is quadratic: when a port joins a
bridge, for each port in the tree that's already in that same bridge we
notify a tag_8021q VLAN addition of that port's RX VLAN to the entire
tree. It is a very complicated web of VLANs.

It must be mentioned that currently we install tag_8021q VLANs on too
many ports (DSA links - to be precise, on all of them). For example,
when sw2p0 joins br0, and assuming sw1p0 was part of br0 too, we add the
RX VLAN of sw2p0 on the DSA links of switch 0 too, even though there
isn't any port of switch 0 that is a member of br0 (at least yet).
In theory we could notify only the switches which sit in between the
port joining the bridge and the port reacting to that bridge_join event.
But in practice that is impossible, because of the way 'link' properties
are described in the device tree. The DSA bindings require DT writers to
list out not only the real/physical DSA links, but in fact the entire
routing table, like for example switch 0 above will have:

	sw0p3: port@3 {
		link = <&sw1p4 &sw2p4>;
	};

This was done because:

/* TODO: ideally DSA ports would have a single dp->link_dp member,
 * and no dst->rtable nor this struct dsa_link would be needed,
 * but this would require some more complex tree walking,
 * so keep it stupid at the moment and list them all.
 */

but it is a perfect example of a situation where too much information is
actively detrimential, because we are now in the position where we
cannot distinguish a real DSA link from one that is put there to avoid
the 'complex tree walking'. And because DT is ABI, there is not much we
can change.

And because we do not know which DSA links are real and which ones
aren't, we can't really know if DSA switch A is in the data path between
switches B and C, in the general case.

So this is why tag_8021q RX VLANs are added on all DSA links, and
probably why it will never change.

On the other hand, at least the number of additions/deletions is well
balanced, and this means that once we implement reference counting at
the cross-chip notifier level a la fdb/mdb, there is absolutely zero
need for a struct dsa_8021q_crosschip_link, it's all self-managing.

In fact, with the tag_8021q notifiers emitted from the bridge join
notifiers, it becomes so generic that sja1105 does not need to do
anything anymore, we can just delete its implementation of the
.crosschip_bridge_{join,leave} methods.

Among other things we can simply delete is the home-grown implementation
of sja1105_notify_crosschip_switches(). The reason why that is wrong is
because it is not quadratic - it only covers remote switches to which we
have a cross-chip bridging link and that does not cover in-between
switches. This deletion is part of the same patch because sja1105 used
to poke deep inside the guts of the tag_8021q context in order to do
that. Because the cross-chip links went away, so needs the sja1105 code.

Last but not least, dsa_8021q_setup_port() is simplified (and also
renamed). Because our TAG_8021Q_VLAN_ADD notifier is designed to react
on the CPU port too, the four dsa_8021q_vid_apply() calls:
- 1 for RX VLAN on user port
- 1 for the user port's RX VLAN on the CPU port
- 1 for TX VLAN on user port
- 1 for the user port's TX VLAN on the CPU port

now get squashed into only 2 notifier calls via
dsa_port_tag_8021q_vlan_add.

And because the notifiers to add and to delete a tag_8021q VLAN are
distinct, now we finally break up the port setup and teardown into
separate functions instead of relying on a "bool enabled" flag which
tells us what to do. Arguably it should have been this way from the
get go.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean e19cc13c9c net: dsa: tag_8021q: manage RX VLANs dynamically at bridge join/leave time
There has been at least one wasted opportunity for tag_8021q to be used
by a driver:

https://patchwork.ozlabs.org/project/netdev/patch/20200710113611.3398-3-kurt@linutronix.de/#2484272

because of a design decision: the declared purpose of tag_8021q is to
offer source port/switch identification for a tagging driver for packets
coming from a switch with no hardware DSA tagging support. It is not
intended to provide VLAN-based port isolation, because its first user,
sja1105, had another mechanism for bridging domain isolation, the L2
Forwarding Table. So even if 2 ports are in the same VLAN but they are
separated via the L2 Forwarding Table, they will not communicate with
one another. The L2 Forwarding Table is managed by the
sja1105_bridge_join() and sja1105_bridge_leave() methods.

As a consequence, today tag_8021q does not bother too much with hooking
into .port_bridge_join() and .port_bridge_leave() because that would
introduce yet another degree of freedom, it just iterates statically
through all ports of a switch and adds the RX VLAN of one port to all
the others. In this way, whenever .port_bridge_join() is called,
bridging will magically work because the RX VLANs are already installed
everywhere they need to be.

This is not to say that the reason for the change in this patch is to
satisfy the hellcreek and similar use cases, that is merely a nice side
effect. Instead it is to make sja1105 cross-chip links work properly
over a DSA link.

For context, sja1105 today supports a degenerate form of cross-chip
bridging, where the switches are interconnected through their CPU ports
("disjoint trees" topology). There is some code which has been
generalized into dsa_8021q_crosschip_link_{add,del}, but it is not
enough, and frankly it is impossible to build upon that.
Real multi-switch DSA trees, like daisy chains or H trees, which have
actual DSA links, do not work.

The problem is that sja1105 is unlike mv88e6xxx, and does not have a PVT
for cross-chip bridging, which is a table by which the local switch can
select the forwarding domain for packets from a certain ingress switch
ID and source port. The sja1105 switches cannot parse their own DSA
tags, because, well, they don't really have support for DSA tags, it's
all VLANs.

So to make something like cross-chip bridging between sw0p0 and sw1p0 to
work over the sw0p3/sw1p3 DSA link to work with sja1105 in the topology
below:

                         |                                  |
    sw0p0     sw0p1     sw0p2     sw0p3          sw1p3     sw1p2     sw1p1     sw1p0
 [  user ] [  user ] [  cpu  ] [  dsa  ] ---- [  dsa  ] [  cpu  ] [  user ] [  user ]

we need to ask ourselves 2 questions:

(1) how should the L2 Forwarding Table be managed?
(2) how should the VLAN Lookup Table be managed?

i.e. what should prevent packets from going to unwanted ports?

Since as mentioned, there is no PVT, the L2 Forwarding Table only
contains forwarding rules for local ports. So we can say "all user ports
are allowed to forward to all CPU ports and all DSA links".

If we allow forwarding to DSA links unconditionally, this means we must
prevent forwarding using the VLAN Lookup Table. This is in fact
asymmetric with what we do for tag_8021q on ports local to the same
switch, and it matters because now that we are making tag_8021q a core
DSA feature, we need to hook into .crosschip_bridge_join() to add/remove
the tag_8021q VLANs. So for symmetry it makes sense to manage the VLANs
for local forwarding in the same way as cross-chip forwarding.

Note that there is a very precise reason why tag_8021q hooks into
dsa_switch_bridge_join() which acts at the cross-chip notifier level,
and not at a higher level such as dsa_port_bridge_join(). We need to
install the RX VLAN of the newly joining port into the VLAN table of all
the existing ports across the tree that are part of the same bridge, and
the notifier already does the iteration through the switches for us.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean 328621f613 net: dsa: tag_8021q: absorb dsa_8021q_setup into dsa_tag_8021q_{,un}register
Right now, setting up tag_8021q is a 2-step operation for a driver,
first the context structure needs to be created, then the VLANs need to
be installed on the ports. A similar thing is true for teardown.

Merge the 2 steps into the register/unregister methods, to be as
transparent as possible for the driver as to what tag_8021q does behind
the scenes. This also gets rid of the funny "bool setup == true means
setup, == false means teardown" API that tag_8021q used to expose.

Note that dsa_tag_8021q_register() must be called at least in the
.setup() driver method and never earlier (like in the driver probe
function). This is because the DSA switch tree is not initialized at
probe time, and the cross-chip notifiers will not work.

For symmetry with .setup(), the unregister method should be put in
.teardown().

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean 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>
2021-07-20 06:36:42 -07:00
Vladimir Oltean 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:

                                             |
    sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
 [  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
                                   |
                                   +---------+
                                             |
    sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
 [  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
                                   |
                                   +---------+
                                             |
    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
5899ee367a ("net: dsa: tag_8021q: add a context structure") which made
the driver-facing tag_8021q API use "ctx" instead of "ds". Now that we
can access "ctx" directly from "ds", this is no longer needed.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean 8b6e638b4b net: dsa: build tag_8021q.c as part of DSA core
Upcoming patches will add tag_8021q related logic to switch.c and
port.c, in order to allow it to make use of cross-chip notifiers.
In addition, a struct dsa_8021q_context *ctx pointer will be added to
struct dsa_switch.

It seems fairly low-reward to #ifdef the *ctx from struct dsa_switch and
to provide shim implementations of the entire tag_8021q.c calling
surface (not even clear what to do about the tag_8021q cross-chip
notifiers to avoid compiling them). The runtime overhead for switches
which don't use tag_8021q is fairly small because all helpers will check
for ds->tag_8021q_ctx being a NULL pointer and stop there.

So let's make it part of dsa_core.o.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean cedf467064 net: dsa: tag_8021q: create dsa_tag_8021q_{register,unregister} helpers
In preparation of moving tag_8021q to core DSA, move all initialization
and teardown related to tag_8021q which is currently done by drivers in
2 functions called "register" and "unregister". These will gather more
functionality in future patches, which will better justify the chosen
naming scheme.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean 69ebb37064 net: dsa: tag_8021q: use symbolic error names
Use %pe to give the user a string holding the error code instead of just
a number.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean a81a45744b net: dsa: tag_8021q: use "err" consistently instead of "rc"
Some of the tag_8021q code has been taken out of sja1105, which uses
"rc" for its return code variables, whereas the DSA core uses "err".
Change tag_8021q for consistency.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean 0fac6aa098 net: dsa: sja1105: delete the best_effort_vlan_filtering mode
Simply put, the best-effort VLAN filtering mode relied on VLAN retagging
from a bridge VLAN towards a tag_8021q sub-VLAN in order to be able to
decode the source port in the tagger, but the VLAN retagging
implementation inside the sja1105 chips is not the best and we were
relying on marginal operating conditions.

The most notable limitation of the best-effort VLAN filtering mode is
its incapacity to treat this case properly:

ip link add br0 type bridge vlan_filtering 1
ip link set swp2 master br0
ip link set swp4 master br0
bridge vlan del dev swp4 vid 1
bridge vlan add dev swp4 vid 1 pvid

When sending an untagged packet through swp2, the expectation is for it
to be forwarded to swp4 as egress-tagged (so it will contain VLAN ID 1
on egress). But the switch will send it as egress-untagged.

There was an attempt to fix this here:
https://patchwork.kernel.org/project/netdevbpf/patch/20210407201452.1703261-2-olteanv@gmail.com/

but it failed miserably because it broke PTP RX timestamping, in a way
that cannot be corrected due to hardware issues related to VLAN
retagging.

So with either PTP broken or pushing VLAN headers on egress for untagged
packets being broken, the sad reality is that the best-effort VLAN
filtering code is broken. Delete it.

Note that this means there will be a temporary loss of functionality in
this driver until it is replaced with something better (network stack
RX/TX capability for "mode 2" as described in
Documentation/networking/dsa/sja1105.rst, the "port under VLAN-aware
bridge" case). We simply cannot keep this code until that driver rework
is done, it is super bloated and tangled with tag_8021q.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:36:42 -07:00
Vladimir Oltean bcb9928a15 net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave()
This was not caught because there is no switch driver which implements
the .port_bridge_join but not .port_bridge_leave method, but it should
nonetheless be fixed, as in certain conditions (driver development) it
might lead to NULL pointer dereference.

Fixes: f66a6a69f9 ("net: dsa: permit cross-chip bridging between all trees in the system")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-13 14:47:10 -07:00
Vladimir Oltean b71d098715 net: dsa: return -EOPNOTSUPP when driver does not implement .port_lag_join
The DSA core has a layered structure, and even though we end up
returning 0 (success) to user space when setting a bonding/team upper
that can't be offloaded, some parts of the framework actually need to
know that we couldn't offload that.

For example, if dsa_switch_lag_join returns 0 as it currently does,
dsa_port_lag_join has no way to tell a successful offload from a
software fallback, and it will call dsa_port_bridge_join afterwards.
Then we'll think we're offloading the bridge master of the LAG, when in
fact we're not even offloading the LAG. In turn, this will make us set
skb->offload_fwd_mark = true, which is incorrect and the bridge doesn't
like it.

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>
2021-07-01 11:29:42 -07:00
Vladimir Oltean 63c51453c8 net: dsa: replay the local bridge FDB entries pointing to the bridge dev too
When we join a bridge that already has some local addresses pointing to
itself, we do not get those notifications. Similarly, when we leave that
bridge, we do not get notifications for the deletion of those entries.
The only switchdev notifications we get are those of entries added while
the DSA port is enslaved to the bridge.

This makes use cases such as the following work properly (with the
number of additions and removals properly balanced):

ip link add br0 type bridge
ip link add br1 type bridge
ip link set br0 address 00:01:02:03:04:05
ip link set br1 address 00:01:02:03:04:05
ip link set swp0 up
ip link set swp1 up
ip link set swp0 master br0
ip link set swp1 master br1
ip link set br0 up
ip link set br1 up
ip link del br1 # 00:01:02:03:04:05 still installed on the CPU port
ip link del br0 # 00:01:02:03:04:05 finally removed from the CPU port

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 4bed397c3e net: dsa: ensure during dsa_fdb_offload_notify that dev_hold and dev_put are on the same dev
When
(a) "dev" is a bridge port which the DSA switch tree offloads, but is
    otherwise not a dsa slave (such as a LAG netdev), or
(b) "dev" is the bridge net device itself

then strange things happen to the dev_hold/dev_put pair:
dsa_schedule_work() will still be called with a DSA port that offloads
that netdev, but dev_hold() will be called on the non-DSA netdev.
Then the "if" condition in dsa_slave_switchdev_event_work() does not
pass, because "dev" is not a DSA netdev, so dev_put() is not called.

This results in the simple fact that we have a reference counting
mismatch on the "dev" net device.

This can be seen when we add support for host addresses installed on the
bridge net device.

ip link add br1 type bridge
ip link set br1 address 00:01:02:03:04:05
ip link set swp0 master br1
ip link del br1
[  968.512278] unregister_netdevice: waiting for br1 to become free. Usage count = 5

It seems foolish to do penny pinching and not add the net_device pointer
in the dsa_switchdev_event_work structure, so let's finally do that.
As an added bonus, when we start offloading local entries pointing
towards the bridge, these will now properly appear as 'offloaded' in
'bridge fdb' (this was not possible before, because 'dev' was assumed to
only be a DSA net device):

00:01:02:03:04:05 dev br0 vlan 1 offload master br0 permanent
00:01:02:03:04:05 dev br0 offload master br0 permanent

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 81a619f787 net: dsa: include fdb entries pointing to bridge in the host fdb list
The bridge supports a legacy way of adding local (non-forwarded) FDB
entries, which works on an individual port basis:

bridge fdb add dev swp0 00:01:02:03:04:05 master local

As well as a new way, added by Roopa Prabhu in commit 3741873b4f
("bridge: allow adding of fdb entries pointing to the bridge device"):

bridge fdb add dev br0 00:01:02:03:04:05 self local

The two commands are functionally equivalent, except that the first one
produces an entry with fdb->dst == swp0, and the other an entry with
fdb->dst == NULL. The confusing part, though, is that even if fdb->dst
is swp0 for the 'local on port' entry, that destination is not used.

Nonetheless, the idea is that the bridge has reference counting for
local entries, and local entries pointing towards the bridge are still
'as local' as local entries for a port.

The bridge adds the MAC addresses of the interfaces automatically as
FDB entries with is_local=1. For the MAC address of the ports, fdb->dst
will be equal to the port, and for the MAC address of the bridge,
fdb->dst will point towards the bridge (i.e. be NULL). Therefore, if the
MAC address of the bridge is not inherited from either of the physical
ports, then we must explicitly catch local FDB entries emitted towards
the br0, otherwise we'll miss the MAC address of the bridge (and, of
course, any entry with 'bridge add dev br0 ... self local').

Co-developed-by: Tobias Waldekranz <tobias@waldekranz.com>
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>
2021-06-29 10:46:23 -07:00
Tobias Waldekranz 10fae4ac89 net: dsa: include bridge addresses which are local in the host fdb list
The bridge automatically creates local (not forwarded) fdb entries
pointing towards physical ports with their interface MAC addresses.
For switchdev, the significance of these fdb entries is the exact
opposite of that of non-local entries: instead of sending these frame
outwards, we must send them inwards (towards the host).

NOTE: The bridge's own MAC address is also "local". If that address is
not shared with any port, the bridge's MAC is not be added by this
functionality - but the following commit takes care of that case.

NOTE 2: We mark these addresses as host-filtered regardless of the value
of ds->assisted_learning_on_cpu_port. This is because, as opposed to the
speculative logic done for dynamic address learning on foreign
interfaces, the local FDB entries are rather fixed, so there isn't any
risk of them migrating from one bridge port to another.

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>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 3068d466a6 net: dsa: sync static FDB entries on foreign interfaces to hardware
DSA is able to install FDB entries towards the CPU port for addresses
which were dynamically learnt by the software bridge on foreign
interfaces that are in the same bridge with a DSA switch interface.
Since this behavior is opportunistic, it is guarded by the
"assisted_learning_on_cpu_port" property which can be enabled by drivers
and is not done automatically (since certain switches may support
address learning of packets coming from the CPU port).

But if those FDB entries added on the foreign interfaces are static
(added by the user) instead of dynamically learnt, currently DSA does
not do anything (and arguably it should).

Because static FDB entries are not supposed to move on their own, there
is no downside in reusing the "assisted_learning_on_cpu_port" logic to
sync static FDB entries to the DSA CPU port unconditionally, even if
assisted_learning_on_cpu_port is not requested by the driver.

For example, this situation:

   br0
   / \
swp0 dummy0

$ bridge fdb add 02:00:de:ad:00:01 dev dummy0 vlan 1 master static

Results in DSA adding an entry in the hardware FDB, pointing this
address towards the CPU port.

The same is true for entries added to the bridge itself, e.g:

$ bridge fdb add 02:00:de:ad:00:01 dev br0 vlan 1 self local

(except that right now, DSA still ignores 'local' FDB entries, this will
be changed in a later patch)

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>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 26ee7b06a4 net: dsa: install the host MDB and FDB entries in the master's RX filter
If the DSA master implements strict address filtering, then the unicast
and multicast addresses kept by the DSA CPU ports should be synchronized
with the address lists of the DSA master.

Note that we want the synchronization of the master's address lists even
if the DSA switch doesn't support unicast/multicast database operations,
on the premises that the packets will be flooded to the CPU in that
case, and we should still instruct the master to receive them. This is
why we do the dev_uc_add() etc first, even if dsa_port_notify() returns
-EOPNOTSUPP. In turn, dev_uc_add() and friends return error only if
memory allocation fails, so it is probably ok to check and propagate
that error code and not just ignore it.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 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>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 3dc80afc50 net: dsa: introduce a separate cross-chip notifier type for host FDBs
DSA treats some bridge FDB entries by trapping them to the CPU port.
Currently, the only class of such entries are FDB addresses learnt by
the software bridge on a foreign interface. However there are many more
to be added:

- FDB entries with the is_local flag (for termination) added by the
  bridge on the user ports (typically containing the MAC address of the
  bridge port)
- FDB entries pointing towards the bridge net device (for termination).
  Typically these contain the MAC address of the bridge net device.
- Static FDB entries installed on a foreign interface that is in the
  same bridge with a DSA user port.

The reason why a separate cross-chip notifier for host FDBs is justified
compared to normal FDBs is the same as in the case of host MDBs: the
cross-chip notifier matching function in switch.c should avoid
installing these entries on routing ports that route towards the
targeted switch, but not towards the CPU. This is required in order to
have proper support for H-like multi-chip topologies.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 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.

                                                    |
           sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
        [  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
        [   x   ] [       ] [       ] [       ] [       ]
                                          |
                                          +---------+
                                                    |
           sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
        [  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
        [       ] [       ] [       ] [       ] [   x   ]
                                          |
                                          +---------+
                                                    |
           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:

                                                    |
           sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
        [  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
        [   x   ] [       ] [       ] [       ] [       ]
                                          |
                                          +---------+
                                                    |
           sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
        [  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
        [       ] [       ] [       ] [       ] [       ]
                                          |
                                          +---------+
                                                    |
           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>
2021-06-29 10:46:23 -07:00
Vladimir Oltean b8e997c490 net: dsa: introduce a separate cross-chip notifier type for host MDBs
Commit abd49535c3 ("net: dsa: execute dsa_switch_mdb_add only for
routing port in cross-chip topologies") does a surprisingly good job
even for the SWITCHDEV_OBJ_ID_HOST_MDB use case, where DSA simply
translates a switchdev object received on dp into a cross-chip notifier
for dp->cpu_dp.

To visualize how that works, imagine the daisy chain topology below and
consider a SWITCHDEV_OBJ_ID_HOST_MDB object emitted on sw2p0. How does
the cross-chip notifier know to match on all the right ports (sw0p4, the
dedicated CPU port, sw1p4, an upstream DSA link, and sw2p4, another
upstream DSA link)?

                                                |
       sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
    [  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
    [       ] [       ] [       ] [       ] [   x   ]
                                      |
                                      +---------+
                                                |
       sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
    [  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
    [       ] [       ] [       ] [       ] [   x   ]
                                      |
                                      +---------+
                                                |
       sw2p0     sw2p1     sw2p2     sw2p3     sw2p4
    [  user ] [  user ] [  user ] [  user ] [  dsa  ]
    [       ] [       ] [       ] [       ] [   x   ]

The answer is simple: the dedicated CPU port of sw2p0 is sw0p4, and
dsa_routing_port returns the upstream port for all switches.

That is fine, but there are other topologies where this does not work as
well. There are trees with "H" topologies in the wild, where there are 2
or more switches with DSA links between them, but every switch has its
dedicated CPU port. For these topologies, it seems stupid for the neighbor
switches to install an MDB entry on the routing port, since these
multicast addresses are fundamentally different than the usual ones we
support (and that is the justification for this patch, to introduce the
concept of a termination plane multicast MAC address, as opposed to a
forwarding plane multicast MAC address).

For example, when a SWITCHDEV_OBJ_ID_HOST_MDB would get added to sw0p0,
without this patch, it would get treated as a regular port MDB on sw0p2
and it would match on the ports below (including the sw1p3 routing port).

                         |                                  |
    sw0p0     sw0p1     sw0p2     sw0p3          sw1p3     sw1p2     sw1p1     sw1p0
 [  user ] [  user ] [  cpu  ] [  dsa  ]      [  dsa  ] [  cpu  ] [  user ] [  user ]
 [       ] [       ] [   x   ] [       ] ---- [   x   ] [       ] [       ] [       ]

With the patch, the host MDB notifier on sw0p0 matches only on the local
switch, which is what we want for a termination plane address.

                         |                                  |
    sw0p0     sw0p1     sw0p2     sw0p3          sw1p3     sw1p2     sw1p1     sw1p0
 [  user ] [  user ] [  cpu  ] [  dsa  ]      [  dsa  ] [  cpu  ] [  user ] [  user ]
 [       ] [       ] [   x   ] [       ] ---- [       ] [       ] [       ] [       ]

Name this new matching function "dsa_switch_host_address_match" since we
will be reusing it soon for host FDB entries as well.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 10:46:23 -07:00
Vladimir Oltean b117e1e8a8 net: dsa: delete dsa_legacy_fdb_add and dsa_legacy_fdb_del
We want to add reference counting for FDB entries in cross-chip
topologies, and in order for that to have any chance of working and not
be unbalanced (leading to entries which are never deleted), we need to
ensure that higher layers are sane, because if they aren't, it's garbage
in, garbage out.

For example, if we add a bridge FDB entry twice, the bridge properly
errors out:

$ bridge fdb add dev swp0 00:01:02:03:04:07 master static
$ bridge fdb add dev swp0 00:01:02:03:04:07 master static
RTNETLINK answers: File exists

However, the same thing cannot be said about the bridge bypass
operations:

$ bridge fdb add dev swp0 00:01:02:03:04:07
$ bridge fdb add dev swp0 00:01:02:03:04:07
$ bridge fdb add dev swp0 00:01:02:03:04:07
$ bridge fdb add dev swp0 00:01:02:03:04:07
$ echo $?
0

But one 'bridge fdb del' is enough to remove the entry, no matter how
many times it was added.

The bridge bypass operations are impossible to maintain in these
circumstances and lack of support for reference counting the cross-chip
notifiers is holding us back from making further progress, so just drop
support for them. The only way left for users to install static bridge
FDB entries is the proper one, using the "master static" flags.

With this change, rtnl_fdb_add() falls back to calling
ndo_dflt_fdb_add() which uses the duplicate-exclusive variant of
dev_uc_add(): dev_uc_add_excl(). Because DSA does not (yet) declare
IFF_UNICAST_FLT, this results in us going to promiscuous mode:

$ bridge fdb add dev swp0 00:01:02:03:04:05
[   28.206743] device swp0 entered promiscuous mode
$ bridge fdb add dev swp0 00:01:02:03:04:05
RTNETLINK answers: File exists

So even if it does not completely fail, there is at least some indication
that it is behaving differently from before, and closer to user space
expectations, I would argue (the lack of a "local|static" specifier
defaults to "local", or "host-only", so dev_uc_add() is a reasonable
default implementation). If the generic implementation of .ndo_fdb_add
provided by Vlad Yasevich is a proof of anything, it only proves that
the implementation provided by DSA was always wrong, by not looking at
"ndm->ndm_state & NUD_NOARP" (the "static" flag which means that the FDB
entry points outwards) and "ndm->ndm_state & NUD_PERMANENT" (the "local"
flag which means that the FDB entry points towards the host). It all
used to mean the same thing to DSA.

Update the documentation so that the users are not confused about what's
going on.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 10:46:23 -07:00
Vladimir Oltean 7491894532 net: dsa: replay a deletion of switchdev objects for ports leaving a bridged LAG
When a DSA switch port leaves a bonding interface that is under a
bridge, there might be dangling switchdev objects on that port left
behind, because the bridge is not aware that its lower interface (the
bond) changed state in any way.

Call the bridge replay helpers with adding=false before changing
dp->bridge_dev to NULL, because we need to simulate to
dsa_slave_port_obj_del() that these notifications were emitted by the
bridge.

We add this hook to the NETDEV_PRECHANGEUPPER event handler, because
we are calling into switchdev (and the __switchdev_handle_port_obj_del
fanout helpers expect the upper/lower adjacency lists to still be valid)
and PRECHANGEUPPER is the last moment in time when they still are.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28 14:09:03 -07:00
Vladimir Oltean 4ede74e73b net: dsa: refactor the prechangeupper sanity checks into a dedicated function
We need to add more logic to the DSA NETDEV_PRECHANGEUPPER event
handler, more exactly we need to request an unsync of switchdev objects.
In order to fit more code, refactor the existing logic into a helper.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28 14:09:03 -07:00
Vladimir Oltean 7e8c18586d net: bridge: allow the switchdev replay functions to be called for deletion
When a switchdev port leaves a LAG that is a bridge port, the switchdev
objects and port attributes offloaded to that port are not removed:

ip link add br0 type bridge
ip link add bond0 type bond mode 802.3ad
ip link set swp0 master bond0
ip link set bond0 master br0
bridge vlan add dev bond0 vid 100
ip link set swp0 nomaster

VLAN 100 will remain installed on swp0 despite it going into standalone
mode, because as far as the bridge is concerned, nothing ever happened
to its bridge port.

Let's extend the bridge vlan, fdb and mdb replay functions to take a
'bool adding' argument, and make DSA and ocelot call the replay
functions with 'adding' as false from the switchdev unsync path, for the
switch port that leaves the bridge.

Note that this patch in itself does not salvage anything, because in the
current pull mode of operation, DSA still needs to call the replay
helpers with adding=false. This will be done in another patch.

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>
2021-06-28 14:09:03 -07:00
Vladimir Oltean 0d2cfbd41c net: bridge: ignore switchdev events for LAG ports which didn't request replay
There is a slight inconvenience in the switchdev replay helpers added
recently, and this is when:

ip link add br0 type bridge
ip link add bond0 type bond
ip link set bond0 master br0
bridge vlan add dev bond0 vid 100
ip link set swp0 master bond0
ip link set swp1 master bond0

Since the underlying driver (currently only DSA) asks for a replay of
VLANs when swp0 and swp1 join the LAG because it is bridged, what will
happen is that DSA will try to react twice on the VLAN event for swp0.
This is not really a huge problem right now, because most drivers accept
duplicates since the bridge itself does, but it will become a problem
when we add support for replaying switchdev object deletions.

Let's fix this by adding a blank void *ctx in the replay helpers, which
will be passed on by the bridge in the switchdev notifications. If the
context is NULL, everything is the same as before. But if the context is
populated with a valid pointer, the underlying switchdev driver
(currently DSA) can use the pointer to 'see through' the bridge port
(which in the example above is bond0) and 'know' that the event is only
for a particular physical port offloading that bridge port, and not for
all of them.

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>
2021-06-28 14:09:03 -07:00
Vladimir Oltean 69bfac968a net: switchdev: add a context void pointer to struct switchdev_notifier_info
In the case where the driver asks for a replay of a certain type of
event (port object or attribute) for a bridge port that is a LAG, it may
do so because this port has just joined the LAG.

But there might already be other switchdev ports in that LAG, and it is
preferable that those preexisting switchdev ports do not act upon the
replayed event.

The solution is to add a context to switchdev events, which is NULL most
of the time (when the bridge layer initiates the call) but which can be
set to a value controlled by the switchdev driver when a replay is
requested. The driver can then check the context to figure out if all
ports within the LAG should act upon the switchdev event, or just the
ones that match the context.

We have to modify all switchdev_handle_* helper functions as well as the
prototypes in the drivers that use these helpers too, because these
helpers hide the underlying struct switchdev_notifier_info from us and
there is no way to retrieve the context otherwise.

The context structure will be populated and used in later patches.

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>
2021-06-28 14:09:03 -07:00
Vladimir Oltean f9bcdc362c net: dsa: remove cross-chip support from the MRP notifiers
With MRP hardware assist being supported only by the ocelot switch
family, which by design does not support cross-chip bridging, the
current match functions are at best a guess and have not been confirmed
in any way to do anything relevant in a multi-switch topology.

Drop the code and make the notifiers match only on the targeted switch
port.

Cc: Horatiu Vultur <horatiu.vultur@microchip.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>
2021-06-21 12:50:20 -07:00
Vladimir Oltean 88faba20e2 net: dsa: targeted MTU notifiers should only match on one port
dsa_slave_change_mtu() calls dsa_port_mtu_change() twice:
- it sends a cross-chip notifier with the MTU of the CPU port which is
  used to update the DSA links.
- it sends one targeted MTU notifier which is supposed to only match the
  user port on which we are changing the MTU. The "propagate_upstream"
  variable is used here to bypass the cross-chip notifier system from
  switch.c

But due to a mistake, the second, targeted notifier matches not only on
the user port, but also on the DSA link which is a member of the same
switch, if that exists.

And because the DSA links of the entire dst were programmed in a
previous round to the largest_mtu via a "propagate_upstream == true"
notification, then the dsa_port_mtu_change(propagate_upstream == false)
call that is immediately upcoming will break the MTU on the one DSA link
which is chip-wise local to the dp whose MTU is changing right now.

Example given this daisy chain topology:

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  cpu  ] [  user ] [  user ] [  dsa  ] [  user ]
[   x   ] [       ] [       ] [   x   ] [       ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]

ip link set sw0p1 mtu 9000
ip link set sw1p1 mtu 9000 # at this stage, sw0p1 and sw1p1 can talk
                           # to one another using jumbo frames
ip link set sw0p2 mtu 1500 # this programs the sw0p3 DSA link first to
                           # the largest_mtu of 9000, then reprograms it to
                           # 1500 with the "propagate_upstream == false"
                           # notifier, breaking communication between
                           # sw0p1 and sw1p1

To escape from this situation, make the targeted match really match on a
single port - the user port, and rename the "propagate_upstream"
variable to "targeted_match" to clarify the intention and avoid future
issues.

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>
2021-06-21 12:50:20 -07:00
Vladimir Oltean 4e4ab79500 net: dsa: calculate the largest_mtu across all ports in the tree
If we have a cross-chip topology like this:

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  cpu  ] [  user ] [  user ] [  dsa  ] [  user ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]

and we issue the following commands:

1. ip link set sw0p1 mtu 1700
2. ip link set sw1p1 mtu 1600

we notice the following happening:

Command 1. emits a non-targeted MTU notifier for the CPU port (sw0p0)
with the largest_mtu calculated across switch 0, of 1700. This matches
sw0p0, sw0p3 and sw1p4 (all CPU ports and DSA links).
Then, it emits a targeted MTU notifier for the user port (sw0p1), again
with MTU 1700 (this doesn't matter).

Command 2. emits a non-targeted MTU notifier for the CPU port (sw0p0)
with the largest_mtu calculated across switch 1, of 1600. This matches
the same group of ports as above, and decreases the MTU for the CPU port
and the DSA links from 1700 to 1600.

As a result, the sw0p1 user port can no longer communicate with its CPU
port at MTU 1700.

To address this, we should calculate the largest_mtu across all switches
that may share a CPU port, and only emit MTU notifiers with that value.

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>
2021-06-21 12:50:20 -07:00
Vladimir Oltean abd49535c3 net: dsa: execute dsa_switch_mdb_add only for routing port in cross-chip topologies
Currently, the notifier for adding a multicast MAC address matches on
the targeted port and on all DSA links in the system, be they upstream
or downstream links.

This leads to a considerable amount of useless traffic.

Consider this daisy chain topology, and a MDB add notifier emitted on
sw0p0. It matches on sw0p0, sw0p3, sw1p3 and sw2p4.

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
[   x   ] [       ] [       ] [   x   ] [       ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
[       ] [       ] [       ] [   x   ] [   x   ]
                                  |
                                  +---------+
                                            |
   sw2p0     sw2p1     sw2p2     sw2p3     sw2p4
[  user ] [  user ] [  user ] [  user ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]

But switch 0 has no reason to send the multicast traffic for that MAC
address on sw0p3, which is how it reaches switches 1 and 2. Those
switches don't expect, according to the user configuration, to receive
this multicast address from switch 1, and they will drop it anyway,
because the only valid destination is the port they received it on.
They only need to configure themselves to deliver that multicast address
_towards_ switch 1, where the MDB entry is installed.

Similarly, switch 1 should not send this multicast traffic towards
sw1p3, because that is how it reaches switch 2.

With this change, the heat map for this MDB notifier changes as follows:

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
[   x   ] [       ] [       ] [       ] [       ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]
                                  |
                                  +---------+
                                            |
   sw2p0     sw2p1     sw2p2     sw2p3     sw2p4
[  user ] [  user ] [  user ] [  user ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]

Now the mdb notifier behaves the same as the fdb notifier.

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>
2021-06-21 12:50:20 -07:00
Vladimir Oltean 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>
2021-06-21 12:50:20 -07:00
Vladimir Oltean 8674f8d310 net: dsa: assert uniqueness of dsa,member properties
The cross-chip notifiers work by comparing each ds->index against the
info->sw_index value from the notifier. The ds->index is retrieved from
the device tree dsa,member property.

If a single tree cross-chip topology does not declare unique switch IDs,
this will result in hard-to-debug issues/voodoo effects such as the
cross-chip notifier for one switch port also matching the port with the
same number from another switch.

Check in dsa_switch_parse_member_of() whether the DSA switch tree
contains a DSA switch with the index we're preparing to add, before
actually adding 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>
2021-06-21 12:50:20 -07:00
Oleksij Rempel c916e8e1ea net: dsa: dsa_slave_phy_connect(): extend phy's flags with port specific phy flags
The current get_phy_flags() is only processed when we connect to a PHY
via a designed phy-handle property via phylink_of_phy_connect(), but if
we fallback on the internal MDIO bus created by a switch and take the
dsa_slave_phy_connect() path then we would not be processing that flag
and using it at PHY connection time.

Suggested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-14 12:54:43 -07:00
Vladimir Oltean 566b18c8b7 net: dsa: sja1105: implement TX timestamping for SJA1110
The TX timestamping procedure for SJA1105 is a bit unconventional
because the transmit procedure itself is unconventional.

Control packets (and therefore PTP as well) are transmitted to a
specific port in SJA1105 using "management routes" which must be written
over SPI to the switch. These are one-shot rules that match by
destination MAC address on traffic coming from the CPU port, and select
the precise destination port for that packet. So to transmit a packet
from NET_TX softirq context, we actually need to defer to a process
context so that we can perform that SPI write before we send the packet.
The DSA master dev_queue_xmit() runs in process context, and we poll
until the switch confirms it took the TX timestamp, then we annotate the
skb clone with that TX timestamp. This is why the sja1105 driver does
not need an skb queue for TX timestamping.

But the SJA1110 is a bit (not much!) more conventional, and you can
request 2-step TX timestamping through the DSA header, as well as give
the switch a cookie (timestamp ID) which it will give back to you when
it has the timestamp. So now we do need a queue for keeping the skb
clones until their TX timestamps become available.

The interesting part is that the metadata frames from SJA1105 haven't
disappeared completely. On SJA1105 they were used as follow-ups which
contained RX timestamps, but on SJA1110 they are actually TX completion
packets, which contain a variable (up to 32) array of timestamps.
Why an array? Because:
- not only is the TX timestamp on the egress port being communicated,
  but also the RX timestamp on the CPU port. Nice, but we don't care
  about that, so we ignore it.
- because a packet could be multicast to multiple egress ports, each
  port takes its own timestamp, and the TX completion packet contains
  the individual timestamps on each port.

This is unconventional because switches typically have a timestamping
FIFO and raise an interrupt, but this one doesn't. So the tagger needs
to detect and parse meta frames, and call into the main switch driver,
which pairs the timestamps with the skbs in the TX timestamping queue
which are waiting for one.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 12:45:38 -07:00
Vladimir Oltean 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>
2021-06-11 12:45:38 -07:00
Vladimir Oltean 617ef8d937 net: dsa: sja1105: make SJA1105_SKB_CB fit a full timestamp
In SJA1105, RX timestamps for packets sent to the CPU are transmitted in
separate follow-up packets (metadata frames). These contain partial
timestamps (24 or 32 bits) which are kept in SJA1105_SKB_CB(skb)->meta_tstamp.

Thankfully, SJA1110 improved that, and the RX timestamps are now
transmitted in-band with the actual packet, in the timestamp trailer.
The RX timestamps are now full-width 64 bits.

Because we process the RX DSA tags in the rcv() method in the tagger,
but we would like to preserve the DSA code structure in that we populate
the skb timestamp in the port_rxtstamp() call which only happens later,
the implication is that we must somehow pass the 64-bit timestamp from
the rcv() method all the way to port_rxtstamp(). We can use the skb->cb
for that.

Rename the meta_tstamp from struct sja1105_skb_cb from "meta_tstamp" to
"tstamp", and increase its size to 64 bits.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 12:45:38 -07:00
Vladimir Oltean 233697b3b3 net: dsa: tag_8021q: refactor RX VLAN parsing into a dedicated function
The added value of this function is that it can deal with both the case
where the VLAN header is in the skb head, as well as in the offload field.
This is something I was not able to do using other functions in the
network stack.

Since both ocelot-8021q and sja1105 need to do the same stuff, let's
make it a common service provided by tag_8021q.

This is done as refactoring for the new SJA1110 tagger, which partly
uses tag_8021q as well (just like SJA1105), and will be the third caller.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 12:45:38 -07:00
Vladimir Oltean baa3ad08de net: dsa: tag_sja1105: stop resetting network and transport headers
This makes no sense and is not needed, it is probably a debugging
leftover.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 12:45:38 -07:00
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>
2021-06-11 12:45:38 -07:00
Vladimir Oltean 4ef8d857b5 net: dsa: tag_8021q: fix the VLAN IDs used for encoding sub-VLANs
When using sub-VLANs in the range of 1-7, the resulting value from:

	rx_vid = dsa_8021q_rx_vid_subvlan(ds, port, subvlan);

is wrong according to the description from tag_8021q.c:

 | 11  | 10  |  9  |  8  |  7  |  6  |  5  |  4  |  3  |  2  |  1  |  0  |
 +-----------+-----+-----------------+-----------+-----------------------+
 |    DIR    | SVL |    SWITCH_ID    |  SUBVLAN  |          PORT         |
 +-----------+-----+-----------------+-----------+-----------------------+

For example, when ds->index == 0, port == 3 and subvlan == 1,
dsa_8021q_rx_vid_subvlan() returns 1027, same as it returns for
subvlan == 0, but it should have returned 1043.

This is because the low portion of the subvlan bits are not masked
properly when writing into the 12-bit VLAN value. They are masked into
bits 4:3, but they should be masked into bits 5:4.

Fixes: 3eaae1d05f ("net: dsa: tag_8021q: support up to 8 VLANs per port using sub-VLANs")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-01 15:02:05 -07:00
Vladimir Oltean b94cbc909f net: dsa: fix error code getting shifted with 4 in dsa_slave_get_sset_count
DSA implements a bunch of 'standardized' ethtool statistics counters,
namely tx_packets, tx_bytes, rx_packets, rx_bytes. So whatever the
hardware driver returns in .get_sset_count(), we need to add 4 to that.

That is ok, except that .get_sset_count() can return a negative error
code, for example:

b53_get_sset_count
-> phy_ethtool_get_sset_count
   -> return -EIO

-EIO is -5, and with 4 added to it, it becomes -1, aka -EPERM. One can
imagine that certain error codes may even become positive, although
based on code inspection I did not see instances of that.

Check the error code first, if it is negative return it as-is.

Based on a similar patch for dsa_master_get_strings from Dan Carpenter:
https://patchwork.kernel.org/project/netdevbpf/patch/YJaSe3RPgn7gKxZv@mwanda/

Fixes: 91da11f870 ("net: Distributed Switch Architecture protocol support")
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>
2021-05-10 14:36:59 -07:00
Dan Carpenter a269333fa5 net: dsa: fix a crash if ->get_sset_count() fails
If ds->ops->get_sset_count() fails then it "count" is a negative error
code such as -EOPNOTSUPP.  Because "i" is an unsigned int, the negative
error code is type promoted to a very high value and the loop will
corrupt memory until the system crashes.

Fix this by checking for error codes and changing the type of "i" to
just int.

Fixes: badf3ada60 ("net: dsa: Provide CPU port statistics to master netdev")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.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: David S. Miller <davem@davemloft.net>
2021-05-10 14:31:27 -07:00
Oleksij Rempel 4a52dd8fef net: selftest: fix build issue if INET is disabled
In case ethernet driver is enabled and INET is disabled, selftest will
fail to build.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: 3e1e58d64c ("net: add generic selftest support")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210428130947.29649-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-04-28 14:06:45 -07:00
Yangbo Lu 39e5308b32 net: mscc: ocelot: support PTP Sync one-step timestamping
Although HWTSTAMP_TX_ONESTEP_SYNC existed in ioctl for hardware timestamp
configuration, the PTP Sync one-step timestamping had never been supported.

This patch is to truely support it.

- ocelot_port_txtstamp_request()
  This function handles tx timestamp request by storing
  ptp_cmd(tx timestamp type) in OCELOT_SKB_CB(skb)->ptp_cmd,
  and additionally for two-step timestamp storing ts_id in
  OCELOT_SKB_CB(clone)->ptp_cmd.

- ocelot_ptp_rew_op()
  During xmit, this function is called to get rew_op (rewriter option) by
  checking skb->cb for tx timestamp request, and configure to transmitting.

Non-onestep-Sync packet with one-step timestamp request falls back to use
two-step timestamp.

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>
2021-04-27 14:10:15 -07:00
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>
2021-04-27 14:10:15 -07:00
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>
2021-04-27 14:10:15 -07:00
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>
2021-04-27 14:10:15 -07:00
Yangbo Lu cfd12c06cd net: dsa: check tx timestamp request in core driver
Check tx timestamp request in core driver at very beginning of
dsa_skb_tx_timestamp(), so that most skbs not requiring tx
timestamp just return. And drop such checking in device drivers.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Tested-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-27 14:10:15 -07:00
Oleksij Rempel 70a7c484c7 net: dsa: fix bridge support for drivers without port_bridge_flags callback
Starting with patch:
a8b659e7ff ("net: dsa: act as passthrough for bridge port flags")

drivers without "port_bridge_flags" callback will fail to join the bridge.
Looking at the code, -EOPNOTSUPP seems to be the proper return value,
which makes at least microchip and atheros switches work again.

Fixes: 5961d6a12c ("net: dsa: inherit the actual bridge port flags at join time")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-21 10:47:27 -07:00
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>
2021-04-20 16:51:20 -07:00
Tobias Waldekranz 21e0b508c8 net: dsa: Only notify CPU ports of changes to the tag protocol
Previously DSA ports were also included, on the assumption that the
protocol used by the CPU port had to the matched throughout the entire
tree.

As there is not yet any consumer in need of this, drop the call.

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>
2021-04-20 16:51:19 -07:00
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>
2021-04-20 16:08:02 -07:00
Vladimir Oltean 2c4eca3ef7 net: bridge: switchdev: include local flag in FDB notifications
As explained in bugfix commit 6ab4c3117a ("net: bridge: don't notify
switchdev for local FDB addresses") as well as in this discussion:
https://lore.kernel.org/netdev/20210117193009.io3nungdwuzmo5f7@skbuf/

the switchdev notifiers for FDB entries managed to have a zero-day bug,
which was that drivers would not know what to do with local FDB entries,
because they were not told that they are local. The bug fix was to
simply not notify them of those addresses.

Let us now add the 'is_local' bit to bridge FDB entries, and make all
drivers ignore these entries by their own choice.

Co-developed-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:15:45 -07:00
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>
2021-04-13 14:35:02 -07:00
Jakub Kicinski 8859a44ea0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

MAINTAINERS
 - keep Chandrasekar
drivers/net/ethernet/mellanox/mlx5/core/en_main.c
 - simple fix + trust the code re-added to param.c in -next is fine
include/linux/bpf.h
 - trivial
include/linux/ethtool.h
 - trivial, fix kdoc while at it
include/linux/skmsg.h
 - move to relevant place in tcp.c, comment re-wrapped
net/core/skmsg.c
 - add the sk = sk // sk = NULL around calls
net/tipc/crypto.c
 - trivial

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-04-09 20:48:35 -07:00
Maxim Kochetkov fb6ec87f72 net: dsa: Fix type was not set for devlink port
If PHY is not available on DSA port (described at devicetree but absent or
failed to detect) then kernel prints warning after 3700 secs:

[ 3707.948771] ------------[ cut here ]------------
[ 3707.948784] Type was not set for devlink port.
[ 3707.948894] WARNING: CPU: 1 PID: 17 at net/core/devlink.c:8097 0xc083f9d8

We should unregister the devlink port as a user port and
re-register it as an unused port before executing "continue" in case of
dsa_port_setup error.

Fixes: 86f8b1c01a ("net: dsa: Do not make user port errors fatal")
Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-29 13:49:04 -07:00