| c4076cdd | 15-Feb-2022 |
Vladimir Oltean <vladimir.oltean@nxp.com> |
net: switchdev: introduce switchdev_handle_port_obj_{add,del} for foreign interfaces
The switchdev_handle_port_obj_add() helper is good for replicating a
port object on the lower interfaces of @dev,
net: switchdev: introduce switchdev_handle_port_obj_{add,del} for foreign interfaces
The switchdev_handle_port_obj_add() helper is good for replicating a
port object on the lower interfaces of @dev, if that object was emitted
on a bridge, or on a bridge port that is a LAG.
However, drivers that use this helper limit themselves to a box from
which they can no longer intercept port objects notified on neighbor
ports ("foreign interfaces").
One such driver is DSA, where software bridging with foreign interfaces
such as standalone NICs or Wi-Fi APs is an important use case. There, a
VLAN installed on a neighbor bridge port roughly corresponds to a
forwarding VLAN installed on the DSA switch's CPU port.
To support this use case while also making use of the benefits of the
switchdev_handle_* replication helper for port objects, introduce a new
variant of these functions that crawls through the neighbor ports of
@dev, in search of potentially compatible switchdev ports that are
interested in the event.
The strategy is identical to switchdev_handle_fdb_event_to_device():
if @dev wasn't a switchdev interface, then go one step upper, and
recursively call this function on the bridge that this port belongs to.
At the next recursion step, __switchdev_handle_port_obj_add() will
iterate through the bridge's lower interfaces. Among those, some will be
switchdev interfaces, and one will be the original @dev that we came
from. To prevent infinite recursion, we must suppress reentry into the
original @dev, and just call the @add_cb for the switchdev_interfaces.
It looks like this:
br0
/ | \
/ | \
/ | \
swp0 swp1 eth0
1. __switchdev_handle_port_obj_add(eth0)
-> check_cb(eth0) returns false
-> eth0 has no lower interfaces
-> eth0's bridge is br0
-> switchdev_lower_dev_find(br0, check_cb, foreign_dev_check_cb))
finds br0
2. __switchdev_handle_port_obj_add(br0)
-> check_cb(br0) returns false
-> netdev_for_each_lower_dev
-> check_cb(swp0) returns true, so we don't skip this interface
3. __switchdev_handle_port_obj_add(swp0)
-> check_cb(swp0) returns true, so we call add_cb(swp0)
(back to netdev_for_each_lower_dev from 2)
-> check_cb(swp1) returns true, so we don't skip this interface
4. __switchdev_handle_port_obj_add(swp1)
-> check_cb(swp1) returns true, so we call add_cb(swp1)
(back to netdev_for_each_lower_dev from 2)
-> check_cb(eth0) returns false, so we skip this interface to
avoid infinite recursion
Note: eth0 could have been a LAG, and we don't want to suppress the
recursion through its lowers if those exist, so when check_cb() returns
false, we still call switchdev_lower_dev_find() to estimate whether
there's anything worth a recursion beneath that LAG. Using check_cb()
and foreign_dev_check_cb(), switchdev_lower_dev_find() not only figures
out whether the lowers of the LAG are switchdev, but also whether they
actively offload the LAG or not (whether the LAG is "foreign" to the
switchdev interface or not).
The port_obj_info->orig_dev is preserved across recursive calls, so
switchdev drivers still know on which device was this notification
originally emitted.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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|
| 2b0a5688 | 22-Jul-2021 |
Vladimir Oltean <vladimir.oltean@nxp.com> |
net: switchdev: fix FDB entries towards foreign ports not getting propagated to us
The newly introduced switchdev_handle_fdb_{add,del}_to_device helpers
solved a problem but introduced another one.
net: switchdev: fix FDB entries towards foreign ports not getting propagated to us
The newly introduced switchdev_handle_fdb_{add,del}_to_device helpers
solved a problem but introduced another one. They have a severe design
bug: they do not propagate FDB events on foreign interfaces to us, i.e.
this use case:
br0
/ \
/ \
/ \
/ \
swp0 eno0
(switchdev) (foreign)
when an address is learned on eno0, what is supposed to happen is that
this event should also be propagated towards swp0. Somehow I managed to
convince myself that this did work correctly, but obviously it does not.
The trouble with foreign interfaces is that we must reach a switchdev
net_device pointer through a foreign net_device that has no direct
upper/lower relationship with it. So we need to do exploratory searching
through the lower interfaces of the foreign net_device's bridge upper
(to reach swp0 from eno0, we must check its upper, br0, for lower
interfaces that pass the check_cb and foreign_dev_check_cb). This is
something that the previous code did not do, it just assumed that "dev"
will become a switchdev interface at some point, somehow, probably by
magic.
With this patch, assisted address learning on the CPU port works again
in DSA:
ip link add br0 type bridge
ip link set swp0 master br0
ip link set eno0 master br0
ip link set br0 up
[ 46.708929] mscc_felix 0000:00:00.5 swp0: Adding FDB entry towards eno0, addr 00:04:9f:05:f4:ab vid 0 as host address
Fixes: 8ca07176ab00 ("net: switchdev: introduce a fanout helper for SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE")
Reported-by: Eric Woudstra <ericwouds@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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| bae33f2b | 09-Jan-2021 |
Vladimir Oltean <vladimir.oltean@nxp.com> |
net: switchdev: remove the transaction structure from port attributes
Since the introduction of the switchdev API, port attributes were
transmitted to drivers for offloading using a two-step transac
net: switchdev: remove the transaction structure from port attributes
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 91cf8eceffc1 ("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 2e554a7a5d8a
("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: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek
Reviewed-by: Linus Walleij <linus.walleij@linaro.org> # RTL8366RB
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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| cf6def51 | 09-Jan-2021 |
Vladimir Oltean <vladimir.oltean@nxp.com> |
net: switchdev: delete switchdev_port_obj_add_now
After the removal of the transactional model inside
switchdev_port_obj_add_now, it has no added value and we can just call
switchdev_port_obj_notify
net: switchdev: delete switchdev_port_obj_add_now
After the removal of the transactional model inside
switchdev_port_obj_add_now, it has no added value and we can just call
switchdev_port_obj_notify directly, bypassing this function. Let's
delete it.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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