Commit Graph

323 Commits

Author SHA1 Message Date
Álvaro Fernández Rojas
964dbf186e net: dsa: tag_brcm: add support for legacy tags
Add support for legacy Broadcom tags, which are similar to DSA_TAG_PROTO_BRCM.
These tags are used on BCM5325, BCM5365 and BCM63xx switches.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-17 12:24:36 -07:00
Horatiu Vultur
c595c4330d net: dsa: add MRP support
Add support for offloading MRP in HW. Currently implement the switchdev
calls 'SWITCHDEV_OBJ_ID_MRP', 'SWITCHDEV_OBJ_ID_RING_ROLE_MRP',
to allow to create MRP instances and to set the role of these instances.

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

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-16 14:47:46 -08:00
Vladimir Oltean
89153ed6eb net: dsa: propagate extack to .port_vlan_filtering
Some drivers can't dynamically change the VLAN filtering option, or
impose some restrictions, it would be nice to propagate this info
through netlink instead of printing it to a kernel log that might never
be read. Also netlink extack includes the module that emitted the
message, which means that it's easier to figure out which ones are
driver-generated errors as opposed to command misuse.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-14 17:38:12 -08:00
Vladimir Oltean
31046a5fd9 net: dsa: propagate extack to .port_vlan_add
Allow drivers to communicate their restrictions to user space directly,
instead of printing to the kernel log. Where the conversion would have
been lossy and things like VLAN ID could no longer be conveyed (due to
the lack of support for printf format specifier in netlink extack), I
chose to keep the messages in full form to the kernel log only, and
leave it up to individual driver maintainers to move more messages to
extack.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-14 17:38:11 -08:00
Vladimir Oltean
7c4bb540e9 net: dsa: tag_ocelot: create separate tagger for Seville
The ocelot tagger is a hot mess currently, it relies on memory
initialized by the attached driver for basic frame transmission.
This is against all that DSA tagging protocols stand for, which is that
the transmission and reception of a DSA-tagged frame, the data path,
should be independent from the switch control path, because the tag
protocol is in principle hot-pluggable and reusable across switches
(even if in practice it wasn't until very recently). But if another
driver like dsa_loop wants to make use of tag_ocelot, it couldn't.

This was done to have common code between Felix and Ocelot, which have
one bit difference in the frame header format. Quoting from commit
67c2404922 ("net: dsa: felix: create a template for the DSA tags on
xmit"):

    Other alternatives have been analyzed, such as:
    - Create a separate tag_seville.c: too much code duplication for just 1
      bit field difference.
    - Create a separate DSA_TAG_PROTO_SEVILLE under tag_ocelot.c, just like
      tag_brcm.c, which would have a separate .xmit function. Again, too
      much code duplication for just 1 bit field difference.
    - Allocate the template from the init function of the tag_ocelot.c
      module, instead of from the driver: couldn't figure out a method of
      accessing the correct port template corresponding to the correct
      tagger in the .xmit function.

The really interesting part is that Seville should have had its own
tagging protocol defined - it is not compatible on the wire with Ocelot,
even for that single bit. In principle, a packet generated by
DSA_TAG_PROTO_OCELOT when booted on NXP LS1028A would look in a certain
way, but when booted on NXP T1040 it would look differently. The reverse
is also true: a packet generated by a Seville switch would be
interpreted incorrectly by Wireshark if it was told it was generated by
an Ocelot switch.

Actually things are a bit more nuanced. If we concentrate only on the
DSA tag, what I said above is true, but Ocelot/Seville also support an
optional DSA tag prefix, which can be short or long, and it is possible
to distinguish the two taggers based on an integer constant put in that
prefix. Nonetheless, creating a separate tagger is still justified,
since the tag prefix is optional, and without it, there is again no way
to distinguish.

Claiming backwards binary compatibility is a bit more tough, since I've
already changed the format of tag_ocelot once, in commit 5124197ce5
("net: dsa: tag_ocelot: use a short prefix on both ingress and egress").
Therefore I am not very concerned with treating this as a bugfix and
backporting it to stable kernels (which would be another mess due to the
fact that there would be lots of conflicts with the other DSA_TAG_PROTO*
definitions). It's just simpler to say that the string values of the
taggers have ABI value starting with kernel 5.12, which will be when the
changing of tag protocol via /sys/class/net/<dsa-master>/dsa/tagging
goes live.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-14 17:31:44 -08:00
Vladimir Oltean
a8b659e7ff net: dsa: act as passthrough for bridge port flags
There are multiple ways in which a PORT_BRIDGE_FLAGS attribute can be
expressed by the bridge through switchdev, and not all of them can be
emulated by DSA mid-layer API at the same time.

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

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

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

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

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

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

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

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

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-12 17:08:04 -08:00
George McCollister
18596f504a net: dsa: add support for offloading HSR
Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion
tag removal, duplicate generation and forwarding on DSA switches.

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

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

Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-11 13:24:45 -08:00
Vladimir Oltean
7c83a7c539 net: dsa: add a second tagger for Ocelot switches based on tag_8021q
There are use cases for which the existing tagger, based on the NPI
(Node Processor Interface) functionality, is insufficient.

Namely:
- Frames injected through the NPI port bypass the frame analyzer, so no
  source address learning is performed, no TSN stream classification,
  etc.
- Flow control is not functional over an NPI port (PAUSE frames are
  encapsulated in the same Extraction Frame Header as all other frames)
- There can be at most one NPI port configured for an Ocelot switch. But
  in NXP LS1028A and T1040 there are two Ethernet CPU ports. The non-NPI
  port is currently either disabled, or operated as a plain user port
  (albeit an internally-facing one). Having the ability to configure the
  two CPU ports symmetrically could pave the way for e.g. creating a LAG
  between them, to increase bandwidth seamlessly for the system.

So there is a desire to have an alternative to the NPI mode. This change
keeps the default tagger for the Seville and Felix switches as "ocelot",
but it can be changed via the following device attribute:

echo ocelot-8021q > /sys/class/<dsa-master>/dsa/tagging

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-29 21:25:27 -08:00
Vladimir Oltean
53da0ebaad net: dsa: allow changing the tag protocol via the "tagging" device attribute
Currently DSA exposes the following sysfs:
$ cat /sys/class/net/eno2/dsa/tagging
ocelot

which is a read-only device attribute, introduced in the kernel as
commit 98cdb48071 ("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>
2021-01-29 21:24:39 -08:00
Vladimir Oltean
357f203bb3 net: dsa: keep a copy of the tagging protocol in the DSA switch tree
Cascading DSA switches can be done multiple ways. There is the brute
force approach / tag stacking, where one upstream switch, located
between leaf switches and the host Ethernet controller, will just
happily transport the DSA header of those leaf switches as payload.
For this kind of setups, DSA works without any special kind of treatment
compared to a single switch - they just aren't aware of each other.
Then there's the approach where the upstream switch understands the tags
it transports from its leaves below, as it doesn't push a tag of its own,
but it routes based on the source port & switch id information present
in that tag (as opposed to DMAC & VID) and it strips the tag when
egressing a front-facing port. Currently only Marvell implements the
latter, and Marvell DSA trees contain only Marvell switches.

So it is safe to say that DSA trees already have a single tag protocol
shared by all switches, and in fact this is what makes the switches able
to understand each other. This fact is also implied by the fact that
currently, the tagging protocol is reported as part of a sysfs installed
on the DSA master and not per port, so it must be the same for all the
ports connected to that DSA master regardless of the switch that they
belong to.

It's time to make this official and enforce it (yes, this also means we
won't have any "switch understands tag to some extent but is not able to
speak it" hardware oddities that we'll support in the future).

This is needed due to the imminent introduction of the dsa_switch_ops::
change_tag_protocol driver API. When that is introduced, we'll have
to notify switches of the tagging protocol that they're configured to
use. Currently the tag_ops structure pointer is held only for CPU ports.
But there are switches which don't have CPU ports and nonetheless still
need to be configured. These would be Marvell leaf switches whose
upstream port is just a DSA link. How do we inform these of their
tagging protocol setup/deletion?

One answer to the above would be: iterate through the DSA switch tree's
ports once, list the CPU ports, get their tag_ops, then iterate again
now that we have it, and notify everybody of that tag_ops. But what to
do if conflicts appear between one cpu_dp->tag_ops and another? There's
no escaping the fact that conflict resolution needs to be done, so we
can be upfront about it.

Ease our work and just keep the master copy of the tag_ops inside the
struct dsa_switch_tree. Reference counting is now moved to be per-tree
too, instead of per-CPU port.

There are many places in the data path that access master->dsa_ptr->tag_ops
and we would introduce unnecessary performance penalty going through yet
another indirection, so keep those right where they are.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-29 21:24:31 -08:00
Vladimir Oltean
2a6ef76303 net: dsa: add ops for devlink-sb
Switches that care about QoS might have hardware support for reserving
buffer pools for individual ports or traffic classes, and configuring
their sizes and thresholds. Through devlink-sb (shared buffers), this is
all configurable, as well as their occupancy being viewable.

Add the plumbing in DSA for these operations.

Individual drivers still need to call devlink_sb_register() with the
shared buffers they want to expose. A helper was not created in DSA for
this purpose (unlike, say, dsa_devlink_params_register), since in my
opinion it does not bring any benefit over plainly calling
devlink_sb_register() directly.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15 20:02:34 -08:00
George McCollister
54a52823a2 dsa: add support for Arrow XRS700x tag trailer
Add support for Arrow SpeedChips XRS700x single byte tag trailer. This
is modeled on tag_trailer.c which works in a similar way.

Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15 15:36:31 -08:00
Tobias Waldekranz
058102a6e9 net: dsa: Link aggregation support
Monitor the following events and notify the driver when:

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

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

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

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

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-14 17:11:56 -08:00
Oleksij Rempel
c2ec5f2ecf net: dsa: add optional stats64 support
Allow DSA drivers to export stats64

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-12 20:17:09 -08:00
Vladimir Oltean
1958d5815c net: dsa: remove the transactional logic from VLAN objects
It should be the driver's business to logically separate its VLAN
offloading into a preparation and a commit phase, and some drivers don't
need / can't do this.

So remove the transactional shim from DSA and let drivers propagate
errors directly from the .port_vlan_add callback.

It would appear that the code has worse error handling now than it had
before. DSA is the only in-kernel user of switchdev that offloads one
switchdev object to more than one port: for every VLAN object offloaded
to a user port, that VLAN is also offloaded to the CPU port. So the
"prepare for user port -> check for errors -> prepare for CPU port ->
check for errors -> commit for user port -> commit for CPU port"
sequence appears to make more sense than the one we are using now:
"offload to user port -> check for errors -> offload to CPU port ->
check for errors", but it is really a compromise. In the new way, we can
catch errors from the commit phase that we previously had to ignore.
But we have our hands tied and cannot do any rollback now: if we add a
VLAN on the CPU port and it fails, we can't do the rollback by simply
deleting it from the user port, because the switchdev API is not so nice
with us: it could have simply been there already, even with the same
flags. So we don't even attempt to rollback anything on addition error,
just leave whatever VLANs managed to get offloaded right where they are.
This should not be a problem at all in practice.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-11 16:00:57 -08:00
Vladimir Oltean
a52b2da778 net: dsa: remove the transactional logic from MDB entries
For many drivers, the .port_mdb_prepare callback was not a good opportunity
to avoid any error condition, and they would suppress errors found during
the actual commit phase.

Where a logical separation between the prepare and the commit phase
existed, the function that used to implement the .port_mdb_prepare
callback still exists, but now it is called directly from .port_mdb_add,
which was modified to return an int code.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek
Reviewed-by: Linus Wallei <linus.walleij@linaro.org> # RTL8366
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-11 16:00:57 -08:00
Vladimir Oltean
bae33f2b5a net: switchdev: remove the transaction structure from port attributes
Since the introduction of the switchdev API, port attributes were
transmitted to drivers for offloading using a two-step transactional
model, with a prepare phase that was supposed to catch all errors, and a
commit phase that was supposed to never fail.

Some classes of failures can never be avoided, like hardware access, or
memory allocation. In the latter case, merely attempting to move the
memory allocation to the preparation phase makes it impossible to avoid
memory leaks, since commit 91cf8eceff ("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 2e554a7a5d
("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>
2021-01-11 16:00:57 -08:00
Vladimir Oltean
1dbb130281 net: dsa: remove the DSA specific notifiers
This effectively reverts commit 60724d4bae ("net: dsa: Add support for
DSA specific notifiers"). The reason is that since commit 2f1e8ea726
("net: dsa: link interfaces with the DSA master to get rid of lockdep
warnings"), it appears that there is a generic way to achieve the same
purpose. The only user thus far, the Broadcom SYSTEMPORT driver, was
converted to use the generic notifiers.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-07 15:42:07 -08:00
Vladimir Oltean
a5e3c9ba92 net: dsa: export dsa_slave_dev_check
Using the NETDEV_CHANGEUPPER notifications, drivers can be aware when
they are enslaved to e.g. a bridge by calling netif_is_bridge_master().

Export this helper from DSA to get the equivalent functionality of
determining whether the upper interface of a CHANGEUPPER notifier is a
DSA switch interface or not.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-07 15:42:07 -08:00
Vladimir Oltean
f46b9b8ee8 net: dsa: move the Broadcom tag information in a separate header file
It is a bit strange to see something as specific as Broadcom SYSTEMPORT
bits in the main DSA include file. Move these away into a separate
header, and have the tagger and the SYSTEMPORT driver include them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-07 15:42:07 -08:00
Vladimir Oltean
d5f19486ce net: dsa: listen for SWITCHDEV_{FDB,DEL}_ADD_TO_DEVICE on foreign bridge neighbors
Some DSA switches (and not only) cannot learn source MAC addresses from
packets injected from the CPU. They only perform hardware address
learning from inbound traffic.

This can be problematic when we have a bridge spanning some DSA switch
ports and some non-DSA ports (which we'll call "foreign interfaces" from
DSA's perspective).

There are 2 classes of problems created by the lack of learning on
CPU-injected traffic:
- excessive flooding, due to the fact that DSA treats those addresses as
  unknown
- the risk of stale routes, which can lead to temporary packet loss

To illustrate the second class, consider the following situation, which
is common in production equipment (wireless access points, where there
is a WLAN interface and an Ethernet switch, and these form a single
bridging domain).

 AP 1:
 +------------------------------------------------------------------------+
 |                                          br0                           |
 +------------------------------------------------------------------------+
 +------------+ +------------+ +------------+ +------------+ +------------+
 |    swp0    | |    swp1    | |    swp2    | |    swp3    | |    wlan0   |
 +------------+ +------------+ +------------+ +------------+ +------------+
       |                                                       ^        ^
       |                                                       |        |
       |                                                       |        |
       |                                                    Client A  Client B
       |
       |
       |
 +------------+ +------------+ +------------+ +------------+ +------------+
 |    swp0    | |    swp1    | |    swp2    | |    swp3    | |    wlan0   |
 +------------+ +------------+ +------------+ +------------+ +------------+
 +------------------------------------------------------------------------+
 |                                          br0                           |
 +------------------------------------------------------------------------+
 AP 2

- br0 of AP 1 will know that Clients A and B are reachable via wlan0
- the hardware fdb of a DSA switch driver today is not kept in sync with
  the software entries on other bridge ports, so it will not know that
  clients A and B are reachable via the CPU port UNLESS the hardware
  switch itself performs SA learning from traffic injected from the CPU.
  Nonetheless, a substantial number of switches don't.
- the hardware fdb of the DSA switch on AP 2 may autonomously learn that
  Client A and B are reachable through swp0. Therefore, the software br0
  of AP 2 also may or may not learn this. In the example we're
  illustrating, some Ethernet traffic has been going on, and br0 from AP
  2 has indeed learnt that it can reach Client B through swp0.

One of the wireless clients, say Client B, disconnects from AP 1 and
roams to AP 2. The topology now looks like this:

 AP 1:
 +------------------------------------------------------------------------+
 |                                          br0                           |
 +------------------------------------------------------------------------+
 +------------+ +------------+ +------------+ +------------+ +------------+
 |    swp0    | |    swp1    | |    swp2    | |    swp3    | |    wlan0   |
 +------------+ +------------+ +------------+ +------------+ +------------+
       |                                                            ^
       |                                                            |
       |                                                         Client A
       |
       |
       |                                                         Client B
       |                                                            |
       |                                                            v
 +------------+ +------------+ +------------+ +------------+ +------------+
 |    swp0    | |    swp1    | |    swp2    | |    swp3    | |    wlan0   |
 +------------+ +------------+ +------------+ +------------+ +------------+
 +------------------------------------------------------------------------+
 |                                          br0                           |
 +------------------------------------------------------------------------+
 AP 2

- br0 of AP 1 still knows that Client A is reachable via wlan0 (no change)
- br0 of AP 1 will (possibly) know that Client B has left wlan0. There
  are cases where it might never find out though. Either way, DSA today
  does not process that notification in any way.
- the hardware FDB of the DSA switch on AP 1 may learn autonomously that
  Client B can be reached via swp0, if it receives any packet with
  Client 1's source MAC address over Ethernet.
- the hardware FDB of the DSA switch on AP 2 still thinks that Client B
  can be reached via swp0. It does not know that it has roamed to wlan0,
  because it doesn't perform SA learning from the CPU port.

Now Client A contacts Client B.
AP 1 routes the packet fine towards swp0 and delivers it on the Ethernet
segment.
AP 2 sees a frame on swp0 and its fdb says that the destination is swp0.
Hairpinning is disabled => drop.

This problem comes from the fact that these switches have a 'blind spot'
for addresses coming from software bridging. The generic solution is not
to assume that hardware learning can be enabled somehow, but to listen
to more bridge learning events. It turns out that the bridge driver does
learn in software from all inbound frames, in __br_handle_local_finish.
A proper SWITCHDEV_FDB_ADD_TO_DEVICE notification is emitted for the
addresses serviced by the bridge on 'foreign' interfaces. The software
bridge also does the right thing on migration, by notifying that the old
entry is deleted, so that does not need to be special-cased in DSA. When
it is deleted, we just need to delete our static FDB entry towards the
CPU too, and wait.

The problem is that DSA currently only cares about SWITCHDEV_FDB_ADD_TO_DEVICE
events received on its own interfaces, such as static FDB entries.

Luckily we can change that, and DSA can listen to all switchdev FDB
add/del events in the system and figure out if those events were emitted
by a bridge that spans at least one of DSA's own ports. In case that is
true, DSA will also offload that address towards its own CPU port, in
the eventuality that there might be bridge clients attached to the DSA
switch who want to talk to the station connected to the foreign
interface.

In terms of implementation, we need to keep the fdb_info->added_by_user
check for the case where the switchdev event was targeted directly at a
DSA switch port. But we don't need to look at that flag for snooped
events. So the check is currently too late, we need to move it earlier.
This also simplifies the code a bit, since we avoid uselessly allocating
and freeing switchdev_work.

We could probably do some improvements in the future. For example,
multi-bridge support is rudimentary at the moment. If there are two
bridges spanning a DSA switch's ports, and both of them need to service
the same MAC address, then what will happen is that the migration of one
of those stations will trigger the deletion of the FDB entry from the
CPU port while it is still used by other bridge. That could be improved
with reference counting but is left for another time.

This behavior needs to be enabled at driver level by setting
ds->assisted_learning_on_cpu_port = true. This is because we don't want
to inflict a potential performance penalty (accesses through
MDIO/I2C/SPI are expensive) to hardware that really doesn't need it
because address learning on the CPU port works there.

Reported-by: DENG Qingfang <dqfext@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-07 15:34:46 -08:00
Vladimir Oltean
e358bef7c3 net: dsa: Give drivers the chance to veto certain upper devices
Some switches rely on unique pvids to ensure port separation in
standalone mode, because they don't have a port forwarding matrix
configurable in hardware. So, setups like a group of 2 uppers with the
same VLAN, swp0.100 and swp1.100, will cause traffic tagged with VLAN
100 to be autonomously forwarded between these switch ports, in spite
of there being no bridge between swp0 and swp1.

These drivers need to prevent this from happening. They need to have
VLAN filtering enabled in standalone mode (so they'll drop frames tagged
with unknown VLANs) and they can only accept an 8021q upper on a port as
long as it isn't installed on any other port too. So give them the
chance to veto bad user requests.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
[Kurt: Pass info instead of ptr]
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-05 14:04:49 -08:00
Kurt Kanzenbach
01ef09caad net: dsa: Add tag handling for Hirschmann Hellcreek switches
The Hirschmann Hellcreek TSN switches have a special tagging protocol for frames
exchanged between the CPU port and the master interface. The format is a one
byte trailer indicating the destination or origin port.

It's quite similar to the Micrel KSZ tagging. That's why the implementation is
based on that code.

Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-05 14:04:49 -08:00
Vladimir Oltean
2e554a7a5d 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>
2020-10-05 05:56:48 -07:00
Andrew Lunn
7d1e2a1068 net: dsa: Add helper for converting devlink port to ds and port
Hide away from DSA drivers how devlink works.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-04 14:38:53 -07:00
Andrew Lunn
08156ba430 net: dsa: Add devlink port regions support to DSA
Allow DSA drivers to make use of devlink port regions, via simple
wrappers.

Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-04 14:38:53 -07:00
Andrew Lunn
3122433eb5 net: dsa: Register devlink ports before calling DSA driver setup()
DSA drivers want to create regions on devlink ports as well as the
devlink device instance, in order to export registers and other tables
per port. To keep all this code together in the drivers, have the
devlink ports registered early, so the setup() method can setup both
device and port devlink regions.

v3:
Remove dp->setup
Move common code out of switch statement.
Fix wrong goto

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-04 14:38:53 -07:00
Florian Fainelli
1dc0408cdf net: dsa: Call dsa_untag_bridge_pvid() from dsa_switch_rcv()
When a DSA switch driver needs to call dsa_untag_bridge_pvid(), it can
set dsa_switch::untag_brige_pvid to indicate this is necessary.

This is a pre-requisite to making sure that we are always calling
dsa_untag_bridge_pvid() after eth_type_trans() has been called.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 13:36:07 -07:00
Vladimir Oltean
7a6ffe764b net: dsa: point out the tail taggers
The Marvell 88E6060 uses tag_trailer.c and the KSZ8795, KSZ9477 and
KSZ9893 switches also use tail tags.

Tell that to the DSA core, since this makes a difference for the flow
dissector. Most switches break the parsing of frame headers, but these
ones don't, so no flow dissector adjustment needs to be done for them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-26 14:17:59 -07:00
Vladimir Oltean
9790cf20a8 net: dsa: add a generic procedure for the flow dissector
For all DSA formats that don't use tail tags, it looks like behind the
obscure number crunching they're all doing the same thing: locating the
real EtherType behind the DSA tag. Nonetheless, this is not immediately
obvious, so create a generic helper for those DSA taggers that put the
header before the EtherType.

Another assumption for the generic function is that the DSA tags are of
equal length on RX and on TX. Prior to the previous patch, this was not
true for ocelot and for gswip. The problem was resolved for ocelot, but
for gswip it still remains, so that can't use this helper yet.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-26 14:17:59 -07:00
Vladimir Oltean
2e8cb1b3db net: dsa: make the .flow_dissect tagger callback return void
There is no tagger that returns anything other than zero, so just change
the return type appropriately.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-26 14:17:59 -07:00
Vladimir Oltean
c3975400c8 net: dsa: allow drivers to request promiscuous mode on master
Currently DSA assumes that taggers don't mess with the destination MAC
address of the frames on RX. That is not always the case. Some DSA
headers are placed before the Ethernet header (ocelot), and others
simply mangle random bytes from the destination MAC address (sja1105
with its incl_srcpt option).

Currently the DSA master goes to promiscuous mode automatically when the
slave devices go too (such as when enslaved to a bridge), but in
standalone mode this is a problem that needs to be dealt with.

So give drivers the possibility to signal that their tagging protocol
will get randomly dropped otherwise, and let DSA deal with fixing that.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-26 14:17:58 -07:00
Andrew Lunn
0f06b855a9 net: dsa: wire up devlink info get
Allow the DSA drivers to implement the devlink call to get info info,
e.g. driver name, firmware version, ASIC ID, etc.

v2:
Combine declaration and the assignment on a single line.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18 18:18:30 -07:00
Andrew Lunn
97c82c2313 net: dsa: Add devlink regions support to DSA
Allow DSA drivers to make use of devlink regions, via simple wrappers.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18 18:17:45 -07:00
Andrew Lunn
ccc3e6b019 net: dsa: Add helper to convert from devlink to ds
Given a devlink instance, return the dsa switch it is associated to.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18 18:17:45 -07:00
Vladimir Oltean
5df5661a13 net: dsa: stop overriding master's ndo_get_phys_port_name
The purpose of this override is to give the user an indication of what
the number of the CPU port is (in DSA, the CPU port is a hardware
implementation detail and not a network interface capable of traffic).

However, it has always failed (by design) at providing this information
to the user in a reliable fashion.

Prior to commit 3369afba1e ("net: Call into DSA netdevice_ops
wrappers"), the behavior was to only override this callback if it was
not provided by the DSA master.

That was its first failure: if the DSA master itself was a DSA port or a
switchdev, then the user would not see the number of the CPU port in
/sys/class/net/eth0/phys_port_name, but the number of the DSA master
port within its respective physical switch.

But that was actually ok in a way. The commit mentioned above changed
that behavior, and now overrides the master's ndo_get_phys_port_name
unconditionally. That comes with problems of its own, which are worse in
a way.

The idea is that it's typical for switchdev users to have udev rules for
consistent interface naming. These are based, among other things, on
the phys_port_name attribute. If we let the DSA switch at the bottom
to start randomly overriding ndo_get_phys_port_name with its own CPU
port, we basically lose any predictability in interface naming, or even
uniqueness, for that matter.

So, there are reasons to let DSA override the master's callback (to
provide a consistent interface, a number which has a clear meaning and
must not be interpreted according to context), and there are reasons to
not let DSA override it (it breaks udev matching for the DSA master).

But, there is an alternative method for users to retrieve the number of
the CPU port of each DSA switch in the system:

  $ devlink port
  pci/0000:00:00.5/0: type eth netdev swp0 flavour physical port 0
  pci/0000:00:00.5/2: type eth netdev swp2 flavour physical port 2
  pci/0000:00:00.5/4: type notset flavour cpu port 4
  spi/spi2.0/0: type eth netdev sw0p0 flavour physical port 0
  spi/spi2.0/1: type eth netdev sw0p1 flavour physical port 1
  spi/spi2.0/2: type eth netdev sw0p2 flavour physical port 2
  spi/spi2.0/4: type notset flavour cpu port 4
  spi/spi2.1/0: type eth netdev sw1p0 flavour physical port 0
  spi/spi2.1/1: type eth netdev sw1p1 flavour physical port 1
  spi/spi2.1/2: type eth netdev sw1p2 flavour physical port 2
  spi/spi2.1/3: type eth netdev sw1p3 flavour physical port 3
  spi/spi2.1/4: type notset flavour cpu port 4

So remove this duplicated, unreliable and troublesome method. From this
patch on, the phys_port_name attribute of the DSA master will only
contain information about itself (if at all). If the users need reliable
information about the CPU port they're probably using devlink anyway.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23 15:14:58 -07:00
Florian Fainelli
9c0c7014f3 net: dsa: Setup dsa_netdev_ops
Now that we have all the infrastructure in place for calling into the
dsa_ptr->netdev_ops function pointers, install them when we configure
the DSA CPU/management interface and tear them down. The flow is
unchanged from before, but now we preserve equality of tests when
network device drivers do tests like dev->netdev_ops == &foo_ops which
was not the case before since we were allocating an entirely new
structure.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-20 16:48:22 -07:00
Florian Fainelli
4cfab35667 net: dsa: Add wrappers for overloaded ndo_ops
Add definitions for the dsa_netdevice_ops structure which is a subset of
the net_device_ops structure for the specific operations that we care
about overlaying on top of the DSA CPU port net_device and provide
inline stubs that take core managing whether DSA code is reachable.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-20 16:48:22 -07:00
Randy Dunlap
ab88d64a90 net: dsa.h: drop duplicate word in comment
Drop doubled word "to" in a comment.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-07-15 20:34:11 -07:00
Linus Walleij
efd7fe68f0 net: dsa: tag_rtl4_a: Implement Realtek 4 byte A tag
This implements the known parts of the Realtek 4 byte
tag protocol version 0xA, as found in the RTL8366RB
DSA switch.

It is designated as protocol version 0xA as a
different Realtek 4 byte tag format with protocol
version 0x9 is known to exist in the Realtek RTL8306
chips.

The tag and switch chip lacks public documentation, so
the tag format has been reverse-engineered from
packet dumps. As only ingress traffic has been available
for analysis an egress tag has not been possible to
develop (even using educated guesses about bit fields)
so this is as far as it gets. It is not known if the
switch even supports egress tagging.

Excessive attempts to figure out the egress tag format
was made. When nothing else worked, I just tried all bit
combinations with 0xannp where a is protocol and p is
port. I looped through all values several times trying
to get a response from ping, without any positive
result.

Using just these ingress tags however, the switch
functionality is vastly improved and the packets find
their way into the destination port without any
tricky VLAN configuration. On the D-Link DIR-685 the
LAN ports now come up and respond to ping without
any command line configuration so this is a real
improvement for users.

Egress packets need to be restricted to the proper
target ports using VLAN, which the RTL8366RB DSA
switch driver already sets up.

Cc: DENG Qingfang <dqfext@gmail.com>
Cc: Mauri Sandberg <sandberg@mailfence.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-08 15:36:19 -07:00
Po Liu
5f035af76e net:qos: police action offloading parameter 'burst' change to the original value
Since 'tcfp_burst' with TICK factor, driver side always need to recover
it to the original value, this patch moves the generic calculation and
recover to the 'burst' original value before offloading to device driver.

Signed-off-by: Po Liu <po.liu@nxp.com>
Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:33:42 -07:00
Russell King
54a0ed0df4 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>
2020-05-12 13:08:07 -07:00
Vladimir Oltean
3b7bc1f091 net: dsa: introduce a dsa_switch_find function
Somewhat similar to dsa_tree_find, dsa_switch_find returns a dsa_switch
structure pointer by searching for its tree index and switch index (the
parameters from dsa,member). To be used, for example, by drivers who
implement .crosschip_bridge_join and need a reference to the other
switch indicated to by the tree_index and sw_index arguments.

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>
2020-05-10 19:52:33 -07:00
Vladimir Oltean
f66a6a69f9 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>
2020-05-10 19:52:33 -07:00
Vladimir Oltean
9eb8eff0cf net: bridge: allow enslaving some DSA master network devices
Commit 8db0a2ee2c ("net: bridge: reject DSA-enabled master netdevices
as bridge members") added a special check in br_if.c in order to check
for a DSA master network device with a tagging protocol configured. This
was done because back then, such devices, once enslaved in a bridge
would become inoperative and would not pass DSA tagged traffic anymore
due to br_handle_frame returning RX_HANDLER_CONSUMED.

But right now we have valid use cases which do require bridging of DSA
masters. One such example is when the DSA master ports are DSA switch
ports themselves (in a disjoint tree setup). This should be completely
equivalent, functionally speaking, from having multiple DSA switches
hanging off of the ports of a switchdev driver. So we should allow the
enslaving of DSA tagged master network devices.

Instead of the regular br_handle_frame(), install a new function
br_handle_frame_dummy() on these DSA masters, which returns
RX_HANDLER_PASS in order to call into the DSA specific tagging protocol
handlers, and lift the restriction from br_add_if.

Suggested-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Suggested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-05-10 19:52:33 -07:00
Vladimir Oltean
e1eea81120 net: dsa: introduce a dsa_port_from_netdev public helper
As its implementation shows, this is synonimous with calling
dsa_slave_dev_check followed by dsa_slave_to_port, so it is quite simple
already and provides functionality which is already there.

However there is now a need for these functions outside dsa_priv.h, for
example in drivers that perform mirroring and redirection through
tc-flower offloads (they are given raw access to the flow_cls_offload
structure), where they need to call this function on act->dev.

But simply exporting dsa_slave_to_port would make it non-inline and
would result in an extra function call in the hotpath, as can be seen
for example in sja1105:

Before:

000006dc <sja1105_xmit>:
{
 6dc:	e92d4ff0 	push	{r4, r5, r6, r7, r8, r9, sl, fp, lr}
 6e0:	e1a04000 	mov	r4, r0
 6e4:	e591958c 	ldr	r9, [r1, #1420]	; 0x58c <- Inline dsa_slave_to_port
 6e8:	e1a05001 	mov	r5, r1
 6ec:	e24dd004 	sub	sp, sp, #4
	u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
 6f0:	e1c901d8 	ldrd	r0, [r9, #24]
 6f4:	ebfffffe 	bl	0 <dsa_8021q_tx_vid>
			6f4: R_ARM_CALL	dsa_8021q_tx_vid
	u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
 6f8:	e1d416b0 	ldrh	r1, [r4, #96]	; 0x60
	u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
 6fc:	e1a08000 	mov	r8, r0

After:

000006e4 <sja1105_xmit>:
{
 6e4:	e92d4ff0 	push	{r4, r5, r6, r7, r8, r9, sl, fp, lr}
 6e8:	e1a04000 	mov	r4, r0
 6ec:	e24dd004 	sub	sp, sp, #4
	struct dsa_port *dp = dsa_slave_to_port(netdev);
 6f0:	e1a00001 	mov	r0, r1
{
 6f4:	e1a05001 	mov	r5, r1
	struct dsa_port *dp = dsa_slave_to_port(netdev);
 6f8:	ebfffffe 	bl	0 <dsa_slave_to_port>
			6f8: R_ARM_CALL	dsa_slave_to_port
 6fc:	e1a09000 	mov	r9, r0
	u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
 700:	e1c001d8 	ldrd	r0, [r0, #24]
 704:	ebfffffe 	bl	0 <dsa_8021q_tx_vid>
			704: R_ARM_CALL	dsa_8021q_tx_vid

Because we want to avoid possible performance regressions, introduce
this new function which is designed to be public.

Suggested-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-07 17:31:57 -07:00
Vladimir Oltean
342971766c net: dsa: add port policers
The approach taken to pass the port policer methods on to drivers is
pragmatic. It is similar to the port mirroring implementation (in that
the DSA core does all of the filter block interaction and only passes
simple operations for the driver to implement) and dissimilar to how
flow-based policers are going to be implemented (where the driver has
full control over the flow_cls_offload data structure).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-30 11:44:00 -07:00
Vladimir Oltean
bff33f7e2a net: dsa: implement auto-normalization of MTU for bridge hardware datapath
Many switches don't have an explicit knob for configuring the MTU
(maximum transmission unit per interface).  Instead, they do the
length-based packet admission checks on the ingress interface, for
reasons that are easy to understand (why would you accept a packet in
the queuing subsystem if you know you're going to drop it anyway).

So it is actually the MRU that these switches permit configuring.

In Linux there only exists the IFLA_MTU netlink attribute and the
associated dev_set_mtu function. The comments like to play blind and say
that it's changing the "maximum transfer unit", which is to say that
there isn't any directionality in the meaning of the MTU word. So that
is the interpretation that this patch is giving to things: MTU == MRU.

When 2 interfaces having different MTUs are bridged, the bridge driver
MTU auto-adjustment logic kicks in: what br_mtu_auto_adjust() does is it
adjusts the MTU of the bridge net device itself (and not that of the
slave net devices) to the minimum value of all slave interfaces, in
order for forwarded packets to not exceed the MTU regardless of the
interface they are received and send on.

The idea behind this behavior, and why the slave MTUs are not adjusted,
is that normal termination from Linux over the L2 forwarding domain
should happen over the bridge net device, which _is_ properly limited by
the minimum MTU. And termination over individual slave devices is
possible even if those are bridged. But that is not "forwarding", so
there's no reason to do normalization there, since only a single
interface sees that packet.

The problem with those switches that can only control the MRU is with
the offloaded data path, where a packet received on an interface with
MRU 9000 would still be forwarded to an interface with MRU 1500. And the
br_mtu_auto_adjust() function does not really help, since the MTU
configured on the bridge net device is ignored.

In order to enforce the de-facto MTU == MRU rule for these switches, we
need to do MTU normalization, which means: in order for no packet larger
than the MTU configured on this port to be sent, then we need to limit
the MRU on all ports that this packet could possibly come from. AKA
since we are configuring the MRU via MTU, it means that all ports within
a bridge forwarding domain should have the same MTU.

And that is exactly what this patch is trying to do.

>From an implementation perspective, we try to follow the intent of the
user, otherwise there is a risk that we might livelock them (they try to
change the MTU on an already-bridged interface, but we just keep
changing it back in an attempt to keep the MTU normalized). So the MTU
that the bridge is normalized to is either:

 - The most recently changed one:

   ip link set dev swp0 master br0
   ip link set dev swp1 master br0
   ip link set dev swp0 mtu 1400

   This sequence will make swp1 inherit MTU 1400 from swp0.

 - The one of the most recently added interface to the bridge:

   ip link set dev swp0 master br0
   ip link set dev swp1 mtu 1400
   ip link set dev swp1 master br0

   The above sequence will make swp0 inherit MTU 1400 as well.

Suggested-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>
2020-03-27 16:07:25 -07:00
Vladimir Oltean
bfcb813203 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>
2020-03-27 16:07:24 -07:00
Vladimir Oltean
ed11bb1f96 net: dsa: Add bypass operations for the flower classifier-action filter
Due to the immense variety of classification keys and actions available
for tc-flower, as well as due to potentially very different DSA switch
capabilities, it doesn't make a lot of sense for the DSA mid layer to
even attempt to interpret these. So just pass them on to the underlying
switch driver.

DSA implements just the standard boilerplate for binding and unbinding
flow blocks to ports, since nobody wants to deal with that.

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>
2020-03-03 18:57:49 -08:00
Russell King
5b502a7b29 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>
2020-02-27 12:02:14 -08:00
Florian Fainelli
4d776482ec net: dsa: Get information about stacked DSA protocol
It is possible to stack multiple DSA switches in a way that they are not
part of the tree (disjoint) but the DSA master of a switch is a DSA
slave of another. When that happens switch drivers may have to know this
is the case so as to determine whether their tagging protocol has a
remove chance of working.

This is useful for specific switch drivers such as b53 where devices
have been known to be stacked in the wild without the Broadcom tag
protocol supporting that feature. This allows b53 to continue supporting
those devices by forcing the disabling of Broadcom tags on the outermost
switches if necessary.

The get_tag_protocol() function is therefore updated to gain an
additional enum dsa_tag_protocol argument which denotes the current
tagging protocol used by the DSA master we are attached to, else
DSA_TAG_PROTO_NONE for the top of the dsa_switch_tree.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-08 16:01:13 -08:00
Vladimir Oltean
787cac3f5a 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>
2020-01-05 23:22:32 -08:00
Vladimir Oltean
a68578c20a net: dsa: Make deferred_xmit private to sja1105
There are 3 things that are wrong with the DSA deferred xmit mechanism:

1. Its introduction has made the DSA hotpath ever so slightly more
   inefficient for everybody, since DSA_SKB_CB(skb)->deferred_xmit needs
   to be initialized to false for every transmitted frame, in order to
   figure out whether the driver requested deferral or not (a very rare
   occasion, rare even for the only driver that does use this mechanism:
   sja1105). That was necessary to avoid kfree_skb from freeing the skb.

2. Because L2 PTP is a link-local protocol like STP, it requires
   management routes and deferred xmit with this switch. But as opposed
   to STP, the deferred work mechanism needs to schedule the packet
   rather quickly for the TX timstamp to be collected in time and sent
   to user space. But there is no provision for controlling the
   scheduling priority of this deferred xmit workqueue. Too bad this is
   a rather specific requirement for a feature that nobody else uses
   (more below).

3. Perhaps most importantly, it makes the DSA core adhere a bit too
   much to the NXP company-wide policy "Innovate Where It Doesn't
   Matter". The sja1105 is probably the only DSA switch that requires
   some frames sent from the CPU to be routed to the slave port via an
   out-of-band configuration (register write) rather than in-band (DSA
   tag). And there are indeed very good reasons to not want to do that:
   if that out-of-band register is at the other end of a slow bus such
   as SPI, then you limit that Ethernet flow's throughput to effectively
   the throughput of the SPI bus. So hardware vendors should definitely
   not be encouraged to design this way. We do _not_ want more
   widespread use of this mechanism.

Luckily we have a solution for each of the 3 issues:

For 1, we can just remove that variable in the skb->cb and counteract
the effect of kfree_skb with skb_get, much to the same effect. The
advantage, of course, being that anybody who doesn't use deferred xmit
doesn't need to do any extra operation in the hotpath.

For 2, we can create a kernel thread for each port's deferred xmit work.
If the user switch ports are named swp0, swp1, swp2, the kernel threads
will be named swp0_xmit, swp1_xmit, swp2_xmit (there appears to be a 15
character length limit on kernel thread names). With this, the user can
change the scheduling priority with chrt $(pidof swp2_xmit).

For 3, we can actually move the entire implementation to the sja1105
driver.

So this patch deletes the generic implementation from the DSA core and
adds a new one, more adequate to the requirements of PTP TX
timestamping, in sja1105_main.c.

Suggested-by: Florian Fainelli <f.fainelli@gmail.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>
2020-01-05 15:13:13 -08:00
Oleksij Rempel
48fda74f0a net: dsa: add support for Atheros AR9331 TAG format
Add support for tag format used in Atheros AR9331 built-in switch.

Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-20 17:05:47 -08:00
Vladimir Oltean
8dce89aa5f net: dsa: ocelot: add tagger for Ocelot/Felix switches
While it is entirely possible that this tagger format is in fact more
generic than just these 2 switch families, I don't have that knowledge.
The Seville switch in NXP T1040 has a similar frame format, but there
are enough differences (e.g. DEST field starts at bit 57 instead of 56)
that calling this file tag_vitesse.c is a bit of a stretch at the
moment. The frame format has been listed in a comment so that people who
add support for further Vitesse switches can rework this tagger while
keeping compatibility with Felix.

The "ocelot" name was chosen instead of "felix" because even the Ocelot
switch can act as a DSA device when it is used in NPI mode, and the Felix
tagger format is almost identical. Currently it is only used for the
Felix switch embedded in the NXP LS1028A chip.

The ABI for this tagger should be considered "not stable" at the moment.
The DSA tag is always placed before the Ethernet header and therefore,
we are using the long prefix for RX tags to avoid putting the DSA master
port in promiscuous mode. Once there will be an API in DSA for drivers
to request DSA masters to be in promiscuous mode unconditionally, we
will switch to the "no prefix" extraction frame header, which will save
16 padding bytes for each RX frame.

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>
2019-11-15 12:32:16 -08:00
Andrew Lunn
5cd73fbd78 net: dsa: Add support for devlink resources
Add wrappers around the devlink resource API, so that DSA drivers can
register and unregister devlink resources.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-05 18:09:45 -08:00
Vivien Didelot
9c8ad1ab66 net: dsa: remove the dst->ds array
Now that the DSA ports are listed in the switch fabric, there is
no need to store the dsa_switch structures from the drivers in the
fabric anymore. So get rid of the dst->ds static array.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 14:26:38 -07:00
Vivien Didelot
96252b8e05 net: dsa: remove ds->rtable
Drivers do not use the ds->rtable static arrays anymore, get rid of it.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 14:26:38 -07:00
Vivien Didelot
c5f51765a1 net: dsa: list DSA links in the fabric
Implement a new list of DSA links in the switch fabric itself, to
provide an alterative to the ds->rtable static arrays.

At the same time, provide a new dsa_routing_port() helper to abstract
the usage of ds->rtable in drivers. If there's no port to reach a
given device, return the first invalid port, ds->num_ports. This avoids
potential signedness errors or the need to define special values.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 14:26:38 -07:00
Vivien Didelot
d607525bd9 net: dsa: return directly from dsa_to_port
Return directly from within the loop as soon as the port is found,
otherwise we won't return NULL if the end of the list is reached.

Fixes: b96ddf254b ("net: dsa: use ports list in dsa_to_port")
Signed-off-by: Vivien Didelot <vivien.didelot@gmail.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>
2019-10-29 12:07:49 -07:00
Andrew Lunn
6b29752423 net: dsa: Add support for devlink device parameters
Add plumbing to allow DSA drivers to register parameters with devlink.

To keep with the abstraction, the DSA drivers pass the ds structure to
these helpers, and the DSA core then translates that to the devlink
structure associated to the device.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-28 16:21:02 -07:00
Vivien Didelot
7e99e34701 net: dsa: remove dsa_switch_alloc helper
Now that ports are dynamically listed in the fabric, there is no need
to provide a special helper to allocate the dsa_switch structure. This
will give more flexibility to drivers to embed this structure as they
wish in their private structure.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 12:37:07 -07:00
Vivien Didelot
05f294a852 net: dsa: allocate ports on touch
Allocate the struct dsa_port the first time it is accessed with
dsa_port_touch, and remove the static dsa_port array from the
dsa_switch structure.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 12:37:07 -07:00
Vivien Didelot
da4561cda2 net: dsa: use ports list to setup default CPU port
Use the new ports list instead of iterating over switches and their
ports when setting up the default CPU port. Unassign it on teardown.

Now that we can iterate over multiple CPU ports, remove dst->cpu_dp.

At the same time, provide a better error message for CPU-less tree.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 12:37:07 -07:00
Vivien Didelot
fb35c60cba net: dsa: use ports list to setup switches
Use the new ports list instead of iterating over switches and their
ports when setting up the switches and their ports.

At the same time, provide setup states and messages for ports and
switches as it is done for the trees.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 12:37:06 -07:00
Vivien Didelot
b96ddf254b net: dsa: use ports list in dsa_to_port
Use the new ports list instead of accessing the dsa_switch array
of ports in the dsa_to_port helper.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 12:37:06 -07:00
Vivien Didelot
ab8ccae122 net: dsa: add ports list in the switch fabric
Add a list of switch ports within the switch fabric. This will help the
lookup of a port inside the whole fabric, and it is the first step
towards supporting multiple CPU ports, before deprecating the usage of
the unique dst->cpu_dp pointer.

In preparation for a future allocation of the dsa_port structures,
return -ENOMEM in case no structure is returned, even though this
error cannot be reached yet.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 12:37:06 -07:00
Vivien Didelot
68bb8ea8ad net: dsa: use dsa_to_port helper everywhere
Do not let the drivers access the ds->ports static array directly
while there is a dsa_to_port helper for this purpose.

At the same time, un-const this helper since the SJA1105 driver
assigns the priv member of the returned dsa_port structure.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 12:37:06 -07:00
Vladimir Oltean
37048e94a2 net: dsa: Remove unused __DSA_SKB_CB macro
The struct __dsa_skb_cb is supposed to span the entire 48-byte skb
control block, while the struct dsa_skb_cb only the portion of it which
is used by the DSA core (the rest is available as private data to
drivers).

The DSA_SKB_CB and __DSA_SKB_CB helpers are supposed to help retrieve
this pointer based on a skb, but it turns out there is nobody directly
interested in the struct __dsa_skb_cb in the kernel. So remove it.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-02 14:17:11 -07:00
Vladimir Oltean
47d23af292 net: dsa: Pass ndo_setup_tc slave callback to drivers
DSA currently handles shared block filters (for the classifier-action
qdisc) in the core due to what I believe are simply pragmatic reasons -
hiding the complexity from drivers and offerring a simple API for port
mirroring.

Extend the dsa_slave_setup_tc function by passing all other qdisc
offloads to the driver layer, where the driver may choose what it
implements and how. DSA is simply a pass-through in this case.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-16 21:32:57 +02:00
Vivien Didelot
e65d45cc35 net: dsa: remove bitmap operations
The bitmap operations were introduced to simplify the switch drivers
in the future, since most of them could implement the common VLAN and
MDB operations (add, del, dump) with simple functions taking all target
ports at once, and thus limiting the number of hardware accesses.

Programming an MDB or VLAN this way in a single operation would clearly
simplify the drivers a lot but would require a new get-set interface
in DSA. The usage of such bitmap from the stack also raised concerned
in the past, leading to the dynamic allocation of a new ds->_bitmap
member in the dsa_switch structure. So let's get rid of them for now.

This commit nicely wraps the ds->ops->port_{mdb,vlan}_{prepare,add}
switch operations into new dsa_switch_{mdb,vlan}_{prepare,add}
variants not using any bitmap argument anymore.

New dsa_switch_{mdb,vlan}_match helpers have been introduced to make
clear which local port of a switch must be programmed with the target
object. While the targeted user port is an obvious candidate, the
DSA links must also be programmed, as well as the CPU port for VLANs.

While at it, also remove local variables that are only used once.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-27 20:17:27 -07:00
Tristram Ha
016e43a26b net: dsa: ksz: Add KSZ8795 tag code
Add DSA tag code for Microchip KSZ8795 switch. The switch is simpler
and the tag is only 1 byte, instead of 2 as is the case with KSZ9477.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: David S. Miller <davem@davemloft.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Tristram Ha <Tristram.Ha@microchip.com>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-30 15:12:50 -07:00
Vivien Didelot
68b2d4a844 net: dsa: make cpu_dp non const
A port may trigger operations on its dedicated CPU port, so using
cpu_dp as const will raise warnings. Make cpu_dp non const.

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>
2019-06-14 20:20:07 -07:00
Vladimir Oltean
5e3f847a02 net: dsa: Add teardown callback for drivers
This is helpful for e.g. draining per-driver (not per-port) tagger
queues.

Signed-off-by: Vladimir Oltean <olteanv@gmail.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>
2019-06-08 15:20:39 -07:00
David S. Miller
a6cdeeb16b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 11:00:14 -07:00
Thomas Gleixner
2874c5fd28 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>
2019-05-30 11:26:32 -07:00
Ioana Ciornei
44cc27e43f net: phylink: Add struct phylink_config to PHYLINK API
The phylink_config structure will encapsulate a pointer to a struct
device and the operation type requested for this instance of PHYLINK.
This patch does not make any functional changes, it just transitions the
PHYLINK internals and all its users to the new API.

A pointer to a phylink_config structure will be passed to
phylink_create() instead of the net_device directly. Also, the same
phylink_config pointer will be passed back to all phylink_mac_ops
callbacks instead of the net_device. Using this mechanism, a PHYLINK
user can get the original net_device using a structure such as
'to_net_dev(config->dev)' or directly the structure containing the
phylink_config using a container_of call.

At the moment, only the PHYLINK_NETDEV is defined as a valid operation
type for PHYLINK. In this mode, a valid reference to a struct device
linked to the original net_device should be passed to PHYLINK through
the phylink_config structure.

This API changes is mainly driven by the necessity of adding a new
operation type in PHYLINK that disconnects the phy_device from the
net_device and also works when the net_device is lacking.

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>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-29 21:48:53 -07:00
Vladimir Oltean
1c9b1420ac net: dsa: Remove the now unused DSA_SKB_CB_COPY() macro
It's best to not expose this, due to the performance hit it may cause
when calling it.

Fixes: b68b0dd0fb ("net: dsa: Keep private info in the skb->cb")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-12 13:19:46 -07:00
Vladimir Oltean
506f0e09ce net: dsa: Remove dangerous DSA_SKB_CLONE() macro
This does not cause any bug now because it has no users, but its body
contains two pointer definitions within a code block:

		struct sk_buff *clone = _clone;	\
		struct sk_buff *skb = _skb;	\

When calling the macro as DSA_SKB_CLONE(clone, skb), these variables
would obscure the arguments that the macro was called with, and the
initializers would be a no-op instead of doing their job (undefined
behavior, by the way, but GCC nicely puts NULL pointers instead).

So simply remove this broken macro and leave users to simply call
"DSA_SKB_CB(skb)->clone = clone" by hand when needed.

There is one functional difference when doing what I just suggested
above: the control block won't be transferred from the original skb into
the clone. Since there's no foreseen need for the control block in the
clone ATM, this is ok.

Fixes: b68b0dd0fb ("net: dsa: Keep private info in the skb->cb")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-12 13:19:46 -07:00
Vladimir Oltean
8767137510 net: dsa: Initialize DSA_SKB_CB(skb)->deferred_xmit variable
The sk_buff control block can have any contents on xmit put there by the
stack, so initialization is mandatory, since we are checking its value
after the actual DSA xmit (the tagger may have changed it).

The DSA_SKB_ZERO() macro could have been used for this purpose, but:
- Zeroizing a 48-byte memory region in the hotpath is best avoided.
- It would have triggered a warning with newer compilers since
  __dsa_skb_cb contains a structure within a structure, and the {0}
  initializer was incorrect for that purpose.

So simply remove the DSA_SKB_ZERO() macro and initialize the
deferred_xmit variable by hand (which should be done for all further
dsa_skb_cb variables which need initialization - currently none - to
avoid the performance penalty).

Fixes: 97a69a0dea ("net: dsa: Add support for deferred xmit")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-12 13:19:46 -07:00
Vladimir Oltean
227d07a07e net: dsa: sja1105: Add support for traffic through standalone ports
In order to support this, we are creating a make-shift switch tag out of
a VLAN trunk configured on the CPU port. Termination of normal traffic
on switch ports only works when not under a vlan_filtering bridge.
Termination of management (PTP, BPDU) traffic works under all
circumstances because it uses a different tagging mechanism
(incl_srcpt). We are making use of the generic CONFIG_NET_DSA_TAG_8021Q
code and leveraging it from our own CONFIG_NET_DSA_TAG_SJA1105.

There are two types of traffic: regular and link-local.

The link-local traffic received on the CPU port is trapped from the
switch's regular forwarding decisions because it matched one of the two
DMAC filters for management traffic.

On transmission, the switch requires special massaging for these
link-local frames. Due to a weird implementation of the switching IP, by
default it drops link-local frames that originate on the CPU port.
It needs to be told where to forward them to, through an SPI command
("management route") that is valid for only a single frame.
So when we're sending link-local traffic, we are using the
dsa_defer_xmit mechanism.

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>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
c362beb072 net: dsa: Add a private structure pointer to dsa_port
This is supposed to share information between the driver and the tagger,
or used by the tagger to keep some state. Its use is optional.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
97a69a0dea net: dsa: Add support for deferred xmit
Some hardware needs to take work to get convinced to receive frames on
the CPU port (such as the sja1105 which takes temporary L2 forwarding
rules over SPI that last for a single frame). Such work needs a
sleepable context, and because the regular .ndo_start_xmit is atomic,
this cannot be done in the tagger. So introduce a generic DSA mechanism
that sets up a transmit skb queue and a workqueue for deferred
transmission.

The new driver callback (.port_deferred_xmit) is in dsa_switch and not
in the tagger because the operations that require sleeping typically
also involve interacting with the hardware, and not simply skb
manipulations. Therefore having it there simplifies the structure a bit
and makes it unnecessary to export functions from the driver to the
tagger.

The driver is responsible of calling dsa_enqueue_skb which transfers it
to the master netdevice. This is so that it has a chance of performing
some more work afterwards, such as cleanup or TX timestamping.

To tell DSA that skb xmit deferral is required, I have thought about
changing the return type of the tagger .xmit from struct sk_buff * into
a enum dsa_tx_t that could potentially encode a DSA_XMIT_DEFER value.

But the trailer tagger is reallocating every skb on xmit and therefore
making a valid use of the pointer return value. So instead of reworking
the API in complicated ways, right now a boolean property in the newly
introduced DSA_SKB_CB is set.

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>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
b68b0dd0fb net: dsa: Keep private info in the skb->cb
Map a DSA structure over the 48-byte control block that will hold
skb info on transmit and receive. This is only for use within the DSA
processing layer (e.g. communicating between DSA core and tagger) and
not for passing info around with other layers such as the master net
device.

Also add a DSA_SKB_CB_PRIV() macro which retrieves a pointer to the
space up to 48 bytes that the DSA structure does not use. This space can
be used for drivers to add their own private info.

One use is for the PTP timestamping code path. When cloning a skb,
annotate the original with a pointer to the clone, which the driver can
then find easily and place the timestamp to. This avoids the need of a
separate queue to hold clones and a way to match an original to a cloned
skb.

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>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
cc1939e4b3 net: dsa: Allow drivers to filter packets they can decode source port from
Frames get processed by DSA and redirected to switch port net devices
based on the ETH_P_XDSA multiplexed packet_type handler found by the
network stack when calling eth_type_trans().

The running assumption is that once the DSA .rcv function is called, DSA
is always able to decode the switch tag in order to change the skb->dev
from its master.

However there are tagging protocols (such as the new DSA_TAG_PROTO_SJA1105,
user of DSA_TAG_PROTO_8021Q) where this assumption is not completely
true, since switch tagging piggybacks on the absence of a vlan_filtering
bridge. Moreover, management traffic (BPDU, PTP) for this switch doesn't
rely on switch tagging, but on a different mechanism. So it would make
sense to at least be able to terminate that.

Having DSA receive traffic it can't decode would put it in an impossible
situation: the eth_type_trans() function would invoke the DSA .rcv(),
which could not change skb->dev, then eth_type_trans() would be invoked
again, which again would call the DSA .rcv, and the packet would never
be able to exit the DSA filter and would spiral in a loop until the
whole system dies.

This happens because eth_type_trans() doesn't actually look at the skb
(so as to identify a potential tag) when it deems it as being
ETH_P_XDSA. It just checks whether skb->dev has a DSA private pointer
installed (therefore it's a DSA master) and that there exists a .rcv
callback (everybody except DSA_TAG_PROTO_NONE has that). This is
understandable as there are many switch tags out there, and exhaustively
checking for all of them is far from ideal.

The solution lies in introducing a filtering function for each tagging
protocol. In the absence of a filtering function, all traffic is passed
to the .rcv DSA callback. The tagging protocol should see the filtering
function as a pre-validation that it can decode the incoming skb. The
traffic that doesn't match the filter will bypass the DSA .rcv callback
and be left on the master netdevice, which wasn't previously possible.

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>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
f9bbe4477c net: dsa: Optional VLAN-based port separation for switches without tagging
This patch provides generic DSA code for using VLAN (802.1Q) tags for
the same purpose as a dedicated switch tag for injection/extraction.
It is based on the discussions and interest that has been so far
expressed in https://www.spinics.net/lists/netdev/msg556125.html.

Unlike all other DSA-supported tagging protocols, CONFIG_NET_DSA_TAG_8021Q
does not offer a complete solution for drivers (nor can it). Instead, it
provides generic code that driver can opt into calling:
- dsa_8021q_xmit: Inserts a VLAN header with the specified contents.
  Can be called from another tagging protocol's xmit function.
  Currently the LAN9303 driver is inserting headers that are simply
  802.1Q with custom fields, so this is an opportunity for code reuse.
- dsa_8021q_rcv: Retrieves the TPID and TCI from a VLAN-tagged skb.
  Removing the VLAN header is left as a decision for the caller to make.
- dsa_port_setup_8021q_tagging: For each user port, installs an Rx VID
  and a Tx VID, for proper untagged traffic identification on ingress
  and steering on egress. Also sets up the VLAN trunk on the upstream
  (CPU or DSA) port. Drivers are intentionally left to call this
  function explicitly, depending on the context and hardware support.
  The expected switch behavior and VLAN semantics should not be violated
  under any conditions. That is, after calling
  dsa_port_setup_8021q_tagging, the hardware should still pass all
  ingress traffic, be it tagged or untagged.

For uniformity with the other tagging protocols, a module for the
dsa_8021q_netdev_ops structure is registered, but the typical usage is
to set up another tagging protocol which selects CONFIG_NET_DSA_TAG_8021Q,
and calls the API from tag_8021q.h. Null function definitions are also
provided so that a "depends on" is not forced in the Kconfig.

This tagging protocol only works when switch ports are standalone, or
when they are added to a VLAN-unaware bridge. It will probably remain
this way for the reasons below.

When added to a bridge that has vlan_filtering 1, the bridge core will
install its own VLANs and reset the pvids through switchdev. For the
bridge core, switchdev is a write-only pipe. All VLAN-related state is
kept in the bridge core and nothing is read from DSA/switchdev or from
the driver. So the bridge core will break this port separation because
it will install the vlan_default_pvid into all switchdev ports.

Even if we could teach the bridge driver about switchdev preference of a
certain vlan_default_pvid (task difficult in itself since the current
setting is per-bridge but we would need it per-port), there would still
exist many other challenges.

Firstly, in the DSA rcv callback, a driver would have to perform an
iterative reverse lookup to find the correct switch port. That is
because the port is a bridge slave, so its Rx VID (port PVID) is subject
to user configuration. How would we ensure that the user doesn't reset
the pvid to a different value (which would make an O(1) translation
impossible), or to a non-unique value within this DSA switch tree (which
would make any translation impossible)?

Finally, not all switch ports are equal in DSA, and that makes it
difficult for the bridge to be completely aware of this anyway.
The CPU port needs to transmit tagged packets (VLAN trunk) in order for
the DSA rcv code to be able to decode source information.
But the bridge code has absolutely no idea which switch port is the CPU
port, if nothing else then just because there is no netdevice registered
by DSA for the CPU port.
Also DSA does not currently allow the user to specify that they want the
CPU port to do VLAN trunking anyway. VLANs are added to the CPU port
using the same flags as they were added on the user port.

So the VLANs installed by dsa_port_setup_8021q_tagging per driver
request should remain private from the bridge's and user's perspective,
and should not alter the VLAN semantics observed by the user.

In the current implementation a VLAN range ending at 4095 (VLAN_N_VID)
is reserved for this purpose. Each port receives a unique Rx VLAN and a
unique Tx VLAN. Separate VLANs are needed for Rx and Tx because they
serve different purposes: on Rx the switch must process traffic as
untagged and process it with a port-based VLAN, but with care not to
hinder bridging. On the other hand, the Tx VLAN is where the
reachability restrictions are imposed, since by tagging frames in the
xmit callback we are telling the switch onto which port to steer the
frame.

Some general guidance on how this support might be employed for
real-life hardware (some comments made by Florian Fainelli):

- If the hardware supports VLAN tag stacking, it should somehow back
  up its private VLAN settings when the bridge tries to override them.
  Then the driver could re-apply them as outer tags. Dedicating an outer
  tag per bridge device would allow identical inner tag VID numbers to
  co-exist, yet preserve broadcast domain isolation.

- If the switch cannot handle VLAN tag stacking, it should disable this
  port separation when added as slave to a vlan_filtering bridge, in
  that case having reduced functionality.

- Drivers for old switches that don't support the entire VLAN_N_VID
  range will need to rework the current range selection mechanism.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 21:52:42 -07:00
Andrew Lunn
93e86b3bc8 net: dsa: Remove legacy probing support
Now that all drivers can be probed using more traditional methods,
remove the legacy probe code.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-30 23:15:35 -04:00
Vladimir Oltean
cf2d45f5ba net: dsa: Add helper function to retrieve VLAN awareness setting
Since different types of hardware may or may not support this setting
per-port, DSA keeps it either in dsa_switch or in dsa_port.

While drivers may know the characteristics of their hardware and
retrieve it from the correct place without the need of helpers, it is
cumbersone to find out an unambigous answer from generic DSA code.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-30 23:05:29 -04:00
Vladimir Oltean
145746765f 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>
2019-04-30 23:05:29 -04:00
Vladimir Oltean
8f5d16f638 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>
2019-04-30 23:05:28 -04:00
Vladimir Oltean
33162e9a05 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>
2019-04-30 23:05:28 -04:00
Andrew Lunn
f81a43e8da dsa: Cleanup unneeded table and make tag structures static
Now that tag drivers dynamically register, we don't need the static
table. Remove it. This also means the tag driver structures can be
made static.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28 19:41:01 -04:00
Andrew Lunn
d3b8c04988 dsa: Add boilerplate helper to register DSA tag driver modules
A DSA tag driver module will need to register the tag protocols it
implements with the DSA core. Add macros containing this boiler plate.

The registration/unregistration code is currently just a stub. A Later
patch will add the real implementation.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>

v2
Fix indent of #endif
Rewrite to move list pointer into a new structure
v3
Move kdoc next to macro
Fix THIS_MODULE indentation

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28 19:41:01 -04:00
Andrew Lunn
056eed2fb0 dsa: Add TAG protocol to tag ops
In order that we can match the tagging protocol a switch driver
request to the tagger, we need to know what protocol the tagger
supports. Add this information to the ops structure.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>

v2
More tag protocol to end of structure to keep hot members at the beginning.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28 19:41:01 -04:00
Andrew Lunn
0b42f03363 dsa: Add MODULE_ALIAS to taggers in preparation to become modules
When the tag drivers become modules, we will need to dynamically load
them based on what the switch drivers need. Add aliases to map between
the TAG protocol and the driver.

In order to do this, we need the tag protocol number as something
which the C pre-processor can stringinfy. Only the compiler knows the
value of an enum, CPP cannot use them. So add #defines.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28 19:41:01 -04:00
Andrew Lunn
875138f81d dsa: Move tagger name into its ops structure
Rather than keep a list to map a tagger ops to a name, place the name
into the ops structure. This removes the hard coded list, a step
towards making the taggers more dynamic.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>

v2:
Move name to end of structure, keeping the hot entries at the beginning.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28 19:41:00 -04:00
Xiaofei Shen
a2c7023f70 net: dsa: read mac address from DT for slave device
Before creating a slave netdevice, get the mac address from DTS and
apply in case it is valid.

Signed-off-by: Xiaofei Shen <xiaofeis@codeaurora.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-01 14:57:32 -07:00
Tristram Ha
88b573af91 net: dsa: add KSZ9893 switch tagging support
KSZ9893 switch is similar to KSZ9477 switch except the ingress tail tag
has 1 byte instead of 2 bytes.  The size of the portmap is smaller and
so the override and lookup bits are also moved.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-03 13:48:49 -08:00
Andrew Lunn
75104db0cb 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>
2019-02-24 22:30:34 -08:00