OCELOT_VCAP_IS2_TAG_8021Q_TXVLAN overlaps with OCELOT_VCAP_IS2_MRP_REDIRECT.
To avoid this, make OCELOT_VCAP_IS2_MRP_REDIRECT take the cookie region
from N to 2 * N - 1 (where N is ocelot->num_phys_ports).

To avoid any risk that the singleton (not per port) VCAP IS2 filters
overlap with per-port VCAP IS2 filters, we must ensure that the number
of singleton filters is smaller than the number of physical ports.
This is true right now, but may change in the future as switches with
less ports get supported, or more singleton filters get added. So to be
future-proof, let's move the singleton filters at the end of the range,
where they won't overlap with anything to their right.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The MRP assist code installs a VCAP IS2 trapping rule for each port, but
since the key and the action is the same, just the ingress port mask
differs, there isn't any need to do this. We can save some space in the
TCAM by using a single filter and adjusting the ingress port mask.

Reuse the ocelot_trap_add() and ocelot_trap_del() functions for this
purpose.

Now that the cookies are no longer per port, we need to change the
allocation scheme such that MRP traps use a fixed number.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

MRP frames are configured to be trapped to the CPU queue 7, and this
number is reflected in the extraction header. However, the information
isn't used anywhere, so just leave MRP frames to go to CPU queue 0
unless needed otherwise.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Every use case that needed VCAP filters (in order: DSA tag_8021q, MRP,
PTP traps) has hardcoded filter identifiers that worked well enough for
that use case alone. But when two or more of those use cases would be
used together, some of those identifiers would overlap, leading to
breakage.

Add definitions for each cookie and centralize them in ocelot_vcap.h,
such that the overlaps are more obvious.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The driver uses an identifier equal to (ocelot->num_phys_ports + port)
for MRP traps installed when the system is in the role of an MRC, and an
identifier equal to (port) otherwise.

Use the same identifier in both cases as a consolidation for the various
cookie values spread throughout the driver.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Saeed Mahameed says:

====================
mlx5-updates-2022-02-16

Misc updates for mlx5:
1) Alex Liu Adds support for using xdp->data_meta

2) Aya Levin Adds PTP counters and port time stamp mode for representors and
switchdev mode.

3) Tariq Toukan, Striding RQ simple improvements.

4) Roi Dayan (7): Create multiple attr instances per flow

Some TC actions use post actions for their implementation.
For example CT and sample actions.

Create a new flow attr instance after each multi table action and
create a post action rule for it as a generic parsing step.
Now multi table actions like CT, sample don't require to do it.

When flow has multiple attr instances, the first flow attr is being
offloaded normally and linked to the next attr (post action rule) by
setting an id on reg_c for matching.
Post action rule (rule created from second attr instance) match the
id on reg_c and does rest of the actions.

Example rule with actions CT,goto will be created with 2 attr instances
as following: attr1(CT)->attr2(goto)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Allow sample+CT actions but still block sample+CT NAT
as it is not supported.
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Before this commit post_act can be used for normal rules
and didn't handle special cases like CT and sample.
With this commit post_act rule can also handle the special cases
when needed.
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

When tc actions being parsed only the last flow attr created needs the
counter flag and the previous flags being reset.
Clean the flag from the tc action parsers.
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

CT and sample actions use post actions for their implementation.
Flag those actions as multi table actions so the post act infrastructure
will handle the post actions allocation.
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Some TC actions use post actions for their implementation.
For example CT and sample actions.

Create a new flow attr after each multi table action and
create a post action rule for it.

First flow attr being offloaded normally and linked to the next
attr (post action rule) with setting an id on reg_c.
Post action rules match the id on reg_c and continue to the next one.

The flow counter is allocated on the last rule.
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Introduce mlx5e_tc_post_act_offload() and mlx5e_tc_post_act_unoffload()
to be able to unoffload and reoffload existing post action rules handles.
For example in neigh update events, the driver removes and readds rules in
hardware.
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Currently the mlx5_flow object contains a single mlx5_attr instance.
However, multi table actions (e.g. CT) instantiate multiple attr instances.

Currently action_match_supported() reads the actions flag from the
flow's attribute instance. Modify the function to receive the action
flags as a parameter which is set by the calling function and
pass the aggregated actions to actions_match_supported().
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

To allow shared tc block offload between two or more reps of the
same eswitch, move the tc flow hashtable to be per rep, instead
of per eswitch.
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

When turning on tx_port_ts (private flag) a PTP-SQ is created. Consider
this queue when adding rules matching SQs to VPORTs. Otherwise the
traffic on this queue won't reach the wire.
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

There is a configuration where the uplink interface is the synchronizer.
Add PTP counters for this interface for monitoring.
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

In RQs of type multi-packet WQE (Striding RQ), each WQE is relatively
large (typically 256KB) but their number is relatively small (8 in
default).

Re-mapping the descriptors' buffers before re-posting them is done via
UMR (User-Mode Memory Registration) operations.

On the one hand, posting UMR WQEs in bulks reduces communication overhead
with the HW and better utilizes its processing units.
On the other hand, delaying the WQE repost operations for a small RQ
(say, of 4 WQEs) might drastically hit its performance, causing packet
drops due to no receive buffer, for high or bursty incoming packets rate.

Here we restrict the bulk size for too small RQs. Effectively, with the current
constants, RQ of size 4 (minimum allowed) would have no bulking, while larger
RQs will continue working with bulks of 2.
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

CQE compression is turned on by default on slow pci systems to help
reduce the load on pci.
In this case, Striding RQ was turned off as CQEs of packets that span
several strides were not compressed, significantly reducing the compression
effectiveness.
This issue does not exist when using the newer mini_cqe format "stride_index".
Hence, allow defaulting to Striding RQ in this case.
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Update the old error message for LRO state modify with the new
general name.
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Khalid Manaa <khalidm@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Add support for using xdp->data_meta for cross-program communication

Pass "true" to the last argument of xdp_prepare_buff().

After SKB is built, call skb_metadata_set() if metadata was pushed.
Signed-off-by: Alex Liu <liualex@fb.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

There is a spelling mistake in a NL_SET_ERR_MSG_MOD error
message.  Fix it.

Fixes: 3b49a7ed ("net/mlx5e: TC, Reject rules with multiple CT actions")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Both get and dump handlers for RTM_GETSTATS require that a filter_mask, a
mask of which attributes should be emitted in the netlink response, is
unset. rtnl_stats_dump() does include an extack in the bounce,
rtnl_stats_get() however does not. Fix the omission.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/01feb1f4bbd22a19f6629503c4f366aed6424567.1645020876.git.petrm@nvidia.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Mat Martineau says:

====================
mptcp: SO_SNDTIMEO and misc. cleanup

Patch 1 adds support for the SO_SNDTIMEO socket option on MPTCP sockets.

The remaining patches are various small cleanups:

Patch 2 removes an obsolete declaration.

Patches 3 and 5 remove unnecessary function parameters.

Patch 4 removes an extra cast.

Patches 6 and 7 add some const and ro_after_init modifiers.

Patch 8 removes extra storage of TCP helpers.
====================

Link: https://lore.kernel.org/r/20220216021130.171786-1-mathew.j.martineau@linux.intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Assign the helpers directly rather than save/restore in the context
structure.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

These structures are initialised from the init hooks, so we can't make
them 'const'.  But no writes occur afterwards, so we can use ro_after_init.

Also, remove bogus EXPORT_SYMBOL, the only access comes from ip
stack, not from kernel modules.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

A few pm-related helpers don't touch arguments which lacking
the const modifier, let's constify them.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Drop the port parameter of mptcp_pm_add_addr_signal() and reflect it to
avoid passing too many parameters.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Drop the unneeded type casts to 'unsigned long long' for printing out the
hmac values in add_addr_hmac_valid() and subflow_thmac_valid().
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The parameter 'sk' became useless since the code using it was dropped
from mptcp_get_options() in the commit 8d548ea1 ("mptcp: do not set
unconditionally csum_reqd on incoming opt"). Let's drop it.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Options parsing in now done from mptcp_incoming_options().

mptcp_parse_option() has been removed from mptcp.h when CONFIG_MPTCP is
defined but not when it is not.

Fixes: cfde141e ("mptcp: move option parsing into mptcp_incoming_options()")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Add setsockopt support for SO_SNDTIMEO_OLD and SO_SNDTIMEO_NEW to fix this
error reported by the mptcp bpf selftest:

 (network_helpers.c:64: errno: Operation not supported) Failed to set SO_SNDTIMEO
 test_mptcp:FAIL:115

 All error logs:

 (network_helpers.c:64: errno: Operation not supported) Failed to set SO_SNDTIMEO
 test_mptcp:FAIL:115
 Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The return from the call to dm9051_get_regs() is int, it can be
a negative error code, however this is being assigned to an unsigned
int variable 'ret', so making 'ret' an int.

Eliminate the following coccicheck warning:
./drivers/net/ethernet/davicom/dm9051.c:527:5-8: WARNING: Unsigned
expression compared with zero: ret < 0
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220216014507.109117-1-yang.lee@linux.alibaba.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

__skb_vlan_pop() needs skb->data to point at the mac_header, while
skb_vlan_tag_present() and skb_vlan_tag_get() don't, because they don't
look at skb->data at all.

So we can avoid uselessly moving around skb->data for the case where the
VLAN tag was offloaded by the DSA master.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220215204722.2134816-1-vladimir.oltean@nxp.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Replacements:
queueing to queuing
trasfer to transfer
aditional to additional
adaptor to adapter
transactino to transaction
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20220215213802.3043178-1-trix@redhat.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

When smc_connect_clc() times out, it will return -EAGAIN(tcp_recvmsg
retuns -EAGAIN while timeout), then this value will passed to the
application, which is quite confusing to the applications, makes
inconsistency with TCP.

From the manual of connect, ETIMEDOUT is more suitable, and this patch
try convert EAGAIN to ETIMEDOUT in that case.
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Karsten Graul <kgraul@linux.ibm.com>
Link: https://lore.kernel.org/r/1644913490-21594-1-git-send-email-alibuda@linux.alibaba.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

This is unused since commit 8e2288ca ("net: hns3: refactor PF
cmdq init and uninit APIs with new common APIs").
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Jie Wang <wangjie125@huawei.com>
Link: https://lore.kernel.org/r/20220216113507.22368-1-yuehaibing@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Vladimir Oltean says:

====================
Replay and offload host VLAN entries in DSA

v2->v3:
- make the bridge stop notifying switchdev for !BRENTRY VLANs
- create precommit and commit wrappers around __vlan_add_flags().
- special-case the BRENTRY transition from false to true, instead of
  treating it as a change of flags and letting drivers figure out that
  it really isn't.
- avoid setting *changed unless we know that functions will not error
  out later.
- drop "old_flags" from struct switchdev_obj_port_vlan, nobody needs it
  now, in v2 only DSA needed it to filter out BRENTRY transitions, that
  is now solved cleaner.
- no BRIDGE_VLAN_INFO_BRENTRY flag checks and manipulations in DSA
  whatsoever, use the "bool changed" bit as-is after changing what it
  means.
- merge dsa_slave_host_vlan_{add,del}() with
  dsa_slave_foreign_vlan_{add,del}(), since now they do the same thing,
  because the host_vlan functions no longer need to mangle the vlan
  BRENTRY flags and bool changed.

v1->v2:
- prune switchdev VLAN additions with no actual change differently
- no longer need to revert struct net_bridge_vlan changes on error from
  switchdev
- no longer need to first delete a changed VLAN before readding it
- pass 'bool changed' and 'u16 old_flags' through switchdev_obj_port_vlan
  so that DSA can do some additional post-processing with the
  BRIDGE_VLAN_INFO_BRENTRY flag
- support VLANs on foreign interfaces
- fix the same -EOPNOTSUPP error in mv88e6xxx, this time on removal, due
  to VLAN deletion getting replayed earlier than FDB deletion

The motivation behind these patches is that Rafael reported the
following error with mv88e6xxx when the first switch port joins a
bridge:

mv88e6085 0x0000000008b96000:00: port 0 failed to add a6:ef:77:c8:5f:3d vid 1 to fdb: -95 (-EOPNOTSUPP)

The FDB entry that's added is the MAC address of the bridge, in VID 1
(the default_pvid), being replayed as part of br_add_if() -> ... ->
nbp_switchdev_sync_objs().

-EOPNOTSUPP is the mv88e6xxx driver's way of saying that VID 1 doesn't
exist in the VTU, so it can't program the ATU with a FID, something
which it needs.

It appears to be a race, but it isn't, since we only end up installing
VID 1 in the VTU by coincidence. DSA's approximation of programming
VLANs on the CPU port together with the user ports breaks down with
host FDB entries on mv88e6xxx, since that strictly requires the VTU to
contain the VID. But the user may freely add VLANs pointing just towards
the bridge, and FDB entries in those VLANs, and DSA will not be aware of
them, because it only listens for VLANs on user ports.

To create a solution that scales properly to cross-chip setups and
doesn't leak entries behind, some changes in the bridge driver are
required. I believe that these are for the better overall, but I may be
wrong. Namely, the same refcounting procedure that DSA has in place for
host FDB and MDB entries can be replicated for VLANs, except that it's
garbage in, garbage out: the VLAN addition and removal notifications
from switchdev aren't balanced. So the first 2 patches attempt to deal
with that.

This patch set has been superficially tested on a board with 3 mv88e6xxx
switches in a daisy chain and appears to produce the primary desired
effect - the driver no longer returns -EOPNOTSUPP when the first port
joins a bridge, and is successful in performing local termination under
a VLAN-aware bridge.
As an additional side effect, it silences the annoying "p%d: already a
member of VLAN %d\n" warning messages that the mv88e6xxx driver produces
when coupled with systemd-networkd, and a few VLANs are configured.
Furthermore, it advances Florian's idea from a few years back, which
never got merged:
https://lore.kernel.org/lkml/20180624153339.13572-1-f.fainelli@gmail.com/
v2 has also been tested on the NXP LS1028A felix switch.

Some testing:

root@debian:~# bridge vlan add dev br0 vid 101 pvid self
[  100.709220] mv88e6085 d0032004.mdio-mii:10: mv88e6xxx_port_vlan_add: port 9 vlan 101
[  100.873426] mv88e6085 d0032004.mdio-mii:10: mv88e6xxx_port_vlan_add: port 10 vlan 101
[  100.892314] mv88e6085 d0032004.mdio-mii:11: mv88e6xxx_port_vlan_add: port 9 vlan 101
[  101.053392] mv88e6085 d0032004.mdio-mii:11: mv88e6xxx_port_vlan_add: port 10 vlan 101
[  101.076994] mv88e6085 d0032004.mdio-mii:12: mv88e6xxx_port_vlan_add: port 9 vlan 101
root@debian:~# bridge vlan add dev br0 vid 101 pvid self
root@debian:~# bridge vlan add dev br0 vid 101 pvid self
root@debian:~# bridge vlan
port              vlan-id
eth0              1 PVID Egress Untagged
lan9              1 PVID Egress Untagged
lan10             1 PVID Egress Untagged
lan11             1 PVID Egress Untagged
lan12             1 PVID Egress Untagged
lan13             1 PVID Egress Untagged
lan14             1 PVID Egress Untagged
lan15             1 PVID Egress Untagged
lan16             1 PVID Egress Untagged
lan17             1 PVID Egress Untagged
lan18             1 PVID Egress Untagged
lan19             1 PVID Egress Untagged
lan20             1 PVID Egress Untagged
lan21             1 PVID Egress Untagged
lan22             1 PVID Egress Untagged
lan23             1 PVID Egress Untagged
lan24             1 PVID Egress Untagged
sfp               1 PVID Egress Untagged
lan1              1 PVID Egress Untagged
lan2              1 PVID Egress Untagged
lan3              1 PVID Egress Untagged
lan4              1 PVID Egress Untagged
lan5              1 PVID Egress Untagged
lan6              1 PVID Egress Untagged
lan7              1 PVID Egress Untagged
lan8              1 PVID Egress Untagged
br0               1 Egress Untagged
                  101 PVID
root@debian:~# bridge vlan del dev br0 vid 101 pvid self
[  108.340487] mv88e6085 d0032004.mdio-mii:11: mv88e6xxx_port_vlan_del: port 9 vlan 101
[  108.379167] mv88e6085 d0032004.mdio-mii:11: mv88e6xxx_port_vlan_del: port 10 vlan 101
[  108.402319] mv88e6085 d0032004.mdio-mii:12: mv88e6xxx_port_vlan_del: port 9 vlan 101
[  108.425866] mv88e6085 d0032004.mdio-mii:10: mv88e6xxx_port_vlan_del: port 9 vlan 101
[  108.452280] mv88e6085 d0032004.mdio-mii:10: mv88e6xxx_port_vlan_del: port 10 vlan 101
root@debian:~# bridge vlan del dev br0 vid 101 pvid self
root@debian:~# bridge vlan del dev br0 vid 101 pvid self
root@debian:~# bridge vlan
port              vlan-id
eth0              1 PVID Egress Untagged
lan9              1 PVID Egress Untagged
lan10             1 PVID Egress Untagged
lan11             1 PVID Egress Untagged
lan12             1 PVID Egress Untagged
lan13             1 PVID Egress Untagged
lan14             1 PVID Egress Untagged
lan15             1 PVID Egress Untagged
lan16             1 PVID Egress Untagged
lan17             1 PVID Egress Untagged
lan18             1 PVID Egress Untagged
lan19             1 PVID Egress Untagged
lan20             1 PVID Egress Untagged
lan21             1 PVID Egress Untagged
lan22             1 PVID Egress Untagged
lan23             1 PVID Egress Untagged
lan24             1 PVID Egress Untagged
sfp               1 PVID Egress Untagged
lan1              1 PVID Egress Untagged
lan2              1 PVID Egress Untagged
lan3              1 PVID Egress Untagged
lan4              1 PVID Egress Untagged
lan5              1 PVID Egress Untagged
lan6              1 PVID Egress Untagged
lan7              1 PVID Egress Untagged
lan8              1 PVID Egress Untagged
br0               1 Egress Untagged
root@debian:~# bridge vlan del dev br0 vid 101 pvid self
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

DSA now explicitly handles VLANs installed with the 'self' flag on the
bridge as host VLANs, instead of just replicating every bridge port VLAN
also on the CPU port and never deleting it, which is what it did before.

However, this leaves a corner case uncovered, as explained by
Tobias Waldekranz:
https://patchwork.kernel.org/project/netdevbpf/patch/20220209213044.2353153-6-vladimir.oltean@nxp.com/#24735260

Forwarding towards a bridge port VLAN installed on a bridge port foreign
to DSA (separate NIC, Wi-Fi AP) used to work by virtue of the fact that
DSA itself needed to have at least one port in that VLAN (therefore, it
also had the CPU port in said VLAN). However, now that the CPU port may
not be member of all VLANs that user ports are members of, we need to
ensure this isn't the case if software forwarding to a foreign interface
is required.

The solution is to treat bridge port VLANs on standalone interfaces in
the exact same way as host VLANs. From DSA's perspective, there is no
difference between local termination and software forwarding; packets in
that VLAN must reach the CPU in both cases.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

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

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

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

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

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

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

Therefore:
- user ports contain only bridge port (forwarding) VLANs, and no
  refcounting is necessary
- DSA ports contain both forwarding and host VLANs. Refcounting is
  necessary among these 2 types.
- CPU ports contain only host VLANs. Refcounting is also necessary.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The switchdev_handle_port_obj_add() helper is good for replicating a
port object on the lower interfaces of @dev, if that object was emitted
on a bridge, or on a bridge port that is a LAG.

However, drivers that use this helper limit themselves to a box from
which they can no longer intercept port objects notified on neighbor
ports ("foreign interfaces").

One such driver is DSA, where software bridging with foreign interfaces
such as standalone NICs or Wi-Fi APs is an important use case. There, a
VLAN installed on a neighbor bridge port roughly corresponds to a
forwarding VLAN installed on the DSA switch's CPU port.

To support this use case while also making use of the benefits of the
switchdev_handle_* replication helper for port objects, introduce a new
variant of these functions that crawls through the neighbor ports of
@dev, in search of potentially compatible switchdev ports that are
interested in the event.

The strategy is identical to switchdev_handle_fdb_event_to_device():
if @dev wasn't a switchdev interface, then go one step upper, and
recursively call this function on the bridge that this port belongs to.
At the next recursion step, __switchdev_handle_port_obj_add() will
iterate through the bridge's lower interfaces. Among those, some will be
switchdev interfaces, and one will be the original @dev that we came
from. To prevent infinite recursion, we must suppress reentry into the
original @dev, and just call the @add_cb for the switchdev_interfaces.

It looks like this:

                br0
               / | \
              /  |  \
             /   |   \
           swp0 swp1 eth0

1. __switchdev_handle_port_obj_add(eth0)
   -> check_cb(eth0) returns false
   -> eth0 has no lower interfaces
   -> eth0's bridge is br0
   -> switchdev_lower_dev_find(br0, check_cb, foreign_dev_check_cb))
      finds br0

2. __switchdev_handle_port_obj_add(br0)
   -> check_cb(br0) returns false
   -> netdev_for_each_lower_dev
      -> check_cb(swp0) returns true, so we don't skip this interface

3. __switchdev_handle_port_obj_add(swp0)
   -> check_cb(swp0) returns true, so we call add_cb(swp0)

(back to netdev_for_each_lower_dev from 2)
      -> check_cb(swp1) returns true, so we don't skip this interface

4. __switchdev_handle_port_obj_add(swp1)
   -> check_cb(swp1) returns true, so we call add_cb(swp1)

(back to netdev_for_each_lower_dev from 2)
      -> check_cb(eth0) returns false, so we skip this interface to
         avoid infinite recursion

Note: eth0 could have been a LAG, and we don't want to suppress the
recursion through its lowers if those exist, so when check_cb() returns
false, we still call switchdev_lower_dev_find() to estimate whether
there's anything worth a recursion beneath that LAG. Using check_cb()
and foreign_dev_check_cb(), switchdev_lower_dev_find() not only figures
out whether the lowers of the LAG are switchdev, but also whether they
actively offload the LAG or not (whether the LAG is "foreign" to the
switchdev interface or not).

The port_obj_info->orig_dev is preserved across recursive calls, so
switchdev drivers still know on which device was this notification
originally emitted.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>