1. 25 10月, 2021 6 次提交
    • V
      net: dsa: lantiq_gswip: serialize access to the PCE registers · cf231b43
      Vladimir Oltean 提交于
      The GSWIP switch accesses various bridging layer tables (VLANs, FDBs,
      forwarding rules) indirectly through PCE registers. These hardware
      accesses are non-atomic, being comprised of several register reads and
      writes.
      
      These accesses are currently serialized by the rtnl_lock, but DSA is
      changing its driver API and that lock will no longer be held when
      calling ->port_fdb_add() and ->port_fdb_del().
      
      So this driver needs to serialize the access to the PCE registers using
      its own locking scheme. This patch adds that.
      
      Note that the driver also uses the gswip_pce_load_microcode() function
      to load a static configuration for the packet classification engine into
      a table using the same registers. It is currently not protected, but
      since that configuration is only done from the dsa_switch_ops :: setup
      method, there is no risk of it being concurrent with other operations.
      Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
      Acked-by: NHauke Mehrtens <hauke@hauke-m.de>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cf231b43
    • V
      net: dsa: b53: serialize access to the ARL table · f7eb4a1c
      Vladimir Oltean 提交于
      The b53 driver performs non-atomic transactions to the ARL table when
      adding, deleting and reading FDB and MDB entries.
      
      Traditionally these were all serialized by the rtnl_lock(), but now it
      is possible that DSA calls ->port_fdb_add and ->port_fdb_del without
      holding that lock.
      
      So the driver must have its own serialization logic. Add a mutex and
      hold it from all entry points (->port_fdb_{add,del,dump},
      ->port_mdb_{add,del}).
      Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
      Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f7eb4a1c
    • V
      net: mscc: ocelot: serialize access to the MAC table · 2468346c
      Vladimir Oltean 提交于
      DSA would like to remove the rtnl_lock from its
      SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE handlers, and the felix driver uses
      the same MAC table functions as ocelot.
      
      This means that the MAC table functions will no longer be implicitly
      serialized with respect to each other by the rtnl_mutex, we need to add
      a dedicated lock in ocelot for the non-atomic operations of selecting a
      MAC table row, reading/writing what we want and polling for completion.
      Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
      Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2468346c
    • V
      net: dsa: sja1105: serialize access to the dynamic config interface · eb016afd
      Vladimir Oltean 提交于
      The sja1105 hardware seems as concurrent as can be, but when we create a
      background script that adds/removes a rain of FDB entries without the
      rtnl_mutex taken, then in parallel we do another operation like run
      'bridge fdb show', we can notice these errors popping up:
      
      sja1105 spi2.0: port 2 failed to read back entry for 00:01:02:03:00:40 vid 0: -ENOENT
      sja1105 spi2.0: port 2 failed to add 00:01:02:03:00:40 vid 0 to fdb: -2
      sja1105 spi2.0: port 2 failed to read back entry for 00:01:02:03:00:46 vid 0: -ENOENT
      sja1105 spi2.0: port 2 failed to add 00:01:02:03:00:46 vid 0 to fdb: -2
      
      Luckily what is going on does not require a major rework in the driver.
      The sja1105_dynamic_config_read() function sends multiple SPI buffers to
      the peripheral until the operation completes. We should not do anything
      until the hardware clears the VALID bit.
      
      But since there is no locking (i.e. right now we are implicitly
      serialized by the rtnl_mutex, but if we remove that), it might be
      possible that the process which performs the dynamic config read is
      preempted and another one performs a dynamic config write.
      
      What will happen in that case is that sja1105_dynamic_config_read(),
      when it resumes, expects to see VALIDENT set for the entry it reads
      back. But it won't.
      
      This can be corrected by introducing a mutex for serializing SPI
      accesses to the dynamic config interface which should be atomic with
      respect to each other.
      Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
      Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      eb016afd
    • V
      net: dsa: sja1105: wait for dynamic config command completion on writes too · df405910
      Vladimir Oltean 提交于
      The hardware manual says that software should attempt a new dynamic
      config access (be it a a write or a read-back) only while the VALID bit
      is cleared. The VALID bit is set by software to 1, and it remains set as
      long as the hardware is still processing the request.
      
      Currently the driver only polls for the command completion only for
      reads, because that's when we need the actual data read back. Writes
      have been more or less "asynchronous", although this has never been an
      observable issue.
      
      This change makes sja1105_dynamic_config_write poll the VALID bit as
      well, to absolutely ensure that a follow-up access to the static config
      finds the VALID bit cleared.
      
      So VALID means "work in progress", while VALIDENT means "entry being
      read is valid". On reads we check the VALIDENT bit too, while on writes
      that bit is not always defined. So we need to factor it out of the loop,
      and make the loop provide back the unpacked command structure, so that
      sja1105_dynamic_config_read can check the VALIDENT bit.
      
      The change also attempts to convert the open-coded loop to use the
      read_poll_timeout macro, since I know this will come up during review.
      It's more code, but hey, it uses read_poll_timeout!
      
      Tested on SJA1105T, SJA1105S, SJA1110A.
      Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      df405910
    • D
      Revert "Merge branch 'dsa-rtnl'" · 2d7e73f0
      David S. Miller 提交于
      This reverts commit 965e6b26, reversing
      changes made to 4d98bb0d.
      2d7e73f0
  2. 24 10月, 2021 28 次提交
  3. 23 10月, 2021 6 次提交