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  1. Oct 21, 2021
    • Vladimir Oltean's avatar
      net: mscc: ocelot: track the port pvid using a pointer · d4004422
      Vladimir Oltean authored 
      

Now that we have a list of struct ocelot_bridge_vlan entries, we can
rewrite the pvid logic to simply point to one of those structures,
instead of having a separate structure with a "bool valid".
The NULL pointer will represent the lack of a bridge pvid (not to be
confused with the lack of a hardware pvid on the port, that is present
at all times).

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d4004422
    • Vladimir Oltean's avatar
      net: mscc: ocelot: add the local station MAC addresses in VID 0 · bfbab310
      Vladimir Oltean authored 
      The ocelot switchdev driver does not include the CPU port in the list of
flooding destinations for unknown traffic, instead that traffic is
supposed to match FDB entries to reach the CPU.

The addresses it installs are:
(a) the station MAC address, in ocelot_probe_port() and later during
    runtime in ocelot_port_set_mac_address(). These are the VLAN-unaware
    addresses. The VLAN-aware addresses are in ocelot_vlan_vid_add().
(b) multicast addresses added with dev_mc_add() (not bridge host MDB
    entries) in ocelot_mc_sync()
(c) multicast destination MAC addresses for MRP in ocelot_mrp_save_mac(),
    to make sure those are dropped (not forwarded) by the bridging
    service, just trapped to the CPU

So we can see that the logic is slightly buggy ever since the initial
commit a556c76a

 ("net: mscc: Add initial Ocelot switch support").
This is because, when ocelot_probe_port() runs, the port pvid is 0.
Then we join a VLAN-aware bridge, the pvid becomes 1, we call
ocelot_port_set_mac_address(), this learns the new MAC address in VID 1
(also fails to forget the old one, since it thinks it's in VID 1, but
that's not so important). Then when we leave the VLAN-aware bridge,
outside world is unable to ping our new MAC address because it isn't
learned in VID 0, the VLAN-unaware pvid.

[ note: this is strictly based on static analysis, I don't have hardware
  to test. But there are also many more corner cases ]

The basic idea is that we should have a separation of concerns, and the
FDB entries used for standalone operation should be managed by the
driver, and the FDB entries used by the bridging service should be
managed by the bridge. So the standalone and VLAN-unaware bridge FDB
entries should not follow the bridge PVID, because that will only be
active when the bridge is VLAN-aware. So since the port pvid is
coincidentally zero during probe time, just make those entries
statically go to VID 0.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bfbab310
    • Vladimir Oltean's avatar
      net: mscc: ocelot: allow a config where all bridge VLANs are egress-untagged · 0da1a1c4
      Vladimir Oltean authored 
      

At present, the ocelot driver accepts a single egress-untagged bridge
VLAN, meaning that this sequence of operations:

ip link add br0 type bridge vlan_filtering 1
ip link set swp0 master br0
bridge vlan add dev swp0 vid 2 pvid untagged

fails because the bridge automatically installs VID 1 as a pvid & untagged
VLAN, and vid 2 would be the second untagged VLAN on this port. It is
necessary to delete VID 1 before proceeding to add VID 2.

This limitation comes from the fact that we operate the port tag, when
it has an egress-untagged VID, in the OCELOT_PORT_TAG_NATIVE mode.
The ocelot switches do not have full flexibility and can either have one
single VID as egress-untagged, or all of them.

There are use cases for having all VLANs as egress-untagged as well, and
this patch adds support for that.

The change rewrites ocelot_port_set_native_vlan() into a more generic
ocelot_port_manage_port_tag() function. Because the software bridge's
state, transmitted to us via switchdev, can become very complex, we
don't attempt to track all possible state transitions, but instead take
a more declarative approach and just make ocelot_port_manage_port_tag()
figure out which more to operate in:

- port is VLAN-unaware: the classified VLAN (internal, unrelated to the
                        802.1Q header) is not inserted into packets on egress
- port is VLAN-aware:
  - port has tagged VLANs:
    -> port has no untagged VLAN: set up as pure trunk
    -> port has one untagged VLAN: set up as trunk port + native VLAN
    -> port has more than one untagged VLAN: this is an invalid config
       which is rejected by ocelot_vlan_prepare
  - port has no tagged VLANs
    -> set up as pure egress-untagged port

We don't keep the number of tagged and untagged VLANs, we just count the
structures we keep.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0da1a1c4
    • Vladimir Oltean's avatar
      net: mscc: ocelot: convert the VLAN masks to a list · 90e0aa8d
      Vladimir Oltean authored 
      

First and foremost, the driver currently allocates a constant sized
4K * u32 (16KB memory) array for the VLAN masks. However, a typical
application might not need so many VLANs, so if we dynamically allocate
the memory as needed, we might actually save some space.

Secondly, we'll need to keep more advanced bookkeeping of the VLANs we
have, notably we'll have to check how many untagged and how many tagged
VLANs we have. This will have to stay in a structure, and allocating
another 16 KB array for that is again a bit too much.

So refactor the bridge VLANs in a linked list of structures.

The hook points inside the driver are ocelot_vlan_member_add() and
ocelot_vlan_member_del(), which previously used to operate on the
ocelot->vlan_mask[vid] array element.

ocelot_vlan_member_add() and ocelot_vlan_member_del() used to call
ocelot_vlan_member_set() to commit to the ocelot->vlan_mask.
Additionally, we had two calls to ocelot_vlan_member_set() from outside
those callers, and those were directly from ocelot_vlan_init().
Those calls do not set up bridging service VLANs, instead they:

- clear the VLAN table on reset
- set the port pvid to the value used by this driver for VLAN-unaware
  standalone port operation (VID 0)

So now, when we have a structure which represents actual bridge VLANs,
VID 0 doesn't belong in that structure, since it is not part of the
bridging layer.

So delete the middle man, ocelot_vlan_member_set(), and let
ocelot_vlan_init() call directly ocelot_vlant_set_mask() which forgoes
any data structure and writes directly to hardware, which is all that we
need.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      90e0aa8d
    • Vladimir Oltean's avatar
      net: mscc: ocelot: add a type definition for REW_TAG_CFG_TAG_CFG · 62a22bcb
      Vladimir Oltean authored 
      

This is a cosmetic patch which clarifies what are the port tagging
options for Ocelot switches.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      62a22bcb
    • Toke Høiland-Jørgensen's avatar
      fq_codel: generalise ce_threshold marking for subset of traffic · dfcb63ce
      Toke Høiland-Jørgensen authored 
      Commit e72aeb9e

 ("fq_codel: implement L4S style ce_threshold_ect1
marking") expanded the ce_threshold feature of FQ-CoDel so it can
be applied to a subset of the traffic, using the ECT(1) bit of the ECN
field as the classifier. However, hard-coding ECT(1) as the only
classifier for this feature seems limiting, so let's expand it to be more
general.

To this end, change the parameter from a ce_threshold_ect1 boolean, to a
one-byte selector/mask pair (ce_threshold_{selector,mask}) which is applied
to the whole diffserv/ECN field in the IP header. This makes it possible to
classify packets by any value in either the ECN field or the diffserv
field. In particular, setting a selector of INET_ECN_ECT_1 and a mask of
INET_ECN_MASK corresponds to the functionality before this patch, and a
mask of ~INET_ECN_MASK allows using the selector as a straight-forward
match against a diffserv code point:

 # apply ce_threshold to ECT(1) traffic
 tc qdisc replace dev eth0 root fq_codel ce_threshold 1ms ce_threshold_selector 0x1/0x3

 # apply ce_threshold to ECN-capable traffic marked as diffserv AF22
 tc qdisc replace dev eth0 root fq_codel ce_threshold 1ms ce_threshold_selector 0x50/0xfc

Regardless of the selector chosen, the normal rules for ECN-marking of
packets still apply, i.e., the flow must still declare itself ECN-capable
by setting one of the bits in the ECN field to get marked at all.

v2:
- Add tc usage examples to patch description

Signed-off-by: default avatarToke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20211019174709.69081-1-toke@redhat.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      dfcb63ce
  3. Oct 20, 2021