Commit Graph

1201 Commits

Author SHA1 Message Date
Hans Schultz
b9e8b58fd2 net: dsa: Include BR_PORT_LOCKED in the list of synced brport flags
Ensures that the DSA switch driver gets notified of changes to the
BR_PORT_LOCKED flag as well, for the case when a DSA port joins or
leaves a LAG that is a bridge port.

Signed-off-by: Hans Schultz <schultz.hans+netdev@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-23 12:52:34 +00:00
Russell King (Oracle)
1054457006 net: phy: phylink: fix DSA mac_select_pcs() introduction
Vladimir Oltean reports that probing on DSA drivers that aren't yet
populating supported_interfaces now fails. Fix this by allowing
phylink to detect whether DSA actually provides an underlying
mac_select_pcs() implementation.

Reported-by: Vladimir Oltean <olteanv@gmail.com>
Fixes: bde018222c ("net: dsa: add support for phylink mac_select_pcs()")
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/E1nMCD6-00A0wC-FG@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-22 16:57:08 -08:00
Russell King (Oracle)
ccfbf44d4c net: dsa: remove pcs_poll
With drivers converted over to using phylink PCS, there is no need for
the struct dsa_switch member "pcs_poll" to exist anymore - there is a
flag in the struct phylink_pcs which indicates whether this PCS needs
to be polled which supersedes this.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-19 16:41:50 +00:00
Russell King (Oracle)
bde018222c net: dsa: add support for phylink mac_select_pcs()
Add DSA support for the phylink mac_select_pcs() method so DSA drivers
can return provide phylink with the appropriate PCS for the PHY
interface mode.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-18 11:28:32 +00:00
Vladimir Oltean
d2b1d186ce net: dsa: delete unused exported symbols for ethtool PHY stats
Introduced in commit cf96357303 ("net: dsa: Allow providing PHY
statistics from CPU port"), it appears these were never used.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220216193726.2926320-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 20:07:09 -08:00
Jakub Kicinski
6b5567b1b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 11:44:20 -08:00
Mans Rullgard
017b355bbd net: dsa: lan9303: handle hwaccel VLAN tags
Check for a hwaccel VLAN tag on rx and use it if present.  Otherwise,
use __skb_vlan_pop() like the other tag parsers do.  This fixes the case
where the VLAN tag has already been consumed by the master.

Fixes: a1292595e0 ("net: dsa: add new DSA switch driver for the SMSC-LAN9303")
Signed-off-by: Mans Rullgard <mans@mansr.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20220216124634.23123-1-mans@mansr.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 09:32:06 -08:00
Vladimir Oltean
29940ce32a net: dsa: tag_ocelot_8021q: calculate TX checksum in software for deferred packets
DSA inherits NETIF_F_CSUM_MASK from master->vlan_features, and the
expectation is that TX checksumming is offloaded and not done in
software.

Normally the DSA master takes care of this, but packets handled by
ocelot_defer_xmit() are a very special exception, because they are
actually injected into the switch through register-based MMIO. So the
DSA master is not involved at all for these packets => no one calculates
the checksum.

This allows PTP over UDP to work using the ocelot-8021q tagging
protocol.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-17 14:06:51 +00:00
Vladimir Oltean
c862033595 net: dsa: tag_8021q: only call skb_push/skb_pull around __skb_vlan_pop
__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.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:35:35 -08:00
Vladimir Oltean
164f861bd4 net: dsa: offload bridge port VLANs on foreign interfaces
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>
2022-02-16 11:21:05 +00:00
Vladimir Oltean
134ef2388e net: dsa: add explicit support for host bridge VLANs
Currently, DSA programs VLANs on shared (DSA and CPU) ports each time it
does so on user ports. This is good for basic functionality but has
several limitations:

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

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

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

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

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

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

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

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-16 11:21:05 +00:00
Vladimir Oltean
a2614140dc net: dsa: mv88e6xxx: flush switchdev FDB workqueue before removing VLAN
mv88e6xxx is special among DSA drivers in that it requires the VTU to
contain the VID of the FDB entry it modifies in
mv88e6xxx_port_db_load_purge(), otherwise it will return -EOPNOTSUPP.

Sometimes due to races this is not always satisfied even if external
code does everything right (first deletes the FDB entries, then the
VLAN), because DSA commits to hardware FDB entries asynchronously since
commit c9eb3e0f87 ("net: dsa: Add support for learning FDB through
notification").

Therefore, the mv88e6xxx driver must close this race condition by
itself, by asking DSA to flush the switchdev workqueue of any FDB
deletions in progress, prior to exiting a VLAN.

Fixes: c9eb3e0f87 ("net: dsa: Add support for learning FDB through notification")
Reported-by: Rafael Richter <rafael.richter@gin.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-14 13:31:12 +00:00
Vladimir Oltean
ddb44bdcde net: dsa: remove lockdep class for DSA slave address list
Since commit 2f1e8ea726 ("net: dsa: link interfaces with the DSA
master to get rid of lockdep warnings"), suggested by Cong Wang, the
DSA interfaces and their master have different dev->nested_level, which
makes netif_addr_lock() stop complaining about potentially recursive
locking on the same lock class.

So we no longer need DSA slave interfaces to have their own lockdep
class.

Cc: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-11 11:17:33 +00:00
Vladimir Oltean
8db2bc790d net: dsa: remove lockdep class for DSA master address list
Since commit 2f1e8ea726 ("net: dsa: link interfaces with the DSA
master to get rid of lockdep warnings"), suggested by Cong Wang, the
DSA interfaces and their master have different dev->nested_level, which
makes netif_addr_lock() stop complaining about potentially recursive
locking on the same lock class.

So we no longer need DSA masters to have their own lockdep class.

Cc: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-11 11:17:32 +00:00
Vladimir Oltean
45b987d5ed net: dsa: remove ndo_get_phys_port_name and ndo_get_port_parent_id
There are no legacy ports, DSA registers a devlink instance with ports
unconditionally for all switch drivers. Therefore, delete the old-style
ndo operations used for determining bridge forwarding domains.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-11 11:17:32 +00:00
Jakub Kicinski
5b91c5cc0e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-10 17:29:56 -08:00
Vladimir Oltean
ee534378f0 net: dsa: fix panic when DSA master device unbinds on shutdown
Rafael reports that on a system with LX2160A and Marvell DSA switches,
if a reboot occurs while the DSA master (dpaa2-eth) is up, the following
panic can be seen:

systemd-shutdown[1]: Rebooting.
Unable to handle kernel paging request at virtual address 00a0000800000041
[00a0000800000041] address between user and kernel address ranges
Internal error: Oops: 96000004 [#1] PREEMPT SMP
CPU: 6 PID: 1 Comm: systemd-shutdow Not tainted 5.16.5-00042-g8f5585009b24 #32
pc : dsa_slave_netdevice_event+0x130/0x3e4
lr : raw_notifier_call_chain+0x50/0x6c
Call trace:
 dsa_slave_netdevice_event+0x130/0x3e4
 raw_notifier_call_chain+0x50/0x6c
 call_netdevice_notifiers_info+0x54/0xa0
 __dev_close_many+0x50/0x130
 dev_close_many+0x84/0x120
 unregister_netdevice_many+0x130/0x710
 unregister_netdevice_queue+0x8c/0xd0
 unregister_netdev+0x20/0x30
 dpaa2_eth_remove+0x68/0x190
 fsl_mc_driver_remove+0x20/0x5c
 __device_release_driver+0x21c/0x220
 device_release_driver_internal+0xac/0xb0
 device_links_unbind_consumers+0xd4/0x100
 __device_release_driver+0x94/0x220
 device_release_driver+0x28/0x40
 bus_remove_device+0x118/0x124
 device_del+0x174/0x420
 fsl_mc_device_remove+0x24/0x40
 __fsl_mc_device_remove+0xc/0x20
 device_for_each_child+0x58/0xa0
 dprc_remove+0x90/0xb0
 fsl_mc_driver_remove+0x20/0x5c
 __device_release_driver+0x21c/0x220
 device_release_driver+0x28/0x40
 bus_remove_device+0x118/0x124
 device_del+0x174/0x420
 fsl_mc_bus_remove+0x80/0x100
 fsl_mc_bus_shutdown+0xc/0x1c
 platform_shutdown+0x20/0x30
 device_shutdown+0x154/0x330
 __do_sys_reboot+0x1cc/0x250
 __arm64_sys_reboot+0x20/0x30
 invoke_syscall.constprop.0+0x4c/0xe0
 do_el0_svc+0x4c/0x150
 el0_svc+0x24/0xb0
 el0t_64_sync_handler+0xa8/0xb0
 el0t_64_sync+0x178/0x17c

It can be seen from the stack trace that the problem is that the
deregistration of the master causes a dev_close(), which gets notified
as NETDEV_GOING_DOWN to dsa_slave_netdevice_event().
But dsa_switch_shutdown() has already run, and this has unregistered the
DSA slave interfaces, and yet, the NETDEV_GOING_DOWN handler attempts to
call dev_close_many() on those slave interfaces, leading to the problem.

The previous attempt to avoid the NETDEV_GOING_DOWN on the master after
dsa_switch_shutdown() was called seems improper. Unregistering the slave
interfaces is unnecessary and unhelpful. Instead, after the slaves have
stopped being uppers of the DSA master, we can now reset to NULL the
master->dsa_ptr pointer, which will make DSA start ignoring all future
notifier events on the master.

Fixes: 0650bf52b3 ("net: dsa: be compatible with masters which unregister on shutdown")
Reported-by: Rafael Richter <rafael.richter@gin.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-09 13:21:39 +00:00
Ansuel Smith
31eb6b4386 net: dsa: tag_qca: add support for handling mgmt and MIB Ethernet packet
Add connect/disconnect helper to assign private struct to the DSA switch.
Add support for Ethernet mgmt and MIB if the DSA driver provide an handler
to correctly parse and elaborate the data.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Ansuel Smith
18be654a43 net: dsa: tag_qca: add define for handling MIB packet
Add struct to correctly parse a mib Ethernet packet.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Ansuel Smith
c2ee8181fd net: dsa: tag_qca: add define for handling mgmt Ethernet packet
Add all the required define to prepare support for mgmt read/write in
Ethernet packet. Any packet of this type has to be dropped as the only
use of these special packet is receive ack for an mgmt write request or
receive data for an mgmt read request.
A struct is used that emulates the Ethernet header but is used for a
different purpose.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Ansuel Smith
101c04c346 net: dsa: tag_qca: enable promisc_on_master flag
Ethernet MDIO packets are non-standard and DSA master expects the first
6 octets to be the MAC DA. To address these kind of packet, enable
promisc_on_master flag for the tagger.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Ansuel Smith
3ec762fb13 net: dsa: tag_qca: move define to include linux/dsa
Move tag_qca define to include dir linux/dsa as the qca8k require access
to the tagger define to support in-band mdio read/write using ethernet
packet.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Ansuel Smith
6b04582992 net: dsa: tag_qca: convert to FIELD macro
Convert driver to FIELD macro to drop redundant define.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Vladimir Oltean
e83d565378 net: dsa: replay master state events in dsa_tree_{setup,teardown}_master
In order for switch driver to be able to make simple and reliable use of
the master tracking operations, they must also be notified of the
initial state of the DSA master, not just of the changes. This is
because they might enable certain features only during the time when
they know that the DSA master is up and running.

Therefore, this change explicitly checks the state of the DSA master
under the same rtnl_mutex as we were holding during the
dsa_master_setup() and dsa_master_teardown() call. The idea being that
if the DSA master became operational in between the moment in which it
became a DSA master (dsa_master_setup set dev->dsa_ptr) and the moment
when we checked for the master being up, there is a chance that we
would emit a ->master_state_change() call with no actual state change.
We need to avoid that by serializing the concurrent netdevice event with
us. If the netdevice event started before, we force it to finish before
we begin, because we take rtnl_lock before making netdev_uses_dsa()
return true. So we also handle that early event and do nothing on it.
Similarly, if the dev_open() attempt is concurrent with us, it will
attempt to take the rtnl_mutex, but we're holding it. We'll see that
the master flag IFF_UP isn't set, then when we release the rtnl_mutex
we'll process the NETDEV_UP notifier.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Vladimir Oltean
295ab96f47 net: dsa: provide switch operations for tracking the master state
Certain drivers may need to send management traffic to the switch for
things like register access, FDB dump, etc, to accelerate what their
slow bus (SPI, I2C, MDIO) can already do.

Ethernet is faster (especially in bulk transactions) but is also more
unreliable, since the user may decide to bring the DSA master down (or
not bring it up), therefore severing the link between the host and the
attached switch.

Drivers needing Ethernet-based register access already should have
fallback logic to the slow bus if the Ethernet method fails, but that
fallback may be based on a timeout, and the I/O to the switch may slow
down to a halt if the master is down, because every Ethernet packet will
have to time out. The driver also doesn't have the option to turn off
Ethernet-based I/O momentarily, because it wouldn't know when to turn it
back on.

Which is where this change comes in. By tracking NETDEV_CHANGE,
NETDEV_UP and NETDEV_GOING_DOWN events on the DSA master, we should know
the exact interval of time during which this interface is reliably
available for traffic. Provide this information to switches so they can
use it as they wish.

An helper is added dsa_port_master_is_operational() to check if a master
port is operational.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02 14:43:59 +00:00
Tobias Waldekranz
108dc8741c net: dsa: Avoid cross-chip syncing of VLAN filtering
Changes to VLAN filtering are not applicable to cross-chip
notifications.

On a system like this:

.-----.   .-----.   .-----.
| sw1 +---+ sw2 +---+ sw3 |
'-1-2-'   '-1-2-'   '-1-2-'

Before this change, upon sw1p1 leaving a bridge, a call to
dsa_port_vlan_filtering would also be made to sw2p1 and sw3p1.

In this scenario:

.---------.   .-----.   .-----.
|   sw1   +---+ sw2 +---+ sw3 |
'-1-2-3-4-'   '-1-2-'   '-1-2-'

When sw1p4 would leave a bridge, dsa_port_vlan_filtering would be
called for sw2 and sw3 with a non-existing port - leading to array
out-of-bounds accesses and crashes on mv88e6xxx.

Fixes: d371b7c92d ("net: dsa: Unset vlan_filtering when ports leave the bridge")
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-25 11:45:39 +00:00
Tobias Waldekranz
381a730182 net: dsa: Move VLAN filtering syncing out of dsa_switch_bridge_leave
Most of dsa_switch_bridge_leave was, in fact, dealing with the syncing
of VLAN filtering for switches on which that is a global
setting. Separate the two phases to prepare for the cross-chip related
bugfix in the following commit.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-25 11:45:39 +00:00
Vladimir Oltean
11fd667dac net: dsa: setup master before ports
It is said that as soon as a network interface is registered, all its
resources should have already been prepared, so that it is available for
sending and receiving traffic. One of the resources needed by a DSA
slave interface is the master.

dsa_tree_setup
-> dsa_tree_setup_ports
   -> dsa_port_setup
      -> dsa_slave_create
         -> register_netdevice
-> dsa_tree_setup_master
   -> dsa_master_setup
      -> sets up master->dsa_ptr, which enables reception

Therefore, there is a short period of time after register_netdevice()
during which the master isn't prepared to pass traffic to the DSA layer
(master->dsa_ptr is checked by eth_type_trans). Same thing during
unregistration, there is a time frame in which packets might be missed.

Note that this change opens us to another race: dsa_master_find_slave()
will get invoked potentially earlier than the slave creation, and later
than the slave deletion. Since dp->slave starts off as a NULL pointer,
the earlier calls aren't a problem, but the later calls are. To avoid
use-after-free, we should zeroize dp->slave before calling
dsa_slave_destroy().

In practice I cannot really test real life improvements brought by this
change, since in my systems, netdevice creation races with PHY autoneg
which takes a few seconds to complete, and that masks quite a few races.
Effects might be noticeable in a setup with fixed links all the way to
an external system.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06 11:59:10 +00:00
Vladimir Oltean
1e3f407f3c net: dsa: first set up shared ports, then non-shared ports
After commit a57d8c217a ("net: dsa: flush switchdev workqueue before
tearing down CPU/DSA ports"), the port setup and teardown procedure
became asymmetric.

The fact of the matter is that user ports need the shared ports to be up
before they can be used for CPU-initiated termination. And since we
register net devices for the user ports, those won't be functional until
we also call the setup for the shared (CPU, DSA) ports. But we may do
that later, depending on the port numbering scheme of the hardware we
are dealing with.

It just makes sense that all shared ports are brought up before any user
port is. I can't pinpoint any issue due to the current behavior, but
let's change it nonetheless, for consistency's sake.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06 11:59:10 +00:00
Vladimir Oltean
c146f9bc19 net: dsa: hold rtnl_mutex when calling dsa_master_{setup,teardown}
DSA needs to simulate master tracking events when a binding is first
with a DSA master established and torn down, in order to give drivers
the simplifying guarantee that ->master_state_change calls are made
only when the master's readiness state to pass traffic changes.
master_state_change() provide a operational bool that DSA driver can use
to understand if DSA master is operational or not.
To avoid races, we need to block the reception of
NETDEV_UP/NETDEV_CHANGE/NETDEV_GOING_DOWN events in the netdev notifier
chain while we are changing the master's dev->dsa_ptr (this changes what
netdev_uses_dsa(dev) reports).

The dsa_master_setup() and dsa_master_teardown() functions optionally
require the rtnl_mutex to be held, if the tagger needs the master to be
promiscuous, these functions call dev_set_promiscuity(). Move the
rtnl_lock() from that function and make it top-level.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06 11:59:10 +00:00
Vladimir Oltean
a1ff94c297 net: dsa: stop updating master MTU from master.c
At present there are two paths for changing the MTU of the DSA master.

The first is:

dsa_tree_setup
-> dsa_tree_setup_ports
   -> dsa_port_setup
      -> dsa_slave_create
         -> dsa_slave_change_mtu
            -> dev_set_mtu(master)

The second is:

dsa_tree_setup
-> dsa_tree_setup_master
   -> dsa_master_setup
      -> dev_set_mtu(dev)

So the dev_set_mtu() call from dsa_master_setup() has been effectively
superseded by the dsa_slave_change_mtu(slave_dev, ETH_DATA_LEN) that is
done from dsa_slave_create() for each user port. The later function also
updates the master MTU according to the largest user port MTU from the
tree. Therefore, updating the master MTU through a separate code path
isn't needed.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06 11:59:09 +00:00
Vladimir Oltean
e31dbd3b6a net: dsa: merge rtnl_lock sections in dsa_slave_create
Currently dsa_slave_create() has two sequences of rtnl_lock/rtnl_unlock
in a row. Remove the rtnl_unlock() and rtnl_lock() in between, such that
the operation can execute slighly faster.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06 11:59:09 +00:00
Vladimir Oltean
904e112ad4 net: dsa: reorder PHY initialization with MTU setup in slave.c
In dsa_slave_create() there are 2 sections that take rtnl_lock():
MTU change and netdev registration. They are separated by PHY
initialization.

There isn't any strict ordering requirement except for the fact that
netdev registration should be last. Therefore, we can perform the MTU
change a bit later, after the PHY setup. A future change will then be
able to merge the two rtnl_lock sections into one.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06 11:59:09 +00:00
Vladimir Oltean
a68dc7b938 net: dsa: remove cross-chip support for HSR
The cross-chip notifiers for HSR are bypass operations, meaning that
even though all switches in a tree are notified, only the switch
specified in the info structure is targeted.

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

Cc: George McCollister <george.mccollister@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: George McCollister <george.mccollister@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05 15:04:51 +00:00
Vladimir Oltean
cad69019f2 net: dsa: remove cross-chip support for MRP
The cross-chip notifiers for MRP are bypass operations, meaning that
even though all switches in a tree are notified, only the switch
specified in the info structure is targeted.

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

Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05 15:04:50 +00:00
Vladimir Oltean
ff91e1b684 net: dsa: fix incorrect function pointer check for MRP ring roles
The cross-chip notifier boilerplate code meant to check the presence of
ds->ops->port_mrp_add_ring_role before calling it, but checked
ds->ops->port_mrp_add instead, before calling
ds->ops->port_mrp_add_ring_role.

Therefore, a driver which implements one operation but not the other
would trigger a NULL pointer dereference.

There isn't any such driver in DSA yet, so there is no reason to
backport the change. Issue found through code inspection.

Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Fixes: c595c4330d ("net: dsa: add MRP support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05 15:04:50 +00:00
Vladimir Oltean
258030acc9 net: dsa: make dsa_switch :: num_ports an unsigned int
Currently, num_ports is declared as size_t, which is defined as
__kernel_ulong_t, therefore it occupies 8 bytes of memory.

Even switches with port numbers in the range of tens are exotic, so
there is no need for this amount of storage.

Additionally, because the max_num_bridges member right above it is also
4 bytes, it means the compiler needs to add padding between the last 2
fields. By reducing the size, we don't need that padding and can reduce
the struct size.

Before:

pahole -C dsa_switch net/dsa/slave.o
struct dsa_switch {
        struct device *            dev;                  /*     0     8 */
        struct dsa_switch_tree *   dst;                  /*     8     8 */
        unsigned int               index;                /*    16     4 */
        u32                        setup:1;              /*    20: 0  4 */
        u32                        vlan_filtering_is_global:1; /*    20: 1  4 */
        u32                        needs_standalone_vlan_filtering:1; /*    20: 2  4 */
        u32                        configure_vlan_while_not_filtering:1; /*    20: 3  4 */
        u32                        untag_bridge_pvid:1;  /*    20: 4  4 */
        u32                        assisted_learning_on_cpu_port:1; /*    20: 5  4 */
        u32                        vlan_filtering:1;     /*    20: 6  4 */
        u32                        pcs_poll:1;           /*    20: 7  4 */
        u32                        mtu_enforcement_ingress:1; /*    20: 8  4 */

        /* XXX 23 bits hole, try to pack */

        struct notifier_block      nb;                   /*    24    24 */

        /* XXX last struct has 4 bytes of padding */

        void *                     priv;                 /*    48     8 */
        void *                     tagger_data;          /*    56     8 */
        /* --- cacheline 1 boundary (64 bytes) --- */
        struct dsa_chip_data *     cd;                   /*    64     8 */
        const struct dsa_switch_ops  * ops;              /*    72     8 */
        u32                        phys_mii_mask;        /*    80     4 */

        /* XXX 4 bytes hole, try to pack */

        struct mii_bus *           slave_mii_bus;        /*    88     8 */
        unsigned int               ageing_time_min;      /*    96     4 */
        unsigned int               ageing_time_max;      /*   100     4 */
        struct dsa_8021q_context * tag_8021q_ctx;        /*   104     8 */
        struct devlink *           devlink;              /*   112     8 */
        unsigned int               num_tx_queues;        /*   120     4 */
        unsigned int               num_lag_ids;          /*   124     4 */
        /* --- cacheline 2 boundary (128 bytes) --- */
        unsigned int               max_num_bridges;      /*   128     4 */

        /* XXX 4 bytes hole, try to pack */

        size_t                     num_ports;            /*   136     8 */

        /* size: 144, cachelines: 3, members: 27 */
        /* sum members: 132, holes: 2, sum holes: 8 */
        /* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 23 bits */
        /* paddings: 1, sum paddings: 4 */
        /* last cacheline: 16 bytes */
};

After:

pahole -C dsa_switch net/dsa/slave.o
struct dsa_switch {
        struct device *            dev;                  /*     0     8 */
        struct dsa_switch_tree *   dst;                  /*     8     8 */
        unsigned int               index;                /*    16     4 */
        u32                        setup:1;              /*    20: 0  4 */
        u32                        vlan_filtering_is_global:1; /*    20: 1  4 */
        u32                        needs_standalone_vlan_filtering:1; /*    20: 2  4 */
        u32                        configure_vlan_while_not_filtering:1; /*    20: 3  4 */
        u32                        untag_bridge_pvid:1;  /*    20: 4  4 */
        u32                        assisted_learning_on_cpu_port:1; /*    20: 5  4 */
        u32                        vlan_filtering:1;     /*    20: 6  4 */
        u32                        pcs_poll:1;           /*    20: 7  4 */
        u32                        mtu_enforcement_ingress:1; /*    20: 8  4 */

        /* XXX 23 bits hole, try to pack */

        struct notifier_block      nb;                   /*    24    24 */

        /* XXX last struct has 4 bytes of padding */

        void *                     priv;                 /*    48     8 */
        void *                     tagger_data;          /*    56     8 */
        /* --- cacheline 1 boundary (64 bytes) --- */
        struct dsa_chip_data *     cd;                   /*    64     8 */
        const struct dsa_switch_ops  * ops;              /*    72     8 */
        u32                        phys_mii_mask;        /*    80     4 */

        /* XXX 4 bytes hole, try to pack */

        struct mii_bus *           slave_mii_bus;        /*    88     8 */
        unsigned int               ageing_time_min;      /*    96     4 */
        unsigned int               ageing_time_max;      /*   100     4 */
        struct dsa_8021q_context * tag_8021q_ctx;        /*   104     8 */
        struct devlink *           devlink;              /*   112     8 */
        unsigned int               num_tx_queues;        /*   120     4 */
        unsigned int               num_lag_ids;          /*   124     4 */
        /* --- cacheline 2 boundary (128 bytes) --- */
        unsigned int               max_num_bridges;      /*   128     4 */
        unsigned int               num_ports;            /*   132     4 */

        /* size: 136, cachelines: 3, members: 27 */
        /* sum members: 128, holes: 1, sum holes: 4 */
        /* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 23 bits */
        /* paddings: 1, sum paddings: 4 */
        /* last cacheline: 8 bytes */
};

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05 14:46:23 +00:00
David S. Miller
e63a023489 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-12-30

The following pull-request contains BPF updates for your *net-next* tree.

We've added 72 non-merge commits during the last 20 day(s) which contain
a total of 223 files changed, 3510 insertions(+), 1591 deletions(-).

The main changes are:

1) Automatic setrlimit in libbpf when bpf is memcg's in the kernel, from Andrii.

2) Beautify and de-verbose verifier logs, from Christy.

3) Composable verifier types, from Hao.

4) bpf_strncmp helper, from Hou.

5) bpf.h header dependency cleanup, from Jakub.

6) get_func_[arg|ret|arg_cnt] helpers, from Jiri.

7) Sleepable local storage, from KP.

8) Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support, from Kumar.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-31 14:35:40 +00:00
Jakub Kicinski
b6459415b3 net: Don't include filter.h from net/sock.h
sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
2021-12-29 08:48:14 -08:00
Jakub Kicinski
8b3f913322 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/net/sock.h
  commit 8f905c0e73 ("inet: fully convert sk->sk_rx_dst to RCU rules")
  commit 43f51df417 ("net: move early demux fields close to sk_refcnt")
  https://lore.kernel.org/all/20211222141641.0caa0ab3@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-23 16:09:58 -08:00
Xiaoliang Yang
ae2778a647 net: dsa: tag_ocelot: use traffic class to map priority on injected header
For Ocelot switches, the CPU injected frames have an injection header
where it can specify the QoS class of the packet and the DSA tag, now it
uses the SKB priority to set that. If a traffic class to priority
mapping is configured on the netdevice (with mqprio for example ...), it
won't be considered for CPU injected headers. This patch make the QoS
class aligned to the priority to traffic class mapping if it exists.

Fixes: 8dce89aa5f ("net: dsa: ocelot: add tagger for Ocelot/Felix switches")
Signed-off-by: Xiaoliang Yang <xiaoliang.yang_1@nxp.com>
Signed-off-by: Marouen Ghodhbane <marouen.ghodhbane@nxp.com>
Link: https://lore.kernel.org/r/20211223072211.33130-1-xiaoliang.yang_1@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-23 09:44:59 -08:00
Vladimir Oltean
7f2973149c net: dsa: make tagging protocols connect to individual switches from a tree
On the NXP Bluebox 3 board which uses a multi-switch setup with sja1105,
the mechanism through which the tagger connects to the switch tree is
broken, due to improper DSA code design. At the time when tag_ops->connect()
is called in dsa_port_parse_cpu(), DSA hasn't finished "touching" all
the ports, so it doesn't know how large the tree is and how many ports
it has. It has just seen the first CPU port by this time. As a result,
this function will call the tagger's ->connect method too early, and the
tagger will connect only to the first switch from the tree.

This could be perhaps addressed a bit more simply by just moving the
tag_ops->connect(dst) call a bit later (for example in dsa_tree_setup),
but there is already a design inconsistency at present: on the switch
side, the notification is on a per-switch basis, but on the tagger side,
it is on a per-tree basis. Furthermore, the persistent storage itself is
per switch (ds->tagger_data). And the tagger connect and disconnect
procedures (at least the ones that exist currently) could see a fair bit
of simplification if they didn't have to iterate through the switches of
a tree.

To fix the issue, this change transforms tag_ops->connect(dst) into
tag_ops->connect(ds) and moves it somewhere where we already iterate
over all switches of a tree. That is in dsa_switch_setup_tag_protocol(),
which is a good placement because we already have there the connection
call to the switch side of things.

As for the dsa_tree_bind_tag_proto() method (called from the code path
that changes the tag protocol), things are a bit more complicated
because we receive the tree as argument, yet when we unwind on errors,
it would be nice to not call tag_ops->disconnect(ds) where we didn't
previously call tag_ops->connect(ds). We didn't have this problem before
because the tag_ops connection operations passed the entire dst before,
and this is more fine grained now. To solve the error rewind case using
the new API, we have to create yet one more cross-chip notifier for
disconnection, and stay connected with the old tag protocol to all the
switches in the tree until we've succeeded to connect with the new one
as well. So if something fails half way, the whole tree is still
connected to the old tagger. But there may still be leaks if the tagger
fails to connect to the 2nd out of 3 switches in a tree: somebody needs
to tell the tagger to disconnect from the first switch. Nothing comes
for free, and this was previously handled privately by the tagging
protocol driver before, but now we need to emit a disconnect cross-chip
notifier for that, because DSA has to take care of the unwind path. We
assume that the tagging protocol has connected to a switch if it has set
ds->tagger_data to something, otherwise we avoid calling its
disconnection method in the error rewind path.

The rest of the changes are in the tagging protocol drivers, and have to
do with the replacement of dst with ds. The iteration is removed and the
error unwind path is simplified, as mentioned above.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-14 12:45:16 +00:00
Vladimir Oltean
e2f01bfe14 net: dsa: tag_sja1105: fix zeroization of ds->priv on tag proto disconnect
The method was meant to zeroize ds->tagger_data but got the wrong
pointer. Fix this.

Fixes: c79e84866d ("net: dsa: tag_sja1105: convert to tagger-owned data")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-14 12:45:15 +00:00
Vladimir Oltean
950a419d9d net: dsa: tag_sja1105: split sja1105_tagger_data into private and public sections
The sja1105 driver messes with the tagging protocol's state when PTP RX
timestamping is enabled/disabled. This is fundamentally necessary
because the tagger needs to know what to do when it receives a PTP
packet. If RX timestamping is enabled, then a metadata follow-up frame
is expected, and this holds the (partial) timestamp. So the tagger plays
hide-and-seek with the network stack until it also gets the metadata
frame, and then presents a single packet, the timestamped PTP packet.
But when RX timestamping isn't enabled, there is no metadata frame
expected, so the hide-and-seek game must be turned off and the packet
must be delivered right away to the network stack.

Considering this, we create a pseudo isolation by devising two tagger
methods callable by the switch: one to get the RX timestamping state,
and one to set it. Since we can't export symbols between the tagger and
the switch driver, these methods are exposed through function pointers.

After this change, the public portion of the sja1105_tagger_data
contains only function pointers.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12 12:51:34 +00:00
Vladimir Oltean
fcbf979a5b Revert "net: dsa: move sja1110_process_meta_tstamp inside the tagging protocol driver"
This reverts commit 6d709cadfd.

The above change was done to avoid calling symbols exported by the
switch driver from the tagging protocol driver.

With the tagger-owned storage model, we have a new option on our hands,
and that is for the switch driver to provide a data consumer handler in
the form of a function pointer inside the ->connect_tag_protocol()
method. Having a function pointer avoids the problems of the exported
symbols approach.

By creating a handler for metadata frames holding TX timestamps on
SJA1110, we are able to eliminate an skb queue from the tagger data, and
replace it with a simple, and stateless, function pointer. This skb
queue is now handled exclusively by sja1105_ptp.c, which makes the code
easier to follow, as it used to be before the reverted patch.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12 12:51:34 +00:00
Vladimir Oltean
c79e84866d net: dsa: tag_sja1105: convert to tagger-owned data
Currently, struct sja1105_tagger_data is a part of struct
sja1105_private, and is used by the sja1105 driver to populate dp->priv.

With the movement towards tagger-owned storage, the sja1105 driver
should not be the owner of this memory.

This change implements the connection between the sja1105 switch driver
and its tagging protocol, which means that sja1105_tagger_data no longer
stays in dp->priv but in ds->tagger_data, and that the sja1105 driver
now only populates the sja1105_port_deferred_xmit callback pointer.
The kthread worker is now the responsibility of the tagger.

The sja1105 driver also alters the tagger's state some more, especially
with regard to the PTP RX timestamping state. This will be fixed up a
bit in further changes.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12 12:51:33 +00:00
Vladimir Oltean
bfcf142522 net: dsa: sja1105: make dp->priv point directly to sja1105_tagger_data
The design of the sja1105 tagger dp->priv is that each port has a
separate struct sja1105_port, and the sp->data pointer points to a
common struct sja1105_tagger_data.

We have removed all per-port members accessible by the tagger, and now
only struct sja1105_tagger_data remains. Make dp->priv point directly to
this.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12 12:51:33 +00:00
Vladimir Oltean
d38049bbe7 net: dsa: sja1105: bring deferred xmit implementation in line with ocelot-8021q
When the ocelot-8021q driver was converted to deferred xmit as part of
commit 8d5f7954b7 ("net: dsa: felix: break at first CPU port during
init and teardown"), the deferred implementation was deliberately made
subtly different from what sja1105 has.

The implementation differences lied on the following observations:

- There might be a race between these two lines in tag_sja1105.c:

       skb_queue_tail(&sp->xmit_queue, skb_get(skb));
       kthread_queue_work(sp->xmit_worker, &sp->xmit_work);

  and the skb dequeue logic in sja1105_port_deferred_xmit(). For
  example, the xmit_work might be already queued, however the work item
  has just finished walking through the skb queue. Because we don't
  check the return code from kthread_queue_work, we don't do anything if
  the work item is already queued.

  However, nobody will take that skb and send it, at least until the
  next timestampable skb is sent. This creates additional (and
  avoidable) TX timestamping latency.

  To close that race, what the ocelot-8021q driver does is it doesn't
  keep a single work item per port, and a skb timestamping queue, but
  rather dynamically allocates a work item per packet.

- It is also unnecessary to have more than one kthread that does the
  work. So delete the per-port kthread allocations and replace them with
  a single kthread which is global to the switch.

This change brings the two implementations in line by applying those
observations to the sja1105 driver as well.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12 12:51:33 +00:00
Vladimir Oltean
35d9768021 net: dsa: tag_ocelot: convert to tagger-owned data
The felix driver makes very light use of dp->priv, and the tagger is
effectively stateless. dp->priv is practically only needed to set up a
callback to perform deferred xmit of PTP and STP packets using the
ocelot-8021q tagging protocol (the main ocelot tagging protocol makes no
use of dp->priv, although this driver sets up dp->priv irrespective of
actual tagging protocol in use).

struct felix_port (what used to be pointed to by dp->priv) is removed
and replaced with a two-sided structure. The public side of this
structure, visible to the switch driver, is ocelot_8021q_tagger_data.
The private side is ocelot_8021q_tagger_private, and the latter
structure physically encapsulates the former. The public half of the
tagger data structure can be accessed through a helper of the same name
(ocelot_8021q_tagger_data) which also sanity-checks the protocol
currently in use by the switch. The public/private split was requested
by Andrew Lunn.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12 12:51:33 +00:00
Vladimir Oltean
dc452a471d net: dsa: introduce tagger-owned storage for private and shared data
Ansuel is working on register access over Ethernet for the qca8k switch
family. This requires the qca8k tagging protocol driver to receive
frames which aren't intended for the network stack, but instead for the
qca8k switch driver itself.

The dp->priv is currently the prevailing method for passing data back
and forth between the tagging protocol driver and the switch driver.
However, this method is riddled with caveats.

The DSA design allows in principle for any switch driver to return any
protocol it desires in ->get_tag_protocol(). The dsa_loop driver can be
modified to do just that. But in the current design, the memory behind
dp->priv has to be allocated by the switch driver, so if the tagging
protocol is paired to an unexpected switch driver, we may end up in NULL
pointer dereferences inside the kernel, or worse (a switch driver may
allocate dp->priv according to the expectations of a different tagger).

The latter possibility is even more plausible considering that DSA
switches can dynamically change tagging protocols in certain cases
(dsa <-> edsa, ocelot <-> ocelot-8021q), and the current design lends
itself to mistakes that are all too easy to make.

This patch proposes that the tagging protocol driver should manage its
own memory, instead of relying on the switch driver to do so.
After analyzing the different in-tree needs, it can be observed that the
required tagger storage is per switch, therefore a ds->tagger_data
pointer is introduced. In principle, per-port storage could also be
introduced, although there is no need for it at the moment. Future
changes will replace the current usage of dp->priv with ds->tagger_data.

We define a "binding" event between the DSA switch tree and the tagging
protocol. During this binding event, the tagging protocol's ->connect()
method is called first, and this may allocate some memory for each
switch of the tree. Then a cross-chip notifier is emitted for the
switches within that tree, and they are given the opportunity to fix up
the tagger's memory (for example, they might set up some function
pointers that represent virtual methods for consuming packets).
Because the memory is owned by the tagger, there exists a ->disconnect()
method for the tagger (which is the place to free the resources), but
there doesn't exist a ->disconnect() method for the switch driver.
This is part of the design. The switch driver should make minimal use of
the public part of the tagger data, and only after type-checking it
using the supplied "proto" argument.

In the code there are in fact two binding events, one is the initial
event in dsa_switch_setup_tag_protocol(). At this stage, the cross chip
notifier chains aren't initialized, so we call each switch's connect()
method by hand. Then there is dsa_tree_bind_tag_proto() during
dsa_tree_change_tag_proto(), and here we have an old protocol and a new
one. We first connect to the new one before disconnecting from the old
one, to simplify error handling a bit and to ensure we remain in a valid
state at all times.

Co-developed-by: Ansuel Smith <ansuelsmth@gmail.com>
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12 12:51:33 +00:00