net: fill in MODULE_DESCRIPTION()s for DSA tags

W=1 builds now warn if module is built without a MODULE_DESCRIPTION().
Add descriptions to all the DSA tag modules.

The descriptions are copy/pasted Kconfig names, with s/^Tag/DSA tag/.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Acked-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Acked-by: Kurt Kanzenbach <kurt@linutronix.de>
Link: https://lore.kernel.org/r/20240104143759.1318137-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: Use conduit and user terms

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

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

net: dsa: move tagging protocol code to tag.{c,h}

It would be nice if tagging protocol drivers could include just the
header they need, since they are (mostly) data path and isolated from
most of the other DSA core code does.

Create a tag.c and a tag.h file which are meant to support tagging
protocol drivers.

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

net: dsa: provide a second modalias to tag proto drivers based on their name

Currently, tagging protocol drivers have a modalias of
"dsa_tag:id-<number>", where the number is one of DSA_TAG_PROTO_*_VALUE.

This modalias makes it possible for the request_module() call in
dsa_tag_driver_get() to work, given the input it has - an integer
returned by ds->ops->get_tag_protocol().

It is also possible to change tagging protocols at (pseudo-)runtime, via
sysfs or via device tree, and this works via the name string of the
tagging protocol rather than via its id (DSA_TAG_PROTO_*_VALUE).

In the latter case, there is no request_module() call, because there is
no association that the DSA core has between the string name and the ID,
to construct the modalias. The module is simply assumed to have been
inserted. This is actually slightly problematic when the tagging
protocol change should take place at probe time, since it's expected
that the dependency module should get autoloaded.

For this purpose, let's introduce a second modalias, so that the DSA
core can call request_module() by name. There is no reason to make the
modalias by name optional, so just modify the MODULE_ALIAS_DSA_TAG_DRIVER()
macro to take both the ID and the name as arguments, and generate two
modaliases behind the scenes.

Suggested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc> # on kontron-sl28 w/ ocelot_8021q
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: tag_dsa: Fix tx from VLAN uppers on non-filtering bridges

In this situation (VLAN filtering disabled on br0):

br0.10
/
br0
/ \
swp0 swp1

When a frame is transmitted from the VLAN upper, the bridge will send
it down to one of the switch ports with forward offloading
enabled. This will cause tag_dsa to generate a FORWARD tag. Before
this change, that tag would have it's VID set to 10, even though VID
10 is not loaded in the VTU.

Before the blamed commit, the frame would trigger a VTU miss and be
forwarded according to the PVT configuration. Now that all fabric
ports are in 802.1Q secure mode, the frame is dropped instead.

Therefore, restrict the condition under which we rewrite an 802.1Q tag
to a DSA tag. On standalone port's, reuse is always safe since we will
always generate FROM_CPU tags in that case. For bridged ports though,
we must ensure that VLAN filtering is enabled, which in turn
guarantees that the VID in question is loaded into the VTU.

Fixes: d352b20f4174 ("net: dsa: mv88e6xxx: Improve multichip isolation of standalone ports")
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20220307110548.812455-1-tobias@waldekranz.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: create a dsa_lag structure

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

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

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

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

dsa_lag_foreach_port() now takes the dsa_lag structure as argument.

dst->lags holds an array of dsa_lag structures.

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

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

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

net: dsa: make LAG IDs one-based

The DSA LAG API will be changed to become more similar with the bridge
data structures, where struct dsa_bridge holds an unsigned int num,
which is generated by DSA and is one-based. We have a similar thing
going with the DSA LAG, except that isn't stored anywhere, it is
calculated dynamically by dsa_lag_id() by iterating through dst->lags.

The idea of encoding an invalid (or not requested) LAG ID as zero for
the purpose of simplifying checks in drivers means that the LAG IDs
passed by DSA to drivers need to be one-based too. So back-and-forth
conversion is needed when indexing the dst->lags array, as well as in
drivers which assume a zero-based index.

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

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

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

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

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

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

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

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

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

net: dsa: mv88e6xxx: isolate the ATU databases of standalone and bridged ports

Similar to commit 6087175b7991 ("net: dsa: mt7530: use independent VLAN
learning on VLAN-unaware bridges"), software forwarding between an
unoffloaded LAG port (a bonding interface with an unsupported policy)
and a mv88e6xxx user port directly under a bridge is broken.

We adopt the same strategy, which is to make the standalone ports not
find any ATU entry learned on a bridge port.

Theory: the mv88e6xxx ATU is looked up by FID and MAC address. There are
as many FIDs as VIDs (4096). The FID is derived from the VID when
possible (the VTU maps a VID to a FID), with a fallback to the port
based default FID value when not (802.1Q Mode is disabled on the port,
or the classified VID isn't present in the VTU).

The mv88e6xxx driver makes the following use of FIDs and VIDs:

- the port's DefaultVID (to which untagged & pvid-tagged packets get
classified) is 0 and is absent from the VTU, so this kind of packets is
processed in FID 0, the default FID assigned by mv88e6xxx_setup_port.

- every time a bridge VLAN is created, mv88e6xxx_port_vlan_join() ->
mv88e6xxx_atu_new() associates a FID with that VID which increases
linearly starting from 1. Like this:

bridge vlan add dev lan0 vid 100 # FID 1
bridge vlan add dev lan1 vid 100 # still FID 1
bridge vlan add dev lan2 vid 1024 # FID 2

The FID allocation made by the driver is sub-optimal for the following
reasons:

(a) A standalone port has a DefaultPVID of 0 and a default FID of 0 too.
A VLAN-unaware bridged port has a DefaultPVID of 0 and a default FID
of 0 too. The difference is that the bridged ports may learn ATU
entries, while the standalone port has the requirement that it must
not, and must not find them either. Standalone ports must not use
the same FID as ports belonging to a bridge. All standalone ports
can use the same FID, since the ATU will never have an entry in
that FID.

(b) Multiple VLAN-unaware bridges will all use a DefaultPVID of 0 and a
default FID of 0 on all their ports. The FDBs will not be isolated
between these bridges. Every VLAN-unaware bridge must use the same
FID on all its ports, different from the FID of other bridge ports.

(c) Each bridge VLAN uses a unique FID which is useful for Independent
VLAN Learning, but the same VLAN ID on multiple VLAN-aware bridges
will result in the same FID being used by mv88e6xxx_atu_new().
The correct behavior is for VLAN 1 in br0 to have a different FID
compared to VLAN 1 in br1.

This patch cannot fix all the above. Traditionally the DSA framework did
not care about this, and the reality is that DSA core involvement is
needed for the aforementioned issues to be solved. The only thing we can
solve here is an issue which does not require API changes, and that is
issue (a), aka use a different FID for standalone ports vs ports under
VLAN-unaware bridges.

The first step is deciding what VID and FID to use for standalone ports,
and what VID and FID for bridged ports. The 0/0 pair for standalone
ports is what they used up till now, let's keep using that. For bridged
ports, there are 2 cases:

- VLAN-aware ports will never end up using the port default FID, because
packets will always be classified to a VID in the VTU or dropped
otherwise. The FID is the one associated with the VID in the VTU.

- On VLAN-unaware ports, we _could_ leave their DefaultVID (pvid) at
zero (just as in the case of standalone ports), and just change the
port's default FID from 0 to a different number (say 1).

However, Tobias points out that there is one more requirement to cater to:
cross-chip bridging. The Marvell DSA header does not carry the FID in
it, only the VID. So once a packet crosses a DSA link, if it has a VID
of zero it will get classified to the default FID of that cascade port.
Relying on a port default FID for upstream cascade ports results in
contradictions: a default FID of 0 breaks ATU isolation of bridged ports
on the downstream switch, a default FID of 1 breaks standalone ports on
the downstream switch.

So not only must standalone ports have different FIDs compared to
bridged ports, they must also have different DefaultVID values.
IEEE 802.1Q defines two reserved VID values: 0 and 4095. So we simply
choose 4095 as the DefaultVID of ports belonging to VLAN-unaware
bridges, and VID 4095 maps to FID 1.

For the xmit operation to look up the same ATU database, we need to put
VID 4095 in DSA tags sent to ports belonging to VLAN-unaware bridges
too. All shared ports are configured to map this VID to the bridging
FID, because they are members of that VLAN in the VTU. Shared ports
don't need to have 802.1QMode enabled in any way, they always parse the
VID from the DSA header, they don't need to look at the 802.1Q header.

We install VID 4095 to the VTU in mv88e6xxx_setup_port(), with the
mention that mv88e6xxx_vtu_setup() which was located right below that
call was flushing the VTU so those entries wouldn't be preserved.
So we need to relocate the VTU flushing prior to the port initialization
during ->setup(). Also note that this is why it is safe to assume that
VID 4095 will get associated with FID 1: the user ports haven't been
created, so there is no avenue for the user to create a bridge VLAN
which could otherwise race with the creation of another FID which would
otherwise use up the non-reserved FID value of 1.

[ Currently mv88e6xxx_port_vlan_join() doesn't have the option of
specifying a preferred FID, it always calls mv88e6xxx_atu_new(). ]

mv88e6xxx_port_db_load_purge() is the function to access the ATU for
FDB/MDB entries, and it used to determine the FID to use for
VLAN-unaware FDB entries (VID=0) using mv88e6xxx_port_get_fid().
But the driver only called mv88e6xxx_port_set_fid() once, during probe,
so no surprises, the port FID was always 0, the call to get_fid() was
redundant. As much as I would have wanted to not touch that code, the
logic is broken when we add a new FID which is not the port-based
default. Now the port-based default FID only corresponds to standalone
ports, and FDB/MDB entries belong to the bridging service. So while in
the future, when the DSA API will support FDB isolation, we will have to
figure out the FID based on the bridge number, for now there's a single
bridging FID, so hardcode that.

Lastly, the tagger needs to check, when it is transmitting a VLAN
untagged skb, whether it is sending it towards a bridged or a standalone
port. When we see it is bridged we assume the bridge is VLAN-unaware.
Not because it cannot be VLAN-aware but:

- if we are transmitting from a VLAN-aware bridge we are likely doing so
using TX forwarding offload. That code path guarantees that skbs have
a vlan hwaccel tag in them, so we would not enter the "else" branch
of the "if (skb->protocol == htons(ETH_P_8021Q))" condition.

- if we are transmitting on behalf of a VLAN-aware bridge but with no TX
forwarding offload (no PVT support, out of space in the PVT, whatever),
we would indeed be transmitting with VLAN 4095 instead of the bridge
device's pvid. However we would be injecting a "From CPU" frame, and
the switch won't learn from that - it only learns from "Forward" frames.
So it is inconsequential for address learning. And VLAN 4095 is
absolutely enough for the frame to exit the switch, since we never
remove that VLAN from any port.

Fixes: 57e661aae6a8 ("net: dsa: mv88e6xxx: Link aggregation support")
Reported-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: tag_dsa: send packets with TX fwd offload from VLAN-unaware bridges using VID 0

The present code is structured this way due to an incomplete thought
process. In Documentation/networking/switchdev.rst we document that if a
bridge is VLAN-unaware, then the presence or lack of a pvid on a bridge
port (or on the bridge itself, for that matter) should not affect the
ability to receive and transmit tagged or untagged packets.

If the bridge on behalf of which we are sending this packet is
VLAN-aware, then the TX forwarding offload API ensures that the skb will
be VLAN-tagged (if the packet was sent by user space as untagged, it
will get transmitted town to the driver as tagged with the bridge
device's pvid). But if the bridge is VLAN-unaware, it may or may not be
VLAN-tagged. In fact the logic to insert the bridge's PVID came from the
idea that we should emulate what is being done in the VLAN-aware case.
But we shouldn't.

It appears that injecting packets using a VLAN ID of 0 serves the
purpose of forwarding the packets to the egress port with no VLAN tag
added or stripped by the hardware, and no filtering being performed.
So we can simply remove the superfluous logic.

One reason why this logic is broken is that when CONFIG_BRIDGE_VLAN_FILTERING=n,
we call br_vlan_get_pvid_rcu() but that returns an error and we do error
out, dropping all packets on xmit. Not really smart. This is also an
issue when the user deletes the bridge pvid:

$ bridge vlan del dev br0 vid 1 self

As mentioned, in both cases, packets should still flow freely, and they
do just that on any net device where the bridge is not offloaded, but on
mv88e6xxx they don't.

Fixes: d82f8ab0d874 ("net: dsa: tag_dsa: offload the bridge forwarding process")
Reported-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20211003155141.2241314-1-andrew@lunn.ch/
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20210928233708.1246774-1-vladimir.oltean@nxp.com/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

dsa: tag_dsa: Fix mask for trunked packets

A packet received on a trunk will have bit 2 set in Forward DSA tagged
frame. Bit 1 can be either 0 or 1 and is otherwise undefined and bit 0
indicates the frame CFI. Masking with 7 thus results in frames as
being identified as being from a trunk when in fact they are not. Fix
the mask to just look at bit 2.

Fixes: 5b60dadb71db ("net: dsa: tag_dsa: Support reception of packets from LAG devices")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: create a helper for locating EtherType DSA headers on TX

Create a similar helper for locating the offset to the DSA header
relative to skb->data, and make the existing EtherType header taggers to
use it.

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

net: dsa: create a helper for locating EtherType DSA headers on RX

It seems that protocol tagging driver writers are always surprised about
the formula they use to reach their EtherType header on RX, which
becomes apparent from the fact that there are comments in multiple
drivers that mention the same information.

Create a helper that returns a void pointer to skb->data - 2, as well as
centralize the explanation why that is the case.

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

net: dsa: create a helper which allocates space for EtherType DSA headers

Hide away the memmove used by DSA EtherType header taggers to shift the
MAC SA and DA to the left to make room for the header, after they've
called skb_push(). The call to skb_push() is still left explicit in
drivers, to be symmetric with dsa_strip_etype_header, and because not
all callers can be refactored to do it (for example, brcm_tag_xmit_ll
has common code for a pre-Ethernet DSA tag and an EtherType DSA tag).

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

net: dsa: create a helper that strips EtherType DSA headers on RX

All header taggers open-code a memmove that is fairly not all that
obvious, and we can hide the details behind a helper function, since the
only thing specific to the driver is the length of the header tag.

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

net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv()

No tagging driver uses this.

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

net: dsa: don't set skb->offload_fwd_mark when not offloading the bridge

DSA has gained the recent ability to deal gracefully with upper
interfaces it cannot offload, such as the bridge, bonding or team
drivers. When such uppers exist, the ports are still in standalone mode
as far as the hardware is concerned.

But when we deliver packets to the software bridge in order for that to
do the forwarding, there is an unpleasant surprise in that the bridge
will refuse to forward them. This is because we unconditionally set
skb->offload_fwd_mark = true, meaning that the bridge thinks the frames
were already forwarded in hardware by us.

Since dp->bridge_dev is populated only when there is hardware offload
for it, but not in the software fallback case, let's introduce a new
helper that can be called from the tagger data path which sets the
skb->offload_fwd_mark accordingly to zero when there is no hardware
offload for bridging. This lets the bridge forward packets back to other
interfaces of our switch, if needed.

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

net: dsa: tag_dsa: offload the bridge forwarding process

Allow the DSA tagger to generate FORWARD frames for offloaded skbs
sent from a bridge that we offload, allowing the switch to handle any
frame replication that may be required. This also means that source
address learning takes place on packets sent from the CPU, meaning
that return traffic no longer needs to be flooded as unknown unicast.

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

net: dsa: generalize overhead for taggers that use both headers and trailers

Some really really weird switches just couldn't decide whether to use a
normal or a tail tagger, so they just did both.

This creates problems for DSA, because we only have the concept of an
'overhead' which can be applied to the headroom or to the tailroom of
the skb (like for example during the central TX reallocation procedure),
depending on the value of bool tail_tag, but not to both.

We need to generalize DSA to cater for these odd switches by
transforming the 'overhead / tail_tag' pair into 'needed_headroom /
needed_tailroom'.

The DSA master's MTU is increased to account for both.

The flow dissector code is modified such that it only calls the DSA
adjustment callback if the tagger has a non-zero header length.

Taggers are trivially modified to declare either needed_headroom or
needed_tailroom, based on the tail_tag value that they currently
declare.

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

net: dsa: tag_dsa: Support reception of packets from LAG devices

Packets ingressing on a LAG that egress on the CPU port, which are not
classified as management, will have a FORWARD tag that does not
contain the normal source device/port tuple. Instead the trunk bit
will be set, and the port field holds the LAG id.

Since the exact source port information is not available in the tag,
frames are injected directly on the LAG interface and thus do never
pass through any DSA port interface on ingress.

Management frames (TO_CPU) are not affected and will pass through the
DSA port interface as usual.

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

net: dsa: tag_dsa: Use a consistent comment style

Use a consistent style of one-line/multi-line comments throughout the
file.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: tag_dsa: Unify regular and ethertype DSA taggers

Ethertype DSA encodes exactly the same information in the DSA tag as
the non-ethertype variety. So refactor out the common parts and reuse
them for both protocols.

This is ensures tag parsing and generation is always consistent across
all mv88e6xxx chips.

While we are at it, explicitly deal with all possible CPU codes on
receive, making sure to set offload_fwd_mark as appropriate.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: tag_dsa: Allow forwarding of redirected IGMP traffic

When receiving an IGMP/MLD frame with a TO_CPU tag, the switch has not
performed any forwarding of it. This means that we should not set the
offload_fwd_mark on the skb, in case a software bridge wants it
forwarded.

This is a port of:

1ed9ec9b08ad ("dsa: Allow forwarding of redirected IGMP traffic")

Which corrected the issue for chips using EDSA tags, but not for those
using regular DSA tags.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: tag_dsa: let DSA core deal with TX reallocation

Now that we have a central TX reallocation procedure that accounts for
the tagger's needed headroom in a generic way, we can remove the
skb_cow_head call.

Similar to the EtherType DSA tagger, the old Marvell tagger can
transform an 802.1Q header if present into a DSA tag, so there is no
headroom required in that case. But we are ensuring that it exists,
regardless (practically speaking, the headroom must be 4 bytes larger
than it needs to be).

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

net: dsa: tag_dsa: use the generic flow dissector procedure

Remove the .flow_dissect procedure, so the flow dissector will call the
generic variant which works for this tagging protocol.

Cc: Andrew Lunn <andrew@lunn.ch>
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>

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>

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>

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>

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>

dsa: Add MODULE_LICENSE to tag drivers

All the tag drivers are some variant of GPL. Add a MODULE_LICENSE()
indicating this, so the drivers can later be compiled as modules.

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>

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>

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>

dsa: Add SPDX header to tag drivers.

Add an SPDX header, and remove the license boilerplate text.

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>

net: dsa: Implement flow_dissect callback for tag_dsa.

RPS not work for DSA devices since the 'skb_get_hash'
will always get the invalid hash for dsa tagged packets.

"[PATCH] tag_mtk: add flow_dissect callback to the ops struct"
introduced the flow_dissect callback to get the right hash for
MTK tagged packet. Tag_dsa and tag_edsa also need to implement
the callback.

Signed-off-by: Rundong Ge <rdong.ge@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Add overhead to tag protocol ops.

Each DSA tag protocol needs to add additional headers to the Ethernet
frame in order to direct it towards a specific switch egress port. It
must also remove the head from a frame received from a
switch. Indicate the maximum size of these headers in the tag protocol
ops structure, so the core can take these overheads into account.

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

net: dsa: {e}dsa: set offload_fwd_mark on received packets

The software bridge needs to know if a packet has already been bridged
by hardware offload to ports in the same hardware offload, in order
that it does not re-flood them, causing duplicates. This is
particularly true for broadcast and multicast traffic which the host
has requested.

By setting offload_fwd_mark in the skb the bridge will only flood to
ports in other offloads and other netifs. Set this flag in the DSA and
EDSA tag driver.

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

net: dsa: rename dsa_master_get_slave

The dsa_master_get_slave is slightly confusing since the idiomatic "get"
term often suggests reference counting, in symmetry to "put".

Rename it to dsa_master_find_slave to make the look up operation clear.

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

net: dsa: add slave to port helper

Many portions of DSA core code require to get the dsa_port structure
corresponding to a slave net_device. For this purpose, introduce a
dsa_slave_to_port() helper.

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

net: dsa: add master helper to look up slaves

The DSA tagging code does not need to know about the DSA architecture,
it only needs to return the slave device corresponding to the source
port index (and eventually the source device index for cascade-capable
switches) parsed from the frame received on the master device.

For this purpose, provide an inline dsa_master_get_slave helper which
validates the device and port indexes and look up the slave device.

This makes the tagging rcv functions more concise and robust, and also
makes dsa_get_cpu_port obsolete.

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

dsa: remove unused net_device arg from handlers

compile tested only, but saw no warnings/errors with
allmodconfig build.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: factor skb freeing on xmit

As of a86d8becc3f0 ("net: dsa: Factor bottom tag receive functions"),
the rcv caller frees the original SKB in case or error.

Be symmetric with that and make the xmit caller do the same.

At the same time, fix the checkpatch NULL comparison check:

CHECK: Comparison to NULL could be written "!nskb"
#208: FILE: net/dsa/tag_trailer.c:35:
+ if (nskb == NULL)

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

net: dsa: remove out_drop label in taggers rcv

Many rcv functions from net/dsa/tag_*.c have a useless out_drop goto
label which simply returns NULL. Kill it in favor of the obvious.

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

net: dsa: include dsa.h only once

The public include/net/dsa.h file is meant for DSA drivers, while all
DSA core files share a common private header net/dsa/dsa_priv.h file.

Ensure that dsa_priv.h is the only DSA core file to include net/dsa.h,
and add a new line to separate absolute and relative headers at the same
time.

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

net: dsa: Factor bottom tag receive functions

All DSA tag receive functions do strictly the same thing after they have located
the originating source port from their tag specific protocol:

- push ETH_HLEN bytes
- set pkt_type to PACKET_HOST
- call eth_type_trans()
- bump up counters
- call netif_receive_skb()

Factor all of that into dsa_switch_rcv(). This also makes us return a pointer to
a sk_buff, which makes us symetric with the xmit function.

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

net: dsa: Move skb_unshare() to dsa_switch_rcv()

All DSA tag receive functions need to unshare the skb before mangling it, move
this to the generic dsa_switch_rcv() function which will allow us to make the
tag receive function return their mangled skb without caring about freeing a
NULL skb.

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

net: dsa: Do not check for NULL dst in tag parsers

dsa_switch_rcv() already tests for dst == NULL, so there is no need to duplicate
the same check within the tag receive functions.

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

net: break include loop netdevice.h, dsa.h, devlink.h

There is an include loop between netdevice.h, dsa.h, devlink.h because
of NETDEV_ALIGN, making it impossible to use devlink structures in
dsa.h.

Break this loop by taking dsa.h out of netdevice.h, add a forward
declaration of dsa_switch_tree and netdev_set_default_ethtool_ops()
function, which is what netdevice.h requires.

No longer having dsa.h in netdevice.h means the includes in dsa.h no
longer get included. This breaks a few other files which depend on
these includes. Add these directly in the affected file.

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>

net: dsa: store a dsa_port in dsa_slave_priv

Store a pointer to the dsa_port structure in the dsa_slave_priv
structure, instead of the switch/port index.

This will allow to store more information such as the bridge device,
needed in DSA drivers for multi-chip configuration.

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

net: dsa: use ds->num_ports when possible

The dsa_switch structure contains the number of ports. Use it where the
structure is valid instead of the DSA_MAX_PORTS value.

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

net: dsa: Add a ports structure and use it in the switch structure

There are going to be more per-port members added to the switch
structure. So add a port structure and move the netdev into it.

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

net: dsa: tag_{e}dsa.c: Remove dependency on platform data

The platform data nr_chips is used when validating a received packet,
to ensure it comes from a know switch chip. The number of possible
switches is limited to DSA_MAX_SWITCHES, so use this as the first
validation step. The new binding allows holes in the dst->ds[] array,
so also ensure ensure there is a valid dsa_switch for this packet.

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

net: dsa: Refactor transmit path to eliminate duplication

All tagging protocols do the same thing: increment device statistics,
make room for the tag to be inserted, create the tag, invoke the parent
network device transmit function.

In order to prepare for adding netpoll support, which requires the tag
creation, but not using the parent network device transmit function, do
some little refactoring which eliminates duplication between the 4
tagging protocols supported.

We need to return a sk_buff pointer back to the caller because the tag
specific transmit function may have to reallocate the original skb (e.g:
tag_trailer.c) and this is the one we should be transmitting, not the
original sk_buff we were passed.

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

net: dsa: Don't set skb->protocol on outgoing tagged packets

Setting skb->protocol to a private protocol type may result in warning
messages such as
e1000e 0000:00:19.0 em1: checksum_partial proto=dada!

This happens if the L3 protocol is IP or IPv6 and skb->ip_summed is set
to CHECKSUM_PARTIAL. Looking through the code, it appears that changing
skb->protocol for transmitted packets is not necessary and may actually
be harmful. For example, it prevents purposely unmodified (from a DSA
perspective) network drivers from properly setting up their transmit
checksum offload pointers since they inspect skb->protocol to set up the
IPv4 header or IPv6 header pointers. So don't unnecessarily change the
protocol field.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

dsa: Split ops up, and avoid assigning tag_protocol and receive separately

This change addresses several issues.

First, it was possible to set tag_protocol without setting the ops pointer.
To correct that I have reordered things so that rcv is now populated before
we set tag_protocol.

Second, it didn't make much sense to keep setting the device ops each time a
new slave was registered. So by moving the receive portion out into root
switch initialization that issue should be addressed.

Third, I wanted to avoid sending tags if the rcv pointer was not registered
so I changed the tag check to verify if the rcv function pointer is set on
the root tree. If it is then we start sending DSA tagged frames.

Finally I split the device ops pointer in the structures into two spots. I
placed the rcv function pointer in the root switch since this makes it
easiest to access from there, and I placed the xmit function pointer in the
slave for the same reason.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: reduce number of protocol hooks

DSA is currently registering one packet_type function per EtherType it
needs to intercept in the receive path of a DSA-enabled Ethernet device.
Right now we have three of them: trailer, DSA and eDSA, and there might
be more in the future, this will not scale to the addition of new
protocols.

This patch proceeds with adding a new layer of abstraction and two new
functions:

dsa_switch_rcv() which will dispatch into the tag-protocol specific
receive function implemented by net/dsa/tag_*.c

dsa_slave_xmit() which will dispatch into the tag-protocol specific
transmit function implemented by net/dsa/tag_*.c

When we do create the per-port slave network devices, we iterate over
the switch protocol to assign the DSA-specific receive and transmit
operations.

A new fake ethertype value is used: ETH_P_XDSA to illustrate the fact
that this is no longer going to look like ETH_P_DSA or ETH_P_TRAILER
like it used to be.

This allows us to greatly simplify the check in eth_type_trans() and
always override the skb->protocol with ETH_P_XDSA for Ethernet switches
tagged protocol, while also reducing the number repetitive slave
netdevice_ops assignments.

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

dsa: Combine core and tagging code

These files have circular dependencies, so if we make DSA modular then
they must be built into the same module. Therefore, link them
together and merge their respective module init and exit functions.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

netdev: convert pseudo-devices to netdev_tx_t

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dsa: add switch chip cascading support

The initial version of the DSA driver only supported a single switch
chip per network interface, while DSA-capable switch chips can be
interconnected to form a tree of switch chips. This patch adds support
for multiple switch chips on a network interface.

An example topology for a 16-port device with an embedded CPU is as
follows:

+-----+ +--------+ +--------+
| |eth0 10| switch |9 10| switch |
| CPU +----------+ +-------+ |
| | | chip 0 | | chip 1 |
+-----+ +---++---+ +---++---+
|| ||
|| ||
||1000baseT ||1000baseT
||ports 1-8 ||ports 9-16

This requires a couple of interdependent changes in the DSA layer:

- The dsa platform driver data needs to be extended: there is still
only one netdevice per DSA driver instance (eth0 in the example
above), but each of the switch chips in the tree needs its own
mii_bus device pointer, MII management bus address, and port name
array. (include/net/dsa.h) The existing in-tree dsa users need
some small changes to deal with this. (arch/arm)

- The DSA and Ethertype DSA tagging modules need to be extended to
use the DSA device ID field on receive and demultiplex the packet
accordingly, and fill in the DSA device ID field on transmit
according to which switch chip the packet is heading to.
(net/dsa/tag_{dsa,edsa}.c)

- The concept of "CPU port", which is the switch chip port that the
CPU is connected to (port 10 on switch chip 0 in the example), needs
to be extended with the concept of "upstream port", which is the
port on the switch chip that will bring us one hop closer to the CPU
(port 10 for both switch chips in the example above).

- The dsa platform data needs to specify which ports on which switch
chips are links to other switch chips, so that we can enable DSA
tagging mode on them. (For inter-switch links, we always use
non-EtherType DSA tagging, since it has lower overhead. The CPU
link uses dsa or edsa tagging depending on what the 'root' switch
chip supports.) This is done by specifying "dsa" for the given
port in the port array.

- The dsa platform data needs to be extended with information on via
which port to reach any given switch chip from any given switch chip.
This info is specified via the per-switch chip data struct ->rtable[]
array, which gives the nexthop ports for each of the other switches
in the tree.

For the example topology above, the dsa platform data would look
something like this:

static struct dsa_chip_data sw[2] = {
{
.mii_bus = &foo,
.sw_addr = 1,
.port_names[0] = "p1",
.port_names[1] = "p2",
.port_names[2] = "p3",
.port_names[3] = "p4",
.port_names[4] = "p5",
.port_names[5] = "p6",
.port_names[6] = "p7",
.port_names[7] = "p8",
.port_names[9] = "dsa",
.port_names[10] = "cpu",
.rtable = (s8 []){ -1, 9, },
}, {
.mii_bus = &foo,
.sw_addr = 2,
.port_names[0] = "p9",
.port_names[1] = "p10",
.port_names[2] = "p11",
.port_names[3] = "p12",
.port_names[4] = "p13",
.port_names[5] = "p14",
.port_names[6] = "p15",
.port_names[7] = "p16",
.port_names[10] = "dsa",
.rtable = (s8 []){ 10, -1, },
},
},

static struct dsa_platform_data pd = {
.netdev = &foo,
.nr_switches = 2,
.sw = sw,
};

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Gary Thomas <gary@mlbassoc.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: convert usage of packet_type to read_mostly

Protocols that use packet_type can be __read_mostly section for better
locality. Elminate any unnecessary initializations of NULL.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: replace uses of __constant_{endian}

Base versions handle constant folding now.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dsa: fix skb->pkt_type when mac address of slave interface differs

When a dsa slave interface has a mac address that differs from that
of the master interface, eth_type_trans() won't explicitly set
skb->pkt_type back to PACKET_HOST -- we need to do this ourselves
before calling eth_type_trans().

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/: Kill now superfluous ->last_rx stores.

The generic packet receive code takes care of setting
netdev->last_rx when necessary, for the sake of the
bonding ARP monitor.

Signed-off-by: David S. Miller <davem@davemloft.net>

dsa: add support for original DSA tagging format

Most of the DSA switches currently in the field do not support the
Ethertype DSA tagging format that one of the previous patches added
support for, but only the original DSA tagging format.

The original DSA tagging format carries the same information as the
Ethertype DSA tagging format, but with the difference that it does not
have an ethertype field. In other words, when receiving a packet that
is tagged with an original DSA tag, there is no way of telling in
eth_type_trans() that this packet is in fact a DSA-tagged packet.

This patch adds a hook into eth_type_trans() which is only compiled in
if support for a switch chip that doesn't support Ethertype DSA is
selected, and which checks whether there is a DSA switch driver
instance attached to this network device which uses the old tag format.
If so, it sets the protocol field to ETH_P_DSA without looking at the
packet, so that the packet ends up in the right place.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Nicolas Pitre <nico@marvell.com>
Tested-by: Peter van Valderen <linux@ddcrew.com>
Tested-by: Dirk Teurlings <dirk@upexia.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>