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  1. 24 10月, 2021 1 次提交
    • S
      net: convert users of bitmap_foo() to linkmode_foo() · 4973056c
      由 Sean Anderson 提交于 
      This converts instances of
	bitmap_foo(args..., __ETHTOOL_LINK_MODE_MASK_NBITS)
to
	linkmode_foo(args...)

I manually fixed up some lines to prevent them from being excessively
long. Otherwise, this change was generated with the following semantic
patch:

// Generated with
// echo linux/linkmode.h > includes
// git grep -Flf includes include/ | cut -f 2- -d / | cat includes - \
// | sort | uniq | tee new_includes | wc -l && mv new_includes includes
// and repeating until the number stopped going up
@i@
@@

(
 #include <linux/acpi_mdio.h>
|
 #include <linux/brcmphy.h>
|
 #include <linux/dsa/loop.h>
|
 #include <linux/dsa/sja1105.h>
|
 #include <linux/ethtool.h>
|
 #include <linux/ethtool_netlink.h>
|
 #include <linux/fec.h>
|
 #include <linux/fs_enet_pd.h>
|
 #include <linux/fsl/enetc_mdio.h>
|
 #include <linux/fwnode_mdio.h>
|
 #include <linux/linkmode.h>
|
 #include <linux/lsm_audit.h>
|
 #include <linux/mdio-bitbang.h>
|
 #include <linux/mdio.h>
|
 #include <linux/mdio-mux.h>
|
 #include <linux/mii.h>
|
 #include <linux/mii_timestamper.h>
|
 #include <linux/mlx5/accel.h>
|
 #include <linux/mlx5/cq.h>
|
 #include <linux/mlx5/device.h>
|
 #include <linux/mlx5/driver.h>
|
 #include <linux/mlx5/eswitch.h>
|
 #include <linux/mlx5/fs.h>
|
 #include <linux/mlx5/port.h>
|
 #include <linux/mlx5/qp.h>
|
 #include <linux/mlx5/rsc_dump.h>
|
 #include <linux/mlx5/transobj.h>
|
 #include <linux/mlx5/vport.h>
|
 #include <linux/of_mdio.h>
|
 #include <linux/of_net.h>
|
 #include <linux/pcs-lynx.h>
|
 #include <linux/pcs/pcs-xpcs.h>
|
 #include <linux/phy.h>
|
 #include <linux/phy_led_triggers.h>
|
 #include <linux/phylink.h>
|
 #include <linux/platform_data/bcmgenet.h>
|
 #include <linux/platform_data/xilinx-ll-temac.h>
|
 #include <linux/pxa168_eth.h>
|
 #include <linux/qed/qed_eth_if.h>
|
 #include <linux/qed/qed_fcoe_if.h>
|
 #include <linux/qed/qed_if.h>
|
 #include <linux/qed/qed_iov_if.h>
|
 #include <linux/qed/qed_iscsi_if.h>
|
 #include <linux/qed/qed_ll2_if.h>
|
 #include <linux/qed/qed_nvmetcp_if.h>
|
 #include <linux/qed/qed_rdma_if.h>
|
 #include <linux/sfp.h>
|
 #include <linux/sh_eth.h>
|
 #include <linux/smsc911x.h>
|
 #include <linux/soc/nxp/lpc32xx-misc.h>
|
 #include <linux/stmmac.h>
|
 #include <linux/sunrpc/svc_rdma.h>
|
 #include <linux/sxgbe_platform.h>
|
 #include <net/cfg80211.h>
|
 #include <net/dsa.h>
|
 #include <net/mac80211.h>
|
 #include <net/selftests.h>
|
 #include <rdma/ib_addr.h>
|
 #include <rdma/ib_cache.h>
|
 #include <rdma/ib_cm.h>
|
 #include <rdma/ib_hdrs.h>
|
 #include <rdma/ib_mad.h>
|
 #include <rdma/ib_marshall.h>
|
 #include <rdma/ib_pack.h>
|
 #include <rdma/ib_pma.h>
|
 #include <rdma/ib_sa.h>
|
 #include <rdma/ib_smi.h>
|
 #include <rdma/ib_umem.h>
|
 #include <rdma/ib_umem_odp.h>
|
 #include <rdma/ib_verbs.h>
|
 #include <rdma/iw_cm.h>
|
 #include <rdma/mr_pool.h>
|
 #include <rdma/opa_addr.h>
|
 #include <rdma/opa_port_info.h>
|
 #include <rdma/opa_smi.h>
|
 #include <rdma/opa_vnic.h>
|
 #include <rdma/rdma_cm.h>
|
 #include <rdma/rdma_cm_ib.h>
|
 #include <rdma/rdmavt_cq.h>
|
 #include <rdma/rdma_vt.h>
|
 #include <rdma/rdmavt_qp.h>
|
 #include <rdma/rw.h>
|
 #include <rdma/tid_rdma_defs.h>
|
 #include <rdma/uverbs_ioctl.h>
|
 #include <rdma/uverbs_named_ioctl.h>
|
 #include <rdma/uverbs_std_types.h>
|
 #include <rdma/uverbs_types.h>
|
 #include <soc/mscc/ocelot.h>
|
 #include <soc/mscc/ocelot_ptp.h>
|
 #include <soc/mscc/ocelot_vcap.h>
|
 #include <trace/events/ib_mad.h>
|
 #include <trace/events/rdma_core.h>
|
 #include <trace/events/rdma.h>
|
 #include <trace/events/rpcrdma.h>
|
 #include <uapi/linux/ethtool.h>
|
 #include <uapi/linux/ethtool_netlink.h>
|
 #include <uapi/linux/mdio.h>
|
 #include <uapi/linux/mii.h>
)

@depends on i@
expression list args;
@@

(
- bitmap_zero(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_zero(args)
|
- bitmap_copy(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_copy(args)
|
- bitmap_and(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_and(args)
|
- bitmap_or(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_or(args)
|
- bitmap_empty(args, ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_empty(args)
|
- bitmap_andnot(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_andnot(args)
|
- bitmap_equal(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_equal(args)
|
- bitmap_intersects(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_intersects(args)
|
- bitmap_subset(args, __ETHTOOL_LINK_MODE_MASK_NBITS)
+ linkmode_subset(args)
)

Add missing linux/mii.h include to mellanox. -DaveM
Signed-off-by: NSean Anderson <sean.anderson@seco.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4973056c
  3. 12 10月, 2021 1 次提交
    • A
      net: dsa: microchip: Added the condition for scheduling ksz_mib_read_work · ef1100ef
      由 Arun Ramadoss 提交于 
      When the ksz module is installed and removed using rmmod, kernel crashes
with null pointer dereferrence error. During rmmod, ksz_switch_remove
function tries to cancel the mib_read_workqueue using
cancel_delayed_work_sync routine and unregister switch from dsa.

During dsa_unregister_switch it calls ksz_mac_link_down, which in turn
reschedules the workqueue since mib_interval is non-zero.
Due to which queue executed after mib_interval and it tries to access
dp->slave. But the slave is unregistered in the ksz_switch_remove
function. Hence kernel crashes.

To avoid this crash, before canceling the workqueue, resetted the
mib_interval to 0.

v1 -> v2:
-Removed the if condition in ksz_mib_read_work

Fixes: 469b390e ("net: dsa: microchip: use delayed_work instead of timer + work")
Signed-off-by: NArun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ef1100ef
  5. 19 9月, 2021 2 次提交
    • V
      net: dsa: microchip: ksz8863: be compatible with masters which unregister on shutdown · fe405307
      由 Vladimir Oltean 提交于 
      Since commit 2f1e8ea7 ("net: dsa: link interfaces with the DSA
master to get rid of lockdep warnings"), DSA gained a requirement which
it did not fulfill, which is to unlink itself from the DSA master at
shutdown time.

Since the Microchip sub-driver for KSZ8863 was introduced after the bad
commit, it has never worked with DSA masters which decide to unregister
their net_device on shutdown, effectively hanging the reboot process.
To fix that, we need to call dsa_switch_shutdown.

Since this driver expects the MDIO bus to be backed by mdio_bitbang, I
don't think there is currently any MDIO bus driver which implements its
->shutdown by redirecting it to ->remove, but in any case, to be
compatible with that pattern, it is necessary to implement an "if this
then not that" scheme, to avoid ->remove and ->shutdown from being
called both for the same struct device.

Fixes: 60a36476 ("net: dsa: microchip: Add Microchip KSZ8863 SMI based driver support")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/Reported-by: NLino Sanfilippo <LinoSanfilippo@gmx.de>
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>
      fe405307
    • V
      net: dsa: be compatible with masters which unregister on shutdown · 0650bf52
      由 Vladimir Oltean 提交于 
      Lino reports that on his system with bcmgenet as DSA master and KSZ9897
as a switch, rebooting or shutting down never works properly.

What does the bcmgenet driver have special to trigger this, that other
DSA masters do not? It has an implementation of ->shutdown which simply
calls its ->remove implementation. Otherwise said, it unregisters its
network interface on shutdown.

This message can be seen in a loop, and it hangs the reboot process there:

unregister_netdevice: waiting for eth0 to become free. Usage count = 3

So why 3?

A usage count of 1 is normal for a registered network interface, and any
virtual interface which links itself as an upper of that will increment
it via dev_hold. In the case of DSA, this is the call path:

dsa_slave_create
-> netdev_upper_dev_link
   -> __netdev_upper_dev_link
      -> __netdev_adjacent_dev_insert
         -> dev_hold

So a DSA switch with 3 interfaces will result in a usage count elevated
by two, and netdev_wait_allrefs will wait until they have gone away.

Other stacked interfaces, like VLAN, watch NETDEV_UNREGISTER events and
delete themselves, but DSA cannot just vanish and go poof, at most it
can unbind itself from the switch devices, but that must happen strictly
earlier compared to when the DSA master unregisters its net_device, so
reacting on the NETDEV_UNREGISTER event is way too late.

It seems that it is a pretty established pattern to have a driver's
->shutdown hook redirect to its ->remove hook, so the same code is
executed regardless of whether the driver is unbound from the device, or
the system is just shutting down. As Florian puts it, it is quite a big
hammer for bcmgenet to unregister its net_device during shutdown, but
having a common code path with the driver unbind helps ensure it is well
tested.

So DSA, for better or for worse, has to live with that and engage in an
arms race of implementing the ->shutdown hook too, from all individual
drivers, and do something sane when paired with masters that unregister
their net_device there. The only sane thing to do, of course, is to
unlink from the master.

However, complications arise really quickly.

The pattern of redirecting ->shutdown to ->remove is not unique to
bcmgenet or even to net_device drivers. In fact, SPI controllers do it
too (see dspi_shutdown -> dspi_remove), and presumably, I2C controllers
and MDIO controllers do it too (this is something I have not researched
too deeply, but even if this is not the case today, it is certainly
plausible to happen in the future, and must be taken into consideration).

Since DSA switches might be SPI devices, I2C devices, MDIO devices, the
insane implication is that for the exact same DSA switch device, we
might have both ->shutdown and ->remove getting called.

So we need to do something with that insane environment. The pattern
I've come up with is "if this, then not that", so if either ->shutdown
or ->remove gets called, we set the device's drvdata to NULL, and in the
other hook, we check whether the drvdata is NULL and just do nothing.
This is probably not necessary for platform devices, just for devices on
buses, but I would really insist for consistency among drivers, because
when code is copy-pasted, it is not always copy-pasted from the best
sources.

So depending on whether the DSA switch's ->remove or ->shutdown will get
called first, we cannot really guarantee even for the same driver if
rebooting will result in the same code path on all platforms. But
nonetheless, we need to do something minimally reasonable on ->shutdown
too to fix the bug. Of course, the ->remove will do more (a full
teardown of the tree, with all data structures freed, and this is why
the bug was not caught for so long). The new ->shutdown method is kept
separate from dsa_unregister_switch not because we couldn't have
unregistered the switch, but simply in the interest of doing something
quick and to the point.

The big question is: does the DSA switch's ->shutdown get called earlier
than the DSA master's ->shutdown? If not, there is still a risk that we
might still trigger the WARN_ON in unregister_netdevice that says we are
attempting to unregister a net_device which has uppers. That's no good.
Although the reference to the master net_device won't physically go away
even if DSA's ->shutdown comes afterwards, remember we have a dev_hold
on it.

The answer to that question lies in this comment above device_link_add:

 * A side effect of the link creation is re-ordering of dpm_list and the
 * devices_kset list by moving the consumer device and all devices depending
 * on it to the ends of these lists (that does not happen to devices that have
 * not been registered when this function is called).

so the fact that DSA uses device_link_add towards its master is not
exactly for nothing. device_shutdown() walks devices_kset from the back,
so this is our guarantee that DSA's shutdown happens before the master's
shutdown.

Fixes: 2f1e8ea7 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/Reported-by: NLino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0650bf52
  7. 10 8月, 2021 7 次提交
  9. 12 7月, 2021 1 次提交
  11. 15 6月, 2021 5 次提交
  13. 25 5月, 2021 1 次提交
  15. 30 4月, 2021 3 次提交
  17. 29 4月, 2021 1 次提交
  19. 28 4月, 2021 6 次提交
  21. 15 2月, 2021 2 次提交
  23. 21 1月, 2021 2 次提交
  25. 16 1月, 2021 1 次提交
    • V
      net: dsa: set configure_vlan_while_not_filtering to true by default · 0ee2af4e
      由 Vladimir Oltean 提交于 
      As explained in commit 54a0ed0d ("net: dsa: provide an option for
drivers to always receive bridge VLANs"), DSA has historically been
skipping VLAN switchdev operations when the bridge wasn't in
vlan_filtering mode, but the reason why it was doing that has never been
clear. So the configure_vlan_while_not_filtering option is there merely
to preserve functionality for existing drivers. It isn't some behavior
that drivers should opt into. Ideally, when all drivers leave this flag
set, we can delete the dsa_port_skip_vlan_configuration() function.

New drivers always seem to omit setting this flag, for some reason. So
let's reverse the logic: the DSA core sets it by default to true before
the .setup() callback, and legacy drivers can turn it off. This way, new
drivers get the new behavior by default, unless they explicitly set the
flag to false, which is more obvious during review.

Remove the assignment from drivers which were setting it to true, and
add the assignment to false for the drivers that didn't previously have
it. This way, it should be easier to see how many we have left.

The following drivers: lan9303, mv88e6060 were skipped from setting this
flag to false, because they didn't have any VLAN offload ops in the
first place.

The Broadcom Starfighter 2 driver calls the common b53_switch_alloc and
therefore also inherits the configure_vlan_while_not_filtering=true
behavior.

Also, print a message through netlink extack every time a VLAN has been
skipped. This is mildly annoying on purpose, so that (a) it is at least
clear that VLANs are being skipped - the legacy behavior in itself is
confusing, and the extack should be much more difficult to miss, unlike
kernel logs - and (b) people have one more incentive to convert to the
new behavior.

No behavior change except for the added prints is intended at this time.

$ ip link add br0 type bridge vlan_filtering 0
$ ip link set sw0p2 master br0
[   60.315148] br0: port 1(sw0p2) entered blocking state
[   60.320350] br0: port 1(sw0p2) entered disabled state
[   60.327839] device sw0p2 entered promiscuous mode
[   60.334905] br0: port 1(sw0p2) entered blocking state
[   60.340142] br0: port 1(sw0p2) entered forwarding state
Warning: dsa_core: skipping configuration of VLAN. # This was the pvid
$ bridge vlan add dev sw0p2 vid 100
Warning: dsa_core: skipping configuration of VLAN.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NKurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210115231919.43834-1-vladimir.oltean@nxp.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>
      0ee2af4e
  27. 12 1月, 2021 4 次提交
    • V
      net: dsa: remove the transactional logic from VLAN objects · 1958d581
      由 Vladimir Oltean 提交于 
      It should be the driver's business to logically separate its VLAN
offloading into a preparation and a commit phase, and some drivers don't
need / can't do this.

So remove the transactional shim from DSA and let drivers propagate
errors directly from the .port_vlan_add callback.

It would appear that the code has worse error handling now than it had
before. DSA is the only in-kernel user of switchdev that offloads one
switchdev object to more than one port: for every VLAN object offloaded
to a user port, that VLAN is also offloaded to the CPU port. So the
"prepare for user port -> check for errors -> prepare for CPU port ->
check for errors -> commit for user port -> commit for CPU port"
sequence appears to make more sense than the one we are using now:
"offload to user port -> check for errors -> offload to CPU port ->
check for errors", but it is really a compromise. In the new way, we can
catch errors from the commit phase that we previously had to ignore.
But we have our hands tied and cannot do any rollback now: if we add a
VLAN on the CPU port and it fails, we can't do the rollback by simply
deleting it from the user port, because the switchdev API is not so nice
with us: it could have simply been there already, even with the same
flags. So we don't even attempt to rollback anything on addition error,
just leave whatever VLANs managed to get offloaded right where they are.
This should not be a problem at all in practice.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJiri Pirko <jiri@nvidia.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
      1958d581
    • V
      net: dsa: remove the transactional logic from MDB entries · a52b2da7
      由 Vladimir Oltean 提交于 
      For many drivers, the .port_mdb_prepare callback was not a good opportunity
to avoid any error condition, and they would suppress errors found during
the actual commit phase.

Where a logical separation between the prepare and the commit phase
existed, the function that used to implement the .port_mdb_prepare
callback still exists, but now it is called directly from .port_mdb_add,
which was modified to return an int code.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJiri Pirko <jiri@nvidia.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek
Reviewed-by: Linus Wallei <linus.walleij@linaro.org> # RTL8366
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
      a52b2da7
    • V
      net: switchdev: remove the transaction structure from port attributes · bae33f2b
      由 Vladimir Oltean 提交于 
      Since the introduction of the switchdev API, port attributes were
transmitted to drivers for offloading using a two-step transactional
model, with a prepare phase that was supposed to catch all errors, and a
commit phase that was supposed to never fail.

Some classes of failures can never be avoided, like hardware access, or
memory allocation. In the latter case, merely attempting to move the
memory allocation to the preparation phase makes it impossible to avoid
memory leaks, since commit 91cf8ece ("switchdev: Remove unused
transaction item queue") which has removed the unused mechanism of
passing on the allocated memory between one phase and another.

It is time we admit that separating the preparation from the commit
phase is something that is best left for the driver to decide, and not
something that should be baked into the API, especially since there are
no switchdev callers that depend on this.

This patch removes the struct switchdev_trans member from switchdev port
attribute notifier structures, and converts drivers to not look at this
member.

In part, this patch contains a revert of my previous commit 2e554a7a
("net: dsa: propagate switchdev vlan_filtering prepare phase to
drivers").

For the most part, the conversion was trivial except for:
- Rocker's world implementation based on Broadcom OF-DPA had an odd
  implementation of ofdpa_port_attr_bridge_flags_set. The conversion was
  done mechanically, by pasting the implementation twice, then only
  keeping the code that would get executed during prepare phase on top,
  then only keeping the code that gets executed during the commit phase
  on bottom, then simplifying the resulting code until this was obtained.
- DSA's offloading of STP state, bridge flags, VLAN filtering and
  multicast router could be converted right away. But the ageing time
  could not, so a shim was introduced and this was left for a further
  commit.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJiri Pirko <jiri@nvidia.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek
Reviewed-by: Linus Walleij <linus.walleij@linaro.org> # RTL8366RB
Reviewed-by: NIdo Schimmel <idosch@nvidia.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
      bae33f2b
    • V
      net: switchdev: remove vid_begin -> vid_end range from VLAN objects · b7a9e0da
      由 Vladimir Oltean 提交于 
      The call path of a switchdev VLAN addition to the bridge looks something
like this today:

        nbp_vlan_init
        |  __br_vlan_set_default_pvid
        |  |                       |
        |  |    br_afspec          |
        |  |        |              |
        |  |        v              |
        |  | br_process_vlan_info  |
        |  |        |              |
        |  |        v              |
        |  |   br_vlan_info        |
        |  |       / \            /
        |  |      /   \          /
        |  |     /     \        /
        |  |    /       \      /
        v  v   v         v    v
      nbp_vlan_add   br_vlan_add ------+
       |              ^      ^ |       |
       |             /       | |       |
       |            /       /  /       |
       \ br_vlan_get_master/  /        v
        \        ^        /  /  br_vlan_add_existing
         \       |       /  /          |
          \      |      /  /          /
           \     |     /  /          /
            \    |    /  /          /
             \   |   /  /          /
              v  |   | v          /
              __vlan_add         /
                 / |            /
                /  |           /
               v   |          /
   __vlan_vid_add  |         /
               \   |        /
                v  v        v
      br_switchdev_port_vlan_add

The ranges UAPI was introduced to the bridge in commit bdced7ef
("bridge: support for multiple vlans and vlan ranges in setlink and
dellink requests") (Jan 10 2015). But the VLAN ranges (parsed in br_afspec)
have always been passed one by one, through struct bridge_vlan_info
tmp_vinfo, to br_vlan_info. So the range never went too far in depth.

Then Scott Feldman introduced the switchdev_port_bridge_setlink function
in commit 47f8328b ("switchdev: add new switchdev bridge setlink").
That marked the introduction of the SWITCHDEV_OBJ_PORT_VLAN, which made
full use of the range. But switchdev_port_bridge_setlink was called like
this:

br_setlink
-> br_afspec
-> switchdev_port_bridge_setlink

Basically, the switchdev and the bridge code were not tightly integrated.
Then commit 41c498b9 ("bridge: restore br_setlink back to original")
came, and switchdev drivers were required to implement
.ndo_bridge_setlink = switchdev_port_bridge_setlink for a while.

In the meantime, commits such as 0944d6b5 ("bridge: try switchdev op
first in __vlan_vid_add/del") finally made switchdev penetrate the
br_vlan_info() barrier and start to develop the call path we have today.
But remember, br_vlan_info() still receives VLANs one by one.

Then Arkadi Sharshevsky refactored the switchdev API in 2017 in commit
29ab586c ("net: switchdev: Remove bridge bypass support from
switchdev") so that drivers would not implement .ndo_bridge_setlink any
longer. The switchdev_port_bridge_setlink also got deleted.
This refactoring removed the parallel bridge_setlink implementation from
switchdev, and left the only switchdev VLAN objects to be the ones
offloaded from __vlan_vid_add (basically RX filtering) and  __vlan_add
(the latter coming from commit 9c86ce2c ("net: bridge: Notify about
bridge VLANs")).

That is to say, today the switchdev VLAN object ranges are not used in
the kernel. Refactoring the above call path is a bit complicated, when
the bridge VLAN call path is already a bit complicated.

Let's go off and finish the job of commit 29ab586c by deleting the
bogus iteration through the VLAN ranges from the drivers. Some aspects
of this feature never made too much sense in the first place. For
example, what is a range of VLANs all having the BRIDGE_VLAN_INFO_PVID
flag supposed to mean, when a port can obviously have a single pvid?
This particular configuration _is_ denied as of commit 6623c60d
("bridge: vlan: enforce no pvid flag in vlan ranges"), but from an API
perspective, the driver still has to play pretend, and only offload the
vlan->vid_end as pvid. And the addition of a switchdev VLAN object can
modify the flags of another, completely unrelated, switchdev VLAN
object! (a VLAN that is PVID will invalidate the PVID flag from whatever
other VLAN had previously been offloaded with switchdev and had that
flag. Yet switchdev never notifies about that change, drivers are
supposed to guess).

Nonetheless, having a VLAN range in the API makes error handling look
scarier than it really is - unwinding on errors and all of that.
When in reality, no one really calls this API with more than one VLAN.
It is all unnecessary complexity.

And despite appearing pretentious (two-phase transactional model and
all), the switchdev API is really sloppy because the VLAN addition and
removal operations are not paired with one another (you can add a VLAN
100 times and delete it just once). The bridge notifies through
switchdev of a VLAN addition not only when the flags of an existing VLAN
change, but also when nothing changes. There are switchdev drivers out
there who don't like adding a VLAN that has already been added, and
those checks don't really belong at driver level. But the fact that the
API contains ranges is yet another factor that prevents this from being
addressed in the future.

Of the existing switchdev pieces of hardware, it appears that only
Mellanox Spectrum supports offloading more than one VLAN at a time,
through mlxsw_sp_port_vlan_set. I have kept that code internal to the
driver, because there is some more bookkeeping that makes use of it, but
I deleted it from the switchdev API. But since the switchdev support for
ranges has already been de facto deleted by a Mellanox employee and
nobody noticed for 4 years, I'm going to assume it's not a biggie.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com> # switchdev and mlxsw
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
      b7a9e0da
  29. 03 12月, 2020 3 次提交