net: dsa: Use conduit and user terms

Use more inclusive terms throughout the DSA subsystem by moving away
from "master" which is replaced by "conduit" and "slave" which is
replaced by "user". No functional changes.

Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20231023181729.1191071-2-florian.fainelli@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: remove dsa_port_phylink_validate()

As all drivers now provide phylink capabilities (including MAC), the
if() condition in dsa_port_phylink_validate() will always be true. We
will always use the generic validator, which phylink will call itself
if the .validate method isn't populated. Thus, there is now no need to
implement the .validate method, so this implementation can be removed.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: propagate extack to ds->ops->port_hsr_join()

Drivers can provide meaningful error messages which state a reason why
they can't perform an offload, and dsa_slave_changeupper() already has
the infrastructure to propagate these over netlink rather than printing
to the kernel log. So pass the extack argument and modify the xrs700x
driver's port_hsr_join() prototype.

Also take the opportunity and use the extack for the 2 -EOPNOTSUPP cases
from xrs700x_hsr_join().

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: mark parsed interface mode for legacy switch drivers

If we successfully parsed an interface mode with a legacy switch
driver, populate that mode into phylink's supported interfaces rather
than defaulting to the internal and gmii interfaces.

This hasn't caused an issue so far, because when the interface doesn't
match a supported one, phylink_validate() doesn't clear the supported
mask, but instead returns -EINVAL. phylink_parse_fixedlink() doesn't
check this return value, and merely relies on the supported ethtool
link modes mask being cleared. Therefore, the fixed link settings end
up being allowed despite validation failing.

Before this causes a problem, arrange for DSA to more accurately
populate phylink's supported interfaces mask so validation can
correctly succeed.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/E1qTKdM-003Cpx-Eh@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: remove legacy_pre_march2020 detection

All drivers are now updated for the March 2020 changes, and no longer
make use of the mac_pcs_get_state() or mac_an_restart() operations,
which are now NULL across all DSA drivers. All DSA drivers don't look
at speed, duplex, pause or advertisement in their phylink_mac_config()
method either.

Remove support for these operations from DSA, and stop marking DSA as
a legacy driver by default.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: fix older DSA drivers using phylink

Older DSA drivers that do not provide an dsa_ops adjust_link method end
up using phylink. Unfortunately, a recent phylink change that requires
its supported_interfaces bitmap to be filled breaks these drivers
because the bitmap remains empty.

Rather than fixing each driver individually, fix it in the core code so
we have a sensible set of defaults.

Reported-by: Sergei Antonov <saproj@gmail.com>
Fixes: de5c9bf40c45 ("net: phylink: require supported_interfaces to be filled")
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com> # dsa_loop
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/E1qOflM-001AEz-D3@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: add support for mac_prepare() and mac_finish() calls

Add DSA support for the phylink mac_prepare() and mac_finish() calls.
These were introduced as part of the PCS support to allow MACs to
perform preparatory steps prior to configuration, and finalisation
steps after the MAC and PCS has been configured.

Introducing phylink_pcs support to the mv88e6xxx DSA driver needs some
code moved out of its mac_config() stage into the mac_prepare() and
mac_finish() stages, and this commit facilitates such code in DSA
drivers.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: make dsa_port_supports_hwtstamp() construct a fake ifreq

dsa_master_ioctl() is in the process of getting converted to a different
API, where we won't have access to a struct ifreq * anymore, but rather,
to a struct kernel_hwtstamp_config.

Since ds->ops->port_hwtstamp_get() still uses struct ifreq *, this
creates a difficult situation where we have to make up such a dummy
pointer.

The conversion is a bit messy, because it forces a "good" implementation
of ds->ops->port_hwtstamp_get() to return -EFAULT in copy_to_user()
because of the NULL ifr->ifr_data pointer. However, it works, and it is
only a transient step until ds->ops->port_hwtstamp_get() gets converted
to the new API which passes struct kernel_hwtstamp_config and does not
call copy_to_user().

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>

net: dsa: fix db type confusion in host fdb/mdb add/del

We have the following code paths:

Host FDB (unicast RX filtering):

dsa_port_standalone_host_fdb_add() dsa_port_bridge_host_fdb_add()
| |
+--------------+ +------------+
| |
v v
dsa_port_host_fdb_add()

dsa_port_standalone_host_fdb_del() dsa_port_bridge_host_fdb_del()
| |
+--------------+ +------------+
| |
v v
dsa_port_host_fdb_del()

Host MDB (multicast RX filtering):

dsa_port_standalone_host_mdb_add() dsa_port_bridge_host_mdb_add()
| |
+--------------+ +------------+
| |
v v
dsa_port_host_mdb_add()

dsa_port_standalone_host_mdb_del() dsa_port_bridge_host_mdb_del()
| |
+--------------+ +------------+
| |
v v
dsa_port_host_mdb_del()

The logic added by commit 5e8a1e03aa4d ("net: dsa: install secondary
unicast and multicast addresses as host FDB/MDB") zeroes out
db.bridge.num if the switch doesn't support ds->fdb_isolation
(the majority doesn't). This is done for a reason explained in commit
c26933639b54 ("net: dsa: request drivers to perform FDB isolation").

Taking a single code path as example - dsa_port_host_fdb_add() - the
others are similar - the problem is that this function handles:
- DSA_DB_PORT databases, when called from
dsa_port_standalone_host_fdb_add()
- DSA_DB_BRIDGE databases, when called from
dsa_port_bridge_host_fdb_add()

So, if dsa_port_host_fdb_add() were to make any change on the
"bridge.num" attribute of the database, this would only be correct for a
DSA_DB_BRIDGE, and a type confusion for a DSA_DB_PORT bridge.

However, this bug is without consequences, for 2 reasons:

- dsa_port_standalone_host_fdb_add() is only called from code which is
(in)directly guarded by dsa_switch_supports_uc_filtering(ds), and that
function only returns true if ds->fdb_isolation is set. So, the code
only executed for DSA_DB_BRIDGE databases.

- Even if the code was not dead for DSA_DB_PORT, we have the following
memory layout:

struct dsa_bridge {
struct net_device *dev;
unsigned int num;
bool tx_fwd_offload;
refcount_t refcount;
};

struct dsa_db {
enum dsa_db_type type;

union {
const struct dsa_port *dp; // DSA_DB_PORT
struct dsa_lag lag;
struct dsa_bridge bridge; // DSA_DB_BRIDGE
};
};

So, the zeroization of dsa_db :: bridge :: num on a dsa_db structure of
type DSA_DB_PORT would access memory which is unused, because we only
use dsa_db :: dp for DSA_DB_PORT, and this is mapped at the same address
with dsa_db :: dev for DSA_DB_BRIDGE, thanks to the union definition.

It is correct to fix up dsa_db :: bridge :: num only from code paths
that come from the bridge / switchdev, so move these there.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230329133819.697642-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: move tag_8021q headers to their proper place

tag_8021q definitions are all over the place. Some are exported to
linux/dsa/8021q.h (visible by DSA core, taggers, switch drivers and
everyone else), and some are in dsa_priv.h.

Move the structures that don't need external visibility into tag_8021q.c,
and the ones which don't need the world or switch drivers to see them
into tag_8021q.h.

We also have the tag_8021q.h inclusion from switch.c, which is basically
the entire reason why tag_8021q.c was built into DSA in commit
8b6e638b4be2 ("net: dsa: build tag_8021q.c as part of DSA core").
I still don't know how to better deal with that, so leave it alone.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: rename dsa2.c back into dsa.c and create its header

The previous change moved the code into the larger file (dsa2.c) to
minimize the delta. Rename that now to dsa.c, and create dsa.h, where
all related definitions from dsa_priv.h go.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: move headers exported by switch.c to switch.h

Reduce code bloat in dsa_priv.h by moving the prototypes exported by
switch.h into their own header file.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: move headers exported by slave.c to slave.h

Minimize the use of the bloated dsa_priv.h by moving the prototypes
exported by slave.c to their own header file.

This is just approximate to get the code structure right. There are some
interdependencies with static inline code left in dsa_priv.h, so leave
slave.h included from there for now.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: move headers exported by port.c to port.h

Minimize the use of the bloated dsa_priv.h by moving the prototypes
exported by port.c to their own header file.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: remove phylink_validate() method

As of now, no DSA driver uses a custom link mode validation procedure
anymore. So remove this DSA operation and let phylink determine what is
supported based on config->mac_capabilities (if provided by the driver).
Leave a comment why we left the code that we did, and that there is more
work to do.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: make dsa_master_ioctl() see through port_hwtstamp_get() shims

There are multi-generational drivers like mv88e6xxx which have code like
this:

int mv88e6xxx_port_hwtstamp_get(struct dsa_switch *ds, int port,
struct ifreq *ifr)
{
if (!chip->info->ptp_support)
return -EOPNOTSUPP;

...
}

DSA wants to deny PTP timestamping on the master if the switch supports
timestamping too. However it currently relies on the presence of the
port_hwtstamp_get() callback to determine PTP capability, and this
clearly does not work in that case (method is present but returns
-EOPNOTSUPP).

We should not deny PTP on the DSA master for those switches which truly
do not support hardware timestamping.

Create a dsa_port_supports_hwtstamp() method which actually probes for
support by calling port_hwtstamp_get() and seeing whether that returned
-EOPNOTSUPP or not.

Fixes: f685e609a301 ("net: dsa: Deny PTP on master if switch supports it")
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20221110124345.3901389-1-festevam@gmail.com/
Reported-by: Fabio Estevam <festevam@gmail.com>
Reported-by: Steffen Bätz <steffen@innosonix.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: fix wrong pointer passed to PTR_ERR() in dsa_port_phylink_create()

Fix wrong pointer passed to PTR_ERR() in dsa_port_phylink_create() to print
error message.

Fixes: cf5ca4ddc37a ("net: dsa: don't leave dangling pointers in dp->pl when failing")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: don't leave dangling pointers in dp->pl when failing

There is a desire to simplify the dsa_port registration path with
devlink, and this involves reworking a bit how user ports which fail to
connect to their PHY (because it's missing) get reinitialized as UNUSED
devlink ports.

The desire is for the change to look something like this; basically
dsa_port_setup() has failed, we just change dp->type and call
dsa_port_setup() again.

-/* Destroy the current devlink port, and create a new one which has the UNUSED
- * flavour.
- */
-static int dsa_port_reinit_as_unused(struct dsa_port *dp)
+static int dsa_port_setup_as_unused(struct dsa_port *dp)
{
- dsa_port_devlink_teardown(dp);
dp->type = DSA_PORT_TYPE_UNUSED;
- return dsa_port_devlink_setup(dp);
+ return dsa_port_setup(dp);
}

For an UNUSED port, dsa_port_setup() mostly only calls dsa_port_devlink_setup()
anyway, so we could get away with calling just that. But if we call the
full blown dsa_port_setup(dp) (which will be needed to properly set
dp->setup = true), the callee will have the tendency to go through this
code block too, and call dsa_port_disable(dp):

switch (dp->type) {
case DSA_PORT_TYPE_UNUSED:
dsa_port_disable(dp);
break;

That is not very good, because dsa_port_disable() has this hidden inside
of it:

if (dp->pl)
phylink_stop(dp->pl);

Fact is, we are not prepared to handle a call to dsa_port_disable() with
a struct dsa_port that came from a previous (and failed) call to
dsa_port_setup(). We do not clean up dp->pl, and this will make the
second call to dsa_port_setup() call phylink_stop() on a dangling dp->pl
pointer.

Solve this by creating an API for phylink destruction which is symmetric
to the phylink creation, and never leave dp->pl set to anything except
NULL or a valid phylink structure.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: allow masters to join a LAG

There are 2 ways in which a DSA user port may become handled by 2 CPU
ports in a LAG:

(1) its current DSA master joins a LAG

ip link del bond0 && ip link add bond0 type bond mode 802.3ad
ip link set eno2 master bond0

When this happens, all user ports with "eno2" as DSA master get
automatically migrated to "bond0" as DSA master.

(2) it is explicitly configured as such by the user

# Before, the DSA master was eno3
ip link set swp0 type dsa master bond0

The design of this configuration is that the LAG device dynamically
becomes a DSA master through dsa_master_setup() when the first physical
DSA master becomes a LAG slave, and stops being so through
dsa_master_teardown() when the last physical DSA master leaves.

A LAG interface is considered as a valid DSA master only if it contains
existing DSA masters, and no other lower interfaces. Therefore, we
mainly rely on method (1) to enter this configuration.

Each physical DSA master (LAG slave) retains its dev->dsa_ptr for when
it becomes a standalone DSA master again. But the LAG master also has a
dev->dsa_ptr, and this is actually duplicated from one of the physical
LAG slaves, and therefore needs to be balanced when LAG slaves come and
go.

To the switch driver, putting DSA masters in a LAG is seen as putting
their associated CPU ports in a LAG.

We need to prepare cross-chip host FDB notifiers for CPU ports in a LAG,
by calling the driver's ->lag_fdb_add method rather than ->port_fdb_add.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: propagate extack to port_lag_join

Drivers could refuse to offload a LAG configuration for a variety of
reasons, mainly having to do with its TX type. Additionally, since DSA
masters may now also be LAG interfaces, and this will translate into a
call to port_lag_join on the CPU ports, there may be extra restrictions
there. Propagate the netlink extack to this DSA method in order for
drivers to give a meaningful error message back to the user.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: allow the DSA master to be seen and changed through rtnetlink

Some DSA switches have multiple CPU ports, which can be used to improve
CPU termination throughput, but DSA, through dsa_tree_setup_cpu_ports(),
sets up only the first one, leading to suboptimal use of hardware.

The desire is to not change the default configuration but to permit the
user to create a dynamic mapping between individual user ports and the
CPU port that they are served by, configurable through rtnetlink. It is
also intended to permit load balancing between CPU ports, and in that
case, the foreseen model is for the DSA master to be a bonding interface
whose lowers are the physical DSA masters.

To that end, we create a struct rtnl_link_ops for DSA user ports with
the "dsa" kind. We expose the IFLA_DSA_MASTER link attribute that
contains the ifindex of the newly desired DSA master.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: introduce dsa_port_get_master()

There is a desire to support for DSA masters in a LAG.

That configuration is intended to work by simply enslaving the master to
a bonding/team device. But the physical DSA master (the LAG slave) still
has a dev->dsa_ptr, and that cpu_dp still corresponds to the physical
CPU port.

However, we would like to be able to retrieve the LAG that's the upper
of the physical DSA master. In preparation for that, introduce a helper
called dsa_port_get_master() that replaces all occurrences of the
dp->cpu_dp->master pattern. The distinction between LAG and non-LAG will
be made later within the helper itself.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: make phylink-related OF properties mandatory on DSA and CPU ports

Early DSA drivers were kind of simplistic in that they assumed a fairly
narrow hardware layout. User ports would have integrated PHYs at an
internal MDIO address that is derivable from the port number, and shared
(DSA and CPU) ports would have an MII-style (serial or parallel)
connection to another MAC. Phylib and then phylink were used to drive
the internal PHYs, and this needed little to no description through the
platform data structures. Bringing up the shared ports at the maximum
supported link speed was the responsibility of the drivers.

As a result of this, when these early drivers were converted from
platform data to the new DSA OF bindings, there was no link information
translated into the first DT bindings.

https://lore.kernel.org/all/YtXFtTsf++AeDm1l@lunn.ch/

Later, phylink was adopted for shared ports as well, and today we have a
workaround in place, introduced by commit a20f997010c4 ("net: dsa: Don't
instantiate phylink for CPU/DSA ports unless needed"). There, DSA checks
for the presence of phy-handle/fixed-link/managed OF properties, and if
missing, phylink registration would be skipped. This is because phylink
is optional for some drivers (the shared ports already work without it),
but the process of starting to register a port with phylink is
irreversible: if phylink_create() fails to find the fwnode properties it
needs, it bails out and it leaves the ports inoperational (because
phylink expects ports to be initially down, so DSA necessarily takes
them down, and doesn't know how to put them back up again).

DSA being a common framework, new drivers opt into this workaround
willy-nilly, but the ideal behavior from the DSA core's side would have
been to not interfere with phylink's process of failing at all. This
isn't possible because of regression concerns with pre-phylink DT blobs,
but at least DSA should put a stop to the proliferation of more of such
cases that rely on the workaround to skip phylink registration, and
sanitize the environment that new drivers work in.

To that end, create a list of compatible strings for which the
workaround is preserved, and don't apply the workaround for any drivers
outside that list (this includes new drivers).

In some cases, we make the assumption that even existing drivers don't
rely on DSA's workaround, and we do this by looking at the device trees
in which they appear. We can't fully know what is the situation with
downstream DT blobs, but we can guess the overall trend by studying the
DT blobs that were submitted upstream. If there are upstream blobs that
have lacking descriptions, we take it as very likely that there are many
more downstream blobs that do so too. If all upstream blobs have
complete descriptions, we take that as a hint that the driver is a
candidate for enforcing strict DT bindings (considering that most
bindings are copy-pasted). If there are no upstream DT blobs, we take
the conservative route of allowing the workaround, unless the driver
maintainer instructs us otherwise.

The driver situation is as follows:

ar9331
~~~~~~

compatible strings:
- qca,ar9331-switch

1 occurrence in mainline device trees, part of SoC dtsi
(arch/mips/boot/dts/qca/ar9331.dtsi), description is not problematic.

Verdict: opt into strict DT bindings and out of workarounds.

b53
~~~

compatible strings:
- brcm,bcm5325
- brcm,bcm53115
- brcm,bcm53125
- brcm,bcm53128
- brcm,bcm5365
- brcm,bcm5389
- brcm,bcm5395
- brcm,bcm5397
- brcm,bcm5398

- brcm,bcm53010-srab
- brcm,bcm53011-srab
- brcm,bcm53012-srab
- brcm,bcm53018-srab
- brcm,bcm53019-srab
- brcm,bcm5301x-srab
- brcm,bcm11360-srab
- brcm,bcm58522-srab
- brcm,bcm58525-srab
- brcm,bcm58535-srab
- brcm,bcm58622-srab
- brcm,bcm58623-srab
- brcm,bcm58625-srab
- brcm,bcm88312-srab
- brcm,cygnus-srab
- brcm,nsp-srab
- brcm,omega-srab

- brcm,bcm3384-switch
- brcm,bcm6328-switch
- brcm,bcm6368-switch
- brcm,bcm63xx-switch

I've found at least these mainline DT blobs with problems:

arch/arm/boot/dts/bcm47094-linksys-panamera.dts
- lacks phy-mode
arch/arm/boot/dts/bcm47189-tenda-ac9.dts
- lacks phy-mode and fixed-link
arch/arm/boot/dts/bcm47081-luxul-xap-1410.dts
arch/arm/boot/dts/bcm47081-luxul-xwr-1200.dts
arch/arm/boot/dts/bcm47081-buffalo-wzr-600dhp2.dts
- lacks phy-mode and fixed-link
arch/arm/boot/dts/bcm47094-luxul-xbr-4500.dts
arch/arm/boot/dts/bcm4708-smartrg-sr400ac.dts
arch/arm/boot/dts/bcm4708-luxul-xap-1510.dts
arch/arm/boot/dts/bcm953012er.dts
arch/arm/boot/dts/bcm4708-netgear-r6250.dts
arch/arm/boot/dts/bcm4708-buffalo-wzr-1166dhp-common.dtsi
arch/arm/boot/dts/bcm4708-luxul-xwc-1000.dts
arch/arm/boot/dts/bcm47094-luxul-abr-4500.dts
- lacks phy-mode and fixed-link
arch/arm/boot/dts/bcm53016-meraki-mr32.dts
- lacks phy-mode

Verdict: opt into DSA workarounds.

bcm_sf2
~~~~~~~

compatible strings:
- brcm,bcm4908-switch
- brcm,bcm7445-switch-v4.0
- brcm,bcm7278-switch-v4.0
- brcm,bcm7278-switch-v4.8

A single occurrence in mainline
(arch/arm64/boot/dts/broadcom/bcm4908/bcm4908.dtsi), part of a SoC
dtsi, valid description. Florian Fainelli explains that most of the
bcm_sf2 device trees lack a full description for the internal IMP
ports.

Verdict: opt the BCM4908 into strict DT bindings, and opt the rest
into the workarounds. Note that even though BCM4908 has strict DT
bindings, it still does not register with phylink on the IMP port
due to it implementing ->adjust_link().

hellcreek
~~~~~~~~~

compatible strings:
- hirschmann,hellcreek-de1soc-r1

No occurrence in mainline device trees. Kurt Kanzenbach explains
that the downstream device trees lacked phy-mode and fixed link, and
needed work, but were fixed in the meantime.

Verdict: opt into strict DT bindings and out of workarounds.

lan9303
~~~~~~~

compatible strings:
- smsc,lan9303-mdio
- smsc,lan9303-i2c

1 occurrence in mainline device trees:
arch/arm/boot/dts/imx53-kp-hsc.dts
- no phy-mode, no fixed-link

Verdict: opt out of strict DT bindings and into workarounds.

lantiq_gswip
~~~~~~~~~~~~

compatible strings:
- lantiq,xrx200-gswip
- lantiq,xrx300-gswip
- lantiq,xrx330-gswip

No occurrences in mainline device trees. Martin Blumenstingl
confirms that the downstream OpenWrt device trees lack a proper
fixed-link and need work, and that the incomplete description can
even be seen in the example from
Documentation/devicetree/bindings/net/dsa/lantiq-gswip.txt.

Verdict: opt out of strict DT bindings and into workarounds.

microchip ksz
~~~~~~~~~~~~~

compatible strings:
- microchip,ksz8765
- microchip,ksz8794
- microchip,ksz8795
- microchip,ksz8863
- microchip,ksz8873
- microchip,ksz9477
- microchip,ksz9897
- microchip,ksz9893
- microchip,ksz9563
- microchip,ksz8563
- microchip,ksz9567
- microchip,lan9370
- microchip,lan9371
- microchip,lan9372
- microchip,lan9373
- microchip,lan9374

5 occurrences in mainline device trees, all descriptions are valid.
But we had a snafu for the ksz8795 and ksz9477 drivers where the
phy-mode property would be expected to be located directly under the
'switch' node rather than under a port OF node. It was fixed by
commit edecfa98f602 ("net: dsa: microchip: look for phy-mode in port
nodes"). The driver still has compatibility with the old DT blobs.
The lan937x support was added later than the above snafu was fixed,
and even though it has support for the broken DT blobs by virtue of
sharing a common probing function, I'll take it that its DT blobs
are correct.

Verdict: opt lan937x into strict DT bindings, and the others out.

mt7530
~~~~~~

compatible strings
- mediatek,mt7621
- mediatek,mt7530
- mediatek,mt7531

Multiple occurrences in mainline device trees, one is part of an SoC
dtsi (arch/mips/boot/dts/ralink/mt7621.dtsi), all descriptions are fine.

Verdict: opt into strict DT bindings and out of workarounds.

mv88e6060
~~~~~~~~~

compatible string:
- marvell,mv88e6060

no occurrences in mainline, nobody knows anybody who uses it.

Verdict: opt out of strict DT bindings and into workarounds.

mv88e6xxx
~~~~~~~~~

compatible strings:
- marvell,mv88e6085
- marvell,mv88e6190
- marvell,mv88e6250

Device trees that have incomplete descriptions of CPU or DSA ports:
arch/arm64/boot/dts/freescale/imx8mq-zii-ultra.dtsi
- lacks phy-mode
arch/arm64/boot/dts/marvell/cn9130-crb.dtsi
- lacks phy-mode and fixed-link
arch/arm/boot/dts/vf610-zii-ssmb-spu3.dts
- lacks phy-mode
arch/arm/boot/dts/kirkwood-mv88f6281gtw-ge.dts
- lacks phy-mode
arch/arm/boot/dts/vf610-zii-spb4.dts
- lacks phy-mode
arch/arm/boot/dts/vf610-zii-cfu1.dts
- lacks phy-mode
arch/arm/boot/dts/vf610-zii-dev-rev-c.dts
- lacks phy-mode on CPU port, fixed-link on DSA ports
arch/arm/boot/dts/vf610-zii-dev-rev-b.dts
- lacks phy-mode on CPU port
arch/arm/boot/dts/armada-381-netgear-gs110emx.dts
- lacks phy-mode
arch/arm/boot/dts/vf610-zii-scu4-aib.dts
- lacks fixed-link on xgmii DSA ports and/or in-band-status on
2500base-x DSA ports, and phy-mode on CPU port
arch/arm/boot/dts/imx6qdl-gw5904.dtsi
- lacks phy-mode and fixed-link
arch/arm/boot/dts/armada-385-clearfog-gtr-l8.dts
- lacks phy-mode and fixed-link
arch/arm/boot/dts/vf610-zii-ssmb-dtu.dts
- lacks phy-mode
arch/arm/boot/dts/kirkwood-dir665.dts
- lacks phy-mode
arch/arm/boot/dts/kirkwood-rd88f6281.dtsi
- lacks phy-mode
arch/arm/boot/dts/orion5x-netgear-wnr854t.dts
- lacks phy-mode and fixed-link
arch/arm/boot/dts/armada-388-clearfog.dts
- lacks phy-mode
arch/arm/boot/dts/armada-xp-linksys-mamba.dts
- lacks phy-mode
arch/arm/boot/dts/armada-385-linksys.dtsi
- lacks phy-mode
arch/arm/boot/dts/imx6q-b450v3.dts
arch/arm/boot/dts/imx6q-b850v3.dts
- has a phy-handle but not a phy-mode?
arch/arm/boot/dts/armada-370-rd.dts
- lacks phy-mode
arch/arm/boot/dts/kirkwood-linksys-viper.dts
- lacks phy-mode
arch/arm/boot/dts/imx51-zii-rdu1.dts
- lacks phy-mode
arch/arm/boot/dts/imx51-zii-scu2-mezz.dts
- lacks phy-mode
arch/arm/boot/dts/imx6qdl-zii-rdu2.dtsi
- lacks phy-mode
arch/arm/boot/dts/armada-385-clearfog-gtr-s4.dts
- lacks phy-mode and fixed-link

Verdict: opt out of strict DT bindings and into workarounds.

ocelot
~~~~~~

compatible strings:
- mscc,vsc9953-switch
- felix (arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi) is a PCI
device, has no compatible string

2 occurrences in mainline, both are part of SoC dtsi and complete.

Verdict: opt into strict DT bindings and out of workarounds.

qca8k
~~~~~

compatible strings:
- qca,qca8327
- qca,qca8328
- qca,qca8334
- qca,qca8337

5 occurrences in mainline device trees, none of the descriptions are
problematic.

Verdict: opt into strict DT bindings and out of workarounds.

realtek
~~~~~~~

compatible strings:
- realtek,rtl8366rb
- realtek,rtl8365mb

2 occurrences in mainline, both descriptions are fine, additionally
rtl8365mb.c has a comment "The device tree firmware should also
specify the link partner of the extension port - either via a
fixed-link or other phy-handle."

Verdict: opt into strict DT bindings and out of workarounds.

rzn1_a5psw
~~~~~~~~~~

compatible strings:
- renesas,rzn1-a5psw

One single occurrence, part of SoC dtsi
(arch/arm/boot/dts/r9a06g032.dtsi), description is fine.

Verdict: opt into strict DT bindings and out of workarounds.

sja1105
~~~~~~~

Driver already validates its port OF nodes in
sja1105_parse_ports_node().

Verdict: opt into strict DT bindings and out of workarounds.

vsc73xx
~~~~~~~

compatible strings:
- vitesse,vsc7385
- vitesse,vsc7388
- vitesse,vsc7395
- vitesse,vsc7398

2 occurrences in mainline device trees, both descriptions are fine.

Verdict: opt into strict DT bindings and out of workarounds.

xrs700x
~~~~~~~

compatible strings:
- arrow,xrs7003e
- arrow,xrs7003f
- arrow,xrs7004e
- arrow,xrs7004f

no occurrences in mainline, we don't know.

Verdict: opt out of strict DT bindings and into workarounds.

Because there is a pattern where newly added switches reuse existing
drivers more often than introducing new ones, I've opted for deciding
who gets to opt into the workaround based on an OF compatible match
table in the DSA core. The alternative would have been to add another
boolean property to struct dsa_switch, like configure_vlan_while_not_filtering.
But this avoids situations where sometimes driver maintainers obfuscate
what goes on by sharing a common probing function, and therefore making
new switches inherit old quirks.

Side note, we also warn about missing properties for drivers that rely
on the workaround. This isn't an indication that we'll break
compatibility with those DT blobs any time soon, but is rather done to
raise awareness about the change, for future DT blob authors.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Acked-by: Alvin Šipraga <alsi@bang-olufsen.dk> # realtek
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: rename dsa_port_link_{,un}register_of

There is a subset of functions that applies only to shared (DSA and CPU)
ports, yet this is difficult to comprehend by looking at their code alone.
These are dsa_port_link_register_of(), dsa_port_link_unregister_of(),
and the functions that only these 2 call.

Rename this class of functions to dsa_shared_port_* to make this fact
more evident, even if this goes against the apparent convention that
function names in port.c must start with dsa_port_.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: don't warn in dsa_port_set_state_now() when driver doesn't support it

ds->ops->port_stp_state_set() is, like most DSA methods, optional, and
if absent, the port is supposed to remain in the forwarding state (as
standalone). Such is the case with the mv88e6060 driver, which does not
offload the bridge layer. DSA warns that the STP state can't be changed
to FORWARDING as part of dsa_port_enable_rt(), when in fact it should not.

The error message is also not up to modern standards, so take the
opportunity to make it more descriptive.

Fixes: fd3645413197 ("net: dsa: change scope of STP state setter")
Reported-by: Sergei Antonov <saproj@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Sergei Antonov <saproj@gmail.com>
Link: https://lore.kernel.org/r/20220816201445.1809483-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: fix NULL pointer dereference in dsa_port_reset_vlan_filtering

The "ds" iterator variable used in dsa_port_reset_vlan_filtering() ->
dsa_switch_for_each_port() overwrites the "dp" received as argument,
which is later used to call dsa_port_vlan_filtering() proper.

As a result, switches which do enter that code path (the ones with
vlan_filtering_is_global=true) will dereference an invalid dp in
dsa_port_reset_vlan_filtering() after leaving a VLAN-aware bridge.

Use a dedicated "other_dp" iterator variable to avoid this from
happening.

Fixes: d0004a020bb5 ("net: dsa: remove the "dsa_to_port in a loop" antipattern from the core")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: fix dsa_port_vlan_filtering when global

The blamed refactoring commit changed a "port" iterator with "other_dp",
but still looked at the slave_dev of the dp outside the loop, instead of
other_dp->slave from the loop.

As a result, dsa_port_vlan_filtering() would not call
dsa_slave_manage_vlan_filtering() except for the port in cause, and not
for all switch ports as expected.

Fixes: d0004a020bb5 ("net: dsa: remove the "dsa_to_port in a loop" antipattern from the core")
Reported-by: Lucian Banu <Lucian.Banu@westermo.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: felix: manage host flooding using a specific driver callback

At the time - commit 7569459a52c9 ("net: dsa: manage flooding on the CPU
ports") - not introducing a dedicated switch callback for host flooding
made sense, because for the only user, the felix driver, there was
nothing different to do for the CPU port than set the flood flags on the
CPU port just like on any other bridge port.

There are 2 reasons why this approach is not good enough, however.

(1) Other drivers, like sja1105, support configuring flooding as a
function of {ingress port, egress port}, whereas the DSA
->port_bridge_flags() function only operates on an egress port.
So with that driver we'd have useless host flooding from user ports
which don't need it.

(2) Even with the felix driver, support for multiple CPU ports makes it
difficult to piggyback on ->port_bridge_flags(). The way in which
the felix driver is going to support host-filtered addresses with
multiple CPU ports is that it will direct these addresses towards
both CPU ports (in a sort of multicast fashion), then restrict the
forwarding to only one of the two using the forwarding masks.
Consequently, flooding will also be enabled towards both CPU ports.
However, ->port_bridge_flags() gets passed the index of a single CPU
port, and that leaves the flood settings out of sync between the 2
CPU ports.

This is to say, it's better to have a specific driver method for host
flooding, which takes the user port as argument. This solves problem (1)
by allowing the driver to do different things for different user ports,
and problem (2) by abstracting the operation and letting the driver do
whatever, rather than explicitly making the DSA core point to the CPU
port it thinks needs to be touched.

This new method also creates a problem, which is that cross-chip setups
are not handled. However I don't have hardware right now where I can
test what is the proper thing to do, and there isn't hardware compatible
with multi-switch trees that supports host flooding. So it remains a
problem to be tackled in the future.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: don't emit targeted cross-chip notifiers for MTU change

A cross-chip notifier with "targeted_match=true" is one that matches
only the local port of the switch that emitted it. In other words,
passing through the cross-chip notifier layer serves no purpose.

Eliminate this concept by calling directly ds->ops->port_change_mtu
instead of emitting a targeted cross-chip notifier. This leaves the
DSA_NOTIFIER_MTU event being emitted only for MTU updates on the CPU
port, which need to be reflected also across all DSA links.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: make cross-chip notifiers more efficient for host events

To determine whether a given port should react to the port targeted by
the notifier, dsa_port_host_vlan_match() and dsa_port_host_address_match()
look at the positioning of the switch port currently executing the
notifier relative to the switch port for which the notifier was emitted.

To maintain stylistic compatibility with the other match functions from
switch.c, the host address and host VLAN match functions take the
notifier information about targeted port, switch and tree indices as
argument. However, these functions only use that information to retrieve
the struct dsa_port *targeted_dp, which is an invariant for the outer
loop that calls them. So it makes more sense to calculate the targeted
dp only once, and pass it to them as argument.

But furthermore, the targeted dp is actually known at the time the call
to dsa_port_notify() is made. It is just that we decide to only save the
indices of the port, switch and tree in the notifier structure, just to
retrace our steps and find the dp again using dsa_switch_find() and
dsa_to_port().

But both the above functions are relatively expensive, since they need
to iterate through lists. It appears more straightforward to make all
notifiers just pass the targeted dp inside their info structure, and
have the code that needs the indices to look at info->dp->index instead
of info->port, or info->dp->ds->index instead of info->sw_index, or
info->dp->ds->dst->index instead of info->tree_index.

For the sake of consistency, all cross-chip notifiers are converted to
pass the "dp" directly.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move reset of VLAN filtering to dsa_port_switchdev_unsync_attrs

In dsa_port_switchdev_unsync_attrs() there is a comment that resetting
the VLAN filtering isn't done where it is expected. And since commit
108dc8741c20 ("net: dsa: Avoid cross-chip syncing of VLAN filtering"),
there is no reason to handle this in switch.c either.

Therefore, move the logic to port.c, and adapt it slightly to the data
structures and naming conventions from there.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: flush switchdev workqueue on bridge join error path

There is a race between switchdev_bridge_port_offload() and the
dsa_port_switchdev_sync_attrs() call right below it.

When switchdev_bridge_port_offload() finishes, FDB entries have been
replayed by the bridge, but are scheduled for deferred execution later.

However dsa_port_switchdev_sync_attrs -> dsa_port_can_apply_vlan_filtering()
may impose restrictions on the vlan_filtering attribute and refuse
offloading.

When this happens, the delayed FDB entries will dereference dp->bridge,
which is a NULL pointer because we have stopped the process of
offloading this bridge.

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Workqueue: dsa_ordered dsa_slave_switchdev_event_work
pc : dsa_port_bridge_host_fdb_del+0x64/0x100
lr : dsa_slave_switchdev_event_work+0x130/0x1bc
Call trace:
dsa_port_bridge_host_fdb_del+0x64/0x100
dsa_slave_switchdev_event_work+0x130/0x1bc
process_one_work+0x294/0x670
worker_thread+0x80/0x460
---[ end trace 0000000000000000 ]---
Error: dsa_core: Must first remove VLAN uppers having VIDs also present in bridge.

Fix the bug by doing what we do on the normal bridge leave path as well,
which is to wait until the deferred FDB entries complete executing, then
exit.

The placement of dsa_flush_workqueue() after switchdev_bridge_port_unoffload()
guarantees that both the FDB additions and deletions on rollback are waited for.

Fixes: d7d0d423dbaa ("net: dsa: flush switchdev workqueue when leaving the bridge")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220507134550.1849834-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: Add missing of_node_put() in dsa_port_link_register_of

The device_node pointer is returned by of_parse_phandle() with refcount
incremented. We should use of_node_put() on it when done.
of_node_put() will check for NULL value.

Fixes: a20f997010c4 ("net: dsa: Don't instantiate phylink for CPU/DSA ports unless needed")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Handle MST state changes

Add the usual trampoline functionality from the generic DSA layer down
to the drivers for MST state changes.

When a state changes to disabled/blocking/listening, make sure to fast
age any dynamic entries in the affected VLANs (those controlled by the
MSTI in question).

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: Pass VLAN MSTI migration notifications to driver

Add the usual trampoline functionality from the generic DSA layer down
to the drivers for VLAN MSTI migrations.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: Validate hardware support for MST

When joining a bridge where MST is enabled, we validate that the
proper offloading support is in place, otherwise we fallback to
software bridging.

When then mode is changed on a bridge in which we are members, we
refuse the change if offloading is not supported.

At the moment we only check for configurable learning, but this will
be further restricted as we support more MST related switchdev events.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: install secondary unicast and multicast addresses as host FDB/MDB

In preparation of disabling flooding towards the CPU in standalone ports
mode, identify the addresses requested by upper interfaces and use the
new API for DSA FDB isolation to request the hardware driver to offload
these as FDB or MDB objects. The objects belong to the user port's
database, and are installed pointing towards the CPU port.

Because dev_uc_add()/dev_mc_add() is VLAN-unaware, we offload to the
port standalone database addresses with VID 0 (also VLAN-unaware).
So this excludes switches with global VLAN filtering from supporting
unicast filtering, because there, it is possible for a port of a switch
to join a VLAN-aware bridge, and this changes the VLAN awareness of
standalone ports, requiring VLAN-aware standalone host FDB entries.
For the same reason, hellcreek, which requires VLAN awareness in
standalone mode, is also exempted from unicast filtering.

We create "standalone" variants of dsa_port_host_fdb_add() and
dsa_port_host_mdb_add() (and the _del coresponding functions).

We also create a separate work item type for handling deferred
standalone host FDB/MDB entries compared to the switchdev one.
This is done for the purpose of clarity - the procedure for offloading a
bridge FDB entry is different than offloading a standalone one, and
the switchdev event work handles only FDBs anyway, not MDBs.
Deferral is needed for standalone entries because ndo_set_rx_mode runs
in atomic context. We could probably optimize things a little by first
queuing up all entries that need to be offloaded, and scheduling the
work item just once, but the data structures that we can pass through
__dev_uc_sync() and __dev_mc_sync() are limiting (there is nothing like
a void *priv), so we'd have to keep the list of queued events somewhere
in struct dsa_switch, and possibly a lock for it. Too complicated for
now.

Adding the address to the master is handled by dev_uc_sync(), adding it
to the hardware is handled by __dev_uc_sync(). So this is the reason why
dsa_port_standalone_host_fdb_add() does not call dev_uc_add(). Not that
it had the rtnl_mutex anyway - ndo_set_rx_mode has it, but is atomic.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: rename the host FDB and MDB methods to contain the "bridge" namespace

We are preparing to add API in port.c that adds FDB and MDB entries that
correspond to the port's standalone database. Rename the existing
methods to make it clear that the FDB and MDB entries offloaded come
from the bridge database.

Since the function names lengthen in dsa_slave_switchdev_event_work(),
we place "addr" and "vid" in temporary variables, to shorten those.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: pass extack to .port_bridge_join driver methods

As FDB isolation cannot be enforced between VLAN-aware bridges in lack
of hardware assistance like extra FID bits, it seems plausible that many
DSA switches cannot do it. Therefore, they need to reject configurations
with multiple VLAN-aware bridges from the two code paths that can
transition towards that state:

- joining a VLAN-aware bridge
- toggling VLAN awareness on an existing bridge

The .port_vlan_filtering method already propagates the netlink extack to
the driver, let's propagate it from .port_bridge_join too, to make sure
that the driver can use the same function for both.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: request drivers to perform FDB isolation

For DSA, to encourage drivers to perform FDB isolation simply means to
track which bridge does each FDB and MDB entry belong to. It then
becomes the driver responsibility to use something that makes the FDB
entry from one bridge not match the FDB lookup of ports from other
bridges.

The top-level functions where the bridge is determined are:
- dsa_port_fdb_{add,del}
- dsa_port_host_fdb_{add,del}
- dsa_port_mdb_{add,del}
- dsa_port_host_mdb_{add,del}

aka the pre-crosschip-notifier functions.

Changing the API to pass a reference to a bridge is not superfluous, and
looking at the passed bridge argument is not the same as having the
driver look at dsa_to_port(ds, port)->bridge from the ->port_fdb_add()
method.

DSA installs FDB and MDB entries on shared (CPU and DSA) ports as well,
and those do not have any dp->bridge information to retrieve, because
they are not in any bridge - they are merely the pipes that serve the
user ports that are in one or multiple bridges.

The struct dsa_bridge associated with each FDB/MDB entry is encapsulated
in a larger "struct dsa_db" database. Although only databases associated
to bridges are notified for now, this API will be the starting point for
implementing IFF_UNICAST_FLT in DSA. There, the idea is to install FDB
entries on the CPU port which belong to the corresponding user port's
port database. These are supposed to match only when the port is
standalone.

It is better to introduce the API in its expected final form than to
introduce it for bridges first, then to have to change drivers which may
have made one or more assumptions.

Drivers can use the provided bridge.num, but they can also use a
different numbering scheme that is more convenient.

DSA must perform refcounting on the CPU and DSA ports by also taking
into account the bridge number. So if two bridges request the same local
address, DSA must notify the driver twice, once for each bridge.

In fact, if the driver supports FDB isolation, DSA must perform
refcounting per bridge, but if the driver doesn't, DSA must refcount
host addresses across all bridges, otherwise it would be telling the
driver to delete an FDB entry for a bridge and the driver would delete
it for all bridges. So introduce a bool fdb_isolation in drivers which
would make all bridge databases passed to the cross-chip notifier have
the same number (0). This makes dsa_mac_addr_find() -> dsa_db_equal()
say that all bridge databases are the same database - which is
essentially the legacy behavior.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: support FDB events on offloaded LAG interfaces

This change introduces support for installing static FDB entries towards
a bridge port that is a LAG of multiple DSA switch ports, as well as
support for filtering towards the CPU local FDB entries emitted for LAG
interfaces that are bridge ports.

Conceptually, host addresses on LAG ports are identical to what we do
for plain bridge ports. Whereas FDB entries _towards_ a LAG can't simply
be replicated towards all member ports like we do for multicast, or VLAN.
Instead we need new driver API. Hardware usually considers a LAG to be a
"logical port", and sets the entire LAG as the forwarding destination.
The physical egress port selection within the LAG is made by hashing
policy, as usual.

To represent the logical port corresponding to the LAG, we pass by value
a copy of the dsa_lag structure to all switches in the tree that have at
least one port in that LAG.

To illustrate why a refcounted list of FDB entries is needed in struct
dsa_lag, it is enough to say that:
- a LAG may be a bridge port and may therefore receive FDB events even
while it isn't yet offloaded by any DSA interface
- DSA interfaces may be removed from a LAG while that is a bridge port;
we don't want FDB entries lingering around, but we don't want to
remove entries that are still in use, either

For all the cases below to work, the idea is to always keep an FDB entry
on a LAG with a reference count equal to the DSA member ports. So:
- if a port joins a LAG, it requests the bridge to replay the FDB, and
the FDB entries get created, or their refcount gets bumped by one
- if a port leaves a LAG, the FDB replay deletes or decrements refcount
by one
- if an FDB is installed towards a LAG with ports already present, that
entry is created (if it doesn't exist) and its refcount is bumped by
the amount of ports already present in the LAG

echo "Adding FDB entry to bond with existing ports"
ip link del bond0
ip link add bond0 type bond mode 802.3ad
ip link set swp1 down && ip link set swp1 master bond0 && ip link set swp1 up
ip link set swp2 down && ip link set swp2 master bond0 && ip link set swp2 up
ip link del br0
ip link add br0 type bridge
ip link set bond0 master br0
bridge fdb add dev bond0 00:01:02:03:04:05 master static

ip link del br0
ip link del bond0

echo "Adding FDB entry to empty bond"
ip link del bond0
ip link add bond0 type bond mode 802.3ad
ip link del br0
ip link add br0 type bridge
ip link set bond0 master br0
bridge fdb add dev bond0 00:01:02:03:04:05 master static
ip link set swp1 down && ip link set swp1 master bond0 && ip link set swp1 up
ip link set swp2 down && ip link set swp2 master bond0 && ip link set swp2 up

ip link del br0
ip link del bond0

echo "Adding FDB entry to empty bond, then removing ports one by one"
ip link del bond0
ip link add bond0 type bond mode 802.3ad
ip link del br0
ip link add br0 type bridge
ip link set bond0 master br0
bridge fdb add dev bond0 00:01:02:03:04:05 master static
ip link set swp1 down && ip link set swp1 master bond0 && ip link set swp1 up
ip link set swp2 down && ip link set swp2 master bond0 && ip link set swp2 up

ip link set swp1 nomaster
ip link set swp2 nomaster
ip link del br0
ip link del bond0

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: create a dsa_lag structure

The main purpose of this change is to create a data structure for a LAG
as seen by DSA. This is similar to what we have for bridging - we pass a
copy of this structure by value to ->port_lag_join and ->port_lag_leave.
For now we keep the lag_dev, id and a reference count in it. Future
patches will add a list of FDB entries for the LAG (these also need to
be refcounted to work properly).

The LAG structure is created using dsa_port_lag_create() and destroyed
using dsa_port_lag_destroy(), just like we have for bridging.

Because now, the dsa_lag itself is refcounted, we can simplify
dsa_lag_map() and dsa_lag_unmap(). These functions need to keep a LAG in
the dst->lags array only as long as at least one port uses it. The
refcounting logic inside those functions can be removed now - they are
called only when we should perform the operation.

dsa_lag_dev() is renamed to dsa_lag_by_id() and now returns the dsa_lag
structure instead of the lag_dev net_device.

dsa_lag_foreach_port() now takes the dsa_lag structure as argument.

dst->lags holds an array of dsa_lag structures.

dsa_lag_map() now also saves the dsa_lag->id value, so that linear
walking of dst->lags in drivers using dsa_lag_id() is no longer
necessary. They can just look at lag.id.

dsa_port_lag_id_get() is a helper, similar to dsa_port_bridge_num_get(),
which can be used by drivers to get the LAG ID assigned by DSA to a
given port.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: rename references to "lag" as "lag_dev"

In preparation of converting struct net_device *dp->lag_dev into a
struct dsa_lag *dp->lag, we need to rename, for consistency purposes,
all occurrences of the "lag" variable in the DSA core to "lag_dev".

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: Include BR_PORT_LOCKED in the list of synced brport flags

Ensures that the DSA switch driver gets notified of changes to the
BR_PORT_LOCKED flag as well, for the case when a DSA port joins or
leaves a LAG that is a bridge port.

Signed-off-by: Hans Schultz <schultz.hans+netdev@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: phy: phylink: fix DSA mac_select_pcs() introduction

Vladimir Oltean reports that probing on DSA drivers that aren't yet
populating supported_interfaces now fails. Fix this by allowing
phylink to detect whether DSA actually provides an underlying
mac_select_pcs() implementation.

Reported-by: Vladimir Oltean <olteanv@gmail.com>
Fixes: bde018222c6b ("net: dsa: add support for phylink mac_select_pcs()")
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/E1nMCD6-00A0wC-FG@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: remove pcs_poll

With drivers converted over to using phylink PCS, there is no need for
the struct dsa_switch member "pcs_poll" to exist anymore - there is a
flag in the struct phylink_pcs which indicates whether this PCS needs
to be polled which supersedes this.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add support for phylink mac_select_pcs()

Add DSA support for the phylink mac_select_pcs() method so DSA drivers
can return provide phylink with the appropriate PCS for the PHY
interface mode.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: delete unused exported symbols for ethtool PHY stats

Introduced in commit cf963573039a ("net: dsa: Allow providing PHY
statistics from CPU port"), it appears these were never used.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220216193726.2926320-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: add explicit support for host bridge VLANs

Currently, DSA programs VLANs on shared (DSA and CPU) ports each time it
does so on user ports. This is good for basic functionality but has
several limitations:

- the VLAN group which must reach the CPU may be radically different
from the VLAN group that must be autonomously forwarded by the switch.
In other words, the admin may want to isolate noisy stations and avoid
traffic from them going to the control processor of the switch, where
it would just waste useless cycles. The bridge already supports
independent control of VLAN groups on bridge ports and on the bridge
itself, and when VLAN-aware, it will drop packets in software anyway
if their VID isn't added as a 'self' entry towards the bridge device.

- Replaying host FDB entries may depend, for some drivers like mv88e6xxx,
on replaying the host VLANs as well. The 2 VLAN groups are
approximately the same in most regular cases, but there are corner
cases when timing matters, and DSA's approximation of replicating
VLANs on shared ports simply does not work.

- If a user makes the bridge (implicitly the CPU port) join a VLAN by
accident, there is no way for the CPU port to isolate itself from that
noisy VLAN except by rebooting the system. This is because for each
VLAN added on a user port, DSA will add it on shared ports too, but
for each VLAN deletion on a user port, it will remain installed on
shared ports, since DSA has no good indication of whether the VLAN is
still in use or not.

Now that the bridge driver emits well-balanced SWITCHDEV_OBJ_ID_PORT_VLAN
addition and removal events, DSA has a simple and straightforward task
of separating the bridge port VLANs (these have an orig_dev which is a
DSA slave interface, or a LAG interface) from the host VLANs (these have
an orig_dev which is a bridge interface), and to keep a simple reference
count of each VID on each shared port.

Forwarding VLANs must be installed on the bridge ports and on all DSA
ports interconnecting them. We don't have a good view of the exact
topology, so we simply install forwarding VLANs on all DSA ports, which
is what has been done until now.

Host VLANs must be installed primarily on the dedicated CPU port of each
bridge port. More subtly, they must also be installed on upstream-facing
and downstream-facing DSA ports that are connecting the bridge ports and
the CPU. This ensures that the mv88e6xxx's problem (VID of host FDB
entry may be absent from VTU) is still addressed even if that switch is
in a cross-chip setup, and it has no local CPU port.

Therefore:
- user ports contain only bridge port (forwarding) VLANs, and no
refcounting is necessary
- DSA ports contain both forwarding and host VLANs. Refcounting is
necessary among these 2 types.
- CPU ports contain only host VLANs. Refcounting is also necessary.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: fix panic when removing unoffloaded port from bridge

If a bridged port is not offloaded to the hardware - either because the
underlying driver does not implement the port_bridge_{join,leave} ops,
or because the operation failed - then its dp->bridge pointer will be
NULL when dsa_port_bridge_leave() is called. Avoid dereferncing NULL.

This fixes the following splat when removing a port from a bridge:

Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000
Internal error: Oops: 96000004 [#1] PREEMPT_RT SMP
CPU: 3 PID: 1119 Comm: brctl Tainted: G O 5.17.0-rc4-rt4 #1
Call trace:
dsa_port_bridge_leave+0x8c/0x1e4
dsa_slave_changeupper+0x40/0x170
dsa_slave_netdevice_event+0x494/0x4d4
notifier_call_chain+0x80/0xe0
raw_notifier_call_chain+0x1c/0x24
call_netdevice_notifiers_info+0x5c/0xac
__netdev_upper_dev_unlink+0xa4/0x200
netdev_upper_dev_unlink+0x38/0x60
del_nbp+0x1b0/0x300
br_del_if+0x38/0x114
add_del_if+0x60/0xa0
br_ioctl_stub+0x128/0x2dc
br_ioctl_call+0x68/0xb0
dev_ifsioc+0x390/0x554
dev_ioctl+0x128/0x400
sock_do_ioctl+0xb4/0xf4
sock_ioctl+0x12c/0x4e0
__arm64_sys_ioctl+0xa8/0xf0
invoke_syscall+0x4c/0x110
el0_svc_common.constprop.0+0x48/0xf0
do_el0_svc+0x28/0x84
el0_svc+0x1c/0x50
el0t_64_sync_handler+0xa8/0xb0
el0t_64_sync+0x17c/0x180
Code: f9402f00 f0002261 f9401302 913cc021 (a9401404)
---[ end trace 0000000000000000 ]---

Fixes: d3eed0e57d5d ("net: dsa: keep the bridge_dev and bridge_num as part of the same structure")
Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220221203539.310690-1-alvin@pqrs.dk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: avoid call to __dev_set_promiscuity() while rtnl_mutex isn't held

If the DSA master doesn't support IFF_UNICAST_FLT, then the following
call path is possible:

dsa_slave_switchdev_event_work
-> dsa_port_host_fdb_add
-> dev_uc_add
-> __dev_set_rx_mode
-> __dev_set_promiscuity

Since the blamed commit, dsa_slave_switchdev_event_work() no longer
holds rtnl_lock(), which triggers the ASSERT_RTNL() from
__dev_set_promiscuity().

Taking rtnl_lock() around dev_uc_add() is impossible, because all the
code paths that call dsa_flush_workqueue() do so from contexts where the
rtnl_mutex is already held - so this would lead to an instant deadlock.

dev_uc_add() in itself doesn't require the rtnl_mutex for protection.
There is this comment in __dev_set_rx_mode() which assumes so:

/* Unicast addresses changes may only happen under the rtnl,
* therefore calling __dev_set_promiscuity here is safe.
*/

but it is from commit 4417da668c00 ("[NET]: dev: secondary unicast
address support") dated June 2007, and in the meantime, commit
f1f28aa3510d ("netdev: Add addr_list_lock to struct net_device."), dated
July 2008, has added &dev->addr_list_lock to protect this instead of the
global rtnl_mutex.

Nonetheless, __dev_set_promiscuity() does assume rtnl_mutex protection,
but it is the uncommon path of what we typically expect dev_uc_add()
to do. So since only the uncommon path requires rtnl_lock(), just check
ahead of time whether dev_uc_add() would result into a call to
__dev_set_promiscuity(), and handle that condition separately.

DSA already configures the master interface to be promiscuous if the
tagger requires this. We can extend this to also cover the case where
the master doesn't handle dev_uc_add() (doesn't support IFF_UNICAST_FLT),
and on the premise that we'd end up making it promiscuous during
operation anyway, either if a DSA slave has a non-inherited MAC address,
or if the bridge notifies local FDB entries for its own MAC address, the
address of a station learned on a foreign port, etc.

Fixes: 0faf890fc519 ("net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work")
Reported-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: remove cross-chip support for HSR

The cross-chip notifiers for HSR are bypass operations, meaning that
even though all switches in a tree are notified, only the switch
specified in the info structure is targeted.

We can eliminate the unnecessary complexity by deleting the cross-chip
notifier logic and calling the ds->ops straight from port.c.

Cc: George McCollister <george.mccollister@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: George McCollister <george.mccollister@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: remove cross-chip support for MRP

The cross-chip notifiers for MRP are bypass operations, meaning that
even though all switches in a tree are notified, only the switch
specified in the info structure is targeted.

We can eliminate the unnecessary complexity by deleting the cross-chip
notifier logic and calling the ds->ops straight from port.c.

Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: mark DSA phylink as legacy_pre_march2020

The majority of DSA drivers do not make use of the PCS support, and
thus operate in legacy mode. In order to preserve this behaviour in
future, we need to set the legacy_pre_march2020 flag so phylink knows
this may require the legacy calls.

There are some DSA drivers that do make use of PCS support, and these
will continue operating as before - legacy_pre_march2020 will not
prevent split-PCS support enabling the newer phylink behaviour.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: eliminate dsa_switch_ops :: port_bridge_tx_fwd_{,un}offload

We don't really need new switch API for these, and with new switches
which intend to add support for this feature, it will become cumbersome
to maintain.

The change consists in restructuring the two drivers that implement this
offload (sja1105 and mv88e6xxx) such that the offload is enabled and
disabled from the ->port_bridge_{join,leave} methods instead of the old
->port_bridge_tx_fwd_{,un}offload.

The only non-trivial change is that mv88e6xxx_map_virtual_bridge_to_pvt()
has been moved to avoid a forward declaration, and the
mv88e6xxx_reg_lock() calls from inside it have been removed, since
locking is now done from mv88e6xxx_port_bridge_{join,leave}.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: keep the bridge_dev and bridge_num as part of the same structure

The main desire behind this is to provide coherent bridge information to
the fast path without locking.

For example, right now we set dp->bridge_dev and dp->bridge_num from
separate code paths, it is theoretically possible for a packet
transmission to read these two port properties consecutively and find a
bridge number which does not correspond with the bridge device.

Another desire is to start passing more complex bridge information to
dsa_switch_ops functions. For example, with FDB isolation, it is
expected that drivers will need to be passed the bridge which requested
an FDB/MDB entry to be offloaded, and along with that bridge_dev, the
associated bridge_num should be passed too, in case the driver might
want to implement an isolation scheme based on that number.

We already pass the {bridge_dev, bridge_num} pair to the TX forwarding
offload switch API, however we'd like to remove that and squash it into
the basic bridge join/leave API. So that means we need to pass this
pair to the bridge join/leave API.

During dsa_port_bridge_leave, first we unset dp->bridge_dev, then we
call the driver's .port_bridge_leave with what used to be our
dp->bridge_dev, but provided as an argument.

When bridge_dev and bridge_num get folded into a single structure, we
need to preserve this behavior in dsa_port_bridge_leave: we need a copy
of what used to be in dp->bridge.

Switch drivers check bridge membership by comparing dp->bridge_dev with
the provided bridge_dev, but now, if we provide the struct dsa_bridge as
a pointer, they cannot keep comparing dp->bridge to the provided
pointer, since this only points to an on-stack copy. To make this
obvious and prevent driver writers from forgetting and doing stupid
things, in this new API, the struct dsa_bridge is provided as a full
structure (not very large, contains an int and a pointer) instead of a
pointer. An explicit comparison function needs to be used to determine
bridge membership: dsa_port_offloads_bridge().

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: hide dp->bridge_dev and dp->bridge_num in the core behind helpers

The location of the bridge device pointer and number is going to change.
It is not going to be kept individually per port, but in a common
structure allocated dynamically and which will have lockdep validation.

Create helpers to access these elements so that we have a migration path
to the new organization.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: assign a bridge number even without TX forwarding offload

The service where DSA assigns a unique bridge number for each forwarding
domain is useful even for drivers which do not implement the TX
forwarding offload feature.

For example, drivers might use the dp->bridge_num for FDB isolation.

So rename ds->num_fwd_offloading_bridges to ds->max_num_bridges, and
calculate a unique bridge_num for all drivers that set this value.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: make dp->bridge_num one-based

I have seen too many bugs already due to the fact that we must encode an
invalid dp->bridge_num as a negative value, because the natural tendency
is to check that invalid value using (!dp->bridge_num). Latest example
can be seen in commit 1bec0f05062c ("net: dsa: fix bridge_num not
getting cleared after ports leaving the bridge").

Convert the existing users to assume that dp->bridge_num == 0 is the
encoding for invalid, and valid bridge numbers start from 1.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: support use of phylink_generic_validate()

Support the use of phylink_generic_validate() when there is no
phylink_validate method given in the DSA switch operations and
mac_capabilities have been set in the phylink_config structure by the
DSA switch driver.

This gives DSA switch drivers the option to use this if they provide
the supported_interfaces and mac_capabilities, while still giving them
an option to override the default implementation if necessary.

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: replace phylink_get_interfaces() with phylink_get_caps()

Phylink needs slightly more information than phylink_get_interfaces()
allows us to get from the DSA drivers - we need the MAC capabilities.
Replace the phylink_get_interfaces() method with phylink_get_caps() to
allow DSA drivers to fill in the phylink_config MAC capabilities field
as well.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: consolidate phylink creation

The code in port.c and slave.c creating the phylink instance is very
similar - let's consolidate this into a single function.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: populate supported_interfaces member

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

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

Signed-off-by: Marek Behún <kabel@kernel.org>
[tweaked patch and description to add more complete support -- rmk]
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: flush switchdev workqueue when leaving the bridge

DSA is preparing to offer switch drivers an API through which they can
associate each FDB entry with a struct net_device *bridge_dev. This can
be used to perform FDB isolation (the FDB lookup performed on the
ingress of a standalone, or bridged port, should not find an FDB entry
that is present in the FDB of another bridge).

In preparation of that work, DSA needs to ensure that by the time we
call the switch .port_fdb_add and .port_fdb_del methods, the
dp->bridge_dev pointer is still valid, i.e. the port is still a bridge
port.

This is not guaranteed because the SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE API
requires drivers that must have sleepable context to handle those events
to schedule the deferred work themselves. DSA does this through the
dsa_owq.

It can happen that a port leaves a bridge, del_nbp() flushes the FDB on
that port, SWITCHDEV_FDB_DEL_TO_DEVICE is notified in atomic context,
DSA schedules its deferred work, but del_nbp() finishes unlinking the
bridge as a master from the port before DSA's deferred work is run.

Fundamentally, the port must not be unlinked from the bridge until all
FDB deletion deferred work items have been flushed. The bridge must wait
for the completion of these hardware accesses.

An attempt has been made to address this issue centrally in switchdev by
making SWITCHDEV_FDB_DEL_TO_DEVICE deferred (=> blocking) at the switchdev
level, which would offer implicit synchronization with del_nbp:

https://patchwork.kernel.org/project/netdevbpf/cover/20210820115746.3701811-1-vladimir.oltean@nxp.com/

but it seems that any attempt to modify switchdev's behavior and make
the events blocking there would introduce undesirable side effects in
other switchdev consumers.

The most undesirable behavior seems to be that
switchdev_deferred_process_work() takes the rtnl_mutex itself, which
would be worse off than having the rtnl_mutex taken individually from
drivers which is what we have now (except DSA which has removed that
lock since commit 0faf890fc519 ("net: dsa: drop rtnl_lock from
dsa_slave_switchdev_event_work")).

So to offer the needed guarantee to DSA switch drivers, I have come up
with a compromise solution that does not require switchdev rework:
we already have a hook at the last moment in time when the bridge is
still an upper of ours: the NETDEV_PRECHANGEUPPER handler. We can flush
the dsa_owq manually from there, which makes all FDB deletions
synchronous.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: remove gratuitous use of dsa_is_{user,dsa,cpu}_port

Find the occurrences of dsa_is_{user,dsa,cpu}_port where a struct
dsa_port *dp was already available in the function scope, and replace
them with the dsa_port_is_{user,dsa,cpu} equivalent function which uses
that dp directly and does not perform another hidden dsa_to_port().

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

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

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

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

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

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: don't advertise 'rx-vlan-filter' when not needed

There have been multiple independent reports about
dsa_slave_vlan_rx_add_vid being called (and consequently calling the
drivers' .port_vlan_add) when it isn't needed, and sometimes (not
always) causing problems in the process.

Case 1:
mv88e6xxx_port_vlan_prepare is stubborn and only accepts VLANs on
bridged ports. That is understandably so, because standalone mv88e6xxx
ports are VLAN-unaware, and VTU entries are said to be a scarce
resource.

Otherwise said, the following fails lamentably on mv88e6xxx:

ip link add br0 type bridge vlan_filtering 1
ip link set lan3 master br0
ip link add link lan10 name lan10.1 type vlan id 1
[485256.724147] mv88e6085 d0032004.mdio-mii:12: p10: hw VLAN 1 already used by port 3 in br0
RTNETLINK answers: Operation not supported

This has become a worse issue since commit 9b236d2a69da ("net: dsa:
Advertise the VLAN offload netdev ability only if switch supports it").
Up to that point, the driver was returning -EOPNOTSUPP and DSA was
reconverting that error to 0, making the 8021q upper think all is ok
(but obviously the error message was there even prior to this change).
After that change the -EOPNOTSUPP is propagated to vlan_vid_add, and it
is a hard error.

Case 2:
Ports that don't offload the Linux bridge (have a dp->bridge_dev = NULL
because they don't implement .port_bridge_{join,leave}). Understandably,
a standalone port should not offload VLANs either, it should remain VLAN
unaware and any VLAN should be a software VLAN (as long as the hardware
is not quirky, that is).

In fact, dsa_slave_port_obj_add does do the right thing and rejects
switchdev VLAN objects coming from the bridge when that bridge is not
offloaded:

case SWITCHDEV_OBJ_ID_PORT_VLAN:
if (!dsa_port_offloads_bridge_port(dp, obj->orig_dev))
return -EOPNOTSUPP;

err = dsa_slave_vlan_add(dev, obj, extack);

But it seems that the bridge is able to trick us. The __vlan_vid_add
from br_vlan.c has:

/* Try switchdev op first. In case it is not supported, fallback to
* 8021q add.
*/
err = br_switchdev_port_vlan_add(dev, v->vid, flags, extack);
if (err == -EOPNOTSUPP)
return vlan_vid_add(dev, br->vlan_proto, v->vid);

So it says "no, no, you need this VLAN in your life!". And we, naive as
we are, say "oh, this comes from the vlan_vid_add code path, it must be
an 8021q upper, sure, I'll take that". And we end up with that bridge
VLAN installed on our port anyway. But this time, it has the wrong flags:
if the bridge was trying to install VLAN 1 as a pvid/untagged VLAN,
failed via switchdev, retried via vlan_vid_add, we have this comment:

/* This API only allows programming tagged, non-PVID VIDs */

So what we do makes absolutely no sense.

Backtracing a bit, we see the common pattern. We allow the network stack
to think that our standalone ports are VLAN-aware, but they aren't, for
the vast majority of switches. The quirky ones should not dictate the
norm. The dsa_slave_vlan_rx_add_vid and dsa_slave_vlan_rx_kill_vid
methods exist for drivers that need the 'rx-vlan-filter: on' feature in
ethtool -k, which can be due to any of the following reasons:

1. vlan_filtering_is_global = true, and some ports are under a
VLAN-aware bridge while others are standalone, and the standalone
ports would otherwise drop VLAN-tagged traffic. This is described in
commit 061f6a505ac3 ("net: dsa: Add ndo_vlan_rx_{add, kill}_vid
implementation").

2. the ports that are under a VLAN-aware bridge should also set this
feature, for 8021q uppers having a VID not claimed by the bridge.
In this case, the driver will essentially not even know that the VID
is coming from the 8021q layer and not the bridge.

3. Hellcreek. This driver needs it because in standalone mode, it uses
unique VLANs per port to ensure separation. For separation of untagged
traffic, it uses different PVIDs for each port, and for separation of
VLAN-tagged traffic, it never accepts 8021q uppers with the same vid
on two ports.

If a driver does not fall under any of the above 3 categories, there is
no reason why it should advertise the 'rx-vlan-filter' feature, therefore
no reason why it should offload the VLANs added through vlan_vid_add.

This commit fixes the problem by removing the 'rx-vlan-filter' feature
from the slave devices when they operate in standalone mode, and when
they offload a VLAN-unaware bridge.

The way it works is that vlan_vid_add will now stop its processing here:

vlan_add_rx_filter_info:
if (!vlan_hw_filter_capable(dev, proto))
return 0;

So the VLAN will still be saved in the interface's VLAN RX filtering
list, but because it does not declare VLAN filtering in its features,
the 8021q module will return zero without committing that VLAN to
hardware.

This gives the drivers what they want, since it keeps the 8021q VLANs
away from the VLAN table until VLAN awareness is enabled (point at which
the ports are no longer standalone, hence in the mv88e6xxx case, the
check in mv88e6xxx_port_vlan_prepare passes).

Since the issue predates the existence of the hellcreek driver, case 3
will be dealt with in a separate patch.

The main change that this patch makes is to no longer set
NETIF_F_HW_VLAN_CTAG_FILTER unconditionally, but toggle it dynamically
(for most switches, never).

The second part of the patch addresses an issue that the first part
introduces: because the 'rx-vlan-filter' feature is now dynamically
toggled, and our .ndo_vlan_rx_add_vid does not get called when
'rx-vlan-filter' is off, we need to avoid bugs such as the following by
replaying the VLANs from 8021q uppers every time we enable VLAN
filtering:

ip link add link lan0 name lan0.100 type vlan id 100
ip addr add 192.168.100.1/24 dev lan0.100
ping 192.168.100.2 # should work
ip link add br0 type bridge vlan_filtering 0
ip link set lan0 master br0
ping 192.168.100.2 # should still work
ip link set br0 type bridge vlan_filtering 1
ping 192.168.100.2 # should still work but doesn't

As reported by Florian, some drivers look at ds->vlan_filtering in
their .port_vlan_add() implementation. So this patch also makes sure
that ds->vlan_filtering is committed before calling the driver. This is
the reason why it is first committed, then restored on the failure path.

Reported-by: Tobias Waldekranz <tobias@waldekranz.com>
Reported-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: don't call switchdev_bridge_port_unoffload for unoffloaded bridge ports

For ports that have a NULL dp->bridge_dev, dsa_port_to_bridge_port()
also returns NULL as expected.

Issue #1 is that we are performing a NULL pointer dereference on brport_dev.

Issue #2 is that these are ports on which switchdev_bridge_port_offload
has not been called, so we should not call switchdev_bridge_port_unoffload
on them either.

Both issues are addressed by checking against a NULL brport_dev in
dsa_port_pre_bridge_leave and exiting early.

Fixes: 2f5dc00f7a3e ("net: bridge: switchdev: let drivers inform which bridge ports are offloaded")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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>

net: dsa: tag_8021q: don't broadcast during setup/teardown

Currently, on my board with multiple sja1105 switches in disjoint trees
described in commit f66a6a69f97a ("net: dsa: permit cross-chip bridging
between all trees in the system"), rebooting the board triggers the
following benign warnings:

[ 12.345566] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 1088 deletion: -ENOENT
[ 12.353804] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 2112 deletion: -ENOENT
[ 12.362019] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 1089 deletion: -ENOENT
[ 12.370246] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 2113 deletion: -ENOENT
[ 12.378466] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 1090 deletion: -ENOENT
[ 12.386683] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 2114 deletion: -ENOENT

Basically switch 1 calls dsa_tag_8021q_unregister, and switch 1's TX and
RX VLANs cannot be found on switch 2's CPU port.

But why would switch 2 even attempt to delete switch 1's TX and RX
tag_8021q VLANs from its CPU port? Well, because we use dsa_broadcast,
and it is supposed that it had added those VLANs in the first place
(because in dsa_port_tag_8021q_vlan_match, all CPU ports match
regardless of their tree index or switch index).

The two trees probe asynchronously, and when switch 1 probed, it called
dsa_broadcast which did not notify the tree of switch 2, because that
didn't probe yet. But during unbind, switch 2's tree _is_ probed, so it
_is_ notified of the deletion.

Before jumping to introduce a synchronization mechanism between the
probing across disjoint switch trees, let's take a step back and see
whether we _need_ to do that in the first place.

The RX and TX VLANs of switch 1 would be needed on switch 2's CPU port
only if switch 1 and 2 were part of a cross-chip bridge. And
dsa_tag_8021q_bridge_join takes care precisely of that (but if probing
was synchronous, the bridge_join would just end up bumping the VLANs'
refcount, because they are already installed by the setup path).

Since by the time the ports are bridged, all DSA trees are already set
up, and we don't need the tag_8021q VLANs of one switch installed on the
other switches during probe time, the answer is that we don't need to
fix the synchronization issue.

So make the setup and teardown code paths call dsa_port_notify, which
notifies only the local tree, and the bridge code paths call
dsa_broadcast, which let the other trees know as well.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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>

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>

net: dsa: still fast-age ports joining a bridge if they can't configure learning

Commit 39f32101543b ("net: dsa: don't fast age standalone ports")
assumed that all standalone ports disable address learning, but if the
switch driver implements .port_fast_age but not .port_bridge_flags (like
ksz9477, ksz8795, lantiq_gswip, lan9303), then that might not actually
be true.

So whereas before, the bridge temporarily walking us through the
BLOCKING STP state meant that the standalone ports had a checkpoint to
flush their baggage and start fresh when they join a bridge, after that
commit they no longer do.

Restore the old behavior for these drivers by checking if the switch can
toggle address learning. If it can't, disregard the "do_fast_age"
argument and unconditionally perform fast ageing on STP state changes.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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>

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>

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>

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 5e38c15856e9 ("net: dsa: configure better brport flags when
ports leave the bridge"), DSA asks standalone ports to disable address
learning. Therefore, there can be no dynamic FDB entries on a standalone
port. Therefore, it does not make sense to flush dynamic FDB entries on
one.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: don't disable multicast flooding to the CPU even without an IGMP querier

Commit 08cc83cc7fd8 ("net: dsa: add support for BRIDGE_MROUTER
attribute") added an option for users to turn off multicast flooding
towards the CPU if they turn off the IGMP querier on a bridge which
already has enslaved ports (echo 0 > /sys/class/net/br0/bridge/multicast_router).

And commit a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags")
simply papered over that issue, because it moved the decision to flood
the CPU with multicast (or not) from the DSA core down to individual drivers,
instead of taking a more radical position then.

The truth is that disabling multicast flooding to the CPU is simply
something we are not prepared to do now, if at all. Some reasons:

- ICMP6 neighbor solicitation messages are unregistered multicast
packets as far as the bridge is concerned. So if we stop flooding
multicast, the outside world cannot ping the bridge device's IPv6
link-local address.

- There might be foreign interfaces bridged with our DSA switch ports
(sending a packet towards the host does not necessarily equal
termination, but maybe software forwarding). So if there is no one
interested in that multicast traffic in the local network stack, that
doesn't mean nobody is.

- PTP over L4 (IPv4, IPv6) is multicast, but is unregistered as far as
the bridge is concerned. This should reach the CPU port.

- The switch driver might not do FDB partitioning. And since we don't
even bother to do more fine-grained flood disabling (such as "disable
flooding _from_port_N_ towards the CPU port" as opposed to "disable
flooding _from_any_port_ towards the CPU port"), this breaks standalone
ports, or even multiple bridges where one has an IGMP querier and one
doesn't.

Reverting the logic makes all of the above work.

Fixes: a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags")
Fixes: 08cc83cc7fd8 ("net: dsa: add support for BRIDGE_MROUTER attribute")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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: 010e269f91be ("net: dsa: sync up switchdev objects and port attributes when joining the bridge")
Reported-by: DENG Qingfang <dqfext@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Revert "net: dsa: Allow drivers to filter packets they can decode source port from"

This reverts commit cc1939e4b3aaf534fb2f3706820012036825731c.

Currently 2 classes of DSA drivers are able to send/receive packets
directly through the DSA master:
- drivers with DSA_TAG_PROTO_NONE
- sja1105

Now that sja1105 has gained the ability to perform traffic termination
even under the tricky case (VLAN-aware bridge), and that is much more
functional (we can perform VLAN-aware bridging with foreign interfaces),
there is no reason to keep this code in the receive path of the network
core. So delete it.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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>

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>

net: bridge: move the switchdev object replay helpers to "push" mode

Starting with commit 4f2673b3a2b6 ("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 0d2cfbd41c4a ("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
2c4eca3ef716 ("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
4f2673b3a2b6 ("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>

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>

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>

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>

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>

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>

net: dsa: introduce a separate cross-chip notifier type for host MDBs

Commit abd49535c380 ("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>

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>

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>

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>

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>

net: dsa: fix bridge support for drivers without port_bridge_flags callback

Starting with patch:
a8b659e7ff75 ("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: 5961d6a12c13 ("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>

net: dsa: sync up switchdev objects and port attributes when joining the bridge

If we join an already-created bridge port, such as a bond master
interface, then we can miss the initial switchdev notifications emitted
by the bridge for this port, while it wasn't offloaded by anybody.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: inherit the actual bridge port flags at join time

DSA currently assumes that the bridge port starts off with this
constellation of bridge port flags:

- learning on
- unicast flooding on
- multicast flooding on
- broadcast flooding on

just by virtue of code copy-pasta from the bridge layer (new_nbp).
This was a simple enough strategy thus far, because the 'bridge join'
moment always coincided with the 'bridge port creation' moment.

But with sandwiched interfaces, such as:

br0
|
bond0
|
swp0

it may happen that the user has had time to change the bridge port flags
of bond0 before enslaving swp0 to it. In that case, swp0 will falsely
assume that the bridge port flags are those determined by new_nbp, when
in fact this can happen:

ip link add br0 type bridge
ip link add bond0 type bond
ip link set bond0 master br0
ip link set bond0 type bridge_slave learning off
ip link set swp0 master br0

Now swp0 has learning enabled, bond0 has learning disabled. Not nice.

Fix this by "dumpster diving" through the actual bridge port flags with
br_port_flag_is_set, at bridge join time.

We use this opportunity to split dsa_port_change_brport_flags into two
distinct functions called dsa_port_inherit_brport_flags and
dsa_port_clear_brport_flags, now that the implementation for the two
cases is no longer similar. This patch also creates two functions called
dsa_port_switchdev_sync and dsa_port_switchdev_unsync which collect what
we have so far, even if that's asymmetrical. More is going to be added
in the next patch.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: pass extack to dsa_port_{bridge,lag}_join

This is a pretty noisy change that was broken out of the larger change
for replaying switchdev attributes and objects at bridge join time,
which is when these extack objects are actually used.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: call dsa_port_bridge_join when joining a LAG that is already in a bridge

DSA can properly detect and offload this sequence of operations:

ip link add br0 type bridge
ip link add bond0 type bond
ip link set swp0 master bond0
ip link set bond0 master br0

But not this one:

ip link add br0 type bridge
ip link add bond0 type bond
ip link set bond0 master br0
ip link set swp0 master bond0

Actually the second one is more complicated, due to the elapsed time
between the enslavement of bond0 and the offloading of it via swp0, a
lot of things could have happened to the bond0 bridge port in terms of
switchdev objects (host MDBs, VLANs, altered STP state etc). So this is
a bit of a can of worms, and making sure that the DSA port's state is in
sync with this already existing bridge port is handled in the next
patches.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add MRP support

Add support for offloading MRP in HW. Currently implement the switchdev
calls 'SWITCHDEV_OBJ_ID_MRP', 'SWITCHDEV_OBJ_ID_RING_ROLE_MRP',
to allow to create MRP instances and to set the role of these instances.

Add DSA_NOTIFIER_MRP_ADD/DEL and DSA_NOTIFIER_MRP_ADD/DEL_RING_ROLE
which calls to .port_mrp_add/del and .port_mrp_add/del_ring_role in the
DSA driver for the switch.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: propagate extack to .port_vlan_filtering

Some drivers can't dynamically change the VLAN filtering option, or
impose some restrictions, it would be nice to propagate this info
through netlink instead of printing it to a kernel log that might never
be read. Also netlink extack includes the module that emitted the
message, which means that it's easier to figure out which ones are
driver-generated errors as opposed to command misuse.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: propagate extack to .port_vlan_add

Allow drivers to communicate their restrictions to user space directly,
instead of printing to the kernel log. Where the conversion would have
been lossy and things like VLAN ID could no longer be conveyed (due to
the lack of support for printf format specifier in netlink extack), I
chose to keep the messages in full form to the kernel log only, and
leave it up to individual driver maintainers to move more messages to
extack.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: act as passthrough for bridge port flags

There are multiple ways in which a PORT_BRIDGE_FLAGS attribute can be
expressed by the bridge through switchdev, and not all of them can be
emulated by DSA mid-layer API at the same time.

One possible configuration is when the bridge offloads the port flags
using a mask that has a single bit set - therefore only one feature
should change. However, DSA currently groups together unicast and
multicast flooding in the .port_egress_floods method, which limits our
options when we try to add support for turning off broadcast flooding:
do we extend .port_egress_floods with a third parameter which b53 and
mv88e6xxx will ignore? But that means that the DSA layer, which
currently implements the PRE_BRIDGE_FLAGS attribute all by itself, will
see that .port_egress_floods is implemented, and will report that all 3
types of flooding are supported - not necessarily true.

Another configuration is when the user specifies more than one flag at
the same time, in the same netlink message. If we were to create one
individual function per offloadable bridge port flag, we would limit the
expressiveness of the switch driver of refusing certain combinations of
flag values. For example, a switch may not have an explicit knob for
flooding of unknown multicast, just for flooding in general. In that
case, the only correct thing to do is to allow changes to BR_FLOOD and
BR_MCAST_FLOOD in tandem, and never allow mismatched values. But having
a separate .port_set_unicast_flood and .port_set_multicast_flood would
not allow the driver to possibly reject that.

Also, DSA doesn't consider it necessary to inform the driver that a
SWITCHDEV_ATTR_ID_BRIDGE_MROUTER attribute was offloaded, because it
just calls .port_egress_floods for the CPU port. When we'll add support
for the plain SWITCHDEV_ATTR_ID_PORT_MROUTER, that will become a real
problem because the flood settings will need to be held statefully in
the DSA middle layer, otherwise changing the mrouter port attribute will
impact the flooding attribute. And that's _assuming_ that the underlying
hardware doesn't have anything else to do when a multicast router
attaches to a port than flood unknown traffic to it. If it does, there
will need to be a dedicated .port_set_mrouter anyway.

So we need to let the DSA drivers see the exact form that the bridge
passes this switchdev attribute in, otherwise we are standing in the
way. Therefore we also need to use this form of language when
communicating to the driver that it needs to configure its initial
(before bridge join) and final (after bridge leave) port flags.

The b53 and mv88e6xxx drivers are converted to the passthrough API and
their implementation of .port_egress_floods is split into two: a
function that configures unicast flooding and another for multicast.
The mv88e6xxx implementation is quite hairy, and it turns out that
the implementations of unknown unicast flooding are actually the same
for 6185 and for 6352:

behind the confusing names actually lie two individual bits:
NO_UNKNOWN_MC -> FLOOD_UC = 0x4 = BIT(2)
NO_UNKNOWN_UC -> FLOOD_MC = 0x8 = BIT(3)

so there was no reason to entangle them in the first place.

Whereas the 6185 writes to MV88E6185_PORT_CTL0_FORWARD_UNKNOWN of
PORT_CTL0, which has the exact same bit index. I have left the
implementations separate though, for the only reason that the names are
different enough to confuse me, since I am not able to double-check with
a user manual. The multicast flooding setting for 6185 is in a different
register than for 6352 though.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: switchdev: pass flags and mask to both {PRE_,}BRIDGE_FLAGS attributes

This switchdev attribute offers a counterproductive API for a driver
writer, because although br_switchdev_set_port_flag gets passed a
"flags" and a "mask", those are passed piecemeal to the driver, so while
the PRE_BRIDGE_FLAGS listener knows what changed because it has the
"mask", the BRIDGE_FLAGS listener doesn't, because it only has the final
value. But certain drivers can offload only certain combinations of
settings, like for example they cannot change unicast flooding
independently of multicast flooding - they must be both on or both off.
The way the information is passed to switchdev makes drivers not
expressive enough, and unable to reject this request ahead of time, in
the PRE_BRIDGE_FLAGS notifier, so they are forced to reject it during
the deferred BRIDGE_FLAGS attribute, where the rejection is currently
ignored.

This patch also changes drivers to make use of the "mask" field for edge
detection when possible.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: configure better brport flags when ports leave the bridge

For a DSA switch port operating in standalone mode, address learning
doesn't make much sense since that is a bridge function. In fact,
address learning even breaks setups such as this one:

+---------------------------------------------+
| |
| +-------------------+ |
| | br0 | send receive |
| +--------+-+--------+ +--------+ +--------+ |
| | | | | | | | | |
| | swp0 | | swp1 | | swp2 | | swp3 | |
| | | | | | | | | |
+-+--------+-+--------+-+--------+-+--------+-+
| ^ | ^
| | | |
| +-----------+ |
| |
+--------------------------------+

because if the switch has a single FDB (can offload a single bridge)
then source address learning on swp3 can "steal" the source MAC address
of swp2 from br0's FDB, because learning frames coming from swp2 will be
done twice: first on the swp1 ingress port, second on the swp3 ingress
port. So the hardware FDB will become out of sync with the software
bridge, and when swp2 tries to send one more packet towards swp1, the
ASIC will attempt to short-circuit the forwarding path and send it
directly to swp3 (since that's the last port it learned that address on),
which it obviously can't, because swp3 operates in standalone mode.

So DSA drivers operating in standalone mode should still configure a
list of bridge port flags even when they are standalone. Currently DSA
attempts to call dsa_port_bridge_flags with 0, which disables egress
flooding of unknown unicast and multicast, something which doesn't make
much sense. For the switches that implement .port_egress_floods - b53
and mv88e6xxx, it probably doesn't matter too much either, since they
can possibly inject traffic from the CPU into a standalone port,
regardless of MAC DA, even if egress flooding is turned off for that
port, but certainly not all DSA switches can do that - sja1105, for
example, can't. So it makes sense to use a better common default there,
such as "flood everything".

It should also be noted that what DSA calls "dsa_port_bridge_flags()"
is a degenerate name for just calling .port_egress_floods(), since
nothing else is implemented - not learning, in particular. But disabling
address learning, something that this driver is also coding up for, will
be supported by individual drivers once .port_egress_floods is replaced
with a more generic .port_bridge_flags.

Previous attempts to code up this logic have been in the common bridge
layer, but as pointed out by Ido Schimmel, there are corner cases that
are missed when doing that:
https://patchwork.kernel.org/project/netdevbpf/patch/20210209151936.97382-5-olteanv@gmail.com/

So, at least for now, let's leave DSA in charge of setting port flags
before and after the bridge join and leave.

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>

net: dsa: add support for offloading HSR

Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion
tag removal, duplicate generation and forwarding on DSA switches.

Add DSA_NOTIFIER_HSR_JOIN and DSA_NOTIFIER_HSR_LEAVE which trigger calls
to .port_hsr_join and .port_hsr_leave in the DSA driver for the switch.

The DSA switch driver should then set netdev feature flags for the
HSR/PRP operation that it offloads.
NETIF_F_HW_HSR_TAG_INS
NETIF_F_HW_HSR_TAG_RM
NETIF_F_HW_HSR_FWD
NETIF_F_HW_HSR_DUP

Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: allow changing the tag protocol via the "tagging" device attribute

Currently DSA exposes the following sysfs:
$ cat /sys/class/net/eno2/dsa/tagging
ocelot

which is a read-only device attribute, introduced in the kernel as
commit 98cdb4807123 ("net: dsa: Expose tagging protocol to user-space"),
and used by libpcap since its commit 993db3800d7d ("Add support for DSA
link-layer types").

It would be nice if we could extend this device attribute by making it
writable:
$ echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging

This is useful with DSA switches that can make use of more than one
tagging protocol. It may be useful in dsa_loop in the future too, to
perform offline testing of various taggers, or for changing between dsa
and edsa on Marvell switches, if that is desirable.

In terms of implementation, drivers can support this feature by
implementing .change_tag_protocol, which should always leave the switch
in a consistent state: either with the new protocol if things went well,
or with the old one if something failed. Teardown of the old protocol,
if necessary, must be handled by the driver.

Some things remain as before:
- The .get_tag_protocol is currently only called at probe time, to load
the initial tagging protocol driver. Nonetheless, new drivers should
report the tagging protocol in current use now.
- The driver should manage by itself the initial setup of tagging
protocol, no later than the .setup() method, as well as destroying
resources used by the last tagger in use, no earlier than the
.teardown() method.

For multi-switch DSA trees, error handling is a bit more complicated,
since e.g. the 5th out of 7 switches may fail to change the tag
protocol. When that happens, a revert to the original tag protocol is
attempted, but that may fail too, leaving the tree in an inconsistent
state despite each individual switch implementing .change_tag_protocol
transactionally. Since the intersection between drivers that implement
.change_tag_protocol and drivers that support D in DSA is currently the
empty set, the possibility for this error to happen is ignored for now.

Testing:

$ insmod mscc_felix.ko
[ 79.549784] mscc_felix 0000:00:00.5: Adding to iommu group 14
[ 79.565712] mscc_felix 0000:00:00.5: Failed to register DSA switch: -517
$ insmod tag_ocelot.ko
$ rmmod mscc_felix.ko
$ insmod mscc_felix.ko
[ 97.261724] libphy: VSC9959 internal MDIO bus: probed
[ 97.267363] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 0
[ 97.274998] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 1
[ 97.282561] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 2
[ 97.289700] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 3
[ 97.599163] mscc_felix 0000:00:00.5 swp0 (uninitialized): PHY [0000:00:00.3:10] driver [Microsemi GE VSC8514 SyncE] (irq=POLL)
[ 97.862034] mscc_felix 0000:00:00.5 swp1 (uninitialized): PHY [0000:00:00.3:11] driver [Microsemi GE VSC8514 SyncE] (irq=POLL)
[ 97.950731] mscc_felix 0000:00:00.5 swp0: configuring for inband/qsgmii link mode
[ 97.964278] 8021q: adding VLAN 0 to HW filter on device swp0
[ 98.146161] mscc_felix 0000:00:00.5 swp2 (uninitialized): PHY [0000:00:00.3:12] driver [Microsemi GE VSC8514 SyncE] (irq=POLL)
[ 98.238649] mscc_felix 0000:00:00.5 swp1: configuring for inband/qsgmii link mode
[ 98.251845] 8021q: adding VLAN 0 to HW filter on device swp1
[ 98.433916] mscc_felix 0000:00:00.5 swp3 (uninitialized): PHY [0000:00:00.3:13] driver [Microsemi GE VSC8514 SyncE] (irq=POLL)
[ 98.485542] mscc_felix 0000:00:00.5: configuring for fixed/internal link mode
[ 98.503584] mscc_felix 0000:00:00.5: Link is Up - 2.5Gbps/Full - flow control rx/tx
[ 98.527948] device eno2 entered promiscuous mode
[ 98.544755] DSA: tree 0 setup

$ ping 10.0.0.1
PING 10.0.0.1 (10.0.0.1): 56 data bytes
64 bytes from 10.0.0.1: seq=0 ttl=64 time=2.337 ms
64 bytes from 10.0.0.1: seq=1 ttl=64 time=0.754 ms
^C
- 10.0.0.1 ping statistics -
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.754/1.545/2.337 ms

$ cat /sys/class/net/eno2/dsa/tagging
ocelot
$ cat ./test_ocelot_8021q.sh
#!/bin/bash

ip link set swp0 down
ip link set swp1 down
ip link set swp2 down
ip link set swp3 down
ip link set swp5 down
ip link set eno2 down
echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging
ip link set eno2 up
ip link set swp0 up
ip link set swp1 up
ip link set swp2 up
ip link set swp3 up
ip link set swp5 up
$ ./test_ocelot_8021q.sh
./test_ocelot_8021q.sh: line 9: echo: write error: Protocol not available
$ rmmod tag_ocelot.ko
rmmod: can't unload module 'tag_ocelot': Resource temporarily unavailable
$ insmod tag_ocelot_8021q.ko
$ ./test_ocelot_8021q.sh
$ cat /sys/class/net/eno2/dsa/tagging
ocelot-8021q
$ rmmod tag_ocelot.ko
$ rmmod tag_ocelot_8021q.ko
rmmod: can't unload module 'tag_ocelot_8021q': Resource temporarily unavailable
$ ping 10.0.0.1
PING 10.0.0.1 (10.0.0.1): 56 data bytes
64 bytes from 10.0.0.1: seq=0 ttl=64 time=0.953 ms
64 bytes from 10.0.0.1: seq=1 ttl=64 time=0.787 ms
64 bytes from 10.0.0.1: seq=2 ttl=64 time=0.771 ms
$ rmmod mscc_felix.ko
[ 645.544426] mscc_felix 0000:00:00.5: Link is Down
[ 645.838608] DSA: tree 0 torn down
$ rmmod tag_ocelot_8021q.ko

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: document the existing switch tree notifiers and add a new one

The existence of dsa_broadcast has generated some confusion in the past:
https://www.mail-archive.com/netdev@vger.kernel.org/msg365042.html

So let's document the existing dsa_port_notify and dsa_broadcast
functions and explain when each of them should be used.

Also, in fact, the in-between function has always been there but was
lacking a name, and is the main reason for this patch: dsa_tree_notify.
Refactor dsa_broadcast to use it.

This patch also moves dsa_broadcast (a top-level function) to dsa2.c,
where it really belonged in the first place, but had no companion so it
stood with dsa_port_notify.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: Link aggregation support

Monitor the following events and notify the driver when:

- A DSA port joins/leaves a LAG.
- A LAG, made up of DSA ports, joins/leaves a bridge.
- A DSA port in a LAG is enabled/disabled (enabled meaning
"distributing" in 802.3ad LACP terms).

When a LAG joins a bridge, the DSA subsystem will treat that as each
individual port joining the bridge. The driver may look at the port's
LAG device pointer to see if it is associated with any LAG, if that is
required. This is analogue to how switchdev events are replicated out
to all lower devices when reaching e.g. a LAG.

Drivers can optionally request that DSA maintain a linear mapping from
a LAG ID to the corresponding netdev by setting ds->num_lag_ids to the
desired size.

In the event that the hardware is not capable of offloading a
particular LAG for any reason (the typical case being use of exotic
modes like broadcast), DSA will take a hands-off approach, allowing
the LAG to be formed as a pure software construct. This is reported
back through the extended ACK, but is otherwise transparent to the
user.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: remove the transactional logic from ageing time notifiers

Remove the shim introduced in DSA for offloading the bridge ageing time
from switchdev, by first checking whether the ageing time is within the
range limits requested by the driver.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: switchdev: remove the transaction structure from port attributes

Since the introduction of the switchdev API, port attributes were
transmitted to drivers for offloading using a two-step transactional
model, with a prepare phase that was supposed to catch all errors, and a
commit phase that was supposed to never fail.

Some classes of failures can never be avoided, like hardware access, or
memory allocation. In the latter case, merely attempting to move the
memory allocation to the preparation phase makes it impossible to avoid
memory leaks, since commit 91cf8eceffc1 ("switchdev: Remove unused
transaction item queue") which has removed the unused mechanism of
passing on the allocated memory between one phase and another.

It is time we admit that separating the preparation from the commit
phase is something that is best left for the driver to decide, and not
something that should be baked into the API, especially since there are
no switchdev callers that depend on this.

This patch removes the struct switchdev_trans member from switchdev port
attribute notifier structures, and converts drivers to not look at this
member.

In part, this patch contains a revert of my previous commit 2e554a7a5d8a
("net: dsa: propagate switchdev vlan_filtering prepare phase to
drivers").

For the most part, the conversion was trivial except for:
- Rocker's world implementation based on Broadcom OF-DPA had an odd
implementation of ofdpa_port_attr_bridge_flags_set. The conversion was
done mechanically, by pasting the implementation twice, then only
keeping the code that would get executed during prepare phase on top,
then only keeping the code that gets executed during the commit phase
on bottom, then simplifying the resulting code until this was obtained.
- DSA's offloading of STP state, bridge flags, VLAN filtering and
multicast router could be converted right away. But the ageing time
could not, so a shim was introduced and this was left for a further
commit.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek
Reviewed-by: Linus Walleij <linus.walleij@linaro.org> # RTL8366RB
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: switchdev: remove the transaction structure from port object notifiers

Since the introduction of the switchdev API, port objects were
transmitted to drivers for offloading using a two-step transactional
model, with a prepare phase that was supposed to catch all errors, and a
commit phase that was supposed to never fail.

Some classes of failures can never be avoided, like hardware access, or
memory allocation. In the latter case, merely attempting to move the
memory allocation to the preparation phase makes it impossible to avoid
memory leaks, since commit 91cf8eceffc1 ("switchdev: Remove unused
transaction item queue") which has removed the unused mechanism of
passing on the allocated memory between one phase and another.

It is time we admit that separating the preparation from the commit
phase is something that is best left for the driver to decide, and not
something that should be baked into the API, especially since there are
no switchdev callers that depend on this.

This patch removes the struct switchdev_trans member from switchdev port
object notifier structures, and converts drivers to not look at this
member.

Where driver conversion is trivial (like in the case of the Marvell
Prestera driver, NXP DPAA2 switch, TI CPSW, and Rocker drivers), it is
done in this patch.

Where driver conversion needs more attention (DSA, Mellanox Spectrum),
the conversion is left for subsequent patches and here we only fake the
prepare/commit phases at a lower level, just not in the switchdev
notifier itself.

Where the code has a natural structure that is best left alone as a
preparation and a commit phase (as in the case of the Ocelot switch),
that structure is left in place, just made to not depend upon the
switchdev transactional model.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: propagate switchdev vlan_filtering prepare phase to drivers

A driver may refuse to enable VLAN filtering for any reason beyond what
the DSA framework cares about, such as:
- having tc-flower rules that rely on the switch being VLAN-aware
- the particular switch does not support VLAN, even if the driver does
(the DSA framework just checks for the presence of the .port_vlan_add
and .port_vlan_del pointers)
- simply not supporting this configuration to be toggled at runtime

Currently, when a driver rejects a configuration it cannot support, it
does this from the commit phase, which triggers various warnings in
switchdev.

So propagate the prepare phase to drivers, to give them the ability to
refuse invalid configurations cleanly and avoid the warnings.

Since we need to modify all function prototypes and check for the
prepare phase from within the drivers, take that opportunity and move
the existing driver restrictions within the prepare phase where that is
possible and easy.

Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Woojung Huh <woojung.huh@microchip.com>
Cc: Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>
Cc: Sean Wang <sean.wang@mediatek.com>
Cc: Landen Chao <Landen.Chao@mediatek.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Jonathan McDowell <noodles@earth.li>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: allow 8021q uppers while the bridge has vlan_filtering=0

When the bridge has VLAN awareness disabled there isn't any duplication
of functionality, since the bridge does not process VLAN. Don't deny
adding 8021q uppers to DSA switch ports in that case. The switch is
supposed to simply pass traffic leaving the VLAN tag as-is, and the
stack will happily strip the VLAN tag for all 8021q uppers that exist.

We need to ensure that there are no 8021q uppers when the user attempts
to enable bridge vlan_filtering.

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>

net: dsa: refuse configuration in prepare phase of dsa_port_vlan_filtering()

The current logic beats me a little bit. The comment that "bridge skips
-EOPNOTSUPP, so skip the prepare phase" was introduced in commit
fb2dabad69f0 ("net: dsa: support VLAN filtering switchdev attr").

I'm not sure:
(a) ok, the bridge skips -EOPNOTSUPP, but, so what, where are we
returning -EOPNOTSUPP?
(b) even if we are, and I'm just not seeing it, what is the causality
relationship between the bridge skipping -EOPNOTSUPP and DSA
skipping the prepare phase, and just returning zero?

One thing is certain beyond doubt though, and that is that DSA currently
refuses VLAN filtering from the "commit" phase instead of "prepare", and
that this is not a good thing:

ip link add br0 type bridge
ip link add br1 type bridge vlan_filtering 1
ip link set swp2 master br0
ip link set swp3 master br1
[ 3790.379389] 001: sja1105 spi0.1: VLAN filtering is a global setting
[ 3790.379399] 001: ------------[ cut here ]------------
[ 3790.379403] 001: WARNING: CPU: 1 PID: 515 at net/switchdev/switchdev.c:157 switchdev_port_attr_set_now+0x9c/0xa4
[ 3790.379420] 001: swp3: Commit of attribute (id=6) failed.
[ 3790.379533] 001: [<c11ff588>] (switchdev_port_attr_set_now) from [<c11b62e4>] (nbp_vlan_init+0x84/0x148)
[ 3790.379544] 001: [<c11b62e4>] (nbp_vlan_init) from [<c11a2ff0>] (br_add_if+0x514/0x670)
[ 3790.379554] 001: [<c11a2ff0>] (br_add_if) from [<c1031b5c>] (do_setlink+0x38c/0xab0)
[ 3790.379565] 001: [<c1031b5c>] (do_setlink) from [<c1036fe8>] (__rtnl_newlink+0x44c/0x748)
[ 3790.379573] 001: [<c1036fe8>] (__rtnl_newlink) from [<c1037328>] (rtnl_newlink+0x44/0x60)
[ 3790.379580] 001: [<c1037328>] (rtnl_newlink) from [<c10315fc>] (rtnetlink_rcv_msg+0x124/0x2f8)
[ 3790.379590] 001: [<c10315fc>] (rtnetlink_rcv_msg) from [<c10926b8>] (netlink_rcv_skb+0xb8/0x110)
[ 3790.379806] 001: ---[ end trace 0000000000000002 ]---
[ 3790.379819] 001: sja1105 spi0.1 swp3: failed to initialize vlan filtering on this port

So move the current logic that may fail (except ds->ops->port_vlan_filtering,
that is way harder) into the prepare stage of the switchdev transaction.

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>

Revert "net: dsa: Add more convenient functions for installing port VLANs"

This reverts commit 314f76d7a68bab0516aa52877944e6aacfa0fc3f.

Citing that commit message, the call graph was:

dsa_slave_vlan_rx_add_vid dsa_port_setup_8021q_tagging
| |
| |
| +-------------+
| |
v v
dsa_port_vid_add dsa_slave_port_obj_add
| |
+-------+ +-------+
| |
v v
dsa_port_vlan_add

Now that tag_8021q has its own ops structure, it no longer relies on
dsa_port_vid_add, and therefore on the dsa_switch_ops to install its
VLANs.

So dsa_port_vid_add now only has one single caller. So we can simplify
the call graph to what it was before, aka:

dsa_slave_vlan_rx_add_vid dsa_slave_port_obj_add
| |
+-------+ +-------+
| |
v v
dsa_port_vlan_add

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>

net: dsa: provide an option for drivers to always receive bridge VLANs

DSA assumes that a bridge which has vlan filtering disabled is not
vlan aware, and ignores all vlan configuration. However, the kernel
software bridge code allows configuration in this state.

This causes the kernel's idea of the bridge vlan state and the
hardware state to disagree, so "bridge vlan show" indicates a correct
configuration but the hardware lacks all configuration. Even worse,
enabling vlan filtering on a DSA bridge immediately blocks all traffic
which, given the output of "bridge vlan show", is very confusing.

Provide an option that drivers can set to indicate they want to receive
vlan configuration even when vlan filtering is disabled. At the very
least, this is safe for Marvell DSA bridges, which do not look up
ingress traffic in the VTU if the port is in 8021Q disabled state. It is
also safe for the Ocelot switch family. Whether this change is suitable
for all DSA bridges is not known.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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>

net: dsa: permit cross-chip bridging between all trees in the system

One way of utilizing DSA is by cascading switches which do not all have
compatible taggers. Consider the following real-life topology:

+---------------------------------------------------------------+
| LS1028A |
| +------------------------------+ |
| | DSA master for Felix | |
| |(internal ENETC port 2: eno2))| |
| +------------+------------------------------+-------------+ |
| | Felix embedded L2 switch | |
| | | |
| | +--------------+ +--------------+ +--------------+ | |
| | |DSA master for| |DSA master for| |DSA master for| | |
| | | SJA1105 1 | | SJA1105 2 | | SJA1105 3 | | |
| | |(Felix port 1)| |(Felix port 2)| |(Felix port 3)| | |
+--+-+--------------+---+--------------+---+--------------+--+--+

+-----------------------+ +-----------------------+ +-----------------------+
| SJA1105 switch 1 | | SJA1105 switch 2 | | SJA1105 switch 3 |
+-----+-----+-----+-----+ +-----+-----+-----+-----+ +-----+-----+-----+-----+
|sw1p0|sw1p1|sw1p2|sw1p3| |sw2p0|sw2p1|sw2p2|sw2p3| |sw3p0|sw3p1|sw3p2|sw3p3|
+-----+-----+-----+-----+ +-----+-----+-----+-----+ +-----+-----+-----+-----+

The above can be described in the device tree as follows (obviously not
complete):

mscc_felix {
dsa,member = <0 0>;
ports {
port@4 {
ethernet = <&enetc_port2>;
};
};
};

sja1105_switch1 {
dsa,member = <1 1>;
ports {
port@4 {
ethernet = <&mscc_felix_port1>;
};
};
};

sja1105_switch2 {
dsa,member = <2 2>;
ports {
port@4 {
ethernet = <&mscc_felix_port2>;
};
};
};

sja1105_switch3 {
dsa,member = <3 3>;
ports {
port@4 {
ethernet = <&mscc_felix_port3>;
};
};
};

Basically we instantiate one DSA switch tree for every hardware switch
in the system, but we still give them globally unique switch IDs (will
come back to that later). Having 3 disjoint switch trees makes the
tagger drivers "just work", because net devices are registered for the
3 Felix DSA master ports, and they are also DSA slave ports to the ENETC
port. So packets received on the ENETC port are stripped of their
stacked DSA tags one by one.

Currently, hardware bridging between ports on the same sja1105 chip is
possible, but switching between sja1105 ports on different chips is
handled by the software bridge. This is fine, but we can do better.

In fact, the dsa_8021q tag used by sja1105 is compatible with cascading.
In other words, a sja1105 switch can correctly parse and route a packet
containing a dsa_8021q tag. So if we could enable hardware bridging on
the Felix DSA master ports, cross-chip bridging could be completely
offloaded.

Such as system would be used as follows:

ip link add dev br0 type bridge && ip link set dev br0 up
for port in sw0p0 sw0p1 sw0p2 sw0p3 \
sw1p0 sw1p1 sw1p2 sw1p3 \
sw2p0 sw2p1 sw2p2 sw2p3; do
ip link set dev $port master br0
done

The above makes switching between ports on the same row be performed in
hardware, and between ports on different rows in software. Now assume
the Felix switch ports are called swp0, swp1, swp2. By running the
following extra commands:

ip link add dev br1 type bridge && ip link set dev br1 up
for port in swp0 swp1 swp2; do
ip link set dev $port master br1
done

the CPU no longer sees packets which traverse sja1105 switch boundaries
and can be forwarded directly by Felix. The br1 bridge would not be used
for any sort of traffic termination.

For this to work, we need to give drivers an opportunity to listen for
bridging events on DSA trees other than their own, and pass that other
tree index as argument. I have made the assumption, for the moment, that
the other existing DSA notifiers don't need to be broadcast to other
trees. That assumption might turn out to be incorrect. But in the
meantime, introduce a dsa_broadcast function, similar in purpose to
dsa_port_notify, which is used only by the bridging notifiers.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: Down cpu/dsa ports phylink will control

DSA and CPU ports can be configured in two ways. By default, the
driver should configure such ports to there maximum bandwidth. For
most use cases, this is sufficient. When this default is insufficient,
a phylink instance can be bound to such ports, and phylink will
configure the port, e.g. based on fixed-link properties. phylink
assumes the port is initially down. Given that the driver should have
already configured it to its maximum speed, ask the driver to down
the port before instantiating the phylink instance.

Fixes: 30c4a5b0aad8 ("net: mv88e6xxx: use resolved link config in mac_link_up()")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: configure the MTU for switch ports

It is useful be able to configure port policers on a switch to accept
frames of various sizes:

- Increase the MTU for better throughput from the default of 1500 if it
is known that there is no 10/100 Mbps device in the network.
- Decrease the MTU to limit the latency of high-priority frames under
congestion, or work around various network segments that add extra
headers to packets which can't be fragmented.

For DSA slave ports, this is mostly a pass-through callback, called
through the regular ndo ops and at probe time (to ensure consistency
across all supported switches).

The CPU port is called with an MTU equal to the largest configured MTU
of the slave ports. The assumption is that the user might want to
sustain a bidirectional conversation with a partner over any switch
port.

The DSA master is configured the same as the CPU port, plus the tagger
overhead. Since the MTU is by definition L2 payload (sans Ethernet
header), it is up to each individual driver to figure out if it needs to
do anything special for its frame tags on the CPU port (it shouldn't
except in special cases). So the MTU does not contain the tagger
overhead on the CPU port.
However the MTU of the DSA master, minus the tagger overhead, is used as
a proxy for the MTU of the CPU port, which does not have a net device.
This is to avoid uselessly calling the .change_mtu function on the CPU
port when nothing should change.

So it is safe to assume that the DSA master and the CPU port MTUs are
apart by exactly the tagger's overhead in bytes.

Some changes were made around dsa_master_set_mtu(), function which was
now removed, for 2 reasons:
- dev_set_mtu() already calls dev_validate_mtu(), so it's redundant to
do the same thing in DSA
- __dev_set_mtu() returns 0 if ops->ndo_change_mtu is an absent method
That is to say, there's no need for this function in DSA, we can safely
call dev_set_mtu() directly, take the rtnl lock when necessary, and just
propagate whatever errors get reported (since the user probably wants to
be informed).

Some inspiration (mainly in the MTU DSA notifier) was taken from a
vaguely similar patch from Murali and Florian, who are credited as
co-developers down below.

Co-developed-by: Murali Krishna Policharla <murali.policharla@broadcom.com>
Signed-off-by: Murali Krishna Policharla <murali.policharla@broadcom.com>
Co-developed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: warn if phylink_mac_link_state returns error

Issue a warning to the kernel log if phylink_mac_link_state() returns
an error. This should not occur, but let's make it visible.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Don't instantiate phylink for CPU/DSA ports unless needed

By default, DSA drivers should configure CPU and DSA ports to their
maximum speed. In many configurations this is sufficient to make the
link work.

In some cases it is necessary to configure the link to run slower,
e.g. because of limitations of the SoC it is connected to. Or back to
back PHYs are used and the PHY needs to be driven in order to
establish link. In this case, phylink is used.

Only instantiate phylink if it is required. If there is no PHY, or no
fixed link properties, phylink can upset a link which works in the
default configuration.

Fixes: 0e27921816ad ("net: dsa: Use PHYLINK for the CPU/DSA ports")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: fix phylink_start()/phylink_stop() calls

Place phylink_start()/phylink_stop() inside dsa_port_enable() and
dsa_port_disable(), which ensures that we call phylink_stop() before
tearing down phylink - which is a documented requirement. Failure
to do so can cause use-after-free bugs.

Fixes: 0e27921816ad ("net: dsa: Use PHYLINK for the CPU/DSA ports")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: propagate resolved link config via mac_link_up()

Propagate the resolved link configuration down via DSA's
phylink_mac_link_up() operation to allow split PCS/MAC to work.

Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: phylink: propagate resolved link config via mac_link_up()

Propagate the resolved link parameters via the mac_link_up() call for
MACs that do not automatically track their PCS state. We propagate the
link parameters via function arguments so that inappropriate members
of struct phylink_link_state can't be accessed, and creating a new
structure just for this adds needless complexity to the API.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Pass pcs_poll flag from driver to PHYLINK

The DSA drivers that implement .phylink_mac_link_state should normally
register an interrupt for the PCS, from which they should call
phylink_mac_change(). However not all switches implement this, and those
who don't should set this flag in dsa_switch in the .setup callback, so
that PHYLINK will poll for a few ms until the in-band AN link timer
expires and the PCS state settles.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Make PHYLINK related function static again

Commit 77373d49de22 ("net: dsa: Move the phylink driver calls into
port.c") moved and exported a bunch of symbols, but they are not used
outside of net/dsa/port.c at the moment, so no reason to export them.

Reported-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: phylink: rename mac_link_state() op to mac_pcs_get_state()

Rename the mac_link_state() method to mac_pcs_get_state() to make it
clear that it should be returning the MACs PCS current state, which
is used for inband negotiation rather than just reading back what the
MAC has been configured for. Update the documentation to explicitly
mention that this is for inband.

We drop the return value as well; most of phylink doesn't check the
return value and it is not clear what it should do on error - instead
arrange for state->link to be false.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

net: of_get_phy_mode: Change API to solve int/unit warnings

Before this change of_get_phy_mode() returned an enum,
phy_interface_t. On error, -ENODEV etc, is returned. If the result of
the function is stored in a variable of type phy_interface_t, and the
compiler has decided to represent this as an unsigned int, comparision
with -ENODEV etc, is a signed vs unsigned comparision.

Fix this problem by changing the API. Make the function return an
error, or 0 on success, and pass a pointer, of type phy_interface_t,
where the phy mode should be stored.

v2:
Return with *interface set to PHY_INTERFACE_MODE_NA on error.
Add error checks to all users of of_get_phy_mode()
Fixup a few reverse christmas tree errors
Fixup a few slightly malformed reverse christmas trees

v3:
Fix 0-day reported errors.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: check bridge VLAN in slave operations

The bridge VLANs are not offloaded by dsa_port_vlan_* if the port is
not bridged or if its bridge is not VLAN aware.

This is a good thing but other corners of DSA, such as the tag_8021q
driver, may need to program VLANs regardless the bridge state.

And also because bridge_dev is specific to user ports anyway, move
these checks were it belongs, one layer up in the slave code.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Suggested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: do not skip -EOPNOTSUPP in dsa_port_vid_add

Currently dsa_port_vid_add returns 0 if the switch returns -EOPNOTSUPP.

This function is used in the tag_8021q.c code to offload the PVID of
ports, which would simply not work if .port_vlan_add is not supported
by the underlying switch.

Do not skip -EOPNOTSUPP in dsa_port_vid_add but only when necessary,
that is to say in dsa_slave_vlan_rx_add_vid.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: remove calls to genphy_config_init

Supported PHY features are either auto-detected or explicitly set.
In both cases calling genphy_config_init isn't needed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add support for BRIDGE_MROUTER attribute

This patch adds support for enabling or disabling the flooding of
unknown multicast traffic on the CPU ports, depending on the value
of the switchdev SWITCHDEV_ATTR_ID_BRIDGE_MROUTER attribute.

The current behavior is kept unchanged but a user can now prevent
the CPU conduit to be flooded with a lot of unregistered traffic that
the network stack needs to filter in software with e.g.:

echo 0 > /sys/class/net/br0/multicast_router

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: do not check orig_dev in vlan del

The current DSA code handling switchdev objects does not recurse into
the lower devices thus is never called with an orig_dev member being
a bridge device, hence remove this useless check.

At the same time, remove the comments about the callers, which is
unlikely to be updated if the code changes and thus will be confusing.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Deal with non-existing PHY/fixed-link

We need to specifically deal with phylink_of_phy_connect() returning
-ENODEV, because this can happen when a CPU/DSA port does connect
neither to a PHY, nor has a fixed-link property. This is a valid use
case that is permitted by the binding and indicates to the switch:
auto-configure port with maximum capabilities.

Fixes: 0e27921816ad ("net: dsa: Use PHYLINK for the CPU/DSA ports")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

Based on 1 normalized pattern(s):

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

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

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

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: dsa: Use PHYLINK for the CPU/DSA ports

For DSA switches that do not have an .adjust_link callback, aka those
who transitioned totally to the PHYLINK-compliant API, use PHYLINK to
drive the CPU/DSA ports.

The PHYLIB usage and .adjust_link are kept but deprecated, and users are
asked to transition from it. The reason why we can't do anything for
them is because PHYLINK does not wrap the fixed-link state behind a
phydev object, so we cannot wrap .phylink_mac_config into .adjust_link
unless we fabricate a phy_device structure.

For these ports, the newly introduced PHYLINK_DEV operation type is
used and the dsa_switch device structure is passed to PHYLINK for
printing purposes. The handling of the PHYLINK_NETDEV and PHYLINK_DEV
PHYLINK instances is common from the perspective of the driver.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Move the phylink driver calls into port.c

In order to have a common handling of PHYLINK for the slave and non-user
ports, the DSA core glue logic (between PHYLINK and the driver) must use
an API that does not rely on a struct net_device.

These will also be called by the CPU-port-handling code in a further
patch.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Suggested-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Export symbols for dsa_port_vid_{add, del}

This is needed so that the newly introduced tag_8021q may access these
core DSA functions when built as a module.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Add more convenient functions for installing port VLANs

This hides the need to perform a two-phase transaction and construct a
switchdev_obj_port_vlan struct.

Call graph (including a function that will be introduced in a follow-up
patch) looks like this now (same for the *_vlan_del function):

dsa_slave_vlan_rx_add_vid dsa_port_setup_8021q_tagging
| |
| |
| +-------------+
| |
v v
dsa_port_vid_add dsa_slave_port_obj_add
| |
+-------+ +-------+
| |
v v
dsa_port_vlan_add

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Skip calling .port_vlan_filtering on no change

Even if VLAN filtering is global, DSA will call this callback once per
each port. Drivers should not have to compare the global state with the
requested change. So let DSA do it.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Keep the vlan_filtering setting in dsa_switch if it's global

The current behavior is not as obvious as one would assume (which is
that, if the driver set vlan_filtering_is_global = 1, then checking any
dp->vlan_filtering would yield the same result). Only the ports which
are actively enslaved into a bridge would have vlan_filtering set.

This makes it tricky for drivers to check what the global state is.
So fix this and make the struct dsa_switch hold this global setting.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Be aware of switches where VLAN filtering is a global setting

On some switches, the action of whether to parse VLAN frame headers and use
that information for ingress admission is configurable, but not per
port. Such is the case for the Broadcom BCM53xx and the NXP SJA1105
families, for example. In that case, DSA can prevent the bridge core
from trying to apply different VLAN filtering settings on net devices
that belong to the same switch.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Suggested-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Store vlan_filtering as a property of dsa_port

This allows drivers to query the VLAN setting imposed by the bridge
driver directly from DSA, instead of keeping their own state based on
the .port_vlan_filtering callback.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: fix a leaked reference by adding missing of_node_put

The call to of_parse_phandle returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
./net/dsa/port.c:294:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 284, but without a corresponding object release within this function.
./net/dsa/dsa2.c:627:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
./net/dsa/dsa2.c:630:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
./net/dsa/dsa2.c:636:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
./net/dsa/dsa2.c:639:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

dsa: Remove phydev parameter from disable_port call

No current DSA driver makes use of the phydev parameter passed to the
disable_port call. Remove it.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Add ndo_vlan_rx_{add, kill}_vid implementation

In order to properly support VLAN filtering being enabled/disabled on a
bridge, while having other ports being non bridge port members, we need
to support the ndo_vlan_rx_{add,kill}_vid callbacks in order to make
sure the non-bridge ports can continue receiving VLAN tags, even when
the switch is globally configured to do ingress/egress VID checking.

Since we can call dsa_port_vlan_{add,del} with a bridge_dev pointer
NULL, we now need to check that in these two functions.

We specifically deal with two possibly problematic cases:

- creating a bridge VLAN entry while there is an existing VLAN device
claiming that same VID

- creating a VLAN device while there is an existing bridge VLAN entry
with that VID

Those are both resolved with returning -EBUSY back to user-space.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Add setter for SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS

In preparation for removing SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS_SUPPORT,
add support for a function that processes the
SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS and
SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS attributes and returns not
supported for any flag set, since DSA does not currently support
toggling those bridge port attributes (yet).

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: enable flooding for bridge ports

Switches work by learning the MAC address for each attached station by
monitoring traffic from each station. When a station sends a packet,
the switch records which port the MAC address is connected to.

With IPv4 networking, before communication commences with a neighbour,
an ARP packet is broadcasted to all stations asking for the MAC address
corresponding with the IPv4. The desired station responds with an ARP
reply, and the ARP reply causes the switch to learn which port the
station is connected to.

With IPv6 networking, the situation is rather different. Rather than
broadcasting ARP packets, a "neighbour solicitation" is multicasted
rather than broadcasted. This multicast needs to reach the intended
station in order for the neighbour to be discovered.

Once a neighbour has been discovered, and entered into the sending
stations neighbour cache, communication can restart at a point later
without sending a new neighbour solicitation, even if the entry in
the neighbour cache is marked as stale. This can be after the MAC
address has expired from the forwarding cache of the DSA switch -
when that occurs, there is a long pause in communication.

Our DSA implementation for mv88e6xxx switches disables flooding of
multicast and unicast frames for bridged ports. As per the above
description, this is fine for IPv4 networking, since the broadcasted
ARP queries will be sent to and received by all stations on the same
network. However, this breaks IPv6 very badly - blocking neighbour
solicitations and later causing connections to stall.

The defaults that the Linux bridge code expect from bridges are for
unknown unicast and unknown multicast frames to be flooded to all ports
on the bridge, which is at odds to the defaults adopted by our DSA
implementation for mv88e6xxx switches.

This commit enables by default flooding of both unknown unicast and
unknown multicast frames whenever a port is added to a bridge, and
disables the flooding when a port leaves the bridge. This means that
mv88e6xxx DSA switches now behave as per the bridge(8) man page, and
IPv6 works flawlessly through such a switch.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add support for bridge flags

The Linux bridge implementation allows various properties of the bridge
to be controlled, such as flooding unknown unicast and multicast frames.
This patch adds the necessary DSA infrastructure to allow the Linux
bridge support to control these properties for DSA switches.

Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
[florian: Add missing dp and ds variables declaration to fix build]
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: fix unintended change of bridge interface STP state

When a DSA port is added to a bridge and brought up, the resulting STP
state programmed into the hardware depends on the order that these
operations are performed. However, the Linux bridge code believes that
the port is in disabled mode.

If the DSA port is first added to a bridge and then brought up, it will
be in blocking mode. If it is brought up and then added to the bridge,
it will be in disabled mode.

This difference is caused by DSA always setting the STP mode in
dsa_port_enable() whether or not this port is part of a bridge. Since
bridge always sets the STP state when the port is added, brought up or
taken down, it is unnecessary for us to manipulate the STP state.

Apparently, this code was copied from Rocker, and the very next day a
similar fix for Rocker was merged but was not propagated to DSA. See
e47172ab7e41 ("rocker: put port in FORWADING state after leaving bridge")

Fixes: b73adef67765 ("net: dsa: integrate with SWITCHDEV for HW bridging")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rocker, dsa, ethsw: Don't filter VLAN events on bridge itself

Due to an explicit check in rocker_world_port_obj_vlan_add(),
dsa_slave_switchdev_event() resp. port_switchdev_event(), VLAN objects
that are added to a device that is not a front-panel port device are
ignored. Therefore this check is immaterial.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dsa: port: Ignore bridge VLAN events

A follow-up patch enables emitting VLAN notifications for the bridge CPU
port in addition to the existing slave port notifications. These
notifications have orig_dev set to the bridge in question.

Because there's no specific support for these VLANs, just ignore the
notifications to maintain the current behavior.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Allow providing PHY statistics from CPU port

Implement the same type of ethtool diversion that we have for
ETH_SS_STATS and make it work with ETH_SS_PHY_STATS. This allows
providing PHY level statistics for CPU ports that are directly
connecting to a PHY device.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Add helper function to obtain PHY device of a given port

In preparation for having more call sites attempting to obtain a
reference against a PHY device corresponding to a particular port,
introduce a helper function for that purpose.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Support internal phy on 'cpu' port

This adds support for enabling the internal PHY for a 'cpu' port.
It has been tested on GE B850v3, B650v3 and B450v3, which have a
built-in MV88E6240 switch hardwired to a PCIe based network card.
On these machines the internal PHY of the i210 network card and
the Marvell switch are connected to each other and must be enabled
for properly using the switch. While the i210 PHY will be enabled
when the network interface is enabled, the switch's port is not
exposed as network interface. Additionally the mv88e6xxx driver
resets the chip during probe, so the PHY is disabled without this
patch.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Don't add vlans when vlan filtering is disabled

The software bridge can be build with vlan filtering support
included. However, by default it is turned off. In its turned off
state, it still passes VLANs via switchev, even though they are not to
be used. Don't pass these VLANs to the hardware. Only do so when vlan
filtering is enabled.

This fixes at least one corner case. There are still issues in other
corners, such as when vlan_filtering is later enabled.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add more const attributes

The notify mechanism does not need to modify the port it is notifying.
So make the parameter const.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move fixed link registration helpers

The new bindings (dsa2.c) and the old bindings (legacy.c) share two
helpers dsa_cpu_dsa_setup and dsa_cpu_dsa_destroy, used to register or
deregister a fixed PHY if a given port has a corresponding device node.

Unclutter the code by moving them into two new port.c helpers,
dsa_port_fixed_link_register_of and dsa_port_fixed_link_(un)register_of.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add port enable and disable helpers

Provide dsa_port_enable and dsa_port_disable helpers to respectively
enable and disable a switch port. This makes the dsa_port_set_state_now
helper static.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.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>

net: dsa: add port fdb dump

Dumping a DSA port's FDB entries is not specific to a DSA slave, so add
a dsa_port_fdb_dump function, similarly to dsa_port_fdb_add and
dsa_port_fdb_del.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Move FDB dump implementation inside DSA

>From all switchdev devices only DSA requires special FDB dump. This is due
to lack of ability for syncing the hardware learned FDBs with the bridge.
Due to this it is removed from switchdev and moved inside DSA.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Remove redundant MDB dump support

Currently the MDB HW database is synced with the bridge's one, thus,
There is no need to support special dump functionality.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Remove support for bypass bridge port attributes/vlan set

The bridge port attributes/vlan for DSA devices should be set only
from bridge code. Furthermore, The vlans are synced totally with the
bridge so there is no need for special dump support.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Remove switchdev dependency from DSA switch notifier chain

Currently, the switchdev objects are embedded inside the DSA notifier
info. This patch removes this dependency. This is done as a preparation
stage before adding support for learning FDB through the switchdev
notification chain.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Remove prepare phase for FDB

The prepare phase for FDB add is unneeded because most of DSA devices
can have failures during bus transactions (SPI, I2C, etc.), thus, the
prepare phase cannot guarantee success of the commit stage.

The support for learning FDB through notification chain, which will be
introduced in the following patches, will provide the ability to notify
back the bridge about successful offload.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: support cross-chip ageing time

Now that the switchdev bridge ageing time attribute is propagated to all
switch chips of the fabric, each switch can check if the requested value
is valid and program itself, so that the whole fabric shares a common
ageing time setting.

This is especially needed for switch chips in between others, containing
no bridge port members but evidently used in the data path.

To achieve that, remove the condition which skips the other switches. We
also don't need to identify the target switch anymore, thus remove the
sw_index member of the dsa_notifier_ageing_time_info notifier structure.

On ZII Dev Rev B (with two 88E6352 and one 88E6185) and ZII Dev Rev C
(with two 88E6390X), we have the following hardware configuration:

# ip link add name br0 type bridge
# ip link set master br0 dev lan6
br0: port 1(lan6) entered blocking state
br0: port 1(lan6) entered disabled state
# echo 2000 > /sys/class/net/br0/bridge/ageing_time

Before this patch:

zii-rev-b# cat /sys/kernel/debug/mv88e6xxx/sw*/age_time
300000
300000
15000

zii-rev-c# cat /sys/kernel/debug/mv88e6xxx/sw*/age_time
300000
18750

After this patch:

zii-rev-b# cat /sys/kernel/debug/mv88e6xxx/sw*/age_time
15000
15000
15000

zii-rev-c# cat /sys/kernel/debug/mv88e6xxx/sw*/age_time
18750
18750

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.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>

net: dsa: add VLAN notifier

Add two new DSA_NOTIFIER_VLAN_ADD and DSA_NOTIFIER_VLAN_DEL events to
notify not only a single switch, but all switches of a the fabric when
an VLAN entry is added or removed.

For the moment, keep the current behavior and ignore other switches.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add MDB notifier

Add two new DSA_NOTIFIER_MDB_ADD and DSA_NOTIFIER_MDB_DEL events to
notify not only a single switch, but all switches of a the fabric when
an MDB entry is added or removed.

For the moment, keep the current behavior and ignore other switches.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add FDB notifier

Add two new DSA_NOTIFIER_FDB_ADD and DSA_NOTIFIER_FDB_DEL events to
notify not only a single switch, but all switches of a the fabric when
an FDB entry is added or removed.

For the moment, keep the current behavior and ignore other switches.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: add notifier for ageing time

This patch keeps the port-wide ageing time handling code in
dsa_port_ageing_time, pushes the requested ageing time value in a new
switch fabric notification, and moves the switch-wide ageing time
handling code in dsa_switch_ageing_time.

This has the effect that now not only the switch that the target port
belongs to can be programmed, but all switches composing the switch
fabric. For the moment, keep the current behavior and ignore other
switches.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move VLAN handlers

Move the DSA port code which handles VLAN objects in port.c, where it
belongs.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move MDB handlers

Move the DSA port code which handles MDB objects in port.c, where it
belongs.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move FDB handlers

Move the DSA port code which handles FDB objects in port.c, where it
belongs.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move ageing time setter

Move the DSA port code which sets a port ageing time in port.c, where it
belongs.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move VLAN filtering setter

Move the DSA port code which sets VLAN filtering on a port in port.c,
where it belongs.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move bridging routines

Move the DSA port code which bridges a port in port.c, where it belongs.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: move port state setters

Add a new port.c file to hold all DSA port-wide logic. This patch moves
in the code which sets a port state.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>